4,408 research outputs found

    Evaporation of a packet of quantized vorticity

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    A recent experiment has confirmed the existence of quantized turbulence in superfluid He3-B and suggested that turbulence is inhomogenous and spreads away from the region around the vibrating wire where it is created. To interpret the experiment we study numerically the diffusion of a packet of quantized vortex lines which is initially confined inside a small region of space. We find that reconnections fragment the packet into a gas of small vortex loops which fly away. We determine the time scale of the process and find that it is in order of magnitude agreement with the experiment.Comment: figure 1a,b,c and d, figure2, figure

    Evaluation of the CNS and cardiovascular effects of prolonged exposure to bromotrifluromethane (CBrF3)

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    The proposed use of bromotrifluoromethane (CBrF3) as a fire extinguishant in aircraft, spacecraft and submarines has stimulated increasing interest and research in the toxicological properties of this compound. In a spacecraft, because of its unique recirculating life support system, the introduction of CBrF3 by leakage or intentional discharge, will result in continuous exposure of crewman to low concentrations of this compound for periods of up to 7 days, or possibly even longer. The effects of low concentrations of CBrF3, under continuous exposure conditions, on the CNS and cardiovascular systems of animals to enable an assessment of these risks were investigated

    Specific heat of the Kelvin modes in low temperature superfluid turbulence

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    It is pointed out that the specific heat of helical vortex line excitations, in low temperature superfluid turbulence experiments carried out in helium II, can be of the same order as the specific heat of the phononic quasiparticles. The ratio of Kelvin mode and phonon specific heats scales with L_0 T^{-5/2}, where L_0 represents the smoothed line length per volume within the vortex tangle, such that the contribution of the vortex mode specific heat should be observable for L_0 = 10^6-10^8 cm^{-2}, and at temperatures which are of order 1-10 mK.Comment: 3 pages, 1 figur

    Health research systems in change: the case of ‘Push the Pace’ in the National Institute for Health Research

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    Background Those running well-organised health research systems are likely to be alert for ways in which they might increase the quality of the services they provide and address any problems identified. This is important because the efficiency of the research system can have a major impact on how long it takes for new treatments to be developed and reach patients. This opinion piece reflects on the experience and learning of the United Kingdom-based National Institute for Health Research (NIHR) when it implemented continuous improvement activity to improve its processes. Discussion This paper describes the structure and work of the NIHR and why, despite is successes as a health research system and ongoing local continuous improvement, it believed in the value of an organisation-wide continuous improvement activity. It did this by implementing an approach called ‘Push the Pace’. Initially, the organisation focused on reducing the amount of time it took for research to transition from an early concept to evidence that changes lives. This scrutiny enabled the NIHR to realise further areas of improvement it could make – additional goals were increased transparency, process simplification, and improved customer and stakeholder experience. We discuss our experience of Push the Pace with reference to literature on continuous improvement. Conclusion Continuous improvement is a cycle, an activity that is done constantly and over time, rather than an act or linear activity (such as Push the Pace). We believe that the work of Push the Pace has initiated a strong commitment to a culture of continuous improvement in the NIHR. This is significant because culture change is widely recognised as immensely challenging, particularly in such a large and distributed organisation. However, our biggest challenge will be to enable all staff and stakeholders of the NIHR to participate in the continuous improvement cycle

    Biallelic P4HTM variants associated with HIDEA syndrome and mitochondrial respiratory chain complex I deficiency

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    We report a patient with profound congenital hypotonia, central hypoventilation, poor visual behaviour with retinal hypopigmentation, and significantly decreased mitochondrial respiratory chain complex I activity in muscle, who died at 7 months of age having made minimal developmental progress. Biallelic predicted truncating P4HTM variants were identified following trio whole-genome sequencing, consistent with a diagnosis of hypotonia, hypoventilation, intellectual disability, dysautonomia, epilepsy and eye abnormalities (HIDEA) syndrome. Very few patients with HIDEA syndrome have been reported previously and mitochondrial abnormalities were observed in three of four previous cases who had a muscle biopsy, suggesting the possibility that HIDEA syndrome represents a primary mitochondrial disorder. P4HTM encodes a transmembrane prolyl 4-hydroxylase with putative targets including hypoxia inducible factors, RNA polymerase II and activating transcription factor 4, which has been implicated in the integrated stress response observed in cell and animal models of mitochondrial disease, and may explain the mitochondrial dysfunction observed in HIDEA syndrome

    Editorial

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    ‘A new spring, and a new sound’, so begins a famous Dutch poem. Will the birds sing differently, as the poet wishes in the next line? BKI, now 178 years old—surely one of the longest-running journals of Southeast Asian studies in the world, and known around its original home, the KITLV (Royal Institute), as ‘the Old Dame’—starts 2022 with a remarkable new development. For this reason, the first issue of the year opens with an Editorial. After generations of sound and steady editing under the direction of two scholars, one in the role of Chief Editor and one as Managing Editor, from now on, BKI will be run by an expanded editorial team of seven scholars drawn both from the geographical region, Southeast Asia, and the disciplines in the humanities and social sciences that BKI is dedicated to examining..

    Hypocrea rufa/Trichoderma viride: a reassessment, and description of five closely related species with and without warted conidia

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    The type species of the genus Hypocrea (Hypocreaceae, Hypocreales, Ascomycota, Fungi), H. rufa, is re-defined and epitypified using a combination of phenotype (morphology of teleomorphs and anamorphs, and characteristics in culture) and phylogenetic analyses of the translation-elongation factor 1α gene. Its anamorph, T. viride, the type species of Trichoderma, is re-described and epitypified. Eidamia viridescens is combined as Trichoderma viridescens and is recognised as one of the most morphologically and phylogenetically similar relatives of T. viride. Its teleomorph is newly described as Hypocrea viridescens. Contrary to frequent citations of H. rufa and T. viride in the literature, this species is relatively rare. Although both T. viride and T. viridescens have a wide geographic distribution, their greatest genetic diversity appears to be in Europe and North America. Hypocrea vinosa is characterised and its anamorph, T. vinosum sp. nov., is described. Conidia of T. vinosum are subglobose and warted. The new species T. gamsii is proposed. It shares eidamia-like morphology of conidiophores with T. viridescens, but it has smooth, ellipsoidal conidia that have the longest L/W ratio that we have seen in Trichoderma. Trichoderma scalesiae, an endophyte of trunks of Scalesia pedunculata in the Galapagos Islands, is described as new. It only produces conidia on a low-nutrient agar to which filter paper has been added. Additional phylogenetically distinct clades are recognised and provisionally delimited from the species here described. Trichoderma neokoningii, a T. koningii-like species, is described from a collection made in Peru on a fruit of Theobroma cacao infected with Moniliophthora roreri
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