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1.
medRxiv ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38883764

RESUMO

Background: Past studies associating personality with psychosis have been limited by small nonclinical samples and a focus on general symptom burden. This study uses a large clinical sample to examine personality's relationship with psychosis-specific features and compare personality dimensions across clinically and neurobiologically defined categories of psychoses. Methods: A total of 1352 participants with schizophrenia, schizoaffective disorder, and bipolar with psychosis, as well as 623 healthy controls (HC), drawn from the Bipolar-Schizophrenia Network for Intermediate Phenotypes (BSNIP-2) study, were included. Three biomarker-derived biotypes were used to separately categorize the probands. Mean personality factors (openness, conscientiousness, extraversion, agreeableness, and neuroticism) were compared between HC and proband subgroups using independent sample t-tests. A robust linear regression was utilized to determine personality differences across biotypes and diagnostic subgroups. Associations between personality factors and cognition were determined through Pearson's correlation. A canonical correlation was run between the personality factors and general functioning, positive symptoms, and negative symptoms to delineate the relationship between personality and clinical outcomes of psychosis. Results: There were significant personality differences between the proband and HC groups across all five personality factors. Overall, the probands had higher neuroticism and lower extraversion, agreeableness, conscientiousness, and openness. Openness showed the greatest difference across the diagnostic subgroups and biotypes, and greatest correlation with cognition. Openness, agreeableness, and extraversion had the strongest associations with symptom severity. Conclusions: Individuals with psychosis have different personality profiles compared to HC. In particular, openness may be relevant in distinguishing psychosis-specific phenotypes and experiences, and associated with biological underpinnings of psychosis, including cognition. Further studies should identify potential causal factors and mediators of this relationship.

2.
Phys Rev Lett ; 120(6): 061802, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481237

RESUMO

We report the result of a blinded search for weakly interacting massive particles (WIMPs) using the majority of the SuperCDMS Soudan data set. With an exposure of 1690 kg d, a single candidate event is observed, consistent with expected backgrounds. This analysis (combined with previous Ge results) sets an upper limit on the spin-independent WIMP-nucleon cross section of 1.4×10^{-44} (1.0×10^{-44}) cm^{2} at 46 GeV/c^{2}. These results set the strongest limits for WIMP-germanium-nucleus interactions for masses >12 GeV/c^{2}.

3.
Phys Rev Lett ; 116(16): 161101, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27152783

RESUMO

We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in the γ-ray spectrum of NGC 1275, the central galaxy of the Perseus cluster. Using 6 years of Fermi Large Area Telescope data, we find no evidence for ALPs and exclude couplings above 5×10^{-12} GeV^{-1} for ALP masses 0.5≲m_{a}≲5 neV at 95% confidence. The limits are competitive with the sensitivity of planned laboratory experiments, and, together with other bounds, strongly constrain the possibility that ALPs can reduce the γ-ray opacity of the Universe.

4.
Phys Rev Lett ; 116(7): 071301, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943526

RESUMO

The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in the search for weakly interacting massive particles (WIMPs). Results are presented from the second CDMSlite run with an exposure of 70 kg day, which reached an energy threshold for electron recoils as low as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space for the WIMP-nucleon spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5 GeV/c^{2}.

5.
Phys Rev D ; 93(8): 082001, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32743154

RESUMO

We have measured the gamma-ray emission spectrum of the Moon using the data collected by the Large Area Telescope onboard the Fermi satellite during its first seven years of operation, in the energy range from 30 MeV up to a few GeV. We have also studied the time evolution of the flux, finding a correlation with the solar activity. We have developed a full Monte Carlo simulation describing the interactions of cosmic rays with the lunar surface. The results of the present analysis can be explained in the framework of this model, where the production of gamma rays is due to the interactions of cosmic-ray proton and helium nuclei with the surface of the Moon. Finally, we have used our simulation to derive the cosmic-ray proton and helium spectra near Earth from the Moon gamma-ray data.

6.
Phys Rev Lett ; 114(11): 111302, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25839256

RESUMO

While the standard model of particle physics does not include free particles with fractional charge, experimental searches have not ruled out their existence. We report results from the Cryogenic Dark Matter Search (CDMS II) experiment that give the first direct-detection limits for cosmogenically produced relativistic particles with electric charge lower than e/6. A search for tracks in the six stacked detectors of each of two of the CDMS II towers finds no candidates, thereby excluding new parameter space for particles with electric charges between e/6 and e/200.

7.
Phys Rev Lett ; 112(24): 241302, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24996080

RESUMO

We report a first search for weakly interacting massive particles (WIMPs) using the background rejection capabilities of SuperCDMS. An exposure of 577 kg days was analyzed for WIMPs with mass <30 GeV/c(2), with the signal region blinded. Eleven events were observed after unblinding. We set an upper limit on the spin-independent WIMP-nucleon cross section of 1.2×10(-42) cm(2) at 8 GeV/c(2). This result is in tension with WIMP interpretations of recent experiments and probes new parameter space for WIMP-nucleon scattering for WIMP masses <6 GeV/c(2).

9.
Anaesthesia ; 69(4): 306-13, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24641636

RESUMO

Current guidelines for intra-operative fluid management recommend the use of increments in stroke volume following intravenous fluid bolus administration as a guide to subsequent fluid therapy. To study the physiological premise of this paradigm, we tested the hypothesis that healthy, non-starved volunteers would develop an increment in their stroke volume following a passive leg raise manoeuvre. Subjects were positioned supine and stroke volume was measured by transthoracic echocardiography at baseline, 30 s, 1 min, 3 min and 5 min after passive leg raise manoeuvre to 45°. Stroke volume was measured at end-expiration during quiet breathing, as the mean of three sequential measurements. Seventeen healthy volunteers were recruited; one volunteer in whom it was not possible to obtain Doppler measurements and a further five for reasons of poor Doppler image quality were not included in the study. Mean (SD) percentage difference from baseline to the largest change in stroke volume was 5.7 (9.6)% (p = 0.16). Of the 11 volunteers evaluated, five (45%) had stroke volume increases of greater than 10%. Mean (SD) maximum percentage change in cardiac index was 14.8 (9.7)% (p = 0.004). A wide variation in baseline stroke volume and response to the passive leg raise manoeuvre was seen, suggesting greater heterogeneity in the normal population than current clinical guidelines recognise.


Assuntos
Ecocardiografia/métodos , Perna (Membro)/fisiologia , Volume Sistólico/fisiologia , Adolescente , Adulto , Pressão Sanguínea/fisiologia , Débito Cardíaco , Feminino , Hidratação , Frequência Cardíaca/fisiologia , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Estudos Prospectivos , Fluxo Sanguíneo Regional , Decúbito Dorsal/fisiologia , Adulto Jovem
10.
Phys Rev Lett ; 112(4): 041302, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24580434

RESUMO

SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of 170 eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

11.
Astrophys J ; 784(2)2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34646038

RESUMO

Observations of occultations of bright γ-ray sources by the Sun may reveal predicted pair halos around blazars and/or new physics, such as, e.g., hypothetical light dark matter particles-axions. We use Fermi Gamma-Ray Space Telescope (Fermi) data to analyze four occultations of blazar 3C 279 by the Sun on October 8 each year from 2008 to 2011. A combined analysis of the observations of these occultations allows a point-like source at the position of 3C 279 to be detected with significance of ≈3σ, but does not reveal any significant excess over the flux expected from the quiescent Sun. The likelihood ratio test rules out complete transparency of the Sun to the blazar γ-ray emission at a 3σ confidence level.

12.
Curr Opin Crit Care ; 19(6): 624-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24240829

RESUMO

PURPOSE OF REVIEW: Decisions to limit life-sustaining therapy (DLLST) in the ICU are used to uphold patients' autonomy, protect them from non-beneficial treatment and fairly distribute resources. The institution of these decisions is complex, with a variety of qualitative and quantitative data published. This review aims to summarize the main issues and review the contemporary research findings on this subject. RECENT FINDINGS: DLLST are used in a variety of clinical and non-clinical situations, before and after ICU admission, and are not always part of end-of-life management. There are many dilemmas and barriers that beset their institution. Many ICU physicians feel inadequately trained to carry them out and they are frequently a source of conflict. A variety of strategies have been examined to improve their institution, including advanced directives, intensive communication strategies and family information leaflets, many of which have improved patient and family-centred outcomes. SUMMARY: There are a number of uncertainties that beset the institution of DLLST in the ICU; however, a variety of research has improved our ability to understand and implement them. This review frames some of the dilemmas and discusses some of the procedural strategies that have been used to improve outcomes.


Assuntos
Unidades de Terapia Intensiva , Cuidados para Prolongar a Vida , Assistência Terminal , Suspensão de Tratamento , Comunicação , Tomada de Decisões , Eutanásia Passiva/ética , Eutanásia Passiva/tendências , Família/psicologia , Feminino , Humanos , Cuidados para Prolongar a Vida/ética , Cuidados para Prolongar a Vida/psicologia , Masculino , Autonomia Pessoal , Relações Profissional-Família , Assistência Terminal/ética , Assistência Terminal/psicologia
13.
Phys Rev Lett ; 111(25): 251301, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24483735

RESUMO

We report results of a search for weakly interacting massive particles (WIMPS) with the silicon detectors of the CDMS II experiment. This blind analysis of 140.2 kg day of data taken between July 2007 and September 2008 revealed three WIMP-candidate events with a surface-event background estimate of 0.41(-0.08)(+0.20)(stat)(-0.24)(+0.28)(syst). Other known backgrounds from neutrons and 206Pb are limited to <0.13 and <0.08 events at the 90% confidence level, respectively. The exposure of this analysis is equivalent to 23.4 kg day for a recoil energy range of 7-100 keV for a WIMP of mass 10 GeV/c2. The probability that the known backgrounds would produce three or more events in the signal region is 5.4%. A profile likelihood ratio test of the three events that includes the measured recoil energies gives a 0.19% probability for the known-background-only hypothesis when tested against the alternative WIMP+background hypothesis. The highest likelihood occurs for a WIMP mass of 8.6 GeV/c2 and WIMP-nucleon cross section of 1.9×10(-41) cm2.

14.
Science ; 334(6059): 1103-7, 2011 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-22116880

RESUMO

The origin of Galactic cosmic rays is a century-long puzzle. Indirect evidence points to their acceleration by supernova shockwaves, but we know little of their escape from the shock and their evolution through the turbulent medium surrounding massive stars. Gamma rays can probe their spreading through the ambient gas and radiation fields. The Fermi Large Area Telescope (LAT) has observed the star-forming region of Cygnus X. The 1- to 100-gigaelectronvolt images reveal a 50-parsec-wide cocoon of freshly accelerated cosmic rays that flood the cavities carved by the stellar winds and ionization fronts from young stellar clusters. It provides an example to study the youth of cosmic rays in a superbubble environment before they merge into the older Galactic population.

15.
Am J Obstet Gynecol ; 189(5): 1398-400, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14634576

RESUMO

OBJECTIVE: The purpose of this study was to assess the association of presumptive Trichomonas vaginalis treatment during pregnancy and birth outcomes. STUDY DESIGN: A community-randomized trial of presumptive sexually transmitted disease treatment during pregnancy was conducted between 1994 and 1999 in Rakai district, Uganda. A subanalysis of a trial of presumptive therapy with azithromycin, cefixime, and metronidazole assessed Trichomonas vaginalis treatment in pregnant women. RESULTS: Children of 94 women with Trichomonas who were treated had increased low birth weight (relative risk, 2.49; 95% CI, 1.12-5.50), preterm birth rate (relative risk, 1.28; 95% CI, 0.81-2.02), and 2-year mortality rate (relative risk, 1.58; 95% CI, 0.99-2.52), compared with children of 112 women with Trichomonas who were not treated. CONCLUSION: Treatment of Trichomonas vaginalis during pregnancy may be deleterious, and we infer that this may be due to metronidazole. This is consistent with a National Institute for Child Health and Human Development trial that found an excess of preterm births in children of women with Trichomonas vaginalis infection who were treated with metronidazole.


Assuntos
Antitricômonas/efeitos adversos , Metronidazol/efeitos adversos , Complicações Infecciosas na Gravidez/tratamento farmacológico , Vaginite por Trichomonas/tratamento farmacológico , Trichomonas vaginalis , Animais , Coeficiente de Natalidade , Quimioterapia Combinada , Feminino , Humanos , Mortalidade Infantil , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Trabalho de Parto Prematuro/induzido quimicamente , Gravidez , Resultado da Gravidez , Risco , Uganda
16.
J Emerg Med ; 16(1): 5-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9472752

RESUMO

We investigated the diagnostic utility of transthoracic echocardiogram (2-D ECHO) in identifying acute right heart strain in patients with suspected pulmonary embolus (PE) undergoing a pulmonary angiogram during their hospitalization. A retrospective case control study was conducted over a 3-year period at a tertiary, community teaching hospital. Patients were eligible if they had a pulmonary angiogram and a transthoracic echocardiogram. Cases were defined as an angiogram positive for PE and controls were defined as an angiogram negative for PE. We excluded cases in which the time interval between 2-D ECHO and angiogram was greater than 2 days. The 2-D ECHO was considered positive for right heart strain if two of the following were present: enlarged right ventricle, moderate or severe tricuspid regurgitation, increased right ventricular pressures, or paradoxical septal wall motion. We were able to identify 71 patients, of whom 24 met our criteria for PE. Of these, 13 had an echocardiogram consistent with our definition of acute right heart strain, for a sensitivity of 0.54. Forty-six of the 47 patients without PE did not have findings of acute right heart strain. The echocardiogram was positive in 14 patients, for a positive predictive value of 0.93. In seven patients with systolic blood pressures of less than 100 mmHg, five had a PE, all of whom met our criteria for acute right heart strain. We conclude that 2-D ECHOs show promise in identifying PE and hemodynamic compromise as a result of PE, and that further studies are warranted.


Assuntos
Angiografia/métodos , Ecocardiografia/métodos , Embolia Pulmonar/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
17.
Vox Sang ; 72(2): 79-84, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9088074

RESUMO

BACKGROUND AND OBJECTIVES: To determine whether antibody to hepatitis B core (anti-HBc) reactivity, as a marker of hepatitis B virus infection, reflects a 'lifestyle' risk in donors in North London, we have obtained detailed histories from donors with various manifestations of HBV infection. MATERIALS AND METHODS: Interviews based on a standardised questionnaire were conducted with 70 donors confirmed to be anti-HBc reactive. RESULTS: Comparison with controls (known to be anti-HBc-negative) and donors reactive for anti-hepatitis-C virus showed that current donor strategies are effective; in our area, reactivity for anti-HBc is not associated with a lifestyle risk for those donors who are unreactive in current mandatory screening tests. CONCLUSIONS: Blood from donors positive for both anti-HBc and anti-HBs should be considered suitable for transfusion purposes. This is consistent with the practice of accepting blood from naturally immune donors for preparation of hepatitis B immunoglobulin.


Assuntos
Anticorpos Antivirais/imunologia , Doadores de Sangue , Vírus da Hepatite B/imunologia , Hepatite B/transmissão , Reação Transfusional , Proteínas do Core Viral/imunologia , Anticorpos Antivirais/sangue , Hepatite B/virologia , Vírus da Hepatite B/isolamento & purificação , Humanos , Londres , Fatores de Risco
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