Interleukin 2 activation of natural killer cells rapidly induces the expression and phosphorylation of the Leu-23 activation antigen.

IL-2 potentiates both growth and cytotoxic function of T lymphocytes and NK cells. Resting peripheral blood NK cells can respond directly to rIL-2, without requirement for accessory cells or cofactors, and enhanced cytotoxicity can be measured within a few hours after exposure to this lymphokine. In this study, we describe an activation antigen, Leu-23, that is rapidly induced and phosphorylated after IL-2 stimulation of NK cells and a subset of low buoyant density T lymphocytes. Previously, it has been uncertain whether all NK cells or only a subset are responsive to IL-2. Since within 18 h after exposure to IL-2, essentially all NK cells express Leu-23, these findings indicate that all peripheral blood NK cells are responsive to stimulation by IL-2. The Leu-23 antigen is a disulfide-bonded homodimer, composed of 24-kD protein subunits with two N-linked oligosaccharides. Appearance of this glycoprotein on NK cells is IL-2 dependent and closely parallels IL-2-induced cytotoxicity against NK-resistant solid tumor cell targets

Biocidal silver and silver/titania composite films grown by chemical vapour deposition

This paper describes the growth and testing of highly active biocidal films based on photocatalytically active films of TiO2, grownby thermal CVD, functionally and structurallymodified by deposition of nanostructured silver via a novel flame assisted combination CVD process. The resulting composite films are shown to be highly durable, highly photocatalytically active and are also shown to possess strong antibacterial behaviour. The deposition control, arising from the described approach, offers the potential to control the film nanostructure, which is proposed to be crucial in determining the photo and bioactivity of the combined film structure, and the transparency of the composite films. Furthermore, we show that the resultant films are active to a range of organisms, including Gram-negative and Gram-positive bacteria, and viruses. The very high-biocidal activity is above that expected from the concentrations of silver present, and this is discussed in terms of nanostructure of the titania/silver surface. These properties are especially significant when combined with the well-known durability of CVD deposited thin films, offering new opportunities for enhanced application in areas where biocidal surface functionality is sought

Highly bioactive silver and silver/titania composite films grown by chemical vapour deposition

This paper describes how photocatalytically active films of TiO2, grown by thermal CVD, may be functionally and structurally modified by deposition of nano-structured silver via a novel flame assisted CVD process. The resulting composite films are shown to be highly durable, highly photocatalytically active and are also shown to possess strong antibacterial behaviour. The deposition control, arising from the described approach, offers the potential to control the film nanostructure, which is proposed to be crucial in determining the photo and bio-activity of the combined film structure, and the transparency of the composite films. Furthermore, we show that the resultant films also exhibit “self-regeneration” capability, in that they both kill bacteria present on the film surface and then photo-degrade the residues. Such a dual action significantly reducing the problems of surface deactivation due to build up of contamination. These properties are especially significant when combined with the well-known durability of CVD deposited thin films, offering new opportunities for enhanced application in areas where bioactive surface functionality is sought

What factors increase the vulnerability of native birds to the impacts of alien birds?

Biodiversity impacts caused by alien species can be severe, including those caused by alien birds. In order to protect native birds, we aimed to identify factors that influence their vulnerability to the impacts of alien birds. We first reviewed the literature to identify native bird species sustaining such impacts. We then assigned impact severity scores to each native bird species, depending on the severity of the impacts sustained, and performed two types of analyses. First, we used contingency table tests to examine the distribution of impacts across their severity, type and location, and across native bird orders. Second, we used mixed‐effects models to test factors hypothesised to influence the vulnerability of native birds to the impacts of alien birds. Ground‐nesting shorebirds and seabirds were more prone to impacts through predation, while cavity‐nesting woodpeckers and parrots were more prone to impacts through competition. Native bird species were more vulnerable when they occupied islands, warm regions, regions with climatic conditions similar to those in the native range of the invading alien species, and when they were physically smaller than the invading alien species. To a lesser extent, they were also vulnerable when they shared habitat preferences with the invading alien species. By considering the number and type of native bird species affected by alien birds, we demonstrate predation impacts to be more widespread than previously indicated, but also that damaging predation impacts may be underreported. We identify vulnerable orders of native birds, which may require conservation interventions; characteristics of native birds that increase their vulnerability, which may be used to inform risk assessments; and regions where native birds are most vulnerable, which may direct management interventions. The impacts sustained by native birds may be going unnoticed in many regions of the world: there is a clear need to identify and manage them

Brain glucose sensing, glucokinase and neural control of metabolism and islet function.

It is increasingly apparent that the brain plays a central role in metabolic homeostasis, including the maintenance of blood glucose. This is achieved by various efferent pathways from the brain to periphery, which help control hepatic glucose flux and perhaps insulin-stimulated insulin secretion. Also, critically important for the brain given its dependence on a constant supply of glucose as a fuel--emergency counter-regulatory responses are triggered by the brain if blood glucose starts to fall. To exert these control functions, the brain needs to detect rapidly and accurately changes in blood glucose. In this review, we summarize some of the mechanisms postulated to play a role in this and examine the potential role of the low-affinity hexokinase, glucokinase, in the brain as a key part of some of this sensing. We also discuss how these processes may become altered in diabetes and related metabolic diseases.Funding and support from Wellcome Trust, Medical Research Council including the Cambridge MRC Centre for Study of Obesity and Related Disorders (MRC-CORD), NIHR Cambridge Biomedical Research Centre, Diabetes UK (RD05/003059) and Yousef Jameel Fund).This is the final version published version. It first appeared at http://onlinelibrary.wiley.com/doi/10.1111/dom.12334/abstract

Imaging Subtle Microstructural Variations in Ceramics with Precision Ultrasonic Velocity and Attenuation Measurements

There is an international research effort to incorporate ceramic components into hot sections of heat engines. A major portion of this effort is directed towards the understanding and control of ceramic processing so that the strength of ceramics may be optimized. To date, the strength of sintered ceramics (e.g., SiC) is well below, by about two orders of magnitude, the theoretical strength [1,4]. This discrepancy is understood to be due to the presence of voids, inclusions, agglomerates, and anomalously large grains [4]. These defects, causing premature failure, are introduced or formed during the ceramic manufacturing process. Considerable work has already been done to remove these strength reducing material variations. This has resulted in a steady increase in the fracture strength of ceramics; however, the rate of this increase has slowed. Adding to the problem is the fact that the fracture strength of identically produced experimental samples varies as much as 35 percent [2]. As a result of the loss of momentum toward higher strengths, researchers are turning to ceramic- ceramic fiber composites. These composites show promise of increasing the fracture strength of ceramic materials even further. It is likely that the same material strength variations will be present, at least locally in the matrix, in ceramic composites

Confirmation of low genetic diversity and multiple breeding females in a social group of Eurasian badgers from microsatellite and field data

The Eurasian badger ( Meles meles ) is a facultatively social carnivore that shows only rudimentary co-operative behaviour and a poorly defined social hierarchy. Behavioural evidence and limited genetic data have suggested that more than one female may breed in a social group. We combine pregnancy detection by ultrasound and microsatellite locus scores from a well-studied badger population from Wytham Woods, Oxfordshire, UK, to demonstrate that multiple females reproduce within a social group. We found that at least three of seven potential mothers reproduced in a group that contained 11 reproductive age females and nine offspring. Twelve primers showed variability across the species range and only five of these were variable in Wytham. The microsatellites showed a reduced repeat number, a significantly higher number of nonperfect repeats, and moderate heterozygosity levels in Wytham. The high frequency of imperfect repeats and demographic phenomena might be responsible for the reduced levels of variability observed in the badger