2,449 research outputs found

    The concealed Caledonide basement of eastern England and the southern North Sea : a review

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    Field mapping, analysis of borehole core and studies of geophysical potential field and seismic data can be used to demonstrate the existence of a number of distinct crustal blocks within Eastern Avalonia beneath eastern England and the southern North Sea. At the core of these blocks is the Midlands Microcraton which is flanked by Ordovician volcanic arc complexes exposed in Wales and the Lake District. A possible volcanic arc complex of comparable age in eastern England is concealed by late Palaeozoic and Mesozoic cover. These volcanic arc complexes resulted from subduction of oceanic lithosphere beneath Avalonia prior to collision with Baltica and Laurentia in late Ordovician and Silurian time, respectively. The nature of the crust north and east of the concealed Caledonides of Eastern England and south of the lapetus Suture/Tornquist Sea Suture, which forms the basement to the southern North Sea, is unclear. Late Ordovician metamorphic ages from cores penetrating deformed metasedimentary rocks on the Mid-North Sea High suggest these rocks were involved in Avalonia-Baltica collision before final closure of the lapetus Ocean between Laurentia and Avalonia

    Oxidation processes in magneto-optic and related materials

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    The surface oxidation processes of thin films of magneto-optic materials, such as the rare-earth transition metal alloys have been studied, starting in ultrahigh vacuum environments, using surface analysis techniques, as a way of modeling the oxidation processes which occur at the base of a defect in an overcoated material, at the instant of exposure to ambient environments. Materials examined have included FeTbCo alloys, as well as those same materials with low percentages of added elements, such a Ta, and their reactivities to both O2 and H2O compared with materials such as thin Fe films coated with ultrathin adlayers of Ti. The surface oxidation pathways for these materials is reviewed, and XPS data presented which indicates the type of oxides formed, and a critical region of Ta concentration which provides optimum protection

    Multi-pulse addressing of a Raman quantum memory: configurable beam splitting and efficient readout

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    Quantum memories are vital to the scalability of photonic quantum information processing (PQIP), since the storage of photons enables repeat-until-success strategies. On the other hand the key element of all PQIP architectures is the beam splitter, which allows to coherently couple optical modes. Here we show how to combine these crucial functionalities by addressing a Raman quantum memory with multiple control pulses. The result is a coherent optical storage device with an extremely large time-bandwidth product, that functions as an array of dynamically configurable beam splitters, and that can be read out with arbitrarily high efficiency. Networks of such devices would allow fully scalable PQIP, with applications in quantum computation, long-distance quantum communications and quantum metrology.Comment: 4 pages, 3 figure

    Exposure with acceptance-based versus habituation-based rationale for public speaking anxiety

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    Social Anxiety Disorder (SAD) is a potentially debilitating condition affecting approximately 12% of the population at some point in their life (Ruscio et al., 2008). SAD is divided into two subtypes: generalized and nongeneralized. Nongeneralized SAD refers to individuals whose fears are limited to one or two social situations, most commonly public speaking. Empirically supported treatments for public speaking anxiety generally include an exposure component (usually in vivo/simulated exposure). Exposure is often presented within the context of a habituation rationale, but cognitively- based therapies utilize a rationale for exposure based on cognitive restructuring and belief modification. Research investigating the incremental benefit of adding other treatment components to exposure has yielded mixed results; however, there is preliminary evidence that the context in which exposure is presented can have an impact on treatment outcome. Recently, acceptance-based therapies have begun to frame exposure as an opportunity to increase one’s willingness to experience anxiety while engaging in valued behaviors, rather than as a vehicle for modifying maladaptive cognitions and reducing anxiety. However, little research has been conducted on the efficacy of acceptance-based therapies for public speaking anxiety, and no component control studies have examined the utility of an acceptance/cognitive defusion rationale and context for exposure. The present study compared exposure within an acceptance/defusion context to exposure with a habituation-based rationale in the treatment of public speaking anxiety. Treatment was delivered in a group format over 6 weekly sessions. The hypothesis of superior outcomes for the acceptance-based group was not supported by the data; no significant differences were found between the two treatment conditions. All participants improved on outcome measures of social/public speaking anxiety and speech quality (social skills).Ph.D., Clinical Psychology -- Drexel University, 201

    Patterns of extrapulmonary metastases in sarcoma surveillance

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    Soft tissue sarcomas (STS) most commonly metastasize to the lungs. Current surveillance guidelines variably recommend abdominal and pelvic imaging, but there is little evidence to support this. We sought to determine the proportion of initial pulmonary versus extrapulmonary metastases, the time to development of each, and factors to identify patients that would benefit from abdominopelvic surveillance. We retrospectively reviewed 382 patients who underwent surgical treatment for STS at a single institution. Of the 33% (126/382) of patients who developed metastases, 72% (90/126) were pulmonary, 22% (28/126) were extrapulmonary, and 6% (8/126) developed both simultaneously. Initial extrapulmonary metastases occurred later (log ran

    Conformational variability of the glycine receptor M2 domain in response to activation by different agonists

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    Models describing the structural changes mediating cys-loop receptor activation generally give little attention to the possibility that different agonists may promote activation via distinct M2 pore-lining domain structural rearrangements. We investigated this question by comparing the effects of different ligands on the conformation of the external portion of the homomeric α1 glycine receptor M2 domain. Conformational flexibility was assessed by tethering a rhodamine fluorophore to cysteines introduced at the 19’ or 22’ positions and monitoring fluorescence and current changes during channel activation. During glycine activation, fluorescence of the label attached to R19’C increased by ~20% and the emission peak shifted to lower wavelengths, consistent with a more hydrophobic fluorophore environment. In contrast, ivermectin activated the receptors without producing a fluorescence change. Although taurine and β-alanine were weak partial agonists at the a1R19’C GlyR, they induced large fluorescence changes. Propofol, which drastically enhanced these currents, did not induce a glycine-like blue-shift in the spectral emission peak. The inhibitors, strychnine and picrotoxin, elicited fluorescence and current changes as expected for a competitive antagonist and an open channel blocker, respectively. Glycine and taurine (or β-alanine) also produced an increase and a decrease, respectively, in the fluorescence of a label attached to the nearby L22’C residue. Thus, results from two separate labelled residues support the conclusion that the GlyR M2 domain responds with distinct conformational changes to activation by different agonists

    The impact of leadership development on GP mental health commissioning.

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    Purpose This paper aims to explore the learning needs of general practitioners (GPs) involved in commissioning mental health provision in England, and offer an evaluation of a leadership and commissioning skills development programme for Mental Health Commissioners. Design/methodology/approach Retrospective mixed method, including online mixed method survey, rating participants' knowledge, skills, abilities, semi-structured telephone interviews and third-party questionnaires were used. Results were analysed for significant differences using the Wilcoxon Signed Ranks test. Open-ended responses and interview transcripts were analysed thematically. Findings Indicative results showed that participants perceived significant impacts in ability across eight key question groups evaluated. Differences were found between the perceived and observed impact in relation to technical areas covered within the programme which were perceived as the highest scoring impacts by participants. Research limitations/implications The indicative results show a positive impact on practice has been both perceived and observed. Findings illustrate the value of this development programme on both the personal development of GP Mental Health Commissioners and commissioning practice. Although the findings of this evaluation increase understanding in relation to an important and topical area, larger scale, prospective evaluations are required. Impact evaluations could be embedded within future programmes to encourage higher participant and third-party engagement. Future evaluations would benefit from collection and analysis of attendance data. Further research could involve patient, service user and carer perspectives on mental health commissioning. Originality value Results of this evaluation could inform the development of future learning programmes for mental health commissioners as part of a national approach to improve mental health provision

    Granulocyte-colony stimulating factor in experimental stroke and its effects on infarct size and functional outcome: a systematic review

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    Background Granulocyte-colony stimulating factor (G-CSF) shows promise as a treatment for stroke. This systematic review assesses G-CSF in experimental ischaemic stroke. Methods Relevant studies were identified with searches of Medline, Embase and PubMed. Data were extracted on stroke lesion size, neurological outcome and quality, and analysed using Cochrane Review Manager using random effects models; results are expressed as standardised mean difference (SMD) and odds ratio (OR). Results Data were included from 19 publications incorporating 666 animals. G-CSF reduced lesion size significantly in transient (SMD -1.63, p4 weeks post ischaemia) was not (SMD 0.76, p=0.35). Death (OR 0.27, p<0.0001) was reduced with G-CSF. Median study quality was 4 (range 0-7/8); Egger’s test suggested significant publication bias (p=0.001). Conclusions G-CSF significantly reduced lesion size in transient but not permanent models of ischaemic stroke. Motor impairment and death were also reduced. Further studies assessing dose-response, administration time, length of ischaemia and long-term functional recovery are needed
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