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A trajectory shaping guidance law with field-of-view angle constraint and terminal limits

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Journal of Systems Engineering and Electronics 2022年第2期33卷 426-437页

作者： FU Shengnan zhou Guanqun xia Qunli School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Aerospace Technology Institute Beijing 100074China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

In this paper, a trajectory shaping guidance law,which considers constraints of field-of-view(FOV) angle, impact angle, and terminal lateral acceleration, is proposed for a constant speed missile against a stationary target. First, to decouple constraints of the FOV angle and the terminal lateral acceleration, the third-order polynomial with respect to the line-ofsight(LOS) angle is introduced. Based on an analysis of the relationship between the looking angle and the guidance coefficient,the boundary of the coefficient that satisfies the FOV constraint is obtained. The terminal guidance law coefficient is used to guarantee the convergence of the terminal conditions. Furthermore, the proposed law can be implemented under bearingsonly information, as the guidance command does not involve the relative range and the LOS angle rate. Finally, numerical simulations are performed based on a kinematic vehicle model to verify the effectiveness of the guidance law. Overall, the work offers an easily implementable guidance law with closed-form guidance gains, which is suitable for engineering applications.

关键词： shaping guidance law field-of-view(FOV)constraint impact angle constraint terminal lateral acceleration constraint

An epididymis-specific carboxyl esterase CES5A is required for sperm capacitation and male fertility in the rat

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Asian Journal of Andrology 2015年第2期17卷 292-297,I0010,I0011页

作者： Yan-Fei ru Hai-Min Xue Zi-Mei Ni Dong xia Yu-Chuan zhou Yong-Lian Zhang Shanghai Key Laboratory of Molecular Andrology State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Shanghai China University of Chinese Academy of Sciences Beijing China Institute of Animal Husbandry and Veterinary Sciences Shanghai Academy of Agricultural Sciences Shanghai China Shanghai Institute of Planned Parenthood Research Shanghai China.

Despite the fact that the phenomenon of capacitation was discovered over half century ago and much progress has been made in identifying sperm events involved in capacitation, few specific molecules of epididymal origin have been identified as being directly involved in this process in vivo. Previously, our group cloned and characterized a carboxyl esterase gene CesSa in the rat epididymis. The CES5A protein is mainly expressed in the corpus and cauda epididymidis and secreted into the corresponding lumens. Here, we report the function of CESSA in sperm maturation. By local injection of Lentivirus-mediated siRNA in the *** region of the rat epididymis, CesSa-knockdown animal models were created. These animals exhibited an inhibited sperm capacitation and a reduction in male fertility. These results suggest that CESSA plays an important role in sperm maturation and male fertility.

关键词： carboxylesterase CES5A epididymis male fertility sperm capacitation

One-pot synthesis of Fe/Cu-SSZ-13 catalyst and its highly efficient performance for the selective catalytic reduction of nitrogen oxide with ammonia

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Journal of Environmental Sciences 2021年第2期33卷 306-316页

作者： Jie Wan Jiawei Chen ru Zhao Renxian zhou Energy Research Institute Nanjing Institute of TechnologyNanjing 211167China Institute of Catalysis Zhejiang UniversityHangzhou 310028China

Series of Fe/Cu-SSZ-13 catalysts with different Fe loading content were synthesized by simple one-pot *** obtained catalysts were subjected to selective catalytic reduction(SCR)of NO x with NH 3 and were characterized by various *** results show that Fe 0.63/Cu 1.50-SSZ-13 catalyst with proper Fe content exhibits excellent catalytic activity with widest operation temperature window from 160 to 580℃,excellent hydrothermal stability as well as good resistance to sulfur poisoning when compared with Cu-SSZ-13,signifying its great potential for practical *** characterizations reveal that the synthesized Fe/Cu-SSZ-13 catalysts present typical chabazite(CHA)structure with good crystallinity,while isolated Cu^2+and monomeric Fe 3+are revealed as the predominant copper and iron *** low temperatures,isolated Cu^2+species act as primary active sites for SCR reaction,while monomeric Fe^3+species provide sufficient active sites for sustain the SCR activity at high ***,Fe over doping would lead to the damage of zeolite structure,destruction of isolated Cu^2+site,as well as the formation of highly oxidizing Fe2O3,thus causing deterioration of catalytic performances.

关键词： NH3-SCR Fe/Cu-SSZ-13 One-pot synthesis Active species

不同强度运动抑制糖尿病大鼠肾脏PI3K/AKT/mTOR信号通路改善自噬的比较

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中国组织工程研究 2025年第11期29卷 2310-2318页

作者：周鸿雁张译丹季威刘霞湖南文理学院体育学院湖南省常德市415000 湖南师范大学体育学院体适能与运动康复湖南省重点实验室湖南省长沙市410012

背景:2型糖尿病损害肾功能。研究表明运动干预可以保护肾脏;鸢尾素可以通过抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路恢复自噬,保护糖尿病肾病患者的肾功能。目的:探讨运动能否通过抑制肾脏磷脂酰肌醇3-激酶/蛋白激酶B/... 详细信息

背景:2型糖尿病损害肾功能。研究表明运动干预可以保护肾脏;鸢尾素可以通过抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路恢复自噬,保护糖尿病肾病患者的肾功能。目的:探讨运动能否通过抑制肾脏磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路过度激活来恢复自噬,改善肾损伤,以及分析不同方式运动产生影响的差异。方法:将6周龄的SD大鼠随机分为空白对照组(正常大鼠)和糖尿病组,其中糖尿病组大鼠经过高脂高糖喂养加腹腔注射低剂量1%链脲佐菌素(30 mg/kg)建立2型糖尿病模型。造模成功后再将糖尿病组大鼠随机分成糖尿病模型组、中强度持续运动组和高强度间歇运动组。两个运动组大鼠分别进行8周不同强度运动干预。取材后采用葡萄糖氧化酶法检测大鼠空腹血糖,使用试剂盒检测糖化血红蛋白水平,Elisa法检测血清胰岛素浓度,计算胰岛素抵抗指数,RT-PCR检测肾组织磷脂酰肌醇3-激酶、蛋白激酶B、雷帕霉素靶蛋白、Beclin-1、podocin、nephrin的基因表达量,Western Blot检测肾组织雷帕霉素靶蛋白及自噬标记蛋白LC3-1、LC3-2、Beclin-1的蛋白表达量。结果与结论:①2型糖尿病大鼠空腹血糖和糖化血红蛋白水平极显著性升高,胰岛素抵抗水平显著上升,胰岛素水平显著下降;两种运动均能使2型糖尿病大鼠空腹血糖和糖化血红蛋白水平极显著下降,胰岛素抵抗水平显著下降,胰岛素水平显著上升;与中强度持续运动组相比,高强度间歇运动组胰岛素水平显著上升。②2型糖尿病大鼠podocin、nephrin基因表达量显著降低;两种不同形式运动均能显著提高其表达;与高强度间歇运动组相比,中等强度持续性运动组足细胞相关蛋白基因表达有进一步上升趋势,但无显著性差异。③2型糖尿病大鼠肾组织磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及蛋白的表达量显著增加,自噬标志蛋白Beclin-1、LC3-2表达量以及LC3-2/LC3-1显著降低;两种不同形式运动均能使肾组织磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及雷帕霉素靶蛋白蛋白的表达量显著降低,自噬标志蛋白Beclin-1、LC3-2以及LC3-2/LC3-1显著升高;与中等强度持续性运动组相比,高强度间歇运动的磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及雷帕霉素靶蛋白的蛋白表达量有进一步下降的趋势,Beclin-1、LC3-2以及LC3-2/LC3-1有进一步升高的趋势,但仅Beclin-1有显著性差异。④结果说明2型糖尿病肾脏足细胞损伤,自噬受到抑制,与磷脂酰肌醇3-激酶/蛋白激酶B/mTORC1信号通路被异常激活密切相关。高强度间歇运动和中等强度持续性运动可以保护糖尿病肾脏,减少足细胞损伤,促进自噬恢复,这可能与运动抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路过度激活有关。与中等强度持续性运动相比,高强度间歇运动恢复自噬的效果呈更优趋势,但足细胞蛋白表达稍有下降。

关键词：糖尿病肾病足细胞自噬高强度间歇运动中等强度持续性运动 PI3K AKT mTOR

Numerical analysis of magnetization AC losses in high-temperature superconducting slabs subjected to uniform strains

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Science China(Technological Sciences) 2014年第4期57卷 765-772页

作者： xia Jing zhou YouHe Key Laboratory of Mechanics on Disaster and Environment in Western China attached to the Ministry of Education of China and Department of Mechanics and Engineering Sciences College of Civil Engineering and Mechanics Lanzhou University

High-temperature superconductors in superconductor apparatuses are subjected to mechanical strains under operating *** strains cause the degradation of the critical current densities and influence AC losses in the *** on the dynamic process of thermomagnetic interaction,we report the results of numerical analysis of AC losses in an infinite high-temperature superconducting slab subjected to a uniform in-plane strain in an alternating external magnetic field parallel to the sample *** numerical analysis shows the details of electromagnetic phenomena in the slab and the dependences of AC loss on various external parameters including the uniform strain in the slab and the amplitude and frequency of the external magnetic *** this paper,we find that whether the magnetic field fully penetrates the superconductor is the key factor that influences the features of AC *** the magnetic field cannot fully penetrate the superconductor,the loss rises with increasing strain or decreasing *** the magnetic field can fully penetrate the superconductor,the feature is just *** also analyze the effects of periodic strain on AC *** is interesting to find that when the periodic strain frequency equals the external magnetic field frequency,the AC loss reaches the maximum,regardless if the magnetic field fully penetrates the superconductor or not.

关键词： high-temperature superconducting slab AC loss strain

Estimated conditional score function for missing mechanism model with nonignorable nonresponse

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Science China Mathematics 2017年第7期60卷 1197-1218页

作者： CUI xia zhou Yong School of Economics and Statistics Guangzhou University Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Statistics and Management Shanghai University of Finance and Economics

Missing data mechanism often depends on the values of the responses,which leads to nonignorable *** such a situation,inference based on approaches that ignore the missing data mechanism could not be valid.A crucial step is to model the nature of *** specify a parametric model for missingness mechanism,and then propose a conditional score function approach for *** approach imputes the score function by taking the conditional expectation of the score function for the missing data given the available *** procedure is then followed by replacing unknown terms with the related nonparametric estimators based on the observed *** proposed score function does not suffer from the non-identifiability problem,and the proposed estimator is shown to be consistent and asymptotically *** also construct a confidence region for the parameter of interest using empirical likelihood *** studies demonstrate that the proposed inference procedure performs well in many *** apply the proposed method to a data set from research in a growth hormone and exercise intervention study.

关键词： conditional score function empirical likelihood missing data nonignorabe nonresponse

PHASE TRANSITION IN SEQUENCE UNIQUE RECONSTruCTION

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Journal of Systems Science & Complexity 2007年第1期20卷 18-29页

作者： Li xia Chan zhou Theoretical Life Science Research Center Fudan University Shanghai 200433 China James D. Waston Institute of Genome Sciences Zhejiang University Hangzhou 310008 China.

In this paper, sequence unique reconstruction refers to the property that a sequence is uniquely reconstructable from all its K-tuples. We propose and study the phase transition behavior of the probability P（K） of unique reconstruction with regard to tuple size K in random sequences （iid model）. Based on Monte Carlo experiments, artificial proteins generated from lid model exhibit a phase transition when P（K） abruptly jumps from a low value phase （e.g. 〈 0.1） to a high value phase （e.g. 〉 0.9）. With a generalization to any alphabet, we prove that for a random sequence of length L, as L is large enough, P（K） undergoes a sharp phase transition when p ≤ 0.1015 where p = P （two random letters match）. Besides, formulas are derived to estimate the transition points, which may be of practical use in sequencing DNA by hybridization. Concluded from our study, most proteins do not deviate greatly from random sequences in the sense of sequence unique reconstruction, while there are some ＂stubborn＂ proteins which only become uniquely reconstructable at a very large K and probably have biological implications.

关键词： Phase transition probability protein sequence SBH unique reconstruction

Studies on the esterifications of 9-(hydroxyimino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one with acid chlorides under different conditions

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Chinese Chemical Letters 2008年第7期19卷 791-794页

作者： ru Shu Sun Yang Wang Peng xia Department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 China

The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as the acid scavenger, whereas the reactions gave unexpected 8-substituted products N-（8-chloro-4-methyl-2-oxo-2H-furo-[2,3-h]chromen-9-yl）amides （5a-c） and 4-methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloates （6d-e） by using excessive acid chlorides. The structures of 10 new compounds were determined by 1H NMR, 13C NMR, MS and HRMS, and the possible mechanism for the formation of unexpected products 5a--c and 6d-e was also proposed.

关键词： 9-(Hydroxyirnino)-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one Oxime-ester N-(8-Chloro-4-methyl-2-oxo-2H-furo[2,3-h]chro-men-9-yl)amide 4-Methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloate

Chlorocholine chloride and paclobutrazol treatments promote carbohydrate accumulation in bulbs of Lilium Oriental hybrids 'Sorbonne'

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第2期13卷 136-144页

作者： Ri-ru ZHENG Yun WU Yi-ping xia Department of Horticulture College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310029China College of Horticulture and Forestry Sciences Huazhong Agricultural UniversityWuhan 430070China

The present study was to test the hypothesis that the plant growth retardants chlorocholine chloride(CCC) and paclobutrazol(PBZ)could improve the carbohydrate accumulation in lily bulbs by enhancing photosynthetic capacity and changing endogenous *** of Lilium Oriental hybrids'Sorbonne'were treated with a foliar spray of CCC or PBZ(both at 300 mg/L)solution,at six weeks after planting(6 WAP).The morphological parameters,endogenous hormone contents(gibberellic acid(GA),abscisic acid(ABA),and indole-3-acetic acid(IAA)),and carbohydrate contents were measured from 6 to 18 WAP,at 2-week *** results showed that CCC increased the biomass of leaves and stems which might produce more photoassimilates available for transportation and ***,PBZ treatment suppressed vegetative growth and favored photoassimilate transportation into bulbs.A slight delay of bud and anthesis formation was observed in both treated *** and PBZ treatments substantially enhanced the sucrose contents in leaves probably due to the increase of chlorophyll *** with CCC or PBZ decreased GA but increased IAA contents in lily bulbs which might stimulate starch accumulation and formation of new *** experiment suggested that CCC or PBZ treatment is an effective method to promote carbohydrate accumulation in lily bulbs.

关键词： Carbohydrate Chlorocholine chloride Gibberellic acid Lilium Oriental hybrids 'Sorbonne' Paclobutrazol