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31.
“Cruising” infants can only walk using external support to augment their balance. We examined cruisers' understanding of support for upright locomotion under four conditions: cruising over a wooden handrail at chest height, a large gap in the handrail, a wobbly unstable handrail, and an ill‐positioned low handrail. Infants distinguished among the support properties of the handrails with differential attempts to cruise and handrail‐specific forms of haptic exploration and gait modifications. They consistently attempted the wood handrail, rarely attempted the gap, and occasionally attempted the low and wobbly handrails. On the wood and gap handrails, attempt rates matched the probability of cruising successfully, but on the low and wobbly handrails, attempt rates under‐ and overestimated the probability of success, respectively. Haptic exploration was most frequent and varied on the wobbly handrail, and gait modifications—including previously undocumented “knee cruising”—were most frequent and effective on the low handrail. Results are discussed in terms of developmental changes in the meaning of support.  相似文献   
32.
Barbara Brenner, JD, was the Executive Director of Breast Cancer Action (BCA) from 1995–2010. Before that, she was a longtime activist in the anti-war movement and an attorney who, for most of her career, practiced public policy law. After she was diagnosed with breast cancer in 1993 at the age of 41, she took the helm of BCA. Under her leadership, the organization moved into a position of national advocacy—demanding research on the causes and prevention of breast cancer, including the role of industrial pollutants. Barbara started the “Think Before You Pink” campaign, encouraging people to question whether companies that display pink ribbons actually produce products that harm women's health or generate any funds to fight breast cancer. Her blog, “Healthy Barbs,” challenged readers to critique routine healthcare practices and policies. Barbara received numerous awards, including a Jefferson Award for Public Service in 2007, the Smith College Medal in 2012, and the ACLU-Northern California's Lola Hanzel Courageous Advocacy Award in 2012. Barbara had a recurrence of breast cancer in 1996. She died of complications associated with amyotrophic lateral sclerosis, ALS, on May 10, 2013.  相似文献   
33.
Parenting is a critical factor in substance abuse prevention. Positive parenting behaviors are identified as a protective factor for substance abuse among youth. Limited research exists that investigates the role of parenting practices on minority youth substance use. The present study seeks to examine correlates between parenting and recent alcohol use among African American youth. Specifically, to what extent do African American students report experiencing specific parenting behaviors that are measured by the National Household Survey on Drug Use and Health?, do specific parenting behaviors increase the risk of recent alcohol use among African American youth?, does the impact of parenting behaviors on recent alcohol use among African American youth differ based on sex (males and females) and age category (12–13, 14–15, and 16–17 years old) were examined in this study? Logistic regression analysis of the National Household Survey on Drug Use and Health was conducted to examine the research questions. Findings indicated that parenting behaviors was associated with recent alcohol among youth. Significant differences were found for males, females, 12–13, 14–15, and 16–17 years olds. Study findings demonstrate the importance of positive parenting behaviors in youth alcohol prevention. Program specialists may target parenting as a means of preventing and reducing youth alcohol use among African American youth.  相似文献   
34.
This exploratory study aimed to examine which components of early childhood conscience predicted bullying involvement around school entry. In the population‐based Generation R Study, teacher reports of bullying involvement and parent reports of conscience were available for 3,244 children (M age = 6.7 years). Higher levels of overall conscience predicted lower bullying perpetration scores, independently of intelligence quotient, temperamental traits and sociodemographic characteristics. Particularly, the subscales guilt, confession, and internalized conduct, and to a lesser extent empathy, predicted bullying perpetration. Conscience was not related to victimization. Similar results were found using observations during so‐called ‘cheating games’ (subsample N = 450 children). Findings suggest that improving children's understanding of moral standards and norms may be a potential target for bullying intervention programs in early primary school.  相似文献   
35.
The memory of combat experience endures in World War II veterans. As veterans age, traumatic memory that previously may have been suppressed in the busyness of family and everyday life can re-emerge. Combat stress may affect not only the veterans, but also those people closely associated with them. Interviews were conducted with World War II veteran aircrew, wives, children, grandchildren, siblings, and friends to examine the impact of combat experience on the veterans and the family across the life course from the perspectives of the various participants. The combat experience significantly affected the life course of most.  相似文献   
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Are there times when durable spending is less responsive to economic stimulus? We argue that aggregate durable expenditures respond more sluggishly to economic shocks during recessions because microeconomic frictions lead to declines in the frequency of households' durable adjustment. We show this by first using indirect inference to estimate a heterogeneous agent incomplete markets model with fixed costs of durable adjustment to match consumption dynamics in PSID microdata. We then show that aggregating this model delivers an extremely procyclical Impulse Response Function (IRF) of durable spending to aggregate shocks. For example, the response of durable spending to an income shock in 1999 is estimated to be almost twice as large as if it occurred in 2009. This procyclical IRF holds in response to standard business cycle shocks as well as in response to various policy shocks, and it is robust to general equilibrium. After estimating this robust theoretical implication of micro frictions, we provide additional direct empirical evidence for its importance using both cross‐sectional and time‐series data.  相似文献   
39.
This article considers in-sample prediction and out-of-sample forecasting in regressions with many exogenous predictors. We consider four dimension-reduction devices: principal components, ridge, Landweber Fridman, and partial least squares. We derive rates of convergence for two representative models: an ill-posed model and an approximate factor model. The theory is developed for a large cross-section and a large time-series. As all these methods depend on a tuning parameter to be selected, we also propose data-driven selection methods based on cross-validation and establish their optimality. Monte Carlo simulations and an empirical application to forecasting inflation and output growth in the U.S. show that data-reduction methods outperform conventional methods in several relevant settings, and might effectively guard against instabilities in predictors’ forecasting ability.  相似文献   
40.
A Markov-chain faculty planning model to be used with institution-specific data is presented to describe and better understand the complex phenomena of faculty movement through an institution and on its relationship to salary costs, composition of the faculty, and faculty turnover rate. The model updates the earlier work done at Stanford University and Oregon State University by the addition of states for fixed-term appointments and for part-time FTEs to reflect accurately the current hiring trends at many institutions. The model is implemented and tested at two different institutions. The findings suggest that the model is a viable means of gaining useful insights and quantitative data on the faculty profile, salary costs, expected departures, and part-time trends. And further, when used as a planning tool, and the model apparently is comprehensive and flexible enough to analyze the probable effects, both in the short and long run, of alternative personnel policies on the faculty composition.  相似文献   
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