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1.
This study assesses the percentage of traumatic fatalities attributable to work-related causes in the US, by cause of death and population demographics. The 1993-1998 Vital Statistics Mortality data from the National Center for Health Statistics were used. There were 848,945 traumatic fatalities (E800-E999) among the general population 16 years or older in the US during this time; of these, 32,044 were work-related accounting for 3.8% of all the fatalities. The work-related percentage varied from 62.7% for machine-related deaths to 0.7% for suicides, from 4.9% for males to 1.0% for females, from 9.8% in Alaska to 1.5% in Arizona, from 4.2% for decedents with 1 to 4 year college educations to 2.9% for decedents with high school or less, from 4.4% for races other than white and black to 2.6% for black. Mean age-at-death was 42 years for work-related vs. 48 years for non-work-related fatalities. This difference is more pronounced for deaths from falls (45 years vs. 78 years). Conversely, victims of work-related homicide were older than non-work-related (41 years vs. 33 years). A more complete understanding of the burden of traumatic fatalities attributable to work-related causes requires consideration of the total work-related percentage, causes of death, and population demographics.  相似文献   

2.
Focusing on the spatial and temporal pattern, evolution law, influencing factors and prediction of regional ecological footprint (EF) is conducive to promoting sustainable development of regional populations, resources, and the environment. Firstly, this study used the EF model to analyze the spatial and temporal patterns and dynamic evolution characteristics of the total ecological footprint (TEF) and the relative contributions of the biological ecological footprint (BEF), energy ecological footprint (EEF), and pollution ecological footprint (PEF) in China from 2000 to 2019. Secondly, the impact of socioeconomic factors on China's TEF was analyzed based on the STIRPAT model. Finally, the future development trend of China's TEF was analyzed by multi-scenario prediction. The results demonstrate that: (1) from 2000 to 2019, the TEF levels of China form three gradient spaces, (2) the BEF is the biggest contributor to EF in most of China's provinces, (3) total energy consumption is the most important positive factor for China's TEF while proportion of tertiary industry in the three industries is the most important negative factor, and (4) maintaining low growth in total energy consumption and high growth in proportion of tertiary industry in the three industries is crucial for limiting the future growth of China's TEF  相似文献   

3.
Resolving the conflicts between biodiversity conservation and socioeconomic development is a global pursuit for the long-run prospects of the human species. Based on Wenchuan County, a typical county in southwestern China, a group of 20 indicators quantifying regional biodiversity and socioeconomic development was established to classify and evaluate the county area spatially. A fuzzy c-means clustering (FCM) algorithm was used as the classification method. Three indices including BD, DL and DR characterizing the value of biodiversity, the level and rate of socioeconomic development of the delineated regions were formulated. The results indicated that Wenchuan County was optimally classified into 4 types of regions (region I to IV). The area percentages of the regions vary widely from 4.3 to 65.7%. The sequences of the regions on biodiversity, socioeconomic development level, and socioeconomic development rate were, respectively, IV > II > III > I, I > III > II > IV and III >I >II >IV. The spatial strategy on coordinating biodiversity conservation and regional development is to develop mainly from the east(I, II, III) and to conserve mainly in the west(IV). Eco-industry, such as eco-tourism and eco-agriculture, need to be emphasized in the process of regional development. The quantitative methods used here may have a wide applicability.  相似文献   

4.
Hydric soil development of riparian wetlands is primarily influenced by the hydrologic connection between the floodplains and the stream channel. Often, the goal of riparian restoration is to revitalize this connectivity through a restructuring of the stream channel and the floodplain; however, the effects of this restructuring on the physical and spatial characteristics of soil properties are rarely considered. The objective of this study was to quantify the impacts of restoration efforts on the spatial characteristics of soil properties by means of a pre‐ and post‐restoration comparison. We determined that the spatial patterns of soil organic matter (SOM) and exchangeable phosphorus (Pex) appeared less variable in the years following restoration than in the years before restoration. Mean SOM significantly decreased after restoration, whereas mean Pex significantly increased. The spatial characteristics and mean concentrations of NO2–NO3 did not differ much between sampling dates. The loss of this spatial patterning in SOM and Pex and the decrease in SOM pools may represent negative impacts of restoration on important ecosystem characteristics. This study demonstrates that soil properties and spatial patterns can be negatively affected by restoration activities potentially hindering ecosystem development and function.  相似文献   

5.

Background

Molecular dynamics (MD) simulations are powerful tools to investigate the conformational dynamics of proteins that is often a critical element of their function. Identification of functionally relevant conformations is generally done clustering the large ensemble of structures that are generated. Recently, Self-Organising Maps (SOMs) were reported performing more accurately and providing more consistent results than traditional clustering algorithms in various data mining problems. We present a novel strategy to analyse and compare conformational ensembles of protein domains using a two-level approach that combines SOMs and hierarchical clustering.

Results

The conformational dynamics of the α-spectrin SH3 protein domain and six single mutants were analysed by MD simulations. The Cα's Cartesian coordinates of conformations sampled in the essential space were used as input data vectors for SOM training, then complete linkage clustering was performed on the SOM prototype vectors. A specific protocol to optimize a SOM for structural ensembles was proposed: the optimal SOM was selected by means of a Taguchi experimental design plan applied to different data sets, and the optimal sampling rate of the MD trajectory was selected. The proposed two-level approach was applied to single trajectories of the SH3 domain independently as well as to groups of them at the same time. The results demonstrated the potential of this approach in the analysis of large ensembles of molecular structures: the possibility of producing a topological mapping of the conformational space in a simple 2D visualisation, as well as of effectively highlighting differences in the conformational dynamics directly related to biological functions.

Conclusions

The use of a two-level approach combining SOMs and hierarchical clustering for conformational analysis of structural ensembles of proteins was proposed. It can easily be extended to other study cases and to conformational ensembles from other sources.  相似文献   

6.
Alien gastropods have caused extensive harm to biodiversity and socioeconomic systems like agriculture and horticulture worldwide. For conservation and management purposes, information on impacts needs to be easily interpretable and comparable, and the factors that determine impacts understood. This study aimed to assess gastropods alien to South Africa to compare impact severity between species and understand how they vary between habitats and mechanisms. Furthermore, we explore the relationship between environmental and socioeconomic impacts, and both impact measures with life‐history traits. We used the Environmental Impact Classification for Alien Taxa (EICAT) and Socio‐Economic Impact Classification for Alien Taxa (SEICAT) to assess impacts of 34 gastropods alien to South Africa including evidence of impact from their entire alien range. We tested for correlations between environmental and socioeconomic impacts per species, and with fecundity and native latitude range using Kendall's tau tests. Kruskal–Wallis tests were used to compare impact magnitude among mechanisms and habitats, respectively. This study presents the first application of EICAT and SEICAT for invertebrates. There was no correlation between environmental impacts and socioeconomic impacts. Habitats did not differ regarding the severity of impacts recorded, but impacts via disease transmission were lower than other mechanisms. Neither fecundity nor native range latitude was correlated with impact magnitude. Despite gastropods being agricultural and horticultural pests globally, resilience of socioeconomic systems makes high impacts uncommon. Environmental systems may be vulnerable to gastropod impacts across habitats, having experienced multiple local extinctions of wetland island snail fauna. South Africa stands out as the only continental country that follows this trend. The knowledge gained on severity and nature of gastropod impacts is useful in risk assessment, which can aid conservation management. To make impact assessments more realistic, we suggest alternative ways of reporting impacts classified under EICAT and SEICAT.  相似文献   

7.
8.
Towards an Integrated Regional Materials Flow Accounting Model   总被引:1,自引:0,他引:1  
A key challenge in attaining regional sustainability is to reduce both the direct and the indirect environmental impacts associated with economic and household activity in the region. Knowing what these flows are and how they change over time is a prerequisite for this task.
This article describes the early development of an integrated regional materials flow accounting framework. The framework is based on a hybrid (material and economic) multiregional input-output model. Using readily available economic and materials data sets together with transport and logistics data, the framework attempts to provide estimates of household resource flows for any U.K. region at quite detailed levels of product and material disaggregation. It is also capable of disaggregating these flows according to specific socioeconomic criteria such as income level or occupation of the head of household. Allied to appropriate energy and life-cycle assessment data sets, the model could, in addition, be used to map both direct and indirect environmental impacts associated with these flows.
The benefits of such an approach are likely to be a considerable reduction of uncertainties in (1) our knowledge of the household metabolism, and hence our predictions of regional household waste generation; (2) our assessment of the impacts of contemplated changes in industrial process siting, and thereby on other aspects of local and regional planning; and (3) our understanding of the impacts of changes in the pattern of demand for different materials and products. It is concluded that the use of such an integrated assessment tool has much to contribute to the debate on regional sustainability.  相似文献   

9.

Background

A comprehensive technique for earthquake-related casualty estimation remains an unmet challenge. This study aims to integrate risk factors related to characteristics of the exposed population and to the built environment in order to improve communities’ preparedness and response capabilities and to mitigate future consequences.

Methods

An innovative model was formulated based on a widely used loss estimation model (HAZUS) by integrating four human-related risk factors (age, gender, physical disability and socioeconomic status) that were identified through a systematic review and meta-analysis of epidemiological data. The common effect measures of these factors were calculated and entered to the existing model’s algorithm using logistic regression equations. Sensitivity analysis was performed by conducting a casualty estimation simulation in a high-vulnerability risk area in Israel.

Results

the integrated model outcomes indicated an increase in the total number of casualties compared with the prediction of the traditional model; with regard to specific injury levels an increase was demonstrated in the number of expected fatalities and in the severely and moderately injured, and a decrease was noted in the lightly injured. Urban areas with higher populations at risk rates were found more vulnerable in this regard.

Conclusion

The proposed model offers a novel approach that allows quantification of the combined impact of human-related and structural factors on the results of earthquake casualty modelling. Investing efforts in reducing human vulnerability and increasing resilience prior to an occurrence of an earthquake could lead to a possible decrease in the expected number of casualties.  相似文献   

10.
齐建超  刘慧平  伊尧国 《生态学报》2017,37(19):6346-6354
时间序列土地利用时空演变规律分析是当前的研究热点之一,通过应用自组织映射神经网络方法进行多时间序列土地利用变化时空一体化表达与演变规律分析,探索区域土地利用变化模式。基于北京市2005、2007、2009、2011、2013年5期土地利用遥感分类数据,构建自组织映射神经网络并利用其聚类和降维可视化功能对5个年份的土地利用数据同时进行训练输出,发现建设用地、耕地、林地、牧草地、园地的聚集模式,并通过对输出神经元进行二次聚类以及土地利用变化轨迹分析,获得北京市郊区5个监测时相土地利用变化的时空演变特征。结果揭示出北京市郊区2005-2013年土地利用变化具有明显的耕地型向建设用地型发展的平原区演变特征,以及向林地型发展的山区演变特征,且各区的发展具有时间上的顺序性;总体上形成6类土地利用演变轨迹。  相似文献   

11.
Plant- and microbially derived carbon (C) are the two major sources of soil organic matter (SOM), and their ratio impacts SOM composition, accumulation, stability, and turnover. The contributions of and the key factors defining the plant and microbial C in SOM along the soil profile are not well known. By leveraging nuclear magnetic resonance spectroscopy and biomarker analysis, we analyzed the plant and microbial C in three soil types using regional-scale sampling and combined these results with a meta-analysis. Topsoil (0–40 cm) was rich in carbohydrates and lignin (38%–50%), whereas subsoil (40–100 cm) contained more proteins and lipids (26%–60%). The proportion of plant C increases, while microbial C decreases with SOM content. The decrease rate of the ratio of the microbially derived C to plant-derived C (CM:P) with SOM content was 23%–30% faster in the topsoil than in the subsoil in the regional study and meta-analysis. The topsoil had high potential to stabilize plant-derived C through intensive microbial transformations and microbial necromass formation. Plant C input and mean annual soil temperature were the main factors defining CM:P in topsoil, whereas the fungi-to-bacteria ratio and clay content were the main factors influencing subsoil CM:P. Combining a regional study and meta-analysis, we highlighted the contribution of plant litter to microbial necromass to organic matter up to 1-m soil depth and elucidated the main factors regulating their long-term preservation.  相似文献   

12.
采矿业是赞比亚一类非常重要的工业 ,大量的开采和选矿作业给周边地区带来了严重的环境问题。导致了该区域内地表水、空气、土壤的污染 ,并对当地人民的身体健康带来威胁。本文主要分析铜矿开采业对赞比亚的社会经济及环境的影响 ,进一步探讨可以保持当地采矿业的可持续发展的有效措施。  相似文献   

13.
Roads are responsible for different negative effects on wildlife, including the isolation of populations and the direct reduction of biodiversity. Millions of animals are killed in traffic every year. Despite that, the influence of animal behaviour on the probability of animal-vehicle collisions has been overlooked by the literature. The blue-black grassquit (Volatinia jacarina) is a small, migratory, dichromatic species. During the breeding period, males vigorously defend small, clustered territories. Here, we investigated how the number of roadkills varied spatially and temporally in relation to the breeding activity, density, and sex of grassquits. We demonstrated that the variation in the movement dynamics and reproductive behaviour of the grassquits are associated with a great number of casualties. Road mortality is higher during the breeding period but is not associated with juvenile dispersion. As expected, males have a higher probability of being road-killed than females, suggesting that territory defence and mate searching may increase the risk of mortality. On the other hand, the clustering of individuals may not increase the risk of road fatalities, suggesting that other environmental attributes may influence the probability of being killed on roads.  相似文献   

14.
While the protected area (PA) covers >15% of the planet's terrestrial land area and continues to expand, factors determining its effectiveness in conserving endangered species are being debated. We investigated the links between direct anthropogenic pressures, socioeconomic settings, and the coverage of vertebrate taxa by China's PA network, and indicated that high socioeconomic status and low levels of human pressure correlate with high species coverage, with threatened mammals more effectively conserved than reptiles or amphibians. Positive links between conservation outcomes and socioeconomic progress appear linked to local livelihood improvements triggering positive perceptions of local PAs—aided further by ecological compensation and tourism schemes introduced in wealthy areas and reinforced by continued positive conservation outcomes. Socioeconomic development of China's less developed regions might assist regional PA efficiency and achievement of the Kunming-Montreal Global Biodiversity Framework, while also addressing potential shortcomings from an insufficient past focus on socioeconomic impacts for biodiversity conservation.  相似文献   

15.
Warmer climates have been associated with reduced bioreactivity of soil organic matter (SOM) typically attributed to increased diagenesis; the combined biological and physiochemical transformation of SOM. In addition, cross‐site studies have indicated that ecosystem regime shifts, associated with long‐term climate warming, can affect SOM properties through changes in vegetation and plant litter production thereby altering the composition of soil inputs. The relative importance of these two controls, diagenesis and inputs, on SOM properties as ecosystems experience climate warming, however, remains poorly understood. To address this issue we characterized the elemental, chemical (nuclear magnetic resonance spectroscopy and total hydrolysable amino acids analysis), and isotopic composition of plant litter and SOM across a well‐constrained mesic boreal forest latitudinal transect in Atlantic Canada. Results across forest sites within each of three climate regions indicated that (1) climate history and diagenesis affect distinct parameters of SOM chemistry, (2) increases in SOM bioreactivity with latitude were associated with elevated proportions of carbohydrates relative to plant waxes and lignin, and (3) despite the common forest type across regions, differences in SOM chemistry by climate region were associated with chemically distinct litter inputs and not different degrees of diagenesis. The observed climate effects on vascular plant litter chemistry, however, explained only part of the regional differences in SOM chemistry, most notably the higher protein content of SOM from warmer regions. Greater proportions of lignin and aliphatic compounds and smaller proportions of carbohydrates in warmer sites' soils were explained by the higher proportion of vascular plant relative to moss litter in the warmer relative to cooler forests. These results indicate that climate change induced decreases in the proportion of moss inputs not only impacts SOM chemistry but also increases the resistance of SOM to decomposition, thus significantly altering SOM cycling in these boreal forest soils.  相似文献   

16.
Breast cancer is one of the most commonly diagnosed cancers worldwide. The primary aim of this work is the study of breast cancer disparity among Chinese women in urban vs. rural regions and its associations with socioeconomic factors. Data on breast cancer incidence were obtained from the Chinese cancer registry annual report (2005–2009). The ten socioeconomic factors considered in this study were obtained from the national population 2000 census and the Chinese city/county statistical yearbooks. Student’s T test was used to assess disparities of female breast cancer and socioeconomic factors in urban vs. rural regions. Pearson correlation and ordinary least squares (OLS) models were employed to analyze the relationships between socioeconomic factors and cancer incidence. It was found that the breast cancer incidence was significantly higher in urban than in rural regions. Moreover, in urban regions, breast cancer incidence remained relatively stable, whereas in rural regions it displayed an annual percentage change (APC) of 8.55. Among the various socioeconomic factors considered, breast cancer incidence exhibited higher positive correlations with population density, percentage of non-agriculture population, and second industry output. On the other hand, the incidence was negatively correlated with the percentage of population employed in primary industry. Overall, it was observed that higher socioeconomic status would lead to a higher breast cancer incidence in China. When studying breast cancer etiology, special attention should be paid to environmental pollutants, especially endocrine disruptors produced during industrial activities. Lastly, the present work’s findings strongly recommend giving high priority to the development of a systematic nationwide breast cancer screening program for women in China; with sufficient participation, mammography screening can considerably reduce mortality among women.  相似文献   

17.
Self-organizing maps (SOM) constitute an alternative to classical clustering methods because of its linear run times and superior performance to deal with noisy data. Nevertheless, the clustering obtained with SOM is dependent on the relative sizes of the clusters. Here, we show how the combination of SOM with hierarchical clustering methods constitutes an excellent tool for exploratory analysis of massive data like DNA microarray expression patterns.  相似文献   

18.
江伟康  吴隽宇 《生态学报》2021,41(5):1747-1757
经济发展与人口集聚引起的土地利用变化对一个地区的生态环境影响显著,生境质量评价在一定程度上可以反映区域生物多样性的状况。分析地区生境质量与社会经济、人口密度的关系,能够为区域生态安全及可持续发展提供科学依据。运用InVEST模型,以粤港澳大湾区2005、2010、2015、2018年四期土地利用数据分析生境质量的时空演变特征,结合社会经济及人口分布数据探究各地区城市发展与生境质量的权衡关系,并预测2030年大湾区不同情景下生境质量状况。结果表明:(1)2005-2018年粤港澳大湾区整体生境质量逐年降低,呈现出中部低、四周高的环状分布,生境破碎、建设用地增加是生境质量下降的主要原因。(2)珠三角九市生境质量与地区总GDP呈弱负相关,与第一产业产值呈中等正相关,与第二产业产值呈中等负相关,与第三产业产值呈弱正相关。(3)粤港澳大湾区生境质量与人口密度存在较大的不平衡,最主要的空间为高生境质量-低人口密度、低生境质量-高人口密度两种类型。(4)通过空间管制分区,预测2030年大湾区规划保护情景下大湾区平均生境质量较2018上升0.04,达到0.599,生境质量有明显改善。  相似文献   

19.
以江苏南部农村工业发达地区的吴江市为研究范例,采用系统动力学模型模拟分析方法,分析农村工业发展对农业生态系统的影响。结果表明,农村工业的发展对农业生态系统有正负两方面的影响,正影响表现为提高农民收入、增加农业投入、转移农村劳力等;负影响表现为导致耕地减少和环境污染等。农村工业实力增强后,若其产值利润以一定的比例用于发展农业和治理环境,将能减弱或避免农村工业给农业生态系统带来的负影响,达到农村工业与农业的协调发展。  相似文献   

20.
基于DMSP/OLS影像的我国主要城市群空间扩张特征分析   总被引:4,自引:0,他引:4  
20世纪90年代以来,随着中国城市化步伐的加快,城市用地空间扩张极为明显。采用1992、1995、2000、2005、2009年5期的夜间灯光影像数据提取了京津冀、长江三角洲和珠江三角洲城市群的城市像元,并从空间扩张强度、扩张类型以及方向性空间扩张特征3个方面对三大城市群城市用地的空间扩张特征进行了分析,同时还从社会经济方面对城市群空间扩张的驱动因素进行了讨论。结果表明,三大城市群的空间扩张特征既存在共性也存在明显的差异,同时社会经济的快速发展对城市用地的扩张具有明显的驱动作用,为进一步推动中国城市化进程提供了数据支撑。  相似文献   

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