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Human activity often causes a decline in the local density of plant populations. Below some critical lower density, populations may suffer a progressive decline in reproductive success because of the difficulties associated with finding suitable mates. Therefore, to conserve endangered plant species it is necessary to understand in greater detail how changes in population density affect different

Dendritic cells (DCIs) possess a potent ability to modulate and activate specific T-cell responses to allergens, which play a pivotal role in allergic inflammation by secreting cytokines and other mediators. However, the molecular mechanisms by which allergen-challenged DCs regulate specific T-cell responses are still not well characterized. This study aims at elucidating the molecular mechanisms

The robustness of a dual-beam, optical null, Fourier-transform near-infrared (FTNIR) spectrometer was investigated by means of online, near-infrared measurements and predictions of urea concentrations in spent dialysate during hemodialysis treatment. Simple multivariate calibration using a few factors based on a small number of prepared samples provided stable and accurate predictions over a perio

Trends in energy intensities for 31 countries are evaluated, over the period from 1950 to 1988, using a purchasing power parity-based GDP measure and United Nations energy statistics. With non-commercial energy included, the energy intensities of low income countries are similar to those of high income countries. Energy intensities have decreased for 15 out of the 31 countries studied. The analysi

This article describes a study where laboratory and theoretical work on the fundamental hygro-mechanical behaviour of wood is applied on convective drying of sawn timber. A material model describing the behaviour of wood during drying is used to simulate drying stresses in timber. Cross-sections containing heartwood, sapwood and a combination of both are studied. Simulations are compared with meas

A new relationship between the roughness height and the main hydrodynamic and sediment parameters for plane beds under oscillatory conditions is presented. In order to derive such a relationship, a large data base encompassing plane-bed experiments was compiled from previous investigations and analyzed. Different methods to estimate the roughness height were investigated. Comparisons between the d

The Southern Ocean is split into several biogeographical provinces between convergence zones that separate watermasses of different temperatures. Recent molecular phylogenies have uncovered a strong phylogeographic structure among rockhopper penguin populations, Eudyptes chrysocome sensu lato, from different biogeographical provinces. These studies suggested a reclassification as three species in

Clear cell sarcoma (CCS) is a rare malignant soft tissue tumor particularly associated with tendons and aponeuroses. The cytogenetic hallmark is the translocation t(12;22)(q13;q12) resulting in a chimeric EWS/ATF1 gene in which the 3'-terminal part of EWS at 22q is replaced by the 3'-terminal part of ATF1 at 12q. To date, only 13 cases of CCS have been analyzed for fusion genes at the transcriptio

Streptomycetes grow by cell wall extension at hyphal tips. The molecular basis for such polar growth in prokaryotes is largely unknown. It is reported here that DivIVA SC , the Streptomyces coelicolor homologue of the Bacillus subtilis protein DivIVA, is essential and directly involved in hyphal tip growth and morphogenesis. A DivIVA SC -EGFP hybrid was distinctively localized to hyphal tips and l

To study which individual characteristics and environmental factors correlate with fear of moving outdoors and whether fear of moving outdoors predicts development of mobility limitation. Observational prospective cohort study and cross-sectional analyses. Community and research center. Seven hundred twenty-seven community-living people aged 75 to 81 were interviewed at baseline, of whom 314 took

HIV particles that use the chemokine receptor CXCR4 as a coreceptor for entry into cells (X4-HIV) inefficiently transmit infection across mucosal surfaces [1], despite their presence in seminal fluid and mucosal secretions from infected individuals [2] [3] [4]. In addition, although intestinal lymphocytes are susceptible to infection with either X4-HIV particles or particles that use the chemokine

The use of valproic acid during human pregnancy increases the risk of hypospadias in the offspring. Rats exposed in utero to valproic acid did not develop hypospadias and even had a slightly increased anogenital distance in males 3-4 days after birth. A classical antiandrogenic drug, flutamide, caused hypospadias as well as a reduction of the anogenital distance in males. At the age of 3 months, r

Despite the growing evidence that elevated total homocysteine (tHcy) in plasma is a cardiovascular risk factor, the mechanism underlying the vascular injury is still unknown. Studies are difficult due to the fact that little is known about the formation of different homocysteine species in vivo. In the present study we have investigated the different fractions of tHcy in 21 patients with acute cor

At evaluation of contact dermatitis caused by solid material, patch testing is usually performed with the material as such and with extracts of it. In this study, optimization of the extraction technique monitored by quantitative HPLC analysis of the extracted haptens is described for mercaptobenzothiazole derivatives. Several solvents with different properties are included. Acetone has traditiona

The relationships among cellular nutrient status, environmental conditions (temperature and nutrient availability), and cyst production were studied in batch cultures of three cold-water dinoflagellates (Scrippsiella hangoei, Gymnodinium corollarium, and Woloszynskia halophila) isolated from the Baltic Sea. We tested the effect of increasing temperature while providing nutrient-replete conditions

The theory of sexual conflict predicts that sexual coevolution will be very dynamic, with in principle perpetual evolutionary arms races and chases. These arms races are expected to stop once the costs of conflict adaptations become too high. We argue that this prediction is contingent on specific assumptions about the sexual interaction and the adaptations involved in the arms race. More generall

During ultrafiltration (UF), the driving force along the membrane is diminished due to concentration increase and frictional pressure drop. In most applications of ultrafiltration the influence of the frictional pressure drop is negligible. However, when treating concentrated, viscous liquids the frictional pressure drop can reduce the transmembrane pressure (TMP) significantly. The influence of c