99 research outputs found

    High performance extendable instruction set computing

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    In this paper, a new architecture called the extendable instruction set computer (EISC) is introduced that addresses the issues of memory size and performance in embedded microprocessor systems. The architecture exhibits an efficient fixed length 16-bit instruction set with short length offset and immediate operands. The offset and immediate operands can be extended to 32 bits via the operation of an extension flag. The code density of the EISC instruction set and its memory transfer erformance is shown to be significantly higher than current architectures making it a suitable candidate for the next generation of embedded computer systems. The compact EISC instruction set introduces data dependencies that seemingly limit deep pipeline and superscalar implementations. This paper suggests a mechanism by which these dependencies might be removed in hardware

    Development of an internationally agreed minimal dataset for juvenile dermatomyositis (JDM) for clinical and research use

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    Background: Juvenile dermatomyositis (JDM) is a rare autoimmune inflammatory disorder associated with significant morbidity and mortality. International collaboration is necessary to better understand the pathogenesis of the disease, response to treatment and long-term outcome. To aid international collaboration, it is essential to have a core set of data that all researchers and clinicians collect in a standardised way for clinical purposes and for research. This should include demographic details, diagnostic data and measures of disease activity, investigations and treatment. Variables in existing clinical registries have been compared to produce a provisional data set for JDM. We now aim to develop this into a consensus-approved minimum core dataset, tested in a wider setting, with the objective of achieving international agreement. Methods/Design: A two-stage bespoke Delphi-process will engage the opinion of a large number of key stakeholders through Email distribution via established international paediatric rheumatology and myositis organisations. This, together with a formalised patient/parent participation process will help inform a consensus meeting of international experts that will utilise a nominal group technique (NGT). The resulting proposed minimal dataset will be tested for feasibility within existing database infrastructures. The developed minimal dataset will be sent to all internationally representative collaborators for final comment. The participants of the expert consensus group will be asked to draw together these comments, ratify and 'sign off' the final minimal dataset. Discussion: An internationally agreed minimal dataset has the potential to significantly enhance collaboration, allow effective communication between groups, provide a minimal standard of care and enable analysis of the largest possible number of JDM patients to provide a greater understanding of this disease. The final approved minimum core dataset could be rapidly incorporated into national and international collaborative efforts, including existing prospective databases, and be available for use in randomised controlled trials and for treatment/protocol comparisons in cohort studies

    Impact of asymmetries on fuel performance in inertial confinement fusion

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    Low-mode asymmetries prevent effective compression, confinement, and heating of the fuel in inertial confinement fusion (ICF) implosions, and their control is essential to achieving ignition. Ion temperatures (Tion) in ICF experiments are inferred from the broadening of primary neutron spectra. Directional motion (flow) of the fuel at burn also impacts broadening and will lead to artificially inflated "Tion" values. Flow due to low-mode asymmetries is expected to give rise to line-of-sight variations in measured Tion. We report on intentionally asymmetrically driven experiments at the OMEGA laser facility designed to test the ability to accurately predict and measure line-of-sight differences in apparent Tion due to low-mode asymmetry-seeded flows. Contrasted to chimera and xrage simulations, the measurements demonstrate how all asymmetry seeds have to be considered to fully capture the flow field in an implosion. In particular, flow induced by the stalk that holds the target is found to interfere with the seeded asymmetry. A substantial stalk-seeded asymmetry in the areal density of the implosion is also observed

    Increased ion temperature and neutron yield observed in magnetized indirectly driven D_{2}-filled capsule implosions on the national ignition facility

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    The application of an external 26 Tesla axial magnetic field to a D_{2} gas-filled capsule indirectly driven on the National Ignition Facility is observed to increase the ion temperature by 40% and the neutron yield by a factor of 3.2 in a hot spot with areal density and temperature approaching what is required for fusion ignition [1]. The improvements are determined from energy spectral measurements of the 2.45 MeV neutrons from the D(d,n)^{3}He reaction, and the compressed central core B field is estimated to be ∼4.9  kT using the 14.1 MeV secondary neutrons from the D(T,n)^{4}He reactions. The experiments use a 30 kV pulsed-power system to deliver a ∼3  μs current pulse to a solenoidal coil wrapped around a novel high-electrical-resistivity AuTa_{4} hohlraum. Radiation magnetohydrodynamic simulations are consistent with the experiment

    A web-based, peer-supported self-management intervention to reduce distress in relatives of people with psychosis or bipolar disorder:the REACT RCT

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    BACKGROUND: Relatives caring for people with severe mental health problems find information and emotional support hard to access. Online support for self-management offers a potential solution. OBJECTIVE: The objective was to determine the clinical effectiveness and cost-effectiveness of an online supported self-management tool for relatives: the Relatives' Education And Coping Toolkit (REACT). DESIGN AND SETTING: This was a primarily online (UK), single-blind, randomised controlled trial, comparing REACT plus a resource directory and treatment as usual with the resource directory and treatment as usual only, by measuring user distress and other well-being measures at baseline and at 12 and 24 weeks. PARTICIPANTS: A total of 800 relatives of people with severe mental health problems across the UK took part; relatives who were aged ≥ 16 years, were experiencing high levels of distress, had access to the internet and were actively seeking help were recruited. INTERVENTION: REACT comprised 12 psychoeducation modules, peer support through a group forum, confidential messaging and a comprehensive resource directory of national support. Trained relatives moderated the forum and responded to messages. MAIN OUTCOME MEASURE: The main outcome was the level of participants' distress, as measured by the General Health Questionnaire-28 items. RESULTS: Various online and offline strategies, including social media, directed potential participants to the website. Participants were randomised to one of two arms: REACT plus the resource directory (n = 399) or the resource directory only (n = 401). Retention at 24 weeks was 75% (REACT arm, n = 292; resource directory-only arm, n = 307). The mean scores for the General Health Questionnaire-28 items reduced substantially across both arms over 24 weeks, from 40.2 (standard deviation 14.3) to 30.5 (standard deviation 15.6), with no significant difference between arms (mean difference -1.39, 95% confidence interval -3.60 to 0.83; p = 0.22). At 12 weeks, the General Health Questionnaire-28 items scores were lower in the REACT arm than in the resource directory-only arm (-2.08, 95% confidence interval -4.14 to -0.03; p = 0.027), but this finding is likely to be of limited clinical significance. Accounting for missing data, which were associated with higher distress in the REACT arm (0.33, 95% confidence interval -0.27 to 0.93; p = 0.279), in a longitudinal model, there was no significant difference between arms over 24 weeks (-0.56, 95% confidence interval -2.34 to 1.22; p = 0.51). REACT cost £142.95 per participant to design and deliver (£62.27 for delivery only), compared with £0.84 for the resource directory only. A health economic analysis of NHS, health and Personal Social Services outcomes found that REACT has higher costs (£286.77), slightly better General Health Questionnaire-28 items scores (incremental General Health Questionnaire-28 items score adjusted for baseline, age and gender: -1.152, 95% confidence interval -3.370 to 1.065) and slightly lower quality-adjusted life-year gains than the resource directory only; none of these differences was statistically significant. The median time spent online was 50.8 minutes (interquartile range 12.4-172.1 minutes) for REACT, with no significant association with outcome. Participants reported finding REACT a safe, confidential environment (96%) and reported feeling supported by the forum (89%) and the REACT supporters (86%). No serious adverse events were reported. LIMITATIONS: The sample comprised predominantly white British females, 25% of participants were lost to follow-up and dropout in the REACT arm was not random. CONCLUSIONS: An online self-management support toolkit with a moderated group forum is acceptable to relatives and, compared with face-to-face programmes, offers inexpensive, safe delivery of National Institute for Health and Care Excellence-recommended support to engage relatives as peers in care delivery. However, currently, REACT plus the resource directory is no more effective at reducing relatives' distress than the resource directory only. FUTURE WORK: Further research in improving the effectiveness of online carer support interventions is required. TRIAL REGISTRATION: Current Controlled Trials ISRCTN72019945. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 32. See the NIHR Journals Library website for further project information. Relatives of people with severe mental health problems need better access to information and emotional support. The Relatives’ Education And Coping Toolkit (REACT) is a website designed to do this. It includes lots of information presented in text and video, an online forum for relatives to share knowledge and experience, a messaging system where they can ask questions in confidence and a comprehensive directory of contact details for national organisations offering relevant support. Trained relatives support the forum and messaging. In the UK, we recruited 800 relatives of people with severe mental health problems: all were aged ≥ 16 years, had high levels of distress, had access to the internet and wanted help. We divided them into two equal groups: one group received REACT (including the resource directory), whereas the other group received the resource directory only. To ensure that there were no differences between groups at the start, relatives were allocated to the two groups randomly, so they had an equal chance of being in either group. We followed up with both groups at 12 and 24 weeks, and received data from approximately three-quarters of the participants. This trial found that REACT was acceptable, safe and inexpensive to deliver (£62.27 per relative), compared with face-to-face interventions, and that relatives using it felt well supported. However, once we accounted for missing data (relatives who dropped out of the trial or did not complete the follow-up questionnaires), there were no significant differences between the groups. There was no evidence that REACT increased relatives’ quality of life or saved money for the NHS

    Global Analysis of Quorum Sensing Targets in the Intracellular Pathogen Brucella melitensis 16 M

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    Many pathogenic bacteria use a regulatory process termed quorum sensing (QS) to produce and detect small diffusible molecules to synchronize gene expression within a population. In Gram-negative bacteria, the detection of, and response to, these molecules depends on transcriptional regulators belonging to the LuxR family. Such a system has been discovered in the intracellular pathogen Brucella melitensis, a Gram-negative bacterium responsible for brucellosis, a worldwide zoonosis that remains a serious public health concern in countries were the disease is endemic. Genes encoding two LuxR-type regulators, VjbR and BabR, have been identified in the genome of B. melitensis 16 M. A DeltavjbR mutant is highly attenuated in all experimental models of infection tested, suggesting a crucial role for QS in the virulence of Brucella. At present, no function has been attributed to BabR. The experiments described in this report indicate that 5% of the genes in the B. melitensis 16 M genome are regulated by VjbR and/or BabR, suggesting that QS is a global regulatory system in this bacterium. The overlap between BabR and VjbR targets suggest a cross-talk between these two regulators. Our results also demonstrate that VjbR and BabR regulate many genes and/or proteins involved in stress response, metabolism, and virulence, including those potentially involved in the adaptation of Brucella to the oxidative, pH, and nutritional stresses encountered within the host. These findings highlight the involvement of QS as a major regulatory system in Brucella and lead us to suggest that this regulatory system could participate in the spatial and sequential adaptation of Brucella strains to the host environment.Journal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe

    Search for hyperdeformation in U isotopes

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    The U-232 nucleus was studied in order to search for a hyperdeformed band built upon the third minimum of the fission barrier. Upper limits for the percentage population of a hypothetical hyperdeformed band relative to the ground state band are given
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