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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

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

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

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

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

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.

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

Female genital mutilation of a karyotypic male presenting as a female with delayed puberty

BACKGROUND: Female genital mutilation (FGM) is commonly practiced mainly in a belt reaching from East to West Africa north of the equator. The practice is known across socio-economic classes and among different ethnic, religious, and cultural groups. Few studies have been appropriately designed to measure the health effects of FGM. However, the outcome of FGM on intersex individuals has never been

Incidence of acute thrombo-embolic occlusion of the superior mesenteric artery--a population-based study

OBJECTIVE: To determine the incidence of acute thrombo-embolic occlusion of the superior mesenteric artery (AOSMA) in a population-based study. MATERIAL: All clinical (n=23,446) and forensic (n=7569) autopsies performed in the city of Malmo between 1970 and 1982 (population 264,000-230,000 inhabitants). The autopsy rate was 87%. METHODS: Calculation of the incidence of AOSMA with intestinal gangre

Bi-enzyme biosensor based on NAD(+)- and glutathione-dependent recombinant formaldehyde dehydrogenase and diaphorase for formaldehyde assay

The present work reports on the development of a bi-enzyme biosensor using diaphorase from Bacillus stearothermophilus, nicotinamide adenine dinucleotide (NAD(+))- and glutathione (GSH)-dependent formaldehyde dehydrogenase (FDH) from the genetically-engineered methylotrophic yeast Hansenula polymorpha as bio-recognition elements. The sensor architecture comprises a first layer containing diaphoras

Ultrafast excited-state isomerization dynamics of 1,1 '-diethyl-2,2 '-cyanine studied by four-wave mixing spectroscopy

Excited-state dynamics and solvent-solute interactions of 1,1'-diethyl-2,2'-cyanine iodine (1122C) in alcoholic solutions are investigated using time-integrated three-pulse photon-echo spectroscopy. 1122C serves as a model compound for ultrafast photoinduced isomerizationa key process in the light reception of plants, bacteria, and human vision. The photoreaction in 1122C is interrogated in depend

InAs nanowires grown by MOVPE

Epitaxial growth of Au-assisted InAs nanowires using metal organic vapour phase epitaxy is investigated. The growth rate and morphology of nanowires as a function of growth temperature, substrate material and precursor flows are discussed. It is observed that tapering increases with both In and As precursor flows, but decreases with temperature. Finally, we report growth of InAs nanowires on both

A comparison of sole carbon source utilization patterns and phospholipid fatty acid profiles to detect changes in the root microflora of hydroponically grown crops

Sole carbon source utilization (SCSU) patterns and phospholipid fatty acid (PLFA) profiles were compared with respect to their potential to characterize root-inhabiting microbial communities of hydroponically grown crops. Sweet pepper (Capsicum annum cv. Evident), lettuce (Lactuca sativa cv. Grand Rapids), and four different cultivars of tomato (Lycopersicon esculentum cvs. Gitana, Armada, Aromata

c-Myc antisense oligonucleotides preserve smooth muscle differentiation and reduce negative remodelling following rat carotid arteriotomy

Objectives: The vascular biology of restenosis is complex and not fully understood, thus explaining the lack of effective therapy for its prevention in clinical settings. The role of c-Myc in arteriotomy-induced stenosis, smooth muscle cell (SMC) differentiation and apoptosis was investigated in rat carotids applying full phosphorothioate antisense ( AS) oligonucleotides (ODNs). Methods: Carotid a

International political economy meets historical sociology : problems and promises

Mainstream International Political Economy (IPE) and Historical Sociology share a number of concerns. This has not, however, resulted in a significant body of historical IPE literature. It is argued that Historical Sociology poses two challenges for IPE, and that these must be accommodated before the field can become historically sensitive. The first concerns the ontology of historical IPE. Wherea