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Multiple stressors on biotic interactions: how climate change and alien species interact to affect pollination

Global change may substantially affect biodiversity and ecosystem functioning but little is known about its effects on essential biotic interactions. Since different environmental drivers rarely act in isolation it is important to consider interactive effects. Here, we focus on how two key drivers of anthropogenic environmental change, climate change and the introduction of alien species, affect p

Dual endothelin receptor blockade with tezosentan markedly attenuates hypoxia induced pulmonary vasoconstriction in a porcine model.

Aim: Our aim was to test the hypothesis that dual endothelin receptor blockade with tezosentan attenuates hypoxia induced pulmonary vasoconstriction. Methods: 14 anaesthetised, ventilated pigs, with a mean±SEM weight of 30,5±0,6 kg, were studied, in normoxia (FiO(2) â0,21) and with tezosentan (5mg·kg(-1) ) infusion during (n=7) or before (n=7) hypoxia (FiO(2) ∼0,10). Results: Compared to normoxia,

Tungsten spectroscopy in the EUV range observed at a high-temperature superconducting electron-beam ion trap

We have recorded extreme ultraviolet spectra from W11+ to W15+ ions using a flat-field spectrometer installed at the Shanghai high-temperature superconducting electron-beam ion trap. The spectra were recorded at beam energies ranging between 200 and 400 eV and showed spectral lines and transition arrays in the 170-260 angstrom region. The charge states and spectra transitions were identified by co

Women’s Education, Empowerment, and Contraceptive Use in Sub-Saharan Africa: Findings from Recent Demographic and Health Surveys

Fertility remains higher and contraceptive levels are substantially lower in Sub-Saharan Africa than elsewhere in the developing world. In this paper we use information on individuals and couples provided in recent Demographic and Health Surveys (DHS, fifth wave) undertaken in Ghana, Kenya, Madagascar, and Zambia. We use bivariate and multivariate techniques to examine the determinants of contrace

On the biologically effective dose (BED)-using convolution for calculating the effects of repair: II. Numerical considerations.

We have previously shown analytically that the biologically effective dose (BED), including effects of repair during irradiation and of incomplete repair between fractions, can be formulated using a convolution between the absorbed dose rate function and the function describing repair. In this work, a discrete formalism is derived along with its implementation via the fast Fourier transform. The i

Finite volume effects for nucleon and heavy meson masses

We apply the resummed version of the Luscher formula to analyze finite volume corrections to the mass of the nucleon and of heavy mesons. We show that by applying the subthreshold expansion of the scattering amplitudes one can express the finite volume corrections in terms of only a few physical observables and the size of the box. In the case of the nucleon, the available information about the qu

Coiled coil cytoskeletons collaborate in polar growth of Streptomyces.

Streptomyces is a multicellular mycelial bacterium, which exhibits pronounced cell polarity and grows by extension of the hyphal tips. Similarly to other polarly growing walled cells, such as filamentous fungi or pollen tubes, Streptomyces hyphae face an intrinsic problem: addition of new cell wall material causes structural weakness of the elongating tip. Cellular strategies employed by walled ce

Lattice Free Stochastic Dynamic

We introduce a lattice-free hard sphere exclusion stochastic process. The resulting stochastic rates are distance based instead of cell based. The corresponding Markov chain build for this many particle system is updated using an adaptation of the kinetic Monte Carlo method. It becomes quickly apparent that due to the lattice-free environment, and because of that alone, the dynamics behave differe

Continuous distal migration and internal rotation of the C-stem prosthesis without any adverse clinical effects: an RSA study of 33 primary total hip arthroplasties followed for up to ten years.

In 2005, we demonstrated that the polished triple-tapered C-stem at two years had migrated distally and rotated internally. From that series, 33 patients have now been followed radiologically, clinically and by radiostereometric analysis (RSA) for up to ten years. The distal migration within the cement mantle had continued and reached a mean of 2 mm (0.5 to 4.0) at ten years. Internal rotation, al

Extra-articular rheumatoid arthritis.

PURPOSE OF REVIEW: To discuss recent findings on the epidemiology and pathogenesis of extra-articular manifestations in rheumatoid arthritis (RA), and provide an update on the literature on treatment of patients with extra-articular RA (ExRA) manifestations. RECENT FINDINGS: ExRA is associated with increased comorbidity and mortality. Several surveys suggest that some ExRA manifestations, in parti

Habitat specialization through germination cueing: a comparative study of herbs from forests and open habitats.

Background and AimsThis study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently accompanied by specialization in their regeneration niche; and (2) species are thereb

Neuronal and Glial Alterations in Complex Long-Term Rhegmatogenous Retinal Detachment.

Purpose: To explore neuronal and glial alterations in eyes with complex long-term rhegmatogenous retinal detachment (RRD). Methods: Morphological analysis was performed on eight retinal specimens derived from patients treated with peripheral retinectomy for RRD complicated by retinal shortening or retinal thinning. All eyes had undergone previous surgeries including silicone oil tamponade, and

Attosecond control of dissociative ionization of O(2) molecules

We demonstrate that dissociative ionization of O(2) can be controlled by the relative delay between an attosecond pulse train (APT) and a copropagating infrared (IR) field. Our experiments reveal a dependence of both the branching ratios between a range of electronic states and the fragment angular distributions on the extreme ultraviolet (XUV) to IR time delay. The observations go beyond adiabati

Dispersionless Spin Waves and Underlying Field-Induced Magnetic Order in Gadolinium Gallium Garnet.

We report the results of neutron diffraction and inelastic neutron scattering on a powder sample of Gd_{3}Ga_{5}O_{12} at high magnetic fields. Analysis of the diffraction data shows that in high fields (B≳1.8 T) the spins are not fully aligned, but are canted slightly as a result of the dipolar interaction. The magnetic phase for fields ≲1.8 T is characterized by antiferromagnetic peaks at (210)

Fibre intake and incident colorectal cancer depending on fibre source, sex, tumour location and Tumour, Node, Metastasis stage.

Studies on fibre intake and incident colorectal cancer (CRC) indicate inverse associations. Differences by tumour stage have not been examined. We examined associations between fibre intake and its sources, and incidental CRC. Separate analyses were carried out on the basis of sex, tumour location and the Tumour, Node, Metastasis (TNM) classification. The Malmö Diet and Cancer Study is a populatio

Pediobius cajanus sp n. (Hymenoptera, Eulophidae), an important natural enemy of the Asian fly (Melanagromyza obtusa (Malloch)) (Diptera, Agromyzidae) in the Dominican Republic

Pediobius cajanus sp. n. is described based on material from the Dominican Republic, where it is widespread, and it is anticipated to have a much larger distribution in tropical America. It is compared to other species of Pediobius from the New World, and is also compared to P. vignae (Risbec), a similar species from Africa with similar biology. The new species is a gregarious endoparasitoid of th

Age- and Sex-Specific Causal Effects of Adiposity on Cardiovascular Risk Factors.

Observational studies have reported different effects of adiposity on cardiovascular risk factors across age and sex. Since cardiovascular risk factors are enriched in obese individuals, it has not been easy to dissect the effects of adiposity from those of other risk factors. We used a Mendelian randomization approach, applying a set of 32 genetic markers to estimate the causal effect of adiposit

Magnitude and regulation of bacterioplankton respiratory quotient across freshwater environmental gradients

Bacterioplankton respiration (BR) may represent the largest single sink of organic carbon in the biosphere and constitutes an important driver of atmospheric carbon dioxide (CO2) emissions from freshwaters. Complete understanding of BR is precluded by the fact that most studies need to assume a respiratory quotient (RQ; mole of CO2 produced per mole of O-2 consumed) to calculate rates of BR. Many