首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 314 毫秒
1.
生物系统的科学与工程是整合系统论、实验、计算和工程方法的交叉学科研究与应用.系统生物学、系统医学,建立在系统科学和数学模型基础上,采用分子、组学生物技术和计算、生物信息技术,以及基因合成与转基因生物技术等研究生物系统原理和规律.系统遗传学与系统生物技术是研究天然与人工生物系统的基因系统与蛋白质系统构成细胞的软件信息与硬件运行系统的机理与方法.合成生物学、系统生物工程也是建立在系统科学和数学模型基础上,应用于生物系统原理设计虚拟计算机信息软件和仿生人工机器硬件、人造工程生物体和基因信息系统等.  相似文献   

2.
自1976年美国首次发现军团病以来,人们意识到军团菌危害,并开始认识它的病原学及其致病原理等。国内外调查研究均表明,空调系统军团菌的污染情况已相当严重,且目前还没有有效的军团菌疫苗预防军团病,空气传播也使切断传播途径的措施难以实现,在流行病学上控制军团病发生的可行方案只有加强可能被污染水源的管理。因此,采用控制污染来源、加强卫生检测和采用有效的物理与化学消毒处理手段就显得尤为重要。为此,就公共场所空调系统中军团菌污染现状与控制措施作一综述。  相似文献   

3.
集中空调系统常常是病菌、病毒滋生和繁殖的温床,是传染病交叉感染和传播的渠道,根据《公共场所集中空调通风系统卫生规范》的要求,从2005年到2007年,动态检查了大连市部分集中空调使用单位,对集中空调通风系统及冷却塔冷却水进行了检测分析。  相似文献   

4.
阐述医院检验危急值预警防控系统的设立及运行模式,通过科学遴选预警项目、构建信息化平台、建立临床反馈机制等措施,优化系统流程设计。分析评价预警防控系统的运行效果,指出系统紧贴临床实际,缩短检验结果的周转时间,有效降低医疗风险,对提高医疗质量和管理水平起到重要的促进作用。  相似文献   

5.
系统生物科学最早开创于贝塔郎菲的理论生物学和一般系统论。系统生物科学或生物系统科学研究分子、细胞、器官和群体各层次的生物系统,尤其是心智和遗传的信息系统。系统生物工程(曾邦哲1994年)采用实验分析和系统逻辑的双重方法论,探索改造和仿造生物系统的工程技术,包括:1)生化工程、生态工程,2)生物反应器、遗传工程,3)高分子传感器、仿生工程,4)生物遗传计算、智能工程等领域,将促进系统医学、转基因生物反应器、生物计算机、智能机器人和中医药现代化的发展。现代城市生态、工业网络的系统藕合、循环、再生的无污染、无烟化工业生态工程将带来自然、工业、人文之间的和谐。  相似文献   

6.
草地农业生态系统中的系统耦合与系统相悖研究动态   总被引:12,自引:3,他引:12  
林慧龙  侯扶江 《生态学报》2004,24(6):1252-1258
综述了草地农业生态系统中系统耦合与系统相悖的内涵及其发展过程 ,该领域的研究前沿与发展趋势。草地农业生态系统的种间耦合、不同生产层之间的纵向耦合、不同草地农业生态系统之间的横向耦合、系统的界面过程与系统耦合、生物的时间地带性与系统耦合是草地农业生态系统中的系统耦合与系统相悖理论与实践研究的 5个前沿领域。对系统相悖量化工作将是今后系统耦合、系统相悖理论研究的关键 ,综合运用多种非线性科学方法解决草地农业生态系统的系统耦合和系统相悖的数量化工作可能是系统耦合和系统相悖理论研究和实践的一个非常有前途的方向。  相似文献   

7.
人眼房水动力学系统的建模与仿真方法研究   总被引:1,自引:0,他引:1  
为从宏观上应用工程方法进一步研究房水运行机理,提出了人眼前节房水流动系统的动力学仿真模型。依据目前眼科界较为公认的房水运行和眼压反馈机制建立系统构架,基于对眼科解剖学与生理学相关理论的分析、流体力学基本原理和临床参数进行系统辨识与参数确定。运用数字仿真的方法分剐在正常生理平稳状况和激发试验状况下对模型进行了仿真运行,获得了和临床结论较为一致的结果。能较好地模拟房水运行机制,在与临床可测量参数一致的同时能获得一些不易测量的参数,为研究房水动力学提供依据。  相似文献   

8.
系统及系统模型是科学教育高度关注的跨学科概念之一,它体现了人们认识复杂世界的方式。系统是根据研究目的人为界定的,它是有关联的物体或元件组成的有秩序整体,包含边界、组分及组分间的相互作用。其中组分与相互作用的总和作为系统的结构,与系统的功能之间互为因果。系统模型是描述和理解系统的有效工具,它根据研究目的对系统进行了必要的假设和近似,以突出系统的本质特征,但这些假设和近似会影响到系统模型的可信度和准确度。在基础教育理科课堂中以系统模型作为认知工具,并对系统及系统模型概念进行外显化的教学,将促使学生深入理解学科知识,提升课堂教学的质量。  相似文献   

9.
王佳文  何萍  徐杰  丁森 《应用生态学报》2021,32(3):1129-1140
水生态系统中宇宙指人工构建的河流、湖泊、湿地、海洋等水生态系统近自然模拟装置,可以控制一定的物理、化学要素和生境条件,开展生物群落响应研究。中宇宙实验可以弥补传统实验室小型装置模拟要素过于简单,而野外现实系统复杂不可控制和难以开展对比实验的局限。本文列举了当前国际上多个科研机构长期运行的水生态系统中宇宙,将其归纳为流水型中宇宙、围隔装置、陆基模拟池、移动式水槽4类,各类中宇宙一般包括物理-生物模拟系统、自动调控系统、监测分析系统、中央控制系统。近年来,我国水生态系统的研究逐渐从单一环境要素向生态系统整体转变,对中宇宙模拟实验的需求愈加迫切。建议我国水生态系统中宇宙建设应提高结构复杂性,并与野外现场监测相结合,共同支撑更大尺度系统的整体模拟。  相似文献   

10.
实验动物屏障系统利旧改造及环境控制效果分析   总被引:1,自引:0,他引:1  
对使用年限超过5年的实验动物屏障系统进行利旧改造,并分析改造后的环境控制效果。在原有基础上对实验动物屏障的排风、空调、土建、监控系统等进行了利旧改造,改造后各项环境指标均符合规范要求,且稳定性得到了很好改善,能耗及故障发生频率显著降低。KM小鼠、SD大鼠繁殖性能均有所增强,饲料利用率提高。在实验动物屏障系统改造过程中将利旧、新技术运用与实现微环境控制进行有机结合,使屏障系统长期高效运转并确保实验动物生产质量。  相似文献   

11.
We are flat-faced hominins with an external nose that protrudes from the face. This feature was derived in the genus Homo, along with facial flattening and reorientation to form a high nasal cavity. The nasal passage conditions the inhaled air in terms of temperature and humidity to match the conditions required in the lung, and its anatomical variation is believed to be evolutionarily sensitive to the ambient atmospheric conditions of a given habitat. In this study, we used computational fluid dynamics (CFD) with three-dimensional topology models of the nasal passage under the same simulation conditions, to investigate air-conditioning performance in humans, chimpanzees, and macaques. The CFD simulation showed a horizontal straight flow of inhaled air in chimpanzees and macaques, contrasting with the upward and curved flow in humans. The inhaled air is conditioned poorly in humans compared with nonhuman primates. Virtual modifications to the human external nose topology, in which the nasal vestibule and valve are modified to resemble those of chimpanzees, change the airflow to be horizontal, but have little influence on the air-conditioning performance in humans. These findings suggest that morphological variation of the nasal passage topology was only weakly sensitive to the ambient atmosphere conditions; rather, the high nasal cavity in humans was formed simply by evolutionary facial reorganization in the divergence of Homo from the other hominin lineages, impairing the air-conditioning performance. Even though the inhaled air is not adjusted well within the nasal cavity in humans, it can be fully conditioned subsequently in the pharyngeal cavity, which is lengthened in the flat-faced Homo. Thus, the air-conditioning faculty in the nasal passages was probably impaired in early Homo members, although they have survived successfully under the fluctuating climate of the Plio-Pleistocene, and then they moved “Out of Africa” to explore the more severe climates of Eurasia.  相似文献   

12.
Volatile organic compounds from Penicillium viridicatum and Methylobacterium mesophilicum growing on laboratory media and on component materials of automobile air conditioners were analyzed with gas chromatography and mass spectrometry. P. viridicatum produced compounds such as 4-methyl thiazole, terpenes and alcohols, whereas M. mesophilicum produced dimethyl disulfide, dimethyl trisulfide, and chlorophenol with growth on laboratory media. In comparison with laboratory media, fewer volatiles were detected from colonized foam insulation materials. Biofilms of M. mesophilicum on aluminum evaporator components produced mainly dimethyl disulfide. These biofilms, after inoculation with P. viridicatum, produced offensive smelling alcohols and esters such as 2-methyl propanol, 3-penten-2-ol, and the ethyl ester of butanoic acid. The moisture and substrates innate to the automobile air conditioning systems provided an environment suitable for microbial biofilm development and odor production. Reduction of retained moisture in the air conditioning system coupled with use of less susceptible or antimicrobial substrates are advised for remediation of the noxious odors. Received: 26 February 2000 / Accepted: 2 May 2000  相似文献   

13.
Twelve automobile air conditioner systems from six manufacturers and three countries, selected mostly because of complaints of unpleasant odors in the passenger compartment, were examined for microbial growth by direct microscopy and enrichment culture. Mixed populations of fungi and bacteria (with occasional protozoa) were observed in biofilms in at least some of the components from all used units. The aluminum heat exchanger fins from ten evaporators demonstrated bacterial biofilms that yielded Methylobacterium mesophilicum. Penicillium viridicatum colonized components from four units. These bacteria and fungi were recoverable repeatedly from these units during ‘dry’ storage of up to 27 months. This report associates a bacterial-fungal community with disagreeable air quality in some automobiles. Received: 24 March 1999 / Accepted: 13 April 1999  相似文献   

14.
目的:监测西安地铁2号线车站内站厅与站台积尘量、细菌总数、真菌总数、PM10、β-溶血性链球菌、新风量、嗜肺军团菌状况。方法:用普通琼脂培养皿和血培养皿分别采集站厅、站台真菌总数、β-溶血性链球菌;用无纺布采集风管内积尘量;利用智能粉尘检测仪采集PM10;利用热球式风速仪采集风口风速求平均风速计算新风量、利用500 mL无菌瓶采集冷却水和冷凝水检测嗜肺军团菌。结果:除冷却水中检出嗜肺军团菌外,其他各项指标符合国家相关标准,总体上西安地铁站中央空调卫生学项目及新风量状况较好。结论:按照卫生学预评价意见,健全卫生管理制度,完善必要的卫生设施,使运营过程中产生的各种影响乘客健康的因素得到有效控制、减轻或消除,从公共场所卫生学角度评价该项目是可行的。  相似文献   

15.
16.
Conditioning in Drosophila melanogaster   总被引:2,自引:0,他引:2  
  相似文献   

17.
The concept of sensitization has a long history in psychology, and on both empirical and logical grounds it has been argued that sensitization and conditioning denote different neurophysiological processes. Investigators have devised elaborate control procedures that purport to differentiate sensitized and conditioned responses. But, mainly on logical grounds, it is argued that there is no valid basis for considering sensitization and conditioning as separate processes. A theory of learning is proposed in which sensitization is the basic construct.  相似文献   

18.
19.
20.
Light is the dominant environmental cue for entrainment of circadian rhythms. In mammals, light entrains rhythms by resetting the phase of a circadian pacemaker located in the hypothalamic suprachiasmatic nucleus (SCN). Until recently, the mechanism responsible for pacemaker resetting by light was thought to be exclusively sensitive to photic cues. New experiments indicate, however, that this mechanism is more plastic than once thought; is amenable to conditioned stimulus control; and is capable of acquiring, through conditioning, new response capabilities. These experiments showed that, in rats, a neutral stimulus paired with light in Pavlovian conditioning trials is capable of eliciting cellular and behavioral effects characteristic of circadian clock phase resetting by light, expression of Fos protein in the ventrolateral region of the SCN, and phase shifts of free-running rhythms. These novel results open up a previously unappreciated perspective on photic phase resetting and entrainment of circadian rhythms. Specifically, they suggest that the process normally initiated by light to reset the clock can be modified by learning and events in the environment that reliably precede the onset of light can assume the resetting function of light.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号