83 resultados para Stateful view


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Viral fusion proteins mediate the merger of host and viral membranes during cell entry for all enveloped viruses. Baculovirus glycoprotein gp64 (gp64) is unusual in promoting entry into both insect and mammalian cells and is distinct from established class I and class II fusion proteins. We report the crystal structure of its postfusion form, which explains a number of gp64's biological properties including its cellular promiscuity, identifies the fusion peptides and shows it to be the third representative of a new class (III) of fusion proteins with unexpected structural homology with vesicular stomatitis virus G and herpes simplex virus type 1 gB proteins. We show that domains of class III proteins have counterparts in both class I and II proteins, suggesting that all these viral fusion machines are structurally more related than previously thought.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Plants encounter numerous pests and pathogens in the natural environment. An appropriate response to attack by such organisms can lead to tolerance or resistance mechanisms that enable the plant to survive. Many studies concentrate on the signalling pathways that enable plants to recognize and respond to attack, and measure the downstream effect in either biochemical or molecular terms. At the whole plant level, ecologists examine the fitness costs of attack not only for the plant but also over a range of trophic levels. The links between these differing levels of study are beginning to be addressed by the adoption of molecular approaches in more ecologically relevant settings. This review will describe the different approaches used by ecologists and cell biologists in this field and will try to address the question of how we can explore the response to, and consequences, of attack by multiple enemies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Publication rate of patents can be a useful measure of innovation and productivity in fields of science and technology. To assess the growth in industrially-important research, I conducted an appraisal of patents published between 1985 and 2005 on online databases using keywords chosen to select technologies arising as a result of biological inspiration. Whilst the total number of patents increased over the period examined, those with biomimetic content had increased faster as a proportion of total patent publications. Logistic regression analysis reveals that we may be a little over half way through an initial innovation cycle inspired by biological systems.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Research and informed debate reveals that institutional practices in relation to research degree examining vary considerably across the sector. Within a context of accountability and quality assurance/total quality management, the range and specificity of criteria that are used to judge doctoral work is of particular relevance. First, a review of the literature indicates that, although interest in and concern about the process is burgeoning, there is little empirical research published from which practitioners can draw guidance. The second part of the paper reviews that available research, drawing conclusions about issues that seem to pertain at a general level across disciplines and institutions. Lest the variation is an artefact of discipline difference, the third part of the paper focuses on a within discipline study. Criteria expected/predicted by supervisors are compared and contrasted with those anticipated and experienced by candidates and with those implemented and considered important by examiners. The results are disturbing.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Rose Review into the teaching of early reading recommended that the conceptual framework incorporated into the National Literacy Strategy Framework for Teaching – the Searchlights model of reading and its development – should be replaced by the Simple View of Reading. In this paper, we demonstrate how these two frameworks relate to each other, and show that nothing has been lost in this transformation from Searchlights to Simple View: on the contrary, much has been gained. That nothing has been lost is demonstrated by consideration of the underlying complexity inherent in each of the two dimensions delineated in the Simple View. That much has been gained is demonstrated by the increased understanding of each dimension that follows from careful scientific investigation of each. The better we understand what is involved in each dimension, the better placed we are to unravel and understand the essential, complex and continual interactions between each dimension which underlie skilled reading. This has clear implications for further improving the early teaching of reading.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The ENABLE project, which is partly funded by the European Commission, aims to assist elderly people to live well, independently and at case. In this project a wrist unit with both integrated and external sensors, and with a radio frequency link to a mobile phone. will be developed. ENABLE will provide a number of services for elderly people. among them also a remote control service for the home environment. This paper briefly describes the project in general and then focuses on the initial user needs investigation which was carried Out in early 2007 in six different European countries. The provisional findings are discussed and an outlook on the ongoing and future project work is given. A special focus of this paper is on the environmental control service.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper addresses the nature and cause of Specific Language Impairment (SLI) by reviewing recent research in sentence processing of children with SLI compared to typically developing (TD) children and research in infant speech perception. These studies have revealed that children with SLI are sensitive to syntactic, semantic, and real-world information, but do not show sensitivity to grammatical morphemes with low phonetic saliency, and they show longer reaction times than age-matched controls. TD children from the age of 4 show trace reactivation, but some children with SLI fail to show this effect, which resembles the pattern of adults and TD children with low working memory. Finally, findings from the German Language Development (GLAD) Project have revealed that a group of children at risk for SLI had a history of an auditory delay and impaired processing of prosodic information in the first months of their life, which is not detectable later in life. Although this is a single project that needs to be replicated with a larger group of children, it provides preliminary support for accounts of SLI which make an explicit link between an early deficit in the processing of phonology and later language deficits, and the Computational Complexity Hypothesis that argues that the language deficit in children with SLI lies in difficulties integrating different types of information at the interfaces.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Svalgaard and Cliver (2010) recently reported a consensus between the various reconstructions of the heliospheric field over recent centuries. This is a significant development because, individually, each has uncertainties introduced by instrument calibration drifts, limited numbers of observatories, and the strength of the correlations employed. However, taken collectively, a consistent picture is emerging. We here show that this consensus extends to more data sets and methods than reported by Svalgaard and Cliver, including that used by Lockwood et al. (1999), when their algorithm is used to predict the heliospheric field rather than the open solar flux. One area where there is still some debate relates to the existence and meaning of a floor value to the heliospheric field. From cosmogenic isotope abundances, Steinhilber et al. (2010) have recently deduced that the near-Earth IMF at the end of the Maunder minimum was 1.80 ± 0.59 nT which is considerably lower than the revised floor of 4nT proposed by Svalgaard and Cliver. We here combine cosmogenic and geomagnetic reconstructions and modern observations (with allowance for the effect of solar wind speed and structure on the near-Earth data) to derive an estimate for the open solar flux of (0.48 ± 0.29) × 1014 Wb at the end of the Maunder minimum. By way of comparison, the largest and smallest annual means recorded by instruments in space between 1965 and 2010 are 5.75 × 1014 Wb and 1.37 × 1014 Wb, respectively, set in 1982 and 2009, and the maximum of the 11 year running means was 4.38 × 1014 Wb in 1986. Hence the average open solar flux during the Maunder minimum is found to have been 11% of its peak value during the recent grand solar maximum.