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Use of holographic laser interferometry to study the diffusion of polymers in gels

The aim of this study was to demonstrate the potential for holographic interferometry to be used for diffusion studies of large molecules in gels. The diffusion and partitioning of BSA (67,000 g/mol) and pullulans (5,900-112,000 g/mol) in agarose gel were investigated. The gel diffusion coefficients obtained for BSA were higher when distilled water was used as a solvent compared to those obtained

Factors associated with cirrhosis development in chronic hepatitis C patients from an area of low prevalence

The aim of this study was to evaluate the importance of different endogenous and exogenous factors associated with cirrhosis development among hepatitis C virus (HCV)-positive individuals from an area of low prevalence. We studied 106 consecutive HCV RNA positive patients who had undergone liver biopsy. Each patient was assessed with special attention to risk factors for hepatitis C infection, ave

The ring nerve of the box jellyfish Tripedalia cystophora

Box jellyfish have the most elaborate sensory system and behavioural repertoire of all cnidarians. Sensory input largely comes from 24 eyes situated on four club-shaped sensory structures, the rhopalia, and behaviour includes obstacle avoidance, light shaft attractance and mating. To process the sensory input and convert it into the appropriate behaviour, the box jellyfish have a central nervous s

Regulation of ADAM12 cell-surface expression by protein kinase C epsilon

The ADAM ( a disintegrin and metalloprotease) family consists of multidomain cell-surface proteins that have a major impact on cell behavior. These transmembrane-anchored proteins are synthesized as proforms that have ( from the N terminus): a prodomain; a metalloprotease, disintegrin-like-, cysteine-rich, epidermal growth factor-like, and transmembrane domain; and a cytoplasmic tail. The 90-kDa m

Ultrafast charge transfer and atomic orbital polarization

The role of orbital polarization for ultrafast charge transfer between an atomic adsorbate and a substrate is explored. Core hole clock spectroscopy with linearly polarized x-ray radiation allows to selectively excite adsorbate resonance states with defined spatial orientation relative to the substrate surface. For c(4x2)S/Ru(0001) the charge transfer times between the sulfur 2s(-1)3p(*+1) antibon

Animal-mediated fertilization in bryophytes – parallel or precursor to insect pollination in angiosperms?

Bryophytes have until now been absent from all hypotheses regarding the origin of insect pollination of seed plants. The discovery that both springtails and mites are able to transfer sperm in mosses makes it possible to suggest a ’Bryophyte precursor hypothesis of plant pollination’ stating that animal-mediated fertilization in mosses and insect pollination in seed plants is historically linked b

Computation of approximate value functions for constrained control problems

The paper discusses an iterative algorithm for computing approximations to the optimal value function for constrained control problems. The algorithm gives an explicit measure on the distance to the optimal value function. A major step in the course of constructing an algorithm for these problems is to choose an efficient parameterization. The choice has several implications. The main obstacl

Purification of plasmid DNA with polymer-salt aqueous two-phase system: Optimization using response surface methodology

An experimental design was used to optimize plasmid purification from an alkaline lysate of Escherichia coli cells using PEG-sodium citrate aqueous two-phase systems (ATIPS), and to evaluate the influence of pH, PEG molecular weight, tie line length, phase volume ratio, and lysate load. To build the mathematical model and minimize the number of experiments for the design parameters, response surfa

Dynamics at the protein-water interface from 17O spin relaxation in deeply supercooled solutions

Most of the decisive molecular events in biology take place at the protein-water interface. The dynamical properties of the hydration layer are therefore of fundamental importance. To characterize the dynamical heterogeneity and rotational activation energy in the hydration layer, we measured the 17O spin relaxation rate in dilute solutions of three proteins in a wide temperature range extending d

Acupuncture facilitates neuromuscular and oculomotor responses to skin incision with no influence on auditory evoked potentials under sevoflurane anaesthesia.

Background: More sevoflurane was recently found to be required to prevent movement in response to surgical incision in anaesthetized patients subjected to electro-acupuncture (EA) than to sham procedures. The present study was designed to compare differences in movement, dilatation of the pupils, divergence of the eye axes and activity of auditory evoked potentials (AEPs) between patients given an

Energy Analysis of Biomass Production and Transportation

Energy efficiency in the production and transportation of different kinds of biomass in Sweden has been analysed, as well as the change in energy efficiency in a transition from fossil-fuel-based to biomass-based systems. Net energy yields under current production conditions were found to be highest for short-rotation forest (Salix) and sugar beet (about 160 to 170 GJ ha-1 year-1), followed by ley

Risk factors of future suicide in suicide attempters - A comparison between suicides and matched survivors

The objective of this study was to find risk factors for suicide by looking for clinical and care/treatment consumption differences between 15 hospitalized suicide attempters, who later committed suicide ("completers''), and 15 suicide attempters who did not ("non-completers''), matched according to sex, age and principal diagnosis. Completers had significantly more often attempted suicide after t