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Evidence for the paternal mitochondrial DNA in the crucian carp-like fish lineage with hybrid origin

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Science China(Life Sciences) 2020年第1期63卷 102-115页

作者： Shi Wang Ni Jiao lu Zhao Meiwen zhang pei Zhou Xuexue Huang Fangzhou Hu Conghui Yang Yuqin Shu Wuhui Li Chun zhang Min Tao Bo Chen Ming Ma Shaojun Liu State Key Laboratory of Developmental Biology of Freshwater Fish Hunan Normal UniversityChangsha 410081China College of Life Sciences Hunan Normal UniversityChangsha 410081China College of Chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410081China Key Laboratory of Tropical and Subtropical Fisheries Resource Application and Cultivation Ministry of AgriculturePearl River Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhou 510380China

In terms of taxonomic status,common carp(Cyprinus carpio,Cyprininae)and crucian carp(Carassius auratus,Cyprininae)are different species;however,in this study,a newborn homodiploid crucian carp-like fish(2n=100)(2nNCRC)lineage(F1–F3)was established from the interspecific hybridization of female common carp(2n=100)×male blunt snout bream(Megalobrama amblycephala,Cultrinae,2n=48).The phenotypes and genotypes of 2 n NCRC differed from those of its parents but were closely related to those of the existing diploid crucian *** further sequenced the whole mitochondrial(mt)genomes of the 2n NCRC lineage from F1 to *** paternal mt DNA fragments were stably embedded in the mt-genomes of F1–F3 generations of 2n NCRC to form chimeric DNA *** with this chimeric process,numerous base sites of F1–F3 generations of 2 n NCRC underwent *** of these mutation sites were consistent with the existing diploid crucian ***,the mt DNA organization and nucleotide composition of 2n NCRC were more similar to those of the existing diploid crucian carp than those of the *** inheritable chimeric DNA fragments and mutant loci in the mt-genomes of different generations of 2nNCRC provided important evidence of the mt DNA change process in the newborn lineage derived from hybridization of different *** findings demonstrated for the first time that the paternal mt DNA were transmitted into the mt-genomes of homodiploid lineage,which provided new insights into the existence of paternal mt DNA in the mt DNA inheritance.

关键词： hybridization homodiploid common carp blunt snout bream crucian carp mitochondrial genome genetic evolution

METTL3表达水平对口蹄疫病毒复制的影响

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中国兽医科学 2024年第8期54卷 1010-1018页

作者：张继燕李伟伟范许许曹雪静朱兆宇裴丹诗王一卓何路李熙忠任青峰张伟王川郑海学甘肃农业大学动物医学院甘肃兰州州730070 中国农业科学院兰州兽医研究所兰州大学动物医学与生物安全学院动物疫病防控全国重点实验室国家口蹄疫参考实验室甘肃兰州730000 河南农业大学动物医学院河南郑州450046 甘肃农业大学生命科学技术学院甘肃兰州730070

利用CRISPR/Cas9系统构建了METTL3基因敲除细胞系(BHK-21),随后用口蹄疫病毒(FMDV)分别感染野生型和METTL3敲除BHK-21细胞,通过q PCR、Western-blot和TCID50方法检测FMDV在上述2株细胞中的复制情况。结果表明,敲除METTL3显著抑制FMDV的... 详细信息

利用CRISPR/Cas9系统构建了METTL3基因敲除细胞系(BHK-21),随后用口蹄疫病毒(FMDV)分别感染野生型和METTL3敲除BHK-21细胞,通过q PCR、Western-blot和TCID50方法检测FMDV在上述2株细胞中的复制情况。结果表明,敲除METTL3显著抑制FMDV的复制。为了进一步验证METTL3的表型功能,利用慢病毒包装系统构建METTL3稳定表达细胞系。用FMDV分别感染野生型和METTL3过表达BHK-21细胞,通过q PCR和TCID50试验测定FMDV在这2株细胞中的复制情况。结果显示,过量表达METTL3促进FMDV的复制。此外,激光共聚焦显微镜试验显示,FMDV感染BHK-21细胞后,METTL3从细胞核迁移至细胞质,其细胞定位的改变表明METTL3可能参与调控FMDV基因组的转录过程。本研究中成功构建了METTL3基因敲除和过表达的BHK-21细胞系,首次发现该分子正向调控FMDV的复制。上述实验结果为进一步开展METTL3在宿主细胞中调控FMDV复制的机制研究奠定了可靠的数据基础。

关键词： METTL3 m6A修饰口蹄疫病毒

Unbiased Quasi-regression

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Chinese Annals of Mathematics,Series B 2007年第2期28卷 177-186页

作者： Guijun YANG lu LIN Runchu zhang Department of Statistics Tianjin University of Finance and Economics Tianjin 300222 China School of Mathematics and System Sciences Shandong University Jinan 250100 China. LPMC and School of Mathematical Sciences Nankai University Tianjin 300071 China.

Quasi-regression, motivated by the problems arising in the computer experiments, focuses mainly on speeding up evaluation. However, its theoretical properties are unexplored systemically. This paper shows that quasi-regression is unbiased, strong convergent and asymptotic normal for parameter estimations but it is biased for the fitting of curve. Furthermore, a new method called unbiased quasi-regression is proposed. In addition to retaining the above asymptotic behaviors of parameter estimations, unbiased quasi-regression is unbiased for the fitting of curve.

关键词： Computer experiment Quasi-regression Unbiasedness Fitting of curve Asymptotic normality

XOD模式价值实现机制及隐性债务风险防范探讨——以水安全保障导向的开发(WOD)模式为例

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水利发展研究 2024年第1期24卷 20-26页

作者：张建红翟广永裴晓桃中国国际工程咨询有限公司北京100048 北京市南水北调环线管理处北京100176 北京经济管理职业学院北京100102

当前,单一靠财政投入已远不能满足城乡建设发展的需要,XOD模式作为一种创新型的项目组合实施方式应运而生。XOD的核心机理是“增肥哺瘦”,需要通过组合投资、溢价回收、协同增效3大机制和关联关系、一体开发、自求平衡3大原则来实现。实... 详细信息

当前,单一靠财政投入已远不能满足城乡建设发展的需要,XOD模式作为一种创新型的项目组合实施方式应运而生。XOD的核心机理是“增肥哺瘦”,需要通过组合投资、溢价回收、协同增效3大机制和关联关系、一体开发、自求平衡3大原则来实现。实施WOD项目通常需要经过5大阶段。通过分析运行机制和操作流程,发现WOD模式在实施过程中,如操作不当,也会存在地方政府隐性债务风险。通过优化WOD运行条件、依法合规实施项目、构建全过程风险管控体系等措施,可以从一定程度上降低WOD项目的隐性债务风险。

关键词： XOD模式 WOD模式价值实现机制地方政府隐性债务风险操作流程

Optimizing the Gabor Bandwidth of satellite navigation signals by MCS signal expression

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Science China(Physics,Mechanics & Astronomy) 2011年第6期54卷 1077-1082页

作者： zhang XiaoMing YAO Zheng lu MingQuan Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing Global Information Center Beijing 100094China

Satellite navigation is playing an important role in social *** performances of the services a navigation system provides are the concern of the builders and *** signal structure determines the inherent ability of a satellite navigation system to provide these ***,it is necessary and reasonable to optimize the signal in the initial *** waveforms of signals in satellite navigation chips are an important aspect of the signal's structure,which impact the characteristics of the autocorrelation function and power spectrum in the time domain and frequency *** range accuracy of a navigation system is usually described by its Gabor *** Gabor Bandwidth of the Binary Offset Carrier (BOC) modulation in next-generation GNSS signal systems is not *** paper presents a signal expression based on Multilevel Coded Symbol (MCS) signals,which can describe the fine structure of navigation *** this expression,we can optimize the Gabor Bandwidth of the signal,and find out the corresponding MCS vector and chip waveform,so as to get higher range *** method in this paper,in theory,is of great value in the design of next-generation navigation signals.

关键词： satellite navigation MCS signal Gabor Bandwidth bound

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疼痛抑郁共病的研究进展

湖北科技学院学报（医学版） 2024年第3期38卷 270-276页

作者：张培根朱海丽高卉湖北科技学院医学部药学院湖北咸宁437100 湖北科技学院医学部基础医学院湖北科技学院医学部临床医学院

疼痛抑郁共病是一种常见且复杂的疾病状态,严重危害患者的身心健康。本文就目前国内外疼痛抑郁共病的研究,简述了相关动物的模型建立、行为学评价、发病机制和治疗方法,揭示了疼痛和抑郁症之间存在潜在的神经生物学关系,指出其治疗手段... 详细信息

疼痛抑郁共病是一种常见且复杂的疾病状态,严重危害患者的身心健康。本文就目前国内外疼痛抑郁共病的研究,简述了相关动物的模型建立、行为学评价、发病机制和治疗方法,揭示了疼痛和抑郁症之间存在潜在的神经生物学关系,指出其治疗手段主要为药物治疗、心理治疗以及物理疗法。未来的研究方向可以包括深入探索疼痛和抑郁症之间的病理生理机制、发展更符合患者需求的诊断和治疗策略以及探索新的治疗方法等。

关键词：疼痛抑郁共病动物模型神经机制治疗方法

维普期刊数据库博看期刊

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基于蒙特卡洛模拟的转子压缩机性能预测研究

制冷与空调 2024年第1期24卷 102-108页

作者：房元灿金培张琼宇谷轮环境科技(苏州)有限公司

在转子压缩机关键零件的加工尺寸精度和压缩机性能的关联基础上,建立物理数学模型,采用蒙特卡洛仿真模拟,生成满足指定尺寸公差条件的一系列随机值,并获得压缩机的性能输出,通过对输出数据的统计和分析,可以认为抽样数量越多,模拟结果... 详细信息

在转子压缩机关键零件的加工尺寸精度和压缩机性能的关联基础上,建立物理数学模型,采用蒙特卡洛仿真模拟,生成满足指定尺寸公差条件的一系列随机值,并获得压缩机的性能输出,通过对输出数据的统计和分析,可以认为抽样数量越多,模拟结果的输出越稳定。同时,对不同零件的加工尺寸精度的调整所获得的模拟输出,可以作为设计敏感度的分析依据,用于设计制造优化的参考。

关键词：转子压缩机蒙特卡洛尺寸公差性能

用于催化裂化装置强制循环泵的三元导叶设计方法及性能分析研究

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风机技术 2024年第2期66卷 31-37页

作者：裴林李国君张建茹西安交通大学热流科学与工程教育部重点实验室沈鼓集团股份有限公司

强制循环泵是催化裂化装置烟气热量回收系统中重要的水循环动力设备,蜗壳为半球形结构带导叶的luV型泵是一种广泛应用的强制循环泵,其导叶结构对泵的性能有着至关重要的影响。本文针对强制循环泵二元导叶在不同叶高处的进口叶片安装角... 详细信息

强制循环泵是催化裂化装置烟气热量回收系统中重要的水循环动力设备,蜗壳为半球形结构带导叶的luV型泵是一种广泛应用的强制循环泵,其导叶结构对泵的性能有着至关重要的影响。本文针对强制循环泵二元导叶在不同叶高处的进口叶片安装角与水流角不匹配的问题,发展了采用后盖板和前盖板的叶片中弧线角度分布和叶片厚度分布来构建叶型的三元导叶叶片结构设计方法,并数值研究了导叶后盖板和前盖板处进出口叶片安装角对泵额定工况效率和内部流动特性的影响。结果表明:随着前后盖板叶片进出口安装角中一个变量的增大,额定流量点效率均先增大后减小;设计的三元导叶方案比二元导叶方案在额定工况下的效率提高了0.9%;后盖板附近的叶片安装角与水流角的匹配性对泵的效率起到了更加重要的作用;三元导叶方案在后盖板附近0.1叶高截面上进口水流角与叶片安装角的匹配关系得到改善,此截面上的旋涡区减少,导叶内的能量耗散减小。

关键词：强制循环泵离心泵数值模拟导叶设计导叶进出口角流动分析

Global gaps in age data based on skeletochronology for amphibians

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Integrative Zoology 2022年第5期17卷 752-763页

作者： Zhiwei PENG Lixia zhang Xin lu Department of Ecology College of Life SciencesWuhan UniversityWuhanChina Department of Ecology College of Life SciencesHenan Normal UniversityXinxiangChina

Individual age and population age composition are the major concerns of ecologists,evolutionary biologists and conservation *** amphibians,skeletochronology-counting the number of lines of arrested growth deposited in the bone tissue,is the dominant method to determine actual age of an *** 1970s,age data of the ectothermic taxa have been accumulated and increasingly used in comparative *** we make a global assessment for the availability of the data,based on a collection of 369 published *** a specific species,more males than females were *** the extant 8146 amphibian species,only 266(3.3%)have been skeletochronologically *** these studied species,2(0.9%of 214)belong to caecilians,56(7.6%of 740)salamanders and 208(2.9%of 7192)anurans.A complete paucity of data was seen in 80%,50%,and 54%of families in the corresponding *** temperate species than tropical species were sampled,while the proportion of Palearctic species studied was higher than that in the other 5 biogeographical *** inhabiting semi-aquatic niche were more likely to be studied than fossorial or plant *** information of multiple populations(2-48)was available for species with a broad distribution,accounts for 61%of salamander and 43%of anuran species *** these gaps in demographic knowledge can limit our understanding of questions ranging from life history evolution,population dynamics to conservation,we encourage herpetologists to pay more efforts on filling them.

关键词： amphibia demography life-history trait review