三维基因组学概述及其在农业生物育种方面的研究进展          下载免费PDF全文

任妍妍  彭巍  刘贤  赵杨杨  张子敬  付长其  张君  田全召  王二耀  雷初朝  黄永震 《中国牛业科学》2022,48(6):70-75

真核细胞中染色质以不同层次的三维结构有序的折叠在细胞核中,其空间层次结构对基因的表达调控和细胞发挥正常的生理功能都起着重要的作用,在动物育种方面具有很大潜力,但尚未被完全探索。本文介绍三维基因组的结构单元(染色质疆域、A/B 区室、拓扑关联结构域和染色质环)以及研究三维基因组的主要技术,对三维基因组学在农业中的研究进展和应用前景进行了探讨,旨在深入了解三维基因组学的功能和应用前景,以期为生物育种改良提供部分帮助。  相似文献   

甜橙密植果园光合特性研究   总被引：5，自引：2，他引：5  

田世平  欧毅 《西南大学学报(自然科学版)》1991,13(1):42-47

  相似文献   

营林产业发展问题的研究   总被引：1，自引：0，他引：1  

田治威  任恒祺  金虹 《北京林业大学学报》1992,(3)

应用产业政策学说对森林资源的经营管理及以此为基础形成的营林产业进行系统地经济分析,以了解营林产业的实质和产业进程,正确认识营林产业的社会作用、多重意义及其在林业产业链中的基础地位;根据森林资源的现实供给探索营林产业政策中的欠缺,进而开展森林资源的潜在供给和远景供给的趋势研究,预见营林产业供给格局可能的变化和营林产业的发展态势,以期为制定与森林资源需求相适应的、科学的营林产业政策提供一条新的思路.  相似文献   

大容量风力发电机组的设计     

田德 《内蒙古农业大学学报(自然科学版)》1993,(2)

为了浓缩风能,把载有风力机翼的转动箱置入固定翼箱中(参照图1)。本文对扩散管(dif-fuser)作了特殊研究,以高效率的扩散管为设计基础,以内蒙古作为设计对象。由于风被浓缩后利用,地面风速为8m/s 时,风力机处的风速为12.6m/s,此时风力机的输出功率可以达到5180KW。当纵方向5台重叠时,总输出可以达到25MW。因为能达到大功率输出,所以每台风力机可以根据风速大小,用大小两台发电机发电,机组年运转率比其它类型风力发电机组高。  相似文献   

光温敏核不育水稻的育性及花药的发育解剖学研究   总被引：5，自引：0，他引：5  

吴钿  高秀梅  张建中 《西南大学学报(自然科学版)》2002,24(2):138-140

采用形态解剖学的方法比较观察了6个光温敏雄性不育水稻品种的花药发育状况,并从始穗期起抽检花粉育性,结果表明,各不育水稻的雄蕊发育第5期的绒毡层细胞均明显小于对照品种,细胞质也不浓厚;药幅维管束的导管、筛管管腔较小,维管束鞘细胞较小。在花药发育的第8期,药隔维管束的韧皮部和木质部的界限仍不明显,药壁较厚。  相似文献   

仔猪疑后核和疑核及面后核的形态与构筑          下载免费PDF全文

穆祥  田九畴 《西北农林科技大学学报(自然科学版)》1988,(4):41-44

用仔猪脑干制成低粘度硝化棉连续切片,以Nissl法染色,光镜观察。结果表明:①疑后核居延髓尾侧部相当于脊髓中间外侧柱的位置。核往呈锥形,锥底朝前接疑核。细胞疏密不匀,小细胞多在后部,中等细胞多在前部,大细胞散布于中、小细胞之中。②疑核前部轮廓不清,主要由中、小细胞组成。后部的背内侧部主要由大细胞组成;腹外侧部主要由聚集成团的小细胞组成。③面后核在面神经核后方,由中等细胞组成背、腹二密集的细胞群。  相似文献   

微机继电保护的研究现状及展望   总被引：1，自引：0，他引：1  

田有文  宋涛  李季 《沈阳农业大学学报》2002,33(3):219-222

对微机继电保护硬件中的处理器和数据采集系统的研究现状作了阐述。以及对软件中的传统算法和新算法作了综述。并讨论今后微机继电保护的发展趋势。  相似文献   

School food environments and the obesity issue: content,structural determinants,and agency in Canadian high schools     

Anthony Winson 《Agriculture and Human Values》2008,25(4):499-511

To understand the phenomenon of the rapidly increasing prevalence of overweight and obese children and youth, it is especially important to examine the school food environment, the role of structural factors in shaping this environment, and the resulting nutrition and health outcomes. The paper examines research on school food environments in the US and Canada. It notes evidence of widespread availability of poor nutrition products in both environments and delineates reasons for the situation, and examines initiatives presently being undertaken in a number of jurisdictions in both countries to encourage healthy eating in schools. Empirical data are presented from a pilot study of high schools in the Canadian province of Ontario. The study documents the extent of student purchasing of nutrient-poor foods and beverages, and the structural factors internal and external to the school that appear responsible for the availability of such products in food environments in this critical institutional sphere. The paper also examines positive local initiatives in high schools that seek to encourage healthy eating in schools.

Anthony WinsonEmail:

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Anthony Winson PhD   is a professor in the department of sociology and anthropology at the University of Guelph. He has written on agriculture, food and rural development, and restructuring issues related to Canada and the Third World for more than 20 years. Among his books are The Intimate Commodity: Food and the Development of the Agro-Industrial Complex in Canada (Garamond 1993) and, more recently, Contingent Work, Disrupted Lives (University of Toronto 2002, with Belinda Leach) which examines economic restructuring, the changing world of work, and the factors underlying sustainability in small manufacturing-dependent rural communities in several regions of Ontario. This book won the John Porter Book Prize of the Canadian Sociology and Anthropology Association for 2003. Dr. Winson’s current work is focused on the analysis of factors shaping the contemporary Canadian food environment and their role in producing what has been termed the “epidemic of obesity.” Particular attention is being paid to supermarkets and schools as part of broader-ranging research on the political economic context of the food environment.  相似文献   

Gate-variable optical transitions in graphene     

Wang F  Zhang Y  Tian C  Girit C  Zettl A  Crommie M  Shen YR 《Science (New York, N.Y.)》2008,320(5873):206-209

Two-dimensional graphene monolayers and bilayers exhibit fascinating electrical transport behaviors. Using infrared spectroscopy, we find that they also have strong interband transitions and that their optical transitions can be substantially modified through electrical gating, much like electrical transport in field-effect transistors. This gate dependence of interband transitions adds a valuable dimension for optically probing graphene band structure. For a graphene monolayer, it yields directly the linear band dispersion of Dirac fermions, whereas in a bilayer, it reveals a dominating van Hove singularity arising from interlayer coupling. The strong and layer-dependent optical transitions of graphene and the tunability by simple electrical gating hold promise for new applications in infrared optics and optoelectronics.  相似文献   

发展非公有制林业促进林业可持续发展     

田军 《国家林业局管理干部学院学报》2006,5(2):18-20

作为国民经济的重要基础产业,林业的可持续发展在国民经济可持续发展中起着不可替代的作用.实现林业可持续发展的目标,只靠国家的投入是不够的,必须把全社会的智慧和力量凝聚起来,由部门办林业向社会办林业转变,发展非公有制林业是实现林业可持续发展的必然选择.  相似文献