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1.
Researchers have theorized that programs to promote positive citizenship should begin with an opportunity for adolescents to participate in civic activities, such as community service or political volunteering. In this article we extend the theory by arguing that a more systemic approach is needed, in which a civic context is developed to promote citizenship. We hypothesize that living within a consistent civic context leads to civic engagement in late adolescence and into young adulthood. We use a diverse, longitudinal dataset to test this hypothesis. We find that social interactions with peers, parent modeling of civic behaviors, and cultural factors, such as ethnicity-specific practices, cumulatively result in a higher level of civic activities among youth and that a continued context that includes these factors results in a higher level of civic activities into adulthood. The implications of our findings are discussed with regard to program and policy development.  相似文献   

2.
The complex interplay between genes and environment affecting body mass gain over lifecycle periods of risk is not well understood. We use longitudinal sibling cohort data to examine the role of shared household environment, additive genetic, and shared genetic effects on BMI and BMI change. In the National Longitudinal Study of Adolescent Health, siblings and twin pairs sharing households for ≥10 years as adolescents (N = 5,524; mean = 16.5 ± 1.7 years) were followed into young adulthood (N = 4,368; mean = 22.4 ± 1.8 years). Using a variance component approach, we quantified genetic and household effects on BMI in siblings and nonsiblings sharing household environments over time. Adjusting for race, age, sex, and age‐by‐sex interaction, we detected a heritability of 0.43 ± 0.05 for BMI change. Significant household effects were noted during the young adulthood period only (0.11 ± 0.06). We find evidence for shared genetic effects between BMI and BMI change during adolescence (genetic correlation (ρG) = 0.61 ± 0.03) and young adulthood (ρG = 0.23 ± 0.06). Our findings support a complex etiology of BMI and BMI change.  相似文献   

3.
4.
This study examined weight status during adolescence and young adulthood, and young adult health condition diagnosis. Data are from 10,439 African‐American, Hispanic, and white men and women participating in the National Longitudinal Study of Adolescent Health during Waves 1 (adolescence: ages 12–19) and 3 (young adulthood: ages 19–26). Categories were created differentiating individuals based on their weight status during adolescence and young adulthood: (i) obese during adolescence and young adulthood (i.e., continuously obese), (ii) obese during adolescence only, (iii) obese during young adulthood only, and (iv) never obese. Multilevel random intercept regression models were used to examine the impact of obesity category, sex, and race/ethnicity on young adult asthma, diabetes, high cholesterol, and high blood pressure. Continuous obesity increased the likelihood for young adult disease and health risk conditions compared to individuals who were never obese. Obesity isolated to adolescence (Wave 1) increased the likelihood for high cholesterol and high blood pressure, whereas obesity isolated to young adulthood (Wave 3) also increased the likelihood for diabetes—all increases were relative to nonobese weight status during both periods. Associations varied in direction and degree when sex and race/ethnicity were considered. Findings clarify some of the mixed understandings regarding the associations between age of onset and stability of obesity, and health outcomes with important public health implications. Although results indicate obesity isolated to a single developmental period does have health repercussions, obesity experienced continuously during adolescence and young adulthood greatly intensified risk across all health conditions.  相似文献   

5.
Objective: The stability of several indicators of body composition and adipose tissue distribution over 12 years was quantified. Research Methods and Procedures: The participants were 77 boys and 76 girls who were evaluated along with their parents at baseline as children and adolescents (8 to 18 years of age) and remeasured as young adults 12 years later. Indicators of body composition included the body mass index, fat mass, fat free mass, percentage of body fat, sum of six skinfolds (SF6), and the first principal component of six age‐adjusted skinfold residuals. Relative adipose tissue distribution was represented by the second principal component of skinfold residuals and a trunk‐to‐extremity skinfold ratio, adjusted for SF6. Results: Partial interage correlations, controlling for initial age and length of follow‐up, were 0.65 and 0.59 for the body mass index, 0.59 and 0.64 for fat mass, 0.65 and 0.57 for fat free mass, 0.50 and 0.57 for percentage of body fat, 0.66 and 0.44 for SF6, 0.64 and 0.42 for the first principal component of six age‐adjusted skinfold residuals, 0.19 and 0.31 for the second principal component of skinfold residuals, and 0.41 and 0.47 for trunk‐to‐extremity skinfold ratio, adjusted for SF6, in men and women, respectively. Multiple regression analyses indicated that the significant partial R2 values of parental measurements on the prediction of their offspring in young adulthood ranged from 2% to 9%. Discussion: The results indicate moderately high stability of indicators of body composition and somewhat lower stability of measures of adipose tissue distribution. Overall, parental measures offer less predictive value than do measures of childhood and adolescent body composition and adipose tissue distribution.  相似文献   

6.

Background

To know how moderate-to-vigorous physical activity (MVPA) and sedentary time change across lifespan periods is needed for designing successful lifestyle interventions. We aimed to study changes in objectively measured (accelerometry) MVPA and sedentary time from childhood to adolescence and from adolescence to young adulthood.

Methods

Estonian and Swedish participants from the European Youth Heart Study aged 9 and 15 years at baseline (N = 2312) were asked to participate in a second examination 6 (Sweden) to 9/10 (Estonia) years later. 1800 participants with valid accelerometer data were analyzed.

Results

MVPA decreased from childhood to adolescence (−1 to −2.5 min/d per year of follow-up, P = 0.01 and <0.001, for girls and boys respectively) and also from adolescence to young adulthood (−0.8 to −2.2 min/d per year, P = 0.02 and <0.001 for girls and boys, respectively). Sedentary time increased from childhood to adolescence (+15 and +20 min/d per year, for girls and boys respectively, P<0.001), with no substantial change from adolescence to young adulthood. Changes in both MVPA and sedentary time were greater in Swedish than in Estonian participants and in boys than in girls. The magnitude of the change observed in sedentary time was 3–6 time larger than the change observed in MVPA.

Conclusions

The decline in MVPA (overall change = 30 min/d) and increase sedentary time (overall change = 2∶45 h/d) observed from childhood to adolescence are of concern and might increase the risk of developing obesity and other chronic diseases later in life. These findings substantially contribute to understand how key health-related behaviors (physical activity and sedentary) change across important periods of life.  相似文献   

7.
To discover the laws of development of subjective experience, we must study the relationships between affective and intellectual processes in that experience (Vygotsky, 1981). Changes in this relationship and the formation of new interfunctional interactions during the course of emotional development shape the dynamic of such experiences and give rise to qualitatively new types.  相似文献   

8.

Introduction

Obesity-susceptibility loci have been related to adiposity traits in adults and may affect body fat estimates in adolescence. There are indications that different sets of obesity-susceptibility loci influence level of and change in obesity-related traits from adolescence to adulthood.

Objectives

To investigate whether previously reported obesity-susceptible loci in adults influence adiposity traits in adolescence and change in BMI and waist circumference (WC) from adolescence into young adulthood. We also examined whether physical activity modifies the effects of these genetic loci on adiposity-related traits.

Methods

Nine obesity-susceptibility variants were genotyped in 1 643 adolescents (13–19 years old) from the HUNT study, Norway, who were followed-up into young adulthood. Lifestyle was assessed using questionnaires and anthropometric measurements were taken. The effects of genetic variants individually and combined in a genetic predisposition score (GPS) on obesity-related traits were studied cross-sectionally and longitudinally. A modifying effect of physical activity was tested.

Results

The GPS was significantly associated to BMI (B: 0.046 SD/allele [0.020, 0.073], p = 0.001) in adolescence and in young adulthood (B: 0.041 SD/allele [0.015, 0.067], p = 0.002) as it was to waist circumference (WC). The GPS was not associated to change in BMI (p = 0.762) or WC (p = 0.726). We found no significant interaction effect between the GPS and physical activity.

Conclusions

Our observations suggest that obesity-susceptibility loci established in adults affect BMI and WC already in adolescence. However, an association with change in adiposity-related traits from adolescence to adulthood could not be verified for these loci. Neither could an attenuating effect of physical activity on the association between the obesity-susceptibility genes and body fat estimates be revealed.  相似文献   

9.
10.
Exposure to chronic stress during adolescence can shape behaviour, cognition and physiology in adulthood, but the consequences of these long‐term changes remain unclear. Prior studies reporting altered performance following exposure to stress in adolescence have generally interpreted lasting changes as impairments. However, we have recently shown that exposure to chronic unpredictable stress during adolescence (from post‐natal days 30–70) can enhance performance in a context‐dependent manner during a foraging task. Increases in foraging performance, (previously measured by the number of rewards obtained), are often associated with trade‐offs in other behaviours, such as vigilance. Here, we examined the effect of stress exposure in adolescence on adult foraging in male Sprague Dawley rats to determine (1) whether the increase in foraging performance exhibited by animals exposed to stress in adolescence is balanced by a decrease in vigilance, and (2) whether stress in adolescence alters time allocation between foraging and vigilance behaviours in low‐ and high‐threat conditions. We found no evidence of a trade‐off between foraging and vigilance; under low‐threat conditions, rats exposed to stress in adolescence spent more time being vigilant compared with unstressed rats, suggesting that exposure to stress in adolescence enhances anticipation of threat in adulthood. Under high‐threat conditions, adolescent‐stressed and unstressed rats did not differ in foraging and vigilance behaviours. Given that we have previously found that rats exposed to stress in adolescence nearly double food intake under high‐threat, and we now show that high‐performing rats do not spend more time foraging, it appears that stress exposure in adolescence may enhance foraging efficiency (food consumed/time) under high‐threat conditions rather than time allocation between foraging and competing behaviours. We also examined the relationship, at the level of the individual, between foraging performance and foraging and vigilance behaviours. We found that changes in individual foraging performance between low‐ and high‐threat conditions were independent of behavioural changes (i.e. both highly and poorly performing rats were equally active and contacted a similar number of patches). This suggests that the ability to obtain many rewards under high‐threat conditions may be related to efficiency, rather than the frequency of foraging and effort‐related behaviours.  相似文献   

11.
12.

Background

Prenatal life exposures, potentially manifested as altered birth size, may influence the later risk of major chronic diseases through direct biologic effects on disease processes, but also by modifying adult behaviors such as physical activity that may influence later disease risk.

Methods/Principal Findings

We investigated the association between birth weight and leisure time physical activity (LTPA) in 43,482 adolescents and adults from 13 Nordic cohorts. Random effects meta-analyses were performed on categorical estimates from cohort-, age-, sex- and birth weight specific analyses. Birth weight showed a reverse U-shaped association with later LTPA; within the range of normal weight the association was negligible but weights below and above this range were associated with a lower probability of undertaking LTPA. Compared with the reference category (3.26–3.75 kg), the birth weight categories of 1.26–1.75, 1.76–2.25, 2.26–2.75, and 4.76–5.25 kg, had odds ratios of 0.67 (95% confidence interval: 0.47, 0.94), 0.72 (0.59, 0.88), 0.89 (0.79, 0.99), and 0.65 (0.50, 0.86), respectively. The shape and strength of the birth weight-LTPA association was virtually independent of sex, age, gestational age, educational level, concurrent body mass index, and smoking.

Conclusions/Significance

The association between birth weight and undertaking LTPA is very weak within the normal birth weight range, but both low and high birth weights are associated with a lower probability of undertaking LTPA, which hence may be a mediator between prenatal influences and later disease risk.  相似文献   

13.

Objective

Prospective associations between obesity in adolescence and adult socioeconomic outcomes, and potential mediators, were examined in a contemporary cohort.

Methods

Longitudinal data collected in 1998 to 1999 (Project EAT‐I) and 2015 to 2016 (EAT‐IV) were analyzed for 1,796 participants who provided data at both time points. Adolescents (mean age = 14.8 years) self‐reported demographic and psychosocial variables (EAT‐I) and follow‐up outcomes (EAT‐IV). Body weight and height were directly measured. Bachelor's degree or more education, income ≥ US $50,000, and partnered status at follow‐up were examined by baseline obesity (>95th BMI percentile) using logistic regression. Self‐esteem, depression, and weight‐related teasing were examined as mediators using multivariate probit regressions. All analyses were adjusted for race, baseline age, and parent socioeconomic status.

Results

Girls with obesity were significantly less likely to have achieved a bachelor’s degree (OR 0.32, 95% CI [0.18, 0.58]; P < 0.001), earn ≥ $50,000 annually (OR 0.57, 95% CI [0.33, 0.99]; P < 0.04), or be partnered (OR 0.45, 95% CI [0.27, 0.75]; P < 0.002) in adulthood. No associations were observed among boys. Among girls, depression mediated 8.5% and 23.6% of the association between adolescent obesity and adult education and income, respectively.

Conclusions

Adolescent girls with obesity have lower educational attainment and income and are less likely to be partnered in later adulthood. Depression may partly mediate the associations.
  相似文献   

14.
《应用发育科学》2013,17(2):67-85
A theoretical framework about protective factors (models protection, controls protection, support protection) and risk factors (models risk, opportunity risk, vulnerability risk) was employed to articulate the content of 4 key contexts of adolescent life—family, peers, school, and neighborhood—in a cross-national study of problem behavior among 7th-, 8th-, and 9th-grade adolescents in the United States (n = 1,596) and the People's Republic of China (n = 1,739). Results were very similar in both samples and across genders. Measures of protection and risk in each of the 4 contexts uniquely contributed to the account of problem behavior involvement even when individual-level measures of protection and risk were controlled. Context protection was also shown to moderate individual-level risk and protection in 1 context moderated risk within that context and in other contexts. Controls protection—protection provided by rules, regulations, and expected sanctions for transgression from adults and peers—was the most important measure of context protection in all but 1 context. The family and peer contexts were the most influential in the U.S. sample, and the peer and school contexts were the most influential in the Chinese sample; the neighborhood context was least influential in both samples.  相似文献   

15.
16.
As representatives of organisms with complex life histories, frogs provide an ideal system to study predator‐induced carryover effects: how the risk of predation in one life stage can impact predator–prey interactions in a later stage. Invertebrate predation on frogs has been widely reported, although studies of the behavioral mechanisms underlying their interactions in the terrestrial stage have been lacking. We made detailed observations of interactions between a wolf spider (Tigrosa helluo) and Blanchard's cricket frog (Acris blanchardi) to determine factors that predict capture success and to evaluate potential carryover effects from aquatic predation risk. Juvenile frogs, reared with or without dragonfly predator cues, were placed in an arena with or without spider cues and allowed to interact with a spider. Spiders captured frogs, and an interaction between frog size and activity predicted frog survival. We found no evidence that either aquatic or terrestrial cues altered frog behavior or survival. By preying upon a demographically important life stage, spiders may contribute to population dynamics in frogs.  相似文献   

17.

Background

Common negative events can precipitate the onset of internalizing symptoms. We studied whether their occurrence in childhood is associated with mental health trajectories over the course of development.

Methods

Using data from the TEMPO study, a French community-based cohort study of youths, we studied the association between negative events in 1991 (when participants were aged 4–16 years) and internalizing symptoms, assessed by the ASEBA family of instruments in 1991, 1999, and 2009 (n = 1503). Participants'' trajectories of internalizing symptoms were estimated with semi-parametric regression methods (PROC TRAJ). Data were analyzed using multinomial regression models controlled for participants'' sex, age, parental family status, socio-economic position, and parental history of depression.

Results

Negative childhood events were associated with an increased likelihood of concurrent internalizing symptoms which sometimes persisted into adulthood (multivariate ORs associated with > = 3 negative events respectively: high and decreasing internalizing symptoms: 5.54, 95% CI: 3.20–9.58; persistently high internalizing symptoms: 8.94, 95% CI: 2.82–28.31). Specific negative events most strongly associated with youths'' persistent internalizing symptoms included: school difficulties (multivariate OR: 5.31, 95% CI: 2.24–12.59), parental stress (multivariate OR: 4.69, 95% CI: 2.02–10.87), serious illness/health problems (multivariate OR: 4.13, 95% CI: 1.76–9.70), and social isolation (multivariate OR: 2.24, 95% CI: 1.00–5.08).

Conclusions

Common negative events can contribute to the onset of children''s lasting psychological difficulties.  相似文献   

18.
19.
In general, support by social allies may reduce stress, increase an individual's status and facilitate access to resources. In Greylag geese (Anser anser), offspring stay with their parents for an entire year or even longer and thereby enjoy social support in encounters with other flock members. We investigated the influence of spatial distance to one's allies on the outcome of agonistic encounters in a natural flock situation for a total of 12 sibling groups after fledging. In addition, we tested two groups of hand‐raised juvenile geese over a time span of 11/2 yr. Passive (i.e. not interfering) human supporters of different familiarity were placed at a standard distance during food provisionings, which produced a tight flock situation. Success in agonistic interactions increased with decreasing distance to members of their social unit. The hand‐raised juveniles were more successful in agonistic interactions and showed increased feeding rates when accompanied by a familiar human than when alone or with a non‐familiar human. The effect of the presence of familiar humans on success in agonistic encounters significantly decreased with increasing age, while feeding rates remained elevated. The positive effects of social support were particularly evident in females. We conclude that social support has similar effects and functions in the highly social greylag geese as reported for social mammals.  相似文献   

20.
IntroductionPrior studies examining longitudinal patterns of television (TV) watching have tended to use analytical approaches which do not allow for heterogeneity in the variation of TV watching over time. In the current study, we used latent class analysis (LCA) to examine the relationships between television watching (from childhood to early adulthood) and body fat percentage (%) and mental health.MethodsData were collected from 2411 participants (50% female) from the Raine Study, a prospective birth cohort study in Australia. Participants were followed up over 15 years and answered questions about hours of TV watching per week at six time-points (5, 8, 10, 14, 17 and 20yrs). Trajectories of television watching were estimated using LCA and appropriate regression models used to test the association of television watching class with percentage body fat (measured by DXA) and mental health (DASS-21) at age 20. Physical activity was used as a covariate.ResultsThree distinct trajectories of TV watching were identified. Class 1 (47.4%) had consistently high (>14 hrs/wk) levels of TV watching, Class 2 (37.9%) was characterised by an increase in TV watching over adolescence and Class 3 (14.7%) had consistently lower (<14 hrs/wk) TV watching over 15 years. Sex was used as an active covariate in the latent class model and was significantly associated with class membership (p<0.001), with females comprising 45%, 47% and 59% of Class 1, 2 and 3 respectively. In females, membership in Class 2 or 3 was associated with lower body fat % at age 20, compared to Class 1 (p<0.001). For males, membership in Class 2 was associated with lower body fat % compared with males in Class 1 (p = 0.026). Membership of TV watching class and mental health were not related (p>0.05).ConclusionsTV watching from childhood to young adulthood appears to be a relatively stable behavior for around two thirds of participants, but not everyone tracks consistently. This study identified a subset of participants with low levels of TV watching in childhood and also that this group, despite an increase in TV watching over adolescence, maintained a lower level of body fat in young adulthood.  相似文献   

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