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Two barn swallows (Hirundo rustica) flying in the Lund wind tunnel were filmed using synchronised high-speed cameras to obtain posterior, ventral and lateral views of the birds in horizontal flapping flight. We investigated wingbeat kinematics, body tilt angle, tail spread and angle of attack at speeds of 414ms-1. Wingbeat frequency showed a clear U-shaped relationship with air speed with minima a

A comparative study on the bis(functionalization) of the Troger's base core by aromatic and heteroaromatic groups using palladium-catalyzed cross-coupling reactions is presented. Three different reactions, the Suzuki, Stille, and Negishi couplings, were investigated using Troger's base analogues equally substituted in the 2,8-positions with (HO)(2)B, Bu3Sn and ZnCl groups, respectively, as the met

We have investigated terahertz emission due to dynamical electron transport in wide-miniband GaAs/Al0.3Ga0.7As superlattices. By noting that the time-domain THz emission spectroscopy inherently measures the step-response of the electron system to the bias electric field, the obtained THz spectra were compared with the high-frequency conductivities predicted for miniband transport. Excellent agreem

The aim of the study was to evaluate the effect of both phytohaemagglutinin (PHA) alone, and in combination with alpha-ketoglutaric acid (AKG), on nitrogen elimination via the urinary tract as opposed to the gastrointestinal tract of rats. In experiment I, rats were assigned to one of two experimental groups, (1) Control and (2) PHA, whilst in experiment 2, rats were assigned to one of three exper

The ventilation and carbon dioxide elimination of each lung, and pulmonary arterial pressure, were studied in 17 patients during the early phases of anaesthesia for pulmonary surgery. The patients were ventilated mechanically to moderate hypocapnia. Expired tidal volume and carbon dioxide elimination rate of the lung to be operated on, and of the other lung, were similar in the supine position. Th

The maintenance of genetic variation for infection-related traits is often attributed to coevolution between hosts and parasites, but it can also be maintained by environmental variation if the relative fitness of different genotypes changes with environmental variation. To gain insight into how infection-related traits are sensitive to environmental variation, we exposed a single host genotype of

Modelling of pulverised wood flames in a laboratory vertical furnace was carried out. The aim was to gain deeper understanding of the combustion process and to validate a mathematical model to simulate the process. Pulverised wood combustion involves many different processes such as two-phase flow dynamics, drying and devolatilisation of the particles, oxidation of the volatile and formation and o

The two brown frogs Rana arvalis and Rana temporaria were monitored at 57 localities (that contained a total of 120 ponds) for up to 17 years each during the years 1989-2005. The analysis summarized below only accounts for trends within sites actually usable for frogs during the analysis period, large scale habitat losses are thus not accounted for. R. arvalis populations tended to increase over t

BACKGROUND: Previous studies indicate that analysis of the ST waveform of the fetal electrocardiogram provides information on the fetal response to hypoxia. We did a multicentre randomised controlled trial to test the hypothesis that intrapartum monitoring with cardiotocography combined with automatic ST-waveform analysis results in an improved perinatal outcome compared with cardiotocography alon

Analyzing a free boundary problem for harmonic functions in an infinite planar domain, we prove that in a solitary water wave each particle is transported in the wave direction but slower than the wave speed. As the solitary wave propagates, all particles located ahead of the wave crest are lifted, while those behind it experience a downward motion, with the particle trajectory having asymptotical

The brain has been suggested to be especially sensitive to damage by reactive oxygen species. In this study, we examined the effects of hyperoxic conditions on the activities and mRNA levels of antioxidant enzymes in reaggregation cultures of rat forebrain cells. Cultures were exposed to 80% oxygen for 12-60 h starting on Days 17 and 33 in culture. Superoxide dismutase activities and mRNA levels w

Hereditary non-polyposis colorectal cancer (HNPCC) is one of our most common cancer syndromes and an increasing number of individuals live in families with verified hereditary cancer. We conducted an interview study to explore experiences from and perceived impact on life after genetic testing for HNPCC. Three major themes emerged: reactions and emotions, family relations and implications for life

This article outlines an experimental and analytical expression study on the consequence of cement constituents, mix composition and curing conditions as regards self-desiccation in concrete. For this purpose nine concretes with three values of w/c (0.32, 0.38 and 0.50), based on two types of Portland Cement, were manufactured. Five per cent silica fume was used in one third of the concretes as ca

The existence of a DNA polymorphism at the hormone-sensitive lipase locus could be of great interest for genetic analysis of obesity and related disorders since hormone-sensitive lipase is the rate-limiting enzyme of adipose tissue lipolysis and therefore plays a key role in energy metabolism. The polymorphic dinucleotide repeat D19S120 was identified within a human genomic clone selected with a r

We present calculations of charm and beauty production at Tevatron within the framework of k(T)-factorization, using the unintegrated gluon distributions as obtained from the Linked Dipole Chain model. The analysis covers transverse momentum and rapidity distributions and the azimuthal correlations between b and (b) over bar quarks (or rather muons from their decay) which are powerful tests for th

Various new prognostic indicators have been identified for mammary carcinomas, but the issue of their significance remains unsettled. The prognostic impact of p53, c-erbB-2, and topoisomerase II alpha expression was investigated in relation to standard prognostic factors for carcinomas of the breast and to the tumour cell growth fraction. Paraffin-embedded specimens of 356 node-negative infiltrati

Estimation of parameters in the distribution of headways in roundabouts is a cumbersome task. Inherent to data employed are temporal variation together with dependence between successive vehicles. This is a consequence of the sampling period and interactions in the roundabouts. The elimination of observations, so as to obtain trend-free samples of independent vehicles, removes too much information