856 resultados para Well-established biomarkers


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Scientists hold a wide range of beliefs on matters of religion, although popular media coverage in the UK commonly suggests that atheism is a core commitment for scientists. Considering the relationship between religion and science is a recommended topic in the English National Curriculum for lower secondary pupils (11-14 year-olds), and it is expected that different perspectives will be considered. However it is well established that many pupils may have difficulty accessing sophisticated ideas about the nature of science, and previous research suggests some may identify science with scientism. To explore pupil impressions of the relationship between science and religion, 13-14 year old pupils were surveyed in one class from each of four English secondary schools, by asking them to rate a set of statements about the relationship between science and religion, and scientific and religious perspectives on the origins of the world, and of life on earth, on the value of prayer and on the status of miracles. The survey revealed diverse views on these issues, reflecting the wider society. However it was found that a considerable proportion of the pupils in the sample considered religious beliefs and scientific perspectives to be opposed. The basis and potential consequences of such views are considered, and the need for more attention to this area of student thinking is highlighted.

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Purpose - The role of affective states in consumer behaviour is well established. However, no study to date has empirically examined online affective states as a basis for constructing typologies of internet users and for assessing the invariance of clusters across national cultures. Design/methodology/approach - Four focus groups with internet users were carried out to adapt a set of affective states identified from the literature to the online environment. An online survey was then designed to collect data from internet users in four Western and four East Asian countries. Findings - Based on a cluster analysis, six cross-national market segments are identified and labelled "Positive Online Affectivists", "Offline Affectivists", "On/Off-line Negative Affectivists", "Online Affectivists", "Indistinguishable Affectivists", and "Negative Offline Affectivists". The resulting clusters discriminate on the basis of national culture, gender, working status and perceptions towards online brands. Practical implications - Marketers may use this typology to segment internet users in order to predict their perceptions towards online brands. Also, a standardised approach to e-marketing is not recommended on the basis of affective state-based segmentation. Originality/value - This is the first study proposing affective state-based typologies of internet users using comparable samples from four Western and four East Asian countries.

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It is now well established that the prevalence of mental health difficulties in individuals with autism spectrum disorders (ASD) is considerably higher than in the general population. With recent estimates of the prevalence of autism spectrum disorders being as high as one percent, increasing numbers of children and young people are presenting to local and specialist services with mental health problems in addition to a diagnosis of ASD. Many families report that the impact of the mental health problems can be as or more impairing than the autism spectrum difficulties themselves. Clinical services are frequently called upon to treat these difficulties; however, there is limited evidence for the effectiveness of treatments in this population. This paper reports a case series of children and adolescents with ASD and an anxiety disorder who were treated with a standard cognitive behaviour therapy (CBT) rationale adapted to take account of the neuropsychological features of ASD. Common features of the presentation of the disorders and also treatment processes are discussed.

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Models used in neoclassical economics assume human behaviour to be purely rational. On the other hand, models adopted in social and behavioural psychology are founded on the ‘black box’ of human cognition. In view of these observations, this paper aims at bridging this gap by introducing psychological constructs in the well established microeconomic framework of choice behaviour based on random utility theory. In particular, it combines constructs developed employing Ajzen’s theory of planned behaviour with Lancaster’s theory of consumer demand for product characteristics to explain stated preferences over certified animal-friendly foods. To reach this objective a web survey was administered in the largest five EU-25 countries: France, Germany, Italy, Spain and the UK. Findings identify some salient cross-cultural differences between northern and southern Europe and suggest that psychological constructs developed using the Ajzen model are useful in explaining heterogeneity of preferences. Implications for policy makers and marketers involved with certified animal-friendly foods are discussed.

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Cannabis sativa has been associated with contradictory effects upon seizure states despite its medicinal use by numerous people with epilepsy. We have recently shown that the phytocannabinoid cannabidiol (CBD) reduces seizure severity and lethality in the well-established in vivo model of pentylenetetrazoleinduced generalised seizures, suggesting that earlier, small-scale clinical trials examining CBD effects in people with epilepsy warrant renewed attention. Here, we report the effects of pure CBD (1, 10 and 100 mg/kg) in two other established rodent seizure models, the acute pilocarpine model of temporal lobe seizure and the penicillin model of partial seizure. Seizure activity was video recorded and scored offline using model-specific seizure severity scales. In the pilocarpine model CBD (all doses) significantly reduced the percentage of animals experiencing the most severe seizures. In the penicillin model, CBD (�10 mg/kg) significantly decreased the percentage mortality as a result of seizures; CBD (all doses) also decreased the percentage of animals experiencing the most severe tonic–clonic seizures. These results extend the anticonvulsant profile of CBD; when combined with a reported absence of psychoactive effects, this evidence strongly supports CBD as a therapeutic candidate for a diverse range of human epilepsies.

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Acrylamide, a chemical that is probably carcinogenic in humans and has neurological and reproductive effects, forms from free asparagine and reducing sugars during high-temperature cooking and processing of common foods. Potato and cereal products are major contributors to dietary exposure to acrylamide and while the food industry reacted rapidly to the discovery of acrylamide in some of the most popular foods, the issue remains a difficult one for many sectors. Efforts to reduce acrylamide formation would be greatly facilitated by the development of crop varieties with lower concentrations of free asparagine and/or reducing sugars, and of best agronomic practice to ensure that concentrations are kept as low as possible. This review describes how acrylamide is formed, the factors affecting free asparagine and sugar concentrations in crop plants, and the sometimes complex relationship between precursor concentration and acrylamide-forming potential. It covers some of the strategies being used to reduce free asparagine and sugar concentrations through genetic modification and other genetic techniques, such as the identification of quantitative trait loci. The link between acrylamide formation, flavour, and colour is discussed, as well as the difficulty of balancing the unknown risk of exposure to acrylamide in the levels that are present in foods with the well-established health benefits of some of the foods concerned. Key words: Amino acids, asparagine, cereals, crop quality, food safety, Maillard reaction, potato, rye, sugars, wheat.

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It is well established that the glutamate decarboxylase (GAD) system is central to the survival of Listeria monocytogenes at low pH, both in acidic foods and within the mammalian stomach. The accepted model proposes that under acidic conditions extracellular glutamate is transported into the cell in exchange for an intracellular gamma-aminobutyrate (GABA(i)). The glutamate is then decarboxylated to GABA(i), a reaction that consumes a proton, thereby helping to prevent acidification of the cytoplasm. In this study, we show that glutamate supplementation had no influence on either growth rate at pH 5.0 or survival at pH 2.5 when L. monocytogenes 10403S was grown in a chemically defined medium (DM). In response to acidification, cells grown in DM failed to efflux GABA, even when glutamate was added to the medium. In contrast, in brain heart infusion (BHI), the same strain produced significant extracellular GABA (GABA(e)) in response to acidification. In addition, high levels of GABA(i) (>80 mM) were found in the cytoplasm in response to low pH in both growth media. Medium-swap and medium-mixing experiments revealed that the GABA efflux apparatus was nonfunctional in DM, even when glutamate was present. It was also found that the GadT2D2 antiporter/decarboxylase system was transcribed poorly in DM-grown cultures while overexpression of gadD1T1 and gadD3 occurred in response to pH 3.5. Interestingly, BHI-grown cells did not respond with upregulation of any of the GAD system genes when challenged at pH 3.5. The accumulation of GABA(i) in cells grown in DM in the absence of extracellular glutamate indicates that intracellular glutamate is the source of the GABA(i). These results demonstrate that GABA production can be uncoupled from GABA efflux, a finding that alters the way we should view the operation of bacterial GAD systems.

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Local food initiatives create a niche market in many developed countries where consumer choice is being met with an expanding offering in both conventional as well as complementary retail outlets. Supermarkets in conjunction with the food service sector currently dominate food sales and consumption, and are likely to do so for the foreseeable future. However, the local food sector offers an opportunity for implementing niche marketing strategies for many businesses. Local food activities tend to be relatively independent activities and a clearer definition for “local” food would assist in consolidating this important component of the food system. Related to this, consumers would benefit from the establishment of some form of assurance system for the ‘localness’ of food. In the UK, with its well established local food market, farmers’ markets, farm shops and box schemes are currently having the largest impact in terms of total sales. Hence further research is required to confirm that support for similar business ventures in Australia would be a viable strategy for strengthening its local food systems.

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The central role of immune-receptorlike signaling mechanisms in the activation of platelets at sites of vascular injury is well established. Of equal importance to the regulatory systems that control the activation of platelets are those systems that negatively regulate platelets and thereby prevent inappropriate platelet activation and thrombosis. Recent reports have identified a new mechanism through which this may be achieved, which involves signaling via a receptor that contains an immunoreceptor tyrosine-based inhibitory motif (ITIM). The role of ITIMs in the control of platelet function is the subject of this review.

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In recent times there has been a growing recognition amongst policy-makers of the role for community-based action in contributing to the broader aims of energy policy and climate change. In this paper, we will examine the potential for existing community groups to use their influence and elements of internal cohesion to encourage more widespread understanding and adoption of sustainable lifestyle habits; both amongst their members and within the broader communities of which they are a part. Findings are presented from recent empirical work with a range of well-established community groups for whom environmental issues are not their main priority. A central aspect of the research was to explore both the current status and potential role of groups that may have the capacity to reach and influence a broader sphere of the public than energy/environment specific initiatives of recent times have been able to achieve. Representing a diversity of interests, age groups and functionality, the results suggest that the potential for more effective ‘bottom-up’ engagement on climate change and sustainable living might be given fresh impetus by these types of established community groups and their networks. An assessment of what motivates participation and membership in the groups highlights a series of factors common to all groups and a smaller number that are significant for particular groups individually. It is argued that an appreciation of motivating factors can be useful in understanding more clearly how such groups are able to survive and maintain cohesion over time. The findings also suggest that climate change action means different things for different groups, with the diversity of the groups bringing with it the challenge of making sustainable living relevant to a range of interests and different shared values.

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Reliable and sufficiently discriminative methods are needed for differentiating individual strains of Salmonella enterica serotype Enteritidis beyond the phenotypic level; however, a consensus has not been reached as to which molecular method is best suited for this purpose. In addition, data are lacking on the molecular fingerprinting of serotype Enteritidis from poultry environments in the United Kingdom. This study evaluated the combined use of classical methods (phage typing) with three well-established molecular methods (ribotyping, macrorestriction analysis of genomic DNA, and plasmid profiling) in the assessment of diversity within 104 isolates of serotype Enteritidis from eight unaffiliated poultry farms in England. The most sensitive technique for identifying polymorphism was PstI-SphII ribotyping, distinguishing a total of 22 patterns, 10 of which were found among phage type 4 isolates. Pulsed-field gel electrophoresis of XhaI-digested genomic DNA segregated the isolates into only six types with minor differences between them. In addition, 14 plasmid profiles were found among this population. When all of the typing methods were combined, 54 types of strains were differentiated, and most of the poultry farms presented a variety of strains, which suggests that serotype Enteritidis organisms representing different genomic groups are circulating in England. In conclusion, geographical and animal origins of Salmonella serotype Enteritidis isolates may have a considerable influence on selecting the best typing strategy for individual programs, and a single method cannot be relied on for discriminating between strains.

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Serological typing of Escherichia coli O antigens is a well-established method used for differentiation and identification of O serotypes commonly associated with disease. In this feasibility study, we have developed a novel somatic antibody-based miniaturized microarray chip, using 17 antisera, which can be used to detect bound whole-cell E. coli antigen with its corresponding immobilized antibody, to assess the feasibility of this approach. The chip was tested using the related 17 control strains, and the O types found by the microarray chip showed 100% correlation with the O types found by conventional typing. A blind trial was performed in which 100 E. coli isolates that had been O serotyped previously by the conventional assay were tested by the array approach. Overall, the O serotypes of 88% of isolates were correctly identified by the microarray method. For several isolates, ambiguity of O-type designation by microarray arose due to increased sensitivity of this method, allowing signal intensities of cross-reactions to be quantified. Investigation of discrepancies between conventional and microarray O serotyping indicated that some isolates upon storage had become untypeable and, therefore, gave poor signal intensity when tested by the microarray or retested by conventional means. For all 20 serotype O26 and O157 isolates, the apparent discrepancy in O serotyping was analyzed further by a third independent test, which confirmed the microarray results. Therefore, the use of miniaturized protein arrays increases the speed and efficiency of O serotyping in a cost-effective manner, and these preliminary findings suggest the microarray approach may have a higher accuracy than those of traditional O-serotyping methods.

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Numerous Building Information Modelling (BIM) tools are well established and potentially beneficial in certain uses. However, issues of adoption and implementation persist, particularly for on-site use of BIM tools in the construction phase. We describe an empirical case-study of the implementation of an innovative ‘Site BIM’ system on a major hospital construction project. The main contractor on the project developed BIM-enabled tools to allow site workers using mobile tablet personal computers to access design information and to capture work quality and progress data on-site. Accounts show that ‘Site BIM’, while judged to be successful and actively supporting users, was delivered through an exploratory and emergent development process of informal prototyping. Technical IT skills were adopted into the construction project through personal relationships and arrangements rather than formal processes. Implementation was driven by construction project employees rather than controlled centrally by the corporate IT function.

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As wind generation increases, system impact studies rely on predictions of future generation and effective representation of wind variability. A well-established approach to investigate the impact of wind variability is to simulate generation using observations from 10 m meteorological mast-data. However, there are problems with relying purely on historical wind-speed records or generation histories: mast-data is often incomplete, not sited at a relevant wind generation sites, and recorded at the wrong altitude above ground (usually 10 m), each of which may distort the generation profile. A possible complimentary approach is to use reanalysis data, where data assimilation techniques are combined with state-of-the-art weather forecast models to produce complete gridded wind time-series over an area. Previous investigations of reanalysis datasets have placed an emphasis on comparing reanalysis to meteorological site records whereas this paper compares wind generation simulated using reanalysis data directly against historic wind generation records. Importantly, this comparison is conducted using raw reanalysis data (typical resolution ∼50 km), without relying on a computationally expensive “dynamical downscaling” for a particular target region. Although the raw reanalysis data cannot, by nature of its construction, represent the site-specific effects of sub-gridscale topography, it is nevertheless shown to be comparable to or better than the mast-based simulation in the region considered and it is therefore argued that raw reanalysis data may offer a number of significant advantages as a data source.

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Over the next few decades, it is expected that increasing fossil fuel prices will lead to a proliferation of energy crop cultivation initiatives. The environmental sustainability of these activities is thus a pressing issue—particularly when they take place in vulnerable regions, such as West Africa. In more general terms, the effect of increased CO2 concentrations and higher temperatures on biomass production and evapotranspiration affects the evolution of the global hydrological and carbon cycles. Investigating these processes for a C4 crop, such as sugarcane, thus provides an opportunity both to extend our understanding of the impact of climate change, and to assess our capacity to model the underpinning processes. This paper applies a process-based crop model to sugarcane in Ghana (where cultivation is planned), and the São Paulo region of Brazil (which has a well-established sugarcane industry). We show that, in the Daka River region of Ghana, provided there is sufficient irrigation, it is possible to generate approximately 75% of the yield achieved in the São Paulo region. In the final part of the study, the production of sugarcane under an idealized temperature increase climate change scenario is explored. It is shown that doubling CO2 mitigates the degree of water stress associated with a 4 °C increase in temperature.