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Relaxed dynamic programming in switching systems

In order to simplify computational methods based on dynamic programming, a relaxed procedure based on upper and lower bounds of the optimal cost was recently introduced. The convergence properties of this procedure are analysed here. In particular, it is shown that the computational effort in finding an approximately optimal control law by relaxed value iteration is related to the polynomial degre

Logistics integration in horizontal mergers and acquisitions

In this article, we describe the integration of logistics after Mergers and Acquisitions (M&As) of firms within the same industry and, same industry level (i.e. horizontal M&As). First, we present a review of the literature on M&As and conclude that operational issues, in general, and logistics issues, in particular, have received little attention. In parallel with the literature revie

Recrystallization of waxy maize starch during manufacturing of starch microspheres for drug delivery: Optimization by experimental design

Gelatinized starch/water dispersions with a water content of 70% w/w were studied in order to evaluate the influence of the incubation time at two fixed temperatures (6 and 37 degrees C) on the recrystallization behavior. The starch material was produced from waxy maize starch by acid hydrolysis followed by a mechanical treatment, i.e. a high pressure homogenization. Empirical models for the recry

Typing of hepatitis C virus isolates by DNA enzyme immunoassay

Recently, at least six types of hepatitis C viruses (HCV) have been identified. Different types of HCV appear to possess different pathogenic properties and a different sensitivity to interferon treatment. Typing of HCV isolates may therefore be an important diagnostic procedure. We report on a new method for identification of HCV types 1a, 1b, 2a, 2b and 3a which are most prevalent in Europe, Nor

IdeS, a highly specific immunoglobulin G (IgG)-cleaving enzyme from Streptococcus pyogenes, is inhibited by specific IgG antibodies generated during infection

IdeS, a recently discovered cysteine proteinase secreted by the important human pathogen Streptococcus pyogenes, interferes with phagocytic killing by specifically cleaving the heavy chain of immunoglobulin G. The fact that the enzyme targets one of the key molecules of the adapted immune response raised the question of whether an antibody response against IdeS could inhibit, i.e., neutralize, enz

Patch testing with methyldibromo glutaronitrile, a multicentre study within the EECDRG

Contact allergy to and allergic contact dermatitis from methyldibromo glutaronitrile (MDBGN) have frequently been reported. As there has been no agreement on which MDBGN test preparation to use, a study was initiated to help determine the optimal patch test preparation for MDBGN. 2661 consecutively patch tested patients at 11 test clinics representing 9 European countries participated. Petrolatum

Hepatitis C virus RNA in blood donor sera detected by the polymerase chain reaction: comparison with supplementary hepatitis C antibody assays

The low specificity of screening ELISAs for antibodies to hepatitis C virus in blood donors has called for confirmatory tests. Two types of supplementary antibody assays are available, recombinant immunoblot assays (RIBA-1 and RIBA-2) and an antibody consumption test referred to as a neutralization assay. Amplification of viral nucleic acid by the polymerase chain reaction (PCR) provides an antibo

Silicone Membrane Equilibrator: Measuring Chemical Activity of Nonpolar Chemicals with Poly(dimethylsiloxane) Microtubes Immersed Directly in Tissue and Lipids.

The chemical activity of organic chemicals directs their diffusion and partitioning and is consequently crucial for their transport, distribution, and toxic effects. A silicone membrane equilibrator is introduced for measuring the chemical activity of nonpolar organic chemicals in lipid-rich samples: (I) A 6 m poly(dimethylsiloxane) (PDMS) microtube (300 mum i.d., 640 mum o.d.) was placed in a sam

Molecular cloning and expression of human myocardial cGMP-inhibited cAMP phosphodiesterase

We have cloned a cDNA for a myocardial cGMP-inhibited cAMP phosphodiesterase (cGI PDE) from a human heart cDNA library in lambda Zap II. The open reading frame [3.5 kilobases (kb)] of cDNA clone n.13.2 (7.7 kb) encodes a protein of 125 kDa. In Northern blots of total human ventricle RNA, a single mRNA species (8.3 kb) hybridized with a 4-kb EcoRI restriction fragment of clone n.13.2 cDNA (containi

Effect kinetics of desmopressin-induced platelet retention in healthy volunteers treated with aspirin or placebo

Desmopressin is often used for haemostatic treatment in platelet dysfunction, but the effect kinetics of platelet responses and the mechanism of action are poorly known. This study aimed to determine the kinetics of platelet function responses induced by desmopressin in healthy volunteers treated with aspirin or placebo. Another aim was to correlate platelet responses to changes of von Willebrand

Microbial BOD sensor for monitoring treatment of wastewater from a rubber latex industry

A cell-based biosensor system was designed for monitoring an anaerobic process for treatment of high biochemical oxygen demand (BOD) levels in wastewater samples from a factory processing concentrated rubber latex. The BOD biosensor used immobilized mixed culture of microorganisms as the biological sensing element and an oxygen electrode as the transducer. The assay principle is based on the deter

Aglomerular hemipteran antennal lobes – Basic neuroanatomy of a small nose

We have compared the basic organization of the primary olfactory centre, the antennal lobe (AL), in 4 hemipteran species representing the 2 major lineages in this order. The Homoptera were represented by the psyllid Trioza apicalis and its aphid relatives the grain aphid Sitobion avenae Fabricius and the rose-grain aphid Metopolophium dirhodum Walker, whereas the Heteroptera were represented by th

Influence of strain and cultivation procedure on the performance of simultaneous saccharification and fermentation of steam pretreated spruce

Yeast to be used in simultaneous saccharification and fermentation (SSF) of lignocelluloses materials has to be prepared in a separate cultivation step. The effects of the cultivation procedure on the performance of SSF of steam pretreated softwood were studied in the current work. The yeast used in the SSF was either directly commercially available Baker's yeast (as packaged yeast) or the same st

Integration of ERG gene mapping and gene-expression profiling identifies distinct categories of human prostate cancer

OBJECTIVE To integrate the mapping of ERG alterations with the collection of expression microarray (EMA) data, as previous EMA analyses have failed to consider the genetic heterogeneity and complex patterns of ERG alteration frequently found in cancerous prostates. MATERIALS AND METHODS We determined genome-wide expression levels with GeneChip Human Exon 1.0 ST arrays (Affymetrix, Santa Clara, CA,

Growth and development of human muscle: a quantitative morphological study of whole vastus lateralis from childhood to adult age

The mechanisms underlying the increase in volume of muscle tissue, and the functional development of muscle fibers from childhood through adolescence to adult age, have been studied. Cross sections of autopsied whole vastus lateralis muscle from 22 previously physically healthy males, 5 to 37 years of age, were prepared enzyme histochemically (myofibrillar ATPase) and examined morphometrically. Th