The structure of random discrete spacetime

The usual picture of spacetime consists of a continuous manifold, together with a metric of Lorentzian signature which imposes a causal structure on the spacetime. A model, first suggested by Bombelli et al., is considered in which spacetime consists of a discrete set of points taken at random from a manifold, with only the causal structure on this set remaining. This structure constitutes a partially ordered set (or poset). Working from the poset alone, it is shown how to construct a metric on the space which closely approximates the metric on the original spacetime manifold, how to define the effective dimension of the spacetime, and how such quantities may depend on the scale of measurement. Possible desirable features of the model are discussed

Using pedometers as motivational tools : are goals set in steps more effective than goals set in minutes for increasing walking?

Background Pedometers are popular devices that measure walking steps. There has been a recent surge in promoting the pedometer as a motivational tool to increase walking. However, little empirical evidence exists to support this suggestion. This study examined the effectiveness of a pedometer as a motivational tool to increase walking. 50 participants (7 men and 43 women, mean age (SD) 40.16 (8.81) years, range 25-61 years) were randomly assigned to either an intervention group who followed a four-week walking programme with goals set in steps (using an open pedometer for feedback) or a comparison group who followed an equivalent four-week walking programme with goals set in minutes. Participants had step-counts recorded at baseline, weeks 1, 2, 3, 4, and at weeks 16 and 52 for follow-up. Both groups significantly increased step-counts from baseline to week 4 with no significant difference between groups. However, a significantly greater number of participants in the intervention group (77%) compared with the comparison group (54%) achieved their week 4 goals (p=0.03). There was no significant change in step-counts from week 4 to week 16. There was a significant decrease from week 16 to week 52. In the short term, both goals set in minutes and goals set in steps using a pedometer may be effective at promoting walking. In the long term, additional support may be required to sustain increases in walking

Do patients who die from an alcohol-related condition ‘drift’ into areas of greater deprivation? Alcohol-related mortality and health selection theory in Scotland

Background: Health selection has been proposed to explain the patterning of alcohol-related mortality by area deprivation. This study investigated whether persons who die from alcohol-related conditions are more likely to experience social drift than those who die from other causes. Methods: Deaths recorded in Scotland (2013, >21 years) were coded as ‘alcohol-related’ or ‘other’ and by deprivation decile of residence at death. Acute hospital admissions data from 1996 to 2012 were used to provide premortality deprivation data. χ² tests estimated the difference between observed and expected alcohol-related deaths by first Scottish Index of Multiple Deprivation (SIMD) decile and type of death. Logistic regression models were fitted using type of death as the outcome of interest and change in SIMD decile as the exposure of interest. Results: Of 47 012 deaths, 1458 were alcohol-related. Upward and downward mobility was observed for both types of death. An estimated 31 more deaths than expected were classified ‘alcohol-related’ among cases whose deprivation score decreased, while 204 more deaths than expected were classified ‘alcohol-related’ among cases whose initial deprivation ranking was in the four most deprived deciles. Becoming more deprived and first deprivation category were both associated with increased odds of type of death being alcohol-related after adjusting for confounders. Conclusion: This study suggests that health selection appears to contribute less to the deprivation gradient in alcohol-related mortality in Scotland than an individual’s initial area deprivation category

Marking machinima : a case study in assessing student use of a Web 2.0 technology

The model of learning best suited to the future may be one which sees learning as the process of managing the different kinds of participation an individual might have in complex social systems. Learning capability and engagement is thus dependent on the relationship between an individual identity and social systems. We report on the incorporation of machinima, a Web 2.0 technology, as part of an interdisciplinary and collaborative project where the focus is not on the mastery of the tools or the acquisition of predetermined knowledge, but on the development of learning engagement. We provide the case study of a pilot project involving students across two Arts disciplines collaborating via the game, World of Warcraft, to produce an animated adaptation of one of Geoffrey Chaucer\u27s Canterbury Tales. Their contributions were differently assessed according to the pre-existing requirements of their home disciplines. We argue that the assessment in such projects, in conjunction with innovations and experimentation with Web 2.0 technologies, should shift from an emphasis on product to process. We believe that this has a sound pedagogical and theoretical foundation, and also fits better with the increasingly digitalised, unfixed and interdisciplinary world that students will face on graduation. <br /

Disease activity and cognition in rheumatoid arthritis : an open label pilot study

Acknowledgements This work was supported in part by NIHR Newcastle Biomedical Research Centre. Funding for this study was provided by Abbott Laboratories. Abbott Laboratories were not involved in study design; in the collection, analysis and interpretation of data; or in the writing of the report.Peer reviewedPublisher PD

A change in temperature modulates defence to yellow (stripe) rust in wheat line UC1041 independently of resistance gene Yr36

Background Rust diseases are of major importance in wheat production worldwide. With the constant evolution of new rust strains and their adaptation to higher temperatures, consistent and durable disease resistance is a key challenge. Environmental conditions affect resistance gene performance, but the basis for this is poorly understood. Results Here we show that a change in day temperature affects wheat resistance to Puccinia striiformis f. sp tritici (Pst), the causal agent of yellow (or stripe) rust. Using adult plants of near-isogenic lines UC1041 +/- Yr36, there was no significant difference between Pst percentage uredia coverage in plants grown at day temperatures of 18°C or 25°C in adult UC1041 + Yr36 plants. However, when plants were transferred to the lower day temperature at the time of Pst inoculation, infection increased up to two fold. Interestingly, this response was independent of Yr36, which has previously been reported as a temperature-responsive resistance gene as Pst development in adult UC1041 -Yr36 plants was similarly affected by the plants experiencing a temperature reduction. In addition, UC1041 -Yr36 plants grown at the lower temperature then transferred to the higher temperature were effectively resistant and a temperature change in either direction was shown to affect Pst development up to 8 days prior to inoculation. Results for seedlings were similar, but more variable compared to adult plants. Enhanced resistance to Pst was observed in seedlings of UC1041 and the cultivar Shamrock when transferred to the higher temperature. Resistance was not affected in seedlings of cultivar Solstice by a temperature change in either direction. Conclusions Yr36 is effective at 18°C, refining the lower range of temperature at which resistance against Pst is conferred compared to previous studies. Results reveal previously uncharacterised defence temperature sensitivity in the UC1041 background which is caused by a change in temperature and independently of Yr36. This novel phenotype is present in some cultivars but absent in others, suggesting that Pst defence may be more stable in some cultivars than others when plants are exposed to varying temperatures

Exploratory studies to inform full-scale evaluations of complex public health interventions: the need for guidance

No abstract available