26,831 research outputs found

    Comparison of some chemical and non-chemical treatments to disinfect a recirculating nutrient solution

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    Closed hydroponic growing systems have a better water use efficiency (WUE) and a lower use of fertilizers, but a larger risk of spreading soil-borne pathogens all over the crop compared to open systems. In climates or regions where availability of water is limited closed systems should be preferred above open systems but the risk of spreading soil-borne pathogens should be minimized. Disinfection of the nutrient solution is a valuable method, but it often demands high investments. A desk study was made to compare the performance of some chemical and non-chemical treatments. For larger companies (>2 ha) heat treatment and UV radiation are still the best options. For smaller companies

    Disease management in soilless culture systems

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    EU legislation, laid down in the Water Framework Directive, demands to minimize emissions of nitrogen, phosphate and crop protection products to achieve an excellent chemical and ecological quality in 2015. The aim is to force growers to a better water and disease management. Supply water of excellent chemical quality will have to be recirculated as long as possible, for which adequate disinfection equipment have to be used. Several sources of water are used as supply water. Rainwater is chemically best, followed by reverse osmosis water. However, the latter is rather expensive. Tap water and surface water often have a too high salinity, while well water may vary dramatically from place to place. Rainwater and surface water are potential risk factors for importing soil-borne pathogens. Disinfection of the recirculating nutrient solution can be done adequately by heat treatment and UV radiation. Membrane filtration performs well, but is mostly too costly. Chemical treatments as sodium hypochlorite, chlorine dioxide and copper silver ionization may partly solve the pathogen problem, but introduce a potential accumulation of other elements in closed systems. Hydrogen peroxide, chlorine dioxide and sodium hypochlorite perform better to clean pipe work instead of soil-borne pathogens

    The integrative framework for the behavioural sciences has already been discovered, and it is the adaptationist approach

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    The adaptationist framework is necessary and sufficient for unifying the social and natural sciences. Gintis’s “beliefs, preferences, and constraints” (BPC) model compares unfavorably to this framework because it lacks criteria for determining special design, incorrectly assumes that standard evolutionary theory predicts individual rationality maximisation, does not adequately recognize the impact of psychological mechanisms on culture, and is mute on the behavioural implications of intragenomic conflict

    Fluency in dialogue: Turn‐taking behavior shapes perceived fluency in native and nonnative speech

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    Fluency is an important part of research on second language learning, but most research on language proficiency typically has not included oral fluency as part of interaction, even though natural communication usually occurs in conversations. The present study considered aspects of turn-taking behavior as part of the construct of fluency and investigated whether these aspects differentially influence perceived fluency ratings of native and non-native speech. Results from two experiments using acoustically manipulated speech showed that, in native speech, too ‘eager’ (interrupting a question with a fast answer) and too ‘reluctant’ answers (answering slowly after a long turn gap) negatively affected fluency ratings. However, in non-native speech, only too ‘reluctant’ answers led to lower fluency ratings. Thus, we demonstrate that acoustic properties of dialogue are perceived as part of fluency. By adding to our current understanding of dialogue fluency, these lab-based findings carry implications for language teaching and assessmen

    Computer Modeling of Personal Autonomy and Legal Equilibrium

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    Empirical studies of personal autonomy as state and status of individual freedom, security, and capacity to control own life, particularly by independent legal reasoning, are need dependable models and methods of precise computation. Three simple models of personal autonomy are proposed. The linear model of personal autonomy displays a relation between freedom as an amount of agent's action and responsibility as an amount of legal reaction and shows legal equilibrium, the balance of rights and duties needed for sustainable development of any community. The model algorithm of judge personal autonomy shows that judicial decision making can be partly automated, like other human jobs. Model machine learning of autonomous lawyer robot under operating system constitution illustrates the idea of robot rights. Robots, i.e. material and virtual mechanisms serving the people, deserve some legal guarantees of their rights such as robot rights to exist, proper function and be protected by the law. Robots, actually, are protected as any human property by the wide scope of laws, starting with Article 17 of Universal Declaration of Human Rights, but the current level of human trust in autonomous devices and their role in contemporary society needs stronger legislation to guarantee the robot rights.Comment: 8 pages, 6 figures, presented at Computer Science On-line Conference 201

    A Risk Based Approach for Proactive Asset Management of Sewer Structural Conditions in England and Wales

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    The aim of this research is to create a risk based framework to prioritise proactive investment for sewers in England and Wales. This research proposes a sewer deterioration model that will enhance and not replace the industry’s business as usual process and it also recommends how standard sewer assessment reports can be better utilised to inform business decisions. The methodology used to complete this research project is a mixture of qualitative and quantitative approaches to analyse a total length of 24,252 km which represents 703,156 records of historic sewer structural condition inspection data. This was used to build an improved deterioration model. Proactive investment (future condition prediction) assessments have been made within Thames Water and other wastewater utilities in the UK. The approaches are reviewed, compared, limitation identified and a robust approach was defined, devising means to mitigate the limitations identified. Existing approaches within and outside the industry to assess sewer condition and model sewer deterioration for risk management was reviewed. Data analytical software such as MATLAB and Tibco Spotfire were used to create an intuitive risk framework that will aid sewer investment decision making. An improved deterioration model and inspection frequencies for sewers were developed as a premise for proactive investment. This deterioration model and the inspection frequencies were then used to create a risk based framework to help set proactive priorities for sewer management. This would enable sewerage asset owners with large kilometres of sewers to manage the sewerage system more proactively before they reach a critical point and reduce the reliance on industry expert judgement and further surveys. The improved deterioration model and inspection frequencies provided in this research would enable sewer asset managers to determine the most cost-effective time to invest in repairs or replacement. Also, a plausible and reliable validation that was provided would give a high level of confidence in the risk based framework

    Adherence to prophylaxis in adolescents and young adults with severe haemophilia: a qualitative study with healthcare professionals

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    © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Aim: to examine healthcare professionals’ (HP) perceptions and experiences in relation to adherence to prophylactic treatment among young people living with haemophilia (YPH). Methods: All HPs in four haemophilia centres across England and Wales were invited to participate, and all HPs who agreed to take part (n = 6) were interviewed. Interviews were audio-recorded, transcribed and then analysed using Interpretative Phenomenological Analysis (IPA). Results: HPs estimate that generally young people with haemophilia keep to their treatment regimen well, although they also recognise that adherence may fluctuate with many patients going through shorter periods of non-adherence. The increasingly personalised or flexible approach to prophylaxis makes it harder to assess adherence. The main themes identified through IPA included (1) HPs’ suggest that adherence fluctuates (2) Non-adherence is mainly driven by lifestyle and developmental, social and family factors, and (3) Education, HPs’ sensitivity to individual needs, and psychological and peer support are key facilitators of good adherence. Conclusion: The increasingly flexible approach to prophylaxis requires a new way of thinking about, and assessment of, adherence. More personalised treatment regimen can be more complicated and may, therefore, lead to accidental non-adherence. The results of this study with HPs complement those of a previous qualitative study with patients but place greater emphasis on a broader perspective on understanding drivers of non-adherence as well as understanding strategies to improve adherence in the minority of patients who appear to struggle.Peer reviewedFinal Published versio

    PFTijah: text search in an XML database system

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    This paper introduces the PFTijah system, a text search system that is integrated with an XML/XQuery database management system. We present examples of its use, we explain some of the system internals, and discuss plans for future work. PFTijah is part of the open source release of MonetDB/XQuery
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