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Vaccinia scars associated with improved survival among adults in rural Guinea-Bissau

BACKGROUND: In urban Guinea-Bissau, adults with a vaccinia scar had better survival but also a higher prevalence of HIV-2 infection. We therefore investigated the association between vaccinia scar and survival and HIV infection in a rural area of Guinea-Bissau. METHODOLOGY/PRINCIPAL FINDINGS: In connection with a study of HIV in rural Guinea-Bissau, we assessed vaccinia and BCG scars in 193 HIV-1

Early-Late Permian palynostratigraphy and palaeobiogeography of Vestfjella, Dronning Maud Land, Antarctica

The preliminary results of a palynological investigation of 62 samples from the southern section of a sedimentary sequence exposed at Fossilryggen in the Vestfjella mountain range in Dronning Maud Land, Antarctica are reported. The sequence, which is cut by dolerite dykes, is considered to have been deposited in a near-shore marine environment. Palynomorphs recovered show high degrees of thermal a

Quality control of measured x-ray beam data

The purpose of this study was to examine whether the quality of measured x-ray beam data can be judged from how well the data agree with a semiempirical formula. Tissue-phantom ratios (TPR) and output factors for several accelerators in the energy range 4-25 MV were fitted to the formula, separating the dose contributions from primary and phantom-scattered photons. The former was described by expo

A general framework for the parametrization of hierarchical models

In this paper, we describe centering and noncentering methodology as complementary techniques for use in parametrization of broad classes of hierarchical models, with a view to the construction of effective MCMC algorithms for exploring posterior distributions from these models. We give a clear qualitative understanding as to when centering and noncentering work well, and introduce theory concerni

Morphological Features and Mismatch Repair in Colorectal Tumors

Corlorectal cancer affects 5% of individuals in the Western world and heredity is estimated to cause at least 10% of the tumors. Defective mismatch repair (MMR) is a tumorigenic mechanism through which about 15% of colorectal cancer develops and this feature characterizes tumors associated with Hereditary Nonpolyposis Colorectal Cancer (HNPCC) or Lynch syndrome. The underlying molecular mechanism

Fatty-acid-displaced transcriptional repressor, a conserved regulator of cytochrome P450 102 transcription in Bacillus species

Bacillus subtilis strain 168 encodes two flavocytochromes P450, Cyp102A2 and Cyp102A3. The cyp102A3 gene is preceded by, and organized in an operon with, a gene for a transcriptional regulator, encoded by fatR. The paralogous gene, cyp102A2, is most likely transcribed as a mono-cistronic message. We show that fatR encodes a protein that binds to an operator sequence that is present upstream of its

Hällristarnas hem - Gårdsbebyggelse och struktur i Pryssgården under bronsålder

Popular Abstract in Swedish Syftet med avhandlingen har varit att försöka förstå bronsålderns samhälle och ideologi utifrån bebyggelsens inneboende symbolik, utformning och struktur. I alla samhällen utgör hushållet den minsta sociala enheten. Huset och hushållen utgör centrum för människors liv. Hur människorna har valt att organisera sin tillvaro kan ha skett i en samverkan med den övergripande The purpose of this thesis is an attempt to comprehend the society and the ideology of the Bronze Age from the inherent symbolism, shape and structure of buildings. In every society, the smallest social unit is the household. The house and the household are central in the lives of people. They made their choices to organize their existence in a symbiotic cooperation with the general cosmology and

Potential effects of climate change on plant species in the Faroe Islands

Aim To identify the effect of climate change on selected plant species representative of the main vegetation types in the Faroe Islands. Due to a possible weakening of the North Atlantic Current, it is difficult to predict whether the climate in the Faroe Islands will be warmer or colder as a result of global warming. Therefore, two scenarios are proposed. The first scenario assumes an increase in

Myosin composition and functional properties of smooth muscle from the uterus of pregnant and non-pregnant rats

The myosin heavy chain stoichiometry and the force-velocity relation have been determined in the myometrium of the non-pregnant and pregnant rat. The relative proportions of the slower migrating heavy chain (MHC1) greatly exceeded that of the faster migrating heavy chain (MHC2) as shown by electrophoresis on SDS 4%-polyacrylamide gels. The ratios of MHC1/MHC2 were 2.2/1 in the non-pregnant rats, 2

Amphiphilic polymer gel electrolytes. I. Preparation of gels based on poly(ethylene oxide) graft copolymers containing different ionophobic groups

Amphiphilic graft copolymers were prepared via the radical copolymerization of poly(ethylene oxide) (PEO) macromonomers with fluorocarbon or hydrocarbon acrylates in toluene with 2,2 ' -azobisisobutyronitrile (AIBN) as an initiator. H-1 NMR spectroscopy confirmed that the composition of the graft copolymers corresponded well to the monomer feed. For gel electrolytes prepared from the amphiphilic c

Temperature changes within samples in heat conduction calorimeters

So-called isothermal calorimeters are often built on the heat conduction principle. This may sound as a contradiction, as heat conduction is a result of non-isothermal conditions, but most measurements with microcalorimeters and other such instruments are essentially isothermal as the temperature differences within the instruments are in the order of 10 mK. This paper presents simple methods to es

A clinically applicable method for determining the three major alleles at the Duffy (FY) blood group locus using polymerase chain reaction with allele-specific primers

BACKGROUND: The clinically significant antigens of the Duffy (Fy [FY]) blood group system are expressed on the red cell form of the FY glycoprotein, a promiscuous chemokine receptor and also a receptor for malarial parasites. After the cloning of cDNA coding for FY glycoprotein, the molecular basis of the three major alleles (Fya/Fyb/Fy) has been established. Because of the mistyping of the silent

Influence of alpha-ketoglutarate on cortical bone density, geometrical properties and mechanical endurance of the humerus in turkeys

The aim of this study was to estimate an influence of alpha-ketoglutarate (AKG) on volumetric bone density and geometrical and mechanical properties of the humerus in farm turkeys. All birds were kept under standard rearing conditions with constant access to water and appropriate feed, supplied in accordance with the stage of production cycle. Bone samples were collected 14 weeks after beginning o

Compact medical fluorosensor for minimally invasive tissue characterization

A compact fiber-optic point-measuring fluorosensor fully adapted to clinical studies is described. The system can use two excitation wavelengths, 337 and 405 nm, obtained from a nitrogen laser directly, or after dye laser conversion, respectively. The image intensifier used in the spectrometer can be gated with a variable time delay, allowing also time-resolved spectra to be extracted, with a time

Calibration and assessment of channel-specific biases in microarray data with extended dynamical range

Background: Non-linearities in observed log-ratios of gene expressions, also known as intensity dependent log-ratios, can often be accounted for by global biases in the two channels being compared. Any step in a microarray process may introduce such offsets and in this article we study the biases introduced by the microarray scanner and the image analysis software. Results: By scanning the same sp

Hydrogen depth profiling by p-p scattering in nominally anhydrous minerals

Hydrogen has been shown to occur as a trace element in many nominally anhydrous minerals. The presence of hydrogen in several of the major minerals in the Earth's mantle has received attention, due to the possibility that these phases provide a significant hydrogen reservoir. Recently an experimental and analytical procedure for hydrogen measurements in thin mineral samples by proton-proton scatte