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Wuhan University Journal of Natural Sciences 2019年第1期24卷 45-56页

作者： ZHAI Qiuran QIN Qian chen Peng CUI Zhihui WANG Jiao ZHANG Jianxiang WANG Shoujun Endocrinology Department The First Affiliated Hospital of Zhengzhou University Physical Examination Center The First Affiliated Hospital of Zhengzhou University Endocrinology Department Zhengzhou Central Hospital

This study investigated the specific mechanism of knockdown of neuropeptide y(NPy) in reducing obesity-induced insulin resistance in the white adipose tissue. Adeno-associated virus(AAV)-mediated RNAi was utilized to downregulate NPy expression in rats fed either regular chow or high fat diet. By investigating the differences in rat body weight and food intake, we assessed the effect of knockdown of NPy expression on insulin sensitivity and β-cell proliferation. Glucose consumption and 2-[3 H]DG uptake in 3 T3-L1 adipocytes were assessed to determine the molecular mechanisms. The results showed that knockdown of NPy expression in the dorsomedial hypothalamus(DMH) reduced obesity-induced insulin resistance, increased glucose consumption, and decreased 2-[3 H]DG uptake in 3 T3-L1 adipocytes via the PI3 K/Akt/GSK-3β signaling pathways and the NPy y5 receptor.

关键词： knockdown of neuropeptide y(NPy) insulin resistance glucose consumption glucose intake PI3K/Akt/GSK-3βsignaling pathways

RsaL is a self-regulatory switch that controls alternative biosynthesis of two AHL-type quorum sensing signals in Pseudomonas aeruginosa PA1201

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mLife 2024年第1期3卷 74-86页

作者： ya-Wen He Zi-Jing Jin ying Cui Kai Song Bo chen Lian Zhou State Key Laboratory of Microbial Metabolism Joint International Research Laboratory of Metabolic and Developmental SciencesSJTU-NLBP Joint R&D Centre for Biopesticides and BiofertilizersSchool of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina Zhiyuan Innovative Research Centre Student Innovation CentreZhiyuan CollegeShanghai Jiao Tong UniversityShanghaiChina

Pseudomonas aeruginosa is a ubiquitous and metabolically versatile microorganism naturally found in soil and *** is also an opportunistic pathogen in plants,insects,animals,and *** response to increasing cell density,*** uses two acylhomoserine lactone(AHL)quorum-sensing(QS)signals(i.e.,N-3-oxo-dodecanoyl homoserine lactone[3-oxo-C12-HSL]and Nbutanoyl-homoserine lactone[C4-HsL]),which regulate the expression of hundreds of ***,how the biosynthesis of these two QS signals is coordinated remains *** studied the regulation of these two QS signals in the rhizosphere strain ***1201 sequentially produced 3-oxo-C12-HSL and C4-HSL at the early and late growth stages,*** highest 3-oxo-C12-HSL-dependent elastase activity was observed at the early stage,while the highest C4-HSL-dependent rhamnolipid production was observed at the late *** atypical regulator RsaL played a pivotal role in coordinating 3-oxo-C12-HSL and C4-HSL biosynthesis and QS-associated *** repressed las/transcription by binding the-10 and-35 boxes of the lasl *** contrast,RsaL activated rhll transcription by binding the region encoding the 5'-untranslated region of the rhll ***,RsaL repressed its own expression by binding a nucleotide motif located in the-35 box of the rsaL ***,RsaL acts as a molecular switch that coordinates the sequential biosynthesis of AHL QS signals and differential virulence in ***,C4-HSL activation by RsaL was independent of the Las and Pseudomonas quinolone signal(PQS)QS signaling ***,we propose a new model of the QS regulatory network in PA1201,in which RsaL represents a superior player acting at the top of the hierarchy.

关键词： N-3-oxo-dodecanoyl homoserine lactone N-butanoyl-homoserine lactone Pseudomonas aeruginosa quorum sensing RsaL

Application of three-dimensional digitalized reconstruction of latissimus dorsi myocutaneous flap

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Frontiers of Medicine 2008年第1期2卷 45-50页

作者： yuanzhi ZHANG Jianwei LI yanbing LI Dan JIN Jionghao chen Shizhen ZHONG Guoxian PEI Department of Orthopaedics and Traumatology Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China Department of Anatomy University of South ChinaHengyang 421001China Institute of Anatomy Southern Medical UniversityGuangzhou 510515China

Developments of digital technology and three-dimensional(3D)reconstruction allowed a precise description of anatomic *** the introduction of Visible Human Project and Virtual Chinese Human(VCH)techniques,more detailed anatomic images could be *** visible models of these structures can be applied as a useful tool in clinical *** aim of this study was to reconstruct the normal structures of thoracodorsal artery in 3D images and to establish the digitized visible models of latissimus dorsi myocutaneous(LDM)*** cross-sectional images from the four VCH datasets were reviewed to study LDM and thoraco-dorsal artery structures on a section-by-section ***,two adult fresh cadaver specimens were perfused with lead oxide-gelatine mixture and subject to radio-graphic CT scanning on their *** cross-sectional images from the CT images were reviewed to study thor-acodorsal artery ***-dimensional computer-ized reconstructions of LDM flap structures were conducted from these datasets by using Amira 3.1(TGS)software *** 3D reconstructed visible models established from these datasets perfectly displayed the anatomic characteristics of LDM flap.

关键词： latissimus dorsi myocutaneous imaging three-dimensional Virtual Chinese Human digital technique

Study of pyrolyzed hemin/C as non-platinum cathodic catalyst for direct methanol fuel cells

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Science China Chemistry 2010年第9期53卷 2057-2062页

作者： Qiang Wang Zhiyou Zhou DeJun chen JianLong Lin FuSheng Ke GuiLiang Xu ShiGang Sun Xiamen Univ Dept Chem State Key Lab Phys Chem Solid Surfaces Coll Chem & Chem Engn Xiamen 361005 Peoples R China

Biological reduction of O2 to H2O justifies a serious look at heme as a potential O2 reduction reaction(ORR) catalyst for low temperature fuel *** this study,a novel non-platinum electrocatalyst for ORR was prepared through hemin,which is hydrochloride of heme,supported on Black Pearls 2000 carbon black(Hm-BP) pyrolyzed at 700-900℃ in Ar *** physical and electrocatalytic properties of as-prepared catalysts were characterized by TGA,XRD,XPS,TEM,rotating disk electrode(RDE) and rotating ring disk electrode(RRDE).It has found that the catalyst treated at 750℃(Hm-BP-750) exhibits the best property among the Hm-BP catalysts *** onset potential of ORR on the Hm-BP-750 at 30℃ was measured ca.0.90 V(***) in 0.1 M H2SO4,and mass current density was reached 15.3 mA mg-1 at 0.75 *** has revealed that O2 could be reduced directly to water in a 4e process between 0.9 and 0.83V,and the yield of H2O2 was 0-18% in the potential range of 0.83-0.63 *** methanol-tolerant catalyst also presents excellent stability in medium-term test of direct methanol fuel cell at 80℃.

关键词： hemin heme non-platinum catalyst oxygen reduction direct methanol fuel cell

Quantum phase transition of cold atoms trapped in optical lattices

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Frontiers of physics 2012年第2期7卷 223-234页

作者： yao-hua chen (1) Wei Wu (1) Guo-cai Liu (1) Hong-shuai Tao (1) Wu-ming Liu (1) 1. Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

We review our recent theoretical advances in phase transition of cold atoms in optical lattices, such as triangular lattice, honeycomb lattice, and Kagome lattice. By employing the new developed numerical methods called dynamical cluster approximation and cellular dynamical mean-field theory, the properties in different phases of cold atoms in optical lattices are studied, such as density of states, Fermi surface and double occupancy. On triangular lattice, a reentrant behavior of phase translation line between Fermi liquid state and pseudogap state is found due to the Kondo effect. We find the system undergoes a second order Mott transition from a metallic state into a Mott insulator state on honeycomb lattice and triangular Kagom~ lattice. The stability of quantum spin Hall phase towards interaction on honeycomb lattice with spin-orbital coupling is systematically discussed. And we investigate the transition from quantum spin Hall insulator to normal insulator in Kagom~ lattice which includes a nearest-neighbor intrinsic spin-orbit coupling and a trimerized Hamiltonian. In addition, we propose the experimental protocols to observe these phase transition of cold atoms in optical lattices.

关键词： quantum phase transition optical lattice DMFT spin-orbit coupling

Variations of Laohugou Glacier No.12 in the western Qilian Mountains, China, from 1957 to 2015

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Journal of Mountain Science 2018年第1期15卷 25-32页

作者： LIU yu-shuo QIN Xiang chen Ji-zu LI Zhen-lin WANG Jing DU Wen-tao GUO Wan-qin State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Qilian Shan Station of Glaciology and Ecologic Environment Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Geomatics Center of Gansu Province Gansu Bureau of Surveying Mapping and Geoinformation

Glaciers were solid reservoirs and important water resources in western China,but they were retreating significantly in context of global *** Glacier No.12 was the largest valley glacier in Qilian *** this study,realtime kinematic(RTK)data,topographic map and World View-2 satellite imagery were used to measure changes in terminus,extent and volume of Laohugou Glacier *** showed that Laohugou Glacier No.12 was shrinking significantly since ***1960 to 2015,the terminus reduction of Laohugou Glacier No.12 was 402.96 m(3.99%)in total,and glacier length decreased to 9.7 km from 10.1 *** of glacier area and volume were the most *** 1957 to 2015,glacier area and volume decreased by 1.54 km^2(7.03%)and 0.1816 km^3,*** trend of terminus and area was slowing in 1950-1980s,even stable for a period in the mid-1980s,and then *** core analysis result and nearly meteorological station data shown an increasing trend of temperature in 1957-2015,it was a main reason of continuous retreating of Laohugou Glacier No.12.

关键词： Glacier changes Laohugou Glacier No.12 Qilian Mountains Real-time kinematic Remote sensing image

Al-Si-Fe铸造铝合金的搅拌摩擦加工组织和性能研究

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稀有金属 2019年第12期43卷 1275-1282页

作者：陈涛宋东福陈胜迁龚航陈立华东交通大学理工学院江西南昌3301003 广东省材料与加工研究所广东广州510650 张家界航空工业职业技术学院湖南张家界427000

对不同热处理状态的Al-Si-Fe铸造铝合金进行了搅拌摩擦改性,采用光学显微镜(OM)、扫描电镜(SEM)、拉伸试验机、显微硬度仪等研究了合金状态及改性后热处理对合金组织和性能的影响。结果表明:搅拌摩擦加工后合金的铸造缺陷消失,但存在明... 详细信息

对不同热处理状态的Al-Si-Fe铸造铝合金进行了搅拌摩擦改性,采用光学显微镜(OM)、扫描电镜(SEM)、拉伸试验机、显微硬度仪等研究了合金状态及改性后热处理对合金组织和性能的影响。结果表明:搅拌摩擦加工后合金的铸造缺陷消失,但存在明显的组织不均匀性和不对称性,源于前进侧的带状组织均匀性和细化程度均高其它区域,而铸态合金更容易获得带状组织。改性后第二相的平均长度和圆整度均大幅改善,长度最大减小90%以上,而圆整度则提高7倍以上。相比于T6态合金,铸态合金的改性效果更好,且富铁相的细化效果较共晶硅好。改性后T6热处理对富铁相的长度和圆整度均略有改善,而共晶硅略有长大,圆整度大幅提高。改性后合金的延伸率提高了4.3倍以上,而强度则与改性前合金状态相关。改性前未处理的合金强度、硬度略有提高,而改性前T6处理的合金的强度、硬度大幅降低。当铸态合金经改性后进行T6热处理,获得的组织最为均匀、细小,综合力学性能最佳。

关键词： Al-Si-Fe合金搅拌摩擦加工富铁相共晶硅

A Bioinspired Platform for Effective Delivery of Protein Therapeutics to the Central Nervous System

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A Bioinspired Platform for Effective Delivery of Protein The...

A Policy Integration Method Based on Multilevel Security for Data Integration

第十五届中国实验动物科学年会

作者： Di Wu Meng Qin Duo Xu Lan Wang Chaoyong Liu Jie Ren George Zhou chen chen Fengmei yang yanyan Li yuan Zhao Ruyi Huang Sina Pourtaheri Chunsheng Kang Masakazu Kamata Irvin S.y.chen Zhanlong He Jing Wen Wei chen yunfeng Lu Department of Chemical and Biomolecular Engineering University of California Los Angeles College of Life Science and Technology Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Institute of Medical Biology Chinese Academy of Medical Sciences and Peking Union Medical College

Central nervous system (CNS) diseases are the leading cause of morbidity and mortality;their treatment,however,remains constrained by the blood–brain barrier (BBB) that impedes the access of most therapeutics to the brain.A CNS delivery platform for protein therapeutics,which is achieved by encapsulating the proteins

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Wuhan University Journal of Natural Sciences 2015年第6期20卷 483-489页

作者： WANG Xinming TAN Haoxiang chen Kaijun TANG Hua ZHAO Gansen TANG yong NIE Ruihua School of Computer Science South China Normal University

Integrating and sharing data from different data sources is one of the trends to make better use of data. However, data integration hampers data confidentiality where each data source has its own access control policy. This paper includes a discussion on the issue about access control across multiple data sources when they arc combined together in the scenario of searching over these data. A method based on multilevel security for data integration is proposed. The proposed method allows the merging of policies and also tackles the issue of policy conflicts between different data sources.

关键词： policy integration multilevel security data integra-tion data confidentiality

Estimation of aboveground biomass using in situ hyperspectral measurements in five major grassland ecosystems on the Tibetan Plateau

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Journal of Plant Ecology 2008年第4期1卷 247-257页

作者： Miaogen Shen yanhong Tang Julia Klein Pengcheng Zhang Song Gu Ayako Shimono Jin chen State Key Laboratory of Earth Surface Processes and Resource Ecology Academy of Disaster Reduction and Emergency ManagementBeijing Normal UniversityBeijing 100875China National Institute for Environmental Studies TsukubaIbaraki 305-8569Japan Colorado State University Fort CollinsCO 80523USA Terrestrial Ecology Lab Graduate School of Life and Environment ScienceUniversity of TsukubaTennodai 1-1-1TsukubaIbaraki 305-8577Japan Northwest Plateau Institute of Biology Chinese Academy of ScienceXining 810001China

Aims There are numerous grassland ecosystem types on the Tibetan *** include the alpine meadow and steppe and degraded alpine meadow and *** study aimed at developing a method to estimate aboveground biomass(AGB)for these grasslands from hyperspectral data and to explore the feasibility of applying air/satellite-borne remote sensing techniques to AGB estimation at larger *** We carried out a field survey to collect hyperspectral reflectance and AGB for five major grassland ecosystems on the Tibetan Plateau and calculated seven narrow-band vegetation indices and the vegetation index based on universal pattern decomposition(VIUPD)from the spectra to estimate ***,we investigated correlations between AGB and each of these vegetation indices to identify the best estimator of AGB for each ecosystem ***,we estimated AGB for the five pooled ecosystem types by developing models containing dummy *** last,we compared the predictions of simple regression models and the models containing dummy variables to seek an ecosystem type-independent model to improve prediction of AGB for these various grassland ecosystems from hyperspectral *** findings When we considered each ecosystem type separately,all eight vegetation indices provided good estimates of AGB,with the best predictor of AGB varying among different *** AGB of all the five ecosystems was estimated together using a simple linear model,VIUPD showed the lowest prediction error among the eight vegetation *** regression models containing dummy variables predicted AGB with higher accuracy than the simple models,which could be attributed to the dummy variables accounting for the effects of ecosystem type on the relationship between AGB and vegetation index(VI).These results suggest that VIUPD is the best predictor of AGB among simple regression ***,both VIUPD and the soil-adjusted VI could provide accurate estimates of AGB with d

关键词： biomass estimation dummy variable hyperspectral remote sensing Tibetan Plateau regression analysis vegetation index VIUPD