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耦合形变—扩散对蠕动传播事件引起的水位变化的影响

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华北地震科学 1986年第S1期 103-118页

作者： e.Roeloffs j.W.Rudnickl 周清良河北省地震局

本文利用线性弹性饱水多孔介质中平面应变剪切位错以速度V平隐运动时产生孔隙压力的耦合形变-扩散解,研究了与间歇性蠕动有关的井水位变化。对于大的Vr/2c（其中r是距位错的距离、c是扩散率）,其解接近于Wesson（1981）分析由蠕动事件... 详细信息

本文利用线性弹性饱水多孔介质中平面应变剪切位错以速度V平隐运动时产生孔隙压力的耦合形变-扩散解,研究了与间歇性蠕动有关的井水位变化。对于大的Vr/2c（其中r是距位错的距离、c是扩散率）,其解接近于Wesson（1981）分析由蠕动事件引起的水位变化所使用的去耦弹性解的形式。这两个解之间的差在距断层平面10个扩散长度内（20c/V）是显著的。更准确地说,耦合解预示着位错后面的孔隙压力改变符号,并在数量上比去耦解预期的要小的多。对于泊松比是0.3、Skempton系数为0.8以及剪切模量为30GPa的非泄漏介质,在V=1公里/天、C=1.0米2/秒时,耦合解预示每滑动一毫米,最大孔隙压力变化13.7kPa（173毫巴）。耦合解的频谱被限制在一个中心值与V成正比和与从观测点到断层的距离大约成反比的频带上。因此,接近断层平面,耦合解占用的频带可能超过了水井反应的范围。耦合解能用来解释johnson（1973）观测到的和由Wesson（1981）用去耦解模拟的同一与蠕动有关的水位变化。尽管在岩石材料特性和蠕动事件速度方面存在着不确定性,但耦合解预报的水位变化在幅度上可与实际观测到的变化相比。

关键词：水位变化去耦断层观测点地质构造孔隙压力断层面形变

evolutionary Genomics of Plant Gametophytic Selection

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Plant Communications 2020年第6期1卷 18-33页

作者： Felix e.G.Beaudry joanna L.Rifkin Spencer C.H.Barrett Stephen I.Wright Department of ecology and evolutionary Biology The University of Toronto25 Willcocks StreetTorontoON M5S 3B2Canada These authors contributed equally to this article

It has long been recognized that natural selection during the haploid gametophytic phase of the plant life cycle may have widespread importance for rates of evolution and the maintenance of genetic *** theoretical advances have further highlighted the significance of gametophytic selection for diverse evolutionary *** approaches offer exciting opportunities to address key questions about the extent and effects of gametophytic selection on plant evolution and ***,we review the progress and prospects for integrating functional and evolutionary genomics to test theoretical predictions,and to examine the importance of gametophytic selection on genetic diversity and rates of *** is growing evidence that selection during the gametophyte phase of the plant life cycle has important effects on both gene and genome evolution and is likely to have important pleiotropic effects on the *** discuss the opportunities to integrate comparative population genomics,genome-wide association studies,and experimental approaches to further distinguish how differential selection in the two phases of the plant life cycle contributes to genetic diversity and adaptive evolution.

关键词： gametophyte pollen ovule evolution genomics selection

Identification of a novel pathway involving a GATA transcription factor in yeast and possibly in plant Zn uptake and homeostasis

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journal of Integrative Plant Biology 2014年第3期56卷 271-280页

作者： Matthew j.Milner Nicole S.Pence jiping Liu Leon V.Kochian Robert W.Holley Center for Agriculture and Health USDA‐ARS Cornell University Department of Plant Biology Cornell University

To gain a better understanding of the regulation of Zn homeostasis in plants and the degree of conservation of Zn homeostasis between plants and yeast, a cDNA library from the Zn/Cd hyperaccumulating plant species, Noccaea caerulescens, was screened for its ability to restore growth under Zn limiting conditions in the yeast mutant zaplA. ZAP1 is a transcription factor that activates the Zn dependent transcription of yeast genes involved in Zn uptake, including ZRT1, the yeast high affinity Zn transporter. From this screen two members of the e2F family of transcription factors were found to activate ZRT1 expression in a Zn independent manner. The activation of ZRTI by the plant e2F proteins involves e2F- mediated activation of a yeast GATA transcription factor which in turn activates ZRT1 expression. A ZRT1 promoter region necessary for activation by e2F and GATA proteins is upstream of two zinc responsive elements previously shown to bind ZAP1 in ZRT1. This activation may not involve direct binding of e2F to the ZRT1 promoter. The expression of e2F genes in yeast does not replace function of ZAP1; instead it appears to activate a novel GATA regulatory pathway involved in Zn uptake and homeostasis that is not Zn responsive.

关键词： e2F transcription factor GATA transcription factor ZRT1 Znhomeostasis

Anisotropic inversion of traveltimes and polarizations of wide-angle seismic data using simulated annealing

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Anisotropic inversion of traveltimes and polarizations of wi...

中国科学院地质与地球物理研究所2006学术年会

作者： Chen,j.Y.,Zhang,Z.j.and Liu,e. Key Laboratory of Lithosphere evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences, Beijing 100029,China

We present a joint inversion scheme for traveltime and polarization information of wide-angle seismic data to determine three of the five anisotropic parameters(vertical P-wave velocity VPO and Thomsen’s parameters e and d) in transversely isotropic media with a vertical symmetry axis(VTI).Our inversion scheme is based on a simulated annealing(SA) optimization *** first present our SA-based inversion scheme involving four steps and then give details about the choices of SA *** data are used to test the effectiveness of our inversion method for kinematic(traveltime) and dynamic(polarization) *** comparison of the joint inversion results with those based only on traveltimes or polarizations demonstrate that the joint inversion scheme can provide much better constraints to the anisotropic ***,we apply the inversion scheme to real wide-angle three-component seismic data acquired in the southeast China to obtain 1D crustal velocity and anisotropic structures.

关键词： anisotropy inversion wide-angle data simulated annealing

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现代船用柴油机润滑油及其发展(一)

柴油机 1984年第4期 11-19页

作者： F.j.Thomas G.e.Hold 钱伯章

船用柴油机船用柴油机的分类见表1。低速、直接传动、二冲程、十字头式柴油机,它们的工作转速在90～150转/分。现在设计的转速更低,这是为了通过提高螺旋桨效率来改善燃料的经济性。这些发动机的输出功率为每缸700～4,000马力,单机功率... 详细信息

船用柴油机船用柴油机的分类见表1。低速、直接传动、二冲程、十字头式柴油机,它们的工作转速在90～150转/分。现在设计的转速更低,这是为了通过提高螺旋桨效率来改善燃料的经济性。这些发动机的输出功率为每缸700～4,000马力,单机功率可达48,000马力。业已表明,两级涡轮增压的柴油机,每缸输出功率可达6,700马力。

关键词：润滑油含硫量活塞环磨损总碱值船用气缸油

Influence of Adjuvants on the Control of Glyphosate-Resistant Canada Fleabane and Waterhemp in Corn with Tolpyralate

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American journal of Plant Sciences 2020年第3期11卷 354-371页

作者： Nicole M. Langdon Nader Soltani Alan j. Raedar David C. Hooker Darren e. Robinson Peter H. Sikkema University of Guelph Ridgetown Campus Ridgetown Canada

Tolpyralate is a new benzoylpyrazole herbicide for weed management in corn. It is recommended to be co-applied with atrazine along with the adjuvants methylated seed oil concentrate (MSO) plus an ammonium nitrogen fertilizer, such as urea ammonium nitrate (UAN). Two studies were conducted on glyphosate-resistant (GR) Canada fleabane and GR waterhemp to determine if an additional adjuvant is still required when tolpyralate plus atrazine are tankmixed with a commercial glyphosate formulation (Roundup WeatherMAX®) in corn. Trials were conducted over a two-year period (2018-19) on farms in south western Ontario with confirmed GR populations. When co-applied with Roundup WeatherMAX®, the addition of MSO to tolpyralate + atrazine increased control of GR waterhemp 9%;however, there was no increase in GR Canada fleabane control from the addition of additional adjuvants. At 8 WAA, all treatments provided > 91% and > 84% control of GR waterhemp and GR Canada fleabane, respectively. This study concludes that the addition of Roundup WeatherMAX®to tolpyralate plus atrazine improves the control of GR waterhemp and GR Canada fleabane in corn.

关键词： Biomass Crop Injury Density Sensitivity Weed Control Yield Amaranthus tuberculatus Conyza canadensis L. Cronq

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editorial

CCS Chemistry 2024年第9期6卷 266-270页

作者： Zhang Xi Minton Donna j 机构不详

“Our responsibility is to do what we can,learn what we can,improve the solutions,and pass them on.”—Richard ***,Nobel Laureate in Physics(1918–1988)With january behind us,we are well into 2024 and life has fallen back into its familiar *** is resuming,and students and professors alike are back in the lab and *** China,there is buzzing excitement for the Spring Festival and coming of the Year of the Dragon on February *** is said that,“龙行龘龘,前程朤朤”or“The dragon strides forward with determination,and the future is bright.”We have much to look forward to in the coming months.

关键词： has dragon Nobel

Metformin improves boar sperm quality via 5′-AMPactivated protein kinase-mediated energy metabolism in vitro

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Zoological Research 2020年第5期41卷 527-538页

作者： Rong-Nan Li Zhen-Dong Zhu Yi Zheng Ying-Hua Lv Xiu-e Tian De Wu Yong-jun Wang Wen-Xian Zeng Key Laboratony for Anima/Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYanglingShaanxi 712100China Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of education of China Institute of Animal NutntionSichuan Agricultural UniversityChengduSichuan 611100China

Sperm are specialized cells that require adenosine triphosphate(ATP) to support their *** sperm energy homeostasis in vitro is vitally important to improve the efficacy of boar sperm preservation. Metformin can activate 5′-AMPactivated protein kinase(AMPK) to improve metabolic flexibility and maintain energy homeostasis. Thus, the aim of the present study was to investigate whether metformin can improve boar sperm quality through AMPK mediation of energy metabolism. Sperm motility parameters, membrane integrity,acrosomeintegrity,mitochondrial membrane potential(ΔΨm), ATP content, glucose uptake,and lactate efflux were *** and expression levels of AMPK and phospho-Thr172-AMPK(p-AMPK) were also detected by immunofluorescence and western blotting. We found that metformin treatment significantly increased sperm motility parameters, ΔΨm, and ATP content during storage at 17 ℃. Moreover, results showed that AMPK was localized at the acrosomal region, connecting piece, and midpiece of sperm and p-AMPK was distributed at the post-acrosomal region, connecting piece, and midpiece. When sperm were incubated with metformin for 4 h at 37 ℃, sperm motility parameters, ΔΨm, ATP content,p-AMPK, glucose uptake, and lactate efflux all significantly increased, whereas the addition of Compound C treatment, an inhibitor of AMPK,counteracted these positive effects. Together, our results suggest that metformin promotes AMPK activation, which contributes to the maintenance of energy hemostasis and mitochondrial activity,thereby maintaining boar sperm functionality and improving the efficacy of semen preservation.

关键词： Metformin AMPK Sperm energy metabolism Glycolysis

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低信噪比条件下锁相环的分析与实验结果

无线电工程 1974年第2期 37-51页

作者： e.j.CHSRLeS W.C.LINDSeY 张毅

1.引言精确地分析存在噪声时二阶锁相环的性能目前仍是然数学难题,所以相位相关通讯系统的设计多半还要依据线性或准线性锁相理论。然而,在空间通讯方面,一些耗费巨资的特殊任务需要应用精确的非线性锁相环理论。而这一理论应能用于在... 详细信息

1.引言精确地分析存在噪声时二阶锁相环的性能目前仍是然数学难题,所以相位相关通讯系统的设计多半还要依据线性或准线性锁相理论。然而,在空间通讯方面,一些耗费巨资的特殊任务需要应用精确的非线性锁相环理论。而这一理论应能用于在发射前预示直到任务结束时止的通信系统的性能。近几年来,已有了几种分析存在噪声时锁相环性能的方法。本文不详述锁相理论的历史与演变,有兴趣的读者可参阅参考文献。但总而言之,迄今为

关键词：锁相环累积分布相位误差时间间隔分布跳周方程实验结果环路滤波器概率分布近似解噪声带宽环路参数