549 research outputs found
Empirical Study of Ground Proximity Effects for Small-scale Electroaerodynamic Thrusters
Electroaerodynamic (EAD) propulsion, where thrust is produced by collisions
between electrostatically-accelerated ions and neutral air, is a potentially
transformative method for indoor flight owing to its silent and solid-state
nature. Like rotors, EAD thrusters exhibit changes in performance based on
proximity to surfaces. Unlike rotors, they have no fragile and quickly spinning
parts that have to avoid those surfaces; taking advantage of the efficiency
benefits from proximity effects may be a route towards longer-duration indoor
operation of ion-propelled fliers. This work presents the first empirical study
of ground proximity effects for EAD propulsors, both individually and as
quad-thruster arrays. It focuses on multi-stage ducted centimeter-scale
actuators suitable for use on small robots envisioned for deployment in
human-proximal and indoor environments. Three specific effects (ground,
suckdown, and fountain lift), each occurring with a different magnitude at a
different spacing from the ground plane, are investigated and shown to have
strong dependencies on geometric parameters including thruster-to-thruster
spacing, thruster protrusion from the fuselage, and inclusion of flanges or
strakes. Peak thrust enhancement ranging from 300 to 600% is found for certain
configurations operated in close proximity (0.2 mm) to the ground plane and as
much as a 20% increase is measured even when operated centimeters away
Microbial biopesticides for integrated crop management : an assessment of environmental and regulatory sustainability
Herbivorous insects and mites, plant diseases and weeds are major impediments to the production of food crops and are increasingly difficult to control with conventional chemicals. This paper focuses on microbial control agents with an emphasis on augmentation. There are marked differences in the availability of products in different countries which can be explained in terms of differences in their regulatory systems. Regulatory failure arises from the application of an inappropriate synthetic pesticides model. An understanding of regulatory innovation is necessary to overcome these problems. Two attempts at remedying regulatory failure in the UK and the Netherlands are assessed. Scientific advances can feed directly into the regulatory process and foster regulatory innovation
Vaccination status and needs of asylum-seeking children in Denmark: a retrospective data analysis.
OBJECTIVES: Asylum seekers to Europe may come from war-torn countries where health systems have broken down, and there is evidence that asylum-seeking children have low coverage of childhood vaccinations, as well as uptake of immunisations in host countries. Such gaps in immunisation have important implications for effective national vaccination programmes. How we approach vaccination in children and adults entering Western Europe, where as a group they face barriers to health services and screening, is a growing debate; however, there are limited data on the vaccination status of these hard-to-reach communities, and robust evidence is needed to inform immunisation strategies. The aim of this study was to explore the vaccination status and needs of asylum-seeking children and adolescents in Denmark. STUDY DESIGN: We conducted a retrospective data analysis of anonymised patient records for asylum-seeking children and adolescents extracted from the Danish Red Cross database. METHODS: We retrospectively searched the Danish Red Cross database for children and adolescents (aged 3 months-17 years) with active asylum applications in Denmark as of October 28, 2015. Data were extracted for demographic characteristics, vaccination status and vaccinations needed by asylum-seeking children presenting to Red Cross asylum centres for routine statutory health screening. RESULTS: We explored the vaccination status and needs of 2126 asylum-seeking children and adolescents. About 64% of the study population were male and 36% were female. Eight nationalities were represented, where 33% of the total of children and adolescents were not immunised in accordance with Danish national guidelines, while 7% were considered partly vaccinated, and 60% were considered adequately vaccinated. Afghan (57% not vaccinated/unknown) and Eritrean (54% not vaccinated/unknown) children were the least likely to be vaccinated of all nationalities represented, as were boys (37% not vaccinated/unknown) compared with girls (27% not vaccinated/unknown) and children and adolescents aged between 12 and 17 years (48% not vaccinated/unknown) compared with 6- to 11-year olds (26%) and 0- to 5-year olds (22%). The health screenings resulted in 1328 vaccinations. The most commonly needed vaccines were diphtheria, tetanus, pertussis, polio and Haemophilus influenzae type b, (DTaP/IPV/Hib) which comprised 49% of the vaccines distributed, followed by the pneumococcal vaccine (Prevnar) (28%) and measles, mumps and rubella (MMR) vaccine (23%). CONCLUSIONS: The finding that nearly one-third of asylum-seeking children and adolescents in Denmark were in need of further vaccinations highlights the gaps in immunisation coverage in these populations. These results point to the need to improve access to health services and promote national vaccine programmes targeted at these communities to facilitate vaccination uptake and increase immunisation coverage to reduce the risk of preventable infectious diseases among asylum-seeking children
Drinking behaviour and alcohol-related harm amongst older adults: analysis of existing UK datasets.
Older adults experience age-related physiological changes that increase sensitivity and decrease tolerance to alcohol and there are a number of age-related harms such as falls, social isolation and elder abuse, which are compounded by alcohol misuse. Despite this unique vulnerability and the fact that the number of older adults is increasing, the literature on drinking behaviour and alcohol-related harm in older adults is sparse. This article describes a secondary analysis of UK data to address this knowledge gap
Multimodal freight transportation: sustainability challenges
Due to globalization in trade, the development of multimodal cargo shipments and the related transport needs have created a range of challenges. Interestingly, sustainability of multimodal freight transportation is still subject to minor consideration, on the grounds that economic interests are frequently positioned much higher than social or environmental objectives. This proposed research plan is needed to assess whether and to what extent the multimodal freight system is achieving the results in the sustainability dimensions: economic, social and environmental. Thus, it will carry out a critical appraisal of the multimodal freight transportation sector to provide an up-to-date knowledge on the sustainability challenges and the potential solutions through doctoral research. This paper structured to present a review of existing literature on freight transportation and multimodal freight transport highlighting the sustainability concerns with multimodal freight transport systems. It also highlights the gaps in knowledge with a justification on the need to address these gaps for the system to function optimally. It also covers the methodology that would be applied and the sources of data that would be reviewed to ensure the aim and objectives are clearly addressed. The paper concludes by discussing the significance of the expected findings in the light of sustainability in multimodal freight transport to the academia, policy makers and the freight transportation industry
Factors influencing access to early intervention for families of children with developmental disabilities: A narrative review
Background
Early intervention (EI) can improve a range of outcomes for families of children with developmental disabilities. However, research indicates the level of access does not always match the level of need. To address disparities, it is essential to identify factors influencing access.
Method
We propose a framework where access to EI is conceptualised as a process that includes three main phases. A narrative review examined potential barriers, facilitators and modifiers of access for each phase.
Results
The process of access to EI includes the following: 1) recognition of need, 2) identification or diagnosis and 3) EI provision or receipt. Several factors affecting access to EI for each phase were identified, related to the family, services, the intersection between family and services, and the context.
Conclusion
A broad range of factors appear to influence the process of access to EI for this population. Our framework can be used in future research investigating access. Broad implications for policy, practice and future research to improve access to EI are discussed
Cannabis treatment outcomes among legally coerced and non-coerced adults
<p>Abstract</p> <p>Background</p> <p>Treatment seeking for cannabis dependence in general, and particularly the number of criminal justice referrals to cannabis treatment, has increased over the past decade. This study aims to compare the characteristics, psychosocial functioning and treatment outcome of those legally coerced into cannabis treatment compared to those entering treatment without legal coercion.</p> <p>Methods</p> <p>This study is a retrospective audit of the administrative clinical records of 27,198 adults presenting to public Texas treatment programs with cannabis as their primary drug problem between 2000 and 2005.</p> <p>Results</p> <p>Of the 69% legally coerced into treatment, there was less psychological distress and greater likelihood of having completed treatment compared with non-coerced clients. Participants who were legally coerced into treatment were also more likely to have received less intensive forms of treatment and to have not used cannabis in the month prior to 90-day post-treatment follow-up.</p> <p>Conclusion</p> <p>More public health information is needed on cannabis dependence and increased availability of subsidised early and brief interventions in a variety of primary health care settings would reduce the late presentations of the more severely impaired voluntary clients. The limitations of this dataset are discussed.</p
Emerging issues and challenges in agri-food supply chain
Globalization and free trade policies coupled with consumers’ demand for safe and high quality
foods have created pressure on various stakeholders (key players) attached within the agri-food
supply chain. Influence, contributions and the role of socio-economic and environmental factors
are huge to achieve a successful flow of supply chain. Globally, various techniques and
conceptual models have been proposed to render agri-food supply chain to be effective and
profitable. However, still there are several gaps and emerging challenges in the supply chain to
achieve a fruitful sustainable food production. In this chapter, an attempt has been made to
identify and highlight the present world scenario and challenges encountered along agri-food
supply chain and future prospects.This chapter theme article is based on our ongoing project- VALORTECH, which has
received funding from the European Union’s Horizon 2020 research and innovation program under grant
agreement No 810630
A model of HIV/AIDS population dynamics including ARV treatment and pre-exposure prophylaxis
Antiretroviral treatment (ART) and oral pre-exposure prophylaxis (PrEP) have recently
been used efficiently in management of HIV infection. Pre-exposure prophylaxis
consists in the use of an antiretroviral medication to prevent the acquisition of HIV
infection by uninfected individuals. We propose a new model for the transmission of
HIV/AIDS including ART and PrEP. Our model can be used to test the effects of ART
and of the uptake of PrEP in a given population, as we demonstrate through
simulations. The model can also be used to estimate future projections of HIV
prevalence. We prove global stability of the disease-free equilibrium. We also prove
global stability of the endemic equilibrium for the most general case of the model, i.e.,
which allows for PrEP individuals to default. We include insightful simulations based
on recently published South-African data
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