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Supplemental Chromium Picolinate Promotes Growth of Broiler Chickens by Enhancing Insulin Receptor Gene Expression

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journal of Animal Science and Biotechnology 2010年第1期1卷 7-14页

作者： Z.Z.Liu G.Q.Wu j.X.zheng j.y.An N.yang G.y.Xu CollegeofAnimalScienceandTechnologv.CllinaAzriculturalU11iversity Beijing100193.China

Chromium has been recognized for dec- ades as a nutritional factor that promotes the growth of broiler chickens, but the molecular mechanism is still not clearly understood. The present study was de- signed to investigate the physiological and molecular mechanisms of the effects of supplemental chromium picolinate on the growth of broiler chickens. A total of 144 21-day-old Arbor Acres male broiler chicks were randomly divided into a control and an experimental group. The control group was fed a basal diet, and the experimental group was fed the same basal diet sup- plemented with 200 μg/kg chromium picolinate. The experiment lasted for three weeks from day 28 to 42 of the birds.. Supplementation with 200 μg/kg chro- mium picolinate significantly increased body weight （ P 〈 0.05）. Serum insulin levels in chickens of the experimental group were increased significantly （P 〈0. 05 ）, whereas serum glucose concentrations were decreased （P 〈 0.05）. No significant changes were observed in serum lipid profiles in chickens fed the di- et supplemented with chromium picolinate. Gene ex- pression levels of the insulin receptor （IR） and insu- lin receptor substrate 1 （IRS-1）, two pivotal compo- nents of the insulin signaling pathway, were also in- vestigated using Real-time quantitative PCR. IR ex- pression was significantly （P 〈 0.05） increased fol- lowing chromium supplementation. Therefore, supple- mental chromium picolinate had a beneficial effect on the growth of broilers. In agreement with observations in mammals, chromium might exert its effect via po- tentiating insulin action, and ultimately by stimulating anabolism without altering body composition in chick- ens.

关键词： broiler chickens chromium growth IR IRS-1

Mean Platelet volume and platelet size deviation width have not enough predictive efficiency for diagnosis of bone marrow failure in thrombocytopenic patients

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Mean Platelet volume and platelet size deviation width have ...

“北半球千年尺度气候高分辨率数据集研制及可靠性研究”项目数据集集合出版

2008年浙江省检验医学学术年会

作者： Z.j.zheng,y.j.Ma,R.L.Xu,y.P.Hu,S.H.Zhuang Department of Laboratory Medicine,jinhua Municipal Central Hospital,jinhua 321000, Zhejiang,China

Introduction Information on platelet size is widely available to clinicians as part of the data provided in the full blood count .Whilst data on the size(mean cell volume)and deviation width(RDW)of red blood cells are universally used for investigation of anaemia,the diagnostic value of information on platelet size and deviation width in

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来源： cnki会议评论

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全球变化数据学报（中英文） 2022年第3期6卷 327-329,V0327-V0329页

作者：郑景云中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101

2017年国家重点研发计划“全球变化及应对”专项中批准设立了“北半球千年尺度气候高分辨率数据集研制及可靠性研究”项目。作者作为该项目的负责人组织研发和汇集了一系列数据集。其中,首批选出12个数据集及其数据论文关联出版。

关键词：全球变化项目数据集北半球千年尺度集合出版

Gene therapy for spinal muscular atrophy:perspectives on the possibility of optimizing SMN1 delivery to correct all neurological and systemic perturbations

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Neural Regeneration Research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brown Rafael j.yáñez-Muñoz Heidi R.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK Wolfson Center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(Lefebvre et al.,1995).This,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

华南地区300年来逐年冷冬指数数据集(1710-2009)

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全球变化数据学报（中英文） 2018年第2期2卷 163-167,286-290页

作者：丁玲玲郑景云湖北文理学院资源环境与旅游学院襄阳441053 中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101

在对华南地区(包括广东、广西、福建和海南等省区)历史文献资料(包括清代雨雪分寸档案和地方志类汇编资料)和仪器观测记录(中国地面气候资料日值数据集和分月中国地面气象记录)汇编基础上,基于鹿世瑾等(1990)的华南地区冬季冷暖分级标准... 详细信息

在对华南地区(包括广东、广西、福建和海南等省区)历史文献资料(包括清代雨雪分寸档案和地方志类汇编资料)和仪器观测记录(中国地面气候资料日值数据集和分月中国地面气象记录)汇编基础上,基于鹿世瑾等(1990)的华南地区冬季冷暖分级标准,建立华南地区冷冬指数重建标准,即1级为冷;2级为寒;3级为大寒;4级为特寒。根据记录发生地区的霜雪冰冻状况,确定华南地区冬季的寒冷程度,对缺失年份进行了数据差补,以此研发了华南地区300年来逐年冷冬指数数据集(1710-2009)。数据结果表明,在300年中,大多数年份(145年)为寒(2级),占比48.33%;其次为大寒(3级,98年),占比32.67%;50年冷冬指数为冷(1级),占比16.67%;仅7年为特寒(4级),占比2.33%。该数据集存储为.xlsx格式,数据量为13.7 KB。

关键词：华南地区冷冬指数过去300年

A modified multi-objective particle swarm optimization approach and its application to the design of a deepwater composite riser

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Acta Mechanica Sinica 2018年第2期34卷 275-284页

作者： y.zheng j.Chen Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074China

A modified multi-objective particle swarm optimization method is proposed for obtaining Pareto-optimal solutions effectively. Different from traditional multiobjective particle swarm optimization methods, Kriging meta-models and the trapezoid index are introduced and integrated with the traditional one. Kriging meta-models are built to match expensive or black-box functions. By applying Kriging meta-models, function evaluation numbers are decreased and the boundary Pareto-optimal solutions are identified rapidly. For bi-objective optimization problems, the trapezoid index is calculated as the sum of the trapezoid’s area formed by the Pareto-optimal solutions and one objective axis. It can serve as a measure whether the Pareto-optimal solutions converge to the Pareto front. Illustrative examples indicate that to obtain Paretooptimal solutions, the method proposed needs fewer function evaluations than the traditional multi-objective particle swarm optimization method and the non-dominated sorting genetic algorithm II method, and both the accuracy and the computational efficiency are improved. The proposed method is also applied to the design of a deepwater composite riser example in which the structural performances are calculated by numerical analysis. The design aim was to enhance the tension strength and minimize the cost. Under the buckling constraint, the optimal trade-off of tensile strength and material volume is obtained. The results demonstrated that the proposed method can effec tively deal with multi-objective optimizations with black-box functions.

关键词： Multi-objective particle swarm optimization Kriging meta-model Trapezoid index Deepwater composite riser

Comparative in vitro Study on Pure Metals(Fe,Mn,Mg,Zn and W) as Biodegradable Metals

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journal of Materials Science & Technology 2013年第7期29卷 619-627页

作者： j.Cheng B.Liu y.H.Wu y.F.zheng Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary StudiesPeking University State Key Laboratory for Turbulence and Complex System and Department of Materials Science and Engineering College of EngineeringPeking University

Five pure metals including Fe, Mn, Mg, Zn and W have been investigated on their corrosion behavior and in vitro biocompatibility by electrochemical measurement, static immersion test, contact angle measurement, cytotoxicity and hemocompatibility tests. It is found that the sequence of corrosion rate of five metals in Hank＇s solution from high to low is： Mg 〉 Fe 〉 Zn 〉 Mn 〉 W. Fe, Mg and W show no cytotoxicity to L929 and ECV304 cells, Mn induces significant cytotoxicity to both L929 and ECV304 cells, and Zn has almost no inhibition effect on the metabolic activities of ECV304 while largely reduces the cell viability of L929 cells. The hemolysis percentage of five pure metals is lower than 5% except for Mg and platelets adhered on Zn has been activated and pseudopodia-like structures can be observed while platelets on the other four metals keep normal.

关键词： Biodegradable metals Cytotoxicity Corrosion Biocompatibflity

A Comparative in vitro Study on Biomedical Zr-2.5X(X=Nb,Sn) Alloys

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journal of Materials Science & Technology 2014年第4期30卷 299-306页

作者： F.y.Zhou K.j.Qiu D.Bian y.F.zheng j.P.Lin Centre for Biomedical Materials and Engineering Harbin Engineering University Department of Materials Science and Engineering College of EngineeringPeking University State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Nb and Sn are major alloying elements in Zr alloys. In this study, the microstructure, mechanical properties, corrosion behavior, cytocompatibility and magnetic resonance imaging （MRI） compatibility of Zr-2.5X （X = Nb, Sn） alloys for biomedical application are comparatively investigated. It is found that Zr-2.5Nb alloy has a duplex structure of ~ and ~ phase and Zr-2.5Sn alloy is composed of α phase. Both separate addition of Nb and Sn can strengthen Zr but Nb is more effective in strengthening Zr than Sn. The studied Zr-2.5X （X = Nb, Sn） alloys show improved corrosion resistance compared to pure Zr as indicted by the decreased corrosion current density. The alloying addition of Nb enhances the pitting resistance of Zr, whereas the addition of Sn decreases the pitting resistance of Zr. The extracts of Zr-2.5X alloys produce no significant deleterious effect on fibroblast cells （L-929） and osteoblast-Iike cells （MG 63）, indicating good in vitro cytocompatibility. The Zr-2.5X （X = Nb, Sn） alloys show decreased magnetic susceptibility compared to pure Zr and their magnetic susceptibility is far lower than that of pure Ti and Ti-6AI-4V alloy. Based on these facts, Zr-2.5Nb alloy is more suitable for implant material than Zr-2.5Sn alloy. Sn is not suitable as individual alloying addition for Zr because Sn addition decreases the pitting resistance in physiological solution.

关键词： Zr alloys Mechanical properties Corrosion resistance Cytocompatibility Magnetic susceptibility

An efficient SPH methodology for modelling mechanical characteristics of particulate composites

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Defence Technology（防务技术） 2021年第1期17卷 135-146页

作者： Z.j.zheng S.Kulasegaram P.Chen y.Q.Chen Department of Mechanics College of Mechanical EngineeringChongqing University of TechnologyChongqing400054China Institute of Applied and Computational Mechanics Cardiff School of EngineeringCardiff UniversityQueen’s BuildingsThe ParadeCardiffCF243AAWalesUK Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing100871China

Particulate composites are one of the widely used materials in producing numerous state-of-the-art components in biomedical,automobile,aerospace including defence *** of modelling techniques have been adopted in the past to model mechanical behaviour of particulate *** to their favourable properties,particle-based methods provide a convenient platform to model failure or fracture of these *** particle hydrodynamics(SPH)is one of such methods which demonstrate excellent potential for modelling failure or fracture of particulate composites in a Lagrangian *** of the major challenges in using SPH method for modelling composite materials depends on accurate and efficient way to treat interface and boundary *** this paper,a masterslave method based multi-freedom constraints is proposed to impose essential boundary conditions and interfacial displacement constraints in modelling mechanical behaviour of composite materials using SPH *** proposed methodology enforces the above constraints more accurately and requires only smaller condition number for system stiffness matrix than the procedures based on typical penalty function approach.A minimum cut-off value-based error criteria is employed to improve the computational efficiency of the proposed *** addition,the proposed method is further enhanced by adopting a modified numerical interpolation scheme along the boundary to increase the accuracy and computational *** numerical examples demonstrate that the proposed master-slave approach yields better accuracy in enforcing displacement constraints and requires approximately the same computational time as that of penalty method.

关键词： Particulate composites SPH Essential boundary condition Multi-point constraints Master-slave method