（R）evolution in the Food Market-Impact of Retail Internationalization in Transition Countries

The food retail business has undergone a number of structural changes due to increasingly globalized markets and internationalization. Former nationally oriented retailers have suddenly become global. This process also affects new structures in agribusiness, most notably as general retailers export their business models. A comparison of the development and the impact of globalization in the retail sectors of different transition countries reveals varied opportunities for and threats to the participants in agribusiness.     

基于2-DE结合质谱研究围产期奶牛血浆蛋白表达的变化

本试验旨在揭示奶牛围产期免疫功能下降的机理。采用二维凝胶电泳方法建立了分娩前第21天、分娩后第1和21天血浆蛋白表达图谱,SYPRO ruby染色后,ImageMaster 2D platinum 6.0软件匹配检测差异表达蛋白点,液相色谱串联质谱鉴定。结果表明:与分娩前第21天和分娩后第21天相比,分娩后第1天血浆中转甲状腺素蛋白表达量下调、而结合珠蛋白和α1酸性糖蛋白表达量上调;与分娩前第21天和分娩后第1天相比,分娩后第21天载脂蛋白A1表达量增加,这些表达变化的蛋白涉及急性期应答反应及运输和代谢等生物学功能。结果提示奶牛分娩后急性期蛋白表达量的增加可能与免疫功能下降相关。     

FDI溢出与区域技术进步的非线性效应研究

采用考虑“坏”产出的Malmquist-Luenberger指数测算我国全要素生产率，构建面板平滑转换模型研究技术进步与外商直接投资（FDI）之间的非线性关系.研究结果表明，早期经济发展阶段，由于我国与投资国之间的技术差距过大，“FDI技术溢出效应”并未出现，此时FDI不利于技术进步.随着经济逐渐发展，FDI对技术进步的抑制作用逐渐减弱，并开始转为正的促进作用，而当经济发展到门槛值时，促进作用逐渐明显，“FDI技术溢出效应”出现.此外，人力资本和金融发展程度对技术进步的影响也存在门槛效应，其中，人力资本对技术进步的影响最开始为负，然后转为正，而金融发展程度对技术进步的影响最开始为正，然后转为负.     

渔业转型中行为主体间关系的处理

我国渔业正面临着由追求产量向提高质量效益、由规模扩张向提高产业素质、由资源消耗向资源节约和环境友好的转变.在渔业转型过程中,各行为主体特别是渔业企业和个人与有关政府之间的关系如何处理是一个重要的部分.文章在分析了当前渔业行为主体之间的矛盾之后;借鉴目前许多研究学者提出的新观点、新思路,提出选择合适的制度路径,从国家政府到地方政府再到渔民,逐级权利下放以使利益相关者之间相互制约、相互配合,更有效的开展渔业转型策略.     

非对称型缓和曲线测设方法的探讨

通过对缓和曲线性质的分析 ,提出了几种计算非对称型缓和曲线的基本方法与原理 ,并给出设计非对称型缓和曲线的平曲线的要素及曲线主点里程计算方法及现场敷设方法。     

Environmental Factors Governing Soil Water Repellency Dynamics in a Pinus Pinaster Plantation in NW Spain

Soil water repellency (SWR) is a dynamic property that changes throughout the year. The objective of this work was to identify the environmental factors governing the temporal patterns in SWR in a pine plantation in northwest Spain with a view of predicting its occurrence and persistence. For this purpose, 24 samples were collected from the soil surface (0–5 cm) at 25 different times over a 1‐year period and analysed for SWR by using water drop penetration time test and soil moisture measurements. Temporal variations in SWR exhibited a well‐defined seasonal pattern. The soil surface was largely wettable from late autumn to early spring and extremely water repellent during summer and early autumn. Repellency persistence was rather variable during spring. There was highly significant correlation between SWR and soil moisture content. The moisture range defining the presence or absence of repellency under field conditions was 22–57%. There were also significant correlations with the target variables (maximum temperature, minimum temperature, precipitation and water balance during variably long antecedent periods), with coefficients that increased with increasing length of the antecedent period considered. The moisture content of soil at the time of sampling and the average maximum temperature for the 28 days before sampling are the best predictors of occurrence of SWR and its persistence in different seasons. Copyright © 2015 John Wiley & Sons, Ltd.     

温度对光敏感雄性核不育水稻育性转换的影响研究

在北京(N39°56′)自然变温和人工控温条件下分别对比观察光敏感雄性核不育(pgms)水稻的育性对10小时、16(或15)小时两种光周期的反应。试验结果指出: 1.在适宜水稻发育的温度范围内,pgms水稻均有因光周期不同而发生的育性转换。而且光周期效应远大于温度不同所引起的育性变化。 2.温度变化可诱发长日光周期状态下pgms水稻的     

Superconductivity of Single-Walled Carbon Nanotubes

The electric-arc technique used to generate single-walled carbon nanotubes (SWCNTs) is introduced. Especially, the superconductivity of SWCNTS is concerned. The samples of single-walled carbon nanotubes are suspended between two superconducting electrodes and their super-currents may be observed under special conditions. It is called 'proximity-induced method'. With the method, some experiments show that SWCNTs have higher critic super-currents, and the temperature and magnetic field dependence of the critic currents exhibits unusual features.     

GLONASS Transition Between GLONASS and GPS

In this paper, the GLONASS system is introduced, then the coordinates adopted in both GLONASS and GPS are discussed. The authors present a mathematic model of conversion between PZ-90 and WGS-84.This paper lays emphasis on the expounding the solution of converting parameters,then,the converting formula suitable for use in China is also presented. After that, in this paper starting from the converting formula to discuss the WGS-84 ground coordinate system and space-ground coordinate system as well as the PZ-90 space-ground coordinate system and ground coordinate system are discussed.Finally, the data used in China in the process of WGS-84 converting into PZ-90 are analyzed.     

碳达峰背景下遵义市土地利用转型的生态环境效应及预测

[目的]研究土地利用转型的生态环境效应及其发展趋势,为促进土地利用转型、低碳循环发展及实现“双碳”目标提供依据。[方法]基于贵州省遵义市2005,2010,2015,2020年4期的土地利用数据,运用空间分析技术,对该区土地利用转型的生态环境效应及其发展趋势进行研究。[结果](1)2005—2020年土地转型主要表现为碳汇用地之间的相互转换,以及碳汇用地向碳源用地转型。(2)净碳排放量由2005年的5.99×10⁵ t增加到2020年的9.87×10⁶ t,增加了9.27×10⁶ t,增幅达1 548.15%。但增量却呈逐渐减少的趋势,增幅也逐渐降低。(3)遵义市生态系统服务价值量由2005年的7.64×10¹⁰元增加到2020年的7.73×10¹⁰元,呈波动上升趋势,共增加了9.14×10⁸元,增长率为1.2%。(4)通过灰色预测模型得出遵义市未来净碳排放量和生态系统服务价值量会持续增加,且都呈规律上升趋势。[结论]遵义市在生态环境方面仍面临着不小的压力...