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The noise matrix theory of two-port network--The noise analysis of a feedback amplifier

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Chinese Science Bulletin 1997年第19期42卷 1665-1669页

作者： Dai, YS Qian, zh Li, YQ Department of Electronics Engineering Jilin University of Technolsgy Changchun China

ThE low-noise preamplifier, as one of the major circuits in signal detection system, consists ofthe low noise amplifier and the feedback network. The low noise amplifier design aims both tocalculate the optimal source impedance and minimum noise figure, and to compare the noiseperformance and other characteristics of variant circuits and components. The conventional ap-proach to noise analysis of an electronic circuit is to calculate the output noise power of the

关键词： two-port network noise spectral density matrix feedback amplifier.

Lowered testosterone in male obesity： mechanisms, morbidity and management

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Asian Journal of Andrology 2014年第2期16卷 223-231,I0008页

作者： Mark ng Tang Fui Department of Medicine Austin health University of Melbourne Melbourne Department of Endocrinology Austin Health Melbourne Victoria Australia

With increasing modernization and urbanization of Asia, much of the future focus of the obesity epidemic will be in the Asian region. Low testosterone levels are frequently encountered in obese men who do not otherwise have a recognizable hypothalamic-pituitary-testicular （hPT） axis pathology. Moderate obesity predominantly decreases total testosterone due to insulin resistance-associated reductions in sex hormone binding globulin. More severe obesity is additionally associated with reductions in free testosterone levels due to suppression of the hPT axis. Low testosterone by itself leads to increasing adiposity, creating a self-perpetuating cycle of metabolic complications. Obesity-associated hypotestosteronemia is a functional, non-permanent state, which can be reversible, but this requires substantial weight loss. While testosterone treatment can lead to moderate reductions in fat mass, obesity by itself, in the absence of symptomatic androgen deficiency, is not an established indication for testosterone therapy. Testosterone therapy may lead to a worsening of untreated sleep apnea and compromise fertility. Whether testosterone therapy augments diet- and exercise-induced weight loss requires evaluation in adequately designed randomized controlled clinical trials.

关键词： androgens hypogonadism obesity testosterone weight loss

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中国城镇居民收入和消费的协整分析

消费经济 2005年第2期21卷 16-19页

作者：张继海臧旭恒山东大学经济学院山东济南250100

本文利用误差修正模型对中国城镇居民收入和消费进行协整分析。通过协整分析实证分析了中国城镇居民消费和收入之间的短期波动和长期均衡关系。实证分析的结果表明中国城镇居民家庭实际收入和实际消费之间存在长期的协整关系,当期收入... 详细信息

本文利用误差修正模型对中国城镇居民收入和消费进行协整分析。通过协整分析实证分析了中国城镇居民消费和收入之间的短期波动和长期均衡关系。实证分析的结果表明中国城镇居民家庭实际收入和实际消费之间存在长期的协整关系,当期收入和长期均衡对居民消费都具有较强的制约作用。在长期中,收入增长是制约居民消费增长的重要因素。

关键词：中国城镇居民收入消费需求消费者消费水平

STUDIES　ON　ThE　NON－ISOThERMAL　KINETICS　OF　ThERMAL　DECOMPOSITIONS　OF　ThE　COMPLEXES　OF　Cd（II）WITh　O－VANILLIN　ThIOSEMICARBAZONE　AND　IRON（III）WITh　2－［（O－hYDROXYBENZYLIDENE）AMINO］PhENOL　AND　PYRIDINE

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Chinese Chemical Letters 1995年第7期6卷 637-640页

作者： hu, QP Cui, XG Yang, zh Shandong Univ Dept Chem Jinan 250100 Peoples R China Shandong Univ Inst Crystal Mat Jinan 250100 Peoples R China

The thermal decompositions of the complex of Cd(II) with o-vanillin thiosemicarbazone (complex 1) and the mixed ligand complex of iron (III) with 2-[(o-hydroxybenzylidene)amino] phenol and pyridine (complex 2) and their non-isothermal kinetics have been studied by TG and DTG *** non-isothermal kinetic data were analyzed and the kinetic parameters for the first and second steps of the thermal decompositions were evaluated by twodifferent methods -- differential and integral methods. Their kinetic equatiolls were obtained.

关键词： III IRON ThIOSEMICARBAZONE AMINO AND

Computer Simulation of Two Component Dense Plasma by Molecular Dynamics Method

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Communications in Computational Physics 2014年第4期15卷 1159-1166页

作者： zh.A.Moldabekov T.S.Ramazanov IETP Al-Farabi Kazakh National University71 Al Farabi av.Almaty050040 Kazakhstan

In the present work two component dense semiclassical plasma of protons and electrons is *** and electrodynamic properties of the plasma by molecular dynamic simulation are *** these purposes semiclassical interparticle potential which takes into account quantum mechanical diffraction and symmetry effects is *** considered range of density of plasma is n=1022cm^(−3)to n=1024cm^(−3).Fluctuations and dynamic dielectric functions were calculated using velocity autocorrelation functions.

关键词： Molecular dynamic simulation dense semiclassical plasma semiclassical interparticle potential

On compact splitting complex submanifolds of quotients of bounded symmetric domains

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Science China Mathematics 2017年第6期60卷 1057-1076页

作者： MOK ngaiming ng SuiChung Department of Mathematics The University of Hong Kong Department of Mathematics Shanghai Key Laboratory of PMMPEast China Normal University

We study compact complex submanifolds S of quotient manifolds X =Ω/F of irreducible bounded symmetric domains by torsion free discrete lattices of automorphisms, and we are interested in the characterization of the totally geodesic submanifolds among compact splitting complex submanifolds S C X, i.e., under the assumption that the tangent sequence over S splits holomorphically. We prove results of two types. The first type of results concerns S C X which are characteristic complex submanifolds, i.e., embedding Ω as an open subset of its compact dual manifold M by means of the Borel embedding, the non-zero （1, 0）-vectors tangent to S lift under a local inverse of the universal covering map π → X to minimal rational tangents of M. We prove that a compact characteristic complex submanifold S C X is necessarily totally geodesic whenever S is a splitting complex submanifold. Our proof generalizes the case of the characterization of totally geodesic complex submanifolds of quotients of the complex unit ball B^n obtained by Mok （2005）. The proof given here is however new and it is based on a monotonic property of curvatures of hermitian holomorphic vector subbundles of hermitian holomorphic vector bundles and on exploiting the splitting of the tangent sequence to identify the holomorphic tangent bundle Ts as a quotient bundle rather than as a subbundle of the restriction of the holomorphic tangent bundle Tx to S. The second type of results concerns characterization of total geodesic submanifolds among compact splitting complex submanifolds S C X deduced from the results of Aubin （1978） and Yau （1978） which imply the existence of Kahler-Einstein metrics on S C X. We prove that compact s- plitting complex submanifolds S C X of sufticiently large dimension （depending on ） are necessarily totally geodesic. The proof relies on the hermitian-Einstein property of holomorphic vector bundles associated to TS, which implies that endomorphisms of such bundles are parallel, and the co

关键词： bounded symmetric domains tangent sequence splitting complex submanifolds varieties of minimal rational tangents K/ihler-Einstein metrics

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中国有色金属学会会刊：英文版 2001年第6期11卷 843-846页

作者： Yan, hG Chen, zh Kang, ZT Chen, G hunag, PY hunan Univ Sch Mat Sci & Engn Changsha 410082 Peoples R China Cent S Univ Dept Mat Sci & Engn Changsha 410083 Peoples R China

The phase formation regularities in nanometer powders of ternary alloys prepared by gas evaporation process with induction current as the heating source were investigated. Al-Cu-Mn and Al-Cu-Cr were chosen as the samples in this study. The experimental results show that the necessary conditions for forming ternary compound phases in a ternary alloy nanometer powder are that they must be able to form in a conventional bulk alloy. To obtain a ternary compound phase in nanometer powders, composition of the master alloy must be in a certain range. Changing the composition of the master alloy and evaporation temperature can control the kinds of the phases and their relative amount in the alloy nanometer powders. In present study, AlMn, Al8Mn5 and AlCu2Mn phases formed in as-prepared nanometer powders of Al-Cu-Mn alloy, and the highest relative amount of AlCu2Mn phase is about 99%. In nanometer powders of Al-Cu-Cr alloy,Cu9Al4, Al2Cu3, AlCr2 and Al13Cr2 phases formed without any ternary compound phase.

关键词： nanometer powder gas evaporation alloy powder

MEChANICAL PROPERTIES AND MICROSTRUCTURES OF Ti(C,N) BASED CERMETS

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中国有色金属学会会刊：英文版 1996年第4期6卷 117-121页

作者： Liu, N hu, zh Cui, K Liu, CL ANhUI INST TEChNOL DEPT MAT SCI & ENGNHEFEI 230069PEOPLES R CHINA hUAzh.ng UNIV SCI & TEChNOL WUHAN 430074PEOPLES R CHINA BEIJIng GEN RES INST IRON & STEEL BEIJING 100081PEOPLES R CHINA

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉ... 详细信息

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，ＡｎｈｕｉＩｎｓｔｉｌｕｔｅ...

关键词： Ti(C,N) based cermets mechanical properties microstructure

Dysfunction of synaptic endocytic trafficking in Parkinson's disease

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Neural Regeneration Research 2024年第12期19卷 2649-2660页

作者： Xin Yi ng Mian Cao Programme in Neuroscience and Behavioural Disorders Duke-NUS Medical SchoolSingaporeSingapore Department of Physiology National University of SingaporeSingaporeSingapore

Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the *** precise reasons behind the specific degeneration of these dopamine neurons remain largely *** investigations have identified over 20 causative PARK genes and 90 genomic risk loci associated with both familial and sporadic Parkinson's ***,several of these genes are linked to the synaptic vesicle recycling process,particularly the clathrinmediated endocytosis *** suggests that impaired synaptic vesicle recycling might represent an early feature of Parkinson's disease,followed by axonal degeneration and the eventual loss of dopamine cell bodies in the midbrain via a"dying back"***,several new animal and cellular models with Parkinson's disease-linked mutations affecting the endocytic pathway have been created and extensively *** models faithfully recapitulate certain Parkinson's disease-like features at the animal,circuit,and cellular levels,and exhibit defects in synaptic membrane trafficking,further supporting the findings from human genetics and clinical *** this review,we will first summarize the cellular and molecular findings from the models of two Parkinson's disease-linked clathrin uncoating proteins:auxilin(DNAJC6/PARK19)and synaptojanin 1(SYNJ1/PARK20).The mouse models carrying these two PARK gene mutations phenocopy each other with specific dopamine terminal pathology and display a potent synergistic ***,we will delve into the involvement of several clathrin-mediated endocytosis-related proteins(GAK,endophilin A1,SAC2/INPP5 F,synaptotagmin-11),identified as Parkinson's disease risk factors through genome-wide association studies,in Parkinson's disease *** will also explore the direct or indirect roles of some common Parkinson's disease-linked proteins(alpha-synuclein(PARK1/4),Parkin(PARK2),and LRRK2(PARK

关键词： autophagy auxilin/PARK19 clathrin-mediated endocytosis dopamine neurons neurodegeneration nigrostriatal pathway Parkinson's disease synaptic vesicle recycling synaptojanin1/PARK20