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1.
Eur Phys J C Part Fields ; 81(4): 322, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720713

RESUMEN

The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM). Of the many potential beyond the Standard Model (BSM) topics DUNE will probe, this paper presents a selection of studies quantifying DUNE's sensitivities to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and significantly extend the present reach.

2.
Sci Data ; 8(1): 218, 2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34385471

RESUMEN

The OPERA experiment was designed to discover the vτ appearance in a vµ beam, due to neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of a nuclear photographic emulsion/lead target with a mass of about 1.25 kt, complemented by electronic detectors. It was exposed from 2008 to 2012 to the CNGS beam: an almost pure vµ beam with a baseline of 730 km, collecting a total of 1.8·1020 protons on target. The OPERA Collaboration eventually assessed the discovery of vµâ†’vτ oscillations with a statistical significance of 6.1 σ by observing ten vτ CC interaction candidates. These events have been published on the Open Data Portal at CERN. This paper provides a detailed description of the vτ data sample to make it usable by the whole community.

3.
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.

4.
Respir Med Case Rep ; 30: 101035, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32190545

RESUMEN

Mucormycosis is a life-threatening infectious disease that occurs most commonly in immunocompromised patients such as those with hematological malignancies. Its clinical symptoms and associated radiological findings vary and specific biomarkers and culture characteristics have not been defined. An 85-year-old man who had been treated for myelodysplastic syndrome and tuberculosis for several months presented with subacute fever and worsening left-side chest pain. Contrast-enhanced computed tomography images depicted massive tumor-like consolidation without enhancement, expanding from the left lower lobe. Emboli that did not respond to anticoagulants were detected in the left descending pulmonary artery. Despite intensive treatment he developed multiple organ failure and died 47 days after hospitalization. Gross pathology of a lung autopsy specimen revealed left lower pulmonary arterial emboli and pulmonary infarction, which was concluded to be the direct cause of death. The emboli were histopathologically identified as invasive mycelia in vessels. Mucor sp. was detected via real-time polymerase chain reaction and immunohistopathological analyses revealed that the mold in the blood vessels of lung tissue was partially positive for the mucor antigen. In the present case of Mucor sp. pulmonary emboli in a patient with myelodysplastic syndrome, radiographic findings were hard to distinguish from those typical of a lung abscess.

5.
Sci Adv ; 5(5): eaav7610, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31058223

RESUMEN

Interference of matter waves is at the heart of quantum physics and has been observed for a wide range of particles from electrons to complex molecules. Here, we demonstrate matter wave interference of single positrons using a period-magnifying Talbot-Lau interferometer based on material diffraction gratings. The system produced high-contrast periodic fringes, which were detected by means of nuclear emulsions capable of determining the impact point of each individual positron with submicrometric resolution. The measured energy dependence of fringe contrast in the range of 8 to 16 keV proves the quantum-mechanical origin of the periodic pattern and excludes classical projective effects, providing the first observation to date of antimatter wave interference. Future applications of this interferometric technique include the measurement of the gravitational acceleration of neutral antimatter systems exploiting the inertial sensing capabilities of Talbot-Lau interference.

6.
Sci Rep ; 9(1): 6970, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31061450

RESUMEN

Mountain glaciers form landscapes with U-shaped valleys, roche moutonées and overdeepenings through bedrock erosion. However, little evidence for active glacial carving has been provided particularly for areas above the Equilibrium Line Altitude (ELA) where glaciers originate. This is mainly due to our lack of information about the shape of the bedrock underneath active glaciers in highly elevated areas. In the past years, the bedrock morphology underneath active glaciers has been studied by geophysical methods in order to infer the subglacial mechanisms of bedrock erosion. However, these comprise surveys on the glaciers' surface, from where it has been difficult to investigate the lateral boundary between the ice and the bedrock with sufficient resolution. Here we perform a muon-radiographic inspection of the Eiger glacier (Switzerland, European Alps) with the aid of cosmic-ray muon attenuation. We find a reach (600 × 300 m) within the accumulation area where strong lateral glacial erosion has cut nearly vertically into the underlying bedrock. This suggests that the Eiger glacier has profoundly sculpted its bedrock in its accumulation area. This also reveals that the cosmic-ray muon radiography is an ideal technology to reconstruct the shape of the bedrock underneath an active glacier.

7.
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}.

8.
Phys Rev Lett ; 120(21): 211801, 2018 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-29883136

RESUMEN

The OPERA experiment was designed to study ν_{µ}→ν_{τ} oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×10^{19} protons on target. Selection criteria looser than in previous analyses have produced ten ν_{τ} candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ν_{τ} properties. A multivariate approach for event identification has been applied to the candidate events and the discovery of ν_{τ} appearance is confirmed with an improved significance level of 6.1σ. |Δm_{32}^{2}| has been measured, in appearance mode, with an accuracy of 20%. The measurement of the ν_{τ} charged-current cross section, for the first time with a negligible contamination from ν[over ¯]_{τ}, and the first direct evidence for the ν_{τ} lepton number are also reported.

9.
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.

10.
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.

11.
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.

12.
Phys Rev Lett ; 115(12): 121802, 2015 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-26430986

RESUMEN

The OPERA experiment was designed to search for ν_{µ}→ν_{τ} oscillations in appearance mode, i.e., by detecting the τ leptons produced in charged current ν_{τ} interactions. The experiment took data from 2008 to 2012 in the CERN Neutrinos to Gran Sasso beam. The observation of the ν_{µ}→ν_{τ} appearance, achieved with four candidate events in a subsample of the data, was previously reported. In this Letter, a fifth ν_{τ} candidate event, found in an enlarged data sample, is described. Together with a further reduction of the expected background, the candidate events detected so far allow us to assess the discovery of ν_{µ}→ν_{τ} oscillations in appearance mode with a significance larger than 5σ.

13.
Phys Rev Lett ; 113(24): 241803, 2014 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-25541766

RESUMEN

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.

14.
Nat Commun ; 5: 4538, 2014 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-25066810

RESUMEN

The precise measurement of forces is one way to obtain deep insight into the fundamental interactions present in nature. In the context of neutral antimatter, the gravitational interaction is of high interest, potentially revealing new forces that violate the weak equivalence principle. Here we report on a successful extension of a tool from atom optics--the moiré deflectometer--for a measurement of the acceleration of slow antiprotons. The setup consists of two identical transmission gratings and a spatially resolving emulsion detector for antiproton annihilations. Absolute referencing of the observed antimatter pattern with a photon pattern experiencing no deflection allows the direct inference of forces present. The concept is also straightforwardly applicable to antihydrogen measurements as pursued by the AEgIS collaboration. The combination of these very different techniques from high energy and atomic physics opens a very promising route to the direct detection of the gravitational acceleration of neutral antimatter.

15.
Phys Rev Lett ; 112(18): 181801, 2014 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-24856687

RESUMEN

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.

16.
Phys Rev Lett ; 112(6): 061802, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24580687

RESUMEN

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.

17.
Phys Rev Lett ; 111(21): 211803, 2013 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-24313479

RESUMEN

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.

18.
Phys Rev Lett ; 107(4): 041801, 2011 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-21866992

RESUMEN

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.

19.
Bioorg Med Chem Lett ; 10(9): 865-9, 2000 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-10853648

RESUMEN

In order to develop new inhibitors of NF-kappaB activation, we designed and synthesized dehydroxymethyl derivatives of epoxyquinomicin C, namely, DHM2EQ and its regioisomer DHM3EQ. These derivatives were synthesized from 2,5-dimethoxyaniline in 5 steps. Since DHM2EQ was more active and less toxic than DHM3EQ, its stereochemical configuration was determined by X-ray crystallographic analysis. Each enantiomer of the protected DHM2EQ was separated by a chiral column and deprotected. DHM2EQ inhibited TNF-alpha-induced activation of NF-kappaB in human T cell leukemia cells, and also inhibited collagen-induced arthritis in a rheumatoid model in mice.


Asunto(s)
Antineoplásicos/química , Benzamidas/química , FN-kappa B/antagonistas & inhibidores , Quinonas/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Antirreumáticos/síntesis química , Antirreumáticos/farmacología , Artritis Reumatoide/inducido químicamente , Artritis Reumatoide/prevención & control , Benzamidas/síntesis química , Benzamidas/farmacología , Biotransformación/efectos de los fármacos , Dicroismo Circular , Humanos , Células Jurkat , Espectroscopía de Resonancia Magnética , Ratones , Oxidación-Reducción , Quinonas/síntesis química , Quinonas/farmacología , Estereoisomerismo , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/metabolismo
20.
Anticancer Drug Des ; 15(4): 239-44, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11200499

RESUMEN

Nuclear factor (NF)-kappaB is a transcription factor that induces the immunoglobulin kappa chain, cytokines such as interleukin (IL)-1, IL-2, IL-6, IL-8, tumor necrosis factor (TNF)-alpha and interferon gamma, and cell adhesion proteins. It also induces anti-apoptotic proteins, and inhibits TNF-alpha and anticancer drug-induced apoptosis. Therefore, NF-kappaB function inhibitors may be useful as anti-inflammatory and anticancer agents. Microbial products such as panepoxydone, cycloepoxydon and gliotoxin are known to inhibit activation of NF-kappaB. We have designed and synthesized new NF-kappaB inhibitors from the structure of an antibiotic, epoxyquinomicin C. The designed compound, DHM2EQ, inhibited TNF-alpha-induced activation of NF-kappaB and showed a therapeutic effect in mouse rheumatoid arthritis model.


Asunto(s)
Antineoplásicos/farmacología , FN-kappa B/antagonistas & inhibidores , Animales , Antibióticos Antineoplásicos/aislamiento & purificación , Antibióticos Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/aislamiento & purificación , Diseño de Fármacos , Humanos , FN-kappa B/fisiología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
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