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1.
Phys Rev Lett ; 120(22): 221301, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29906152

RESUMO

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

2.
Phys Rev Lett ; 113(24): 241803, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25541766

RESUMO

The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ∼1 GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged ν(e) charged current cross section on carbon is measured to be ⟨σ⟩(ϕ)=1.11±0.10(stat)±0.18(syst)×10⁻³8 cm²/nucleon. The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23×10⁻³8 cm²/nucleon and the GENIE prediction is 1.08×10⁻³8 cm²/nucleon. The total ν(e) charged current cross-section result is also in agreement with data from the Gargamelle experiment.

3.
Phys Rev Lett ; 112(18): 181801, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24856687

RESUMO

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter θ23. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57×10(20) protons on target, T2K has fit the energy-dependent νµ oscillation probability to determine oscillation parameters. The 68% confidence limit on sin(2)(θ23) is 0.514(-0.056)(+0.055) (0.511±0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Δm32(2)=(2.51±0.10)×10(-3) eV(2)/c(4) (inverted hierarchy: Δm13(2)=(2.48±0.10)×10(-3) eV(2)/c(4)). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

4.
Phys Rev Lett ; 112(6): 061802, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24580687

RESUMO

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm(32)(2) and a CP violating phase δ(CP). In this neutrino oscillation scenario, assuming |Δm(32)(2)|=2.4×10(-3) eV(2), sin(2)θ(23)=0.5, and Δm322>0 (Δm(32)(2)<0), a best-fit value of sin(2)2θ(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at δ(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of θ(13) from reactor experiments, some values of δ(CP) are disfavored at the 90% C.L.

5.
Phys Rev Lett ; 111(21): 211803, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313479

RESUMO

The T2K Collaboration reports a precision measurement of muon neutrino disappearance with an off-axis neutrino beam with a peak energy of 0.6 GeV. Near detector measurements are used to constrain the neutrino flux and cross section parameters. The Super-Kamiokande far detector, which is 295 km downstream of the neutrino production target, collected data corresponding to 3.01×10(20) protons on target. In the absence of neutrino oscillations, 205±17 (syst) events are expected to be detected while only 58 muon neutrino event candidates are observed. A fit to the neutrino rate and energy spectrum, assuming three neutrino flavors and normal mass hierarchy yields a best-fit mixing angle sin2(θ23)=0.514±0.082 and mass splitting |Δm(32)(2)|=2.44(-0.15)(+0.17)×10(-3) eV2/c4. Our result corresponds to the maximal oscillation disappearance probability.

6.
Phys Rev Lett ; 107(4): 041801, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21866992

RESUMO

The T2K experiment observes indications of ν(µ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Δm(23)(2)| = 2.4×10(-3) eV(2), sin(2)2θ(23) = 1 and sin(2)2θ(13) = 0, the expected number of such events is 1.5±0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7×10(-3), equivalent to 2.5σ significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2θ(13) < 0.28(0.34) for δ(CP) = 0 and a normal (inverted) hierarchy.

7.
Pol Merkur Lekarski ; 2(11): 331-5, 1997 May.
Artigo em Polonês | MEDLINE | ID: mdl-9377684

RESUMO

The reviews is a description of one group of cytostatics, namely anthracyclines. It presents a short characteristic of all anthracyclines applied as chemotherapeutic drugs in oncology since many years, and also those which are in the phase of clinical trials. The authors have focused on pharmacodynamics, mechanisms of action, and main side effects, and also the therapeutic use of the particular drugs.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Adulto , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Criança , Ensaios Clínicos como Assunto , Humanos
8.
Acta Pol Pharm ; 53(6): 425-30, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9415217

RESUMO

5-Ethoxalyl 4-methyl-1H-2,3,4,5-tetrahydro 1,5-benzodiazepin-2 -one [I] and 5-ethoxymalonyl-4-methyl-1H-2,3,4,5-tetrahydro-1,5-benzodiazepi n-2-one [IV] were subjected to transesterification using alcohols (propanol, butanol, pentanol) giving derivatives II-IV, VII, VIII. The derivatives I and VI were caused to undergo ammonolysis giving 4-methyl-5-oxamoyl-1H-2,3,4,5 tetrahydro 1,5-benzodiazepin-2-one [V] and 5-malonamoyl-4-methyl-1H-2,3,4,5-tetrahydro-1,5-benzodiazepin++ +-2-one [IX]. The compounds I-IX were tested towards their psychotropic activity. The preparates I, III and V had an anxiolytic action in the four-plate test. The anxiolytic properties of the compound V were confirmed in the test of the black-white box. The antagonism of all investigated compounds for toward reserpine, first of all of the preparations III, IV, V and IX, indicates an antidepressive activity dependent on a stimulation of the adrenergic system.


Assuntos
Ansiolíticos/síntese química , Benzodiazepinonas/síntese química , Animais , Benzodiazepinonas/farmacologia , Sistema Nervoso Central/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Dose Letal Mediana , Masculino , Camundongos , Ratos , Ratos Wistar
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