Phase-Conjugate Feedback Effects in Electrically Pumped Semiconductor Nano-Laser Arrays

An analysis is performed of the response of arrays of semiconductor nano-lasers to phase-conjugate optical feedback. A comparison is made of their response to conventional mirror feedback. It is shown that phase-conjugate feedback induces a quasi-periodic route to chaos. The impact of the Purcell-enhanced spontaneous emission, which is a salient feature of nano-lasers, is also delineated for both phase-conjugate and conventional mirror feedback

Evaluating microplastic trapping efficiency in seagrass meadows using hydraulic flume simulations

Microplastic (MP) pollution poses a significant environmental threat, with projections indicating a 50-fold increase in pollution levels by 2100. Seagrass meadows, important for carbon storage and sediment stabilisation, may also serve as a Nature-based Solution for MP pollution. Despite the well-documented presence of MPs in seagrass sediments, the efficiencies of MP capture by these habitats remain largely unexplored. In this study, hydraulic flume simulations were conducted to assess how different seagrass planting configurations influence MP trapping. The results indicate that meadows with random spatial distribution are 6 % more effective at trapping MPs under high concentrations compared to grid-patterned meadows, while lower planting densities enhance trapping efficiency by 14 %. These findings offer insights into optimising seagrass restoration efforts for mitigating MP pollution, and this highlights the need for further needed to understand the broader ecological implications of MP retention in these critical ecosystems

Age-dependent phenotypes of cognitive impairment as sequelae of SARS-CoV-2 infection

Cognitive changes associated with PASC may not be uniform across populations. We conducted individual-level pooled analyses and meta-analyses of cognitive assessments from eight prospective cohorts, comprising 2,105 patients and 1,432 controls from Argentina, Canada, Chile, Greece, India, Italy, Russia, and the UK. The meta-analysis found no differences by country of origin. The profile and severity of cognitive impairment varied by age, with mild attentional impairment observed in young and middle-aged adults, but memory, language, and executive function impairment in older adults. The risk of moderate to severe impairment doubled in older adults. Moderately severe or severe impairment was significantly associated with infection diagnoses (chi-square = 26.57, p ≤ 0.0001) and the severity of anosmia (chi-square = 31.81, p ≤ 0.0001). We found distinct age-related phenotypes of cognitive impairment in patients recovering from COVID-19. We identified the severity of acute illness and the presence of olfactory dysfunction as the primary predictors of dementia-like impairment in older adults

Use of patient-centred outcome measures alongside the personal wheelchair budget process in NHS England: A mixed methods approach to exploring the staff and service user experience of using the WATCh and WATCh-Ad

Background and objective: Personal wheelchair budgets (PWBs) are offered to everyone in England eligible for a wheelchair provided through the National Health Service (NHS) to support their choice of equipment. The WATCh (Wheelchair outcomes Assessment Tool for Children) and related WATCh-Ad for adults are patient-centred outcome measures (PCOMs) developed to help individual users express their main outcome needs when obtaining a wheelchair and rate their satisfaction with subsequent outcomes after receiving their equipment. Use was explored in a real-world setting, aiming to produce guidance for use alongside the PWB process.Methods: Three wheelchair service provider organisations across four sites participated. Staff and users completed surveys about their experience of assessments using the WATCh and/or WATCh-Ad. Selected patients were interviewed after receipt of their equipment, and staff were interviewed after experiencing a number of assessments. Thematic analysis was undertaken using the tool, survey and interview data. Results of pre- and post-equipment provision were presented graphically.Results: Information on 75 assessments by 15 staff was obtained. Three-quarters of users or their carers rated the use of the tools in the assessment process as 'helpful' or 'very helpful'. Staff reported that the WATCh or WATCh-Ad had been considered 'useful' in developing individual care plans in around 1 in 3 cases and affected the prescription in 1 in 4 cases. Concerns were expressed about the length of time taken to administer the tools in clinic. However, some staff noted this reduced with more hands-on experience and by providing the tools to users in advance of the appointment.Conclusions: The WATCh and WATCh-Ad PCOMs are suitable for routine use by wheelchair service providers to assist the assessment process. It is recommended that tool materials are provided in advance to users/carers and that staff are allowed time to develop their ways of working with them

Probiotic colonization of Xenopus laevis skin causes short-term changes in skin microbiomes and gene expression

Probiotic therapies have been suggested for amelioration efforts of wildlife disease such as chytridiomycosis caused by Batrachochytrium spp. in amphibians. However, there is a lack of information on how probiotic application affects resident microbial communities and immune responses. To better understand these interactions, we hypothesized that probiotic application would alter microbial community composition and host immune expression in Xenopus laevis. Accordingly, we applied three amphibian-derived and anti-Batrachochytrium bacteria strains (two Pseudomonas spp., and one Stenotrophomonas sp.) to X. laevis in monoculture and also as a cocktail. We quantified microbial community structure using 16S rRNA gene sequencing. We also quantified genes involved in X. laevis immune responses using RT-qPCR and skin transcriptomics over one and three-week periods. All probiotic treatments successfully colonized X. laevis skin for three weeks, but with differential ASV sequence counts over time. Bacterial community and immune gene effects were most pronounced at week 1 post-probiotic exposure and decreased thereafter. All probiotic treatments caused initial changes to bacterial community alpha and beta diversity, including reduction in diversity from pre-exposure anti-Batrachochytrium bacterial ASV relative abundance. Probiotic colonization by Pseudomonas probiotic strain RSB5.4 reduced expression of regulatory T cell marker (FOXP3, measured with RT-qPCR) and caused the greatest gene expression changes detected by transcriptomics. Single bacterial strains and mixed cultures therefore altered amphibian microbiome-immune interactions. This work will help to improve our understanding of the role of the microbiome-immune interface underlying both disease dynamics and emergent eco-evolutionary processes

Scherzo I-III

ar gyfer clarinét, feiolin, sielo a phiano ar ôl darluniau tryptich gan yr artist Chris Holleyfor clarinet, violin , cello and piano after the tryptich paintings by artist Chris Holle

Factors Associated with Weight Change in Adults with Severe Mental Illness: Results from a Large Cross-Sectional Survey

Background/objectives: Individuals with severe mental illness (SMI) have a reduced life expectancy of 15-25 years. This is due to a number of modifiable and non-modifiable risk factors. Levels of overweight and obesity in this group are 1.8 times higher than in the general population and diet quality is poor. Excess weight is linked to a range of serious long-term physical and mental health conditions. This paper presents the findings of a large cross-sectional survey of adults living with SMI. The survey aimed to understand the current weight, weight gain and diet quality of this group and secondly, to explore the association between weight change, diet quality, antipsychotic medication and weight management. Methods: Five hundred and twenty-nine participants (58% male, mean age 49.3) living with SMI completed the survey. Results: Results showed 42% of the sample were living with obesity and almost half reported having gained 6kg or more at least once in their adult life. Overall, 6% of the sample reported eating no fruit or vegetables and the same proportion had the highest consumption of carbonated drinks. There was no difference by weight category. Those taking antipsychotic medication and currently managing their weight were more likely to experience weight gain or fluctuation. Conclusions: These results suggest that excess weight and poor diet quality are a major problem in adults with SMI and that current weight management provision is ineffective in addressing the specific needs of people living with SMI

Adjustable wind selectivity in shearwaters implies knowledge of the foraging landscape

Understanding the movements of highly mobile animals is challenging because of the many factors they must consider in their decision-making. Many seabirds, for example, are adapted to use winds to travel long distances at low energetic cost1,2,3 but also potentially benefit from targeting specific foraging hotspots.4,5,6 To investigate how an animal makes foraging decisions, given the inevitable trade-off between these factors, we tracked over 600 foraging trips of breeding Manx shearwaters (Puffinus puffinus; N = 218 individuals) using GPS accelerometers. By first uncovering the relationships between wind and the flapping effort put into flight, we show that shearwaters, while generally wind selective, adjust their wind selectivity, apparently balancing flight costs against the benefits of travel toward known targets. This is supported by a number of scenarios that alter the balance between maximizing flight efficiency and goal-oriented flight. First, shearwaters exhibit lower wind selectivity during homing movement when constrained to target-driven navigation toward the colony. Second, when wind speeds are low, flight costs vary little with travel direction, which shearwaters respond to by reducing wind selectivity in their outbound commutes, again favoring target-driven movement toward presumably memorized foraging areas. Finally, birds are also less wind selective during longer continuous periods of flight, presumably also associated with target-oriented movement. Our findings reveal how an animal’s foraging strategy can dynamically optimize the complex trade-off between efficient travel and accessing known foraging areas, implying the incorporation of prior knowledge of the cost-benefit landscape well beyond the range of what can be detected directly