298 research outputs found
Lamotrigine treatment of aggression in female borderline patients, Part II: an 18-month follow-up
Borderline patients often display pathological aggression. We previously tested lamotrigine, an anti-convulsant, in therapy for aggression in women with borderline personality disorder (BPD) (J Psychopharmacol 2005; 19: 287–291), and found significant changes on most scales of the State-Trait Anger Expression Inventory (STAXI) after eight weeks. To assess the longerterm efficacy of lamotrigine in therapy for aggression in women with BPD, this 18-month follow-up observation was carried out, in which patients (treated with lamotrigine: n = 18; former placebo group: n = 9) were tested every six months. According to the intent-to-treat principle, significant changes on all scales of the STAXI were observed in the lamotrigine-treated subjects. All subjects tolerated lamotrigine relatively well. Lamotrigine appears to be an effective and relatively safe agent in the longer-term treatment of aggression in women with BPD
Analytical modeling of HSUPA-enabled UMTS networks for capacity planning
In recent years, mobile communication networks have experienced significant evolution. The 3G mobile communication system, UMTS, employs WCDMA as the air interface standard, which leads to quite different mobile network planning and dimensioning processes compared with 2G systems. The UMTS system capacity is limited by the received interference at NodeBs due to the unique features of WCDMA, which is denoted as `soft capacity'. Consequently, the key challenge in UMTS radio network planning has been shifted from channel allocation in the channelized 2G systems to blocking and outage probabilities computation under the `cell breathing' effects which are due to the relationship between network coverage and capacity. The interference characterization, especially for the other-cell interference, is one of the most important components in 3G mobile networks planning. This monograph firstly investigates the system behavior in the operation of UMTS uplink, and develops the analytic techniques to model interference and system load as fully-characterized random variables, which can be directly applicable to the performance modeling of such networks. When the analysis progresses from single-cell scenario to multi-cell scenario, as the target SIR oriented power control mechanism is employed for maximum capacity, more sophisticated system operation, `feedback behavior', has emerged, as the interference levels at different cells depend on each other. Such behaviors are also captured into the constructed interference model by iterative and approximation approaches. The models are then extended to cater for the features of the newly introduced HSUPA, which provides enhanced dedicated channels for the packet switched data services such that much higher bandwidth can be achieved for best-effort elastic traffic, which allows network operators to cope with the coexistence of both circuit-switched and packet-switched traffic and guarantee the QoS requirements. During the derivation, we consider various propagation models, traffic models, resource allocation schemes for many possible scenarios, each of which may lead to different analytical models. All the suggested models are validated with either Monte-Carlo simulations or discrete event simulations, where excellent matches between results are always achieved. Furthermore, this monograph studies the optimization-based resource allocation strategies in the UMTS uplink with integrated QoS/best-effort traffic. Optimization techniques, both linear-programming based and non-linear-programming based, are used to determine how much resource should be assigned to each enhanced uplink user in the multi-cell environment where each NodeB possesses full knowledge of the whole network. The system performance under such resource allocation schemes are analyzed and compared via Monte-Carlo simulations, which verifies that the proposed framework may serve as a good estimation and optimal reference to study how systems perform for network operators
SWI/SNF remains localized to chromatin in the presence of SCHLAP1
SCHLAP1 is a long noncoding RNA that is reported to function by depleting the SWI/SNF complex from the genome. We investigated the hypothesis that SCHLAP1 affects only specific compositions of SWI/SNF. Using several assays, we found that SWI/SNF is not depleted from the genome by SCHLAP1 and that SWI/SNF is associated with many coding and noncoding RNAs, suggesting that SCHLAP1 may function in a SWI/SNF-independent manner
Mode-Locking in Driven Disordered Systems as a Boundary-Value Problem
We study mode-locking in disordered media as a boundary-value problem.
Focusing on the simplest class of mode-locking models which consists of a
single driven overdamped degree-of-freedom, we develop an analytical method to
obtain the shape of the Arnol'd tongues in the regime of low ac-driving
amplitude or high ac-driving frequency. The method is exact for a scalloped
pinning potential and easily adapted to other pinning potentials. It is
complementary to the analysis based on the well-known Shapiro's argument that
holds in the perturbative regime of large driving amplitudes or low driving
frequency, where the effect of pinning is weak.Comment: 6 pages, 7 figures, RevTeX, Submitte
Peripheral serotonin deficiency affects anxiety-like behavior and the molecular response to an acute challenge in rats
Serotonin is synthetized through the action of tryptophan hydroxylase (TPH) enzymes. While the TPH2 isoform is responsible for the production of serotonin in the brain, TPH1 is expressed in peripheral organs. Interestingly, despite its peripheral localization, alterations of the gene coding for TPH1 have been related to stress sensitivity and an increased susceptibility for psychiatric pathologies. On these bases, we took advantage of newly generated TPH1(-/-)rats, and we evaluated the impact of the lack of peripheral serotonin on the behavior and expression of brain plasticity-related genes under basal conditions and in response to stress. At a behavioral level, TPH1(-/-) rats displayed reduced anxiety-like behavior. Moreover, we found that neuronal activation, quantified by the expression of (Bdnf) and the immediate early gene (Arc) and transcription of glucocorticoid responsive genes after 1 h of acute restraint stress, was blunted in TPH1(-/-) rats in comparison to TPH1 animals(+/+). Overall, we provided evidence for the influence of peripheral serotonin levels in modulating brain functions under basal and dynamic situations
Relativistic Hydrodynamic Evolutions with Black Hole Excision
We present a numerical code designed to study astrophysical phenomena
involving dynamical spacetimes containing black holes in the presence of
relativistic hydrodynamic matter. We present evolutions of the collapse of a
fluid star from the onset of collapse to the settling of the resulting black
hole to a final stationary state. In order to evolve stably after the black
hole forms, we excise a region inside the hole before a singularity is
encountered. This excision region is introduced after the appearance of an
apparent horizon, but while a significant amount of matter remains outside the
hole. We test our code by evolving accurately a vacuum Schwarzschild black
hole, a relativistic Bondi accretion flow onto a black hole, Oppenheimer-Snyder
dust collapse, and the collapse of nonrotating and rotating stars. These
systems are tracked reliably for hundreds of M following excision, where M is
the mass of the black hole. We perform these tests both in axisymmetry and in
full 3+1 dimensions. We then apply our code to study the effect of the stellar
spin parameter J/M^2 on the final outcome of gravitational collapse of rapidly
rotating n = 1 polytropes. We find that a black hole forms only if J/M^2<1, in
agreement with previous simulations. When J/M^2>1, the collapsing star forms a
torus which fragments into nonaxisymmetric clumps, capable of generating
appreciable ``splash'' gravitational radiation.Comment: 17 pages, 14 figures, submitted to PR
Strongly Hyperbolic Extensions of the ADM Hamiltonian
The ADM Hamiltonian formulation of general relativity with prescribed lapse
and shift is a weakly hyperbolic system of partial differential equations. In
general weakly hyperbolic systems are not mathematically well posed. For well
posedness, the theory should be reformulated so that the complete system,
evolution equations plus gauge conditions, is (at least) strongly hyperbolic.
Traditionally, reformulation has been carried out at the level of equations of
motion. This typically destroys the variational and Hamiltonian structures of
the theory. Here I show that one can extend the ADM formalism to (i)
incorporate the gauge conditions as dynamical equations and (ii) affect the
hyperbolicity of the complete system, all while maintaining a Hamiltonian
description. The extended ADM formulation is used to obtain a strongly
hyperbolic Hamiltonian description of Einstein's theory that is generally
covariant under spatial diffeomorphisms and time reparametrizations, and has
physical characteristics. The extended Hamiltonian formulation with 1+log
slicing and gamma--driver shift conditions is weakly hyperbolic.Comment: This version contains minor corrections and clarifications. The
format has been changed to conform with IOP styl
Inflation Physics from the Cosmic Microwave Background and Large Scale Structure
Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of CMB and large-scale structure (LSS) experiments are poised to test the leading paradigm for these earliest moments---the theory of cosmic inflation---and to detect the imprints of the inflationary epoch, thereby dramatically increasing our understanding of fundamental physics and the early universe. A future CMB experiment with sufficient angular resolution and frequency coverage that surveys at least 1 of the sky to a depth of 1 uK-arcmin can deliver a constraint on the tensor-to-scalar ratio that will either result in a 5-sigma measurement of the energy scale of inflation or rule out all large-field inflation models, even in the presence of foregrounds and the gravitational lensing B-mode signal. LSS experiments, particularly spectroscopic surveys such as the Dark Energy Spectroscopic Instrument, will complement the CMB effort by improving current constraints on running of the spectral index by up to a factor of four, improving constraints on curvature by a factor of ten, and providing non-Gaussianity constraints that are competitive with the current CMB bounds
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