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91.
《Journal Of Human Behavior In The Social Environment》2013,23(4):91-118
ABSTRACT This study examined youth self-reported data from a 4-year longitudinal study of 5th and 8th grade youth and their parents. Relationships between neighborhood conditions, parenting, and youth antisocial behavior were tested using structural equation modeling. The findings of this study appear to suggest there are two social forces that affect youth antisocial behavior: parenting and neighborhood conditions. Higher levels of parental acceptance and monitoring are directly and significantly associated with lower levels of youth antisocial behavior, as are higher levels of community social integration and lower levels of youth loneliness. Overall, it was found that some measures of neighborhood conditions and some measures of parenting were relatively equally predictive of youth antisocial behavior. Other measures of neighborhood conditions were predictive of parenting, but not strongly enough to also impact adolescent functioning. 相似文献
92.
Sharon Judge 《Journal of Children and Poverty》2013,19(1):1-19
Early exposure to multiple risk factors is related to an elevated risk for academic difficulty. Thus, it is important to promote academic resilience as early as possible and to identify factors that support resilience. Given the positive relation between early literacy skills and later academic outcomes, examining resilience in reading is important. This study examined, first, whether the reading gap widens or narrows for below-average and above-average, at-risk children during the first four years of school; and, second, what protective factors predict reading achievement over time from kindergarten through the end of third grade. Results indicated that as a group, low-achieving children made smaller gains in reading than high-achieving children over the first four years of school. In addition, participation in center-based prekindergarten care, plus more access to books in the home, better interpersonal skills, and fewer poor physical conditions immediately surrounding elementary schools served as protective factors for at-risk children's early literacy development. 相似文献
93.
The main goal of this study was to examine the direct and moderating effects of trustworthiness and modeling on adolescent siblings' adjustment. Data were collected from 438 families including a mother, a younger sibling in fifth, sixth, or seventh grade (M = 11.6 years), and an older sibling (M = 14.3 years). Respondents completed Web‐based surveys describing sibling conflict and warmth. Siblings reported on trustworthiness and modeling, and mothers described adjustment. Sibling conflict was directly associated with internalizing and externalizing behaviors for both siblings. The older siblings' reports of trustworthiness were directly associated with the outcome measures. The younger siblings' reports of trustworthiness were less directly associated, but a possible salutary effect was most evident under the highest levels of sibling conflict or warmth. Higher sibling modeling was a risk factor for adjustment problems in relations characterized by high conflict. Results support exploring trustworthiness as a key dimension of sibling relations. 相似文献
94.
Edson Zangiacomi Martinez Davi Casale Aragon Jorge Alberto Achcar 《Journal of applied statistics》2011,38(6):1303-1309
It is known that patients may cease participating in a longitudinal study and become lost to follow-up. The objective of this article is to present a Bayesian model to estimate the malaria transition probabilities considering individuals lost to follow-up. We consider a homogeneous population, and it is assumed that the considered period of time is small enough to avoid two or more transitions from one state of health to another. The proposed model is based on a Gibbs sampling algorithm that uses information of lost to follow-up at the end of the longitudinal study. To simulate the unknown number of individuals with positive and negative states of malaria at the end of the study and lost to follow-up, two latent variables were introduced in the model. We used a real data set and a simulated data to illustrate the application of the methodology. The proposed model showed a good fit to these data sets, and the algorithm did not show problems of convergence or lack of identifiability. We conclude that the proposed model is a good alternative to estimate probabilities of transitions from one state of health to the other in studies with low adherence to follow-up. 相似文献
95.
Quantitative Approaches in Use to Assess Cancer Risk 总被引:4,自引:0,他引:4
Elizabeth L. Anderson 《Risk analysis》1983,3(4):277-295
96.
基于产业集群的企业重点投资地区决策的仿真 总被引:1,自引:0,他引:1
用多Agent仿真技术,研究了基于产业集群的台资IT企业在大陆重点投资地区的决策问题。提出了针对这一问题的、将集群竞争力评价的GEM模型、多Agent仿真技术及演化博弈相结合的思路与方法。仿真模型对集群的研究方法以及多Agent的应用领域有拓展意义,而仿真发现与结论可为政府制定有关政策提供参考。 相似文献
97.
贾晓峰 《太原理工大学学报(社会科学版)》2000,18(1):40-42
本文认为,当前非数学专业的微积分教学改革,应特别强调微积分的数学建模方法和计算功能,强调对数学原理和背景的介绍.为此,作者以"启发应用意识,提高应用能力"为宗旨,提出从教材到教学法直至成绩考核方法的一整套教学改革方案. 相似文献
98.
张莲云 《江汉大学学报(人文科学版)》2000,19(3):60-65
化学实验不是一种纯粹的感性认识过程,它是在理论思维的指导下对化学的自然本质进行“解剖”的过程,是理论思维的物化。 相似文献
99.
Effects of the Mechanism of Receptor-Mediated Gene Expression on the Shape of the Dose-Response Curve 总被引:1,自引:0,他引:1
A mathematical model of receptor-mediated gene expression that includes receptor binding of natural and xenobiotic ligands, protein synthesis and degradation, and metabolism of the xenobiotic ligand was created to identify the determinants of the shape of the dose-response profile. Values of the model's parameters were varied to reflect alternative mechanisms of expression of the protein. These assumptions had dramatic effects on the computed response to a bolus dose of the xenobiotic ligand. If all processes in the model exhibit hyperbolic kinetics, the dose-response curves can appear sigmoidal but actually be linear with a positive slope at low doses. The slope of the curve only approached zero at low dose, indicative of a threshold for response, if binding of the xenobiotic ligand to the receptor exhibited positive cooperativity (ligand binding at one site increases the affinity for ligand at another binding site on the receptor). Positive cooperativity in the rate-limiting step of protein synthesis produced dose-response curves which were "U-shaped" at low doses, also indicative of a threshold. Positive cooperativity in the metabolism of the xenobiotic ligand produced dose-response curves that increased more rapidly than linearly with increasing dose. The model illustrates the fact that response cannot be predicted from qualitative mechanistic arguments alone; any assessment of risk to health from xenobiotic chemicals must be based on a detailed quantitative examination of the kinetic behavior of each chemical species individually. 相似文献
100.
In this paper we compare expectations derived from 10 different human physiologically based pharmacokinetic models for perchloroethylene with data on absorption via inhalation, and concentrations in alveolar air and venous blood. Our most interesting finding is that essentially all of the models show a time pattern of departures of predictions of air and blood levels relative to experimental data that might be corrected by more sophisticated model structures incorporating either (a) heterogeneity of the fat compartment (with respect to either perfusion or partition coefficients or both) or (b) intertissue diffusion of perchloroethylene between the fat and muscle/VRG groups. Similar types of corrections have recently been proposed to reduce analogous anomalies in the fits of pharmacokinetic models to the data for several volatile anesthetics.(17-20) A second finding is that models incorporating resting values for alveolar ventilation in the region of 5.4 L/min seemed to be most compatible with the most reliable set of perchloroethylene uptake data. 相似文献