64 research outputs found
Clues from joint inversion of tsunami and geodetic data of the 2011 Tohoku-oki earthquake
The 2011 Tohoku-oki (Mw 9.1) earthquake is so far the best-observed megathrust rupture, which allowed the collection of unprecedented offshore data. The joint inversion of tsunami waveforms (DART buoys, bottom pressure sensors, coastal wave gauges, and GPS-buoys) and static geodetic data (onshore GPS, seafloor displacements obtained by a GPS/acoustic combination technique), allows us to retrieve the slip distribution on a non-planar fault. We show that the inclusion of near-source data is necessary to image the details of slip pattern (maximum slip ~48 m, up to ~35 m close to the Japan trench), which generated the large and shallow seafloor coseismic deformations and the devastating inundation of the Japanese coast. We investigate the relation between the spatial distribution of previously inferred interseismic coupling and coseismic slip and we highlight the importance of seafloor geodetic measurements to constrain the interseismic coupling, which is one of the key-elements for long-term earthquake and tsunami hazard assessment
Rheological profile across the NE Japan interplate megathrust in the source region of the 2011 Mw9.0 Tohoku-oki earthquake
Preconditioning-induced ischemic tolerance: a window into endogenous gearing for cerebroprotection
Ischemic tolerance defines transient resistance to lethal ischemia gained by a prior sublethal noxious stimulus (i.e., preconditioning). This adaptive response is thought to be an evolutionarily conserved defense mechanism, observed in a wide variety of species. Preconditioning confers ischemic tolerance if not in all, in most organ systems, including the heart, kidney, liver, and small intestine. Since the first landmark experimental demonstration of ischemic tolerance in the gerbil brain in early 1990's, basic scientific knowledge on the mechanisms of cerebral ischemic tolerance increased substantially. Various noxious stimuli can precondition the brain, presumably through a common mechanism, genomic reprogramming. Ischemic tolerance occurs in two temporally distinct windows. Early tolerance can be achieved within minutes, but wanes also rapidly, within hours. Delayed tolerance develops in hours and lasts for days. The main mechanism involved in early tolerance is adaptation of membrane receptors, whereas gene activation with subsequent de novo protein synthesis dominates delayed tolerance. Ischemic preconditioning is associated with robust cerebroprotection in animals. In humans, transient ischemic attacks may be the clinical correlate of preconditioning leading to ischemic tolerance. Mimicking the mechanisms of this unique endogenous protection process is therefore a potential strategy for stroke prevention. Perhaps new remedies for stroke are very close, right in our cells
Measurements of the branching fractions for decays at Belle II
This paper reports a study of decays using
fb of data collected during 2019--2020 by the Belle II experiment at the
SuperKEKB asymmetric-energy collider, corresponding to events. We find , ,
, and signal events in the decay modes , ,
, and , respectively. The uncertainties quoted for the
signal yield are statistical only. We report the branching fractions of these
decays: where the first
uncertainty is statistical, and the second is systematic. The results are
consistent with world-average values
Measurement of the integrated luminosity of the Phase 2 data of the Belle II experiment
From April to July 2018, a data sample at the peak energy of the γ(4S) resonance was collected with the Belle II detector at the SuperKEKB electron-positron collider. This is the first data sample of the Belle II experiment. Using Bhabha and digamma events, we measure the integrated luminosity of the data sample to be (496.3 ± 0.3 ± 3.0) pb-1, where the first uncertainty is statistical and the second is systematic. This work provides a basis for future luminosity measurements at Belle II
Precise Measurement of the D and D Lifetimes at Belle II
We report a measurement of the D and D lifetimes using D→Kπ and D→Kππ decays reconstructed in ee→ data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy ee collider. The data, collected at center-of-mass energies at or near the Υ(4S) resonance, correspond to an integrated luminosity of 72 fb. The results, τ(D)=410.5±1.1(stat)±0.8(syst) fs and τ(D)=1030.4±4.7(stat)±3.1(syst) fs, are the most precise to date and are consistent with previous determinations
Observation of decays using the 2019-2022 Belle II data sample
We present a measurement of the branching fractions of four decay modes. The measurement is based on data from
SuperKEKB electron-positron collisions at the resonance
collected with the Belle II detector and corresponding to an integrated
luminosity of . The event yields are extracted from fits
to the distributions of the difference between expected and observed meson
energy to separate signal and background, and are efficiency-corrected as a
function of the invariant mass of the system. We find the branching
fractions to be: where the first uncertainty is statistical and
the second systematic. These results include the first observation of
, , and decays and a significant improvement in the precision
of compared to previous measurements
Determination of from untagged decays using 2019-2021 Belle II data
We present an analysis of the charmless semileptonic decay , where , from 198.0 million pairs of
mesons recorded by the Belle II detector at the SuperKEKB
electron-positron collider. The decay is reconstructed without identifying the
partner meson. The partial branching fractions are measured independently
for and as functions of
(momentum transfer squared), using 3896 and
5466 decays. The total branching fraction is
found to be for decays, where the uncertainties are statistical and
systematic, respectively. By fitting the measured partial branching fractions
as functions of , together with constraints on the nonperturbative
hadronic contribution from lattice QCD calculations, the magnitude of the
Cabibbo-Kobayashi-Maskawa matrix element , , is extracted. Here, the first uncertainty is
statistical, the second is systematic and the third is theoretical
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