684 research outputs found
p73 deficiency results in impaired self renewal and premature neuronal differentiation of mouse neural progenitors independently of p53
10 p.-5 fig.The question of how neural progenitor cells maintain its self-renewal throughout life is a fundamental problem in cell biology with
implications in cancer, aging and neurodegenerative diseases. In this work, we have analyzed the p73 function in embryonic
neural progenitor cell biology using the neurosphere (NS)-assay and showed that p73-loss has a significant role in the
maintenance of neurosphere-forming cells in the embryonic brain. A comparative study of NS from Trp73-/-, p53KO, p53KO;Trp73-/-and their wild-type counterparts demonstrated that p73 deficiency results in two independent, but related, phenotypes: a smaller NS size (related to the proliferation and survival of the neural-progenitors) and a decreased capacity to
form NS (self-renewal). The former seems to be the result of p53 compensatory activity, whereas the latter is p53 independent.
We also demonstrate that p73 deficiency increases the population of neuronal progenitors ready to differentiate into neurons at the expense of depleting the pool of undifferentiated neurosphere-forming cells. Analysis of the neurogenic niches
demonstrated that p73-loss depletes the number of neural-progenitor cells, rendering deficient niches in the adult mice.
Altogether, our study identifies TP73 as a positive regulator of self-renewal with a role in the maintenance of the neurogenic
capacity. Thus, proposing p73 as an important player in the development of neurodegenerative diseases and a potential
therapeutic target.This work was supported by Grants SAF2009-
07897 from Spanish Ministerio de Ciencia e Innovacion (to MCM), Grant from Cajas de Ahorro de Castilla y León (to MCM), and Grants LE030A07 (to MMM) and
LE015A10-2 (to MCM) from the Junta de Castilla y León.Peer reviewe
Kalman filter tracking and vertexing in a silicon detector for neutrino physics
This article describes the application of Kalman filter techniques for the tracking and vertexing of particles inside the NOMAD-STAR detector a silicon vertex detector installed in NOMAD, one of the neutrino oscillation experiments at the CERN-SPS. The use of the Kalman filter simplifies computationally the tracking and vertex procedure for NOMAD-STAR. The alignment of NOMAD-STAR is shown as an example of the application of the Kalman filter for tracking purposes. The accuracy of the method is such that one obtains alignment residuals between 9 and 12~m. Furthermore, a preliminary measure of the impact parameter (with an RMS m) illustrates the vertexing capabilities of this technique
Performance of Long Modules of Silicon Microstrip Detectors
This note describes the performance of modules assembled with up to twelve silicon microstrip detectors. These modules were built for the instrumented Silicon Target (STAR) that has been installed in the NOMAD spectrometer. Laboratory and test beam results are compared with model predictions. For a module of nine detectors, test beam results indicate a signal--to--noise ratio of 19, a hit finding efficiency of 99.8\% and a spatial resolution of 6.0 m. Laboratory measurements indicate that modules of twelve detectors exhibit a signal--to--noise ratio of the order of 16
A multi-site study on walkability, data sharing and privacy perception using mobile sensing data gathered from the mk-sense platform
Walking is a fundamental part of a physically active lifestyle, it is one of everyday activities that positively impacts health and wellbeing. In this paper we describe the challenges and experiences of conducting a sensing campaign in the wild. We make use of mk-sense; a software platform to facilitate the deployment of collaborative sensing campaigns. We elaborate on two cross-cultural studies conducted in four different countries (Mexico, Turkey, Spain, and Switzerland) with a total of 77 participants. We present a detailed description of the data collected from one of the studies aimed at measuring walkability around three different university campuses. The analysis of the data shows that walkability can be assessed using information from the sensors in the smartphones and results from surveys answered by participants. In addition, we analyze issues about data sharing and privacy awareness
Search for the exotic resonance in the NOMAD experiment
A search for exotic Theta baryon via Theta -> proton +Ks decay mode in the
NOMAD muon neutrino DIS data is reported. The special background generation
procedure was developed. The proton identification criteria are tuned to
maximize the sensitivity to the Theta signal as a function of xF which allows
to study the Theta production mechanism. We do not observe any evidence for the
Theta state in the NOMAD data. We provide an upper limit on Theta production
rate at 90% CL as 2.13 per 1000 of neutrino interactions.Comment: Accepted to European Physics Journal
A Precise Measurement of the Muon Neutrino-Nucleon Inclusive Charged Current Cross-Section off an Isoscalar Target in the Energy Range 2.5 < E_\nu < 40 GeV by NOMAD
We present a measurement of the muon neutrino-nucleon inclusive charged
current cross-section, off an isoscalar target, in the neutrino energy range
GeV. The significance of this measurement is its
precision, % in GeV, and % in GeV regions, where significant uncertainties in previous
experiments still exist, and its importance to the current and proposed long
baseline neutrino oscillation experiments.Comment: 14 pages, 3 figures, submitted to Phys.Lett.
Prediction of Neutrino Fluxes in the NOMAD Experiment
The method developed for the calculation of the flux and composition of the
West Area Neutrino Beam used by NOMAD in its search for neutrino oscillations
is described. The calculation is based on particle production rates computed
using a recent version of FLUKA and modified to take into account the cross
sections measured by the SPY and NA20 experiments. These particles are
propagated through the beam line taking into account the material and magnetic
fields they traverse. The neutrinos produced through their decays are tracked
to the NOMAD detector. The fluxes of the four neutrino flavours at NOMAD are
predicted with an uncertainty of about 8% for nu(mu) and nu(e), 10% for
antinu(mu), and 12% for antinu(e). The energy-dependent uncertainty achieved on
the R(e, mu) prediction needed for a nu(mu)->nu(e) oscillation search ranges
from 4% to 7%, whereas the overall normalization uncertainty on this ratio is
4.2%.Comment: 43 pages, 20 figures. Submitted to Nucl. Phys.
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