Global variability and controls on the accumulation of fallout radionuclides in cryoconite.

The accumulation of fallout radionuclides (FRNs) from nuclear weapons testing and nuclear accidents has been evaluated for over half a century in natural environments; however, until recently their distribution and abundance within glaciers have been poorly understood. Following a series of individual studies of FRNs, specifically 137Cs, 241Am and 210Pb, deposited on the surface of glaciers, we now understand that cryoconite, a material commonly found in the supraglacial environment, is a highly efficient accumulator of FRNs, both artificial and natural. However, the variability of FRN activity concentrations in cryoconite across the global cryosphere has never been assessed. This study thus aims to both synthesize current knowledge on FRNs in cryoconite and assess the controls on variability of activity concentrations. We present a global database of new and previously published data based on gamma spectrometry of cryoconite and proglacial sediments, and assess the extent to which a suite of environmental and physical factors can explain spatial variability in FRN activity concentrations in cryoconite. We show that FRNs are not only found in cryoconite on glaciers within close proximity to specific sources of radioactivity, but across the global cryosphere, and at activity concentrations up to three orders of magnitude higher than those found in soils and sediments in the surrounding environment. We also show that the organic content of cryoconite exerts a strong control on accumulation of FRNs, and that activity concentrations in cryoconite are some of the highest ever described in environmental matrices outside of nuclear exclusion zones, occasionally in excess of 10,000 Bq kg-1. These findings highlight a need for significant improvements in the understanding of the fate of legacy contaminants within glaciated catchments. Future interdisciplinary research is required on the mechanisms governing their accumulation, storage, and mobility, and their potential to create time-dependent impacts on downstream water quality and ecosystem sustainability.

Attachment, autonomy, and multifinality in adolescent internalizing and risky behavioral symptoms.

A diathesis-stress interaction model is used to describe multifinality in adolescent internalizing and risky behavioral outcomes. Problematic behavior associated with adolescent insecure preoccupation (a diathesis) was expected to interact with the level of maternal autonomous discourse (a stressor) to predict specific adolescent outcomes. Assessments of adolescent preoccupied attachment organization, observations of maternal displays of autonomy in mother-adolescent interactions, and adolescent reports of internalizing symptoms and risky behaviors were obtained at age 16. As predicted, maternal autonomy in the mother-adolescent relationship helped to explain multifinality in dysfunctional symptoms among preoccupied adolescents. Adolescent preoccupation was more strongly linked to internalizing behavior when mothers demonstrated low levels of autonomy in interactions with their adolescents and more strongly linked to risky behavior when mothers displayed extremely high levels of autonomy. Implications for autonomy processes in increasing our understanding of how adolescent insecure-preoccupation relates to profiles of specific problems during adolescence are discussed as is the importance of exploring the role of attachment in different contexts.

The emotional experience of intercourse and sexually transmitted diseases: a decision-tree analysis.

BACKGROUND: Epidemiologic data document high risks for many sexually transmitted diseases (STDs) among US adolescents and young adults. GOAL: This case-control study used decision trees to investigate the relationship between STD incidence and emotional reactions to intercourse. STUDY DESIGN: For this study, 188 adolescents and young adults (mean age, 24.9 years [SD = 8.2]) at a regional public STD clinic completed a behavioral and psychological questionnaire and underwent a workup for STD. RESULTS: The prevalence of STD in this group was 44.8%. Decision-tree analysis identified emotional reactions to intercourse that were associated with STD diagnosis for some patients: feeling good about oneself after sex half the time or less (OR = 3.21; 95% CI = 1.73-5.95), feeling comfortable during sex half the time or less (OR = 2.17; 95% CI = 1.07-4.40), and feeling angry after sex (OR = 1.90; 95% CI = 0.91-3.99). Findings of a logistic regression model of emotional reactions to intercourse were significant (chi-square = 24.6; df = 8; P < 0.002), but adding behavioral variables did not improve prediction. CONCLUSIONS: For some of these young adults at the time of life when they are at highest risk of STD, emotional factors have higher odds ratios for STD diagnosis than the traditionally assessed behavioral variables. This underscores the need for interventions targeted to specific subgroups and for readily available mental health services.

A secure base in adolescence: markers of attachment security in the mother-adolescent relationship.

This study sought to identify ways in which adolescent attachment security, as assessed via the Adult Attachment Interview, is manifest in qualities of the secure base provided by the mother-adolescent relationship. Assessments included data coded from mother-adolescent interactions, test-based data, and adolescent self-reports obtained from an ethnically and socioeconomically diverse sample of moderately at-risk 9th and 10th graders. This study found several robust markers of adolescent attachment security in the mother-adolescent relationship. Each of these markers was found to contribute unique variance to explaining adolescent security, and in combination, they accounted for as much as 40% of the raw variance in adolescent security. These findings suggest that security is closely connected to the workings of the mother-adolescent relationship via a secure-base phenomenon, in which the teen can explore independence in thought and speech from the secure base of a maternal relationship characterized by maternal attunement to the adolescent and maternal supportiveness.

Attachment and autonomy as predictors of the development of social skills and delinquency during midadolescence.

This study examined adolescent attachment organization as a predictor of the development of social skills and delinquent behavior during midadolescence. Delinquent activity and skill levels were assessed for 117 moderately at-risk adolescents at ages 16 and 18, and maternal and adolescent attachment organization and autonomy in interactions were assessed at age 16. Adolescent attachment security predicted relative increases in social skills from age 16 to 18, whereas an insecure-preoccupied attachment organization predicted increasing delinquency during this period. In addition, preoccupied teens interacting with highly autonomous mothers showed greater relative decreases in skill levels and increases in delinquent activity over time, suggesting a heightened risk for deviance among preoccupied teens who may be threatened by growing autonomy in adolescent-parent interactions.