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51.
Today there are more than 80,000 chemicals in commerce and the environment. The potential human health risks are unknown for the vast majority of these chemicals as they lack human health risk assessments, toxicity reference values, and risk screening values. We aim to use computational toxicology and quantitative high‐throughput screening (qHTS) technologies to fill these data gaps, and begin to prioritize these chemicals for additional assessment. In this pilot, we demonstrate how we were able to identify that benzo[k]fluoranthene may induce DNA damage and steatosis using qHTS data and two separate adverse outcome pathways (AOPs). We also demonstrate how bootstrap natural spline‐based meta‐regression can be used to integrate data across multiple assay replicates to generate a concentration–response curve. We used this analysis to calculate an in vitro point of departure of 0.751 μM and risk‐specific in vitro concentrations of 0.29 μM and 0.28 μM for 1:1,000 and 1:10,000 risk, respectively, for DNA damage. Based on the available evidence, and considering that only a single HSD17B4 assay is available, we have low overall confidence in the steatosis hazard identification. This case study suggests that coupling qHTS assays with AOPs and ontologies will facilitate hazard identification. Combining this with quantitative evidence integration methods, such as bootstrap meta‐regression, may allow risk assessors to identify points of departure and risk‐specific internal/in vitro concentrations. These results are sufficient to prioritize the chemicals; however, in the longer term we will need to estimate external doses for risk screening purposes, such as through margin of exposure methods.  相似文献   
52.
Research into values at an early age has only started recently, although it has expanded quickly and dynamically in the past years. The purpose of this article is twofold: First, it provides an introduction to a special section that aims to help fill the gap in value development research. The special section brings together four new longitudinal and genetically informed studies of value development from the beginning of middle childhood through early adulthood. Second, this article reviews recent research from this special section and beyond, aiming to provide new directions to the field. With new methods for assessing children's values and an increased awareness of the role of values in children's and adolescents' development, the field now seems ripe for an in‐depth investigation. Our review of empirical evidence shows that, as is the case with adults, children's values are organized based on compatibilities and conflicts in their underlying motivations. Values show some consistency across situations, as well as stability across time. This longitudinal stability tends to increase with age, although mean changes are also observed. These patterns of change seem to be compatible with Schwartz's (1992) theory of values (e.g., if the importance of openness to change values increases, the importance of conservation values decreases). The contributions of culture, family, peers, significant life events, and individual characteristics to values are discussed, as well as the development of values as guides for behavior.  相似文献   
53.
The estimation of the mixtures of regression models is usually based on the normal assumption of components and maximum likelihood estimation of the normal components is sensitive to noise, outliers, or high-leverage points. Missing values are inevitable in many situations and parameter estimates could be biased if the missing values are not handled properly. In this article, we propose the mixtures of regression models for contaminated incomplete heterogeneous data. The proposed models provide robust estimates of regression coefficients varying across latent subgroups even under the presence of missing values. The methodology is illustrated through simulation studies and a real data analysis.  相似文献   
54.
市场经济负面影响的日益显现及西方所谓普世价值的冲击,使不少国人陷入价值错乱、虚无的状态,亟待对其加强价值引导。社会主义核心价值的提出及构建可谓正当其时。价值与核心价值的构建,必须遵循人性维度。运用理性思维去把握人性,形成科学的人性理论,并将其付之于现实生活予以检验,把握人性的真实,才能为核心价值构建奠定人性的坚实基石。  相似文献   
55.
Due to destructiveness of natural disasters, restriction of disaster scenarios and some human causes, missing data usually occur in disaster decision-making problems. In order to estimate missing values of alternatives, this paper focuses on imputing heterogeneous attribute values of disaster based on an improved K nearest neighbor imputation (KNNI) method. Firstly, some definitions of trapezoidal fuzzy numbers (TFNs) are introduced and three types of attributes (i.e. linguistic term sets, intervals and real numbers) are converted to TFNs. Then the correlated degree model is utilized to extract related attributes to form instances that will be used in K nearest neighbor algorithm, and a novel KNNI method merging with correlated degree model is presented. Finally, an illustrative example is given to verify the proposed method and to demonstrate its feasibility and effectiveness.  相似文献   
56.
堪称当代日本中国学代表的村田雄二郎出版了大量涉华著述,从社会学、政治学等角度对鸦片战争至清末的清廷国家观的变迁做了阐释,由"天朝定制"、"家国同构"、"地方自治与中央集权"等论点构成了其理论架构,与我国史学界的相关研究相比,角度新颖,确有可借鉴之处。另一方面,日本学者的立场也不乏偏颇之处,作者在对其批驳的基础上提出了自己的观点。  相似文献   
57.
We introduce the problem of estimation of the parameters of a dynamically selected population in an infinite sequence of random variables and provide its application in the statistical inference based on record values from a non stationary scheme. We develop unbiased estimation of the parameters of the dynamically selected population and evaluate the risk of the estimators. We provide comparisons with natural estimators and obtain asymptotic results. Finally, we illustrate the applicability of the results using real data.  相似文献   
58.
Work values might be proximal predictors of individuals' late‐career intentions because they serve as guiding principles for the selection, evaluation, and justification of vocational behavior. The purpose of this study was to examine the relationship between work values and post‐retirement work intentions. The authors investigated individual work values within the structure of 4 higher order values elaborated on by Schwartz et al. ( 2012 ). Relationships between work values and 4 types of post‐retirement work intentions were examined. Data from 1,071 employees of a German logistics company were used to test the hypotheses. The results of a structural equation model indicated that work values were differentially related to the 4 types of post‐retirement work intentions. The identified work value–work type combinations add to the literature on post‐retirement work. Practice implications for promoting positive individual and organizational outcomes are drawn from the results.  相似文献   
59.
我国企业品牌定位的五层次研究   总被引:2,自引:0,他引:2  
近年来中国企业的品牌建设取得了可喜的成绩,出现了许多优秀品牌,这些品牌凭借独特、合适的定位取得了成功。但企业在品牌定位方面存在许多误区,如把品牌定位看作产品定位、品牌定位模糊,缺乏差异性和明确的核心价值、品牌盲目延伸导致定位混淆等问题。因此,产品品牌定位必须树立正确的定位理念,应用正确的品牌定位方法。正确的品牌定位方法可分为产品特征定位、物质利益定位、情感利益定位、个性定位以及价值观定位共五个层次。  相似文献   
60.
The Islamic Movement, which is called in Arabic Al-harakaat al-islamiyya or Al-haraka al-islamiyya, has, since its foundation in the 1970s, placed emphasis on education, especially the dissemination of the Islamic message. After the movement scored significant successes in local authority elections, its influence increased on the ideological guidelines according to which some of the Arab education system is partially or fully shaped. The article discusses the split in the movement within the State of Israel, and the differences between the southern and northern faction. It also compares Islamic education and Arab education within Israel and abroad in Europe, in countries which have large immigrant Moslem populations.

The education system that the Islamic Movement tries to develop symbolizes the complexity of the relations between it and the state authorities. They are aware that the authorities will not help in differentiation and separation and will not cease from the constant supervision of the movement's educational institutions. Therefore, their choice of a synthesis between formal and informal education or of a partition between pedagogic state education and moral study classes, is a rational, calculated choice, taking into consideration the reality of a cultural – ethnic – national minority.  相似文献   

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