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Hydrogels from a water-soluble zwitterionic polythiophene: Dynamics under pH change and biomolecular interactions observed using quartz crystal microbalance with dissipation monitoring

The water-soluble zwitterionic polythiophene, poly(3-((S)-5-amino-5-carboxyl-3-oxapentyl)-2,5-thiophene) hydrochloride (POWT), is a conjugated polyelectrolyte (CPE) with properties well suited for biochip applications. CPEs readily form hydrogels when exposed to water-based buffer solutions or biomolecule solutions. In this work, we used in situ quartz crystal microbalance with dissipation (QCM-D)

Tuberculosis in Bissau: incidence and risk factors in an urban community in sub-Saharan Africa

Background Despite the long history of tuberculosis (TB) research, population-based studies from developing countries are rare. Methods In a prospective community study in Bissau, the capital of Guinea-Bissau, we assessed the impact of demographic, socioeconomic and cultural risk factors on active TB. A surveillance system in four districts of the capital identified 247 adult (greater than or equa

Bandwidth considerations for a CALLUM transmitter architecture

This article present an investigation of the combined analog locked loop universal modulator (CALLUM) linear transmitter architecture. A simple approximate formula is derived, linking the instantaneous frequency of the CALLUM signals to the modulation depth of the information signal. Further, the effect of the frequency mismatch between the VCOs present in the CALLUM architecture is examined, and

Visual pigments: Trading noise for fast recovery

Spontaneous activation of rhodopsin without light absorption occurs at a much lower rate in rod photoreceptors and insect rhabdoms than in cones. The difference lies in the pigment molecules themselves, and has implications for the design of visual photoreceptors.

Dislocation-based modelling of the growth of a micro structurally short crack by single shear due to fatigue loading

The growth of a short edge crack, located within one grain in a bcc crystal and subjected to cyclic loading, is modelled using a dislocation formulation. The external boundary including the crack itself is built from dislocation dipole elements and the plasticity is represented by discrete dislocations moving along preferred slip planes. The crack propagates by single shear due to emission and ann

Lowering the dose of antenatal steroids: The effects of a single course of betamethasone on somatic growth and brain cell proliferation in the rat

We investigated the effects of a single course of antenatal betamethasone on neonatal somatic and brain development. On day 20 of gestation, pregnant rats were injected with either with 170 mu g kg(-1) body weight of betamethasone ("clinically-equivalent dose," equivalent to 12 mg twice, 24 hours apart) or half this dose or vehicle. Pups (8-11 animals per experimental group per time-point per gend

On-line Detection of Acetate Formation in Escherichia coli Cultures using Dissolved Oxygen Responses to Feed Transients

Recombinant protein production in Escherichia coli can be significantly reduced by acetate accumulation. It is demonstrated that acetate production can be detected on-line with a standard dissolved oxygen sensor by superimposing short pulses to the substrate feed rate. Assuming that acetate formation is linked to a respiratory limitation, a model for dissolved oxygen responses to transients in sub

Molecular phylogeny of the subfamilies in Geometridae (Geometroidea: Lepidoptera)

Molecular sequence data from three gene fragments were used to examine critically a provisional phylogenetic classification based on morphological characters of the Geometridae, one of the most species-rich families of moths. The sister group relationship between Geometridae and Drepanidae gained further support from the molecular analysis, which was based on the ND1 mitochondrial gene and the fir

Public Transport in Dar-es-Salaam, Tanzania.

The study which was conducted from January 2003 to December 2004 was to yield a specific knowledge about the technical and institutional problems, challenges and opportunities in planning for sustainable urban transportation. Before reaching this stage, it was necessary to get a clear picture the problem, and this showed that the performance of public transportation in Dar-es-Salaam in terms of so

Speed and context: the effect of a sentence prime on naming speed in children with language impairment

Nineteen pre-school children with language impairment participated in a computerized naming task. The naming procedure involved two conditions, one unprimed where the child had to name a colour picture appearing on the screen as fast as possible and one primed where the picture was preceded by an uncompleted sentence. Response times were significantly shorter in the primed condition compared to th

FLT3 receptor and ligand are dispensable for maintenance and posttransplantation expansion of mouse hematopoietic stem cells

Originally cloned from hematopoietic stem cell (HSC) populations and its ligand being extensively used to promote ex vivo HSC expansion, the FMS-like tyrosine kinase 3 (FLT3; also called FLK2) receptor and its ligand (FL) were expected to emerge as an important physiologic regulator of HSC maintenance and expansion. However, the role of FLT3 receptor and ligand in HSC regulation remains unclear an

Consumption and portion sizes of tree nuts, peanuts and seeds in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohorts from 10 European countries

Tree nuts, peanuts and seeds are nutrient dense foods whose intake has been shown to be associated with reduced risk of some chronic diseases. They are regularly consumed in European diets either as whole, in spreads or from hidden sources (e.g. commercial products). However, little is known about their intake profiles or differences in consumption between European countries or geographic regions.

Self-image, self-values and interpersonal values among newly graduated nurses

This longitudinal study (1994-1996) used the Gordon Personality Inventory to measure nursing students' self-image (Gordon A), self-values (Gordon B) and interpersonal values (Gordon C). It was performed with students from three colleges of health in the south of Sweden: Jonkoping (n = 54), Vaxjo (n = 24) and Kristianstad (n = 38). The null hypothesis of the study was that the new academic three-ye

Correlational selection and the evolution of genomic architecture

We review and discuss the importance of correlational selection (selection for optimal character combinations) in natural populations. If two or more traits subject to multivariate selection are heritable, correlational selection builds favourable genetic correlations through the formation of linkage disequilibrium at underlying loci governing the traits. However, linkage disequilibria built up by

Sensory nerve desensitization by resiniferatoxin improves glucose tolerance and increases insulin secretion in Zucker diabetic fatty rats and is associated with reduced plasma activity of dipeptidyl peptidase IV

Sensory nerve desensitization by capsaicin has been shown to improve the diabetic condition in Zucker Diabetic Fatty rats. However, administration of capsaicin to adult rats is associated with an increased mortality. Therefore, in this experiment, we examined the influence of resiniferatoxin, a tolerable analogue of capsaicin suitable for in vivo use, on the diabetic condition of Zucker Diabetic F

Evaluation of an educational "toolbox" for improving nursing staff competence and psychosocial work environment in elderly care: Results of a prospective, non-randomized controlled intervention

Background: Lack of professional development opportunities among nursing staff is a major concern in elderly care and has been associated with work dissatisfaction and staff turnover. There is a lack of prospective, controlled studies evaluating the effects of educational interventions on nursing competence and work satisfaction. Objectives: The aim of this study was to evaluate the possible effec