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Energy transduction anchors genes in organelles

The work of mitochondria and chloroplasts is energy transduction in respiration and photosynthesis. The physico-chemical mechanisms of bioenergetics do not directly involve genes and heredity, and furthermore, redox chemistry is intrinsically mutagenic. Thus the small, functional genomes of mitochondria and chloroplasts are an oddity. Although extensively sequenced and catalogued, cytoplasmic geno

Case studies and mathematical models of ecological speciation 3: Ecotype formation in a Swedish snail

Formation of partially reproductively isolated ecotypes in the rough periwinkle, Littorina saxatilis, may be a case of incipient nonallopatric ecological speciation. To better understand the dynamics of ecotype formation, its timescale, driving forces and evolutionary consequences, we developed a spatially explicit, individual-based model incorporating relevant ecological, spatial and mate selecti

The Malmo-Klaipeda WFH twinning programme: a comparative description of the haemophilia cohorts

In 1994, the Malmo-Klaipeda twinning programme was approved by the World Federation of Hemophilia. One of the first steps in the collaboration has been to set up a registry of the haemophilia patients in the Klaipeda area. In order to collect important clinical data the patients have been examined jointly by experts on haemophilia from the two centres. Seventeen out of 25 patients with severe haem

The contribution of genetic variations of aryl hydrocarbon receptor pathway genes to male factor infertility

Objective: To determine whether the polymorphisms in aryl hydrocarbon receptor (AHR), aryl hydrocarbon receptor repressor (AHRR), and aryl hydrocarbon receptor nuclear translocator (ARNT) genes are associated with male factor infertility. Design: An association study. Setting: University research laboratory and andrology clinic. Patient(s): The subjects were infertile Estonian men (n = 112) with a

Toll-like receptor 9 acts at an early stage in host defence against pneumococcal infection

Toll-like receptor 9 (TLR9) induces an inflammatory response by recognition of unmethylated CpG dinucleotides, mainly present in prokaryotic DNA. So far, TLR9-deficient mice have been shown to be more sensitive than wild-type mice to viral, but not to bacterial infections. Here, we show that mice deficient in TLR9 but not in TLR1, TLR2, TLR4 and TLR6 or IL-1R/IL-18R are more susceptible to a respi

Dissolved organic carbon dynamics in the peat-streamwater interface

A series of experiments were conducted to address the fate of dissolved organic carbon (DOC) in the peat - stream interface zone linking a minerotrophic poor fen and an ombrotrophic mire with surrounding stream water in the drainage area of Lake Ortrasket in northern Sweden. Transport and mineralisation of DOC were quantified in peat - stream interface cores in response to variations in pore water

A pneumococcal pilus influences virulence and host inflammatory responses

Streptococcus pneumoniae (pneumococcus) is a major cause of morbidity and mortality world-wide. The initial event in invasive pneumococcal disease is the attachment of encapsulated pneumococci to epithelial cells in the upper respiratory tract. This work provides evidence that initial bacterial adhesion and subsequent ability to cause invasive disease is enhanced by pili, long organelles able to e

Isolation and characterization of neural precursor cells from the Sox1-GFP reporter mouse.

We have made use of a reporter mouse line in which enhanced green fluorescence protein (GFP) is inserted into the Sox1 locus. We show that the GFP reporter is coexpressed with the Sox1 protein as well as with other known markers for neural stem and progenitor cells, and can be used to identify and isolate these cells by fluorescence-activated cell sorting (FACS) from the developing or adult brain

RATE-RATIO ASYMPTOTIC ANALYSIS OF THE INFLUENCE OF ADDITION OF HYDROGEN ON THE STRUCTURE AND MECHANISMS OF EXTINCTION OF NONPREMIXED METHANE FLAMES

Rate-ratio asymptotic analysis is carried out to elucidate the influence of hydrogen on the structure and critical conditions for extinction of nonpremixed methane flames. Steady, axisymmetric, laminar flow of two counterflowing streams toward a stagnation plane is considered. One stream, called the fuel stream is made up of a mixture of methane (CH4) and nitrogen (N-2). The other stream, called t

Substitution or overlap? The relations between geographical and non-spatial proximity dimensions in collaborative innovation projects.

Traditionally, economic geographers stress geographical proximity's positive impact on collaboration processes. However, effects of cognitive, organizational, social and institutional proximity dimensions have been emphasized recently. This paper examines the relations between geography and these non-spatial dimensions by distinguishing two mechanisms: the substitution mechanism, where non-spatial

The Impact of the 1918 Spanish Flu Epidemic on Economic Performance in Sweden - An Investigation into the Consequences of an Extraordinary Mortality Shock

Abstract in UndeterminedWe study the impact of the 1918 influenza pandemic on short- and medium-term economic performance in Sweden. The pandemic was one of the severest and deadliest pandemics in human history, but it has hitherto received only scant attention in the economic literature - despite representing an unparalleled labour supply shock. In this paper, we exploit seemingly exogenous varia

Conventional combination treatment versus biological treatment in methotrexate-refractory early rheumatoid arthritis: 2 year follow-up of the randomised, non-blinded, parallel-group Swefot trial

Background Analysis of the Swedish Farmacotherapy (Swefot) trial at 12 months showed that the addition of an anti-tumour-necrosis-factor agent gave an improved clinical outcome compared with the addition of conventional disease-modifying antirheumatic drugs in patients with methotrexate-refractory early rheumatoid arthritis. Here we report the 2 year follow-up assessment. Methods In this randomise

Cost-effectiveness analysis of ferric carboxymaltose in iron-deficient patients with chronic heart failure in Sweden.

OBJECTIVE: Iron deficiency is a common but treatable comorbidity in chronic heart failure (CHF) that is associated with impaired health-related quality-of-life (HRQoL). This study evaluates the cost-effectiveness of the intravenous iron preparation ferric carboxymaltose (FCM) for the treatment of iron deficiency in CHF from a Swedish healthcare perspective. METHODS: A cost-effectiveness analysi

Amplitude and phase measurements of continuous diffuse fields for structural health monitoring of concrete structures

Structural health monitoring systems for civil structures based on ultrasonic guided waves face the problem of very high attenuation of mechanical waves in concrete. This means that it is difficult to cover large areas with a reasonable number of transducers. Continuous acoustic transmission, as opposed to pulse transmission, enables narrow-band, coherent measurements, which can be used to detect

The protonation status of compound II in myoglobin, studied by a combination of experimental data and quantum chemical calculations: Quantum refinement

Treatment of met-myoglobin (Fe-III) with H2O2 gives rise to ferryl myoglobin, which is closely related to compound II in peroxidases. Experimental studies have given conflicting results for this species. In particular, crystallographic and extended x-ray absorption fine-structure data have shown either a short (similar to170 pm) or a longer (similar to190 pm) Fe-O bond, indicating either a double

Is local distribution of the epiphytic lichen Lobaria pulmonaria limited by dispersal capacity or habitat quality?

By surveying and re-surveying 12 forest sites in southern Sweden for the epiphytic lichen Lobaria pulmonaria with a 9-year interval, and measuring tree-related habitat quality variables, we have investigated whether the local distribution of the lichen is limited by poor dispersal capacity or by habitat quality. Dispersal distances were measured indirectly as the distances between colonised trees

Telomeric sequence diversity within the genus Saccharomyces

Conservation of telomeric DNA repeat sequences has been found across evolutionarily diverse eukaryotes. Here we report on a marked telomeric sequence diversity within the budding yeast genus Saccharomyces. Cloning and sequencing of telomeric repeat units from S. castellii, S. dairensis, S. exiguus and S. kluyveri showed a length variation between 8 and 26 bp, as well as a distinct variation in the

Kinetics of coal desulphurization by Acidianus brierleyi

Acidianus brierleyi was demonstrated to remove pyritic sulphur from coal. A. brierleyi was also found capable of catalyzing the removal of what is normally reported as organic sulphur from coal 171US34. A kinetic analysis was performed by assuming a first order reaction. The first order kinetics allowed a comparison with literature data for Thiobacillus ferrooxidans. Also, formation of jarosite wa