Sökresultat

Filtyp

Din sökning på "*" gav 548604 sökträffar

Dopamine responsiveness is regulated by targeted sorting of D2 receptors

Aberrant dopaminergic signaling is a critical determinant in multiple psychiatric disorders, and in many disease states, dopamine receptor number is altered. Here we identify a molecular mechanism that selectively targets D2 receptors for degradation after their activation by dopamine. The degradative fate of D2 receptors is determined by an interaction with G protein coupled receptor-associated s

Intraspecific variation in avian pectoral muscle mass: constraints on maintaining manoeuvrability with increasing body mass

1. Within a single year, long-distance migrants undergo a minimum of four cycles of fuel storage and depletion because their migrations have at least one stopover. Each cycle includes an almost twofold change in body mass (m(b)). Pervasive predation threats beg the question whether escape flight abilities keep up with such large changes in m(b). 2. We derive aerodynamic predictions how pectoral mu

Biological filtering of correlated environments: towards a generalised Moran theorem

Many species from diverse taxa are known to display synchronous fluctuations across vast geographical ranges. It is often thought that climate factors influencing the growth of conspecific populations are correlated over large distances and hence produce the synchronous population dynamics - an effect known as the Moran effect. However, for species embedded in a food web the Moran effect needs not

Basal metabolic rate in migratory waders: intra-individual, intraspecific, interspecific and seasonal variation

1. Basal metabolic rates (BMR) were measured in 36 adult and 119 juvenile waders of 19 species on autumn migration in southern Sweden. 2. Ina comparison with literature data, it was found that juvenile BMR was generally lower than at the onset of migration in the Arctic and slightly higher than on African wintering grounds. 3. The seasonal differences may reflect local physiological adaptations or

A novel fusion 5 ' AFF3/3 ' BCL2 originated from a t(2;18)(q11.2;q21.33) translocation in follicular lymphoma

Follicular lymphoma is the second most frequent type of non-Hodgkin's lymphoma in adults. The basic molecular defect consists of the t(14;18)(q32;q21) translocation, juxtaposing the B-cell lymphoma protein 2 gene BCL2 to the immunoglobulin heavy chain locus IGH@, and leading to the antiapoptotic BCL2 protein overproduction. Variations in the t(14;18) are rare and can be classified into two categor

Diblock polyampholytes grafted onto spherical particles: Monte Carlo simulation and lattice mean-field theory

Spherical brushes composed of diblock polyampholytes (diblock copolymers with oppositely charged blocks) grafted onto solid spherical particles in aqueous solution are investigated by using the primitive model solved with Monte Carlo simulations and by lattice mean-field theory. Polyampholyte chains of two compositions are considered: a copolymer with a long and a short block, A(100)B(10), and a c

Relativistic and correlated calculations on the ground and excited states of ThO.

We report on the performance of the third-order Douglas–Kroll ab initio model potential (DK3-AIMP) method-based electron-correlated spin–orbit calculations. Our treatment assumes that the problem can be separated into a spin–free correlation treatment and a spin–orbit calculation. The correlation effects were calculated using the multistate complete active space second-order perturbation method, a

Hydrophobic Interaction Capillary Electrochromatography of Protein Mutants. Use of Lipid-Based Liquid Crystalline Nanoparticles as Pseudostationary Phase.

Nanoparticle-based hydrophobic interaction-capillary electrochromatography was utilized for separation of proteins with similar mass-to-charge ratio at neutral pH without organic modifier. Lipid-based liquid crystalline nanoparticles were prepared and used as pseudostationary phase, benefiting from their high biocompatibility, ease of preparation, and suspension stability at high concentrations. U

Magma Ascent along a Major Terrane Boundary: Crustal Contamination and Magma Mixing at the Drumadoon Intrusive Complex, Isle of Arran, Scotland

The composite intrusions of Drumadoon and An Cumhann crop out on the SE coast of the Isle of Arran, Scotland and form part of the larger British and Irish Palaeogene Igneous Province, a subset of the North Atlantic Igneous Province. The intrusions (shallow-level dykes and sills) comprise a central quartz-feldspar-phyric rhyolite flanked by xenocryst-bearing basaltic andesite, with an intermediate

Gender differences and cognitive aspects on functional outcome after hip fracture-a 2 years' follow-up of 2,134 patients

Objective: we analysed outcome after hip fracture with respect to gender and cognitive function. Design: population-based, prospective cohort study. Setting: four university hospitals in Stockholm, Sweden. Subjects: a total of 2,134 consecutive patients admitted with hip fracture during 2003. Methods: gender differences in residence, walking ability and activity of daily living (ADL) were analysed

Exogenous leptin controls the development of the small intestine in neonatal piglets

Leptin, a hormone produced and secreted by adipose tissue, muscles and stomach, is involved in the regulation of adipose tissue mass, food intake and body weight in neonatal animals. It is also produced in the mammary glands and secreted into the colostrum and milk. Since leptin receptors are widely distributed in the small intestine mucosa, the aim of the present study was to investigate the effe

Wheelchair accessibility of public buildings in Al Ain, United Arab Emirates (UAE)

Purpose: The purpose of this study was to assess the accessibility to public buildings for wheelchair users in Al Ain, the fourth largest city of the United Arab Emirates. Method: Data were collected at 17 buildings, randomly chosen using the local telephone book as source. The instrument used was a survey form covering eight accessibility areas: parking, ramps, entrances, accessible routes, toile

Arterial rupture after microwave-induced hyperthermia and radiotherapy. With reference to two patients treated for recurrence in previously operated and irradiated areas

Two patients who developed frank arterial bleeding after combined microwave-induced hyperthermia and radiotherapy are described. One patient received re-irradiation and hyperthermia for recurrent metastatic neck nodes of a mesopharyngeal carcinoma. Full course radiotherapy had been given 6 years previously and a right-sided radical neck node dissection had been performed 4 months earlier because o

Alien species in a warmer world: risks and opportunities

Climate change and biological invasions are key processes affecting global biodiversity, yet their effects have usually been considered separately. Here, we emphasise that global warming has enabled alien species to expand into regions in which they previously could not survive and reproduce. Based on a review of climate-mediated biological invasions of plants, invertebrates, fishes and birds, we

Reduction of cyanobacterial toxins through coprophagy in Mytilus edulis

An experiment was conducted to follow the fate of the cyanobacterial toxin, nodularin, produced by Nodularia spumigena through ingestion by Mytilus edulis and re-ingestion of faecal material (coprophagy). Mussels were fed with cultures of N. spumigena, and the faeces that were produced were fed to other mussels not previously exposed to N. spumigena. Concentrations of nodularin were measured in th

The reductive fragmentation of 7-hydroxy-9,10-dioxotaxoids.

The retro-aldol reductive fragmentation of different structural types of 7-hydroxy-9,10-dioxotaxoids was investigated, showing that the reaction is typical of taxanes and requires cerium(III) promotion with NaBH4 in protic medium and alkylboron (aluminium) hydrides in aprotic solvents. The resulting 7,8-seco-taxanes are key intermediates for the synthesis of a novel class of anticancer taxanes end

Colour constancy in diurnal and nocturnal hawkmoths

Diurnal and nocturnal hawkmoths have been shown to use colour vision for flower discrimination. Here, we present evidence that the nocturnal hawkmoth Deilephila elpenor and the diurnal hawkmoth Macroglossum stellatarum also have colour constancy. Colour constancy was shown in D. elpenor in two multiple-choice experiments with five different bluish colour patches under white and blue illumination a

Sons are made from old stores: sperm storage effects on sex ratio in a lizard

Sperm storage is a widespread phenomenon across taxa and mating systems but its consequences for central fitness parameters, such as sex ratios, has rarely been investigated. In Australian painted dragon lizards (Ctenophorus pictus), we describe elsewhere that male reproductive success via sperm competition is largely an effect of sperm storage. That is, sperm being stored in the female reproducti