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1.
Phys Rev Lett ; 127(16): 162501, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34723594

RESUMO

We report an improved measurement of the free neutron lifetime τ_{n} using the UCNτ apparatus at the Los Alamos Neutron Science Center. We count a total of approximately 38×10^{6} surviving ultracold neutrons (UCNs) after storing in UCNτ's magnetogravitational trap over two data acquisition campaigns in 2017 and 2018. We extract τ_{n} from three blinded, independent analyses by both pairing long and short storage time runs to find a set of replicate τ_{n} measurements and by performing a global likelihood fit to all data while self-consistently incorporating the ß-decay lifetime. Both techniques achieve consistent results and find a value τ_{n}=877.75±0.28_{stat}+0.22/-0.16_{syst} s. With this sensitivity, neutron lifetime experiments now directly address the impact of recent refinements in our understanding of the standard model for neutron decay.

2.
Fam Community Health ; 44(1): 21-31, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33055574

RESUMO

This study uses primary data from a community-based random sample of adults in historically lower-income African American (or Black) neighborhoods in Atlanta, Georgia (N = 352). The aim was to investigate whether there are race differences in perceived neighborhood conditions/amenities, and the potential conditional effect of race on the relationship between the perceived built environment and physical limitations. Findings indicate significant race differences in the perceived built environment and that the relationship between the perceived built environment and physical limitations is conditioned by race, whereby Whites experience greater physical health benefits from more neighborhood conditions/amenities than African Americans.


Assuntos
Ambiente Construído , Exercício Físico , Características de Residência , Adulto , Negro ou Afro-Americano , Georgia , Humanos , Percepção , Pobreza
3.
Intern Med J ; 45(5): 537-45, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25583161

RESUMO

BACKGROUND: High on-treatment platelet reactivity has been associated with poor outcomes following acute coronary syndromes (ACS). Both the loss of function CYP2C19*2 allele and the gain of function CYP2C19*17 allele along with a range of clinical characteristics have been associated with variation in the response to clopidogrel. AIM: The study aims to examine the frequency of CYP2C19 variants and understand the factors associated with on-treatment platelet reactivity in a New Zealand ACS population. METHODS: We prospectively enrolled 312 ACS patients. We collected clinical characteristics and measured on-treatment platelet reactivity using two validated point-of-care assays, VerifyNow and Multiplate. DNA was extracted and CYP2C19*2 and *17 alleles were identified using real-time polymerase chain reaction. RESULTS: CYP2C19*2 or CYP2C19*17 alleles were observed in 101 (32%) and 106 (34%) of patients, respectively, with significant differences in distribution by ethnicity. In Maori and Pacific Island patients, 47% (confidence interval (CI) 31-63%) had CYP2C19*2 and 11% (CI 4-19%) CYP2C19*17 compared with 26% (CI 19-32%) and 41% (CI 32-49%) in white people. Carriage of CYP2C19*2 alleles was associated with higher levels of platelet reactivity measured by either assay, but we observed no relationship between platelet reactivity and CYP2C19*17. In multivariate analysis diabetes, clopidogrel dose and CYP2C19*2 status were all significant independent predictors of platelet reactivity. CONCLUSIONS: Both CYP2C19*2 and *17 were common in a New Zealand ACS population, with CYP2C19*2 observed in almost half the Maori and Pacific Island patients. CYP2C19*2, diabetes and clopidogrel dose were independent contributors to on-treatment platelet reactivity.


Assuntos
Síndrome Coronariana Aguda/genética , Plaquetas/patologia , Citocromo P-450 CYP2C19/genética , Inibidores da Agregação Plaquetária/uso terapêutico , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/epidemiologia , Alelos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Testes de Função Plaquetária , Prevalência , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Índice de Gravidade de Doença
4.
J Health Commun ; 20(4): 377-86, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25529115

RESUMO

This article contributes to the burgeoning literature on the social determinants of health disparities. The authors investigate how communication resources and collective efficacy, independently and in combination, shape residents' access to health enhancing resources (including healthcare services, sources of healthier food options, and public recreation spaces) in their communities. Using random digit dial telephone survey data from 833 residents of South Los Angeles communities the authors show that communicative social capital-that is, an information and problem-solving resource that accrues to residents as they become more integrated into their local communication network of neighbors, community organizations, and local media-plays a significant role in access to health resources. This relationship is complicated by individuals' health insurance and health status, as communicative social capital magnifies the sense of absence of resources for those who are in worse health and lack insurance. Communicative social capital builds collective efficacy, which is positively related to access to health-enhancing resources, but it also mediates the negative relationship between communicative social capital and access to health resources. Residents with richer stores of communicative social capital and collective efficacy report better access to health resources. The authors conclude with a discussion of implications of these findings and suggestions for future research.


Assuntos
Comunicação , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Capital Social , Determinantes Sociais da Saúde , Adulto , Feminino , Disparidades nos Níveis de Saúde , Humanos , Seguro Saúde/estatística & dados numéricos , Los Angeles , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos
5.
J Health Commun ; 20(6): 710-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25928242

RESUMO

African Americans and Latinos are at disproportionately high risk for obesity and for the chronic conditions and diseases associated with it. This study uses communication infrastructure theory to explore how connections to neighborhood communication resources and communication with family members can affect residents' regular exercise and healthy eating behaviors-two of the most direct strategies for achieving or maintaining a healthy weight. Regression analyses revealed that connections to the neighborhood storytelling network and family interaction predicted residents' regular exercise and that family interaction had the strongest effect on the likelihood of exercising regularly. Family interaction was the only independent variable that predicted residents' daily intake of fruits and vegetables. Implications of these findings for community health programs and theory development are discussed.


Assuntos
Negro ou Afro-Americano/psicologia , Comunicação , Hispânico ou Latino/psicologia , Obesidade/etnologia , Obesidade/prevenção & controle , Apoio Social , População Urbana , Adolescente , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Exercício Físico/psicologia , Relações Familiares/etnologia , Comportamento Alimentar/etnologia , Feminino , Frutas , Comportamentos Relacionados com a Saúde/etnologia , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Teoria Psicológica , População Urbana/estatística & dados numéricos , Verduras , Adulto Jovem
6.
Int J Spine Surg ; 18(1): 69-72, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38228370

RESUMO

BACKGROUND: Postoperative spinal epidural hematomas (pSEHs) are a rare complication of microdiscectomy surgery. The hematoma may be unnoticed intraoperatively, but timely treatment may prevent permanent neurologic impairment. Airway management in patients with a full stomach is generally performed with rapid sequence intubation and general anesthesia. Awake spine surgery without intravenous analgesia or sedation may be beneficial in patients with a full stomach who are at higher risk for pulmonary aspiration with general anesthesia due to a loss of non-per-oral (NPO) status. The authors propose that it can also be performed in cases of urgent/emergent postsurgical epidural hematoma evacuation. METHODS: We present the airway management of a 41-year-old man who underwent a minimally invasive microdiscectomy with normal strength immediately after surgery but developed progressive weakness with right foot dorsiflexion, right extensor hallucis longus muscle weakness, and progressive right lower extremity ascending numbness over the course of the first 2 hours after surgery due to an epidural hematoma. RESULTS: The patient underwent urgent awake epidural hematoma evacuation with a spinal anesthetic. Afterward, the patient recovered neurological function and was discharged the following morning. CLINICAL RELEVANCE: pSEHs are a rare complication of microdiscectomy surgery. The purpose of this article is to describe the novel use of awake spine surgery in emergent epidural hematoma evacuation and demonstrate its feasibility. CONCLUSIONS: In emergencies, when a patient is not NPO, awake spine surgery can safely be performed with no sedation, ensuring the patient can protect their airway and avoid the risk of aspiration.

7.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38573050

RESUMO

A study of the dead layer thickness and quenching factor of a plastic scintillator for use in ultracold neutron (UCN) experiments is described. Alpha spectroscopy was used to determine the thickness of a thin surface dead layer to be 630 ± 110 nm. The relative light outputs from the decay of 241Am and Compton scattering of electrons were used to extract Birks' law coefficient, yielding a kB value of 0.087 ± 0.003 mm/MeV, consistent with some previous reports for other polystyrene-based scintillators. The results from these measurements are incorporated into the simulation to show that an energy threshold of (∼9 keV) can be achieved for the UCNProBe experiment. This low threshold enables high beta particle detection efficiency and the indirect measurement of UCN. The ability to make the scintillator deuterated, accompanied by its relatively thin dead layer, gives rise to unique applications in a wide range of UCN experiments, where it can be used to trap UCN and detect charged particles in situ.

8.
Health Commun ; 28(3): 275-85, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22716025

RESUMO

Studies have documented the frustrations patients experience during long wait times in emergency departments (EDs), but considerably less research has sought to understand ED staff responses to these frustrations. In-depth interviews were conducted with 18 ED social workers, patient navigators, and medical staff members at a large urban hospital regarding their experiences and interpersonal strategies for dealing with frustrated patients. Staff indicated that patients often attribute delays to neglect and do not understand why their health problem is not prioritized. They voiced several strategies for addressing wait time frustrations, including expressing empathy for patients, making patients feel occupied and wait times seem more productive, and educating patients about when health issues should be treated through primary care. All staff members recognized the need for engaging in empathic communication with frustrated patients, but social workers and patient navigators were able to dedicate more time to these types of interactions.


Assuntos
Serviço Hospitalar de Emergência , Listas de Espera , Comunicação , Empatia , Frustração , Humanos , Entrevistas como Assunto , Educação de Pacientes como Assunto , Relações Profissional-Paciente
9.
Health Educ Res ; 27(6): 1031-42, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22907536

RESUMO

Access to continuous care through a primary care provider is associated with improved health outcomes, but many communities rely on emergency departments (EDs) for both emergent and non-emergent health problems. This article describes one portion of a community-based participatory research project and investigates the type of education that might be needed as part of a larger intervention to encourage use of a local primary care clinic. In this article we examine how people who live in a low-income urban community and the healthcare workers who serve them conceptualize 'emergency medical condition'. We conducted forum and focus group discussions with 52 community members and individual interviews with 32 healthcare workers. Our findings indicate that while community members share a common general definition of what constitutes a medical emergency, they also desire better guidelines for how to assess health problems as requiring emergency versus primary care. Pain, uncertainty and anxiety tend to influence their choice to use EDs rather than availability of primary care. Implications for increasing primary care use are discussed.


Assuntos
Emergências/psicologia , Serviços Médicos de Emergência , Pessoal de Saúde/psicologia , Promoção da Saúde , Mau Uso de Serviços de Saúde/prevenção & controle , Atenção Primária à Saúde/estatística & dados numéricos , Adolescente , Adulto , Pesquisa Participativa Baseada na Comunidade , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adulto Jovem
10.
Intern Med J ; 41(3): 283-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21426466

RESUMO

We report the case of the case of a 56 year old female with sepsis on a background of rheumatoid arthritis and steroid use manifesting with overt clinical features of scurvy. Ascorbic acid assays were able to demonstrate severe deficiency and confirm a diagnosis of scurvy. Clinical resolution of signs and symptoms following commencement of vitamin C replacement was rapid. The intensivist and dietitian need to consider this diagnosis even in the first world setting, particularly in the presence of sepsis, inflammatory conditions, steroid use and importantly malnutrition.


Assuntos
Deficiência de Ácido Ascórbico/diagnóstico , Unidades de Terapia Intensiva , Escorbuto/diagnóstico , Ácido Ascórbico/uso terapêutico , Deficiência de Ácido Ascórbico/complicações , Deficiência de Ácido Ascórbico/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Militares , Peste , Escorbuto/complicações , Escorbuto/tratamento farmacológico , Sepse/complicações , Sepse/tratamento farmacológico
11.
Health Educ Res ; 26(2): 239-53, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21303816

RESUMO

Health issues disproportionately affect Latinos, but variations within this ethnic group may mean that some Latinos are harder to reach with health messages than others. This paper introduces a methodology grounded in communication infrastructure theory to better target 'hard-to-reach' audiences. A random digit dialing telephone survey of 739 Latinos living in two Los Angeles communities was conducted. The relationships between health access difficulties and connections to an integrated storytelling network as well as individual health communication source connections were explored. Findings suggest that Latinos who are connected to an integrated storytelling network report marginally greater ease finding healthcare, despite not being any more likely to have insurance or a regular place for healthcare. Latinos who have health access problems tended to rely more upon Spanish-language television for health information. In addition, those without healthcare access problems are more likely to indicate that they use health professionals, the Internet, mainstream TV and printed materials like health pamphlets for health information. The theoretical and methodological contributions of this work, its major findings, implications, limitations and policy guidelines are discussed.


Assuntos
Educação em Saúde/métodos , Acessibilidade aos Serviços de Saúde , Disparidades nos Níveis de Saúde , Disparidades em Assistência à Saúde/etnologia , Hispânico ou Latino , Adolescente , Adulto , Barreiras de Comunicação , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Los Angeles , Masculino , Pessoas sem Cobertura de Seguro de Saúde/etnologia , Pessoas sem Cobertura de Seguro de Saúde/estatística & dados numéricos , Pessoa de Meia-Idade , Adulto Jovem
12.
J Health Commun ; 16(4): 393-415, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21302173

RESUMO

Combining key ideas from the knowledge-gap hypothesis and communication infrastructure theory, the present study aimed to explain the relations among individuals' education, access to community-based communication resources, and knowledge of chronic diseases (diabetes, hypertension, breast cancer, and prostate cancer) among African Americans and Latinos in Los Angeles. Rather than explore the effect of isolated communication resources, this study explored the effect of an integrated connection to community-based storytellers on chronic disease knowledge. The authors hypothesized that individuals' access to a community-based communication infrastructure for obtaining and sharing information functions as an intervening step in the process where social inequality factors such as education lead to chronic disease knowledge gaps in a local community context. With random samples of African Americans and Latinos in Los Angeles, the authors found that access to community-based communication resources plays a mediating role in the case of breast cancer and diabetes knowledge, but not in hypertension and prostate cancer knowledge. The authors discussed these findings on the basis of communication infrastructure theory and knowledge-gap hypothesis.


Assuntos
Negro ou Afro-Americano/psicologia , Doença Crônica , Conhecimentos, Atitudes e Prática em Saúde , Disparidades nos Níveis de Saúde , Hispânico ou Latino/psicologia , Grupos Minoritários/psicologia , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Serviços de Saúde Comunitária , Escolaridade , Feminino , Comunicação em Saúde , Acessibilidade aos Serviços de Saúde , Hispânico ou Latino/estatística & dados numéricos , Humanos , Los Angeles , Masculino , Pessoa de Meia-Idade , Grupos Minoritários/estatística & dados numéricos , Características de Residência , Apoio Social
13.
Rev Sci Instrum ; 92(2): 023305, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648127

RESUMO

In this paper, we report studies of the Fermi potential and loss per bounce of ultracold neutrons (UCNs) on a deuterated scintillator (Eljen-299-02D). These UCN properties of the scintillator enable its use in a wide variety of applications in fundamental neutron research.

14.
Phys Rev Lett ; 105(18): 181803, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-21231098

RESUMO

A precise measurement of the neutron decay ß asymmetry A0 has been carried out using polarized ultracold neutrons from the pulsed spallation ultracold neutron source at the Los Alamos Neutron Science Center. Combining data obtained in 2008 and 2009, we report A0 = -0.119 66±0.000 89{-0.001 40}{+0.001 23}, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon g{A}/g{V}=-1.275 90{-0.004 45}{+0.004 09}.

15.
Science ; 360(6389): 627-632, 2018 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-29731449

RESUMO

The precise value of the mean neutron lifetime, τn, plays an important role in nuclear and particle physics and cosmology. It is used to predict the ratio of protons to helium atoms in the primordial universe and to search for physics beyond the Standard Model of particle physics. We eliminated loss mechanisms present in previous trap experiments by levitating polarized ultracold neutrons above the surface of an asymmetric storage trap using a repulsive magnetic field gradient so that the stored neutrons do not interact with material trap walls. As a result of this approach and the use of an in situ neutron detector, the lifetime reported here [877.7 ± 0.7 (stat) +0.4/-0.2 (sys) seconds] does not require corrections larger than the quoted uncertainties.

16.
Intern Med J ; 37(11): 775-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17908089

RESUMO

We described two rare severe and fulminant clinical presentations of acute Q fever. The first patient had severe multiorgan failure. The second patient had fever and severe cholera-like diarrhoea. Coxiella burnetii polymerase chain reaction on blood or serum can be clinically useful in the diagnosis of acute Q fever before seroconversion.


Assuntos
Coxiella burnetii , Diarreia/microbiologia , Febre Q/sangue , Febre Q/diagnóstico , Choque Séptico/microbiologia , Adulto , Diarreia/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Febre Q/terapia , Fatores de Risco , Choque Séptico/terapia , Resultado do Tratamento
17.
Rev Sci Instrum ; 88(5): 053508, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28571423

RESUMO

In this paper, we describe a new method for measuring surviving neutrons in neutron lifetime measurements using bottled ultracold neutrons (UCN), which provides better characterization of systematic uncertainties and enables higher precision than previous measurement techniques. An active detector that can be lowered into the trap has been used to measure the neutron distribution as a function of height and measure the influence of marginally trapped UCN on the neutron lifetime measurement. In addition, measurements have demonstrated phase-space evolution and its effect on the lifetime measurement.

18.
Eur J Pain ; 20(9): 1371-83, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27275585

RESUMO

BACKGROUND AND OBJECTIVE: The co-occurrence of chronic pain and post-traumatic stress symptoms (PTSS) and post-traumatic stress disorder (PTSD) has gained increasing research attention. Studies on associations among pain and PTSS or PTSD in youth have largely been conducted in the context of acute injury or trauma. Less is known about the risk for co-occurrence with paediatric chronic pain. In this review, we (1) propose a conceptual framework to outline factors salient during childhood that may be associated with symptom severity, co-occurrence and mutual maintenance, (2) present relevant literature on PTSS in youth with acute and chronic pain and identify research gaps and (3) provide recommendations to guide paediatric research examining shared symptomatology. DATABASES AND DATA TREATMENT: Electronic databases (PubMed and Google Scholar) were used to identify relevant articles using the search terms 'child, adolescent, paediatric, chronic pain, acute pain, post-traumatic stress symptoms and post-traumatic stress disorder'. Studies were retrieved and reviewed based on relevance to the topic. RESULTS: Our findings revealed that existing biobehavioural and ecological models of paediatric chronic pain lack attention to traumatic events or the potential development of PTSS. Paediatric studies are also limited by lack of a conceptual framework for understanding the prevalence, risk and trajectories of PTSS in youth with chronic pain. CONCLUSIONS: Our new developmentally informed framework highlights individual symptoms and shared contextual factors that are important when examining potential associations among paediatric chronic pain and PTSS. Future studies should consider bidirectional and mutually maintaining associations, which will be aided by prospective, longitudinal designs. WHAT DOES THIS REVIEW ADD?: This review presents relevant literature on pain and PTSS in youth and proposes a conceptual framework to examine factors salient during childhood that may be associated with symptom severity, comorbidity and mutual maintenance of chronic pain and PTSS in paediatric populations. We highlight dynamic factors that may change across children's development and provide recommendations to guide paediatric research examining potential associations among PTSS and chronic pain.


Assuntos
Dor Crônica/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Adolescente , Criança , Comorbidade , Feminino , Humanos , Masculino , Prevalência , Estudos Prospectivos , Pesquisa
20.
Rev Sci Instrum ; 86(5): 055101, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26026552

RESUMO

We present the design, description, calibration procedure, and an analysis of systematic effects for an apparatus designed to measure the rotation of the plane of polarization of a transversely polarized slow neutron beam as it passes through unpolarized matter. This device is the neutron optical equivalent of a crossed polarizer/analyzer pair familiar from light optics. This apparatus has been used to search for parity violation in the interaction of polarized slow neutrons in matter. Given the brightness of existing slow neutron sources, this apparatus is capable of measuring a neutron rotary power of dϕ/dz = 1 × 10(-7) rad/m.

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