Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Eur Phys J C Part Fields ; 83(9): 782, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37680254

RESUMEN

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7(16.3)×1020 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7×1020 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin2θ13 and the impact of priors on the δCP measurement. Both analyses prefer the normal mass ordering and upper octant of sin2θ23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin2θ13 from reactors, sin2θ23=0.561-0.032+0.021 using Feldman-Cousins corrected intervals, and Δm322=2.494-0.058+0.041×10-3eV2 using constant Δχ2 intervals. The CP-violating phase is constrained to δCP=-1.97-0.70+0.97 using Feldman-Cousins corrected intervals, and δCP=0,π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2σ credible level using a flat prior in δCP, and just below 2σ using a flat prior in sinδCP. When the external constraint on sin2θ13 is removed, sin2θ13=28.0-6.5+2.8×10-3, in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

2.
Phys Rev Lett ; 124(16): 161802, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-32383902

RESUMEN

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

3.
Phys Rev Lett ; 121(17): 171802, 2018 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-30411920

RESUMEN

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3} eV^{2}/c^{4}.

4.
Phys Rev Lett ; 118(15): 151801, 2017 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-28452532

RESUMEN

T2K reports its first results in the search for CP violation in neutrino oscillations using appearance and disappearance channels for neutrino- and antineutrino-mode beams. The data include all runs from January 2010 to May 2016 and comprise 7.482×10^{20} protons on target in neutrino mode, which yielded in the far detector 32 e-like and 135 µ-like events, and 7.471×10^{20} protons on target in antineutrino mode, which yielded 4 e-like and 66 µ-like events. Reactor measurements of sin^{2}2θ_{13} have been used as an additional constraint. The one-dimensional confidence interval at 90% for the phase δ_{CP} spans the range (-3.13, -0.39) for normal mass ordering. The CP conservation hypothesis (δ_{CP}=0, π) is excluded at 90% C.L.

5.
Phys Rev Lett ; 117(19): 192501, 2016 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-27858422

RESUMEN

We report the first measurement of the flux-averaged cross section for charged current coherent π^{+} production on carbon for neutrino energies less than 1.5 GeV, and with a restriction on the final state phase space volume in the T2K near detector, ND280. Comparisons are made with predictions from the Rein-Sehgal coherent production model and the model by Alvarez-Ruso et al., the latter representing the first implementation of an instance of the new class of microscopic coherent models in a neutrino interaction Monte Carlo event generator. We observe a clear event excess above background, disagreeing with the null results reported by K2K and SciBooNE in a similar neutrino energy region. The measured flux-averaged cross sections are below those predicted by both the Rein-Sehgal and Alvarez-Ruso et al.

6.
Phys Rev Lett ; 116(18): 181801, 2016 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-27203315

RESUMEN

T2K reports its first measurements of the parameters governing the disappearance of ν[over ¯]_{µ} in an off-axis beam due to flavor change induced by neutrino oscillations. The quasimonochromatic ν[over ¯]_{µ} beam, produced with a peak energy of 0.6 GeV at J-PARC, is observed at the far detector Super-Kamiokande, 295 km away, where the ν[over ¯]_{µ} survival probability is expected to be minimal. Using a data set corresponding to 4.01×10^{20} protons on target, 34 fully contained µ-like events were observed. The best-fit oscillation parameters are sin^{2}(θ[over ¯]_{23})=0.45 and |Δm[over ¯]_{32}^{2}|=2.51×10^{-3} eV^{2} with 68% confidence intervals of 0.38-0.64 and 2.26-2.80×10^{-3} eV^{2}, respectively. These results are in agreement with existing antineutrino parameter measurements and also with the ν_{µ} disappearance parameters measured by T2K.

7.
J Affect Disord ; 196: 20-31, 2016 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-26897454

RESUMEN

BACKGROUND: Research evidence on the effects of integrated multifaceted lifestyle interventions for depression is scanty. The aim of the present study is to report on the development, acceptability and efficacy of a standardized healthy lifestyle intervention, including exercise, eating habits, sleep hygiene and smoking cessation in preventing relapses. METHODS: One hundred-sixty outpatients with recurrent unipolar depression or bipolar disorder were recruited after achieving full remission or recovery from the most recent depressive episode. Patients were randomized to 3-months of usual care or to an intervention aimed at promoting a healthy lifestyle (HLI), as an augmentation of pharmacological maintenance treatment. Usual care consisted of clinical management visits. At the end of the intervention, follow-up visits were scheduled at 3,6,9 and 12 months. RESULTS: During the intervention phase, 1 relapse occurred in the HLI group and 4 in the control group. Over the 12 months of follow-up, relapses were 5 in the HLI group and 16 in control group. Using an intent-to-treat approach, the overall percentage of relapses was 6/81 (7.4%) in the HLI group vs. 20/79 (25.3%) in the control group.. In a Kaplan-Meier survival analysis the risk of relapse was significantly lower in patients receiving the HLI intervention (log-rank test, p=0.003) over the 60 weeks of observation. The majority of patients assigned to HLI adhered to the program, and were highly motivated throughout the intervention. LIMITATIONS: The retention rate was low because patients were recruited during the maintenance phase and the 1-year follow-up was relatively short to detect a long-term effect of HLI. CONCLUSIONS: The HLI program proved to be efficacious in preventing relapses. Given the absence of contraindications and its cost-effectiveness in routine practice, the use of HLI should be encouraged to promote the well-being of patients with recurrent depression.


Asunto(s)
Trastorno Bipolar/prevención & control , Trastorno Depresivo Mayor/prevención & control , Estilo de Vida , Prevención Secundaria/métodos , Adulto , Antidepresivos/uso terapéutico , Trastorno Bipolar/psicología , Terapia Combinada , Análisis Costo-Beneficio , Trastorno Depresivo Mayor/psicología , Femenino , Estudios de Seguimiento , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Motivación , Pacientes Ambulatorios , Recurrencia , Cese del Hábito de Fumar
8.
Recenti Prog Med ; 90(9): 470-2, 1999 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-10544668

RESUMEN

The aplastic anemia methimazole induced is a rare event. We describe a case of a woman, affected by hyperthyroidism, who suffers from bone marrow aplasia during Tapazole treatment, and literature has been reviewed. Stopping methimazole and beginning a therapy with methylprednisolone in high dosage, intravenous IgG in high dosage, filgastrin and danatrol, medullary recover after 11 days of treatment is obtained. By analyzing our case and the 12 further cases described, we find that the prognosis of aplastic anemia during the treatment of antithyroid therapy, is rather good. Even if the pathogenetic mechanism of Tapazole induced bone marrow aplasia, it seems to be immuno-mediated in most cases, a direct toxicity in bone marrow cannot be excluded. In examined cases the antithyroid dosage was medium high (mean 40 mg/die). Therefore the use of Tapazole in low doses (15 mg/die) effective in almost all hyperthyroid patient must be considered, when possible, the best therapeutic choice, since it is safer in the incidence of important side effects such as bone marrow aplasia, especially in elderly patients or in patients with chronic renal failure.


Asunto(s)
Anemia Aplásica/inducido químicamente , Antitiroideos/efectos adversos , Metimazol/efectos adversos , Adulto , Anciano , Anemia Aplásica/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Danazol/uso terapéutico , Antagonistas de Estrógenos/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Hipertiroidismo/tratamiento farmacológico , Inmunoglobulinas Intravenosas/uso terapéutico , Masculino , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Factores de Tiempo
9.
Recenti Prog Med ; 85(2): 96-100, 1994 Feb.
Artículo en Italiano | MEDLINE | ID: mdl-8184195

RESUMEN

A clinical trial was performed to evaluate efficacy and tolerability of Bay-o-9867 in the treatment of UTI and LRTI. 40 patients were admitted to the study: 27 affected with LRTI, mainly exacerbations of COPD, and 15 affected with UTI. Two patients were affected concomitantly with a UTI and LRTI. The patients were treated with Bay-o-9867 (ciprofloxacin) administered orally at a daily dosage of 500 mg (250 q 12 h) in 30 patients and of 1000 mg (500 q 12 h) in 10 patients, depending on the severity of infection. Clinical results were extremely favourable as complete clinical resolution of infective episode was achieved in 38 patients (15/15 in UTI patients; 25/27 in LRTI patients), whereas improvement was achieved in 2 (in LRTI). Overall clinical efficacy was therefore successful in 100% of cases. Concerning bacteriological results, 38 pathogens were isolated from infective sites before starting treatment, and all were eradicated (eradication rate: 100%). Tolerability was assessed as good: no adverse event was observed.


Asunto(s)
Infecciones Bacterianas/tratamiento farmacológico , Ciprofloxacina/uso terapéutico , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones Urinarias/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Tolerancia a Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión
10.
Toxicol Lett ; 16(1-2): 69-75, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6836616

RESUMEN

Seventeen chemicals (solvents, insecticides and intermediates in the production of textiles and resins) were tested in a short-term in vitro system with human lymphocytes to determine their toxic action. The parameters studied were the tritiated thymidine uptake and cell viability in cultures grown with or without a rat liver metabolizing system (S-9 mix). Data obtained showed that 1,3-dichlorobenzene, 1,2-dichlorobenzene, hexane, 1,2-diiodoethane, 1,4-dichlorobenzene, tetrachloroethylene, 2,3-dibromopropanol, chloromethyl methyl ether, 1,2- and 1,3-dibromopropane, in order, exerted the more toxic effects; ethyl acetate, cyclohexane, cyclohexanone and benzene showed lower toxic activity. The chemicals lost their toxic power in the presence of the metabolizing system with the exception of 1,2- and 1,3-dichlorobenzene which maintained in some degree their toxicity even in the presence of the S-9 mix. Only chloromethyl methyl ether elicited unscheduled DNA synthesis acting as DNA damaging agent.


Asunto(s)
Hidrocarburos Halogenados/toxicidad , Linfocitos/efectos de los fármacos , Solventes/toxicidad , Adulto , Células Cultivadas , ADN/biosíntesis , Humanos , Linfocitos/metabolismo , Timidina/metabolismo
11.
Scand J Work Environ Health ; 8(4): 290-3, 1982 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7170626

RESUMEN

The investigation has been carried out on cultures grown in the presence of 5 x 10(-1) - 5 x 10(-5) M acrylonitrile with or without a rat liver metabolizing system (S-9 mix). The results obtained showed that acrylonitrile was toxic starting from the 5 x 10(-3) M concentration, caused a significant increase in the sister chromatid exchange (SCE) frequency in comparison with the controls (p less than or equal to 0.001) when the concentration was 5 x 10(-4) M, and elicited reparative deoxyribonucleic acid (DNA) synthesis, determined by tritiated thymidine uptake, particularly when the concentration was 5 x 10(-1) M. These effects were observed in lymphocytes of different donors and after drug activation by the S-9 mix metabolizing system.


Asunto(s)
Acrilonitrilo/farmacología , Intercambio Genético/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Linfocitos/metabolismo , Nitrilos/farmacología , Intercambio de Cromátides Hermanas/efectos de los fármacos , Adulto , Células Cultivadas , ADN/biosíntesis , Humanos , Pruebas de Mutagenicidad , Medicina del Trabajo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...