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How swifts control their glide performance with morphing wings

Gliding birds continually change the shape and size of their wings(1-6), presumably to exploit the profound effect of wing morphology on aerodynamic performance(7-9). That birds should adjust wing sweep to suit glide speed has been predicted qualitatively by analytical glide models(2,10), which extrapolated the wing's performance envelope from aerodynamic theory. Here we describe the aerodynamic a

Methods and uncertainties in bioclimatic envelope modelling under climate change

Potential impacts of projected climate change on biodiversity are often assessed using single-species bioclimatic 'envelope' models. Such models are a special case of species distribution models in which the current geographical distribution of species is related to climatic variables so to enable projections of distributions under future climate change scenarios. This work reviews a number of cri

Nomenclatural notes to Flora Nordica Vol. 6 (Thymelaeaceae-Apiaceae)

The following names in Flora Nordica Vol. 6 are subject to nomenclatural action: Helianthemum oelandicum var. canescens (typified), Epilobium hornemannii (typified), Oenothera nuda (validated), Myriophyllum spicatum (emendation of typification), Viola rupestris subsp. relicta (typified), Hippophae rhamnoides (typified), Angelica archangelica subsp. littoralis (typified). - Flora Nordica Note no. 3

Two-dimensional temperature measurements in flames using filtered Rayleigh scattering at 254 nm

Two-dimensional temperature measurements using filtered Rayleigh scattering (FRS) have been demonstrated. A tunable single-longitudinalmode alexandrite laser was employed to provide the tunable narrow-linewidth ultraviolet laser beam at 254 nm. Isotopic-enhanced mercury was utilized as an ultraviolet atomic filter. The strong absorption of the filter enabled effective suppression of elastic backgr

Atrial fibrillatory rate and risk of left atrial thrombus in atrial fibrillation.

ims In atrial fibrillation (AF), a relation between electrocardiogram (ECG) fibrillatory wave amplitude and thrombus formation has been sought for long with conflicting results. In contrast, the possible relation between atrial fibrillatory rate obtained from the surface ECG and left atrial thrombus formation in patients with AF is unknown and was consequently evaluated in this study. Methods and

Mechanisms of adaptation to nitrosative stress in Bacillus subtilis

Bacteria use a number of mechanisms for coping with the toxic effects exerted by nitric oxide (NO) and its derivatives. Here we show that the flavohemoglobin encoded by the hmp gene has a vital role in an adaptive response to protect the soil bacterium Bacillus subtilis from nitrosative stress. We further show that nitrosative stress induced by the nitrosonium cation donor sodium nitroprusside (SN

Aromatic interactions define the binding of the alphavirus spike to its nucleocapsid

Background: Most enveloped viruses bud from infected cells by a process in which viral intracellular core components interact with cytoplasmic domains of transmembrane spike glycoproteins. We have demonstrated previously that a tyrosine motif in the cytoplasmic domain of the Semliki Forest virus (SFV) spike glycoprotein E2 is absolutely essential for budding, In contrast, hardly anything is known

Binding of [3H]-5-hydroxytryptamine to human coronary artery and bypass graft vessels

OBJECTIVES: 5-Hydroxytryptamine (5-HT) has a wide range of vascular effects mediated via specific receptors and it has been suggested to be a mediator in ischemic heart disease. The aim of the present study was to localise the 5-HT receptors within the vessel wall. METHODS: Epicardial coronary arteries obtained from patients undergoing cardiac transplantation, internal mammary arteries from heart

Paternal alleles enhance female reproductive success in tropical pythons

The conventional view that female reproductive success is unlikely to benefit from multiple mating has come under strong challenge in recent years. In the present study, we demonstrate that the time wild-caught reproductive female water pythons (Liasis fuscus) spent in the laboratory prior to oviposition affected both hatching success and the number of male microsatellite alleles detected in the b

Proton MR spectroscopy in clinical routine

In vivo magnetic resonance spectroscopy (MRS) addresses metabolic pathways and their steady states in different tissue types. The brain has by tradition, and due to technical limitations in other organs, been one of the tissues most studied by MRS, and both 1H- and 31P-MRS have been used. Although 31P-MRS is outstanding for the evaluation of sources of metabolic energy in the brain, 1H-MRS has bec

Intention to respond to local wind turbines: The role of attitudes and visual perception

Wind power projects frequently face public opposition during the siting process. A deeper understanding of social factors has therefore been called for. Based on psychological theories, the present research was initiated in order to study the relative importance of individual aspects related to visual perception and attitudinal factors in public intention to oppose local wind turbines. In an empir

Capsaicin receptor immunoreactivity in the human trigeminal ganglion.

The cloned capsaicin receptor, also known as vanilloid receptor subtype 1 (VR1) receptor, has been demonstrated to be an integral membrane protein with homology to a family of putative store-operated calcium channels. The VR1 receptor is activated not only by capsaicin but also by noxious heat and protons, and therefore it is suggested as a molecular integrator of chemical and physical stimuli tha

Oxygen measurement by multimode diode lasers employing gas correlation spectroscopy

Multimode diode laser (MDL)-based correlation spectroscopy (COSPEC) was used to measure oxygen in ambient air, thereby employing a diode laser (DL) having an emission spectrum that overlaps the oxygen absorption lines of the A band. A sensitivity of 700 ppm m was achieved with good accuracy (2%) and linearity (R-2 = 0.999). For comparison, measurements of ambient oxygen were also performed by tuna

First-Principle Calculations of the Experimental Vibrational Spectrum of a Surface Adsorbate: Anharmonic Resonance Coupling between Fundamental and Binary Modes.

By including relevant physical properties in our modeling of a surface adsorbate system we can, from first principles, correctly calculate all experimentally observed features in the vibrational spectrum of CH3CH2O– and CD3CH2O– adsorbed on Cu(100). That is, we reproduce the number of observed modes, the vibrational frequencies, and intensities of the modes including the presence/absence of binary

Polarizability and optical rotation calculated from the approximate coupled cluster singles and doubles CC2 linear response theory using Cholesky decompositions

A new implementation of the approximate coupled cluster singles and doubles CC2 linear response model using Cholesky decomposition of the two-electron integrals is presented. Significantly reducing storage demands and computational effort without sacrificing accuracy compared to the conventional model, the algorithm is well suited for large-scale applications. Extensive basis set convergence studi