Youth Risk Behavior Surveillance--United States, 1997. State and Local YRBSS Coordinators

Priority health-risk behaviors, which contribute to the leading causes of mortality and morbidity among youth and adults, often are established during youth, extend into adulthood, and are interrelated. The Youth Risk Behavior Surveillance System (YRBSS) monitors six categories of priority health-risk behaviors among youth and young adults--behaviors that contribute to unintentional and intentional injuries; tobacco use; alcohol and other drug use; sexual behaviors that contribute to unintended pregnancy and sexually transmitted diseases (STDs) (including human immunodeficiency virus [HIV] infection); unhealthy dietary behaviors; and physical inactivity. The YRBSS includes a national school-based survey conducted by the Centers for Disease Control and Prevention as well as state, territorial, and local school-based surveys conducted by education and health agencies. This report summarizes results from the national survey, 33 state surveys, 3 territorial surveys, and 17 local surveys conducted among high school students from February through May 1997. In the United States, 73% of all deaths among youth and young adults 10-24 years of age result from only four causes: motor vehicle crashes, other unintentional injuries, homicide, and suicide. Results from the national 1997 YRBSS demonstrate that many high school students engage in behaviors that increase their likelihood of death from these four causes--19.3% had rarely or never worn a seat belt; during the 30 days preceding the survey, 36.6% had ridden with a driver who had been drinking alcohol; 18.3% had carried a weapon during the 30 days preceding the survey; 50.8% had drunk alcohol during the 30 days preceding the survey; 26.2% had used marijuana during the 30 days preceding the survey; and 7.7% had attempted suicide during the 12 months preceding the survey. Substantial morbidity among school-age youth, young adults, and their children also result from unintended pregnancies and STDs, including HIV infection. YRBSS results indicate that in 1997, 48.4% of high school students had ever had sexual intercourse; 43.2% of sexually active students had not used a condom at last sexual intercourse; and 2.1% had ever injected an illegal drug. Of all deaths and substantial morbidity among adults greater than or equal to 25 years of age, 67% result from two causes--cardiovascular disease and cancer. Most of the risk behaviors associated with these causes of death are initiated during adolescence. In 1997, 36.4% of high school students had smoked cigarettes during the 30 days preceding the survey; 70.7% had not eaten five or more servings of fruits and vegetables during the day preceding the survey; and 72.6% had not attended physical education class daily. These YRBSS data are already being used by health and education officials to improve national, state, and local policies and programs to reduce risks associated with the leading causes of morbidity and mortality. YRBSS data also are being used to measure progress toward achieving 21 national health objectives and one of the eight National Education Goals.     

Competence in early adult romantic relationships: A developmental perspective on family influences.

The present prospective, longitudinal study of 193 young adults (85 men, 108 women, M?=?20.7 years old) and their partners in ongoing romantic relationships in 1997 was initiated in 1989, when the 193 target youths were in the 7th grade. On the basis of the model for the development of early adult romantic relationships (DEARR; C. Bryant & R. D. Conger, in press), the authors hypothesized that interactional processes in the family of origin would predict interpersonal skills by the target youths, which would be positively related to the early adult couple's relationship quality. Observational ratings showed that nurturant–involved parenting in the family of origin predicted behaviors by the target youth to a romantic partner that were warm, supportive, and low in hostility. These competent behaviors of the target youth were positively associated with relationship quality for the early adult couple and also mediated or explained the connection between parenting and relationship quality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adolescent psychosocial risk factors for severe intimate partner violence in young adulthood.

The authors examined prospective measures of psychosocial risk factors as predictors of severe intimate partner violence among a community sample of 610 young adults at risk for intergenerational transmission of depression. The hypothesized risk factors were youth history of depression by age 15 and maternal history of depression. Youth social functioning at age 15 was tested as a mediator of these associations. Results showed that youth history of depression by age 15 predicted victimization at age 20. Severe violence perpetration was predicted by maternal depressive history among women but not men. Youth social functioning was a partial mediator of both associations. In sum, the findings suggest that psychosocial factors observed in adolescence may contribute to the risk of experiencing severe intimate partner violence during young adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The experiences of Sudanese unaccompanied minors in foster care.

Sudanese unaccompanied minors were separated from their parents in childhood and lived apart from their families in refugee camps for close to a decade before being resettled in the United States. This phenomenological study examines the refugees’ experiences of living in American foster families after living in peer groups in the camps. Interviews with 18 young adults, 7 years after resettlement, revealed that nearly all of the youth struggled with parental authority initially, and nearly half of them changed placements because of relationship difficulties with their foster parents. Misunderstandings based on cultural differences often exacerbated conflicts. However, 15 of 18 youth currently had a positive relationship with at least 1 foster parent, sometimes with a parent from their second or third placement. Changing foster families is often considered a failure in the child welfare system, but several Sudanese youth reported that having supportive relationships helped them during the acculturation process whether those relationships developed during the first or last placement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The association between major depression and headache: results of a longitudinal epidemiologic study in youth

Retrospective epidemiologic research in adults suggests that a long-term association between major depression and headache arises during childhood or adolescence. This study uses data from a prospective epidemiologic study to examine the association between major depression and headache from late childhood into early adulthood. An epidemiologically selected sample of 776 youth, aged 9-18, was assessed psychiatrically in 1983 using DISC interviews with both youth and parent informants. Reassessments were conducted in 1985-1986 and 1992. Current and past histories of functionally impairing migraine or chronic headache were elicited in both 1985-1986 and 1992. Regression analyses examined the relationships between major depression and headache status. The prevalence of current functionally impairing headache was approximately 10% in both 1985-1986 and 1992. There were lifetime and cross-sectional associations between headache and major depression. Headache was approximately twice as common in depressed adolescents compared with nondepressed adolescents. Major depression in adolescents, without current or past headache, prospectively predicted the new onset of headaches in young adulthood. Among adolescents who had no history of chronic impairing headache in 1985-1986, those with current major depression faced a nearly tenfold increased risk of developing such headaches at some time during the next 7 years. Consistent with findings of retrospective studies among adults, a longitudinal/ developmental relationship between major depression and functionally impairing headache was found in this prospective epidemiologic study of youth. These findings suggest that (1) neurochemical and pharmacologic commonalities between depression and headache should receive further investigation and that (2) it may be clinically useful to inquire about family history of headache syndromes in adolescents with major depression because such questioning may provide insight about the risk of subsequent functionally impairing headache in a depressed adolescent.     

Development of a measure of drinking and driving expectancies for youth.

The present study constructs and provides initial validation for a measure of positive expectancies for drinking and driving for use with adolescents and young adults (PEDD-Y). In Study 1, items were generated through open-ended responses from high school- and college-age youth. Data collected from a 2nd sample of college students (n = 404) identified a 29 item, 4 factor questionnaire. Two of the PEDD-Y factors (Convenience, Avoiding Consequences) explained additional variance in drinking and driving behavior above and beyond other cognitions about drinking and driving. Study 2 extended these results to a high school sample (n = 185). Study 3 demonstrated test-retest reliability of the PEDD-Y in college-age youth (n = 165). These results provide initial evidence for the utility of the PEDD-Y in assessing drinking and driving risk in adolescents and college students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of age on memory for emotional faces.

Prior studies of emotion suggest that young adults should have enhanced memory for negative faces and that this enhancement should be reduced in older adults. Several studies have not shown these effects but were conducted with procedures different from those used with other emotional stimuli. In this study, researchers examined age differences in recognition of faces with emotional or neutral expressions, using trial-unique stimuli, as is typically done with other types of emotional stimuli. They also assessed the influence of personality traits and mood on memory. Enhanced recognition for negative faces was found in young adults but not in older adults. Recognition of faces was not influenced by mood or personality traits in young adults, but lower levels of extraversion and better emotional sensitivity predicted better negative face memory in older adults. These results suggest that negative expressions enhance memory for faces in young adults, as negative valence enhances memory for words and scenes. This enhancement is absent in older adults, but memory for emotional faces is modulated in older adults by personality traits that are relevant to emotional processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cranial growth in Homo erectus: how credible are the Ngandong juveniles?

Confusion exists regarding the developmental ages of numerous Asian and southeast Asian Homo erectus fossils because of Weidenreich's contention that Pithecanthropus fused its sutures prematurely relative to H. sapiens. I reevaluate the cranial developmental ages of the Ngandong "juveniles" (2, 5, 8, 9) based on a series of indicators of youth (superstructure development, suture development/fusion, and cranial thickness) and cranial contours. The Ngandong juveniles are compared with H. sapiens adults (n = 281) and subadults (n = 81) and with Ngandong and other H. erectus adults (n = 20) and subadults (n = 4). Cranial contours are assessed using bivariate plots of arc vs. chord measurements. All indicators suggest that Ngandong 5 and 9 are adults, whereas Ngandong 8 is an older juvenile or young adult and Ngandong 2 is a juvenile with a developmental age range of greater than 6 and less than 11 years. In addition, adult cranial contours and the pattern of contour development are similar between Ngandong adults and other H. erectus adults. There is nothing in the cranial contour data to suggest that Ngandong is, despite a relatively large brain, transitional in vault shape between H. erectus and H. sapiens.     

Aging, encoding specificity, and memory change in the Double Memory Test

Aged and young adults were tested by category cued recall after learning with category cues (CCR) or with item cues (ICR). CCR was about twice ICR for both aged and young adults. The aged recalled less than the young and did not benefit as much from greater encoding specificity and deeper processing in CCR. ICR and CCR were correlated, so that expected CCR can be predicted from ICR. The regression of CCR on ICR was linear for young adults, but was piecewise linear for the aged, showing that the relationship between ICR and CCR was not uniform for the aged adults. Lower than expected CCR by a subset of aged without clinical dementia may be a sign of preclinical dementia.     

Distress and self-restraint as measures of adjustment across the life span: Confirmatory factor analyses in clinical and nonclinical samples.

The Weinberger Adjustment Inventory (WAI; D. Weinberger & G. Schwartz, 1990) was designed as a hierarchical self-report measure of general social-emotional adjustment in older children and adults. The superordinate constructs of distress (i.e., anxiety, depression, low self-esteem, and low well-being) and self-restraint (i.e., impulse control, suppression of aggression, consideration of others, and responsibility) are each operationalized as a composite of 4 subscales. Confirmatory factor analyses were conducted using 6 samples (n?=?153–392; N?=?1,486). The factor structure was highly comparable with a mean comparative fit index (CFI) of .968 for youth (ages 10–17), young adults (ages 18–30), and adults (ages 31–65) within both clinical outpatient and nonclinical populations. The results suggest that there may be little justification for the routine practice of using different measures of general adjustment when investigating older children vs adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Picture naming by young children: norms for name agreement, familiarity, and visual complexity

Researchers concerned with the development of cognitive functions are in need of standardized material that can be used with both adults and children. The present article provides normative measures for 400 line drawings viewed by 5- and 6-year-old children. The three variables obtained-name agreement, familiarity, and visual complexity-are important because of their potential effect on memory and other cognitive processes. The normative data collected in the present study indicate that young children are different from adults in both the name most frequently assigned and the number of alternative names provided. The alternative names given by the children are either coordinate names or names of objects that are visually similar to the pictured object. In addition, the failure (to name) rate is higher among young children compared to adults. Thus, we conclude that unequivocal interpretation of age-related differences in cognitive functions can be made only when age-appropriate pictorial stimuli are chosen.     

Aging and fluency-based illusions in recognition memory.

We examined age-related differences in susceptibility to fluency-based memory illusions. The results from 2 experiments, in which 2 different methods were used to enhance the fluency of recognition test items, revealed that older and young adults did not differ significantly in terms of their overall susceptibility to this type of memory illusion. Older and young adults were also similar in that perceptual fluency did not influence recognition memory responses when there was a mismatch in the sensory modality of the study and test phases. Likewise, a more conceptual fluency manipulation influenced recognition memory responses in both older and young adults regardless of the match in modality. Overall, the results indicate that older adults may not be more vulnerable than young adults to fluency-based illusions of recognition memory. Moreover, young and older adults appear to be comparable in their sensitivity to factors that modulate the influence of fluency on recognition decisions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and interference in verbal working memory.

According to inhibitory views of working memory, old adults should have particular problems deleting irrelevant information from working memory, leading to greater interference effects compared with young adults. The authors investigated this hypothesis by using variations of an A-B, C-D retroactive interference paradigm in working memory with young and old adults. They used a recognition measure of memory, assessing both accuracy and reaction time. The primary finding was that senior adults consistently exhibited proportionally greater retroactive interference effects compared with young adults when interfering word pairs that had been read aloud had to be rejected. Patterns of recognition and reaction time data suggested that old adults' activation of target material is similar to young adults, but they experience sustained activation of irrelevation material that has entered working memory. Theoretical implications of these findings for inhibitory deficit (R.T. Zacks & L. Hasher, 1998) and source memory deficit accounts of cognitive aging are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adverse life events and resilience

OBJECTIVE: Adverse life events are well-documented risk factors of psychopathology and psychological dysfunction in children and adolescents. Youth with good adjustment despite high levels of adverse life events are considered resilient. This study identifies factors that characterize resilience. METHOD: Household probability samples of youth aged 9 through 17 years at four sites were used. Main and interaction effects of 11 factors were examined to assess their impact on youth adjustment. RESULTS: Children at risk because of higher levels of adverse life events exhibited a greater degree of resilience when they had a higher IQ, better family functioning, closer parental monitoring, more adults in the household, and higher educational aspiration. The interaction between maternal psychopathology and adversity was significant, and the interaction between IQ and adversity approached significance. CONCLUSION: Resilient youth received more guidance and supervision by their parents and lived in higher-functioning families. Other adults in the family probably complemented the parents in providing guidance and support to the youth and in enhancing youth adjustment. Higher educational aspirations might have provided high-risk youth with a sense of direction and hope. Although IQ had no impact in youth at low risk, youth at high risk who had a higher IQ might have coped better.     

Inefficient postural responses to unexpected slips during walking in older adults

BACKGROUND: Slips account for a high percentage of falls and subsequent injuries in community-dwelling older adults but not in young adults. This phenomenon suggests that although active and healthy older adults preserve a mobility level comparable to that of young adults, these older adults may have difficulty generating efficient reactive postural responses when they slip. This study tested the hypothesis that active and healthy older adults use a less effective reactive balance strategy than young adults when experiencing an unexpected forward slip occurring at heel strike during walking. This less effective balance strategy would be manifested by slower and smaller postural responses, altered temporal and spatial organization of the postural responses, and greater upper trunk instability after the slip. METHODS: Thirty-three young adults (age range=19-34 yrs, mean=25+/-4 yrs) and 32 community-dwelling older adults (age range=70-87 yrs, mean=74+/-14 yrs) participated. Subjects walked across a movable forceplate which simulated a forward slip at heel strike. Surface electromyography was recorded from bilateral leg, thigh, hip, and trunk muscles. Kinematic data were collected from the right (perturbed) side of the body. RESULTS: Although the predominant postural muscles and the activation sequence of these muscles were similar between the two age groups, the postural responses of older adults were of longer onset latencies, smaller magnitudes, and longer burst durations compared to young adults. Older adults also showed a longer coactivation duration for the ankle, knee, and trunk agonist/antagonist pairs on the perturbed side and for the knee agonist/antagonist pair on the nonperturbed side. Behaviorally, older adults became less stable after the slips. This was manifested by a higher incidence of being tripped (21 trials in older vs 5 trials in young adults) and a greater trunk hyperextension with respect to young adults. Large arm elevation was frequently used by older adults to assist in maintaining trunk stability. In an attempt to quickly reestablish the base of support after the slips, older adults had an earlier contralateral foot strike and shortened stride length. CONCLUSION: The combination of slower onset and smaller magnitude of postural responses to slips in older adults resulted in an inefficient balance strategy. Older adults needed secondary compensatory adjustments, including a lengthened response duration and the use of the arms, to fully regain balance and prevent a fall. The shorter stride length and earlier contralateral foot strike following the slip indicate use of a more conservative balance strategy in older adults.     

I'm better off than most other people: The role of social comparisons for coping with regret in young adulthood and old age.

This longitudinal study was designed to examine the importance of social comparisons for coping with regret among young and older adults. It was expected that making downward social comparisons would be associated with a greater reduction in regret intensity over time among older, compared with young, adults. A total of 104 participants took part in this 4-month longitudinal study. The findings suggest that across different comparison targets, making downward (relative to upward) social comparisons was consistently related to reduced regret intensity over time among older adults. Among young adults, making downward social comparisons with personally known others, as opposed to age peers, was associated with lower regret intensity. In addition, older adults increased their reliance on downward social comparisons over time. This age-differential shift toward downward social comparisons further explained age differences in changes of regret intensity over time. Finally, differences in opportunities to undo regrets explained some of the age differences in the use and adaptive value of downward social comparisons. The implications of the findings for understanding and examining pathways to successful development are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

DSM-III-R tobacco dependence and quitting during late adolescence

Previous studies of tobacco dependence have tended not to examine adolescent samples. In a cohort of 18-year-olds, the 12-month prevalence rate of dependence based on DSM-III-R criteria was found to be 19.3%. Cotinine levels in saliva were positively related to level of cigarette consumption but not to tobacco dependence and may not be a suitable measure of dependence. Measures of behavioral and psychological aspects of smoking supported the utility of DSM-III-R criteria for tobacco dependence among young smokers. As a large number of young smokers are dependent on tobacco. the results support the development of treatment programmes for youth that take into consideration their degree of dependence.     

Mutations in the iduronate-2-sulfatase gene in five Norwegians with Hunter syndrome

OBJECTIVES: Adolescents with human immunodeficiency virus (HIV) infection are at increased risk for tuberculosis (TB), underscoring the importance of early identification of TB infection. The goals of this study were to assess the factors associated with the completion of evaluations for TB in a cohort of HIV-positive adolescents and young adults and to describe the prevalence of Mycobacterium tuberculosis infection and adherence to antituberculous treatment regimens. METHODS: A retrospective chart review was done for all HIV-positive adolescents and young adults, ages 13 to 21 years (n = 49), seen in a comprehensive care program from January 1991 through December 1992. Data collected included CD4 cell count, HIV clinical status, living situation, substance use history, and the completion of an annual evaluation for TB infection. The evaluation consisted of a tuberculin skin test (Mantoux test), using an intraepidermal injection of 0.1 mL of 5 tuberculin units of purified protein derivative (PPD) and a simultaneous Merieux multitest anergy panel. Chi-square analysis was used to assess the association between the completion of the evaluation for TB and both living status and substance use. RESULTS: Thirty-one (63%) of 49 patients completed evaluations for TB. Of the 31 completed evaluations, 18 were assessed by clinic staff on site, and 13 were assessed by other medical or trained nonmedical observers through community networking efforts. Neither homelessness nor illicit substance use were factors in the completion of the evaluation. Six (19%) of the 31 patients had positive PPD skin test results. Three had medical histories and chest radiographs suggesting active TB, and all were hospitalized for at least 2 weeks. Two had positive cultures for M tuberculosis, although the third also responded clinically to antituberculous therapy. All three were otherwise asymptomatic for HIV infection, with only moderately depressed CD4 cell counts. All three were homeless and used crack cocaine. After the initial treatment as inpatients, none completed treatment within the prescribed time period. CONCLUSIONS: The completions of the evaluations for TB were greatly facilitated by community networking, but innovative strategies to enhance both screening and treatment programs, such as training youth service providers in the community to read PPD skin tests, expansion of directly observed therapy services, and youth-centered programs for housing and substance use, need further development. The high prevalence of TB in the cohort underscores the need for providers to increase efforts to identify cases of TB infection among adolescents and young adults and to incorporate HIV risk assessment, counseling, and testing into their practices routinely.     

Age of onset of first alcohol intoxication and subsequent alcohol use among urban American Indian adolescents.

The objective was to assess the effect of early onset intoxication on subsequent alcohol involvement among urban American Indian youth. The data come from the American Indian Research (AIR) project, a panel study of urban Indian youth residing in King County, Washington. Data were collected annually from the adolescent and his/her primary caregiver from the 1988–89 school year to the 1996–97 school year, providing a total of nine waves of data. Early intoxication (by age 14) was related to delinquency, family history of alcohol abuse or dependence, poverty, broken family structure, less family cohesiveness, and more family conflict. The effects of these characteristics were, therefore, partialed out in testing effects of early intoxication on later alcohol involvement. Two-part latent growth models of alcohol use and alcohol problems were specified. Effects of early onset intoxication on these trajectories, as well as lifetime alcohol abuse or dependence by the transition to young adulthood, were examined. Findings indicate that adolescents who experienced their first intoxication early (by age 14), used alcohol more heavily from the ages of 16 to 18, experienced more problems related to the alcohol's use from the ages of 16 to 18, and were more likely to have a diagnosed alcohol disorder by the final wave of data collection. Congruent with similar studies in the general population, early intoxication appears to be associated with a deleterious course of alcohol involvement during adolescence and into the transition to young adulthood among urban American Indian youth. Implications for prevention are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

虚拟样机技术在大型液压泥炮研发过程中的应用

借助虚拟样机技术,运用Solidworks建立了新型液压泥炮的虚拟样机模型,并将模型导入ADAMS软件对其进行运动学、动力学仿真分析,研究了关键点的运动轨迹及其速度变化,分析了主要零部件铰接点的受力大小和变化趋势。通过样机建模与仿真分析,为大型液压泥炮的合理设计和使用提供了可靠的依据,同时也缩短了开发周期,降低成本。