Inferring extinction of mammals from sighting records, threats, and biological traits

For species with five or more sightings, quantitative techniques exist to test whether a species is extinct on the basis of distribution of sightings. However, 70% of purportedly extinct mammals are known from fewer than five sightings, and such models do not include some important indicators of the likelihood of extinction such as threats, biological traits, search effort, and demography. Previously, we developed a quantitative method that we based on species' traits in which we used Cox proportional hazards regression to calculate the probability of rediscovery of species regarded as extinct. Here, we used two versions of the Cox regression model to determine the probability of extinction in purportedly extinct mammals and compared the results of these two models with those of stationary Poisson, nonparametric, and Weibull sighting-distribution models. For mammals with five or more sightings, the stationary Poisson model categorized all but two critically endangered (flagged as possibly extinct) species in our data set as extinct, and results with this model were consistent with current categories of the International Union for the Conservation of Nature. The scores of probability of rediscovery for individual species in one version of our Cox regression model were correlated with scores assigned by the stationary Poisson model. Thus, we used this Cox regression model to determine the probability of extinction of mammals with sparse records. On the basis of the Cox regression model, the most likely mammals to be rediscovered were the Montane monkey-faced bat (Pteralopex pulchra), Armenian myotis (Myotis hajastanicus), Alcorn's pocket gopher (Pappogeomys alcorni), and Wimmer's shrew (Crocidura wimmeri). The Cox model categorized two species that have recently disappeared as extinct: the baiji (Lipotes vexillifer) and the Christmas Island pipistrelle (Pipistrellus murrayi). Our new method can be used to test whether species with few records or recent last-sighting dates are likely to be extinct.     

基于结构方程模型的安全管理体系评估与实证分析

为科学评价不同行业安全管理体系的适用性,基于大量文献的统计分析,提出了评估安全管理体系的2个层级指标,并通过构建结构方程模型（SEM）来分析各评价指标的关系,根据模型变量间的效应系数计算出各级指标的权重系数。利用第三方机构评估某房地产企业安全管理体系的原始数据,对比分析使用本文建立的评价指标得到的评估结果,结合理论分析,验证了该评价指标的有效性和适用性,可以合理评估不同行业安全管理体系的水平。     

矿工安全注意力影响因素的SEM研究

为探索矿工安全注意力的影响因素作用路径,寻求合理的干预对策,在文献研究和实地调研基础上,提取矿工安全注意力的衡量指标和影响因素,借助结构方程模型技术验证研究假设,构建修正后的矿工安全注意力影响因素作用路径概念模型图。研究表明:矿工安全注意力的影响因素,即矿工安全意识、矿工工作疲劳、安全信息刺激以及安全监管对矿工安全注意力的衡量指标,即注意专注度、注意广度以及注意转移度都存在路径关系,而且矿工安全注意力的衡量指标之间也存在路径关系。以期通过有效干预影响因素提高矿工安全注意力,降低人因失误导致煤矿安全事故发生的概率。     

民用机场消防指挥员决策能力分析

为研究民用机场消防指挥员决策能力,根据专家意见及相关规章、文件的规定,筛选出文化素质、身体素质、心理素质等18项影响机场消防指挥员决策能力的要素,并采用问卷调查的方式进行调研。运用SPSS 21.0对问卷进行信度分析、效度分析及因子分析,确定民用机场消防指挥员决策能力指标体系。根据该指标体系构建民用机场消防指挥员决策能力结构方程模型,运用Amos 17.0计算各变量的路径系数,进而得到各指标的权重,避免了人为打分方法确定权重的主观性。研究结果为分析民用机场消防指挥员决策能力提供更加准确、合理、可信的评价方法。     

An Evaluation of the NIOSH Lifting Equation: A Psychophysical and Biomechanical Investigation

Using the results of psychophysical and biomechanical experiments, NIOSH (National Institute for Occupational Safety and Health) Recommended Weight Limit (RWL), the Lifting Index (LI), the form of the asymmetry multiplier, and the criterion for compression force were investigated. Analysis of the results indicated a significant difference between the NIOSH RWL and the reported Maximum Acceptable Weight of Lift (MAWL). Contrary to the NIOSH lifting equation, the form of the asymmetry multiplier was found to be non-linear. The overall average of peak compression force on the L5/S1 was 3685 N. Fifty-eight percent of all compression forces reported in the biomechanical experiment were found to exceed the suggested 3400 N set by NIOSH guidelines. These results support previous research findings on the validity of NIOSH guidelines.     

考虑非线性吸附时溶质在有限厚度粘土中的一维扩散解

在采用非线性分段式吸附等温模式的基础上,建立了溶质在粘土中的一维扩散模型,在考虑有限厚度边界及土中溶质背景浓度的条件下得到了相应的解.模型引入了移动边界以说明当溶质在粘土孔隙水中的浓度达到某一较高值后,阻滞因子将发生显著变化.算例分析表明,该模型和考虑经典非线性吸附等温线得到的结果相差不大,这进一步说明了该模型的合理性.考虑非线性吸附效应对溶质迁移有重要影响.在较高溶质浓度下采用线性吸附等温模式会得到偏不安全的结果.该解相对较简单,并可用于验证各种数值模型、拟合试验数据等.     

Adsorption of mercury on laterite from Guizhou Province, China

The adsorption behaviors of Hg(Ⅱ) on laterite from Guizhou Province,China,were studied and the adsorption mechanism was discussed.The results showed that different mineral compositons in the laterite will cause differences in the adsorption capacity of laterite to Hg(Ⅱ).Illite and non-crystalloids are the main contributors to enhancing the adsorption capacity of laterite to Hg(Ⅱ).The pH of the solution is an important factor affecting the adsorption of Hg(Ⅱ) on laterite.The alkalescent environment (pH 7-9) ...     

钢渣吸附剂吸附机理的研究

采用间歇振荡法,研究了钢渣吸附模式、选择性以及等温吸附方程。结果表明,钢渣对阳离子的吸附容量远远大于对阴离子的吸附容量,其吸附模式属于离子交换;其对重金属离子具有一定的吸附选择性,其选择性能与离子的电性、电价、离子半径和水化热等因素有关;钢渣吸附Pb2＋是单层吸附,符合Langmuir等温吸附方程。     

Will progress in science and technology avert or accelerate global collapse? A critical analysis and policy recommendations

Industrial society will move towards collapse if its total environmental impact (I), expressed either in terms of energy and materials use or in terms of pollution, increases with time, i.e., dI/dt > 0. The traditional interpretation of the I = PAT equation reflects the optimistic belief that technological innovation, particularly improvements in eco-efficiency, will significantly reduce the technology (T) factor, and thereby result in a corresponding decline in impact (I). Unfortunately, this interpretation of the I = PAT equation ignores the effects of technological change on the other two factors: population (P) and per capita affluence (A). A more heuristic formulation of this equation is I = P(T)·A(T)·T in which the dependence of P and A on T is apparent. From historical evidence, it is clear that technological revolutions (tool-making, agricultural, and industrial) have been the primary driving forces behind successive population explosions, and that modern communication and transportation technologies have been employed to transform a large proportion of the world’s inhabitants into consumers of material- and energy-intensive products and services. In addition, factor analysis from neoclassical growth theory and the rebound effect provide evidence that science and technology have played a key role in contributing to rising living standards. While technological change has thus contributed to significant increases in both P and A, it has at the same time brought about considerable eco-efficiency improvements. Unfortunately, reductions in the T-factor have generally not been sufficiently rapid to compensate for the simultaneous increases in both P and A. As a result, total impact, in terms of energy production, mineral extraction, land-use and CO₂ emissions, has in most cases increased with time, indicating that industrial society is nevertheless moving towards collapse. The belief that continued and even accelerated scientific research and technological innovation will automatically result in sustainability and avert collapse is at best mistaken. Innovations in science and technology will be necessary but alone will be insufficient for sustainability. Consequently, what is most needed are specific policies designed to decrease total impact, such as (a) halting population growth via effective population stabilization plans and better access to birth control methods, (b) reducing total matter-energy throughput and pollution by removing perverse subsidies, imposing regulations that limit waste discharges and the depletion of non-renewable resources, and implementing ecological tax reform, and (c) moving towards a steady-state economy in which per-capita affluence is stabilized at lower levels by replacing wasteful conspicuous material consumption with social alternatives known to enhance subjective well-being. While science and technology must play an important role in the implementation of these policies, none will be enacted without a fundamental change in society’s dominant values of growth and exploitation. Thus, value change is the most important prerequisite for avoiding global collapse.

Factors influencing the quality of rural human settlements in a peripheral metropolitan area based on a structural equation model: A case study from Beijing

Rural human settlement is a significant indicator of the living standards of rural residents, and its improvement can contribute to promoting the positive interaction between inhabited environment and the social, economic, and resource environment in the countryside. Based on 557 valid questionnaires of satisfaction evaluation of human settlement in the peripheral metropolitan area of Beijing, this paper analyzed the elemental characteristics and factors influencing human settlement quality using multivariate statistical analysis and a structural equation model. The result shows that, first, the rural residents in a peripheral metropolitan area of Beijing are generally satisfied with the quality of human settlement (satisfaction rate is 66.2%). Specifically, the natural and social environment of the countryside is excellent and harmonious and corresponding standard of countryside infrastructure is advanced, but the quality of public services and follow-up management of facilities are in urgent need of improvement and the imbalance between revenue and expenditure of rural households has led to a continuous increase in the pressures of life. Second, factors such as social atmosphere, appearance of the village, entertainment, living costs, fundamental public services, and production costs have significant effects on human settlement quality in this peripheral metropolitan area, with social atmosphere as the main one. Living costs and supporting services are the main constraints to improvement in the quality of human settlement.