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The Separation of Powers from Functions and the Establishment of a New Structure of Management and Operation of State-owned Assets
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作者 Zhou Li-qun Ph. D. of Economics. Associate Professor of Institute of Economics of NANKAI UNIVERSITY. Deputy Dean of College of Economics, NANKAI UNIVERSITY 《南开经济研究》 CSSCI 北大核心 1994年第S3期13-18,共6页
The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agemen... The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agement of state-owned assets,and the improvement of the operating bene- 展开更多
关键词 The Separation of Powers from functions and the Establishment of a New structure of Management and Operation of State-owned Assets
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A study on deep structure using teleseismic receiver function in Western Yunnan 被引量:18
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作者 贺传松 王椿镛 吴建平 《地震学报》 CSCD 北大核心 2004年第3期238-246,共9页
s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, i... s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, it is one of the seismically active areas. In the paper, the teleseismic records were selected from 16 national, local and mo-bile stations, including 4 very-wide-band mobile stations of PASSCAL. And nearly 2 000 receiver functions were extracted. Two measuring lines are 650 km and 450 km, respectively and across some major tectonic units in Western Yunnan. It is indicated that Nujiang might be a seam characterized by underthrusting. The western and eastern boundaries of Sichuan-Yunnan rhombus block, i.e., Honghe and Xiaojiang faults, might be an erection seam or collision belt. Panxi tectonic zone still has the characteristics of continental rift valley, that is, the surface is hollow and the upper mantle is upwarping. The tectonic situation in Western Yunnan is of certain regulation with the interlacing distribution of orogenic zone and seam. The crustal thickness decreases gradually from the north to the south and the S wave velocity is globally lower here. 展开更多
关键词 接收函数 反演 S波速度结构 构造关系
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Electronic structure and flotability of gold-bearing pyrite:A density functional theory study 被引量:2
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作者 LIU Dan WANG Yi-jie +1 位作者 XIAN Yong-jun WEN Shu-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2288-2293,共6页
Various incorporation of Au in pyrite and its effects on the geometrical structure,electronic structure and flotability of pyrite were theoretically investigated and fully discussed by performing density functional th... Various incorporation of Au in pyrite and its effects on the geometrical structure,electronic structure and flotability of pyrite were theoretically investigated and fully discussed by performing density functional theory(DFT).The calculated incorporation energy shows that gold would most likely exist in pyrite via incorporating into interstitial lattice sites in the absence of As impurity.As a result of incorporated Au,the covalence levels of the S—Fe and S—S bonds are changed,and the tonicity of Au—S bonds and antibonding of Au—Fe bonds are found to form in the pyrite,which would change the natural flotability of pyrite.The Au impurity energy levels are introduced into the energy band and result in the transformation of pyrite semiconductivity type.The calculated band-gap value suggests that the incorporated Au significantly decreases pyrite semiconductivity level,which enhances the formation and the adsorption stability of dixanthogen during pyrite flotation.The DOS results reveal that the stability and depression difficulty level of pyrites increases in the following order:Fe_(32)S_(63)As<Fe_(32)S_(64)<Fe_(32)S_(63)As Au<Fe_(32)S_(64)Au. 展开更多
关键词 PYRITE GOLD DENSITY functionAL theory electronic structure flotability
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Characteristics of soil microbial community functional and structure diversity with coverage of Solidago Canadensis L 被引量:13
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作者 廖敏 谢晓梅 +2 位作者 彭英 柴娟娟 陈娜 《Journal of Central South University》 SCIE EI CAS 2013年第3期749-756,共8页
The relationship between Solidago canadensis L. invasion and soil microbial community diversity including functional and structure diversities was studied across the invasive gradients varying from 0 to 40%, 80%, and ... The relationship between Solidago canadensis L. invasion and soil microbial community diversity including functional and structure diversities was studied across the invasive gradients varying from 0 to 40%, 80%, and 100% coverage of Solidago canadensis L. using sole carbon source utilization profiles analyses, principle component analysis (PCA) and phospholipid fatty acids (PLFA) profiles analyses. The results show the characteristics of soil microbial community functional and structure diversity in invaded soils strongly changed by Solidago canadensis L. invasion. Solidago canadensis L. invasion tended to result in higher substrate richness, and functional diversity. As compared to the native and ecotones, average utilization of specific substrate guilds of soil microbe was the highest in Solidago canadensis L. monoculture. Soil microbial functional diversity in Solidago canadensis L. monoculture was distinctly separated from the native area and the ecotones. Aerobic bacteria, fungi and actinomycetes population significantly increased but anaerobic bacteria decreased in the soil with Solidago canadensis L. monoculture. The ratio of cyl9:0 to 18:1 co7 gradually declined but mono/sat and fung/bact PLFAs increased when Solidago canadensis L. became more dominant. The microbial community composition clearly separated the native soil from the invaded soils by PCA analysis, especially 18: lco7c, 16: lco7t, 16: lco5c and 18:2co6, 9 were present in higher concentrations for exotic soil. In conclusion, Solidago canadensis L. invasion could create better soil conditions by improving soil microbial community structure and functional diversity, which in turn was more conducive to the growth ofSolidago canadensis L. 展开更多
关键词 sole carbon source utilization phospholipid fatty acids structure diversity functional diversity Solidago canadensis L.
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Effect of salt solutions on chain structure of partially hydrolyzed polyacrylamide 被引量:2
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作者 张青 周吉生 +2 位作者 翟永爱 刘凤岐 高歌 《Journal of Central South University》 SCIE EI CAS 2008年第S1期80-83,共4页
The effect of salt solutions(NaCl,Na2SO4 and CaCl2) on the conformational properties of partially hydrolyzed polyacrylamide(HPAM) was investigated by using static laser light scattering(SLLS).The special interaction b... The effect of salt solutions(NaCl,Na2SO4 and CaCl2) on the conformational properties of partially hydrolyzed polyacrylamide(HPAM) was investigated by using static laser light scattering(SLLS).The special interaction between CaCl2 solution and HPAM was also researched.Experimental results show that the chain structure of HPAM is interrelated with the charge density,the kind and the concentration of salt solutions.The mean-square radius of gyration(Rz) and the second virial coefficient(A2) of HPAM decrease with increasing concentration of salt solutions,and the salt effect tends towards the maximum when the concentration of salt solution is increased to some amount. 展开更多
关键词 PARTIALLY hydrolyzed polyacrylamide(HPAM) SALT EFFECT chain structure static laser light scattering(SLLS)
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Phase composition, transition and structure stability of functionally graded cemented carbide with dual phase structure 被引量:2
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作者 张立 陈述 +3 位作者 熊湘君 贺跃辉 黄伯云 张传福 《Journal of Central South University of Technology》 EI 2007年第2期149-152,共4页
The phase composition, phase transition and phase structure transformation of the wire-cut section of functionally graded WC-Co cemented carbide with dual phase structure were investigated by XRD phase analysis. It is... The phase composition, phase transition and phase structure transformation of the wire-cut section of functionally graded WC-Co cemented carbide with dual phase structure were investigated by XRD phase analysis. It is shown that the composition of η phase in the core zone is Co_3W_3C (M_6 C type). The structure of cobalt based solid solution binder phase is fcc type. At the cooling stage of the sintering process, the phase transition of η phase, i.e. M_6C→M_12C and the martensitic phase transition of the cobalt based solid solution binder phase, i.e. fcc→hcp are suppressed, which facilitates the strengthening of the alloy. Because the instantaneous temperature of the discharge channel is as high as 10 000 ℃ during the wire cutting process, the processed surface is oxidized. Nevertheless, the oxide layer thickness is in micro grade. In the oxide film, η phase is decomposed into W_2C and CoO, and cobalt based solid solution binder is selectively oxidized, while WC remains stable due to the existence of carbon containing liquid organic cutting medium. 展开更多
关键词 cemented carbide dual phase structure functionally graded material phase identification fracture toughness testing
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Density functional investigation on structural and electronic properties of small bimetallic Pb_(n)Ag_(n)(n=2–12)clusters 被引量:1
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作者 LI Gao-feng WANG Jia-ju +4 位作者 CHEN Xiu-min YANG Hong-wei YANG Bin XU Bao-qiang LIU Da-chun 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期772-782,共11页
Structural and electronic properties of Pb_(n)Ag_(n)(n=2–12)clusters were investigated by density functional theory with generalized gradient approximation at BLYP level in DMol3 program package.The optimized bimetal... Structural and electronic properties of Pb_(n)Ag_(n)(n=2–12)clusters were investigated by density functional theory with generalized gradient approximation at BLYP level in DMol3 program package.The optimized bimetallic Pb_(n)Ag_(n)(n=2–12)clusters were viewed as the initial structures,then,those were calculated by ab initio molecular dynamics(AIMD)to search possible global minimum energy structures of Pb_(n)Ag_(n)clusters,finally,the ground state structures of Pb_(n)Ag_(n)(n=2–12)clusters were achieved.According to the structural evolution of lowest energy structures,Ag atoms prefer gather in the central sites while Pb atoms prefer external positions in Pb_(n)Ag_(n)(n=2–12)clusters,which is in excellent agreement with experimental results from literature and the application in metallurgy.The average binding energies,HOMO-LUMO gaps,vertical ionization potentials,vertical electron affinities,chemical hardnessη,HOMO orbits,LUMO orbits and density of states of Pb_(n)Ag_(n)(n=2–12)clusters were calculated.The results indicate that the values of HOMO-LUMO gaps,vertical ionization potentials,vertical electron affinities and chemical hardnessηshow obvious odd-even oscillations when n≤5,Pb_(n)Ag_(n)(n=2–12)clusters become less chemically stable and show insulator-to-metal transition with the variation of cluster size n,Pb_(n)Ag_(n)(n≥9)cluster are good candidates to study the properties of PbAg alloys.Those can be well explained by the density of states(DOS)distributions of Pb atoms and Ag atoms between–0.5 Ha and 0.25 Ha in Pb_(n)Ag_(n)(n=2–12)clusters. 展开更多
关键词 density functional theory Pb_(n)Ag_(n)(n=2–12)clusters ab initio molecular dynamics ground state structure
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Density functional theory study on the structure and properties of Si3N4 clusters 被引量:3
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作者 ZHANG Cai-rong ZHANG Bi-xia +2 位作者 CHEN Yu-hong LI Wei-xue XU Guang-ji 《原子与分子物理学报》 CAS CSCD 北大核心 2006年第B04期171-174,共4页
关键词 硅氮化物 结构 特性 密度函数理论
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Effects of Aluminum Trichloride on Structure and Function of Kidney in Chickens
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作者 Zhang Ji-hong Luo Ji-long +4 位作者 Yu Hong-xiang Bai Chong-sheng Han Yan-fei Xia Shi-liang Li Yan-fei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第3期83-86,共4页
To investigate the effects of aluminum trichloride (AlCl3) on renal structure and function in chickens, the chickens were injected continuously with different gradient AlCl3 for 60 days to establish sub-chronic alum... To investigate the effects of aluminum trichloride (AlCl3) on renal structure and function in chickens, the chickens were injected continuously with different gradient AlCl3 for 60 days to establish sub-chronic aluminum (Al) intoxication model. The AI concentration in serum and kidney, contents of creatinine (Cr) and blood urea nitrogen (BUN) in serum were detected, and the renal structure was also observed by optical microscope. The results showed that the A1 concentration in serum and kidney, the contents of Cr and BUN in serum were significantly higher in Al-treated chickens than those in the control group (P〈0.05; P〈0.01) and there was an AlCl3 dose-depended manner. Histopathologically, in the low dose group, acinus renis swelled mildly and there were no apparent pathological changes in nephric tubule and proximal convoluted tubule. In the middle and high dose group, acinus renis swelled, glomerular cells increased, nephric tubule cloudy swelled, and epithelial cells of proximal convoluted tubule swelled. The results indicated that sub-chronic Al exposure impaired the renal structure and function in chickens. 展开更多
关键词 aluminum trichloride structure and function KIDNEY CHICKEN
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Functional microbiomics reveals branched-chain amino acids depletion for alleviation of insulin resistance by berberine
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作者 YUE Shi-jun WANG Wen-xiao +1 位作者 YAN Dan TANG Yu-ping 《中国药理学与毒理学杂志》 CAS 北大核心 2019年第9期738-738,共1页
Increased circulating branched-chain amino acids(BCAAs)have been involved in the pathogenesis of obesity and insulin resistance.However,evidence relating berberine(BBR),gut microbiota,BCAAs,and insulin resis⁃tance is ... Increased circulating branched-chain amino acids(BCAAs)have been involved in the pathogenesis of obesity and insulin resistance.However,evidence relating berberine(BBR),gut microbiota,BCAAs,and insulin resis⁃tance is limited.Here,we showed that BBR could effectively rectify steatohepatitis and glucose intolerance in high-fat diet(HFD)-fed mice.BBR reorganized gut microbiota populations under both the normal chow diet(NCD)and HFD.Particu⁃larly,BBR noticeably decreased the relative abundance of BCAA-producing bacteria,including order Clostridiales;fami⁃lies Streptococcaceae,Clostridiaceae,and Prevotellaceae;and genera Streptococcus and Prevotella.Compared with the HFD group,predictive metagenomics indicated a reduction in the proportion of gut microbiota genes involved in BCAA biosynthesis but the enrichment genes for BCAA degradation and transport by BBR treatment.Accordingly,the elevated serum BCAAs of HFD group were significantly decreased by BBR.Furthermore,the Western blotting results implied that BBR could promote the BCAA catabolism in the liver and epididymal white adipose tissues of HFD-fed mice by acti⁃vation of the multienzyme branched-chain α-ketoacid dehydrogenase complex,whereas by inhibition of the phosphoryla⁃tion state of BCKDHA(E1α subunit)and branched-chain α-ketoacid dehydrogenase kinase.The ex vivo assay further confirmed that BBR could increase BCAA catabolism in both AML12 hepatocytes and 3T3-L1 adipocytes.Finally,data from healthy subjects and diabetics confirmed that BBR could improve glycemic control and modulate circulating BCAAs.Besides,functional microbiomics integrated high-throughput microbial genomics,metabolomics and molecular biotechnology has also been successfully applied to reveal the anti-obesity mechanism of hydroxysafflor yellow A. 展开更多
关键词 functional microbiomics BERBERINE branched-chain amino acids insulin resistance
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Structure/function relationships in cellulolytic enzymes
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作者 Marc Claeyssens 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期432-432,共1页
Cellulose and hemicellulose (mostly xylan), together with lignin, are the major polymeric constituents of plant cell walls and from the largest reservoir of fixed carbon in nature. The enzymatic hydrolysis of polymeri... Cellulose and hemicellulose (mostly xylan), together with lignin, are the major polymeric constituents of plant cell walls and from the largest reservoir of fixed carbon in nature. The enzymatic hydrolysis of polymeric substances by extracellular enzymes, such as cellulases, hemicellulases and laccases, is preferred to chemical depolymerisation to avoid the production of toxic by-products and waste that are expensive to treat. The monosaccharides released through enzymatic hydrolysis can subsequently be microbially converted to commercial commodities, such as bio-ethanol (fuel extender) or microbial protein as feed supplements. The individual depolymerisering enzymes used, such as cellulases, xylanases and laccases, also have industrial application in (i) biobleaching in the paper and pulp industry, (ii) improvement of animal feed (poultry and ruminants) digestibility in feed industries, and (iii) dough rheology and bread volume in the baking process, and beer viscosity and filtration velocity during brewing. The cloning of the genes, coding for several xylan degrading enzymes, and their expression in Baker’s yeast (Saccharomyces cerevisiae) and filamentous fungi (Aspergillus species) opened the possibility to study the pure enzymes, without contaminating activity. Trichoderma reesei produces several of these enzymes and detailed information on their specificity, synergies and structure/activity relationships is known. An overview will be presented. 展开更多
关键词 纤维素分解酶 结构 功能 木质纤维素 协同作用
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比较4种应用于薄膜与管道的聚乙烯树脂的链结构特点 被引量:1
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作者 高宇新 刘巍 +5 位作者 李瑞 潘艳雄 王登飞 张茗郡 何书艳 姬相玲 《应用化学》 北大核心 2025年第4期490-498,共9页
聚乙烯(PE)是目前世界范围内应用广泛的高分子材料,由乙烯与α-烯烃单体聚合而成的共聚物中单体的含量和序列分布等链结构参数对PE的性能和应用有重要影响。采用高温凝胶渗透色谱(HT-GPC)、核磁共振波谱仪(NMR)、差示扫描量热仪(DSC)和... 聚乙烯(PE)是目前世界范围内应用广泛的高分子材料,由乙烯与α-烯烃单体聚合而成的共聚物中单体的含量和序列分布等链结构参数对PE的性能和应用有重要影响。采用高温凝胶渗透色谱(HT-GPC)、核磁共振波谱仪(NMR)、差示扫描量热仪(DSC)和连续自成核退火热分级技术对4种应用于流延膜(CPE)、耐热聚乙烯(PERT)管道、线性低密度聚乙烯(LLDPE)包装和双向拉伸聚乙烯(BOPE)薄膜的乙烯-辛烯共聚物专用树脂进行了链结构的对比研究。分析对比了链结构参数,包括相对分子质量及其分布、共聚单体的摩尔分数、三元组序列分布、平均乙烯和辛烯的序列长度以及平均亚甲基序列长度。结果表明,虽然CPE和PERT均为高密度聚乙烯(HDPE),但PERT的相对分子质量要高得多且相对分子质量分布更宽,这有利于在晶区间形成更多的系带分子,改善PERT管道的耐环境应力开裂、抗冲击和抗慢速裂纹扩展性能;LLDPE和BOPE均为线性低密度聚乙烯,但BOPE中含有更多更长的结晶序列,有利于提高分子链的取向度。 展开更多
关键词 聚乙烯 共聚单体 链结构 序列分布
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制造商过度自信下考虑权力结构的双渠道绿色供应链动态决策 被引量:3
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作者 贡文伟 夏萌 +1 位作者 丁凡 孙立成 《计算机集成制造系统》 北大核心 2025年第2期661-673,共13页
为探究制造商过度自信行为特征和权力结构差异对双渠道绿色供应链成员动态决策的影响,构建制造商主导、零售商主导和双方权力对等3种情况下的微分博弈模型,求解并对比分析各情形下的供应链成员均衡决策和利润。研究表明,当市场环境较差... 为探究制造商过度自信行为特征和权力结构差异对双渠道绿色供应链成员动态决策的影响,构建制造商主导、零售商主导和双方权力对等3种情况下的微分博弈模型,求解并对比分析各情形下的供应链成员均衡决策和利润。研究表明,当市场环境较差时,产品绿色度、销售价格、制造商利润及供应链总利润会随制造商过度自信程度的提高而增加,零售商利润则随之下降,而当市场环境较好时,上述情况均相反;制造商占主导地位会促使自身做出更大的绿色研发努力;供应链成员利润均在自身占主导地位时最高,而供应链总利润在双方权力对等时最高,在零售商主导时最低;制造商的过度自信对自身利润和供应链总利润的影响程度与渠道成员间的权力大小有关。 展开更多
关键词 过度自信 权力结构 双渠道绿色供应链 微分博弈
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不同提取方法对杏仁蛋白结构和功能特性的影响 被引量:1
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作者 李晶晶 罗婷婷 +5 位作者 胡海玥 耿东宇 刘雅萱 王丽娜 杨晨 汪建明 《食品工业科技》 北大核心 2025年第5期72-80,共9页
为提高杏仁蛋白(Almond protein,AP)的利用率,本研究使用等电点沉淀法(Alkaline extraction by isoelectric precipitation,AI)、热碱法(Thermal-alkaline,TA)和盐析法(Salt extraction,SE)提取AP,分别为AIAP、TAAP和SEAP,探究提取方法... 为提高杏仁蛋白(Almond protein,AP)的利用率,本研究使用等电点沉淀法(Alkaline extraction by isoelectric precipitation,AI)、热碱法(Thermal-alkaline,TA)和盐析法(Salt extraction,SE)提取AP,分别为AIAP、TAAP和SEAP,探究提取方法对蛋白质结构和功能特性的影响。结果表明,不同提取方法对AP的结构和功能特性具有显著影响。SEAP的提取率(55.94%)和纯度(88.21%)最高,AIAP的纯度最低(75.06%),TAAP的提取率最低(50.71%)。AIAP表面粗糙且结构疏松,而TAAP和SEAP的结构致密,AIAP的β-折叠含量(44.97%)和表面疏水性高于TAAP和SEAP。相较于TAAP和SEAP,AIAP的持水性和持油性较高。SEAP和TAAP的溶解度显著高于AIAP,且乳化特性和起泡特性较好。本研究为杏仁蛋白在食品工业的应用提供一定的理论参考。 展开更多
关键词 提取方法 杏仁蛋白 结构 功能特性
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生物大模型技术前沿与应用进展 被引量:1
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作者 石金龙 张哲 +2 位作者 戴安琳 林恺 何昆仑 《生理科学进展》 北大核心 2025年第3期235-242,共8页
以基因、转录、蛋白质等生命组学为主体的生物大数据快速积累和以深度学习为代表的人工智能技术迅猛发展,催生出各种类别的生物大模型(biological large models)。复杂的深度学习架构、巨大的参数量和算力需求、以及海量的预训练数据等... 以基因、转录、蛋白质等生命组学为主体的生物大数据快速积累和以深度学习为代表的人工智能技术迅猛发展,催生出各种类别的生物大模型(biological large models)。复杂的深度学习架构、巨大的参数量和算力需求、以及海量的预训练数据等是大模型技术的主要特征。预训练数据类别及参数量一定程度上决定了大模型所具备的能力强弱,而不同的模型架构则可支撑不同类别的下游任务。近两年,围绕DNA/RNA/蛋白质等生物序列与单细胞表达图谱等组学数据分析挖掘、大分子结构预测、新型药物设计和功能机制解析等多种应用场景,涌现了多种通用或专用大模型,展示出其在生物医学研究及转化应用等领域的巨大潜力。本文旨在结合不同类别的生物数据特点和研究应用需求,概述生物数据特征及其用于生物大模型训练的技术方法,并进一步综述现有大模型在生物医学研究及疾病诊疗中的应用进展,为提升生物大模型能力、拓展应用范围提供新的思路。 展开更多
关键词 生物大模型 注意力机制 序列分析 结构预测 功能解读 合成设计
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考虑权力结构和价值不确定性的数据供应链定价策略分析 被引量:1
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作者 扈文秀 刘亚洲 苏欣欣 《计算机工程与应用》 北大核心 2025年第4期310-322,共13页
数字经济时代,数据产品交易已成为引领产业创新和社会进步的关键驱动力,但数据产品的价值不确定性和数据产品市场权力结构的差异给数据产品的定价带来了挑战,无法全面释放数据要素的倍乘价值。为完善数据产品定价策略,促进数据要素流通... 数字经济时代,数据产品交易已成为引领产业创新和社会进步的关键驱动力,但数据产品的价值不确定性和数据产品市场权力结构的差异给数据产品的定价带来了挑战,无法全面释放数据要素的倍乘价值。为完善数据产品定价策略,促进数据要素流通,基于数据产品转化不确定及感知不确定等价值不确定性的特征,综合考虑数据产品终端用户的需求偏好,构建了不同权力结构下数据供应链博弈模型,探讨数据供应链企业的最优决策以及数据产品最优定价策略。研究发现数据产品的最优定价、需求、质量技术水平和推广努力水平受数据产品终端用户的需求偏好、成本系数和价值不确定性的影响,并且在不同权力结构下存在差异。数据供应链企业应根据自身发展灵活改变产品议价,并采取降低数据产品价值不确定性的战略安排,促进数据供应链的健康发展。 展开更多
关键词 数据供应链 数据产品 价值不确定性 定价策略 权力结构
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新时代推动基层矛盾治理现代化的现实样态与实践机理 被引量:1
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作者 赵聚军 庞尚尚 《河海大学学报(哲学社会科学版)》 北大核心 2025年第2期74-85,共12页
基层矛盾治理是国家治理的基础,是基层社会安全稳定和良性运行的“压舱石”。党的十八大以来,在顶层设计的引领下,地方围绕基层矛盾纠纷的预防与化解,进行了大量的实践创新。然而,现有研究多以单案例的形式呈现,未能对基层矛盾治理形成... 基层矛盾治理是国家治理的基础,是基层社会安全稳定和良性运行的“压舱石”。党的十八大以来,在顶层设计的引领下,地方围绕基层矛盾纠纷的预防与化解,进行了大量的实践创新。然而,现有研究多以单案例的形式呈现,未能对基层矛盾治理形成完整的构象与分析。采用程序化扎根方法,基于25个典型案例,构建了一个以“结构-过程-功能”为核心内容的解释框架,力图深入展现新时代推动基层矛盾治理现代化的现实样态与实践机理。研究发现,在问题导向与高位推动的双重动力驱动下,以党政统合为主、多元主体协同参与的基层矛盾治理结构初步成型。在此基础上,沿着“资源-能力-工具”3个维度推进的治理过程,最终有效保障了治理效能释放、社会稳定有序与党政领导力提升等治理功能的实现。为进一步解释新时代基层矛盾治理实践,基于对现实样态的深描,从结构、过程、功能等方面归纳基层矛盾治理的主体间赋能、治理制度化、破除“悬浮化”等深层次实践机理。在全面推动基层矛盾治理现代化的过程中,为保障治理功能的有效发挥,既要继续强化提升党政领导力,也应重视完善各类过程机制。 展开更多
关键词 基层社会安全 矛盾治理 基层治理现代化 结构-过程-功能
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防屈曲支撑-钢筋混凝土框架结构基于韧性的抗震设计方法研究 被引量:1
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作者 马恺泽 李兰欣 +1 位作者 邢国华 陈韵如 《振动与冲击》 北大核心 2025年第7期146-154,共9页
为实现防屈曲支撑-钢筋混凝土(buckling-restrained braced reinforced concrete,BRB-RC)框架结构基于韧性的抗震设计,引入韧性水平量化指标,建立建筑抗震韧性等级的分级,提出利用功能损失控制韧性指标的计算假定,并建立建筑多层级功能... 为实现防屈曲支撑-钢筋混凝土(buckling-restrained braced reinforced concrete,BRB-RC)框架结构基于韧性的抗震设计,引入韧性水平量化指标,建立建筑抗震韧性等级的分级,提出利用功能损失控制韧性指标的计算假定,并建立建筑多层级功能损失量化关系,提出根据建筑功能损失控制构件损伤及工程需求参数的方法。依据BRB-RC框架结构的受力机制,提出其基于韧性的抗震设计方法并建立设计流程。将设计方法应用于一幢5层的BRB-RC框架结构的抗震设计并进行罕遇地震作用下的弹塑性时程分析。分析结果表明,结构的层间位移角和层间剪力分布均满足设计要求,所提出的方法能实现预期的抗震韧性目标。 展开更多
关键词 建筑抗震韧性 防屈曲支撑(BRB) 钢筋混凝土(RC)框架结构 抗震设计 功能损失
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乳骨桥蛋白消化吸收及营养功能研究进展
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作者 张娟 陈曦 +2 位作者 李玉婷 杨续金 陈爱亮 《食品科学》 北大核心 2025年第17期345-357,共13页
乳骨桥蛋白是一种来源于乳汁的多功能磷酸化糖蛋白,在免疫调节、大脑发育与认知功能、肠道健康、骨健康等方面具有重要的营养健康作用,可作为新食品原料用于婴配粉等食品中。本文着重对乳骨桥蛋白的结构特征、消化吸收和营养功能研究进... 乳骨桥蛋白是一种来源于乳汁的多功能磷酸化糖蛋白,在免疫调节、大脑发育与认知功能、肠道健康、骨健康等方面具有重要的营养健康作用,可作为新食品原料用于婴配粉等食品中。本文着重对乳骨桥蛋白的结构特征、消化吸收和营养功能研究进展进行阐述,对乳骨桥蛋白作为新食品原料的应用前景和研究方向进行展望,为乳骨桥蛋白的开发利用提供参考。 展开更多
关键词 乳骨桥蛋白 结构特征 消化吸收 营养功能
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我国高校绩效评价:概念、结构和功能
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作者 王贺元 胡赤弟 《江苏高教》 北大核心 2025年第7期53-61,共9页
当前高校绩效评价的认知多从单个评价着手,如政府对高校评价、高校对二级学院评价、学院对教师评价等等,彼此孤立,缺乏总体性系统性认识。基于高校发展这一根本目标,高校绩效评价有必要从整体和系统性角度来研究其概念、结构和功能。高... 当前高校绩效评价的认知多从单个评价着手,如政府对高校评价、高校对二级学院评价、学院对教师评价等等,彼此孤立,缺乏总体性系统性认识。基于高校发展这一根本目标,高校绩效评价有必要从整体和系统性角度来研究其概念、结构和功能。高校绩效评价不是一项具体的办学活动,而是建立在制度体系上的一种治理机制,价值性、过程性、学术性和多元性是其基本内涵。从结构功能理论出发,高校绩效评价可以分为要素结构、组织结构和过程结构,其相应的功能体现为:效率基础上的资源优化功能、共同价值基础上的发展激励功能、达标评判基础上的制度创新功能。 展开更多
关键词 高校 绩效评价 概念 结构 功能
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