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Chlamydia trachomatis infection and persistence of human papillomavirus.

Human papillomavirus (HPV) persistence is the major cause of cervical cancer, but most HPV infections will not persist and risk factors for HPV persistence are not well known. Chlamydia (C.) trachomatis infection seems to also be associated with cervical cancer. We investigated whether C. trachomatis infection is a risk factor for HPV persistence. In a cohort of 12,527 women participating in a pop

Mechanism of surfactant effect in enzymatic hydrolysis of lignocellulose

Lignocellulose is a potential substrate for ethanol production. However, high cellulose conversion requires high enzyme loading, which makes the process less economically feasible. Addition of surfactants to enzymatic hydrolysis of lignocellulose increases the conversion of cellulose into soluble sugars. The mechanism is not known for the increase of lignocellulose hydrolysis by surfactant additio

Estimating carbon emissions from African wildfires

We developed a technique for studying seasonal and interannual variation in pyrogenic carbon emissions from Africa using a modelling approach that scales burned area estimates from L3JRC, a map recently generated from remote sensing of burn scars instead of active fires. Carbon fluxes were calculated by the novel fire model SPITFIRE embedded within the dynamic vegetation model framework LPJ-GUESS,

Patterns of morphometric variation and a new supraspecific classification of apomictic taxa of Hieracium (Asteraceae) from Denmark and southern Sweden

Patterns of variation among all micro-species of Hieracium sect. Hieracium and H. sect. Vulgata known from Denmark and southern Sweden are investigated. Forty-three, possibly independent morphological characters are used. Significant correlations were revealed among the majority of the characters. Multivariate analyses did not reveal any discontinuities in the variation or any discrete groups of s

Effect of a matrix metalloproteinase activity and TNF-alpha converting enzyme inhibitor on intra-abdominal adhesions.

BACKGROUND: Formation of intra-abdominal adhesions depends, in part, on the activity of serine proteinases. Matrix metalloproteinases (MMP) are required for epithelialization of skin wounds but their involvement in mesothelialization of peritoneal wounds and in adhesion pathogenesis is not known. Early tumor necrosis factor-alpha (TNF-alpha) levels have been proposed to reflect propensity to adhes

High carrier mobility in low band gap polymer-based field-effect transistors

A conjugated polymer with a low band gap of 1.21 eV, i.e., absorbing infrared light, is demonstrated as active material in field-effect transistors (FETs). The material consists of alternating fluorene units and low band gap segments with electron donor-acceptor-donor units composed of two electron-donating thiophene rings attached on both sides of a thiadiazolo-quinoxaline electron-acceptor group

HYBRIDLAB (version 1.0): a program for generating simulated hybrids from population samples

We present the computer program HYBRIDLAB 1.0 for simulating intraspecific hybrids from population samples of nuclear genetic markers such as microsatellites, allozymes or SNPs ( single nucleotide polymorphisms). The program generates a user-specified number of multilocus F1 hybrid genotypes between any pair of potentially hybridizing populations included in a standard input-file of multilocus gen

Skeletal muscle telomere length is not impaired in healthy physically active old women and men

We have previously shown that the number of satellite cells is lower in old than young men and women. The aim of this study was to further explore the effects of aging on the regenerative potential of skeletal muscle in 16 young and 26 old men and women with comparable physical activity level (young, 25 +/- 4 years; old, 75 +/- 4 years). Mean and minimum telomere lengths were determined using Sout

Application of advanced laser diagnostics for the investigation of the ionization sensor signal in a combustion bomb

The ionization sensor is an electrical probe for diagnostics in internal combustion engines. Laser-induced fluorescence (LIF) imaging of fuel, hydroxyl (OH), and nitric oxide (NO) distributions has been employed to extend our knowledge about the governing processes leading to its signal. By monitoring the flame propagation in quiescent and turbulent mixtures, the cycle-to-cycle variations in the e

Linear water waves with vorticity: rotational features and particle paths

Steady linear gravity waves of small amplitude travelling on a current of constant vorticity are found. For negative vorticity we show the appearance of internal waves and vortices, wherein the particle trajectories are not any more closed ellipses. For positive vorticity the situation resembles that of Stokes waves, but for large vorticity the trajectories are affected.

Functional and phenotypical comparison of myofibroblasts derived from biopsies and bronchoalveolar lavage in mild asthma and scleroderma

Background: Activated fibroblasts, which have previously been obtained from bronchoalveolar lavage fluid (BALF), are proposed to be important cells in the fibrotic processes of asthma and scleroderma (SSc). We have studied the motility for BALF derived fibroblasts in patients with SSc that may explain the presence of these cells in the airway lumen. Furthermore, we have compared phenotypic alterat

Minimum weight pseudo-triangulations

We consider the problem of computing a minimum weight pseudo-triangulation of a set S of n points in the plane. We first present an O(nlogn)-time algorithm that produces a pseudo-triangulation of weight O(wt(M(S))logn) which is shown to be asymptotically worst-case optimal, i.e., there exists a point set S for which every pseudo-triangulation has weight Omega(wt(M(S))logn), where wt(M(S)) is the w

cGMP-independent inotropic effects of nitric oxide and peroxynitrite donors: potential role for nitrosylation

Nitric oxide (NO) has concentration-dependent biphasic myocardial contractile effects. We tested the hypothesis, in isolated rat hearts, that NO cardiostimulation is primarily non-cGMP dependent. Infusion of 3-morpholinosydnonimine (SIN-1, 10(-5) M), which may participate in S-nitrosylation (S-NO) via peroxynitrite formation, increased the rate of left ventricular pressure rise (+dP/dt; 19 +/- 4%,

Effect of pharmaceutically acceptable glycols on the stability of the liquid crystalline gels formed by poloxamer 407 in water

The ability of poly(ethylene oxide)-poly(propylene oxide)-poly (ethylene oxide) (PEO-PPO-PEO) block copolymers (Poloxamers) to form "gels" (lyotropic liquid crystalline structures) in water is of interest to pharmaceutical applications. In such applications the presence of polar organic solvents is often desirable or required. The effect of such solvents on the stability of lyotropic liquid crysta

Citrate synthase from Thermus aquaticus: a thermostable bacterial enzyme with a five-membered inter-subunit ionic network.

A bacterial thermostable citrate synthase has been analyzed to investigate the structural basis of its thermostability, and to compare such features with those previously identified in archaeal citrate synthases. The gene encoding the citrate synthase from Thermus aquaticus was identified from a gene library by screening with a PCR fragment amplified from genomic DNA using a primer based on the de

Heterotrophic bacterial and viral dynamics in Arctic freshwaters: results from a field study and nutrient-temperature manipulation experiments

Heterotrophic bacterial and viral concentrations (range, 0.7 x 10(4) to 206.2 x 10(4) ml(-1) and 0.05 x 10(6) to 128.9 x 10(6) ml(-1), respectively) were determined in several Arctic freshwater environments, including lakes and glacial ecosystems (78.55 degrees N, 11.56 degrees E). Our bacteria and virus results mirrored trends seen in temperate lakes, with an average virus-to-bacteria ratio (VBR)

Altered swallowing function in elderly patients without dysphagia: radiologic findings in 56 cases

Swallowing disorder is an increasing problem in our aging population. A majority of these patients have a functional abnormality of the oral, pharyngeal, and/or esophageal stage of swallowing. However, what constitutes normalcy is not well understood, and baseline swallowing in elderly persons without dysphagia has not been adequately described. We therefore evaluated 56 persons with a mean age of