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1.
BMJ Mil Health ; 169(3): 197-204, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33664088

RESUMO

BACKGROUND: Electronic cigarette (or e-cigarette) use has grown substantially since its US market introduction in 2007. Although marketed as a safer alternative to traditional cigarettes, studies have shown they can also be a gateway to their use. The purpose of this investigation is to identify factors associated with different patterns of tobacco use among active duty military personnel. METHODS: A secondary analysis was conducted using the 2014 Defense Health Agency Health Related Behaviors survey data. Results are based on 45 986 US military respondents, weighted to 1 251 606. Both univariate and regression analyses were conducted to identify correlates. RESULTS: In 2014, approximately 7.8% of respondents reported using e-cigarettes at least once in the past year. Among e-cigarette users, 49% reported exclusive e-cigarette use. Prevalence of exclusive use is highest among white people (58%), Navy (33%), men (83%) and persons with income ≤$45 000 (65%). Regression comparing exclusive cigarette with exclusive e-cigarette users revealed higher odds of being Air Force (OR=2.19; CI 1.18 to 4.06) or Navy (OR=2.25; CI 1.14 to 4.41) personnel and being male (OR=1.72; CI 1.12 to 2.64), and more likely to not receive smoking cessation messaging from healthcare providers in the last 12 months (OR=2.88; CI 1.80 to 4.62). When comparing exclusive e-cigarette users with poly-tobacco users, e-cigarette users had higher odds of being Hispanic (OR=2.20; CI 1.02 to 4.78), college educated (OR=4.25; CI 1.22 to 14.84) and not receiving tobacco prevention/cessation messaging (OR=4.80; CI 2.79 to 8.27). CONCLUSION: The results demonstrate that exclusive e-cigarette users in the military have unique characteristics when compared with groups of other/mixed tobacco users. Findings can inform cessation and prevention efforts to improve both the overall health and combat readiness of active duty military personnel.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Militares , Produtos do Tabaco , Vaping , Humanos , Masculino , Feminino , Vaping/epidemiologia , Comportamentos Relacionados com a Saúde
2.
Phys Rev Lett ; 129(23): 232502, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36563213

RESUMO

Neutrinoless double beta decay (0νßß) processes sample a wide range of intermediate forbidden nuclear transitions, which may be impacted by quenching of the axial vector coupling constant (g_{A}/g_{V}), the uncertainty of which plays a pivotal role in determining the sensitivity reach of 0νßß experiments. In this Letter, we present measurements performed on a high-resolution LiInSe_{2} bolometer in a "source=detector" configuration to measure the spectral shape of the fourfold forbidden ß decay of ^{115}In. The value of g_{A}/g_{V} is determined by comparing the spectral shape of theoretical predictions to the experimental ß spectrum taking into account various simulated background components as well as a variety of detector effects. We find evidence of quenching of g_{A}/g_{V} at >5σ with a model-dependent quenching factor of 0.655±0.002 as compared to the free-nucleon value for the interacting shell model. We also measured the ^{115}In half-life to be [5.18±0.06(stat)_{-0.015}^{+0.005}(sys)]×10^{14} yr within the interacting shell model framework. This Letter demonstrates the power of the bolometeric technique to perform precision nuclear physics single-ß decay measurements, which along with improved nuclear modeling can help reduce the uncertainties in the calculation of several decay nuclear matrix elements including those used in 0νßß sensitivity calculations.

3.
Phys Rev Lett ; 122(19): 192501, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144924

RESUMO

We present a precision analysis of the ^{136}Xe two-neutrino ßß electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ßß rate allows us to measure the ratio of the leading and subleading 2νßß nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ßß decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ßß NMEs.

5.
Phys Rev Lett ; 117(8): 082503, 2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27588852

RESUMO

We present an improved search for neutrinoless double-beta (0νßß) decay of ^{136}Xe in the KamLAND-Zen experiment. Owing to purification of the xenon-loaded liquid scintillator, we achieved a significant reduction of the ^{110m}Ag contaminant identified in previous searches. Combining the results from the first and second phase, we obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>1.07×10^{26} yr at 90% C.L., an almost sixfold improvement over previous limits. Using commonly adopted nuclear matrix element calculations, the corresponding upper limits on the effective Majorana neutrino mass are in the range 61-165 meV. For the most optimistic nuclear matrix elements, this limit reaches the bottom of the quasidegenerate neutrino mass region.

7.
J Instrum ; 8(10)2013 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25392711

RESUMO

Semiconductor nanoparticles (quantum dots) were studied in the context of liquid scintillator development for upcoming neutrino experiments. The unique optical and chemical properties of quantum dots are particularly promising for the use in neutrinoless double-beta decay experiments. Liquid scintillators for large scale neutrino detectors have to meet specific requirements which are reviewed, highlighting the peculiarities of quantum-dot-doping. In this paper, we report results on laboratory-scale measurements of the attenuation length and the fluorescence properties of three commercial quantum dot samples. The results include absorbance and emission stability measurements, improvement in transparency due to filtering of the quantum dot samples, precipitation tests to isolate the quantum dots from solution and energy transfer studies with quantum dots and the fluorophore PPO.

8.
Phys Rev Lett ; 109(14): 141802, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-23083237

RESUMO

This paper introduces an experimental probe of the sterile neutrino with a novel, high-intensity source of electron antineutrinos from the production and subsequent decay of 8Li. When paired with an existing ∼1 kton scintillator-based detector, this = 6.4 MeV source opens a wide range of possible searches for beyond standard model physics via studies of the inverse beta decay interaction ν(e) + p → e+ + n. In particular, the experimental design described here has unprecedented sensitivity to ν(e) disappearance at Δm2 ∼ 1 eV2 and features the ability to distinguish between the existence of zero, one, and two sterile neutrinos.

11.
J Exp Biol ; 204(Pt 1): 147-56, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11104718

RESUMO

We report the identification of an invertebrate Na(+)/K(+)/2Cl(-) cotransporter, NKCC. As a model system, we used the immune cells (coelomocytes) of the Mediterranean sea urchin Paracentrotus lividus. These cells are particularly interesting because they can be activated to undergo a rapid and dynamic change in cell shape. We demonstrate that forskolin, a cyclic AMP agonist known to regulate NKCC, induced coelomocyte transformation at doses of 10 micromol l(-)(1) and greater. Using two distinct monoclonal antibodies (T4 and T9) raised against the human intestinal epithelial NKCC, we have identified a high-molecular-mass (195 kDa) protein in coelomocyte extracts. We propose a novel method for the isolation of NKCC in one step by using bumetanide-Sepharose affinity chromatography under low-[Cl(-)] conditions. This method was successful in isolating coelomocyte 195 kDa NKCC. The T4 monoclonal antibody was used in immunocytochemical experiments to localize NKCC in resting and activated coelomocytes. In petalloid coelomocytes, a punctate, cytoplasmic distribution was observed in close proximity to actin filament bundles; in transformed coelomocytes, the immunofluorescence was distributed along the length of the filopodia and uniformly throughout the perinuclear region. The change in subcellular distribution of NKCC between the resting and the activated state was further investigated by using cell surface biotinylation followed by immunoprecipitation. These studies revealed an upregulation of NKCC at the plasma membrane upon activation, a process that was blocked by the F-actin-stabilizing drug phalloidin. These studies identify a novel model system in which to investigate a newly identified invertebrate Na(+)/K(+)/2Cl(-) cotransporter.


Assuntos
Citoesqueleto de Actina/química , Proteínas de Transporte/análise , AMP Cíclico/farmacologia , Soluções Hipotônicas , Ouriços-do-Mar , Frações Subcelulares/química , Actinas , Animais , Tamanho Celular , Colforsina/farmacologia , AMP Cíclico/metabolismo , Citoesqueleto/química , Ouriços-do-Mar/citologia , Simportadores de Cloreto de Sódio-Potássio
12.
Anaesth Intensive Care ; 27(5): 477-80, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10520387

RESUMO

The marked vasodilator and negative inotropic effects of propofol are disadvantages in frail elderly patients. We investigated the safety and efficacy of adding different doses of ephedrine to propofol in order to obtund the hypotensive response. The haemodynamic effects of adding 15, 20 or 25 mg of ephedrine to 200 mg of propofol were compared to control in 40 ASA 3/4 patients over 60 years presenting for genito-urinary surgery. The addition of ephedrine to propofol appears to be an effective method of obtunding the hypotensive response to propofol at all doses used in this study. However, marked tachycardia associated with the use of ephedrine in combination with propofol occurred in the majority of patients, occasionally reaching high levels in individual patients. Due to the risk of this tachycardia inducing myocardial ischemia, we would not recommend the use in elderly patients of any of the ephedrine/propofol/mixtures studied.


Assuntos
Adrenérgicos/farmacologia , Efedrina/farmacologia , Hemodinâmica/efeitos dos fármacos , Propofol/farmacologia , Idoso , Anestésicos Intravenosos/administração & dosagem , Anestésicos Intravenosos/efeitos adversos , Anestésicos Intravenosos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Efedrina/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipotensão/induzido quimicamente , Hipotensão/prevenção & controle , Propofol/administração & dosagem , Propofol/efeitos adversos
13.
Arch Intern Med ; 158(20): 2192-9, 1998 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-9818799

RESUMO

Herbs and related products are commonly used by patients who also seek conventional health care. All physicians, regardless of specialty or interest, care for patients who use products that are neither prescribed nor recommended. Some herbs have been extensively studied, but little is known about others. When a patient asks for advice regarding the use of a particular herb, how should a physician respond? Similarly, how does a physician determine if a patient's symptoms are caused by a "remedy"? This review attempts to answer these questions by investigating pertinent definitions, the history of herbs in medicine, epidemiology and prevalence of herbal use, and relevant psychosocial issues.


Assuntos
Magnoliopsida/uso terapêutico , Fitoterapia , Custos de Medicamentos , Humanos , Magnoliopsida/efeitos adversos , Magnoliopsida/economia , Magnoliopsida/normas , Estados Unidos
14.
Cleve Clin J Med ; 65(7): 388-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9679395
15.
Anaesthesia ; 51(5): 488-91, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8694167

RESUMO

Forty ASA1 patients presenting for minor gynaecological surgery were randomly allocated into four study groups to compare the haemodynamic effects of adding different doses of ephedrine to an induction dose of propofol. Heart rate, oxygen saturation and non-invasive arterial blood pressure were monitored before and for 5 min after induction. In those patients who received propofol alone, there was a significant decrease in both systolic (p < 0.001) and diastolic (p = 0.003) blood pressure. The addition of ephedrine 15 mg or 20 mg to 1% propofol 20 ml was very effective in maintaining blood pressure at pre-induction values. There was a statistically significant increase from baseline in systolic (p = 0.004) and diastolic (p = 0.031) pressures, but this only occurred at 1 min postinduction. The addition of ephedrine 10 mg was insufficient to prevent hypotension. There was no significant effect on either heart rate or oxygen saturation in any group. We conclude that ephedrine may be safely employed to reduce the degree of hypotension during induction with propofol in this patient group.


Assuntos
Anestésicos Intravenosos/efeitos adversos , Efedrina/uso terapêutico , Hipotensão/prevenção & controle , Propofol/efeitos adversos , Vasoconstritores/uso terapêutico , Adulto , Anestésicos Intravenosos/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Efedrina/administração & dosagem , Feminino , Genitália Feminina/cirurgia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipotensão/induzido quimicamente , Oxigênio/sangue , Propofol/administração & dosagem , Vasoconstritores/administração & dosagem
16.
J Gerontol ; 43(3): P63-70, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3361091

RESUMO

A pair of surveys asked healthy adults about their everyday visual problems. Participants ranged in age from 18 to 100 and were screened for major visual impairment. Respondents rated the frequency of difficulty they had performing visual tasks such as reading, recognizing objects, picking out a face in a crowd, seeing in dimly lit environments, seeing moving objects, and so on. The surveys revealed five dimensions that declined with increasing age: visual processing speed, light sensitivity, dynamic vision, near vision, and visual search. The percentage of respondents reporting a decline in these visual dimensions increased two- to sixfold across the adult life span. Varying rates of visual decline for different tasks suggest that various aspects of vision age at different rates.


Assuntos
Envelhecimento/fisiologia , Transtornos da Visão/fisiopatologia , Visão Ocular/fisiologia , Atividades Cotidianas , Adaptação Ocular , Adolescente , Adulto , Idoso , Oftalmopatias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Parasitology ; 82(Pt 3): 383-7, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7243347

RESUMO

Antibodies to Toxocara were measured by enzyme-linked immunosorbent assay (ELISA) in sera of ascarid-free dogs which had been fed 0, 100 or 10 000 embryonated T. canis eggs. Dogs fed 10 000 eggs developed higher titres than those given 100 eggs and larvae failed to complete their migration to the gut. In addition, in dogs given 100 eggs, there was a significant negative correlation between the number of worms in the gut and granulomatous foci in the lung. The data suggest that the ELISA is sensitive and specific for Toxocara infection in dogs.


Assuntos
Anticorpos/análise , Ascaríase/veterinária , Doenças do Cão/imunologia , Toxocara/imunologia , Toxocaríase/veterinária , Animais , Cães , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Intestinos/parasitologia , Pulmão/parasitologia , Toxocara/isolamento & purificação , Toxocaríase/imunologia
18.
Am J Trop Med Hyg ; 30(1): 77-80, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7212174

RESUMO

Blood samples were obtained during a lead screening program from 100 children aged 1-6 years in Allegheny County, Pennsylvania, to determine whether there was any association between specific forms of pica and infection with Toxocara canis, the principal cause of visceral larva migrans in the United States, or elevated blood lead levels. Significant associations were found between: 1) feces, soil, or grass pica and Toxocara infection; 2) paint or plaster pica and elevated blood lead; and 3) dog ownership and Toxocara infection. These findings suggest that an accurate pica history may be useful in identifying potential health problems in children.


Assuntos
Larva Migrans Visceral/etiologia , Chumbo/sangue , Pica/complicações , Animais , Criança , Pré-Escolar , Cães , Fezes/parasitologia , Feminino , Humanos , Lactente , Larva Migrans Visceral/transmissão , Masculino , Pica/sangue , Pica/parasitologia , Toxocara/isolamento & purificação
19.
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