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Results for Channel Error Profiles for DECT
This letter presents the main statistical characterization
of the underlying error process obtained in the case of
the Digital European Cordless Telecommunications (DECT) radio
system. By simulation of the transmission link, error sequences
are generated for different channel parameters. Relevant statistics
are then computed for the purpose of efficient channel coding
design and evaluation
Vortex line topology during vortex tube reconnection
This paper addresses reconnection of vortex tubes, with particular focus on
the topology of the vortex lines (field lines of the vorticity). This analysis
of vortex line topology reveals previously undiscovered features of the
reconnection process, such as the generation of many small flux rings, formed
when reconnection occurs in multiple locations in the vortex sheet between the
tubes. Consideration of three-dimensional reconnection principles leads to a
robust measurement of the reconnection rate, even once instabilities break the
symmetry. It also allows us to identify internal reconnection of vortex lines
within the individual vortex tubes. Finally, the introduction of a third vortex
tube is shown to render the vortex reconnection process fully
three-dimensional, leading to a fundamental change in the topological structure
of the process. An additional interesting feature is the generation of
vorticity null points.Comment: Accepted for publication in Physical Review Fluid
Intra-arterial thrombolysis of occluded middle cerebral artery by use of collateral pathways in patients with tandem cervical carotid artery/middle cerebral artery occlusion
BACKGROUND AND PURPOSE: Cervical internal carotid artery (ICA) occlusion with middle cerebral artery (MCA) embolic occlusion is associated with a low rate of recanalization and poor outcome after intravenous thrombolysis. Prompt revascularization is required to prevent disabling stroke. We report our experience on acute ischemic stroke patients with tandem ICA or MCA occlusions treated with microcathether navigation and intra-arterial thrombolysis by use of collateral pathways including the posterior or anterior communicating arteries, or both pathways. MATERIALS AND METHODS: We retrospectively identified 8 patients with proximal ICA occlusion associated with MCA embolic occlusions treated with intra-arterial thrombolysis (IA rtPA). Access to the occluded MCA was obtained via catheter navigation through intact collateral pathways, including posterior communicating (PcomA) or anterior communicating (AcomA) arteries, without passing a microcathether through the acutely occluded ICA. We assessed clinical outcomes using modified Rankin scale (mRS) and National Institutes of Health Stroke Scale (NIHSS). RESULTS: Eight patients with a mean age of 57 ± 4 years and median NIHSS of 14 were identified. Mean time from stroke onset to intra-arterial thrombolysis was 292 ± 44 minutes. The MCA was revascularized completely in 5 of the 8 patients via collateral intra-arterial rtPA administration. All of the patients had a favorable outcome defined as a mRS of ≤2 or more at 1 and 3 months\u27 follow-up after thrombolytic therapy. One patient had an asymptomatic petechial hemorrhage. CONCLUSION: In this small number of patients with tandem occlusions of the ICA and MCA, intraarterial thrombolysis and recanalization of the MCA by use of collateral pathways to bypass the occluded ICA is a safe and efficacious therapeutic option
Detection of interstellar hydrogen peroxide
The molecular species hydrogen peroxide, HOOH, is likely to be a key
ingredient in the oxygen and water chemistry in the interstellar medium. Our
aim with this investigation is to determine how abundant HOOH is in the cloud
core {\rho} Oph A. By observing several transitions of HOOH in the
(sub)millimeter regime we seek to identify the molecule and also to determine
the excitation conditions through a multilevel excitation analysis. We have
detected three spectral lines toward the SM1 position of {\rho} Oph A at
velocity-corrected frequencies that coincide very closely with those measured
from laboratory spectroscopy of HOOH. A fourth line was detected at the
4{\sigma} level. We also found through mapping observations that the HOOH
emission extends (about 0.05 pc) over the densest part of the {\rho} Oph A
cloud core. We derive an abundance of HOOH relative to that of H_2 in the SM1
core of about 1\times10^(-10). To our knowledge, this is the first reported
detection of HOOH in the interstellar medium.Comment: 5 pages, 4 figures, accepted for publication in Astronomy &
Astrophysics, new version corrects a typo in Table 1 (and consequently in Fig
4
Transient vortex events in the initial value problem for turbulence
A vorticity surge event that could be a paradigm for a wide class of bursting
events in turbulence is studied to examine how the energy cascade is
established and how this event could serve as a new test of LES turbulence
models. This vorticity surge event is tied to the formation of the energy
cascade in a direct numerical simulation by the traditional signatures of a
turbulent energy cascade such as spectra approaching -5/3 and strongly
Beltramized vortex tubes. A coherent mechanism is suggested by the nearly
simultaneous development of a maximum of the peak vorticity
, growth of the dissipation, the appearance of a helically
aligned local vortex configuration and strong, transient oscillations in the
helicity wavenumber spectrum. This coherence is also examined for two LES
models, a traditional purely dissipative eddy viscosity model and a modern
method (LANS) that respects the nonlinear transport properties of
fluids. Both LES models properly represent the spectral energy and energy
dissipation associated with this vorticity surge event. However, only the model
that preserves nonlinear fluid transport properties reproduces the helical
properties, including Beltrami-like vortex tubes.Comment: 4 pages, 6 figure
Minocycline rescues decrease in neurogenesis, increase in microglia cytokines and deficits in sensorimotor gating in an animal model of schizophrenia
Adult neurogenesis in the hippocampus is impaired in schizophrenic patients and in an animal model of schizophrenia. Amongst a plethora of regulators, the immune system has been shown repeatedly to strongly modulate neurogenesis under physiological and pathological conditions. It is well accepted, that schizophrenic patients have an aberrant peripheral immune status, which is also reflected in the animal model. The microglia as the intrinsic immune competent cells of the brain have recently come into focus as possible therapeutic targets in schizophrenia. We here used a maternal immune stimulation rodent model of schizophrenia in which polyinosinic-polycytidilic acid (Poly I:C) was injected into pregnant rats to mimic an anti-viral immune response. We identified microglia IL-1{beta} and TNF-{alpha} increase constituting the factors correlating best with decreases in net-neurogenesis and impairment in pre-pulse inhibition of a startle response in the Poly I:C model. Treatment with the antibiotic minocycline (3mg/kg/day) normalized microglial cytokine production in the hippocampus and rescued neurogenesis and behavior. We could also show that enhanced microglial TNF-{alpha} and IL-1{beta} production in the hippocampus was accompanied by a decrease in the pro-proliferative TNFR2 receptor expression on neuronal progenitor cells, which could be attenuated by minocycline. These findings strongly support the idea to use anti-inflammatory drugs to target microglia activation as an adjunctive therapy in schizophrenic patients
Distribution and consequences of VKORC1 polymorphisms in Germany
Runge, M., Von Keyserlingk, M., Braune, S., Freise, J., Eiler, T., Plenge-Bönig, A., Becker, D., Pelz, H.-J., Esther, A., Rost, S., Müller, C.R
Nanoscopic Tunneling Contacts on Mesoscopic Multiprobe Conductors
We derive Bardeen-like expressions for the transmission probabilities between
two multi-probe mesoscopic conductors coupled by a weak tunneling contact. We
emphasize especially the dual role of a weak coupling contact as a current
source and sink and analyze the magnetic field symmetry. In the limit of a
point-like tunneling contact the transmission probability becomes a product of
local, partial density of states of the two mesoscopic conductors. We present
expressions for the partial density of states in terms of functional
derivatives of the scattering matrix with respect to the local potential and in
terms of wave functions. We discuss voltage measurements and resistance
measurements in the transport state of conductors. We illustrate the theory for
the simple case of a scatterer in an otherwise perfect wire. In particular, we
investigate the development of the Hall-resistance as measured with weak
coupling probes.Comment: 10 pages, 5 figures, revte
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