Deep-Focus Earthquakes and Recycling of Water into the Earth's Mantle

For more than 50 years, observations of earthquakes to depths of 100 to 650 kilometers inside Earth have been enigmatic: at these depths, rocks are expected to deform by ductile flow rather than brittle fracturing or frictional sliding on fault surfaces. Laboratory experiments and detailed calculations of the pressures and temperatures in seismically active subduction zones indicate that this deep-focus seismicity could originate from dehydration and high-pressure structural instabilities occurring in the hydrated part of the lithosphere that sinks into the upper mantle. Thus, seismologists may be mapping the recirculation of water from the oceans back into the deep interior of our planet.

HIV risk behavior among adults with severe mental illness: A systematic review

Adults with severe mental illness (SMI) have been disproportionately affected by the HIV/AIDS epidemic. This systematic review of the empirical literature on SMI documents the prevalence and correlates of HIV risk behaviors, discusses clinical implications for HIV prevention, and recommends directions for future research. Prevalence rates of HIV risk behaviors were estimated using weighted means, and findings on correlates were synthesized. Across reviewed studies (N=52), the majority of adults with SMI were sexually active, and many engaged in risk behaviors associated with HIV transmission (e.g., unprotected intercourse, multiple partners, injection drug use). HIV risk behaviors were correlated with factors from the following domains: psychiatric illness, substance use, childhood abuse, cognitive-behavioral factors, and social relationships. A proposed model illustrates the multiple pathways linking these domains to HIV risk behavior. Further research using improved methodologies (e.g., longitudinal designs, standardized measures, multivariate analyses) is needed to examine the broader social context in which HIV risk behavior occurs and identify underlying processes. HIV prevention efforts targeting adults with SMI must occur on multiple levels (e.g., individual, group, community, structural/policy), address several domains of influence (e.g., psychiatric illness, trauma history, social relationships), and be integrated into existing services (e.g., psychotherapy, substance abuse treatment, housing programs).

Adolescent oral sex, peer popularity, and perceptions of best friends' sexual behavior

OBJECTIVE

To provided initial descriptive information regarding adolescents' engagement in oral sex and to investigate adolescents' perceptions of their best friends' sexual behavior and peer-reported popularity as two social mechanisms that may influence engagement in oral sex.

METHODS

A total of 212 tenth graders reported their engagement in oral sex and intercourse, number of sexual partners, and use of sexually transmitted infection (STI) protection, as well as perceptions of their best friends' sexual behaviors. Sociometric assessment yielded peer-reported measures of adolescents' preference- and reputation-based popularity.

RESULTS

Adolescents were more likely to report engagement in oral sex than intercourse, report more oral sex partners than intercourse partners, and were unlikely to report use of STI protection during oral sex. Perceptions of best friends' behavior were significantly associated with adolescents' own oral sex behavior, but not intercourse. Adolescents who reported sexual activity had high levels of reputation-based popularity, but not likeability among peers; however, sex with more partners was associated with lower levels of popularity.

CONCLUSIONS

Implications for prevention programs are discussed.

Rupture Characteristics of the Deep Bolivian Earthquake of 9 June 1994 and the Mechanism of Deep-Focus Earthquakes

The M(w) = 8.3 deep (636 kilometers) Bolivian earthquake of 9 June 1994 was the largest deep-focus earthquake ever recorded. Seismic data from permanent stations plus portable instruments in South America show that rupture occurred on a horizontal plane and extended at least 30 by 50 kilometers. Rupture proceeded at 1 to 3 kilometers per second along the down-dip azimuth of the slab and penetrated through more than a third of the slab thickness. This extent is more than three times that expected for a metastable wedge of olivine at the core of the slab, and thus appears to be incompatible with an origin by transformational faulting. These large events may instead represent slip on preserved zones of weakness established in oceanic lithosphere at the Earth's surface.

Identification of Racial Inequities in Access to Specialized Inpatient Heart Failure Care at an Academic Medical Center

BACKGROUND

Racial inequities for patients with heart failure (HF) have been widely documented. HF patients who receive cardiology care during a hospital admission have better outcomes. It is unknown whether there are differences in admission to a cardiology or general medicine service by race. This study examined the relationship between race and admission service, and its effect on 30-day readmission and mortality Methods: We performed a retrospective cohort study from September 2008 to November 2017 at a single large urban academic referral center of all patients self-referred to the emergency department and admitted to either the cardiology or general medicine service with a principal diagnosis of HF, who self-identified as white, black, or Latinx. We used multivariable generalized estimating equation models to assess the relationship between race and admission to the cardiology service. We used Cox regression to assess the association between race, admission service, and 30-day readmission and mortality.

RESULTS

Among 1967 unique patients (66.7% white, 23.6% black, and 9.7% Latinx), black and Latinx patients had lower rates of admission to the cardiology service than white patients (adjusted rate ratio, 0.91; 95% CI, 0.84-0.98, for black; adjusted rate ratio, 0.83; 95% CI, 0.72-0.97 for Latinx). Female sex and age >75 years were also independently associated with lower rates of admission to the cardiology service. Admission to the cardiology service was independently associated with decreased readmission within 30 days, independent of race.

CONCLUSIONS

Black and Latinx patients were less likely to be admitted to cardiology for HF care. This inequity may, in part, drive racial inequities in HF outcomes.

The intergenerational cycle of teenage motherhood: an ecological approach

OBJECTIVE

Daughters of teenage mothers have increased risk for teenage childbearing, perpetuating intergenerational cycles. Using Ecological Systems Theory, this study prospectively examined risk factors for teenage childbearing among a national sample of adolescent girls.

DESIGN

Data came from the National Longitudinal Survey of Youth 1997. Participants (N = 1,430) were recruited in early adolescence and interviewed yearly for 6 years. Survival analysis was used to examine the rate of childbirth across the teenage years by maternal age at first birth. Hierarchical Cox regression was used to identify multivariate predictors of teenage childbearing and to test whether risk factors differed between daughters of teenage versus older mothers.

PRIMARY OUTCOME MEASURE

Age at first childbirth was based on cumulative information collected at yearly interviews.

RESULTS

Daughters of teenage mothers were 66% more likely to become teenage mothers, after accounting for other risks. Individual (school performance), family (maternal education, marital status, number of children), peer (dating history), and environmental (race, enrichment) factors predicted teenage childbearing. Risks unique to daughters of teenage mothers were deviant peer norms, low parental monitoring, Hispanic race, and poverty.

CONCLUSION

Results support multidimensional approaches to pregnancy prevention, and targeted interventions addressing unique risk factors among daughters of teenage mothers.

Systematic review of sexual risk among pregnant and mothering teens in the USA: pregnancy as an opportunity for integrated prevention of STD and repeat pregnancy

Behaviors that lead to teen pregnancy also place young women at risk for STDs and repeat pregnancy. Compared to the broad literature on adolescent sexual risk behavior, our understanding of sexual risk in pregnant/mothering teens lags far behind. Primary objectives of this systematic review (1981-2003) of pregnant/mothering teens were to: (1) document rates of STD, repeat pregnancy, condom use, and contraception; (2) identify correlates of these biological and behavioral outcomes; (3) review sexual risk reduction interventions; and (4) discuss directions for future research and implications for clinical care. Fifty-one studies met inclusion criteria. Rates of STD and repeat pregnancy were high, with the majority of teens engaging in unprotected sex during and after pregnancy. An Ecological Model of Sexual Risk, based on Bronfenbrenner's (1989) Ecological Systems Theory, was proposed to organize findings on correlates of sexual risk. Improvements in research, including integration of outcomes and risk factors, stronger methodologies, and standardized assessments, are essential. Results suggest that teen pregnancy is a marker for future sexual risk behavior and adverse outcomes, and that pregnant/mothering teens need hybrid interventions promoting dual use of condoms and hormonal contraception. Pregnancy may provide a critical "window of opportunity" for sexual risk reduction.

Adherence to HAART among patients with HIV: breakthroughs and barriers

Highly active antiretroviral therapy (HAART) has been a major breakthrough for the treatment of patients with HIV; however, adherence to treatment remains a formidable barrier. This paper evaluates the current state-of-the-science in adherence to HAART. Barriers to treatment success, determinants of adherence and interventions to improve adherence are reviewed. Overall, multifaceted interventions appear most promising. We conclude with recommendations to enhance clinical practice and improve treatment outcomes for patients with HIV. Despite substantial attention to adherence in recent years, much more remains to be done to understand and promote adherence to HAART.

Mental health treatment to reduce HIV transmission risk behavior: a positive prevention model

Secondary HIV prevention, or "positive prevention," is concerned with reducing HIV transmission risk behavior and optimizing the health and quality of life of people living with HIV/AIDS (PLWHA). The association between mental health and HIV transmission risk (i.e., sexual risk and poor medication adherence) is well established, although most of this evidence is observational. Further, a number of efficacious mental health treatments are available for PLWHA yet few positive prevention interventions integrate mental health treatment. We propose that mental health treatment, including behavioral and pharmacologic interventions, can lead to reductions in HIV transmission risk behavior and should be a core component of secondary HIV prevention. We present a conceptual model and recommendations to guide future research on the effect of mental health treatment on HIV transmission risk behavior among PLWHA.

Outcomes from a group intervention for coping with HIV/AIDS and childhood sexual abuse: reductions in traumatic stress

Childhood sexual abuse is common among HIV-infected persons, though few empirically supported treatments addressing sexual abuse are available for men and women with HIV/AIDS. This study reports the outcome from a randomized controlled trial of a group intervention for coping with HIV and sexual abuse. A diverse sample of 202 HIV-positive men and women who were sexually abused as children was randomly assigned to one of three conditions: a 15-session HIV and trauma coping group intervention, a 15-session support group comparison condition, or a waitlist control (later randomly assigned to an intervention condition). Traumatic stress symptoms were assessed at baseline and post-intervention, with analysis conducted for the three-condition comparison followed by analysis of the two-condition comparison between the coping and support group interventions. Participants in the coping group intervention exhibited reductions in intrusive traumatic stress symptoms compared to the waitlist condition and in avoidant traumatic stress symptoms compared to the support group condition. No differences were found between the support group intervention and waitlist conditions. Tests of clinical significance documented the meaningfulness of change in symptoms.

Urban teens: Trauma, posttraumatic growth, and emotional distress among female adolescents

Urban teens face many traumas, with implications for potential growth and distress. This study examined traumatic events, posttraumatic growth, and emotional distress over 18 months among urban adolescent girls (N = 328). Objectives were to (a) describe types of traumatic events, (b) determine how type and timing of events relate to profiles of posttraumatic growth, and (c) prospectively examine effects of event type and posttraumatic growth on short- and long-term emotional distress with controls for pre-event distress. Results indicate that type of event was related to profiles of posttraumatic growth, but not with subsequent emotional distress. When baseline emotional distress was controlled, posttraumatic growth was associated with subsequent reductions in short- and long-term emotional distress. Implications for future research and clinical practice with adolescents are addressed.

High-Temperature Phase Transition and Dissociation of (Mg, Fe)SiO 3 Perovskite at Lower Mantle Pressures

To study the crystallography of Earth's lower mantle, techniques for measuring synchrotron x-ray diffraction from a laser-heated diamond anvil cell have been developed. Experiments on samples of (Mg, Fe)SiO(3) show that silicate perovskite maintains its orthorhombic symmetry at 38 gigapascals and 1850 kelvin. Measurements at 65 and 70 gigapascals provide evidence for a temperature-induced orthorhombic-to-cubic phase transition and dissociation to an assemblage of perovskite and mixed oxides. If these phase transitions occur in Earth, they will require a significant change in mineralogical models of the lower mantle.

Adherence to antiretroviral therapy among patients with HIV: a critical link between behavioral and biomedical sciences

Rapid advances in biomedical science, such as pharmaceutical developments for HIV disease, must be integrated with advances in behavioral science to further our understanding of medication adherence. This article evaluates the current state of the science in adherence to antiretroviral therapy for persons with HIV. The primary objectives are to 1) identify critical determinants of adherence, and 2) describe interventions to improve adherence. Adherence is a complex dynamic behavior influenced by characteristics of the patient, treatment regimen, disease, patient-provider relationship, and clinical setting. Therefore, the most promising interventions are multifaceted and target different locations in this matrix simultaneously. Unfortunately, nonadherence remains a formidable barrier in the management of HIV, resulting in the development of resistance and drug failure. Moreover, adherence is a public health concern, with implications for the transmission of HIV in general and the transmission of drug-resistant strains of HIV specifically. Despite substantial attention to adherence in recent years, much more remains to be done to better understand and promote adherence to antiretroviral therapy through effective interventions. From this integration of biomedical and behavioral science, effective clinical interventions can be developed and implemented to enhance the health of patients with HIV.

Long-term correlates of childhood abuse among adults with severe mental illness: adult victimization, substance abuse, and HIV sexual risk behavior

The prevalence of childhood sexual and physical abuse among persons with severe mental illness (SMI) is disproportionately high. Adults with SMI also engage in high rates of HIV risk behaviors. This study examined the association between childhood abuse and adult victimization, substance abuse, and lifetime HIV sexual risk in a sample of 152 adults with SMI receiving community mental health services. Structured interviews assessed psychiatric, psychosocial, and behavioral risk factors. Seventy percent reported childhood physical and/or sexual abuse, and 32% reported both types of abuse. Participants with childhood abuse were more likely to report adult victimization and greater HIV risk. A structural equation model found that childhood abuse was directly and indirectly associated with HIV risk through drug abuse and adult vicitimization. Integrated treatment approaches that address interpersonal violence and substance abuse may be necessary for HIV risk reduction in this population.

Psychosocial predictors of sexual HIV transmission risk behavior among HIV-positive adults with a sexual abuse history in childhood

Childhood sexual abuse (CSA) is associated with HIV sexual risk behavior. Although many psychosocial correlates of sexual risk among HIV-positive persons have been identified, studies predicting continued risk among HIV-positive adults with histories of CSA are limited. This cross-sectional study identified variables predictive of sexual transmission risk behavior among an ethnically diverse sample of 256 HIV-positive adults (women and men who have sex with men; MSM) with CSA histories. Participants were assessed for trauma symptoms, shame related to HIV and sexual trauma, substance use, coping style, and sexual risk behavior. Logistic regression analyses were conducted to identify variables predictive of unprotected sexual behavior in the past 4 months. Unprotected sex was significantly associated with substance use and trauma-related behavioral difficulties among women and men, and less spiritual coping among men. Unprotected sex with HIV negative or serostatus unknown partners was significantly associated with greater trauma-related behavioral difficulties, more HIV-related shame, and fewer active coping strategies. Thus, trauma symptoms, shame, coping style, and substance use were significantly associated with sexual risk behavior among HIV-positive adults with histories of CSA, with models of prediction differing by gender and partner serostatus. HIV prevention intervention for persons with HIV and CSA histories should address trauma-related behavioral difficulties and enhance coping skills to reduce sexual transmission risk behavior.

fMRI brain activation during a delay discounting task in HIV-positive adults with and without cocaine dependence

Cocaine use is associated with poorer HIV clinical outcomes and may contribute to neurobiological impairments associated with impulsive decision making. This study examined the effect of cocaine dependence on brain activation during a delay discounting task involving choices between smaller immediate rewards and larger delayed ones. Participants were 39 HIV-positive adults on antiretroviral therapy who had current cocaine dependence ("active," n=15), past cocaine dependence ("recovered," n=13), or no lifetime substance dependence ("naïve," n=11). Based on responses on a traditional delay discounting task, three types of choices were individualized for presentation during functional magnetic resonance imaging: hard (similarly valued), easy (disparately valued), and no (single option). Active participants had significantly smaller increases in activation than naïve participants during hard versus easy choices bilaterally in the precentral gyrus and anterior cingulate cortex and in the right frontal pole (including dorsolateral, ventrolateral, and orbitofrontal cortex). During hard and easy choices relative to no choices, active participants had smaller increases in activation compared to naïve participants in frontoparietal cortical regions. These deficits in the executive network during delay discounting choices may contribute to impulsive decision making among HIV-positive cocaine users, with implications for risk behaviors associated with disease transmission and progression.

A randomized controlled trial of a coping group intervention for adults with HIV who are AIDS bereaved: Longitudinal effects on grief

The authors sought to study the longitudinal effects of a cognitive-behavioral group intervention for coping with AIDS bereavement among a diverse sample of adults who were HIV positive. Participants (N = 267) were randomly assigned to receive the 12-week intervention or individual therapy upon request. Measures were administered at baseline, postintervention, and 4-, 8-, and 12-month follow-ups. Longitudinal data were analyzed with linear mixed models to examine change in grief by condition across the study period and the effect of the intervention on grief through its interaction with psychiatric distress. The authors used the Grief Reaction Index to assess grief and the Symptom Checklist-90-Revised to assess global psychiatric distress. Participants in both conditions reported decreases in grief severity. However, among those with higher levels of psychiatric distress, participants in the group intervention had significantly lower grief severity scores compared with participants in the individual therapy condition. The long-term effectiveness of this AIDS-bereavement intervention for psychiatrically distressed people with HIV/AIDS supports the need for tailored interventions among those at risk for complicated grief responses.

HIV risk behavior among patients with co-occurring bipolar and substance use disorders: associations with mania and drug abuse

BACKGROUND

Bipolar and substance use disorders frequently co-occur, and both are associated with impulsivity, impaired judgment, and risk-taking.

OBJECTIVES

This study aimed to: (1) describe the rates of HIV sexual and drug risk behaviors among patients with co-occurring bipolar and substance use disorders, (2) test whether acute mania, psychiatric severity, and drug severity independently predict HIV risk, and (3) examine the relationship between specific substance dependencies and sexual risk behaviors.

METHOD

Participants (N=101) were assessed for psychiatric diagnoses, substance abuse, and HIV risk behavior using structured clinical interviews and self-report questionnaires.

RESULTS

The majority (75%) were sexually active in the past 6 months and reported high rates of sexual risk behaviors, including unprotected intercourse (69%), multiple partners (39%), sex with prostitutes (24%, men only), and sex trading (10%). In a multivariate linear regression model, recent manic episode, lower psychiatric severity, and greater drug severity were independent predictors of total HIV risk. Cocaine dependence was associated with increased risk of sex trading.

CONCLUSIONS

Results underscore the importance of HIV prevention for this population.

Synchrotron Infrared Absorbance Measurements of Hydrogen in MgSiO 3 Perovskite

Micro-infrared spectroscopic measurements on single crystals of MgSiO(3) perovskite document two pleochroic hydroxyl absorbance peaks at 3483 and 3423 centimeter(-1). These measurements were obtained with the use of a synchrotron infrared source for spectroscopy. These data are consistent with a trace hydrogen content of 700 +/- 170 hydrogen atoms per 10(6) silicon atoms in the nominally anhydrous MgSiO(3) perovskite. When integrated over the volume of the lower mantle, this concentration is comparable to 12 percent of the mass of hydrogen in the Earth's hydrosphere.

Improvements in health-related quality of life following a group intervention for coping with AIDS-bereavement among HIV-infected men and women

BACKGROUND

AIDS-related bereavement is a severe life stressor that may be particularly distressing to persons themselves infected with HIV. Increasing evidence suggests that psychological health is associated with disease progression, HIV-related symptoms, and mortality.

PURPOSE

This study assessed change in health-related quality of life among HIV + persons following a group intervention for coping with AIDS-related loss.

METHODS

The sample included 235 HIV + men and women of diverse ethnicities and sexual orientations who had experienced an AIDS-related loss within the previous 2 years. Participants were randomly assigned to a 12-week cognitive-behavioral bereavement coping group intervention or offered individual psychotherapy upon request. Quality of life was assessed at baseline and 2 weeks after the intervention.

RESULTS

Participants in the group intervention demonstrated improvements in general health-related and HIV-specific quality of life, while those in the comparison remained the same or deteriorated. Effect sizes indicated that the majority of change occurred in women.

CONCLUSION

This bereavement group aimed at improving coping with grief also had a positive impact on health-related quality of life among HIV + men and women, and suggests that cognitive-behavioral interventions may have a broad impact on both emotional and physical health.

Psychiatric and psychosocial correlates of sexual risk behavior among adults with severe mental illness

Persons with severe mental illness (SMI) are disproportionately affected by HIV/AIDS. This study examined multivariate correlates of sexual risk among 152 adults with SMI receiving outpatient psychiatric treatment. Structured interviews assessed psychiatric, psychosocial, and behavioral risk factors. The majority was sexually active (65%), and many reported unprotected intercourse (73%), multiple partners (45%), and sex trading (21%) in the past year. Logistic regression models found that sexual behaviors were differentially associated with non-psychotic disorder, psychiatric symptoms, substance abuse, childhood sexual abuse, romantic partnership, and social support (all ps < .05). Findings underscore the need for targeted HIV prevention interventions that address psychiatric and psychosocial risk factors.

Reductions in traumatic stress following a coping intervention were mediated by decreases in avoidant coping for people living with HIV/AIDS and childhood sexual abuse

OBJECTIVE

To examine whether (a) Living in the Face of Trauma (LIFT), a group intervention to address coping with HIV and childhood sexual abuse (CSA), significantly reduced traumatic stress over a 1-year follow-up period more than an attention-matched support group comparison intervention; and (b) reductions in avoidant coping over time mediated reductions in traumatic stress.

METHOD

In a randomized controlled trial, 247 participants completed measures of traumatic stress and avoidant coping at pre- and post intervention, and at 4-, 8-, and 12-month follow-ups. Latent growth curve modeling examined changes over the 5 time points; standardized path coefficients provide estimates of effects.

RESULTS

As compared with the support intervention, the coping intervention led to a reduction in traumatic stress over time (b = -.20, p < .02). Participants in the coping intervention also reduced their use of avoidant coping strategies more than did participants in the support intervention (b = -.22, p < .05). Mediation analyses showed reductions in avoidant coping related to reductions in traumatic stress (b = 1.45, p < .001), and the direct effect of the intervention on traumatic stress was no longer significant (b = .04, ns), suggesting that changes in avoidant coping completely mediated intervention effects on traumatic stress.

CONCLUSIONS

The LIFT intervention significantly reduced traumatic stress over time, and changes in avoidant coping strategies mediated this effect, suggesting a focus on current stressors and coping skills improvement are important components in addressing traumatic stress for adults living with HIV and CSA.

Prevalence, course, and predictors of emotional distress in pregnant and parenting adolescents

This study examines trajectories and correlates of emotional distress symptoms in pregnant adolescents (n = 203) and nulliparous adolescents (n = 188) from economically disadvantaged communities over an 18-month period. For both groups, the prevalence of significant emotional distress exceeded expectation based on adolescent norms; however, the severity of symptoms did not differ between the 2 groups. Results from growth curve modeling revealed a significant decline in symptoms during the study period for both groups, but pregnant adolescents experienced a different pattern of decline. Also, certain interpersonal factors (e.g., history of physical maltreatment, partner support) appeared to play a more important role in the emotional well-being of pregnant and parenting adolescents relative to nulliparous adolescents. Implications for early identification and intervention are discussed.