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粗饲料对反刍动物瘤胃微生物和生产性能的影响研究进展

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饲料研究 2024年第5期47卷 133-138页

作者：杜海东李科南娜梅拉娜仁花内蒙古农业大学动物科学学院内蒙古呼和浩特010018

粗饲料在维持反刍动物健康和提高生产性能方面起着重要作用。粗饲料经瘤胃内的微生物发酵降解为可吸收利用的物质,可以维持机体的正常生命活动。粗饲料通过刺激动物反刍、唾液分泌和瘤胃发育可以维持瘤胃健康。粗饲料摄入量不足会导致... 详细信息

粗饲料在维持反刍动物健康和提高生产性能方面起着重要作用。粗饲料经瘤胃内的微生物发酵降解为可吸收利用的物质,可以维持机体的正常生命活动。粗饲料通过刺激动物反刍、唾液分泌和瘤胃发育可以维持瘤胃健康。粗饲料摄入量不足会导致反刍动物胃肠道损伤、营养缺乏、生产性能下降以及行为异常等问题。不同粗饲料的组织结构和营养组分差异会影响反刍动物的营养消化、能氮利用及机体代谢等。因此,饲粮中不同粗饲料来源是影响瘤胃功能和生产性能的关键因素。文章综述了不同来源粗饲料的品质及其对反刍动物瘤胃微生物、机体代谢和生产性能的影响,并对其作用机制进行阐述,为粗饲料在反刍动物中的合理利用提供参考。

关键词：粗饲料反刍动物代谢生产性能瘤胃微生物

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Theoretical Analysis of Structural Characteristics of Morin Rearrangement for Cephalosporins Prepared from Penicillin Sulfoxide

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Chinese Journal of Structural Chemistry 2020年第9期39卷 1594-1600,1554页

作者： CHEN Guo-Hua JIANG Ning XIANG hai-Yan du hai-Bo College of Chemical Engineering Sichuan University of Science&EngineeringZigong 643000China

The structure of penicillin sulfoxide is rearranged to cephalosporins by the Morin rearrangement. It is a unit reaction for the preparation of various types of cephalosporins. In order to make better use of the reaction and in view of the shortage of the reaction theory, this study used m062x/6-311++G(d, p) to explore the possible ring-opening reaction of the penicillin sulfoxide. It is found that the isomer of(S)-sulfoxide is a necessary structure. At the same time, the intramolecular hydrogen bonding effect between the side-chain amide proton(-CONH-) and the sulfinyl oxygen(-SO) is the decisive structure factor for the formation of alkenyl in ring-opening reaction, and the best reaction path is S0-> TS2-> IN1 channel. The main effect of acid catalysis is to catalyze the dehydration reaction of sulfenic acid to form sulfur cations for subsequently ring closing reaction.

关键词： penicillin G sulfoxide morin rearrangement reaction mechanism theoretical study cephalosporins

利拉鲁肽对2型糖尿病肾病大鼠细胞焦亡、炎症细胞浸润及对NF-κB通路的影响

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河北医科大学学报 2024年第2期45卷 208-214页

作者：陈亚晖杜海波冯向峰江苏省淮安市第五人民医院肾内科江苏淮安223300

目的探究利拉鲁肽(liraglutide,LIR)对2型糖尿病肾病(diabetic nephropathy,DN)大鼠细胞焦亡、炎症细胞浸润及对核因子κB(nuclear factor-κB,NF-κB)通路的影响。方法选取45只大鼠,随机选取10只为对照组,其余35只大鼠建立DN模型,30只... 详细信息

目的探究利拉鲁肽(liraglutide,LIR)对2型糖尿病肾病(diabetic nephropathy,DN)大鼠细胞焦亡、炎症细胞浸润及对核因子κB(nuclear factor-κB,NF-κB)通路的影响。方法选取45只大鼠,随机选取10只为对照组,其余35只大鼠建立DN模型,30只大鼠建模成功,并随机分为3组(DN组及LIR高、LIR低剂量组),各10只。LIR低、高剂量组分别给予LIR 100、200 g·kg^(-1)·d^(-1),对照组及DN组给予等量的生理盐水。连续灌胃给药2周后,测量大鼠肾功能指标血清炎症因子水平,炎症细胞计数评估炎症细胞浸润情况,TUNEL染色法检测DNA损伤情况;检测细胞焦亡相关蛋白天冬氨酸特异性半胱氨酸蛋白酶1(Caspase-1)、白细胞介素1β(interleukin-1β,IL-1β)、白细胞介素18(interleukin-18,IL-18)及NF-κB通路相关蛋白的表达量。结果与对照组比较,DN组空腹血糖(fasting blood glucose,FBG)、24 h尿蛋白(urine total protein,UTP)及血尿素氮(blood urea nitrogen,BUN)、肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)、白细胞介素1β(interleukin-1β,IL-1β)、及白细胞介素6(interleukin-6,IL-6)水平升高,炎症细胞计数增多,TUNEL阳性细胞率升高,Caspase-1、IL-1β、IL-18、Toll样受体4(Toll like receptor 4,TLR4)、p-NF-κB/NF-κB及核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)蛋白表达上调(P<0.05);与DN组比较,LIR低、高剂量组FBG、UTP及BUN水平降低,TNF-α、IL-1β及IL-6水平降低,炎症细胞计数减少,TUNEL阳性细胞率降低,Caspase-1、IL-1β、IL-18、TLR4、p-NF-κB/NF-κB及NLRP3蛋白表达下调(P<0.05);与LIR低剂量组比较,LIR高剂量组FBG、UTP及BUN水平降低,TNF-α、IL-1β及IL-6水平降低,炎症细胞计数减少,TUNEL阳性细胞率降低,Caspase-1、IL-1β、IL-18、TLR4、p-NF-κB/NF-κB及NLRP3蛋白表达下调(P<0.05)。结论LIR能够改善2型DN大鼠炎症细胞浸润,抑制细胞焦亡,其作用机制可能抑制NF-κB通路有关。

关键词：糖尿病肾病利拉鲁肽 NF-κB

Application of SVM in Analyzing the Headstream of Gushing Water in Coal Mine

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Journal of China University of Mining and Technology 2006年第4期16卷 433-438页

作者： YAN Zhi-gang ZHANG hai-rong du Pei-jun School of Environment and Spatial Informatics China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

To recognize the presence of the headstream of gushing water in coal mines, the SVM (Support Vector Ma- chine) was proposed to analyze the gushing water based on hydrogeochemical methods. First, the SVM model for head- stream analysis was trained on the water sample of available headstreams, and then we used this to predict the unknown samples, which were validated in practice by comparing the predicted results with the actual results. The experimental results show that the SVM is a feasible method to differentiate between two headstreams and the H-SVMs (Hierachical SVMs) is a preferable way to deal with the problem of multi-headstreams. Compared with other methods, the SVM is based on a strict mathematical theory with a simple structure and good generalization properties. As well, the support vector W in the decision function can describe the weights of the recognition factors of water samples, which is very important for the analysis of headstreams of gushing water in coal mines.

关键词： support vector machine gushing water headstream recogmtlon H-SVMs

Robust Face Recognition via Low-rank Sparse Representation-based Classification

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International Journal of Automation and computing 2015年第6期12卷 579-587页

作者： hai-Shun du Qing-Pu Hu Dian-Feng Qiao Ioannis Pitas Institute of Image Processing and Pattern Recognition Henan University Department of Informatics Aristotle University of Thessaloniki

Face recognition has attracted great interest due to its importance in many real-world applications. In this paper,we present a novel low-rank sparse representation-based classification(LRSRC) method for robust face recognition. Given a set of test samples, LRSRC seeks the lowest-rank and sparsest representation matrix over all training samples. Since low-rank model can reveal the subspace structures of data while sparsity helps to recognize the data class, the obtained test sample representations are both representative and discriminative. Using the representation vector of a test sample, LRSRC classifies the test sample into the class which generates minimal reconstruction error. Experimental results on several face image databases show the effectiveness and robustness of LRSRC in face image recognition.

关键词： Face recognition image classification sparse repre

Clonal Strategy Algorithm Based on the Immune Memory

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Journal of Computer Science & Technology 2005年第5期20卷 728-734页

作者： Ruo-Chen Liu Li-Cheng Jiao hai-Feng du Institute of Intelligent Information Processing Xidian University Xi＇an 710071 P.R. China Department of Mathematics Northwest University Xi＇an 710069 P.R. China

Based on the clonal selection theory and immune memory mechanism in the natural immune system, a novel artificial immune system algorithm, Clonal Strategy Algorithm based on the Immune Memory （CSAIM）, is proposed in this paper. The algorithm realizes the evolution of antibody population and the evolution of memory unit at the same time, and by using clonal selection operator, the global optimal computation can be combined with the local searching. According to antibody-antibody （Ab-Ab） affinity and antibody-antigen （Ab-Ag） affinity, the algorithm can allot adaptively the scales of memory unit and antibody population. It is proved theoretically that CSAIM is convergent with probability 1. And with the computer simulations of eight benchmark functions and one instance of traveling salesman problem （TSP）, it is shown that CSAIM has strong abilities in having high convergence speed, enhancing the diversity of the population and avoiding the premature convergence to some extent.

关键词： artificial immune system clonal selection, immune memory evolutionary computation, traveling salesman problem

Epigenetic Modifications of mRNA and DNA in Plants

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Molecular Plant 2020年第1期13卷 14-30页

作者： Zhe Liang Adeel Riaz Sadaruddin Chachar Yike Ding hai du Xiaofeng Gu biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China Centre for Organismal Studies Heidelberg UniversityHeidelberg 69120Germany Department of Entomology University of California RiversideRiversideCA 92521USA College of Agronomy and Biotechnology Southwest UniversityChongqing 400715China

Advances in the detection and mapping of messenger RNA(mRNA)N^6-methyladenosine(m 6A)and 5-methylcytosine(m 5C),and DNA N^6-methyldeoxyadenosine(6mA)redefined our understanding of these modifications as additional tiers of epigenetic *** plants,the most prevalent internal mRNA modifications,m^6A and m^5C,play crucial and dynamic roles in many processes,including embryo development,stem cell fate determination,trichome branching,leaf morphogenesis,floral transition,stress responses,fruit ripening,and root *** newly identified and widespread epigenetic marker 6mA DNA methylation is associated with gene expression,plant development,and stress ***,we review the latest research progress on mRNA and DNA epigenetic modifications,including the detection,dynamics,distribution,functions,regulatory proteins,and evolution,with a focus on m^6A,m^5C,and *** also provide some perspectives on future research of the newly identified and unknown epigenetic modifications of mRNA and DNA in plants.

关键词： RNA modification m^6A m^5C DNA methylation 6mA epigenetics

高管薪酬、社会责任与价值创造——来自中国资本市场的经验证据

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当代金融研究 2024年第4期7卷 57-72页

作者：张婷李刚蒲咏秋杜海旋泰国易三仓大学科学技术学院曼谷10250 四川水利职业技术学院管理工程学院四川成都611130 四川农业大学管理学院四川成都611130

高管薪酬制度设计是能否缓解委托代理问题的重要治理机制,高管薪酬与社会责任履行影响着企业价值创造成效。选取2016-2020年沪深两市A股上市公司作为研究对象,实证探究高管薪酬对价值创造的影响机制,并考察社会责任的中介效应。研究发现... 详细信息

高管薪酬制度设计是能否缓解委托代理问题的重要治理机制,高管薪酬与社会责任履行影响着企业价值创造成效。选取2016-2020年沪深两市A股上市公司作为研究对象,实证探究高管薪酬对价值创造的影响机制,并考察社会责任的中介效应。研究发现:高管薪酬越高,企业价值创造越高,社会责任在高管薪酬与价值创造中具有中介效应。本文将高管薪酬、社会责任与价值创造相结合,在丰富价值创造理论研究的同时,为企业设置合理高管团队薪酬、引导企业动态调整高管薪酬提供依据并提出相关建议:完善管理层激励方式,设置合理的薪酬制度,建立完善的薪酬激励约束机制;完善高管绩效考核制度,关注高管工作效率,健全企业内部监督机制;将社会责任作为高管薪酬考核的标准,完善公司治理结构,将社会责任履行纳入企业战略;积极披露履行社会责任的信息,向各方利益相关者传递积极信号,树立企业的良好形象,增加企业声誉资本。

关键词：高管薪酬社会责任价值创造

Broadband infinite-Q plasmons enable intense Smith–Purcell radiation

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Photonics Research 2023年第11期11卷 1945-1958页

作者： ZI-WEN ZHANG CHAO-hai du YU-LU LEI JUAN-FENG ZHU PU-KUN LIU Center for Carbon-based Electronics School of ElectronicsPeking UniversityBeijing 100871China State Key Laboratory of Advanced Optical Communication Systems and Networks School of ElectronicsPeking UniversityBeijing 100871China Science Mathematics and Technology(SMT)Singapore University of Technology and DesignSingapore 487372Singapore

With the rapid development of nanophotonics for enhancing free-electron radiation,bound states in the continuum(BICs)have emerged as a promising approach for emitting intense Smith–Purcell radiation(SPR)with enhanced ***,current BIC-based methods are limited to single-frequency operation,thereby restricting their applications requiring spectral and angular tunability,such as particle detectors and light *** overcome this limitation,this work proposes an approach for constructing plasmonic BICs over a broad spectral range in symmetry-broken *** leveraging the high-Q resonances near the BICs,we achieve intense SPR with broadband tunability,potentially improving the radiation intensity by six orders compared to traditional ***,we validate the construction of BIC using plasmonic antennas and achieve broadband *** proposed concept can be extended to other plasmonic or guided-wave systems,paving the way toward compact and efficient free-electron sources in hard-to-reach frequency regimes.

关键词： intense infinite enable