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Structural basis for red cell phenotypic changes in newly identified, naturally occurring subgroup mutants of the human blood group B glycosyltransferase.

BACKGROUND: Four amino-acid-changing polymorphisms differentiate the blood group A and B alleles. Multiple missense mutations are associated with weak expression of A and B antigens but the structural changes causing subgroups have not been studied. STUDY DESIGN AND METHODS: Individuals or families having serologically weak B antigen on their red cells were studied. Alleles were characterized by s

Trace gas exchange in a high-arctic valley 1. Variations in CO2 and CH4 flux between tundra vegetation types

Ecosystem exchanges of CO2 and CH4 were studied by chamber techniques in five different vegetation types in a high arctic valley at Zackenberg, NE Greenland. The vegetation types were categorized as Cassiope heath, hummocky fen, continuous fen, grass land and Salix arctica snowbed. Integrated daytime fluxes for the different vegetation types of the valley showed that the fen areas and the grasslan

Spectral Compensation for Multicarrier Communication

Spectral compensation is an information-processing technique applied in the transmitter to improve the spectral efficiency of multicarrier modulation under a given power spectral density constraint. A set of carefully chosen tones, the so-called information tones, carries data. The. remaining tones, referred to as compensation tones, are modulated with a linear combination of the data, such that t

Microbial degradation of acetonitrile using a suspended-carrier biofilm process

A microbial process for the destruction of acetonitrile has been developed. Suitable microorganisms were enriched from activated sludge by cultivation with a high selection pressure when acetonitrile was the sole source of carbon and nitrogen. The process is based on cultivating the microorganisms as a biofilm on plastic carriers. These are utilised in a stirred-tank reactor with continuous feedin

Renal replacement therapy in Sweden

Objective: The Swedish Registry for Active Treatment of Uraemia (SRAU) was founded in 1991 with the objective of documenting demographic data on patients treated for end-stage renal disease (ESRD). The aim of this study was to describe the prevalence, incidence, comorbidity risk factors and survival of patients with ESRD who underwent dialysis treatment and/or kidney transplantation in Sweden betw

Community assembly and seasonal succession of marine dinoflagellates in a temperate estuary: The importance of life cycle events

Dinoflagellate successional strategies and community structure were investigated in Perch Pond, a temperate estuary on the North American east coast by field surveys as well as laboratory investigations on growth rates, cyst maturation period, and cyst germination temperature thresholds. The dominant species were those predicted by the Smayda and Reynolds Rules of Assembly life form model. Three s

Inverse bounds and bulk properties of complex-valued two-component composites

The bulk properties of composites are known to depend strongly on the microstructure. This dependence can be quantified in terms of a representation introduced by D. Bergman, which factorizes the geometry dependence from the contrast. Based on this analytic representation of the effective permittivity, we present a general scheme to estimate the microstructural parameters such as the volume fracti

A Turbocharged Dual-Fuel HCCI Engine

A 6-cylinder truck engine is modified for turbocharged dual-fuel Homogeneous Charge Compression Ignition (HCCI) engine operation. Two different fuels, ethanol and n-heptane, are used to control the ignition timing. The objective of this study is to demonstrate high load operation of a full-size HCCI engine and to discuss some of the typical constraints associated with HCCI operation. This study pr

Biomassebaserade energibärare för transportsektorn

Det finns en stor potential för ett ökat utnyttjande av biomassa för energiändamål i Sverige. En ökad användning av biomassa skulle kunna bidra till att minska utsläppen av koldioxid från förbränning av fossila bränslen, minska beroendet av importerade fossila energibärare samt påverka den regionala och lokala miljösituationen såväl positivt som negativt. Föreliggande studie behandlar framför alltThere is a large potential for increasing the use of biomass for energy purposes in Sweden. Increasing the use of biomass can reduce emissions of carbon dioxide (CO2) from fossil-fuel combustion and dependence on imported fossil fuels. Furthermore, increased biomass use will affect emissions of other air pollutants than carbon dioxide as well as environmental impacts from land use. The study deals

A human cell surface receptor activated by free fatty acids and thiazolidinedione drugs.

Fatty acids, which are essential nutritional components, are also involved in cardiovascular and metabolic diseases. Here we report a human cell surface receptor that we name free fatty acid receptor (FFAR), because it is specifically activated by medium to long-chain free fatty acids. The receptor belongs to the class of seven-transmembrane, G-protein coupled receptors (GPCRs) and also mediates r

Simuleringar och analys av V. Cholerae odling där feeden styrs genom återkoppling från ättiksyramätningar

På Linköpings tekniska högskola har man tillgång till många olika sätt att mäta ättiksyra i en bioreaktor. Utrustningen för att mäta ättiksyra består av en NIR (near infrared spectroscopy) som mäter online och en samplingstid på sekund nivå kan uppnås. HPLC (high-performance liquid chromatography) finns det också tillgång till. Där räknar man med att ta prover var 15 min och att själva analysen ta

Fractionation of the thylakoid membrane from Dunaliella salina – heterogeneity is found in Photosystem I over a broad range of growth irradiance

Thylakoids from the green alga, Dunaliella salina, were fragmented by sonication and the appressed grasna membranes separated from stroma lamellae by partitioning in aqueous two-phase systems. The concentration and antenna size of Photosystem I in the two membrane domains were determined for cultures grown at three different light intensities. Although the antenna size of both PS is decreased with

Control Structure Assessment in an Industrial Control System

This paper describes the implementation of a structure assessmentmethod in an industrial control system. The method uses available signals to evaluate if a given signal can be used for additional feed forward control action to improve the performance of a control loop.

Flux reduction of ultrafiltration membranes with different cut-off due to adsorption of a low-molecular-weight hydrophobic solute-correlation between flux decline and pore size

The flux of ultrafiltration membranes may be severely reduced when treating low-molecular-weight hydrophobic solutes even though the cut-off of the membrane is orders of magnitudes greater than the size of the solute molecules. In this investigation, the flux reduction was correlated to the membrane pore size using octanoic acid as a model substance. As a comparison, the pore size was also determi

Evaluating the effects of place marketing campaigns on interregional migration in Sweden

During the last few years, Swedish municipalities have become increasingly engaged in competition to attract in-migrants. An important element of these efforts has been the use of place- marketing campaigns and promotion. Very little is known, however, about these attempts in terms of the number of municipalities involved, economic efforts, ways of marketing, target groups, etc. Furthermore, and m

T cells that are naturally tolerant to cartilage-derived type II collagen are involved in the development of collagen-induced arthritis

The immunodominant T-cell epitope that is involved in collagen-induced arthritis (CIA) is the glycosylated type II collagen (CII) peptide 256-270. In CII transgenic mice, which express the immunodominant CII 256-270 epitope in cartilage, the CII-specific T cells are characterized by a partially tolerant state with low proliferative activity in vitro, but with maintained effector functions, such as

Ambiguous configurations for the 1D structure and motion problem

In this paper we investigate, determine and classify the critical configurations for solving structure and motion problems for 1D retina vision. We give a complete categorization of all ambiguous configurations for a 1D (calibrated or uncalibrated) perspective camera irrespective of the number of points and views. It is well-known that the calibrated and uncalibrated case are linked through the ci