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High-performance flexible p-type Ce-filled Fe 3CoSb 12 skutterudite thin film for medium-to-high-temperature applications. Nat Commun 2024; 15:4242. [PMID: 38762562 PMCID: PMC11102547 DOI: 10.1038/s41467-024-48677-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 05/10/2024] [Indexed: 05/20/2024] Open
Abstract
P-type Fe3CoSb12-based skutterudite thin films are successfully fabricated, exhibiting high thermoelectric performance, stability, and flexibility at medium-to-high temperatures, based on preparing custom target materials and employing advanced pulsed laser deposition techniques to address the bonding challenge between the thin films and high-temperature flexible polyimide substrates. Through the optimization of fabrication processing and nominal doping concentration of Ce, the thin films show a power factor of >100 μW m-1 K-2 and a ZT close to 0.6 at 653 K. After >2000 bending cycle tests at a radius of 4 mm, only a 6 % change in resistivity can be observed. Additionally, the assembled p-type Fe3CoSb12-based flexible device exhibits a power density of 135.7 µW cm-2 under a temperature difference of 100 K with the hot side at 623 K. This work fills a gap in the realization of flexible thermoelectric devices in the medium-to-high-temperature range and holds significant practical application value.
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Boosting thermoelectric performance of single-walled carbon nanotubes-based films through rational triple treatments. Nat Commun 2024; 15:3426. [PMID: 38654020 DOI: 10.1038/s41467-024-47417-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 04/02/2024] [Indexed: 04/25/2024] Open
Abstract
Single-walled carbon nanotubes (SWCNTs)-based thermoelectric materials, valued for their flexibility, lightweight, and cost-effectiveness, show promise for wearable thermoelectric devices. However, their thermoelectric performance requires significant enhancement for practical applications. To achieve this goal, in this work, we introduce rational "triple treatments" to improve the overall performance of flexible SWCNT-based films, achieving a high power factor of 20.29 µW cm-1 K-2 at room temperature. Ultrasonic dispersion enhances the conductivity, NaBH4 treatment reduces defects and enhances the Seebeck coefficient, and cold pressing significantly densifies the SWCNT films while preserving the high Seebeck coefficient. Also, bending tests confirm structural stability and exceptional flexibility, and a six-legged flexible device demonstrates a maximum power density of 2996 μW cm-2 at a 40 K temperature difference, showing great application potential. This advancement positions SWCNT films as promising flexible thermoelectric materials, providing insights into high-performance carbon-based thermoelectrics.
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[Clinical effect of modified vertical rectus abdominis myocutaneous flap in repairing skin and soft tissue defects after abdominoperineal resection for rectal cancer]. ZHONGHUA SHAO SHANG YU CHUANG MIAN XIU FU ZA ZHI 2024; 40:57-63. [PMID: 38296237 DOI: 10.3760/cma.j.cn501225-20231030-00156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/15/2024]
Abstract
Objective: To investigate the clinical effect of the modified vertical rectus abdominis myocutaneous flap in repairing the skin and soft tissue defect after abdominoperineal resection for rectal cancer. Methods: This study was a retrospective observational study. From June 2019 to July 2022, five male patients with low rectal cancer who were conformed to the inclusion criteria were admitted to the Department of Basic Surgery of Xiangya Hospital of Central South University, with ages ranging from 65 to 70 years and the sizes of the perianal skin ulcers ranging from 5 cm×4 cm to 11 cm×9 cm, and all of them underwent abdominoperineal resection. The secondary skin and soft tissue defects in the perineum with an area of 8 cm×6 cm-14 cm×12 cm (with the depth of pelvic floor dead space being 10-15 cm) were repaired intraoperatively with transplantation of modified vertical rectus abdominis myocutaneous flaps with the skin area being 9 cm×7 cm-16 cm×12 cm, the volume of the muscle being 18 cm×10 cm×5 cm-20 cm×12 cm×5 cm, and the vessel pedicle being 18-20 cm in length. During the operation, most of the anterior sheath of the rectus abdominis muscle was retained, the flap was transferred to the recipient area through the abdominal cavity, the remaining anterior sheaths of the rectus abdominis muscle on both sides of the donor area were repeatedly folded and sutured, the free edge of the transverse fascia of the abdomen was sutured with the anterior sheath of the rectus abdominis muscle, and the donor area skin was directly sutured. After the operation, the survival of the transplanted myocutaneous flap was observed. The occurrence of complications in the perineal recipient area was recorded within 2 weeks after the operation. The recovery of the perineal recipient area and the abdominal donor area was observed during follow-up, and the occurrence of complications in the donor area of the abdomen as well as the recurrence of tumors and metastasis were recorded. Results: All transplanted myocutaneous flaps in 5 patients survived after surgery. One patient had dehiscence of the incision in the perineal recipient area 2 days after surgery, which healed after 7 d with intermittent dressing changes and routine vacuum sealing drainage treatment. In the other 4 patients, no complications such as incisional rupture, incisional infection, or fat liquefaction occurred in the perineal recipient area within 2 weeks after surgery. Follow-up for 6-12 months after discharge showed that the skin of the perineal recipient area had good color, texture, and elasticity, and was not bloated in appearance; linear scars were left in the perineal recipient area and the abdominal donor area without obvious scar hyperplasia or hyperpigmentation; no complications such as incisional rupture, incisional infection, intestinal adhesion, intestinal obstruction, or weakening of the abdominal wall strength occurred in the abdominal donor area, and the abdominal appearance was good with no localized bulge or formation of abdominal hernia; there was no local recurrence of tumor or metastasis in any patient. Conclusions: The surgical approach of using the modified vertical rectus abdominis myocutaneous flap to repair the skin and soft tissue defects after abdominoperineal resection for rectal cancer is relatively simple in operation, can achieve good postoperative appearances of the donor and recipient areas with few complications, and is worthy of clinical promotion.
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Decoupling Carrier-Phonon Scattering Boosts the Thermoelectric Performance of n-Type GeTe-Based Materials. J Am Chem Soc 2024; 146:1681-1689. [PMID: 38178655 DOI: 10.1021/jacs.3c12546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
The coupled relationship between carrier and phonon scattering severely limits the thermoelectric performance of n-type GeTe materials. Here, we provide an efficient strategy to enlarge grains and induce vacancy clusters for decoupling carrier-phonon scattering through the annealing optimization of n-type GeTe-based materials. Specifically, boundary migration is used to enlarge grains by optimizing the annealing time, while vacancy clusters are induced through the aggregation of Ge vacancies during annealing. Such enlarged grains can weaken carrier scattering, while vacancy clusters can strengthen phonon scattering, leading to decoupled carrier-phonon scattering. As a result, a ratio between carrier mobility and lattice thermal conductivity of ∼492.8 cm3 V-1 s-1 W-1 K and a peak ZT of ∼0.4 at 473 K are achieved in Ge0.67Pb0.13Bi0.2Te. This work reveals the critical roles of enlarged grains and induced vacancy clusters in decoupling carrier-phonon scattering and demonstrates the viability of fabricating high-performance n-type GeTe materials via annealing optimization.
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Simultaneously Boosting Thermoelectric and Mechanical Properties of n-Type Mg 3Sb 1.5Bi 0.5-Based Zintls through Energy-Band and Defect Engineering. ACS NANO 2024; 18:1678-1689. [PMID: 38164927 DOI: 10.1021/acsnano.3c09926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Incorporating donor doping into Mg3Sb1.5Bi0.5 to achieve n-type conductivity is one of the crucial strategies for performance enhancement. In pursuit of higher thermoelectric performance, we herein report co-doping with Te and Y to optimize the thermoelectric properties of Mg3Sb1.5Bi0.5, achieving a peak ZT exceeding 1.7 at 703 K in Y0.01Mg3.19Sb1.5Bi0.47Te0.03. Guided by first-principles calculations for compositional design, we find that Te-doping shifts the Fermi level into the conduction band, resulting in n-type semiconductor behavior, while Y-doping further shifts the Fermi level into the conduction band and reduces the bandgap, leading to enhanced thermoelectric performance with a power factor as high as >20 μW cm-1 K-2. Additionally, through detailed micro/nanostructure characterizations, we discover that Te and Y co-doping induces dense crystal and lattice defects, including local lattice distortions and strains caused by point defects, and densely distributed grain boundaries between nanocrystalline domains. These defects efficiently scatter phonons of various wavelengths, resulting in a low thermal conductivity of 0.83 W m-1 K-1 and ultimately achieving a high ZT. Furthermore, the dense lattice defects induced by co-doping can further strengthen the mechanical performance, which is crucial for its service in devices. This work provides guidance for the composition and structure design of thermoelectric materials.
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An E-band multi-channel Doppler backscattering system on EAST. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:123507. [PMID: 38109469 DOI: 10.1063/5.0166949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 11/28/2023] [Indexed: 12/20/2023]
Abstract
An E-band (60-90 GHz) multi-channel Doppler backscattering (DBS) system with X-mode polarization has been installed on the Experimental Advanced Superconducting Tokamak (EAST), which can measure the turbulence at five different radial locations simultaneously. This system can launch 31 fixed microwave frequencies in the range of 60-90 GHz with a 1 GHz interval into the plasma, and five probing signals are selected by employing a reference signal and multiple filters. During experiments, the frequency of the reference signal is tunable in the E-band, and the selected probing signals can be changed as needed without any other adjustments, which can be performed in one shot or between shots. Furthermore, the incident angle can be adjusted from -10° to 20°, and the wavenumber range is 4-25 cm-1 with a wavenumber resolution of Δk/k ≤ 0.35. Ray tracing simulations are employed to calculate the scattering locations and the perpendicular wavenumber. In this article, the hardware design, ray tracing, and initial results obtained from the EAST plasma will be presented.
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Direct Current Treatment Tuning Crystallinity Leading to High-Performance p-Type Sb 2Te 3 Flexible Thin Films. ACS APPLIED MATERIALS & INTERFACES 2023; 15:37668-37674. [PMID: 37474529 DOI: 10.1021/acsami.3c06851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
With the development of wearable electronics, inorganic flexible thin films (f-TFs) with high thermoelectric performance have attracted increasing research interest. To further enhance the thermoelectric performance of p-type inorganic Sb2Te3-based f-TFs, we employed direct current treatment to tune the crystallinity by rationally tuning the direct current treatment time. Correspondingly, a high electrical conductivity of >845 S cm-1 and a moderate Seebeck coefficient of >110 μV K-1 within the entire measurement temperature range have been simultaneously achieved. Consequently, a high power factor of 12.84 μW cm-1 K-2 at 423 K has been realized in the as-prepared p-type Sb2Te3 f-TF treated by a direct current of 5 A for 4 min. A flexible thermoelectric device has been further assembled to demonstrate the power-generating capacity. This study indicates that the direct current treatment is an effective method to improve the thermoelectric performance of Sb2Te3 f-TFs.
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Development of a novel piezoelectric-driven non-resonant elliptical vibrator with adjustable characteristics. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:065008. [PMID: 37862519 DOI: 10.1063/5.0149361] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 06/04/2023] [Indexed: 10/22/2023]
Abstract
Aiming at the fabrication of a micro-textured surface, a novel piezoelectric-driven non-resonant elliptical vibrator is proposed in this paper; the output characteristics could be adjusted by the length change of the tool holder. The flexible mechanism is the primary structure of the vibrator, which includes a lever type mechanism, an enhanced Scott-Russell mechanism, and a T-shaped mechanism. The former two mechanisms are used to enlarge the output of the piezoelectric actuator, and the T-shaped mechanism is applied to transfer the parallel movements to the elliptical trajectory. The theoretical models including the elliptical trajectory, output stiffness, and resonant frequencies are established to investigate the impacts of the tool holder and controlling signals on the output characteristics of the vibrator, which are further validated using the finite element analysis method. A prototype is developed by integrating the non-resonant elliptical vibrator assembly and controlling system. Some experiments are carried out to verify the basic performance and the adjustable properties of the vibrator.
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Ultrarapid Nanomanufacturing of High-Quality Bimetallic Anode Library toward Stable Potassium-Ion Storage. Angew Chem Int Ed Engl 2023:e202303600. [PMID: 37041661 DOI: 10.1002/anie.202303600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/11/2023] [Accepted: 04/11/2023] [Indexed: 04/13/2023]
Abstract
Bimetallic alloy nanomaterials are promising anode materials for potassium-ion batteries (KIBs) due to their high electrochemical performance. The most well-adopted fabrication method for bimetallic alloy nanomaterials is tube furnace annealing (TFA) synthesis, which can hardly satisfy the trade-off among granularity, dispersity and grain coarsening due to mutual constraints. Herein, we report a facile, scalable and ultrafast high-temperature radiation (HTR) method for the fabrication of a library of ultrafine bimetallic alloys with narrow size distribution (~10-20 nm), uniform dispersion and high loading. The metal-anchor containing heteroatoms (i.e., O and N), ultrarapid heating/cooling rate (~103 K s-1) and super-short heating duration (several seconds) synergistically contribute to the successful synthesis of small-sized alloy anodes. As a proof-of-concept demonstration, the as-prepared BiSb-HTR anode shows ultrahigh stability indicated by negligible degradation after 800 cycles. The in situ X-ray diffraction reveals the K+ storage mechanism of BiSb-HTR. This study can shed light on the new, rapid and scalable nanomanufacturing of high-quality bimetallic alloys toward extended applications of energy storage, energy conversion and electrocatalysis.
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Retraction notice to “Two mixed-ligand coordination polymers: Magnetic properties and biological evaluation on myofascial pain syndrome by reducing IL-6 release” [J. Solid State Chem. 300 (2021) 122223]. J SOLID STATE CHEM 2023. [DOI: 10.1016/j.jssc.2023.123891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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[A case of acute cervical epidural infection caused by fishbone in pyriform fossa]. ZHONGHUA ER BI YAN HOU TOU JING WAI KE ZA ZHI = CHINESE JOURNAL OF OTORHINOLARYNGOLOGY HEAD AND NECK SURGERY 2023; 58:271-273. [PMID: 36878510 DOI: 10.3760/cma.j.cn115330-20220608-00338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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[Clinical and endoscopic characteristics of adult celiac disease]. ZHONGHUA NEI KE ZA ZHI 2023; 62:35-42. [PMID: 36631035 DOI: 10.3760/cma.j.cn112138-20220220-00130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Objective: The study aimed to analyze the clinical and endoscopic characteristics of adult celiac disease (CD) to provide a scientific basis for more effective CD diagnosis and treatment. Methods: In this cross-sectional study, the clinical and endoscopic data of 96 adult CD patients treated in the Department of Gastroenterology of the People's Hospital of Xinjiang Uygur Autonomous Region from March 2016 to December 2021 were retrospectively collected and analyzed. Results: A total of 96 CD patients were diagnosed, including 33 men and 63 women. The average age was 47±14 years (range, 18-81 years). The disease occurred mainly in the age group of 31-60 years. The median course of the disease was 2.0 (0.2-40.0) years. There were 41 (42.7%) classical and 55 (57.3%) non-classical CD patients. All patients with classical CD showed chronic diarrhea, often accompanied by abdominal pain (46.3%, 19/41), abdominal distension (17.1%, 7/41), anemia (65.9%, 27/41), and chronic fatigue (48.8%, 20/41). The main manifestations of non-classical CD were chronic abdominal pain (58.2%, 32/55), abdominal distension (32.7%, 18/55), anemia (40.0%, 22/55), and osteopenia/osteoporosis (38.2%, 21/55). Compared with non-classical CD, anemia developed more frequently in classical CD, and the difference was statistically significant (P = 0.012). The incidence of complications in CD patients was 36.5% (35/96), and the main complications were thyroid disease (19.8%, 19/96), connective tissue disease (6.2%, 6/96), and kidney disease (6.2%, 6/96). There was no significant difference between classical and non-classical CD (P>0.05). The frequency of endoscopic manifestations in CD patients was 84.4% (81/96). Duodenal bulb endoscopy showed nodular changes (72.9%, 70/96), grooved changes (10.4%, 10/96), and focal villous atrophy (9.4%, 9/96). The main manifestations of descending endoscopy were the decrease, flattening, or disappearance of duodenal folds (43.8%, 42/96), scallop-like changes (38.5%, 37/96), and nodular changes (34.4%, 33/96). Conclusions: Adult CD patients are mostly female. CD occurred mainly in the age group of 31-60 years. The clinical manifestations were mainly those of non-classical CD. Some patients often had other autoimmune diseases. Patients with characteristic endoscopic manifestations should be warned about the possibility of developing CD. Clinicians should strengthen the understanding of CD and reduce the related rates of missed diagnosis.
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Ultrafast Non-Equilibrium Synthesis of Cathode Materials for Li-Ion Batteries. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2208974. [PMID: 36401825 DOI: 10.1002/adma.202208974] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/13/2022] [Indexed: 06/16/2023]
Abstract
The synthesis of cathode materials plays an important role in determining the production efficiency, cost, and performance of lithium-ion batteries. However, conventional synthesis methods always experience a slow heating rate and involve a complicated multistep reaction process and sluggish reaction dynamics, leading to high energy and long time consumption. Herein, a high-temperature shock (HTS) strategy is reported for the ultrafast synthesis of cathode materials in seconds. The HTS process experiences an ultrahigh heating rate, leading to a non-equilibrium reaction and fast reaction kinetics, and avoids high energy and long time consumption. Mainstream cathode materials (such as LiMn2 O4 , LiCoO2 , LiFePO4 , and Li-rich layered oxide/NiO heterostructured material) are successfully synthesized with pure phases, oxygen vacancies, ultrasmall particle sizes, and good electrochemical performance. The HTS process not only provides an efficient synthesis approach for cathode materials, but also can be extended beyond lithium-ion batteries.
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[The risk of incident gastric cancer for populations with different precancerous gastric lesions: a prospective follow-up study]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2022; 43:1972-1978. [PMID: 36572472 DOI: 10.3760/cma.j.cn112338-20220817-00716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Objective: To provide evidence for optimizing the screening strategy for gastric cancer (GC), we evaluated the risk of incident GC for individuals with different precancerous gastric lesions in a prospective cohort study. Methods: Based on the National Upper Gastrointestinal Cancer Early Detection Program launched in Linqu, Shandong, a high-risk area of gastric cancer in China, we included a total of 14 087 subjects diagnosed with different gastric lesions stages by endoscopic screening from 2012 to 2018. Study subjects were prospectively followed up until December 31, 2019. The incidence of GC during the follow-up was ascertained by repeated endoscopic examinations, cancer, death registry reports, and active follow-up of study subjects and was confirmed by reviewing medical records extracted from the hospital information management system. The Poisson regression model was applied to calculate the relative risk (RR) and 95%CI for GC occurrence among subjects with different gastric lesions. Results: Among 14 087 subjects with different gastric lesions as determined by their first endoscopic examination in 2012-2018, 7 608 (54.00%) had a global diagnosis of superficial gastritis (SG), 2 848 (20.22%) had chronic atrophic gastritis (CAG), 3 103 (22.03%) had intestinal metaplasia (IM), and 520 (3.69%) had low-grade intestinal neoplasia (LGIN). During the follow-up, 109 subjects were diagnosed with GC, including 63 with high-grade intestinal neoplasia (HGIN) and 46 with invasive GC. Compared to subjects having normal gastric mucosa or SG, those with CAG (RR=3.85, 95%CI: 2.04-7.28), IM (RR=5.18, 95%CI: 2.79-9.60), and LGIN (RR=19.08, 95%CI: 9.97-36.53) had significantly increased risk of progression to GC. Individuals with these gastric lesions had an elevated risk of developing HGIN and invasive GC. For subjects with LGIN, the RR was 22.96 (95%CI: 9.71-54.27) for developing HGIN and 14.64 (95%CI: 5.37-39.93) for developing invasive GC. Subgroup analyses found that all age group subjects with LGIN diagnosed during the initial endoscopic examination had a significantly increased risk of developing the GC. Conclusions: Our large-scale prospective study on a high-risk area of GC showed that most residents aged 40-69 years had gastric lesions of different stages. Subjects with more advanced gastric lesions had a significantly increased risk of progression to GC.
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Engineering Atomic-to-Nano Scale Structural Homogeneity towards High Corrosion Resistance of Amorphous Magnesium-Based Alloys. MICROMACHINES 2022; 13:1992. [PMID: 36422421 PMCID: PMC9695775 DOI: 10.3390/mi13111992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/12/2022] [Accepted: 11/15/2022] [Indexed: 06/16/2023]
Abstract
Magnesium-based amorphous alloys have aroused broad interest in being applied in marine use due to their merits of lightweight and high strength. Yet, the poor corrosion resistance to chloride-containing seawater has hindered their practical applications. Herein, we propose a new strategy to improve the chloride corrosion resistance of amorphous Mg65Cu15Ag10Gd10 alloys by engineering atomic-to-nano scale structural homogeneity, which is implemented by heating the material to the critical temperature of the liquid-liquid transition. By using various electrochemical, microscopic, and spectroscopic characterization methods, we reveal that the liquid-liquid transition can rearrange the local structural units in the amorphous structure, slightly decreasing the alloy structure's homogeneity, accelerate the formation of protective passivation film, and, therefore, increase the corrosion resistance. Our study has demonstrated the strong coupling between an amorphous structure and corrosion behavior, which is available for optimizing corrosion-resistant alloys.
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Stress‐Regulation Design of Mesoporous Carbon Spheres Anodes with Radial Pore Channels Toward Ultrastable Potassium‐Ion Batteries. SMALL SCIENCE 2022. [DOI: 10.1002/smsc.202200045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Post-Electric Current Treatment Approaching High-Performance Flexible n-Type Bi 2Te 3 Thin Films. MICROMACHINES 2022; 13:1544. [PMID: 36144166 PMCID: PMC9505272 DOI: 10.3390/mi13091544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/12/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
Inorganic n-type Bi2Te3 flexible thin film, as a promising near-room temperature thermoelectric material, has attracted extensive research interest and application potentials. In this work, to further improve the thermoelectric performance of flexible Bi2Te3 thin films, a post-electric current treatment is employed. It is found that increasing the electric current leads to increased carrier concentration and electric conductivity from 1874 S cm−1 to 2240 S cm−1. Consequently, a high power factor of ~10.70 μW cm−1 K−2 at room temperature can be achieved in the Bi2Te3 flexible thin films treated by the electric current of 0.5 A, which is competitive among flexible n-type Bi2Te3 thin films. Besides, the small change of relative resistance <10% before and after bending test demonstrates excellent bending resistance of as-prepared flexible Bi2Te3 films. A flexible device composed of 4 n-type legs generates an open circuit voltage of ~7.96 mV and an output power of 24.78 nW at a temperature difference of ~35 K. Our study indicates that post-electric current treatment is an effective method in boosting the electrical performance of flexible Bi2Te3 thin films.
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[Application of ROC and PR curves in the evaluation of clinical diagnostic testing]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2022; 56:1341-1347. [PMID: 36207901 DOI: 10.3760/cma.j.cn112150-20220104-00007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
This study reviewed the concepts and properties of the receiver operating characteristic (ROC) curve and precision recall (PR) curve, and made suggestions on the application of two curves based on the prevalence in combination with the results of simulation data. This study demonstrated that the ROC curve and PR curve had different properties, which could reflect the performance of diagnostic methods from various aspects. These two curves should be selected with a consideration of prevalence and clinical scenarios. When the prevalence was less than 20%, especially less than 5%, the PR curve could be adopted.
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[A case report of acute methyl acetate poisoning in cloth processing workshop]. ZHONGHUA LAO DONG WEI SHENG ZHI YE BING ZA ZHI = ZHONGHUA LAODONG WEISHENG ZHIYEBING ZAZHI = CHINESE JOURNAL OF INDUSTRIAL HYGIENE AND OCCUPATIONAL DISEASES 2022; 40:447-449. [PMID: 35785901 DOI: 10.3760/cma.j.cn121094-20210406-00191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This article analyzed the clinical data of a patient with occupational chemical poisoning in a fabric processing workshop in August 2020, and carried out occupational hygiene investigation and testing. The patient went to the doctor because of painless progressive vision loss in both eyes, and was clinically diagnosed with methanol poisoning optic neuropathy in both eyes. The glue, solvent, washing machine water, and curing agent used in the workshop were used for qualitative analysis of volatile organic components, and methyl acetate was all detected. Esters, the relative percentages were 42.56%, 66.67%, 46.43%, and 41.63%, respectively. Therefore, it was judged that the patient was occupational acute methyl acetate poisoning, the enterprise should strengthen the awareness of safe production and enhance the occupational hygiene knowledge and self-protection awareness of workers.
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Ultrafast Porous Carbon Activation Promises High-Energy Density Supercapacitors. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2200954. [PMID: 35557492 DOI: 10.1002/smll.202200954] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 04/19/2022] [Indexed: 06/15/2023]
Abstract
Activated porous carbons (APCs) are traditionally produced by heat treatment and KOH activation, where the production time can be as long as 2 h, and the produced activated porous carbons suffer from relatively low specific surface area and porosity. In this study, the fast high-temperature shock (HTS) carbonization and HTS-KOH activation method to synthesize activated porous carbons with high specific surface area of ≈843 m2 g-1 , is proposed. During the HTS process, the instant Joule heating (at a heating speed of ≈1100 K s-1 ) with high temperature and rapid quenching can effectively produce abundant pores with homogeneous size-distribution due to the instant melt of KOH into small droplets, which facilitates the interaction between carbon and KOH to form controllable, dense, and small pores. The as-prepared HTS-APC-based supercapacitors deliver a high energy density of 25 Wh kg-1 at a power density of 582 W kg-1 in the EMIMBF4 ionic liquid. It is believed that the proposed HTS technique has created a new pathway for manufacturing activated porous carbons with largely enhanced energy density of supercapacitors, which can inspire the development of energy storage materials.
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Cheap, Large-Scale, and High-Performance Graphite-Based Flexible Thermoelectric Materials and Devices with Supernormal Industry Feasibility. ACS APPLIED MATERIALS & INTERFACES 2022; 14:8066-8075. [PMID: 35129964 DOI: 10.1021/acsami.1c24649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Flexible thermoelectric materials and devices show great potential to solve the energy crisis but still face great challenges of high cost, complex fabrication, and tedious postprocessing. Searching for abnormal thermoelectric materials with rapid and scale-up production can significantly accelerate their applications. Here, we develop superlarge 25 × 20 cm2 commercial graphite-produced composite films in batches, achieved by a standard 10 min industrial process. The high cost effectiveness (S2σ/cost) of 7250 μW g m-1 K-2 $-1 is absolutely ahead of that of the existing thermoelectric materials. The optimized composite film shows a high power factor of 94 μW m-1 K-2 at 150 °C, representing the optimal value of normal carbon materials so far. Furthermore, we design two types of flexible thermoelectric devices fabricated based on such a novel composite, which achieve an output open-circuit voltage of 3.70 mV using the human wrist as the heat source and 1.33 mV soaking in river water as the cold source. Our study provides distinguished inspiration to enrich flexible and cost-effective thermoelectric materials with industrial production.
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Impurity Removal Leading to High-Performance CoSb 3-Based Skutterudites with Synergistic Carrier Concentration Optimization and Thermal Conductivity Reduction. ACS APPLIED MATERIALS & INTERFACES 2021; 13:54185-54193. [PMID: 34735110 DOI: 10.1021/acsami.1c16622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Thermoelectric properties of CoSb3-based skutterudites are greatly determined by the removal of detrimental impurities, such as (Fe/Co)Sb2, (Fe/Co)Sb, and Sb. In this study, we use a facile temperature gradient zone melting (TGZM) method to synthesize high-performance CoSb3-based skutterudites by impurity removal. After removing metallic or semimetallic impurities (Fe/Co)Sb, (Fe/Co)Sb2, and Sb, the carrier concentration of TGZM-Ce0.75Fe3CoSb12 can be reduced to 1.21 × 1020 cm-3 and the electronic thermal conductivity dramatically reduced to 0.7 W m-1 K-1 at 693 K. Additionally, removing these impurities also effectively reduces the lattice thermal conductivity from 7.2 W m-1 K-1 of cast-Ce0.75Fe3CoSb12 to 1.02 W m-1 K-1 of TGZM-Ce0.75Fe3CoSb12 at 693 K. As a consequence, TGZM-Ce0.75Fe3CoSb12 approaches a high power factor of 11.7 μW cm-1 K-2 and low thermal conductivity of 1.72 W m-1 K-1 at 693 K, leading to a peak zT of 0.48 at 693 K, which is 10 times higher than that of cast-Ce0.75Fe3CoSb12. This study indicates that our facile TGZM method can effectively synthesize high-performance CoSb3-based skutterudites by impurity removal and set up a solid foundation for further development.
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Ce Filling Limit and Its Influence on Thermoelectric Performance of Fe 3CoSb 12-Based Skutterudite Grown by a Temperature Gradient Zone Melting Method. MATERIALS (BASEL, SWITZERLAND) 2021; 14:6810. [PMID: 34832212 PMCID: PMC8620759 DOI: 10.3390/ma14226810] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 11/05/2021] [Accepted: 11/09/2021] [Indexed: 11/21/2022]
Abstract
CoSb3-based skutterudite is a promising mid-temperature thermoelectric material. However, the high lattice thermal conductivity limits its further application. Filling is one of the most effective methods to reduce the lattice thermal conductivity. In this study, we investigate the Ce filling limit and its influence on thermoelectric properties of p-type Fe3CoSb12-based skutterudites grown by a temperature gradient zone melting (TGZM) method. Crystal structure and composition characterization suggests that a maximum filling fraction of Ce reaches 0.73 in a composition of Ce0.73Fe2.73Co1.18Sb12 prepared by the TGZM method. The Ce filling reduces the carrier concentration to 1.03 × 1020 cm-3 in the Ce1.25Fe3CoSb12, leading to an increased Seebeck coefficient. Density functional theory (DFT) calculation indicates that the Ce-filling introduces an impurity level near the Fermi level. Moreover, the rattling effect of the Ce fillers strengthens the short-wavelength phonon scattering and reduces the lattice thermal conductivity to 0.91 W m-1 K-1. These effects induce a maximum Seebeck coefficient of 168 μV K-1 and a lowest κ of 1.52 W m-1 K-1 at 693 K in the Ce1.25Fe3CoSb12, leading to a peak zT value of 0.65, which is 9 times higher than that of the unfilled Fe3CoSb12.
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Two mixed-ligand coordination polymers: Magnetic properties and biological evaluation on myofascial pain syndrome by reducing IL-6 release. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2021.122223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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The cross-polarization scattering system for the magnetic fluctuation measurement in the Experimental Advanced Superconducting Tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:043511. [PMID: 34243396 DOI: 10.1063/5.0012520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 03/16/2021] [Indexed: 06/13/2023]
Abstract
The cross-polarization scattering (CPS) system for magnetic fluctuation measurements in the Experimental Advanced Superconducting Tokamak (EAST) has been designed and installed. Different from the Doppler reflectometer (DR) system, the CPS system detects the perpendicular polarization of the electromagnetic wave induced by magnetic fluctuations B̃. The CPS system in the EAST has been developed from the existing Doppler reflectometer system, and they are integrated together for simultaneous measurement of magnetic and density fluctuations. Ray-tracing simulations are used to calculate the scattering locations and the wavenumber coverage of the magnetic fluctuation for CPS. In the experiments, the CPS and DR system data were different in Doppler shift, amplitude, and spectrum broadening. In this article, the hardware design, the ray tracing, and the preliminary results of the system in the EAST are presented.
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Hierarchical Structures Advance Thermoelectric Properties of Porous n-type β-Ag 2Se. ACS APPLIED MATERIALS & INTERFACES 2020; 12:51523-51529. [PMID: 33147960 DOI: 10.1021/acsami.0c15341] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Owing to the intrinsically good near-room-temperature thermoelectric performance, β-Ag2Se has been considered as a promising alternative to n-type Bi2Te3 thermoelectric materials. Herein, we develop an energy- and time-efficient wet mechanical alloying and spark plasma sintering method to prepare porous β-Ag2Se with hierarchical structures including high-density pores, a metastable phase, nanosized grains, semi-coherent grain boundaries, high-density dislocations, and localized strains, leading to an ultralow lattice thermal conductivity of ∼0.35 W m-1 K-1 at 300 K. A relatively high carrier mobility is obtained by adjusting the sintering temperature to obtain pores with an average size of ∼260 nm, therefore resulting in a figure of merit, zT, of ∼0.7 at 300 K and ∼0.9 at 390 K. The single parabolic band model predicts that zT of such porous β-Ag2Se can reach ∼1.1 at 300 K if the carrier concentration can be tuned to ∼1 × 1018 cm-3, suggesting that β-Ag2Se can be a competitive candidate for room-temperature thermoelectric applications.
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[Determination of trichlorobenzene in workplace air by solvent desorption gas chromatography]. ZHONGHUA LAO DONG WEI SHENG ZHI YE BING ZA ZHI = ZHONGHUA LAODONG WEISHENG ZHIYEBING ZAZHI = CHINESE JOURNAL OF INDUSTRIAL HYGIENE AND OCCUPATIONAL DISEASES 2020; 38:538-541. [PMID: 32746580 DOI: 10.3760/cma.j.cn121094-20190917-00379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To develop a solvent desorption-gas chromatography method for determination of trichlorobenzene in workplace air. Methods: Trichlorobenzene in workplace air were captured by Sampling tube consisting of glass fiber filter and solvent desorption activated carbon and desorbed with carbon disulfide, separated through capillary chromatographic column, and then analyzed by gas chromatography-electron capture detector. Results: The linear ranges of 1, 2, 3-trichlorobenzene, 1, 2, 4-trichlorobenzene and 1, 3, 5-trichlorobenzene were 12.20-1220.00, 16.60-1660.00 and 14.80-1480.00 μg/L, respectively, and the related coefficients were between 0.99946 to 0.99948. The relative standard deviations (RSD) within the groups of 1, 2, 3-trichlorobenzene, 1, 2, 4-trichlorobenzene and 1, 3, 5-trichlorobenzene were 1.96%-2.68%, 1.73%-2.82% and 1.81%-2.56%, respectively, and the RSD between the groups were 3.27%-4.25%, 2.85%-4.83% and 3.46%-4.43%, respectively. The average recovery efficiencies were 92.4%, 92.0% and 93.6%, respectively. The minimum quantification concentrations were 0.81, 1.53 and 1.18 μg/m(3), respectively (3 ml desorption solution, 15.00 L sample) . The samples could be stored at room temperature for at least 5 days. Conclusion: This method could be used for monitoring of 1, 2, 3-trichlorobenzene, 1, 2, 4-trichlorobenzene and 1, 3, 5-trichlorobenzene in workplace air.
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[Risk factors of permanent stoma in rectal cancer patients undergoing transabdominal anterior resection with temporary stoma]. ZHONGHUA WEI CHANG WAI KE ZA ZHI = CHINESE JOURNAL OF GASTROINTESTINAL SURGERY 2020; 23:780-785. [PMID: 32810950 DOI: 10.3760/cma.j.cn.441530-20191107-00475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the risk factors of turning temporary stoma into permanent stoma in rectal cancer patients undergoing transabdominal anterior resection with temporary stoma. Methods: A case-control study was carried out. Data of rectal cancer patients who underwent transabdominal anterior resection with temporary stoma and completed follow-up in Department of General Surgery of Xiangya Hospital of Central South University from June 2008 to June 2018 were collected and analyzed. In this study, temporary stoma included defunctioning stoma (ostomy was made during operation) and salvage stoma (ostomy was made within one month after operation due to anastomotic leakage or severe complications). Cases of multiple intestinal tumors were excluded. A total of 308 rectal cancer patients were enrolled in the study, including 198 males and 110 females with a median age of 56 (48-65) years. Ninety-four patients received intraperitoneal chemotherapy during operation. Among 308 patients, upper rectal cancer was observed in 64 cases, middle rectal cancer in 89 cases and low rectal cancer in 155 cases. Twenty patients underwent transverse colostomy and 288 underwent ileostomy. Phone call following-up was conducted from August to September 2019 to investigate whether stoma was reversed, causes of reversal failure, and tumor relapsed or not in detail. Permanent stoma was defined as that the stoma was still not reversed by the latest follow-up. The univariate analysis was performed with chi-square test or Fisher's exact test, and variables with P value < 0.10 were included in the non-conditional logistic regression model for multivariate analysis. Results: The median follow-up time was 54.3 (32.4-73.8) months. During follow-up, 8 cases had local recurrence and 37 cases had distant metastasis. Among the 308 patients with temporary ostomy, 247 (80.2%) patients had stomas reversed and the median interval time was 4.5 (3.5-6.1) months. The median interval time in 65 patients with salvage stoma was significantly longer that in 182 patients with defunctioning stoma [5.5 (4.3-7.5) vs. 4.2 (3.4-5.5) months; Z=-4.387, P<0.001]. The temporary ostomy was confirmed to become permanent stoma in 61 patients (19.8%), including 45 cases of defunctioning stoma and 16 cases of salvage stoma. Univariate analysis showed that preoperative anemia, intraperitoneal chemotherapy during operation, middle rectal cancer, transverse colostomy, pathological stage, postoperative local recurrence and distant metastasis were associated with permanent stoma (all P<0.10). Multivariate analysis revealed that the intraperitoneal chemotherapy during operation (OR=1.961, 95% CI: 1.029-3.738, P=0.041), middle rectal cancer (OR=2.401, 95% CI: 1.195-4.826, P=0.014), transverse colostomy (OR=3.433, 95% CI: 1.234-9.553, P=0.018), and distant metastasis (OR=8.282, 95% CI:3.820-17.954, P<0.001) were independent risk factors of permanent stoma. Conclusions: There is high risk of turning temporary stoma into permanent stoma among rectal cancer patients undergoing transabdominal anterior resection who receive intraperitoneal chemotherapy during operation, present as the middle rectal cancer, undergo transverse colostomy or develop distant metastasis. Surgeons need to evaluate and balance the risks and benefits thoroughly, and then inform the patients in order to avoid potential conflicts.
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[Retrospective analysis of mechanical thrombectomy for distal branch occlusion of middle cerebral artery]. ZHONGHUA YI XUE ZA ZHI 2020; 100:1240-1244. [PMID: 32344496 DOI: 10.3760/cma.j.cn112137-20191120-02531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the necessity, feasibility, technical points, operative complications and prognosis of mechanical thrombectomy for distal branch occlusion of middle cerebral artery. Methods: Mechanical thrombectomy was performed on 42patients (28 males,14 females; age ranged from 43 to 88 years, mean 65.48years)with distal branch occlusion of middle cerebral artery (M2, M3), between May 2017 to July 2019. Theclinical feature was retrospectively analyzed. The NIHSS score before operation, 24 hours after operation and 1 week after operation, the recanalization of occluded vessels during operation, the complications and the recovery after 3 months (3 months mRS score) were analyzed. Results: Of the 42 patients, 38 patients were successfully recanalized, and the recanalization rate was 90.48%. Postoperative hemorrhage in 6 cases and vasospasm in 17 cases. At 90 days after operation, the mRS score was 0 in 13 cases, 1 in 11 cases, 2 in 6 cases, and 0 cases died. Conclusions: Mechanical thrombotomy is safe and feasible for patients with distal branch occlusion of middle cerebral artery (M2, M3). However, the risks and benefits of patients should be fully considered.
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Flexible Carbon-Fiber/Semimetal Bi Nanosheet Arrays as Separable and Recyclable Plasmonic Photocatalysts and Photoelectrocatalysts. ACS APPLIED MATERIALS & INTERFACES 2020; 12:24845-24854. [PMID: 32374583 DOI: 10.1021/acsami.0c05695] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this work, we prepared flexible carbon-fiber/semimetal Bi nanosheet arrays from solvothermal-synthesized carbon-fiber/Bi2O2CO3 nanosheet arrays via a reductive calcination process. The flexible carbon-fiber/semimetal Bi nanosheet arrays can function as photocatalysts and photoelectrocatalysts for 2,4-dinitorphenol oxidation. Compared with carbon-fiber/Bi2O2CO3 nanosheet arrays, the newly designed flexible carbon-fiber/semimetal Bi nanosheet arrays show enhanced ultraviolet-visible (UV-vis) light absorption efficiency and photocurrent, photocatalytic, and photoelectrocatalytic activities. Photocatalytic analyses indicate that the surface plasmon resonance (SPR) of semimetal Bi occurs under solar-simulated light irradiation during the photocatalytic process. The carbon-fiber traps the hot electrons exerted from the SPR of semimetal Bi and creates holes in the semimetal Bi nanosheets, which boosts the photocatalytic activity of the carbon fiber through plasmonic sensitization. Both photocatalytic experiments and density functional theory (DFT) calculations indicate that the electrons transferred to the carbon fiber and the holes created in semimetal Bi contribute to the formation of •O2- and •OH, respectively. The synergistic effect between electrocatalysis and photocatalysis under the solar-simulated light results in almost complete degradation of 2,4-dinitorphenol during the photoelectrocatalytic process. This work realizes a non-noble-metal plasmonic catalyst and provides a new avenue for the commercialization of photocatalysis and photoelectrocatalysis using the separable and recyclable carbon-fiber/semimetal Bi nanosheet arrays in the environment-related field.
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Promising and Eco-Friendly Cu 2 X-Based Thermoelectric Materials: Progress and Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1905703. [PMID: 31944453 DOI: 10.1002/adma.201905703] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/18/2019] [Indexed: 06/10/2023]
Abstract
Due to the nature of their liquid-like behavior and high dimensionless figure of merit, Cu2 X (X = Te, Se, and S)-based thermoelectric materials have attracted extensive attention. The superionicity and Cu disorder at the high temperature can dramatically affect the electronic structure of Cu2 X and in turn result in temperature-dependent carrier-transport properties. Here, the effective strategies in enhancing the thermoelectric performance of Cu2 X-based thermoelectric materials are summarized, in which the proper optimization of carrier concentration and minimization of the lattice thermal conductivity are the main focus. Then, the stabilities, mechanical properties, and module assembly of Cu2 X-based thermoelectric materials are investigated. Finally, the future directions for further improving the energy conversion efficiency of Cu2 X-based thermoelectric materials are highlighted.
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[Interpretation of clinical practice guideline for anorectal day surgery 2019 edition]. ZHONGHUA WEI CHANG WAI KE ZA ZHI = CHINESE JOURNAL OF GASTROINTESTINAL SURGERY 2019; 22:1118-1123. [PMID: 31874526 DOI: 10.3760/cma.j.issn.1671-0274.2019.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
As the rapid development of minimally invasive techniques, anesthesia, and enhanced recovery after surgery (ERAS), anorectal day surgery receiving more and more attention by improving efficiency of medical care while reducing cost and hospitalized infection. However, day surgery also faces the challenge of completing the whole process from patient admission to discharge within 24 hours. Therefore, establishing a reasonable and detailed day surgery process is the cornerstone to guarantee safe medical practice and patients satisfaction. National Clinical Research Center for Geriatric Disorders (Xiangya), together with China Ambulatory Surgery Alliance formulates the clinical practice guideline for anorectal day surgery 2019 edition. Here we make some interpretations of the guidelines on the detailed process of anorectal day surgery, including indication, preoperative examination, preoperative risk evaluation, health education, assessment of day surgery anesthesia and before leaving postanesthesia care unit (PACU), postoperative management, assessment of discharge and follow-up, for the convenience of various medical centers.
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[Association between circular RNAs expression in serum and gastric cancer]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2019; 40:1527-1532. [PMID: 32062910 DOI: 10.3760/cma.j.issn.0254-6450.2019.12.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To analyze the association between circular RNAs expression in serum and gastric cancer and evaluate the potential of the related markers in early diagnosis of gastric cancer. Methods: Forty eight gastric cancer cases in Linqu County People's Hospital were selected as case group, and 48 controls matched by age and sex were randomly selected in the gastric cancer screening cohort during the same period. The expression levels of hsa_circ_002059, hsa_circ_0000096 and hsa_circ_0001895 were detected by quantitative real-time PCR. The results were compared between case group and control group. Results: The positive expression rates of hsa_circ_002059, hsa_circ_0000096 and hsa_circ_0001895 were 70.8%, 47.9%, 75.0% in case group, slightly higher than those in control group (58.3%, 31.3%, 60.4%), although P values were all more than 0.05. The expression level medians of the 3 candidate circRNAs expression levels were 1.60% (0-5.64%), 0 (0-0.61%), 0.91% (0.06%-1.88%) in case group, while 0.05% (0-6.07%), 0 (0-0.34%), 0.42% (0-1.39%) in control group, respectively. Conditional logistic regression analysis showed that the association strength of high expressions of 3 candidate circRNAs with gastric cancer showed an increase trend, but the differences had no significance after adjusted by Helicobacter pylori infection, smoking and drinking status (all P>0.05). Further analysis by combining the 3 candidate circRNAs showed the increased strength of association between circRNAs and gastric cancer with the elevated number of positive circRNAs in serum (trend test P=0.040) compared with circRNAs negative persons. Conclusion: Our study preliminarily suggested that the expression of hsa_circ_002059, hsa_circ_0000096 and hsa_circ_0001895 in serum might be correlated with gastric cancer.
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[Spatial-temporal characteristics of other infectious diarrhea in Jiangsu province, 2010-2017]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2019; 40:1269-1273. [PMID: 31658529 DOI: 10.3760/cma.j.issn.0254-6450.2019.10.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To analyze the spatial-temporal characteristics of other infectious diarrhea (OID) in Jiangsu province from 2010 to 2017, and to provide evidence for setting up prevention and control programs of the disease. Methods: Data was from the Chinese Center for Disease Control and Prevention and the Statistics Bureau of Jiangsu province. Descriptive methods were used to illustrate the epidemiological characteristics of OID from 2010 to 2017. Global autocorrelation statistics method (Moran's I) was used to detect the spatial autocorrelation of OID, annually. Kulldorff M spatiotemporal scan statistics was used to analyze the spatial-temporal clustering of OID. ArcGIS 10.0 software, SaTScan 9.4 software and Excel 2017 software were also applied. Results: A total of 126 341 OID cases were found in Jiangsu province from 2010 to 2017 with an average annual incidence as 19.96/100 000. Children under five accounted for 55.08% (69 590/126 341) of the total cases. Obvious seasonal backshift with the increasing trends of the OID was noticed. There appeared four areas with high incidence of OID in the whole province, including Wuxi, Suzhou, Yancheng and Xuzhou. OID showed positive spatial autocorrelation at the county level with higher Moran's I from 0.19 to 0.33 (P<0.01). There appeared four positive clusters, all occurred in the high incidence period of OID, including the cluster area from the intersection areas of Changzhou and Wuxi (RR=7.61, LLR=2 605.80, P<0.01), respectively. Conclusion: With the increasing trends and the seasonal backshift of OID cases, pathogen surveillance programs set for those scattered children under five, in clustered regions and epidemic seasons should be strengthened.
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High Porosity in Nanostructured n-Type Bi 2Te 3 Obtaining Ultralow Lattice Thermal Conductivity. ACS APPLIED MATERIALS & INTERFACES 2019; 11:31237-31244. [PMID: 31397997 DOI: 10.1021/acsami.9b12079] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Porous structure possesses full potentials to develop high-performance thermoelectric materials with low lattice thermal conductivity. In this study, the n-type porous nanostructured Bi2Te3 pellet is fabricated by sintering Bi2Te3 nanoplates synthesized with a facile solvothermal method. With adequate sublimations of Bi2TeO5 during the spark plasma sintering, homogeneously distributed pores and dense grain boundaries are successfully introduced into the Bi2Te3 matrix, causing strong phonon scatterings, from which an ultralow lattice thermal conductivity of <0.1 W m-1 K-1 is achieved in the porous nanostructured Bi2Te3 pellet. With the well-maintained decent electrical performance, a power factor of 10.57 μW cm-1 K-2 at 420 K, as well as the reduced lattice thermal conductivity, secured a promising zT value of 0.97 at 420 K, which is among the highest values reported for pure n-type Bi2Te3. This study provides the insight of realizing ultralow lattice thermal conductivity by synergistic phonon scatterings of pores and nanostructure in the n-type Bi2Te3-based thermoelectric materials.
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[A comparative study of intrahepatic cholangiocarcinoma and hepatocellular carcinoma with reference to clinical features and prognosis]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2019; 27:511-515. [PMID: 31357776 DOI: 10.3760/cma.j.issn.1007-3418.2019.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To comparatively study intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC) with reference to clinical features and prognosis in Chinese Han population. Methods: 699 cases of HCC and 170 cases of ICC confirmed by surgical pathological files from 2009 to 2010 were included and followed-up. The differences in demographic characteristics, hepatitis B virus infection, clinical characteristics, biochemical indexes, tumor markers and prognosis of HCC and ICC were analyzed retrospectively by means of paired t-test, analysis of variance, chi-square test and Pearson's correlation coefficient. Results: Among 869 cases of primary liver cancer, HCC and ICC accounted for 80.43% and 19.57%. The old aged (P < 0.001) male incidence of HCC was higher than that of ICC (P < 0.001). The infection rates of hepatitis B virus were 89.84% and 35.88% in HCC and ICC, respectively, and the infection rates of hepatitis B, serum HBsAg postive rate and DNA account in HCC were higher than ICC (P < 0.001). The incidence of liver cirrhosis and hepatic schistosomiasis in HCC was also significantly different from that in ICC (both P < 0.01). Pearson's correlation analysis showed that there was a significant negative correlation between HCC or ICC tumor type and hepatic schistosomiasis (r = -0.018, P < 0.001), and there was a significant positive correlation between HCC and hepatic cirrhosis (r = 0.179, P < 0.001, and r = 0.528, P < 0.001, respectively). However, the proportion of cirrhosis and schistosomiasis in hepatitis B positive ICC cases was not significantly different from that in HCC cases (P > 0.05). Among the biochemical indicators, there were significant differences between HCC and ICC in the abnormal rate of ALT(P < 0.01), AST(P < 0.05), ALP (P < 0.01), GGT (P < 0.01) and TBIL (P < 0.01) while there was no significant difference between ALB and pre-ALB (P > 0.05) in HCC and ICC groups. The content and abnormal rate of alpha-fetoprotein were higher in HCC (P < 0.01), while the content and abnormal rate of carcinoembryonic antigen and carbohydrate antigen 19-9 were higher in ICC (P < 0.01). The 10-year survival rate and median survival time (46.92% and 80.3 months) of HCC were higher than those of ICC (12.57% and 12.4 months) (P < 0.01). Conclusion: In the study population, compared with ICC cases, the old aged male HCC cases are more common and has higher infection rate of hepatitis B virus and cirrhosis, but liver schistosomiasis is less common. The inflammatory damage, secretion and metabolic function of HCC were different from that of ICC cases, while the synthetic reserve function was similar to that of ICC and the prognosis of HCC cases was significantly better. The incidence of cirrhosis and schistosomiasis in ICC cases with positive hepatitis B virus infection was not significantly different from that of HCC cases.
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[Factors influencing poor prognosis of mechanical thrombectomy in time window of acute ischemic stroke]. ZHONGHUA YI XUE ZA ZHI 2019; 99:1976-1980. [PMID: 31269604 DOI: 10.3760/cma.j.issn.0376-2491.2019.25.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: Investigate the causes of poor prognosis of mechanical thrombectomy in the time window of acute ischemic stroke (AIS) with anterior circulation. Methods: A retrospective analysis was made on the data of 78 patients with anterior circulation AIS who underwent mechanical thrombectomy in the time window from January 2017 to December 2017 in the Department of Vascular Neurosurgery of Liaocheng Brain Hospital. The modified Rankin scale (mRS) was used to evaluate the prognosis of the patients 3 months after operation. According to the prognosis,the patients were divided into the group with good prognosis (42 cases, mRS<2 points) and the group with poor prognosis (36 cases, mRS<3 points). Univariate and multivariate Logistic regression analysis was used to analyze the related factors of poor prognosis. Results: (1) Univariate analysis showed that the prognosis of patients with good combination and primary stenosis of diabetes mellitus and atherosclerosis was lower than that of patients with poor prognosis (P<0.05). The collateral circulation compensation rate and vascular recanalization rate of patients with good prognosis were higher than those of patients with poor prognosis (P<0.05). Learning significance (P<0.05). (2) Multivariate analysis showed that diabetes mellitus (P=0.035), collateral circulation compensation (P=0.011) and primary atherosclerotic stenosis (P=0.042) were independent risk factors for poor prognosis. Conclusion: Perfect preoperative evaluation and strict screening of patients, good collateral circulation compensation,individualized treatment for patients with primary atherosclerotic stenosis,and strict control of postoperative hyperglycemia can improve the clinical prognosis of endovascular therapy.
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Carbon-Encapsulated Copper Sulfide Leading to Enhanced Thermoelectric Properties. ACS APPLIED MATERIALS & INTERFACES 2019; 11:22457-22463. [PMID: 31194506 DOI: 10.1021/acsami.9b06212] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Copper sulfide has been regarded as a promising thermoelectric material with relatively high thermoelectric performance and abundant resource. Large-scale synthesis and low-cost production of high-performance thermoelectric materials are keys to widespread application of thermoelectric technology. Here, Cu2- xS particles encapsulated in a thin carbon shell are fabricated by a scalable wet chemical method (19.7 g/batch). The synthesized particles go through the crystal-phase transition from orthorhombic to tetragonal during high-temperature annealing and sintering. After the phase transition, electrical conductivity of this composite (Cu2- xS@C) increases by approximately 50% compared to that of the pure Cu2- xS sample, and can be attibuted to an increase in carrier concentration. Phonon scattering interface formation and superionic phase of Cu2- xS@C results in very low lattice thermal conductivity of 0.22 W m-1 K-1, and maximum thermoelectric figure of merit ( ZT) of 1.04 at 773 K, which is excellent for thermoelectric performance in pure-phase copper sulfide produced via chemical synthesis. This discovery sets the stage for the use of facile wet chemical synthesis methods for large-scale transition-metal chalcogenide thermoelectric material production.
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[The progress of research on the immune pathogenesis and biomarkers in optic neuritis related to neuromyelitis optica]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2019; 55:228-233. [PMID: 30841690 DOI: 10.3760/cma.j.issn.0412-4081.2019.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The idiopathic optic neuritis (ION) which is related to neuromyelitis optica (NMO) and neuromyelitis optica spectrum disorders (NMOSD) is called optic neuritis related to neuromyelitis optica (NMO-ON). Because of the high rates of blindness, disability and fatality of NMO, the heterogeneous clinical presentation, severity of neurologic disability following relapses, and variability of therapeutic responses, reliable and sensitive biomarkers for onset, relapse, and progression in NMO are urgently needed. Currently, detecting aquaporin-4 (AQP4) antibodies (AQP4-IgG or NMO-IgG) in serum is employed as the major supporting approach for the diagnosis of seropositive NMO, however, AQP4-IgG seronegativity in 10% to 25% of NMO patients suggests that there are several other factors involved in NMO immunopathogenesis. Collaborative international studies hold great promise for establishing and validating biomarkers of NMO. This article discusses known and potential biomarkers for NMO. The biomarkers of NMO maybe the potential biomarkers of NMO-ON, for ION is the initial presentation and the earliest stage. (Chin J Ophthalmol, 2019, 55:228-233).
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Five-channel tunable W-band Doppler backscattering system in the experimental advanced superconducting tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:024704. [PMID: 30831725 DOI: 10.1063/1.5075615] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/18/2019] [Indexed: 06/09/2023]
Abstract
A 5-channel Doppler backscattering system has been designed and installed in the Experimental Advanced Superconducting Tokamak (EAST). Through an I/Q-type double sideband modulator and a frequency multiplier, an array of finely spaced (Δf = 400 MHz) frequencies that span 1.6 GHz has been created. The center of the array bandwidth is tunable within the range of 75-97.8 GHz, which covers most of the W band (75-110 GHz). The incident angle can be adjusted from -4° to 12°, and the wavenumber range is 4-15 cm-1 with a wavenumber resolution of Δk/k ≤ 0.35. Ray tracing is used to calculate the scattering location and the scattering wavenumber. This article details the hardware design, the ray tracing, and the preliminary experimental results from EAST plasmas.
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High Thermoelectric Performance in Sintered Octahedron-Shaped Sn(CdIn) xTe 1+2 x Microcrystals. ACS APPLIED MATERIALS & INTERFACES 2018; 10:38944-38952. [PMID: 30335928 DOI: 10.1021/acsami.8b14233] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this study, we fabricate In/Cd codoped octahedron-shape Sn(CdIn) xTe1+2 x microcrystals with a promising thermoelectric performance by using a facile solvothermal method. The high hole-carrier concentration of pristine SnTe is significantly reduced through effective In/Cd codoping, which increases the Seebeck coefficient in a wide temperature range. Moreover, codoped In/Cd not only modifies the band structure by creating the resonance energy level at the valence band and converging light hole and heavy hole valence bands of SnTe but also provides In/Cd-rich nanoprecipitates in the matrix, leading to a high power factor of ∼26.76 μW cm-1 K-2 at 773 K in the sintered SnIn0.03Cd0.03Te1.06. Compared with the bulk counterparts, a much lower lattice thermal conductivity is achieved over a wide temperature range because of strong phonon scattering by point defects, nanoprecipitates, lattice distortion, and grain boundaries in the sintered SnIn xCd xTe1+2 x ( x = 3 and 4%) samples. Consequently, a high ZT of ∼1.12 is obtained at 773 K in the p-type SnIn0.03Cd0.03Te1.06, suggesting that nanoprecipitate-included Cd/In codoped octahedron-shaped Sn(CdIn) xTe1+2 x microcrystals are a convincing candidate for medium-temperature thermoelectric applications.
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A novel, tunable, multimodal microwave system for microwave reflectometry system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:093501. [PMID: 30278705 DOI: 10.1063/1.5033968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 08/14/2018] [Indexed: 06/08/2023]
Abstract
Based on a new technique, a tunable, multi-channel system that covers the Q-band (33-55 GHz) is presented in this article. It has a potential use of the Doppler backscattering system diagnostic that can measure the turbulence radial correlation and the perpendicular velocity of turbulence by changing the incident angle. The system consists primarily of a double-sideband (DSB) modulation and a multiplier, which creates four probing frequencies. The probing frequency enables the simultaneous analysis of the density fluctuations and flows at four distinct radial regions in tokamak plasma. The amplitude of the probing frequency can be adjusted by the initial phase of the intermediate frequency (IF) input from the double-sideband, and the typical flatness is less than 10 dB. The system was tested in the lab with a rotating grating, and the results show that the system can operate in the frequency range of 33-55 GHz with a Q-band multitude and that the power of each channel can be adjusted by the phase of the IF input of DSB.
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[Advances in the application of artificial intelligence in cancer diagnosis and treatment]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2018; 26:633-636. [PMID: 30317800 DOI: 10.3760/cma.j.issn.1007-3418.2018.08.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The application of artificial intelligence is developing rapidly in various fields with the improvement of computing power, big data processing, and diversity of algorithms. It has a great potential value in the field of medical and healthcare, especially in the field of cancer diagnosis and treatment. In addition, it can analyze a large amount of data, information, and knowledge instantaneously. Therefore, it serves as a powerful tool for doctors to make the best treatment decisions. Notably, the development of science and technology truly transform into the actual interests of patients. This paper introduces advances in the application of artificial intelligence in diagnosis and treatment of cancer through digital pathology, medical imaging, and genomic medicine.
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Abstract
Objective: To investigate the combination effect of anti-tumor agent rapamycin and anti-autophagy agent chloroquine on osteosarcoma. Methods: The inhibition effect of rapamycin or chloroquine and combination of both on human osteosarcoma cell line 143B measured with CCK-8 box.The combination index at different concentration was calculated, and the synergism effect range was analysed.The effect of combined therapy on cell cycle and apoptosis via flow cytometric was analyzted.Setting up murine subcutaneous xenograft model, the combination effect of antitumor in vivo observed. Results: Either of them, rapamycin or chloroquine had an antitumor effect in vitro (RAPA: IC50=1.5 nmol/L; CQ: IC50=400 μmol/L). When the inhibition rate 40%<fa<70%, the combination had synergism effect (CI<1) at different concentration.Moreover, when CQ at 200 μmol/L, the synergism effect was the most obvious, CI(min)=0.255.The flow cytometric analysis display rapamycin at 1.5 nmol/L had slightly promote apoptosis effect (16.1%±4.4%), and had distinct cell cycle arrest, mainly blocked at G0/G1 phase (73.5%±10.6%; control group: 46.7%±7.7%; P<0.001). While combined with chloroquine, the apoptosis cell obviously increased (21.3%±6.8%; P<0.05). The xenograft model also confirmed that rapamycin combined with chloroquine had a better antitumor effect than single usage (relative tumor proliferation rate; T/C%.CQ: 98.4%±11.6%; RAPA: 65.5%±7.5%; CQ+ RAPA: 42.0%±3.4%). Conclusion: Rapamycin combine with chloroquine can increase the antitumor efficacy, and the combination therapy maybe a potential therapeutic regimen.
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A novel approach to estimating the Doppler shift frequency from quadrature mixer output. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:073503. [PMID: 28764541 DOI: 10.1063/1.4991018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Doppler backscattering systems (DBSs) have been widely used in magnetic confinement fusion devices to measure the density fluctuations and propagation velocity of turbulence. However, the received signals of a DBS usually include both zero-order reflection and backscattering components, which results in interference in calculating the Doppler shift frequency from the backscattering components. A novel method is introduced here for estimating the Doppler shift frequency by separating the zero-order reflection and backscattering components using the cross-phase spectrum between the I-signal and Q-signal from a quadrature mixer, based on the difference in symmetrical characteristics between the zero-order reflection and backscattering signal spectra. It is proven that this method is more effective than traditional approaches, such as multiple signal classification and fast Fourier transformation, for extracting Doppler shift information.
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An eight-channel Doppler backscattering system in the experimental advanced superconducting tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:073504. [PMID: 28764527 DOI: 10.1063/1.4991855] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Doppler backscattering system can measure the perpendicular velocity and fluctuation amplitude of the density turbulence with intermediate wavenumber. An eight-channel Doppler backscattering system has been installed in the Experimental Advanced Superconducting Tokamak (EAST), which can probe eight different radial locations simultaneously by launching eight fixed frequencies (55, 57.5, 60, 62.5, 67.5, 70, 72.5, 75 GHz) into plasma. The quasi-optical system consists of circular corrugated waveguide transmission, a fixed parabolic mirror, and a rotatable parabolic mirror which are integrated with quasi-optics front-end of the profile reflectometer inside the vacuum vessel. The incidence angle can be chosen from 5° to 12°, and the wavenumber range is 2-15/cm with the wavenumber resolution Δk/k≤0.21. Ray tracing simulations are used to calculate the scattering locations and the perpendicular wavenumber. The dynamic range of this new eight-channel Doppler backscattering system can be as large as 40 dB in the EAST. In this article, the hardware design, the ray tracing, and the preliminary experimental results in the EAST will be presented.
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Millimeter-wave imaging diagnostics systems on the EAST tokamak (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:11D901. [PMID: 27910310 DOI: 10.1063/1.4959162] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Millimeter-wave imaging diagnostics, with large poloidal span and wide radial range, have been developed on the EAST tokamak for visualization of 2D electron temperature and density fluctuations. A 384 channel (24 poloidal × 16 radial) Electron Cyclotron Emission Imaging (ECEI) system in F-band (90-140 GHz) was installed on the EAST tokamak in 2012 to provide 2D electron temperature fluctuation images with high spatial and temporal resolution. A co-located Microwave Imaging Reflectometry (MIR) will be installed for imaging of density fluctuations by December 2016. This "4th generation" MIR system has eight independent frequency illumination beams in W-band (75-110 GHz) driven by fast tuning synthesizers and active multipliers. Both of these advanced millimeter-wave imaging diagnostic systems have applied the latest techniques. A novel design philosophy "general optics structure" has been employed for the design of the ECEI and MIR receiver optics with large aperture. The extended radial and poloidal coverage of ECEI on EAST is made possible by innovations in the design of front-end optics. The front-end optical structures of the two imaging diagnostics, ECEI and MIR, have been integrated into a compact system, including the ECEI receiver and MIR transmitter and receiver. Two imaging systems share the same mid-plane port for simultaneous, co-located 2D fluctuation measurements of electron density and temperature. An intelligent remote-control is utilized in the MIR electronics systems to maintain focusing at the desired radial region even with density variations by remotely tuning the probe frequencies in about 200 μs. A similar intelligent technique has also been applied on the ECEI IF system, with remote configuration of the attenuations for each channel.
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Genetic variations in the UTR of genes related to molting in Eriocheir sinensis. GENETICS AND MOLECULAR RESEARCH 2015; 14:12472-8. [PMID: 26505397 DOI: 10.4238/2015.october.16.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Crab grows by periodic molting, which is controlled by molt-inhibiting hormone (MIH) and ecdysteroids. Untranslated regions (UTRs) play crucial roles in the posttranscriptional regulation of gene expression. In this study, using crab collected from Changjiang (Yangtze), Huanghe (Yellow), Liaohe, and Yalujiang rivers, 33 haplotypes of the 3ꞌ-UTR of ecdysteroid-regulated protein (ERP) gene were identified, of which 14 haplotypes were observed in more than one individual. One hundred and forty clones of haplotype h2 (41.5%) were observed in samples from all the 4 rivers. Three haplotypes were observed to be insertions. For the whole crab sample, we found a positive Tajima's D value and a negative Fu's Fs test (Tajima's D value = 0.98726; Fu's Fs test = -27.382), although the P values were not significant (P > 0.10). The network profile of these 33 haplotypes presented a single core pattern with h2 as the core. In this study, we found that the UTR of ERP gene had a considerably high genetic polymorphism among crab from regions south to north of China. Furthermore, we observed a relatively high genetic divergence among different haplotypes, which would suggest a high diversity of the crab gene pool.
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Influence of lithium coating on the optics of Doppler backscatter system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:103503. [PMID: 26520951 DOI: 10.1063/1.4932185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This paper presents the first investigation of the effect of lithium coating on the optics of Doppler backscattering. A liquid lithium limiter has been applied in the Experimental Advanced Superconducting Tokamak (EAST), and a Doppler backscattering has been installed in the EAST. A parabolic mirror and a flat mirror located in the vacuum vessel are polluted by lithium. An identical optical system of the Doppler backscattering is set up in laboratory. The power distributions of the emission beam after the two mirrors with and without lithium coating (cleaned before and after), are measured at three different distances under four incident frequencies. The results demonstrate that the influence of the lithium coating on the power distributions are very slight, and the Doppler backscattering can work normally under the dosage of lithium during the 2014 EAST campaign.
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