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231.
湖北省碘缺乏病流行特征及防治对策   总被引:1,自引:1,他引:0  
丁宗洲  安从俊 《灾害学》1996,11(4):39-42
湖北省碘缺乏病的流行分布与地势、地貌,土壤,地层岩性,饮水中的碘含量以及构造带密切相关,给病区居民供应碘盐和改善生态环境缺碘状况,是防治碘缺乏病的根本措施。  相似文献   
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采用广义相加模型评估臭氧和细颗粒物(PM2.5)暴露对2008~2017年上海浦东居民慢性阻塞性肺疾病(COPD)死亡的超额危险度(ER)和寿命损失年(YLL)的影响.结果表明:臭氧污染集中在4~6月,PM2.5污染集中在12月、1~2月,10a间臭氧浓度逐年增加,PM2.5有小幅下降;在最大滞后效应下,臭氧每增加10μg/m3,ER和YLL分别为1.34%(95% CI:0.57%~2.12%)和54.98(95% CI:16.36~106.41)人·a;PM2.5每增加10μg/m3,两者分别为2.66%(95% CI:1.54%~3.79%)和130.92(95% CI:42.47~274.28)人·a;臭氧对男性和<85岁人群影响显著,PM2.5对女性和385岁人群影响显著;暖季时臭氧暴露相关的COPD死亡风险更高,冷季时PM2.5暴露相关的COPD死亡风险更高.臭氧和PM2.5致COPD死亡的影响可能因气温水平而异.  相似文献   
234.
为弄清颗粒污染物在慢性阻塞性肺病工人呼吸道内运动和沉积规律,采用数值方法讨论了2类阻塞性呼吸道内气固流动特性,分析了阻塞率(α)、阻塞位置、劳动强度等因数对流场分布、颗粒沉积形式和沉积率的影响.结果表明,α越大,病人局部缺氧越严重,当α=0.8时,相对缺氧率可达90%以上;劳动强度越强或受阻塞位置越深,病人发生哮喘的可能性愈高.呼吸道变形不会改变颗粒的沉积机制,但对其沉积形式有显著影响.α增大,劳动强度增强,粒径变大,均会导致颗粒沉积分布不对称性提高,且下呼吸道粒子沉积分布对称性更好.此外,呼吸道变形使总沉降率(ηt)减小,且α越大,ηt越小.发现对于低劳动强度,下呼吸道或者dp>5μm的大颗粒,αηt影响要更为显著.  相似文献   
235.
根据ISO 5349:2001规定,将三轴加速度传感器安装在割草机和绿篱机的手柄上,通过振动分析仪AWA 6258测量割草机和绿篱机的频率计权振动总值,以进行手传振动的危害评估。结果表明:割草机和绿篱机的日振动暴露量A(8)值均超过了我国标准规定的日暴露振动限值3.5 m/s2,预计分别经过1.8~8.5 a和1.9~5.2 a后,暴露于割草和修枝工种人群的10%以上将出现振动性白指,为了有效降低或避免手臂振动病的发生,该行业的作业人员每日接触振动的时间应该控制在2.6 h以内。  相似文献   
236.
Much progress has been made toward assessing and improving animal welfare in conservation. However, several glaring knowledge gaps remain where animal-welfare concerns exist but animal-welfare studies have not been performed in politically sensitive contexts. Based on contemporary issues in Australia, we identified 4 topics that require more research: animal-welfare oversight for operations designated as management (as opposed to research); animal-welfare impacts of biological agents used to control invasive animals; welfare of animals hunted recreationally; and animal-welfare impacts associated with indigenous wildlife use. Animal-welfare science may be applied to these sensitive topics through simple quantitative studies (e.g., quantifying the frequency of adverse animal-welfare events). Several such studies have effectively addressed animal-welfare concerns in similarly contentious contexts, including feral camel (Camelus dromedarius) culling in Australia, recreational hunting in Scandinavia, and indigenous whale hunting in the United States. For discussions of animal welfare in conservation to be evidence-based, courageous research is required in the 4 key areas we identified.  相似文献   
237.
Translocations are an important tool for wildlife conservation, although progress in the field of reintroduction biology has been hindered by the ad hoc and opportunistic nature of many translocations. We used an experimental translocation to elucidate the role of raccoon roundworm (Baylisascaris procyonis) and inbreeding depression in the decline of the Allegheny woodrat (Neotoma magister), an endangered species. We translocated woodrats from genetically diverse populations in the core of the species range to 4 previously occupied sites (reintroductions) and 2 sites supporting genetically depauperate populations (reinforcements) in Indiana (U.S.A.). In 2 reintroduction sites and 1 reinforcement site, we distributed anthelmintic baits to passively deworm raccoons and reduce the risk of woodrat exposure to roundworms. The remaining sites served as controls. We used raccoon latrine surveys and fecal flotation to monitor temporal variability in roundworm prevalence and effect of treatment. We used live trapping and microsatellite genotyping to monitor the demographic and genetic response of translocated populations over the following 54 months. At the conclusion of the study, 4 of 6 translocations were successfully maintaining abundance through local recruitment. The distribution of anthelmintic baits reduced levels of roundworm contamination, but levels of contamination were also low in 2 of 3 control sites. Reintroductions failed at control sites, one of which was due to high roundworm exposure. The other failed control reintroduction was likely attributable to demographic stochasticity and limited reproductive potential following initial mortality within the first 4 months. In both control and treatment reinforcements, increases in both allelic richness and heterozygosity were accompanied by increases in abundance, which is suggestive of genetic rescue. Our results demonstrate that mitigation of roundworm exposure through the distribution of anthelmintic baits can facilitate woodrat recovery and that diversity within genetically depauperate populations can be restored through the introduction of a limited number of individuals. El Uso de Reubicaciones Experimentales de Neotoma magister para Descifrar Agentes Causales de Disminución  相似文献   
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Abstract:  Barriers are used to achieve diverse objectives in conservation and biosecurity. In conservation management, fences are often erected to exclude introduced predators and to contain diseased animals or invasive species. Planning an efficient conservation fence involves a number of decisions, including the size and design of the enclosure. We formulated the first general framework for building a fence that minimizes long-term management costs by balancing the expense of constructing a more secure barrier against the costs of coping with more frequent failures. The approach systematically considers the range of potential solutions to a well-defined fencing problem and results in a solution that maximizes conservation return on investment. We illustrated this method by designing efficient fences to address two different conservation goals: exclusion of invasive predators from populations of threatened eastern barred bandicoots ( Perameles gunnii ) and maintenance of isolated populations of healthy Tasmanian devils ( Sarcophilus harrisii ). A systematic approach to conservation fencing allows the best fence design to be chosen quantitatively and defensibly. It also facilitates conservation decisions at a strategic level by allowing fencing to be compared transparently with alternative conservation management actions.  相似文献   
240.
This paper examines the current health policy response to the management of vector-borne disease (VBD), specifically Ross River (RR) virus, in subtropical coastal Australia. It demonstrates the multi-dimensional nature of the VBD problem and considers the value of more sustainable policy responses. The paper provides an integrated exploration of the incidence of RR virus in the context of socio-biophysical interactions and change, climate variability, and possible enhanced threat due to climate change. The study focuses on two subtropical coastal case study regions in Australia. Collectively, the existing and emerging socio-biophysical interactions in these regionsraise questions as to the future risks and management of RR virus, while climate change adds a significant further dimension. The paper demonstrates the need for the incorporation of environmental planning elements, particularly attention to strategic assessment and planning, into the traditional suite of health policy responses given the multi-dimensional nature of the problem and evident socio-biophysical environmental change.  相似文献   
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