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First Direct Study of the Ammonolysis Reaction in the Most Common Alkaline and Alkaline Earth Metal Hydrides by in Situ SR-PXD

We report on the first in situ synchrotron radiation powder X-ray diffraction study (SR-PXD) of the ammonolysis reaction of selected alkaline and alkaline earth metal hydrides (i.e., LiH, NaH, KH, MgH2, and CaH2). The investigation was performed using an in situ SR-PXD pressure cell at an initial NH3 pressure of 6.5 bar in a range of temperature between room temperature (RT) and 350 degrees C. The

Immobilization of Clostridium acetobutylicum DSM 792 as macroporous aggregates through cryogelation for butanol production

In this study, a new cell immobilization technique is presented. Cells of Clostridium acetobutylicum DSM 792 form a macroporous aggregate through cryogelation with concomitant crosslinking together with activated polyethyleneimine (PEI) and poly(vinyl alcohol) (PVA). The cell based cryogel presents a highly porous, elastic structure with walls consisting of densely packed crosslinked cells. The im

The presence of rheumatoid nodules at early rheumatoid arthritis diagnosis is a sign of extra-articular disease and predicts radiographic progression of joint destruction over 5 years

Objective: Radiographic damage is an important outcome in rheumatoid arthritis (RA). The disease course varies considerably, and there is a need for simple and reliable prognostic markers. The aim of the study was to determine the utility of early signs of extra-articular disease, manifested as rheumatoid nodules (RN), in predicting radiographic outcome. Methods: In a cohort (n = 1589) of consecut

Measurement of the production cross section for Z/gamma* in association with jets in pp collisions at root s=7 TeV with the ATLAS detector

Results are presented on the production of jets of particles in association with a Z/gamma* boson, in proton-proton collisions at root s = 7 TeV with the ATLAS detector. The analysis includes the full 2010 data set, collected with a low rate of multiple proton-proton collisions in the accelerator, corresponding to an integrated luminosity of 36 pb(-1). Inclusive jet cross sections in Z/gamma* even

Endogenous androgens and risk of epithelial invasive ovarian cancer by tumor characteristics in the European Prospective Investigation into Cancer and Nutrition

The role of endogenous androgens and sex hormone-binding globulin (SHBG) in ovarian carcinogenesis is poorly understood. Epithelial invasive ovarian cancer (EOC) is a heterogeneous disease and there are no prospective data on endogenous androgens and EOC risk by tumor characteristics (histology, grade, stage) or the dualistic model of ovarian carcinogenesis (i.e. type I vs. type II, leading to les

A hydrogeological study of the Nhandugue River, Mozambique – A major groundwater recharge zone

The Nhandugue River flows over the western margin of the Urema Rift, the southernmost extension of the East African Rift System, and marks the north-western border of Gorongosa National Park, Mozambique. It constitutes one of the major indispensable water resources for the ecosystem that the park protects. Our study focused on the hydrogeological conditions at the western rift margin by resistivit

Factors influencing subjective quality of life in patients with schizophrenia and other mental disorders: A pooled analysis

Subjective quality of life (SQOL) is an important outcome in the treatment of patients with schizophrenia. However, there is only limited evidence on factors influencing SQOL, and little is known about whether the same factors influence SQOL in patients with schizophrenia and other mental disorders. This study aimed to identify the factors associated with SQOL and test whether these factors are eq

Reactive synthesis and characterization of titanium aluminides produced from elemental powder mixtures

The formation of titanium aluminides in Ti–Al elemental powder mixtures containing 25, 50 and 75 at.% Al, has been studied using differential scanning calorimetry (DSC). Phase evolution in the mixture was followed by heating the compacted samples up to 1273 K at 7.5 and 15 K min−1. The cooled samples were characterized using X-ray diffraction, scanning electron microscopy and energy-dispersive spe

Simultaneous Creation and Recovery of Trap States on Quantum Dots in a Photoirradiated CdSe-ZnO System

We study changes in the steady-state absorption and ultrafast transient absorption kinetics of the photoirradiated CdSe quantum dotZnO system. The changes enable us to reconstruct kinetics of trap creation, which are analyzed with respect to three possible models: trap creation without recovery, trap creation and recovery, and trap creation with an upper limit for trap number accommodated on a qua

Exponential Time Complexity of the Permanent and the Tutte Polynomial

We show conditional lower bounds for well-studied #P-hard problems: -The number of satisfying assignments of a 2-CNF formula with n variables cannot be computed in time exp(o(n)), and the same is true for computing the number of all independent sets in an n-vertex graph. -The permanent of an n x n matrix with entries 0 and 1 cannot be computed in time exp(o(n)). -The Tutte polynomial of an n-verte

Novel combined fluorescence/reflectance spectroscopy system for guiding brain tumor resections - hardware considerations

Glioblastoma multiforme (GBM) has long been known as the most common and aggressive form of brain malignancy. The morphological similarities of the malignant and surrounding tissue cause difficulties to distinct the tumors during surgery. In order to achieve better results in resecting malignant brain tumors, a fiber based optical system which can be used intraoperative is developed in this projec

Limitations of the Derjaguin approximation and the Lorentz-Berthelot mixing rule.

We investigate the Derjaguin approximation by explicitly determining the interactions between two spherical colloids using density functional theory solved in cylindrical coordinates. The colloids are composed of close-packed Lennard-Jones particles. The solvent particles are also modeled via Lennard-Jones interactions. Cross interactions are assumed to follow the commonly used Lorentz-Berthelot (

Context gateway for physical spaces

Context-aware computing applications dynamically change their behaviors based on the context data and services provided by multiple physical spaces in the real world, such as persons, shops, homes and offices. In this paper, we propose a generic context gateway framework to manage these heterogeneous physical spaces of context sources. The framework forms a key enabling component of a scalable con

Evolutionary consequences of climate-induced range shifts in insects.

Range shifts can rapidly create new areas of geographic overlap between formerly allopatric taxa and evidence is accumulating that this can affect species persistence. We review the emerging literature on the short- and long-term consequences of these geographic range shifts. Specifically, we focus on the evolutionary consequences of novel species interactions in newly created sympatric areas by d

Helsinki alert of biodiversity and health

Urban living in built environments, combined with the use of processed water and food, may not provide the microbial stimulation necessary for a balanced development of immune function. Many chronic inflammatory disorders, including allergic, autoimmune, metabolic, and even some behavioural disorders, are linked to alteration in the human commensal microbiota. Sedentary lifestyle is associated wit

HPLC-EAT (Environmental Assessment Tool): A tool for profiling safety, health and environmental impacts of liquid chromatography methods

A simple and efficient approach for profiling the greenness of high performance liquid chromatography (HPLC) methods is presented. This environmental assessment tool (EAT) takes into consideration the environmental, health and safety issues for all solvents involved in the chromatographic method, and calculates a total score that can be used for comparison of the greenness of different methods. A

Joint disease, the hallmark of haemophilia: What issues and challenges remain despite the development of effective therapies?

Although effective therapies for haemophilia have been available for decades, the prevention and treatment of joint disease remain major clinical concerns for all haemophilia patients. Early identification of joint disease is vital to initiate or modify treatment, and prevent arthropathy. However, there remains a need for more sensitive and accurate methods, which may also detect improvement in pa

Use of proton pump inhibitors (PPI) and history of earlier fracture are independent risk factors for fracture in postmenopausal women. The WHILA study.

Postmenopausal women in the Western world are highly burdened by osteoporotic fractures. The aim of this study is to investigate risk factors at baseline for fracture in 6416 postmenopausal women during long-term follow-up. At baseline, all women completed a questionnaire regarding background factors, diseases, current use of medications and reproductive and contraceptive history, a physical exami

Large Thermoelectric Power Factor Enhancement Observed in InAs Nanowires.

We report the observation of a thermoelectric power factor in InAs nanowires that exceeds that predicted by a single-band bulk model by up to an order of magnitude at temperatures below about 20 K. We attribute this enhancement effect not to the long-predicted 1D subband effects but to quantum-dot-like states that form in electrostatically nonuniform nanowires as a result of interference between p

Cascade catalysis of highly active bimetallic Au/Pd nanoclusters: structure-function relationship investigation using anomalous small-angle X-ray scattering and UV-Vis spectroscopy

Recently, a so-called 'crown-jewel' concept of preparation of Au/Pd-based colloidal nanoclusters has been reported [Zhang, Watanabe, Okumura, Haruta & Toshima (2011). Nat. Mater. 11, 49-52]. Here, a different way of preparing highly active Au/Pd-based nanoclusters is presented. The origin of the increased activity of Au/Pd-based colloidal bimetallic nanoclusters was unclear up to now. However,