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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

Granulocytic sarcomas in body cavities in childhood acute myeloid leukemias with 11q23/MLL rearrangements

Three childhood acute monoblastic leukemias (AML M5) with granulocytic sarcomas (GSs) are described. All displayed 11q23/MLL abnormalities, t(9;11)(p22;q23) in two cases and t(11;17)(q23;q21) in one case, constituting around 20% of all 11q23-positive AML cytogenetically investigated in our department. Two of the patients had GS in multiple locations, and all three had abdominal GS. In two of them,

A negative trend of biomedical research in Libya: a bibliometric study

Background: It is well established that Libya is lagging behind its peers in biomedical research. The aim of this study is to analyse all the original biomedical publications affiliated with Libya from 1973 to 2007. Methods: PubMed and the Science Citation Index Expanded were searched for 'original research' biomedical studies affiliated with Libya. The generated data were hand searched and 329 'o

Transcriptome analysis in a rat model of L-DOPA-induced dyskinesia

We have examined the pattern of striatal messenger RNA expression of over 8000 genes in a rat model of levodopa (L-DOPA)-induced dyskinesia and Parkinson disease (PD). 6-Hydroxydopamine (6-OHDA)-lesioned rats were treated with L-DOPA or physiological saline for 22 days and repeatedly tested for antiakinetic response to L-DOPA and the development of abnormal involuntary movements (AIMs). In a compa

Immunohistochemical study of 158 lung carcinomas

Lung carcinomas were studied immunohistochemically and the results were related to type of tissue sample (bronchoscopic biopsies, surgical specimens, autopsies). All cytokeratins (CAM 5.2, PKK-1, AE1/AE3) reacted with virtually all adenocarcinomas, most squamous, and 65% of the large cell carcinomas, while CAM 5.2 was most efficient with the small cell carcinomas. CEA stained 33% and 60% of the sm

Metabolism of high density lipoproteins in liver cancer

Liver plays a vital role in the production and catabolism of plasma lipoproteins. It depends on the integrity of cellular function of liver, which ensures homeostasis of lipid and lipoprotein metabolism. When liver cancer occurs these processes are impaired and high-density lipoproteins are changed. (C) 2007 The WJG Press. All rights reserved.

All-optical cw quadruple resonance excitation: A coherently driven five-level molecular system

We report here a continuous-wave, high-resolution, and all-optical quadruple resonance laser excitation experiment. To demonstrate this excitation technique, we have used an inhomogeneously broadened molecular sample (Na-2). We emphasize the enhanced ability afforded by the technique to reach new ranges of internuclear separation as well as access to a large range of molecular electronic states. U

Tritrophic interactions in a soil community enhance decomposition rates

Microbivorous soil fauna can influence decomposition rates by regulating biomass and composition of the microbial community. The idea that predators at higher trophic levels regulate population densities of microbivorous fauna and thus indirectly increase microbial growth and activity has often been suggested but rarely examined in soil ecosystems. In this paper the effects of tritrophic interacti

A homologous genetic basis of the murine cpfl1 mutant and human achromatopsia linked to mutations in the PDE6C gene

Retinal cone photoreceptors mediate fine visual acuity, daylight vision, and color vision. Congenital hereditary conditions in which there is a lack of cone function in humans cause achromatopsia, an autosomal recessive trait, characterized by low vision, photophobia, and lack of color discrimination. Herein we report the identification of mutations in the PDE6C gene encoding the catalytic subunit

Simulation of phase equilibria in lamellar surfactant systems

The coexistence of two lamellar liquid crystalline phases has been investigated by means of Monte Carlo simulations. The surfaces of the negatively charged bilayers formed by the surfactant molecules are modeled as planar infinite walls with a uniform surface charge density. Water is treated as a dielectric continuum, and only electrostatic interactions are considered. The counterions are mono- an

Learning From Organizational Incidents: Resilience Engineering for High-Risk Process Environments

For years, safety improvements have been made by evaluating incident reports and analyzing errors and violations. Current developments in safety science, however, challenge the idea that safety can meaning-fully be be seen as the absence of errors or other negatives. Instead, the question becomes whether a company is aware of positive ways in which people, at all level of the organisation, contrib

Prevention of arthropathy: may it be extrapolated from patients without inhibitors to patients with inhibitors?

Although no consensus on the exact dosing schedule of prophylaxis in non-inhibitor haemophilia patients has been achieved, regular administration of factor VIII (FVIII) or factor IX (FIX) concentrates is currently accepted as the most effective treatment model in order to prevent sick days, hospital stays and the development of arthropathy in patients with severe haemophilia. The basis for prophyl

Clinicopathologic re-evaluation of 100 malignant fibrous histiocytomas: prognostic relevance of subclassification

PURPOSE: Malignant fibrous histiocytoma (MFH) has been regarded as the most common soft tissue sarcoma (STS) in adults. Yet its true nature and the validity of this diagnostic concept have increasingly been questioned. Available data suggest that most patients with MFH can be subclassified into specific STS types, but the clinical relevance of such categorization has been argued. In a retrospectiv

Nanoscale tungsten aerosol particles embedded in GaAs

GaAs containing buried nanoscale tungsten particles has been characterized electrically. The particles were produced using a special aerosol process and were embedded in GaAs by epitaxial overgrowth. Two different particle sizes were investigated separately. When the particle concentration was increased, a conductance drop of about 500 times was observed. A simulation model, based on a random dist

Controlled Step Growth of Molecularly Linked Gold Nanoparticles: From Metallic Monomers to Dimers to Polymeric Nanoparticle Chains.

The solution-phase assembly of 15 nm gold particles into relatively linear chains of fairly controllable length of up to 1 mum is achieved by molecularly linking nanoparticles with alkanedithiols. This step-growth process can be controlled to prepare dimers, oligomers, and polymer-like gold nanoparticle chains by varying the ratio of alkanedithiols to nanoparticles. These size-controlled, relative