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All-or-none (or something in between) transition of DNA

DNA compaction can be caused by multivalent ions as condensing agents. Both discontinuous (all-or-none) and continuous (pearl-necklace structure) transitions have been observed in experiments as the concentration of the condensing agent was increased. We have investigated the DNA transition by analytical calculations in the infinite-chain limit. A mechanism for pearl-necklace structures could be a

Consequences of Electoral Systems in Africa: A Preliminary Inquiry.

Based on an original data set of elections in Africa, this article addresses the orthodoxy of theoretical hypotheses regarding the effects of electoral systems. While Africanists assume that context make a significant difference, the empirical analysis points to very similar effects of electoral institutions in Africa as in established democracies; regarding reductive effects, effects on the party

Femtosecond noncollinear SFG dynamics in autocorrelator setup at low level of photons.

We report here the characteristics of noncollinear sum frequency generation in nonlinear KDP crystals by ultrashort (80 fsec) IR pulses irradiated by the intense Ti:Sapphire laser and their behavior in single shot auto-crosscorrelator (ACC) configuration. In particular we study the case where one of the beams is very weak. Our aim is develop a procedure to provide delay time signal between light p

Cooperative inhibitory effects of budesonide and formoterol on eosinophil superoxide production stimulated by bronchial epithelial cell conditioned medium

Background: Improved asthma control by combinations of inhaled glucocorticosteroids (GCs) and long-acting beta(2)-agonists (LABAs) includes a reduced frequency and severity of exacerbations. In view of the association of exacerbations with increased airway inflammation, the question has arisen as to whether LABAs are able to complement the known anti- inflammatory activity of GCs. To address this,

Respiratory Tract Deposition of Particles from Biomass Combustion

The respiratory tract deposition of particles from two types of biomass combustion was measured for 10 healthy subjects. The aerosol was extensively characterised. Model calculations of the deposition were made based on the particle properties. The results show that particle water absorption has substantial impact on deposition. The particles from biomass combustion obtained a size in the respirat

NOAA/A AVHRR data for crop productivity estimation in Sweden

Abstract: Studies reported in this paper indicate the Presence of a relation between NOAA/AVHRR data and crop biomass in Sweden. Conclusions so far, however, are that NOAA/AVHRR at the present time can not be successfully applied for operational crop biomass estimation in Sweden. Investigations are now in progress aiming at the practical use of this remotely sensed data for the determination of bi

Effect of tertiary sewage effluent additions on Prymnesium parvum cell toxicity and stable isotope ratios

We investigated the ability of the ichthyotoxic haptophyte Prymnesium parvum to use sewage-originated nutrients applying stable carbon (C) and nitrogen (N) isotope techniques. P. parvum was cultured under N and phosphorus (P) sufficient and deficient conditions in either sewage effluent-based medium or in a nitrate- and phosphate-based control. Cell densities and toxicities were monitored and stab

Solving dimensioning tasks for proportionally fair networks carrying elastic traffic

The paper studies optimal dimensioning problems associated with the notion of “proportional fairness” (PF) considered for packet networks carrying elastic (greedy) traffic, i.e. the traffic streams that can use up, perhaps within certain assumed bounds, any bandwidth that is assigned to them. We give effective, simple and explicit solutions to the introduced optimisation tasks based on the dual op

Chemical composition and morphology of individual aerosol particles from a CARIBIC flight at 10 km altitude between 50 degrees N and 30 degrees S

Analysis of individual particles by analytical electron microscopy as well as quantitative analysis using particle-induced X-ray emission (PIXE) and particle elastic scattering analysis (PESA) were carried out on samples collected from a flight at 10 km altitude between 50 degrees N and 30 degrees S as part of the Civil Aircraft for Regular Investigation of the atmosphere Based on an Instrument Co

Transcription factors involved in the pathogenesis of L-DOPA-induced dyskinesia in a rat model of Parkinson's disease.

L-DOPA-induced dyskinesia (abnormal involuntary movements) is one of the most debilitating complications of chron-ic L-DOPA pharmacotherapy in Parkinson's disease. It is generally agreed that dyskinesia arises as a consequence of pulsatile dopamine-receptor stimulation in the brain, causing downstream changes in genes and proteins. Advance in our understanding of such changes is critically depende

Capture of bacteriocins directly from non-clarified fermentation broth using macroporous monolithic cryogels with phenyl ligands

The bacteriocin, sakacin P was produced by the bacteriocin-producing strain Lactobacillus sakei CCUG 42687 at 20 degrees C without pH control. The bacteriocin was captured directly from the fermentation broth using macroporous octyl- and phenyl-monolith columns. The large size of the interconnected macropores (up to 100 mu m) in the macroporous monolith allowed for direct fermentation broth proces

Synthesis of glutamic acid analogs as potent inhibitors of leukotriene A(4) hydrolase

Leukotriene B-4 (LTB4) is a potent pro-inflammatory mediator that has been implicated in the pathogenesis of multiple diseases, including psoriasis, inflammatory bowel disease, multiple sclerosis and asthma. As a method to decrease the level of LTB4 and possibly identify novel treatments, inhibitors of the LTB4 biosynthetic enzyme, leukotriene A(4) hydrolase (LTA(4)-h), have been explored. Here we

Neoglycoconjugates of mannan with bovine serum albumin and their interaction with lectin concanavalin A

Neoglycoconjugates were prepared from mannan isolated from yeast Saccharomyces cerevisiae and activated by periodate oxidation to create aldehyde groups. Various degrees of oxidation introduced 11-28 aldehyde groups per mannan molecule and simultaneously resulted in a molar mass decrease from 46 to 44.5-31 kDa. The activated mannans were subsequently conjugated with bovine serum albumin forming ne

Clusterin in cerebrospinal fluid: analysis of carbohydrates and quantification of native and glycosylated forms

Clusterin is suggested to be involved in the pathogenesis of Alzheimer's disease. Clusterin expression is increased in brain tissue in affected regions of Alzheimer patients, and intense clusterin staining is found in both senile plaques and in neuronal and glia cells. In contrast, the cerebrospinal fluid level of clusterin in Alzheimer patients has, thus far, been found unchanged. Clusterin is a

Bio-ethanol - the fuel of tomorrow from the residues of today

The increased concern for the security of the oil supply and the negative impact of fossil fuels on the environment, particularly greenhouse gas emissions, has put pressure on society to find renewable fuel alternatives. The most common renewable fuel today is ethanol produced from sugar or grain (starch); however, this raw material base will not be sufficient. Consequently, future large-scale use

Do they know what they are doing? Risk perceptions and smoking behaviour among Swedish teenagers

Cross-sectional survey data on Swedish adolescents aged 12 - 18 was used to analyse perceived risks of smoking-related lung cancer, the determinants of these risk perceptions, and how these perceptions related to smoking behaviour. Three major conclusions were drawn: ( 1) that both smokers and non-smokers overestimated the risks of lung cancer, ( 2) that these risk perceptions fell substantially w

Sustained attention analyzed by a new computerized dark adaptometer

A new computerized dark adaptometer was developed achieving a 50% reduction of examination time. Functions were implemented for the recording of sustained attention (ie, the capacity to maintain focus and alertness over time (vigilance)). Eighteen healthy subjects were tested three times each on different days. All tests were analyzed for parameters analogous to measurements derived from continuou

Relationship between pressure-volume curve and markers for collagen turn-over in early acute respiratory distress syndrome

OBJECTIVE: In acute respiratory distress syndrome, the relationships between changes in the elastic behavior of the respiratory system and biological markers of extra-cellular matrix or surfactant turn-over could give some insights into its pathophysiological determinants. DESIGN AND MEASUREMENTS: In 17 patients with acute respiratory distress syndrome, we assessed the relationship between chord c