Complex Structure of Dynamic Stall on Wind Turbine Airfoils

Fluid dynamics video demonstrating the evolution of dynamic stall on a wind turbine blade.Comment: 2 pages with 2 attached movie

Stratégies de réalisation de guides polymères pour la modulation électro-optique à haut débit

National audienceDe nouveaux polymères électro-optiques, sont mis en œuvre pour réaliser des guides selon deux types d'ingénierie de matériaux. L'une consiste à utiliser un polymère non-linéaire greffé et réticulable et l'autre utilise un matériau hôte, ayant une température de transition vitreuse élevée. Nous présentons ici, les difficultés rencontrées lors de la réalisation des guides et les stratégies développées pour aboutir, avec ces nouveaux matériaux, à des guides optiques monomodes

Toward digital twins for sawmill production planning and control : benefits, opportunities and challenges

Sawmills are key elements of the forest product industry supply chain, and they play important economic, social, and environmental roles. Sawmill production planning and control are, however, challenging owing to severalfactors, including, but not limited to, the heterogeneity of the raw material. The emerging concept of digital twins introduced in the context of Industry 4.0 has generated high interest and has been studied in a variety of domains, including production planning and control. In this paper, we investigate the benefits digital twins would bring to the sawmill industry via a literature review on the wider subject of sawmill production planning and control. Opportunities facilitating their implementation, as well as ongoing challenges from both academic and industrial perspectives, are also studied

Analyse des pertes optiques dans les guides polymères

National audienceLes guides polymères peuvent présenter des pertes optiques très différentes suivant les matériaux mis en jeux et les technologies utilisées. Il est donc important de pouvoir distinguer entre ce qui est inhérent strictement au matériau, les pertes intrinsèques, et, ce qui relève de la technologie de fabrication des guides, les pertes extrinsèques, afin d'optimiser au mieux la propagation dans ces circuits optiques. A l'aide de différentes techniques de mesure développées au laboratoire, nous essayons dans cet article de cerner les pertes limites de ces matériaux en nous appuyant aussi, sur des mesures expérimentales de guides dont nous maitrisons la technologie de mise en œuvre

A randomised controlled trial and cost-effectiveness evaluation of 'booster' interventions to sustain increases in physical activity in middle-aged adults in deprived urban neighbourhoods

Background: More evidence is needed on the potential role of 'booster' interventions in the maintenance of increases in physical activity levels after a brief intervention in relatively sedentary populations. Objectives: To determine whether objectively measured physical activity, 6 months after a brief intervention, is increased in those receiving physical activity 'booster' consultations delivered in a motivational interviewing (MI) style, either face to face or by telephone. Design: Three-arm, parallel-group, pragmatic, superiority randomised controlled trial with nested qualitative research fidelity and geographical information systems and health economic substudies. Treatment allocation was carried out using a web-based simple randomisation procedure with equal allocation probabilities. Principal investigators and study statisticians were blinded to treatment allocation until after the final analysis only. Setting: Deprived areas of Sheffield, UK. Participants: Previously sedentary people, aged 40-64 years, living in deprived areas of Sheffield, UK, who had increased their physical activity levels after receiving a brief intervention. Interventions: Participants were randomised to the control group (no further intervention) or to two sessions of MI, either face to face ('full booster') or by telephone ('mini booster'). Sessions were delivered 1 and 2 months post-randomisation. Main outcome measures: The primary outcome was total energy expenditure (TEE) per day in kcal from 7-day accelerometry, measured using an Actiheart device (CamNtech Ltd, Cambridge, UK). Independent evaluation of practitioner competence was carried out using the Motivational Interviewing Treatment Integrity assessment. An estimate of the per-participant intervention costs, resource use data collected by questionnaire and health-related quality of life data were analysed to produce a range of economic models from a short-term NHS perspective. An additional series of models were developed that used TEE values to estimate the long-term cost-effectiveness. Results: In total, 282 people were randomised (control = 96; mini booster = 92, full booster = 94) of whom 160 had a minimum of 4 out of 7 days' accelerometry data at 3 months (control = 61, mini booster = 47, full booster = 52). The mean difference in TEE per day between baseline and 3 months favoured the control arm over the combined booster arm but this was not statistically significant (-39 kcal, 95% confidence interval -173 to 95, p = 0.57). The autonomy-enabled MI communication style was generally acceptable, although some participants wanted a more paternalistic approach and most expressed enthusiasm for monitoring and feedback components of the intervention and research. Full boosters were more popular than mini boosters. Practitioners achieved and maintained a consistent level of MI competence. Walking distance to the nearest municipal green space or leisure facilities was not associated with physical activity levels. Two alternative modelling approaches both suggested that neither intervention was likely to be cost-effective. Conclusions: Although some individuals do find a community-based, brief MI 'booster' intervention supportive, the low levels of recruitment and retention and the lack of impact on objectively measured physical activity levels in those with adequate outcome data suggest that it is unlikely to represent a clinically effective or cost-effective intervention for the maintenance of recently acquired physical activity increases in deprived middle-aged urban populations. Future research with middle-aged and relatively deprived populations should explore interventions to promote physical activity that require less proactive engagement from individuals, including environmental interventions

Research and practice priorities in pilonidal sinus disease: a consensus from the PITSTOP study

Aim: Pilonidal sinus disease is a common condition treated by colorectal surgeons. There is a lack of literature in the field to guide optimal management of this condition. As part of the PITSTOP study, we aimed to identify policy and research priorities to provide direction to the field. Method: Patients and surgeons were invited to participate. A ‘So what, now what’ exercise was conducted, informed by data from PITSTOP. This generated statements for research and practice priorities. A three‐round online Delphi study was conducted, ranking statements based on policy and research separately. Statements were rated 1 (not important) to 9 (important). Statements that were rated 7–9 by more than 70% of participants were entered into the consensus meeting. Personalized voting feedback was shown between rounds. A face‐to‐face meeting was held to discuss statements, and participants were asked to rank statements using a weighted choice vote. Results: Twenty‐two people participated in the focus group, generating 14 research and 19 policy statements. Statements were voted on by 56 participants in round 1, 53 in round 2 and 51 in round 3. A total of 15 policy statements and 19 research statements were discussed in the consensus round. Key policy statements addressed treatment strategies and intensity, surgeon training opportunities, need for classification and the impact of treatment on return to work. Research recommendations included design of future trials, methodology considerations and research questions. Conclusion: This study has identified research and policy priorities in pilonidal sinus disease which are relevant to patients and clinicians. These should inform practice and future research

Classification and stratification in pilonidal sinus disease: findings from the PITSTOP cohort

Aim: Research in pilonidal disease faces several challenges, one of which is consistent and useful disease classification. The International Pilonidal Society (IPS) proposed a four‐part classification in 2017. The aim of this work was to assess the validity and reliability of this tool using data from the PITSTOP cohort study. Method: Face validity was assessed by mapping the items/domains in the IPS tool against tools identified through a systematic review. Key concepts were defined as those appearing in more than two‐thirds of published tools. Concurrent and predictive validity were assessed by comparing key patient‐reported outcome measures between groups at baseline and at clinic visit. The outcomes of interest were health utility, Cardiff Wound Impact Questionnaire (CWIQ) and pain score between groups. Significance was set at p = 0.05 a priori. Interrater reliability was assessed using images captured during the PITSTOP cohort. Ninety images were assessed by six raters (two experts, two general surgeons and two trainees), and classified into IPS type. Interrater reliability was assessed using the unweighted kappa and unweighted Gwet's AC1 statistics. Results: For face validity items represented in the IPS were common to other classification systems. Concurrent and predictive validity assessment showed differences in health utility and pain between groups at baseline, and for some treatment groups at follow‐up. Assessors agreed the same classification in 38% of participants [chance‐corrected kappa 0.52 (95% CI 0.42–0.61), Gwet's AC1 0.63 (95% CI 0.56–0.69)]. Conclusion: The IPS classification demonstrates key aspects of reliability and validity that would support its implementation

Wolbachia and DNA barcoding insects: patterns, potential and problems

Wolbachia is a genus of bacterial endosymbionts that impacts the breeding systems of their hosts. Wolbachia can confuse the patterns of mitochondrial variation, including DNA barcodes, because it influences the pathways through which mitochondria are inherited. We examined the extent to which these endosymbionts are detected in routine DNA barcoding, assessed their impact upon the insect sequence divergence and identification accuracy, and considered the variation present in Wolbachia COI. Using both standard PCR assays (Wolbachia surface coding protein – wsp), and bacterial COI fragments we found evidence of Wolbachia in insect total genomic extracts created for DNA barcoding library construction. When >2 million insect COI trace files were examined on the Barcode of Life Datasystem (BOLD) Wolbachia COI was present in 0.16% of the cases. It is possible to generate Wolbachia COI using standard insect primers; however, that amplicon was never confused with the COI of the host. Wolbachia alleles recovered were predominantly Supergroup A and were broadly distributed geographically and phylogenetically. We conclude that the presence of the Wolbachia DNA in total genomic extracts made from insects is unlikely to compromise the accuracy of the DNA barcode library; in fact, the ability to query this DNA library (the database and the extracts) for endosymbionts is one of the ancillary benefits of such a large scale endeavor – for which we provide several examples. It is our conclusion that regular assays for Wolbachia presence and type can, and should, be adopted by large scale insect barcoding initiatives. While COI is one of the five multi-locus sequence typing (MLST) genes used for categorizing Wolbachia, there is limited overlap with the eukaryotic DNA barcode region

Built Environment Ecosystems Framework towards Sustainable Urban Housing Infrastructure

As the rates of urbanization increase to unprecedented levels, the urgent need for sustainable housing and infrastructure has become a widespread global challenge with social, economic and ecological implications. The housing sector directly impacts the majority of the United Nations (UN) Sustainable Development Goals (SGDs). However, striving to achieve these goals in a compartmentalized or siloed manner has impeded the implementation of transformational solutions that increase the security and wellbeing of urban populations. Here, we introduce the Built Environment Ecosystems (BEE) framework, alongside a case study from the Ecological Living Module (ELM) UNEP Program, through an integrated systems approach with synergistic impact. We demonstrate how the multifunctional interlinking of building systems that harness local bioclimatic resources (ie. solar, wind, water, food, agricultural waste, biomaterials) can more viably address a broad spectrum of sustainable development challenges, while increasing local stakeholder agency. We outline how the BEE framework enables the association of SDGs as an integrated package, with an ELM performing as a scalable but selfreliant Ecosystem of Systems, that could enable systemic change, suggesting the need for further research towards a scale up in the density of such housing systems across multiple climatic and cultural contexts towards ubiquitous sustainable urban housing

Chronic Intestinal Failure in Children : An International Multicenter Cross-Sectional Survey

Background: The European Society for Clinical Nutrition and Metabolism database for chronic intestinal failure (CIF) was analyzed to investigate factors associated with nutritional status and the intravenous supplementation (IVS) dependency in children. Methods: Data collected: demographics, CIF mechanism, home parenteral nutrition program, z-scores of weight-for-age (WFA), length or height-for-age (LFA/HFA), and body mass index-for-age (BMI-FA). IVS dependency was calculated as the ratio of daily total IVS energy over estimated resting energy expenditure (%IVSE/REE). Results: Five hundred and fifty-eight patients were included, 57.2% of whom were male. CIF mechanisms at age 1-4 and 14-18 years, respectively: SBS 63.3%, 37.9%; dysmotility or mucosal disease: 36.7%, 62.1%. One-third had WFA and/or LFA/HFA z-scores 125%. Multivariate analysis showed that mechanism of CIF was associated with WFA and/or LFA/HFA z-scores (negatively with mucosal disease) and %IVSE/REE (higher for dysmotility and lower in SBS with colon in continuity), while z-scores were negatively associated with %IVSE/REE. Conclusions: The main mechanism of CIF at young age was short bowel syndrome (SBS), whereas most patients facing adulthood had intestinal dysmotility or mucosal disease. One-third were underweight or stunted and had high IVS dependency. Considering that IVS dependency was associated with both CIF mechanisms and nutritional status, IVS dependency is suggested as a potential marker for CIF severity in children.Peer reviewe