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1.
Phys Rev Lett ; 119(18): 182501, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29219591

RESUMO

We report the measurement of the beam-vector and tensor asymmetries A_{ed}^{V} and A_{d}^{T} in quasielastic (e[over →],e^{'}p) electrodisintegration of the deuteron at the MIT-Bates Linear Accelerator Center up to missing momentum of 500 MeV/c. Data were collected simultaneously over a momentum transfer range 0.1

2.
Phys Rev Lett ; 107(25): 252501, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22243068

RESUMO

We report a precision measurement of the deuteron tensor analyzing powers T(20) and T(21) at the MIT-Bates Linear Accelerator Center. Data were collected simultaneously over a momentum transfer range Q=2.15-4.50 fm(-1) with the Bates Large Acceptance Spectrometer Toroid using a highly polarized deuterium internal gas target. The data are in excellent agreement with calculations in a framework of effective field theory. The deuteron charge monopole and quadrupole form factors G(C) and G(Q) were separated with improved precision, and the location of the first node of G(C) was confirmed at Q=4.19±0.05 fm(-1). The new data provide a strong constraint on theoretical models in a momentum transfer range covering the minimum of T(20) and the first node of G(C).

3.
Am J Psychiatry ; 156(3): 393-9, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10080554

RESUMO

OBJECTIVE: The authors tested a model of hallucinated "voices" based on a neural network computer simulation of disordered speech perception. METHOD: Twenty-four patients with schizophrenia spectrum disorders who reported hallucinated voices were compared with 21 patients with schizophrenia spectrum disorders who did not report voices and 26 normal subjects. Narrative speech perception was assessed through use of a masked speech tracking task with three levels of superimposed phonetic noise. A sentence repetition task was used to assess grammar-dependent verbal working memory, and an auditory continuous performance task was used to assess nonlanguage attention. RESULTS: Masked speech tracking task and sentence repetition performance by hallucinating patients was impaired relative to both nonhallucinating patients and normal subjects. Although both hallucinating and nonhallucinating patients demonstrated auditory attention impairments when compared to normal subjects, the two patient groups did not differ with respect to these variables. CONCLUSIONS: Results support the hypothesis that hallucinated voices in schizophrenia arise from disrupted speech perception and verbal working memory systems rather than from nonlanguage cognitive or attentional deficits.


Assuntos
Alucinações/diagnóstico , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Percepção da Fala , Adulto , Atenção/fisiologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/psicologia , Feminino , Alucinações/psicologia , Humanos , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Modelos Neurológicos , Redes Neurais de Computação , Esquizofrenia/fisiopatologia , Percepção da Fala/fisiologia , Comportamento Verbal/fisiologia
4.
Phys Rev Lett ; 85(21): 4446-9, 2000 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11082567

RESUMO

We report a 0 degrees 176Yb(p,n)176Lu measurement at IUCF where we used 120 and 160 MeV protons and the energy dependence method to determine Gamow-Teller (GT) matrix elements relative to the model independent Fermi matrix element. The data show that there is an isolated concentration of GT strength in the low-lying 1(+) states making the proposed Low Energy Neutrino Spectroscopy detector (based on neutrino captures on 176Yb) sensitive to pp and 7Be neutrinos and a promising detector to resolve the solar neutrino problem.

5.
Cancer Genet Cytogenet ; 98(1): 43-9, 1997 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-9309117

RESUMO

We previously reported 9 unilateral, sporadic retinoblastomas with hypermethylation in the 5' region of the RB gene, and we found that CpG methylation in the RB promoter inhibits the binding of the retinoblastoma binding factor 1 (RBF-1) and the activating transcription factor (ATF)-like factors, thereby resulting in a considerable reduction in RB promoter activity. In this study, we screened for hypermethylation in 121 additional cases of retinoblastoma, and found 5 tumors with hypermethylation, including 4 unilateral, sporadic tumors, and one hereditary tumor. The hereditary tumor had a germline deletion of one allele, and the hypermethylation was an acquired, epigenetic change in the other allele. Another tumor had hypermethylation restricted to approximately 800 base pairs in the RB promoter region including the essential RBF-1 and ATF sites. The frequency of hypermethylation in unilateral, sporadic tumors was 9.3% combining our previous and present examinations (13 among 140), whereas the frequency was 1.0% in bilateral hereditary tumors (one among 101). The statistical analyses using the chi-square test indicated significant correlation between hypermethylation and unilateral, sporadic tumors (p < 0.05). These results suggest that hypermethylation in the RB gene is always an acquired, epigenetic change and causes about 9% of unilateral, sporadic tumors.


Assuntos
Metilação de DNA , Genes do Retinoblastoma , Retinoblastoma/genética , Southern Blotting , Humanos , Regiões Promotoras Genéticas
6.
Arch Dermatol ; 111(1): 73-5, 1975 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-47238

RESUMO

In a case of giant keratoacanthoma of the nose, the lesion was extremely invasive, destroying the entire nose. Electrosurgical removal of the grossly abnormal tissue was followed by rapid recurrence on two occasions. Radiation therapy was not effective. The lesion healed after the use of bleomycin sulfate.


Assuntos
Ceratoacantoma/patologia , Neoplasias Nasais/patologia , Adulto , Bleomicina/uso terapêutico , Humanos , Ceratoacantoma/tratamento farmacológico , Ceratoacantoma/cirurgia , Masculino , Recidiva Local de Neoplasia , Neoplasias Nasais/tratamento farmacológico , Neoplasias Nasais/cirurgia
7.
Am J Ophthalmol ; 97(6): 681-5, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6731533

RESUMO

Determinations of esterase D isoenzymes in the members of a family with hereditary retinoblastoma gave results consistent with linkage between the loci for esterase D and retinoblastoma. This gene linkage allows the detection of gene carrier states in certain kindreds. We used this technique to predict that a 6-month-old boy carries the tumor-predisposing retinoblastoma gene.


Assuntos
Carboxilesterase , Hidrolases de Éster Carboxílico/genética , Neoplasias Oculares/genética , Isoenzimas/genética , Retinoblastoma/genética , Adulto , Alelos , Mapeamento Cromossômico , Feminino , Triagem de Portadores Genéticos , Ligação Genética , Humanos , Lactente , Masculino , Linhagem , Recombinação Genética
8.
Phys Med Biol ; 33(3): 315-28, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3362970

RESUMO

Recent measurements of differential elastic and inelastic neutron scattering from oxygen, nitrogen and calcium at 18 less than En less than 26 MeV are presented and analysed in terms of the optical model. These data, together with earlier measurements of scattering and total cross sections, are used to construct model potentials that may be used to calculate various quantities of interest in neutron dosimetry in an energy region (20-60 MeV) where very few cross section data are available. The heavy-ion-recoil contribution to kerma is obtained directly from the data at each energy. The value of proton inelastic scattering data for validating potential models at high energy is discussed.


Assuntos
Cálcio , Nêutrons Rápidos , Nêutrons , Nitrogênio , Oxigênio
9.
Phys Rev Lett ; 69(16): 2444, 1992 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-10046487
20.
Harefuah ; 108(3-4): 84-91, 1985 Aug.
Artigo em Hebraico | MEDLINE | ID: mdl-4076883
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