1,640 research outputs found

    Manganese pigmented anodized copper as solar selective absorber

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    The study concerns the optical and structural properties of layers obtained by a new efficient surface treatment totally free of chromium species. The process is made up of an anodic oxidation of copper in an alkaline solution followed by an alkaline potassium permanganate dipping post-treatment. Coatings, obtained at the lab and pilot scales, are stable up to 220 °C in air and vacuum, present low emissivity (0.14 at 70 °C) and high solar absorptivity (0.96), i.e. a suitable thermal efficiency (0.84 at 70 °C)

    Disruption of the basal body protein POC1B results in autosomal-recessive cone-rod dystrophy

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    Exome sequencing revealed a homozygous missense mutation (c.317C>G [p.Arg106Pro]) in POC1B, encoding POC1 centriolar protein B, in three siblings with autosomal-recessive cone dystrophy or cone-rod dystrophy and compound-heterozygous POC1B mutations (c.199_201del [p.G1n67del] and c.810+1G>T) in an unrelated person with cone-rod dystrophy. Upon overexpression of POC1B in human TERT-immortalized retinal pigment epithelium 1 cells, the encoded wild-type protein localized to the basal body of the primary cilium, whereas this localization was lost for p.Arg106Pro and p.G1n67del variant forms of POC1B. Morpholino-oligonucleotide-induced knockdown of poc1b translation in zebrafish resulted in a dose-dependent small-eye phenotype, impaired optokinetic responses, and decreased length of photoreceptor outer segments. These ocular phenotypes could partially be rescued by wild-type human POC1B mRNA, but not by c.199_201del and c.317C>G mutant human POC1B mRNAs. Yeast two-hybrid screening of a human retinal cDNA library revealed FAM161A as a binary interaction partner of POC1B. This was confirmed in coimmunoprecipitation and colocalization assays, which both showed loss of FAM161A interaction with p.Arg106Pro and p.G1n67del variant forms of POC1B. FAM161A was previously implicated in autosomal-recessive retinitis pigmentosa and shown to be located at the base of the photoreceptor connecting cilium, where it interacts with several other ciliopathy-associated proteins. Altogether, this study demonstrates that POC1B mutations result in a defect of the photoreceptor sensory cilium and thus affect cone and rod photoreceptors

    Clinical characterization of 66 patients with congenital retinal disease due to the deep-intronic c.2991+1655A>G mutation in CEP290

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    Purpose: To describe the phenotypic spectrum of retinal disease caused by the c.2991+1655A>G mutation in CEP290 and to compare disease severity between homozygous and compound heterozygous patients. Methods: Medical records were reviewed for best-corrected visual acuity (BCVA), age of onset, fundoscopy descriptions. Foveal outer nuclear layer (ONL) and ellipsoid zone (EZ) presence was assessed using spectral-domain optical coherence tomography (SD-OCT). Differences between compound heterozygous and homozygous patients were analyzed based on visual performance and visual development. Results: A total of 66 patients were included. The majority of patients had either light perception or no light perception. In the remaining group of 14 patients, median BCVA was 20/195 Snellen (0.99 LogMAR; range 0.12-1.90) for the right eye, and 20/148 Snellen (0.87 LogMAR; range 0.22-1.90) for the left. Homozygous patients tended to be more likely to develop light perception compared to more severely affected compound heterozygous patients (P = 0.080) and are more likely to improve from no light perception to light perception (P = 0.022) before the age of 6 years. OCT data were available in 12 patients, 11 of whom had retained foveal ONL and EZ integrity up to 48 years (median 23 years) of age. Conclusions: Homozygous patients seem less severely affected compared to their compound-heterozygous peers. Improvement of visual function may occur in the early years of life, suggesting a time window for therapeutic intervention up to the approximate age of 17 years. This period may be extended by an intact foveal ONL and EZ on OCT

    Living with ‘melanoma’…for a day: a phenomenological analysis of medical students’ simulated experiences

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    Background Despite the rising incidence of melanoma, medical students have progressively fewer opportunities to encounter patients with this important condition. Curricula tend to attach the greatest value to intellectual forms of learning. Compared to intellectual learning, however, experiential learning affords students deep insights about a condition. Doctors who experience ill health are more empathic towards patients. However opportunities to learn about cancer experientially are limited. Temporary transfer tattoos can simulate the ill health associated with melanoma. We reasoned that, if doctors who have been sick are more empathic, temporarily ‘having’ melanoma might have a similar effect. Objectives Explore the impact of wearing a melanoma tattoo on medical students’ understanding of patienthood and attitudes towards patients with melanoma. Methods Ten fourth year medical students were recruited to a simulation. They wore a melanoma tattoo for 24 hours and listened to a patient’s account of receiving their diagnosis. Data were captured using audio-diaries and face-to-face interviews, transcribed, and analysed phenomenologically using the template analysis method. Results There were four themes: 1) Melanoma simulation: opening up new experiences; 2) Drawing upon past experiences; 3) A transformative introduction to patienthood; 4) Doctors in the making: seeing cancer patients in a new light. Conclusions By means of a novel simulation, medical students were introduced to lived experiences of having a melanoma. Such an inexpensive simulation can prompt students to reflect critically on the empathetic care of such patients in the future

    Sugarcoated isolation: Evidence that social avoidance is linked to higher basal glucose levels and higher consumption of glucose

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    Objective: The human brain adjusts its level of effort in coping with various life stressors as a partial function of perceived access to social resources. We examined whether people who avoid social ties maintain a higher fasting basal level of glucose in their bloodstream, reflecting a strategy to draw more on personal resources when threatened.Methods: For Study 1, we obtained fasting blood glucose and adult attachment orientations data from 60 undergraduate women at the University of Virginia. For Study 2, we collected measures of fasting blood glucose, self-reported trait anxiety, DHEA-cortisol, hypertension, and adult attachment orientations from 285 older adults of mixed gender, using a measure of attachment style different from study 1.Results: In study 1, fasting blood glucose levels corresponded with higher attachment avoidance scores after statistically adjusting for interpersonal anxiety. For study 2, fasting blood glucose continued to correspond with higher adult attachment avoidance even after statistically adjusting for interpersonal anxiety, trait anxiety, DHEA-cortisol and hypertension. Conclusions: Results suggest socially avoidant individuals upwardly adjust their basal glucose levels with the expectation of increased personal effort because of limited access to social resources

    Orientation toward humans predicts cognitive performance in orang-utans

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    The authors acknowledge the Swiss National Science Foundation and following foundations who have financially supported this project: A. H. Schultz Foundation, Paul Schiller Foundation and the Claraz Foundation in Switzerland and Waldemar von Frenckells Foundation, Ella and Georgh Ehrnrooths Foundation, Otto A. Malms Donationsfond, Nordenskiöld Samfundet and Oskar Öflunds Foundation in Finland.Non-human animals sometimes show marked intraspecific variation in their cognitive abilities that may reflect variation in external inputs and experience during the developmental period. We examined variation in exploration and cognitive performance on a problem-solving task in a large sample of captive orang-utans (Pongo abelii & P. pygmaeus, N = 103) that had experienced different rearing and housing conditions during ontogeny, including human exposure. In addition to measuring exploration and cognitive performance, we also conducted a set of assays of the subjects’ psychological orientation, including reactions towards an unfamiliar human, summarized in the human orientation index (HOI), and towards novel food and objects. Using generalized linear mixed models we found that the HOI, rather than rearing background, best predicted both exploration and problem-solving success. Our results suggest a cascade of processes: human orientation was accompanied by a change in motivation towards problem-solving, expressed in reduced neophobia and increased exploration variety, which led to greater experience, and thus eventually to higher performance in the task. We propose that different experiences with humans caused individuals to vary in curiosity and understanding of the physical problem-solving task. We discuss the implications of these findings for comparative studies of cognitive ability.Publisher PDFPeer reviewe

    Current status and future prospects of epidemiology and public health training and research in the WHO African region

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    Since 1991, there has been increasing epidemiological research productivity in WHO/AFRO that is associated with the number of epidemiology programmes and burden of HIV/AIDS cases. More capacity building and training initiatives in epidemiology are required to promote research and address the public health challenges facing the continent

    How can we get close to zero? The potential contribution of biomedical prevention and the investment framework towards an effective response to HIV.

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    BACKGROUND: In 2011 an Investment Framework was proposed that described how the scale-up of key HIV interventions could dramatically reduce new HIV infections and deaths in low and middle income countries by 2015. This framework included ambitious coverage goals for prevention and treatment services resulting in a reduction of new HIV infections by more than half. However, it also estimated a leveling in the number of new infections at about 1 million annually after 2015. METHODS: We modeled how the response to AIDS can be further expanded by scaling up antiretroviral treatment (ART) within the framework provided by the 2013 WHO treatment guidelines. We further explored the potential contributions of new prevention technologies: 'Test and Treat', pre-exposure prophylaxis and an HIV vaccine. FINDINGS: Immediate aggressive scale up of existing approaches including the 2013 WHO guidelines could reduce new infections by 80%. A 'Test and Treat' approach could further reduce new infections. This could be further enhanced by a future highly effective pre-exposure prophylaxis and an HIV vaccine, so that a combination of all four approaches could reduce new infections to as low as 80,000 per year by 2050 and annual AIDS deaths to 260,000. INTERPRETATION: In a set of ambitious scenarios, we find that immediate implementation of the 2013 WHO antiretroviral therapy guidelines could reduce new HIV infections by 80%. Further reductions may be achieved by moving to a 'Test and Treat' approach, and eventually by adding a highly effective pre-exposure prophylaxis and an HIV vaccine, if they become available

    The Moral of the Tale: Stories, Trust, and Public Engagement with Clinical Ethics via Radio and Theatre.

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    Trust is frequently discussed with reference to the professional-patient relationship. However, trust is less explored in relation to the ways in which understanding of, and responses to, questions of ethics are discussed by both the "public" and "experts." Public engagement activity in healthcare ethics may invoke "trust" in analysing a moral question or problem but less frequently conceives of trust as integral to "public engagement" itself. This paper explores the relationship between trust and the ways in which questions of healthcare ethics are identified and negotiated by both "experts" and the public. Drawing on two examples from the author's "public engagement" work-a radio programme for the British Broadcasting Corporation and work with a playwright and theatre-the paper interrogates the ways in which "public engagement" is often characterized. The author argues that the common approach to public engagement in questions of ethics is unhelpfully constrained by a systemic disposition which continues to privilege the professional or expert voice at the expense of meaningful exchange and dialogue. By creating space for novel interactions between the "expert" and the "public," authentic engagement is achieved that enables not only the participants to flourish but also contributes to trust itself
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