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Evolutionary genetics of wheat mitochondrial genomes

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The Crop Journal 2023年第6期11卷 1774-1781页

作者： hui-lin hu Fan Zhang Pei Wang Fu-Hao Lu State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 475004HenanChina Henan Key Laboratory of Big Data Analysis and Processing School of Computer and Information EngineeringHenan UniversityKaifeng 475004HenanChina School of Mathematics and Statistics Henan UniversityKaifeng 475004HenanChina

The Triticum-Aegilops complex provides ideal models for the study of polyploidization,and mitochondrial genomes(mtDNA)can be used to trace cytoplasmic inheritance and energy production following *** this study,gapless mitochondrial genomes for 19 accessions of five Triticum or Aegilops species were *** genomics confirmed that the BB-genome progenitor donated mtDNA to tetraploid ***(genome formula AABB),and that this mtDNA was then passed on to the hexaploid ***(AABBDD).T urartu(AA)was the paternal parent of ***(AAGG),and an earlier ***(DD)was the maternal parent of ***(CCDD).Genic sequences were highly conserved within species,but frequent rearrangements and nuclear or chloroplast DNA insertions occurred during *** highly variable mitochondrial genes(atp6,cob,nad6,and nad9)were established as marker genes for Triticum and Aegilops species *** BB/GG-specific atp6 and cob genes,which were imported from the nuclear genome,could facilitate identification of their diploid *** haplotypes and repeat-sequence patterns indicated that BB was much closer to GG than to ***(SS).These findings provide novel insights into the polyploid evolution of the Triticum/Aegilops complex from the perspective of mtDNA,advancing understanding of energy supply and adaptation in wheat species。

关键词： Wheat Mitochondrion mtDNA Comparative genomics Polyploidization

Stereodivergently asymmetric synthesis of chiral phosphorus compounds by synergistic combination of ion-pair catalyst and base

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Science China Chemistry 2022年第12期65卷 2500-2511页

作者： hui-lin hu Xiaoyu Ren Jiajia He Lixiang Zhu Siqiang Fang Zhishan Su Tianli Wang Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

Stereodivergently constructing the designed products having adjacent multi-stereocenters via a given reaction,with excellent control of both absolute and relative configurations,presents one of the substantial hurdles in asymmetric ***,we report a precisely stereodivergent asymmetric protocol by synergistic combination of phosphonium-involved ion-pair catalysis and base for accessing to chiral phosphorus compounds bearing two adjacent chiral centers particularly containing an acidic protonated enantioenriched carbon atom,having broad functional group compatibility in both dynamic and thermodynamic processes under mild reaction *** keys for the success in constructing these stereoisomers with high levels of regio-,diastereo-,and enantioselectivities were contained:firstly,the precise stereo-control in providing dynamic products was enabled by bifunctional phosphonium salt catalyst with semi-enclosed cavity;secondly,the readily stereospecific transformation of adducts from dynamic to thermodynamic version was initiated by achiral *** four stereoisomers could be readily accessed even in gram-scale in high yields with maintaining excellent stereoselectivities,illustrating the potential of this synergistic catalytic methodology in organic ***,mechanistic studies including density functional theory(DFT)calculations and control experiments provide insights into the mechanism.

关键词： stereodivergent asymmetric synthesis chiral phosphorus compounds dipeptided phosphonium salts cooperative catalysis base control

Implementation of the Broad-band User Access Network and the Study of the Key Algorithm for Improving the Performance of Asymmetrical Networks

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The Journal of China Universities of Posts and Telecommunications 2001年第2期8卷 77-78页

作者： LI hui lin directed by hu Zheng ming, ZHOU Ji cheng

This thesis is based on the design and development of ADSL access networks. We have completed the hardware and software functions in two main ADSL equipments: ATU C and ATU R. With the system design, we carry out researches to find out effective methods to improved performance in the following aspects: (a) how to allocate limited bandwith among services with different QoS requirements and (b) what is the effect of asymmetric links on TCP end to end flow control mechanism. We make detailed analyses and propose useful solutions to those problems we find. The main contents of this thesis are as follows: (1) the design and realization of ADSL access system. This part includes the principles of ADSL access technology, ADSL broadband access network architecture, and ATM over ADSL protocol models that we use in our system. We give detailed hardware and software design steps in this part, and list system testing results to show the system performance. In our hardware, the CPU is a RISC microprocessor. Combined with a high speed digital signal processor, the whole system can hold high reliability. Our software design platform is a pSOS multi task real time operation system. We have developed a series of hardware drivers besides other tasks for high level control and interruption processing. Currently, our system has reached the expected performance under test environment. Our next step is the development of DSLAM and in this part we give a feasible design scheme. (2) Packet scheduling policy in ADSL system. In order to optimize ATU R performance, we need a scheduling policy to regulate the order and number of packet output to the uplink. For this purpose, we study the scheduling algorithm design methods in a single network node and their performance. After studying the existing algorithms carefully, we first conclude certain important design principles and criterions for scheduling policy evaluation. And then by using service curve function, we make detailed performa

关键词： broad band access flow control ADSL technology

Unraveling brain aging through the lens of oral microbiota

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Neural Regeneration Research 2025年第7期20卷 1930-1943页

作者： Qinchao hu Si Wang Weiqi Zhang Jing Qu Guang-hui Liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Advanced Innovation Center for human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijingChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijingChina University of Chinese Academy of Sciences BeijingChina Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijingChina Aging Biomarker Consortium BeijingChina State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Beijing Institute for Stem Cell and Regenerative Medicine BeijingChina

The oral cavity is a complex physiological community encompassing a wide range of *** of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative *** studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention *** this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and *** also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

关键词： Alzheimer's disease brain aging multiple sclerosis neurodegeneration neurodegenerative diseases oral microbiota Parkinson's disease periodontitis bacteria Porphyromonas gingivalis

基于分位数回归的长白落叶松人工林最大密度线

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应用生态学报 2016年第11期27卷 3420-3426页

作者：高慧淋董利虎李凤日东北林业大学林学院哈尔滨150040

基于东北地区378块固定样地和415块临时样地的调查数据和Reineke方程,利用线性分位数回归技术建立了不同分位点(τ=0.90、0.95、0.99)下的长白落叶松人工林最大林分密度与林木平均胸径的关系模型,选出拟合长白落叶松人工林最大密度线的... 详细信息

基于东北地区378块固定样地和415块临时样地的调查数据和Reineke方程,利用线性分位数回归技术建立了不同分位点(τ=0.90、0.95、0.99)下的长白落叶松人工林最大林分密度与林木平均胸径的关系模型,选出拟合长白落叶松人工林最大密度线的最优模型.利用人为选取最大的拟合数据,采用最小二乘(OLS)和最大似然(ML)回归同时建立最大密度线模型.采用极值统计理论的广义Pareto模型推算现实林分特定径阶的极限最大株数,进一步建立极限密度线模型.将线性分位数回归模型与其他方法进行对比.结果表明:在全部径阶范围内选取5个最大数据点拟合的方法能够得到现实林分的最大密度线,选取的样点过多会使模拟结果偏离最大密度线,且ML法要优于OLS法.分位点为0.99的线性分位数回归模型能够取得与ML接近的拟合结果,但分位数回归模型参数的估计结果更稳定.人为选取拟合数据具有一定的人为性,最终选取分位点为0.99的分位数回归模型为拟合最大密度线的最优模型,参数估计结果为k=11.790、β=-1.586,极限密度线模型的参数估计结果为k=11.820、β=-1.594.所确定的极限密度线位置略高于最大密度线,但二者差异不明显.由固定样地数据的验证结果可知,所建立的最大林分密度线及极限密度线能够对现实林分的最大密度及极限密度进行预测,为长白落叶松人工林的合理经营提供依据.

关键词：长白落叶松人工林最大密度线极限密度线线性分位数回归广义Pareto模型

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混合菌固态发酵制备发酵鱼粉的研究

饲料工业 2017年第10期38卷 35-40页

作者：林俊宏朱辉林琨杰胡胜兰胡文锋华南农业大学广东广州510642 东莞市林氏生物技术股份有限公司广东东莞523560

试验旨在研究不同发酵条件对发酵鱼粉小肽含量和挥发性盐基氮的影响,确定发酵鱼粉生产工艺条件。以嗜酸乳杆菌和枯草芽孢杆菌为发酵菌株,以发酵产物小肽含量和挥发性盐基氮含量为指标,优化了混合菌固态发酵制备发酵鱼粉的生产工艺条件,... 详细信息

试验旨在研究不同发酵条件对发酵鱼粉小肽含量和挥发性盐基氮的影响,确定发酵鱼粉生产工艺条件。以嗜酸乳杆菌和枯草芽孢杆菌为发酵菌株,以发酵产物小肽含量和挥发性盐基氮含量为指标,优化了混合菌固态发酵制备发酵鱼粉的生产工艺条件,并对发酵鱼粉的总抗氧化能力和氨基酸组成进行了分析。试验结果表明,适宜的发酵鱼粉生产工艺条件为:菌种接种比(嗜酸乳杆菌枯草芽孢杆菌)12、料水比11、接种量5%、发酵温度35℃、发酵时间24 h。此条件下,发酵鱼粉小肽含量达到24.77%,挥发性盐基氮仅为42.5 mg/100 g,总抗氧化能力提升70%以上,限制性氨基酸的含量提升27.75%以上,发酵鱼粉较传统的普通鱼粉有巨大的优势,应用于饲料中具有广阔的市场前景。

关键词：鱼粉嗜酸乳杆菌枯草芽孢杆菌发酵小肽

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城市规划与扩展模型的仿真研究

计算机仿真 2011年第4期28卷 181-184,207页

作者：惠林虎屈百达徐保国江南大学江苏无锡214122

研究优化城市规划问题,由于城市规划与扩展的影响因素复杂多样,使得构建模型时需要的控制因素特征的提取十分困难。为解决城市规划精度问题,采用细胞自动系统结合G IS和遥感系统,提出了不同时期的遥感数据使用的RBF神经网络挖掘城市扩... 详细信息

研究优化城市规划问题,由于城市规划与扩展的影响因素复杂多样,使得构建模型时需要的控制因素特征的提取十分困难。为解决城市规划精度问题,采用细胞自动系统结合G IS和遥感系统,提出了不同时期的遥感数据使用的RBF神经网络挖掘城市扩展的内在规律作为细胞自动系统的转换规则,并利用规则反演和预测城市扩展信息,用1984、1991、1998和2001的遥感地图仿真了无锡2008的城市扩展,分析了影响城市扩展的因素,取得了较好的效果,仿真结果表明了RBF神经网络能够提取城市扩展内在规律并通过与细胞自动机的结合能一定程度上预测未来城市的扩展信息,提高规划精度,可为规划提供科学依据。

关键词：细胞自动系统地理信息系统城市扩展径向基函数神经网络

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高速梯的限速器研究与改进

电子设计工程 2015年第17期23卷 87-90页

作者：惠林虎王义贵州师范大学物理与电子科学学院贵州贵阳550025

文中针对传统机械限速器动作速度不能跟随轿厢速度、动作速度不精确等问题,提出了机械-电子限速器,在不改变原有机械限速器的基础上增加了电子限速器来改善其性能。文中给出了机械-电子限速器的结构、控制及原理,在此基础上设计了电子... 详细信息

文中针对传统机械限速器动作速度不能跟随轿厢速度、动作速度不精确等问题,提出了机械-电子限速器,在不改变原有机械限速器的基础上增加了电子限速器来改善其性能。文中给出了机械-电子限速器的结构、控制及原理,在此基础上设计了电子限速器的动作方式,给出了高速梯减速区的数据表现分析。

关键词：电子限速器减行程限速器速度跟随高速梯

宝兴陆栖脊椎动物区系的垂直分化及其原因的探讨

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四川大学学报（自然科学版） 1991年第1期28卷 103-108页

作者：张俊范柳辉胡锦矗四川大学生物系四川师范学院

宝兴的91.13％陆生脊椎动物为恒温动物。鸟类季节相与我国东部南北均不相同,川滇及喜马拉雅山地的区系成分多达30.5％.根据其各植被带夏季的陆栖脊椎动物区系的相似率将分别为3个垂直带.探讨各垂直带的动物区系的现状和起源演变后认为:... 详细信息

宝兴的91.13％陆生脊椎动物为恒温动物。鸟类季节相与我国东部南北均不相同,川滇及喜马拉雅山地的区系成分多达30.5％.根据其各植被带夏季的陆栖脊椎动物区系的相似率将分别为3个垂直带.探讨各垂直带的动物区系的现状和起源演变后认为:当地阔叶林带的动物区系的历史和现状与长江中下游地区大致相同;其余则受新构造运动和更新世冰川进退影响较大;生物进化过程的加快使之川滇喜马拉雅山区可能成为某些分类群的次级分布中心.

关键词：陆栖脊椎动物区系垂直分化