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101.
Objectives. Using data from the National Longitudinal Study of Adolescent Health (Add Health), we investigate whether Asian and Latino youth value racial boundaries more than ethnic boundaries. We evaluate the relative preferences of same‐ethnic, same‐race (but different‐ethnic), and different‐race friends. Methods. We use multilevel multinomial logistic regression models to examine the odds of choosing same‐ethnic, different‐ethnic (but same‐race), and different‐race friends net of the opportunity to interact. Results. We find strong effects of school racial and ethnic composition, immigrant status, and parental education on the likelihood of crossing boundaries in the selection of friends. In addition, we develop a new scale of panethnicity and find substantial ethnic group variation in panethnic sentiment. Conclusion. We find an overwhelming preference for same‐ethnic peers over same‐race (different‐ethnic) and different‐race peers.  相似文献   
102.
Newborn infants preferentially orient to familiar over unfamiliar speech sounds. They are also better at remembering unfamiliar speech sounds for short periods of time if learning and retention occur after a feed than before. It is unknown whether short‐term memory for speech is enhanced when the sound is familiar (versus unfamiliar) and, if so, whether the effect is further enhanced by feeding. We used a two‐factorial design and randomized infants to one of four groups: prefeed‐unfamiliar, prefeed‐familiar, postfeed‐unfamiliar, and postfeed‐familiar. Memory for either familiar or unfamiliar speech (the infant's mother saying “baby” versus a female stranger saying “beagle”) was assessed using head turning to sound in an habituation–recovery paradigm and a retention delay of 85 sec either before or after a typical milk feed. Memory for the familiar speech–voice was enhanced relative to the unfamiliar speech–voice, expressed by significantly less head turning toward the habituated sound stimulus when it was re‐presented after the delay. Memory for familiar or unfamiliar speech was not significantly enhanced from pre‐ to postfeeding, nor was there a significant interaction. This is the first demonstration in newborns that familiarity enhances short‐term memory for speech–voice sound.  相似文献   
103.
Abstract

At a time of significant restructuring in the community services labour market, it is particularly pertinent to analyse the current labour market opportunities available to new social work graduates. In 1995, using a small RMIT-funded (Royal Melbourne Institute of Technology) research grant, five schools of social work in Victoria collaborated to pilot a survey of the employment paths of the previous year's social work graduates. The survey was repeated in 1996. A complementary project which analysed the job advertisements for social work and social work-related positions during six months in both 1995 and 1996 provided further insight into the employment opportunities being advertised. Survey results showed a high rate of employment among new graduates with a decreasing number of graduates being employed in designated “social work” positions. This trend was reflected in the requirements for the positions advertised. The implications of this diversity of jobs and the decrease in designated “social work” positions are discussed, particularly in terms of broader changes in the world of work.  相似文献   
104.
ABSTRACT

Objective: Mindfulness-based interventions have been shown to have psychological benefits in college students. We explored the effects of an academic Seminar on Compassion on student psychological health. Participants: Forty-one participants (14 male, 27 female, mean age 19.8 ± 1.4 years) were assessed pre- and post- spring semesters 2013 and 2014. Methods: Students were randomized to the Seminar on Compassion or a wait-list control group. Participants completed self-report measures on anxiety, depression, perceived stress, self-compassion, compassion and mindfulness. Salivary alpha-amylase was also assessed. Results: At baseline, self-compassion and mindfulness were negatively correlated with depression, anxiety, and perceived stress. There were significant changes between the intervention and control group from Time 1 to Time 2 in mindfulness, self-compassion, compassion, and salivary alpha-amylase; however, there were no significant changes in depression, anxiety, and perceived stress. Conclusions: The course was effective in increasing mindfulness, self-compassion and compassion, and decreasing a salivary marker of stress.  相似文献   
105.
Abstract

Objective: Caffeine and dietary supplement (DS) use by college students is not well-documented. Given reported associations between energy drink consumption and sensation seeking, we used the Sensation Seeking Scale Form V (SSS-V) to assess relationships between sensation-seeking, caffeine, and DS use. Participants: Data from 1,248 college students from five US institutions were collected from 2009 to 2011. Methods: Linear regression was used to examine relationships between scores on the SSS-V and caffeine and DS use, demographic, and lifestyle characteristics. Results: Male sex, nonHispanic race-ethnicity, higher family income, tobacco use, consuming caffeinated beverages, more than 400?mg caffeine per day, and energy drinks with alcohol at least 50% of the time, were significantly associated with higher total SSS-V scores (P?<?0.001). Those using protein DSs had higher total, disinhibition, and boredom susceptibility SSS-V scores (Ps?<?0.001). Conclusions: Results demonstrate a positive correlation between sensation-seeking attitudes and habitual caffeine, energy drink, and DS consumption.  相似文献   
106.
Covariate measurement error occurs commonly in survival analysis. Under the proportional hazards model, measurement error effects have been well studied, and various inference methods have been developed to correct for error effects under such a model. In contrast, error-contaminated survival data under the additive hazards model have received relatively less attention. In this paper, we investigate this problem by exploring measurement error effects on parameter estimation and the change of the hazard function. New insights of measurement error effects are revealed, as opposed to well-documented results for the Cox proportional hazards model. We propose a class of bias correction estimators that embraces certain existing estimators as special cases. In addition, we exploit the regression calibration method to reduce measurement error effects. Theoretical results for the developed methods are established, and numerical assessments are conducted to illustrate the finite sample performance of our methods.  相似文献   
107.
Recurrent event data arise commonly in medical and public health studies. The analysis of such data has received extensive research attention and various methods have been developed in the literature. Depending on the focus of scientific interest, the methods may be broadly classified as intensity‐based counting process methods, mean function‐based estimating equation methods, and the analysis of times to events or times between events. These methods and models cover a wide variety of practical applications. However, there is a critical assumption underlying those methods–variables need to be correctly measured. Unfortunately, this assumption is frequently violated in practice. It is quite common that some covariates are subject to measurement error. It is well known that covariate measurement error can substantially distort inference results if it is not properly taken into account. In the literature, there has been extensive research concerning measurement error problems in various settings. However, with recurrent events, there is little discussion on this topic. It is the objective of this paper to address this important issue. In this paper, we develop inferential methods which account for measurement error in covariates for models with multiplicative intensity functions or rate functions. Both likelihood‐based inference and robust inference based on estimating equations are discussed. The Canadian Journal of Statistics 40: 530–549; 2012 © 2012 Statistical Society of Canada  相似文献   
108.
Adolescent relational violence has significant and pervasive impacts for young people's current and future relationships. It is known that there is a cross-over between adolescent family violence and other offending behaviour, meaning there is a need for youth justice systems to recognise and respond to these forms of violence. This paper outlines a pilot intervention, the KIND Program, run in Youth Justice South Australia, and aimed at intervening with adolescent family and dating violence. KIND aims to provide tailored systemic intervention to young people and their support network, reducing violence while increasing connection and strength within relationships. The pilot of KIND ran for seven months in 2017, and had eight families participating in the program. Participation in, feedback from, and impact of the program suggest that participation was worthwhile and useful for young people and their families. The KIND Program would benefit from a more extensive pilot period to explore the outcomes of this form of intervention.  相似文献   
109.
In this article we examine the relationship between extent of gambling for U.S. adults and the distance from their residence to the nearest casino or track. We employ data from a telephone survey of U.S. adults conducted in 2011–2013. The chances that the respondents gambled in the past year, were frequent gamblers, or were problem gamblers were greater if they lived close to a casino. The chances that the respondents gambled in the past year or were frequent gamblers were greater if they lived close to a horse or dog track. The effects of closeness to a casino on the likelihood of past-year gambling, frequent gambling, and problem gambling, as well as the effect of closeness to a track on past-year gambling, extended to about 30 miles from the respondent’s home. In addition, the concentration of casinos within 30 miles of the respondent’s home was positively related to the respondents’ chance of being a frequent or problem gambler. If a respondent had no casinos within 30 miles, he or she had a 2.7 % chance of being a problem gambler; if one casino, a 3.9 % chance; if six or more, a 6.2 % chance. The authors estimate that at least part of this effect is causal.  相似文献   
110.
Urbanization is becoming increasingly important in terms of climate change and ecosystem functionality worldwide. We are only beginning to understand how the processes of urbanization influence ecosystem dynamics and how peri-urban environments contribute to climate change. Brisbane in South East Queensland (SEQ) currently has the most extensive urban sprawl of all Australian cities. This leads to substantial land use changes in urban and peri-urban environments and the subsequent gaseous emissions from soils are to date neglected for IPCC climate change estimations. This research examines how land use change effects methane (CH4) and nitrous oxide (N2O) fluxes from peri-urban soils and consequently influences the Global Warming Potential (GWP) of rural ecosystems in agricultural use undergoing urbanization. Therefore, manual and fully automated static chamber measurements determined soil gas fluxes over a full year and an intensive sampling campaign of 80 days after land use change. Turf grass, as the major peri-urban land cover, increased the GWP by 415 kg CO2-e ha?1 over the first 80 days after conversion from a well-established pasture. This results principally from increased daily average N2O emissions of 0.5 g N2O ha?1 d?1 from the pasture to 18.3 g N2O ha?1 d?1 from the turf grass due to fertilizer application during conversion. Compared to the native dry sclerophyll eucalypt forest, turf grass establishment increases the GWP by another 30 kg CO2-e ha?1. The results presented in this study clearly indicate the substantial impact of urbanization on soil-atmosphere gas exchange in form of non-CO2 greenhouse gas emissions particularly after turf grass establishment.  相似文献   
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