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991.
This report on practice discusses the pertinence of agile principles on the basis of the case “Universitätskolleg”, a central organisational unit of Universität Hamburg to promote the quality of studies and teaching. It describes previous experience with the framework scrum and the method Lean Kanban in mind. Odds and challenges of agile principles in university context are described and reflected and next steps are named. 相似文献
992.
993.
In this paper, we introduce classical and Bayesian approaches for the Basu–Dhar bivariate geometric distribution in the presence of covariates and censored data. This distribution is considered for the analysis of bivariate lifetime as an alternative to some existing bivariate lifetime distributions assuming continuous lifetimes as the Block and Basu or Marshall and Olkin bivariate distributions. Maximum likelihood and Bayesian estimators are presented. Two examples are considered to illustrate the proposed methodology: an example with simulated data and an example with medical bivariate lifetime data. 相似文献
994.
Effortful Control Mediates Relations Between Children's Attachment Security and their Regard for Rules of Conduct
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J. K. Nordling Lea J. Boldt Jessica O'Bleness Grazyna Kochanska 《Social Development》2016,25(2):268-284
Although attachment security has been associated with children's rule‐compatible conduct, the mechanism through which attachment influences early regard for rules is not well established. We hypothesized that effortful control would mediate the link between security and indicators of children's emerging regard for rules (discomfort following rule violations, internalization of parents’ and experimenter's rules, few externalizing behaviors). In a longitudinal study, the Attachment Q‐Set was completed by parents, effortful control was observed, and Regard for Rules was observed and rated by parents. The proposed model fit the data well: Children's security to mothers predicted their effortful control, which in turn had a direct link to a greater Regard for Rules. Children's security with fathers did not predict effortful control. The mother‐child relationship appears particularly important for positive developmental cascades of self‐regulation and socialization. 相似文献
995.
Emotional Climate in Families Experiencing Homelessness: Associations with Child Affect and Socioemotional Adjustment in School
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This study examined associations among family‐level risks, emotional climate, and child adjustment in families experiencing homelessness. Emotional climate, an indirect aspect of emotion socialization, was indexed by parents’ expressed emotion while describing their children. Sociodemographic risk and parent internalizing distress were hypothesized to predict more negativity and less warmth in the emotional climate. Emotional climate was expected to predict observer‐rated child affect and teacher‐reported socioemotional adjustment, mediating effects of risk. Participants were 138 homeless parents (64 percent African‐American) and their four‐ to six‐year‐old children (43.5 percent male). During semi‐structured interviews, parents reported demographic risks and internalizing distress and completed a Five Minute Speech Sample about their child, later rated for warmth and negativity. Children's positive and negative affect were coded from videotapes of structured parent‐child interaction tasks. Socioemotional adjustment (externalizing behavior, peer acceptance, and prosocial behavior) was reported by teachers a few months later. Hypotheses were partially supported. Parent internalizing distress was associated with higher parent negativity, which was linked to more negative affect in children, and parent warmth was associated with children's positive affect. Neither emotional climate nor child affect predicted teacher‐reported externalizing behavior or peer acceptance, but parental negativity and male sex predicted lower prosocial behavior in the classroom. Future research directions and clinical implications are discussed. 相似文献
996.
Ayman M. Abd-Elrahman 《统计学通讯:理论与方法》2017,46(18):8865-8880
In this paper, we introduce a generalization of the Bilal distribution, where a new two-parameter distribution is presented. We show that its failure rate function can be upside-down bathtub shaped. The failure rate can also be decreasing or increasing. A comprehensive mathematical treatment of the new distribution is provided. The estimation by maximum likelihood is discussed, and a closed-form expression for Fisher’s information matrix is obtained. Asymptotic interval estimators for both of the two unknown parameters are also given. A simulation study is conducted and applications to real data sets are presented. 相似文献
997.
Before the fall of the Berlin Wall, mortality was considerably higher in the former East Germany than in West Germany. The gap narrowed rapidly after German reunification. The convergence was particularly strong for women, to the point that Eastern women aged 50–69 now have lower mortality despite lower incomes and worse overall living conditions. Prior research has shown that lower smoking rates among East German female cohorts born in the 1940s and 1950s were a major contributor to this crossover. However, after 1990, smoking behavior changed dramatically, with higher smoking intensity observed among women in the eastern part of Germany. We forecast the impact of this changing smoking behavior on East-West mortality differences and find that the higher smoking rates among younger East German cohorts will reverse their contemporary mortality advantage. Mortality forecasting methods that do not account for smoking would, perhaps misleadingly, forecast a growing mortality advantage for East German women. Experience from other countries shows that smoking can be effectively reduced by strict anti-smoking policies. Instead, East Germany is becoming an example warning of the consequences of weakening anti-smoking policies and changing behavioral norms. 相似文献
998.
Non-heterosexual young women have a higher rate of unintended pregnancy than their heterosexual peers, but their fertility behaviors are understudied. We use longitudinal data from the Relationship Dynamics and Social Life study to investigate mechanisms contributing to non-heterosexual women’s higher pregnancy risk. These data include weekly reports of relationships, sex, and contraceptive use over 30 months. We compare the relationships and fertility behaviors of three groups: exclusively heterosexual (consistent heterosexual behavior, identity, and attraction); mostly heterosexual (heterosexual identity with same-sex behavior and/or same-sex attraction); and LGBTQ (any non-heterosexual identity). We find that mostly heterosexual and LGBTQ women behave differently from exclusively heterosexual women in ways likely to elevate their risk of unintended pregnancy: more distinct partners during the study period, more sexual intercourse with men, less frequent contraceptive use, less use of a dual method (condom plus hormonal method), and more gaps in contraceptive coverage. Mostly heterosexual women resemble LGBTQ women in their contraceptive behavior but have significantly more intercourse with men, which may increase their pregnancy risk relative to both LGBTQ and exclusively heterosexual women. We conclude by considering implications for LGBTQ health and the measurement of sexual minority populations. 相似文献
999.
1000.
Acrylamide forms primarily from a reaction between reducing sugars (e.g., glucose and fructose) and an amino acid (asparagine, Asn) formed naturally in foods, including potatoes. This reaction occurs when carbohydrate‐rich foods are heated at temperatures above 120 °C. Multiple potato varieties were transformed with potato genomic DNA that results in down‐regulation of the expression of the asparagine synthetase‐1 gene (Asn1), significantly reducing synthesis of free Asn, and consequently lowering the potential to form acrylamide during cooking. These potatoes with low acrylamide potential (LAP) were tested in agronomic trials, and processed into French fries and potato chips. Decreased levels of acrylamide were measured in these cooked food products when derived from LAP potatoes compared with those derived from conventional potatoes. These reductions can be directly attributed to reduction in Asn levels in the LAP potatoes. The corresponding average reduction in exposure to acrylamide from French fry and potato chip consumption is estimated to be 65%, which would amount to approximately a 25% reduction in overall dietary exposure. Considering that children consume nearly three times more acrylamide than adults on a per kg body weight basis, they would experience the most impact from the reduced acrylamide associated with LAP potatoes. The potential public health impacts, in context of dietary acrylamide exposure reduction, are discussed in this study. 相似文献