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51.
52.
This paper assesses factors that potentially influence the volatility of crude oil prices and the possible linkage between this volatility and agricultural commodity markets. Stochastic volatility models are applied to weekly crude oil, corn, and wheat futures prices from November 1998 to January 2009. Model parameters are estimated using Bayesian Markov Chain Monte Carlo methods. Speculation, scalping, and petroleum inventories are found to be important in explaining the volatility of crude oil prices. Several properties of crude oil price dynamics are established, including mean-reversion, an asymmetry between returns and volatility, volatility clustering, and infrequent compound jumps. We find evidence of volatility spillover among crude oil, corn, and wheat markets after the fall of 2006. This can be largely explained by tightened interdependence between crude oil and these commodity markets induced by ethanol production. 相似文献
53.
Veronica Barcelona Yunfeng Huang Billy A. Caceres Kevin P. Newhall Qin Hui Jessica P. Cerdea Cindy A. Crusto Yan V. Sun Jacquelyn Y. Taylor 《International journal of molecular sciences》2022,23(16)
Potentially traumatic experiences have been associated with chronic diseases. Epigenetic mechanisms, including DNA methylation (DNAm), have been proposed as an explanation for this association. We examined the association of experiences of trauma with epigenome-wide DNAm among African American mothers (n = 236) and their children aged 3–5 years (n = 232; N = 500), using the Life Events Checklist-5 (LEC) and Traumatic Events Screening Inventory—Parent Report Revised (TESI-PRR). We identified no DNAm sites significantly associated with potentially traumatic experience scores in mothers. One CpG site on the ENOX1 gene was methylome-wide-significant in children (FDR-corrected q-value = 0.05) from the TESI-PRR. This protein-coding gene is associated with mental illness, including unipolar depression, bipolar, and schizophrenia. Future research should further examine the associations between childhood trauma, DNAm, and health outcomes among this understudied and high-risk group. Findings from such longitudinal research may inform clinical and translational approaches to prevent adverse health outcomes associated with epigenetic changes. 相似文献
54.
Fifteen studies of family-school interventions with preschool children conducted between 1980 and 2002, and published in peer-reviewed journals, were reviewed and evaluated according to the criteria developed by the Task Force on Evidence-Based Intervention in School Psychology (Division 16 and Society for the Study of School Psychology Task Force, 2003). Results indicate that family-school interventions with preschool children have taken many forms, have targeted a variety of problems and behaviors, and have generally shown positive effects. Efficacious interventions included parent and teacher training, parent education, and behavioral family therapy. Recommendations for future research include increased methodological rigor, replication and extension of current studies, and the completion of longer-term, follow-up investigations to determine whether gains that are made post-treatment are maintained over time. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
55.
Hui-Chung Wu Ricky Nguyen Mindy Goldsborough Ilana Margalit Cindy Breed Arezou Azarani 《Journal of The Association for Laboratory Automation》2003,8(1):28-30
Automating electrophoresis significantly reduces the time required for loading a large number of samples, increases the speed of electrophoresis analysis, and maximizes the resolution power (clear separation of fragments) of this technique. In addition, automation increases the precision of electrophoresis analysis. Here we demonstrate an automated, high-throughput method of loading 96 samples simultaneously onto an electrophoresis gel, using the Apogent Discoveries Tango™ system and the Invitrogen™ E-Gel® 96 system. 相似文献
56.
Projection or Persuasive Press? Contrary Effects of Personal Opinion and Perceived News Coverage on Estimates of Public Opinion 总被引:1,自引:1,他引:0
This study explores the effects of personal opinion and perceived media content on individuals' assessments of public opinion, as well as the curious phenomenon that, although people perceive public agreement with their own point of view, they tend to see press coverage as disagreeable. One hypothesis, based on theories of projection of personal opinion, predicts that people will see public opinion as much like their own, but a contrary outcome is suggested by 2 interrelated hypotheses, the hostile media effect and the persuasive press inference. Data were collected on 4 issues from a large, representative national sample and provided evidence for all 3 effects. Projection received the most consistent support, but findings indicate that this assimilation effect can be substantially offset by media coverage seen as both disagreeable and influential. 相似文献
57.
The authors examined memory compensation techniques used by older adults from 2 memory status groups, not impaired control (NIC) and mild memory deficit (MMD), both at baseline and across a 6-year (3-wave) interval. The groups were derived from a parent sample of 55- to 85-year-old adults from the Victoria Longitudinal Study (NIC baseline, n = 276; memory > parent sample mean; MMD baseline, n = 79; memory > 1 standard deviation below parent sample mean). Multilevel modeling was used to test 3 research questions concerning differences in initial use of, and 6-year changes and variability in, memory compensation. Initial group differences were observed for both a memory compensation technique and a general compensation indicator. Significant differences in 6-year change patterns were observed for 2 memory compensation techniques (recruitment of human memory assistance, investment of extra effort in memory tasks). Interactions of group status and wave showed that older adults with MMD declined in their use of memory compensation strategies, whereas initially NIC older adults increased their use of compensatory techniques over the 6 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Jackson Christine L.; Colquitt Jason A.; Wesson Michael J.; Zapata-Phelan Cindy P. 《Canadian Metallurgical Quarterly》2006,91(4):884
The 3 studies presented here introduce a new measure of the individual-difference form of collectivism. Psychological collectivism is conceptualized as a multidimensional construct with the following 5 facets: preference for in-groups, reliance on in-groups, concern for in-groups, acceptance of in-group norms, and prioritization of in-group goals. Study 1 developed and tested the new measure in a sample of consultants. Study 2 cross-validated the measure using an alumni sample of a Southeastern university, assessing its convergent validity with other collectivism measures. Study 3 linked scores on the measure to 4 dimensions of group member performance (task performance, citizenship behavior, counterproductive behavior, and withdrawal behavior) in a computer software firm and assessed discriminant validity using the Big Five. The results of the studies support the construct validity of the measure and illustrate the potential value of collectivism as a predictor of group member performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Recent research with the Memory Compensation Questionnaire (MCQ) has examined changes, functions, and correlates of compensatory strategy use in older adults. The twofold aim of this study was to test (a) the hypothesized structure of the MCQ and (b) structural equivalence across age, gender, and time. The 7-scale MCQ was designed to measure 5 compensatory mechanisms and 2 general aspects of compensatory awareness. The authors assembled a 3-wave (6-year) sample (N=521; age=55-85 years) from the Victoria Longitudinal Study. The results of structural equation modeling supported (a) the a priori structure of the MCQ and (b) the inference of measurement invariance across the 3 dimensions. Accordingly, the MCQ is available for measuring self-reported efforts to compensate for everyday memory losses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Cindy Eisner 《Software and Systems Modeling》2005,4(1):14-31
We describe the experience of modeling and formally verifying a software cache algorithm using the model checker RuleBase. Contrary to prevailing wisdom, we used a highly detailed model created directly from the C code itself, rather than a high-level abstract model. 相似文献