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41.
随着医学实验动物学科的发展及实验动物生产、使用许可证管理办法的实施,本文介绍了我校屏障系统动物实验设施的运营管理模式,包括建立完整的文件及系统内标准操作的管理体系、人员队伍的建设和管理、实验动物环境设施的管理、系统内环境物品的管理等,总结相关经验以供同行参考。  相似文献   
42.
Platform technologies (PT) are techniques or tools that enable a range of scientific investigations and are critical to today''s advanced technology research environment. Once installed, they require specialized staff for their operations, who in turn, provide expertise to researchers in designing appropriate experiments. Through this pipeline, research outputs are raised to the benefit of the researcher and the host institution.1 Platform facilities provide access to instrumentation and expertise for a wide range of users beyond the host institution, including other academic and industry users. To maximize the return on these substantial public investments, this wider access needs to be supported. The question of support and the mechanisms through which this occurs need to be established based on a greater understanding of how PT facilities operate. This investigation was aimed at understanding if and how platform facilities across the Bio21 Cluster meet operating costs. Our investigation found: 74% of platforms surveyed do not recover 100% of direct operating costs and are heavily subsidized by their home institution, which has a vested interest in maintaining the technology platform; platform managers play a major role in establishing the costs and pricing of the facility, normally in a collaborative process with a management committee or institutional accountant; and most facilities have a three-tier pricing structure recognizing internal academic, external academic, and commercial clients.  相似文献   
43.
The intensification in livestock production has increased the need of efficient treatments of waste streams especially to preserve as much as possible, the nutrients into the soil-plant system. Composting is a cheap, efficient and sustainable treatment for solid wastes that is always included in any manure treatment scenario. In this paper, an overview about the environmental and safety challenges of composting of manures is made considering the compost quality requirements established by the main demanding sectors. Co-composting and additive strategies are presented as feasible options for the improvement of compost quality. For quality evaluation of manure compost, the use of both classical and innovative instrumental techniques could increase our knowledge about added properties in compost, especially those related to organic matter stability.  相似文献   
44.
Antarctic fishes and invertebrates, including Antarctic krill, are generally stenothermal, and it is necessary to maintain water temperature about 0°C to keep them in good condition. Because the effects of nitrifying bacteria are limited by the extremely low temperature of about 0°C, biological filtration does not keep up with the deterioration of water quality resulting from the excrement of animals and un-eaten food. It is therefore necessary to exchange seawater frequently in our present cold-water aquarium.

We developed a new system at Port of Nagoya Public Aquarium (PNPA) that keeps Antarctic marine animals in good condition. The improved system increases the temperature of sea water to 10°C prior to biological filtration and thereby increases the effectiveness of the biological filter. The krill-rearing container was constructed inside the main tank so that the water flow inside the rearing container could be stopped. This avoids a rapid reduction of phytoplankton feed due to turnover of the seawater in the system while krill were fed. As a result of these improvements, long-term rearing, mass culture and reproduction of Antarctic krill are possible. We have exhibited Antarctic marine animals since the opening of PNPA in 1992, and we have exhibited Antarctic krill continuously since 1997. In this article, we detail the Antarctic krill breeding facilities at PNPA.  相似文献   
45.
Detailed knowledge of the architecture and molecular structure of biofilms during composting is important for understanding the underlying mechanisms of rapid composting with inoculation. In this study, multiple fluorescent labeling and two-dimensional Fourier transform infrared (FTIR) correlation spectroscopy were used to characterize biofilms during composting with and without inoculation with a cellulose-degrading strain, Aspergillus fumigatus F12. The results showed that inoculation with A. fumigatus F12 allowed the compost to rapidly reach the thermophilic phase. Further investigation demonstrated that the role of A. fumigatus F12 during composting was to destroy the network-like structure of cellulose and to increase the contact of other biopolymers with microorganisms, as observed in situ using multiple fluorescence labeling combined with confocal laser scanning microscopy (CLSM). Two-dimensional FTIR correlation spectroscopy supported the conclusion that the critical role of inoculation in composting was attributed to the degradation of cellulose (1420 cm?1) prior to other biopolymers. In summary, multiple fluorescent labeling and two-dimensional FTIR correlation spectroscopy can be used as a novel tool for characterizing biofilms and the critical roles of microorganisms in composting.  相似文献   
46.
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   
47.
Xiao JF  Wu JG  Shi CH 《遗传》2011,33(12):1409-1413
先进的实验教学设施及开放水平是提升遗传学实验教学质量的重要保证。文章介绍了数码显微互动教学系统、细胞流线仪、近红外测定仪等一些先进仪器设备在遗传学实验教学中发挥的积极作用,列举了开放实验对培养学生创新意识和创新能力的重要意义,并提出了进一步做好遗传学教学实验室建设的一些设想。  相似文献   
48.
A mathematical model which integrates empirically derived microbial growth kinetics with heat and mass transfer phenomena and substrate degradation kinetics has been developed to capture the dynamics of the aerobic composting of a switchgrass and dog food mixture over a period of 64 h. The model incorporated three microbial populations of yeasts, bacteria and fungi that metabolized composting material consisting of sugars and starches, cellulose and hemicelluloses to produce heat and utilize oxygen in a static, cylindrical reactor employing forced aeration. Model predictions captured well the dynamics obtained experimentally between physical and microbial variables and the model has the potential to become a predictive tool for substrate degradation during aerobic composting processes.  相似文献   
49.
Wang K  Li W  Guo J  Zou J  Li Y  Zhang L 《Bioresource technology》2011,102(9):5528-5532
Spatial differences and temporal changes in biological activity characteristics were investigated in a static reactor using intermittent aeration during the sewage sludge composting process. Pumice was proposed as a bulking agent in the composting of sewage sludge. Variations in temperature, moisture, oxygen level, volatile solids, specific oxygen uptake rate (SOUR) and dehydrogenase activity (DHA) were determined during 28 days of composting. The peak temperature in the upper region of the reactor was 10 °C higher than that at the bottom. The moisture level in the middle region was significantly higher than that of other positions. Analysis of SOUR and DHA indicated that the lowest level of sludge stability was at the bottom region. These spatial and temporal differences in biochemical dynamics in the static system could extend the composting period and affect product uniformity.  相似文献   
50.
The evolution of sporulating bacteria in full-scale composting facilities with online temperature monitoring has been poorly studied, although organic matter recycling increases. We analysed Clostridium perfringens and sulphite-reducing clostridia (SRC) by cultivation, and streptomycetes by real-time PCR in five full-scale, temperature-monitored and aerated composting processes, and two pilot-scale drum composters. Facilities composted woodchips, sawdust, peat, or bark amended sludge or source-separated biowaste. Streptomycetes genes of 0.21-110 × 107 copies/g feed increased fast to 0.019-33 × 109 copies/g, and then were equal or decreased. SRC of 0.06-2.2 × 107 cfu/g feed decreased to 0-600 cfu/g, with re-growth in two facilities. End products were clean of C. perfringens, detected in sludge composts. Although processes contained large quantities of spore-forming bacteria, in the best facilities end products had the high quality. Temperature (>55 °C, >2d) was not related to the end compost quality, but relations between waste and bulking agent qualities, aeration, and processing time should be better controlled.  相似文献   
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