574 research outputs found
Sex, Age, and Socioeconomic Differences in Nonfatal Stroke Incidence and Subsequent Major Adverse Outcomes
BACKGROUND AND PURPOSE: Data about variations in stroke incidence and subsequent major adverse outcomes are essential to inform secondary prevention and prioritizing resources to those at the greatest risk of major adverse end points. We aimed to describe the age, sex, and socioeconomic differences in the rates of first nonfatal stroke and subsequent major adverse outcomes. METHODS: The cohort study used linked Clinical Practice Research Datalink and Hospital Episode Statistics data from the United Kingdom. The incidence rate (IR) ratio of first nonfatal stroke and subsequent major adverse outcomes (composite major adverse cardiovascular events, recurrent stroke, cardiovascular disease-related, and all-cause mortality) were calculated and presented by year, sex, age group, and socioeconomic status based on an individual's location of residence, in adults with incident nonfatal stroke diagnosis between 1998 and 2017. RESULTS: A total of 82 774 first nonfatal stroke events were recorded in either primary care or hospital data-an IR of 109.20 per 100 000 person-years (95% CI, 108.46-109.95). Incidence was significantly higher in women compared with men (IR ratio, 1.13 [95% CI, 1.12-1.15]; P<0.001). Rates adjusted for age and sex were higher in the lowest compared with the highest socioeconomic status group (IR ratio, 1.10 [95% CI, 1.08-1.13]; P<0.001). For subsequent major adverse outcomes, the overall incidence for major adverse cardiovascular event was 38.05 per 100 person-years (95% CI, 37.71-38.39) with a slightly higher incidence in women compared with men (38.42 versus 37.62; IR ratio, 1.02 [95% CI, 1.00-1.04]; P=0.0229). Age and socioeconomic status largely accounted for the observed higher incidence of adverse outcomes in women. CONCLUSIONS: In the United Kingdom, incidence of initial stroke and subsequent major adverse outcomes are higher in women, older populations, and people living in socially deprived areas
Optical echo in photonic crystals
The dynamics of photonic wavepacket in the effective oscillator potential is
studied. The oscillator potential is constructed on a base of one dimensional
photonic crystal with a period of unit cell adiabatically varied in space. The
structure has a locally equidistant discrete spectrum. This leads to an echo
effect, i.e. the periodical reconstruction of the packet shape. The effect can
be observed in a nonlinear response of the system. Numerical estimations for
porous-silicon based structures are presented for femtosecond Ti:Sapphire laser
pump.Comment: 4 page
Main directions of the study of plant invasions in Russia
This article is focused on the analysis of major approaches to plant invasion research used by Russian researchers. Multivariate statistical methods allow for the visualization of various data, including those on alien species group structures in various region
Surface Roughness and Effective Stick-Slip Motion
The effect of random surface roughness on hydrodynamics of viscous
incompressible liquid is discussed. Roughness-driven contributions to
hydrodynamic flows, energy dissipation, and friction force are calculated in a
wide range of parameters. When the hydrodynamic decay length (the viscous wave
penetration depth) is larger than the size of random surface inhomogeneities,
it is possible to replace a random rough surface by effective stick-slip
boundary conditions on a flat surface with two constants: the stick-slip length
and the renormalization of viscosity near the boundary. The stick-slip length
and the renormalization coefficient are expressed explicitly via the
correlation function of random surface inhomogeneities. The effective
stick-slip length is always negative signifying the effective slow-down of the
hydrodynamic flows by the rough surface (stick rather than slip motion). A
simple hydrodynamic model is presented as an illustration of these general
hydrodynamic results. The effective boundary parameters are analyzed
numerically for Gaussian, power-law and exponentially decaying correlators with
various indices. The maximum on the frequency dependence of the dissipation
allows one to extract the correlation radius (characteristic size) of the
surface inhomogeneities directly from, for example, experiments with torsional
quartz oscillators.Comment: RevTeX4, 14 pages, 3 figure
Lattice Boltzmann simulations in microfluidics: probing the no-slip boundary condition in hydrophobic, rough, and surface nanobubble laden microchannels
In this contribution we review recent efforts on investigations of the effect
of (apparent) boundary slip by utilizing lattice Boltzmann simulations. We
demonstrate the applicability of the method to treat fundamental questions in
microfluidics by investigating fluid flow in hydrophobic and rough
microchannels as well as over surfaces covered by nano- or microscale gas
bubbles.Comment: 11 pages, 6 figure
Crosstalk between Mitochondrial and Sarcoplasmic Reticulum Ca2+ Cycling Modulates Cardiac Pacemaker Cell Automaticity
Mitochondria dynamically buffer cytosolic Ca(2+) in cardiac ventricular cells and this affects the Ca(2+) load of the sarcoplasmic reticulum (SR). In sinoatrial-node cells (SANC) the SR generates periodic local, subsarcolemmal Ca(2+) releases (LCRs) that depend upon the SR load and are involved in SANC automaticity: LCRs activate an inward Na(+)-Ca(2+) exchange current to accelerate the diastolic depolarization, prompting the ensemble of surface membrane ion channels to generate the next action potential (AP).To determine if mitochondrial Ca(2+) (Ca(2+) (m)), cytosolic Ca(2+) (Ca(2+) (c))-SR-Ca(2+) crosstalk occurs in single rabbit SANC, and how this may relate to SANC normal automaticity.Inhibition of mitochondrial Ca(2+) influx into (Ru360) or Ca(2+) efflux from (CGP-37157) decreased [Ca(2+)](m) to 80 ± 8% control or increased [Ca(2+)](m) to 119 ± 7% control, respectively. Concurrent with inhibition of mitochondrial Ca(2+) influx or efflux, the SR Ca(2+) load, and LCR size, duration, amplitude and period (imaged via confocal linescan) significantly increased or decreased, respectively. Changes in total ensemble LCR Ca(2+) signal were highly correlated with the change in the SR Ca(2+) load (r(2) = 0.97). Changes in the spontaneous AP cycle length (Ru360, 111 ± 1% control; CGP-37157, 89 ± 2% control) in response to changes in [Ca(2+)](m) were predicted by concurrent changes in LCR period (r(2) = 0.84).A change in SANC Ca(2+) (m) flux translates into a change in the AP firing rate by effecting changes in Ca(2+) (c) and SR Ca(2+) loading, which affects the characteristics of spontaneous SR Ca(2+) release
Plant invasion research in Russia: basic projects and scientific fields
This paper represents a review of comprehensive research into invasion biology done by Russian scholars for four decades. Invasion biology is a relatively new field of research focused on the study of alien plants, their behavior in new habitats and risks they pose to indigenous species. It is shown that over 40 years, single finds of alien plant species have transformed into a check-list of invasive species in Russi
Initial stage of formation of spontaneous invasive populations of garden lupine (lupinus polyphyllus lindl.) at the northern limit of its secondary distribution range in the veps forest nature park
A weed plant of the species Lupinus polyphyllus was found in settlements located on the territory of the natural park «Vepssky forest» of the Leningrad regio
Immunoglobulinopathies in patients with angioimmunoblastic T-cell lymphoma
Contex. Angioimmunoblastic T-cell lymphoma (AITL) is a rare form of non-Hodgkins lymphoma, characterized by generalized lymphadenopathy, hepatosplenomegaly and dysproteinemia. Hypergammaglobulinaemia is revealed in 50-83% pts with AITL. However, the characteristics of immunoglobulinopathies observed in AITL are scarce. Objective: The aim of the study was to characterize quantitative and qualitative immunoglobulinopathies in patients with AITL at the onset of the disease. Patients and methods. 55 patients with newly diagnosed AITL were enrolled in the study, the male/female ratio was 30/25; median age was 61 (29-81) years. Diagnosis was based on standard WHO criteria. Immunochemical studies of blood serum included serum protein electrophoresis/immunofixation, nephelometric quantification of total immunoglobulins, serum free light chain assay. Results. Quantitative and qualitative immunoglobulinopathies were determined in 49 (89,1%) of 55 pts. Quantitative immunoglobulinopathies were revealed in 47 (85.5%) of 55 cases, qualitative - in 14 (25,5%). Combination quantitative and qualitative immunoglobulinopathies was observed in 12 (21,8%) of 55 pts. The detected immunoglobulinopathies were divided into 4 groups: polyclonal hypergammaglobulinaemia, hypogammaglobulinaemia, oligoclonal gammapathy, and monoclonal gammapathy. Polyclonal hypergammaglobulinaemia was marked in 41 (74.5%) of 55 pts, elevated level of IgG was determined in 27 (49,15%) of 55 cases, IgM - in 18 (32,7%) and IgA - in 21 (38.2%). Interestingly, polyclonal IgE hypergammaglobulinaemia was detected in 12 (48,0%) of 25 cases of performed studies. Hypogammaglobulinaemia was detected in 8 (14,5%) of 55 cases. Oligoclonal gammapathy was determined in 4 (7.3%) of 55 pts. Monoclonal gammapathy was revealed in 11 (20,0%) of 55 cases. The amount of monoclonal immunoglobulin varied from 2.6 to 14.1 g/l. Monoclonal immunoglobulin Gk was detected in 5 of 11 pts, Gλ - in 2, Mλ - in 2, Mk - in 2. Monoclonal gammapathy was accompanied by polyclonal hypergammaglobulinaemia in 9 of 11 cases, hypogammaglobulinaemia - in 2. Conclusions. Quantitative and qualitative immunoglobulinopathies are observed in most patients at the onset of AITL. Quantitative abnormalities were determined more often than qualitative. Monoclonal gammapathy can be a manifestation of lymphoproliferation and other concomitant disorders. The prognostic value of immunochemical parameters is still unclear and requires dynamic observation and study
A Dissipative-Particle-Dynamics Model for Simulating Dynamics of Charged Colloid
A mesoscopic colloid model is developed in which a spherical colloid is
represented by many interacting sites on its surface. The hydrodynamic
interactions with thermal fluctuations are taken accounts in full using
Dissipative Particle Dynamics, and the electrostatic interactions are simulated
using Particle-Particle-Particle Mesh method. This new model is applied to
investigate the electrophoretic mobility of a charged colloid under an external
electric field, and the influence of salt concentration and colloid charge are
systematically studied. The simulation results show good agreement with
predictions from the electrokinetic theory.Comment: 17 pages, 8 figures, submitted to the proceedings of High Performance
Computing in Science & Engineering '1
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