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Binding effects in multivalent Gibbs-Donnan equilibrium

The classical Gibbs-Donnan equilibrium describes excess osmotic pressure associated with confined colloidal charges embedded in an electrolyte solution. In this work, we extend this approach to describe the influence of multivalent ion binding on the equilibrium force acting on a charged rod translocating between two compartments, thereby mimicking ionic effects on force balance during in vitro DN

Calibrated pollen accumulation rates as a basis for quantitative tree biomass reconstructions

Recent investigations show that the pollen accumulation rate (PAR) of the common tree taxa is directly related to the biomass and, by inference, to the population size of the taxa around the study site. Fossil PAR records preserved in lakes provide therefore a potential proxy for quantitative biomass and population reconstructions. We use the high-resolution PAR records obtained from two accuratel

Common variants in LSP1, 2q35 and 8q24 and breast cancer risk for BRCA1 and BRCA2 mutation carriers

Genome-wide association studies of breast cancer have identified multiple single nucleotide polymorphisms (SNPs) that are associated with increased breast cancer risks in the general population. In a previous study, we demonstrated that the minor alleles at three of these SNPs, in FGFR2, TNRC9 and MAP3K1, also confer increased risks of breast cancer for BRCA1 or BRCA2 mutation carriers. Three addi

Implications of the view of programs as formal systems

The prevailing view of software development as the production of program systems is abandoned in favor of software development as theory building. This suggests that software development properly should be regarded as a deductive activity following the same methodology as is used in all deductive sciences. Programming is merely the description process in the activity of building theories about thi

Imaging Ultrafast Demagnetization Dynamics after a Spatially Localized Optical Excitation

Ultrashort, coherent x-ray pulses of a free-electron laser are used to holographically image the magnetization dynamics within a magnetic domain pattern after creation of a localized excitation via an optical standing wave. We observe a spatially confined reduction of the magnetization within a couple of hundred femtoseconds followed by its slower recovery. Additionally, the experimental results s

Force chains in monodisperse spherical particle assemblies: Three-dimensional measurements using neutrons.

The full triaxial stress state within individual particles in a monodisperse spherical granular assembly has been measured. This was made possible by neutron imaging and computed tomography combined with neutron diffraction strain measurement techniques and associated stress reconstruction. The assembly in question consists of 549 precision steel ball bearings under an applied axial load of 85 MPa

Stress-related challenges in pentose fermentation to ethanol by the yeast Saccharomyces cerevisiae.

Conversion of agricultural residues, energy crops and forest residues into bioethanol requires hydrolysis of the biomass and fermentation of the released sugars. During the hydrolysis of the hemicellulose fraction, substantial amounts of pentose sugars, in particular xylose, are released. Fermentation of these pentose sugars to ethanol by engineered Saccharomyces cerevisiae under industrial proces

Cost of multiple sclerosis in the Czech Republic: The COMS study

Background: Information about cost of multiple sclerosis (MS) is available from a number of European countries, but no data from the Czech Republic have been published so far. Objective: The objective of this study was to establish the cost of MS in the Czech Republic, overall and by level of disease severity. Methods: Data on demographics, disease history, resource consumption and production loss

An integrative genomics screen uncovers ncRNA T-UCR functions in neuroblastoma tumours

Different classes of non-coding RNAs, including microRNAs, have recently been implicated in the process of tumourigenesis. In this study, we examined the expression and putative functions of a novel class of non-coding RNAs known as transcribed ultraconserved regions (T-UCRs) in neuroblastoma. Genome-wide expression pro. ling revealed correlations between specific T-UCR expression levels and impor

Diagnostic and prognostic significance of proteinuria selectivity index in glomerular diseases

The proteinuria selectivity index (SI) describes changes of the glomerular permeability for macromolecules. In the present study, we examine the implications of SI as a diagnostic (199 patients) and a prognostic (49 patients) marker in glomerular diseases. Using SI based on alpha(2)-macroglobulin (alpha(2)-M-SI) or on IgM (IgM-SI) we found that minimal change nephropathy could be discriminated by

Genome-based identification and analysis of collagen-related structural motifs in bacterial and viral proteins.

Collagens are extended trimeric proteins composed of the repetitive sequence glycine-X-Y. A (c) under bar ollagen- related (S) under bar tructural (m) under bar otif (CSM) containing glycine-X-Y repeats is also found in numerous proteins often referred to as collagen-like proteins. Little is known about CSMs in bacteria and viruses, but the occurrence of such motifs has recently been demonstrated.

Multiple HIV-1 introductions into the Swedish intravenous drug user population

In 2001, an increase of HIV-1 diagnoses among intravenous drug users (IVDU) was reported in Sweden. In nearby countries, Finland, Russia and the Baltic states, recent outbreaks had been described. Since there was a concern that these outbreaks would carry over to Sweden a study was initiated to determine the factors leading to the Swedish increase of HIV-1 diagnosed IVDUs. HIV-1 env V3 sequences w

Concise Review: Hematopoietic Stem Cell Aging and the Prospects for Rejuvenation.

Because of the continuous increases in lifetime expectancy, the incidence of age-related diseases will, unless counteracted, represent an increasing problem at both the individual and socioeconomic levels. Studies on the processes of blood cell formation have revealed several shortcomings as a consequence of chronological age. They include a reduced ability to mount adaptive immune responses and a

International Organization of Physical Therapy in Mental Health consensus on physical activity within multidisciplinary rehabilitation programmes for minimising cardio-metabolic risk in patients with schizophrenia

Purpose: The excess cardiovascular morbidity associated with schizophrenia is attributed to an interplay between behavioural (physical inactivity, unhealthy diet, substance abuse), genetic and illness related factors, as well as the effects of antipsychotic treatment. Patients have limited access to physical healthcare with less opportunity for cardiovascular risk prevention and treatment programm

Trophic interactions in changing landscapes: responses of soil food webs

Soil communities in landscapes that are rapidly changing due to a range of anthropogenic processes can be regarded as highly transient systems where interactions between competing species or trophic levels may be seriously disrupted. In disturbed communities dispersal in space and time has a role in ensuring continuity of community function. Stable communities, in undisturbed systems, are more dep

Free volume and interstitial mesopores in silica filled poly(I-trimethylsilyl-l-propyne) nanocomposites

The free volume sizes and interstitial mesopore sizes in poly(l-trimethylsilyl-l-propyne) (PTMSP)/silica nanocomposites and the correlation between nitrogen permeability and cavity sizes were studied with positron annihilation lifetime spectroscopy (PALS) at filler concentrations between 0 and 50 wt %. A bimodal free volume distribution was observed for PTMSP, and the size of the larger free volum

Modulation of chemoselectivity by protein additives. Remarkable effects in the oxidation of hyperforin

Protein additives have a dramatic effect on the H2O2 oxidation of hyperforin, either protecting the enolized phloroglucinol core from oxidation (human albumin) or promoting (HRP and ovalbumin) reaction pathways derived from the intermediacy of the enollactone 4, a minor component of the oxidation mixture in the absence of protein additives. To rationalize the exquisite specificity of several steps