1
|
Wu K, Wang H, Yang M, Liu L, Sun Z, Hu G, Song Y, Han X, Guo J, Wu K, Feng B, Shen C, Huang Y, Shi Y, Cheng Z, Yang H, Bao L, Pantelides ST, Gao HJ. Gold-Template-Assisted Mechanical Exfoliation of Large-Area 2D Layers Enables Efficient and Precise Construction of Moiré Superlattices. Adv Mater 2024:e2313511. [PMID: 38597395 DOI: 10.1002/adma.202313511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 04/07/2024] [Indexed: 04/11/2024]
Abstract
Moiré superlattices, consisting of rotationally aligned 2D atomically thin layers, provide a highly novel platform for the study of correlated quantum phenomena. However, reliable and efficient construction of moiré superlattices is challenging because of difficulties to accurately angle-align small exfoliated 2D layers and the need to shun wet-transfer processes. Here, efficient and precise construction of various moiré superlattices is demonstrated by picking up and stacking large-area 2D mono- or few-layer crystals with predetermined crystal axes, made possible by a gold-template-assisted mechanical exfoliation method. The exfoliated 2D layers are semiconductors, superconductors, or magnets and their high quality is confirmed by photoluminescence and Raman spectra and by electrical transport measurements of fabricated field-effect transistors and Hall devices. Twisted homobilayers with angle-twisting accuracy of ≈0.3°, twisted heterobilayers with sub-degree angle-alignment accuracy, and multilayer superlattices are precisely constructed and characterized by their moiré patterns, interlayer excitons, and second harmonic generation. The present study paves the way for exploring emergent phenomena in moiré superlattices.
Collapse
Affiliation(s)
- Kang Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Hao Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Meng Yang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Li Liu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Zhenyu Sun
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Guojing Hu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Yanpeng Song
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Xin Han
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing, 100049, P. R. China
| | - Jiangang Guo
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Chengmin Shen
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Yuan Huang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Youguo Shi
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing, 100049, P. R. China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, P. R. China
| | - Zhigang Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, P. R. China
| | - Haitao Yang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- Hefei National Laboratory, Hefei, Anhui, 230088, P. R. China
| | - Lihong Bao
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- Hefei National Laboratory, Hefei, Anhui, 230088, P. R. China
| | - Sokrates T Pantelides
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- Department of Physics and Astronomy & Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, 37235, USA
| | - Hong-Jun Gao
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- Hefei National Laboratory, Hefei, Anhui, 230088, P. R. China
| |
Collapse
|
2
|
Peng X, Zhou Q, Wang CQ, Zhang ZM, Luo Z, Xu SY, Feng B, Fang ZF, Lin Y, Zhuo Y, Jiang XM, Zhao H, Tang JY, Wu D, Che LQ. Dietary supplementation of proteases on growth performance, nutrient digestibility, blood characteristics and gut microbiota of growing pigs fed sorghum-based diets. Animal 2024; 18:101052. [PMID: 38181459 DOI: 10.1016/j.animal.2023.101052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 12/02/2023] [Accepted: 12/04/2023] [Indexed: 01/07/2024] Open
Abstract
Low-tannin sorghum is an excellent energy source in pig diets. However, sorghum contains several anti-nutritional factors that may have negative effects on nutrient digestibility. The impacts of proteases on growth performance, nutrient digestibility, blood parameters, and gut microbiota of growing pigs fed sorghum-based diets were studied in this study. Ninety-six pigs (20.66 ± 0.65 kg BW) were allocated into three groups (eight pens/group, four pigs/pen): (1) CON (control diet, sorghum-based diet included 66.98% sorghum), (2) PRO1 (CON + 200 mg/kg proteases), (3) PRO2 (CON + 400 mg/kg proteases) for 28 d. No differences were observed in growth performance and apparent total tract digestibility (ATTD) of nutrients between CON and PRO1 groups. Pigs fed PRO2 diet had increased (P < 0.05) BW on d 21 and 28, and increased (P < 0.05) average daily gain during d 14-21 and the overall period compared with pigs fed CON diet. In addition, pigs fed PRO2 diet had improved (P < 0.05) ATTD of gross energy, CP, and DM compared with pigs fed CON and PRO1 diets. Pigs fed PRO2 diet had lower (P < 0.05) plasma globulin (GLB) level and higher (P < 0.05) plasma glucose, albumin (ALB) and immunoglobulin G levels, and ALB/GLB ratio than pigs fed CON and PRO1 diets. Furthermore, pigs fed PRO2 diet had decreased (P < 0.05) the relative abundance of Acidobacteriota at the phylum level and increased (P < 0.05) the relative abundance of Prevotella_9 at the genus level. The linear discriminant analysis effect size analysis also showed that pigs fed PRO2 diet had significantly enriched short-chain fatty acid-producing bacteria, such as Subdoligranulum and Parabacteroides. In conclusion, protease supplementation at 400 mg/kg improved the growth performance of growing pigs fed sorghum-based diets, which may be attributed to the improvement of nutrient digestibility, host metabolism, immune status and associated with the altered gut microbiota profiles.
Collapse
Affiliation(s)
- X Peng
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - Q Zhou
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - C Q Wang
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - Z M Zhang
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Z Luo
- Kemin (China) Technologies Co., Ltd., Sanzao, Zhuhai 519040, China
| | - S Y Xu
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - B Feng
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - Z F Fang
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - Y Lin
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - Y Zhuo
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - X M Jiang
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - H Zhao
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - J Y Tang
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - D Wu
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China
| | - L Q Che
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China.
| |
Collapse
|
3
|
Yuan PQ, Lin S, Peng JY, Li YX, Liu YH, Wang P, Zhong HJ, Yang XM, Che LQ, Feng B, Batonon-Alavo DI, Mercier Y, Zhang XL, Lin Y, Xu SY, Li J, Zhuo Y, Wu D, Fang ZF. Effects of dietary methionine supplementation from different sources on growth performance and meat quality of barrows and gilts. Animal 2023; 17:100986. [PMID: 37820406 DOI: 10.1016/j.animal.2023.100986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 08/29/2023] [Accepted: 09/07/2023] [Indexed: 10/13/2023] Open
Abstract
Methionine is indispensable for growth and meat formation in pigs. However, it is still unclear that increasing dietary sulphur-containing amino acid (SAA) levels using different methionine sources affects the growth performance and meat quality of barrows and gilts. To investigate this, 144 pigs (half barrows and half gilts) were fed the control (100% SAA, CON), DL-Methionine (125% SAA, DL-Met)-supplemented, or OH-Methionine (125% SAA, OH-Met)-supplemented diets during the 11-110 kg period. The results showed that plasma methionine levels varied among treatments during the experimental phase, with increased plasma methionine levels observed following increased SAA consumption during the 25-45 kg period. In contrast, pigs fed the DL-Met diet had lower plasma methionine levels than those fed the CON diet (95-110 kg). Additionally, gilts fed the DL-Met or OH-Met diets showed decreased drip loss in longissimus lumborum muscle (LM) compared to CON-fed gilts. OH-Met-fed gilts had higher pH45min values than those fed the CON or DL-Met diets, whereas OH-Met-fed barrows had higher L45min values than those fed the CON or DL-Met diets. Moreover, increased consumption of SAA, regardless of the methionine source, tended to decrease the shear force of the LM in pigs. In conclusion, this study indicates that increasing dietary levels of SAA (+25%) appeared to improve the meat quality of gilts by decreasing drip loss and increasing meat tenderness.
Collapse
Affiliation(s)
- P Q Yuan
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China; Key Laboratory of Agricultural Product Processing and Nutrition Health (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairsand, College of Food Science, Sichuan Agricultural University, Ya'an 625014, People's Republic of China
| | - S Lin
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China; Key Laboratory of Urban Agriculture in South China, Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, People's Republic of China
| | - J Y Peng
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - Y X Li
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - Y H Liu
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - P Wang
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - H J Zhong
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - X M Yang
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - L Q Che
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - B Feng
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | | | - Y Mercier
- Adisseo France S.A.S, CERN, Commentry, France
| | - X L Zhang
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - Y Lin
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - S Y Xu
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - J Li
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - Y Zhuo
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - D Wu
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China
| | - Z F Fang
- Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu 611130, People's Republic of China; Key Laboratory of Agricultural Product Processing and Nutrition Health (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairsand, College of Food Science, Sichuan Agricultural University, Ya'an 625014, People's Republic of China.
| |
Collapse
|
4
|
Chen L, Luo H, Li S, Tan X, Feng B, Jin F. Complexity Metrics and Planning Dose-Based Pretreatment Patient-Specific Quality Assurance Prediction: Classification, Gamma Passing Rates, and DVH Deviation. Int J Radiat Oncol Biol Phys 2023; 117:e371-e372. [PMID: 37785267 DOI: 10.1016/j.ijrobp.2023.06.2472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Patient-specific quality assurance (QA) prediction before treatment is beneficial to the clinical resource allocation and the dosimetric monitoring of the patient plans. The aim of this study is to investigate the potential of complexity metrics of radiotherapy plan and patient planning dose to predict QA result, gamma passing rates and dose-volume indices deviation. MATERIALS/METHODS Planning dose from treatment planning system (TPS), reconstructed dose from a vendor provided QA phantom and complexity metrics of the 499 radiotherapy plans of patients in our institution from March 2022 to September 2022 were used for methodology verification. Gamma passing rate (3%/2mm,10% threshold) 90% was regarded as criterion of QA pass or fail. A deep learning model ResNet-50 was modified to 3D dose processing and a multilayer perceptron (MLP) with three layers were adopted to extract features from 3D dose and 1D metrics in two parallel ways, then, the features were concatenate together to predict QA results. The dataset was split into 349 for train, 50 for validation and 100 for testing. Evaluation of predictions was based on absolute value deviation and area under the curves (AUC) of receiver operator characteristic (ROC) curve. RESULTS In this dataset, 71% (355/499) plans pass the pretreatment QA test. For QA passing prediction in 100 testing cases, the AUC of ROC could achieve 0.92. For gamma passing rates prediction, a mean absolute error (MAE) of 1.8% could be observed for cases with gamma passing rates bigger than 90%, and a MAE of 4.5% deviation could be observed for cases with gamma passing rates from 80% to 90%. For PTV ΔD95 (%) and PTV ΔHI (%), the MAE of prediction and ground truth is 1%. The model with only complexity metrics and only 3D dose could achieve the AUC of ROC 0.91 and 0.84, respectively. CONCLUSION The complexity metrics and 3D planning dose-based model could predict pretreatment patient specific QA results with high accuracy and the complexity metrics play a leading role in the model. Dose-volume metrics deviations of PTV could be predicted and more clinically useful information could be provided.
Collapse
Affiliation(s)
- L Chen
- Radiation Oncology Center, Chongqing University Cancer Hospital, Chongqing, China
| | - H Luo
- Department of Radiation Oncology, Chongqing University Cancer Hospital & Chongqing Cancer Institute & Chongqing Cancer Hospital, Chongqing, China
| | - S Li
- Radiation Oncology Center, Chongqing University Cancer Hospital, Chongqing, China
| | - X Tan
- Radiation Oncology Center, Chongqing University Cancer Hospital, Chongqing, China
| | - B Feng
- Radiation Oncology Center, Chongqing University Cancer Hospital, Chongqing, China
| | - F Jin
- Radiation Oncology Center, Chongqing University Cancer Hospital, Chongqing, China
| |
Collapse
|
5
|
Liu PM, Feng B, Shi JF, Feng HJ, Hu ZJ, Chen YH, Zhang JP. A deep-learning model using enhanced chest CT images to predict PD-L1 expression in non-small-cell lung cancer patients. Clin Radiol 2023; 78:e689-e697. [PMID: 37460338 DOI: 10.1016/j.crad.2023.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 05/11/2023] [Accepted: 05/18/2023] [Indexed: 09/03/2023]
Abstract
AIM To develop a deep-learning model using contrast-enhanced chest computed tomography (CT) images to predict programmed death-ligand 1 (PD-L1) expression in patients with non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS Preoperative enhanced chest CT images and immunohistochemistry results for PD-L1 expression (<1% and ≥1% were defined as negative and positive, respectively) were collected retrospectively from 125 NSCLC patients to train and validate a deep-learning radiomics model (DLRM) for the prediction of PD-L1 expression in tumours. The DLRM was developed by combining the deep-learning signature (DLS) obtained from a convolutional neural network and clinicopathological factors. The indexes of the area under the curve (AUC), integrated discrimination improvement (IDI), and decision curve analysis (DCA) were used to evaluate the efficiency of the DLRM. RESULTS DLS and tumour stage were identified as independent predictors of PD-L1 expression by the DLRM. The AUCs of the DLRM were 0.804 (95% confidence interval: 0.697-0.911) and 0.804 (95% confidence interval: 0.679-0.929) in the training and validation cohorts, respectively. IDI analysis showed the DLRM had better diagnostic accuracy than DLS (0.0028 [p<0.05]) in the validation cohort. Additionally, DCA revealed that the DLRM had more net benefit than the DLS for clinical utility. CONCLUSION The proposed DLRM using enhanced chest CT images could function as a non-invasive diagnostic tool to differentiate PD-L1 expression in NSCLC patients.
Collapse
Affiliation(s)
- P M Liu
- Cancer Center, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China; Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - B Feng
- School of Electronic Information and Automation, Guilin University of Aerospace Technology, Guilin, Guangxi, 541004, China
| | - J F Shi
- School of Electronic Information and Automation, Guilin University of Aerospace Technology, Guilin, Guangxi, 541004, China
| | - H J Feng
- Cancer Center, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China; Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Z J Hu
- School of Electronic Information and Automation, Guilin University of Aerospace Technology, Guilin, Guangxi, 541004, China
| | - Y H Chen
- School of Electronic Information and Automation, Guilin University of Aerospace Technology, Guilin, Guangxi, 541004, China
| | - J P Zhang
- Cancer Center, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China; Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| |
Collapse
|
6
|
Yang X, Yang H, Feng B, Jin F, Luo H. Feasibility of Using Pseudo-CT for Dosimetry, Radiomics, and Efficacy Assessment in IMRT/VMAT of Brain Tumors: A Multi-Omics Analysis. Int J Radiat Oncol Biol Phys 2023; 117:e494. [PMID: 37785558 DOI: 10.1016/j.ijrobp.2023.06.1730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Pseudo-CT generated by convolutional neural networks (CNN) and planning MRI has facilitated the promotion of MRI-Only. The technology not only reduces the time and money spent on CT scans, but also eliminates the cumbersome CT-MR registration. The feasibility in Stereotactic Brain Radiotherapy has been analyzed in previous studies by our team. However, when the prescribed requirements are not met, IMRT/VMAT are still selected. The study aims to evaluate the feasibility of pseudo-CT in IMRT/VMAT for brain cancer via the following 5 aspects: (1) image difference, (2) dose accuracy, (3) radiomics feature, (4) efficacy assessment, and (5) correlation analysis. MATERIALS/METHODS Brain tumor patients who had received radiotherapy at our institution and had planning MRI and CT were included in the study. Redesign of IMRT and VMAT radiotherapy plans according to 3 × 15Gy for each patient. Hounsfield unit (HU) values for PTV and OARs were used to assess image differences. And dose accuracy analysis contained a 2D dose volume histogram (DVH) metrics (Dmax, Dmean, D2%, D50%, D98%, HI, CI) and 3D gamma metrics (criteria: 1-3%/2mm, 1%/1mm, 10% threshold). Then 107 original image features of PTV and OARs were extracted for radiometry analysis. And tumor control probability (TCP) of PTV (Poisson model) and normal tissue complication probability (NTCP) of OARs (Lyman-Kutcher-Burman model) were used for the variance analysis of efficacy assessment. Wilcox-test was used for significance of differences test (0.05), and spearman correlation analysis was used to explore the key features of the dose bias. RESULTS A total of 42 patients were included, with 42 planning CTs and pseudo-CTs (mDixon-T1), and 38 pseudo-CTs (mDixon-T1-CE). The median volume of PTV was 4.1 cc (range 0.5-27.3), with no significant differences in HU, DVH, 3D gamma, and NTCP/TCP metrics. The median local gamma passing rates (1%/1mm) between planning CTs and pseudo-CTs (mDixon-T1) were 93.1% (range 65.5%-99.7%, IMRT) and 93.3% (range 63.9%-99.6%, VMAT). And more than 85% original radiomics features have significant difference. Further, the feature HU-Min was found to be more correlated with dose metrics in the correlation analysis. We speculate that it may be caused by the smoothing of the low frequency signal before outputting image. And since Shape_MeshVolume, Shape_VoxelVolume and PTV volume difference are highly correlated with dose deviation, it indicates that dose deviation affected by CT-MR registration. CONCLUSION This study has the potential to provide guidance for the clinical application of pseudo-CT in the MRI-Only workflow with IMRT/VMAT for brain tumors. These quantitative results strongly indicate pseudo-CT can be used as a substitute for the initial CT in IMRT/VMAT for small brain lesions (size <5 cm, numbers <5), but not for radiomics analysis. Additionally, the impact of inter-image differences on dose accuracy is less significant compared to the deviation caused by image registration.
Collapse
Affiliation(s)
- X Yang
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - H Yang
- Department of Radiation Oncology, Chongqing University Cancer Hospital & Chongqing Cancer Institute & Chongqing Cancer Hospital, Chongqing, China
| | - B Feng
- Radiation Oncology Center, Chongqing University Cancer Hospital, Chongqing, China
| | - F Jin
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - H Luo
- Department of Radiation Oncology, Chongqing University Cancer Hospital & Chongqing Cancer Institute & Chongqing Cancer Hospital, Chongqing, China
| |
Collapse
|
7
|
Zhou S, Liao L, Chen L, Feng B, He X, Bai X, Song C, Wu K. Ferroelectricity in Epitaxial Perovskite Oxide Bi 2WO 6 Films with One-Unit-Cell Thickness. Nano Lett 2023; 23:7838-7844. [PMID: 37590032 DOI: 10.1021/acs.nanolett.3c01426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
Retaining ferroelectricity in ultrathin films or nanostructures is crucial for miniaturizing ferroelectric devices, but it is a challenging task due to intrinsic depolarization and size effects. In this study, we have shown that it is possible to stably maintain in-plane polarization in an extremely thin, one-unit-cell thick epitaxial Bi2WO6 film. The use of a perfectly lattice-matched NdGaO3 (110) substrate for the Bi2WO6 film minimizes strain and enhances stability. We attribute the residual polarization in this ultrathin film to the crystal stability of the Bi-O octahedral framework against structural distortions. Our findings suggest that ferroelectricity can surpass the critical thickness limit through proper strain engineering, and the Bi2WO6/NdGaO3 (110) system presents a potential platform for designing low-energy consumption, nonvolatile ferroelectric memories.
Collapse
Affiliation(s)
- Song Zhou
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lei Liao
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoyue He
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Xuedong Bai
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chuangye Song
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing 100871, China
| |
Collapse
|
8
|
Li W, Gao Q, Wang Y, Cheng P, Zhang YQ, Feng B, Hu Z, Wu K, Chen L. Moiré-Pattern Modulated Electronic Structures of GaSe/HOPG Heterostructure. Small 2023; 19:e2302192. [PMID: 37127860 DOI: 10.1002/smll.202302192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/18/2023] [Indexed: 05/03/2023]
Abstract
Conventional two-dimensional electron gas (2DEG) typically occurs at the interface of semiconductor heterostructures and noble metal surfaces, but it is scarcely observed in individual 2D semiconductors. In this study, few-layer gallium selenide (GaSe) grown on highly ordered pyrolytic graphite (HOPG) is demonstrated using scanning tunneling microscopy and spectroscopy (STM/STS), revealing that the coexistence of quantum well states (QWS) and 2DEG. The QWS are located in the valence bands and exhibit a peak feature, with the number of quantum wells being equal to the number of atomic layers. Meanwhile, the 2DEG is located in the conduction bands and exhibits a standing-wave feature. Additionally, monolayer GaSe/HOPG heterostructures with different stacking angles (0°, 33°, 8°) form distinct moiré patterns that arise from lattice mismatch and angular rotation between adjacent atomic layers in 2D materials, which effectively modulate the electron effective mass, charge redistribution, and band gap of GaSe. Overall, this work reveals a paradigm of band engineering based on layer numbers and moiré patterns that can modulate the electronic properties of 2D materials.
Collapse
Affiliation(s)
- Wenhui Li
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Qian Gao
- School of Physics, Nankai University, Tianjin, 300071, China
| | - Yu Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Yi-Qi Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Zhenpeng Hu
- School of Physics, Nankai University, Tianjin, 300071, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| |
Collapse
|
9
|
Liu H, Wang A, Zhang P, Ma C, Chen C, Liu Z, Zhang YQ, Feng B, Cheng P, Zhao J, Chen L, Wu K. Atomic-scale manipulation of single-polaron in a two-dimensional semiconductor. Nat Commun 2023; 14:3690. [PMID: 37344475 DOI: 10.1038/s41467-023-39361-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 06/09/2023] [Indexed: 06/23/2023] Open
Abstract
Polaron is a composite quasiparticle derived from an excess carrier trapped by local lattice distortion, and it has been studied extensively for decades both theoretically and experimentally. However, atomic-scale creation and manipulation of single-polarons in real space have still not been achieved so far, which precludes the atomistic understanding of the properties of polarons as well as their applications. Herein, using scanning tunneling microscopy, we succeeded to create single polarons in a monolayer two-dimensional (2D) semiconductor, CoCl2. Combined with first-principles calculations, two stable polaron configurations, centered at atop and hollow sites, respectively, have been revealed. Remarkably, a series of manipulation progresses - from creation, erasure, to transition - can be accurately implemented on individual polarons. Our results pave the way to understand the physics of polaron at atomic level, and the easy control of single polarons in 2D semiconductor may open the door to 2D polaronics including the data storage.
Collapse
Affiliation(s)
- Huiru Liu
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Aolei Wang
- Department of Physics, University of Science and Technology of China, 230026, Hefei, Anhui, China
| | - Ping Zhang
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Chen Ma
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Caiyun Chen
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Zijia Liu
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
- Songshan Lake Materials Laboratory, Dongguan, 523808, Guangdong, China
| | - Yi-Qi Zhang
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, 100871, Beijing, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Jin Zhao
- Department of Physics, University of Science and Technology of China, 230026, Hefei, Anhui, China.
- ICQD/Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, 230026, Hefei, Anhui, China.
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, 15260, PA, USA.
- Hefei National Laboratory, University of Science and Technology of China, 230088, Hefei, Anhui, China.
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China.
- Songshan Lake Materials Laboratory, Dongguan, 523808, Guangdong, China.
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China.
- Songshan Lake Materials Laboratory, Dongguan, 523808, Guangdong, China.
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, 100871, Beijing, China.
| |
Collapse
|
10
|
Hu X, Zhang RW, Ma DS, Cai Z, Geng D, Sun Z, Zhao Q, Gao J, Cheng P, Chen L, Wu K, Yao Y, Feng B. Realization of a Two-Dimensional Checkerboard Lattice in Monolayer Cu 2N. Nano Lett 2023. [PMID: 37321211 DOI: 10.1021/acs.nanolett.3c01111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Two-dimensional checkerboard lattice, the simplest line-graph lattice, has been intensively studied as a toy model, while material design and synthesis remain elusive. Here, we report theoretical prediction and experimental realization of the checkerboard lattice in monolayer Cu2N. Experimentally, monolayer Cu2N can be realized in the well-known N/Cu(100) and N/Cu(111) systems that were previously mistakenly believed to be insulators. Combined angle-resolved photoemission spectroscopy measurements, first-principles calculations, and tight-binding analysis show that both systems host checkerboard-derived hole pockets near the Fermi level. In addition, monolayer Cu2N has outstanding stability in air and organic solvents, which is crucial for further device applications.
Collapse
Affiliation(s)
- Xuegao Hu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Run-Wu Zhang
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics and Beijing Key Lab of Nanophotonics Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Da-Shuai Ma
- Institute for Structure and Function & Department of Physics, Chongqing University, Chongqing 400044, China
| | - Zhihao Cai
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Daiyu Geng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhenyu Sun
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiaoxiao Zhao
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jisong Gao
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing 100871, China
| | - Yugui Yao
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics and Beijing Key Lab of Nanophotonics Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing 100871, China
| |
Collapse
|
11
|
Li W, Zhang X, Yang J, Zhou S, Song C, Cheng P, Zhang YQ, Feng B, Wang Z, Lu Y, Wu K, Chen L. Emergence of ferroelectricity in a nonferroelectric monolayer. Nat Commun 2023; 14:2757. [PMID: 37179407 PMCID: PMC10183010 DOI: 10.1038/s41467-023-38445-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
Ferroelectricity in ultrathin two-dimensional (2D) materials has attracted broad interest due to potential applications in nonvolatile memory, nanoelectronics and optoelectronics. However, ferroelectricity is barely explored in materials with native centro or mirror symmetry, especially in the 2D limit. Here, we report the first experimental realization of room-temperature ferroelectricity in van der Waals layered GaSe down to monolayer with mirror symmetric structures, which exhibits strong intercorrelated out-of-plane and in-plane electric polarization. The origin of ferroelectricity in GaSe comes from intralayer sliding of the Se atomic sublayers, which breaks the local structural mirror symmetry and forms dipole moment alignment. Ferroelectric switching is demonstrated in nano devices fabricated with GaSe nanoflakes, which exhibit exotic nonvolatile memory behavior with a high channel current on/off ratio. Our work reveals that intralayer sliding is a new approach to generate ferroelectricity within mirror symmetric monolayer, and offers great opportunity for novel nonvolatile memory devices and optoelectronics applications.
Collapse
Affiliation(s)
- Wenhui Li
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Xuanlin Zhang
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Jia Yang
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- National Center for Nanoscience and Technology, Chinese Academy of Sciences, Beijing, 100190, China
| | - Song Zhou
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Chuangye Song
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Yi-Qi Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Zhenxing Wang
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- National Center for Nanoscience and Technology, Chinese Academy of Sciences, Beijing, 100190, China
| | - Yunhao Lu
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, Zhejiang University, Hangzhou, 310027, China.
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China.
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China.
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China.
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China.
| |
Collapse
|
12
|
Liu H, Li H, He Y, Cheng P, Zhang YQ, Feng B, Li H, Wu K, Chen L. Condensation and asymmetric amplification of chirality in achiral molecules adsorbed on an achiral surface. Nat Commun 2023; 14:2100. [PMID: 37055409 PMCID: PMC10101975 DOI: 10.1038/s41467-023-37904-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 04/04/2023] [Indexed: 04/15/2023] Open
Abstract
The origin of homochirality in nature is an important but open question. Here, we demonstrate a simple organizational chiral system constructed by achiral carbon monoxide (CO) molecules adsorbed on an achiral Au(111) substrate. Combining scanning tunneling microscope (STM) measurements with density-functional-theory (DFT) calculations, two dissymmetric cluster phases consisting of chiral CO heptamers are revealed. By applied high bias voltage, the stable racemic cluster phase can be transformed into a metastable uniform phase consisting of CO monomers. Further, during the recondensation of a cluster phase after lowering down bias voltage, an enantiomeric excess and its chiral amplification occur, resulting in a homochirality. Such asymmetry amplification is found to be both kinetically feasible and thermodynamically favorable. Our observations provide insight into the physicochemical origin of homochirality through surface adsorption and suggest a general phenomenon that can influence enantioselective chemical processes such as chiral separations and heterogeneous asymmetric catalysis.
Collapse
Affiliation(s)
- Huiru Liu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, PR China
- School of physics, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Heping Li
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China
| | - Yu He
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, PR China
- School of physics, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, PR China
- School of physics, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Yi-Qi Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, PR China
- School of physics, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, PR China
- School of physics, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Hui Li
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China.
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, PR China.
- School of physics, University of Chinese Academy of Sciences, Beijing, 100049, PR China.
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, PR China.
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, PR China.
- School of physics, University of Chinese Academy of Sciences, Beijing, 100049, PR China.
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, PR China.
| |
Collapse
|
13
|
Yu X, Feng B, Lan Y, Li J, Ye G, Li Q, Zhao F, Gu Y, You D, Zhu Y, Yu M, Wang H, Yang H. A 2-Stage Root Analog Implant with Compact Structure, Uniform Roughness, and High Accuracy. J Dent Res 2023; 102:636-644. [PMID: 37036092 DOI: 10.1177/00220345231160670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2023] Open
Abstract
Immediate implant placement has the advantages of shortening the operation time, reducing the treatment cycle and cost. At present, this technology has been used widely, but the indications of immediate implantation are still limited. Here, a novel type of root analog implant (RAI) was manufactured by selective laser melting technology to address the limitation. Under optimized condition, RAIs were printed with the internal density of 99.73% and the uniform surface roughness of 11 μm (Sa). Besides, the deviation between RAI specimen and design models is controlled within 0.15 mm after optimizing scanning parameters. The substrate printed could promote human bone marrow stromal cell proliferation, spreading, and osteogenic differentiation. The bone-implant contact (BIC, 75% ± 7%) and bone volume/total volume (BV/TV, 74% ± 7%) of RAIs were significantly higher than that of conventional implants (BIC, 66% ± 5%; BV/TV, 62% ± 5%) in in vivo experiments. Further, customized abutments were designed for the RAIs, improving the masticatory ability of the beagle dogs after crown restoration. This study aims to design a personalized 2-stage RAI with compact structure and uniform roughness, in order to achieve better fracture resistance, initial osseointegration efficiency, and dispersed stress in immediate implantation. It provides a certain guiding value for standardizing the manufacture and clinical application of RAI in immediate implantation.
Collapse
Affiliation(s)
- X Yu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - B Feng
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Y Lan
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - J Li
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - G Ye
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Q Li
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - F Zhao
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Y Gu
- State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou, Zhejiang, China
| | - D You
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Y Zhu
- State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou, Zhejiang, China
| | - M Yu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - H Wang
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Clinical Research Center for Oral Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang, China
| | - H Yang
- State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou, Zhejiang, China
| |
Collapse
|
14
|
Lv H, Chen C, Li W, Zhuo Z, Cheng P, Zhang YQ, Feng B, Wu K, Wu X, Chen L. Selective binding and periodic arrangement of magic boron clusters on monolayer borophene. Proc Natl Acad Sci U S A 2023; 120:e2215131120. [PMID: 36877857 PMCID: PMC10089196 DOI: 10.1073/pnas.2215131120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Accepted: 12/30/2022] [Indexed: 03/08/2023] Open
Abstract
The synthesis and characterization of small boron clusters with unique size and regular arrangement are crucial for boron chemistry and two-dimensional borophene materials. In this study, together with theoretical calculations, the joint molecular beam epitaxy and scanning tunneling microscopy experiments achieve the formation of unique B5 clusters on monolayer borophene (MLB) on a Cu(111) surface. The B5 clusters tend to selectively bind to specific sites of MLB with covalent boron-boron bonds in the periodic arrangement, which can be ascribed to the charge distribution and electron delocalization character of MLB and also prohibits nearby co-adsorption of B5 clusters. Furthermore, the close-packed adsorption of B5 clusters would facilitate the synthesis of bilayer borophene, exhibiting domino effect-like growth mode. The successful growth and characterization of uniform boron clusters on a surface enrich the boron-based nanomaterials and reveal the essential role of small clusters during the growth of borophene.
Collapse
Affiliation(s)
- Haifeng Lv
- Hefei National Research Center for Physical Sciences at the Microscale, Synergetic Innovation of Quantum Information and Quantum Technology, University of Science and Technology of China, Hefei, Anhui230026, China
- Chinese Academy of Sciences (CAS) Center for Excellence in Nanoscience, and School of Chemistry and Materials Sciences, University of Science and Technology of China, Hefei, Anhui230026, China
| | - Caiyun Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Wenbin Li
- Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Zhiwen Zhuo
- Hefei National Research Center for Physical Sciences at the Microscale, Synergetic Innovation of Quantum Information and Quantum Technology, University of Science and Technology of China, Hefei, Anhui230026, China
- Chinese Academy of Sciences (CAS) Center for Excellence in Nanoscience, and School of Chemistry and Materials Sciences, University of Science and Technology of China, Hefei, Anhui230026, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100190, China
| | - Yi-Qi Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong523808, China
| | - Xiaojun Wu
- Hefei National Research Center for Physical Sciences at the Microscale, Synergetic Innovation of Quantum Information and Quantum Technology, University of Science and Technology of China, Hefei, Anhui230026, China
- Chinese Academy of Sciences (CAS) Center for Excellence in Nanoscience, and School of Chemistry and Materials Sciences, University of Science and Technology of China, Hefei, Anhui230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui230088, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong523808, China
| |
Collapse
|
15
|
Wang Y, Gao Q, Li W, Cheng P, Zhang YQ, Feng B, Hu Z, Wu K, Chen L. Nearly Ideal Two-Dimensional Electron Gas Hosted by Multiple Quantized Kronig-Penney States Observed in Few-Layer InSe. ACS Nano 2022; 16:13014-13021. [PMID: 35943244 DOI: 10.1021/acsnano.2c05556] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
A theoretical ideal two-dimensional electron gas (2DEG) was characterized by a flat density of states independent of energy. Compared with conventional two-dimensional free-electron systems in semiconductor heterojunctions and noble metal surfaces, we report here the achievement of ideal 2DEG with multiple quantized states in few-layer InSe films. The multiple quantum well states (QWSs) in few-layer InSe films are found, and the number of QWSs is strictly equal to the number of atomic layers. The multiple stair-like DOS as well as multiple bands with parabolic dispersion both characterize ideal 2DEG features in these QWSs. Density functional theory calculations and numerical simulations based on quasi-bounded square potential wells described as the Kronig-Penney model provide a consistent explanation of 2DEG in the QWSs. Our work demonstrates that 2D van der Waals materials are ideal systems for realizing 2DEG hosted by multiple quantized Kronig-Penney states, and the semiconducting nature of the material provides a better chance for construction of high-performance electronic devices utilizing these states, for example, superlattice devices with negative differential resistance.
Collapse
Affiliation(s)
- Yu Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Qian Gao
- School of Physics, Nankai University, Tianjin 300071, China
| | - Wenhui Li
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Yi-Qi Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Zhenpeng Hu
- School of Physics, Nankai University, Tianjin 300071, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| |
Collapse
|
16
|
Sun Z, Zhou H, Wang C, Kumar S, Geng D, Yue S, Han X, Haraguchi Y, Shimada K, Cheng P, Chen L, Shi Y, Wu K, Meng S, Feng B. Observation of Topological Flat Bands in the Kagome Semiconductor Nb 3Cl 8. Nano Lett 2022; 22:4596-4602. [PMID: 35536689 DOI: 10.1021/acs.nanolett.2c00778] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The destructive interference of wavefunctions in a kagome lattice can give rise to topological flat bands (TFBs) with a highly degenerate state of electrons. Recently, TFBs have been observed in several kagome metals, including Fe3Sn2, FeSn, CoSn, and YMn6Sn6. Nonetheless, kagome materials that are both exfoliable and semiconducting are lacking, which seriously hinders their device applications. Herein, we show that Nb3Cl8, which hosts a breathing kagome lattice, is gapped out because of the absence of inversion symmetry, while the TFBs survive because of the protection of the mirror reflection symmetry. By angle-resolved photoemission spectroscopy measurements and first-principles calculations, we directly observe the TFBs and a moderate band gap in Nb3Cl8. By mechanical exfoliation, we successfully obtain monolayer Nb3Cl8, which is stable under ambient conditions. In addition, our calculations show that monolayer Nb3Cl8 has a magnetic ground state, thus providing opportunities to study the interplay among geometry, topology, and magnetism.
Collapse
Affiliation(s)
- Zhenyu Sun
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Hui Zhou
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Cuixiang Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Shiv Kumar
- Hiroshima Synchrotron Radiation Center, Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046, Japan
| | - Daiyu Geng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Shaosheng Yue
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xin Han
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Yuya Haraguchi
- Department of Applied Physics and Chemical Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Kenya Shimada
- Hiroshima Synchrotron Radiation Center, Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046, Japan
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
| | - Youguo Shi
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
| | - Sheng Meng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| |
Collapse
|
17
|
Zhang P, Chen L, Sheng S, Hu W, Liu H, Ma C, Liu Z, Feng B, Cheng P, Zhang Y, Chen L, Zhao J, Wu K. Melamine self-assembly and dehydrogenation on Ag(111) studied by tip-enhanced Raman spectroscopy. J Chem Phys 2022; 156:204301. [DOI: 10.1063/5.0091353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The adsorption and self-assembly structures of melamine molecules on an Ag(111) surface are studied by low temperature scanning tunneling microscopy (STM) combined with tip-enhanced Raman spectroscopy (TERS). Two ordered self-assembly phases of melamine molecules on Ag(111) were studied by STM and TERS, combining with first-principles simulations. The α-phase consists of flat-lying melamine molecules, while the β-phase consists of mixed up-standing/tilted melamine molecules. Moreover, dehydrogenation of melamine can be controlled by annealing the sample as well as by a tip-enhanced photo-catalytic effect. Our work demonstrates TERS as a powerful tool not only for investigating the configuration and vibration properties of molecules on a metal surface with high spatial resolution but also for manipulating the chemical reactions with tip and photo-induced effects.
Collapse
Affiliation(s)
- Ping Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Linjie Chen
- Department of Chemical Physics, School of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Shaoxiang Sheng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Wenqi Hu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Huiru Liu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Chen Ma
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Zijia Liu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Yiqi Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Jin Zhao
- Department of Physics, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| |
Collapse
|
18
|
Sun Z, Han X, Cai Z, Yue S, Geng D, Rong D, Zhao L, Zhang YQ, Cheng P, Chen L, Zhou X, Huang Y, Wu K, Feng B. Exfoliation of 2D van der Waals crystals in ultrahigh vacuum for interface engineering. Sci Bull (Beijing) 2022; 67:1345-1351. [DOI: 10.1016/j.scib.2022.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 04/26/2022] [Accepted: 05/24/2022] [Indexed: 12/01/2022]
|
19
|
Qin W, Ma JJ, Feng B. [Medial border of D3 lymphadenectomy for right colon cancer]. Zhonghua Wei Chang Wai Ke Za Zhi 2022; 25:305-308. [PMID: 35461197 DOI: 10.3760/cma.j.cn441530-20220129-00041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The extent of D3 lymphadenectomy for right colon cancer, especially the medial border of central lymph node dissection remains controversial. D3 lymphadenectomy and complete mesocolon excision (CME) are two standard procedures for locally advanced right colon carcinoma. D3 lymphadenectomy determines the medial border according to the distribution of the lymph nodes. The mainstream medial border should be the left side of superior mesenteric vein (SMV) according to the definition of D3, but there are also some reports that regards the left side of superior mesenteric artery (SMA) as the medial border. In contrast, the CME procedure emphasizes the beginning of the colonic mesentery and the left side of SMA should be considered as the medial border. Combined with the anatomical basis, oncological efficacy and technical feasibility of D3 lymph node dissection, we think that it is safe and feasible to take the left side of SMA as the medial boundary of D3 lymph node dissection. This procedure not only takes into account the integrity of mesangial and regional lymph node dissection, but also dissects more distant lymph nodes at risk of metastasis. It has its anatomical basis and potential oncological advantages. However, at present, this technical concept is still in the exploratory stage in practice, and the related clinical evidence is not sufficient.
Collapse
Affiliation(s)
- W Qin
- Department of General Surgery, Shanghai Clinical Medical Center for Minimally Invasive Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - J J Ma
- Department of General Surgery, Shanghai Clinical Medical Center for Minimally Invasive Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - B Feng
- Department of General Surgery, Shanghai Clinical Medical Center for Minimally Invasive Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| |
Collapse
|
20
|
Zhang J, Zhang X, Wang Y, Cheng P, Feng B, Wu K, Lu Y, Chen L. Giant Bandgap Engineering in Two-Dimensional Ferroelectric α-In 2Se 3. J Phys Chem Lett 2022; 13:3261-3268. [PMID: 35389224 DOI: 10.1021/acs.jpclett.2c00618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Bandgap engineering is an efficient strategy for controlling the physical properties of semiconductor materials. For flexible two-dimensional (2D) materials, strain provides a nondestructive and adjustable method for bandgap adjustment. Here, we propose that, in 2D materials with out-of-plane ferroelectricity, the antibonding nature of the valence band maximum and conduction band minimum and polarized charge distribution induced by ferroelectricity give rise to giant changes of the bandgap under curvature strain field. This hypothesis was proven by scanning tunneling microscopy/spectroscopy measurements on monolayer α-In2Se3 that revealed that the bandgap of α-In2Se3 increases significantly due to bending. Both experiments and theoretical calculations indicated that the bandgap increases monotonically with the degree of bending of the α-In2Se3 layer. Our work suggests that bending is an effective method for tuning the gaps of 2D ferroelectric materials, providing a new platform for bandgap engineering under the combination of ferroelectricity and strain field.
Collapse
Affiliation(s)
- Jiaxiang Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Xuanlin Zhang
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Yu Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Yunhao Lu
- State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
- Zhejiang Province Key Laboratory of Quantum Technology and Device, Department of Physics, Zhejiang University, Hangzhou 310027, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| |
Collapse
|
21
|
Yue S, Zhou H, Feng Y, Wang Y, Sun Z, Geng D, Arita M, Kumar S, Shimada K, Cheng P, Chen L, Yao Y, Meng S, Wu K, Feng B. Observation of One-Dimensional Dirac Fermions in Silicon Nanoribbons. Nano Lett 2022; 22:695-701. [PMID: 35029399 DOI: 10.1021/acs.nanolett.1c03862] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Dirac materials, which feature Dirac cones in the reciprocal space, have been one of the hottest topics in condensed matter physics in the past decade. To date, 2D and 3D Dirac Fermions have been extensively studied, while their 1D counterparts are rare. Recently, Si nanoribbons (SiNRs), which are composed of alternating pentagonal Si rings, have attracted intensive attention. However, the electronic structure and topological properties of SiNRs are still elusive. Here, by angle-resolved photoemission spectroscopy, scanning tunneling microscopy/spectroscopy measurements, first-principles calculations, and tight-binding model analysis, we demonstrate the existence of 1D Dirac Fermions in SiNRs. Our theoretical analysis shows that the Dirac cones derive from the armchairlike Si chain in the center of the nanoribbon and can be described by the Su-Schrieffer-Heeger model. These results establish SiNRs as a platform for studying the novel physical properties in 1D Dirac materials.
Collapse
Affiliation(s)
- Shaosheng Yue
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hui Zhou
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ya Feng
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Yue Wang
- Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), Beijing Key Lab of Nanophotonics Ultrafine Optoelectronic Systems, and School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Zhenyu Sun
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Daiyu Geng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Masashi Arita
- Hiroshima Synchrotron Radiation Center, Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046, Japan
| | - Shiv Kumar
- Hiroshima Synchrotron Radiation Center, Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046, Japan
| | - Kenya Shimada
- Hiroshima Synchrotron Radiation Center, Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046, Japan
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Yugui Yao
- Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), Beijing Key Lab of Nanophotonics Ultrafine Optoelectronic Systems, and School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Sheng Meng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
22
|
Zhao Y, Siri S, Feng B, Pierce DM. Toward Elucidating the Physiological Impacts of Residual Stresses in the Colorectum. J Biomech Eng 2022; 144:1114807. [PMID: 34286820 PMCID: PMC8420795 DOI: 10.1115/1.4051846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Indexed: 01/03/2023]
Abstract
Irritable bowel syndrome afflicts 10-20% of the global population, causing visceral pain with increased sensitivity to colorectal distension and normal bowel movements. Understanding and predicting these biomechanics will further advance our understanding of visceral pain and complement the existing literature on visceral neurophysiology. We recently performed a series of experiments at three longitudinal segments (colonic, intermediate, and rectal) of the distal 30 mm of colorectums of mice. We also established and fitted constitutive models addressing mechanical heterogeneity in both the through-thickness and longitudinal directions of the colorectum. Afferent nerve endings, strategically located within the submucosa, are likely nociceptors that detect concentrations of mechanical stresses to evoke the perception of pain from the viscera. In this study, we aim to: (1) establish and validate a method for incorporating residual stresses into models of colorectums, (2) predict the effects of residual stresses on the intratissue mechanics within the colorectum, and (3) establish intratissue distributions of stretches and stresses within the colorectum in vivo. To these ends we developed two-layered, composite finite element models of the colorectum based on our experimental evidence and validated our approaches against independent experimental data. We included layer- and segment-specific residual stretches/stresses in our simulations via the prestrain algorithm built into the finite element software febio. Our models and modeling approaches allow researchers to predict both organ and intratissue biomechanics of the colorectum and may facilitate better understanding of the underlying mechanical mechanisms of visceral pain.
Collapse
Affiliation(s)
- Y. Zhao
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT 06269; Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269
| | - S. Siri
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269
| | - B. Feng
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269
| | - D. M. Pierce
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT 06269; Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269,e-mail:
| |
Collapse
|
23
|
Chen C, Lv H, Zhang P, Zhuo Z, Wang Y, Ma C, Li W, Wang X, Feng B, Cheng P, Wu X, Wu K, Chen L. Synthesis of bilayer borophene. Nat Chem 2022; 14:25-31. [PMID: 34764470 DOI: 10.1038/s41557-021-00813-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 09/16/2021] [Indexed: 11/09/2022]
Abstract
As the nearest-neighbour element to carbon, boron is theoretically predicted to have a planar two-dimensional form, named borophene, with novel properties, such as Dirac fermions and superconductivity. Several polymorphs of monolayer borophene have been grown on metal surfaces, yet thicker bilayer and few-layer nanosheets remain elusive. Here we report the synthesis of large-size, single-crystalline bilayer borophene on the Cu(111) surface by molecular beam epitaxy. Combining scanning tunnelling microscopy and first-principles calculations, we show that bilayer borophene consists of two stacked monolayers that are held together by covalent interlayer boron-boron bonding, and each monolayer has β12-like structures with zigzag rows. The formation of a bilayer is associated with a large transfer and redistribution of charge in the first boron layer on Cu(111), which provides additional electrons for the bonding of additional boron atoms, enabling the growth of the second layer. The bilayer borophene is shown to possess metallic character, and be less prone to being oxidized than its monolayer counterparts.
Collapse
Affiliation(s)
- Caiyun Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Haifeng Lv
- Hefei National Laboratory for Physical Sciences at the Microscale, Synergetic Innovation of Quantum Information and Quantum Technology, CAS Center for Excellence in Nanoscience, and School of Chemistry and Materials Sciences, University of Science and Technology of China, Hefei, China
| | - Ping Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Zhiwen Zhuo
- Hefei National Laboratory for Physical Sciences at the Microscale, Synergetic Innovation of Quantum Information and Quantum Technology, CAS Center for Excellence in Nanoscience, and School of Chemistry and Materials Sciences, University of Science and Technology of China, Hefei, China
| | - Yu Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Chen Ma
- Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Wenbin Li
- Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xuguang Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xiaojun Wu
- Hefei National Laboratory for Physical Sciences at the Microscale, Synergetic Innovation of Quantum Information and Quantum Technology, CAS Center for Excellence in Nanoscience, and School of Chemistry and Materials Sciences, University of Science and Technology of China, Hefei, China.
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing, China. .,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China. .,Songshan Lake Materials Laboratory, Dongguan, China.
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, China. .,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China. .,Songshan Lake Materials Laboratory, Dongguan, China.
| |
Collapse
|
24
|
Wang Y, Jia Y, Ren H, Lao C, Peng W, Feng B, Wang J. A mechanical, electrical dual autonomous self-healing multifunctional composite hydrogel. Mater Today Bio 2021; 12:100138. [PMID: 34611622 PMCID: PMC8476776 DOI: 10.1016/j.mtbio.2021.100138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 09/02/2021] [Accepted: 09/05/2021] [Indexed: 01/08/2023] Open
Abstract
The versatile properties make hydrogels a potential multipurpose material that finds wide applications. However, the preparation of multipurpose hydrogels is very challenging. Here, we report a method based on free radical reaction and composite mechanisms to prepare mechanical and electrical self-healing multifunctional hydrogels. In this study, the introduction of imidazolium salt ionic liquids and glycerol in the hydrogel system endows the gels with good antibacterial, conductive, and adhesive properties and excellent antifreeze properties. The testing results show that the as-prepared hydrogel has stable mechanical and electrical properties even under the extremely cold condition of -50°C after self-healing. Moreover, the active esters formed in the dynamic radical reaction have better reducibility, thus further investing the as-prepared hydrogel with high antioxidant activity. The application results show that these comprehensive properties make such hydrogel system very useful in wound repair and wearable strain sensors.
Collapse
Affiliation(s)
- Y. Wang
- Key Laboratory of Advanced Technologies of materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| | - Y. Jia
- Key Laboratory of Advanced Technologies of materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
- Department of Electromechanical Engineering, Sichuan Engineering Technical College, Deyang, Sichuan, 618000, China
| | - H. Ren
- Key Laboratory of Advanced Technologies of materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| | - C. Lao
- Key Laboratory of Advanced Technologies of materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| | - W. Peng
- Department of Biochemistry and Molecular Biology, College of Basic and Forensic Medicine, Sichuan University, Chengdu, 610041, China
| | - B. Feng
- Key Laboratory of Advanced Technologies of materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| | - J. Wang
- Key Laboratory of Advanced Technologies of materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| |
Collapse
|
25
|
Li S, Wang Y, Cheng P, Feng B, Chen L, Wu K. Realization of Large Scale, 2D van der Waals Heterojunction of SnS 2 /SnS by Reversible Sulfurization. Small 2021; 17:e2101154. [PMID: 34331375 DOI: 10.1002/smll.202101154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 05/25/2021] [Indexed: 06/13/2023]
Abstract
2D van der Waals heterojunction provides an attractive opportunity for realizing novel electronic or optoelectronic devices. It remains challenging to realize high-quality heterostructures through scalable methods such as molecular epitaxy growth (MBE). Here, growth of few-layer SnS thin films is reported on mica and Nb-doped SrTiO3 (100) substrates by MBE. Then the top layer of SnS film is uniformly sulfurized to monolayer SnS2 in a sulfur atmosphere, resulting in a high-quality SnS2 /SnS 2D heterojunction. Furthermore, the SnS2 layer can be recovered to SnS by annealing SnS2 /SnS without sulfur supply, indicating the heterojunction formation is reversible. The scanning tunneling spectroscopy measurements on SnS2 /SnS heterostructure indicate the type-II band alignment in SnS2 /SnS. The work provides a promising approach to construct artificial 2D heterojunctions with desired properties, which could be extended to other sulfide and selenide systems.
Collapse
Affiliation(s)
- Shuhui Li
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Yu Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| |
Collapse
|
26
|
Foo M, See L, Lee J, Feng B, Kruger E. Current practices of Western Australian general dentists regarding management of patients on anticoagulant/antiplatelet therapy. Aust Dent J 2021; 66:385-390. [PMID: 34143428 DOI: 10.1111/adj.12863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 05/31/2021] [Accepted: 05/31/2021] [Indexed: 12/01/2022]
Abstract
PURPOSE Currently, there are little to no published studies outlining general dentists' knowledge in the management of patients on anticoagulant/antiplatelet therapies in Australia. The aim of this study was to investigate the current practices of Western Australian (WA) general dentists with regards to dental management of patients taking anticoagulants/antiplatelets. MATERIALS AND METHODS WA dentists were invited to undertake a survey to investigate their knowledge on the management of patients taking anticoagulant/antiplatelet. The questionnaire provided to WA general dentists consisted of pre-extraction advice on patients (direct oral anticoagulants [DOACs], antiplatelets, warfarin, dual antiplatelets and antiplatelet/anticoagulant). Results were analysed using descriptive statistics as well as chi-square tests. RESULTS Of the 89 participants, 40.5% had <5 years of general dental experience. Most WA general dentists (64%-71%) responded with 'no change' when performing extractions on patients on DOACs, antiplatelet therapy, warfarin, dual antiplatelets and antiplatelets/anticoagulants (P = 0.00). Furthermore, dentists with 6-10 years of experience were more likely to cease antiplatelet for 24 h before extractions (P < 0.05). Dentists who extracted 10-30 teeth per month were likely to stop antiplatelets and DOACs for more than 48 h compared to other groups (P < 0.05). CONCLUSION Most WA dentists would not cease anticoagulant/antiplatelet therapy when undergoing dental extractions.
Collapse
Affiliation(s)
- M Foo
- UWA Dental School, The University of Western Australia, Nedlands, Western Australia, Australia
| | - L See
- UWA Dental School, The University of Western Australia, Nedlands, Western Australia, Australia
| | - J Lee
- International Research Collaborative - Oral Health and Equity, The University of Western Australia, Crawley, Western Australia, Australia
| | - B Feng
- International Research Collaborative - Oral Health and Equity, The University of Western Australia, Crawley, Western Australia, Australia
| | - E Kruger
- International Research Collaborative - Oral Health and Equity, The University of Western Australia, Crawley, Western Australia, Australia
| |
Collapse
|
27
|
Hanczyc P, Rajchel-Mieldzioć P, Feng B, Fita P. Identification of Thioflavin T Binding Modes to DNA: A Structure-Specific Molecular Probe for Lasing Applications. J Phys Chem Lett 2021; 12:5436-5442. [PMID: 34080857 PMCID: PMC8280760 DOI: 10.1021/acs.jpclett.1c01254] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 05/24/2021] [Indexed: 05/17/2023]
Abstract
The binding mechanism of thioflavin T (ThT) to DNA was studied using polarized light spectroscopy and fluorescence-based techniques in solutions and in solid films. Linear dichroism measurements showed that ThT binds to DNA duplex by intercalation. Time-resolved fluorescence studies revealed a second binding mode which is the external binding to the DNA phosphate groups. Both binding modes represent the nonspecific type of interactions. The studies were complemented with the analysis of short oligonucleotides having DNA cavities. The results indicate that the interplay between three binding modes-intercalation, external binding, and binding inside DNA cavities-determines the effective fluorescence quantum yield of the dye in the DNA structures. External binding was found to be responsible for fluorescence quenching because of energy transfer between intercalated and externally bound molecules. Finally, amplified spontaneous emission (ASE) was successfully generated in the ThT-stained films and used for detecting different DNA structures. ASE measurements show that ThT-stained DNA structures can be used for designing bioderived microlasers.
Collapse
Affiliation(s)
- P. Hanczyc
- Institute
of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - P. Rajchel-Mieldzioć
- Institute
of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - B. Feng
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, 412 96 Gothenburg, Sweden
| | - P. Fita
- Institute
of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| |
Collapse
|
28
|
Penmetsa G, Pei S, Sauer B, Walsh JA, Feng B, Walker J, Douglas K, Clewell J. POS0262 IDENTIFYING EROSIVE DISEASE FROM RADIOLOGY REPORTS OF VETERANS WITH INFLAMMATORY ARTHRITIS USING NATURAL LANGUAGE PROCESSING. Ann Rheum Dis 2021. [DOI: 10.1136/annrheumdis-2021-eular.1794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Background:The presence of erosive disease influences diagnosis, management, and prognosis in inflammatory arthritis (IA).Research of IA in large datasets is limited by a lack of methods for identifying erosions.Objectives:To develop methods for identifying articular erosions in radiology reports from veterans with IA.Methods:Included veterans had ≥2 ICD codes for ankylosing spondylitis (AS), psoriatic arthritis (PsA), or rheumatoid arthritis (RA) between 2005- 2019, in Veterans Affairs Corporate Data Warehouse. Chart review & annotation of radiology notes produced the reference standard, & identified erosion terms that informed classification rule development. A rule-based natural language processing (NLP) model was created & revised in training snippets. The NLP method was validated in an independent reference sample of IA patients at the snippet & patient levelsStepDescriptionNumber & example1 Radiology notesa.Select note titles potentially relevant to IAa. 35,141 notes titlesb.Extract notes with titles potentially related to IAb. 2,926,113 radiology notes2 Possible meaningful termsa.Compile list of root terms that may indicate erosiona. 11 root terms (i.e. ero*, pencil*cup, irreg*)b.Query radiology notes for root term variationsb. 1178 variations (i.e. erosion, erotic, erode)c.Select possible meaningful termsc. 179 possible terms (i.e. erosion, erode)3 Annotationa.Extract snippets^ containing possible meaningful termsa.5000 snippets from radiology notesb.Classify snippets according to: 1) Meaningful term, 2) Relevance to joint, 3) Attribution to IA, 4) Affirmationb.4068 classifications with 1017 snippets (in rounds of 50-417 snippets for NLP training & testing)4 Rule developmenta.Identify meaningful terms representing erosiona. 6 terms (pencil * cup, erosion, erosive, etc.)b.Exclude erosive processes irrelevant to joint(s)b. 28 irrelevant processes (i.e. gastric erosion)c. Exclude articular erosive processes not attributed to IAc. 5 non-IA processes IA (i.e. infection)d. Classify as affirmed/negated (erosion present/absent)d. 83 affirmation/negation rules5 NLP trainingDesign & revise NLP model until accuracy ≥90%6 rounds, 817 snippets (AS 417, RA 200, PsA 200)6 NLP testingTest NLP model200 snippets (AS 100, RA 50, PsA 50)7 Pt classificationa. Develop rules for classifying pts with discordant snippetsa. 5 rules developed in 368 ptsb. Build reference sample (pts classified as erosive or non-erosive via chart review)b. 30 IA pts (10 AS, 10 RA, 10 PsA)8 NLP validationValidate NLP model in reference sample at snippet level149 snippets (29 AS, 76 RA, 44 PsA)9 Method validationValidate methods (NLP+pt classification) at pt level30 IA pts (reference sample)pt= patient. ^Snippets include text containing 30 words before & after meaningful termsResults:In 168,667 veterans with IA, the mean age was 63.1 & 90.3% were male. Method development involved radiology note & erosion term selection, rule development, NLP model building, & method validation. The NLP model accuracy was 94.6% at the snippet level & 90.0% at the patient level, for all IA patients.Accuracy of methods.Conclusion:The methods accurately identify erosions from radiology reports of veterans with IA. They may facilitate a broad range of research involving cohort identification & disease severity stratificationReferences:[1]Walsh JA, et al. J Rheumatol. 2020;47(1):42-49Disclosure of Interests:Gopi Penmetsa: None declared, Shaobo Pei: None declared, Brian Sauer Grant/research support from: I have been an investigator on research contracts supported by Abbvie., Jessica A. Walsh Consultant of: AbbVie, Amgen, Janssen, Lilly, Novartis, Pfizer, UCB, Grant/research support from: AbbVie, Merck, Pfizer, Bingjian Feng Grant/research support from: Bing-Jian Feng reports funding and sponsorship to his institution on his behalf from Pfizer Inc., Regeneron Genetics Center LLC, and Astra Zeneca (UK). The PERCH software, for which Bing-Jian Feng is the inventor, has been non-exclusively licensed to Ambry Genetics for clinical genetic testing services and research., Jodi Walker Shareholder of: Abbvie and mutual funds containing various pharmaceutical companies, Employee of: Abbvie, Kevin Douglas Shareholder of: employed by Abbvie, Employee of: employed by Abbvie, Jerry Clewell Shareholder of: Own Abbvie Shares and mutual funds that hold pharmaceutical and other health care stocks, Employee of: I am current Abbvie Inc employee and past employee of Eli Lilly co
Collapse
|
29
|
Zhu YJ, Feng B, Wang BZ, Wang S, Ye F, Ma XH, Zhao XM. [Value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid enhanced magnetic resonance imaging and diffusion-weighted MR imaging in predicting microvascular invasion in hepatocellular carcinoma and the prognostic significance]. Zhonghua Zhong Liu Za Zhi 2021; 43:312-317. [PMID: 33752311 DOI: 10.3760/cma.j.cn112152-20191009-00652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the combined value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in predicting pathological microvascular invasion (pMVI) preoperatively, and to determine the relationship between prediction results and prognosis in hepatocellular carcinoma (HCC) patients. Methods: A total of 181 newly diagnosed HCC patients were enrolled in this study. Imaging characteristics and the apparent diffusion coefficient (ADC) value of DWI were analyzed. The differences of imaging characteristics and ADC values between different pMVI groups were analyzed.Multivariate logistic regression and receiver operating characteristic (ROC) curve were used to analyze the value for pMVI prediction by using significant parameters. The patients were grouped based on MRI predicted MVI (mrMVI), and the relationship between mrMVI and recurrence free survival time (RFS) was analyzed. Results: Fifty-one patients were pMVI positive and 130 patients were pMVI negative. The ADC value in pMVI positive group were (1.10±0.17)×10(-3) mm(2)/s, significantly lower than (1.27±0.22)×10(-3) mm(2)/s of pEMVI negative group (P<0.001). The incidence rates of incomplete enhancing "capsule" , non-smooth tumor margin, arterial peritumoral enhancement, mosaic architecture and peritumoral hypointensity on hepatobiliary phase (HBP) in pMVI positive group were significantly higher than those of negative group (all P<0.05). Multivariate logistic regression analysis showed that tumor margin, arterial peritumoral enhancement, peritumoral hypointensity on HBP and ADC value were independently associated with pMVI. ROC analysis showed that the area under curve, sensitivity and specificity of pMVI predicted by combined parameters were 0.830, 76.5% and 81.5%, respectively. The median RFS of mrMVI positive group was 23.6 months, significantly lower than 38.2 months of mrEMVI negative group (P=0.004). Conclusion: Tumor margin, arterial peritumoral enhancement, peritumoral hypointensity on HBP and ADC value are independent predictors of pMVI in HCC, and mrMVI is related with RFS.
Collapse
Affiliation(s)
- Y J Zhu
- Department of Imaging Diagnosis, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - B Feng
- Department of Imaging Diagnosis, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - B Z Wang
- Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - S Wang
- Department of Imaging Diagnosis, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - F Ye
- Department of Imaging Diagnosis, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - X H Ma
- Department of Imaging Diagnosis, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - X M Zhao
- Department of Imaging Diagnosis, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| |
Collapse
|
30
|
Kang FM, Shan YL, Feng B, Wang ZX. [An investigation of musculoskeletal disorders at multiple sites and related influencing factors among workers in an automobile assembly shop]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2021; 39:40-43. [PMID: 33535339 DOI: 10.3760/cma.j.cn121094-20191114-00528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the current status of work-related musculoskeletal disorders (WMSDs) in automobile assembly workers, as well as the distribution of WMSDs at multiple sites and related influencing factors. Methods: From March to July 2019, cluster sampling was performed to select 663 male automobile assembly workers as respondents, and the musculoskeletal injury questionnaire was used to investigate their general status and working condition. A multinomial logistic regression analysis was used to analyze the influencing factors for WMSDs at multiple sites. Results: The detection rate of WMSDs within the past 7 days was 37.9% (251/663) among the automobile assembly workers, and the detection rate of WMSDs within the past 1 year was 51.9% (344/663) . Of all workers, 13.6% (90/663) had WMSDs involving only 1 site, while 38.3% (254/663) had WMSDs involving 2 or more sites. The multinomial logistic regression analysis showed that frequent turns during work was a risk factor for WMSDs involving 1-3, 4-6, and 7-9 sites (odds ratio [OR]=1.65, 2.47, and 3.65, respectively) . Repeated action of lower extremities and ankles was a risk factor for WMSDs involving 4-6 and 7-9 sites (OR=2.15 and 2.98, respectively) . Working in an uncomfortable position was a risk factor for WMSDs involving 1-3, 4-6, and 7-9 sites (OR=1.95, 2.67, and 3.04, respectively) . Prolonged standing during work was a risk factor for WMSDs involving 1-3 and 4-6 sites (OR= 1.87 and 1.79, respectively) . Working overtime was a risk factor for WMSDs involving 7-9 sites (OR=5.48) . Adequate time for rest was a protective factor against WMSDs involving 1-3 and 4-6 sites (OR=0.50 and 0.31, respectively) . Conclusion: There is a high detection rate of WMSDs in automobile assembly workers, and WMSDs at multiple sites are more common than WMSDs at a single site. Poor position and organizational management factors are risk factors for occupational WMSDs at multiple sites.
Collapse
Affiliation(s)
- F M Kang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University (Shandong Academy of Medical Sciences), Jinan 250000, China
| | - Y L Shan
- Shandong Academy of Occupational Health and Occupational Medicine, Jinan 250000, China
| | - B Feng
- Shandong Academy of Occupational Health and Occupational Medicine, Jinan 250000, China
| | - Z X Wang
- National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention Beijing 100050, China
| |
Collapse
|
31
|
Zhao Y, Siri S, Feng B, Pierce DM. Computational Modeling of Mouse Colorectum Capturing Longitudinal and Through-thickness Biomechanical Heterogeneity. J Mech Behav Biomed Mater 2021; 113:104127. [PMID: 33125950 PMCID: PMC8053306 DOI: 10.1016/j.jmbbm.2020.104127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 09/03/2020] [Accepted: 10/01/2020] [Indexed: 12/19/2022]
Abstract
Mechanotransduction, the encoding of local mechanical stresses and strains at sensory endings into neural action potentials at the viscera, plays a critical role in evoking visceral pain, e.g., in the distal colon and rectum (colorectum). The wall of the colorectum is structurally heterogeneous, including two major composites: the inner consists of muscular and submucosal layers, and the outer consists of circular muscular, intermuscular, longitudinal muscular, and serosal layers. In fact the colorectum presents biomechanical heterogenity across both the longitudinal and through-thickness directions thus highlighting the differential roles of sensory nerve endings within different regions of the colorectum in visceral mechanotransduction. We determined constitutive models and model parameters for individual layers of the colorectum from three longitudinal locations (colonic, intermediate, and distal) using nonlinear optimization to fit our experimental results from biaxial extension tests on layer-separated colorectal tissues (mouse model, 7×7 mm2, Siri et al., Am. J. Physiol. Gastrointest. Liver Physiol. 316, G473-G481 and 317, G349-G358), and quantified the thicknesses of the layers. In this study we also quantified the residual stretches stemming from separating colorectal specimens into inner and outer composites and we completed new pressure-diameter mechanical testing to provide an additional validation case. We implemented the constitutive equations and created two-layered, 3-D finite element models using FEBio (University of Utah), and incorporated the residual stretches. We validated the modeling framework by comparing FE-predicted results for both biaxial extension testing of bulk specimens of colorectum and pressure-diameter testing of bulk segments against corresponding experimental results independent of those used in our model fitting. We present the first theoretical framework to simulate the biomechanics of distal colorectum, including both longitudinal and through-thickness heterogeneity, based on constitutive modeling of biaxial extension tests of colon tissues from mice. Our constitutive models and modeling framework facilitate analyses of both fundamental questions (e.g., the impact of organ/tissue biomechanics on mechanotransduction of the sensory nerve endings, structure-function relationships, and growth and remodeling in health and disease) and specific applications (e.g., device design, minimally invasive surgery, and biomedical research).
Collapse
Affiliation(s)
- Y Zhao
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA; Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - S Siri
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - B Feng
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - D M Pierce
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA; Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA.
| |
Collapse
|
32
|
Feng B, Fei T, Shaver D, Jung Y, Fang J, Rahaman R, Lee C, Smith M, Shemon E. MULTIPHYSICS MODELING OF PRECURSORS IN MOLTEN SALT FAST REACTORS USING PROTEUS AND Nek5000. EPJ Web Conf 2021. [DOI: 10.1051/epjconf/202124706026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The goal of this work was to calculate the impact of the delayed neutron precursor drift in fast spectrum Molten Salt Reactors (MSRs) using coupled solutions from the neutronics code PROTEUS and the computational fluid dynamics code Nek5000. Specifically, using a multiphysics approach to solve the effective delayed neutron fraction (βeff) or delayed neutron precursor distribution for reactors with flowing fuel salts would provide valuable information for transient simulations and safety assessments. Given the multiple options for the flux solution and geometric resolution/fidelity in PROTEUS, two approaches were developed and applied to various test cases: PROTEUS-NODAL/Nek5000 and PROTEUS-SN/Nek5000. For the former, the precursors are tracked in the built-in precursor drift model in PROTEUS-NODAL, whereas in the latter, Nek5000 directly tracks the precursors. Both approaches were used to solve a single test channel problem and showed excellent agreement in the calculated βeff. Separately, a 3D hourglass-shaped core was modeled using the PROTEUS-SN/Nek5000 approach. This problem was designed to demonstrate the capability of the discrete ordinates (SN) solver and Nek5000 to model complex core designs with axially varying geometries and the ability for Nek5000 to track the precursors and calculate the resulting βeff. In addition, the Nek5000 calculations revealed the presence of recirculation zones in the hourglass design, which could lead to significant temperatures in the fuel salt and surrounding materials. These first coupled solutions show why these approaches may be necessary for not only predicting the precursor drift effect in fast MSRs but also for reactor design and performance assessments.
Collapse
|
33
|
Richards S, Feng B. Application of sensitivity analysis in DYMOND/Dakota to fuel cycle transition scenarios. EPJ Nuclear Sci Technol 2021. [DOI: 10.1051/epjn/2021024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The ability to perform sensitivity analysis has been enabled for the nuclear fuel cycle simulator DYMOND through its coupling with the design and analysis toolkit Dakota. To test and demonstrate these new capabilities, a transition scenario and multi-parameter study were devised. The transition scenario represents a partial transition from the US nuclear fleet to a closed fuel cycle with small modular LWRs and fast reactors fueled by reprocessed used nuclear fuel. Four uncertain parameters in this transition were studied – start date of reprocessing, total reprocessing capacity, the nuclear energy demand growth, and the rate at which the fast reactors are deployed – with respect to their impact on four response metrics. The responses – total natural uranium consumed, maximum annual enrichment capacity required, total disposed mass, and total cost of the nuclear fuel cycle – were chosen based on measures known to be of interest in transition scenarios [2] and to be significantly impacted by the varying parameters. Analysis of this study was performed both from the direct sampling and through surrogate models developed in Dakota to calculate the global sensitivity measures Sobol’ indices. This example application of this new capability showed that the most consequential parameter to most metrics was the share of new build capacity that is fast reactors. However, for the cost metric, the scaling factor of the energy demand growth was significant and had synergistic behavior with the fast reactor new build share.
Collapse
|
34
|
Abstract
In recent years, there has been renewed interest in Molten Salter Reactors (MSRs) for their potential advantages compared to reactors that rely on solid fuel. In response to such interest, the System Analysis Module (SAM) was enhanced to include MSR-specific modeling features including a delayed neutron precursor drift model and a modified point kinetics model. This paper discusses the validation of these features using the experiments conducted in the Molten Salt Reactor Experiment (MSRE). These experiments include the pump start-up and coast-down tests at zero power and a thermal convection test. For the zero power tests, the change in pump speeds induces flow rate changes in the core that impact the precursor concentrations. This introduces a neutron imbalance and requires the adjustment of the control rods to counter-balance this effect. SAM was used to evaluate the precursor concentration in the core as a function of time, and the resulting changes in reactivity were evaluated through the modified point kinetics equation. The results show good agreement with the experimental data. It should be noted that the pump performance curve used in this analysis was re-constructed based on the initial water test data of the fuel pump. The steady-state pump curve is assumed to be applicable to transient flow operations. The thermal convection test was conducted by shutting off the pumps, reducing the inlet core temperature for 360 minutes, and allowing the power to be adjusted by the inherent feedbacks of the system. The power level during this transient was evaluated by SAM as a function of time.
Collapse
|
35
|
Han HQ, Ou JJ, Feng B, Deng W, Jiang QY, Huang Y, Zhang QF, Zheng WQ. [Application value of urinary IGFBP7 and TIMP-2 in acute kidney injury with decompensated hepatitis B virus-related liver cirrhosis]. Zhonghua Gan Zang Bing Za Zhi 2020; 28:760-765. [PMID: 33053976 DOI: 10.3760/cma.j.cn501113-20190215-00048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the application value of new urinary biomarkers insulin-like growth factor binding protein 7 (IGFBP7) and tissue matrix metalloproteinase inhibitor-2 (TIMP-2) in acute kidney injury with decompensated hepatitis B virus-related liver cirrhosis. Methods: 45 newly hospitalized cases with decompensated hepatitis B virus-related liver cirrhosis were selected. Among them, 19 cases were combined with AKI on admission (cirrhosis-AKI group), 26 cases without AKI (cirrhosis-non-AKI group), and 12 healthy cases (normal control group). First-morning urine samples were collected and IGFBP7 and TIMP-2 were detected by enzyme-linked immunosorbent assay (ELISA). Urinary IGFBP7 and serum creatinine (SCr) were dynamically monitored after hospitalization in cirrhosis-non-AKI group. Normally distributed measurement data were compared by t-test, and non-normally distributed measurement data were compared by rank sum test. The receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to evaluate the diagnostic accuracy of the indicators. Results: Urinary IGFBP7, IGFBP7 with TIMP-2 (IGFBP7×TIMP-2) in cirrhosis-AKI group (n = 19) were equally higher than that of the cirrhosis-non-AKI group (P < 0.05). Urinary IGFBP7, TIMP-2 and IGFBP7×TIMP-2 in cirrhosis-AKI group or cirrhosis-non-AKI group were significantly higher than those of the normal control group (P < 0.01). The AUC of urinary IGFBP7 and urinary IGFBP7×TIMP-2 for diagnosis of AKI were 0.703 (95% CI 0.547-0.860) and 0.700 (95% CI 0.541-0.859), respectively. In the liver cirrhosis-non-AKI group (n = 26), 5 cases of AKI were newly diagnosed according to the changes in SCr during hospitalization (progressive group). Urinary IGFBP7 was significantly increased 2 days before the diagnosis of AKI. The concentration of urinary IGFBP7 at admission in the progressive group (n = 5) was higher than that of the non-progressive group (n = 21) (P < 0.05). Conclusion: Urinary IGFBP7 and TIMP-2 concentrations were significantly increased in patients with decompensated hepatitis B virus-related liver cirrhosis. When AKI occurred, urinary IGFBP7 and IGFBP7×TIMP-2 was further increased. Urinary IGFBP7 is valuable for early AKI diagnosis, and may play a role in predicting AKI occurrence.
Collapse
Affiliation(s)
- H Q Han
- Infectious Diseases Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - J J Ou
- Department Digestive Internal, Xiangtan Central Hospital, Xiangtan, Hunan 411100, China
| | - B Feng
- Infectious Diseases Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - W Deng
- Infectious Diseases Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Q Y Jiang
- Infectious Diseases Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Y Huang
- Infectious Diseases Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Q F Zhang
- Infectious Diseases Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - W Q Zheng
- Infectious Diseases Center, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| |
Collapse
|
36
|
Wang Y, Kong L, Chen C, Cheng P, Feng B, Wu K, Chen L. Realization of Regular-Mixed Quasi-1D Borophene Chains with Long-Range Order. Adv Mater 2020; 32:e2005128. [PMID: 33118245 DOI: 10.1002/adma.202005128] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/29/2020] [Indexed: 06/11/2023]
Abstract
The polymorphism of borophene makes it a promising system to realize tunable physical or chemical properties. Various pure borophene phases consisting of quasi-1D boron chains with different widths have been commonly obtained in experimental studies. Here, it is shown that, due to a substrate mediation effect, artificial long-range ordered phases of borophene consisting of different combinations of boron chains seamlessly joined together can be achieved on Ag(100). Scanning tunneling microscopy measurements and theoretical calculations reveal that mixed-chain phases are more stable than the pure phase, and interact only weakly with the substrate. The mixed-chain phases with various proportions of different chains can be well separated based on the crystal direction of the substrate. The successful growth of mixed-chain phases is expected to deepen the impact of substrate tailored synthesis of borophene.
Collapse
Affiliation(s)
- Yu Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Longjuan Kong
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- School of Physics, Nankai University, Tianjin, 300071, China
| | - Caiyun Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, 523808, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, 523808, China
| |
Collapse
|
37
|
Zhang H, Cao X, Wang D, Xin H, Liu Z, Yan J, Feng B, Quan Z, Du Y, Liu J, Guan L, Shen F, Guan X, Jin Q, Pan S, Gao L. The acquisition of Mycobacterium tuberculosis infection in village doctors in China: a prospective study. Int J Tuberc Lung Dis 2020; 24:1241-1246. [PMID: 33317666 DOI: 10.5588/ijtld.20.0153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND: Occupational exposure-related risk of Mycobacterium tuberculosis infection has been reported for village doctors in China. This prospective study aims to estimate the infection acquisition in this key population.METHODS: At baseline, all village doctors registered in Zhongmu County were tested by QuantiFERON®-TB Gold In-Tube (QFT) and QuantiFERON®-TB Gold Plus (QFT-Plus) in parallel. Those negatives for either of the tests were retested to identify conversions at the 2-year follow-up investigation.RESULTS: A total of 367 eligible participants completed the 2-year follow-up survey with frequency of conversion of 5.0% (18/361) for QFT and 6.1% (21/343) for QFT-Plus. The agreement of follow-up results between the tests was 93.2% with a κ coefficient of 0.43 (95%CI 0.20-0.65). Among QFT-Plus convertors, the difference between TB1 and TB2 tubes (TB2-TB1) was significantly increased as compared with baseline results (P = 0.039). Participants from the villages with occurrence of microbiologically confirmed pulmonary TB showed higher frequency of QFT conversions (11.0% vs. 3.2%, P = 0.011) and QFT-Plus conversions (12.3% vs. 4.4%, P = 0.027) than those from the villages without occurrence.CONCLUSION: Our results consistently suggest that capability on occupational protection and M. tuberculosis infection control should be improved in village doctors in China.
Collapse
Affiliation(s)
- H Zhang
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - X Cao
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - D Wang
- Center for Disease Prevention and Control of Zhongmu County, Zhengzhou
| | - H Xin
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Z Liu
- Center for Disease Prevention and Control of Zhongmu County, Zhengzhou
| | - J Yan
- Center for Disease Prevention and Control of Zhongmu County, Zhengzhou
| | - B Feng
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Z Quan
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Y Du
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - J Liu
- The Sixth People´s Hospital of Zhengzhou, Zhengzhou, China
| | - L Guan
- The Sixth People´s Hospital of Zhengzhou, Zhengzhou, China
| | - F Shen
- The Sixth People´s Hospital of Zhengzhou, Zhengzhou, China
| | - X Guan
- The Sixth People´s Hospital of Zhengzhou, Zhengzhou, China
| | - Q Jin
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - S Pan
- Center for Disease Prevention and Control of Zhongmu County, Zhengzhou
| | - L Gao
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| |
Collapse
|
38
|
Zhang SH, Zhang ZH, Tao L, Feng B, Wang H, Zhang HD, Zhang P. [Investigation on occupational hazards in a refrigeration equipment manufacturing enterprise]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2020; 38:708-711. [PMID: 33036541 DOI: 10.3760/cma.j.cn121094-20190716-00304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the distribution and intensity of noise and ultraviolet radiation of welding posts in a refrigeration equipment manufacturing enterprise, in conjunction with the health status of welding workers, providing scientific evidence for the prevention and control of occupational diseases in this type of post. Methods: In May 2019, a cross-sectional survey method was used to select 576 welding workers in the pressure vessel workshop and the unit assembly workshop of a refrigeration complete equipment manufacturer from 2016 to 2018 as the research objects. The occupational hygiene survey and occupational hazard factor measurement were carried out in the workplace, and the measurement data and occupational health examination results were statistically analyzed. Results: The over standard rate of individual Lex in pressure vessel workshop was 82.2% (37/45) . Compared with the unit assembly workshop, the individual Lex of welding workers in pressure vessel workshop was higher than that in unit assembly workshop (t=13.43, P= 0.00) ; the effective irradiance exceeding rate of welding workers in pressure vessel workshop and unit assembly workshop was 33.3% (4/12) and 25.0% (3/12) , The meacurement of ovradiation in the moskment the occupational exposure limit. The deaf rate and hearing loss rate in pressure vessel workshop were 1.5% (5/336) 20.5% (69/336) , respectively, significantly higher than that in umit assembly workshop (P<0.05) . The detection rate of hearing loss of pressure vessel workshop workers increased year by year, and the difference was statistically significant (χ(2trend)=22.42, P<0.01) ; compared with the unit assembly workshop from 2016 to 2018, the detection rates of lens opacity, corneal cloudiness and hearing loss of pressure vessel workshop workers were statistically significant (χ(2)=9.45, 14.80, 55.99, P<0.01) . Conclusion: Welding workers exposed to noise and ultraviolet radiation are easy to be ignored. The enterprise management department should attach great importance to it and take comprehensive measures to protect the health of welding workers.
Collapse
Affiliation(s)
- S H Zhang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250002, China
| | - Z H Zhang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250002, China
| | - L Tao
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250002, China
| | - B Feng
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250002, China
| | - H Wang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250002, China
| | - H D Zhang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250002, China
| | - P Zhang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250002, China
| |
Collapse
|
39
|
Dixon B, Hoffman E, Feng B, Davidson E, Hays R, Worrall A, Hansen J, Fei T, Hiruta H, Peterson-Droogh J, Ganda F, Betzler B, Kim T, Taiwo T. Reassessing methods to close the nuclear fuel cycle. ANN NUCL ENERGY 2020. [DOI: 10.1016/j.anucene.2020.107652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
40
|
Yang PY, Li PC, Feng B. Protective effects of gliclazide on high glucose and AGEs-induced damage of glomerular mesangial cells and renal tubular epithelial cells via inhibiting RAGE-p22phox-NF-kB pathway. Eur Rev Med Pharmacol Sci 2020; 23:9099-9107. [PMID: 31696501 DOI: 10.26355/eurrev_201910_19313] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Gliclazide is one of the most widely used therapeutic drugs for diabetes. As a second-generation sulfonylurea oral hypoglycemic drug, it can lower blood glucose level and delay the occurrence and development of diabetic nephropathy (DN). However, the underlying mechanism remains unclear. Therefore, the aim of this study was to explore whether gliclazide had protective effects on high glucose and advanced glycation end products (AGEs)-induced injury of human mesangial cells (HMCs) and renal tubular epithelial cells. MATERIALS AND METHODS HMC and renal tubular epithelial cell lines [human kidney 2 (HK-2)] were cultured in vitro. All cells were then divided into the follow groups: 1) blank control group (5.6 mmol/L glucose), 2) AGEs group [400 μg/mL AGE-bovine serum albumin (AGE-BSA)], 3) high glucose group (25 mmol/L glucose), 4) gliclazide + AGEs group (400 μg/mL AGE-BSA + 20 μmol/L gliclazide) and 5) gliclazide + high glucose group (25 mmol/L glucose + 20 μmol/L gliclazide). Cell counting kit-8 (CCK-8) assay was adopted to determine cell viability. Flow cytometry was used to detect cell apoptosis. The levels of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured as well. Furthermore, the mRNA expressions of receptor for AGE (RAGE), p22phox and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were measured via fluorescence quantitative Real-time polymerase chain reaction (qRT-PCR). RESULTS Compared with control group, significantly accelerated apoptosis of HMCs and HK-2, increased MDA level, decreased SOD and GSH-Px levels, and up-regulated mRNA expressions of RAGE, p22phox and NF-κB were observed in HMCs and HK-2 of high glucose group and AGEs group. Meanwhile, there were obviously alleviated apoptosis of HMCs and HK-2, decreased MDA level, increased SOD and GSH-Px levels, as well as down-regulated mRNA expressions of RAGE, p22phox and NF-κB in HMCs and HK-2 of gliclazide group compared with high glucose and AGEs group. Furthermore, significant correlations were found between the mRNA expression of RAGE and the apoptosis rate of HMCs and HK-2 (HMCs: r=0.701, p=0.004 and HK-2: r=0.633, p=0.011). CONCLUSIONS Gliclazide has protective effects on high glucose and AGEs-induced damage of glomerular mesangial cells and renal tubular epithelial cells via inhibiting RAGE-NADPH oxidase-NF-kB pathway.
Collapse
Affiliation(s)
- P-Y Yang
- Department of Endocrinology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China.
| | | | | |
Collapse
|
41
|
|
42
|
Cao SL, Ren Y, Li Z, Lin J, Weng XS, Feng B. Clinical effectiveness of 3 days preoperative treatment with recombinant human erythropoietin in total knee arthroplasty surgery: a clinical trial. QJM 2020; 113:245-252. [PMID: 31605493 DOI: 10.1093/qjmed/hcz261] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 08/23/2019] [Indexed: 12/19/2022] Open
Abstract
AIMS The purpose of study is to evaluate the effect and complication of preoperative short-term daily recombinant human erythropoietin (rhEPO) treatment for blood-saving in patients undergoing unilateral primary total knee arthroplasty (TKA). METHODS This three-arm randomized clinical trial compared three different rhEPO-based treatment protocols for unilateral primary TKA. Group A: application of daily doses of rhEPO combined with iron supplement starting 3 days before surgery; Group B: application of daily doses of rhEPO combined with iron supplement starting the day of surgery; Group C: iron supplement alone. Perioperative hemoglobin (Hb) level gaps, total perioperative blood loss, reticulocyte levels and treatment-related complications were studied. RESULTS A total of 102 patients were included (35, 35 and 32 patients in Groups A, B and C, respectively). Total blood loss (TBL) in Groups A, B and C was 490.84, 806.76 and 924.21 ml, respectively. Patients in Group A had a significant lower TBL than Groups B and C (A vs. B: P = 0.010; A vs. C: P < 0.001). There was no difference as for TBL between Groups B and C (P = 0.377). Group A patients had significant smaller Hb decline than Group C on the third and fifth postoperative day (P = 0.049, P = 0.037), as well as than Group B on the fifth postoperative day (P = 0.048). There was no difference as for Hb decline between Groups B and C. No difference was shown in levels of inflammatory biomarkers or blood-saving protocol-related complications among three groups. CONCLUSIONS Daily dose of rhEPO combined with iron supplement administered 3 days before TKA procedures could significantly decrease perioperative blood loss and improve postoperative Hb levels, without significantly elevating risks of complication, when compared with admission of rhEPO on the day of surgery and iron supplement alone. Preoperative daily rhEPO treatment could be a more effective blood-saving protocol in TKA procedures.
Collapse
Affiliation(s)
- S-L Cao
- Department of Orthopaedic Surgery, Peking Union Medical College, Beijing 100730, China
| | - Y Ren
- Department of Orthopaedic Surgery, Peking Union Medical College, Beijing 100730, China
| | - Z Li
- Department of Orthopaedic Surgery, Peking Union Medical College, Beijing 100730, China
| | - J Lin
- Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College, Beijing 100730, China
| | - X-S Weng
- Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College, Beijing 100730, China
| | - B Feng
- Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College, Beijing 100730, China
| |
Collapse
|
43
|
Eakin C, Sun K, Shan M, Zhou Y, Feng B, Wang S, Posey J, Rubio M, Garg K, Thress K, Wang J, Monk B. The Presence of Circulating Tumor DNA in Ovarian Cancer Patients After Platinum-Based Chemotherapy. Gynecol Oncol 2020. [DOI: 10.1016/j.ygyno.2019.11.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
44
|
Ito S, Arita M, Haruyama J, Feng B, Chen WC, Namatame H, Taniguchi M, Cheng CM, Bian G, Tang SJ, Chiang TC, Sugino O, Komori F, Matsuda I. Surface-state Coulomb repulsion accelerates a metal-insulator transition in topological semimetal nanofilms. Sci Adv 2020; 6:eaaz5015. [PMID: 32219169 PMCID: PMC7083614 DOI: 10.1126/sciadv.aaz5015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 12/30/2019] [Indexed: 06/10/2023]
Abstract
The emergence of quantization at the nanoscale, the quantum size effect (QSE), allows flexible control of matter and is a rich source of advanced functionalities. A QSE-induced transition into an insulating phase in semimetallic nanofilms was predicted for bismuth a half-century ago and has regained new interest with regard to its surface states exhibiting nontrivial electronic topology. Here, we reveal an unexpected mechanism of the transition by high-resolution angle-resolved photoelectron spectroscopy combined with theoretical calculations. Anomalous evolution and degeneracy of quantized energy levels indicate that increased Coulomb repulsion from the surface states deforms a quantum confinement potential with decreasing thickness. The potential deformation strongly modulates spatial distributions of quantized wave functions, which leads to acceleration of the transition beyond the original QSE picture. This discovery establishes a complete picture of the long-discussed transition and highlights a new class of size effects dominating nanoscale transport in systems with metallic surface states.
Collapse
Affiliation(s)
- S. Ito
- Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwa, Chiba, Japan
| | - M. Arita
- Hiroshima Synchrotron Radiation Center (HSRC), Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - J. Haruyama
- Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwa, Chiba, Japan
| | - B. Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - W.-C. Chen
- Department of Physics and Astronomy, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - H. Namatame
- Hiroshima Synchrotron Radiation Center (HSRC), Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - M. Taniguchi
- Hiroshima Synchrotron Radiation Center (HSRC), Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - C.-M. Cheng
- National Synchrotron Radiation Research Center (NSRRC), Hsinchu, Taiwan, Republic of China
| | - G. Bian
- Department of Physics and Astronomy, University of Missouri, Columbia, MO, USA
| | - S.-J. Tang
- Department of Physics and Astronomy, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
- National Synchrotron Radiation Research Center (NSRRC), Hsinchu, Taiwan, Republic of China
| | - T.-C. Chiang
- Department of Physics and Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - O. Sugino
- Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwa, Chiba, Japan
| | - F. Komori
- Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwa, Chiba, Japan
| | - I. Matsuda
- Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwa, Chiba, Japan
| |
Collapse
|
45
|
Zhao Y, Feng B, Lee J, Lu N, Pierce DM. A multi-layered model of human skin elucidates mechanisms of wrinkling in the forehead. J Mech Behav Biomed Mater 2020; 105:103694. [PMID: 32090898 DOI: 10.1016/j.jmbbm.2020.103694] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 01/20/2020] [Accepted: 02/09/2020] [Indexed: 12/18/2022]
Abstract
Skin wrinkling, especially in the facial area, is a prominent sign of aging and is a growing area of research aimed at developing cosmetics and dermatological treatments. To better understand and treat undesirable skin wrinkles, it is vitally important to elucidate the underlying mechanisms of skin wrinkling, a largely mechanical process. Human skin, a multi-layer composite, has six mechanically distinct layers: from the outermost inward they are the stratum corneum, viable epidermis, dermal-epidermal-junction, papillary dermis, reticular dermis, and hypodermis. To better address the through-thickness hierarchy, and the development of wrinkling within this complicated hierarchy, we established a six-layered model of human skin realized with finite element modeling, by leveraging available morphological and biomechanical data on human skin of the forehead. Exercising our new model we aimed to quantify the effects of three potential mechanisms of wrinkle formation: (1) skin compression due to muscle contraction (dynamic wrinkles); (2) age-related volumetric tissue loss (static wrinkles); and (3) the combined effects of both mechanisms. Since hydration of the stratum corneum significantly affects its stiffness we also aimed to quantify the influence its hydration with these three potential mechanisms of wrinkle formation. Our six-layered skin model, combined with the proposed wrinkling mechanisms, successfully predicts the formation of dynamic and static wrinkles in the forehead consistent with the experimental literature. We observed three wrinkling modes in the forehead where the deepest wrinkles could reach to the reticular dermis. With further refinement our new six-layered model of human skin can be applied to study other region-specific wrinkle types such as the "crow's feet" and the nasolabial folds.
Collapse
Affiliation(s)
- Y Zhao
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA
| | - B Feng
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - J Lee
- Unilever Research and Development, Trumbull, CT, USA
| | - N Lu
- Unilever Research and Development, Trumbull, CT, USA
| | - D M Pierce
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA; Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA.
| |
Collapse
|
46
|
Xin H, Cao X, Zhang H, Liu J, Pan S, Li X, Guan L, Shen F, Liu Z, Wang D, Guan X, Yan J, Li H, Feng B, Zhang M, Yang Q, Jin Q, Gao L. Dynamic changes of interferon gamma release assay results with latent tuberculosis infection treatment. Clin Microbiol Infect 2020; 26:1555.e1-1555.e7. [PMID: 32062048 DOI: 10.1016/j.cmi.2020.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/02/2020] [Accepted: 02/08/2020] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Using QuantiFERON-TB Gold In-Tube (QFT-GIT) for monitoring tuberculosis (TB) and latent TB infection treatment effect is controversial. The present study aimed to evaluate the dynamic changes of interferon gamma (IFN-γ) levels along with latent TB infection treatment via a randomized controlled study. METHODS A total of 910 participants treated with 8 weeks of once-weekly rifapentine plus isoniazid (group A), 890 treated with 6 weeks of twice-weekly rifapentine plus isoniazid (group B) and 818 untreated controls (group C) were followed for 2 years to track active TB development. QFT-GIT tests were repeated three times for all groups: before treatment (T0), at completion of treatment (T1) and 3 months after completion of treatment (T2). RESULTS Similar rates of persistent QFT-GIT reversion were observed in groups A (19.0%, 173/910), B (18.5%, 165/890) and C (20.7%, 169/818) (p 0.512). The dynamic changes of IFN-γ levels were not statistically significant among the three groups. In treated participants, individuals with higher baseline IFN-γ levels showed increased TB occurrence (1.0%, 9/896) compared to those with lower baseline levels (0.2%, 2/904) (p 0.037). A similar but statistically insignificant trend was also observed in untreated controls (1.8% (7/400) vs. 0.5% (2/418), p 0.100). When TB cases were matched with non-TB cases on baseline IFN-γ levels, no significant differences were found with respect to the dynamic changes in IFN-γ levels with time, regardless of whether they received treatment. CONCLUSIONS QFT-GIT reversion or decreased IFN-γ levels should not be used for monitoring host response to latent TB infection treatment.
Collapse
Affiliation(s)
- H Xin
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China
| | - X Cao
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China
| | - H Zhang
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China
| | - J Liu
- The Sixth People's Hospital of Zhengzhou, PR China
| | - S Pan
- The Centers for Disease Prevention and Control of Zhongmu County, Zhengzhou, PR China
| | - X Li
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China
| | - L Guan
- The Sixth People's Hospital of Zhengzhou, PR China
| | - F Shen
- The Sixth People's Hospital of Zhengzhou, PR China
| | - Z Liu
- The Centers for Disease Prevention and Control of Zhongmu County, Zhengzhou, PR China
| | - D Wang
- The Centers for Disease Prevention and Control of Zhongmu County, Zhengzhou, PR China
| | - X Guan
- The Sixth People's Hospital of Zhengzhou, PR China
| | - J Yan
- The Centers for Disease Prevention and Control of Zhongmu County, Zhengzhou, PR China
| | - H Li
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China
| | - B Feng
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China
| | - M Zhang
- Guangdong Key Laboratory for Diagnosis &Treatment of Emerging Infectious Diseases, Shenzhen Third People's Hospital, Shenzhen University School of Medicine, Shenzhen, PR China
| | - Q Yang
- Guangdong Key Laboratory for Diagnosis &Treatment of Emerging Infectious Diseases, Shenzhen Third People's Hospital, Shenzhen University School of Medicine, Shenzhen, PR China
| | - Q Jin
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China
| | - L Gao
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for Tuberculosis Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China.
| | | |
Collapse
|
47
|
Li J, Yuan H, Li Y, Zhao XQ, Chen L, Han MK, Liu CQ, Liu Q, Wang HT, Zhong Q, Feng B. [Spectrum analysis of pathological classification in 463 cases with nasal and paranasal sinuses malignant tumors]. Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2020; 33:1176-1180. [PMID: 31914269 DOI: 10.13201/j.issn.1001-1781.2019.12.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Indexed: 11/12/2022]
Abstract
Objective:The characteristics of pathological histological classification of nasal and paranasal sinuses malignant tumors in the past 10 years were analyzed, so as to provide possible basis, direction and ideas for the development of relevant effective treatment measures for nasal and paranasal sinuses malignant tumors in clinical practice. Method:The clinical data of patients with nasal and paranasal sinuses malignant tumors admitted to PLA general hospital from January 2009 to December 2018 were collected. Pathological types were retrospectively analyzed, and disease spectrum distribution, composition ratio and variation tendency of these patients were calculated. Result:Among the 463 patients, the overall pathological types in the top 5 were as follows: squamous cell carcinoma, adenoid cystadenocarcinoma, olfactory neuroblastoma, melanoma, adenocarcinoma. As for male patients, the pathological types in the top 5 were squamous cell carcinoma, adenoid cystic carcinoma, olfactory neuroblastoma, adenocarcinoma, neuroendocrine carcinoma and rhabdomyosarcoma were tied for fifth; the top 5 most common pathological types in female patients were squamous cell carcinoma, adenoid cystic carcinoma, melanoma, rhabdomyosarcoma, and adenocarcinoma. From 2009 to 2013, there were 183 patients with nasal and paranasal sinuses malignant tumors, the top 5 pathological types were squamous cell carcinoma, adenoid cystadenocarcinoma, olfactory neuroblastoma, melanoma, neuroendocrine carcinoma and rhabdomyosarcoma were tied for fifth; From 2014 to 2018, 280 patients with nasal and paranasal sinuses malignant tumors were diagnosed, the top 5 pathological types were squamous cell carcinoma, adenoid cystadenocarcinoma, melanoma, adenocarcinoma, and rhabdomyosarcoma. The ratio of the number of patients from 2009 to 2013 and 2014 to 2018 was about 0.65∶1. Malignant tumors of the nasal and paranasal sinuses tend to occur between the ages of 41 and 60, and the pathological types in the top 5 were squamous cell carcinoma,adenoid cystic carcinoma, adenocarcinoma, melanoma, neuroendocrine carcinoma. Conclusion:Malignant tumors of nasal cavity and sinus were more common in male, and the pathological types such as squamous cell carcinoma, adenoid cystic carcinoma, olfactory neuroblastoma were more common. All age groups have the disease, but the age group of 41-60 years old is the high-risk group of nasal and nasal sinus malignant tumors. However, the incidence rate of melanoma has gradually increased in the past five years, which needs to be paid more attention to.
Collapse
Affiliation(s)
- J Li
- Department of Otorhinolaryngology Head and Neck Surgery,Hospital 301,PLA General Hospital,Beijing,100853,China.,Department of Otorhinolaryngology Head and Neck Surgery,the Second Affiliated Hospital of North Sichuan Medical College,Sichuan Mianyang 404 Hospital
| | - H Yuan
- Department of Otorhinolaryngology Head and Neck Surgery,Hospital 301,PLA General Hospital,Beijing,100853,China
| | - Y Li
- Department of Otorhinolaryngology Head and Neck Surgery,the Second Affiliated Hospital of North Sichuan Medical College,Sichuan Mianyang 404 Hospital
| | - X Q Zhao
- Department of Otorhinolaryngology Head and Neck Surgery,the Second Affiliated Hospital of North Sichuan Medical College,Sichuan Mianyang 404 Hospital
| | - L Chen
- Department of Otorhinolaryngology Head and Neck Surgery,Hospital 301,PLA General Hospital,Beijing,100853,China
| | - M K Han
- Department of Otorhinolaryngology Head and Neck Surgery,Hospital 301,PLA General Hospital,Beijing,100853,China
| | - C Q Liu
- Department of Otorhinolaryngology Head and Neck Surgery,Hospital 301,PLA General Hospital,Beijing,100853,China
| | - Q Liu
- Department of Otorhinolaryngology Head and Neck Surgery,Hospital 301,PLA General Hospital,Beijing,100853,China
| | - H T Wang
- Department of Otorhinolaryngology Head and Neck Surgery,Hospital 301,PLA General Hospital,Beijing,100853,China
| | - Q Zhong
- Department of Otorhinolaryngology Head and Neck Surgery,the Second Affiliated Hospital of North Sichuan Medical College,Sichuan Mianyang 404 Hospital
| | - B Feng
- Department of Otorhinolaryngology Head and Neck Surgery,Hospital 301,PLA General Hospital,Beijing,100853,China
| |
Collapse
|
48
|
Chen C, Kong L, Wang Y, Cheng P, Feng B, Zheng Q, Zhao J, Chen L, Wu K. Dynamics of Single-Molecule Dissociation by Selective Excitation of Molecular Phonons. Phys Rev Lett 2019; 123:246804. [PMID: 31922847 DOI: 10.1103/physrevlett.123.246804] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 09/18/2019] [Indexed: 06/10/2023]
Abstract
Breaking bonds selectively in molecules is vital in many chemistry reactions and custom nanoscale device fabrications. The scanning tunneling microscope (STM) has proved to be an ideal tool to initiate and view bond-selective chemistry at the single-molecule level, offering opportunities for the further study of the dynamics in single molecules on metal surfaces. We demonstrate H─HS and H─S bond breaking on Au(111) induced by tunneling electrons using low-temperature STM. An experimental study combined with theoretical calculations shows that the dissociation pathway is facilitated by vibrational excitations. Furthermore, the dissociation probabilities of the two different dissociation processes are bias dependent due to different inelastic-tunneling probabilities, and they are also closely linked to the lifetime of inelastic-tunneling electrons. Combined with time-dependent ab initio nonadiabatic molecular dynamics simulations, the dynamics of the injected electron and the phonon-excitation-induced molecule dissociation can be understood at the atomic scale, demonstrating the potential application of STM for the investigation of excited-state dynamics of single molecules on surfaces.
Collapse
Affiliation(s)
- Caiyun Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Longjuan Kong
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng Cheng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baojie Feng
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Qijing Zheng
- ICQD/Hefei National Laboratory for Physical Sciences at Microscale, and CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jin Zhao
- ICQD/Hefei National Laboratory for Physical Sciences at Microscale, and CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Lan Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Kehui Wu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physics, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| |
Collapse
|
49
|
Feng B, Qin CY, Geng XS, Yu Q, Wang WQ, Wu YT, Yan X, Ji LL, Shen BF. The emission of γ-Ray beams with orbital angular momentum in laser-driven micro-channel plasma target. Sci Rep 2019; 9:18780. [PMID: 31827174 PMCID: PMC6906474 DOI: 10.1038/s41598-019-55217-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/06/2019] [Indexed: 11/09/2022] Open
Abstract
We investigated the emission of multi-MeV γ-Ray beams with orbital angular momentum (OAM) from the interaction of an intense circularly polarized (CP) laser with a micro-channel plasma target. The driving laser can generate high energy electrons via direct laser acceleration within the channel. By attaching a plasma foil as the reflecting mirror, the CP laser is reflected and automatically colliding with the electrons. High energy gamma-photons are emitted through inverse Compton scattering (ICS) during collision. Three-dimensional particle-in-cell simulations reveal that the spin angular momentum (SAM) of the CP laser can be transferred to the OAM of accelerated electrons and further to the emitted gamma-ray beam. These results may guide future experiments in laser-driven gamma-ray sources using micro-structures.
Collapse
Affiliation(s)
- B Feng
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - C Y Qin
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - X S Geng
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Q Yu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China
| | - W Q Wang
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Y T Wu
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - X Yan
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - L L Ji
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China. .,Center for Excellence in Ultra-intense Laser Science, Chinese Academy of Sciences, Shanghai, 201800, China.
| | - B F Shen
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China. .,Shanghai Normal University, Shanghai, 200234, China.
| |
Collapse
|
50
|
Zhao Y, Feng B, Lee J, Lu N, Pierce DM. A multi-layered computational model for wrinkling of human skin predicts aging effects. J Mech Behav Biomed Mater 2019; 103:103552. [PMID: 32090947 DOI: 10.1016/j.jmbbm.2019.103552] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/16/2019] [Accepted: 11/21/2019] [Indexed: 01/31/2023]
Abstract
The development and progression of wrinkles from young to aged human skin relates to both structural and mechanical changes induced by aging. Here we aim to better understand the interaction of skin's layered morphology with dynamic wrinkles predicted in young and aged skin. First, we compare the predictions of wrinkling from 3-D finite element models of human skin including two to six distinct and anatomically motivated layers. Second, we perform parametric analyses using our six-layered model to determine how age-related changes in the architecture of human skin affect dynamic surface wrinkling. Specifically, we consider the following aging-related changes in the morphology of skin: flattening of the dermal-epidermal junction (DEJ) interface; thinning of both the viable epidermis (VE) and the reticular dermis (RD); and thickening of the papillary dermis (PD). We use skin compression to model dynamic, expressional wrinkles due to muscle contraction, and volumetric tissue loss to model effects of aging in wrinkling simulations. Our results highlight the role of skin's multi-layered structure in the modeling of wrinkling formation. Our six-layered model, consisting of all of the mechanical layers, predicts deep wrinkles with better fidelity than models including fewer layers. From our parametric study, applying our six-layered model, we conclude that: (1) the relative thicknesses of the layers in the epidermis or dermis significantly influences surface wrinkling in skin; and, (2) flattening of the DEJ with aging enhances surface wrinkling. Thinning of VE increases the relative stiffness of the epidermis and thus enhances dynamic wrinkling, while thickening of PD or thinning of RD has the same effect by reducing the equivalent stiffness of the substrate. Consequently, strategies to minimize wrinkling could maintain the undulating morphology of the DEJ, thereby delaying dynamic wrinkling and delaying the propagation of buckling into the deeper dermis or hypodermis. Additional strategies to minimize wrinkling could target preventing the VE and RD from thinning or preventing the PD from thickening.
Collapse
Affiliation(s)
- Y Zhao
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA
| | - B Feng
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - J Lee
- Unilever Research and Development, Trumbull, CT, USA
| | - N Lu
- Unilever Research and Development, Trumbull, CT, USA
| | - D M Pierce
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA; Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA.
| |
Collapse
|