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41.
Marincioni F 《Disasters》2007,31(4):459-476
A comparative survey of a diverse sample of 96 US and Italian emergency management agencies shows that the diffusion of new information technologies (IT) has transformed disaster communications. Although these technologies permit access to and the dissemination of massive amounts of disaster information with unprecedented speed and efficiency, barriers rooted in the various professional cultures still hinder the sharing of disaster knowledge. To be effective the available IT must be attuned to the unique settings and professional cultures of the local emergency management communities. Findings show that available technology, context, professional culture and interaction are key factors that affect the knowledge transfer process. Cultural filters appear to influence emergency managers' perceptions of their own professional roles, their vision of the applicability of technology to social issues, and their perspective on the transferability of disaster knowledge. Four cultural approaches to the application of IT to disaster communications are defined: technocentric; geographic,; anthropocentric; and ecocentric.  相似文献   
42.
To investigate the effects of humic acids (HAs) on the ability of plants to defend themselves against oxidative stress, barley was hydroponically cultured in the absence and presence of HAs, and the antioxidant enzymatic activities (catalase, superoxide dismutase, ascorbate and glutathione peroxidases) of root tissue were evaluated. Auxin-like structures in HAs, which were extracted from an oxidation product of lignite (LHA) and compost derived from cattle manure (CHA), were identified by pyrolysis-gas chromatography/mass spectrometry (GC/MS) with tetramethylammonium hydroxide. The LHA, which had the lower molecular weight, was more effective in promoting the growth of barley root than CHA. However, the amounts of auxin-like structures in the CHA were much higher than those for LHA. The antioxidant enzymatic activities were initially decreased in the presence of LHA and CHA at the first day after refreshing the culture solution, but were significantly increased on the second day. The CHA sample, which contained relatively high levels of phenolic acids that contained auxin-like structures, was effective in increasing four types of enzymatic activities, while the activities of catalase and ascorbate peroxidase were increased in the presence of LHA, which contains naphthalene derivatives. These results indicate that using HAs as a supplement can be effective in enhancing antioxidation enzymatic activities, while the appearance of the effects is retarded because of the decomposition and release of auxin-like compounds from HAs by organic acids from the plant roots.  相似文献   
43.
采用微生物筛选、纯化技术,获得了降解对苯二甲酸(TA)的YPC—TA1,YPC—TA2,YPC-TA3,YPC—TA44株菌株。将筛选出的TA降解菌固定化,处理初始TA质量浓度为2650mg/L的模拟废水,降解36h后TA去除率达100%。用TA降解芮在生物流化床反应器中处理PTA废水,最佳容积负荷为6.7kg/(m^3·d)。生物流化床反应器可在容积负荷为6.0~6.5kg/(m^3·d)的较佳条件下长周期稳定运行,COD去除率保持在91%左右,TA去除率保持在94%左右。低pH废水冲击和高容积负荷废水冲击时COD,TA去除率均明显下降,恢复正常讲水后3~4d,COD,TA去除率均恢复正常。  相似文献   
44.
玉米浸泡液制备苏云金杆菌生物杀虫剂的影响因素研究   总被引:2,自引:0,他引:2  
以玉米淀粉生产过程中的浸泡液为培养基,摇瓶发酵培养苏云金杆菌生物杀虫剂,通过一系列单因子试验,考察了不同培养条件(种子液的种龄、接种量、浸泡液的含固率、初始pH值、摇床转速、发酵温度及发酵时间)对苏云金杆菌在玉米浸泡液中的生长(菌数增长与芽孢形成)以及发酵液的生物毒效的影响.研究表明,在最佳摇瓶培养条件(种子液种龄10 h,接种量2%,浸泡液含固量3%,初始pH值7.0~7.5,摇床转速200 r/min,发酵温度30℃)下发酵48 h,活菌数和活芽孢数分别可达到7.9×108 CFU/mL和5.5×108 CFU/mL,毒力效价为698.0 IU/μL.本试验可为生物农药的工业化生产提供实用参数.  相似文献   
45.
Introduction: Heterogeneous driving populations with many different origins are likely to have various sub-cultures that comprise of drivers with shared driver characteristics, most likely with dissimilar traffic safety cultures. An innovative methodology in traffic safety research is introduced which is beneficial for large datasets with multiple variables, making it useful for the multi-variate classification of drivers, driving attitudes and/or (risky) driving behaviours. Method: With the application of multidimensional scaling analysis (MDS), this study explores traffic safety culture in the State of Qatar using a questionnaire and investigates the similarity patterns between the questionnaire items, aiming to classify attitudes towards risky driving behaviours into themes. MDS is subsequently applied to classify drivers within a heterogeneous driving sample into sub-cultures with shared driver characteristics and different risky driving attitudes. Results: Results show that acceptance of speeding is highest among the young Arabic students and acceptance of distraction and drivers’ negligence such as phone use and not wearing a seatbelt is highest among male Arab drivers. Acceptance of extreme risk-taking like intoxicated driving and red-light running is highest among South-Asian business drivers. Conclusion: It is important and practical to understand risky behavioural habits among sub-cultures and thereby focussing on groups of drivers instead of individuals, because groups are easier to approach and drivers within sub-cultures are found to influence each other. By indicating which groups of drivers are most likely to perform specific risky driving themes, it is possible to target these groups and effectively emphasise certain subsets of risky driving behaviours during training or traffic safety education. Practical Applications: This study provides guidance for the improvement of driver education and targeted traffic safety awareness campaigns, intending to make changes to attitudes and habits within specific driver sub-cultures with the aim to improve traffic safety on the longer term.  相似文献   
46.
Popular music is a generation-specific zeitgeist, while music affords otherwise unobtainable engagement with environmental themes. Despite being the most widespread form of music there is a paucity of scholarship on climate change vis-à-vis popular music. In turn, this article explores how popular music may provide a soundtrack that narrates the rapidity of contemporary biophysical change. Approaches of conveying versus communicating climate change in music are considered across a spectrum of musical forms, from contemporary and historical popular music to contemporary classical music and sound art. The article applies the framework of shifting baselines to music engaged with environmental change in order to formulate a closer relationship between objective and quantitative intergenerational biophysical change and subjective and qualitative socio-cultural change. To cease losing track of such inexorable degradation, the article speculates on future musical forms that may obviate such intergenerational myopia by conveying and/or communicating the unprecedented rapidity of biophysical change.  相似文献   
47.
分别采用琼脂平板、琼脂糖平板、水洗洋菜平板和硅胶平板分离培养城市污水处理厂好氧活性污泥中的硝化细菌。在相同的培养条件下,琼脂平板和水洗洋菜平板有杂菌生长;硅胶平板制作过程繁琐,培养后期出现失水性干裂;琼脂糖平板没有杂菌生长。通过对分离菌株的表观形态观察和NorB基因检测鉴定分离菌株,证明琼脂糖分离出了目的菌株,适合生长周期长的自养硝化细菌分离培养。  相似文献   
48.
利用可持续发展指数(SDI)对湖北“两圈”各市州发展现状进行了评价,而后利用9年的人均生物资源生态承载量年平均增长率、人口年平均增长率和足迹承载量比值年平均增长率及2006年相关数据对未来44年进行了预测。结果表明,截至2006年底,湖北省有一半以上国土面积的生物资源开采超过当地土地负荷,人均生物资源生态承载量持续下降,资源日益紧张,呈不可持续发展;武汉城市圈2006年生物资源生态足迹超出生物资源生态承载量的32%;鄂西生态文化旅游圈(简称:鄂西生态圈)除襄樊、荆州、荆门因人口多,生物资源生态足迹较大等原因导致SDI值较高外,其他市州的SDI值均较低;神农架的SDI最小;武汉城市圈人均生物资源生态承载量呈负增长,人口控制较好,足迹承载量比值增长较快;鄂西生态圈人均生物资源生态承载量呈负增长,增长速率大于武汉城市圈和湖北省,人口控制较差,足迹承载量比值增长较慢;按照现有发展模式,无论是武汉城市圈还是鄂西生态圈,无论其当前发展是可持续性还是不可持续的,未来他们都将进入不可持续的发展状态。因此,对“两圈”进行规划时要根据各自发展现状制定长期、科学的发展规划.  相似文献   
49.
江苏阳澄湖螺类群落的空间分布格局   总被引:3,自引:0,他引:3  
2008年1月~2009年10月对江苏阳澄湖螺类群落结构进行了季节调查研究。共采集到螺类4科5属6种,优势种为铜锈环棱螺,次优种为长角涵螺。阳澄湖螺类平均密度为220±47 ind./m2,平均生物量为2331±469 g/m2,螺类密度和生物量在年际和季节间均无明显差异,但群落结构存在显著的空间变化,密度在东湖区和中华绒螯蟹围网养殖区较大、西湖区最小,生物量围网养殖区最高、西湖区最低;铜锈环棱螺密度围网养殖区最高、西湖区最低,长角涵螺密度东湖区最高、围网养殖区次之、入湖河流及其它湖区极低。中华绒螯蟹养殖未导致围网养殖区螺类数量下降,螺类(主要是铜锈环棱螺)的投放可能是该区螺类密度、生物量及铜锈环棱螺所占比例较高的主要原因之一。逐步回归分析表明,水深是影响螺类群落整体密度和生物量空间分布差异的主要因子;典型对应分析(CCA)表明,铜锈环棱螺主要分布在叶绿素a较高的水域,而长角涵螺和纹沼螺则主要分布在透明度较大的地方  相似文献   
50.
培养藻类制取生物能源的研究   总被引:2,自引:0,他引:2  
能源紧张和环境污染是全世界所面临的共同问题,用藻类替代传统作物生产生物能源是生物质能的重要发展方向之一。文章介绍了国内外对藻类培养条件、光生物反应器型式、藻类基因工程、藻细胞收集方法以及能源藻类生产系统的研究成果。研究认为,以藻类为原料生产生物燃料具有良好的发展前景,并指出了今后能源藻类生长的重点研究方向。  相似文献   
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