Solitary wave propagation and steering through light-induced refractive potentials

The steering of a self-guided beam in a dye-doped nematic liquid crystal caused by an external illumination (control beam) that induces changes in the refractive index of the medium is theoretically analyzed. The interaction between the control beam and the dye molecules modifies the anchoring of the nematic molecules, so changing the director orientation in the bulk of the medium. Beam evolution is investigated by use of a modulation theory approach. It is found that the beam trajectory is independent of the beam profile, as long as this profile is self-similar. Solutions obtained from the modulation theory approach are in excellent agreement with numerical solutions

AIDS communication

Information and Communication for DevelopmentAndrew Skuse, Fiona Powe

The photopic negative response in autism spectrum disorder

Background: Visual function can be atypical in autism spectrum disorder and structural imaging of the ganglion cell layers has been reported to differ in these individuals. Therefore, we sought to investigate if the photopic negative response of the full field electroretinograms, a measure of ganglion cell function, could help explain the visual perceptual differences in autism spectrum disorder and support the structural changes observed. / Methods: Participants (n = 55 autism spectrum disorder, aged 5.4–26.7 years) and control (n = 87, aged 5.4–27.3 years) were recruited for the study. Full-field light-adapted electroretinograms using a Troland protocol with 10 flash strengths from −0.367 to 1.204 log photopic cd.s.m−2 were recorded in each eye. The photopic negative response amplitudes at Tmin and at t = 72 ms were compared between groups along with the a- and b-wave values. / Results: There were no significant interactions between groups for the Photopic Negative Response measures of amplitude or time (p > 0.30). There was a group interaction between groups and flash strengths for the b-wave amplitude as previously reported (p < 0.001). / Conclusion: The photopic negative response results suggest that there are no significant differences in the summed retinal ganglion cell responses produced by a full-field stimulus

The negative impact of global health worker migration, and how it can be addressed

International migration of healthcare workers is well established and has become a means of maintaining service quality in many high income countries. In recent years, there has been a dramatic increase in recruitment of health personnel who have been trained abroad, including from the poorest countries in the world. In this article, using General Medical Council (GMC) data, we chart the growth in numbers of international staff working in the United Kingdom, where since 2018, over half of all new GMC registrations have been of doctors trained abroad. There is evidence that this migration of health staff results in poorer health service provision in low and middle income countries, as well as substantial economic impacts in these countries that have invested in training their health workforce. Recruiting governments have argued that remittances compensate for the loss of personnel, and that training opportunities can enable skills transfer to countries with weaker health systems. However, we found that the costs to the source countries dwarfed remittances, and that only a tiny fraction of people who move to take up posts in wealthier countries ever return to their countries of origin to work. We conclude that in addition to the investment in health systems (and workforce development) in low and middle income countries as part of Official Development Assistance for Health, there is an urgent need to increase training of nurses and doctors so that damaging migration is no longer relied upon to fill gaps in healthcare personnel

Lessons Learned from the First Year Implementation of a Two-Track, Reformed Introductory Biology Course

The design, implementation and assessment of a novel, two-track, reformed introductory biology sequence are described in this paper. Course reform was based on the recommendations by the 2009 Vision & Change report from AAAS. Both tracks were based on guided inquiry, with an emphasis on constructivist pedagogy. One track included only students entering college with Advanced Placement Biology credit (N=24), who were given a studio style course that focused on the investigation of the phenomenon of “vanishing amphibians,” from molecules to ecosystems, over the entire year. The other track included the remaining students (N=68), who received more direct content instruction but through the use of numerous student-centered, active learning methods. The “AP Scholars” section entered with higher and more consistent levels of prior knowledge, but both sections made identical normalized learning gains and expressed satisfaction with the course, particularly the reformed aspects. The “AP Scholars” identified strongly as scientists and enjoyed the investigative nature of the course. The two-track course is now in its second year, and changes are being made in accordance with the lessons learned from the first year. This two-track system could serve as a model for other institutions looking to change their introductory biology sequence

Radio broadcasting for health: a decision maker's guide

Information and Communication for DevelopmentAndrew Skuse, Nadia Butler, Fiona Powe, Nicola Woods, Mary Myers, Nicola Harford, Heather Budge-Reid and Gordan Ada

Mental health and behavioural problems in children with XXYY: a comparison with intellectual disabilities

Background The phenotype of children with XXYY has predominantly been defined by comparison to other sex chromosome aneuploidies trisomies affecting male children; however, the intellectual ability of children with XXYY is lower than children with other sex chromosome aneuploidies trisomies. It is not known to what extent the phenotype identified to date is specific to XXYY, rather than a reflection of lower IQ. This study evaluates the mental health and behaviour of children with XXYY, in comparison to children with intellectual disabilities of heterogeneous genetic origin. Methods Fifteen children with XXYY and 30 controls matched for age (4–14 years), sex and intellectual ability were ascertained from the IMAGINE ID study. IMAGINE ID participants have intellectual disabilities due to genetic anomalies confirmed by National Health Service Regional Genetic Centre laboratories. The mental health and behaviour of participants was examined with the Development and Well‐being Assessment and the Strengths and Difficulties Questionnaire. Results Children with XXYY experienced significantly more frequent and intense temper outbursts than the control group. Conclusion Our results suggest that temper outbursts may be specifically associated with the XXYY phenotype. These problems have a significant impact on the daily lives of boys with XXYY and their families. It is crucial to ensure that families are well supported to manage these difficulties

PIM-1 membranes containing POSS - graphene oxide for CO2 separation

PIM-1 mixed matrix membranes (MMMs) were fabricated with polyhedral oligomeric silsesquioxane (POSS) and graphene oxide (GO) functionalized with POSS (GO-POSS), and tested for CO2/N2 (single gas) and CO2/CH4 (1:1, v:v gas mixture). The CO2 permeability of the best performing fresh MMM (containing 0.05 wt% GO-POSS) was ~ 12000 Barrer, which is 69% higher than that of the neat PIM-1 membrane, with about the same selectivity (CO2/CH4 selectivity ~ 12 and CO2/N2 selectivity ~ 20). In both cases, the gas separation data surpass the 2008 Robeson upper bound. In addition to the initial CO2 permeability enhancement, the use of GO-POSS is an efficient strategy to slow down physical aging. The MMM at a filler loading of 0.75 wt% showed less than half of the reduction in CO2 permeability than the neat PIM-1 membrane 160 days after preparation (26% for the MMM vs 58% for the purely polymeric one). © 2022 The Author(s