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1.
Phys Rev Lett ; 126(1): 012002, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480779

RESUMO

We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer CEvNS over the background-only null hypothesis with greater than 3σ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2±0.7)×10^{-39} cm^{2}-consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the CEvNS process and provides improved constraints on nonstandard neutrino interactions.

2.
Phys Rev Lett ; 124(23): 232502, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32603173

RESUMO

We report on a comparison between the theoretically predicted and experimentally measured spectra of the first-forbidden nonunique ß-decay transition ^{137}Xe(7/2^{-})→^{137}Cs(7/2^{+}). The experimental data were acquired by the EXO-200 experiment during a deployment of an AmBe neutron source. The ultralow background environment of EXO-200, together with dedicated source deployment and analysis procedures, allowed for collection of a pure sample of the decays, with an estimated signal to background ratio of more than 99 to 1 in the energy range from 1075 to 4175 keV. In addition to providing a rare and accurate measurement of the first-forbidden nonunique ß-decay shape, this work constitutes a novel test of the calculated electron spectral shapes in the context of the reactor antineutrino anomaly and spectral bump.

3.
Phys Rev Lett ; 123(16): 161802, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31702371

RESUMO

A search for neutrinoless double-ß decay (0νßß) in ^{136}Xe is performed with the full EXO-200 dataset using a deep neural network to discriminate between 0νßß and background events. Relative to previous analyses, the signal detection efficiency has been raised from 80.8% to 96.4±3.0%, and the energy resolution of the detector at the Q value of ^{136}Xe 0νßß has been improved from σ/E=1.23% to 1.15±0.02% with the upgraded detector. Accounting for the new data, the median 90% confidence level 0νßß half-life sensitivity for this analysis is 5.0×10^{25} yr with a total ^{136}Xe exposure of 234.1 kg yr. No statistically significant evidence for 0νßß is observed, leading to a lower limit on the 0νßß half-life of 3.5×10^{25} yr at the 90% confidence level.

4.
Phys Rev Lett ; 120(7): 072701, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29542972

RESUMO

Results from a search for neutrinoless double-beta decay (0νßß) of ^{136}Xe are presented using the first year of data taken with the upgraded EXO-200 detector. Relative to previous searches by EXO-200, the energy resolution of the detector has been improved to σ/E=1.23%, the electric field in the drift region has been raised by 50%, and a system to suppress radon in the volume between the cryostat and lead shielding has been implemented. In addition, analysis techniques that improve topological discrimination between 0νßß and background events have been developed. Incorporating these hardware and analysis improvements, the median 90% confidence level 0νßß half-life sensitivity after combining with the full data set acquired before the upgrade has increased twofold to 3.7×10^{25} yr. No statistically significant evidence for 0νßß is observed, leading to a lower limit on the 0νßß half-life of 1.8×10^{25} yr at the 90% confidence level.

5.
Nature ; 460(7253): 384-7, 2009 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-19606148

RESUMO

In recent years, strikingly consistent patterns of biodiversity have been identified over space, time, organism type and geographical region. A neutral theory (assuming no environmental selection or organismal interactions) has been shown to predict many patterns of ecological biodiversity. This theory is based on a mechanism by which new species arise similarly to point mutations in a population without sexual reproduction. Here we report the simulation of populations with sexual reproduction, mutation and dispersal. We found simulated time dependence of speciation rates, species-area relationships and species abundance distributions consistent with the behaviours found in nature. From our results, we predict steady speciation rates, more species in one-dimensional environments than two-dimensional environments, three scaling regimes of species-area relationships and lognormal distributions of species abundance with an excess of rare species and a tail that may be approximated by Fisher's logarithmic series. These are consistent with dependences reported for, among others, global birds and flowering plants, marine invertebrate fossils, ray-finned fishes, British birds and moths, North American songbirds, mammal fossils from Kansas and Panamanian shrubs. Quantitative comparisons of specific cases are remarkably successful. Our biodiversity results provide additional evidence that species diversity arises without specific physical barriers. This is similar to heavy traffic flows, where traffic jams can form even without accidents or barriers.


Assuntos
Biodiversidade , Especiação Genética , Reprodução/fisiologia , Animais , Transtornos do Desenvolvimento Sexual , Extinção Biológica , Genótipo , Haploidia , Modelos Biológicos , Mutação/genética , Dinâmica Populacional , Reprodução/genética , Comportamento Sexual Animal , Fatores de Tempo
6.
Int J Clin Pract ; 69(3): 358-65, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25648652

RESUMO

BACKGROUND AND AIMS: The aim of this study was to assess prevalence and associated bother of male lower urinary tract symptoms (LUTS), especially of urgency and other storage symptoms, since these are generally assumed to be underdiagnosed/undertreated in men. METHODS: Data on bladder condition of men ≥ 40 years were prospectively collected by 124 general practitioners (GPs) during a regular visit for any reason, using the validated ICIQ-MLUTS questionnaire. For 13 symptoms, prevalence (scale 0-4) and bother (scale 0-10) were scored. General bladder-related quality of life (scale 0-3) was also assessed. RESULTS: Data from 5890 men (mean age: 61.2 years) were analysed. A total of 7.7% had urgency most or all of the time (score ≥ 3) and 6.2% had bothersome urgency (score ≥ 3 + bother score ≥ 5). Nocturia (69.2%) and urgency (58.3%) were the most prevalent and bothersome symptoms. Both prevalence and bother of all LUTS increased with age. Additionally, 28.9% of men reported to be a little bothered by their bladder condition in everyday life, while 11.9% were bothered a lot/very much (2.5% in age group 40-49 years increasing to 29.2% in those > 80 years). CONCLUSIONS: In the general population of men ≥ 40 years who visited a GP for any reason, 41% indicated to be at least a little bothered by their bladder condition. The prevalence of LUTS, especially nocturia and urgency, is high and a significant number of men indicated to be seriously bothered. Increasing awareness of male LUTS, and storage symptoms in particular, is warranted to discuss management options that could increase quality of life.


Assuntos
Sintomas do Trato Urinário Inferior/epidemiologia , Qualidade de Vida , Inquéritos e Questionários , Micção/fisiologia , Adulto , Idoso , Bélgica/epidemiologia , Humanos , Sintomas do Trato Urinário Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Reprodutibilidade dos Testes
7.
Ophthalmic Genet ; 45(2): 207-209, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37722826

RESUMO

BACKGROUND: We present a case of a child with Floating-Harbor Syndrome (FHS) with bilateral chorioretinal coloboma (CC). To the best of our knowledge, this is the first case report of this association. Floating- Harbor syndrome is an extremely rare autosomal dominant genetic disorder with approximately 100 cases reported. It is characterized by a series of atypical features that include short stature with delayed bone age, low birth weight, skeletal anomalies, delayed speech development, and dysmorphic facial characteristics that typically portray a triangular face, deep-set eyes, long eyelashes, and prominent nose. MATERIALS AND METHODS: Our patient was examined by a pediatric ophthalmologist for the time at age of 7. Visual acuity, optical coherence tomography (OCT) and Optos imaging were collected on every visit. The patient had whole genome sequencing ordered by a pediatric geneticist to confirm Floating-Harbor syndrome. RESULTS: We present the patient's OCT and Optos images that illustrate the location of the patient's inferior chorioretinal coloboma in both eyes. The whole genome sequencing report collected revealed a heterozygous de novo pathogenic variant in the SRCAP gene, consistent with a Floating-Harbor syndrome diagnosis in the literature. DISCUSSION: Both genetic and systemic findings are consistent with the diagnosis of Floating-Harbor syndrome in our patient. Rubenstein-Taybi and Floating-Harbor syndrome share a similarity in molecular and physical manifestations, but because of the prevalence in Rubenstein-Taybi diagnoses, it is a syndromic condition that includes coloboma and frequently associated with each other. Therefore, a retinal exam should become part of the standard protocol for those with FHS, as proper diagnosis, examination and treatment can prevent irreversible retinal damage.


Assuntos
Anormalidades Múltiplas , Coloboma , Anormalidades Craniofaciais , Comunicação Interventricular , Humanos , Criança , Coloboma/diagnóstico , Coloboma/genética , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/diagnóstico , Anormalidades Craniofaciais/diagnóstico , Anormalidades Craniofaciais/genética , Transtornos do Crescimento/diagnóstico , Transtornos do Crescimento/genética
8.
Int J Clin Pract ; 67(3): 198-204, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23409688

RESUMO

AIM: This Belgian epidemiological study aimed to assess the prevalence of overactive bladder (OAB) and stress urinary incontinence (SUI) and associated bother in a female primary care population. METHODS: Data on OAB and SUI were prospectively collected among women ≥ 40 years by general practitioners (GP) during a regular visit for any reason. The validated Bladder Control Self-Assessment Questionnaire (B-SAQ) was used and complemented with a question on SUI and bladder bother. The presence of mild bladder control symptoms (BCS) was defined as an overall B-SAQ symptom score (OSS) ≥ 4 and an overall bother score (OBS) ≥ 1. Descriptive statistics were performed. RESULTS: Data from 7139 women were analysed. About 33.9% had mild BCS. Most women reported overall mild OAB symptoms (46.9%) and 34.9% had moderate-to-(very) severe symptoms. The prevalence of moderate-severe urgency, frequency or nocturia was higher than that of moderate-severe incontinence. Urgency and nocturia were considered the most bothersome symptoms. Moderate-severe SUI affected 17.7% of women. About 16.4% of women reported to be moderately-severely bothered by their bladder in everyday life. The risk of severe symptoms and bother increased with age. About 10% of women had clinically significant BCS (OSS ≥ 7 and OBS ≥ 4). CONCLUSIONS: In Belgian women ≥ 40 years visiting a GP for any reason, one in three had mild BCS and might benefit from further evaluation. Up to 10% of these women had clinically significant BCS for which medical therapy might be necessary. This warrants awareness for early diagnosis and intervention.


Assuntos
Bexiga Urinária Hiperativa/epidemiologia , Incontinência Urinária por Estresse/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Bélgica/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco
9.
Phys Rev Lett ; 109(3): 032505, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22861843

RESUMO

We report on a search for neutrinoless double-beta decay of 136Xe with EXO-200. No signal is observed for an exposure of 32.5 kg yr, with a background of ∼1.5×10(-3) kg(-1) yr(-1) keV(-1) in the ±1σ region of interest. This sets a lower limit on the half-life of the neutrinoless double-beta decay T(1/2)(0νßß)(136Xe)>1.6×10(25) yr (90% C.L.), corresponding to effective Majorana masses of less than 140-380 meV, depending on the matrix element calculation.

10.
Phys Rev Lett ; 107(26): 262501, 2011 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-22243152

RESUMO

The (2)H(e,e'p)n cross section at a momentum transfer of 3.5 (GeV/c)(2) was measured over a kinematical range that made it possible to study this reaction for a set of fixed missing momenta as a function of the neutron recoil angle θ(nq) and to extract missing momentum distributions for fixed values of θ(nq) up to 0.55 GeV/c. In the region of 35°≤θ(nq)≤45° recent calculations, which predict that final-state interactions are small, agree reasonably well with the experimental data. Therefore, these experimental reduced cross sections provide direct access to the high momentum component of the deuteron momentum distribution in exclusive deuteron electrodisintegration.

11.
Diabetologia ; 53(4): 614-23, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20225393

RESUMO

AIMS/HYPOTHESIS: The aim of the study was to examine the 48 month outcome of treating recent-onset type 1 diabetic patients for 6 days with humanised CD3-antibody, ChAglyCD3. METHODS: Eighty patients, aged 12-39 years, were recruited for a phase 2 multicentre trial and randomised to placebo (n=40) or ChAglyCD3 (n=40) treatment by a third party member; participants and care-givers were blinded. The change in insulin dose (U kg(-1)day(-1)) over 48 months was chosen as primary endpoint and compared in 31 placebo-and 33 ChAglyCD3-treated patients. Adverse events were followed in 35 and 38 patients, respectively. RESULTS: Treatment with ChAglyCD3 delayed the rise in insulin requirements of patients with recent-onset diabetes and reduced its amplitude over 48 months (+0.09 vs +0.32 U kg(-1)day(-1) in the placebo group). Using multivariate analysis this effect was correlated with higher baseline residual beta cell function and a younger age. It was associated with better outcome variables in subgroups selected according to these variables. In the ChAglyCD3 subgroup with higher initial beta cell function, 0/11 patients became C-peptide-negative over 48 months vs 4/9 in the corresponding placebo subgroup. In the subgroup aged <27 years old, antibody treatment preserved initial beta cell function for 36 months (vs >80% decline within 24 months in the placebo subgroup <27 years old), resulted in lower HbA1c concentrations and tended to reduce glycaemic variability (p=0.08). No longterm adverse events were observed. CONCLUSIONS/INTERPRETATION: A 6 day ChAglyCD3 treatment can suppress the rise in insulin requirements of recent-onset type 1 diabetic patients over 48 months, depending on their age and initial residual beta cell function. In younger patients this effect is associated with reduced deterioration of metabolic variables. These observations help to define inclusion criteria for prevention trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT00627146 FUNDING: Center grants from the Juvenile Diabetes Research Foundation (4-2001-434, 4-2005-1327) and grants from the Belgian Fund for Scientific Research-Flanders and from Brussels Free University-VUB.


Assuntos
Anticorpos/uso terapêutico , Complexo CD3/imunologia , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/fisiologia , Adulto , Fatores Etários , Bélgica , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Seguimentos , Hemoglobinas Glicadas/metabolismo , Humanos , Subpopulações de Linfócitos/imunologia , Masculino , Placebos , Sistema de Registros , Fatores de Tempo , Adulto Jovem
12.
Phys Rev Lett ; 103(20): 202501, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-20365979

RESUMO

An experimental study of the (16)O(e,e'K(+))(Lambda)(16)N reaction has been performed at Jefferson Lab. A thin film of falling water was used as a target. This permitted a simultaneous measurement of the p(e,e'K(+))Lambda, Sigma(0) exclusive reactions and a precise calibration of the energy scale. A ground-state binding energy of 13.76+/-0.16 MeV was obtained for (Lambda)(16)N with better precision than previous measurements on the mirror hypernucleus (Lambda)(16)O. Precise energies have been determined for peaks arising from a Lambda in s and p orbits coupled to the p(1/2) and p(3/2) hole states of the (15)N core nucleus.

13.
Science ; 216(4552): 1339-40, 1982 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-7079770

RESUMO

Neuromagnetic measurements of responses to auditory stimuli consisting of pure tones amplitude-modulated at a low frequency have been used to deduce the location of cortical activity. The evoked field source systematically increased in depth beneath the scalp with increasing frequency of the tone. The tonotopic progression can be described as a logarithmic mapping.


Assuntos
Córtex Auditivo/fisiologia , Estimulação Acústica , Córtex Auditivo/anatomia & histologia , Potenciais Evocados , Potenciais Evocados Auditivos , Humanos , Magnetismo
14.
Science ; 258(5088): 1668-70, 1992 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-1455246

RESUMO

Noninvasive magnetoencephalography makes it possible to identify the cortical area in the human brain whose activity reflects the decay of passive sensory storage of information about auditory stimuli (echoic memory). The lifetime for decay of the neuronal activation trace in primary auditory cortex was found to predict the psychophysically determined duration of memory for the loudness of a tone. Although memory for the loudness of a specific tone is lost, the remembered loudness decays toward the global mean of all of the loudnesses to which a subject is exposed in a series of trials.


Assuntos
Córtex Auditivo/fisiologia , Córtex Cerebral/fisiologia , Audição , Memória , Neurônios/fisiologia , Estimulação Acústica , Humanos , Magnetoencefalografia
15.
Science ; 220(4604): 1394-6, 1983 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-6857258

RESUMO

Gel filtration of serum at pH 3.6 yielded a fraction that supported long-term (months) survival of dissociated rat central neurons in monolayer culture more reliably than the traditionally used unfractionated serum. The cultures remained neuron-rich, because this fraction did not support the proliferation of glia and fibroblasts that occurs in whole serum. With an apparent molecular weight of 55,000 and an isoelectric point of 5.6, the active factor (or factors) in this fraction is distinct from any well-defined growth factor.


Assuntos
Sobrevivência Celular , Fatores de Crescimento Neural/farmacologia , Neurônios/fisiologia , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia em Gel , Cavalos , Focalização Isoelétrica , Peso Molecular , Fatores de Crescimento Neural/isolamento & purificação , Neurônios/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Medula Espinal/citologia
16.
Science ; 190(4213): 480-2, 1975 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-170683

RESUMO

Magnetic field variations from the human brain produced by visual stimulation have been observed in a normal laboratory setting with a superconducting quantum interference device and no magnetic shielding of the subject. Previously unknown temporal and spatial features of the field near the scalp are reported.


Assuntos
Encéfalo/fisiologia , Magnetismo , Vias Visuais/fisiologia , Humanos , Condução Nervosa , Transmissão Sináptica , Fatores de Tempo
17.
Science ; 170(3955): 320-2, 1970 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-5460517

RESUMO

The excessive induction of hepatic delta-aminolevulinic acid synthetase in rats after the administration of porphyria-inducing compounds is prevented by prior treatment with phenobarbital. Studies in vivo and in vitro indicate that phenobarbital prevents the induction of chemical porphyria by increasing the rate of detoxification of inducers by way of drug-metabolizing enzymes of the hepatic endoplasmic reticulum.


Assuntos
Aciltransferases/biossíntese , Retículo Endoplasmático/enzimologia , Indução Enzimática/efeitos dos fármacos , Fígado/enzimologia , Fenobarbital/uso terapêutico , Porfirias/induzido quimicamente , Porfirias/tratamento farmacológico , Amidas , Aminoácidos , Animais , Biotransformação , Isótopos de Carbono , Cromatografia em Camada Fina , Feminino , Ácidos Levulínicos/biossíntese , Fígado/citologia , Microssomos Hepáticos/metabolismo , Progesterona , Ratos , Succinatos/biossíntese
18.
Science ; 226(4681): 1447-9, 1984 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-17789001

RESUMO

For several species of plants the abundance of those transcripts encoding the chlorophyll a/b binding protein (cab RNA) and the small subunit of ribulose-1,5-biphosphate carboxylase-oxygenase (rbcS RNA) has been established as being under the control of phytochrome. However, this conclusion does not take into account the various types of phytochrome control based on both the fluence of red light necessary to induce the response and the ability of far red light either to induce or to reverse the response. The fluence of red light necessary to induce the accumulation of rbcS RNA was found to be 10,000 times greater than that necessary to induce the accumulation of cab RNA. Furthermore, far red light alone was capable of inducing the accumulation of cab RNA. It is possible, therefore, that developing pea buds accumulate cab RNA before rbcS and that cab RNA is not subject to the normal end-of-day signals affecting many phytochrome responses.

19.
Science ; 199(4324): 81-3, 1978 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-17569490

RESUMO

The human brain is found to produce a magnetic field near the scalp which varies in synchrony with periodic electrical stimulation applied to a finger. Use of a highly sensitive superconducting quantum interference device as a magnetic field detector reveals that the brain's field is sharply localized over the primary projection area of the sensory cortex contralateral to the digit being stimulated. The phase of the response at the stimulus frequency varies monotonically with the repetition rate and at intermediate frequencies yields a latency of approximately 70 milliseconds for cortical response.


Assuntos
Encéfalo/fisiologia , Campos Eletromagnéticos , Adulto , Mapeamento Encefálico , Estimulação Elétrica , Dedos , Humanos , Masculino , Tempo de Reação , Polegar
20.
Science ; 214(4522): 749-55, 1981 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-17744383

RESUMO

Coral reefs of north Jamaica, normally sheltered, were severely damaged by Hurricane Allen, the strongest Caribbean hurricane of this century. Immediate studies were made at Discovery Bay, where reef populations were already known in some detail. Data are presented to show how damage varied with the position and orientation of the substraturn and with the shape, size, and mechanical properties of exposed organisms. Data collected over succeeding weeks showed striking differences in the ability of organisms to heal and survive.

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