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101.
为了解决目前国内现有工亡率数据所存在的局限性问题,引入我国工伤保险数据,并在此基础上分析2006—2016年我国及各地区的工亡率变化趋势, 进而运用泰尔指数分析法测算全国及各地区的工亡率地区差异。研究结果表明:2006—2016年,我国总体工亡率呈下降趋势,但整体水平仍偏高;西部明显高于东、中部,但东、中、西部之间的工亡率差异在缩小;东部、中部和西部内部各省市之间的差异还比较大。最后,提出设定管控工亡率指标时要注重追求本质上的进步,各地应采取措施解决不平衡的问题,完善标准化工亡报告制度,选择更高水平的国际对标体系。  相似文献   
102.
The conservation of wildlife requires management based on quantitative evidence, and especially for large carnivores, unraveling cause‐specific mortalities and understanding their impact on population dynamics is crucial. Acquiring this knowledge is challenging because it is difficult to obtain robust long‐term data sets on endangered populations and, usually, data are collected through diverse sampling strategies. Integrated population models (IPMs) offer a way to integrate data generated through different processes. However, IPMs are female‐based models that cannot account for mate availability, and this feature limits their applicability to monogamous species only. We extended classical IPMs to a two‐sex framework that allows investigation of population dynamics and quantification of cause‐specific mortality rates in nonmonogamous species. We illustrated our approach by simultaneously modeling different types of data from a reintroduced, unhunted brown bear (Ursus arctos) population living in an area with a dense human population. In a population mainly driven by adult survival, we estimated that on average 11% of cubs and 61% of adults died from human‐related causes. Although the population is currently not at risk, adult survival and thus population dynamics are driven by anthropogenic mortality. Given the recent increase of human‐bear conflicts in the area, removal of individuals for management purposes and through poaching may increase, reversing the positive population growth rate. Our approach can be generalized to other species affected by cause‐specific mortality and will be useful to inform conservation decisions for other nonmonogamous species, such as most large carnivores, for which data are scarce and diverse and thus data integration is highly desirable.  相似文献   
103.
Moose-vehicle collisions are a frequent traffic-safety issue, particularly in northern regions where moose are attracted to the near-road areas because they can consume sodium from de-icing salts that accumulate in pools at snowmelt. Moose that find salt pools near roads tend to remember their location and to re-visit them to get the sodium they need in their diet. This study investigated the trade-off between road avoidance and salt pool spatial memory in the movement behaviour of moose using an agent-based model to determine how the interplay of these two factors influences the frequency of road crossings in the Laurentides Wildlife Reserve (Québec, Canada). Mitigation measures studied were the removal of roadside salt pools and the construction of compensatory salt pools away from the road shoulder. A GPS telemetry program of moose in the study area was used to validate our model. The model moose with both road avoidance and salt pool spatial memory activated produced the best results when comparing to the real moose data. Results show that both road avoidance and salt pool spatial memory significantly affect moose road crossings, but that road avoidance explains most of the variance. Road avoidance tended to decrease the number of moose crossings, but this decrease was partly compensated by the spatial memory of salt pools which typically increased the likelihood that moose will cross the road. The trade-off between road avoidance and salt pool memory was largest when original salt pools were maintained. In simulations where road avoidance and salt pool memory were both turned off, the impact of mitigation measures on the number of road crossings was lowest. For the most realistic moose behavior, the management scenarios resulted in reductions in road crossings between 22% and 79%, and the best scenario is to completely remove roadside salt pools. If compensation salt pools are used, they should be located as far as possible from the roads (beyond 500 m) to have an impact on moose road crossings.  相似文献   
104.
Objective: Survival risk ratios (SRRs) and their probabilistic counterpart, mortality risk ratios (MRRs), have been shown to be at odds with Abbreviated Injury Scale (AIS) severity scores for particular injuries in adults. SRRs have been validated for pediatrics but have not been studied within the context of pediatric age stratifications. We hypothesized that children with similar motor vehicle crash (MVC) injuries may have different mortality risks (MR) based upon developmental stage and that these MRs may not correlate with AIS severity.

Methods: The NASS-CDS 2000–2011 was used to define the top 95% most common AIS 2+ injuries among MVC occupants in 4 age groups: 0–4, 5–9, 10–14, and 15–18 years. Next, the National Trauma Databank 2002–2011 was used to calculate the MR (proportion of those dying with an injury to those sustaining the injury) and the co-injury-adjusted MR (MRMAIS) for each injury within 6 age groups: 0–4, 5–9, 10–14, 15–18, 0–18, and 19+ years. MR differences were evaluated between age groups aggregately, between age groups based upon anatomic injury patterns and between age groups on an individual injury level using nonparametric Wilcoxon tests and chi-square or Fisher's exact tests as appropriate. Correlation between AIS and MR within each age group was also evaluated.

Results: MR and MRMAIS distributions of the most common AIS 2+ injuries were right skewed. Aggregate MR of these most common injuries varied between the age groups, with 5- to 9-year-old and 10- to 14-year-old children having the lowest MRs and 0- to 4-year-old and 15- to 18-year-old children and adults having the highest MRs (all P <.05). Head and thoracic injuries imparted the greatest mortality risk in all age groups with median MRMAIS ranging from 0 to 6% and 0 to 4.5%, respectively. Injuries to particular body regions also varied with respect to MR based upon age. For example, thoracic injuries in adults had significantly higher MRMAIS than such injuries among 5- to 9-year-olds and 10- to 14-year-olds (P =.04; P <.01). Furthermore, though AIS was positively correlated with MR within each age group, less correlation was seen for children than for adults. Large MR variations were seen within each AIS grade, with some lower AIS severity injuries demonstrating greater MRs than higher AIS severity injuries. As an example, MRMAIS in 0- to 18-year-olds was 0.4% for an AIS 3 radius fracture versus 1.4% for an AIS 2 vault fracture.

Conclusions: Trauma severity metrics are important for outcome prediction models and can be used in pediatric triage algorithms and other injury research. Trauma severity may vary for similar injuries based upon developmental stage, and this difference should be reflected in severity metrics. The MR-based data-driven determination of injury severity in pediatric occupants of different age cohorts provides a supplement or an alternative to AIS severity classification for pediatric occupants in MVCs.  相似文献   
105.
Globally, 6.4 million tons of fishing gear are lost in the oceans annually. This gear (i.e., ghost nets), whether accidently lost, abandoned, or deliberately discarded, threatens marine wildlife as it drifts with prevailing currents and continues to entangle marine organisms indiscriminately. Northern Australia has some of the highest densities of ghost nets in the world, with up to 3 tons washing ashore per kilometer of shoreline annually. This region supports globally significant populations of internationally threatened marine fauna, including 6 of the 7 extant marine turtles. We examined the threat ghost nets pose to marine turtles and assessed whether nets associated with particular fisheries are linked with turtle entanglement by analyzing the capture rates of turtles and potential source fisheries from nearly 9000 nets found on Australia's northern coast. Nets with relatively larger mesh and smaller twine sizes (e.g., pelagic drift nets) had the highest probability of entanglement for marine turtles. Net size was important; larger nets appeared to attract turtles, which further increased their catch rates. Our results point to issues with trawl and drift‐net fisheries, the former due to the large number of nets and fragments found and the latter due to the very high catch rates resulting from the net design. Catch rates for fine‐mesh gill nets can reach as high as 4 turtles/100 m of net length. We estimated that the total number of turtles caught by the 8690 ghost nets we sampled was between 4866 and 14,600, assuming nets drift for 1 year. Ghost nets continue to accumulate on Australia's northern shore due to both legal and illegal fishing; over 13,000 nets have been removed since 2005. This is an important and ongoing transboundary threat to biodiversity in the region that requires attention from the countries surrounding the Arafura and Timor Seas. Entender las Fuentes y Efectos de Equipo de Pesca Abandonado, Perdido y Desechado sobre las Tortugas Marinas del Atlántico Norte  相似文献   
106.
107.
Road mortality is a widely recognized but rarely quantified threat to the viability of amphibian populations. The global extent of the problem is substantial and factors affecting the number of animals killed on highways include life‐history traits and landscape features. Secondary effects include genetic isolation due to roads acting as barriers to migration. Long‐term effects of roads on population dynamics are often severe and mitigation methods include volunteer rescues and under‐road tunnels. Despite the development of methods that reduce road kill in specific locations, especially under‐road tunnels and culverts, there is scant evidence that such measures will protect populations over the long term. There also seems little likelihood that funding will be forthcoming to ameliorate the problem at the scale necessary to prevent further population declines. Efectos de la Mortalidad en Carreteras y Medidas de Mitigación en Poblaciones de Anfibios Beebee  相似文献   
108.
Bangladesh is on target for achieving the Millennium Development Goal 4 relating to infant and under-five mortality because of very rapid reduction in mortality in recent years. But this rate of reduction may be difficult to sustain and may hamper the achievement of Millennium Development Goal 4. Therefore,the main objective of this paper is to discuss and compare the different covariates of infant and under-five mortality in the context of overall country, urban and rural levels of Bangladesh using discriminant analysis. For this, the data are taken from Bangladesh Demographic and Health Survey, 2004. In discriminant analysis,the stepwise procedure has been picked up and only the significant variables are ranked according to the rank of Wilk's Lambda values. The canonical discriminant function coefficients (unstandardized and standardized) for the predictor variables have also been calculated. Both the results show that breastfeeding is the most important variable in discriminating the two groups of mothers,i.e., mothers experiencing to infant mortality or not and mothers experiencing to under-five mortality or not. The related results of discriminant function also indicate that the discriminant function is statistically significant and discriminates well. Therefore, improvements in the health system are essential for promoting the breastfeeding practices (both inclusive and exclusive), which may be the effective strategies to reach families and communities with targeted messages and information.  相似文献   
109.
利用成都市2014~2016年逐日呼吸系统疾病和心脑血管疾病死亡资料、同期气象资料和PM2.5日均浓度和每日臭氧最大8h平均浓度(O3)资料,采用分布滞后模型以及广义相加模型中的独立效应模型、非参数二元响应模型和温度分层模型探究了成都市气温、PM2.5和O3单效应,以及气温与PM2.5(或O3)交互作用对当地呼吸和心脑血管疾病死亡人数的影响.单效应分析结果表明,气温与两种疾病死亡人数的累计暴露-反应关系均呈反“J”型分布,最适温度在22.2℃,该温度对应的疾病死亡人数最少;累积滞后1d的PM2.5(或O3)对应的健康风险最大,此时,PM2.5和O3浓度每升高10μg/m3,呼吸系统疾病死亡风险分别增加0.58%和0.54%,心脑血管疾病死亡风险分别增加0.35%和0.66%.分季节研究结果表明,PM2.5对两种疾病死亡影响的健康风险冬季最高,而O3的健康风险在秋季最显著.交互作用的研究结果表明,高温与高浓度的PM2.5(或O3)对疾病死亡的影响存在协同放大效应,当气温高于22.2℃时,PM2.5和O3浓度每升高10μg/m3,对应的呼吸系统疾病死亡风险分别增加2.30%和1.14%,心脑血管疾病死亡风险分别增加1.09%和1.03%.研究结果提示O3对人群健康的影响也不容忽视,应该引起足够的重视.  相似文献   
110.
Abstract

In light of the practical need for research to inform policy in Beijing, this study evaluates the economic cost of the impact of PM10 pollution in Beijing from 2001 to 2006, taking health as the main impact, and mortality as the main outcome. Based on the literature review, this study adopts relatively conservative parameters as the basis for calculating the health impacts. It concludes that nearly 30% of mortality among registered residents above age 30 in Beijing can be attributed to PM10 pollution, and that the economic cost equals 0.8%–1.2% of the city’s GDP over the same period. This is lower than the results of previous studies, but still high enough to warrant a commitment to solve the city’s air pollution problem.  相似文献   
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