A New Actuator Surface Model with Improved Wake Model for CFD Simulations of Rotorcraft

Simulations of rotorcraft operating in unsteady flow-fields, manoeuvring flight, or with complex rotor configurations pose a significant challenge to current simulation methods. Simplified rotor models lack the generality required for the diverse range of operating conditions that a rotor may be exposed to, while higher-fidelity Navier-Stokes CFD simulations with fully-resolved rotors are expensive in terms of computational resources, simulation time, and pre-processing time. Here we present a new rotor and wake model which is fully-coupled to a CFD solver and is based on the actuator surface model. This model is designed to reduce the cost of complex rotorcraft simulations in comparison with fully-resolved simulations and provide greater generality than other rotor models. Results from simulations using the new actuator surface and wake model provide validation of the concept for hover and forward flight. The spanwise loading distribution, thrust coefficient, and wake geometry are shown to be reasonable in comparison with data from experiments, fully-resolved simulations, and prescribed wake models

Changing patterns of domestic abuse during Covid-19 lockdown

The effects of preventing a COVID-19 health crisis have had unintended consequences on domestic abuse (DA) victimization. We contribute to the literature on domestic abuse in lockdown by providing insight on how changing patterns of domestic abuse can explain differences in magnitudes reported across studies. We examine the patterns of domestic abuse during the COVID-19 lockdown in Greater London and find that the lockdown changed the nature of reporting and the type of relationship the abuse occurs within. While abuse by current partners as well as family members increased on average by 8.1% and 17.1% respectively over the lockdown period, abuse by ex-partners declined by 11.4%. These findings show that reporting the average change in domestic abuse during lockdown can be misleading when designing a policy response. Moreover, we show that all the increase in domestic abuse calls is driven by third party reporting, particularly evident in areas with high density. This suggests that under reporting is present in the lockdown, particularly in households where the abuse cannot be reported by an outsider. Although these findings pertain to the COVID-19 lockdown, they also highlight the role that victim exposure and proximity has in affecting domestic abuse

Coupling of an unsteady aerodynamics model with a computational fluid dynamics solver

Momentum source methods are an efficient means of representing airfoils in Navier–Stokes computational fluid dynamics (CFD) simulations. Momentum source terms are added to the Navier–Stokes equations instead of resolving the solid boundary of the airfoil with a mesh. These source terms are calculated using an aerodynamics model. This approach is useful where the overall performance and mid- to far-field influence of a wing or rotor are desired and details of the flowfield near the blade are not the objective of the simulation. One example is simulation of rotorcraft operations where the objective may be to assess an operation’s feasibility in terms of control margins, rather than to inform rotor design decisions. Coupling an aerodynamics model to a CFD solver is straightforward in cases where the airflow relative to the blade is steady. Unsteady conditions require an unsteady aerodynamics model, complicating the coupling with the CFD solver. A coupling method is proposed whereby the incident velocity is extracted from the CFD solution and corrected using a theory-based approximation for the unsteady induced velocity. The steady-state momentum source method is demonstrated for two- and three-dimensional simulations, and the unsteady coupling method is validated against experiments on a pitching airfoil and verified for blade–vortex interactions. The unsteady coupling method enables meaningful incident velocities to be extracted from unsteady flowfields, as shown by agreement with experiments and simulations using analytical expressions for the incident velocity in place of the CFD solver

Reducing postharvest losses in the OIC member countries

It is universally understood that postharvest losses are high, particularly in less developed economies, and that this is an issue of keen interest to researchers, practitioners and policy makers alike. Postharvest losses are defined by COMCEC as food damage or degradation of food during different stages of the food supply chain that are incurred between the farm-gate and prior to retail and consumption. Highlights of this report. • Clear evidence of substantial postharvest losses across all Members and commodity groups and these are similar to those reported in non-OIC Member Countries. Figures are estimates though. • Pockets of high physical losses identified: e.g., fruit and vegetables, root and tuber crops and meat and meat products • High economic losses for cereals and fish and fish products • Nutrition losses were rarely reported but for cereals in Sub-Saharan Africa losses could be equivalent to the annual caloric requirement of 48 million people • Weak policy support to effecting loss reduction strategies almost universal • Limited on-going measurement of postharvest losses means impact of innovation and policy was hard to measure This analysis of postharvest losses in the OIC Member Countries, conducted by a team from the Natural Resources Institute (NRI), University of Greenwich between January and July 2016, sought to provide ways to contribute to reduced postharvest losses. The analysis sought to identify approach and practices, and policy recommendation for future investments. The methods used were a combination of a brief literature review, an on-line survey of key informants, and a series of commodity specific case studies that included three field visits. The scope of the study included all OIC Member Countries, all three official Regional Groups of OIC Member Countries (African, Asian and Arab), and representation from seven commodity groups (cereals, roots and tubers, oilseeds and pulses, fruit and vegetables, meat and meat products, milk and dairy products and fish and seafood). Field visits were conducted in Indonesia, Bangladesh and Oman. A conceptual framework was developed from knowledge of the literature and the challenges and complexities of measuring postharvest losses. The postharvest physical losses in OIC countries reported by commodity group for the literature review, online survey and case/field studies suggested that they were not that different from the global losses for each commodity that the authors extracted from FAO data. For cereals, root and tuber crops, oilseeds and pulses, fruit and vegetables, meat and meat products, milk and dairy products and fish and fish products, the extrapolated losses from FAO data was 12-15%, 22-34%, 15-38%, 11-12% and 16-25% respectively. Compared to this, the range found from the OIC study was 9-48%, 7-50%, 14%, 3-65%. 6-40%, 2-30% and 3-50% respectively. Although the spread is wider that the estimates from FAO reports, it is considered to be consistent. Thus the postharvest losses in OIC countries are not that different from elsewhere. Some commodities and countries are well covered (e.g. maize in Uganda), but most are poorly analysed in existing research, with some significant knowledge gaps identified (e.g., some countries with little or no literature, other commodities under researched). The postharvest economic losses were less consistently reported and difficult to compare with the global situation due to differences in reporting (monetary amounts or percentages), different sizes of economies and differing product values. For example, postharvest losses were considered large and the order of US$1 to 4 billion and US$4.8 billion per annum for cereals (Egypt and Uganda) and fish (Indonesia) respectively but as low as US$8 to 21 million per annum for tomatoes in Bangladesh. This probably reflects the difficulties in estimating losses as well as valuation. The least known/understood postharvest loss in our analysis was regarding the quality/nutrition losses and was limited to calories in cereals to vitamin A for biofortified cassava. Such information will be critical for countries suffering from nutrition deficiency. Bringing together the estimates for physical, economic and quality/nutrition losses in the OIC Member Countries along with comparisons with the global situation has highlighted a few lessons and gaps. The bulk of the information obtained from the literature review, online survey and case/desk studies concerned the physical losses. This is probably because physical losses are easier to estimate either by direct measurement or by visual inspection. It should be noted however, that all are estimates and few studies are quantitative. Much less was reported concerning the economic losses and the amounts will differ markedly from one value chain for another, even for the same product and commodity. This, therefore, is an area of research that would require more inputs and due to the high cost of undertaking such work, the target value chains would need to be selected according to economic contribution to the OIC Member Country. In all cases the monetary cost of the losses was significant but it was not always known how the costs were estimated. If the monetary losses could be captured, this will lead to benefits for the consumer and actors in the value chain along with potential benefits to national balance of payments. The least known was regarding the quality/nutrition losses but such information may be critical for countries suffering from nutrition deficiency, particularly calories and vitamins. Key findings concerning specific postharvest research issues was sparse and geographically scattered. Some commodities have a greater coverage than others (e.g. artisanal fisheries and maize are far more researched that cattle or bananas). Some OIC Member Countries and regions have seen much more postharvest loss research and practice than others. For example, the Africa Group and low income countries has seen more support, probably from donors, which has been driving postharvest loss research. Commodity specific findings are reported and these relate to the product characteristics, uses and markets they each fall into. For example for the cereals, the challenges were related mainly to drying and storage, especially related to pests in store, whereas for other root crops peeling, storage and marketing were the highest postharvest loss elements reported. For oilseed and pulses, key issues related to storage largely due to the impact of storage pests. For fruit and vegetables, the issue was the high perishability and ease of damage. Meat and meat products issues related to high transport losses for live animals are often a factor of distance to market or slaughter and the absence of infrastructure including adequate cold chains. For milk and dairy products, key issues were related to the need to upgrade the milk and dairy value chains, particularly setting standards, organising farmers and supporting the emergence of cool-chains. Lastly for fish and fish products, the key issues related to postharvest losses in aquaculture. Investments in cold chains and improved postharvest handling could substantially reduce postharvest losses and food safety concerns. A range of common challenges were identified. These include the underestimation of the impact of rodents on losses, the importance of the impact of actions taken on farm that can affect postharvest losses, the impact of toxins such as aflatoxin, the benefit from development of cold-chain infrastructure and the existence of policies supporting strategic crops has, in some cases, led to a history of under-investment in postharvest management by the private sector. The impact of gender also appears to have under investigated or reported. A range of common solutions were identified on the farm, in the postharvest value chain and ones that were systemic such as rules and standards, capacity and training etc. For example breeding to improve the storability of fruit and vegetables and root and tuber crops would reduce losses, early quality differentiation to improve marketability etc. A number of examples of best practice were given related to ownership, the value of ICT technology, investment for stored fruit and vegetables and sharing information via mobile phones, strategic investment such as cold chain infrastructure, the emergence of new industries from waste, multi-actor collaboration and the importance of national loss-reporting systems (for example APHLIS and Indonesian Fisheries Sector). A number of policy recommendations were suggested to advise OIC Member Countries locate and quantify postharvest losses. These focused on the need for establishing national postharvest loss reduction coordination approaches, establishing consistent methods, sharing best practice and promoting system wide efforts, promoting capacity building and sharing among OIC Member Countries, facilitating local, national and, potentially, regional multi-stakeholder commodity platforms etc. Lastly, to overcome the challenge that postharvest losses is generally more complex than pre-harvest losses due to the greater diversity of products and end uses and markets that the products are directed at a strategy for prioritise which commodity groups and value chains are most important at the national level was suggested

Understanding the formation and influence of attitudes in patients' treatment choices for lower back pain: Testing the benefits of a hybrid choice model approach

A growing number of studies across different fields are making use of a new class of choice models, labelled variably as hybrid model structures or integrated choice and latent variable models, and incorporating the role of attitudes in decision making. To date, this technique has not been used in health economics. The present paper looks at the formation of such attitudes and their role in patients' treatment choices in the context of low back pain. We use stated choice data collected from a sample of 561 patients with 348 respondents referred to a regional spine centre in Middelfart, Denmark in spring/summer 2012. We show how the hybrid model structure is able to make a link between attitudinal questions and treatment choices, and also explains variation of these attitudes across key socio-demographic groups. However, we also show how, in this case, only a small share of the overall heterogeneity is linked to the latent attitude construct. Despite their growing popularity, the key findings of the advanced model, despite a greater insight into the drivers of attitudes and small gains in efficiency, are no different from standard approaches which remain easier to apply

Domestication of Campylobacter jejuni NCTC 11168

Reference and type strains of well-known bacteria have been a cornerstone of microbiology research for decades. The sharing of well-characterized isolates among laboratories has run in parallel with research efforts and enhanced the reproducibility of experiments, leading to a wealth of knowledge about trait variation in different species and the underlying genetics. Campylobacter jejuni strain NCTC 11168, deposited at the National Collection of Type Cultures in 1977, has been adopted widely as a reference strain by researchers worldwide and was the first Campylobacter for which the complete genome was published (in 2000). In this study, we collected 23 C . jejuni NCTC 11168 reference isolates from laboratories across the UK and compared variation in simple laboratory phenotypes with genetic variation in sequenced genomes. Putatively identical isolates, identified previously to have aberrant phenotypes, varied by up to 281 SNPs (in 15 genes) compared to the most recent reference strain. Isolates also display considerable phenotype variation in motility, morphology, growth at 37 °C, invasion of chicken and human cell lines, and susceptibility to ampicillin. This study provides evidence of ongoing evolutionary change among C. jejuni isolates as they are cultured in different laboratories and highlights the need for careful consideration of genetic variation within laboratory reference strains. This article contains data hosted by Microreact

Incorporating the social dimension into hydrogeochemical investigations for rural development: the Bir Al-Nas approach for socio-hydrogeology

A replicable multidisciplinary approach is presented for science-based groundwater management practices: Bir Al-Nas (Bottom-up IntegRated Approach for sustainabLe grouNdwater mAnagement in rural areaS). This approach provides a practical example of the concept of “socio-hydrogeology”, a way of incorporating the social dimension into hydrogeological investigations, as reinforced by the translation of the Arabic bir al-nas: “the people’s well”. To achieve this, hydrogeologists act as “social hydrologists” during their monitoring activities, which often bring them into contact with local communities and end users (and polluters) of water. Not only can they retrieve reliable information about traditional know-how and local issues, but they can also change the public perception of science/scientists to create the basis for mutual collaboration and understanding in view of implementing improved integrated groundwater management. The final outcomes are expected to be an increased awareness of communities at the local level and a clear understanding of their water issues and needs from the very early stages of the investigation. Although the importance of using such methods in groundwater analysis and management is widely recognized, hydrogeological investigations are currently dominated by sectorial approaches that are easier to implement but less sustainable. The pressure of population growth, the shift towards more water-dependent economies, climate change and its impact on water availability will require scientists to use a more integrated approach, such as Bir Al-Nas, when dealing with increasing water pollution and water-scarcity issues.A replicable multidisciplinary approach is presented for science-based groundwater management practices: Bir Al-Nas (Bottom-up IntegRated Approach for sustainabLe grouNdwater mAnagement in rural areaS). This approach provides a practical example of the concept of "socio-hydrogeology", a way of incorporating the social dimension into hydrogeological investigations, as reinforced by the translation of the Arabic bir al-nas: "the people's well". To achieve this, hydrogeologists act as "social hydrologists" during their monitoring activities, which often bring them into contact with local communities and end users (and polluters) of water. Not only can they retrieve reliable information about traditional know-how and local issues, but they can also change the public perception of science/scientists to create the basis for mutual collaboration and understanding in view of implementing improved integrated groundwater management. The final outcomes are expected to be an increased awareness of communities at the local level and a clear understanding of their water issues and needs from the very early stages of the investigation. Although the importance of using such methods in groundwater analysis and management is widely recognized, hydrogeological investigations are currently dominated by sectorial approaches that are easier to implement but less sustainable. The pressure of population growth, the shift towards more water-dependent economies, climate change and its impact on water availability will require scientists to use a more integrated approach, such as Bir Al-Nas, when dealing with increasing water pollution and water-scarcity issues

EurOP2E – the European Open Platform for Prescribing Education, a consensus study among clinical pharmacology and therapeutics teachers

Purpose Sharing and developing digital educational resources and open educational resources has been proposed as a way to harmonize and improve clinical pharmacology and therapeutics (CPT) education in European medical schools. Previous research, however, has shown that there are barriers to the adoption and implementation of open educational resources. The aim of this study was to determine perceived opportunities and barriers to the use and creation of open educational resources among European CPT teachers and possible solutions for these barriers. Methods CPT teachers of British and EU medical schools completed an online survey. Opportunities and challenges were identified by thematic analyses and subsequently discussed in an international consensus meeting. Results Data from 99 CPT teachers from 95 medical schools were analysed. Thirty teachers (30.3%) shared or collaboratively produced digital educational resources. All teachers foresaw opportunities in the more active use of open educational resources, including improving the quality of their teaching. The challenges reported were language barriers, local differences, lack of time, technological issues, difficulties with quality management, and copyright restrictions. Practical solutions for these challenges were discussed and include a peer review system, clear indexing, and use of copyright licenses that permit adaptation of resources. Conclusion Key challenges to making greater use of CPT open educational resources are a limited applicability of such resources due to language and local differences and quality concerns. These challenges may be resolved by relatively simple measures, such as allowing adaptation and translation of resources and a peer review system

Harmonizing and improving European education in prescribing: An overview of digital educational resources used in clinical pharmacology and therapeutics

Aim: Improvement and harmonization of European clinical pharmacology and therapeutics (CPT) education is urgently required. Because digital educational resources can be easily shared, adapted to local situations and re-used widely across a variety of educational systems, they may be ideally suited for this purpose. Methods: With a cross-sectional survey among principal CPT teachers in 279 out of 304 European medical schools, an overview and classification of digital resources was compiled. Results: Teachers from 95 (34%) medical schools in 26 of 28 EU countries responded, 66 (70%) of whom used digital educational resources in their CPT curriculum. A total of 89 of such resources were described in detail, including e-learning (24%), simulators to teach pharmacokinetics and/or pharmacodynamics (10%), virtual patients (8%), and serious games (5%). Together, these resources covered 235 knowledge-based learning objectives, 88 skills, and 13 attitudes. Only one third (27) of the resources were in-part or totally free and only two were licensed open educational resources (free to use, distribute and adapt). A narrative overview of the largest, free and most novel resources is given. Conclusion: Digital educational resources, ranging from e-learning to virtual patients and games, are widely used for CPT education in EU medical schools. Learning objectives are based largely on knowledge rather than skills or attitudes. This may be improved by including more real-life clinical case scenarios. Moreover, the majority of resources are neither free nor open. Therefore, with a view to harmonizing international CPT education, more needs to be learned about why CPT teachers are not currently sharing their educational materials