2,208 research outputs found
Magnetic fluctuation and cosmic ray diurnal variations
A unified theory of cosmic ray diurnal variations has been proposed in which the first 3 harmonics of the cosmic ray daily variation all results from a single anisotropy produced by the combined effects of adiabatic focusing and anisotropic pitch angle scattering. The theoretical description of steady state cosmic ray anisotropies are simplified and improved. Preliminary results of a study of correlations between cosmic ray diurnal variations and the fluctuation characteristics of the interplanetary magnetic field are presented and discussed in light of the theory
Gd(III)-Gd(III) Relaxation-Induced Dipolar Modulation Enhancement for In-Cell Electron Paramagnetic Resonance Distance Determination
In-cell distance determination by electron paramagnetic resonance (EPR) spectroscopy reveals essential structural information about biomacromolecules under native conditions. We demonstrate that the pulsed EPR technique RIDME (relaxation induced dipolar modulation enhancement) can be utilized for such distance determination. The performance of in-cell RIDME has been assessed at Q-band using stiff molecular rulers labeled with Gd(III)-PyMTA and microinjected into Xenopus laevis oocytes. The overtone coefficients are determined to be the same for protonated aqueous solutions and inside cells. As compared to in-cell DEER (double electron-electron resonance, also abbreviated as PELDOR), in-cell RIDME features approximately 5 times larger modulation depth and does not show artificial broadening in the distance distributions due to the effect of pseudosecular terms
Exponential anisotropy of solar cosmic rays
On 16 February 1984 a flare on the Sun's invisible disk produced a large, highly anisotropic solar particle event. A technique, in which interplanetary scattering parameters are determined purely from the form of the particle anisotropy, is applied to energetic particle data from neutron monitors and the ICE spacecraft
HLA-G: expression in human keratinocytes in vitro and in human skin in vivo
Classical, polymorphic major histocompatibility complex class I molecules are
expressed on most nucleated cells.They present peptides at the cell surface and,
thus, enable the immune system to scan peptides for their antigenicity. The
function of the other, nonclassical class I molecules in man is controversial.
HLA-G which has been shown by transfection experiments to be expressed at the
cell surface, is only transcribed in placental tissue and in the fetal eye.Therefore, a
role of HLA-G in the control of rejection of the allogeneic fetus has been
discussed. We found that HLA-G expression is induced in keratinocytes by
culture in vitro. Three different alternative splicing products of HLA-G can be
detected: a full length transcript, an mRNA lacking exon 3 and a transcript devoid
of exon 3 and 4. Reverse transcription followed by polymerase chain reaction also
revealed the presence of HLA-G mRNA in vivo in biopsies of either diseased or
healthy skin
Diffusion of energetic particles in turbulent MHD plasmas
In this paper we investigate the transport of energetic particles in
turbulent plasmas. A numerical approach is used to simulate the effect of the
background plasma on the motion of energetic protons. The background plasma is
in a dynamically turbulent state found from numerical MHD simulations, where we
use parameters typical for the heliosphere. The implications for the transport
parameters (i.e. pitch-angle diffusion coefficients and mean free path) are
calculated and deviations from the quasi-linear theory are discussed.Comment: Accepted for publication in Ap
The xSAP Safety Analysis Platform
This paper describes the xSAP safety analysis platform. xSAP provides several
model-based safety analysis features for finite- and infinite-state synchronous
transition systems. In particular, it supports library-based definition of
fault modes, an automatic model extension facility, generation of safety
analysis artifacts such as Dynamic Fault Trees (DFTs) and Failure Mode and
Effects Analysis (FMEA) tables. Moreover, it supports probabilistic evaluation
of Fault Trees, failure propagation analysis using Timed Failure Propagation
Graphs (TFPGs), and Common Cause Analysis (CCA). xSAP has been used in several
industrial projects as verification back-end, and is currently being evaluated
in a joint R&D Project involving FBK and The Boeing Company
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