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1.
Phys Rev Lett ; 130(19): 192502, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37243659

RESUMO

We present the first measurement of the α-ß-ν angular correlation in the Gamow-Teller ß^{+} decay of ^{8}B. This was accomplished using the Beta-decay Paul Trap, expanding on our previous work on the ß^{-} decay of ^{8}Li. The ^{8}B result is consistent with the V-A electroweak interaction of the standard model and, on its own, provides a limit on the exotic right-handed tensor current relative to the axial-vector current of |C_{T}/C_{A}|^{2}<0.013 at the 95.5% confidence level. This represents the first high-precision angular correlation measurements in mirror decays and was made possible through the use of an ion trap. By combining this ^{8}B result with our previous ^{8}Li results, we demonstrate a new pathway for increased precision in searches for exotic currents.

2.
Br J Oral Maxillofac Surg ; 59(3): 353-361, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33358010

RESUMO

Our aims were to determine the prevalence and association of postoperative delirium (POD) in head and neck (H&N) cancer patients undergoing free flap reconstruction at the oral and maxillofacial surgery (OMFS) unit, Queen Elizabeth University Hospital (QEUH) Glasgow, and to assess whether these determinants can be modified to optimise patient care and reduce the occurrence of POD. Delirium remains an important problem in the postoperative care of patients undergoing major H&N surgery, and early detection and management improve overall outcomes. The patient database containing details of the preoperative physical status (including alcohol misuse, chronic comorbidity, and physiological status) of 1006 patients who underwent major H&N surgery with free-flap repair at the QEUH from 2009-2019, was analysed. Factors associated with delirium were studied, identifying univariate associations as well as multivariate models to determine independent risk factors. The incidence of POD was 7.5% (75/1006; 53 male:22 female; mean (SD) age 65.41 (13.16) years). POD was strongly associated with pre-existing medical comorbidities, excess alcohol, smoking, a prolonged surgical operating time (more than 700 minutes), tracheostomy, blood transfusion, and bony free flaps. Those with POD were at an increased risk of postoperative wound and lung complications, and were more likely to require a hospital stay of more than 21 days. Presurgical assessment should identify risk factors to optimise the diagnosis and treatment of POD, and will enhance patient care by reducing further medical and surgical complications, and overall hospital stay.


Assuntos
Delírio , Retalhos de Tecido Biológico , Neoplasias Bucais , Idoso , Delírio/epidemiologia , Delírio/etiologia , Feminino , Humanos , Masculino , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/cirurgia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Escócia/epidemiologia
3.
Phys Rev Lett ; 115(18): 182501, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26565463

RESUMO

In the standard model, the weak interaction is formulated with a purely vector-axial-vector (V-A) structure. Without restriction on the chirality of the neutrino, the most general limits on tensor currents from nuclear ß decay are dominated by a single measurement of the ß-ν[over ¯] correlation in ^{6}He ß decay dating back over a half century. In the present work, the ß-ν[over ¯]-α correlation in the ß decay of ^{8}Li and subsequent α-particle breakup of the ^{8}Be^{*} daughter was measured. The results are consistent with a purely V-A interaction and in the case of couplings to right-handed neutrinos (C_{T}=-C_{T}^{'}) limits the tensor fraction to |C_{T}/C_{A}|^{2}<0.011 (95.5% C.L.). The measurement confirms the ^{6}He result using a different nuclear system and employing modern ion-trapping techniques subject to different systematic uncertainties.

4.
Phys Rev Lett ; 110(9): 092502, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23496705

RESUMO

A measurement of the α-ß-ν[over ¯] angular correlation in the Gamow-Teller decay (8)Li→(8)Be(*)+ν[over ¯]+ß, (8)Be(*)→α+α has been performed using ions confined in a linear Paul trap surrounded by silicon detectors. The energy difference spectrum of the α particles emitted along and opposite the direction of the ß particle is consistent with the standard model prediction and places a limit of 3.1% (95.5% confidence level) on any tensor contribution to the decay. From this result, the amplitude of any tensor component C(T) relative to that of the dominant axial-vector component C(A) of the electroweak interaction is limited to |C(T)/C(A)|<0.18 (95.5% confidence level). This experimental approach is facilitated by several favorable features of the (8)Li ß decay and has different systematic effects than the previous ß-ν[over ¯] correlation results for a pure Gamow-Teller transition obtained from studying (6)He ß decay.

5.
Phys Rev Lett ; 107(21): 212502, 2011 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-22181875

RESUMO

Collinear-laser spectroscopy with the bunched-beams technique was used for the study of neutron deficient Rb isotopes, out to (74)Rb (N = Z = 37) at TRIUMF. The measured hyperfine coupling constants of (76,78m)Rb were in agreement with literature values. The nuclear spin of (75)Rb was confirmed to be I = 3/2, and its hyperfine coupling constants were measured for the first time. The mean-square charge radius of (74)Rb was determined for the first time. This result has improved the isospin symmetry breaking correction term used to calculate the Ft value, with implications for tests of the unitarity of the Cabibbo-Kobayashi-Maskawa matrix.

6.
J Med Entomol ; 43(5): 833-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17017216

RESUMO

Knowledge of ecological differences between the molecular forms of Anopheles gambiae Giles (Diptera: Culicidae) might lead to understanding of their unique contribution to disease transmission, to better vector control, and to identification of the forces that have separated them. We compared female fecundity measured as egg batch size in relation to body size between the molecular forms in Mali and contrasted them with their sibling species, Anopheles arabiensis Patton. To determine whether eggs of different egg batches are of similar "quality," we compared the total protein content of first-stage larvae (L1s), collected < 2 h after hatching in deionized water. Egg batch size significantly varied between An. gambiae and An. arabiensis and between the molecular forms of An. gambiae (mean batch size was 186.3, 182.5, and 162.0 eggs in An. arabiensis and the M and the S molecular form of An. gambiae, respectively). After accommodating female body size, however, the difference in batch size was not significant. In the S molecular form, egg protein content was not correlated with egg batch size (r = -0.08, P > 0.7) nor with female body size (r = -0.18, P > 0.4), suggesting that females with more resources invest in more eggs rather than in higher quality eggs. The mean total protein in eggs of the M form (0.407 microg per L1) was 6% higher than that of the S form (0.384 microg per L1), indicating that the M form invests a greater portion of her resources into current (rather than future) reproduction. A greater investment per offspring coupled with larger egg batch size may reflect an adaptation of the M form to low productivity larval sites as independent evidence suggests.


Assuntos
Anopheles/fisiologia , Animais , Anopheles/genética , Anopheles/parasitologia , Tamanho Corporal/fisiologia , Feminino , Fertilidade/fisiologia , Óvulo/química , Óvulo/fisiologia , Plasmodium falciparum/isolamento & purificação , Proteínas/análise , Especificidade da Espécie
7.
Phys Rev Lett ; 95(10): 102501, 2005 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-16196923

RESUMO

The masses of the radioactive nuclei (46)V and its decay daughter (46)Ti have been measured with the Canadian Penning Trap on-line Penning trap mass spectrometer to a precision of 1 x 10(-8). A Q(EC) value of 7052.90(40) keV for the superallowed beta decay of (46)V is obtained from the difference of these two masses. With this precise Q value, the Ft value for this decay is determined with improved precision. An investigation of an earlier Q-value measurement for (46)V uncovers a set of 7 measurements that cannot be reconciled with modern data and affects previous evaluations of V(ud) from superallowed Fermi decays. A new evaluation, adding our new data and removing the discredited subset, yields new values for G(V) and V(ud). When combined with recent results for V(us), this yields modified constraints for the unitarity of the Cabibbo-Kobayashi-Maskawa matrix and other extensions of the standard model.

8.
Phys Rev Lett ; 92(19): 192501, 2004 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-15169397

RESUMO

Mass measurements of 68Ge, 68As, and 68Se have been obtained with the Canadian Penning Trap mass spectrometer. The results determine the mass excess of 68Se as -54 232(19) keV, the first measurement with a precision and reliability sufficient to address the light-curve and energy output of x-ray bursts as well as the abundances of the elements synthesized. Under typical conditions used for modeling x-ray bursts, 68Se is found to cause a significant delay in the rp process nucleosynthesis.

13.
J Pers Assess ; 42(4): 392-400, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16367126

RESUMO

Developed a brief, reliable, and valid measure of attitudes toward public exposure to sexual stimuli. Both advocates and opponents of public exposure to such stimuli typically cite presumed effects upon children. Consequently many of the Likert format items in the several versions of the scale deal with prescriptive and prescriptive beliefs about the exposure of children to sex related stimuli. Over a three-year period five different groups of respondents participated in the study. Both the longer and the shorter versions of the scale administered to these groups appear to have acceptable reliabilities. In an attempt to provide construct validation information, the relationships between the Acceptance of Public Sexuality Scale and several measures of traditionalism were examined. As expected, scores on the scale were inversely related to measures of traditionalism and positively related to measures of modernity Possible uses of the scale were discussed.

16.
Am J Pathol ; 85(1): 115-30, 1976 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-970435

RESUMO

Young adult, pathogen-free rats of Sherman and Fischer (F344) substrains were inoculated intranasally with 10(8) colony-forming units (GFU) of M. pulmonis and housed for 4 to 6 weeks in environments with ammonia maintained at specific concentrations from 25 to 250 ppm. All levels of NH3--whether produced naturally from soiled bedding or derived from a purified source--significantly increased the severity of the rhinitis, otitis media, tracheitis, and pneumonia (including bronchiectasis) characteristic of murine respiratory mycoplasmosis (MRM). The prevalence of pneumonia, but not that of other respiratory lesions of MRM, showed a strong tendency to increase directly with environmental NH3 concentration. In contrast, NH3 exposure of rats not infected with M. pulmonis caused anatomic lesions that were unlike those of MRM and were limited to the nasal passages. It was concluded that environmental NH3, at concentrations commonly encountered in present day cage environments for rats, plays an important role in pathogenesis of MRM.


Assuntos
Amônia/efeitos adversos , Infecções por Mycoplasma/etiologia , Infecções Respiratórias/etiologia , Amônia/isolamento & purificação , Animais , Exposição Ambiental , Mycoplasma/patogenicidade , Infecções por Mycoplasma/patologia , Ratos , Ratos Endogâmicos F344 , Infecções Respiratórias/patologia
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