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Nocturnal autumn bird migration at Falsterbo, South Sweden

We investigated the patterns of nocturnal bird migration in autumn 1998 at a coastal site on the Falsterbo peninsula in south-western Sweden, by means of a passive infrared device. In total 17 411 flight paths, including track direction and altitude, of migrating birds were recorded for 68 nights from August to October. Mean migratory traffic rate per night varied between 6 and 6618 birds km1 h1,

Wound edge microvascular blood flow: effects of negative pressure wound therapy using gauze or polyurethane foam.

The aim of this study was to examine the effects of negative pressure wound therapy (NPWT) on wound edge microvascular blood flow, comparing different wound fillers. Wounds were created on the backs of 7 pigs. NPWT was applied, using either foam or gauze, at -50,-75, -100, -125, -150, or -175 mm Hg. Microvascular blood flow was measured in muscle tissue, subcutaneous tissue, and in the wound bed,

STRUCTURAL BASIS FOR CHROMOSOME X-LINKED AGAMMAGLOBULINEMIA - A TYROSINE KINASE DISEASE

X-linked agammaglobulinemia (XLA) is a hereditary defect of B-cell differentiation in man caused by deficiency of Bruton tyrosine kinase (BTK). A three-dimensional model for the BTK kinase domain, based on the core structure of cAMP-dependent protein kinase, was used to interpret the structural basis for disease in eight independent point mutations in patients with XLA. As Arg-525 of BTK has been

A viewpoint: Why chlorophyll a?

Chlorophyll a (Chl a) serves a dual role in oxygenic photosynthesis: in light harvesting as well as in converting energy of absorbed photons to chemical energy. No other Chl is as omnipresent in oxygenic photosynthesis as is Chl a, and this is particularly true if we include Chl a2, (=[8-vinyl]-Chl a), which occurs in Prochlorococcus, as a type of Chl a. One exception to this near universal patter

Escherichia coli P fimbriae utilize the Toll-like receptor 4 pathway for cell activation

Fimbriae mediate bacterial attachment to host cells and provide a mechanism for tissue attack. They activate a host response by delivery of microbial products such as lipopolysaccharide (LPS) or through direct fimbriae-dependent signalling mechanisms. By coupling to glycosphingolipid (GSL) receptors, P fimbriae trigger cytokine responses in CD14 negative host cells. Here we show that P fimbriae ut

The t+n+n system and 5H

The one-proton knockout channel from 6He (240 MeV/u) impinging on a carbon target has been investigated. The triton fragments originating from this channel were detected in coincidence with the two neutrons. A broad structure, peaked at 3 MeV above the t+2n threshold, is observed in the t+n+n-relative energy spectrum. It is shown that this structure is mainly due to a I(pi)=1/2(+) resonance as exp

Possible association between the androgen receptor gene and autism spectrum disorder

Autism is a highly heritable disorder but the specific genes involved remain largely unknown. The higher prevalence of autism in men than in women, in conjunction with a number of other observations, has led to the suggestion that prenatal brain exposure to androgens may be of importance for the development of this condition. Prompted by this hypothesis, we investigated the potential influence of

The mitochondrial external NADPH dehydrogenase modulates the leaf NADPH/NADP+ ratio in transgenic Nicotiana sylvestris

Plant mitochondria contain alternative external NAD(P)H dehydrogenases, which oxidise cytosolic NADH or NADPH and reduce ubiquinone without inherent linkage to proton pumping and ATP production. In potato, St-NDB1 is an external Ca2+-dependent NADPH dehydrogenase. The physiological function of this enzyme was investigated in homozygous Nicotiana sylvestris lines overexpressing St-ndb1 and co-suppr

Differential regulation of mnp2, a new manganese peroxidase-encoding gene from the ligninolytic fungus Trametes versicolor PRL 572

A peroxidase-encoding gene, mnp2, and its corresponding cDNA were characterized from the white-rot basidiomycete Trametes versicolor PRL 572. We used quantitative reverse transcriptase-mediated PCR to identify mnp2 transcripts in nutrient-limited stationary cultures. Although mnp2 lacks upstream metal response elements (MREs), addition of MnSO4 to cultures increased mnp2 transcript levels 250-fold

Strategies Applied by Women in Coping With ad-hoc Demands for Unauthorized User Fees During Pregnancy and Childbirth. A Focus Group Study From Angola.

Our aim in this study was to explore women's responses to reported ad-hoc demands for unauthorized user fees during pregnancy and childbirth in Luanda, Angola. Ten focus group discussions were conducted and data were analysed using grounded theory. Women were found to apply six strategies as they "endeavored to cope with demands for unauthorized user fees" (core category): (i) blowing the whistle,

Picosecond X-ray diffraction studies of laser-excited acoustic phonons in InSb

We have employed time-resolved X-ray diffraction with picosecond temporal resolution to measure the time-dependent rocking curves of laser-irradiated asymmetrically cut single InSb crystals. Coherent acoustic phonons were excited in the crystals by irradiation with 800-nm, 100-fs laser pulses at irradiances between 0.25 and 12 mJ/cm(2). The induced time-dependent strain profiles (corresponding to

Visual sensitivity in the crepuscular owl butterfly Caligo memnon and the diurnal blue morpho Morpho peleides: a clue to explain the evolution of nocturnal apposition eyes?

Insects active in dim light, such as moths and many beetles, normally have superposition compound eyes to increase photon capture. But there are nocturnal and crepuscular insects - such as some species of bees, wasps and butterflies - that have apposition compound eyes. These are likely to have adaptations - including large eye and facet size and coarsened spatial and temporal resolution - that im

Type 1 diabetes risk analysis on dried blood spot samples from population-based newborns: design and feasibility of an unselected case-control study

Development of type 1 diabetes mellitus (T1D) may be triggered pre- or perinatally by multiple factors. Identifying new predisposing T1D markers or combinations of markers in a large, well-characterised case-control collection may be important for future T1D prevention. The present work describes the design and feasibility of a large and unselected case-control study, which will define and evaluat

Enhanced concentration of COMP (cartilage oligomeric matrix protein) in osteochondral fractures from racing Thoroughbreds

The aim of the present study was to correlate the levels of COMP and aggrecan as indicators of tissue damage, in synovial fluid (sf) from carpal joints of acutely lame racehorses, with macroscopical lesions of articular cartilage (OA). osteochondral fractures and ligament tears found at arthroscopy. Sixty-three lame horses [49 Standardbred trotters (STB) and 14 Thoroughbreds (TB)] in conventional

Inhibition of cerebrospinal fluid formation by omeprazole

Omeprazole, a specific inhibitor of H(+)-K(+)-activated ATPase, gave a dose-dependent inhibition of CSF production as determined by cerebroventriculocisternal perfusions in the rabbit. The reduction was 35% when the perfusate concentration of omeprazole was 10(-6) M and 25% after an intravenous dose of 0.2 mg/kg of omeprazole, respectively. A similarly substituted benzimidazol (H178/42) without H(