Sequence effects in categorization of simple perceptual stimuli

Categorization research typically assumes that the cognitive system has access to a (more or less noisy) representation of the absolute magnitudes of the properties of stimuli and that this information is used in reaching a categorization decision. However, research on identification of simple perceptual stimuli suggests that people have very poor representations of absolute magnitude information and that judgments about absolute magnitude are strongly influenced by preceding material. The experiments presented here investigate such sequence effects in categorization tasks. Strong sequence effects were found. Classification of a borderline stimulus was more accurate when preceded by a distant member of the opposite category than by a distant member of the same category. It is argued that this category contrast effect cannot be accounted for by extant exemplar or decision-bound models of categorization. The effect suggests the use of relative magnitude information in categorization. A memory and contrast model illustrates how relative magnitude information may be used in categorization

Laser ablation of Diamond and Genesis concentrator target material

UV laser ablations of CVD diamond using two wavelengths of radiation (266 nm and 213 nm) have been compared. The impetus for this work is the 2004 return of Genesis and extraction of solar-wind oxygen implanted in diamond

Associations between a one-shot delay discounting measure and age, income, education and real-world impulsive behavior

There has been discussion over the extent to which delay discounting – as prototypically shown by a preference for a smaller-sooner sum of money over a larger-later sum – measures the same kind of impulsive preferences that drive non-financial behavior. To address this issue, a dataset was analyzed containing 42,863 participants’ responses to a single delay-discounting choice, along with self-report behaviors that can be considered as impulsive. Choice of a smaller-sooner sum was associated with several demographics: younger age, lower income, and lower education; and impulsive behaviors: earlier age of first sexual activity and recent relationship infidelity, smoking, and higher body mass index. These findings suggest that at least an aspect of delay discounting preference is associated with a general trait influencing other forms of impulsivity, and therefore that high delay discounting is another form of impulsive behavior

Effective behaviour change techniques in the prevention and management of childhood obesity

Rates of childhood obesity are increasing, and it is essential to identify the active components of interventions aiming to prevent and manage obesity in children. A systematic review of behaviour change interventions was conducted to find evidence of behaviour change techniques (BCTs) that are most effective in changing physical activity and/or eating behaviour for the prevention or management of childhood obesity. An electronic search was conducted for randomised controlled trials published between January 1990 and December 2009. Of 4309 titles and abstracts screened, full texts of 135 articles were assessed, of which 17 published articles were included in this review. Intervention descriptions were coded according to the behaviour-specific CALO-RE taxonomy of BCTs. BCTs were identified and compared across obesity management (n=9) vs prevention (n=8) trials. To assess the effectiveness of individual BCTs, trials were further divided into those that were effective (defined as either a group reduction of at least 0.13 body mass index (BMI) units or a significant difference in BMI between intervention and control groups at follow-up) vs non-effective (reported no significant differences between groups). We reliably identified BCTs utilised in effective and non-effective prevention and management trials. To illustrate the relative effectiveness of each BCT, effectiveness ratios were calculated as the ratio of the number of times each BCT was a component of an intervention in an effective trial divided by the number of times they were a component of all trials. Results indicated six BCTs that may be effective components of future management interventions (provide information on the consequences of behaviour to the individual, environmental restructuring, prompt practice, prompt identification as role model/position advocate, stress management/emotional control training and general communication skills training), and one that may be effective in prevention interventions (prompting generalisation of a target behaviour). We identified that for management trials, providing information on the consequences of behaviour in general was a feature of non-effective interventions and for prevention trials, providing information on the consequences of behaviour in general, providing rewards contingent on successful behaviour and facilitating social comparison were non-effective. To design effective behaviour change programmes for the prevention and management of childhood obesity, we would recommend utilising the BCTs identified as effective in this review. The impact on intervention effectiveness of combining BCTs should be the topic of further research

Educational needs of Australian rural and remote doctors for intermediate obstetric ultrasound and emergency medicine ultrasound

Introduction: The aim of this research was to determine the educational needs of Australian rural and remote doctors for intermediate obstetric ultrasound and emergency medicine ultrasound. The main research questions were: what educational topics would rural and remote doctors prefer to learn about in intermediate obstetric ultrasound and emergency medicine ultrasound, and what were those doctors' preferred methods of delivery for an ultrasound education program. Method: A self-administered postal questionnaire containing a pre-paid return envelope was mailed to 344 Australian rural and remote doctors in December 2003. Results: 107 completed questionnaires were returned, giving a response rate of 32.7%. This was after the denominator was adjusted for the 17 doctors whose letters were returned to sender. The respondents included 23 (21.5%) female and 84 (78.5%) male doctors. Eighty doctors (74.8%) stated that they used ultrasound, and 27 (25.2%) said they did not. Seventy-seven (72%) indicated they had previously participated in some ultrasound education and training. The respondents stated that their main areas of educational need in intermediate obstetric ultrasound were ectopic pregnancy (76.6%), miscarriage (72%), intrauterine growth restriction (65.4%), transvaginal scanning (47.7%), detecting fetal abnormalities (47.7%) and morphology scanning at 18-20 weeks (41.1%). The main areas of educational need in emergency medicine ultrasound were focused abdominal sonography in trauma (63.5%), detecting foreign bodies (40.2%), gynecological ultrasound (39.2%), gall bladder and biliary tract (37.4%), abdominal aortic aneurysm (32.7%) and trauma bleeding (31.7%). Conclusion: Australian rural and remote doctors are using ultrasound technology to improve the clinical investigation and diagnosis of a large variety of clinical conditions in their family medical practices. This paper describes the results of research into the educational needs of this target group of doctors

Replacing sugary snacks with fruit, nuts and seeds at nurses’ stations within a uk oncology unit: A pilot intervention study

Aim-This real-world service intervention study evaluated NHS staff weight and subjective happiness over a three-month period, by replacing processed, sugary foodstuffs with fruit, nuts and seeds. Method-Forty four staff at the Primrose Oncology Unit, Bedford Hospital, volunteered to abstain from cakes, biscuits, sweets, sugary drinks and chocolates whilst at work between June 2019 and September 2019. Participants’ weight and subjective happiness scores were recorded at baseline, three months (completion) and five months (post-completion). Fresh and dried fruit, and bags of raw nuts and seeds were made available to all staff (including those not participating). Participants resumed their usual diet outside of working hours. One hundred consecutive patients attending the department during the intervention were asked whether removing sugary food from public view was a positive move and whether it would have a likely influence on their future eating habits. Results-At five months, twenty (46%) participants lost weight >1kg (average 3.01 kg), seven participants gained >1kg (average 2.23 kg), and 17 remained the same weight (T-test p1kg weight, average happiness score increased from 21.54 to 23.75 (+9.3%), p1 kg weight, average happiness score decreased from 22.28 to 21.43 (-3.8%), p1kg compared to those gaining >1kg in weight p< 0.001). 94 (94%) patients indicated that this initiative gave a good impression and ninety seven (97%) indicated that the initiative would encourage them to reduce sugar in their own diet. Conclusion-The results demonstrated a statistically significant reduction in weight loss and increase in mood in just under half of the participants. Whilst this level of weight loss was similar to the best designed weight loss programmes, a larger study is required to validate these results

Evolution in a Changing Environment

We propose a simple model for genetic adaptation to a changing environment, describing a fitness landscape characterized by two maxima. One is associated with “specialist” individuals that are adapted to the environment; this maximum moves over time as the environment changes. The other maximum is static, and represents “generalist” individuals not affected by environmental changes. The rest of the landscape is occupied by “maladapted” individuals. Our analysis considers the evolution of these three subpopulations. Our main result is that, in presence of a sufficiently stable environmental feature, as in the case of an unchanging aspect of a physical habitat, specialists can dominate the population. By contrast, rapidly changing environmental features, such as language or cultural habits, are a moving target for the genes; here, generalists dominate, because the best evolutionary strategy is to adopt neutral alleles not specialized for any specific environment. The model we propose is based on simple assumptions about evolutionary dynamics and describes all possible scenarios in a non-trivial phase diagram. The approach provides a general framework to address such fundamental issues as the Baldwin effect, the biological basis for language, or the ecological consequences of a rapid climate change