Search results for "SWI"

Spatial learning and expression patterns of PP1 mRNA in mouse hippocampus.

2009

<i>Background:</i> Synaptic plasticity is believed to be the major cellular basis for learning and memory. Protein phosphorylation is a key process involved in changes in the efficacy of neurotransmission. In long-term changes synaptic plasticity is followed by structural plasticity and protein de novo synthesis. Such mechanisms are believed to build the basis of hippocampal learning and memory investigated in the Morris water maze (MWM) task. To examine the role of dephosphorylation during that model for spatial learning, we analyzed protein phosphatase 1 (PP1) expression in the hippocampus of mice at various stages of the task and in two groups with different learning abilitie…

Influence of respiratory rate and end-expiratory pressure variation on cyclic alveolar recruitment in an experimental lung injury model

2012

Introduction Cyclic alveolar recruitment/derecruitment (R/D) is an important mechanism of ventilator-associated lung injury. In experimental models this process can be measured with high temporal resolution by detection of respiratory-dependent oscillations of the paO2 (ΔpaO2). A previous study showed that end-expiratory collapse can be prevented by an increased respiratory rate in saline-lavaged rabbits. The current study compares the effects of increased positive end-expiratory pressure (PEEP) versus an individually titrated respiratory rate (RRind) on intra-tidal amplitude of Δ paO2 and on average paO2 in saline-lavaged pigs. Methods Acute lung injury was induced by bronchoalveolar lavag…

Respiratory mechanics measured by forced oscillations during mechanical ventilation through a tracheal tube

2011

The forced oscillation technique (FOT) allows the measurement of respiratory mechanics in the intensive care setting. The aim of this study was to compare the FOT with a reference method during mechanical ventilation through a tracheal tube. The respiratory impedance spectra were measured by FOT in nine anaesthetized pigs, and resistance and compliance were estimated on the basis of a linear resistance-compliance inertance model. In comparison, resistance and compliance were quantified by the multiple linear regression analysis (LSF) of conventional ventilator waveforms to the equation of motion. The resistance of the sample was found to range from 6 to 21 cmH(2)O s l(-1) and the compliance…

Nucleosome-specific, Time-dependent Changes in Histone Modifications during Activation of the Early Growth Response 1 (Egr1) Gene

2014

Histone post-translational modifications and nucleosome remodeling are coordinate events involved in eukaryotic transcriptional regulation. There are relatively few data on the time course with which these events occur in individual nucleosomes. As a contribution to fill this gap, we first describe the nature and time course of structural changes in the nucleosomes -2, -1, and +1 of the murine Egr1 gene upon induction. To initiate the transient activation of the gene, we used the stimulation of MLP29 cells with phorbol esters and the in vivo activation after partial hepatectomy. In both models, nucleosomes -1 and +1 are partially evicted, whereas nucleosomes +1 and -2 slide downstream durin…

Notice of Violation of IEEE Publication Principles: Robust Delay-Dependent $H_{\infty}$ Control of Uncertain Time-Delay Systems With Mixed Neutral, D…

2011

The problem of robust mode-dependent delayed state feedback H∞ control is investigated for a class of uncertain time-delay systems with Markovian switching parameters and mixed discrete, neutral, and distributed delays. Based on the Lyapunov-Krasovskii functional theory, new required sufficient conditions are established in terms of delay-dependent linear matrix inequalities for the stochastic stability and stabilization of the considered system using some free matrices. The desired control is derived based on a convex optimization method such that the resulting closed-loop system is stochastically stable and satisfies a prescribed level of H∞ performance, simultaneously. Finally, two numer…

Biodegradation of differently cross-linked collagen membranes: an experimental study in the rat.

2005

Contains fulltext : 47774.pdf (Publisher’s version ) (Closed access) The aim of the present study was to compare the biodegradation of differently cross-linked collagen membranes in rats. Five commercially available and three experimental membranes (VN) were included: (1) BioGide (BG) (non-cross-linked porcine type I and III collagens), (2) BioMend (BM), (3) BioMendExtend (BME) (glutaraldehyde cross-linked bovine type I collagen), (4) Ossix (OS) (enzymatic-cross-linked bovine type I collagen), (5) TutoDent (TD) (non-cross-linked bovine type I collagen, and (6-8) VN(1-3) (chemical cross-linked porcine type I and III collagens). Specimens were randomly allocated in unconnected subcutaneous po…

Forming-Free and Self-Rectifying Resistive Switching Effect in Anodic Titanium Dioxide-Based Memristors

2018

The paper presents the resistive switching of electroforming-free Ti/anodic- TiO 2 /Cu memristors. Anodic TiO 2 thin films were prepared by anodizing Ti layers. Microscale devices were fabricated by direct laser-assisted photolithography. Experimental results showed a bipolar and self-rectifying behavior of the devices, which could be useful for crossbar array configurations. Moreover, a gradual resistive switching of the devices in both directions was observed, indicating the presence of multi-level resistance states.

Control of ultra-high switching frequency power converters using virtual flux-based direct power control

2017

This paper presents a control technique for ultra-high switching frequency rectifiers known as virtual flux-based direct power control (VF-DPC). This method utilizes AC voltage sensors to provide better power quality at the input and output of power converters. Performance of an ultra-high switching frequency converter using the extended and conventional VF-DPC method is analyzed. The analysis has shown that the extended VF-DPC method can reduce better the total harmonic distortion (THD) of input currents and the ripples of the output DC voltage as compared to conventional VF-DPC. Finally, the effect of switching frequency and inductance size on rectifier operation is investigated in this s…

Efficient thermo-optically controlled Mach-Zhender interferometers using dielectric-loaded plasmonic waveguides

2012

Compact fiber-coupled dielectric-loaded plasmonic Mach-Zehnder interferometers operating at telecom wavelengths and controlled via the thermo-optic effect are reported. Two fabricated structures with Cytop substrate and a ridge made of PMMA or a cycloaliphatic acrylate polymer (CAP) were considered showing low switching power of 2.35 mW and switching time in the range of microseconds for a CAP ridge and milliseconds switching time for a PMMA ridge. Full output modulation is demonstrated for the structure with a CAP ridge and 40% modulation with a PMMA ridge. (C) 2012 Optical Society of America Compact fiber-coupled dielectric-loaded plasmonic Mach-Zehnder interferometers operating at teleco…

Noisy dynamics in long and short Josephson junctions

The study of nonlinear dynamics in long Josephson junctions and the features of a particular kind of junction realized using a graphene layer, are the main topics of this research work. The superconducting state of a Josephson junction is a metastable state, and the switching to the resistive state is directly related to characteristic macroscopic quantities, such as the current the voltage across the junction, and the magnetic field through it. Noise sources can affect the mean lifetime of this superconducting metastable state, so that noise induced effects on the transient dynamics of these systems should be taken into account. The long Josephson junctions are investigated in the sine-Gor…