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1.
Phys Rev Lett ; 117(15): 151803, 2016 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-27768323

RESUMEN

We report results of a search for oscillations involving a light sterile neutrino over distances of 1.04 and 735 km in a ν_{µ}-dominated beam with a peak energy of 3 GeV. The data, from an exposure of 10.56×10^{20} protons on target, are analyzed using a phenomenological model with one sterile neutrino. We constrain the mixing parameters θ_{24} and Δm_{41}^{2} and set limits on parameters of the four-dimensional Pontecorvo-Maki-Nakagawa-Sakata matrix, |U_{µ4}|^{2} and |U_{τ4}|^{2}, under the assumption that mixing between ν_{e} and ν_{s} is negligible (|U_{e4}|^{2}=0). No evidence for ν_{µ}→ν_{s} transitions is found and we set a world-leading limit on θ_{24} for values of Δm_{41}^{2}≲1 eV^{2}.

2.
Phys Rev Lett ; 112(19): 191801, 2014 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-24877929

RESUMEN

We report on a new analysis of neutrino oscillations in MINOS using the complete set of accelerator and atmospheric data. The analysis combines the ν(µ) disappearance and ν(e) appearance data using the three-flavor formalism. We measure |Δm(32)(2)| = [2.28-2.46] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.35-0.65 (90% C.L.) in the normal hierarchy, and |Δm(32)(2)| = [2.32-2.53] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.34-0.67 (90% C.L.) in the inverted hierarchy. The data also constrain δ(CP), the θ(23} octant degeneracy and the mass hierarchy; we disfavor 36% (11%) of this three-parameter space at 68% (90%) C.L.

3.
Phys Rev Lett ; 110(17): 171801, 2013 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-23679706

RESUMEN

We report on ν(e) and ν(e) appearance in ν(µ) and ν(µ) beams using the full MINOS data sample. The comparison of these ν(e) and ν(e) appearance data at a 735 km baseline with θ13 measurements by reactor experiments probes δ, the θ23 octant degeneracy, and the mass hierarchy. This analysis is the first use of this technique and includes the first accelerator long-baseline search for ν(µ) → ν(e). Our data disfavor 31% (5%) of the three-parameter space defined by δ, the octant of the θ23, and the mass hierarchy at the 68% (90%) C.L. We measure a value of 2sin(2)(2θ13)sin(2)(θ23) that is consistent with reactor experiments.

4.
Phys Rev Lett ; 110(25): 251801, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23829728

RESUMEN

We report measurements of oscillation parameters from ν(µ) and ν(µ) disappearance using beam and atmospheric data from MINOS. The data comprise exposures of 10.71×10(20) protons on target in the ν(µ)-dominated beam, 3.36×10(20) protons on target in the ν(µ)-enhanced beam, and 37.88 kton yr of atmospheric neutrinos. Assuming identical ν and ν oscillation parameters, we measure |Δm2| = (2.41(-0.10)(+0.09))×10(-3) eV2 and sin2(2θ) = 0.950(-0.036)(+0.035). Allowing independent ν and ν oscillations, we measure antineutrino parameters of |Δm2| = (2.50(-0.25)(+0.23))×10(-3) eV2 and sin2(2θ) = 0.97(-0.08)(+0.03), with minimal change to the neutrino parameters.

5.
Phys Rev Lett ; 108(19): 191801, 2012 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-23003026

RESUMEN

We report an improved measurement of ν(µ) disappearance over a distance of 735 km using the MINOS detectors and the Fermilab Main Injector neutrino beam in a ν(µ)-enhanced configuration. From a total exposure of 2.95×10(20) protons on target, of which 42% have not been previously analyzed, we make the most precise measurement of Δm2=[2.62(-0.28)(+0.31)(stat)±0.09(syst)]×10(-3) eV2 and constrain the ν(µ) mixing angle sin2(2θ)>0.75 (90% C.L.). These values are in agreement with Δm2 and sin2(2θ) measured for ν(µ), removing the tension reported in [P. Adamson et al. (MINOS), Phys. Rev. Lett. 107, 021801 (2011).].

6.
Phys Rev Lett ; 107(18): 181802, 2011 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-22107623

RESUMEN

We report the results of a search for ν(e) appearance in a ν(µ) beam in the MINOS long-baseline neutrino experiment. With an improved analysis and an increased exposure of 8.2 × 10(20) protons on the NuMI target at Fermilab, we find that 2 sin(2) (θ(23))sin(2)(2θ(13))<0.12(0.20) at 90% confidence level for δ = 0 and the normal (inverted) neutrino mass hierarchy, with a best-fit of 2sin(2) (θ(23))sin(2)(2θ(13)) = 0.041(-0.031)(+0.047) (0.079(-0.053) (+0.071)). The θ(13) = 0 hypothesis is disfavored by the MINOS data at the 89% confidence level.

7.
Cancer Lett ; 67(2-3): 193-7, 1992 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-1483267

RESUMEN

The irreversible ornithine decarboxylase and extrahepatic arginase inhibitors (+)-S-2-amino-5-iodoacetamidopentanoic acid (2-AIPA) and (+)-S-2-amino-6-iodoacetamidohexanoic acid (2-AIHA) were evaluated. The LD50 tests were made in rats and mice using both compounds. Rats and mice were treated with either 2-AIPA or 2-AIHA i.p. for a period of 180 days. The treated animals showed a decrease of total serum proteins and increased ALT and AST levels. CK was also modified but inversely related to dose. Protection tests were carried out using L5178Y mouse lymphosarcoma. The mean survival time for each treated group was calculated and the percentage T/C was determined. For 2-AIPA it was 170 and for 2-AIHA it was 210 at 15 mg/kg.


Asunto(s)
Aminoácidos/farmacología , Aminocaproatos , Antineoplásicos/farmacología , Arginasa/antagonistas & inhibidores , Leucemia L5178/tratamiento farmacológico , Inhibidores de la Ornitina Descarboxilasa , Aminoácidos/toxicidad , Ácido Aminocaproico/farmacología , Ácido Aminocaproico/toxicidad , Animales , Antineoplásicos/toxicidad , Ensayos de Selección de Medicamentos Antitumorales , Masculino , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias , Ratas , Ratas Wistar
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