3,988 research outputs found

    The needs of stakeholders in the formation of a local children's university : an exploration through grounded theory of participant drivers and their underpinning features

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    There are over ninety local Children’s Universities (CUs) throughout the United Kingdom and overseas. CUs aim to recognise the learning needs of children which are met through extracurricular and out of school provision. The performance of some local CUs has been evaluated for the National Children’s University on an annual basis. There has never been a detailed exploration of factors underpinning the needs of stakeholders, including children, teachers, teacher education students and Higher Education tutors, involved in the formation of a local CU. The aim of this research was to identify motives for stakeholder participation in the local CU, to discover their needs and identify issues that contributed to those needs. This qualitative study used open, unstructured individual and focus group interviews with stakeholders using a constructivist grounded theory approach. The research identified that the unique approach by this CU benefited learners at several levels of development by providing a context within which children, teachers, teacher education students and Higher Education (HE) tutors could learn in a less formal way than in standard school practice. There was informal acquisition of knowledge and skills by children, continuing professional development for teachers and modelling of effective practice to teacher education students by their tutor. Teachers described the pedagogy adopted as innovative. They considered the tutor as a trusted expert who was able to support their professional development. Tutor credibility was enhanced in the eyes of the teacher education students who valued the opportunity to observe their tutor teaching children rather than just modelling it to them. These views were upheld in comments made by other education-related professionals, by school governors and by parents. Findings have implications for the professional development of teachers. They are relevant to current moves to ‘train’ new teachers in schools. This approach, with more emphasis on non-formal learning, is valued by students and by teachers but the latter, in particular, value the presence of someone with expertise to moderate the process

    Enhancing the efficacy of 5-HT uptake inhibitors in the treatment of attention deficit hyperactivity disorder

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    Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common childhood behavioural disorders, the frontline treatments for which are drugs with abuse potential. As a consequence, there is an urgent need to develop non addictive drug treatments with equivalent efficacy. Preclinical evidence suggests that selective serotonin uptake inhibitors (SSRIs) are likely to be effective in ADHD, however clinical reports suggest that SSRIs are of limited therapeutic value for the treatment of ADHD. We propose that this disconnect can be explained by the pattern of drug administration in existing clinical trials (administration for short periods of time, or intermittently) leading to inadequate control of the autoregulatory processes which control 5-HT release, most notably at the level of inhibitory 5-HT1A somatodendritic autoreceptors. These autoreceptors reduce the firing rate of 5-HT neurons (limiting release) unless they are desensitised by a long term, frequent pattern of drug administration. As such, we argue that the participants in earlier trials were not administered SSRIs in a manner which realises any potential benefits of targeting 5-HT in the pharmacotherapy of ADHD. In light of this, we hypothesise that there may be under-researched potential to exploit 5-HT transmission therapeutically in ADHD, either through changing the administration regime, or by pharmacological means. Recent pharmacological research has successfully potentiated the effects of SSRIs in acute animal preparations by antagonising inhibitory 5-HT1A autoreceptors prior to the administration of the SSRI fluoxetine. We suggest that combination therapies linking SSRIs and 5-HT1A antagonists are a potential way forward in the development of efficacious non-addictive pharmacotherapies for ADHD

    On Properties of Univariate Max Functions at Local Maximizers

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    High temperature power electronics for space

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    A high temperature electronics program at NASA Lewis Research Center focuses on dielectric and insulating materials research, development and testing of high temperature power components, and integration of the developed components and devices into a demonstrable 200 C power system, such as inverter. An overview of the program and a description of the in-house high temperature facilities along with experimental data obtained on high temperature materials are presented

    Electrical characterization of glass, teflon, and tantalum capacitors at high temperatures

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    Dielectric materials and electrical components and devices employed in radiation fields and the space environment are often exposed to elevated temperatures among other things. Therefore, these systems must withstand the high temperature exposure while still providing good electrical and other functional properties. Experiments were carried out to evaluate glass, teflon, and tantalum capacitors for potential use in high temperature applications. The capacitors were characterized in terms of their capacitance and dielectric loss as a function of temperature up to 200 C. At a given temperature, these properties were obtained in a frequency range of 50 Hz to 100 kHz. The DC leakage current measurements were also performed in a temperature range from 20 to 200 C. The obtained results are discussed and conclusions are made concerning the suitability of the capacitors investigated for high temperature applications

    Electrical properties of teflon and ceramic capacitors at high temperatures

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    Space power systems and components are often required to operate efficiently and reliably in harsh environments where stresses, such as high temperature, are encountered. These systems must, therefore, withstand exposure to high temperature while still providing good electrical and other functional properties. Experiments were carried out to evaluate Teflon and ceramic capacitors for potential use in high temperature applications. The capacitors were characterized in terms of their capacitance and dielectric loss as a function of temperature, up to 200 C. At a given temperature, these properties were obtained in a frequency range of 50 Hz to 100 kHz. DC leakage current measurements were also performed in a temperature range from 25 to 200 C. The results obtained are discussed and conclusions are made concerning the suitability of the capacitors studied for high temperature applications

    The relationship between ADHD traits and sensory sensitivity in the general population

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    Preliminary studies in children and adults with Attention Deficit Hyperactivity Disorder (ADHD) report both hypo-responsiveness and hyper-responsiveness to sensory stimuli, as well as problems modulating sensory input. As it has been suggested that those with ADHD exist at the extreme end of a continuum of ADHD traits, which are also evident in the general population, we investigated the link between ADHD and sensory sensitivity in the general population. Two online questionnaires measuring ADHD traits and sensory responsivity across various sensory domains were administered to 234 participants. Results showed a highly significant positive correlation between the number of ADHD traits and the frequency of reported sensory processing problems. An increased number of sensory difficulties across all modalities was associated with the level of ADHD. Furthermore, ADHD traits predicted sensory difficulties and exploratory factor analysis revealed a factor that combined ADHD trait and sensory processing items. This is the first study to identify a positive relationship between sensory processing and ADHD traits in the general population. Our results suggest that sensory difficulties could be part of the ADHD phenotype

    Increased microsaccade rate in individuals with ADHD traits

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    Microsaccades are involuntary, small, jerk-like eye-movements with high-velocity that are observed during fixation. Abnormal microsaccade rates and characteristics have been observed in a number of psychiatric and developmental disorders. In this study, we examine microsaccade differences in 43 non-clinical participants with high and low levels of ADHD-like traits, assessed with the Adult ADHD Self-Report Scale (ASRS, Kessler, Adler, et al., 2005). A simple sustained attention paradigm, which has been previously shown to elicit microsaccades, was employed. A positive correlation was found between ADHD-like traits and binocular and monocular microsaccade rates. No other differences in microsaccade properties were observed. The relationship between ADHD traits and microsaccades suggests that abnormal oculomotor behaviour is a core deficit in ADHD and could potentially lead to the development of a biomarker for the disorder

    An Improved Private Mechanism for Small Databases

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    We study the problem of answering a workload of linear queries Q\mathcal{Q}, on a database of size at most n=o(Q)n = o(|\mathcal{Q}|) drawn from a universe U\mathcal{U} under the constraint of (approximate) differential privacy. Nikolov, Talwar, and Zhang~\cite{NTZ} proposed an efficient mechanism that, for any given Q\mathcal{Q} and nn, answers the queries with average error that is at most a factor polynomial in logQ\log |\mathcal{Q}| and logU\log |\mathcal{U}| worse than the best possible. Here we improve on this guarantee and give a mechanism whose competitiveness ratio is at most polynomial in logn\log n and logU\log |\mathcal{U}|, and has no dependence on Q|\mathcal{Q}|. Our mechanism is based on the projection mechanism of Nikolov, Talwar, and Zhang, but in place of an ad-hoc noise distribution, we use a distribution which is in a sense optimal for the projection mechanism, and analyze it using convex duality and the restricted invertibility principle.Comment: To appear in ICALP 2015, Track
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