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1.
Rev Sci Instrum ; 88(8): 083503, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28863637

RESUMO

We describe an apparatus used to measure the electron-antineutrino angular correlation coefficient in free neutron decay. The apparatus employs a novel measurement technique in which the angular correlation is converted into a proton time-of-flight asymmetry that is counted directly, avoiding the need for proton spectroscopy. Details of the method, apparatus, detectors, data acquisition, and data reduction scheme are presented, along with a discussion of the important systematic effects.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31092963

RESUMO

Backscatter of electrons from a beta spectrometer, with incomplete energy deposition, can lead to undesirable effects in many types of experiments. We present and discuss the design and operation of a backscatter-suppressed beta spectrometer that was developed as part of a program to measure the electronantineutrino correlation coefficient in neutron beta decay (aCORN). An array of backscatter veto detectors surrounds a plastic scintillator beta energy detector. The spectrometer contains an axial magnetic field gradient, so electrons are efficiently admitted but have a low probability for escaping back through the entrance after backscattering. The design, construction, calibration, and performance of the spectrometer are discussed.

3.
Phys Rev Lett ; 119(4): 042502, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-29341742

RESUMO

We report the first result for the electron-antineutrino angular correlation (a coefficient) in free neutron ß decay from the aCORN experiment. aCORN uses a novel method in which the a coefficient is proportional to an asymmetry in proton time of flight for events where the ß electron and recoil proton are detected in delayed coincidence. Data are presented from a 15 month run at the NIST Center for Neutron Research. We obtained a=-0.1090±0.0030(stat)±0.0028(sys), the most precise measurement of the neutron a coefficient reported to date.

4.
J Dev Orig Health Dis ; 7(3): 273-281, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26880155

RESUMO

Maternal smoking during pregnancy is associated with both reduced birth weight and adverse neurobehavioral outcomes. The aim of this study was to investigate longitudinal associations between maternal smoking during pregnancy and childhood behavioral outcomes, and to determine the role of birth weight in mediating such associations. The study included 489 mother-child pairs. Prenatal exposures were assessed via maternal interviews conducted on average 1 year after delivery and child behavior assessments were completed at 5-12 years of age using the Child Behavior Checklist (CBCL) and Teacher Report Form (TRF). Maternal smoking during pregnancy was associated with externalizing and total behavior problems according to both mother and teacher report. Maternal smoking was also associated with the following percentage increases in scores: 41% (CBCL) and 44% (TRF) for aggressive behavior and 65% (CBCL) and 47% (TRF) for attention problems. Associations with behavior problems were attenuated or no longer observed for mothers that quit smoking in early pregnancy. The proportion of the total effect of maternal smoking on behavioral outcomes explained by differences in birth weight was small and ranged from 6.6% for externalizing behavior on the CBCL to 20.1% for rule-breaking behavior on the CBCL. Our results suggest that birth weight differences explain only a small proportion of the magnitude of association between maternal smoking during pregnancy and selected behavioral outcomes.

6.
Cleft Palate Craniofac J ; 47(4): 368-77, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20590458

RESUMO

OBJECTIVE: The authors developed and tested three-dimensional (3D) indices for quantifying the severity of deformational plagiocephaly (DP). DESIGN: The authors evaluated the extent to which infants with and without DP (as determined by clinic referral and two experts' ratings) could be correctly classified. PARTICIPANTS: Infants aged 4 to 11 months, including 154 with diagnosed DP and 100 infants without a history of DP or other craniofacial condition. After excluding participants with discrepant expert ratings, data from 90 infants with DP and 50 infants without DP were retained. MEASUREMENTS: Two-dimensional (2D) histograms of surface normal vector angles were extracted from 3D mesh data and used to compute the severity scores. OUTCOME MEASURES: Left posterior flattening score (LPFS), right posterior flattening score (RPFS), asymmetry score (AS), absolute asymmetry score (AAS), and an approximation of a previously described 2D measure, the oblique cranial length ratio (aOCLR). Two-dimensional histograms localized the posterior flatness for each participant. ANALYSIS: The authors fit receiver operating characteristic curves and calculated the area under the curves (AUC) to evaluate the relative accuracy of DP classification using the above measures. RESULTS: The AUC statistics were AAS = 91%, LPFS = 97%, RPFS = 91%, AS = 99%, and aOCLR = 79%. CONCLUSION: Novel 3D-based plagiocephaly posterior severity scores provided better sensitivity and specificity in the discrimination of plagiocephalic and typical head shapes than the 2D measurements provided by a close approximation of OCLR. These indices will allow for more precise quantification of the DP phenotype in future studies on the prevalence of this condition, which may lead to improved clinical care.


Assuntos
Modelos Anatômicos , Plagiocefalia não Sinostótica/classificação , Área Sob a Curva , Feminino , Humanos , Lactente , Masculino , Índice de Gravidade de Doença
7.
Curr Med Res Opin ; 26(5): 1231-45, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20337502

RESUMO

BACKGROUND: Although chronic pain affects around 20% of adults in Europe and the USA, there is substantial evidence that it is inadequately treated. In June 2009, an international group of pain specialists met in Brussels to identify the reasons for this and to achieve consensus on strategies for improving pain management. SCOPE: Literature on chronic pain management was reviewed, and information presented to and discussed by a panel of experts. FINDINGS: It was agreed that guidelines are not universally accepted by those involved in pain management, and pain treatment seems to be driven mainly by tradition and personal experience. Other factors include poor communication between patients and physicians, the side effects of analgesic drugs, and limited individualisation of therapy. Difficulty in maintaining the balance between adequate pain relief and acceptable tolerability, particularly with strong opioids, can lead to the establishment of a 'vicious circle' that alternates between lack of efficacy and unpleasant side effects, prompting discontinuation of treatment. The medical community's understanding of the physiological differences between nociceptive pain and neuropathic pain, which is often more severe and difficult to treat, could be improved. Increasing physicians' knowledge of the pharmacological options available to manage these different pain mechanisms offers the promise of better treatment decisions and more widespread adoption of a multi-mechanistic approach; this could involve loosely combining two substances from different drug classes, or administering an analgesic with two different mechanisms of action. In some circumstances, a single compound capable of addressing both nociceptive and neuropathic pain is desirable. CONCLUSIONS: To improve patient outcomes, a thorough understanding of pain mechanisms, sensitisation and multi-mechanistic management is required. Universal, user-friendly educational tools are therefore required to familiarise physicians with these topics, and also to improve communication between physicians and their pain patients, so that realistic expectations of treatment can be established.


Assuntos
Analgésicos/uso terapêutico , Dor/tratamento farmacológico , Doença Crônica , Humanos , Guias de Prática Clínica como Assunto
8.
Ann Oncol ; 20(8): 1420-33, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19244085

RESUMO

BACKGROUND: The European Pain in Cancer survey sought to increase understanding of cancer-related pain and treatment across Europe. PATIENTS AND METHODS: Patients with all stages of cancer participated in a two-phase telephone survey conducted in 11 European countries and Israel in 2006-2007. The survey screened for patients experiencing pain at least weekly, then randomly selected adult patients with pain of at least moderate intensity occurring several times per week for the last month completed a detailed attitudinal questionnaire. RESULTS: Of 5084 adult patients contacted, 56% suffered moderate-to-severe pain at least monthly. Of 573 patients randomly selected for the second survey phase, 77% were receiving prescription-only analgesics, with 41% taking strong opioids either alone or with other drugs for cancer-related pain. Of those prescribed analgesics, 63% experienced breakthrough pain. In all, 69% reported pain-related difficulties with everyday activities; however, 50% believed that their quality of life was not considered a priority in their overall care by their health care professional. CONCLUSIONS: Across Europe and Israel, treatment of cancer pain is suboptimal. Pain and pain relief should be considered integral to the diagnosis and treatment of cancer; management guidelines should be revised to improve pain control in patients with cancer.


Assuntos
Neoplasias/complicações , Dor/tratamento farmacológico , Dor/etiologia , Analgésicos Opioides/administração & dosagem , Atitude , Coleta de Dados , Europa (Continente)/epidemiologia , Feminino , Humanos , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Dor/epidemiologia , Prevalência , Qualidade de Vida , Resultado do Tratamento
9.
Clin Med (Lond) ; 7(5): 496-500, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17990720

RESUMO

Pain is under-recognised and under-treated in older people. It is a subjective, personal experience, only known to the person who suffers. The assessment of pain is particularly challenging in the presence of severe cognitive impairment, communication difficulties or language and cultural barriers. These guidelines set out the key components of assessing pain in older people, together with a variety of practical scales that may be used with different groups, including those with varying levels of cognitive or communication impairment. The purpose is to provide professionals with a set of practical skills to assess pain as the first step towards its effective management. The guidance has implications for all healthcare and social care staff and can be applied in all settings, including the older person's own home, in care homes, and in hospital.


Assuntos
Transtornos Cognitivos , Cognição , Avaliação Geriátrica , Dor/diagnóstico , Percepção , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comunicação , Humanos , Dor/fisiopatologia , Dor/psicologia , Medição da Dor , Relações Médico-Paciente , Guias de Prática Clínica como Assunto
10.
Orthod Craniofac Res ; 10(3): 138-48, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17651130

RESUMO

The mental health of children, adolescents, and adults with orofacial clefts has been studied extensively. Outcomes of interest have included parental adaptation, parent-child attachment, child development, intellectual and academic outcomes, behavioral adaptation, and quality of life. The literature sheds light on mental health needs and opportunities in each of these domains at various stages of development. However, this research has been limited in several respects and methodologically rigorous studies are needed to clarify the role of mental health in craniofacial team care. In particular, randomized controlled trials investigating the efficacy of psychosocial interventions tailored for this population are long overdue. Such studies have the potential to advance routine mental health care for individuals with orofacial clefts to the level of 'evidence-based care.'


Assuntos
Desenvolvimento Infantil/fisiologia , Fenda Labial/psicologia , Fissura Palatina/psicologia , Saúde Mental , Adolescente , Comportamento do Adolescente , Criança , Comportamento Infantil , Pré-Escolar , Humanos , Relações Pais-Filho
11.
J Res Natl Inst Stand Technol ; 110(4): 401-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-27308157

RESUMO

Currently, the beta-neutrino asymmetry has the largest uncertainty (4 %) of the neutron decay angular correlations. Without requiring polarimetry this decay parameter can be used to measure λ (ga/gv ), test Cabibbo-Kobayashi-Maskawa (CKM) unitarity limit scalar and tensor currents, and search for Charged Vector Current (CVC) violation. We propose to measure the beta-neutrino asymmetry coeffcient, a, using time-of-flight for the recoil protons. We hope to achieve a systematic uncertainty of σa / a ≈ 1.0 %. After tests at Indiana University's Low Energy Neutron Source (LENS), the apparatus will be moved to the National Institute of Standards and Technology (NIST) where the measurement can achieve a statistical uncertainty of 1 % to 2 % in about 200 beam days.

14.
Artigo em Inglês | MEDLINE | ID: mdl-10962641

RESUMO

Chronic pelvic pain can be a perplexing and complex problem, frustrating to both clinicians and patients. The traditional medical and surgical model does not always relieve symptoms, and many patients suffer years of pain and undergo multiple surgical procedures without long-term benefit. The biopsychosocial model for chronic pelvic pain gives clinicians the opportunity to broaden the scope for management. A multidisciplinary team can offer simultaneous assessment and management of somatic, behavioural and psychosocial components of the pain. Key members of the team are identified and their roles explored. Practical aspects of operating a multidisciplinary clinic are discussed. A multidisciplinary approach comprises many elements. Further research is needed to identify which are the essential elements to secure optimum outcome for the individual patient.


Assuntos
Clínicas de Dor/organização & administração , Equipe de Assistência ao Paciente/organização & administração , Dor Pélvica/terapia , Doença Crônica , Feminino , Humanos , Resultado do Tratamento
16.
Br J Obstet Gynaecol ; 105(1): 87-92, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9442168

RESUMO

OBJECTIVE: To investigate and compare the demographic and psychosocial profiles of women with chronic pelvic pain, chronic pain in a different site, and those with no history of pain with specific reference to a history of sexual abuse. DESIGN: A prospective comparative study. SETTING: Pelvic Pain Clinic at Leicester General Hospital NHS Trust, Pain Management Clinic at Leicester Royal Infirmary NHS Trust and two General Practices. PARTICIPANTS: Thirty women with chronic pelvic pain, 30 women with chronic pain in a different site and 30 women attending their general practitioner with no history of pain. INTERVENTIONS: A specifically designed patient profile questionnaire to identify and explore incidents of sexual and physical abuse was administered to each woman by a research psychologist for confidential self-completion. Data were also collected on other demographic, medical and psychosocial characteristics. RESULTS: Women with chronic pelvic pain were found to have a higher lifetime prevalence of sexual abuse, involving penetration or other genital contact compared with the two comparison groups. The prevalence of physical abuse was the same in all groups. Women in the pelvic pain group were more likely to have approached their GP for symptoms not related to pelvic pain than women in the other two groups and the incidence of clinical anxiety was significantly higher in this group compared with the pain-free group. The prevalence of sexual problems was much higher in the group with pelvic pain compared with the other two groups. CONCLUSION: These findings indicate that women with chronic pelvic pain have a higher incidence of past sexual abuse compared with women in a comparison pain group and with women with no pain.


Assuntos
Dor/etiologia , Doença Inflamatória Pélvica/etiologia , Adolescente , Adulto , Doença Crônica , Medicina de Família e Comunidade , Feminino , Humanos , Ciclo Menstrual , Pessoa de Meia-Idade , Dor/psicologia , Aceitação pelo Paciente de Cuidados de Saúde , Doença Inflamatória Pélvica/psicologia , Estudos Prospectivos , Características de Residência , Comportamento Sexual , Assédio Sexual , Transtornos Somatoformes/psicologia
18.
J Forensic Sci ; 39(5): 1182-7, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7964561

RESUMO

Replacement of the myocardium by fibrous and adipose tissue is well documented in the right ventricle, but has been rarely described in the left ventricle. We present two cases of extensive fibrofatty infiltration of the left ventricle without significant right ventricular involvement in young men whose presenting symptom was sudden death.


Assuntos
Tecido Adiposo/patologia , Morte Súbita Cardíaca/etiologia , Ventrículos do Coração/patologia , Adulto , Morte Súbita Cardíaca/patologia , Fibrose/patologia , Ventrículos do Coração/anormalidades , Humanos , Masculino
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