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Quantum dot photodegradation due to CdSe-ZnO charge transfer: Transient absorption study

We study changes in ultrafast transient absorption due to photodegradation of quantum dots attached to ZnO nanowire. The time-resolved measurements reveal impact of photodegradation on three distinct kinetic components present in transient absorption tau similar to 7 ps, 80 ps, and 7.5 ns). In addition, we observe superlinear dependence of photodegradation rate on concentration of excited electron

Evidence for ligand hydrolysis and Fe(III) reduction in the dissolution of goethite by desferrioxamine-B

Desferrioxamine-B (DFOB) is a bacterial trihydroxamate siderophore and probably the most studied to date. However, the manner in which DFOB adsorbs at mineral surfaces and promotes dissolution is still under discussion. Here we investigated the adsorption and dissolution reactions in the goethite-DFOB system using both in situ infrared spectroscopic and quantitative analytical methods. Experiments

Elevated plasma levels of heparin-binding protein in intensive care unit patients with severe sepsis and septic shock

Introduction: Rapid detection of, and optimized treatment for, severe sepsis and septic shock is crucial for successful outcome. Heparin-binding protein (HBP), a potent inducer of increased vascular permeability, is a potentially useful biomarker for predicting outcome in patients with severe infections. Our aim was to study the systemic release and dynamics of HBP in the plasma of patients with s

Heat-induced aggregation of thylakoid membranes affect their interfacial properties.

Many of our most popular lipid containing foods are in emulsion form. These foods are often highly palatable with high caloric density, that subsequently increases the risk of overconsumption and possibly lead to obesity. Regulating the lipid bioavailability of high-fat foods is one approach to prevent overconsumption. Thylakoids, the chloroplast membrane, creates a barrier around lipid droplets,

Batch-Specific Discrimination Using Nuclear Quadrupole Resonance Spectroscopy

In this paper, we report on the identification of batches of analgesic paracetamol (acetaminophen) tablets using nitrogen-14 nuclear quadrupole resonance spectroscopy (N-14 NQR). The high sensitivity of NQR to the electron charge distribution surrounding the quadrupolar nucleus enables the unique characterization of the crystal structure of the material. Two hypothesis were tested on batches of th

Determination of Nicotine Absorption from Multiple Tobacco Products and Nicotine Gum

Snus is a smokeless tobacco product traditionally used in Scandinavia and available in pouched or loose forms. The objective of this study was to determine nicotine absorption for current pouched and loose snus products in comparison with a cigarette and an over-the-counter nicotine gum. We conducted an open-label, randomized, 6-way, crossover study involving 20 healthy snus and cigarette users. O

A Combinatorial Approach to $L_1$-Matrix Factorization

Recent work on low-rank matrix factorization has focused on the missing data problem and robustness to outliers and therefore the problem has often been studied under the $L_1$-norm. However, due to the non-convexity of the problem, most algorithms are sensitive to initialization and tend to get stuck in a local optimum. In this paper, we present a new theoretical framework aimed at achieving opt

The Geography and Structure of Global Innovation Networks: A Knowledge Base Perspective

This paper explores the geography and structure of global innovation networks (GINs) of two multinational companies belonging to industries with different knowledge bases. It contributes to the existing literature on knowledge bases, by studying both intra-firm and inter-firm GINs. By means of social network analysis based on primary data, we identify two different forms of GINs, namely the global

Plasma fetuin-A concentration, genetic variation in the AHSG gene and risk of colorectal cancer

Fetuin-A, also referred to as alpha 2-Heremans-Schmid glycoprotein (AHSG), is a liver protein known to inhibit insulin actions. Hyperinsulinemia is a possible risk factor for colorectal cancer; however, the role of fetuin-A in the development of colorectal cancer is unclear. We investigated the association between circulating fetuin-A and colorectal cancer risk in a nested case-control study withi

Small-angle X-ray Scattering Study of a Rex Family Repressor: Conformational Response to NADH and NAD(+) Binding in Solution.

The transcriptional repressor Rex is a sensor of the intracellular NADH/NAD(+) redox state through direct binding of NADH or NAD(+). Homodimeric Rex protein from Thermus aquaticus (T-Rex) and Bacillus subtilis (B-Rex) exists in several different conformations. In both organisms, Rex in complex with NADH has the DNA binding domains packed together at the dimer interface, whereas in the apo form of

Kinin-Stimulated B1 Receptor Signaling Depends on Receptor Endocytosis Whereas B2 Receptor Signaling Does Not.

Kinins are potent pro-inflammatory peptides that act through two G protein-coupled receptor subtypes, B1 (B1R) and B2 (B2R). Kinin-stimulated B2R signaling is often transient, whereas B1R signaling is sustained. This was confirmed by monitoring agonist-stimulated intracellular Ca(2+) mobilization in A10 smooth muscle cells expressing human wild-type B2R and B1R. We further studied the role of rece

TFPI cofactor function of protein S: essential role of the protein S SHBG-like domain

Protein S is a cofactor for tissue factor pathway inhibitor (TFPI), accelerating the inhibition of activated factor X (FXa). TFPI Kunitz domain 3 residue Glu226 is essential for enhancement of TFPI by protein S. To investigate the complementary functional interaction site on protein S, we screened 44 protein S point, composite or domain swap variants spanning the whole protein S molecule for their

Spontaneous activity and stretch-induced contractile differentiation are reduced in vascular smooth muscle of miR-143/145 knockout mice.

Stretch is essential for maintaining the contractile phenotype of vascular smooth muscle cells, and small non-coding microRNAs are known to be important in this process. Using a Dicer knockout model, we have previously reported that microRNAs are essential for stretch-induced differentiation and regulation of L-type calcium channel expression. The aim of this study was to investigate the importanc

A method for measuring the imbibation rate of powder in a liquid

Mixing of powders into liquids is a common unit operation. Mixing can be divided into several steps: imbibation of the powder into the liquid being the first Under some circumstances, for instance, if the powder has poor wetting properties, imbibation can be the rate-determining step. In this study imbibation in a commercial mixer was studied and a method to measure powder imbibation in a model th

Estimation of daily evapotranspiration over Africa using MODIS/Terra and SEVIRI/MSG data

Most existing remote sensing-based evapotranspiration (ET) algorithms rely exclusively on polar-orbiting satellites with thermal infrared sensors, and therefore the resulting ET values represent only "instantaneous or snapshot" values. However, daily ET is more meaningful and useful in applications. In this study, daily ET estimates are obtained by combining data from the MODIS sensor aboard the p

Intra- and inter-observer reproducibility of assessment of Doppler ultrasound findings in adnexal masses.

Objectives: To estimate intra- and inter-observer reproducibility and reliability of assessment of the color content in adnexal masses at color/power Doppler ultrasound examination for observers with different levels of experience, and to determine if they change after a consensus meeting. Methods: Digital clips with color/power Doppler information of 103 adnexal masses were evaluated independentl

Development of a compact multipass oxygen sensor used for gas diffusion studies in opaque media

A highly scattering porous ceramic sample is employed as a miniature random-scattering multipass gas cell for monitoring of oxygen content in opaque media, that is, wood materials in the present work. Gas in scattering media absorption spectroscopy is used by employing a 760 nm near-infrared laser diode to probe the absorption of molecular oxygen enclosed in the pores of the ceramic material worki

Genetic analysis implicates APOE, SNCA and suggests lysosomal dysfunction in the etiology of Dementia with Lewy Bodies.

Clinical and neuropathological similarities between Dementia with Lewy Bodies (DLB), ParkinsonÕs and AlzheimerÕs diseases (PD and AD, respectively) suggest that these disorders may share etiology. To test this hypothesis we have performed an association study of 54 genomic regions, previously implicated in PD or AD, in a large cohort of DLB cases and controls. The cohort comprised 788 DLB cases an