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Effect of impurities on structural and electrochemical properties of the Ni-YSZ interface.

The changes in interface structure and chemical composition of a 99.995% pure nickel/yttria-stabilised zirconia (YSZ) interface were examined after heat treatment at 1000 °C in 97% H2/3% H2O with and without polarisation. Impedance spectroscopy was used for electrochemical characterisation. The results were compared to earlier investigations of a less pure nickel/YSZ interface. The pure interface

Is size-assortative mating important for rapid pigment differentiation in a freshwater isopod?

Identifying mechanisms behind assortative mating is central to the understanding of ecological divergence and speciation. Recent studies show that populations of the freshwater isopod Asellus aquaticus can rapidly become locally differentiated when submerged Chara vegetation expands in lakes. In the novel Chara habitat, isopods have become lighter pigmented and smaller than in ancestral reed stand

Amplification of the cyclin D1 gene is associated with tumour subsite, DNA non-diploidy and high S-phase fraction in squamous cell carcinoma of the head and neck

Amplification of CCND1 (cyclin D1 gene) in squamous cell carcinoma of the head and neck (SCCHN) is correlated to poor prognosis. The purpose of this study was to investigate whether CCND1 amplification is related to different subsites and also to DNA ploidy status and S-phase fraction (SPF). Biopsies from 67 patients with SCCHN were analysed for CCND1 amplification by fluorescence in situ hybridis

In-situ ESEM study of thermo-mechanical fatigue crack propagation

An experimental procedure to determine crack propagation rates under thermo-mechanical loading is presented. The experiments were conducted in-situ within an environmental scanning electron microscope, and images of the crack tip region were taken throughout the load cycles. The mechanical load was provided by a load controlled electrically driven load stage. Thermal heating of the crack region wa

Preoperative Antibiotics Before Endourologic Surgery: Current Recommendations

The use of antibiotic prophylaxis is an accepted and widely practiced feature of modern surgery. The prevention and control of infection is a priority in healthcare worldwide, and the emergence of antibiotic resistance is a global phenomenon. Hence, rational use of antibiotics is essential. We discuss the guidelines published with regard to endourologic procedures and review the limited evidence c

Microalbuminuria and risk factors in type 1 and type 2 diabetic patients

A prospective study of normoalbutninuric diabetic patients was performed between 1997 and 2002 on 4097 type 1 and 6513 type 2 diabetic patients from the Swedish National Diabetes Register (NDR); mean study period, 4.6 years. The strongest independent baseline risk factors for the development of microalbuminuria (20-200 mug/min) were elevated HbA(1c) and diabetes duration in both types 1 and 2 diab

Dispersion of single walled. carbon nanotubes. Comparison of different dispersing strategies for preparation of modified electrodes toward hydrogen peroxide detection

Four different dispersing agents for solubilisation of single walled carbon nanotubes (SWNT) are here compared. Dispersing agents used here can be divided into the group of organic solvents (dimethylformamide and cyclohexanone) and charged polymers (Nafion and chitosan). Charged polymers are more efficient dispersing agents allowing quicker dispersion of nanotubes compared to solvents. Moreover ch

Structural characterization of the stringent response related exopolyphosphatase/guanosine pentaphosphate phosphohydrolase protein family

Exopolyphosphatase/guanosine pentaphosphate phosphohydrolase (PPX/GPPA) enzymes play central roles in the bacterial stringent response induced by starvation. The high-resolution crystal structure of the putative Aquifex aeolicus PPX/GPPA phosphatase from the actin-like ATPase domain superfamily has been determined, providing the first insights to features of the common catalytic core of the PPX/GP

A multipurpose capacitive biosensor for assay and quality control of human immunoglobulin G.

We report a flow-injection biosensor system with a capacitive transducer for assay and quality control of human immunoglobulin G (hIgG). The sensing platform is based on self-assembled monolayers (SAMs) of carboxylic acid terminated alkyl-thiols with covalently attached concanavalin A. The electrochemical characteristics of the sensor surface were assessed by cyclic voltammetry using a permeable r

Dissociation of the Inflammatory Reaction following PCI for Acute Myocardial Infarction

OBJECTIVES: Neutrophils are activated and infiltrate the myocardium after ischemia and reperfusion. The involvement of neutrophils in irreversible reperfusion injury is suggested by numerous experimental studies. The aim of this study was to investigate markers of neutrophil activation following reperfusion of acute myocardial infarction (AMI) accomplished with percutaneous coronary intervention (

Thermodynamics of α- and β-structure formation in proteins

An atomic protein model with a minimalistic potential is developed and then tested on an α-helix and a β-hairpin, using exactly the same parameters for both peptides. We find that melting curves for these sequences to a good approximation can be described by a simple two-state model, with parameters that are in reasonable quantitative agreement with experimental data. Despite the apparent two-stat

Long-time record of fire and open canopy in a high biodiversity forest in southeast Sweden

We studied a ca 200 ha large forest site that holds an exceptionally large number of red-listed saproxylic beetles. We conducted pollen, charcoal and dendroecological analyses to reveal the long-term stand-level history of the site. We also investigated which of the red-listed saproxylic beetles recorded at the site are probably dependent on forest fires or structures that are created by fires. Po

Stellar chemical abundances with the GHRS

The accurate quantitative analysis of high resolution ultraviolet spectra of ultra-sharp-lined early-type, chemically peculiar stars, obtained with the Goddard High Resolution spectrograph on the Hubble Space Telescope, has been made possible by the synergism between state-of-the-art astro-physics and state-of-the-art atomic spectroscopy. We illustrate this with several examples, including the dis

Structure of SP-B/DPPC Mixed Films Studied by Neutron Reflectometry.

The structures of films of SP-B and mixtures of SP-B and DPPC at the air/water interface have been studied by neutron reflectometry (NR) and Langmuir film balance methods. From the film balance studies we observe that at very high pressures the isotherms of pure DPPC and SP-B/DPPC mixtures very nearly overlay one another, suggesting that the SP-B is being excluded from the film. The use of multipl