Development and Characterization of a Multiplex Assay to Quantify Complement-Fixing Antibodies against Dengue Virus

Antibodies capable of activating the complement system (CS) when bound with antigen are referred to as “complement-fixing antibodies” and are involved in protection against Flaviviruses. A complement-fixing antibody test has been used in the past to measure the ability of dengue virus (DENV)-specific serum antibodies to activate the CS. As originally developed, the test is time-consuming, cumbersome, and has limited sensitivity for DENV diagnosis. Here, we developed and characterized a novel multiplex anti-DENV complement-fixing assay based on the Luminex platform to quantitate serum antibodies against all four serotypes (DENV1-4) that activate the CS based on their ability to fix the complement component 1q (C1q). The assay demonstrated good reproducibility and showed equivalent performance to a DENV microneutralization assay that has been used to determine DENV serostatus. In non-human primates, antibodies produced in response to primary DENV1-4 infection induced C1q fixation on homologous and heterologous serotypes. Inter-serotype cross-reactivity was associated with homology of the envelope protein. Interestingly, the antibodies produced following vaccination against Zika virus fixed C1q on DENV. The anti-DENV complement fixing antibody assay represents an alternative approach to determine the quality of functional antibodies produced following DENV natural infection or vaccination and a biomarker for dengue serostatus, while providing insights about immunological cross-reactivity among different Flaviviruses.     

Functional analysis of yeast essential genes using a promoter-substitution cassette and the tetracycline-regulatable dual expression system

A promoter-substitution cassette has been constructed that allows one-step substitution of chromosomal gene promoters for the tetracycline-regulatable tetO promoter in yeast cells, which uses kanMX4 as selective marker for geneticin resistance. Oligonucleotides for PCR amplification of the cassette are designed to allow homologous recombination through short flanking regions of homology with the upstream sequences of the chromosomal gene, upon transformation of target cells. By testing three essential genes of chromosome XV (YOL135c, YOL142w and YOL144w), the system causes tetracycline-dependent conditional growth of the cells, being modulatable by intermediate concentrations of the effector. Analysis of terminal phenotypes of the promoter-substituted cells in the presence of the antibiotic may facilitate functional analysis of essential orphan genes. © 1998 John Wiley & Sons, Ltd.     

Partial Discharge Measurement of OCP-Tapes in Rotating Electrical Machines

Nowadays, PD （partial discharge） measurements are a crucial part of the preventive maintenance of electrical equipment within high voltage engineering. Especially for electrical machines, both the supplier and the user are interested in the results of PD measurements. However, PDs hardly represent the cause of the failure, more likely they are claimed as the outcome of a failure. This paper deals with the insulation of a 6 kV electrical machine, whereas PD measurements were carried out at a single stator from wound coils. During manufacturing, these coils were equipped with different materials for the OCP （outer corona protection）. Using different PD measurement systems and different bandwidths, investigations of the PD behavior of the coils were carried out. Additionally, the surface resistivity of the corona protection was determined. As a result, conclusions for the correlations between the resistance of the OCP as well as the PD behavior are stated. Furthermore, the influence of using different measurement systems, different measuring circuits, and different bandwidths is shown.     

Mechanics of Elastomer--Shim Laminates

The mechanics of laminates of elastomer and shims of high modulus material are reviewed. Such structures are often built to provide engineering components with specified, and quite different, stiffnesses in different modes of deformation. The shims may either be rigid or flexible, flat or curved, but are usually close to inextensible, being made of a high modulus material such as steel. On the other hand, rubber has an exceptionally low shear modulus, about one thousandth of its bulk modulus, so that shear of the rubber layers and flexure of the high modulus layers (if thin) are the dominant mechanisms of deformation of the composite. In comparison, extension of the layers and changes to their separation are highly constrained.
Modes of failure are addressed as well as force-deformation behaviour. For compression normal to the laminations, the shear in the rubber results in in-plane tension in the shims, possibly leading to tensile failure. For tension normal to the laminations, the elastomer can cavitate, which would relieve the shear in it and hence the in-plane compressive stress applied to the shim. In flexure, shear in the rubber can apply in-plane compressive stress to the shims and cause buckling failure.     

Capture of carbon dioxide by an ion-exchange resin: Influence of gas humidity on capture mechanisms

This paper evaluates moisture content effects on CO₂ capture of an ion-exchange resin (IER) functionalised with a primary amine group. IER capacities were determined by breakthrough with an inlet gas containing 10 vol% CO₂, nitrogen and various moisture contents. Three types of behaviour were identified according to humidity level. In saturated air conditions, the stoichiometry could be justified by carbonates and bicarbonates fixation. In dry conditions, we suspect a joint physical adsorption and reaction mechanism. For intermediate humidity, the stoichiometry of 1 CO₂ for 1 amine group is consistent with a bicarbonate fixation or carbamic acid formation.     

The effect of microstructure on hydrogen permeability of high strength steels

Hydrogen diffusivity and trapping have been studied in two advanced high strength steel grades and model samples using electrochemical permeation test. Microstructures of CP1000 and DP1000 steels consist of ferrite, martensite and a small fraction of retained austenite. In addition, bainite is present in CP1000. Model phases with predominance of a particular phase have been prepared by specific heat treatment. DP1000 has shown the lowest diffusivity among all materials, while ferritic model sample has shown the highest. Differences in hydrogen diffusion coefficient values are linked to trapping microstructural characteristics and grain size.     

Ilizarov procedure in pseudarthrosis

The treatment of nonunions has made an important development through the work of Ilizarov describing the principles of compression and distraction by using the ring-fixator. While local compression is sufficient in hypertrophic nonunions, the treatment of choice for atrophic infected nonunions with bony defects is a corticotomy followed by a segmental transport, especially in case of an osseous defect larger than 3 cm. Primary shortening poses a better starting point both for soft-tissue reconstruction and for early docking. External fixation systems are the ring-fixator, the unilateral fixator and hybrid systems combining both fixation methods. The use of a ring-fixator makes a shorter time of osseous consolidation possible when compared to a unilateral system (25,8 d/cm - 35,8 d/cm). Soft-tissue reconstruction before initiation of transport also shortens the time of osseous consolidation compared to later soft-tissue coverage. A docking-region in the metaphyseal area is supported by minimal internal fixation and cancellous bone graft. Segmental transport is complicated by local infection, regenerate failure (4.3% and regenerate fracture (2.9%).     

Prospective study of the significance of contact sensitization caused by metal implants

Cell nuclei of mouse hepatoma contain various proteoglycans (PG) which include heparan sulfate proteoglycan (HS-PG), dermatan sulfate proteoglycan (DS-PG), and chondroitin sulfate proteoglycan (CS AC-PG). The latter is not found in cell nuclei of normal mouse liver. Heparan sulfate (HS) and dermatan sulfate (DS) are the main constituents of carbohydrate chains of nuclear proteoglycans of tumor and normal cells, respectively. Changes in the composition of nuclear PG during malignant transformation are discussed considering the concept of their possible involvement in the regulation of cell mitotic activity.     

Power Quality und technisches Risikomanagement

Ohne Zusammenfassung Kurzfassung eines Vortrags, gehalten anl?sslich der 39. Fachtagung der ?sterreichischen Gesellschaft für Energietechnik im ?VE, die am 18. und 19. Oktober 2001 in Salzburg stattfindet.     

Improved Osteointegration of Ti-6Al-4V-implants of Different Surface Texture by the Use of Bone Morphogenetic Protein-3 (BMP-3)

1Introduction Withregardstolong termstabilityandimplantfixa tionthedevelopmentofnon cementedimplantswhichfos tertheirownosteointegrationbywayofreleasingosteoin duciveproteinsisofgreatimportance.Thus,thedevelop mentofsuccessfulcombinationsofosteoinductivef…