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161.
The rise in human life expectancy has involved declines in intrinsic and extrinsic mortality processes associated, respectively, with senescence and environmental challenges. To better understand the factors driving this rise, we apply a two-process vitality model to data from the Human Mortality Database. Model parameters yield intrinsic and extrinsic cumulative survival curves from which we derive intrinsic and extrinsic expected life spans (ELS). Intrinsic ELS, a measure of longevity acted on by intrinsic, physiological factors, changed slowly over two centuries and then entered a second phase of increasing longevity ostensibly brought on by improvements in old-age death reduction technologies and cumulative health behaviors throughout life. The model partitions the majority of the increase in life expectancy before 1950 to increasing extrinsic ELS driven by reductions in environmental, event-based health challenges in both childhood and adulthood. In the post-1950 era, the extrinsic ELS of females appears to be converging to the intrinsic ELS, whereas the extrinsic ELS of males is approximately 20 years lower than the intrinsic ELS. 相似文献
162.
Substance use among older youth transitioning from foster care: Examining the protective effects of religious and spiritual capital 下载免费PDF全文
Lionel D. Scott Jr. David R. Hodge Tony White Michelle R. Munson 《Child & Family Social Work》2018,23(3):399-407
Among older youth transitioning from the foster care system, this longitudinal study examined the association of religious and spiritual capital to substance use in the past year at age 19. Participants consisted of African American (N = 179) and White non‐Hispanic (N = 133) older youth in foster care. Drawing from social capital theory, it was posited that religious service attendance (a proxy for religious capital) and belief in a spiritual force (a proxy for spiritual capital) would be inversely associated with substance use. Multiple logistic regression results indicated support for the first and second hypothesis for White foster youth only. Among White foster youth, more frequent religious service attendance and greater belief in a spiritual force were associated with a lower likelihood of illegal substance and polysubstance use. No association between religious or spiritual capital and substance use was found among African American foster youth. The findings underscore the importance of conducting spiritual assessments to help ensure older foster youth who have strong religious or spiritual orientations are in environments where they are accommodated and supported. 相似文献
163.
This paper addresses the problem of open order rescheduling in a job shop. Results are reported of experiments conducted in a simulation model of an 8-machine job shop. Four different order updating policies are examined. The due-date process is modeled to include several realistic features about the pattern of due-date variability. These features are parameterized and tested at several levels. Tardiness results indicate that open order rescheduling is beneficial only when allowances are loosely set. The results indicate that inventory performance is improved by order rescheduling, particularly in cases when due dates are revised to earlier times than originally forecast. 相似文献
164.
David Rutkowski Leslie Rutkowski Justin Wild Nathan Burroughs 《Journal of Children and Poverty》2018,24(1):47-67
In the current paper, we employ the most recent Programme for International Student Assessment (PISA) data to calculate a less-biased estimate of poverty on US achievement. The PISA was specifically chosen as it is an assessment removed from a specific curriculum and instead focuses on concepts that students should know in order to participate in a global economy. Using a propensity score matching approach, our findings suggest that US students in poverty have notable educational attainment deficiencies compared to a matched group of students who are not in poverty. In other words, when we select two students who have a great deal in common but for the fact that one comes from a poverty background, the student in poverty is expected to perform nearly 28 points, or about a quarter of a standard deviation lower, on the PISA assessment. In real terms, this puts math achievement for children not in poverty on-par with the Organisation for Economic Co-operation and Development (OECD) average, while children in poverty are well below the OECD average. 相似文献
165.
Negative (But Not Positive) Parenting Interacts with Infant Negative Affect to Predict Infant Approach: Evidence of Diathesis‐Stress 下载免费PDF全文
Jacob B. Holzman Nicole M. Burt Erin S. Edwards Leanna D. Rosinski David J. Bridgett 《Infancy》2018,23(3):471-480
Temperament by parenting interactions may reflect that individuals with greater risk are more likely to experience negative outcomes in adverse contexts (diathesis‐stress) or that these individuals are more susceptible to contextual influences in a “for better or for worse” pattern (differential susceptibility). Although such interactions have been identified for a variety of child outcomes, prior research has not examined approach characteristics—excitement and approach toward pleasurable activities—in the first year of life. Therefore, this study investigated whether 6‐month maternal reported infant negative affect—a phenotypic marker of risk/susceptibility—interacted with 8‐month observed parenting behaviors (positive parenting, negative parenting) to predict 12‐month infant behavioral approach. Based on a sample of mothers and their infants (N = 150), results indicated that negative parenting was inversely associated with subsequent approach for infants with high, but not low, levels of negative affect. Similar results did not occur regarding positive parenting. These findings better fit a diathesis‐stress model rather than a differential susceptibility model. Implications and limitations of these findings are discussed. 相似文献
166.
Infant Sex Moderates the Effects of Maternal Pre‐ and Postnatal Stress on Executive Functioning at 8 Months of Age 下载免费PDF全文
Saara Nolvi Henri Pesonen David J. Bridgett Riikka Korja Eeva‐Leena Kataja Hasse Karlsson Linnea Karlsson 《Infancy》2018,23(2):194-210
Previous studies report that early life stress, including maternal pre‐ and postnatal stress, has adverse effects on cognitive development and that these associations might be sex‐specific. However, no studies exist on early life stress and infant executive functioning (EF). The aim of this study was to examine the relationship between maternal pre‐ and postnatal stress and infant EF, and whether these associations are moderated by infant sex. Maternal prenatal depressive, general anxiety, and pregnancy‐specific anxiety symptoms were measured three times, and postnatal depressive and general anxiety symptoms were measured 6 months postpartum. Infant EF was assessed with a modified A‐not‐B task 8 months postpartum (N = 214). Maternal postnatal general anxiety predicted poorer EF in girls in comparison with boys. Moreover, there was a trend toward an interaction between prenatal anxiety and infant sex such that prenatal anxiety predicted infant EF differently in girls and in boys. No association was found between depressive symptoms or pregnancy‐specific anxiety symptoms and infant EF. These findings suggest that maternal anxiety may have sex‐specific effects on early EF and that pre‐ and postnatal stress may differently affect infant EF/cognitive development. The implications of these findings and important future directions are discussed. 相似文献
167.
David T. Kryszajtys Tara E. Hahmann Andrée Schuler Sarah Hamilton-Wright Carolyn P. Ziegler Flora I. Matheson 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(3):893-914
Despite many studies indicating an association between problem gambling and delinquent behaviours among adolescents, there has been no effort to systematically analyze the state of the literature on this relationship. To fill this gap, we conducted a scoping review of the literature published between 2000 and 2016 on problem gambling and delinquent behaviours among adolescents. We searched twelve databases and reviewed reference lists to identify eligible studies. Search terms included a combination of medical subject headings and keywords for gambling, youth, and delinquency, which were combined with the Boolean operator “AND”. 1795 studies were identified through the literature search. Nine studies were eligible for inclusion. All of the studies were conducted in North America, with primarily male participants, and most of the data were cross-sectional. No qualitative studies met the inclusion criteria. Screening tools used to measure problem gambling were inconsistent, making comparisons across studies difficult. We found a consistent moderate to strong association between problem gambling and delinquent behaviour. Only one study presented associations by socio-economic status and none considered gender, sex or ethnic differences. Studies in the review showed that problem gambling is associated with both violent and non-violent behaviours among adolescents. These associations may suggest that problem gambling and delinquent behaviours have common risk factors and reflect a syndrome of risky behaviours best targeted through prevention and treatment that is holistic and considers the context in which the youth is situated. Further research is warranted to better understand the relationship between problem gambling and delinquent behaviours. 相似文献
168.
Vladyslav Kushnir Alexandra Godinho David C. Hodgins Christian S. Hendershot John A. Cunningham 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(4):1407-1421
Most problem gamblers do not seek formal treatment, recovering on their own through cognitive re-appraisal or self-help strategies. Although barriers to treatment have been extensively studied, there is a paucity of research on self-directed changes in problem gambling and very few studies have examined these changes prospectively. The aim of this study was to examine the trajectory of gambling severity and behavior change over an 18-month period, among a sample of non-treatment seeking/attending problem gamblers recruited from the community (N?=?204) interested in quitting or reducing gambling. Separate mixed effects models revealed that in absence of formal treatment, significant reductions in gambling severity, frequency, and amount gambled could be observed over the course of a 6 to 9-month period and that changes experienced within the first 12 months were maintained for an extended 6 months. Problem gambling severity at baseline was significantly associated with changes in severity over time, such that participants with more severe gambling problems demonstrated greater reductions in their gambling severity over time. A total of 11.1% of participants gambled within a low-risk threshold at 18 months, although 28.7% of the sample reported consecutive gambling severity scores below problem levels for the duration of 1 year or longer. The findings suggest that among problem gamblers motivated to quit or reduce their gambling, significant self-directed changes in gambling severity can occur over a relatively short time. Additional prospective studies are needed to document the role of specific self-help tools or thought processes in exacting gambling changes. 相似文献
169.
David Lévesque Serge Sévigny Isabelle Giroux Christian Jacques 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(3):807-822
Despite numerous studies demonstrating the influence of cognitive distortions on gambling problem severity, empirical data regarding the role of psychological vulnerability on the latter is limited. Hence, this study assesses the mediating effect of cognitive distortions between psychological vulnerability (personality and mood), and gambling problem severity. It also verifies whether the relationships between these variables differs according to the preferred gambling activity. The sample is composed of 272 male gamblers [191 poker players; 81 video lottery terminal (VLT) players] aged between 18 and 82 years (M = 35.2). Bootstrap analysis results revealed that cognitive distortions mediate the effect of narcissism on gambling problem severity for both groups. The level of depression for VLT players significantly predicted gambling problem severity, both directly and indirectly via the mediating effect of cognitive distortions. Mediation analyses also indicated that narcissism had an indirect impact on problem gambling through cognitive distortions for both groups. These findings suggest that certain vulnerabilities related to personality and mood may influence cognitive distortion intensity and gambling problem severity. In addition, psychological vulnerabilities could differ based on preferred gambling activity. These results may be useful for prevention policies, identifying high risk gamblers and planning psychological interventions. 相似文献
170.
David Forrest O. David Gulley 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(1):39-53
The UK Lotto game was introduced in November 1994 with a standard 6/49 format and an entry fee of £1 per ticket. After several years, revenue began to fall despite extensive publicity and a variety of inducements. By 2013, nominal weekly revenue was less than half the 1995 level. In October 2013, the operator doubled the price of a ticket to £2 and made a number of changes to the pay-out structure of smaller prizes. The intent of the changes was to reverse the long downward trend in game revenue by encouraging higher jackpots and offering more pay-out opportunities for each ticket. We use draw by draw revenue and other data to evaluate how players responded to these changes and find that, while ticket sales fell dramatically, total revenue rose following the changes. Primarily this appears to have been the consequence of increased frequency of rollovers (and therefore of more frequent high jackpot draws) rather than ticket price inelasticity. However, although there was a short-term gain in revenue, the changes did not arrest, and indeed seem to have accentuated, the long-run trend decrease in the revenue generated by the game. 相似文献