1,296 research outputs found
Features of Muon Arrival Time Distributions of High Energy EAS at Large Distances From the Shower Axis
In view of the current efforts to extend the KASCADE experiment
(KASCADE-Grande) for observations of Extensive Air Showers (EAS) of primary
energies up to 1 EeV, the features of muon arrival time distributions and their
correlations with other observable EAS quantities have been scrutinised on
basis of high-energy EAS, simulated with the Monte Carlo code CORSIKA and using
in general the QGSJET model as generator. Methodically various correlations of
adequately defined arrival time parameters with other EAS parameters have been
investigated by invoking non-parametric methods for the analysis of
multivariate distributions, studying the classification and misclassification
probabilities of various observable sets. It turns out that adding the arrival
time information and the multiplicity of muons spanning the observed time
distributions has distinct effects improving the mass discrimination. A further
outcome of the studies is the feature that for the considered ranges of primary
energies and of distances from the shower axis the discrimination power of
global arrival time distributions referring to the arrival time of the shower
core is only marginally enhanced as compared to local distributions referring
to the arrival of the locally first muon.Comment: 24 pages, Journal Physics G accepte
Primary Proton Spectrum of Cosmic Rays measured with Single Hadrons
The flux of cosmic-ray induced single hadrons near sea level has been
measured with the large hadron calorimeter of the KASCADE experiment. The
measurement corroborates former results obtained with detectors of smaller size
if the enlarged veto of the 304 m^2 calorimeter surface is encounted for. The
program CORSIKA/QGSJET is used to compute the cosmic-ray flux above the
atmosphere. Between E_0=300 GeV and 1 PeV the primary proton spectrum can be
described with a power law parametrized as
dJ/dE_0=(0.15+-0.03)*E_0^{-2.78+-0.03} m^-2 s^-1 sr^-1 TeV^-1. In the TeV
region the proton flux compares well with the results from recent measurements
of direct experiments.Comment: 13 pages, accepted by Astrophysical Journa
Upregulation of the cell-cycle regulator RGC-32 in Epstein-Barr virus-immortalized cells
Epstein-Barr virus (EBV) is implicated in the pathogenesis of multiple human tumours of lymphoid and epithelial origin. The virus infects and immortalizes B cells establishing a persistent latent infection characterized by varying patterns of EBV latent gene expression (latency 0, I, II and III). The CDK1 activator, Response Gene to Complement-32 (RGC-32, C13ORF15), is overexpressed in colon, breast and ovarian cancer tissues and we have detected selective high-level RGC-32 protein expression in EBV-immortalized latency III cells. Significantly, we show that overexpression of RGC-32 in B cells is sufficient to disrupt G2 cell-cycle arrest consistent with activation of CDK1, implicating RGC-32 in the EBV transformation process. Surprisingly, RGC-32 mRNA is expressed at high levels in latency I Burkitt's lymphoma (BL) cells and in some EBV-negative BL cell-lines, although RGC-32 protein expression is not detectable. We show that RGC-32 mRNA expression is elevated in latency I cells due to transcriptional activation by high levels of the differentially expressed RUNX1c transcription factor. We found that proteosomal degradation or blocked cytoplasmic export of the RGC-32 message were not responsible for the lack of RGC-32 protein expression in latency I cells. Significantly, analysis of the ribosomal association of the RGC-32 mRNA in latency I and latency III cells revealed that RGC-32 transcripts were associated with multiple ribosomes in both cell-types implicating post-initiation translational repression mechanisms in the block to RGC-32 protein production in latency I cells. In summary, our results are the first to demonstrate RGC-32 protein upregulation in cells transformed by a human tumour virus and to identify post-initiation translational mechanisms as an expression control point for this key cell-cycle regulator
Contrast Enhanced Micro-Computed Tomography Resolves the 3-Dimensional Morphology of the Cardiac Conduction System in Mammalian Hearts
The general anatomy of the cardiac conduction system (CCS) has been known for 100 years, but its complex and irregular three-dimensional (3D) geometry is not so well understood. This is largely because the conducting tissue is not distinct from the surrounding tissue by dissection. The best descriptions of its anatomy come from studies based on serial sectioning of samples taken from the appropriate areas of the heart. Low X-ray attenuation has formerly ruled out micro-computed tomography (micro-CT) as a modality to resolve internal structures of soft tissue, but incorporation of iodine, which has a high molecular weight, into those tissues enhances the differential attenuation of X-rays and allows visualisation of fine detail in embryos and skeletal muscle. Here, with the use of a iodine based contrast agent (I2KI), we present contrast enhanced micro-CT images of cardiac tissue from rat and rabbit in which the three major subdivisions of the CCS can be differentiated from the surrounding contractile myocardium and visualised in 3D. Structures identified include the sinoatrial node (SAN) and the atrioventricular conduction axis: the penetrating bundle, His bundle, the bundle branches and the Purkinje network. Although the current findings are consistent with existing anatomical representations, the representations shown here offer superior resolution and are the first 3D representations of the CCS within a single intact mammalian heart
EURONEAR - Recovery, Follow-up and Discovery of NEAs and MBAs using Large Field 1-2m Telescopes
We report on the follow-up and recovery of 100 program NEAs, PHAs and VIs
using the ESO/MPG 2.2m, Swope 1m and INT 2.5m telescopes equipped with large
field cameras. The 127 fields observed during 11 nights covered 29 square
degrees. Using these data, we present the incidental survey work which includes
558 known MBAs and 628 unknown moving objects mostly consistent with MBAs from
which 58 objects became official discoveries. We planned the runs using six
criteria and four servers which focus mostly on faint and poorly observed
objects in need of confirmation, follow-up and recovery. We followed 62 faint
NEAs within one month after discovery and we recovered 10 faint NEAs having big
uncertainties at their second or later opposition. Using the INT we eliminated
4 PHA candidates and VIs. We observed in total 1,286 moving objects and we
reported more than 10,000 positions. All data were reduced by the members of
our network in a team effort, and reported promptly to the MPC. The positions
of the program NEAs were published in 27 MPC and MPEC references and used to
improve their orbits. The O-C residuals for known MBAs and program NEAs are
smallest for the ESO/MPG and Swope and about four times larger for the INT
whose field is more distorted. The incidental survey allowed us to study
statistics of the MBA and NEA populations observable today with 1--2m
facilities. We calculate preliminary orbits for all unknown objects,
classifying them as official discoveries, later identifications and unknown
outstanding objects. The orbital elements a, e, i calculated by FIND_ORB
software for the official discoveries and later identified objects are very
similar with the published elements which take into account longer
observational arcs; thus preliminary orbits were used in statistics for the
whole unknown dataset. (CONTINUED)Comment: Accepted in Planetary and Space Science (Aug 2011
Abendland und Wirtschaftswunder. Zur kulturkritischen Physiognomie der westdeutschen Romanprosa zwischen 1945 und 1959
This study in the field of literature deals with seven novels of early Western German postwar-literature: Hermann Kasack, Die Stadt hinter dem Strom (1946); Ernst Kreuder, Die Unauffindbaren (1048); Hans Werner Richter, Die Geschlagenen (1949); Arno Schmidt, Schwarze Spiegel (1951); Wolfgang Koeppen, Tauben im Gras (1951), Das Treibhaus (1953); Heinrich Böll, Billard um halb zehn (1959). The general thesis says that in these representative texts the intellectual Gestalt of holds a key position. Despite of the rhetorics of the (1945) and the self-understandig of the authors as left-wing progressives the novels cling to an intellectual tradition of pre-war Germany that is linked to the anti-dmocratic right-wing opponents of the so-called . The critique of the and the complimentary emphasis of the wirter / intellectual as a leading figure in society are anti-Western issues which are continually re-installed through the authors' concepts of history and their claim of intellectual superiority. Developing a broad concept of analysis combining tools from hermeneutics and the social sciences (), the study points out in neat interpretations how this persistent scheme from the tradition of cultural criticism is working in various layers of the texts. There are detailed readings of the modelling of society, space and characters (esp. female ones); the study takes an additional look on essayistic and poetological passages as well as on Gnostic aspects of the involved cultural criticism
A multi-gene signature predicts outcome in patients with pancreatic ductal adenocarcinoma.
© 2014 Haider et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain
Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article,
unless otherwise stated.Improved usage of the repertoires of pancreatic ductal adenocarcinoma (PDAC) profiles is crucially needed to guide the development of predictive and prognostic tools that could inform the selection of treatment options
Conditional Gene Targeting in Mouse Pancreatic β-Cells: Analysis of Ectopic Cre Transgene Expression in the Brain
B. W. and M. B. Contributed equally to this manuscript Corresponding authors
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