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Isocyanide in Biochemistry? A Theoretical Investigation of the Electronic Effects and Energetics of Cyanide Ligand Protonation in [FeFe]-Hydrogenases

The presence of Fe-bound cyanide ligands in the active site of the proton-reducing enzymes [FeFe]-hydrogenases has led to the hypothesis that such Bronsted-Lowry bases could be protonated during the catalytic cycle, thus implying that hydrogen isocyanide (HNC) might have a relevant role in such crucial microbial metabolic paths. We present a hybrid quantum mechanical/molecular mechanical (QM/MM) s

A perspective on the characterization of colloids and macromolecules using asymmetrical flow field-flow fractionation

Asymmetrical flow field-flow fractionation (AF4) is rapidly becoming a technique of choice for the separation and characterization of complex materials. It is capable of fractionating samples over a wide size (similar to 2 nm to 50 mu m in diameter) and molecular weight range (10(3)-10(10) g/mol). It offers gentle, low shear, low pressure separation conditions which are essential to preserve the s

Doing Ethnographic Research in Chinese Families: Reflections on Methodological Concerns from Two Asian Cities

This paper compares and contrasts the ethnographic practices of two non-native researchers – a Singaporean researcher studying families in mainland China and a Swedish researcher studying Chinese families in Singapore. A novel conceptual frame of ‘radius of observation positions’ has been proposed to explicate the extent of intrusion and intimacy to which researchers may venture in the private fam

The prognostic factors and multiple biomarkers in young patients with colorectal cancer.

The incidence of colorectal cancer (CRC) in young patients (≤50 years of age) appears to be increasing. However, their clinicopathological characteristics and survival are controversial. Likewise, the biomarkers are unclear. We used the West China (2008-2013, China), Surveillance, Epidemiology, and End Results program (1973-2011, United States) and Linköping Cancer (1972-2009, Sweden) databases to

Crystal Phases in III-V Nanowires: From Random Toward Engineered Polytypism

III-V nanowires (NWs) are promising for a wide range of applications, ranging from optics to electronics, energy, and biological sensing. The structural quality of NWs is of paramount importance for the performance of such future NW-based devices. Random structural defects and polytypism occur naturally in semiconductor NWs, but progress both on the theoretical understanding and experimental contr

Surface proteins of Finegoldia magna interacting with the human host

Finegoldia magna is a Gram-positive anaerobe and a member of the normal human microflora. This bacterium is also an opportunistic pathogen and isolated from ~10% of all anaerobic infections. Reoccurring taxonomical changes and the anaerobic growth have contributed to the neglect of F. magna. The present thesis describes the identification and characterization of two novel surface proteins of F. ma

Properties of long gamma-ray bursts from massive compact binaries.

We consider the implications of a model for long-duration gamma-ray bursts in which the progenitor is spun up in a close binary by tidal interactions with a massive black-hole companion. We investigate a sample of such binaries produced by a binary population synthesis, and show that the model predicts several common features in the accretion on to the newly formed black hole. In all cases, the ac

Fluorescence resonance energy transfer between phenanthrene and PAMAM dendrimers.

We describe herein an adsorption-induced energy transfer between phenanthrene, a major environmental pollutant, and a fluorescently labeled dendrimer acting as a host molecule. We find experimentally that such energy transfer is the most efficient at a solvent pH of 8 and for a phenanthrene ratio dendrimer molar ratio of 1 ratio 2. Using molecular dynamics simulations we show that the strongest bi

Biphasic Kinetic Behavior of E. coli WrbA, an FMN-Dependent NAD(P)H: Quinone Oxidoreductase

The E. coli protein WrbA is an FMN-dependent NAD(P)H: quinone oxidoreductase that has been implicated in oxidative defense. Three subunits of the tetrameric enzyme contribute to each of four identical, cavernous active sites that appear to accommodate NAD(P)H or various quinones, but not simultaneously, suggesting an obligate tetramer with a ping-pong mechanism in which NAD departs before oxidized

Total adiponectin does not predict cardiovascular events in middle-aged men in a prospective, long-term follow-up study

Aim. Plasma total adiponectin is a marker of insulin resistance, but its role in predicting cardiovascular events is unclear. We aimed to investigate the role of adiponectin as a predictor of cardiovascular risk in middle-aged men, and to describe the association between adiponectin and glucose metabolism. Methods. In this population-based prospective study of middle-aged men (n=3885), total adipo

MINIMAL SOLUTIONS FOR DUAL MICROPHONE RIG SELF-CALIBRATION

In this paper, we study minimal problems related to dual microphone rig self-calibration using TOA measurements from sound sources with unknown positions. We consider the problems with varying setups as (i) if the internal distances between the microphone nodes are known a priori or not. (ii) if the microphone rigs lies in an affine space with different dimension than the sound sources. Solving th

Chiral symmetry and charmonium decays to two pseudoscalars

We apply hard pion Chiral Perturbation Theory to charmonium decays to pi pi, KK and eta eta. We first discuss why we expect to be able to provide results for the chiral logarithms in chi(c0) and chi(c2) decays to two pseudoscalars while for the decays from J/psi, psi(nS) and chi(c1) no simple prediction is possible. The leading chiral logarithm turns out to be absent for chi(c0), chi(c2) -> PP. Th

A brief review on convection heat transfer of fluids at supercritical pressures in tubes and the recent progress

This study presents a state-of-the-art overview on heat transfer characteristics of fluids (mainly water, carbon dioxide and hydrocarbon fuels) flowing in smooth tubes and enhanced tubes at supercritical pressures and tries to obtain a fundamental understanding of the unique characteristics. Heat transfer in enhanced tubes is much better than that in smooth tubes with a larger pressure drop penalt

A Study on In-Cycle Control of NOx Using Injection Strategy with a Fast Cylinder Pressure Based Emission Model as Feedback

The emission control in heavy-duty vehicles today is based on predefined injection strategies and after-treatment systems such as SCR (selective catalytic reduction) and DPF (diesel particulate filter). State-of-the-art engine control is presently based on cycle-to-cycle resolution. The introduction of the crank angle resolved pressure measurement, from a piezo-based pressure sensor, enables the p

Women's' premonitions prior to the death of their baby in utero and how they deal with the feeling that their baby may be unwell.

Objective. To identify if mothers to stillborn babies had had a premonition that their unborn child might not be well and how they dealt with that premonition. Design. A mixed method approach. Setting: 1 034 women answered a web questionnaire. Sample: 614 women fulfilled the inclusion criteria of having a stillbirth after the 22(nd) gestational week and answered questions about premonition. Method

Global expression profiling of low temperature induced genes in the chilling tolerant japonica rice jumli marshi.

Low temperature is a key factor that limits growth and productivity of many important agronomical crops worldwide. Rice (Oryza sativa L.) is negatively affected already at temperatures below +10°C and is therefore denoted as chilling sensitive. However, chilling tolerant rice cultivars exist and can be commercially cultivated at altitudes up to 3,050 meters with temperatures reaching as low as +4°