Limitations for change detection in multiple Gabor targets

We investigate the limitations on the ability to detect when a target has changed, using Gabor targets as simple quantifiable stimuli. Using a partial report technique to equalise response variables, we show that the log of the Weber fraction for detecting a spatial frequency change is proportional to the log of the number of targets, with a set-size effect that is greater than that reported for visual search. This is not a simple perceptual limitation, because pre-cueing a single target out of four restores performance to the level found when only one target is present. It is argued that the primary limitation on performance is the division of attention across multiple targets, rather than decay within visual memory. However in a simplified change detection experiment without cueing, where only one target of the set changed, not only was the set size effect still larger, but it was greater at 2000 msec ISI than at 250 msec ISI, indicating a possible memory component. The steepness of the set size effects obtained suggests that even moderate complexity of a stimulus in terms of number of component objects can overload attentional processes, suggesting a possible low-level mechanism for change blindness

Cluster randomised trials in the medical literature: two bibliometric surveys

Background: Several reviews of published cluster randomised trials have reported that about half did not take clustering into account in the analysis, which was thus incorrect and potentially misleading. In this paper I ask whether cluster randomised trials are increasing in both number and quality of reporting. Methods: Computer search for papers on cluster randomised trials since 1980, hand search of trial reports published in selected volumes of the British Medical Journal over 20 years. Results: There has been a large increase in the numbers of methodological papers and of trial reports using the term 'cluster random' in recent years, with about equal numbers of each type of paper. The British Medical Journal contained more such reports than any other journal. In this journal there was a corresponding increase over time in the number of trials where subjects were randomised in clusters. In 2003 all reports showed awareness of the need to allow for clustering in the analysis. In 1993 and before clustering was ignored in most such trials. Conclusion: Cluster trials are becoming more frequent and reporting is of higher quality. Perhaps statistician pressure works

Assessment of the food available to cape anchovy during their spawning season

The Cape anchovy Engraulis capensis spawns serially between September and February each year on the western Agulhas Bank, South Africa. Food availability in terms of copepod biomass is important for successfulspawning and subsequent recruitment. This note investigates the variability within a spawning season (1993/94 and 1994/95) of copepod biomass on the western Bank and demonstrates that the food available to the Capeanchovy cannot be adequately assessed by a single mid-season estimate, as was the previous sampling strategy. The mid-season estimate of food availability failed to reveal important fluctuations, such as the small biomass of copepods in January 1994, which contributed to the early cessation of spawning and subsequent poor recruitment in 1994. A strategy, based on monthly sampling, is recommended for future sampling programmes

Reproducibility of two, three, four and five 24-hour recalls in peri-urban African adolescents in the North West province

Background: The objective was to determine the reproducibility of two, three, four and five repeated 24-hour recalls among peri-urban African adolescents.Method: A prospective study design was used within the multidisciplinary PhysicaL Activity in the Young (PLAY) study. Eighty-seven Grade 9 learners (59 girls and 28 boys, aged 10-18 years) with a mean age of 14.7 ± 1.5 years, who had completed five 24-hour recalls, were investigated. The learners were from Seiphemelo Secondary School in Ikageng, a peri-urban area in the North West province of South Africa.Reproducibility coefficients (RCs) and 95% confidence intervals (CIs) were calculated, using the intraclass correlation coefficient formula for transformed values of selected nutrients and food groups, for two, three, four and five repeated 24-hour recalls. The RCs and 95% CIs were compared in order to identify the optimum number of 24-hour recalls to give the best reproducibility results.Results: The RCs were nutrient- and food-group sensitive and ranged from 0.25 (riboflavin) to 0.6 (carbohydrate). Although differences were not statistically significant, RCs for four and five 24-hour recalls were higher than those obtained for two and three 24-hour recalls. For most nutrients and food groups, four 24-hour recalls gave the highest RCs, with non-significant differences overall between the four and five 24-hour recalls.Conclusion: The results suggest that four 24-hour recalls would be sufficient to provide acceptable reproducibility of reported food group and nutrient intakes among peri-urban African adolescents.Keywords: adolescents, dietary assessment, reproducibility, 24-hour recalls, North West, peri-urba

TopBP1 contains transcriptional regulatory domains and regulates gene pathways involved in breast cancer

No abstract available

Oilseed rape (Brassica napus) as a resource for farmland insect pollinators: quantifying floral traits in conventional varieties and breeding systems

This is the final version of the article. Available from the publisher via the DOI in this record.Oilseed rape (OSR; Brassica napus L.) is a major crop in temperate regions and provides an important source ofnutrition to many of the yield-enhancing insect flower visitors that consume floral nectar. The manipulation ofmechanisms that control various crop plant traits for the benefit of pollinators has been suggested in the bid toincrease food security, but little is known about inherent floral trait expression in contemporary OSR varieties orthe breeding systems used in OSR breeding programmes. We studied a range of floral traits in glasshouse-grown, certified conventional varieties of winter OSR to test for variation among and within breeding systems.We measured 24-h nectar secretion rate, amount, concentration and ratio of nectar sugars per flower, and sizesand number of flowers produced per plant from 24 varieties of OSR representing open-pollinated (OP), genicmale sterility (GMS) hybrid and cytoplasmic male sterility (CMS) hybrid breeding systems. Sugar concentrationwas consistent among and within the breeding systems; however, GMS hybrids produced more nectar and moresugar per flower than CMS hybrid or OP varieties. With the exception of ratio of fructose/glucose in OP vari-eties, we found that nectar traits were consistent within all the breeding systems. When scaled, GMS hybridsproduced 1.73 times more nectar resource per plant than OP varieties. Nectar production and amount of nectarsugar in OSR plants were independent of number and size of flowers. Our data show that floral traits of glass-house-grown OSR differed among breeding systems, suggesting that manipulation and enhancement of nectarrewards for insect flower visitors, including pollinators, could be included in future OSR breeding programmes.This work was fundedby the BBSRC, including support from an Insect Pollinators Ini-tiative grant awarded to GAW (BB/I000968/1) that was jointlyfunded by the BBSRC, NERC, the Wellcome Trust, Defra, andthe Scottish Government. Support was also received from HighWycombe Beekeepers’ Association. Rothamsted Researchreceives strategic funding from the Biotechnology and BiologicalSciences Research Council (BBSRC) of the UK

Novel semiconducting iron–quinizarin metal–organic framework for application in supercapacitors^*

We present conductivity data for a newly synthesised metal organic framework FeQ, Fe(C14H6O4).H2O demonstrating significant electronic transport. The electrical conductivity of the material is expected to be through the π-π interaction of the ligand- quinizarin and is measured to be 1.73 × 10-2 Scm-1. Its potential role as supercapacitor electrodes is discussed

Changes in the use of coronary artery revascularization procedures in the Department of Veterans Affairs, the National Hospital Discharge Survey, and the Nationwide Inpatient Sample, 1991–1999

BACKGROUND: There have been dramatic increases in the number of coronary artery bypass surgeries (CABS) and percutaneous coronary interventions (PCI) performed during the last decade. Whether this finding is true for revascularization procedures performed in Department of Veterans Affairs (VA) medical centers is the subject of this paper. METHODS: This study compared the number of revascularization procedures and rates of use in the VA, the National Hospital Discharge Survey, and the Nationwide Inpatient Sample. Included were men who underwent isolated CABS and/or PCI, including stenting, between 1991 and 1999, although data for the Nationwide Inpatient Sample were available only between 1993 and 1997. Age adjusted use rates were calculated with the direct method of standardization. RESULTS: The percent of users of VA healthcare 75 years and older increased from 10% in 1991 to 20% in 1999. In the VA, the number of isolated CABS declined from 6227 in 1991 to 6147 in 1999, whereas age adjusted rates declined from 167.6 per 100,000 in 1991 to 107.9 per 100,000 in 1999. In the 2 national surveys, both the estimated numbers of procedures and use rates increased over time. In all 3 settings, there were increases in both numbers and rate of PCI from 1993, although in the VA, use rates decreased from 191.2 per 100,000 in 1996 to 139.7 per 100,000 in 1999. VA use rates for both CABS and PCI were lower than those in the 2 national surveys. CONCLUSION: Age adjusted rates of CABS and PCI were lower in the VA than in 2 national surveys. Since 1996, there has been a decrease in the rate of use of revascularization procedures in the VA

'I found myself a despicable being!':Medical students face disturbing moral dilemmas

CONTEXT: The psychological realm of medical students` moral experiences is explored tangentially in medical education literature, often in the context of ethics or professionalism education. This study deepens our understanding by (1) investigating the nature of moral dilemmas experienced at the onset of clinical practice, (2) exploring students` emotional response to these dilemmas, and (3) examining how students perceive the influence of these dilemmas on their professional development. METHODS: This is a cross-sectional qualitative study carried out in 2017 that applied Thematic Template Analysis to individual interviews performed with last-year medical students. The interviews followed the drawing of a Rich Picture representing moral dilemmas experienced by medical students at the onset of clinical practice. RESULTS: Moral dilemmas have four intertwined dimensions. The first relates to students` struggle to prioritize, balance and apply conflicting moral values; the second comprises the clash between students` inner motivation and the external constraints that limit the moral action; the third refers to the conflict between students' current attitudes with the desired/idealized attitudes of the doctor they intend to become; the forth corresponds to weighting conflicting ethical principles during the moral decision. Students` emotional responses are intense, long-lasting, and with a remarkable residue effect, particularly when the moral decision does not align with their moral beliefs. Moral dilemmas are impactful experiences that affect the professional development of medical students and can culminate in both detachment or growth in moral courage. CONCLUSION: Moral dilemmas are memorable, complex, and emotionally intense experiences that impact the professional development of medical students. Understanding students` moral dilemmas can help educators to devise pedagogical activities to anticipate and reflect on these experiences. These activities should happen under the guidance of a non-judgmental facilitator, capable of listening and legitimating students' thoughts and feelings while providing insights to nurture their professional development