3,888 research outputs found

    Buckling without bending: a new paradigm in morphogenesis

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    A curious feature of organ and organoid morphogenesis is that in certain cases, spatial oscillations in the thickness of the growing "film" are out-of-phase with the deformation of the slower-growing "substrate," while in other cases, the oscillations are in-phase. The former cannot be explained by elastic bilayer instability, and contradict the notion that there is a universal mechanism by which brains, intestines, teeth, and other organs develop surface wrinkles and folds. Inspired by the microstructure of the embryonic cerebellum, we develop a new model of 2d morphogenesis in which system-spanning elastic fibers endow the organ with a preferred radius, while a separate fiber network resides in the otherwise fluid-like film at the outer edge of the organ and resists thickness gradients thereof. The tendency of the film to uniformly thicken or thin is described via a "growth potential". Several features of cerebellum, +blebbistatin organoid, and retinal fovea morphogenesis, including out-of-phase behavior and a film thickness amplitude that is comparable to the radius amplitude, are readily explained by our simple analytical model, as may be an observed scale-invariance in the number of folds in the cerebellum. We also study a nonlinear variant of the model, propose further biological and bio-inspired applications, and address how our model is and is not unique to the developing nervous system.Comment: version accepted by Physical Review

    The Association Between Health Care Staff Engagement and Patient Safety Outcomes: A Systematic Review and Meta-Analysis

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    Objectives: Despite decades of research, improving health care safety remains a global priority. Individual studies have demonstrated links between staff engagement and care quality, but until now, any relationship between engagement and patient safety outcomes has been more speculative. This systematic review and meta-analysis therefore assessed this relationship and explored if the way these variables were defined and measured had any differential effect. Methods: After systematic searches of Medline, CINAHL, PsycInfo, Embase, Cochrane Library, and National Institute for Health Research Journals databases, narrative and random-effects meta-analyses were completed, with pooled effect sizes expressed as Pearson r. Results: Fourteen studies met the inclusion criteria, 11 of which were suitable for meta-analysis. Meta-analyses indicated a small but consistent, statistically significant relationship between staff engagement and patient safety (all outcomes; 11 studies; r = 0.22; 95% confidence interval [CI], 0.07 to 0.36; n = 30,490) and 2 patient safety outcome categories: patient safety culture (7 studies;r = 0.22; 95% CI, 0.01 to 0.41; n = 27,857) and errors/adverse events (4 studies;r = −0.20; 95% CI, −0.26 to −0.13; n = 2633). The specific approach to conceptualizing engagement did not affect the strength of the findings. Conclusions: This is the first review to demonstrate a significant relationship between engagement and both safety culture scores and errors/adverse events. Despite a limited and evolving evidence base, we cautiously conclude that increasing staff engagement could be an effective means of enhancing patient safety. Further research is needed to determine causality and clarify the nature of the staff engagement/patient safety relationship at individual and unit/workgroup levels

    A qualitative formative evaluation of a patient facing intervention to improve care transitions for older people moving from hospital to home

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    Background The Partners at Care Transitions (PACTs) intervention was developed to support older people's involvement in hospital to improve outcomes at home. A booklet, question card, record sheet, induction leaflet, and patient‐friendly discharge letter support patients to be more involved in their health and wellbeing, medications, activities of daily living and post‐discharge care. We aimed to assess intervention acceptability, identify implementation tools, and further develop the intervention. Methods This was a qualitative formative evaluation involving three wards from one hospital. We recruited 25 patients aged 75 years and older. Ward staff supported intervention delivery. Data were collected in wards and patients' homes, through semi‐structured interviews, observation, and documentary analysis. Data were analysed inductively and iteratively with findings sorted according to the research aims. Results Patients and staff felt there was a need for, and understood the purpose of, the PACT intervention. Most patients read the booklet but other components were variably used. Implementation challenges included time, awareness, and balancing intervention benefits against risks. Changes to the intervention and implementation included clarifying the booklet's messages, simplifying the discharge letter to reduce staff burden, and using prompts and handouts to promote awareness. Conclusion Patients and staff felt there was a need for, and understood the purpose of, the PACT intervention. Most patients read the booklet but other components were variably used. Implementation challenges included time, awareness, and balancing intervention benefits against risks. Changes to the intervention and implementation included clarifying the booklet's messages, simplifying the discharge letter to reduce staff burden, and using prompts and handouts to promote awareness

    Biodesalination: an emerging technology for targeted removal of Na+and Cl−from seawater by cyanobacteria

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    Although desalination by membrane processes is a possible solution to the problem of freshwater supply, related cost and energy demands prohibit its use on a global scale. Hence, there is an emerging necessity for alternative, energy and cost-efficient methods for water desalination. Cyanobacteria are oxygen-producing, photosynthetic bacteria that actively grow in vast blooms both in fresh and seawater bodies. Moreover, cyanobacteria can grow with minimal nutrient requirements and under natural sunlight. Taking these observations together, a consortium of five British Universities was formed to test the principle of using cyanobacteria as ion exchangers, for the specific removal of Na+ and Cl− from seawater. This project consisted of the isolation and characterisation of candidate strains, with central focus on their potential to be osmotically and ionically adaptable. The selection panel resulted in the identification of two Euryhaline strains, one of freshwater (Synechocystis sp. Strain PCC 6803) and one of marine origin (Synechococcus sp. Strain PCC 7002) (Robert Gordon University, Aberdeen). Other work packages were as follows. Genetic manipulations potentially allowed for the expression of a light-driven, Cl−-selective pump in both strains, therefore, enhancing the bioaccumulation of specific ions within the cell (University of Glasgow). Characterisation of surface properties under different salinities (University of Sheffield), ensured that cell–liquid separation efficiency would be maximised post-treatment, as well as monitoring the secretion of mucopolysaccharides in the medium during cell growth. Work at Newcastle University is focused on the social acceptance of this scenario, together with an assessment of the potential risks through the generation and application of a Hazard Analysis and Critical Control Points plan. Finally, researchers in Imperial College (London) designed the process, from biomass production to water treatment and generation of a model photobioreactor. This multimodal approach has produced promising first results, and further optimisation is expected to result in mass scaling of this process

    Tomonaga-Luttinger liquid parameters of magnetic waveguides in graphene

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    Electronic waveguides in graphene formed by counterpropagating snake states in suitable inhomogeneous magnetic fields are shown to constitute a realization of a Tomonaga-Luttinger liquid. Due to the spatial separation of the right- and left-moving snake states, this non-Fermi liquid state induced by electron-electron interactions is essentially unaffected by disorder. We calculate the interaction parameters accounting for the absence of Galilei invariance in this system, and thereby demonstrate that non-Fermi liquid effects are significant and tunable in realistic geometries

    Multiple meanings of resilience: Health professionals' experiences of a dual element training intervention designed to help them prepare for coping with error

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    Rationale, aims and objectives: Consistent data demonstrates negative psychological effects of caregiving on front-line health professionals. Evidence that psychological resilience factors can help minimize distress and the potential for low-cost interventions have created interest in resilience-based development programmes; yet evidence of perceived value amongst health professionals is lacking. This study explored health professionals' experiences and perceptions of a novel, resilience-based intervention designed to pro-actively prepare staff for coping with error; to investigate their perceptions of what resilience meant to them, the relevance of the intervention, and impact of participation on ability to cope with error. Methods: Semi-structured interviews 4-6 weeks post intervention with 23 randomly selected participants from seven cohorts (midwives, paediatricians, obstetricians/gynaecologists, paramedics) and trainees (physician associates, mammographers, sonographers). Thematic analysis of interview data. Findings: Participants reported various interpretations of, and a shift in perception regarding what the concept of psychological resilience meant to them and their practice. These included for example, resilience as a positive or negative concept and their awareness and response to a range of personal, organizational and system factors influencing personal resilience. They valued the prophylactic, clinically relevant, interactive and applied nature of the intervention; having developed and applied valuable skills beyond the context of involvement in error, noting that individuals needed to be willing to explore their own coping mechanisms and human fallibility to gain maximum benefit. There was also consensus that whilst proactively developing individual levelpsychological resilience is important, so too is addressing the organizational and system factors that affect staff resilience which are outside individual staff control. Conclusion: Enhancing resilience appears to be considered useful in supporting staff to prepare for coping with error and the wider emotional burden of clinical work, but such interventions require integration into wider system approaches to reduce the burden of clinical work for health professionals

    The views of children and young people on the use of silk garments for the treatment of eczema: a nested qualitative study within the CLOTHES randomised controlled trial

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    Background: Many children suffer with skin diseases, but to date, most dermatological research has been done ‘on’ rather than ‘with’ children; in this study we actively sought the experiences of children and young people. Atopic eczema (AE) is a chronic, itchy, inflammatory skin condition that affects around 20% of children and can impact on health and wellbeing for children and their families. The role of specialist clothing in the management of AE is poorly understood. Objectives: The aim of this study, which was nested in a randomised controlled trial was to qualitatively examine child participants’ experiences of using silk garments for the treatment of AE. Methods: Eighteen children aged 5-15, who took part in the CLOTHES trial, participated in age-appropriate individual interviews or focus groups. Results: Thematic analysis generated 4 themes directly related to the garments: i) expectations of the garments; ii) wearing the silk garments; iii) did they help? and iv) thoughts about the garments. The conclusions from this nested qualitative study are that: there was some limited improvement in eczema for some children but that the hoped for ‘miracle cure’ did not transpire. A mixed picture of knowledge, beliefs and experiences of using the silk garments emerged. Conclusion: Engaging children in the evaluation of the garments provided first hand nuanced insights that enhanced understanding of the CLOTHES study as a whole. This nested study demonstrates that children can and indeed want to be engaged in dermatological research in meaningful ways that add to our understanding of treatment options

    Low-cost carriers and airports: a complex relationship

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    In the last decades, low-cost carriers have generated several changes in the air market for both passengers and airports. Mainly for regional airports, low-cost carriers have represented an important opportunity to improve their connectivity levels and passenger traffic. Furthermore, many regional airports have become key factors to regenerate the local economy by improving accessibility and stimulating several markets, such as tourism. However, the relationship between low-cost carriers and airports is rather complex and the outcomes not always predictable. In order to analyse and understand better such relationship and its outcomes, this chapter discusses the main underlying factors identified in: relation with the regional air market (secondary/primary airports), balance of power (dominated/non-dominated airports) and industrial organisation (bases/non-bases). Starting from the proposed Relative Closeness Index, which combines yearly airport passengers and distance between airport pairs, a large sample of European airports is analysed. Then, a smaller sub-sample – which includes selected, significant case studies referring to mid-sized airports – is discussed in detail. Among the main findings, airports sharing their catchment area with others are in a very risky position, due to the potential mobility of LCCs, while geographically isolated airports in good catchment areas can better counterbalance the power of carriers

    Assessing the Association between Serum Ferritin, Transferrin Saturation, and C-Reactive Protein in Northern Territory Indigenous Australian Patients with High Serum Ferritin on Maintenance Haemodialysis

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    Copyright © 2017 SandawanaWilliam Majoni et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Objective. To determine the significance of high serum ferritin observed in Indigenous Australian patients on maintenance haemodialysis in the Northern Territory, we assessed the relationship between ferritin and transferrin saturation (TSAT) as measures of iron status and ferritin and C-reactive protein (CRP) as markers of inflammation. Methods. We performed a retrospective cohort analysis of data from adult patients (≥18 years) on maintenance haemodialysis (>3 months) from 2004 to 2011. Results. There were 1568 patients. The mean age was 53.9 (11.9) years. 1244 (79.3%) were Indigenous. 44.2% () were male. Indigenous patients were younger (mean age [52.3 (11.1) versus 57.4 (15.2), ]) and had higher CRP [14.7 mg/l (7–35) versus 5.9 mg/l (1.9–17.5), ], higher median serum ferritin [1069 µg/l (668–1522) versus 794.9 µg/l (558.5–1252.0), ], but similar transferrin saturation [26% (19–37) versus 28% (20–38), ]. We observed a small positive correlation between ferritin and TSAT (, ), no correlation between ferritin and CRP ( = 0.001, ), and positive association between high serum ferritin and TSAT (), Indigenous ethnicity (), urea reduction ratio (), and gender () after adjustment in mixed regression analysis. Conclusion. Serum ferritin and TSAT may inadequately reflect iron status in this population. The high ferritin was poorly explained by inflammation

    Serum vitamin D levels, diabetes and cardio-metabolic risk factors in Aboriginal and Torres Strait Islander Australians

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    Assesses levels of serum 25(OH)D in Aboriginal and Torres Strait Islander Australians and explores relationships between 25(OH)D and cardio-metabolic risk factors and diabetes. Abstract Background: Low levels of serum 25 – hydroxy vitamin D (25(OH)D), have been associated with development of type 2 diabetes and cardiovascular disease (CVD); however there are limited data on serum 25(OH)D in Indigenous Australians, a population at high risk for both diabetes and CVD. We aimed to assess levels of serum 25(OH)D in Aboriginal and Torres Strait Islander Australians and to explore relationships between 25(OH)D and cardio-metabolic risk factors and diabetes. Methods: 592 Aboriginal and/or Torres Strait Islander Australian participants of The eGFR (estimated glomerular filtration rate) Study, a cross-sectional analysis of a cohort study performed in 2007 – 2011, from urban and remote centres within communities, primary care and tertiary hospitals across Northern Territory, Far North Queensland and Western Australia. Assessment of serum 25(OH)D, cardio-metabolic risk factors (central obesity, diabetes, hypertension, history of cardiovascular disease, current smoker, low HDL-cholesterol), and diabetes (by history or HbA1c ≥ 6.5%) was performed. Associations were explored between 25(OH)D and outcome measures of diabetes and number of cardio-metabolic risk factors. Results: The median (IQR) serum 25(OH)D was 60 (45 – 77) nmol/L, 31% had 25(OH)D <50 nmol/L. For participants with 25(OH)D < 50 vs ≥ 50 nmol/L, cardio-metabolic risk profile differed for: diabetes (54%, 36% p < 0.001), past history of cardiovascular disease (16%, 9%, p = 0.014), waist-hip ratio (0.98, 0.92, p < 0.001), urine albumin-creatinine ratio (2.7, 1.5 mg/mmol, p < 0.001). The OR (95% CI) for diabetes was 2.02 (1.03 – 3.95) for people in the lowest vs highest tertiles of 25(OH)D (<53 vs >72 nmol/L, respectively) after adjusting for known cardio-metabolic risk factors. Conclusion: The percentage of 25(OH)D levels <50 nmol/L was high among Aboriginal and Torres Strait Islander Australians from Northern and Central Australia. Low 25(OH)D level was associated with adverse cardio-metabolic risk profile and was independently associated with diabetes. These findings require exploration in longitudinal studies
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