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Lin AC, Pirrung F, Niestrawska JA, Ondruschka B, Pinter G, Henyš P, Hammer N. Shape or size matters? Towards standard reporting of tensile testing parameters for human soft tissues: systematic review and finite element analysis. Front Bioeng Biotechnol 2024; 12:1368383. [PMID: 38600944 PMCID: PMC11005100 DOI: 10.3389/fbioe.2024.1368383] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 03/14/2024] [Indexed: 04/12/2024] Open
Abstract
Material properties of soft-tissue samples are often derived through uniaxial tensile testing. For engineering materials, testing parameters (e.g., sample geometries and clamping conditions) are described by international standards; for biological tissues, such standards do not exist. To investigate what testing parameters have been reported for tensile testing of human soft-tissue samples, a systematic review of the literature was performed using PRISMA guidelines. Soft tissues are described as anisotropic and/or hyperelastic. Thus, we explored how the retrieved parameters compared against standards for engineering materials of similar characteristics. All research articles published in English, with an Abstract, and before 1 January 2023 were retrieved from databases of PubMed, Web of Science, and BASE. After screening of articles based on search terms and exclusion criteria, a total 1,096 articles were assessed for eligibility, from which 361 studies were retrieved and included in this review. We found that a non-tapered shape is most common (209 of 361), followed by a tapered sample shape (92 of 361). However, clamping conditions varied and were underreported (156 of 361). As a preliminary attempt to explore how the retrieved parameters might influence the stress distribution under tensile loading, a pilot study was performed using finite element analysis (FEA) and constitutive modeling for a clamped sample of little or no fiber dispersion. The preliminary FE simulation results might suggest the hypothesis that different sample geometries could have a profound influence on the stress-distribution under tensile loading. However, no conclusions can be drawn from these simulations, and future studies should involve exploring different sample geometries under different computational models and sample parameters (such as fiber dispersion and clamping effects). Taken together, reporting and choice of testing parameters remain as challenges, and as such, recommendations towards standard reporting of uniaxial tensile testing parameters for human soft tissues are proposed.
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Affiliation(s)
- Alvin C. Lin
- Division of Macroscopic and Clinical Anatomy, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
- Institute of Anatomy and Cell Biology, Paracelsus Medical University, Salzburg, Austria
| | - Felix Pirrung
- Division of Macroscopic and Clinical Anatomy, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Justyna A. Niestrawska
- Division of Macroscopic and Clinical Anatomy, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Benjamin Ondruschka
- Institute of Legal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Gerald Pinter
- Institute of Materials Science and Testing of Polymers, Montanuniversität Leoben, Leoben, Austria
| | - Petr Henyš
- Institute of New Technologies and Applied Informatics, Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Liberec, Czechia
| | - Niels Hammer
- Division of Macroscopic and Clinical Anatomy, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
- Department of Orthopedic and Trauma Surgery, University of Leipzig, Leipzig, Germany
- Fraunhofer Institute for Forming Tools, Division of Biomechatronics, Dresden, Germany
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Zhang M, Hao M, Tang X, Fan Y, Xia H. Synthetic Principles of Spiky Au Nanoparticles. ACS Appl Mater Interfaces 2023; 15:59722-59730. [PMID: 38091471 DOI: 10.1021/acsami.3c15615] [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: 12/28/2023]
Abstract
In this work, the synthetic principles of spiky Au nanoparticles (spiky Au NPs) with an average number of spikes of less than or equal to six and controlled core sizes by using Au nanorods as seeds (Au-NR seeds) are summarized on the basis of the results of a series of control experiments. In addition, one empirical equation that can roughly estimate the number of spiky Au NPs is proposed, demonstrated by the results of the products prepared from different aspect ratios of Au-NRs as seeds and non-Au-NR seeds. Moreover, the synthetic principles of spiky Au NPs are further demonstrated by taking the successful synthesis of a serials of spiky Au21×7 NPs. Furthermore, the as-prepared spiky Au@Au11.8Pd88.2 NPs with ultrathin AuPd shells, which are derived from spiky Au21×7 NPs with the smallest cores, can bear excellent catalytic activity (say, E1/2 = 0.947 V) and durability toward the oxygen reduction reaction (ORR) in alkaline conditions, compared with commercial Pt/C catalysts (E1/2 = 0.883 V).
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Affiliation(s)
- Mengmeng Zhang
- State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Mengjiao Hao
- State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Xueling Tang
- State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Yongchan Fan
- State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Haibing Xia
- State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
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Li G, Gao Y, Liu H, Xu H, Xiong W, Guo L, Li H, Chen G. Synergistic Improvement of Dielectric and Thermal Conductivity Properties for Polymers Filled with Multifunctional Modified Nanowires. ACS Appl Mater Interfaces 2023; 15:58828-58838. [PMID: 38051817 DOI: 10.1021/acsami.3c13359] [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: 12/07/2023]
Abstract
Dielectric composites are widely used in power electronics, power systems, aerospace, and other fields due to their extremely high power density. However, if their energy density can be further increased, the application range will be greatly improved. Improving the dielectric constant of composites is one of the most effective ways to increase the energy density. In this study, a preparation method for copper calcium titanate nanowires (CCTO-NWs) with adjustable aspect ratio was investigated. Upon incorporation of these CCTO-NWs into the polymer matrix, the nanocomposites exhibit a significantly higher dielectric constant and a lower dielectric loss. In addition, a thin layer of Al2O3 with excellent thermal conductivity is coated on the surface of the CCTO-NWs to form a core-shell structure nanowire CCTO-NW@Al2O3. The introduction of the thermal conductive layer of Al2O3 not only creates a continuous heat transfer path within the dielectric composite, increasing the thermal conductivity of the composite from 0.11 W/(m·K) of pure HIPS to 1.12 W/(m·K), but also serves as a buffer layer between HIPS and CCTO-NWs, effectively alleviating the electric field distortion caused by the large difference in the dielectric constant between them, thereby optimizing the dielectric properties of the composite and reducing the dielectric permeability threshold from 30 to 20 vol %. This work provides an effective strategy for synergistically improving the dielectric constant and thermal conductivity of dielectric composites while also taking into account the good flexibility of polymer/ceramic nanocomposites.
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Affiliation(s)
- Guan Li
- School of Energy and Materials, Shanghai Key Laboratory of Engineering Materials Application and Evaluation, Shanghai Polytechnic University, Shanghai 201209, China
| | - Ying Gao
- School of Energy and Materials, Shanghai Key Laboratory of Engineering Materials Application and Evaluation, Shanghai Polytechnic University, Shanghai 201209, China
| | - Huijing Liu
- School of Energy and Materials, Shanghai Key Laboratory of Engineering Materials Application and Evaluation, Shanghai Polytechnic University, Shanghai 201209, China
| | - Haiping Xu
- School of Energy and Materials, Shanghai Key Laboratory of Engineering Materials Application and Evaluation, Shanghai Polytechnic University, Shanghai 201209, China
- Shanghai Engineering Research Center of Advanced Thermal Functional Materials, Shanghai Thermophysical Properties Big Data Professional Technical Service Platform, Shanghai 201209, China
| | - Wei Xiong
- Shanghai Re-poly Environmental Protection Technology Co., Ltd., Shanghai 201209, China
| | - Lihe Guo
- School of Energy and Materials, Shanghai Key Laboratory of Engineering Materials Application and Evaluation, Shanghai Polytechnic University, Shanghai 201209, China
| | - Hongfei Li
- School of Energy and Materials, Shanghai Key Laboratory of Engineering Materials Application and Evaluation, Shanghai Polytechnic University, Shanghai 201209, China
| | - George Chen
- Department of Electronics and Computer Science, University of Southampton, Southampton SO171BJ, United Kingdom
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Kim HM, Cha BC, Kim DW. High-Rate One-Dimensional α-MnO 2 Anode for Lithium-Ion Batteries: Impact of Polymorphic and Crystallographic Features on Lithium Storage. Nanomaterials (Basel) 2023; 13:2808. [PMID: 37887958 PMCID: PMC10609827 DOI: 10.3390/nano13202808] [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: 10/09/2023] [Revised: 10/20/2023] [Accepted: 10/21/2023] [Indexed: 10/28/2023]
Abstract
Manganese dioxide (MnO2) exists in a variety of polymorphs and crystallographic structures. The electrochemical performance of Li storage can vary depending on the polymorph and the morphology. In this study, we present a new approach to fabricate polymorph- and aspect-ratio-controlled α-MnO2 nanorods. First, δ-MnO2 nanoparticles were synthesized using a solution plasma process assisted by three types of sugars (sucrose, glucose, and fructose) as reducing promoters; this revealed different morphologies depending on the nucleation rate and reaction time from the molecular structure of the sugars. Based on the morphology of δ-MnO2, the polymorphic-transformed three types of α-MnO2 nanorods showed different aspect ratios (c/a), which highly affected the transport of Li ions. Among them, a relatively small aspect ratio (c/a = 5.1) and wide width of α-MnO2-S nanorods (sucrose-assisted) induced facile Li-ion transport in the interior of the particles through an increased Li-ion pathway. Consequently, α-MnO2-S exhibited superior battery performance with a high-rate capability of 673 mAh g-1 at 2 A g-1, and it delivered a high reversible capacity of 1169 mAh g-1 at 0.5 A g-1 after 200 cycles. Our findings demonstrated that polymorphs and crystallographic properties are crucial factors in the electrode design of high-performance Li-ion batteries.
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Affiliation(s)
- Hye-min Kim
- Department of Materials Chemistry, Shinshu University, 4-17-1, Wakasato, Nagano 3808553, Japan;
| | - Byung-chul Cha
- Advanced Manufacturing Process R&D Group, Ulsan Division, Korea Institute of Industrial Technology (KITECH), 55, Jongga-ro, Jung-gu, Ulsan 44313, Republic of Korea
| | - Dae-wook Kim
- Advanced Manufacturing Process R&D Group, Ulsan Division, Korea Institute of Industrial Technology (KITECH), 55, Jongga-ro, Jung-gu, Ulsan 44313, Republic of Korea
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Radhakrishnan G, Breaz D, Al Hattali AHMS, Al Yahyai AMN, Al Riyami AMNO, Al Hadhrami AMD, Karthikeyan KR. Influence of Aspect Ratio on the Flexural and Buckling Behavior of an Aluminium Sandwich Composite: A Numerical and Experimental Approach. Materials (Basel) 2023; 16:6544. [PMID: 37834680 PMCID: PMC10573770 DOI: 10.3390/ma16196544] [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: 09/07/2023] [Revised: 09/24/2023] [Accepted: 10/02/2023] [Indexed: 10/15/2023]
Abstract
In the field of engineering materials, lightweight and ultra-lightweight composites are used in real time to a greater extent, with high-performance targeting for tailor-made systems in aerospace, automotive, and biomedical applications. Sandwich composites are among the most popular lightweight materials used in structural and vehicle-building applications. In the present investigation, one such sandwich composite laminate composed of aluminum face sheets and a high-density polyethylene core was considered to analyze sandwich composites' flexural and buckling behavior experimentally and numerically. The influence of aspect ratios, such as length to thickness and width to thickness, on the flexural and buckling performance of sandwich composite laminates was explored in the study. Laminates with different widths, namely, 10, 12, and 15 mm, and a uniform thickness and length of 3 mm and 150 mm, respectively, were used for flexural analysis, whereas laminates with widths of 10, 12, and 15 mm and a uniform thickness and length of 3 mm and 350 mm, respectively, were used for buckling analysis. The geometrical influence of the laminates on mechanical performance was studied through performance measures such as critical bending load, flexural stiffness, inter-laminar shear stress, and critical buckling load. A significant influence of aspect ratio on the mechanical behavior of the laminates was observed using both experimental and numerical approaches. Flexural behavior was observed to be better at greater widths, namely, 15 mm, and with a minimum support span of 90 mm due to reduced spring back effects and increased bending resistance. A maximum width of 15 mm allowed for a higher buckling load capacity similar to that of bending resistance. A critical buckling load of 655.8 N seemed to be the maximum and was obtained for the highest aspect ratio, b/t = 5. The soft core and ductile metal face sheets offered combined resistance to both bending and buckling. A lower aspect ratio (span to thickness) rendered these sandwich laminates better in terms of both bending and buckling.
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Affiliation(s)
- Ganesh Radhakrishnan
- Department of Mechanical Engineering, College of Engineering & Technology, University of Technology & Applied Sciences, Nizwa P.O. Box 477, Oman; (G.R.); (A.H.M.S.A.H.); (A.M.N.A.Y.); (A.M.N.O.A.R.); (A.M.D.A.H.)
| | - Daniel Breaz
- Department of Mathematics, “1 Decembrie 1918” University of Alba Iulia, 510009 Alba Iulia, Romania
| | - Al Haitham Mohammed Sulaiman Al Hattali
- Department of Mechanical Engineering, College of Engineering & Technology, University of Technology & Applied Sciences, Nizwa P.O. Box 477, Oman; (G.R.); (A.H.M.S.A.H.); (A.M.N.A.Y.); (A.M.N.O.A.R.); (A.M.D.A.H.)
| | - Al Muntaser Nasser Al Yahyai
- Department of Mechanical Engineering, College of Engineering & Technology, University of Technology & Applied Sciences, Nizwa P.O. Box 477, Oman; (G.R.); (A.H.M.S.A.H.); (A.M.N.A.Y.); (A.M.N.O.A.R.); (A.M.D.A.H.)
| | - Al Muntaser Nasser Omar Al Riyami
- Department of Mechanical Engineering, College of Engineering & Technology, University of Technology & Applied Sciences, Nizwa P.O. Box 477, Oman; (G.R.); (A.H.M.S.A.H.); (A.M.N.A.Y.); (A.M.N.O.A.R.); (A.M.D.A.H.)
| | - Al Muatasim Dawood Al Hadhrami
- Department of Mechanical Engineering, College of Engineering & Technology, University of Technology & Applied Sciences, Nizwa P.O. Box 477, Oman; (G.R.); (A.H.M.S.A.H.); (A.M.N.A.Y.); (A.M.N.O.A.R.); (A.M.D.A.H.)
| | - Kadhavoor R. Karthikeyan
- Department of Applied Mathematics and Science, National University of Science & Technology, Muscat P.O. Box 620, Oman
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Lu C, Zheng J, Yoshitomi T, Kawazoe N, Yang Y, Chen G. How Hydrogel Stiffness Affects Adipogenic Differentiation of Mesenchymal Stem Cells under Controlled Morphology. ACS Appl Bio Mater 2023; 6:3441-3450. [PMID: 37061939 DOI: 10.1021/acsabm.3c00159] [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] [Indexed: 04/17/2023]
Abstract
Matrix stiffness has been disclosed as an essential regulator of cell fate. However, it is barely studied how the matrix stiffness affects stem cell functions when cell morphology changes. Thus, in this study, the effect of hydrogel stiffness on adipogenic differentiation of human bone-marrow-derived mesenchymal stem cells (hMSCs) with controlled morphology was investigated. Micropatterns of different size and elongation were prepared by a photolithographical micropatterning technique. The hMSCs were cultured on the micropatterns and showed a different spreading area and elongation following the geometry of the underlying micropatterns. The cells with controlled morphology were embedded in agarose hydrogels of different stiffnesses. The cells showed a different level of adipogenic differentiation that was dependent on both hydrogel stiffness and cell morphology. Adipogenic differentiation became strong when the cell spreading area decreased and hydrogel stiffness increased. Adipogenic differentiation did not change with cell elongation. Therefore, cell spreading area and hydrogel stiffness could synergistically affect adipogenic differentiation of hMSCs, while cell elongation did not affect adipogenic differentiation. A change of cell morphology and hydrogel stiffness was accompanied by actin filament alignment that was strongly related to adipogenic differentiation. The results indicated that cell morphology could affect cellular sensitivity to hydrogel stiffness. The results will provide useful information for the elucidation of the interaction of stem cells and their microenvironmental biomechanical cues.
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Affiliation(s)
- Chengyu Lu
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
- Department of Materials Science and Engineering, Graduate School of Pure and Applied Science, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
| | - Jing Zheng
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Toru Yoshitomi
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Naoki Kawazoe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Yingnan Yang
- Graduate School of Life and Environment Science, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Guoping Chen
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
- Department of Materials Science and Engineering, Graduate School of Pure and Applied Science, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
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7
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Zhang C, Liu D. [Characterization of bacterial swarming motility: a review]. Sheng Wu Gong Cheng Xue Bao 2023; 39:3188-3203. [PMID: 37622355 DOI: 10.13345/j.cjb.220892] [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: 08/26/2023]
Abstract
Swarming motility is a typical synergistic motion, in which bacteria use flagella and Type Ⅳ Pili together to move collectively on semi-solid surfaces. Swarming motility is a hot topic of research in the field of microbiology because of its close relationship with biofilm formation, fruiting bodies formation, pathogen invasion and microbial dispersal and symbiosis. A large number of studies have been conducted on bacterial swarming motility, including changes in the expression of key proteins, changes in chemical communications between bacteria as well as mechanical changes. The expression of flagellin and the level of intracellular c-di-GMP complicatedly regulates the collective behavior of bacteria in colonies, which consequently impacts the swarming motility. The unique physical properties of swarmer cells are conducive to the expansion of the whole colony. Factors such as nutrient and water content in the surrounding growth environment of bacteria also affect the ability of bacteria to swarm to different degrees. It is challenging to construct a universal model of swarming motility based on the molecular mechanisms of swarming in the future.
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Affiliation(s)
- Chenxi Zhang
- Key Laboratory of Systems Bioengineering of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
| | - Dingkuo Liu
- Tianjin Key Laboratory of Biological Feed Additives, Tianjin 300383, China
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8
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Han P, Zhuang X, Zuo H, Lou P, Chen X. The Lightweight Anchor Dynamic Assignment Algorithm for Object Detection. Sensors (Basel) 2023; 23:6306. [PMID: 37514601 PMCID: PMC10384063 DOI: 10.3390/s23146306] [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: 06/07/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023]
Abstract
Smart security based on object detection is one of the important applications of edge computing in IoT. Anchors in object detection refer to points on the feature map, which can be used to generate anchor boxes and serve as training samples. Current object detection models do not consider the aspect ratio of the ground-truth boxes in anchor assignment and are not well-adapted to objects with very different shapes. Therefore, this paper proposes the Lightweight Anchor Dynamic Assignment algorithm (LADA) for object detection. LADA does not change the structure of the original detection model; first, it selects an equal proportional center region based on the aspect ratio of the ground-truth box, then calculates the combined loss of anchors, and finally divides the positive and negative samples more efficiently by dynamic loss threshold without additional models. The algorithm solves the problems of poor adaptability and difficulty in the selection of the best positive samples based on IoU assignment, and the sample assignment for eccentric objects and objects with different aspect ratios was more reasonable. Compared with existing sample assignment algorithms, the LADA algorithm outperforms the MS COCO dataset by 1.66% over the AP of the baseline FCOS, and 0.76% and 0.24% over the AP of the ATSS algorithm and the PAA algorithm, respectively, with the same model structure, which demonstrates the effectiveness of the LADA algorithm.
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Affiliation(s)
- Ping Han
- School of Information Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Xujun Zhuang
- School of Information Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Huahong Zuo
- Wuhan Chuyan Information Technology Co., Ltd., Wuhan 430030, China
| | - Ping Lou
- School of Information Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Xiao Chen
- School of Information Engineering, Wuhan University of Technology, Wuhan 430070, China
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9
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Min Y, Zhao G, Pan D, Shao X. Aspect Ratio Effects on the Aerodynamic Performance of a Biomimetic Hummingbird Wing in Flapping. Biomimetics (Basel) 2023; 8:216. [PMID: 37366811 DOI: 10.3390/biomimetics8020216] [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] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/07/2023] [Accepted: 05/22/2023] [Indexed: 06/28/2023] Open
Abstract
Hummingbirds are flapping winged creatures with unique flight mechanisms. Their flight pattern is more similar to insects than other birds. Because their flight pattern provides a large lift force at a very small scale, hummingbirds can remain hovering while flapping. This feature is of high research value. In order to understand the high-lift mechanism of hummingbirds' wings, in this study a kinematic model is established based on hummingbirds' hovering and flapping process, and wing models imitating the wing of a hummingbird are designed with different aspect ratios. Therefore, with the help of computational fluid dynamics methods, the effect of aspect ratio changes on the aerodynamic characteristics of hummingbirds' hovering and flapping are explored in this study. Through two different quantitative analysis methods, the results of lift coefficient and drag coefficient show completely opposite trends. Therefore, lift-drag ratio is introduced to better evaluate aerodynamic characteristics under different aspect ratios, and it is found that the lift-drag ratio reaches a higher value when AR = 4. A similar conclusion is also reached following research on the power factor, which shows that the biomimetic hummingbird wing with AR = 4 has better aerodynamic characteristics. Furthermore, the study of the pressure nephogram and vortices diagram in the flapping process are examined, leading to elucidation of the effect of aspect ratio on the flow field around hummingbirds' wings and how these effects ultimately lead to changes in the aerodynamic characteristics of the birds' wings.
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Affiliation(s)
- Yilong Min
- State Key Laboratory of Fluid Power and Mechatronic Systems, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China
| | - Gengyao Zhao
- State Key Laboratory of Fluid Power and Mechatronic Systems, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China
| | - Dingyi Pan
- State Key Laboratory of Fluid Power and Mechatronic Systems, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China
| | - Xueming Shao
- State Key Laboratory of Fluid Power and Mechatronic Systems, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China
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Haslinger MJ, Maier OS, Pribyl M, Taus P, Kopp S, Wanzenboeck HD, Hingerl K, Muehlberger MM, Guillén E. Increasing the Stability of Isolated and Dense High-Aspect-Ratio Nanopillars Fabricated Using UV-Nanoimprint Lithography. Nanomaterials (Basel) 2023; 13:nano13091556. [PMID: 37177101 PMCID: PMC10180511 DOI: 10.3390/nano13091556] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 04/28/2023] [Accepted: 04/29/2023] [Indexed: 05/15/2023]
Abstract
Structural anti-reflective coating and bactericidal surfaces, as well as many other effects, rely on high-aspect-ratio (HAR) micro- and nanostructures, and thus, are of great interest for a wide range of applications. To date, there is no widespread fabrication of dense or isolated HAR nanopillars based on UV nanoimprint lithography (UV-NIL). In addition, little research on fabricating isolated HAR nanopillars via UV-NIL exists. In this work, we investigated the mastering and replication of HAR nanopillars with the smallest possible diameters for dense and isolated arrangements. For this purpose, a UV-based nanoimprint lithography process was developed. Stability investigations with capillary forces were performed and compared with simulations. Finally, strategies were developed in order to increase the stability of imprinted nanopillars or to convert them into nanoelectrodes. We present UV-NIL replication of pillars with aspect ratios reaching up to 15 with tip diameters down to 35 nm for the first time. We show that the stability could be increased by a factor of 58 when coating them with a 20 nm gold layer and by a factor of 164 when adding an additional 20 nm thick layer of SiN. The coating of the imprints significantly improved the stability of the nanopillars, thus making them interesting for a wide range of applications.
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Affiliation(s)
| | - Oliver S Maier
- PROFACTOR GmbH, 4407 Steyr-Gleink, Austria
- Center for Surface and Nanoanalytics, Johannes Kepler University Linz, 4040 Linz, Austria
| | - Markus Pribyl
- TU Wien, Institute for Solid State Electronics, 1040 Vienna, Austria
| | - Philipp Taus
- TU Wien, Institute for Solid State Electronics, 1040 Vienna, Austria
| | - Sonja Kopp
- PROFACTOR GmbH, 4407 Steyr-Gleink, Austria
| | | | - Kurt Hingerl
- Center for Surface and Nanoanalytics, Johannes Kepler University Linz, 4040 Linz, Austria
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Benselfelt T, Kummer N, Nordenström M, Fall AB, Nyström G, Wågberg L. The Colloidal Properties of Nanocellulose. ChemSusChem 2023; 16:e202201955. [PMID: 36650954 DOI: 10.1002/cssc.202201955] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 01/16/2023] [Indexed: 06/17/2023]
Abstract
Nanocelluloses are anisotropic nanoparticles of semicrystalline assemblies of glucan polymers. They have great potential as renewable building blocks in the materials platform of a more sustainable society. As a result, the research on nanocellulose has grown exponentially over the last decades. To fully utilize the properties of nanocelluloses, a fundamental understanding of their colloidal behavior is necessary. As elongated particles with dimensions in a critical nanosize range, their colloidal properties are complex, with several behaviors not covered by classical theories. In this comprehensive Review, we describe the most prominent colloidal behaviors of nanocellulose by combining experimental data and theoretical descriptions. We discuss the preparation and characterization of nanocellulose dispersions, how they form networks at low concentrations, how classical theories cannot describe their behavior, and how they interact with other colloids. We then show examples of how scientists can use this fundamental knowledge to control the assembly of nanocellulose into new materials with exceptional properties. We hope aspiring and established researchers will use this Review as a guide.
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Affiliation(s)
- Tobias Benselfelt
- Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden
- Wallenberg Wood Science Center, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore, Singapore
| | - Nico Kummer
- Laboratory for Cellulose & Wood Materials, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland
- Department of Health Sciences and Technology, ETH Zürich, 8092, Zürich, Switzerland
| | - Malin Nordenström
- Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden
- Wallenberg Wood Science Center, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden
| | | | - Gustav Nyström
- Laboratory for Cellulose & Wood Materials, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland
- Department of Health Sciences and Technology, ETH Zürich, 8092, Zürich, Switzerland
| | - Lars Wågberg
- Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden
- Wallenberg Wood Science Center, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden
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12
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Yargholi E, Op de Beeck H. Category Trumps Shape as an Organizational Principle of Object Space in the Human Occipitotemporal Cortex. J Neurosci 2023; 43:2960-2972. [PMID: 36922027 PMCID: PMC10124953 DOI: 10.1523/jneurosci.2179-22.2023] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 02/22/2023] [Accepted: 03/03/2023] [Indexed: 03/17/2023] Open
Abstract
The organizational principles of the object space represented in the human ventral visual cortex are debated. Here we contrast two prominent proposals that, in addition to an organization in terms of animacy, propose either a representation related to aspect ratio (stubby-spiky) or to the distinction between faces and bodies. We designed a critical test that dissociates the latter two categories from aspect ratio and investigated responses from human fMRI (of either sex) and deep neural networks (BigBiGAN). Representational similarity and decoding analyses showed that the object space in the occipitotemporal cortex and BigBiGAN was partially explained by animacy but not by aspect ratio. Data-driven approaches showed clusters for face and body stimuli and animate-inanimate separation in the representational space of occipitotemporal cortex and BigBiGAN, but no arrangement related to aspect ratio. In sum, the findings go in favor of a model in terms of an animacy representation combined with strong selectivity for faces and bodies.SIGNIFICANCE STATEMENT We contrasted animacy, aspect ratio, and face-body as principal dimensions characterizing object space in the occipitotemporal cortex. This is difficult to test, as typically faces and bodies differ in aspect ratio (faces are mostly stubby and bodies are mostly spiky). To dissociate the face-body distinction from the difference in aspect ratio, we created a new stimulus set in which faces and bodies have a similar and very wide distribution of values along the shape dimension of the aspect ratio. Brain imaging (fMRI) with this new stimulus set showed that, in addition to animacy, the object space is mainly organized by the face-body distinction and selectivity for aspect ratio is minor (despite its wide distribution).
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Affiliation(s)
- Elahe' Yargholi
- Department of Brain and Cognition, Leuven Brain Institute, Faculty of Psychology & Educational Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Hans Op de Beeck
- Department of Brain and Cognition, Leuven Brain Institute, Faculty of Psychology & Educational Sciences, KU Leuven, 3000 Leuven, Belgium
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13
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Lv C, Wei H, Lan Z, Wu P. Nonlinear Modeling of Contact Stress Distribution in Thin Plate Substrates Subjected to Aspect Ratio. Sensors (Basel) 2023; 23:4050. [PMID: 37112396 PMCID: PMC10146796 DOI: 10.3390/s23084050] [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] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/09/2023] [Accepted: 04/12/2023] [Indexed: 06/19/2023]
Abstract
The foundation substrate's basal contact stresses are typically thought to have a linear distribution, although the actual form is nonlinear. Basal contact stress in thin plates is experimentally measured using a thin film pressure distribution system. This study examines the nonlinear distribution law of basal contact stresses in thin plates with various aspect ratios under concentrated loading, and it establishes a model for the distribution of contact stresses in thin plates using an exponential function that accounts for aspect ratio coefficients. The outcomes demonstrate that the thin plate's aspect ratio significantly affects how the substrate contact stress is distributed during concentrated loading. The contact stresses in the thin plate's base exhibit significant nonlinearity when the aspect ratio of the test thin plate is greater than 6~8. The aspect ratio coefficient-added exponential function model can better optimize the strength and stiffness calculations of the base substrate and more accurately describe the actual distribution of contact stresses in the base of the thin plate compared to linear and parabolic functions. The correctness of the exponential function model is confirmed by the film pressure distribution measurement system that directly measures the contact stress at the base of the thin plate, providing a more accurate nonlinear load input for the calculation of the internal force of the base thin plate.
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Affiliation(s)
| | | | | | - Ping Wu
- Correspondence: ; Tel.: +86-178-3516-0913
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14
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Kim HJ, Lee WJ. The Influence of Cellulose Nanocrystal Characteristics on Regenerative Silk Composite Fiber Properties. Materials (Basel) 2023; 16:2323. [PMID: 36984203 PMCID: PMC10052345 DOI: 10.3390/ma16062323] [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] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/11/2023] [Accepted: 03/13/2023] [Indexed: 06/18/2023]
Abstract
Cellulose nanocrystals (CNCs), obtained from natural resources, possess great potential as a bioderived reinforcement for natural-fiber-reinforced composites (NFRPs) due to their superior crystallinity and high aspect ratio. To elucidate the specific parameters of CNCs that significantly affect their mechanical performance, various CNCs were investigated to fabricate high-performance nanocomposite fibers together with regenerated silk fibroin (RSF). We confirmed that the high aspect ratio (~9) of the CNCs was the critical factor to increase the tensile strength and stiffness rather than the crystallinity. At a 1 vol% of CNCs, the strength and stiffness reached ~300 MPa and 10.5 GPa, respectively, which was attributed not only to a stable dispersion but also to alignment. This approach has the potential to evaluate the parameters of natural reinforcement and may also be useful in constructing high-performance NFRPs.
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15
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Bowman CS, Traband R, Wang X, Knowles SP, Lo S, Jia Z, Vorsa N, Herniter IA. Multiple Leaf Sample Extraction System (MuLES): A tool to improve automated morphometric leaf studies. Appl Plant Sci 2023; 11:e11513. [PMID: 37051583 PMCID: PMC10083438 DOI: 10.1002/aps3.11513] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 11/13/2022] [Accepted: 11/29/2022] [Indexed: 06/19/2023]
Abstract
PREMISE The measurement of leaf morphometric parameters from digital images can be time-consuming or restrictive when using digital image analysis softwares. The Multiple Leaf Sample Extraction System (MuLES) is a new tool that enables high-throughput leaf shape analysis with minimal user input or prerequisites, such as coding knowledge or image modification. METHODS AND RESULTS MuLES uses contrasting pixel color values to distinguish between leaf objects and their background area, eliminating the need for color threshold-based methods or color correction cards typically required in other software methods. The leaf morphometric parameters measured by this software, especially leaf aspect ratio, were able to distinguish between large populations of different accessions for the same species in a high-throughput manner. CONCLUSIONS MuLES provides a simple method for the rapid measurement of leaf morphometric parameters in large plant populations from digital images and demonstrates the ability of leaf aspect ratio to distinguish between closely related plant types.
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Affiliation(s)
- Christian S. Bowman
- Department of Botany and Plant SciencesUniversity of CaliforniaRiverside, 2142 Batchelor HallRiversideCalifornia92521USA
| | - Ryan Traband
- Department of Botany and Plant SciencesUniversity of CaliforniaRiverside, 2142 Batchelor HallRiversideCalifornia92521USA
| | - Xuesong Wang
- Department of Botany and Plant SciencesUniversity of CaliforniaRiverside, 2142 Batchelor HallRiversideCalifornia92521USA
| | - Sara P. Knowles
- Department of Plant BiologyRutgers University59 Dudley RoadNew BrunswickNew Jersey08901USA
| | - Sassoum Lo
- Department of Plant SciencesUniversity of California, Davis, One Shields AvenueDavisCalifornia95616USA
| | - Zhenyu Jia
- Department of Botany and Plant SciencesUniversity of CaliforniaRiverside, 2142 Batchelor HallRiversideCalifornia92521USA
| | - Nicholi Vorsa
- Department of Plant BiologyRutgers University59 Dudley RoadNew BrunswickNew Jersey08901USA
| | - Ira A. Herniter
- Department of Plant BiologyRutgers University59 Dudley RoadNew BrunswickNew Jersey08901USA
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16
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Ma K, Li S, Xu C, Gao Z, Yang L, Lu B. Study on the Process Characteristics Based on Joule Heat of Sliding-Pressure Additive Manufacturing. Materials (Basel) 2023; 16:2017. [PMID: 36903127 PMCID: PMC10003864 DOI: 10.3390/ma16052017] [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] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/20/2023] [Accepted: 02/24/2023] [Indexed: 06/18/2023]
Abstract
This study developed an experimental system based on Joule heat of sliding-pressure additive manufacturing (SP-JHAM), and Joule heat was used for the first time to accomplish high-quality single-layer printing. The roller wire substrate is short-circuited, and Joule heat is generated to melt the wire when the current passes through. Through the self-lapping experimental platform, single-factor experiments were designed to study the effects of power supply current, electrode pressure, contact length on the surface morphology and cross-section geometric characteristics of the single-pass printing layer. Through the Taguchi method, the effect of various factors was analyzed, the optimal process parameters were obtained, and the quality was detected. The results show that with the current increase, the aspect ratio and dilution rate of a printing layer increase within a given range of process parameters. In addition, with the increase in pressure and contact length, the aspect ratio and dilution ratio decrease. Pressure has the greatest effect on the aspect ratio and dilution ratio, followed by current and contact length. When a current of 260 A, a pressure of 0.60 N and a contact length of 1.3 mm are applied, a single track with a good appearance, whose surface roughness Ra is 3.896 μm, can be printed. Additionally, the wire and the substrate are completely metallurgically bonded with this condition. There are also no defects such as air holes and cracks. This study verified the feasibility of SP-JHAM as a new additive manufacturing strategy with high quality and low cost, and provided a reference for developing additive manufacturing technology based on Joule heat.
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Affiliation(s)
- Kaiyue Ma
- School of Mechanical Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
- National Innovation Institute of Additive Manufacturing, Xi’an 710300, China
- State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Suli Li
- School of Mechanical Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
- National Innovation Institute of Additive Manufacturing, Xi’an 710300, China
- State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Chao Xu
- School of Mechanical Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
| | - Zhuang Gao
- School of Mechanical Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
| | - Laixia Yang
- School of Mechanical Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
- State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Bingheng Lu
- National Innovation Institute of Additive Manufacturing, Xi’an 710300, China
- State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
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Afolabi OA, Mohan TP, Kanny K. Processing of Low-Density HGM-Filled Epoxy-Syntactic Foam Composites with High Specific Properties for Marine Applications. Materials (Basel) 2023; 16:ma16041732. [PMID: 36837359 PMCID: PMC9966764 DOI: 10.3390/ma16041732] [Citation(s) in RCA: 1] [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] [Received: 01/10/2023] [Revised: 02/17/2023] [Accepted: 02/17/2023] [Indexed: 06/01/2023]
Abstract
A solution casting approach is used to create hollow glass microsphere (HGM)-filled epoxy-syntactic foam composites (e-SFCs) by varying the concentrations of HGM in epoxy according to different particle sizes. Density analysis is used to investigate the impact of concentration and particle size regularity on the microstructure of e-SFCs. It was observed that e-SFCs filled with an HGM of uniform particle sizes exhibit a reduction in density with increasing HGM concentration, whereas e-SFCs filled with heterogeneous sizes of HGM exhibit closeness in density values regardless of HGM concentration. The variation in e-SFC density can be related to HGM packing efficiency within e-SFCs in terms of concentration and particle size regularity. The particle size with lowest true density of 0.5529 g/cm3, experimental density of 0.949 g/cm3 and tensile strength of 55.74 MPa resulted in e-SFCs with highest specific properties of 100.81 (MPa·g/cm3), with a 35.1% increase from the lowest value of 74.64 (MPa·g/cm3) at a true density of 0.7286 g/cm3, experimental density of 0.928 g/cm3 and tensile strength of 54.38 MPa. The e-SFCs' theoretical density values were obtained. The variance in theoretical and experimental density values provides a thorough grasp of packing efficiency and inter-particle features.
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18
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Rajaraman S, Yang F, Zamzmi G, Xue Z, Antani S. Assessing the Impact of Image Resolution on Deep Learning for TB Lesion Segmentation on Frontal Chest X-rays. Diagnostics (Basel) 2023; 13:diagnostics13040747. [PMID: 36832235 PMCID: PMC9955202 DOI: 10.3390/diagnostics13040747] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/10/2023] [Accepted: 02/15/2023] [Indexed: 02/18/2023] Open
Abstract
Deep learning (DL) models are state-of-the-art in segmenting anatomical and disease regions of interest (ROIs) in medical images. Particularly, a large number of DL-based techniques have been reported using chest X-rays (CXRs). However, these models are reportedly trained on reduced image resolutions for reasons related to the lack of computational resources. Literature is sparse in discussing the optimal image resolution to train these models for segmenting the tuberculosis (TB)-consistent lesions in CXRs. In this study, we investigated the performance variations with an Inception-V3 UNet model using various image resolutions with/without lung ROI cropping and aspect ratio adjustments and identified the optimal image resolution through extensive empirical evaluations to improve TB-consistent lesion segmentation performance. We used the Shenzhen CXR dataset for the study, which includes 326 normal patients and 336 TB patients. We proposed a combinatorial approach consisting of storing model snapshots, optimizing segmentation threshold and test-time augmentation (TTA), and averaging the snapshot predictions, to further improve performance with the optimal resolution. Our experimental results demonstrate that higher image resolutions are not always necessary; however, identifying the optimal image resolution is critical to achieving superior performance.
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19
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Zhang L, Harrison W, Mehraban S, Brown SGR, Lavery NP. Size Effect on the Post-Necking Behaviour of Dual-Phase 800 Steel: Modelling and Experiment. Materials (Basel) 2023; 16:1458. [PMID: 36837087 PMCID: PMC9964128 DOI: 10.3390/ma16041458] [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] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/30/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
This work investigated the feasibility of using a miniaturised non-standard tensile specimen to predict the post-necking behaviour of the materials manufactured via a rapid alloy prototyping (RAP) approach. The experimental work focused on the determination of the Lankford coefficients (r-value) of dual-phase 800 (DP800) steel and the digital image correlation (DIC) for some cases, which were used to help calibrate the damage model parameters of DP800 steel. The three-dimensional numerical simulations focused on the influence of the size effect (aspect ratio, AR) on the post-necking behaviour, such as the strain/stress/triaxiality evolutions, fracture angles, and necking mode transitions. The modelling showed that although a good correlation can be found between the predicted and experimentally observed ultimate tensile strength (UTS) and total elongation. The standard tensile specimen with a gauge length of 80 mm exhibited a fracture angle of ∼55°, whereas the smaller miniaturised non-standard specimens with low ARs exhibited fractures perpendicular to the loading direction. This shows that care must be taken when comparing the post-necking behaviour of small-scale tensile tests, such as those completed as a part of a RAP approach, to the post-necking behaviours of standard full-size test specimens. However, the modelling work showed that this behaviour is well represented, demonstrating a transition between the fracture angles of the samples between 2.5 and 5. This provides more confidence in understanding the post-necking behaviour of small-scale tensile tests.
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20
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Yang D, Wu XD, Zhou Y, Yin X, Huang Y, Shao H, Tang H. Correlation between tibial valgus deformity and aspect ratio of resected tibial surface in female Chinese patients undergoing total knee arthroplasty. Front Surg 2023; 9:1079981. [PMID: 36684171 PMCID: PMC9852758 DOI: 10.3389/fsurg.2022.1079981] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 12/07/2022] [Indexed: 01/09/2023] Open
Abstract
Background Morphology of the resected tibial surface is the reference for tibial component design, selection, and implantation in total knee arthroplasty (TKA). This comparative study sought to answer whether valgus deformity of the tibia would affect the morphology of the resected tibial surface in TKA. Methods Thirty-one female Chinese patients with valgus tibias were retrospectively and consecutively identified from a single-center registration database. Thirty-one patients with well-aligned tibias were matched in terms of gender, height, and weight. Weight-bearing full-length radiographs and computed tomography images of the whole lower limb were obtained for every case. Tibial resection was mimicked perpendicular to the mechanical axis of the tibia in the frontal plane with 3° of posterior slope and a cut level individualized by the actual intraoperative cut. On the resected surface, mediolateral dimension (MLD), medial anteroposterior dimensions (mAPD), and lateral anteroposterior dimensions (lAPD) were measured, and aspect ratios (AR) were calculated. We compared the AR between the two groups. Results The aspect ratio of resected tibial surface positively correlated with tibial valgus alignment. Patients with valgus tibias had significantly smaller AR (MLD/mAPD) for the medial plateau (1.50 ± 0.06 vs. 1.54 ± 0.07, P = 0.032). However, the AR for the lateral plateau was similar between the two groups (1.63 ± 0.08 vs. 1.65 ± 0.07, P = 0.328). Conclusion This difference in morphology of resected tibial surface between valgus and well-aligned tibias should be considered in tibial component design, as well as in the selection and placement of TKA implants for knees with valgus tibias.
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21
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Gardner M, Cross M, Reed S, Davidson M, Hughes R, Oosthuizen J. Pathogenic Potential of Respirable Spodumene Cleavage Fragments following Application of Regulatory Counting Criteria for Asbestiform Fibres. Int J Environ Res Public Health 2022; 19:16649. [PMID: 36554530 PMCID: PMC9779135 DOI: 10.3390/ijerph192416649] [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] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/05/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Health risks from exposure to lithium-bearing spodumene cleavage fragments are unknown. While asbestiform fibres can lead to fibrosis, mesothelioma and lung cancer, controversy remains whether non-asbestiform cleavage fragments, having equivalent dimensions, elicit similar pathologic responses. The mineralogy of respirable particles from two alpha (α)-spodumene concentrate grades (chemical and technical) were characterised using semi-quantitative X-ray diffraction (XRD). Particles were measured using scanning electron microscopy (SEM) and the dimensions (length [L], diameter [D], aspect ratio [AR]) applied to regulatory counting criteria for asbestiform fibres. Application of the current World Health Organization (WHO) and National Occupational Health and Safety Commission (NOHSC) counting criteria, L ˃ 5 µm, D ˂ 3 µm, AR ˃ 3:1, to 10 SEM images of each grade identified 47 countable particles in the chemical and 37 in the technical concentrate test samples. Of these particles, 17 and 16 in the chemical and technical test samples, respectively, satisfied the more rigorous, previously used Mines Safety and Inspection Regulations 1995 (Western Australia [WA]) criteria, L ˃ 5 µm and D ≤ 1 µm. The majority of the countable particles were consistent with α-spodumene cleavage fragments. These results suggest elongated α-spodumene particles may pose a health risk. It is recommended the precautionary principle be applied to respirable α-spodumene particles and the identification and control of dust hazards in spodumene extraction, handling and processing industries be implemented.
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Affiliation(s)
- Melinda Gardner
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
| | - Martyn Cross
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
| | - Sue Reed
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
| | - Maggie Davidson
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
- School of Science, Western Sydney University, Bourke Street, Richmond, NSW 2753, Australia
| | - Rick Hughes
- Microanalysis Australia, 5 Alvan Street, Mt Lawley, WA 6050, Australia
| | - Jacques Oosthuizen
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia
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22
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Kodali V, Kim KS, Roberts JR, Bowers L, Wolfarth MG, Hubczak J, Xin X, Eye T, Friend S, Stefaniak AB, Leonard SS, Jakubinek M, Erdely A. Influence of Impurities from Manufacturing Process on the Toxicity Profile of Boron Nitride Nanotubes. Small 2022; 18:e2203259. [PMID: 36373669 PMCID: PMC9975644 DOI: 10.1002/smll.202203259] [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] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 08/25/2022] [Indexed: 05/29/2023]
Abstract
The toxicity of boron nitride nanotubes (BNNTs) has been the subject of conflicting reports, likely due to differences in the residuals and impurities that can make up to 30-60% of the material produced based on the manufacturing processes and purification employed. Four BNNTs manufactured by induction thermal plasma process with a gradient of BNNT purity levels achieved through sequential gas purification, water and solvent washing, allowed assessing the influence of these residuals/impurities on the toxicity profile of BNNTs. Extensive characterization including infrared and X-ray spectroscopy, thermogravimetric analysis, size, charge, surface area, and density captured the alteration in physicochemical properties as the material went through sequential purification. The material from each step is screened using acellular and in vitro assays for evaluating general toxicity, mechanisms of toxicity, and macrophage function. As the material increased in purity, there are more high-aspect-ratio particulates and a corresponding distinct increase in cytotoxicity, nuclear factor-κB transcription, and inflammasome activation. There is no alteration in macrophage function after BNNT exposure with all purity grades. The cytotoxicity and mechanism of screening clustered with the purity grade of BNNTs, illustrating that greater purity of BNNT corresponds to greater toxicity.
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Affiliation(s)
- Vamsi Kodali
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, WV, 26506, USA
| | - Keun Su Kim
- Division of Emerging Technologies, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, K1A 0R6, Canada
| | - Jenny R Roberts
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - Lauren Bowers
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - Michael G Wolfarth
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - John Hubczak
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - Xing Xin
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - Tracy Eye
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - Sherri Friend
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - Aleksandr B Stefaniak
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - Stephen S Leonard
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
- Department of Pharmaceutical Science, School of Pharmacy, West Virginia University, Morgantown, WV, 26506, USA
| | - Michael Jakubinek
- Division of Emerging Technologies, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, K1A 0R6, Canada
| | - Aaron Erdely
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, WV, 26506, USA
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Galvis M, Mesa F, Restrepo J. Field-Driven Magnetic Phase Diagram and Vortex Stability in Fe Nanometric Square Prisms. Nanomaterials (Basel) 2022; 12:4243. [PMID: 36500865 PMCID: PMC9741433 DOI: 10.3390/nano12234243] [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] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/10/2022] [Accepted: 11/14/2022] [Indexed: 06/17/2023]
Abstract
In this work, we deal with the zero temperature hysteretic properties of iron (Fe) quadrangular nanoprisms and the size conditions underlying magnetic vortex states formation. Different aspect ratios of a square base prism of thickness t with free boundary conditions were considered in order to summarize our results in a proposal of a field-driven magnetic phase diagram where such vortex states are stable along the hysteresis loops. To do that, a Hamiltonian consisting of exchange, magnetostatic, Zeeman and cubic anisotropy energies was considered. The time dynamics at each magnetic field step was performed by solving the time-dependent Landau-Lifshitz-Gilbert differential equation. The micromagnetic simulations were performed using the Ubermag package based on the Object Oriented Micromagnetic Framework (OOMMF). Circular magnetic textures were also characterized by means of topological charge calculations. The aspect ratio dependencies of the coercive force, nucleation and annihilation fields are also analyzed. Computations agree with related experimental observations and other micromagnetic calculations.
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Affiliation(s)
- Mauricio Galvis
- Group of Magnetism and Simulation G+, Institute of Physics, University of Antioquia, A.A. 1226, Medellín 050010, Colombia
| | - Fredy Mesa
- NanoTech Group, Facultad de Ingeniería y Ciencias Básicas, Fundación Universitaria Los Libertadores, Cra. 16 No. 63a-68, Bogotá 111221, Colombia
| | - Johans Restrepo
- Group of Magnetism and Simulation G+, Institute of Physics, University of Antioquia, A.A. 1226, Medellín 050010, Colombia
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Yun JH, Jeon YJ, Kang MS. Numerical Investigation of the Elastic Properties of Polypropylene/Ultra High Molecular Weight Polyethylene Fiber inside a Composite Material Based on Its Aspect Ratio and Volume Fraction. Polymers (Basel) 2022; 14. [PMID: 36432977 DOI: 10.3390/polym14224851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/02/2022] [Accepted: 11/08/2022] [Indexed: 11/12/2022] Open
Abstract
In this study, the characteristics of a composite material composed of polypropylene (PP) and ultrahigh molecular weight polyethylene (UHMWPE) are investigated. The elastic properties of the PP/UHMWPE composite material composed of short UHMWPE fibers with a low aspect ratio and long UHMWPE fibers with a high aspect ratio are compared and analyzed. In addition, the elastic properties of the PP/UHMWPE composite materials are calculated via finite element analysis and the Halpin-Tsai model by changing the volume fraction of the UHMWPE fibers. The results show that when UHMWPE fibers with a low aspect ratio and volume fraction are used, the results of the modulus of elasticity based on the finite element analysis are consistent with those obtained using the Halpin-Tsai model, although the fiber volume fraction of the UHMWPE fibers increases. Meanwhile, the deviation between the results yielded by both methods increases with the aspect ratio of the fiber. In terms of the shear modulus, the Halpin-Tsai model shows a linear trend. The results from the finite element analysis differ significantly from those of the Halpin-Tsai model owing to the random orientation of the UHMWPE fibers inside the fiber. Using a contour graph constructed based on the finite element analysis results, the aspect ratio and volume fraction of the UHMWPE fibers can be inversely calculated based on the elastic properties when synthesizing a PP/UHMWPE fiber composite. In future studies, the interfacial bonding properties of UHMWPE fibers and PP should be compared and analyzed experimentally.
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Wang Z, Feng Z, Tang H, Wang J, Cai Z, Bi K, Hao Y. Effects of Nanofibers Orientation and Aspect Ratio on Dielectric Properties of Nanocomposites: A Phase-Field Simulation. ACS Appl Mater Interfaces 2022; 14:42513-42521. [PMID: 36095294 DOI: 10.1021/acsami.2c12473] [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: 06/15/2023]
Abstract
Polymer-based dielectrics with high energy storage density are attracting increasing attention due to their wide applications in pulsed-discharge and power conditioning electronic fields. Despite some numerical simulation about effects of horizontally arranged and vertically arranged fibers on dielectric properties of composites already studied, the influence mechanism of the specific orientation and aspect ratio still remains to be studied. In this work, the effects of orientation angles and aspect ratios of nanofiber fillers on breakdown behavior and dielectric properties of composites are theoretically analyzed by the finite element and phase-field method. The results show that the more inclined the nanofiber fillers is, the higher the nominal breakdown strength is, which benefits from the obstruction of the conductive channels by the nanofibers. However, the dielectric constant shows the opposite law, which is the result of the decreased polarization along the electric field direction of the nanofiber fillers. Besides this, by modulating the distribution of local electric field, a higher aspect ratio of nanofiber fillers helps to achieve a much higher breakdown strength with a slight sacrifice of dielectric constant. The present work provides a comprehensive and quantitative understanding of the orientation and aspect ratio of nanofiber fillers on the dielectric and breakdown properties of composites, providing important guidance on optimizing the energy storage performance.
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Affiliation(s)
- Zhaozhen Wang
- State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Zunpeng Feng
- State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Hongsong Tang
- State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Junhao Wang
- State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Ziming Cai
- School of Materials Science and Physics, China University of Mining and Technology, Xuzhou 221116, China
| | - Ke Bi
- State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Yanan Hao
- State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
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Bastida GA, Schnell CN, Mocchiutti P, Solier YN, Inalbon MC, Zanuttini MÁ, Galván MV. Effect of Oxalic Acid Concentration and Different Mechanical Pre-Treatments on the Production of Cellulose Micro/Nanofibers. Nanomaterials (Basel) 2022; 12:2908. [PMID: 36079947 PMCID: PMC9457602 DOI: 10.3390/nano12172908] [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] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 08/19/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
The present work analyzes the effect of process variables and the method of characterization of cellulose micro/nanofibers (CMNFs) obtained by different treatments. A chemical pre-treatment was performed using oxalic acid at 25 wt.% and 50 wt.%. Moreover, for mechanical pre-treatments, a rotary homogenizer or a PFI mill refiner were considered. For the mechanical fibrillation to obtain CMNFs, 5 and 15 passes through a pressurized homogenization were considered. The best results of nanofibrillation yield (76.5%), transmittance (72.1%) and surface charges (71.0 µeq/g CMNF) were obtained using the PFI mill refiner, 50 wt.% oxalic acid and 15 passes. Nevertheless, the highest aspect ratio (length/diameter) determined by Transmission Electron Microscopy (TEM) was found using the PFI mill refiner and 25 wt.% oxalic acid treatment. The aspect ratio was related to the gel point and intrinsic viscosity of CMNF suspensions. The values estimated for gel point agree with those determined by TEM. Moreover, a strong relationship between the intrinsic viscosity [η] of the CMNF dispersions and the corresponding aspect ratio (p) was found (ρ[η] = 0.014 p2.3, R2 = 0.99). Finally, the tensile strength of films obtained from CMNF suspensions was more influenced by the nanofibrillation yield than their aspect ratio.
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Cui L, Wang X, Zhao X, Sun B, Xia T, Hu S. CeO 2 nanoparticles induce pulmonary fibrosis via activating S1P pathway as revealed by metabolomics. Nano Today 2022; 45:101559. [PMID: 36910843 PMCID: PMC9997866 DOI: 10.1016/j.nantod.2022.101559] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
CeO2 nanoparticles (NPs) have been shown to cause lung fibrosis, however, the exact underlying molecular mechanisms are poorly understood. In this study, we have conducted a mass spectrometry-based global metabolomic analysis of human bronchial epithelial BEAS-2B cells treated by CeO2 NPs with different aspect ratios and assessed their toxicity on the bronchial epithelial cells by various cell-based functional assays. Although CeO2 NPs at doses ranging from 12.5 μg/mL to 25 μg/mL displayed low cytotoxicity on the bronchial epithelial cells, the metabolomic analysis revealed a number of metabolites in the cellular metabolic pathways of sphingosine-1-phosphate, fatty acid oxidation, inflammation, etc. were significantly altered by CeO2 NPs, especially those with high aspect ratios. More importantly, the robustness of metabolomics findings was further successfully validated in mouse models upon acute and chronic exposures to CeO2 NPs. Mechanistically, CeO2 NPs upregulated transforming growth factor beta-1 (TGF-β1) levels in BEAS-2B cells in an aspect ratio-dependent manner through enhancing the expression of early growth response protein 1 (EGR-1). In addition, both in vitro and in vivo studies demonstrated that CeO2 NPs significantly induced the expression of sphingosine kinase 1 (SHPK1), phosphorylated Smad2/3 and lung fibrosis markers. Moreover, targeting SPHK1, TGFβ receptor or Smad3 phosphorylation significantly attenuated the fibrosis-promoting effects of CeO2 NPs, and SPHK1-S1P pathway exerted a greater effect on the TGF-β1-mediated lung fibrosis compared to the conventional Smad2/3 pathway. Collectively, our studies have identified the metabolomic changes in BEAS-2B cells exposed to CeO2 NPs with different aspect ratios and revealed the subtle changes in metabolic activities that traditional approaches might have missed. More importantly, we have discovered a previously unknown molecular mechanism underlying CeO2 NP-induced lung fibrosis with different aspect ratios, shedding new insights on the environmental hazard potential of CeO2 NPs.
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Affiliation(s)
- Li Cui
- School of Dentistry, Jonsson Comprehensive Cancer Center, California NanoSystems Institute, University of California, Los Angeles, California 90095, United States
| | - Xiang Wang
- Center for Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, Division of NanoMedicine, Department of Medicine, University of California, Los Angeles, California 90095, United States
| | - Xinyuan Zhao
- Stomatological Hospital, Southern Medical University, Guangzhou, Guangdong 510280, China
| | - Bingbing Sun
- School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Tian Xia
- Center for Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, Division of NanoMedicine, Department of Medicine, University of California, Los Angeles, California 90095, United States
| | - Shen Hu
- School of Dentistry, Jonsson Comprehensive Cancer Center, California NanoSystems Institute, University of California, Los Angeles, California 90095, United States
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Zhou Y, Xu L, Liu M, Qi Z, Wang W, Zhu J, Chen S, Yu K, Su Y, Ding B, Qiu L, Cheng HM. Viscous Solvent-Assisted Planetary Ball Milling for the Scalable Production of Large Ultrathin Two-Dimensional Materials. ACS Nano 2022; 16:10179-10187. [PMID: 35604394 DOI: 10.1021/acsnano.1c11097] [Citation(s) in RCA: 3] [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] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Ball milling is a widely used method to produce graphene and other two-dimensional (2D) materials for both industry and research. Conventional ball milling generates strong impact forces, producing small and thick nanosheets that limit their applications. In this study, a viscous solvent-assisted planetary ball milling method has been developed to produce large thin 2D nanosheets. The viscous solvent simultaneously increases the exfoliation energy (Ee) and lowers the impact energy (Ei). Simulations show a giant ratio of η = Ee/Ei, for the viscous solvent, 2 orders of magnitude larger than that of water. The method provides both a high exfoliation yield of 74%, a high aspect ratio of the generated nanosheets of 571, and a high quality for a representative 2D material of boron nitride nanosheets (BNNSs). The large thin BNNSs can be assembled into high-performance functional films, such as separation membranes and thermally conductive flexible films with some performance parameters better than those 2D nanosheets produced by chemical exfoliation methods.
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Affiliation(s)
- Yicong Zhou
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Lanshu Xu
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Minsu Liu
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
- Monash Suzhou Research Institute (MSRI), Monash University, Suzhou 215000, China
- Foshan (Southern China) Institute for New Materials, Foshan 528200, China
| | - Zheng Qi
- China Iron and Steel Research Institute Group, Beijing 100081, China
| | - Wenbo Wang
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Jiuyi Zhu
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Shaohua Chen
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Kuang Yu
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Yang Su
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Baofu Ding
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Ling Qiu
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
| | - Hui-Ming Cheng
- Shenzhen Geim Graphene Center (SGC), Tsinghua-Berkeley Shenzhen Institute (TBSI), and Tsinghua Shenzhen International Graduate School (TSIGS), Tsinghua University, Shenzhen 51805, China
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
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Hara T, Satow T, Hamano E, Hashimura N, Sumi M, Ikedo T, Ohta T, Takahashi JC, Kataoka H. Aspect Ratio Is Associated with Recanalization after Coiling of Unruptured Intracranial Aneurysms. Neurol Med Chir (Tokyo) 2022; 62:377-383. [PMID: 35831123 PMCID: PMC9464477 DOI: 10.2176/jns-nmc.2022-0052] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The rate of recanalization after coil embolization for unruptured intracranial aneurysms (UIAs) is reported to occur around 11.3%-49%. This study aims to investigate the factors that influence the recanalization after coil embolization for UIAs in our institution. We retrospectively investigated 307 UIAs in 296 patients treated at our institution between April 2004 and December 2016. The stent-used cases were excluded. Cerebral angiography and 3D time-of-flight magnetic resonance angiography (TOF MRA) were used for evaluation of the postoperative occlusion status. Volume embolization ratio (VER), aneurysmal size, neck width, and aspect ratio (AR) were compared between the recanalized and non-recanalized groups. The mean follow-up period ranged from 6 to 172 months (mean: 79.0 ± 39.8 months). Recanalization was noted in 78 (25.4%) aneurysms, and 19 (6.2%) aneurysms required retreatment. There was no aneurysmal rupture during the follow-up period. Univariate analysis showed that the aneurysm size (p < 0.001), neck width (p < 0.001), AR (p = 0.003), and VER (p = 0.012) were associated with recanalization. Multivariate logistic regression analysis showed that the AR (p =0.004) and VER (p =0.015) were significant predictors of recanalization. To summarize, a higher AR and a lower VER could lead to recanalization after coil embolization of UIAs. Careful follow-up is required for coiled aneurysms with these features.
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Affiliation(s)
- Takeshi Hara
- Department of Neurosurgery, National Cerebral and Cardiovascular Center
| | - Tetsu Satow
- Department of Neurosurgery, Kindai University Faculty of Medicine
| | - Eika Hamano
- Department of Neurosurgery, National Cerebral and Cardiovascular Center
| | - Naoki Hashimura
- Department of Neurosurgery, National Cerebral and Cardiovascular Center
| | - Masatake Sumi
- Department of Neurosurgery, National Cerebral and Cardiovascular Center
| | - Taichi Ikedo
- Department of Neurosurgery, National Cerebral and Cardiovascular Center
| | - Tsuyoshi Ohta
- Department of Neurosurgery, National Cerebral and Cardiovascular Center
| | - Jun C Takahashi
- Department of Neurosurgery, Kindai University Faculty of Medicine
| | - Hiroharu Kataoka
- Department of Neurosurgery, National Cerebral and Cardiovascular Center
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Suzuki Y, Sasaki T, Hasegawa H, Ikeda K, Teramura K, Tsukada Y, Nishizawa Y, Ito M. Morphological characteristics of lateral pelvic lymph nodes in locally advanced lower rectal cancer: A retrospective study. Ann Gastroenterol Surg 2022; 6:795-803. [PMID: 36338594 PMCID: PMC9628236 DOI: 10.1002/ags3.12590] [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] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 05/30/2022] [Indexed: 02/09/2023] Open
Abstract
AIM This study aimed to investigate the potential of the size and aspect ratio of metastatic and non-metastatic lateral pelvic lymph nodes (LPLNs) as low-risk markers for locally advanced lower rectal cancer, without treatment by neoadjuvant chemoradiation therapy or LPLN dissection. METHODS This single-center, retrospective cohort study evaluated 310 consecutive patients diagnosed with lower rectal cancer (T: T3/T4, N: any, and M: M0) who underwent curative surgery without neoadjuvant therapies between 2010 and 2018. The harvested LPLNs were categorized into groups A (metastasis-positive lymph nodes), B (metastasis-negative lymph nodes in the area bearing metastasis-positive lymph nodes), C (metastasis-negative lymph nodes in a metastasis-negative area in metastasis-positive patients), and D (lymph nodes in non-metastatic patients). The main outcome measure was the relationship among lymph node size, aspect ratio, and metastasis in the LPLNs. RESULTS Overall, 3962 LPLNs were harvested. The long and short axes and the aspect ratio were significantly longer and higher, respectively, in group A than in the other groups (P < .001). The aspect ratio in group B was significantly higher than that in groups C and D (P < .001). The aspect ratio in group C was significantly higher than that in group D (P < .001). Furthermore, no metastasis-positive lymph nodes had an aspect ratio of less than 0.4. Metastasis-positive LPLNs tended to be larger and rounder than their metastasis-negative counterparts. CONCLUSIONS Metastatic LPLNs in patients with lower rectal cancer are significantly larger and have a higher aspect ratio. Lymph nodes with aspect ratios of <0.4 were metastasis negative.
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Affiliation(s)
- Yushi Suzuki
- Department of Colorectal SurgeryNational Cancer Center Hospital EastChibaJapan
| | - Takeshi Sasaki
- Department of Colorectal SurgeryNational Cancer Center Hospital EastChibaJapan
| | - Hiro Hasegawa
- Department of Colorectal SurgeryNational Cancer Center Hospital EastChibaJapan
| | - Koji Ikeda
- Department of Colorectal SurgeryNational Cancer Center Hospital EastChibaJapan
| | - Koichi Teramura
- Department of Colorectal SurgeryNational Cancer Center Hospital EastChibaJapan
| | - Yuichiro Tsukada
- Department of Colorectal SurgeryNational Cancer Center Hospital EastChibaJapan
| | - Yuji Nishizawa
- Department of Colorectal SurgeryNational Cancer Center Hospital EastChibaJapan
| | - Masaaki Ito
- Department of Colorectal SurgeryNational Cancer Center Hospital EastChibaJapan
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Abstract
(1) Background: In almost all studies of the shape of the human red blood cell (RBC), the suspending medium was a salt solution supplemented with albumin. However, the ratio of thickness across the dimple region to the thickness of the rim (THR) depends on the albumin concentration. Values of the THR in the literature range from 0.27 to 0.627 whereas in the present work it was 0.550 or 0.601 whether measured in plasma or serum. (2) Methods: 9911 RBCs of eight donors were suspended in autologous plasma or serum. Sedimented RBCs were observed under bright field illumination at 416 nm. From the profiles of gray value, the THR was determined. (3) Results: The THR displays a wide distribution within a single blood sample. A direct correlation of THR and spontaneous curvature of the membrane is likely. The variation of the mean THR between different donors is large. The aspect ratio of RBCs viewed face-on ranged on average from 1 to 1.48. In oval RBCs, the rim is thicker along the major axis than along the minor axis, an effect increasing with increasing aspect ratio. Remodeling of the membrane skeleton occurs in vivo with a characteristic time (τ) on the order of 1 h. (4) Conclusions: Consideration of these data in models of RBC behavior might improve the agreement with observations. τ≈1 h suggests a more general type of reference configuration of the membrane skeleton than a stress free shape.
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Affiliation(s)
- Thomas M. Fischer
- Department of Experimental Physics, Saarland University, Campus E2 6, 66123 Saarbrücken, Germany; ; Tel.: +49-160-2293318
- Laboratory for Red Cell Rheology, Krummer Weg 20, 52134 Herzogenrath, Germany
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Cao H, Chen W, Rui Z, Yan C. Effects of cross-sectional area and aspect ratio coupled with orientation on mechanical properties and deformation behavior of Cu nanowires. Nanotechnology 2022; 33:365702. [PMID: 34844233 DOI: 10.1088/1361-6528/ac3e32] [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] [Received: 09/07/2021] [Accepted: 11/29/2021] [Indexed: 06/13/2023]
Abstract
Metal nanomaterials exhibit excellent mechanical properties compared with corresponding bulk materials and have potential applications in various areas. Despite a number of studies of the size effect on Cu nanowires mechanical properties with square cross-sectional, investigations of them in rectangular cross-sectional with various sizes at constant volume are rare, and lack of multifactor coupling effect on mechanical properties and quantitative investigation. In this work, the dependence of mechanical properties and deformation mechanisms of Cu nanowires/nanoplates under tension on cross-sessional area, aspect ratio of cross-sectional coupled with orientation were investigated using molecular dynamics simulations and the semi-empirical expressions related to mechanical properties were proposed. The simulation results show that the Young's modulus and the yield stress sharply increase with the aspect ratio except for the 〈110〉{110}{001} Cu nanowires/nanoplates at the same cross-sectional area. And the Young's modulus increases while the yield stress decreases with the cross-sectional area of Cu nanowires. However, both of them increase with the cross-sectional area of Cu nanoplates. Besides, the Young's modulus increases with the cross-sectional area at all the orientations. The yield stress shows a mildly downward trend except for the 〈111〉 Cu nanowires with increased cross-sectional area. For the Cu nanowires with a small cross-sectional area, the surface force increases with the aspect ratio. In contrast, it decreases with the aspect ratio increase at a large cross-sectional area. At the cross-sectional area of 13.068 nm2, the surface force decreases with the aspect ratio of the 〈110〉 Cu nanowires while it increases at other orientations. The surface force is a linearly decreasing function of the cross-sectional area at different orientations. Quantitative studies show that Young's modulus and yield stress to the aspect ratio of the Cu nanowires satisfy exponent relationship. In addition, the main deformation mechanism of Cu nanowires is the nucleation and propagation of partial dislocations while it is the twinning-dominated reorientation for Cu nanoplates.
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Affiliation(s)
- Hui Cao
- School of Mechanical and Electronical Engineering, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
- Key Laboratory of Digital Manufacturing Technology and Application, the Ministry of Education, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
| | - Wenke Chen
- School of Mechanical and Electronical Engineering, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
| | - Zhiyuan Rui
- School of Mechanical and Electronical Engineering, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
- Key Laboratory of Digital Manufacturing Technology and Application, the Ministry of Education, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
| | - Changfeng Yan
- School of Mechanical and Electronical Engineering, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
- Key Laboratory of Digital Manufacturing Technology and Application, the Ministry of Education, Lanzhou University of Technology, Lanzhou 730050, People's Republic of China
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Xiang Y, Lu K, Wang J, Ding Y, Mao S. Numerical Simulation of the Smoke Recirculation Behavior in Street Canyons with Different Aspect Ratios and Cross-Wind Conditions. Int J Environ Res Public Health 2022; 19:7056. [PMID: 35742305 DOI: 10.3390/ijerph19127056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 06/04/2022] [Accepted: 06/07/2022] [Indexed: 12/10/2022]
Abstract
This study investigated smoke dispersion inside a street canyon in a series of numerical simulations. The building height and street width as well as the cross-wind velocity were changed during the simulation, and the smoke recirculation behavior inside the canyon is presented and discussed. The results show that the smoke recirculation behavior could be distinguished into two different stages, i.e., the “fully recirculation stage” and “semi recirculation stage”, which is strongly determined by the canyon aspect ratio (the building height divided by street width). It was found that the critical wind velocity at which the smoke recirculation would take place was almost constant for an ideal street canyon with an aspect ratio of 1; however, this velocity was decreased with increasing building height or decreasing street width, indicating a much more dangerous circumstance when the aspect ratio is greater. Finally, a new piecewise function is proposed for the critical smoke recirculation velocity for all cases, which can provide some theoretical basis for building designs and emergency rescue for human beings inside the street canyon.
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Hsu WL, Chen YC, Yeh SP, Zeng QC, Huang YW, Wang CM. Review of Metasurfaces and Metadevices: Advantages of Different Materials and Fabrications. Nanomaterials (Basel) 2022; 12:nano12121973. [PMID: 35745310 PMCID: PMC9231017 DOI: 10.3390/nano12121973] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 05/29/2022] [Accepted: 06/03/2022] [Indexed: 01/27/2023]
Abstract
Flat optics, metasurfaces, metalenses, and related materials promise novel on-demand light modulation within ultrathin layers at wavelength scale, enabling a plethora of next-generation optical devices, also known as metadevices. Metadevices designed with different materials have been proposed and demonstrated for different applications, and the mass production of metadevices is necessary for metadevices to enter the consumer electronics market. However, metadevice manufacturing processes are mainly based on electron beam lithography, which exhibits low productivity and high costs for mass production. Therefore, processes compatible with standard complementary metal–oxide–semiconductor manufacturing techniques that feature high productivity, such as i-line stepper and nanoimprint lithography, have received considerable attention. This paper provides a review of current metasurfaces and metadevices with a focus on materials and manufacturing processes. We also provide an analysis of the relationship between the aspect ratio and efficiency of different materials.
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Affiliation(s)
- Wei-Lun Hsu
- Department of Optics and Photonics, National Central University, Taoyuan 32001, Taiwan; (W.-L.H.); (Y.-C.C.); (S.P.Y.); (Q.-C.Z.)
| | - Yen-Chun Chen
- Department of Optics and Photonics, National Central University, Taoyuan 32001, Taiwan; (W.-L.H.); (Y.-C.C.); (S.P.Y.); (Q.-C.Z.)
| | - Shang Ping Yeh
- Department of Optics and Photonics, National Central University, Taoyuan 32001, Taiwan; (W.-L.H.); (Y.-C.C.); (S.P.Y.); (Q.-C.Z.)
| | - Qiu-Chun Zeng
- Department of Optics and Photonics, National Central University, Taoyuan 32001, Taiwan; (W.-L.H.); (Y.-C.C.); (S.P.Y.); (Q.-C.Z.)
| | - Yao-Wei Huang
- Department of Photonics, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
- Correspondence: (Y.-W.H.); (C.-M.W.)
| | - Chih-Ming Wang
- Department of Optics and Photonics, National Central University, Taoyuan 32001, Taiwan; (W.-L.H.); (Y.-C.C.); (S.P.Y.); (Q.-C.Z.)
- Correspondence: (Y.-W.H.); (C.-M.W.)
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Fu L, Shi B, Wen S, Morsch M, Wang G, Zhou Z, Mi C, Sadraeian M, Lin G, Lu Y, Jin D, Chung R. Aspect Ratio of PEGylated Upconversion Nanocrystals Affects the Cellular Uptake In Vitro and In Vivo. Acta Biomater 2022:S1742-7061(22)00305-1. [PMID: 35605956 DOI: 10.1016/j.actbio.2022.05.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 05/11/2022] [Accepted: 05/16/2022] [Indexed: 12/28/2022]
Abstract
The central nervous system (CNS) is protected by the blood-brain barrier (BBB), which acts as a physical barrier to regulate and prevent the uptake of endogenous metabolites and xenobiotics. However, the BBB prevents most non-lipophilic drugs from reaching the CNS following systematic administration. Therefore, there is considerable interest in identifying drug carriers that can maintain the biostability of therapeutic molecules and target their transport across the BBB. In this regard, upconversion nanoparticles (UCNPs) have become popular as a nanoparticle-based solution to this problem, with the additional benefit that they display unique properties for in vivo visualization. The majority of studies to date have explored basic spherical UCNPs for drug delivery applications. However, the biophysical properties of UCNPs, cell uptake and BBB transport have not been thoroughly investigated. In this study, we described a one-pot seed-mediated approach to precisely control longitudinal growth to produce bright UCNPs with various aspect ratios. We have systematically evaluated the effects of the physical aspect ratios and PEGylation of UCNPs on cellular uptake in different cell lines and an in vivo zebrafish model. We found that PEGylated the original UCNPs can enhance their biostability and cell uptake capacity. We identify an optimal aspect ratio for UCNP uptake into several different types of cultured cells, finding that this is generally in the ratio of 2 (length/width). This data provides a crucial clue for further optimizing UCNPs as a drug carrier to deliver therapeutic agents into the CNS. STATEMENT OF SIGNIFICANCE: The central nervous system (CNS) is protected by the blood-brain barrier (BBB), which acts as a highly selective semipermeable barrier of endothelial cells to regulate and prevent the uptake of toxins and pathogens. However, the BBB prevents most non-lipophilic drugs from reaching the CNS following systematic administration. The proposed research is significant because identifying the aspect ratio of drug carriers that maintains the biostability of therapeutic molecules and targets their transport across the blood-brain barrier (BBB) is crucial for designing an efficient drug delivery system. Therefore, this research provides a vital clue for further optimizing UCNPs as drug carriers to deliver therapeutic molecules into the brain.
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Martin E, Valeije A, Sastre F, Velazquez A. Impact of Channels Aspect Ratio on the Heat Transfer in Finned Heat Sinks with Tip Clearance. Micromachines (Basel) 2022; 13:mi13040599. [PMID: 35457904 PMCID: PMC9024436 DOI: 10.3390/mi13040599] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/05/2022] [Accepted: 04/09/2022] [Indexed: 11/16/2022]
Abstract
A 3D numerical study is used to analyze the flow topology and performance, in terms of heat transfer efficiency and required pumping power, of heat sink devices with different channel aspect-ratio in the presence of tip-clearance. Seven different channel aspect ratios AR, from 0.25 to 1.75, were analyzed. The flow Reynolds numbers Re, based on the average velocity evaluated in the device channels region, were in the range of 200 to 1000. Two different behaviors of the global Nusselt were obtained depending on the flow Reynolds number: for Re<600, the heat transfer increased with the channels aspect ratio, e.g., for Re=400, the global Nusselt number increased by 14% for configuration AR=1.75 when compared to configuration AR=0.25. For Re>600, the maximum Nusselt is obtained for the squared-channel configuration, and, for some configurations, flow destabilization to a unsteady regime appeared. For Re=700, Nusselt number reduced when compared with the squared-channel device, 11% and 2% for configurations with AR=0.25 and 1.75, respectively. Dimensionless pressure drop decreased with the aspect ratio for all cases. In the context of micro-devices, where the Reynolds number is small, these results indicate that the use of channels with high aspect-ratios is more beneficial, both in terms of thermal and dynamic efficiency.
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Affiliation(s)
- Elena Martin
- Departamento de Ingeniería Mecánica, Máquinas y Motores Térmicos y Fluidos, Escuela de Ingeniería Industrial, Campus Marcosende, Universidade de Vigo, 36310 Vigo, Spain;
- Correspondence:
| | - Alejandro Valeije
- Departamento de Ingeniería Mecánica, Máquinas y Motores Térmicos y Fluidos, Escuela de Ingeniería Industrial, Campus Marcosende, Universidade de Vigo, 36310 Vigo, Spain;
| | - Francisco Sastre
- Fluid Mechanics and Aerospace Propulsion Department, Universidad Politécnica de Madrid, Plaza del Cardenal Cisneros 3, 28040 Madrid, Spain; (F.S.); (A.V.)
| | - Angel Velazquez
- Fluid Mechanics and Aerospace Propulsion Department, Universidad Politécnica de Madrid, Plaza del Cardenal Cisneros 3, 28040 Madrid, Spain; (F.S.); (A.V.)
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Mei X, Zhang L, Zhu Y. Investigation into the effect of the aspect ratio of cylindrical surface microstructure on von Willebrand factor damage. Int J Artif Organs 2022; 45:322-330. [PMID: 35075935 DOI: 10.1177/03913988211070309] [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] [Indexed: 11/16/2022]
Abstract
Hemorrhagic episodes in patients carrying mechanical circulatory support represent a severe clinical complication. These bleeding episodes may originate from a reduced functionality of von Willebrand factor (VWF), a multimer protein pertinent to form a hemostatic plug. The reduced functionality is due to increased loss of high molecular weight von Willebrand factor multimers (HMWM-VWF), a phenomenon that is facilitated by device-induced increases in shear stress to which VWF is exposed. However, in addition to the mechanics factors, VWF damage may also be affected by interface factors, including the properties of bulk material and the surface characteristics. In this study, the effect of cylindrical surface microstructure topography on VWF damage was investigated. In the 1 to 9 range, the high aspect ratio surface features were constructed on the polycarbonate (PC) films. The topographic surfaces were fabricated by 3D printing casting on a template. A roller pump circulation platform was built to conduct in vitro experiments. VWF antigen (VWF-Ag) and VWF ristocetin cofactor activity (VWF-Rico) on these topographic surfaces were quantified by enzyme-linked immunosorbent assay (ELISA), the loss of HMWM-VWF was quantified by immunoblotting. The lower loss of HMWM-VWF was observed on surfaces with high aspect ratio compared to the pristine PC templates and surfaces with low aspect ratio, while VWF-Ag was nearly unchanged. The topographical parameters found to significantly reduce the loss of HMWM-VWF were high aspect ratio structures of more than 5. The results signify that topographical manipulation of surfaces is a feasible approach for reducing the loss of HMWM-VWF.
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Affiliation(s)
- Xu Mei
- Artificial Organ Technology Lab, Bio-manufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Liudi Zhang
- Artificial Organ Technology Lab, Bio-manufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Yuxin Zhu
- Artificial Organ Technology Lab, Bio-manufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
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Yang X, Gu M, Wei Q, Zhang Y, Wu S, Wu Q, Hu X, Zhao W, Zhou G. Photo-Embossed Surface Relief Structures with Improved Aspect Ratios and Their Applications in Liquid Crystal Devices. Polymers (Basel) 2022; 14:polym14010171. [PMID: 35012193 PMCID: PMC8747292 DOI: 10.3390/polym14010171] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 12/28/2021] [Accepted: 12/29/2021] [Indexed: 02/04/2023] Open
Abstract
Photo-embossing has been developed as a convenient and economical method for creating complex surface relief structures in polymer films. The pursuit for large aspect ratios of the photo-embossed structures has never stopped. Here, we demonstrate a simple strategy to obtain improved aspect ratios by adding a quick solvent developing step into the photo-embossing process. A good solvent for the monomer is used to remove unreacted monomers from the unexposed region, resulting in deepened valleys of the surface reliefs. In a polymer film as thin as 2.5 µm, the height of the surface reliefs can be increased by a factor of three to around 1.0 µm. This strategy is also shown to be compatible with other methods used to improve the aspect ratios of the photo-embossed structures. Lastly, we employ these surface relief structures in the fabrication of liquid crystal (LC) devices and investigate their performances for visible light regulation.
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Affiliation(s)
- Xiulan Yang
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, No. 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; (X.Y.); (M.G.); (Q.W.); (Y.Z.); (S.W.); (X.H.); (G.Z.)
| | - Minzhao Gu
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, No. 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; (X.Y.); (M.G.); (Q.W.); (Y.Z.); (S.W.); (X.H.); (G.Z.)
| | - Qunmei Wei
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, No. 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; (X.Y.); (M.G.); (Q.W.); (Y.Z.); (S.W.); (X.H.); (G.Z.)
| | - Yang Zhang
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, No. 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; (X.Y.); (M.G.); (Q.W.); (Y.Z.); (S.W.); (X.H.); (G.Z.)
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China
| | - Sihan Wu
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, No. 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; (X.Y.); (M.G.); (Q.W.); (Y.Z.); (S.W.); (X.H.); (G.Z.)
| | - Qin Wu
- Zhuhai Singyes New Materials Technology Co., Ltd., No. 9 Jinzhu Road, Technology Innovation Coast, High-Tech Development Zone, Jinding Town, Zhuhai 519000, China;
| | - Xiaowen Hu
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, No. 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; (X.Y.); (M.G.); (Q.W.); (Y.Z.); (S.W.); (X.H.); (G.Z.)
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China
| | - Wei Zhao
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, No. 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; (X.Y.); (M.G.); (Q.W.); (Y.Z.); (S.W.); (X.H.); (G.Z.)
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China
- Correspondence:
| | - Guofu Zhou
- SCNU-TUE Joint Lab of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University, No. 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; (X.Y.); (M.G.); (Q.W.); (Y.Z.); (S.W.); (X.H.); (G.Z.)
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China
- Shenzhen Guohua Optoelectronics Tech. Co., Ltd., Shenzhen 518110, China
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Sadhukhan S, Nandi SK. On the origin of universal cell shape variability in confluent epithelial monolayers. eLife 2022; 11:76406. [PMID: 36563034 PMCID: PMC9833828 DOI: 10.7554/elife.76406] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 12/22/2022] [Indexed: 12/24/2022] Open
Abstract
Cell shape is fundamental in biology. The average cell shape can influence crucial biological functions, such as cell fate and division orientation. But cell-to-cell shape variability is often regarded as noise. In contrast, recent works reveal that shape variability in diverse epithelial monolayers follows a nearly universal distribution. However, the origin and implications of this universality remain unclear. Here, assuming contractility and adhesion are crucial for cell shape, characterized via aspect ratio (r), we develop a mean-field analytical theory for shape variability. We find that all the system-specific details combine into a single parameter α that governs the probability distribution function (PDF) of r; this leads to a universal relation between the standard deviation and the average of r. The PDF for the scaled r is not strictly but nearly universal. In addition, we obtain the scaled area distribution, described by the parameter μ. Information of α and μ together can distinguish the effects of changing physical conditions, such as maturation, on different system properties. We have verified the theory via simulations of two distinct models of epithelial monolayers and with existing experiments on diverse systems. We demonstrate that in a confluent monolayer, average shape determines both the shape variability and dynamics. Our results imply that cell shape distribution is inevitable, where a single parameter describes both statics and dynamics and provides a framework to analyze and compare diverse epithelial systems. In contrast to existing theories, our work shows that the universal properties are consequences of a mathematical property and should be valid in general, even in the fluid regime.
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40
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Yang H, Zheng X, Zheng Z, He J, Kong D, Ding K, Zhou S. Precise Control of Shape-Variable Nanomicelles in Nanofibers Reveals the Enhancement Mechanism of Passive Delivery. ACS Appl Mater Interfaces 2021; 13:54715-54726. [PMID: 34757716 DOI: 10.1021/acsami.1c15858] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nowadays, the development of nanoparticles is known to be mainly associated with enhancement of the targeted delivery of the active component to solid tumors. However, the lack of understanding of the nanoparticle morphology restricts the transport efficiency of various nanocarriers, especially offers no consistent mechanism for the delivery. Here, we demonstrate the principles of enhancement of passive delivery utilizing the precise control and analysis of shape-switchable nanomicelles without any functional addition. We successfully regulated the nanomicelle shape with various aspect ratios in the electrospun nanofiber matrix and devised a stretching phase diagram. Using the vascular leakage model, visual laser spectrum, and image analysis in the simulated scene, we found that the deformed nanomicelles with high aspect ratios along with lower equivalent volumes were significantly beneficial to the passive delivery. Further, the enhanced permeability of the shape-variable nanomicelles in the recovering state was up to 4 times of that observed before recovery. Our results challenge the current consensus of passive targeting and provide an important guidance for the design of nanoparticle morphology and active addition in cancer nanomedicine.
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Affiliation(s)
- Huikai Yang
- School of Materials Science and Engineering, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Xiaotong Zheng
- School of Materials Science and Engineering, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Zhiwen Zheng
- School of Materials Science and Engineering, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Jing He
- School of Materials Science and Engineering, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Degang Kong
- School of Materials Science and Engineering, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Kai Ding
- School of Materials Science and Engineering, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
| | - Shaobing Zhou
- School of Materials Science and Engineering, Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China
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41
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Yang HY, Chuquer A, Han SH, Gaudel GS, Pham XH, Kim HM, Yun WJ, Jun BH, Rho WY. Optimizing the Aspect Ratio of Nanopatterned Mesoporous TiO 2 Thin-Film Layer to Improve Energy Conversion Efficiency of Perovskite Solar Cells. Int J Mol Sci 2021; 22:12235. [PMID: 34830119 DOI: 10.3390/ijms222212235] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/05/2021] [Accepted: 11/09/2021] [Indexed: 11/27/2022] Open
Abstract
The energy conversion efficiency (ECE) (η), current density (Jsc), open-circuit voltage (Voc), and fill factor (ff) of perovskite solar cells were studied by using the transmittance of a nanopatterned mesoporous TiO2 (mp-TiO2) thin-film layer. To improve the ECE of perovskite solar cells, a mp-TiO2 thin-film layer was prepared to be used as an electron transport layer (ETL) via the nanoimprinting method for nanopatterning, which was controlled by the aspect ratio. The nanopatterned mp-TiO2 thin-film layer had a uniform and well-designed structure, and the diameter of nanopatterning was 280 nm. The aspect ratio was controlled at the depths of 75, 97, 127, and 167 nm, and the perovskite solar cell was fabricated with different depths. The ECE of the perovskite solar cells with the nanopatterned mp-TiO2 thin-film layer was 14.50%, 15.30%, 15.83%, or 14.24%, which is higher than that of a non-nanopatterned mp-TiO2 thin-film layer (14.07%). The enhancement of ECE was attributed to the transmittance of the nanopatterned mp-TiO2 thin-film layer that is due to the improvement of the electron generation. As a result, better electron generation affected the electron density, and Jsc increased the Voc, and ff of perovskite solar cells.
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42
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Yang X, Bonnett BL, Spiering GA, Cornell HD, Gibbons BJ, Moore RB, Foster EJ, Morris AJ. Understanding the Mechanical Reinforcement of Metal-Organic Framework-Polymer Composites: The Effect of Aspect Ratio. ACS Appl Mater Interfaces 2021; 13:51894-51905. [PMID: 34086436 DOI: 10.1021/acsami.1c05430] [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: 06/12/2023]
Abstract
The aspect ratio (AR) of filler particles is one of the most critical determinants for the mechanical properties of particle-reinforced polymer composites. However, it has been challenging to solely study the effect of particle AR due to the difficulties of controlling AR without altering the physical and chemical properties of the particle. Herein, we synthesized PCN-222, a zirconium-based porphyrinic metal-organic framework (MOF) with preferential longitudinal growth as a series of particles with ARs increasing from 3.4 to 54. The synthetic MOF conditions allowed for the chemical properties of the particles to remain constant over the series. The particles were employed as reinforcers for poly(methyl methacrylate) (PMMA). MOF-polymer composite films were fabricated using doctor-blading techniques, which facilitated particle dispersion and alignment in the PMMA matrix, as revealed by optical microscopy and wide-angle X-ray diffraction. Mechanical measurements showed that both elastic and dynamic moduli increased with particle AR and particle concentrations but started to decrease as particle loading increased beyond 0.5 wt % (1.12 vol %). The data obtained at low particle loadings were fitted well with the Halpin-Tsai model. In contrast, the percolation model and the Cox model were unable to adequately fit the data, indicating the mechanical reinforcement in our system mainly originated from efficient load transfer between particles and the matrix in the particle orienting direction. Finally, we showed that the thermal stability of composite films increased with the addition of MOF particles because of the high thermal degradation temperature and restricted polymer chain mobility.
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Affiliation(s)
- Xiaozhou Yang
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Brittany L Bonnett
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Glenn A Spiering
- Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Hannah D Cornell
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Bradley J Gibbons
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Robert B Moore
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
- Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - E Johan Foster
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
- Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
- Department of Chemical and Biological Engineering, University of British Columbia, British Columbia, Vancouver, V6T 1Z3, Canada
| | - Amanda J Morris
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
- Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
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43
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Jbeili M, Zhang J. Effects of Microscopic Properties on Macroscopic Thermal Conductivity for Convective Heat Transfer in Porous Materials. Micromachines (Basel) 2021; 12:1369. [PMID: 34832781 DOI: 10.3390/mi12111369] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 10/31/2021] [Accepted: 11/05/2021] [Indexed: 01/06/2023]
Abstract
Porous materials are widely used in many heat transfer applications. Modeling porous materials at the microscopic level can accurately incorporate the detailed structure and substance parameters and thus provides valuable information for the complex heat transfer processes in such media. In this study, we use the generalized periodic boundary condition for pore-scale simulations of thermal flows in porous materials. A two-dimensional porous model consisting of circular solid domains is considered, and comprehensive simulations are performed to study the influences on macroscopic thermal conductivity from several microscopic system parameters, including the porosity, Reynolds number, and periodic unit aspect ratio and the thermal conductance at the solid–fluid interface. Our results show that, even at the same porosity and Reynolds number, the aspect ratio of the periodic unit and the interfacial thermal conductance can significantly affect the macroscopic thermal behaviors of porous materials. Qualitative analysis is also provided to relate the apparent thermal conductivity to the complex flow and temperature distributions in the microscopic porous structure. The method, findings and discussions presented in this paper could be useful for fundamental studies, material development, and engineering applications of porous thermal flow systems.
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Villarreal R, Lin PC, Faraji F, Hassani N, Bana H, Zarkua Z, Nair MN, Tsai HC, Auge M, Junge F, Hofsaess HC, De Gendt S, De Feyter S, Brems S, Åhlgren EH, Neyts EC, Covaci L, Peeters F, Neek-Amal M, Pereira LMC. Breakdown of Universal Scaling for Nanometer-Sized Bubbles in Graphene. Nano Lett 2021; 21:8103-8110. [PMID: 34519503 PMCID: PMC9286314 DOI: 10.1021/acs.nanolett.1c02470] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report the formation of nanobubbles on graphene with a radius of the order of 1 nm, using ultralow energy implantation of noble gas ions (He, Ne, Ar) into graphene grown on a Pt(111) surface. We show that the universal scaling of the aspect ratio, which has previously been established for larger bubbles, breaks down when the bubble radius approaches 1 nm, resulting in much larger aspect ratios. Moreover, we observe that the bubble stability and aspect ratio depend on the substrate onto which the graphene is grown (bubbles are stable for Pt but not for Cu) and trapped element. We interpret these dependencies in terms of the atomic compressibility of the noble gas as well as of the adhesion energies between graphene, the substrate, and trapped atoms.
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Affiliation(s)
| | - Pin-Cheng Lin
- Quantum
Solid State Physics, KU Leuven, 3001 Leuven, Belgium
| | - Fahim Faraji
- Research
group PLASMANT, Department of Chemistry, Universiteit Antwerpen (UIA), 2610 Antwerpen, Belgium
- Departement
Natuurkunde, Universiteit Antwerpen (UIA), 2610 Antwerpen, Belgium
| | - Nasim Hassani
- Department
of Physics, Shahid Rajaee Teacher Training
University, 16875-163 Lavizan, Tehran, Iran
| | - Harsh Bana
- Quantum
Solid State Physics, KU Leuven, 3001 Leuven, Belgium
| | - Zviadi Zarkua
- Quantum
Solid State Physics, KU Leuven, 3001 Leuven, Belgium
| | - Maya N. Nair
- CUNY
Advanced Science Research Center, 85 St. Nicholas Terrace, New York, New York 10031, United States
| | - Hung-Chieh Tsai
- imec vzw (Interuniversitair
Micro-Electronica Centrum), 3001 Leuven, Belgium
- Department
of Chemistry, Division of Molecular Design and Synthesis, KU Leuven, 3001 Leuven, Belgium
| | - Manuel Auge
- II.Institute
of Physics, University of Göttingen, 37077 Göttingen, Germany
| | - Felix Junge
- II.Institute
of Physics, University of Göttingen, 37077 Göttingen, Germany
| | - Hans C. Hofsaess
- II.Institute
of Physics, University of Göttingen, 37077 Göttingen, Germany
| | - Stefan De Gendt
- imec vzw (Interuniversitair
Micro-Electronica Centrum), 3001 Leuven, Belgium
- Department
of Chemistry, Division of Molecular Design and Synthesis, KU Leuven, 3001 Leuven, Belgium
| | - Steven De Feyter
- Department
of Chemistry, Division of Molecular Imaging and Photonics, KU Leuven, 3001 Leuven, Belgium
| | - Steven Brems
- imec vzw (Interuniversitair
Micro-Electronica Centrum), 3001 Leuven, Belgium
| | | | - Erik C. Neyts
- Research
group PLASMANT, Department of Chemistry, Universiteit Antwerpen (UIA), 2610 Antwerpen, Belgium
| | - Lucian Covaci
- Departement
Natuurkunde, Universiteit Antwerpen (UIA), 2610 Antwerpen, Belgium
| | - François
M. Peeters
- Departement
Natuurkunde, Universiteit Antwerpen (UIA), 2610 Antwerpen, Belgium
| | - Mehdi Neek-Amal
- Department
of Physics, Shahid Rajaee Teacher Training
University, 16875-163 Lavizan, Tehran, Iran
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Hussein AA, Ragab SA, Hajj MR, Patil MJ. Material and geometric effects on propulsion of a fish tail. Bioinspir Biomim 2021; 16:066008. [PMID: 34450610 DOI: 10.1088/1748-3190/ac220e] [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] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
We investigate the effects of material flexibility and aspect ratio on the propulsion of flapping tails. The tail, which is assumed to deform in the bending direction only, is modeled using the Euler-Bernoulli beam theory. The hydrodynamic loads generated by the flapping motion are calculated using the three-dimensional unsteady vortex lattice method. The finite element method is used to solve the coupled time-dependent equations of motion using an implicit solver for time integration. The results show improvement in the thrust and propulsive efficiency over a specific range of non-dimensional flexibility defined by the ratio of the elastic forces to fluid pressure forces. Structural and flow characteristics associated with the improved performance are discussed. As for geometric effects, the performance depends on the excitation frequency. At low frequencies, the improvement is continuous with increasing the aspect ratio in a manner similar to that of rigid tails. At higher frequencies, the improvement is limited to a region defined by aspect ratios that are less than 0.5. The extent of the improvement depends on the flexibility.
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Affiliation(s)
- Ahmed A Hussein
- Aerospace and Ocean Engineering, Virginia Tech, Blacksburg, VA 24061, United States of America
| | - Saad A Ragab
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, United States of America
| | - Muhammad R Hajj
- Civil, Environmental and Ocean Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, United States of America
| | - Mayuresh J Patil
- Aerospace and Ocean Engineering, Virginia Tech, Blacksburg, VA 24061, United States of America
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Wang Y, Zhu S, Li H, Zhou L, Yi W. Experimental and Numerical Study on the Compressive Failure of Composite Laminates with Fiber Waviness Defects. Polymers (Basel) 2021; 13:3204. [PMID: 34641020 DOI: 10.3390/polym13193204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 09/12/2021] [Accepted: 09/18/2021] [Indexed: 12/02/2022] Open
Abstract
Fiber waviness defects are found in the inner surface of the hat-shaped stringers manufactured by a process system. In order to establish the acceptance criterion for the stringers with the fiber waviness defects, experimental testing and numerical simulation were carried out in this study. Specially induced fiber waviness defects of four pre-defined severity levels were manufactured and tested. A maximum of a 58.1% drop in compressive failure load is observed for the most severe level in the experimental results. A finite element model with progressive damage method and cohesive zone technique was developed to simulate the failure process and the impact of fiber waviness defects. The numerical simulation results of compressive failure load have a good agreement with experimental results qualitatively and quantitatively. In addition, two simple parameters, i.e., aspect ratio A/H and the number of plies with fiber waviness, are proposed to characterize the influence of the fiber waviness on the compressive failure load for the purpose of fast engineering quality checks.
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Li J, Wang X, Chang CH, Jiang J, Liu Q, Liu X, Liao YP, Ma T, Meng H, Xia T. Nanocellulose Length Determines the Differential Cytotoxic Effects and Inflammatory Responses in Macrophages and Hepatocytes. Small 2021; 17:e2102545. [PMID: 34363305 PMCID: PMC8460616 DOI: 10.1002/smll.202102545] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/23/2021] [Indexed: 05/18/2023]
Abstract
Nanocellulose including cellulose nanocrystal (CNC) and cellulose nanofiber (CNF) has attracted much attention due to its exceptional mechanical, chemical, and rheological properties. Although considered biocompatible, recent reports have demonstrated nanocellulose can be hazardous, including serving as drug carriers that accumulate in the liver. However, the nanocellulose effects on liver cells, including Kupffer cells (KCs) and hepatocytes are unclear. Here, the toxicity of nanocellulose with different lengths is compared, including the shorter CNCs (CNC-1, CNC-2, and CNC-3) and longer CNF (CNF-1 and CNF-2), to liver cells. While all CNCs triggered significant cytotoxicity in KCs and only CNC-2 induced toxicity to hepatocytes, CNFs failed to induce significant cytotoxicity due to their minimal cellular uptake. The phagocytosis of CNCs by KCs induced mitochondria ROS generation, caspase-3/7 activation, and apoptotic cell death as well as lysosomal damage, cathepsin B release, NLRP3 inflammasome and caspase-1 activation, and IL-1β production. The cellular uptake of CNC-2 by hepatocytes is through clathrin-mediated endocytosis, and it induced the caspase-3/7-mediated apoptosis. CNC-2 shows the highest levels of uptake and cytotoxicity among CNCs. These results demonstrate the length-dependent mechanisms of toxicity on liver cells in a cell type-dependent fashion, providing information to safely use nanocellulose for biomedical applications.
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Affiliation(s)
- Jiulong Li
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Xiang Wang
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
- Division of NanoMedicine, Department of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Chong Hyun Chang
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Jinhong Jiang
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Qi Liu
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Xiangsheng Liu
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Yu-Pei Liao
- Division of NanoMedicine, Department of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Tiancong Ma
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Huan Meng
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
- Division of NanoMedicine, Department of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Tian Xia
- Center of Environmental Implications of Nanotechnology (UC CEIN), California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
- Division of NanoMedicine, Department of Medicine, University of California, Los Angeles, CA, 90095, USA
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Venkataraman S, Hefferon K. Application of Plant Viruses in Biotechnology, Medicine, and Human Health. Viruses 2021; 13:1697. [PMID: 34578279 PMCID: PMC8473230 DOI: 10.3390/v13091697] [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] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 07/02/2021] [Accepted: 07/12/2021] [Indexed: 01/06/2023] Open
Abstract
Plant-based nanotechnology programs using virus-like particles (VLPs) and virus nanoparticles (VNPs) are emerging platforms that are increasingly used for a variety of applications in biotechnology and medicine. Tobacco mosaic virus (TMV) and potato virus X (PVX), by virtue of having high aspect ratios, make ideal platforms for drug delivery. TMV and PVX both possess rod-shaped structures and single-stranded RNA genomes encapsidated by their respective capsid proteins and have shown great promise as drug delivery systems. Cowpea mosaic virus (CPMV) has an icosahedral structure, and thus brings unique benefits as a nanoparticle. The uses of these three plant viruses as either nanostructures or expression vectors for high value pharmaceutical proteins such as vaccines and antibodies are discussed extensively in the following review. In addition, the potential uses of geminiviruses in medical biotechnology are explored. The uses of these expression vectors in plant biotechnology applications are also discussed. Finally, in this review, we project future prospects for plant viruses in the fields of medicine, human health, prophylaxis, and therapy of human diseases.
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Affiliation(s)
| | - Kathleen Hefferon
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3B2, Canada;
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Asil D, Haciefendioğlu T. Aspect ratio dependent air stability of PbSe nanorods and photovoltaic applications. Turk J Chem 2021; 45:905-913. [PMID: 34385875 PMCID: PMC8326480 DOI: 10.3906/kim-2012-6] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 03/31/2021] [Indexed: 11/18/2022] Open
Abstract
Development of unique strategies to overcome Shockley–Queisser (SQ) limit in solar cells has gained a great deal of interest. Multiple exciton generation (MEG) process has been considered as one of the best approaches to the SQ limitation. In this respect, PbSe quantum dots (QDs) and nanorods (NRs) have been regarded as promising solar energy harvesting materials owing to their noticeable MEG yields. Although air stability has been regarded as one of the main disadvantage of PbSe QDs, no study has pointed out to the air sensitivity of PbSe NRs yet. Here, we reveal the effect of aspect ratio on air sensitivity and optical properties of PbSe NRs and discover that NRs with higher aspect ratios are more air stable, attributed to the reduced density of NR ends with air sensitive {100} facets. Furthermore, a band offset was created by utilization of tetrabutylammonium iodide and 1,2-ethanedithiol ligands in cell designs. We found that solar cells based on pristine PbSe NRs are limited by low open circuit voltages due to leakage current pathways. On the other hand, modified cells comprising light absorbing layers prepared by blending NRs and QDs and hole transporting QD layer exhibit a 10-fold improvement in solar cell efficiency.
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Affiliation(s)
- Demet Asil
- Department of Chemistry, Faculty of Arts and Science, Middle East Technical University, Ankara Turkey.,The Center for Solar Energy Research and Application, Middle East Technical University, Ankara Turkey.,Department of Micro and Nanotechnology, Middle East Technical University, Ankara Turkey.,Department of Polymer Science and Technology, Middle East Technical University, Ankara Turkey
| | - Tuğba Haciefendioğlu
- Department of Chemistry, Faculty of Arts and Science, Middle East Technical University, Ankara Turkey
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Fernandes J, Kang S. Numerical Study on the Surface Plasmon Resonance Tunability of Spherical and Non-Spherical Core-Shell Dimer Nanostructures. Nanomaterials (Basel) 2021; 11:nano11071728. [PMID: 34209155 PMCID: PMC8308162 DOI: 10.3390/nano11071728] [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] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/26/2021] [Accepted: 06/28/2021] [Indexed: 11/24/2022]
Abstract
The near-field enhancement and localized surface plasmon resonance (LSPR) on the core-shell noble metal nanostructure surfaces are widely studied for various biomedical applications. However, the study of the optical properties of new plasmonic non-spherical nanostructures is less explored. This numerical study quantifies the optical properties of spherical and non-spherical (prolate and oblate) dimer nanostructures by introducing finite element modelling in COMSOL Multiphysics. The surface plasmon resonance peaks of gold nanostructures should be understood and controlled for use in biological applications such as photothermal therapy and drug delivery. In this study, we find that non-spherical prolate and oblate gold dimers give excellent tunability in a wide range of biological windows. The electromagnetic field enhancement and surface plasmon resonance peak can be tuned by varying the aspect ratio of non-spherical nanostructures, the refractive index of the surrounding medium, shell thickness, and the distance of separation between nanostructures. The absorption spectra exhibit considerably greater dependency on the aspect ratio and refractive index than the shell thickness and separation distance. These results may be essential for applying the spherical and non-spherical nanostructures to various absorption-based applications.
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