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The wingbeat kinematics of a thrush nightingale Luscinia luscinia were measured for steady flight in a wind tunnel over a range of flight speeds (5-10 m s(-1)), and the results are interpreted and discussed in the context of a detailed, previously published, wake analysis of the same bird. Neither the wingbeat frequency nor wingbeat amplitude change significantly over the investigated speed range

In hybrid zones genetically differentiated populations meet and interbreed. As they result from ongoing divergence and potential speciation, such zones provide opportunities to study how different factors affect this process. One well-known avian hybrid zone is that between the Hooded Crow Corvus corone cornix and Carrion Crow C. c. corone, which extends throughout much of Europe. We compare the c

Nine species of hyoliths are described based on material collected in Skane, southern Sweden, during the first half of the last century. The material derives from the middle Cambrian (Cambrian provisional Series 3) Exsulans Limestone Bed at Almbacken east of Lund and the Upper Ordovician (Katian-Hirnantian) Lindegard Formation at Tommarp west of Simrishamn. The Almbacken assemblage consists of thr

Isotoma klovstadi Carpenter, 1902 was one of the first Collembola described from the Antarctic continent. It was first collected in November 1899 during the British Antarctic Expedition on the north coast of Victoria Land in the Ross Sea region. It is now known to occur in an extensive area of northern Victoria Land, including the offshore Possession, Coulman, and Foyn Islands. More recently, L kl

Swifts, Apus apus, spend the night aloft and this offers an opportunity to test the degree of adaptability of bird orientation and flight to different ecological situations. We predicted the swifts' behaviour by assuming that they are adapted to minimize energy expenditure during the nocturnal flight and during a compensatory homing flight if they become displaced by wind. We tested the prediction

Intra-abdominal adhesions are normally found after most surgical procedures. Many of the adhesions are asymptomatic, but in about 5% they will lead to readmission due to adhesion-related disorders, such as small bowel obstruction, pelvic pain and infertility. This review discusses possible ways to prevent abdominal adhesions and provides an update as comes to where we stand today in research regar

The copper coordination geometry in the blue copper proteins plastocyanin, nitrite reductase, cucumber basic protein, and azurin has been studied by combined density functional (B3LYP) and molecular mechanical methods. Compared to quantum chemical vacuum calculations, a significant improvement of the geometry is seen (toward the experimental structures) not only for the dihedral angles of the liga

Driver comprehension and acceptance of the active accelerator pedal (AAP) after long-term use were evaluated in a large-scale Swedish trial held in 2000-2002. The system was installed in the cars of 281 test drivers who then used it for between six months and a year. The participants' responses, elicited by questionnaires in the end of the trial, showed a positive rating of the concept of the AAP,

A detailed experimental investigation has been made of the pyrolysis-the first step in biomass combustion-of single birchwood particles. In addition to mass spectrometric and gravimetric analysis, the pyrolysis volatiles were characterized by different optical techniques. Absorption measurements showed a nearly featureless absorption in the ultraviolet spectral region with a continuously stronger

Human activated protein C (APC) is a key component of a natural anticoagulant system that regulates blood coagulation. In vivo, the catalytic activity of APC is regulated by two serpins, alpha1-antitrypsin and the protein C inhibitor (PCI), the inhibition by the latter being stimulated by heparin. We have identified a heparin-binding site in the serine protease domain of APC and characterized the

Objective: To characterise uterine proteoglycans and changes therein during pregnancy and labour. Study Design: Uterine samples were collected from 6 non-pregnant, 10 term-pregnant and from 10 women in active tabour. The proteoglycans were extracted by 4 M guanidine hydrochloride and precipitated with Alcian Blue. They were separated by electrophoresis and identified by Western blotting. Results:

Comments on Sæbjørg Walaker Nordeide & Steinar Gulliksen: First Generation Christians, Second Generation Radiocarbon Dates, an article in Norwegian Archaeological Review 40, no 1 (2007).

Both ovariectomy (Ovx) and gastrectomy (Gx) induce osteopaenia in rats and humans. While the effect of Ovx has been ascribed to oestrogen deficiency, the underlying mechanism behind Gx is poorly understood. Alendronate, oestrogen and parathyroid hormone (PTH) are known to prevent the osteopaenia induced by Ovx in rats. The purpose of the present study was to determine whether alendronate, oestroge

The evaluation of chondroid lesions requires full integration of clinical, radiographic, and pathological data; tumour typing is often a challenge for the diagnostic pathologist. Although a variety of chromosomal abnormalities have been documented in chondroid lesions, the potential usefulness of cytogenetic analysis remains unclear. This study has critically reviewed and analysed 117 karyotyped s

For the last four decades there has been sustained scientific interest in contemporary environmental change in the Sahel (the southern fringe of the Sahara). It suffered several devastating droughts and famines between the late 1960s and early 1990s. Speculation about the climatology of these droughts is unresolved, as is speculation about the effects of land clearance on rainfall and about land d

Fe-only hydrogenases are enzymes that catalyze dihydrogen production or oxidation, due to the presence of an unusual Fe6S6 cluster (the so-called H-cluster) in their active site, which is composed of a Fe2S2 subsite, directly involved in catalysis, and a classical Fe4S4 cubane cluster. Here, we present a hybrid quantum mechanical and molecular mechanical (QM/MM) investigation of the Fe-only hydrog

Species of Phragmoceras in the Silurian of Gotland and Britain are reviewed and revised. One new species P. exaggeratus is described from the Ludlow Series of the Welsh Borderland. There are comments on the broader distribution of the genus and on its mode of life.