A tree t-spanner T of a graph G is a spanning tree of G whose max-stretch is t, i.e., the distance between any two vertices in T is at most t times their distance in G. If G has a tree t-spanner but not a tree (t−1)-spanner, then G is said to have max-stretch of t. In this paper, we study the Max-Stretch Reduction Problem: for an unweighted graph G=(V,E), find a set of edges not in E originally wh

Recent studies have provided evidence for a major role of urothelially released ATP acting on a subpopulation of pelvic afferent nerves in mechano-afferent transduction in the bladder. We investigated whether desensitization of capsaicin-sensitive nerve fibres by systemic resiniferatoxin (RTX)-pretreatment can counteract the detrusor over-activity induced by intravesical capsaicin, acetic acid or

We studied the population structure of a high arctic breeding wader bird species, the White-rumped Sandpiper Calidris fuscicollis. Breeding adults, chicks and juveniles were sampled at seven localities throughout the species' breeding range in arctic Canada in 1999. The mitochondrial control region was analysed by DNA sequencing, feathers were analysed for carbon isotope ratios (C-13/C-12) by isot

A connection between Alzheimer's disease (AD) and endothelium pathology has been inferred from measured decreases in both blood flow and metabolism in the parietal and temporal cortex. However, it is not known whether these alterations are seen in normal aging. We performed regional cerebral blood flow (rCBF) measurements in 22 AD patients and in 44 non-demented subjects during a simple test of in

Here we investigate ERα and ERβ expression and regulation in vascular smooth muscle cells from mouse aorta. Immunocytochemistry showed nuclear staining for both ERα and ERβ. Double stainings revealed co-expression of ERα and ERβ in vascular smooth muscle cells. ERα (66 kDa) and ERβ (54 kDa) expression determined by Western blotting was unchanged within 7 h after inhibition of protein synthesis wit

We here study the interactions of a polyamide with large DNA, and compare to those of minor groove binder distamycin (DST), including high ligand/DNA binding ratios. Specific as well as nonspecific binding is probed using polarized-light spectroscopy combined with singular value decomposition analysis. Circular and linear dichroism data confirm binding geometries consistent with minor groove bindi

Seven-transmembrane G-protein-coupled receptors play a central role in physiology by facilitating cell communication through recognition of a wide range of ligands. Even more important, they represent important drug targets. Unfortunately, for many of these receptors the endogenous ligands, and hence their functions, remain to be identified. These receptors are referred to as "orphan" receptors. A

OBJECTIVE: A low Sense of Coherence (SOC) is a concept related to a feeling of ill health. Not much is known about possible relationships between SOC and biological factors. SETTING: Population-based study of middle-aged women. SUBJECTS AND METHODS: Four-hundred-and-fifty women participated as a subgroup of a larger study of cardiovascular risk factor screening. A self-administered questionnaire w

A rapidly implemented qualitative study was conducted to investigate the perceptions of women about abortion in Egypt using in-depth interviews with hospitalised patients and focus group discussions with family planning clients and non-contracepting women. The most salient issue confronting the patients (whether the abortion had been spontaneous or induced) was their physical survival. The necessi

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)

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

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

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.

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

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

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 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

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