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1.
Cancer Causes Control ; 32(8): 849-857, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33961148

RESUMO

PURPOSE: To identify staff and participants perspectives of best practices that facilitate achieving enrollment and retention targets in biomedical cohort studies in Caribbean populations. METHODS: Eight focus group discussions (FGDs) were held with research stakeholders including research (i) nurses/study supervisors, (ii) field staff/data collectors, and (iii) rural and urban participants of the Third Jamaica Health and Lifestyle Survey (a national NCD risk factor survey with biospecimen collection) to capture qualitative data on experiences with recruitment, training, retention challenges and potential solutions or strategies for strengthening future efforts. RESULTS: Our findings indicate that trained, experienced study staff with good interpersonal communication skills enhanced the proficiency of field operations and attracted study participants. Targeted community and stakeholder engagement alongside strong support from the coordinating center increased the reach and efficiency of the data collectors. Timely participant feedback, gender-appropriate approaches, and socioeconomic balance enhanced equitable enrollment and retention of participants of cohort studies particularly the hard to reach groups. CONCLUSION: Well-functioning research teams using traditional and social media promotion, applying gender-appropriate and personalized approaches together with strategies for reaching the less accessible socioeconomic groups, are effective for recruiting and retaining members of a Caribbean cohort. These strategies may also enhance the recruitment of other Black populations in the Diaspora including the US and Caribbean into biomedical studies including cancer research.


Assuntos
Pesquisa Biomédica/métodos , População Negra , População Rural , Adulto , Idoso , Idoso de 80 Anos ou mais , Região do Caribe , Estudos de Coortes , Feminino , Grupos Focais , Humanos , Jamaica , Masculino , Pessoa de Meia-Idade , Percepção , Índias Ocidentais , Adulto Jovem
2.
Br J Dermatol ; 184(4): 617-626, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32510579

RESUMO

In order to overcome inconsistencies in the reporting of outcomes in clinical trials, core outcome sets (COSs) have been developed in many clinical areas and the awareness of this concept is growing steadily. The Outcomes for Pressure Ulcer Trials (OUTPUTs) project aims to improve the quality of evidence from pressure ulcer prevention trials by developing a COS. As an initial step in the COS process we aimed to identify and classify both outcomes and concepts that represent potential outcomes for future trials that have been reported in pressure ulcer prevention research. A review was conducted in 12 major databases covering the literature indexed until 2016. Outcomes and relevant concepts reported in primary studies and/or reviews on pressure ulcer prevention in adult patients were extracted as presented in the articles, and afterwards inductively grouped into outcome domains. The domains were then categorized according to the outcome domain taxonomy recently proposed by the COMET group. In total 332 studies were included and 68 outcome domains were identified, covering multiple aspects of pressure ulcer prevention. Pressure ulcer occurrence was reported in 71% of all included studies, representing the most frequent outcome, followed by costs (22% of all studies) and acceptability of intervention and comfort (18% of all studies). A plethora of different outcomes are applied in pressure ulcer prevention research and substantial variations in definitions and reporting of similar outcomes were observed. A COS for pressure ulcer prevention trials is needed to overcome the noncomparability of outcomes.


Assuntos
Úlcera por Pressão , Bases de Dados Factuais , Humanos , Úlcera por Pressão/prevenção & controle , Publicações , Higiene da Pele
3.
Phys Rev Lett ; 123(2): 022501, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386522

RESUMO

We present extractions of the nucleon nonsinglet moments utilizing new precision data on the deuteron F_{2} structure function at large Bjorken-x determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world datasets on the proton and deuteron at lower x measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the x range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high x data. Moreover, recent exciting developments in lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach that first calculates the quark distributions directly before determining moments.

4.
Epidemiol Infect ; 147: e254, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31436145

RESUMO

Frozen raw breaded chicken products (FRBCP) have been identified as a risk factor for Salmonella infection in Canada. In 2017, Canada implemented whole genome sequencing (WGS) for clinical and non-clinical Salmonella isolates, which increased understanding of the relatedness of Salmonella isolates, resulting in an increased number of Salmonella outbreak investigations. A total of 18 outbreaks and 584 laboratory-confirmed cases have been associated with FRBCP or chicken since 2017. The introduction of WGS provided the evidence needed to support a new requirement to control the risk of Salmonella in FRBCP produced for retail sale.


Assuntos
Surtos de Doenças , Conservação de Alimentos , Doenças Transmitidas por Alimentos/epidemiologia , Congelamento , Carne , Infecções por Salmonella/epidemiologia , Animais , Canadá/epidemiologia , Galinhas , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Tipagem Molecular , Salmonella/classificação , Salmonella/genética , Salmonella/isolamento & purificação , Infecções por Salmonella/microbiologia , Sequenciamento Completo do Genoma
5.
Epidemiol Infect ; 146(8): 940-945, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29665871

RESUMO

This research investigates the long-forgotten relationship between diphtheria and tuberculosis. Historical medical reports from the late 19th century are reviewed followed by a statistical regression analysis of the relationship between the two diseases in the early 20th century. Historical medical reports show a consistent association between diphtheria and tuberculosis that can increase the likelihood and severity of either disease in a co-infection. The statistical analysis uses historical weekly public health data on reported cases in five American cities over a period of several years, finding a modest but statistically significant relationship between the two diseases. No current medical theory explains the association between diphtheria and tuberculosis. Alternative explanations are explored with a focus on how the diseases assimilate iron. In a co-infection, the effectiveness of tuberculosis at assimilating extracellular iron may lead to increased production of diphtheria toxin, worsening that disease, which may, in turn, exacerbate tuberculosis. Iron-dependent repressor genes connect both diseases.


Assuntos
Difteria/história , Tuberculose/história , Cidades/epidemiologia , Difteria/epidemiologia , História do Século XIX , História do Século XX , Incidência , Tuberculose/epidemiologia , Estados Unidos/epidemiologia
6.
Ann Oncol ; 28(10): 2581-2587, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961848

RESUMO

BACKGROUND: The BRIM-3 trial showed improved progression-free survival (PFS) and overall survival (OS) for vemurafenib compared with dacarbazine in treatment-naive patients with BRAFV600 mutation-positive metastatic melanoma. We present final OS data from BRIM-3. PATIENTS AND METHODS: Patients were randomly assigned in a 1 : 1 ratio to receive vemurafenib (960 mg twice daily) or dacarbazine (1000 mg/m2 every 3 weeks). OS and PFS were co-primary end points. OS was assessed in the intention-to-treat population, with and without censoring of data for dacarbazine patients who crossed over to vemurafenib. RESULTS: Between 4 January 2010 and 16 December 2010, a total of 675 patients were randomized to vemurafenib (n = 337) or dacarbazine (n = 338, of whom 84 crossed over to vemurafenib). At the time of database lock (14 August 2015), median OS, censored at crossover, was significantly longer for vemurafenib than for dacarbazine {13.6 months [95% confidence interval (CI) 12.0-15.4] versus 9.7 months [95% CI 7.9-12.8; hazard ratio (HR) 0.81 [95% CI 0.67-0.98]; P = 0.03}, as was median OS without censoring at crossover [13.6 months (95% CI 12.0-15.4) versus 10.3 months (95% CI 9.1-12.8); HR 0.81 (95% CI 0.68-0.96); P = 0.01]. Kaplan-Meier estimates of OS rates for vemurafenib versus dacarbazine were 56% versus 46%, 30% versus 24%, 21% versus 19% and 17% versus 16% at 1, 2, 3 and 4 years, respectively. Overall, 173 of the 338 patients (51%) in the dacarbazine arm and 175 of the 337 (52%) of those in the vemurafenib arm received subsequent anticancer therapies, most commonly ipilimumab. Safety data were consistent with the primary analysis. CONCLUSIONS: Vemurafenib continues to be associated with improved median OS in the BRIM-3 trial after extended follow-up. OS curves converged after ≈3 years, likely as a result of crossover from dacarbazine to vemurafenib and receipt of subsequent anticancer therapies. CLINICALTRIALS.GOV: NCT01006980.


Assuntos
Indóis/uso terapêutico , Melanoma/tratamento farmacológico , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/tratamento farmacológico , Sulfonamidas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/enzimologia , Melanoma/genética , Melanoma/mortalidade , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/mortalidade , Resultado do Tratamento , Vemurafenib , Adulto Jovem
7.
Psychol Med ; 47(11): 1880-1892, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28290262

RESUMO

A recent quantitative review in the area of stigma and help seeking in the armed forces has questioned the association between these factors (Sharp et al. 2015). To date, the contribution of qualitative literature in this area has largely been ignored, despite the value this research brings to the understanding of complex social constructs such as stigma. The aim of the current systematic review of qualitative studies was to identify appropriate literature, assess the quality and synthesize findings across studies regarding evidence of stigma-related barriers and facilitators to help seeking for mental health issues within the armed forces. A multi-database text word search incorporating searches of PsycINFO, MEDLINE, Social Policy and Practice, Social Work Abstracts, EMBASE, ERIC and EBM Review databases between 1980 and April 2015 was conducted. Literature was quality assessed using the Critical Appraisal Skills Programme tool. Thematic synthesis was conducted across the literature. The review identified eight studies with 1012 participants meeting the inclusion criteria. Five overarching themes were identified across the literature: (1) non-disclosure; (2) individual beliefs about mental health; (3) anticipated and personal experience of stigma; (4) career concerns; and (5) factors influencing stigma. The findings from the current systematic review found that unlike inconsistent findings in the quantitative literature, there was substantial evidence of a negative relationship between stigma and help seeking for mental health difficulties within the armed forces. The study advocates for refinement of measures to accurately capture the complexity of stigma and help seeking in future quantitative studies.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , Militares/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Estigma Social , Revelação da Verdade , Humanos
8.
J Public Health (Oxf) ; 39(4): e202-e208, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27679656

RESUMO

Background: Non-elite mass participation sports events (MPSEs) may hold potential as a physical activity promotion tool. Research into why people participate in these events and what goals they are pursuing is lacking. Grounded in self-determination theory, this study examined the associations between MPSE participants' goals, event experiences and physical activity. Methods: A prospective cohort study was conducted; pre-event, participants reported their goals for the event. Four weeks post-event, participants reported their motivation for exercise, perceptions of their event achievement and moderate-to-vigorous intensity physical activity (MVPA). Bivariate correlations and path analysis were performed on data from 114 adults. Results: Intrinsic goals (e.g. health, skill and social affiliation) for the event were positively associated with perceptions of event achievement, whereas extrinsic goals (e.g. appearance or social recognition) were not. Event achievement was positively associated with post-event autonomous motivation, which in turn was positively associated with MVPA. Conclusions: Pursuing intrinsic but not extrinsic goals for MPSEs is associated with greater perceptions of event achievement, which in turn is associated with post-event autonomous motivation and MVPA.


Assuntos
Objetivos , Comportamento de Massa , Autonomia Pessoal , Esportes/psicologia , Adulto , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Motivação , Estudos Prospectivos
9.
Genet Mol Res ; 16(1)2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28340271

RESUMO

Fertility traits, such as heifer pregnancy, are economically important in cattle production systems, and are therefore, used in genetic selection programs. The aim of this study was to identify single nucleotide polymorphisms (SNPs) using RNA-sequencing (RNA-Seq) data from ovary, uterus, endometrium, pituitary gland, hypothalamus, liver, longissimus dorsi muscle, and adipose tissue in 62 candidate genes associated with heifer puberty in cattle. RNA-Seq reads were assembled to the bovine reference genome (UMD 3.1.1) and analyzed in five cattle breeds; Brangus, Brahman, Nellore, Angus, and Holstein. Two approaches used the Brangus data for SNP discovery 1) pooling all samples, and 2) within each individual sample. These approaches revealed 1157 SNPs. These were compared with those identified in the pooled samples of the other breeds. Overall, 172 SNPs within 13 genes (CPNE5, FAM19A4, FOXN4, KLF1, LOC777593, MGC157266, NEBL, NRXN3, PEPT-1, PPP3CA, SCG5, TSG101, and TSHR) were concordant in the five breeds. Using Ensembl's Variant Effector Predictor, we determined that 12% of SNPs were in exons (71% synonymous, 29% nonsynonymous), 1% were in untranslated regions (UTRs), 86% were in introns, and 1% were in intergenic regions. Since these SNPs were discovered in RNA, the variants were predicted to be within exons or UTRs. Overall, 160 novel transcripts in 42 candidate genes and five novel genes overlapping five candidate genes were observed. In conclusion, 1157 SNPs were identified in 62 candidate genes associated with puberty in Brangus cattle, of which, 172 were concordant in the five cattle breeds. Novel transcripts and genes were also identified.


Assuntos
Puberdade/genética , Animais , Sequência de Bases , Bovinos , Feminino , Fertilidade/genética , Genoma , Masculino , Polimorfismo de Nucleotídeo Único , Gravidez , RNA/genética , Seleção Genética , Análise de Sequência de RNA/métodos , Maturidade Sexual
10.
BMC Med Res Methodol ; 16(1): 158, 2016 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-27852237

RESUMO

BACKGROUND: Variation in development methods of Pressure Ulcer Risk Assessment Instruments has led to inconsistent inclusion of risk factors and concerns about content validity. A new evidenced-based Risk Assessment Instrument, the Pressure Ulcer Risk Primary Or Secondary Evaluation Tool - PURPOSE-T was developed as part of a National Institute for Health Research (NIHR) funded Pressure Ulcer Research Programme (PURPOSE: RP-PG-0407-10056). This paper reports the pre-test phase to assess and improve PURPOSE-T acceptability, usability and confirm content validity. METHODS: A descriptive study incorporating cognitive pre-testing methods and integration of service user views was undertaken over 3 cycles comprising PURPOSE-T training, a focus group and one-to-one think-aloud interviews. Clinical nurses from 2 acute and 2 community NHS Trusts, were grouped according to job role. Focus group participants used 3 vignettes to complete PURPOSE-T assessments and then participated in the focus group. Think-aloud participants were interviewed during their completion of PURPOSE-T. After each pre-test cycle analysis was undertaken and adjustment/improvements made to PURPOSE-T in an iterative process. This incorporated the use of descriptive statistics for data completeness and decision rule compliance and directed content analysis for interview and focus group data. Data were collected April 2012-June 2012. RESULTS: Thirty-four nurses participated in 3 pre-test cycles. Data from 3 focus groups, 12 think-aloud interviews incorporating 101 PURPOSE-T assessments led to changes to improve instrument content and design, flow and format, decision support and item-specific wording. Acceptability and usability were demonstrated by improved data completion and appropriate risk pathway allocation. The pre-test also confirmed content validity with clinical nurses. CONCLUSIONS: The pre-test was an important step in the development of the preliminary PURPOSE-T and the methods used may have wider instrument development application. PURPOSE-T proposes a new approach to pressure ulcer risk assessment, incorporating a screening stage, the inclusion of skin status to distinguish between those who require primary prevention and those who require secondary prevention/treatment and the use of colour to support pathway allocation and decision making. Further clinical evaluation is planned to assess the reliability and validity of PURPOSE-T and it's impact on care processes and patient outcomes.


Assuntos
Cognição , Medicina Baseada em Evidências/métodos , Úlcera por Pressão/diagnóstico , Inquéritos e Questionários , Adulto , Medicina Baseada em Evidências/estatística & dados numéricos , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Papel do Profissional de Enfermagem , Reprodutibilidade dos Testes , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Adulto Jovem
12.
HIV Med ; 16(10): 640-4, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25958770

RESUMO

OBJECTIVES: The World Health Organization (WHO) recommends screening HIV-infected people for cryptococcal antigens to identify cryptococcosis, a major cause of AIDS-related deaths. As the burden of cryptococcosis is unknown in South Africa's KwaZulu-Natal province, we assessed the cryptococcal antigenuria prevalence among newly diagnosed HIV-infected adults there. METHODS: We conducted a cross-sectional study of newly diagnosed HIV-infected adults who received voluntary HIV testing in an out-patient clinic. Participants provided a urine specimen in a sterile container, and we performed testing with a WHO-endorsed rapid cryptococcal antigen lateral flow assay (Immy Inc., Norman, OK, USA) per the manufacturer's specifications. We assessed cryptococcal antigenuria prevalence among participants with CD4 counts < 200 cells/µL, and stratified results by CD4 count categories. RESULTS: Among 432 participants, the mean (± standard deviation) age was 36.1 ± 9.9 years and 172 (40%) were female. The overall estimated prevalence of cryptococcal antigenuria was 9.0% [95% confidence interval (CI) 6.5-12.1%]. CD4 counts were available for 319 participants (74%); the median CD4 count was 75 cells/µL [interquartile range (IQR) 34-129 cells/µL]. Participants with a negative cryptococcal antigenuria screening test had a median CD4 count of 79 cells/µL (IQR 36-129 cells/µL), while participants with a positive cryptococcal test had a median CD4 count of 41 cells/µL (IQR 10-112 cells/µL). The estimated prevalence of cryptococcal antigenuria among participants with CD4 counts < 50 cells/µL was 12.5% (95% CI 7.0-20.1%), which was significantly higher than that among participants with CD4 counts of 50-200 cells/µL (4.8%; 95% CI 2.3-8.7%). CONCLUSIONS: Nearly 1 in 10 newly diagnosed HIV-infected adults with CD4 counts < 200 cells/µL in KwaZulu-Natal had evidence of cryptococcal antigenuria. Point-of-care CD4 count testing and cryptococcal antigen screening may rapidly identify cryptococcosis at the time of HIV diagnosis.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Antígenos de Fungos/urina , Criptococose/epidemiologia , Cryptococcus/isolamento & purificação , Infecções por HIV/complicações , Adulto , Antígenos de Fungos/sangue , Contagem de Linfócito CD4 , Estudos Transversais , Criptococose/diagnóstico , Criptococose/urina , Cryptococcus/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , África do Sul/epidemiologia
13.
Psychol Med ; 45(11): 2413-25, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25804297

RESUMO

BACKGROUND: Postnatal depression affects about 10-15% of women in the year after giving birth. Many women and healthcare professionals would like an effective and accessible non-pharmacological treatment for postnatal depression. METHOD: Women who fulfilled the International Classification of Diseases (ICD)-10 criteria for major depression in the first 6 months postnatally were randomized to receive usual care plus a facilitated exercise intervention or usual care only. The intervention involved two face-to-face consultations and two telephone support calls with a physical activity facilitator over 6 months to support participants to engage in regular exercise. The primary outcome was symptoms of depression using the Edinburgh Postnatal Depression Scale (EPDS) at 6 months post-randomization. Secondary outcomes included EPDS score as a binary variable (recovered and improved) at 6 and 12 months post-randomization. RESULTS: A total of 146 women were potentially eligible and 94 were randomized. Of these, 34% reported thoughts of self-harming at baseline. After adjusting for baseline EPDS, analyses revealed a -2.04 mean difference in EPDS score, favouring the exercise group [95% confidence interval (CI) -4.11 to 0.03, p = 0.05]. When also adjusting for pre-specified demographic variables the effect was larger and statistically significant (mean difference = -2.26, 95% CI -4.36 to -0.16, p = 0.03). Based on EPDS score a larger proportion of the intervention group was recovered (46.5% v. 23.8%, p = 0.03) compared with usual care at 6 months follow-up. CONCLUSIONS: This trial shows that an exercise intervention that involved encouragement to exercise and to seek out social support to exercise may be an effective treatment for women with postnatal depression, including those with thoughts of self-harming.


Assuntos
Depressão Pós-Parto/terapia , Depressão/terapia , Transtorno Depressivo Maior/terapia , Terapia por Exercício/métodos , Adulto , Feminino , Humanos , Escalas de Graduação Psiquiátrica , Comportamento Autodestrutivo , Apoio Social , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
14.
BJOG ; 122(4): 565-75, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25516405

RESUMO

OBJECTIVE: To investigate the effectiveness of exercise as treatment for vasomotor menopausal symptoms. DESIGN: Three-group randomised controlled trial, two exercise interventions and a control group. SETTING: Primary Care, West Midlands UK. POPULATION: Perimenopausal and postmenopausal women experiencing at least five hot flushes/night sweats per day and not taken MHT in previous 3 months were recruited from 23 general practices. METHODS: Participants in both exercise interventions groups were offered two face-to-face consultations with a physical activity facilitator to support engagement in regular exercise. In addition, one exercise group received a menopause-specific information DVD and written materials to encourage regular exercise and the other exercise group was offered the opportunity to attend exercise social support groups in their communities. Interventions lasted 6 months. MAIN OUTCOME MEASURE: The primary outcome was frequency of hot flushes/night sweats at 6-month up. RESULTS: Two hundred and sixty-one women were randomised (n = 87 per group). Neither of the exercise intervention groups reported significantly less frequent hot flushes/night sweats per week than controls (exercise-DVD versus control: -8.9, 95% CI -20.0 to 2.2; exercise-social support versus control: -5.2, 95% CI -16.7 to 6.3). CONCLUSIONS: This trial indicates that exercise is not an effective treatment for hot flushes/night sweats. Contrary to current clinical guidance, women should not be advised that exercise will relieve their vasomotor menopausal symptoms.


Assuntos
Exercício Físico , Fogachos/prevenção & controle , Menopausa , Feminino , Seguimentos , Humanos , Menopausa/metabolismo , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Atenção Primária à Saúde , Sudorese , Resultado do Tratamento , Reino Unido
15.
Phys Rev Lett ; 112(18): 181801, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24856687

RESUMO

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter θ23. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57×10(20) protons on target, T2K has fit the energy-dependent νµ oscillation probability to determine oscillation parameters. The 68% confidence limit on sin(2)(θ23) is 0.514(-0.056)(+0.055) (0.511±0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Δm32(2)=(2.51±0.10)×10(-3) eV(2)/c(4) (inverted hierarchy: Δm13(2)=(2.48±0.10)×10(-3) eV(2)/c(4)). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

16.
Phys Rev Lett ; 113(24): 241803, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25541766

RESUMO

The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ∼1 GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged ν(e) charged current cross section on carbon is measured to be ⟨σ⟩(ϕ)=1.11±0.10(stat)±0.18(syst)×10⁻³8 cm²/nucleon. The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23×10⁻³8 cm²/nucleon and the GENIE prediction is 1.08×10⁻³8 cm²/nucleon. The total ν(e) charged current cross-section result is also in agreement with data from the Gargamelle experiment.

17.
Phys Rev Lett ; 112(6): 061802, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24580687

RESUMO

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm(32)(2) and a CP violating phase δ(CP). In this neutrino oscillation scenario, assuming |Δm(32)(2)|=2.4×10(-3) eV(2), sin(2)θ(23)=0.5, and Δm322>0 (Δm(32)(2)<0), a best-fit value of sin(2)2θ(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at δ(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of θ(13) from reactor experiments, some values of δ(CP) are disfavored at the 90% C.L.

18.
HIV Clin Trials ; 15(3): 116-25, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24947535

RESUMO

BACKGROUND: Participant attrition in HIV longitudinal studies may introduce bias and diminish research quality. The identification of participant characteristics that are predictive of attrition might inform retention strategies. OBJECTIVE: The study aimed to identify factors associated with attrition among HIV-infected Russian risky drinkers from the secondary HIV prevention HERMITAGE trial. We examined whether current injection drug use (IDU), binge drinking, depressive symptoms, HIV status nondisclosure, stigma, and lifetime history of incarceration were predictors of study attrition. We also explored effect modification due to gender. METHODS: Complete loss to follow-up (LTFU), defined as no follow-up visits after baseline, was the primary outcome, and time to first missed visit was the secondary outcome. We used multiple logistic regression models for the primary analysis, and Cox proportional hazards models for the secondary analysis. RESULTS: Of 660 participants, 101 (15.3%) did not return after baseline. No significant associations between independent variables and complete LTFU were observed. Current IDU and HIV status nondisclosure were significantly associated with time to first missed visit (adjusted hazard ratio [AHR], 1.39; 95% CI, 1.03-1.87; AHR, 1.38; 95% CI, 1.03-1.86, respectively). Gender stratified analyses suggested a larger impact of binge drinking among men and history of incarceration among women with time to first missed visit. CONCLUSIONS: Although no factors were significantly associated with complete LTFU, current IDU and HIV status nondisclosure were significantly associated with time to first missed visit in HIV-infected Russian risky drinkers. An understanding of these predictors may inform retention efforts in longitudinal studies.


Assuntos
Alcoolismo/psicologia , Infecções por HIV/prevenção & controle , Adulto , Depressão/psicologia , Feminino , Seguimentos , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Avaliação de Resultados em Cuidados de Saúde , Federação Russa , Caracteres Sexuais
19.
Caries Res ; 48(4): 306-11, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24557443

RESUMO

Today's fluoride-releasing varnishes (F-varnish) contain a wide variety of ingredients which present analytical challenges for measuring their total fluoride content. This study reports improved methods to measure fluoride content in F-varnishes. Six different commercially available F-varnishes that contain difluorosilane (0.1% F) or NaF (2.26% F) alone or in combination with calcium-phosphates were analyzed. In a vial, 1-3 drops (0.05-0.15 g) of varnish product was dispensed, dissolved in chloroform, equilibrated in TISAB and analyzed via fluoride ion-selective electrode. The average weight percentage of fluoride for all F-varnishes containing NaF ranged from 2.03 to 2.24% F, which is within 90% of the declared label concentration of 2.26% F. Analysis of the difluorosilane-containing product required an additional hydrolysis step. ANOVA found no significant difference between the 5% NaF varnishes at p < 0.05. This method for fluoride analysis yields reliable and reproducible results and can be used for a wide variety of F-varnishes. The standard uncertainty for this method is ±4%. This method may become the basis for national and international standards that ensure the F-varnish products used in clinical practice have the fluoride content declared in the product literature.


Assuntos
Cariostáticos/análise , Fluoretos Tópicos/análise , Fluoretos/análise , Fosfatos de Cálcio/análise , Cariostáticos/química , Caseínas/química , Clorofórmio/química , Fluoretos/química , Fluoretos Tópicos/química , Humanos , Hidrólise , Hidróxidos/química , Eletrodos Seletivos de Íons , Compostos de Potássio/química , Silanos/análise , Fluoreto de Sódio/análise , Solubilidade , Solventes/química
20.
Phys Rev Lett ; 111(21): 211803, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313479

RESUMO

The T2K Collaboration reports a precision measurement of muon neutrino disappearance with an off-axis neutrino beam with a peak energy of 0.6 GeV. Near detector measurements are used to constrain the neutrino flux and cross section parameters. The Super-Kamiokande far detector, which is 295 km downstream of the neutrino production target, collected data corresponding to 3.01×10(20) protons on target. In the absence of neutrino oscillations, 205±17 (syst) events are expected to be detected while only 58 muon neutrino event candidates are observed. A fit to the neutrino rate and energy spectrum, assuming three neutrino flavors and normal mass hierarchy yields a best-fit mixing angle sin2(θ23)=0.514±0.082 and mass splitting |Δm(32)(2)|=2.44(-0.15)(+0.17)×10(-3) eV2/c4. Our result corresponds to the maximal oscillation disappearance probability.

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