Calibration of cosmogenic noble gas production based on ³⁶Cl-³⁶Ar ages. Part 2. The ⁸¹Kr-Kr dating technique

We calibrated the ⁸¹Kr-Kr dating system for ordinary chondrites of different sizes using independent shielding-corrected ³⁶Cl-³⁶Ar ages. Krypton concentrations and isotopic compositions were measured in bulk samples from 14 ordinary chondrites of high petrologic type and the cosmogenic Kr component was obtained by subtracting trapped Kr from phase Q. The thus-determined average cosmogenic ⁷⁸Kr/⁸³Kr, ⁸⁰Kr/⁸³Kr, ⁸²Kr/⁸³Kr, and ⁸4Kr/⁸³Kr ratiC(Lavielle and Marti 1988; Wieler 2002). The cosmogenic ⁷⁸Kr/⁸³Kr ratio is correlated with the cosmogenic 22Ne/21Ne ratio, confirming that ⁷⁸Kr/⁸³Kr is a reliable shielding indicator. Previously, ⁸¹Kr-Kr ages have been determined by assuming the cosmogenic production rate of ⁸¹Kr, P(⁸¹Kr)c, to be 0.95 times the average of the cosmogenic production rates of ⁸⁰Kr and ⁸²Kr; the factor Y = 0.95 therefore accounts for the unequal production of the various Kr isotopes (Marti 1967a). However, Y should be regarded as an empirical adjustment. For samples whose ⁸⁰Kr and ⁸²Kr concentrations may be affected by neutron-capture reactions, the shielding-dependent cosmogenic (⁷⁸Kr/⁸³Kr)c ratio has been used instead to calculate P(⁸¹Kr)/P(⁸³Kr), as for some lunar samples, this ratio has been shown to linearly increase with (⁷⁸Kr/⁸³Kr)c (Marti and Lugmair 1971). However, the ⁸¹Kr-Kr ages of our samples calculated with these methods are on average ~30% higher than their ³⁶Cl-³⁶Ar ages, indicating that most if not all the ⁸¹Kr-Kr ages determined so far are significantly too high. We therefore re-evaluated both methods to determine P(⁸¹Kr)c/P(⁸³Kr)c. Our new Y value of 0.70 ± 0.04 is more than 25% lower than the value of 0.95 used so far. Furthermore, together with literature data, our data indicate that for chondrites, P(⁸¹Kr)c/P(⁸³Kr)c is rather constant at 0.43 ± 0.02, at least for the shielding range covered by our samples ([⁷⁸Kr/⁸³Kr]c = 0.119–0.185; [22Ne/21Ne]c = 1.083–1.144), in contrast to the observations on lunar samples. As expected considering the method used, ⁸¹Kr-Kr ages calculated either directly with this new P(⁸¹Kr)c/P(⁸³Kr)c value or with our new Y value both agree with the corresponding ³⁶Cl-³⁶Ar ages. However, the average deviation of 2% indicates the accuracy of both new ⁸¹Kr-Kr dating methods and the precision of the new dating systems of ~10% is demonstrated by the low scatter in the data. Consequently, this study indicates that the ⁸¹Kr-Kr ages published so far are up to 30% too high.

An assessment of self-concept and violence within a delinquent adolescent population

The purpose of this study was to provide further data on the relationship between self-concept and violence focusing on a delinquent adolescent population. Recent research has explored the relationship between self-concept and violence with most of the research being done with adult populations. Within the literature, there are two opposing views on the question of this relationship. The traditional view supports the idea that low self-esteem is a cause of violent behavior while the non-traditional view supports the idea that high self-esteem may be a contributor to violent behavior. ^ Using a sample of 200 delinquent adolescents 100 of whom had committed acts of violence and 100 who had not, a group comparison study was done which addressed the following questions, (1) within a delinquent population of violent and non-violent adolescents, is there a relationship between violence and self-concept? (2) what is that relationship; (3) using the Piers-Harris Children's Self-Concept Scale, can it be determined that attributes such as behavior, anxiety, popularity, happiness, and physical appearance as they relate to self-concept are more predictive than others in determining who within a delinquent population will commit acts of violence. For the purposes of this study, delinquent adolescents were those who had official records of misconduct with either the school or juvenile authorities. Adolescents classified as violent were those who had committed acts such as assault, use of a weapon, use of deadly force, and sexual assault while adolescents classified as non-violent had committed anti-social acts such as, truancy, talking back and rule breaking. ^ The study concluded that there is a relationship between adolescent violence and self-concept. However, there was insufficient statistical evidence that self-concept is a predictor of violence. ^

Depression, interpersonal violence and lack of social support as barriers to cervical cancer screening among recently immigrated Latinas

Background. Various psychosocial factors have been demonstrated to be barriers for cervical cancer screening among Latinas in the United States, but few studies have researched whether depression and interpersonal violence act as psychosocial barriers to cervical cancer screening. ^ Methods. The proposed study assessed whether depression, interpersonal violence, lack of social support and demographic characteristics such as age, income, education and years in the United States acted as barriers to cervical cancer screening among cantineras in Houston, TX. This secondary data analysis utilized data from a previous cross-sectional study called Project GIRASOL- Community Outreach to Prevent Cervical Cancer among Latinas. The data from the baseline survey (sample size 331) was analyzed using Pearson chi-square and multiple logistic regression. ^ Results. Multiple logistic regression indicates that none and low levels of social support from relatives, depression, and total IPV are significant predictors of non-compliance to cervical cancer screening. ^ Conclusions. Future health interventions or physicians that promote cervical cancer screening among cantineras or recently immigrated Latinas with similar socio-demographic characteristics should try to identify whether Latinas are suffering from depression, interpersonal violence or lack of social support and provide proper referrals to alleviate the problems and positively influence screening behavior. ^

Assessing residents' readiness to screen for domestic violence: Utilizing the transtheoretical model - stages of change, decisional balance and self-efficacy

Domestic violence is a major public health problem, yet most physicians do not effectively identify patients at risk. Medical students and residents are not routinely educated on this topic and little is known about the factors that influence their decisions to include screening for domestic violence in their subsequent practice. In order to assess the readiness of primary care residents to screen all patients for domestic violence, this study utilized a survey incorporating constructs from the Transtheoretical Model, including Stages of Change, Decisional Balance (Pros and Cons) and Self-Efficacy. The survey was distributed to residents at the University of Texas Health Science Center Medical School in Houston in: Internal Medicine, Medicine/Pediatrics, Pediatrics, Family Medicine, and Obstetrics and Gynecology. Data from the survey was analyzed to test the hypothesis that residents in the earlier Stages of Change report more costs and fewer benefits with regards to screening for domestic violence, and that those in the later stages exhibit higher Self-Efficacy scores. The findings from this study were consistent with the model in that benefits to screening (Pros) and Self-Efficacy were correlated with later Stages of Change, however reporting fewer costs (Cons) was not. Very few residents were ready to screen all of their patients.^

Qualitative study: Understanding Mexican American women's experience in intimate partner violence

The purpose of this qualitative study was to gain an understanding of the experiences of Mexican American women living with intimate partner abuse relevant to the process of disclosure of abuse. Limited research exists on the experiences of women who are of Mexican descent living with intimate partner abuse and their disclosure of abuse. Factors that influence disclosure for other populations are well articulated in the literature however, these factors have not been adequately verified in persons of Mexican descent. Data are reported from in-depth interviews with 26 clients at a shelter and an outreach agency in a south Texas-Mexico border community. Semi-structured interview guide was used to elicit information over an 11 month period. A grounded theory ethnography approach was used to analyze data. Verification strategies and constant comparison techniques (e.g. investigator responsiveness, methodological coherence, sampling adequacy, an active analytic stance, and saturation) enhanced rigor of analysis. Nineteen Mexican immigrant women and seven Mexican American women participated in the study. Several themes were discerned related to women's experiences in abuse: painful living, questioning endurance, and confronting reality. In almost every participant's account there was a description of repeated victimization by her intimate partner or partners, and again, by others within and outside her network. The participants discussed several cultural factors (e.g. embarrassment, concerns for family, avoidance of causing pain to family, protection of partner, avoidance of being judged) that hindered their decisions whether or not to disclose. Participants noted that healthcare workers rarely asked probing questions regarding abuse. The timing and process of disclosure took many turns for women in this study. Some of the factors hindering women from disclosing were found to be influenced by cultural practices. The consequences of disclosure for many of the women led them to re-victimization. Implications for practice to avoid missed opportunities with women living in abuse are to: ask questions routinely to encourage disclosure of abuse and offer community resource information for women living in abuse or both.^

A global perspective on intimate partner violence during pregnancy: An analysis of twelve developing countries

Violence against women has been recognized as a significant worldwide human rights issue and public health problem. Women of reproductive age may be particularly at risk, and pregnancy may trigger or escalate violence. Using data available from Demographic and Health Surveys on 271,103 women of reproductive age (15-49) from Bolivia, Cameroon, Colombia, Dominican Republic, Egypt, Haiti, India, Kenya, Nicaragua, Peru, South Africa, and Zambia, this study examined the nature of domestic violence during pregnancy in developing countries, including prevalence, demographic and risk factors, maternal and child health outcomes, perpetrators of violence, help-seeking behavior, and social support. In the majority of countries analyzed, violence during pregnancy consistently occurred at approximately one-third the rate at which domestic violence occurred overall. Younger women and women with more children were particularly at risk. Abuse during pregnancy was significantly associated with history of a terminated pregnancy and under-5 child mortality in most countries, and with neonatal and post-neonatal mortality in most Latin American countries. Women who were abused during pregnancy were most often abused by their current or former husband or boyfriend and most never attempted to seek help. In most countries that examined social support, women abused during pregnancy had significantly less contact with family and friends. Implications for practice and research are discussed. ^

Is sexual violence associated with symptoms of depression and suicide attempts

Sexual assault, depression, and suicide are all very serious issues among youth today. This study sought to quantify the association between sexual violence, symptoms of depression, and suicide attempts through the use of 2007 Youth Risk Behavior Survey (YRBS) data. The YRBS is a nationally representative dataset of United States high school students, grades 9-12. It was hypothesized that sexual violence is significantly associated with symptoms of depression and suicide attempts. Through multivariate logistic regression, it was determined that students who had ever experienced forced sex were 3.10 (2.7-3.6) times as likely to be depressed, in the past 12 months, and 4.22 (3.5-5.1) times as likely to have attempted suicide. Female victims were 3.43 (2.9-4.0) times as likely to be depressed; male victims were 5.40 (3.7-7.9) times as likely to have attempted suicide. Sexual violence is significantly associated with both symptoms of depression and suicide attempt when stratified by gender, grade, and race/ethnicity. These results indicate that further study of the association between sexual violence and symptoms of depression and suicide attempts need to be conducted in order to establish temporality.^

Pregnancy intention, intimate partner violence, and the use of prenatal care in Jordan

Previous research has suggested an association between intimate partner violence and pregnancy intention status, and pregnancy intention status and the use of prenatal care services, however much of these studies have been conducted in high income countries (HIC) rather than low and middle income countries (LMIC). The objectives of this study were to examine the relationship between pregnancy intention status and intimate partner violence, and pregnancy intention status and the use of prenatal care among ever-married women in Jordan.^ Data were collected from a nationally representative sample of women interviewed in the 2007 Jordan Demographic and Health Survey. The sample was restricted to ever-married women, 15–49 years of age, who had a live birth within the five years preceding the survey. Multivariate logistic regression analyses was used to determine the relationship between intimate partner violence and pregnancy intention status, and pregnancy intention status and the use of prenatal care services.^ Women who reported a mistimed pregnancy (PORadj 1.96, 95% CI: 1.31–2.95), as well as an unwanted pregnancy (PORadj 1.32, 95% CI: 0.80–2.18) had a higher odds of experiencing lifetime physical and/or sexual abuse compared with women reporting a wanted pregnancy. Women not initiating prenatal care by the end of the first trimester had statistically significant higher odds of reporting both a mistimed (PORadj 2.07, 95% CI: 1.55–2.77) and unwanted pregnancy (PORadj 2.36, 95% CI: 1.68–3.31), compared with women initiating care in the first trimester. Additionally, women not receiving the adequate number of prenatal care visits for their last pregnancy had a higher odds of reporting an unwanted pregnancy (PORadj 2.11, 95% CI: 1.35–3.29) and mistimed pregnancy (POR adj 1.41, 95% CI: 0.96–2.07).^ Reducing intimate partner violence may decrease the prevalence of mistimed or unwanted pregnancies, and reducing both unwanted and mistimed pregnancies may decrease the prevalence of women not receiving timely and adequate prenatal care among women in this population. Further research, particularly in LMIC, is needed regarding the determinants of unintended pregnancy and its association with intimate partner violence as well as with the use of prenatal care services. ^

A study of factors influencing high school students' attitudes and opinions about violence

Tenth grade students in a lower income neighborhood Houston school were surveyed on violence related beliefs, attitudes, and coping ability. Self-administered questionnaires were used to collect information for scale scores for statistical analysis.^ One hundred twenty six students participated of which 60% were Hispanic, 18% Black, 18% White, 2 American Indians, and 3 Asian/Pacific persons. There were 60 males, mean age 16.03, and 66 females, mean age 15.49. One-half of the sample reported repeating a grade, 53.4% of males, and 47% of females. Females' self-reported grades were slightly higher than males.^ Measures of student acceptance of violence and ability to handle conflict peacefully were studied in relation to student responses to questions about five areas: parental monitoring of the student, parent type of punishment, optimism about future prospects, frustration tolerance, and perceived peer group attitudes and practices.^ Significant gender differences included males having higher violence acceptance scores and females higher on coping with conflict peacefully. No significant race differences or gender interactions were found.^ Females' scores on future orientation were inversely related to their scores on the measure of acceptance of violence. For males, parents' punishment and perceived peer attitudes were positively related to their acceptance of violence, p $<$.0083.^ Female handling of conflict was significantly related to frustration tolerance and optimism; not significant were perceived peer attitudes, parent monitoring or punishment method. For males significantly related to handling conflict were perceived peer attitudes, parental monitoring, and severity of punishment, with the last two terms having a significant interaction effect, and inversely correlated (less monitoring, harsher punishment explained lower ability to handle conflict). ^

Associations between exposure to violence and depression in 5th grade students: Results from the Healthy Passages study

Purpose. To describe the prevalence of violence exposure and depression and their association among 5th grade students. ^ Methods.. Students (n=5,147) attending 5th grade (mean age 11.12) from three major metropolitan areas in the United States were surveyed on various health-related measures including experience with being a victim of violence (adapted from YRBS and Traumatic Events Screening Inventory) and depressive symptoms (from the DISC Predictive Scale). Prevalence was calculated for rates of violence exposure as well as depression defined as having five or more depressive symptoms. Logistic regression was used to examine the association between exposure to violence and depression. ^ Results. This study found that over 35% of students were exposed to some form of violence such as being threatened, hit, punched, kicked, beaten up, or threatened/injured with a gun or knife. Male students had a higher prevalence than female students on almost all exposure types. Over 7% of students also reported having 5 or more depressive symptoms. All forms of violence were significantly associated with depression. Students who had been a victim of violence were between 2.5 and 6.5 more likely to have five or more depression symptoms. Conslusion. The results of this study underscore the urgent need of collaborative prevention and treatment efforts for children exposed to violence. By preventing such exposure, serious effects including physical injury, mental health problems, and other detrimental outcomes may be mitigated.^

Domestic Violence Resources for Women Receiving Intensive Family Preservation Services

Intimate partner violence is a common correlate of child abuse and neglect and often is not addressed in family preservation services. In many cases, the ideologies of family preservationists and advocates for women 's safety can be at odds. This article presents a study of a collaborative model of intervention, utilizing family preservation workers and community resource practitioners working with domestic violence as group facilitators. The study utilizes a pretest, post-test design to evaluate a domestic violence resource group for women who were concurrently receiving intensive family preservation services. The study examines the effect of the program on participants' self-perceptions regarding self-esteem, independence, goals, social isolation, and assertiveness. Caseworker perceptions of client characteristics also are evaluated, and qualitative responses of the effects of the program are included.

(Supplement Table S2) Results of 230Th/U-dating

We compared the suitability of two skeletal materials of the Atlantic brain coral Diploria strigosa for 230Th/U-dating: the commonly used bulk material comprising all skeletal elements and the denser theca wall material. Eight fossil corals of presumably Last Interglacial age from Bonaire, southern Caribbean Sea, were investigated, and several sub-samples were dated from each coral. For four corals, both the ages and the activity ratios of the bulk material and theca wall agree within uncertainty. Three corals show significantly older ages for their bulk material than for their theca wall material as well as substantially elevated 232Th content and (230Th/238U) ratios. The bulk material samples of another coral show younger ages and lower (230Th/238U) ratios than the corresponding theca wall samples. This coral also contains a considerable amount of 232Th. The application of the available open-system models developed to account for post-depositional diagenetic effects in corals shows that none of the models can successfully be applied to the Bonaire corals. The most likely explanation for this observation is that the assumptions of the models are not fulfilled by our data set. Comparison of the theca wall and bulk material data enables us to obtain information about the open-system processes that affected the corals. The corals showing apparently older ages for their bulk material were probably affected by contamination with a secondary (detrital) phase. The most likely source of the detrital material is carbonate sand. The higher (230Th/232Th) ratio of this material implies that detrital contamination would have a much stronger impact on the ages than a contaminant with a bulk Earth (230Th/232Th) ratio and that the threshold for the commonly applied 232Th reliability criterion would be much lower than the generally used value of 1 ng g^-1. The coral showing apparently younger ages for its bulk material was probably influenced by more than one diagenetic process. A potential scenario is a combination of detrital contamination and U addition by secondary pore infillings. Our results show that the dense theca wall material of D. strigosa is generally less affected by post-depositional open-system behaviour and better suited for 230Th/U-dating than the bulk material. This is also obvious from the fact that all ages of theca wall material reflect a Last Interglacial origin (~125 ka), whereas the bulk material samples are either substantially older or younger. However, for some corals, the 230Th/U-ages and activity ratios of the bulk material and the theca wall samples are similar. This shows that strictly reliable 230Th/U-ages can also be obtained from bulk material samples of exceptionally well-preserved corals. However, the bulk material samples more frequently show elevated activity ratios and ages than the corresponding theca wall samples. Our findings should be generally applicable to brain corals (Mussidae) that are found in tropical oceans worldwide and may enable reliable 230Th/U-dating of fossil corals with similar skeletal architecture, even if their bulk skeleton is altered by diagenesis. The 230Th/U-ages we consider reliable (120-130 ka), along with a recently published age of 118 ka, provide the first comprehensive dating of the elevated lower reef terrace at Bonaire (118-130 ka), which is in agreement in timing and duration with other Last Interglacial records.