The shower simulation code CORSIKA has been used to investigate the electron energy and angular distributions in high-energy showers. Based on the universality of both distributions, we develop an ...analytical description of Cherenkov light emission in extensive air showers, which provides the total number and angular distribution of photons. The parameterisation can be used e.g. to calculate the contribution of direct and scattered Cherenkov light to shower profiles measured with the air fluorescence technique.
KASCADE-Grande is an air shower observatory devoted to the detection of cosmic rays in the 1016 – 1018eV energy range. For each event the arrival direction, the total number of charged particles ...(Nch) and the total number of muons (Nμ), at detection level (i.e. 110 m a.s.l.), are measured. The detection of these observarbles, with high accuracy, allows the study of the primary spectrum, chemical composition and large scale anisotropies, that are the relevant informations to investigate the astrophysics of cosmic rays in this energy range. These studies are of main importance to deeply investigate the change of slope of the primary spectrum detected at ~ 4 × 1015 eV, also known as the knee, and to search for the transition from galactic to extra-galactic cosmic rays.
Predictions of the hadronic interaction model EPOS 1.61 as implemented in the air shower simulation program CORSIKA are compared to observations with the KASCADE experiment. The investigations reveal ...that the predictions of EPOS are not compatible with KASCADE measurements. The discrepancies seen are most likely due to use of a set of inelastic hadronic cross sections that are too high.
The expression patterns of the neurotrophin, brain-derived neurotrophic factor, BDNF, and the neurotrophic receptors—p75NTR and Trk receptors—in the developing human fetal inner ear between the ...gestational weeks (GW) 9 to 12 are examined via in situ hybridization and immunohistochemistry. BDNF mRNA expression was highest in the cochlea at GW 9 but declined in the course of development. In contrast to embryonic murine specimens, a decline in BDNF expression from the apical to the basal turn of the cochlea could not be observed. p75NTR immunostaining was most prominent in the nerve fibers that penetrate into the sensory epithelia of the cochlea, the urticule and the saccule as gestational age progresses. TrkB and TrkC expression intensified towards GW 12, at which point the BDNF mRNA localization was at its lowest. TrkA expression was limited to fiber subpopulations of the facial nerve at GW 10. In the adult human inner ear, we observed BDNF mRNA expression in the apical poles of the cochlear hair cells and supporting cells, while in the adult human utricle, the expression was localized in the vestibular hair cells. We demonstrate the highly specific staining patterns of BDNF mRNA and its putative receptors over a developmental period in which multiple hearing disorders are manifested. Our findings suggest that BDNF and neurotrophin receptors are important players during early human inner ear development. In particular, they seem to be important for the survival of the afferent sensory neurons.
EURECA Conceptual Design Report Angloher, G.; Armengaud, E.; Augier, C. ...
PHYSICS OF THE DARK UNIVERSE,
April 2014, 2014-04-00, 2014-04, Letnik:
3
Journal Article
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The EURECA (European Underground Rare Event Calorimeter Array) project is aimed at searching for dark matter particles using cryogenic bolometers. The proponents of the present project have decided ...to pool their strengths and expertise to build a facility to house up to 1000 kg of detectors, EURECA, consisting in the first instance of germanium and CaWO4 crystals. The shielding will be provided through a large water tank in which the cryostat with detectors will be immersed. The EURECA infrastructure will be an essential tool for the community interested in using cryogenic detectors for dark matter searches. Beyond European detectors, it will be designed to host other types of similar cryogenic detectors, requiring millikelvin operating temperatures. In particular, this includes the germanium detectors currently in use by the SuperCDMS team, following the current collaborative work performed by the EURECA and SuperCDMS collaborations. EURECA will have two stages. The first phase aims at a sensitivity of 3 . 10−10 pb and will involve building the infrastructure, cryostat and shielding, and operating 150 kg of detectors. The second phase will be completed with 850 kg of additional detectors, the relative weight between the different detectors being decided by the collaboration according to the physics reach. A sensitivity of 2 . 10−11 pb is aimed for at the second stage. EURECA will ideally benefit from the planned extension of the deepest underground laboratory in Europe – LSM. With a site-independent design, it can also be hosted in other locations at similar or deeper sites such as SNOLAB.
With the KASCADE-Grande Muon Tracking Detector it was possible to measure with high accuracy directions of EAS muons with energy above 0.8 GeV and up to 700 m distance from the shower centre. ...Reconstructed muon tracks allow investigation of muon pseudorapidity (η) distributions. These distributions are nearly identical to the pseudorapidity distributions of their parent mesons produced in hadronic interactions. Comparison of the η distributions from measured and simulated showers can be used to test the quality of the high energy hadronic interaction models. The pseudorapidity distributions reflect the longitudinal development of EAS and, as such, are sensitive to the mass of the cosmic ray primary particles. With various parameters of the η distribution, obtained from the Muon Tracking Detector data, it is possible to calculate the average logarithm of mass of the primary cosmic ray particles. The results of the 〈 ln A 〉 analysis in the primary energy range 1016 eV–1017 eV with the 1st quartile and the mean value of the distributions will be presented for the QGSJet-II-2, QGSJet-II-4, EPOS 1.99 and EPOS LHC models in combination with the FLUKA model.
Myeloid cells are known mediators of hypertension, but their role in initiating renin-induced hypertension has not been studied. Vitamin D deficiency causes pro-inflammatory macrophage infiltration ...in metabolic tissues and is linked to renin-mediated hypertension. We tested the hypothesis that impaired vitamin D signaling in macrophages causes hypertension using conditional knockout of the myeloid vitamin D receptor in mice (KODMAC). These mice develop renin-dependent hypertension due to macrophage infiltration of the vasculature and direct activation of renal juxtaglomerular (JG) cell renin production. Induction of endoplasmic reticulum stress in knockout macrophages increases miR-106b-5p secretion, which stimulates JG cell renin production via repression of transcription factors E2f1 and Pde3b. Moreover, in wild-type recipient mice of KODMAC/miR106b
bone marrow, knockout of miR-106b-5p prevents the hypertension and JG cell renin production induced by KODMAC macrophages, suggesting myeloid-specific, miR-106b-5p-dependent effects. These findings confirm macrophage miR-106b-5p secretion from impaired vitamin D receptor signaling causes inflammation-induced hypertension.
Activation of heterotrimeric G proteins is a key step in many signaling cascades. However, a complete mechanism for this process, which requires allosteric communication between binding sites that ...are ~30 Å apart, remains elusive. We construct an atomically detailed model of G protein activation by combining three powerful computational methods: metadynamics, Markov state models (MSMs), and CARDS analysis of correlated motions. We uncover a mechanism that is consistent with a wide variety of structural and biochemical data. Surprisingly, the rate-limiting step for GDP release correlates with tilting rather than translation of the GPCR-binding helix 5. β-Strands 1 - 3 and helix 1 emerge as hubs in the allosteric network that links conformational changes in the GPCR-binding site to disordering of the distal nucleotide-binding site and consequent GDP release. Our approach and insights provide foundations for understanding disease-implicated G protein mutants, illuminating slow events in allosteric networks, and examining unbinding processes with slow off-rates.
We report on the measurement of microwave radio signals from air showers with the CROME (Cosmic Ray Observation via Microwave Emission) experiment. CROME is located in the center of the ...KASCADE-Grande air shower array. The radio signals of the CROME antennas are stored for each high-energy trigger from the KASCADE-Grande array and matched offine with the KASCADE-Grande data. After almost one year of data taking microwave signals have been observed for more than ten air showers.
KASCADE-Grande is a large detector array for observations of the energy spectrum as well as the chemical composition of cosmic ray air showers up to primary energies of 1 EeV. The multi-detector ...arrangement allows to measure the electromagnetic and muonic components for individual air showers. In this analysis, the reconstruction of the all-particle energy spectrum is based on the size spectra of the charged particle component. The energy is calibrated by using Monte Carlo simulations performed with CORSIKA and high-energy interaction models QGSJet, EPOS and SIBYLL. In all cases FLUKA has been used as low-energy interaction model. In this contribution the resulting spectra by means of different hadronic interaction models will be compared and discussed.
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