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Scientists are increasingly using Twitter as a tool for communicating science. Twitter can promote scholarly discussion, disseminate research rapidly, and extend and diversify the scope of audiences reached. However, scientists also caution that if Twitter does not accurately convey science due to the inherent brevity of this media, misinformation could cascade quickly through social media. Data on whether Twitter effectively communicates conservation science and the types of user groups receiving these tweets are lacking. To address these knowledge gaps, we examined live tweeting as a means of communicating conservation science at the 2013 International Congress for Conservation Biology (ICCB). We quantified and compared the user groups sending and reading live tweets. We also surveyed presenters to determine their intended audiences, which we compared with the actual audiences reached through live tweeting. We also asked presenters how effectively tweets conveyed their research findings. Twitter reached 14 more professional audience categories relative to those attending and live tweeting at ICCB. However, the groups often reached through live tweeting were not the presenters’ intended audiences. Policy makers and government and non‐governmental organizations were rarely reached (0%, 4%, and 6% of audience, respectively), despite the intent of the presenters. Plenary talks were tweeted about 6.9 times more than all other oral or poster presentations combined. Over half the presenters believed the tweets about their talks were effective. Ineffective tweets were perceived as vague or missing the presenters’ main message. We recommend that presenters who want their science to be communicated accurately and broadly through Twitter should provide Twitter‐friendly summaries that incorporate relevant hashtags and usernames. Our results suggest that Twitter can be used to effectively communicate speakers’ findings to diverse audiences beyond conference walls.  相似文献   
184.
The provision of sheltered housing for sale in Scotland has experienced rapid growth since the opening of the first scheme in 1982. Development has been geographically concentrated in a small number of inner city and rural (coastal) areas. The expectation of continued rapid expansion is unlikely if recent trends of slower growth continue. This paper uses evidence from interviews with developers and owners of sheltered and mainstream housing, to examine the possible future contribution of the private market. On the basis of such evidence it raises questions about the relevance of some existing planning policies.  相似文献   
185.
This study concerns design features of urban parking lots which can increase the perception of such areas as both safe and attractive. College students evaluated the attractiveness and perceived security associated with 180 scenes of parking lots adjacent to commercial and multi-family residential structures in Atlanta and Athens, Georgia, U.S.A. High intergroup correlations (r > 0·90) indicated the reliability of evaluations of both perceived features. Regressions of physical features on perceived security ratings and attractiveness ratings yielded highly predictive models (R2 = 0·76 and 0·80, respectively). For both sets of ratings a Maintenance and Design factor accounted for the most variance. Although attractiveness ratings were higher as the total amount of vegetation increased in a scene, security was in general rated higher only when vegetation was well maintained and appeared to be installed as part of a landscape design. Attractiveness was generally higher for multi-family residential scenes than for commercial scenes. Perceived security was higher for frontal views of structures, especially when entrances were proximate to the viewer. Research implications are discussed in terms of the impact of natural features in urban areas for increasing attractiveness and reducing fear of crime.  相似文献   
186.
甲胺磷农药废水生化处理高效菌选育的研究   总被引:23,自引:1,他引:23  
王倩如  叶晶菁 《化工环保》1995,15(4):205-210
从用甲胺磷农药废水长期驯化的活污泥中,筛选得到两株降解甲胺磷农药废水中有机磷的高效菌,经鉴定一株为蜡样芽孢杆菌(Bacilluscereus)。另一株为嗜中温假单胞菌(Pseudomonasmesophilica)。确定了上述高效菌的最适生长条件和降解有机磷的能力,混合高效菌的有机磷去除率达99.7%。  相似文献   
187.
In the present study we examined (1) community opinion of airport noise-abating alternatives and (2) the influence of perceived control on attitudes concerning noise-abatement policies and annoyance toward aircraft noise. We proposed that residents who perceive themselves as having little control over aircraft noise exposure would express higher levels of annoyance than residents who believe they have some degree of control. Furthermore, residents with low levels of perceived control would be less favorable toward proposed noise-abatement alternatives. Survey results collected from 239 households within the 65 CNEL contour of a community airport in Southern California support these hypotheses. Findings indicate strong public support for noise abatement and strong opposition to land-use alternatives. In addition, residents' perceptions of control in the airport planning and management process are significantly related to their annoyance with noise and their opinions about noise management policies.  相似文献   
188.
环保执法难点浅析   总被引:3,自引:0,他引:3  
环保执法是贯彻实施我国环境保护这一基本国策的重要保证。但是,在基层环保执法工作中常常遇到诸如被执法企业受地方保护主义的庇护、公众的环保意识薄弱、环保执法队伍自身素质差、执法水平低、执法力量薄弱、技术装备落后等问题。为维护环保法的尊严,严肃执法程序,确保环保执法顺利进行,分析研究这些问题的实质和存在的背景条件是必要的,并为解决这类问题作有益的探讨。  相似文献   
189.
通过对四川省科技人力资源的潜力、结构变化的分析,提出建立统一规范的科技人才培养经费投入政策,加强科技人才资源的再开发,不拘一格引进科技人才,建立四川省科技人力资源监测系统等对策。  相似文献   
190.
计划火烧是预防森林火灾的一种有效手段,成本低,效果显著。本文详细阐述了计划火烧的意义和作用、计划火烧前的准备工作,并提出了计划火烧的注意事项及实际操作要领。  相似文献   
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