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1.
Phys Rev Lett ; 129(20): 201801, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36461983

RESUMEN

This Letter presents the results from the MiniBooNE experiment within a full "3+1" scenario where one sterile neutrino is introduced to the three-active-neutrino picture. In addition to electron-neutrino appearance at short baselines, this scenario also allows for disappearance of the muon-neutrino and electron-neutrino fluxes in the Booster Neutrino Beam, which is shared by the MicroBooNE experiment. We present the 3+1 fit to the MiniBooNE electron-(anti)neutrino and muon-(anti)neutrino data alone and in combination with MicroBooNE electron-neutrino data. The best-fit parameters of the combined fit with the exclusive charged-current quasielastic analysis (inclusive analysis) are Δm^{2}=0.209 eV^{2}(0.033 eV^{2}), |U_{e4}|^{2}=0.016(0.500), |U_{µ4}|^{2}=0.500(0.500), and sin^{2}(2θ_{µe})=0.0316(1.0). Comparing the no-oscillation scenario to the 3+1 model, the data prefer the 3+1 model with a Δχ^{2}/d.o.f.=24.7/3(17.3/3), a 4.3σ(3.4σ) preference assuming the asymptotic approximation given by Wilks's theorem.

2.
Phys Rev Lett ; 129(2): 021801, 2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35867467

RESUMEN

We report the first results of a search for leptophobic dark matter (DM) from the Coherent-CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) and 17.9×10^{20} protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005+16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of m_{V_{B}}/m_{χ}=2.1, DM masses within the range 9 MeV≲m_{χ}≲50 MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM's upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.

3.
Phys Rev Lett ; 123(4): 042502, 2019 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-31491269

RESUMEN

We report the first measurement of the neutron cross section on argon in the energy range of 100-800 MeV. The measurement was obtained with a 4.3-h exposure of the Mini-CAPTAIN detector to the WNR/LANSCE beam at LANL. The total cross section is measured from the attenuation coefficient of the neutron flux as it traverses the liquid argon volume. A set of 2631 candidate interactions is divided in bins of the neutron kinetic energy calculated from time-of-flight measurements. These interactions are reconstructed with custom-made algorithms specifically designed for the data in a time projection chamber the size of the Mini-CAPTAIN detector. The energy averaged cross section is 0.91±0.10(stat)±0.09(syst) b. A comparison of the measured cross section is made to the GEANT4 and FLUKA event generator packages, where the energy averaged cross sections in this range are 0.60 and 0.68 b, respectively.

4.
Int J Tuberc Lung Dis ; 15(7): 943-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21682969

RESUMEN

SETTING: A passive case-finding strategy as present in the DOTS strategy presupposes a patient's willingness to seek care. This requires awareness of tuberculosis (TB) symptoms and the diagnostic process, and positive attitudes towards access and probability of cure. OBJECTIVE: To measure parameters of health-seeking intention in Southern Angola and to inform the design of context-specific interventions to improve case detection. DESIGN: A survey in four communities based on the cough-to-cure pathway represented by five domains with either one or two proxy measures. These were assessed for association with appropriate health-seeking behaviour (visiting a medical institution or service). RESULTS: In total, 805 individuals were included in the study. Appropriate health-seeking behaviour was positively associated with knowing the disease (OR 3.1, 95%CI 1.4-6.8), knowing key symptoms (OR 1.4, 95%CI 1.0-1.9), perceived curability (OR 1.3, 95%CI 1.0-1.6), and the perception that TB services were free of charge (OR 1.9, 95%CI 1.4-2.7). Respondents who perceived a personal risk for TB were less likely to have an appropriate intended health-seeking behaviour (OR 0.7, 95%CI 0.5-0.9). CONCLUSION: Knowledge about TB should include key symptoms, perceived curability and information on access to services when designing interventions to improve case detection. The study highlights the importance of advocacy, social mobilisation and communication strategies.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Aceptación de la Atención de Salud/estadística & datos numéricos , Tuberculosis/psicología , Adulto , Angola , Actitud Frente a la Salud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Tuberculosis/diagnóstico , Tuberculosis/terapia
5.
Diabetes Obes Metab ; 5(6): 438-45, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14617230

RESUMEN

BACKGROUND: The glycaemic control of thrice daily treatment with premixed biphasic insulin aspart (BIAsp) without other antidiabetic therapy was tested in type 2 diabetic patients, in order to compare the glucose control of a 'high' mixture (BIAsp 70) or a 'medium' mixture (BIAsp 50) (70 or 50% soluble IAsp and 30 or 50% protamine-crystallized IAsp, respectively) administered just before dinner. AIM: To compare these regimens to conventional 30 : 70 premixture on a twice a day basis. METHODS: This randomized, double-blind, two-period crossover study included 16 patients with type 2 diabetes. Twenty four-hour serum glucose and insulin profiles were obtained thrice: (1) after a one-week run-in period with biphasic human insulin (BHI) 30/70 twice daily (run-in), (2) after 4 weeks of treatment with thrice daily BIAsp 70 before breakfast, lunch and dinner (Dinner70 regimen) and (3) after 4 weeks of BIAsp 70 before breakfast and lunch and BIAsp 50 before dinner (Dinner50). RESULTS: Daytime average serum glucose was lower with Dinner70 compared to run-in (9.6 +/- 0.39 mmol/l vs. 11.2 +/- 0.61 mmol/l, p < 0.05). Postprandial glucose excursions after breakfast and lunch were lower, but fasting morning glucose was higher during the treatment periods than in the run-in period. Twenty four-hour C-peptide AUC was considerably lower during both treatment periods than in the run-in period (run-in/Dinner50 ratio 1.29 [1.08; 1.54] p < 0.01; run-in/Dinner70 ratio 1.31 [1.08;1.58], p < 0.01). CONCLUSIONS: Switching the dinner dose to BIAsp 50 did not alter overall glucose control significantly from that provided with BIAsp 70. Exploratory analyses between the two active treatment regimens and run-in/BHI indicate that thrice daily BIAsp 70 administration: (1) for optimization of the night-time control, the dinner dose needs adjustment or replacement by a premixed insulin with a larger proportion of basal insulin than BIAsp 50 and (2) none of the premixtures adequately provide for both the evening meal and overnight requirements.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Insulina/análogos & derivados , Insulina/administración & dosificación , Anciano , Glucemia/efectos de los fármacos , Péptido C/sangre , Ritmo Circadiano , Estudios Cruzados , Diabetes Mellitus Tipo 2/sangre , Método Doble Ciego , Esquema de Medicación , Ayuno/sangre , Femenino , Humanos , Hipoglucemiantes/sangre , Insulina/sangre , Insulina Aspart , Masculino , Persona de Mediana Edad , Periodo Posprandial/fisiología
6.
Diabet Med ; 19(5): 393-9, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12027927

RESUMEN

AIM: To compare the efficacy and safety of premixed insulin aspart (30% free and 70% protamine-bound, BIAsp 30) with human insulin premix (BHI 30) used in a twice-daily injection regimen in people with Type 1 and Type 2 diabetes. METHODS: People with Type 1 and Type 2 diabetes (n = 294) using twice-daily insulin were randomized to a 12-week open-label comparison of BIAsp 30 and BHI 30. Efficacy was assessed by analysis of variance of 12-week data, adjusted for baseline level. RESULTS: BIAsp 30 was as effective as BHI 30 based on the primary efficacy measure, HbA1c, mean difference -0.01 (90% confidence interval (CI) -0.14; 0.12) %Hb. Meal-time self-measured blood glucose increment averaged over the three main meals was significantly lower in the BIAsp 30 group than in the BHI 30 group (-0.68 (-1.20; -0.16) mmol/l; P < 0.02). Significant improvements were observed after breakfast, before lunch, after dinner and at bedtime (P < 0.02-0.05), with blood glucose around 1.0 mmol/l lower in the BIAsp 30 group. The number of major hypoglycaemic episodes with BIAsp 30 was half that with BHI 30. However, the overall risk of both minor and major hypoglycaemia did not differ significantly between treatments. CONCLUSION: Post-prandial glycaemic control was significantly improved, without increasing the risk of hypoglycaemia, and overall control was similar when people with Type 1 and Type 2 diabetes were treated on a twice-daily regimen with immediate premeal injections of BIAsp 30 compared with BHI 30.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Adulto , Insulinas Bifásicas , Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 2/sangre , Esquema de Medicación , Combinación de Medicamentos , Femenino , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Hipoglucemiantes/efectos adversos , Insulina/efectos adversos , Insulina/análogos & derivados , Insulina Aspart , Insulina Isófana , Masculino , Persona de Mediana Edad
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