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1.
《Ergonomics》2012,55(7):858-868
The beginning of a new century is an appropriate moment to consider the role of ergonomics in relation to the problems facing society. To help solve these serious global problems, ergonomics needs to be open to new disciplines, particularly those in the social sciences. Also, it may be difficult to generalize research on human-centred sociotechnical design without taking into account national characteristics, economics and political constraints. Currently there is more interest than ever in what ergonomics has to offer, but to deliver its promise requires a much broader approach than is usual. By adopting such new approaches one may help solve both the problems of the overdeveloped post-industrial societies and those of the societies of the Third World, where a new approach to work and economics may provide an improved chance for development given the recent changes in global economic policy.  相似文献   
2.
大亚湾核电站在近 1 0年的安全运行实践中建立并不断完善了以“全员培训、全体参与、全过程管理”为基本内容的辐射防护和最优化 (ALARA)管理体系 ,同时在“基础结构 (infrastructure)”上下功夫 ,努力构筑该体系有效运作的平台。本文综合介绍了大亚湾核电站辐射防护和最优化管理体系的内容和特点及其有效实施的基本经验。为了有效实施这一管理体系 ,核电站必须加强辐射防护责任制和辐射防护人员的主导作用 ,尤其是在高辐射风险作业中的技术支持和监督作用 ;必须强调该体系与核电站安全运行管理体系的有机结合和积极互动 ;必须重视安全文化建设 ,坚持经验反馈和透明度 ,保证该体系在实践中持续改进  相似文献   
3.
文章从树立正确的道德规范、建立良好的行业信誉、树立客户至上的观念、创造公平有序的竞争环境等四个方面提出了培育白蚁防治行业道德文化的对策。  相似文献   
4.
A comparison of different isolation techniques and culture media for detection of filamentous fungi and yeasts in the aquatic environment revealed that the use of membrane filtration with the media dichloran rose bengal chloramphenicol (DRBC) optimized fungi detection in terms of abundance and variety in three untreated water sources with very different characteristics (surface water, spring water, and groundwater). The diversity of the fungi population captured by direct DNA extraction of fungi collected by membrane filtration was compared with the isolates obtained after selective growth using different culture media through amplification of the internal transcribed spacer gene and denaturing gradient gel electrophoresis (DGGE). The Czapek-Dox agar, Sabouraud dextrose agar, and DRBC media showed closer similarities to those obtained by the uncultured biomass for the different water sources. Based on these data and the best enumeration results, DRBC is recommended for the assessment of fungi in water sources using culture-based methods. DGGE was also used to monitor temporal variations in the fungal population structure and showed that each water matrix possessed a distinct population profile as well as that changes in the fungal community can be expected in the different matrices throughout the year.  相似文献   
5.
The diversity and dynamics of the dominant bacterial communities arising during the pickling process of bamboo shoots (Dendrocalamus latiflorus) were investigated by nested polymerase chain reaction denaturing gradient gel electrophoresis combined with quantitative real‐time polymerase chain reaction. Results showed only several kinds of halophilic bacteria during early sampling time (0?3 days). After pickling for 7 days, Lactococcus lactis significantly increased (< 0.05, quantities were 6.39 × 105 copies μL?1) and became the first dominant bacterium. After pickling for 14 days, Weissella sp. bands appeared and quickly became dominant on the 21st day (4.07 × 106 copies μL?1). As maturation progressed, Lc. lactis decreased in intensity whereas Weissella sp. increased in intensity. Finally, the quantities of Weissella sp. (2.50 × 107 copies μL?1) became higher than those of Lc. lactis (1.43 × 107 copies μL?1) after pickling for 56 days. The pickling process was initiated by Lc. lactis, followed by Lc. lactis and Weissella sp., and was finally succeeded by Weissella sp.  相似文献   
6.
本文主要探讨近代上海地域文化特征及其建筑立面的装饰,归纳了近代上海四种不同的建筑类型,在其建筑立面的装饰上,反映出的地域文化特征。  相似文献   
7.
徽派建筑是徽文化的重要组成部分,是重要的人类文化遗产。其中,徽州古民居是徽派建筑中数量最多的一个门类,作为徽派建筑的典型代表,与人们的关系最为密切,在历史上有过相当长的一段辉煌时期。通过对徽派建筑文化的追溯,来了解徽州古民居动态形成的特点及原因。  相似文献   
8.
The study compared the growth capability of probiotic (Lactobacillus acidophilus La05, Lactobacillus casei Lc01 and Bifidobacterium animalis Bb12) and non-probiotic (Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus) cultures on twenty-one culture media grouped according to selectivity: non-selective agars, selective agars without antibiotics and MRS agars containing different combinations of lithium chloride, cystein, bile salts and antibiotics. Four of these media were selected for quantitative enumeration of L. acidophilus La05, L. casei Lc01, and B. animalis Bb12. The best culture media and incubation conditions for enumeration of the probiotic cultures were: B. animalis: MRS agar with dicloxacillin, 37 °C or 42 °C, anaerobiosis; L. acidophilus: MRS agar with bile salts, 37 °C or 42 °C, aerobiosis; L. casei: MRS agar with lithium chloride and sodium propionate, 37 °C or 42 °C, aerobiosis or anaerobiosis. Plating on MRS with glucose replaced by maltose, 37 °C or 42 °C, anaerobiosis, will distinguish probiotic from non-probiotic cultures. For enumeration of each probiotic in a mixed culture, the following media and incubation conditions were recommended: B. animalis: 4ABC-MRS, 42 °C, anaerobiosis, L. acidophilus: LC medium, 42 °C, aerobiosis or anaerobiosis and L. casei: LP-MRS, 42 °C, aerobiosis or anaerobiosis. In all experiments, differences in counts using pour plating or surface plating were not significant (P ≤ 0.05).  相似文献   
9.
Listeria monocytogenes poses a serious threat to public health, and the majority of cases of human listeriosis are associated with contaminated food. Reliable microbiological testing is needed for effective pathogen control by food industry and competent authorities. The aims of this work were to estimate the prevalence and concentration of L. monocytogenes in minced pork meat by the application of a Bayesian modeling approach, and also to determine the performance of three culture media commonly used for detecting L. monocytogenes in foods from a deterministic and stochastic perspective. Samples (n = 100) collected from local markets were tested for L. monocytogenes using in parallel the PALCAM, ALOA and RAPID'L.mono selective media according to ISO 11290-1:1996 and 11290-2:1998 methods. Presence of the pathogen was confirmed by conducting biochemical and molecular tests. Independent experiments (n = 10) for model validation purposes were performed. Performance attributes were calculated from the presence–absence microbiological test results by combining the results obtained from the culture media and confirmative tests. Dirichlet distribution, the multivariate expression of a Beta distribution, was used to analyze the performance data from a stochastic perspective. No L. monocytogenes was enumerated by direct-plating (<10 CFU/g), though the pathogen was detected in 22% of the samples. L. monocytogenes concentration was estimated at 14–17 CFU/kg. Validation showed good agreement between observed and predicted prevalence (error = −2.17%). The results showed that all media were best at ruling in L. monocytogenes presence than ruling it out. Sensitivity and specificity varied depending on the culture-dependent method. None of the culture media was perfect in detecting L. monocytogenes in minced pork meat alone. The use of at least two culture media in parallel enhanced the efficiency of L. monocytogenes detection. Bayesian modeling may reduce the time needed to draw conclusions regarding L. monocytogenes presence and the uncertainty of the results obtained. Furthermore, the problem of observing zero counts may be overcome by applying Bayesian analysis, making the determination of a test performance feasible.  相似文献   
10.
研究了隐甲藻(Crypthecodinium cohnii ATCC 30772)以摇瓶发酵培养方式获得最大生物产量和最高二十二碳六烯酸(docosahexaenoic acid,DHA)产量的培养条件.结果表明,有利于隐甲藻生长和DHA积累的最佳培养条件为:培养温度为22℃,先以12g/L葡萄糖为碳源培养4d,后再以3g/L醋酸钠为碳源培养4d.由此获得的生物产量为234.85mg/(L·d),DHA产量为17.45mg/(L.d),DHA含量为74.36mg/g菌体.  相似文献   
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