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151.
The COVID-19 pandemic is a global crisis emanating both from a virus (SARS-CoV-2) and from the drastic actions to contain it. Here, we reflect on the immediate responses of most world powers amid the pandemic chaos: totalitarian surveillance and nationalist isolation. Drawing on published literature, we consider measures such as wildlife-use bans, lockdowns and travel restrictions, along with their reverberations for people, economies and the planet. Our synthesis highlights significant shortfalls of applying command-and-control tactics in emergencies. For one, heavy-handed bans risk enormous unintended consequences and tend to fail if they lack legitimacy or clash with people’s values. Furthermore, reactive and myopic strategies typically view the pandemic as a stand-alone crisis, rather than unravelling the complex interplay of nature-society interactions through which zoonotic diseases originate. A return to adaptive management approaches that recognise root causes and foster socio-ecological resilience will be essential to improve human and planetary health and mitigate future pandemics.  相似文献   
152.
目的:对某油田采出水用杀菌剂毒性进行评价,为员工安全操作及职业病防护提供依据。方法:采用动物试验方法,对某油田采出水用杀菌剂进行急性毒性实验研究。结果:该油田采出水用杀菌剂对SD大鼠的急性经口半数致死剂量(LD 50)为3160 mg/(kg·bw),属实际无毒级;对普通级成年新西兰白兔皮肤为中等刺激性,对眼睛为严重眼损伤/对眼造成不可逆影响;对普通级白化豚鼠皮肤为低致敏性。结论:该油田采出水用杀菌剂对皮肤、眼睛可能存在较大损伤,作业人员进行相关作业时应做好防护。  相似文献   
153.
苯并[a]芘(BaP)是一类兼具强致癌性和非致癌毒性的物质,可随PM_(2.5)经呼吸途径进入人体而威胁健康.本文采集2016年北京城区监测点PM_(2.5)样品并采用气相色谱质谱联用仪测定其载带BaP浓度.通过BaP的流行病学及动物毒理学数据的检索和分析,确定BaP呼吸暴露的致癌和非致癌毒效应评价终点及其剂量效应关系.运用伤残调整生命年(DALYs)指标估算了呼吸途径人群PM_(2.5)载带BaP暴露导致的疾病负担.结果显示北京市BaP导致总疾病负担为431.36 DALYs·a~(-1),每千人DALYs为0.03 a~(-1).其中非致癌效应的疾病负担为1.98 DALYs·a~(-1),致癌效应为429.39 DALYs·a~(-1).不同毒效应的疾病负担排序为:癌症(99.54%)发育毒性(0.41%)生殖毒性(0.04%).不同季节的疾病负担贡献差异较大.北京市BaP暴露导致疾病负担的主要贡献季节为冬季,疾病负担贡献的顺序为冬季(88.01%)秋季(4.91%)春季(4.34%)夏季(2.74%).  相似文献   
154.
Phytophthora ramorum, cause of sudden oak death, is a quarantined, non-native, invasive forest pathogen resulting in substantial mortality in coastal live oak (Quercus agrifolia) and several other related tree species on the Pacific Coast of the United States. We estimate the discounted cost of oak treatment, removal, and replacement on developed land in California communities using simulations of P. ramorum spread and infection risk over the next decade (2010-2020). An estimated 734 thousand oak trees occur on developed land in communities in the analysis area. The simulations predict an expanding sudden oak death (SOD) infestation that will likely encompass most of northwestern California and warrant treatment, removal, and replacement of more than 10 thousand oak trees with discounted cost of $7.5 million. In addition, we estimate the discounted property losses to single family homes of $135 million. Expanding the land base to include developed land outside as well as inside communities doubles the estimates of the number of oak trees killed and the associated costs and losses. The predicted costs and property value losses are substantial, but many of the damages in urban areas (e.g. potential losses from increased fire and safety risks of the dead trees and the loss of ecosystem service values) are not included.  相似文献   
155.
肉桂是常用的中药和调味剂,药理作用广泛.临床应用情况与对机体多系统疾病的研究结果表明,肉桂在老年病方面具有防治作用,结合老年病的现状探讨其在老年病防治中的应用前景.  相似文献   
156.
Gastrointestinal parasitism is one of the diseases that has the highest economic impact on the Argentinian beef production system, rendering it inefficient. In the region of the Humid Pampas, it has been estimated that 22 million dollars are lost annually because of the death of calves and 170 million dollars are lost in sub-clinic costs. A mathematical model with fuzzy parameters was constructed for the analysis of the free-living stages of gastrointestinal parasites, with the purpose of estimating the pool of L3 larvae available for migration to pasture and the levels of infection in pasture at any time of the year under different climatic conditions. The model is formulated in terms of a system of three difference equations. These equations describe the abundance of parasites in each of the successive stages of the population development. The model was calibrated and tested with data gathered through fieldwork carried out in Tandil (37°19′S, 59°08′05″W), province of Buenos Aires (Argentina) and the corresponding weather data. A comparison between model simulations and fieldwork data obtained in other locations achieved satisfactory results.  相似文献   
157.
The aim of this study is to investigate changes in cardiovascular activity associated with a high mental workload. The reported experiments, carried out in naturalistic settings, point to information load and information processing under time pressure as main risk factors. This kind of occupational stress had to be dealt with by two of the three groups under investigation: brokers and simultaneous interpreters; it was not experienced by lecturing university professors. The pattern of cardiovascular activity of the two former groups consisted of overmobilization of cardiovascular activity at the beginning of work, and only partial normalization of task-evoked changes in cardiovascular activity at the end of work. Substantial elevations of diastolic blood pressure and tachycardia, which followed earlier overmobilization, resemble a miniature copy of changes seen in the development of cardiovascular diseases.  相似文献   
158.
阐述了张家界市森林病虫害的发生特点、森防工作面临的问题,并提出了强化森防工作的建议.  相似文献   
159.
160.
Charcot-Marie-Tooth disease type 1A (CMT1A) is a frequent hereditary motor and sensory neuropathy of the peripheral nerves. In most cases, the disease is associated with a 1.5 Mb tandem duplication at 17p11.2. A 42-year-old pregnant woman requested prenatal diagnosis because of her age and since both her husband and two children were severely affected with CMT1. The CMT1A duplication was demonstrated in the father's, the two children's, and the fetus's DNA using different molecular genetic methods. Although cytogenetical analysis showed a normal female karyotype in the fetus, the parents decided to terminate the pregnancy because of the genetic risk associated with the CMT1A duplication.  相似文献   
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