209 research outputs found

    High-density Au nanorod optical field-emitter arrays

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    We demonstrate the design, fabrication, characterization, and operation of high-density arrays of Au nanorod electron emitters, fabricated by high-resolution electron beam lithography, and excited by ultrafast femtosecond near-infrared radiation. Electron emission characteristic of multiphoton absorption has been observed at low laser fluence, as indicated by the power-law scaling of emission current with applied optical power. The onset of space-charge-limited current and strong optical field emission has been investigated so as to determine the mechanism of electron emission at high incident laser fluence. Laser-induced structural damage has been observed at applied optical fields above 5 GV m[superscript −1], and energy spectra of emitted electrons have been measured using an electron time-of-flight spectrometer.United States. Defense Advanced Research Projects Agency (Contract N66001-11-1-4192)Gordon and Betty Moore Foundatio

    Public opinion on energy crops in the landscape: considerations for the expansion of renewable energy from biomass

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    Public attitudes were assessed towards two dedicated biomass crops – Miscanthus and Short Rotation Coppice (SRC), particularly regarding their visual impacts in the landscape. Results are based on responses to photographic and computer-generated images as the crops are still relatively scarce in the landscape. A questionnaire survey indicated little public concern about potential landscape aesthetics but more concern about attendant built infrastructure. Focus group meetings and interviews indicated support for biomass end uses that bring direct benefits to local communities. Questions arise as to how well the imagery used was able to portray the true nature of these tall, dense, perennial plants but based on the responses obtained and given the caveat that there was limited personal experience of the crops, it appears unlikely that wide-scale planting of biomass crops will give rise to substantial public concern in relation to their visual impact in the landscape

    Loop Interactions during Catalysis by Dihydrofolate Reductase fromMoritella profunda

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    Dihydrofolate reductase (DHFR) is often used as a model system to study the relation between protein dynamics and catalysis. We have studied a number of variants of the cold-adapted DHFR from Moritella profunda (MpDHFR), in which the catalytically important M20 and FG loops have been altered, and present a comparison with the corresponding variants of the wellstudied DHFR from Escherichia coli (EcDHFR). Mutations in the M20 loop do not affect the actual chemical step of transfer of hydride from reduced nicotinamide adenine dinucleotide phosphate to the substrate 7,8-dihydrofolate in the catalytic cycle in either enzyme; they affect the steady state turnover rate in EcDHFR but not in MpDHFR. Mutations in the FG loop also have different effects on catalysis by the two DHFRs. Despite the two enzymes most likely sharing a common catalytic cycle at pH 7, motions of these loops, known to be important for progression through the catalytic cycle in EcDHFR, appear not to play a significant role in MpDHFR

    The Policy and Practice of Music Education in England, 2010-2020

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    Since the introduction of the National Plan for Music Education there have been significant changes in music education within England. Whilst some celebrate figures that report increased access and engagement, many teachers and others continue to have legitimate concerns regarding the quality of the music education on offer in schools and Music Education Hubs. There are concerns that the provision of music education is incoherent and patchy across the country. Many would argue that the opportunity to access high‐quality music education has become a ‘postcode lottery’. There is a sense that the fragmentation of music education as a result of curriculum reforms and the diversity of approaches taken by Music Education Hubs and other bodies has significantly enhanced this incoherence. This article seeks to review the policy and practice of music education in England over the last 10 years. It draws on recent research from various sources and maintains a particular focus on government policy and the consequences of this for the field as a whole. It reflects on how things could be improved in the future. It argues for a clearer focus on a practitioner‐led approach to research and advocacy, in particular one led by the notion of ‘policy as practice’ rather than continuing with the current approach and its intrinsic failings

    The educational impact of assessment: a comparison of DOPS and MCQs

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    Aim: To evaluate the impact of two different assessment formats on the approaches to learning of final year veterinary students. The relationship between approach to learning and examination performance was also investigated. Method: An 18-item version of the Study Process Questionnaire (SPQ) was sent to 87 final year students. Each student responded to the questionnaire with regards to DOPS (Direct Observation of Procedural Skills) and a Multiple Choice Examination (MCQ). Semi-structured interviews were conducted with 16 of the respondents to gain a deeper insight into the students’ perception of assessment. Results: Students’ adopted a deeper approach to learning for DOPS and a more surface approach with MCQs. There was a positive correlation between an achieving approach to learning and examination performance. Analysis of the qualitative data revealed that deep, surface and achieving approaches were reported by the students and seven major influences on their approaches to learning were identified: motivation, purpose, consequence, acceptability, feedback, time pressure and the individual difference of the students. Conclusions: The format of DOPS has a positive influence on approaches to learning. There is a conflict for students between preparing for final examinations and preparing for clinical practice

    Popular music and school music education: Chinese students' preferences and dilemmas in Shanghai, China

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    This empirical study investigates Chinese students’ popular music preferences in daily life and to what extent and in what ways they prefer learning popular music in school in Shanghai, China. Data were drawn from questionnaires completed by 1,730 secondary students (aged 12–17) and interviews with 60 students from 10 secondary schools, between September and October, 2011. Findings from these efforts were supplemented by and triangulated with data from interviews with 18 music teachers and school leaders. Findings revealed the cultural diversification and rational consumption of popular music by Chinese students in and out of school, as well as the cultural dilemmas those students confront due to their preferences for popular (Chinese and non-Chinese) and classical music in the school music curriculum. These findings can be interpreted as indicating that music and music education in formal or informal settings are complex cultural constructs that can be reinvented through the intertwined interplay of different actors concerned with the selection of music elements in a multileveled, multicultural world.postprin

    Using video-reflexive ethnography to capture the complexity of leadership enactment in the healthcare workplace

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    This research was part of LG’s Ph.D. research which was generously funded by NHS Education for Scotland through SMERC.Current theoretical thinking asserts that leadership should be distributed across many levels of healthcare organisations to improve the patient experience and staff morale. However, much healthcare leadership education focusses on the training and competence of individuals and little attention is paid to the interprofessional workplace and how its inherent complexities might contribute to the emergence of leadership. Underpinned by complexity theory, this research aimed to explore how interprofessional healthcare teams enact leadership at a micro-level through influential acts of organising. A whole (interprofessional) team workplace-based study utilising video-reflexive ethnography occurred in two UK clinical sites. Thematic framework analyses of the video data (video-observation and video-reflexivity sessions) were undertaken, followed by in-depth analyses of human–human and human–material interactions. Data analysis revealed a complex interprofessional environment where leadership is a dynamic process, negotiated and renegotiated in various ways throughout interactions (both formal and informal). Being able to “see” themselves at work gave participants the opportunity to discuss and analyse their everyday leadership practices and challenge some of their sometimes deeply entrenched values, beliefs, practices and assumptions about healthcare leadership. These study findings therefore indicate a need to redefine the way that medical and healthcare educators facilitate leadership development and argue for new approaches to research which shifts the focus from leaders to leadership.Publisher PDFPeer reviewe

    Thermal Adaptation of Dihydrofolate Reductase from the Moderate ThermophileGeobacillus stearothermophilus

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    The thermal melting temperature of dihydrofolate reductase from Geobacillus stearothermophilus (BsDHFR) is 30 °C higher than that of its homologue from the psychrophile Moritella profunda. Additional proline residues in the loop regions of BsDHFR have been proposed to enhance the thermostability of BsDHFR, but site-directed mutagenesis studies reveal that these proline residues contribute only minimally. Instead, the high thermal stability of BsDHFR is partly due to removal of water-accessible thermolabile residues such as glutamine and methionine, which are prone to hydrolysis or oxidation at high temperatures. The extra thermostability of BsDHFR can be obtained by ligand binding, or in the presence of salts or cosolvents such as glycerol and sucrose. The sum of all these incremental factors allows BsDHFR to function efficiently in the natural habitat of G. stearothermophilus, which is characterized by temperatures that can reach 75 °C

    Animal model integration to AutDB, a genetic database for autism

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    <p>Abstract</p> <p>Background</p> <p>In the post-genomic era, multi-faceted research on complex disorders such as autism has generated diverse types of molecular information related to its pathogenesis. The rapid accumulation of putative candidate genes/loci for Autism Spectrum Disorders (ASD) and ASD-related animal models poses a major challenge for systematic analysis of their content. We previously created the Autism Database (AutDB) to provide a publicly available web portal for ongoing collection, manual annotation, and visualization of genes linked to ASD. Here, we describe the design, development, and integration of a new module within AutDB for ongoing collection and comprehensive cataloguing of ASD-related animal models.</p> <p>Description</p> <p>As with the original AutDB, all data is extracted from published, peer-reviewed scientific literature. Animal models are annotated with a new standardized vocabulary of phenotypic terms developed by our researchers which is designed to reflect the diverse clinical manifestations of ASD. The new Animal Model module is seamlessly integrated to AutDB for dissemination of diverse information related to ASD. Animal model entries within the new module are linked to corresponding candidate genes in the original "Human Gene" module of the resource, thereby allowing for cross-modal navigation between gene models and human gene studies. Although the current release of the Animal Model module is restricted to mouse models, it was designed with an expandable framework which can easily incorporate additional species and non-genetic etiological models of autism in the future.</p> <p>Conclusions</p> <p>Importantly, this modular ASD database provides a platform from which data mining, bioinformatics, and/or computational biology strategies may be adopted to develop predictive disease models that may offer further insights into the molecular underpinnings of this disorder. It also serves as a general model for disease-driven databases curating phenotypic characteristics of corresponding animal models.</p
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