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Modeling laser-induced incandescence of soot: a summary and comparison of LII models

We have performed a comparison of ten models that predict the temporal behavior of laser-induced incandescence (LII) of soot. In this paper we present a summary of the models and comparisons of calculated temperatures, diameters, signals, and energy-balance terms. The models were run assuming laser heating at 532 nm at fluences of 0.05 and 0.70 J/cm(2) with a laser temporal profile provided. Calcu

Model-free arterial spin labelling for cerebral blood flow quantification: introduction of regional arterial input functions identified by factor analysis.

PURPOSE: To identify regional arterial input functions (AIFs) using factor analysis of dynamic studies (FADS) when quantification of perfusion is performed using model-free arterial spin labelling. MATERIAL AND METHODS: Five healthy volunteers and one patient were examined on a 3-T Philips unit using quantitative STAR labelling of arterial regions (QUASAR). Two sets of images were retrieved, one w

Habermas on Foucault. Critical remarks

The relation between the œuvres of Jurgen Habermas and Michel Foucault constitutes an important reference point to several aspects of contemporary social research and philosophical discussion. In this paper I give an account of Habermas's critique of Foucault, a critique which operates on three levels-methodology, empirical descriptions, and political implications. I also make some commentaries on

Upregulation of p75 neurotrophin receptor after stroke in mice does not contribute to differential vulnerability of striatal neurons

The survival of different neuron types and the expression of the p75 neurotrophin receptor (p75(NTR)) after focal cerebral ischemia were studied in the mouse striatum using immunocytochemical and histochemical techniques and stereological procedures. As assessed at 1 week after 30 min of middle cerebral artery occlusion, the order of vulnerability was projection neurons > parvalbumin-expressing in

Vascular Endothelial Growth Factor in Central Nervous System Injuries - A Vascular Growth Factor Getting Nervous?

Vascular Endothelial Growth Factor ( VEGF) is recognized as a central factor in growth, survival and permeability of blood vessels in both physiological and pathological conditions. It is as such of importance for vascular responses in various central nervous system (CNS) disorders. Accumulating evidence suggest that VEGF may also act as a neuroprotective and neurotrophic factor supporting neurona

Parametric study and multiple correlations on air-side heat transfer and friction characteristics of fin-and-tube heat exchangers with large number of large-diameter tube rows

In the present study, for industrial applications of large inter-coolers employed in multi-stage compressor systems the air-side laminar heat transfer and fluid flow characteristics of plain fin-and-tube heat exchangers with large number of tube rows and large diameter of the tubes arc investigated numerically through three-dimensional simulations based on the SIMPLE algorithm in Cartesian coordin

Velocities for moving random surfaces

For a stationary two-dimensional random field evolving in time, we derive statistical distributions of appropriately defined velocities. The results are based on a generalization of the Rice formula. We discuss importance of identifying the correct form of the distribution which accounts for the sampling bias. The theory can be applied to practical problems where evolving random fields are conside

Molecularly imprinted polymer for analysis of trace atrazine herbicide in water

A molecularly imprinted polymer (MIP) for atrazine was synthesized by non-covalent method. The binding capacity of MIP was 1.00 mg g(-1) polymer. The selectivity and recovery were investigated with various pesticides which are mostly, found in the environment, for both similar and different chemical structure of atrazine. The competitive recognition between atrazine and structurally similar compou

Coagulation and anticoagulation effects of contraceptive steroids

PIP: The first generation high-dose ( 80 mcg estrogen) oral contraceptives (OCs) were associated with an increased risk of deep venous thrombosis (DVT). So manufacturers removed the high-dose OCs and first replaced them with OCs with 50 mcg estrogen, resulting in a lower incidence of thromboembolic events (40 vs. 20/100,000 users). When they introduced an even lower dose OC (30 mcg estrogen), the

Molecular analysis of a Saccharomyces cerevisiae mutant with improved ability to utilize xylose shows enhanced expression of proteins involved in transport, initial xylose metabolism, and the pentose phosphate pathway.

Differences between the recombinant xylose-utilizing Saccharomyces cerevisiae strain TMB 3399 and the mutant strain TMB 3400, derived from TMB 3399 and displaying improved ability to utilize xylose, were investigated by using genome-wide expression analysis, physiological characterization, and biochemical assays. Samples for analysis were withdrawn from chemostat cultures. The characteristics of S

COPD and co-morbidities, with special emphasis on cardiovascular conditions

The concept of COPD as a systemic disease has been widely accepted in the past several years. In parallel, it has been emphasised that COPD morbidity and mortality is strongly related to co-morbid conditions. This review summarises some recent studies showing that in patients with COPID, the prevalence of cardiac failure is manifested in 10%-46% of the patients, and that up to 40% of patients with

Ag@SiO2 Core-Shell Nanoparticles for Probing Spatial Distribution of Electromagnetic Field Enhancement via Surface-Enhanced Raman Scattering

We show that the spatial distribution of the electromagnetic (EM) field enhancement can be probed directly via dynamic evolution of surface-enhanced Raman scattering (SERS) of rhodamine 6G (R6G) molecules as they diffuse into Ag@SiO2 core-shell nanoparticles. The porous silica shell limits the diffusion of R6G molecules toward Inner Ag cores, thereby allowing direct observation and quantification

NMR structure determination of proteins supplemented by quantum chemical calculations: Detailed structure of the Ca2+ sites in the EGF34 fragment of protein S

We present and test two methods to use quantum chemical calculations to improve standard protein structure refinement by molecular dynamics simulations restrained to experimental NMR data. In the first, we replace the molecular mechanics force field ( employed in standard refinement to supplement experimental data) for a site of interest by quantum chemical calculations. This way, we obtain an acc

Fluid-present melting of meta-igneous rocks and the generation of leucogranites - Constraints from garnet major- and trace element data, Lu-Hf whole rock-garnet ages and whole rock Nd-Sr-Hf-O isotope data

Pan-African high-grade metamorphism in the Proterozoic Damara orogen (Namibia) led to formation of garnet-bearing leucosomes in potassic meta-igneous gneisses producing a meta-igneous migmatite. In addition, the migmatite (gneiss (mesosome) plus leucosome) was intruded by small-scale leucogranitic melts with a high amount of accumulated biotite and garnet. U-Pb zircon ages obtained on the mesosome

Investigation of turbulence models applied to premixed combustion using a level-set flamelet library approach

Most of the common modeling approaches to premixed combustion in engineering applications are either based on the assumption of infinitely fast chemistry or the flamelet assumption with simple chemistry. The level-set flamelet library approach (FLA) has shown great potential in predicting major species and heat release, as well as intermediate and minor species, where more simple models often fail

Atrial myocardial pathoelectrophysiology in adults with a secundum atrial septal defect is unaffected by closure of the defect. A study using high resolution signal-averaged orthogonal P-wave technique.

BACKGROUND: In patients with atrial septal defect (ASD) the P-wave is prolonged as a marker of delayed atrial conduction which is associated with atrial fibrillation. The study aim was to analyse the impact of ASD closure in adults on P-wave duration and morphology by means of signal-averaged P-waves (PSA-ECG) and to investigate potential mechano-electrical interactions. METHODS: PSA-ECG was obtai

Exercise training meta-analysis of trials in patients with chronic heart failure (ExTraMATCH)

Objective To determine the effect of exercise training on survival in patients with heart failure due to left ventricular systolic dysfunction. Design Collaborative meta-analysis. Inclusion criteria Randomised parallel group controlled trials of exercise training, for at least eight weeks with individual patient data on survival for at least three months. Studies reviewed Nine datasets, totalling