995 research outputs found

    The Chemical Evolution of Helium in Globular Clusters: Implications for the Self-Pollution Scenario

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    We investigate the suggestion that there are stellar populations in some globular clusters with enhanced helium (Y from 0.28 to 0.40) compared to the primordial value. We assume that a previous generation of massive Asymptotic Giant Branch (AGB) stars have polluted the cluster. Two independent sets of AGB yields are used to follow the evolution of helium and CNO using a Salpeter initial mass function (IMF) and two top-heavy IMFs. In no case are we able to produce the postulated large Y ~ 0.35 without violating the observational constraint that the CNO content is nearly constant.Comment: accepted for publication in Ap

    Multiple stellar populations and their influence on blue stragglers

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    It has become clear in recent years that globular clusters are not simple stellar populations, but may host chemically distinct sub-populations, typically with an enhanced helium abundance. These helium-rich populations can make up a substantial fraction of all cluster stars. One of the proposed formation channels for blue straggler stars is the physical collision and merger of two stars. In the context of multiple populations, collisions between stars with different helium abundances should occur and contribute to the observed blue straggler population. This will affect the predicted blue straggler colour and luminosity function. We quantify this effect by calculating models of mergers resulting from collisions between stars with different helium abundances and using these models to model a merger population. We then compare these results to four observed clusters, NGC 1851, NGC 2808, NGC 5634 and NGC 6093. As in previous studies our models deviate from the observations, particularly in the colour distributions. However, our results are consistent with observations of multiple populations in these clusters. In NGC 2808, our best fitting models include normal and helium enhanced populations, in agreement with helium enhancement inferred in this cluster. The other three clusters show better agreement with models that do not include helium enhancement. We discuss future prospects to improve the modelling of blue straggler populations and the role that the models we present here can play in such a study.Comment: 10 pages, 7 figures, 6 tables Accepted for publication in MNRAS, 15 June 201

    Attention Deficit Hyperactivity Disorder and Risk of Posttraumatic Stress and Related Disorders: A Prospective Longitudinal Evaluation in U.S. Army Soldiers

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    Crossâ sectional associations between attention deficit hyperactivity disorder (ADHD) and posttraumatic stress disorder (PTSD) have been observed, but longitudinal studies assessing this association are lacking. This prospective study evaluated the association between predeployment ADHD and postdeployment PTSD among U.S. Army soldiers. Soldiers who deployed to Afghanistan were surveyed before deployment (T0) and approximately 1 month (T1), 3 months (T2), and 9 months (T3) after their return. Logistic regression was performed to estimate the association between predeployment ADHD and postdeployment (T2 or T3) PTSD among 4,612 soldiers with data at all waves and no record of stimulant medication treatment during the study. To evaluate specificity of the ADHDâ PTSD association, we examined associations among predeployment ADHD, postdeployment major depressive episode (MDE), generalized anxiety disorder (GAD), and suicidal ideation. Weighted prevalence of ADHD predeployment was 6.1% (SE = 0.4%). Adjusting for other risk factors, predeployment ADHD was associated with risk of postdeployment PTSD, adjusted odds ratio (AOR) = 2.13, 95% CI [1.51, 3.00], p < .001, including incidence among soldiers with no predeployment history of PTSD, AOR = 2.50, 95% CI [1.69, 3.69], p < .001. ADHD was associated with postdeployment MDE, AOR = 2.80, 95% CI [2.01, 3.91], p < .001, and GAD, AOR = 3.04, 95% CI [2.10, 4.42], p < .001, but not suicidal ideation. Recognition of associations between predeployment ADHD and postdeployment PTSD, MDE, and GAD may inform targeted prevention efforts. Future research should examine whether treatment of ADHD is protective against PTSD and related disorders in traumaâ exposed individuals.ResumenSpanish Abstracts by Asociación Chilena de Estrés Traumático (ACET)El trastorno de déficit atencional con hiperactividad y el riesgo del trastorno de estrés postraumático y trastornos relacionados: Una evaluación longitudinal prospectiva en soldados del ejército estadounidenseTDAH Y RIESGO DE TEPT EN SOLDADOS DEL EJà RCITO DE EE.UU.Se han observado asociaciones transversales entre el trastorno por déficit de atención con hiperactividad (TDAH) y el trastorno por estrés postraumático (TEPT), pero faltan estudios longitudinales que evalúen esta asociación. Este estudio prospectivo evaluó la asociación entre el TDAH previo al despliegue y el TEPT posterior al despliegue entre los soldados del Ejército de Estados Unidos. Los soldados desplegados en Afganistán fueron encuestados antes del despliegue (T0) y aproximadamente 1 mes (T1), 3 meses (T2), y 9 meses (T3) después de su regreso del despliegue. Se realizó una regresión logística para estimar la asociación entre el TDAH previo al despliegue y el TEPT posterior al despliegue (T2 o T3) en 4.612 soldados con datos en todas las etapas y sin registro de tratamiento con medicamentos estimulantes durante el estudio. Para evaluar la especificidad de la asociación TDAHâ TEPT, examinamos las asociaciones entre el TDAH previo al despliegue, el episodio depresivo mayor posterior al despliegue (EDM), el trastorno de ansiedad generalizada (TAG), y la ideación suicida. La prevalencia ponderada del TDAH previo al despliegue fue de 6.1% (SE = 0.4%). Al controlar los otros factores de riesgo, el TDAH previo al despliegue se asoció con el riesgo de TEPT posterior al despliegue, odds ratio ajustado (AOR en su sigla en inglés) = 2.13, IC del 95% [1.51, 3.00], p <.001, incluida la incidencia entre soldados sin historial previo al despliegue de TEPT, AOR = 2.50, IC del 95% [1.69, 3.69], p <.001. El TDAH se asoció con el EDM posterior al despliegue, AOR = 2.80, IC del 95% [2.01, 3.91], p <.001, y TAG, AOR = 3.04, IC del 95% [2.10, 4.42], p <.001, pero no con ideación suicida. El reconocimiento de las asociaciones entre el TDAH previo al despliegue y el TEPT, el EDM, y el TAG posterior al despliegue puede informar los esfuerzos de prevención específicos. Las investigaciones futuras deberían examinar si el tratamiento del TDAH protege contra el TEPT y los trastornos relacionados en personas expuestas a trauma.æ ½è±¡Traditional and Simplified Chinese Abstracts by the Asian Society for Traumatic Stress Studies (AsianSTSS)ç°¡é« å ç¹ é« ä¸­æ æ ®è¦ ç ±äº æ´²å µå ·å¿ ç ç  ç©¶å­¸æ 翻譯Attention Deficit Hyperactivity Disorder and Risk of Posttraumatic Stress and Related Disorders: A Prospective Longitudinal Evaluation in US Army SoldiersTraditional Chineseæ¨ é¡ : å° æ³¨å ä¸ è¶³æ é åº¦æ´»èº ç è æ £å µå ·å¾ å£ å ç å ç ¸é ç ¾ç ç é¢¨é ª:å° ç¾ å è» äººé ²è¡ ç å ç »ç¸±è²«ç  ç©¶æ ®è¦ : é å¾ ä¸ ç ´æ ç  ç©¶æª¢è¦ å° æ³¨å ä¸ è¶³æ é åº¦æ´»èº ç (ADHD)è å µå ·å¾ å£ å ç (PTSD)ä¹ é ç æ©«æ ·æ §é é £, å ¯æ ¯, æ å ä» æ¬ ç¼ºæª¢è¦ å ©è é é £ç ç¸±è²«ç  ç©¶ã æ ¬å ç »ç  ç©¶æ ¨å ¨é é ç¾ è» æ¨£æ ¬, è© ä¼°æ å½¹å ADHDè· æ å½¹å¾ PTSDç é é £ã æ¨£æ ¬ç ºå å¾ é ¿å¯ æ± æ å½¹ç è» äºº, å ¨æ å½¹å (T0)å å® æ æ å½¹å¾ ç´ 1å æ (T1)ã 3å æ (T2)å 9å æ (T3)æ ¥å èª¿æ ¥ã æ å 以é 輯迴歸å æ å æ æ 波段ç æ ¸æ , ä¼°è¨ 4,612å è» äººæ å½¹å ADHDè· æ å½¹å¾ (T2 æ T3)PTSDç é é £ã ç  ç©¶ä¸­, æ¨£æ ¬ä¸¦ç ¡æ ç ¨è å¥®è ¥ç ©ã ç ºäº è§£ADHDâ PTSDç ç ¹æ® é é £, æ å æª¢è¦ ä»¥ä¸ é  ç ®ä¹ é ç é é £:æ å½¹å ADHDã å® æ æ å½¹å¾ ç å ´é æ é¬±ç¯ æ®µ(MDE)ã å»£æ³ æ §ç ¦æ ®ç (GAD)ã è ªæ®ºæ 念ã æ å½¹å ADHDæ ®é åº¦ç º6.1% (SE = 0.4%)ã å° å ¶ä» é¢¨é ªå  ç´ ä½ èª¿ç¯ å¾ , æ å½¹å ADHDè· æ å½¹å¾ æ £PTSDç é¢¨é ªæ æ é é £(å·²èª¿ç¯ å ç® æ¯ (AOR) = 2.13, 95% CI [1.51, 3.00], p < .001), ç ¶ä¸­å æ ¬æ å½¹å ä¸¦ç ¡PTSDç è» äºº(AOR = 2.50, 95% CI [1.69, 3.69], p < .001)ã ADHDè· å® æ æ å½¹å¾ æ £MDEç (AOR = 2.80, 95% CI [2.01, 3.91], p < .001)å GAD(AOR = 3.04, 95% CI [2.10, 4.42] p < .001)é ½æ é , ä½ è· è ªæ®ºæ å¿µç ¡é ã äº è§£æ å½¹å ADHDè· æ å½¹å¾ PTSDã MDEå GADç é é £, å ¯è ½æ å ©ç ¼å± é å° æ §ç é  é ²å·¥ä½ ã æ ªä¾ ç  ç©¶æ æª¢è¦ å° å å µäººå£«æ ä¾ ADHDæ²»ç , æ ¯å ¦å° å ¶PTSDå ç ¸é ç ¾ç æ ä¿ è­·æ æ ã Simplified Chineseæ  é¢ : ä¸ æ³¨å ä¸ è¶³æ è¿ åº¦æ´»è· ç ä¸ æ £å 伤å å å ç å ç ¸å ³ç ¾ç ç é£ é ©:å¯¹ç¾ å ½å äººè¿ è¡ ç å ç »çºµè´¯ç  ç©¶æ ®è¦ : è¿ å¾ ä¸ ç ´æ ç  ç©¶æ£ è§ ä¸ æ³¨å ä¸ è¶³æ è¿ åº¦æ´»è· ç (ADHD)ä¸ å 伤å å å ç (PTSD)ä¹ é ´ç æ¨ªæ ­æ §å ³è¿ , å ¯æ ¯, æ ä»¬ä» æ¬ ç¼ºæ£ è§ ä¸¤è å ³è¿ ç çºµè´¯ç  ç©¶ã æ ¬å ç »ç  ç©¶æ ¨å ¨é è¿ ç¾ å æ ·æ ¬, è¯ ä¼°æ å½¹å ADHDè· æ å½¹å PTSDç å ³è¿ ã æ ·æ ¬ä¸ºå å¾ é ¿å¯ æ± æ å½¹ç å 人, å ¨æ å½¹å (T0)å å® æ æ å½¹å 约1个æ (T1)ã 3个æ (T2)å 9个æ (T3)æ ¥å è° æ ¥ã æ ä»¬ä»¥é »è¾ å å½ å æ å æ æ 波段ç æ °æ ®, 估计4,612å å 人æ å½¹å ADHDè· æ å½¹å (T2 æ T3)PTSDç å ³è¿ ã ç  ç©¶ä¸­, æ ·æ ¬å¹¶æ  æ ç ¨å ´å¥ è ¯ç ©ã ä¸ºäº è§£ADHDâ PTSDç ç ¹æ® å ³è¿ , æ ä»¬æ£ è§ ä»¥ä¸ é¡¹ç ®ä¹ é ´ç å ³è¿ :æ å½¹å ADHDã å® æ æ å½¹å ç 严é æ é è 段(MDE)ã å¹¿æ³ æ §ç ¦è ç (GAD)ã è ªæ æ 念ã æ å½¹å ADHDæ ®é 度为6.1% (SE = 0.4%)ã å¯¹å ¶ä» é£ é ©å  ç´ ä½ è° è å , æ å½¹å ADHDè· æ å½¹å æ £PTSDç é£ é ©æ æ å ³è¿ (å·²è° è è ç® æ¯ (AOR) = 2.13, 95% CI [1.51, 3.00], p < .001), å½ ä¸­å æ ¬æ å½¹å å¹¶æ  PTSDç å 人(AOR = 2.50, 95% CI [1.69, 3.69], p < .001)ã ADHDè· å® æ æ å½¹å æ £MDEç (AOR = 2.80, 95% CI [2.01, 3.91], p < .001)å GAD(AOR = 3.04, 95% CI [2.10, 4.42] p < .001)é ½æ å ³, ä½ è· è ªæ æ å¿µæ  å ³ã äº è§£æ å½¹å ADHDè· æ å½¹å PTSDã MDEå GADç å ³è¿ , å ¯è ½æ å ©å å± é å¯¹æ §ç é¢ é ²å·¥ä½ ã æ ªæ ¥ç  ç©¶åº æ£ è§ å¯¹å å 人士æ ä¾ ADHDæ²»ç , æ ¯å ¦å¯¹å ¶PTSDå ç ¸å ³ç ¾ç æ ä¿ æ ¤æ åº ãPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146971/1/jts22347_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146971/2/jts22347.pd

    How can Psychology inform disaster research?

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    This paper will set out our current understanding of how psychology can help us to understand and influence preparation for, and responses to disaster. Using four primary research studies, this paper will outline how psychology can inform our knowledge of all stages of a disaster (preparedness, immediate response and long-term consequences). The first study used a questionnaire design to examine factors that influence evacuation behaviours. The second and third studies explored physiological and psychological responses to simulated disaster training. The fourth study explored the consequences of trauma exposure focusing specifically on predictors of post-traumatic stress disorder and post-traumatic growth. The results show that psychology can play a role in our understanding of human behaviour during a disaster. Specifically, study one shows how psychology can inform disaster preparation by identifying barriers to evacuation. The second and third studies show how psychology can help us to explore and predict human behaviour during a disaster. Finally, the fourth study highlights how psychology can help us to understand the longer-term impact of exposure to traumatic events. Overall, the results of these studies show that psychological knowledge can predict and positively influence human behaviour in response to disasters

    Appl Environ Microbiol

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    Understanding the mechanisms behind the typicity of regional wines inevitably brings attention to microorganisms associated with their production. Oenococcus oeni is the main bacterial species involved in wine and cider making. It develops after the yeast-driven alcoholic fermentation and performs the malolactic fermentation, which improves the taste and aromatic complexity of most wines. Here, we have evaluated the diversity and specificity of O. oeni strains in six regions. A total of 235 wines and ciders were collected during spontaneous malolactic fermentations and used to isolate 3,212 bacterial colonies. They were typed by multilocus variable analysis, which disclosed a total of 514 O. oeni strains. Their phylogenetic relationships were evaluated by a second typing method based on single nucleotide polymorphism (SNP) analysis. Taken together, the results indicate that each region holds a high diversity of strains that constitute a unique population. However, strains present in each region belong to diverse phylogenetic groups, and the same groups can be detected in different regions, indicating that strains are not genetically adapted to regions. In contrast, greater strain identity was seen for cider, white wine, or red wine of Burgundy, suggesting that genetic adaptation to these products occurred. This study reports the isolation, genotyping, and geographic distribution analysis of the largest collection of O. oeni strains performed to date. It reveals that there is very high diversity of strains in each region, the majority of them being detected in a single region. The study also reports the development of an SNP genotyping method that is useful for analyzing the distribution of O. oeni phylogroups. The results show that strains are not genetically adapted to regions but to specific types of wines. They reveal new phylogroups of strains, particularly two phylogroups associated with white wines and red wines of Burgundy. Taken together, the results shed light on the diversity and specificity of wild strains of O. oeni, which is crucial for understanding their real contribution to the unique properties of wines.Multi-strain indigenous Yeast and Bacterial starters for ‘Wild-ferment’ Wine productio

    Predictive validity and correlates of selfâ assessed resilience among U.S. Army soldiers

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142339/1/da22694.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142339/2/da22694_am.pd

    Early career resilience: interdisciplinary insights to support professional education of Radiation Therapists

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    Background : A number of studies across a range of countries have indicated a proportion of the radiotherapy workforce maybe experiencing burnout. Furthermore, current national attrition from UK radiotherapy training programmes is approximately 36%. The consequence is a potential shortfall in qualifying practitioners. The loss of skilled practitioners from the workplace through burnout and a reduction in the numbers qualifying at a time of rising cancer referrals has implications on the ability of radiotherapy services to keep pace with demand. A report from the College of Radiographers on the factors affecting attrition from UK training programmes recommends the development of emotional resilience as part of the educational preparation for Therapists, but failed to identify specific interventions that may help. Radiation Therapists (RTTs) are not unique in terms of their exposure to the potential of burnout and other professionals share similar concerns. In this paper we report on an interdisciplinary study of professional resilience, which indicates that there is much we can learn from other professions that are engaged in emotional labour. The concept of ‘resilience’ is important in retention studies but research in this field is limited by a lack of detailed accounts of resilience in specific professional contexts; with few accounts of strategies in professional education to develop resilience. Aim : To identify: what supports and hinders the development of professional resilience in early career professionals, in professions involving emotional and moral challenge, such as radiation therapy; what creative pedagogical approaches may help to develop resilience. Method : Using a mixed method design over 50 participants were invited to participate from radiotherapy, social work and teacher education. A combination of survey research, interpretative interviews and innovative group activities were used across four key groups; early career professionals, current students, Higher Education lecturers and work based professionals who support students. Purposive sampling was undertaken with codes, themes and texts used iteratively to develop understanding of professional resilience. Coding was informed by principles of constructivist grounded theory to allow for the identification of themes. Peer debriefing was used to agree the coding structure and member checking was used to confirm identified themes with research participants. Results : Emergent themes indicate resilience is dependent on a complex interplay between individual and organisational (or situated) characteristics. Key concepts were: Transitions- new identity demands Organisational and systemic issues- being treated unfairly, team culture, difficult cases, feedback and support, professional demands Personal Characteristics – personal actions, personal qualities (accepting, confidence, forms of reflection, interpersonal skills and positive psychology) Professionality- agency, commitment, moral purpose and value Conclusion : By addressing issues of resilience course credibility is enhanced as a preparation for professional life; with a subsequent corollary of reduced attrition. The data from this study can be used to inform a creative curriculum to enhance professional resilience in students and early career professionals.</p

    Defining and characterizing team resilience in elite sport

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    Objectives: The objectives of this study were to develop a definition of team resilience and to identify the resilient characteristics of elite sport teams. Design and Method: Focus groups consisting of a total of 31 participants were conducted with five elite teams from a range of sports. An interpretive thematic analysis using inductive and deductive reasoning was employed to analyze the data. Results and Conclusions: Team resilience was defined as a dynamic, psychosocial process which protects a group of individuals from the potential negative effect of the stressors they collectively encounter. It comprises of processes whereby team members use their individual and combined resources to positively adapt when experiencing adversity. Findings revealed four main resilient characteristics of elite sport teams: group structure, mastery approaches, social capital, and collective efficacy. This study extends resilience research in sport psychology by providing greater conceptual clarity of resilience at a team level. The implications of the findings for those conducting research in this area and for those consulting with elite sport teams are discussed

    Alcohol Misuse and Coâ Occurring Mental Disorders Among New Soldiers in the U.S. Army

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135492/1/acer13269_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135492/2/acer13269.pd
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