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Evidence for Two Mg Related Acceptors in GaN

The optical signatures of Mg-related acceptors in GaN have been revisited in samples specifically grown on bulk GaN templates, to avoid strain broadening of the optical spectra. Bound-exciton spectra can be studied in these samples for Mg concentrations up to [Mg]approximate to 2x10(19) cm(-3). Contrary to previous work it is found that instabilities in the photoluminescence spectra are not due to

Effects of artificial acid rain on microbial activity and biomass

The emission of air pollutants which form acid components in rain and snow represents a threat to natural ecosystems. Increased leaching of nutrients from soils (ABRAHAMSEN et al. 1976b), decreased pHvalues in lakes and changes in fish populations (SCHOFIELD 1976) have been suggested as some of the consequences of the increased acidity of rain. Scandinavian coniferous forests are very stable ecosy

Influence of intensified insulin regimen on quality of life and metabolic control in insulin-dependent diabetes mellitus

Seventy-eight non-randomized patients with IDDM, aged 33.8 +/- 9.6 years (mean +/- S.D.), with a duration of diabetes of 16.6 +/- 9.5 years and a HbA1c level of 8.0% +/- 1.5 at baseline were included in the study. The effects of a change from a 3-dose insulin regimen using conventional syringes to a treatment mode using 4 injections per day with a pen injector on metabolic control, perceived distr

Propagation of transient electromagnetic waves in time-varying media-direct and inverse scattering problems

Wave propagation of transient electromagnetic waves in time-varying media is considered. The medium, which is assumed to be inhomogeneous and dispersive, lacks invariance under time translations. The spatial variation of the medium is assumed to be in the depth coordinate, i.e. it is stratified. The constitutive relations of the medium are a time integral of a generalized susceptibility kernel and

Length of the antibody heavy chain complementarity determining region 3 as a specificity-determining factor

lThe antigen binding site of an antibody is made up of residues residing in six hypervariable loops of the heavy and light chains. In most cases several or all of these loops are required for the establishment of the antigen-binding surface. Five of these loops display a limited diversity in length and sequence while the third complementarity determining region (CDR) of the heavy chain is highly d

Minimization of immunosuppressive therapy after renal transplantation: Results of a randomized controlled trial

Modern immunosuppressive regimens reduce the acute rejection rate by combining a cornerstone immunosuppressant like tacrolimus or cyclosporine with adjunctive agents like corticosteroids, mycophenolate mofetil (MMF) or azathioprine, often associated with untoward side effects. A 6-month randomized study was conducted in 47 European centers. Triple therapy with tacrolimus (trough levels 5-15 ng/mL)

Elevated plasma homocysteine concentration in elderly patients with mental illness is mainly related to the presence of vascular disease and not the diagnosis

Background: Plasma total homocysteine (tHcy) is often elevated in patients with mental illness. Since patients with mental illness and vascular disease exhibit a higher plasma tHcy concentration than patients without vascular disease, it is possible that elevated plasma tHcy in mental illness is mainly due to concomitant vascular disease. Methods: We have investigated plasma tHcy, cobalamin/folate

Specific tissue expression and cellular localization of human apolipoprotein M as determined by in situ hybridization

Apolipoprotein M (apoM) is a recently discovered human apolipoprotein predominantly present in high-density lipoprotein (HDL), and in minor proportion in triglyceride-rich lipoprotein (TGRLP) and low-density lipoprotein (LDL). The gene coding for apoM has been detected in all mammal genomes. The function of apoM is unknown yet. In the present study, we demonstrated that apoM is exclusively express

Risk assessment of false-positive quantitative real-time PCR results in food, due to detection of DNA originating from dead cells

Real-time PCR technology is increasingly used for detection and quantification of pathogens in food samples. A main disadvantage of nucleic acid detection is the inability to distinguish between signals originating from viable cells and DNA released from dead cells. In order to gain knowledge concerning risks of false-positive results due to detection of DNA originating from dead cells, quantitati

Rapid production of cellulase-free xylanases by solventogenic Clostridia from rumen

Xylanases without contaminating cellulases are produced by a wide variety of aerobic bacteria and fungi but anaerobic organisms producing such enzymes are rare. Clostridial species viz., Clostridium beijerinckii LU-1, C. acetobutylicum LU-1, C. butyricum and C. bifermentans LU-1 isolated from rumen produced xylanase (E.C. 3.2.1.8) of 1.5-4.2 U/ml on oat spelt xylan as sole carbon source. Cellulose

Stent Thrombosis in Sweden A Report From the Swedish Coronary Angiography and Angioplasty Registry

Background-The objective was to evaluate the role of risk factors and stent type for stent thrombosis (ST) using a large real world registry. Methods and Results-We evaluated all consecutive coronary stent implantations in Sweden from May 1, 2005, to June 30, 2007. All cases of ST, documented in the Swedish coronary angiography and angioplasty registry until September 21, 2008, were analyzed. ST w

Islet amyloid polypeptide inhibits glucagon release and exerts a dual action on insulin release from isolated islets.

We have studied the influence of a wide concentration range of islet amyloid polypeptide (IAPP) on both glucagon and insulin release stimulated by various types of secretagogues. In an islet incubation medium devoid of glucose, the rate of glucagon release being high, we observed a marked suppressive action by low concentrations of IAPP, 10−10 and 10−8 M, on glucagon release. Similarly, glucagon r

Low-cost evaluation of the exchange Fock matrix from Cholesky and density fitting representations of the electron repulsion integrals

The authors propose a new algorithm, "local K" (LK), for fast evaluation of the exchange Fock matrix in case the Cholesky decomposition of the electron repulsion integrals is used. The novelty lies in the fact that rigorous upper bounds to the contribution from each occupied orbital to the exchange Fock matrix are employed. By formulating these inequalities in terms of localized orbitals, the scal

Identification of the probable inhibitory reactive sites of the cysteine proteinase inhibitors human cystatin C and chicken cystatin

When an excess of human cystatin C or chicken cystatin was mixed with papain, an enzyme-inhibitor complex was formed immediately. The residual free cystatin was then progressively converted to a form with different electrophoretic mobility and chromatographic properties. The modified cystatins were isolated and sequenced, showing that there had been cleavage of a single peptide bond in each molecu

TGF beta receptor II gene deletion in leucocytes prevents cerebral vasculitis in bacterial meningitis

In bacterial meningitis, chemokines lead to recruitment of polymorphonuclear leucocytes (PMN) into the CNS. At the site of infection in the subarachnoid space, PMN release reactive oxygen species, reactive nitrogen intermediates (RNI) and interleukin-1 beta (IL-1 beta). Although these immune factors assist in clearance of bacteria, they also result in neuronal injury associated with meningitis. Tr

Expansion of signal pathways in the ectomycorrhizal fungus Laccaria bicolor- evolution of nucleotide sequences and expression patterns in families of protein kinases and RAS small GTPases.

* The ectomycorrhizal fungus Laccaria bicolor has the largest genome of all fungi yet sequenced. The large genome size is partly a result of an expansion of gene family sizes. Among the largest gene families are protein kinases and RAS small guanosine triphosphatases (GTPases), which are key components of signal transduction pathways. * Comparative genomics and phylogenetic analyses were used to e