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1.
PLoS One ; 19(10): e0311256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39352883

RESUMO

BACKGROUND: Patients admitted to hospitals after emergency care for injury or acute illness are at risk for later mental health problems. The American College of Surgeons Committee on Trauma Standards for care of injured patients call for mental health risk screening, and the Hospital Mental Health Risk Screen (HMHRS) accurately identified at-risk patients in a developmental study that included patients from five ethnoracial groups. Replication of these findings is essential, because initial positive results for predictive screens can fail to replicate if the items were strongly related to outcomes in the development sample but not in a new sample from the population the screen was intended for. STUDY DESIGN: Replication of the predictive performance of the 10-item HMHRS was studied prospectively in ethnoracially diverse patients admitted after emergency care for acute illness or injury in three hospitals across the U.S. RESULTS: Risk screen scores and follow-up mental health outcomes were obtained for 452 of 631 patients enrolled (72%). A cut score of 10 on the HMHRS correctly identified 79% of the patients who reported elevated levels of depression, anxiety, and PTSD symptoms two months post-admission (sensitivity) and 72% of the patients whose symptoms were not elevated (specificity). HMHRS scores also predicted well for patients with acute illness, for patients with injuries, and for patients who reported an Asian American/Pacific Islander, Black, Latinx, Multirace, or White identity. CONCLUSIONS: Predictive performance of the HMHRS was strong overall and within all five ethnoracial subgroups. Routine screening could reduce suffering and health care costs, increase health and mental health equity, and foster preventive care research and implementation. The performance of the HMHRS should be studied in other countries and in other populations of recent trauma survivors, such as survivors of disaster or mass violence.


Assuntos
Saúde Mental , Humanos , Masculino , Feminino , Adulto , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Programas de Rastreamento , Medição de Risco , Adulto Jovem , Adolescente , Serviço Hospitalar de Emergência , Idoso , Estudos Prospectivos , Serviços Médicos de Emergência
2.
J Health Care Poor Underserved ; 35(3): 903-919, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39129609

RESUMO

Research has established relationships between social determinants of health (SDOH) and mental health, with mixed findings on which ethnoracial groups are most vulnerable to deleterious outcomes. The current study examines ethnoracial differences in SDOH and their associations with acute mental health symptoms among patients hospitalized after emergency care. Using data collected in a multi-site study of 1,318 diverse adults admitted to inpatient units, we performed analyses using linear regression models. Findings show that Multiracial/Indigenous and Black adults had significantly higher discrimination and financial stress scores. However, compared with White adults, the positive association between extreme discrimination and acute mental health symptoms was diminished among Latinx (B=-2.3; p=.02) and Black individuals (B=-1.6; p=.05) as was the positive association between financial insecurity and acute mental health symptoms for Black adults (B=-2.3; p=.04). This study provides evidence of differential experiences of SDOH and mental health challenges that may warrant tailored interventions.


Assuntos
Determinantes Sociais da Saúde , Humanos , Determinantes Sociais da Saúde/etnologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Hospitalização/estatística & dados numéricos , Negro ou Afro-Americano/estatística & dados numéricos , Negro ou Afro-Americano/psicologia , Transtornos Mentais/etnologia , Estresse Financeiro/etnologia , Estresse Financeiro/psicologia , Hispânico ou Latino/psicologia , Hispânico ou Latino/estatística & dados numéricos , População Branca/estatística & dados numéricos , População Branca/psicologia , Saúde Mental/etnologia , Adulto Jovem , Etnicidade/estatística & dados numéricos , Etnicidade/psicologia , Idoso , Estados Unidos/epidemiologia
3.
Science ; 383(6685): 898-903, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38386759

RESUMO

The nearby Supernova 1987A was accompanied by a burst of neutrino emission, which indicates that a compact object (a neutron star or black hole) was formed in the explosion. There has been no direct observation of this compact object. In this work, we observe the supernova remnant with JWST spectroscopy, finding narrow infrared emission lines of argon and sulfur. The line emission is spatially unresolved and blueshifted in velocity relative to the supernova rest frame. We interpret the lines as gas illuminated by a source of ionizing photons located close to the center of the expanding ejecta. Photoionization models show that the line ratios are consistent with ionization by a cooling neutron star or a pulsar wind nebula. The velocity shift could be evidence for a neutron star natal kick.

4.
J Am Coll Surg ; 238(2): 147-156, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038350

RESUMO

BACKGROUND: Patients hospitalized after emergency care are at risk for later mental health problems such as depression, anxiety, and posttraumatic stress disorder symptoms. The American College of Surgeons Committee on Trauma standards for verification require Level I and II trauma centers to screen patients at high risk for mental health problems. This study aimed to develop and examine the performance of a novel mental health risk screen for hospitalized patients based on samples that reflect the diversity of the US population. STUDY DESIGN: We studied patients admitted after emergency care to 3 hospitals that serve ethnically, racially, and socioeconomically diverse populations. We assessed risk factors during hospitalization and mental health symptoms at follow-up. We conducted analyses to identify the most predictive risk factors, selected items to assess each risk, and determined the fewest items needed to predict mental health symptoms at follow-up. Analyses were conducted for the entire sample and within 5 ethnic and racial subgroups. RESULTS: Among 1,320 patients, 10 items accurately identified 75% of patients who later had elevated levels of mental health symptoms and 71% of those who did not. Screen performance was good to excellent within each of the ethnic and racial groups studied. CONCLUSIONS: The Hospital Mental Health Risk Screen accurately predicted mental health outcomes overall and within ethnic and racial subgroups. If performance is replicated in a new sample, the screen could be used to screen patients hospitalized after emergency care for mental health risk. Routine screening could increase health and mental health equity and foster preventive care research and implementation.


Assuntos
Saúde Mental , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/etiologia , Centros de Traumatologia , Hospitalização , Hospitais
5.
PLoS One ; 18(9): e0286563, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37729187

RESUMO

BACKGROUND: High rates of mental health symptoms such as depression, anxiety, and posttraumatic stress disorder (PTSD) have been found in patients hospitalized with traumatic injuries, but little is known about these problems in patients hospitalized with acute illnesses. A similarly high prevalence of mental health problems in patients hospitalized with acute illness would have significant public health implications because acute illness and injury are both common, and mental health problems of depression, anxiety, and PTSD are highly debilitating. METHODS AND FINDINGS: In patients admitted after emergency care for Acute Illness (N = 656) or Injury (N = 661) to three hospitals across the United States, symptoms of depression, anxiety, and posttraumatic stress were compared acutely (Acute Stress Disorder) and two months post-admission (PTSD). Patients were ethnically/racially diverse and 54% female. No differences were found between the Acute Illness and Injury groups in levels of any symptoms acutely or two months post-admission. At two months post-admission, at least one symptom type was elevated for 37% of the Acute Illness group and 39% of the Injury group. Within racial/ethnic groups, PTSD symptoms were higher in Black patients with injuries than for Black patients with acute illness. A disproportionate number of Black patients had been assaulted. CONCLUSIONS: This study found comparable levels of mental health sequelae in patients hospitalized after emergency care for acute illness as in patients hospitalized after emergency care for injury. Findings of significantly higher symptoms and interpersonal violence injuries in Black patients with injury suggest that there may be important and actionable differences in mental health sequelae across ethnic/racial identities and/or mechanisms of injury or illness. Routine screening for mental health risk for all patients admitted after emergency care could foster preventive care and reduce ethnic/racial disparities in mental health responses to acute illness or injury.


Assuntos
Saúde Mental , Transtornos de Estresse Pós-Traumáticos , Humanos , Feminino , Masculino , Doença Aguda , Transtornos de Ansiedade , Ansiedade/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Progressão da Doença
6.
Psychol Med ; 53(11): 5099-5108, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35903010

RESUMO

BACKGROUND: Racial/ethnic differences in mental health outcomes after a traumatic event have been reported. Less is known about factors that explain these differences. We examined whether pre-, peri-, and post-trauma risk factors explained racial/ethnic differences in acute and longer-term posttraumatic stress disorder (PTSD), depression, and anxiety symptoms in patients hospitalized following traumatic injury or illness. METHODS: PTSD, depression, and anxiety symptoms were assessed during hospitalization and 2 and 6 months later among 1310 adult patients (6.95% Asian, 14.96% Latinx, 23.66% Black, 4.58% multiracial, and 49.85% White). Individual growth curve models examined racial/ethnic differences in PTSD, depression, and anxiety symptoms at each time point and in their rate of change over time, and whether pre-, peri-, and post-trauma risk factors explained these differences. RESULTS: Latinx, Black, and multiracial patients had higher acute PTSD symptoms than White patients, which remained higher 2 and 6 months post-hospitalization for Black and multiracial patients. PTSD symptoms were also found to improve faster among Latinx than White patients. Risk factors accounted for most racial/ethnic differences, although Latinx patients showed lower 6-month PTSD symptoms and Black patients lower acute and 2-month depression and anxiety symptoms after accounting for risk factors. Everyday discrimination, financial stress, past mental health problems, and social constraints were related to these differences. CONCLUSION: Racial/ethnic differences in risk factors explained most differences in acute and longer-term PTSD, depression, and anxiety symptoms. Understanding how these risk factors relate to posttraumatic symptoms could help reduce disparities by facilitating early identification of patients at risk for mental health problems.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Adulto , Humanos , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Grupos Raciais , Fatores de Risco , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Depressão/diagnóstico , Depressão/epidemiologia , Hospitalização
7.
R Soc Open Sci ; 8(9): 202255, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34527265

RESUMO

Decision makers with the responsibility of managing policy for the COVID-19 epidemic have faced difficult choices in balancing the competing claims of saving lives and the high economic cost of shutdowns. In this paper, we formulate a model with both epidemiological and economic content to assist this decision-making process. We consider two ways to handle the balance between economic costs and deaths. First, we use the statistical value of life, which in Canada is about C$7 million, to optimize over a single variable, which is the sum of the economic cost and the value of lives lost. Our second method is to calculate the Pareto optimal front when we look at the two variables-deaths and economic costs. In both cases we find that, for most parameter values, the optimal policy is to adopt an initial shutdown level which reduces the reproduction number of the epidemic to close to 1. This level is then reduced once a vaccination programme is underway. Our model also indicates that an oscillating policy of strict and mild shutdowns is less effective than a policy which maintains a moderate shutdown level.

8.
Mhealth ; 7: 30, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33898599

RESUMO

BACKGROUND: Smoking cessation Internet interventions have been shown to be comparable in effectiveness to the nicotine patch. The aim of this study was to develop a Spanish/English smoking cessation web app using input from low-income smokers, and to evaluate modifications to the online intervention in terms of its ability to engage smokers. METHODS: Three versions of a smoking cessation web app were developed and tested. Measures of engagement, such as completion of study registration, utilization of cigarette, mood, and craving trackers, and completion of follow-up assessments, were collected to determine whether changes in the website resulted in increased engagement. RESULTS: The third version of the website, which featured improved look-and-feel and fewer barriers to engagement, markedly increased tracker engagement from the first two versions. However, follow-up rates remained low across all three versions. CONCLUSIONS: The increase in engagement was attributed to the following modifications: A more inviting landing page with key intervention elements available immediately; an easily accessible dashboard with users' data; and tracking tools that were more user friendly. We conclude that in addition to adequate and functional elements, design principles are key factors in increasing engagement in online interventions.

9.
J R Army Med Corps ; 163(6): 371-375, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28982709

RESUMO

INTRODUCTION: High-altitude environments lead to a significant physiological challenge and disease processes which can be life threatening; operational effectiveness at high altitude can be severely compromised. The UK military research is investigating ways of mitigating the physiological effects of high altitude. METHODS: The British Service Dhaulagiri Research Expedition took place from March to May 2016, and the military personnel were invited to consent to a variety of study protocols investigating adaptation to high altitudes and diagnosis of high-altitude illness. The studies took place in remote and austere environments at altitudes of up to 7500 m. RESULTS: This paper gives an overview of the individual research protocols investigated, the execution of the expedition and the challenges involved. 129 servicemen and women were involved at altitudes of up to 7500 m; 8 research protocols were investigated. CONCLUSIONS: The outputs from these studies will help to individualise the acclimatisation process and inform strategies for pre-acclimatisation should troops ever need to deploy at high altitude at short notice.


Assuntos
Aclimatação , Doença da Altitude/prevenção & controle , Altitude , Pesquisa Biomédica , Medicina Militar , Comportamento Cooperativo , Feminino , Humanos , Masculino , Reino Unido
10.
J Hum Hypertens ; 31(11): 715-719, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28540933

RESUMO

Central arterial systolic blood pressure (SBP) and arterial stiffness are known to be better predictors of adverse cardiovascular outcomes than brachial SBP. The effect of progressive high altitude (HA) on these parameters has not been examined. Ninety healthy adults were included. Central BP and the augmentation index (AI) were measured at the level of the brachial artery (Uscom BP+ device) at <200 m and at 3619, 4600 and 5140 m. The average age of the subjects (70% men) were 32.2±8.7 years. Compared with central arterial pressures, brachial SBP (+8.1±6.4 mm Hg; P<0.0001) and pulse pressure (+10.9±6.6 mm Hg; P<0.0001) were significantly higher and brachial diastolic BP was lower (-2.8±1.6 mm Hg; P<0.0001). Compared with <200 m, HA led to a significant increase in brachial and central SBP. Central SBP correlated with AI (r=0.50; 95% confidence interval (CI): 0.41-0.58; P<0.0001) and age (r=0.32; 95% CI: 21-0.41; P<0.001). AI positively correlated with age (r=0.39; P<0.001) and inversely with subject height (r=-0.22; P<0.0001), weight (r=-0.19; P=0.006) and heart rate (r=-0.49; P<0.0001). There was no relationship between acute mountain sickness scores (Lake Louis Scoring System (LLS)) and AI or central BP. The independent predictors of central SBP were male sex (coefficient, t=4.7; P<0.0001), age (t=3.6; P=0.004) and AI (t=7.5; P<0.0001; overall r2=0.40; P<0.0001). Subject height (t=2.4; P=0.02), age (7.4; P<0.0001) and heart rate (t=11.4; P<0.0001) were the only independent predictors of AI (overall r2=0.43; P<0.0001). Central BP and AI significantly increase at HA. This rise was influenced by subject-related factors and heart rate but not independently by altitude, LLS or SpO2.


Assuntos
Doença da Altitude/fisiopatologia , Altitude , Pressão Arterial , Artéria Braquial/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Hipóxia/fisiopatologia , Rigidez Vascular , Aclimatação , Adulto , Doença da Altitude/diagnóstico , Doença da Altitude/etiologia , Estatura , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Feminino , Frequência Cardíaca , Humanos , Hipóxia/diagnóstico , Hipóxia/etiologia , Masculino , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
11.
Child Abuse Negl ; 65: 37-47, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28110110

RESUMO

Experiencing traumatic events and abuse is unfortunately common in general, non-clinical samples. Recent research indicates that the ways in which individuals interpret traumatic experiences, as well as the ways that they manage challenging emotions in general, may statistically predict post-traumatic stress disorder (PTSD) symptoms to a greater extent than does trauma itself. Negative trauma appraisals, generalized emotion regulation (ER) difficulties, and low levels of self-compassion have each been shown to influence the connection between trauma exposure and subsequent PTSD symptoms. However, little is known regarding how these processes interact, or their relative contributions to mental health after trauma. The current study analyzed data from 466 university students who completed self-report measures of childhood abuse, PTSD symptoms, trauma appraisals, ER difficulties, and self-compassion. Childhood abuse exposure and PTSD symptoms were positively associated with negative trauma appraisals and ER difficulties, and negatively associated with self-compassion. Self-compassion was inversely associated with negative trauma appraisals and ER difficulties. Multiple mediation analyses demonstrated that negative trauma appraisals, ER difficulties, and levels of self-compassion fully explained the link between abuse exposure and PTSD symptoms via several specific pathways. These findings suggest that researchers, clinicians, and abuse survivors can benefit from addressing these interconnected domains during treatment and recovery processes.


Assuntos
Maus-Tratos Infantis/psicologia , Emoções , Transtornos de Estresse Pós-Traumáticos/psicologia , Adolescente , Adulto , Criança , Empatia , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Autorrelato , Estados Unidos , Adulto Jovem
12.
Astrophys J ; 842(2)2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32601504

RESUMO

Infrared observations of the dusty, massive Homunculus Nebula around the luminous blue variable η Carinae are crucial to characterize the mass-loss history and help constrain the mechanisms leading to the Great Eruption. We present the 2.4 - 670 µm spectral energy distribution, constructed from legacy ISO observations and new spectroscopy obtained with the Herschel Space Observatory. Using radiative transfer modeling, we find that the two best-fit dust models yield compositions which are consistent with CNO-processed material, with iron, pyroxene and other metal-rich silicates, corundum, and magnesium-iron sulfide in common. Spherical corundum grains are supported by the good match to a narrow 20.2 µm feature. Our preferred model contains nitrides AlN and Si3N4 in low abundances. Dust masses range from 0.25 to 0.44 M ʘ but M tot ≥ 45 M ʘ in both cases due to an expected high Fe gas-to-dust ratio. The bulk of dust is within a 5″ × 7″ central region. An additional compact feature is detected at 390 µm. We obtain L IR = 2.96 × 106 L ʘ, a 25% decline from an average of mid-IR photometric levels observed in 1971-1977. This indicates a reduction in circumstellar extinction in conjunction with an increase in visual brightness, allowing 25-40% of optical and UV radiation to escape from the central source. We also present an analysis of 12CO and 13CO J = 5 - 4 through 9 - 8 lines, showing that the abundances are consistent with expectations for CNO-processed material. The [12C II] line is detected in absorption, which we suspect originates in foreground material at very low excitation temperatures.

13.
Int J Sports Med ; 37(10): 825-30, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27337430

RESUMO

The purpose of this study was to assess the reliability of a pre-loaded 1 500-m treadmill time trial, conducted in moderate normobaric hypoxia. 8 trained runners/triathletes (24±3 years, 73.2±8.1 kg, 182.5±6.5 cm, altitude specific V˙O2max: 52.9±5.5 ml·kg(-1)·min(-1)) completed 3 trials (the first as a familiarisation), involving 2, 15-min running bouts at 45% and 65% V˙O2max, respectively, and a 1 500-m time trial in moderate normobaric hypoxia equivalent to a simulated altitude of 2 500 m (FiO2~15%). Heart rate, arterial oxygen saturation, skeletal muscle and cerebral tissue oxygenation (StO2), expired gas ( V˙O2 and V˙CO2), and ratings of perceived exertion were monitored. Running performance (Trial 1: 352.7±40; Trial 2: 353.9±38.2 s) demonstrated a low CV (0.9%) and high ICC (1). All physiological variables demonstrated a global CV≤4.2%, and ICC≥0.87, with the exception of muscle (CV 10.4%; ICC 0.70) and cerebral (CV 4.1%; ICC 0.82) StO2. These data demonstrate good reliability of the majority of physiological variables and indicate that a pre-loaded 1 500-m time trial conducted in moderate normobaric hypoxia is a highly reliable test of performance.


Assuntos
Frequência Cardíaca/fisiologia , Hipóxia/metabolismo , Músculo Esquelético/fisiologia , Corrida/fisiologia , Adulto , Teste de Esforço , Humanos , Masculino , Oxigênio/sangue , Troca Gasosa Pulmonar , Reprodutibilidade dos Testes , Adulto Jovem
14.
Bone Joint J ; 98-B(1 Suppl A): 54-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26733642

RESUMO

We describe our technique and rationale using hybrid fixation for primary total hip arthroplasty (THA) at the Hospital for Special Surgery. Modern uncemented acetabular components have few screw holes, or no holes, polished inner surfaces, improved locking mechanisms, and maximised thickness and shell-liner conformity. Uncemented sockets can be combined with highly cross-linked polyethylene liners, which have demonstrated very low wear and osteolysis rates after ten to 15 years of implantation. The results of cement fixation with a smooth or polished surface finished stem have been excellent, virtually eliminating complications seen with cementless fixation like peri-operative femoral fractures and thigh pain. Although mid-term results of modern cementless stems are encouraging, the long-term data do not show reduced revision rates for cementless stems compared with cemented smooth stems. In this paper we review the conduct of a hybrid THA, with emphasis on pre-operative planning, surgical technique, hypotensive epidural anaesthesia, and intra-operative physiology.


Assuntos
Artroplastia de Quadril/métodos , Prótese de Quadril , Osteoartrite do Quadril/cirurgia , Hospitais , Humanos , Cuidados Intraoperatórios , Cuidados Pré-Operatórios , Desenho de Prótese , Ajuste de Prótese
15.
Artigo em Inglês | MEDLINE | ID: mdl-24396569

RESUMO

BACKGROUND: Some people with dissociative identity disorder (DID) have very little communication or awareness among the parts of their identity, while others experience a great deal of cooperation among alternate identities. Previous research on this topic has been sparse. Currently, there is no empirical measure of integration versus fragmentation in a person with DID. In this study, we report the development of such a measure. OBJECTIVE: The goal of this study was to pilot the integration measure (IM) and to address its psychometric properties and relationships to other measures. The IM is the first standardized measure of integration in DID. METHOD: Eleven women with DID participated in an experiment that included a variety of tasks. They filled out questionnaires about trauma and dissociation as well as the IM. They also provided verbal results about switching among alternate identities during the study sessions. RESULTS: Participants switched among identities an average of 5.8 times during the first session, and switching was highly correlated with trauma. Integration was related to switching, though this relationship may be non-linear. Integration was not related to time in psychotherapy. CONCLUSIONS: The IM provides a useful beginning to quantify and study integration and fragmentation in DID. Directions for future research are also discussed, including expanding the IM from this pilot. The IM may be useful in treatment settings to assess progress or change over time.

16.
Astrophys J Lett ; 796(1)2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26722620

RESUMO

We report on the discovery of strong intensity variations in the high rotational lines of abundant molecular species towards the archetypical circumstellar envelope of IRC+10216. The observations have been carried out with the HIFI instrument on board Herschel and with the IRAM 30-m telescope. They cover several observing periods spreading over 3 years. The line intensity variations for molecules produced in the external layers of the envelope most probably result from time variations in the infrared pumping rates. We analyze the main implications this discovery has on the interpretation of molecular line emission in the envelopes of Mira-type stars. Radiative transfer calculations have to take into account both the time variability of infrared pumping and the possible variation of the dust and gas temperatures with stellar phase in order to reproduce the observation of molecular lines at different epochs. The effect of gas temperature variations with stellar phase could be particularly important for lines produced in the innermost regions of the envelope. Each layer of the circumstellar envelope sees the stellar light radiation with a different lag time (phase). Our results show that this effect must be included in the models. The sub-mm and FIR lines of AGB stars cannot anymore be considered as safe intensity calibrators.

17.
Science ; 342(6164): 1343-5, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24337290

RESUMO

Noble gas molecules have not hitherto been detected in space. From spectra obtained with the Herschel Space Observatory, we report the detection of emission in the 617.5- and 1234.6-gigahertz J = 1-0 and 2-1 rotational lines of (36)ArH(+) at several positions in the Crab Nebula, a supernova remnant known to contain both molecular hydrogen and regions of enhanced ionized argon emission. Argon-36 is believed to have originated from explosive nucleosynthesis in massive stars during core-collapse supernova events. Its detection in the Crab Nebula, the product of such a supernova event, confirms this expectation. The likely excitation mechanism for the observed (36)ArH(+) emission lines is electron collisions in partially ionized regions with electron densities of a few hundred per centimeter cubed.

18.
J Trauma Stress ; 26(3): 376-84, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23737296

RESUMO

Emotion regulation difficulties following trauma exposure have received increasing attention among researchers and clinicians. Previous work highlights the role of emotion regulation difficulties in multiple forms of psychological distress and identifies emotion regulation capacities as especially compromised among survivors of betrayal trauma: physical, sexual, or emotional maltreatment perpetrated by someone to whom the victim is close, such as a parent or partner. It is unknown, however, whether links between emotion regulation difficulties and psychological symptoms differ following exposure to betrayal trauma as compared with other trauma types. In the present study, 593 male and female university undergraduates completed the Difficulties with Emotion Regulation Scale (Gratz & Roemer, 2004), the Brief Betrayal Trauma Scale (Goldberg & Freyd, 2006), the Impact of Event Scale (Horowitz, Wilner, & Alvarez, 1979), and the Trauma Symptom Checklist (Elliott & Briere, 1992). A path analytic model demonstrated that betrayal trauma indirectly impacted symptoms of intrusion (ß = .11), avoidance (ß = .13), depression (ß = .17), and anxiety (ß = .14) via emotion regulation difficulties, an effect consistent with mediation. Emotion regulation difficulties did not mediate the relationship between other trauma exposure and psychological symptoms. Results may inform treatment-matching efforts, and suggest that emotion regulation difficulties may constitute a key therapeutic target following betrayal trauma.


Assuntos
Sintomas Afetivos/psicologia , Relações Interpessoais , Violência/psicologia , Adolescente , Adulto , Sintomas Afetivos/epidemiologia , Fatores Etários , Ansiedade/epidemiologia , Ansiedade/psicologia , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Fatores Sexuais , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto Jovem
19.
Nature ; 490(7418): 74-6, 2012 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-23038467

RESUMO

Some planetary systems harbour debris disks containing planetesimals such as asteroids and comets. Collisions between such bodies produce small dust particles, the spectral features of which reveal their composition and, hence, that of their parent bodies. A measurement of the composition of olivine crystals (Mg(2-2x)Fe(2x)SiO(4)) has been done for the protoplanetary disk HD 100546 (refs 3, 4) and for olivine crystals in the warm inner parts of planetary systems. The latter compares well with the iron-rich olivine in asteroids (x ≈ 0.29). In the cold outskirts of the ß Pictoris system, an analogue to the young Solar System, olivine crystals were detected but their composition remained undetermined, leaving unknown how the composition of the bulk of Solar System cometary olivine grains compares with that of extrasolar comets. Here we report the detection of the 69-micrometre-wavelength band of olivine crystals in the spectrum of ß Pictoris. Because the disk is optically thin, we can associate the crystals with an extrasolar proto-Kuiper belt a distance of 15-45 astronomical units from the star (one astronomical unit is the Sun-Earth distance), determine their magnesium-rich composition (x = 0.01 ± 0.001) and show that they make up 3.6 ± 1.0 per cent of the total dust mass. These values are strikingly similar to those for the dust emitted by the most primitive comets in the Solar System, even though ß Pictoris is more massive and more luminous and has a different planetary system architecture.

20.
Science ; 333(6047): 1258-61, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21737700

RESUMO

We report far-infrared and submillimeter observations of supernova 1987A, the star whose explosion was observed on 23 February 1987 in the Large Magellanic Cloud, a galaxy located 160,000 light years away. The observations reveal the presence of a population of cold dust grains radiating with a temperature of about 17 to 23 kelvin at a rate of about 220 times the luminosity of the Sun. The intensity and spectral energy distribution of the emission suggest a dust mass of about 0.4 to 0.7 times the mass of the Sun. The radiation must originate from the supernova ejecta and requires the efficient precipitation of all refractory material into dust. Our observations imply that supernovae can produce the large dust masses detected in young galaxies at very high redshifts.

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