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Blue stragglers as stellar collision products: the angular momentum question

We investigate the structure and evolution of blue straggler stars, which were formed from direct stellar collisions between main-sequence stars in globular clusters. In particular, we look at the rotational evolution of the products of off-axis collisions. As found in previous work, such blue stragglers initially have too high an angular momentum to contract down to the main sequence. We consider

Sexual selection: an evolutionary force in plants

Sexual selection has traditionally been used to explain exaggerated sexual traits in male animals. Today the concept has been developed and various other sexually related traits have been suggested to evolve in the same manner. In nearly all new areas where the theory of sexual selection has been applied, there has been an intense debate as to whether the application is justified. Is it the case t

Complete high-density lipoproteins in nanoparticle corona.

In a biological environment, nanoparticles immediately become covered by an evolving corona of biomolecules, which gives a biological identity to the nanoparticle and determines its biological impact and fate. Previous efforts at describing the corona have concerned only its protein content. Here, for the first time, we show, using size exclusion chromatography, NMR, and pull-down experiments, tha

Polymeric ultrafiltration membranes and surfactants.

Surfactants have been extensively used in ultrafiltration processes such as membrane cleaning,removal of surfactants or other organic toxic compounds and metal ions from solutions and estimation of interactions at surfactant and membrane interface. The aim of this review is to present the possibilities that arise from the data reported in the literature on the field of ultrafiltration (UF) membran

Platelets synthesize large amounts of active plasminogen activator inhibitor 1

Previous studies have suggested that plasminogen activator inhibitor 1 (PAI-1) released from platelets convey resistance of platelet-rich blood clots to thrombolysis. However, the majority of PAI-1 in platelets is inactive and therefore its role in clot stabilization is unclear. Because platelets retain mRNA and capacity for synthesis of some proteins, we investigated if platelets can de novo synt

The effect of pancreatic and biliary depletion on in vivo pharmacokinetics of digoxin in pigs

Several transporter systems in the liver and intestine are known to change their expression and function during cholestatic disease states. The objective of the-present in vivo study-was to investigate the effect of biliary depletion, as a method to mimic cholestasis, on the bioavailability and disposition of digoxin in biliary and pancreatic duct cannulated pigs. The study was divided in two part

Anaerobic digestion of lipid-rich waste - Effects of lipid concentration

The influence of lipid concentration on hydrolysis and biomethanation of a lipid-rich (triolein) model waste was evaluated in batch. The effect of increasing the concentration of lipid from 5% to 47% (w/w), based on chemical oxygen demand (COD), was investigated. The methane recovery observed was above 93% for all tests. An initial lag phase of approximately 6-10 days was observed for all tests. T

Early onset of action and efficacy of a combination of calcipotriene and betamethasone dipropionate in the treatment of psoriasis

Background: Calcipotriene and betamethasone dipropionate are topical treatments for psoriasis vulgaris. Their mode of action is different. Improved risk/benefit may result with concomitant use of the two compounds together. A new vehicle has been created with the objective of obtaining optimal stability of both calcipotriene and betamethasone dipropionate in the combination product. Objective. We

CO2-free power generation in combined cycles - Integration of post-combustion separation of carbon dioxide in the steam cycle

Ever since the release of the Kyoto protocol the demand for CO2-free processes have been increasing. One of the most expanding sources of electric power in the industrialised world today is the gas-fired combined cycle, combining high efficiency and low investment cost. In this paper, the integration of a post-combustion CO2-separation unit into a combined cycle is studied from a thermodynamic and

Driving to learn: powered wheelchair training for those with cognitive disabilities

The Driving to Learn project was an exploration of how those with significant cognitive disabilities could benefit from training in a joystick-operated powered wheelchair. This study focuses on a particular part of the wider Driving to Learn project, mainly looking at the relationship between characteristics connected to powered wheelchair-use and the trainees' success or failure in developing a c

Prediction of post-operative pain after a laparoscopic tubal ligation procedure.

Background: Pre-operative identification of reliable predictors of post-operative pain may lead to improved pain management strategies. We investigated the correlation between pre-operative pain, psychometric variables, response to heat stimuli and post-operative pain following a laparoscopic tubal ligation procedure. Methods: Assessments of anxiety, mood, psychological vulnerability and pre-opera

Professions and the Pursuit of Transparency in Healthcare: Two Cases of Soft Autonomy

Contemporary professions are increasingly challenged to open up to scrutiny from the outside. Earlier research is focused on two main types of responses and consequences: colonization by a managerial logic of self-monitoring and decoupling of auditing and professional practice. his paper describes a different type of response which implies that professionals get actively involved in monitoring the

Love thy neighbour? Social nesting pattern, host mass and nest size affect ectoparasite intensity in Darwin’s tree finches

Social nesting behaviour is commonly associated with high prevalence and intensity of parasites in intraspecific comparisons. Little is known about the effects of interspecific host breeding density for parasite intensity in generalist host–parasite systems. Darwin’s small tree finch (Camarhynchus parvulus) on Santa Cruz Island, Galápagos Islands, nests in both heterospecific aggregations and at s

Low serum testosterone and high serum estradiol associate with lower extremity peripheral arterial disease in elderly men - The MrOS study in Sweden

Objectives This study sought to determine whether serum levels of testosterone and estradiol associate with lower extremity peripheral arterial disease (PAD) in a large population-based cohort of elderly men. Background Few studies have explored the relationship between serum sex steroids and lower extremity PAD in men. Methods The Swedish arm of the MrOS (Osteoporotic Fractures in Men) study (n =

Smad7 promotes self-renewal of hematopoietic stem cells in vivo.

The Smad-signaling pathway downstream of the transforming growth factor–beta superfamily of ligands is an evolutionarily conserved signaling circuitry with critical functions in a wide variety of biologic processes. To investigate the role of this pathway in the regulation of hematopoietic stem cells (HSCs), we have blocked Smad signaling by retroviral gene transfer of the inhibitory Smad7 to muri

Limited male dispersal in a social spider with extreme inbreeding

Cooperatively breeding animals commonly avoid incestuous mating through pre-mating dispersal. However, a few group-living organisms, including the social spiders, have low pre-mating dispersal, intra-colony mating, and inbreeding. This results in limited gene flow among colonies and sub-structured populations. The social spiders also exhibit female-biased sex ratios because survival benefits to la