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Causal effects of circulating vitamin levels on the risk of heart failure:a Mendelian randomization study

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Journal of Geriatric Cardiology 2023年第3期20卷 195-204页

作者： bo GUAN Xiao-Qiang CHEN Yan liU Hui ZHOU Ming-Yan YANG hong-Wei zheng Shi-Jun li Jian CAO Medical School of Chinese PLA General Hospital BeijingChina Department of Cardiology Shanghai General HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Xiangya School of Nursing Central South UniversityChangshaHunanChina Department of Cardiology Tangshan Gongren Hospital Affiliated to Hebei Medical UniversityTangshanChina Geriatric Cardiology Department of the Second Medical Center and National Clinical Research Center for Geriatric Diseases Chinese PLA General HospitalBeijingChina

BACKGROUND Observational studies suggest inverse associations between serum vitamin levels and the risk of heart failure(HF). However, the causal effects of vitamins on HF have not been fully elucidated. Here, we conducted a Mendelian randomization(MR) study to investigate the causal associations between genetically determined vitamin levels and *** Genetic instrumental variables for circulating vitamin levels, including vitamins A, B, C, D, and E, which were assessed as either absolute or metabolite levels were obtained from public genome-wide association studies. Summary statistics for single-nucleotide-polymorphisms and HF associations were retrieved from the HERMES Consortium(47,309 cases and 930,014controls) and FinnGen Study(30,098 cases and 229,612 controls). Two-sample MR analyses were implemented to assess the causality between vitamin levels and HF per outcome database, and the results were subsequently combined by *** Our MR study did not find significant associations between genetically determined circulating vitamin levels and HF risk. For absolute vitamin levels, the odds ratio for HF ranged from 0.97(95% confidence interval [CI]: 0.85–1.09, P = 0.41) for vitamin C to 1.05(95% CI: 0.61–1.82, P = 0.85) for vitamin A. For vitamin metabolites, the odds ratio ranged between 0.94(95% CI:0.75–1.19, P = 0.62) for α-tocopherol and 1.11(95% CI: 0.98–1.26, P = 0.09) for γ-*** Evidence from our study does not support the causal effects of circulating vitamin levels on HF. Therefore,there may be no direct beneficial effects of vitamin intake on the prevention of primary HF.

关键词： vitamin prevention absolute

Sulfonate-Functionalized Polyoxovanadate-Based Metal-Organic Polyhedra for Enhanced Proton Conduction via the Synergy of linker and Metal Cluster Vertex

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Chinese Journal of Structural Chemistry 2022年第8期41卷 12-17页

作者： Yu Zhang Shan-Shan liu bo li Hanqi You Longxi Zhang Zhenyi Zhang hong-Ying Zang Qi zheng Weimin Xuan College of Chemistry Chemical Engineering and Biotechnology&State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsDonghua UniversityShanghai 201620China Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education at Universities of Jilin Province Faculty of ChemistryNortheast Normal UniversityChangchun 130024China Bruker(Beijing)Scientific Technology Co. Ltd 9FBuilding No.1Lane 2570Hechuan RdMinhang DistrictShanghai 200233China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

Metal-organic polyhedra(MOPs)have emerged as novel porous platforms for proton conduction,however,the concerted employment of both linker and metal cluster vertex is rarely applied for the fabrication of MOPs-based high conducting *** we report the synthesis of sulfonate-functionalized polyoxovanadate-based MOPs for enhanced proton conduction via the synergistic effect from linker and metal cluster *** 1 and 2 exhibit octahedral cage configuration constructed from{V_(5)O_(9)Cl}vertex and 5-sulfoisophthalate *** to the ordered packing of octahedral cages along three axes,3D interpenetrated open channels that are lined with high-density sulfonates are thus formed within *** with the proton-conductive{V_(5)O_(9)Cl}vertexs as well as protonated counterions,an extensive H-bonded network is therefore generated for facile proton transfer.2 exhibits high proton conductivity of 3.02×10^(-2)S cm^(-1)at 65℃under 90%RH,recording the highest value for MOPs pellet *** value is enhanced~1order of magnitude compared with that of carboxylate-functionalized analogue 3,clearly illustrating the advantage of combining linker and metal cluster node for enhanced proton *** work will further promote the exploitation of high proton conductive MOPs-based materials by the synergy design strategy.

关键词： metal-organic polyhedra proton conduction polyoxovanadate synergistic effect

Gas microchannel plate-pixel detector for X-ray polarimetry

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Nuclear Science and Techniques 2024年第5期35卷 60-73页

作者： Huan-bo Feng hong-Bang liu Dong Wang Zi-li li Shu-lin liu Qian liu Hang-Zhou li Bin-Long Wang Yan-Jun xie Zong-Wang Fan Hui Wang Ran Chen Di-Fan Yi Rui-Ting Ma Fei xie bo Peng Xiang-Ming Sun Jin li En-Wei liang Present Address:Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China PLAC Key Laboratory of Quark and Lepton Physics(MOE)Central China Normal UniversityWuhan 430079China School of Science Huzhou UniversityHuzhou 313000China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China School of Physical Science University of Chinese Academy of SciencesBeijing 100049China The 13th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050057China

POLAR-2 is a gamma-ray burst(GRB)polarimeter that is designed to study the polarization in GRB radiation emissions,aiming to improve our knowledge of related ***-2 is expected to utilize an on-board polarimeter that is sensitive to soft X-rays(2-10 keV),called low-energy polarization *** have developed a new soft X-ray polari-zation detector prototype based on gas microchannel plates(GMCPs)and pixel chips(Topmetal).The GMCPs have bulk resistance,which prevents charging-up effects and ensures gain stability during *** detector is composed of low outgassing materials and is gas-sealed using a laser welding technique,ensuring long-term stability.A modulation factor of 41.28%±0.64% is obtained for a 4.5 keV polarized X-ray beam.A residual modulation of 1.96%±0.58% at 5.9 keV is observed for the entire sensitive area.

关键词： X-ray polarimetry Gas microchannel plate-pixel detector Gamma-ray bursts

Structure and magnetic properties of TbCu_7-type melt-spun Sm–Fe–B alloys

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Rare Metals 2019年第2期38卷 151-156页

作者： Chuan-Jiang zheng Yang Luo Dun-bo Yu Wen-Long Yan hong-Wei li Yong-Jun Mao Shuo Lu Ning-Tao Quan National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd.

The melt-spun SmFe_(12)B_x(x = 0, 0.50, 0.75,1.00, 1.25 and 1.50) ribbons were prepared at 40 m·s^(-1),and their structure and magnetic properties were studied by powder X-ray diffraction(XRD), vibrating sample magnetometer(VSM) and transmission electron microscopy(TEM). XRD results indicate that SmFe_(12)B_x alloys with 0.50 ≤ x ≤ 1.00 are composed of single-phase TbCu_7-type structure. Moreover, it is found that the boron addition can inhibit the emergence of soft magnetic phase a-Fe and result in the increase in the axial ratio c/a. After annealing at 650 ℃ for 0.5 h, the metastable phase TbCu_7 initially decomposes into the stable phase Sm_2Fe_(14)B(Nd_2Fe_(14)B-type) and a-Fe. The value of magnetic moment per Fe atom increases slightly from 1.75 uB for boron-free sample to 1.80 uB for the x = 0.75 sample and then decreases *** addition, the best magnetic properties of maximum energy product [(BH)_(max)] of 14.56 kJ·m^(-3), coercivity(H_(cj))of 172.6 kA·m^(-1) and remanence(B_r) of 0.45 T are obtained for the SmFe_(12)B_(1.00) alloy. Based on transmission electron microscopy(TEM) results, the average size of grains is around 197 nm for B-free sample and decreases to 95 nm for x = 1.00 sample, indicating that the addition of boron can refine grains.

关键词： TbCu7-type structure Sm-Fe-B ribbons Phase formation Magnetic moment Microstructure

Non-parabolic effect for femtosecond laser-induced ultrafast electro-absorption in solids

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Chinese Physics B 2020年第1期29卷 446-451页

作者： li-bo liu hong-Xiang Deng Xiao-Tao Zu Xiao-Dong Yuan Wan-Guo zheng School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900China

A theoretical study for femtosecond laser-induced ultrafast electro-absorption of bulk solids is *** numerical results show that,in the case of low intensity of the pump laser where the interaction between the pump laser and solids is in the multi-photon regime,the energy band of solids can be approximately taken as a parabolic band and electro-absorption spectrums from the parabolic band and real band are nearly the ***,in the case of high intensity where the interaction is in the tunneling regime,spectrums from the parabolic band and real band are quite *** physical mechanism for the difference in the tunneling regime is *** find that the non-parabolic parts of the real energy band and Bragger scattering of electrons near the first Brillouin zone boundaries,which are neglected in previous studies,strongly influence the electro-absorption spectrum in the tunneling *** two physical processes cause the difference of *** theoretical results are in accordance with the experiment result.

关键词： ultrafast electro-absorption red-shift of absorption edge Bragger scattering effect multi-photon process

Choledochoduodenal fistula caused by migration of endoclip after laparoscopic cholecystectomy

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World Journal of Gastroenterology 2014年第16期20卷 4827-4829页

作者： Tao hong xie-Qun Xu Xiao-Dong He Qiang Qu Bing-Lu li Chao-Ji zheng Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical College

The wide use of surgical endoclips in laparoscopic surgery has led to a variety of *** endoclips migrating into the common bile duct after laparoscopic cholecystectomy is rare.A migrated endoclip can cause obstruction,serve as a nidus for stone formation,and cause *** the exact pathogenesis is still unknown,it is probably related to improper clip application,subclinical bile leak,inflammation,and subsequent necrosis,allowing the clips to erode directly into the common bile *** present a case of endoclip migrating into the common bile duct and duodenum,resulting in choledochoduodenal fistula after laparoscopic cholecystectomy and a successful reconstruction of the biliary tract by a hepaticojejunostomy with a Roux-en-Y *** case shows that surgical endoclips can penetrate into the intact bile duct wall through serial maceration,and it is believed that careful application of clips may be the only way to prevent their migration after laparoscopic cholecystectomy.

关键词： Biliary obstruction Laparoscopic cholecystectomy Choledochoduodenal fistula

A nonlinear creep damage model for gelled waxy crude

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Petroleum Science 2022年第4期19卷 1803-1811页

作者： hong-Ying li Qing-bo xie Hao Sun Wei Guo Feng Yan Qing Miao Chao-Fei Nie Yu Zhuang Qian Huang Jin-Jun Zhang National Engineering Laboratory for Pipeline Safety/MOE Key Laboratory of Petroleum Engineering/Bejing Key Laboratory of Urban Oil&Gas Distribution Technology/China Universityof Petroleum Beijing102249China PipeChina Pipeline R&DCenter Langfang065000China Jinan Urban Planning and Design Institute Jinan250101China

Yielding behaviors of waxy crude oil is one of the key issues of flow assurance challenges. The yielding of waxy crude under constant stress is actually a creep process of strain accumulation to structural failure,to describe the process completely and accurately is the basis of numerical simulation of restart process of the pipeline. The creep and yield behaviors of two gelled waxy crudes were investigated experimentally under different constant applied stresses. The results clearly show that the creep process of waxy crude is related to the applied stress and time. The greater the applied stress, and the longer the loaded time, the more obvious the nonlinear features. Based on the fractional calculus theory, a fractional viscous element was developed to describe the decelerated and steady creep process of gelled waxy crude. On the basis of the damage theory, an elastic damage element was proposed to describe the accelerated creep after the yielding. According to the idea of mechanical analogy, a nonlinear creep model was established by a fractional viscous element, an elastic damaged element, and an elastic element in series, which can accurately describe the whole creep and yielding process of gelled waxy crude.

关键词： Waxy crude oil Rheology Yield Creep Constitutive model Mechanical analogy

Development of two methods for rapid screening of recombinant Pichia pastoris strains with high-level expression of β-mannanase

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Journal of Central South University 2015年第11期22卷 4162-4167页

作者：李古月郑甲周洪波 School of Minerals Processing and Bioengineering Central South University Key Laboratory of Biometallurgy of Ministry of Education (Central South University)

The yeast Pichia pastoris(P. pastoris) has been used for the expression of heterologous proteins with the significant success. However, it is time-consuming to screen the high expression level of the recombinant P. pastoris directly. Thus, for β-mannanase production, developing the accurate, rapid and inexpensive screening method to substitute random screening is certainly required. A simple method based on the size of hydrolysis hole was described here, but this method was not very accurate that could only be used in preliminary screening. To further improve the accuracy, a micro-plate screening method is established, which appears to be more accurate and effective. The efficiency of this screening method is about 10 times higher than that of the general screening strategy of cultivation in shaking flasks. Two methods presented here can also be used for screening of recombinant Pichia strains with high-level expression of other heterologous protein after modification.

关键词： β-mannanase Pichia pastoris high-production strain

Tuning SMSI to stabilize metallic Pd species:A case study on Pd/TiO_(2) for HCHO oxidation

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Chinese Chemical Letters 2024年第3期35卷 162-166页

作者： Chunying Wang Xiaofeng liu Jingyi Wang Yaobin li Shaohua xie Fudong liu Changbin Zhang Yuming zheng Wenpo Shan hong He Center for Excellence in Regional Atmospheric Environment Key Laboratory of Urban Pollutant ConversionInstitute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control Ningbo Urban Environment Observation and Research StationChinese Academy of SciencesNingbo 315800China Department of Civil Environmentaland Construction Engineering(CECE)Catalysis Cluster for Renewable Energy and Chemical Transformations(REACT)Nano Science Technology Center(NSTC)University of Central FloridaOrlandoFL 32816USA State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China

Pretreatment of the carrier for supported catalysts can effectively improve the strong metal-support interaction(SMSI)and increase the dispersion of precious metals,which are critical to many important catalytic *** this work,we tuned SMSI on Pd/TiO_(2)catalysts through inducing surface defects of TiO_(2)by pretreated with different atmospheres(H_(2)/N_(2),N_(2),O_(2)/N_(2))at the high temperature(800℃).Multiple characterization results illustrated that surface defects anchored Pd species and thus enhanced their *** reduction,Ti^(3+)species formed and transferred onto the metallic Pd species and then induced SMSI,which effectively stabilize Pd species in the metallic *** stronger MSI,the more stability of Pd *** a case,Pd/TiO_(2)–800H_(2),with strongest MSI,displayed the best HCHO oxidation performance at low temperature(10℃).

关键词： Pd/TiO_(2) Surface defects SMSI Formaldehyde Stability of Pd species