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Journal of Advanced Ceramics 2021年第4期10卷 758-767页

作者： Chaokun SONG Yongsheng LIU Fang ye Laifei CHENG Pengfei ZHANG nan CHAI Science and Technology on Thermostructure Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China Beijing Spacecrafts Beijing 100000China Institut fur Materialwissenschaft Technische Universitat DarmstadtDarmstadt D-64287Germany

The SiBCN matrix via chemical vapor infiltration(CVI)or/and polymer infiltration pyrolysis(PIP)technologies was orderly introduced to SiC_(f)/SiC composites to optimize the mechanical property and electromagnetic(EM)shielding effectiveness *** BN interface with the thickness of 350 nm was designed to obtain a little stronger interface *** flexural strength of SiC_(f)/SiC-SiBCN composites reached 545.45±29.59 MPa thanks to the crack deflection between the CVI SiC and CVI SiBCN,as well as CVI SiBCN and PIP SiBCN matrix because of the modulus difference between *** fracture toughness(KiC)with the value of 16.02±0.94 MPa·m^(1/2) was obtained owing to the extension of crack propagation *** adverse effect of stronger interface bonding was eliminated by the design of matrix microstructure for SiC_(f)/SiC-SiBCN *** thermal conductivity in the thickness direction was 7.64 W·(m·K)^(-1) at 1200℃and the electric resistivity decreased to 1.53×10^(3) Ω·*** tunable dielectric property was obtained with the coordination of wave-absorption CVI SiBCN matrix and impedance matching PIP SiBCN matrix,and the total shielding effectiveness(SE_(T))attained 30.01 *** indicates that the SiC_(f)/SiC-SiBCN composites have great potential to be applied as structural and functional materials.

关键词： SiC_(f)/SiC-SiBCN composites chemical vapor infiltration(CVI) polymer infiltration pyrolysis(PIP) mechanical property electromagnetic characteristic

A direct coupling analysis method and its application to the Scientific Research and Demonstration Platform

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Journal of Hydrodynamics 2021年第1期33卷 13-23页

作者： Jun Ding You-sheng Wu Xin-yun Ni Qi-bin Wang Yu-chao Chen Yong-lin ye Xin-yu Zhang Yu-xiang Ma Wei-nan Yang China Ship Scientific Research Center Wuxi 214082China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

Design of a very large floating structure(VLFS)deployed near islands and reefs,different from those in the open sea,inevitably faces new technical challenges including numerical analysis *** this paper,a direct coupling analysis method(DCAM)has been established based on the Boussinesq equations and the three-dimensional hydroelasisity theory with Rankine source method to analyze the responses of a VLFS in shallow sea with complicated geographical *** tests have been carried out to validate the *** further verify the numerical methods and investigate the performance of such a VLFS,a“Scientific Research and Demonstration Platform(SRDP)”was built and deployed in 2019 at the site about 1000 m off an island with water depth around 40m in South China *** is a simplified small model of a two-module semi-submersible-type *** numerical simulation of its responses on severe waves with focus on motions and connector forces is conduct by DCAM,and compared with the on-site *** agreement has been *** approves the DCAM as a feasible tool for design and safety assessment of a VLFS deployed near islands and reefs.

关键词： Very large floating structure(VLFS) hydroelastic analysis near island direct coupling analysis method model test on-site measurement verification

Measurement of Ca^(2+) Flow in Cochlear Cells Using Non-Invasive Micro-Test Technique

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Journal of Otology 2010年第2期5卷 90-96页

作者： CHEN Shi-qin YU Ning ye sheng-nan YANG Shi-ming ZHAI Suo-qiang Department of Otolaryngology Head and Neck Surgery Oto-Neurobiology CentreInstitute of OtolaryngologyChinese PLA General HospitalBeijing 100853China Department of Otolaryngology Affiliated First HospitalFujian Medical UniversityFuzhou 350005China

Objective To test Calcium ion(Ca2+) flow at the head and end of outer hair cells(OHCs) in resting state and in response to Nimodipine *** Non-invasive micro-test techniques were used to study Ca2+ in isolated OHCs in adult guinea *** Four types of Ca2+ transport were identified in OHCs on basilar membrane tissue fragments:influx at the head of with efflux at the bottom(type 1):efflux at the head of OHCs with influx at the bottom(type 2);influx at the both head and bottom(type 3);and efflux at the both head and bottom(type 4).However,only type 1 and type 3 of Ca2+ ion transport were detected in the *** propose that Ca2+ ion transport exists in adult guinea pig cochlear OHCs in resting state and is ***2 + flow in OHC can be inhibited by Nimodipine in resting state.

关键词： Guinea pig outer hair cells Ca2+ ion non-invasive micro-test technique nimodipine.

Bilayer borophene:an efficient catalyst for hydrogen evolution reaction

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 13-23页

作者： Na Xing nan Gao Panbin ye Xiaowei Yang Haifeng Wang Jijun Zhao College of Sciences/Xinjiang Production&Construction Corps Key Laboratory of Advanced Energy Storage Materials and Technologies Shihezi UniversityShihezi832000China Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)Dalian University of TechnologyDalian116024China School of Materials Science and Engineering Taizhou UniversityTaizhou318000China

The electrocatalytic hydrogen evolution reaction is a crucial technique for green hydrogen ***,finding affordable,stable,and efficient catalyst materials to replace noble metal catalysts remains a significant *** experimental breakthroughs in the synthesis of two-dimensional bilayer borophene provide a theoretical framework for exploring their physical and chemical *** this study,we systematically considered nine types of bilayer borophenes as potential electrocatalysts for the hydrogen evolution *** first-principles calculations revealed that bilayer borophenes exhibit high stability and excellent conductivity,possessing a relatively large specific surface area with abundant active *** surface boron atoms and the bridge sites between two boron atoms can serve as active sites,displaying high activity for the hydrogen evolution ***,the Gibbs free energy change associated with adsorption for these bilayer borophenes can reach as low as−0.002 eV,and the Tafel reaction energy barriers are lower(0.70 eV)than those on ***,the hydrogen evolution reaction activity of these two-dimensional bilayer borophenes can be described by engineering their work ***,we considered the effect of pH on hydrogen evolution reaction activity,with significant activity observed in an acidic *** theoretical results reveal the excellent catalytic performance of two-dimensional bilayer borophenes and provide crucial guidance for the experimental exploration of multilayer boron for various energy applications.

关键词： bilayer borophene hydrogen evolution reaction work function pH effect

Crystal structure of kindlin-2 PH domain reveals a conformational transition for its membrane anchoring and regulation of integrin activation

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Protein & Cell 2012年第6期3卷 434-440页

作者： Yan Liu Yun Zhu sheng ye Rongguang Zhang National Laboratory of Biophysics Institute of BiophysicsChinese Academy of SciencesBeijing 100101China

Kindlin-2 belongs to a subfamily of FERM domain con-taining proteins,which plays key roles in activating integrin transmembrane receptors and mediating cell *** to conventional FERM domains,kindlin-2 FERM contains an inserted pleckstrin homology(PH)domain that specifically binds to phosphatidy-linositol(3,4,5)trisphosphate(PIP3)and regulates the kindlin-2 *** have determined the crystal struc-ture of kindlin-2 PH domain at 1.9Åresolution,which reveals a conserved PH domain fold with a highly charged and open binding pocket for PIP3 head *** comparison with a previously reported solution structure of kindlin-2 PH domain bound to PIP3 head group reveals that upon PIP3 insertion,there is a significant conformational change of both the highly positively charged loop at the entry of the PIP3 binding pocket and the entireβbarrel of the PH *** propose that such“induced-fit”type change is crucial for the tight binding of PIP3 to anchor kindlin-2 onto the membrane surface,thereby promoting its binding to *** results provide important structural insight into kindlin-2-mediated membrane anchoring and integrin activation.

关键词： kindlin-2 integrin PH domain crystal structure cell adhesion membrane

Nicotine enhances migration and invasion of human esophageal squamous carcinoma cells which is inhibited by nimesulide

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World Journal of Gastroenterology 2009年第20期15卷 2500-2505页

作者： ye Zong Shu-Tian Zhang sheng-Tao Zhu Department of Gastroenterology Beijing Friendship Hospital Affiliated to the Capital Medical University Beijing Digestive Disease Center Beijing 100050 China

AIM： To study the effect of nicotine on the migration and invasion of human esophageal squamous carcinoma cells and to investigate whether nimesulide can inhibit the effect of ***： The esophageal squamous carcinoma cell line （TE-13） was treated with different concentrations of nicotine （100 μg/mL and 200 μg/mL） or 200 μg/mL nicotine plus 100 μmol/L nimesulide. Cell migration and invasion were measured using migration and invasion chamber systems. COX-2 expression was determined by Western blotting. Matrix metalloproteinase-2 （MMP-2） was analyzed by zymography and ***： Nicotine （100 μg/mL, 200 μg/mL） enhanced TE-13 cells migration and invasion, and increased the protein expression of COX-2 and the activity of MMP-2. Nicotine （200 μ/mL） stimulated TE-13 cells migration and invasion which were partly blocked by nimesulide. This was associated with decreased protein expression of COX-2 and decreased activity and protein expression of MMP-2. CONCLUSION： Nicotine enhances the migration and invasion of the esophageal squamous carcinoma cell line, and nimesulide partly blocks the effect ofnicotine-enhanced esophageal squamous carcinoma cell migration and invasion.

关键词： Carcinoma Cyclooxygenase 2 inhibitors Esophagus Nicotine Squamous cell

Silicate-doped hydroxyapatite and its promotive effect on bone mineralization

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Frontiers of Materials Science 2013年第1期7卷 40-50页

作者： Zhi-ye QIU In-Sup NOH sheng-Min ZHANG Advanced Biomaterials and Tissue Engineering Center Huazhong University of Science and Technology Wuhan 430074 China Department of Materials Science and Engineering Tsinghua University Beijing 100084 China Department of Chemical and Biological Engineering Seoul National University of Science and Technology Seou1139743 Korea

Bone defect is one of the most common diseases in clinic. Existing therapeutic approaches have encountered many problems, such as lack of autogenous allogeneic bone and immunological rejection to allogeneic implant. Synthetic hydroxyapatite (HA) provided solutions for bone repair, since the HA is the main inorganic component of animals’ bone. However, HA has good biocompatibility, but does not possess osteogenic capability, which is of significance for modern bone repair materials. Si is an essential trace element in bone tissue, and it has been demonstrated to be able to promote bone formation. Therefore, silicate-doped hydroxyapatite (Si-HA) may serve as a promising material for bone repair, and promote bone regeneration in the repair. The current review discusses development of Si-HA, focusing on its preparation and characterization, in vitro and in vivo evaluations of the material, positive effect of Si-HA on promoting bone formation in clinical applications, and molecular mechanism investigation of such promotive effect.

关键词： silicate-doped hydroxyapatite (Si-HA) osteogenesis collagen biosynthesis bone mineralization

Effect of permafrost degradation on hydrological processes in typical basins with various permafrost coverage in Western China

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Science China Earth Sciences 2011年第4期54卷 615-624页

作者： NIU Li ye Baisheng LI Jing sheng Yu State Key Laboratory of Co ospheric Sciences Cold & Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Frozen Soil Engineering Cold & Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Monthly discharge of four rivers with various permafrost coverage and little anthropogenic influence was used to identify effects of permafrost degradation during the last 50 years,which has occurred because of significant increases in air temperature in the river *** basins of the Shule,Heihe,Shiyang and upper yellow Rivers in northwestern China have 73%,58%,33% and 43% permafrost coverage,*** is snow cover in the basins and no rain to supply rivers during winter. The monthly recession coefficient(RC) in winter reflects groundwater *** RC has increased obviously for the Shule and Heihe rivers with 73% and 58% permafrost coverage,respectively,but did not increase for the Shiyang River,and decreased insignificantly for the upper yellow River,which had less permafrost *** is a distinct positive relationship between RC and annual negative degree-day temperature(NDDT) at the meteorological stations in the basins with high permafrost *** results imply that permafrost degradation due to climate warming affects hydrological processes in *** effect is obvious in the basins with high permafrost coverage but negligible in those with low permafrost coverage. Permafrost degradation increases infiltration,enlarges the groundwater reservoir,and leads to slow discharge *** result means that hydrological processes are affected strongly by permafrost degradation in river basins with high permafrost coverage,but less in river basins with less permafrost coverage.

关键词： hydrology permafrost climate change

May Chronic Childhood Constipation Cause Oxidative Stress and Potential Free Radical Damage to Children?

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Biomedical and Environmental Sciences 2004年第3期17卷 266-272页

作者： JI-YUEWANG ye-LINGWANG sheng-LIZHOU JUN-FUZHOU SecondAffiliatedHospitalCollegeofMedicine ZhejiangUniversity88JiefangRoadHangzhou310009ZhejiangChina AffiliatedChildren＇sHospital CollegeofMedicineZhejiangUniversity57ZhuganLaneHangzhou310003ZhejiangChina

Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress and potential free radical damage to chronic constipation patients (CCPs). Methods Sixty CCPs and sixty healthy child volunteers (HCVs) whose ages, gender and others were matched for the CCPs were enrolled in a randomized controlled study, in which levels of vitamin C (VC) and vitamin E (VE) in plasma as well as activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with average values of the above biochemical parameters in the HCVs group, the average values of VC and VE in plasma as well as those of SOD and CAT in erythrocytes in the CCPs group were significantly decreased (P<0.0001). Linear regression and bivariate correlation analysis showed that with prolonged course of the CCPs, the levels of VC and VE in plasma as well as the activities of SOD and CAT in erythrocytes in the CCPs were decreased gradually (P<0.0001). Conclusion The findings in the present study suggest that chronic childhood constipation causes oxidative stress and potential free radical damage to children with chronic constipation.

关键词： Chronic childhood constipation Oxidative stress Free radicals Free radical damage Antioxidant Antioxidase

miRNA-26b suppresses the TGF-β2-induced progression of HLE-B3 cells via the PI3K/Akt pathway

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International Journal of Ophthalmology(English edition) 2021年第9期14卷 1350-1358页

作者： En Shi Xiang-nan ye Liu-Yi Xie Department of Ophthalmology Ningbo Eye HospitalNingbo 315040Zhejiang ProvinceChina Department of Ophthalmology Ningbo Medical Center Lihuili HospitalNingbo 315041Zhejiang ProvinceChina Department of Ophthalmology Beilun District Peopled HospitalNingbo 315826Zhejiang ProvinceChina

AIM:To study the effect of mi R-26 b on lens epithelial cells induced by transforming growth factor beta(TGF-β)2 and the underlying signaling ***:Human lens epithelial cell line B-3(HLE-B3)was incubated with TGF-β2(5 ng/m L)and then transfected with mi R-26 b *** expression of mi R-26 b was determined using quantitative reverse transcriptase polymerase chain reaction(q RT-PCR),while 5’-bromodeoxyuridine(Brd U)and wound-healing assays were used to measure the growth and migration of HLE-B3 cells,*** expression of epithelialmesenchymal transition(EMT)markers and the activity of the phosphatidylinositol 3-kinase(PI3 K)/Akt pathway were measured by Western blotting assay and immunofluorescence *** microscopy was also used to observe cellular ***:The expression levels of mi R-26 b were significantly reduced in human posterior capsular opacification-attached lens tissue and TGF-β2-stimulated HLE-B3 *** the presence of TGF-β2,the growth,migration,and EMT of HLE-B3 cells were distinctly enhanced;these effects were attenuated by the administration of mi R-26 b ***,the overexpression of mi R-26 b significantly reduced upregulation of the PI3 K/Akt pathway when stimulated by TGF-β2 in HLE-B3 ***,the addition of an activator(740 Y-P)led to the upregulation of the PI3 K/Akt pathway and abolished the protective effect of mi R-26 b on the HLE-B3 cells that was mediated by TGF-β***:The mi R-26 b suppresses TGF-β2-induced growth,migration,and EMT in HLE-B3 cells by regulating the PI3 K/Akt signaling pathway.

关键词： posterior capsule opacification miRNA-26b proliferation migration epithelial-mesenchymal transition