猪体细胞克隆技术研究进展

克隆不仅可以保护濒危动物,而且与干细胞工程技术结合应用于克隆性治疗,具有重大的科学意义和应用价值。体细胞克隆猪因其在人类器官移植方面具有巨大的应用潜力,已成为当今研究的热点,但是体细胞核移植技术仍存在许多问题,其中最主要的是体细胞核移植的环节多,克隆效率低。对体细胞克隆猪的关键环节,即供核细胞、卵母细胞、显微操作、克隆胚的激活、培养及移植技术进行了简要综述。     

福建三明市新型农业生产性服务业发展对策

新型农业生产性服务业是农业社会化服务体系建设的重要方面,也是现代农业发展的必然要求.作为福建内陆山区的三明市,新型农业生产性服务业发展虽有一些亮点,但也面临不少困难与问题.发展多主体、多形式和多功能的新型农业生产性服务业体系,将有助于农业由单纯的第一产业向一、二、三产业协调发展转变.     

应对经济挑战 又好又快发展 更要六盘山精神

适逢机遇、面临挑战的关键时期,为了促进本土经济和社会的稳步、健康发展,大力倡导、积极弘扬不到长城非好汉的六盘山精神,更加有必要认真探讨其深刻内涵和实质,铸造精神高地,以顺应民心和形势的召唤;更应进一步打造固原人民团结奋斗的思想精神支柱,进一步激发全市各族干部群众干事创业的激情和创造力,充分调动各方面的积极因素,形成奋发向上的精神力量和昂扬斗志,凝聚人心,共渡难关,为固原跨越式发展、长足发展提供奋勇争先的精神食粮和强大的精神动力,既具有紧要的现实意义,又具有深远的历史意义。     

人类可持续发展与废弃资源再资源化

人类可持续发展，既满足当代人的需要，又不对后代人满足其需要构成危害的发展。人类可持续发展面临自然生态环境恶化和自然资源短缺的困扰。本文在理论上阐述了废弃资源再资源化的实质是自然资源循环经济利用的同时，从实践上论述了废弃资源再资源化是保护自然生态环境、缓解自然资源短缺、实现人类可持续发展的有效途径，并从我国基本国情出发，对废弃资源再资源化提出了可行性的综合对策措施。     

Sexual transmission and propagation of SIV and HIV in resting and activated CD4+ T cells

In sexual transmission of simian immunodeficiency virus, and early and later stages of human immunodeficiency virus-type 1 (HIV-1) infection, both viruses were found to replicate predominantly in CD4(+) T cells at the portal of entry and in lymphoid tissues. Infection was propagated not only in activated and proliferating T cells but also, surprisingly, in resting T cells. The infected proliferating cells correspond to the short-lived population that produces the bulk of HIV-1. Most of the HIV-1-infected resting T cells persisted after antiretroviral therapy. Latently and chronically infected cells that may be derived from this population pose challenges to eradicating infection and developing an effective vaccine.     

International research: its role in environmental biology

To determine the role of environmental factors in human health, studies on several population groups are essential, involving the most sophisticated techniques possible. The logistic and political problems associated with such studies, especially in developing countries, and the high cost of modern environmental biological investigations make it particularly desirable to avoid unnecessary duplication and waste of resources. For certain investigations an international research center would appear to have considerable advantages, provided that the organizational difficulties can be overcome. Not only can such an organization provide the human data necessary for calculating the balance between the benefits and harm of a given course of action but also it may stimulate the long-term routine laboratory studies so necessary as a basis for extrapolation from animals to man.     

昆虫种群生命系统研究的状态方程

应用状态空间法研究系统的控制,不仅有利于把系统划分为若干组分或子系统对各种因子分别进行动态描述,同时更好地解决多输入和多输出的研究技术,因而有可能成为种群生命系统控制研究的重要手段。本文拟通过网络模型着重讨论适应于昆虫种群研究的状态空间方程的建立问题。     

硒在动植物及微生物体中的转化规律研究进展

我国低硒地区占国土总面积的72%,其中严重缺硒地区的粮食等天然食物硒含量较低,当地人因无法从食物中摄取足够硒而罹患多种疾病。因此,通过科学手段有效解决我国人体缺硒问题意义非凡。植物性食物是动物和人体碳水化合物及矿物质等营养的重要来源,植物吸收环境中的硒,并将其转化为有机态硒,之后通过食物链为人体吸收利用,这是一种安全有效的缓解人体硒摄入匮乏的途径。植物生长过程中所需的矿物质营养大多都来自于土壤,微生物作为土壤中广泛存在的一种生物,不仅在植物促生方面发挥着重要作用,而且还可通过生物活化等作用,将土壤中的硒转化为有利于植物吸收的形态,进而提高植物对硒的利用率。本文综述了目前关于动物、植物、微生物对硒转化利用规律方面的研究进展,以期为今后通过微生物介导途径,提高植物吸收转化环境硒的效率,改善动物及人体缺硒状况,进而解决缺硒地区人体健康问题提供有价值的参考信息。     

农村体育可持续发展路径构建研究——基于江西赣南的实证分析

农村体育是我国体育发展的薄弱环节,在当前新农村建设与新型城镇化并进的社会环境下,农村体育既面临发展的机遇,也受到严峻的挑战。在论述农村体育可持续发展内涵基础上,以经济欠发达的赣南革命老区农村体育为例,对农村体育可持续发展路径进行了探索性的构建,希望为农村体育的可持续发展提供参考。     

Autonomic nervous system activity distinguishes among emotions

Emotion-specific activity in the autonomic nervous system was generated by constructing facial prototypes of emotion muscle by muscle and by reliving past emotional experiences. The autonomic activity produced distinguished not only between positive and negative emotions, but also among negative emotions. This finding challenges emotion theories that have proposed autonomic activity to be undifferentiated or that have failed to address the implications of autonomic differentiation in emotion.     

健全农村土地流转市场的困境与政府行为分析

一个统一、规范、有序的土地流转市场,是农村土地承包经营权流转健康发展的保障,也是实现农村土地生产力诸要素合理配置和适度规模经营以及统筹城乡经济发展的载体。当前,农村土地流转市场的健全还存在着复杂的制约因素,面临诸多困境。土地流转应是不同市场主体之闻要素配置的一个过程,不应是政府行为,政府在健全农村土地流转市场的进程中,应明确角色定位体现其宏观管理和微观服务的职能。     

马克思、恩格斯的全球化思想与社会主义中国

全球化是当今时代的重要特征之一，是世界历史发展的必然趋势。而这种全球化趋势最早是由马克思、恩格斯提出的。在马克思、恩格斯看来，全球化思想包括世界历史理论和全球社会主义、共产主义理论。全球化是一把双刃剑，它既给社会主义国家带来了发展的机遇，又带来了严峻的挑战。面对全球化浪潮的冲击，社会主义中国不应该回避，而应该抓住机遇，迎接挑战，深化发展，努力开创建设有中国特色社会主义的新局面     

From pedigree cats to fluffy-bunnies

We consider two distinct classes of quantum mechanical entanglement. The first "pedigree" class consists of delicate highly entangled states, which hold great potential for use in future quantum technologies. By focusing on Schrodinger cat states, we demonstrate not only the possibilities these states hold but also the difficulties they present. The second "fluffy-bunny" class is made up of robust states that arise naturally as a result of measurements and interactions between particles. This class of entanglement may be responsible for the classical-like world we see around us.     

Presymptomatic detection of prions in blood

Prions are thought to be the proteinaceous infectious agents responsible for transmissible spongiform encephalopathies (TSEs). PrP(Sc), the main component of the infectious agent, is also the only validated surrogate marker for the disease, and its sensitive detection is critical for minimizing the spread of the disease. We detected PrP(Sc) biochemically in the blood of hamsters infected with scrapie during most of the presymptomatic phase of the disease. At early stages of the incubation period, PrP(Sc) detected in blood was likely to be from the peripheral replication of prions, whereas at the symptomatic phase, PrP(Sc) in blood was more likely to have leaked from the brain. The ability to detect prions biochemically in the blood of infected but not clinically sick animals offers a great promise for the noninvasive early diagnosis of TSEs.     

VMware虚拟化技术在科研院所数据中心建设中的探索与应用

本文主要介绍运用VMware虚拟化技术,对科研院所数据中心服务器进行虚拟化布署。结果表明,VMware虚拟化技术的应用,不但降低了信息化管理难度与后期硬件投入,而且提高了数据中心管理效率与信息化水平。     

Improved and safer nuclear power

Recent progress in advanced nuclear power development in the United States is revealing high potential for nuclear reactor systems that are smaller and easier to operate than the present generation. Passive, or intrinsic, characteristics are applied not only to provide inherent stability of the chain reaction but also to ensure continued cooling of the fuel and its containment systems even if a major breakdown of the normal cooling and control functions were to occur. The chance of a severe accident is thereby substantially reduced. The plant designs that are emerging are simpler and more rugged, have a longer life span, and place less burden on equipment and operating personnel. Modular design concepts and design standardization are also used to reduce construction time and engineering costs, giving promise that the cost of generating power from these systems will be competitive with alternative methods.     

Several Strategic Issues in the Development of China‘s Seed Industry

Chinese agricultural industry and rural economy are currently undergoing a strategic restructuring. The Seed Act has been thoroughly enforced. The Development of West China program has also got started in an all-round way. Not long ago China entered the World Trade Organization. All these not only present great opportunities but also severe challenges to China. 　　……     

“教、学、做、评”一体化教学模式的机制研究与实践

随着计算机科学技术的飞速发展,计算机专业教学面临着新的考验.本文从计算机专业教学现状进行分析,提出了“教、学、做、评”四位一体教学模式的必要性,并指出了具体的实施条件和实施过程.它有利于促进课程的建设和改革,并且能提高学生的实际动手能力,进而满足当今社会对应用型人才的需求.     

宜昌柑橘罐头产业的现状及发展对策

较为全面地概括了宜昌地区外向型柑橘罐头产业的现状,并深入分析了宜昌地区外向型柑橘罐头产业发展所面临的困难和挑战,在此基础上提出了加快发展宜昌外向型柑橘罐头产业的对策和建议。     

基于线控技术的工程机械转向系统的研究

针对工程机械转向系统面临的问题和难点,提出了一种基于线控转向技术的新型转向系统。该系统采用高速开关阀组控制流量放大阀。介绍了该系统的组成、工作原理和控制原理。采用Matlab与AMEsim软件对系统进行了联合仿真实验。实验结果表明:该系统继承了全液压转向系统的随动特性,具有良好的响应速度和控制精度。