4,536 research outputs found

    Surface transfer doped diamond diodes with metal oxide passivation and field-plate

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    Surface transfer-doping, involving hydrogen terminated diamond surfaces, has been an effective method for producing diamond devices for some years but suffered from poor device longevity and reproducibility. The emergence of metal oxides as an encapsulant has begun to change this situation. Here, HfO2 encapsulated surface transfer doped diamond Schottky diodes with stable device characteristics have been demonstrated. Ideality factor and Schottky barrier heights of the devices did not vary considerably across extended periods of use (up to 39 days). The devices showed excellent blocking capabilities, demonstrating no catastrophic breakdown under the maximum field applied and only a slight increase in leakage current at the reverse bias and field strength of 200 V and 0.167 MV cm−1 , respectively. Indeed, a large rectification ratio of up to 108 and a very low leakage current of ≈10−9 A cm−1 were maintained at this reverse bias (200 V). Furthermore, multiple devices were compared across a single substrate, something rarely reported previously for surface transfer doped diamond diodes. Leakage currents and rectification ratios were similar for all of the devices. The authors are grateful to the UKs Engineering and Physical Sciences Research Council (EPSRC) and BAE Systems Marine Ltd. for the award of a “Cooperative Awards in Science and Engineering (CASE)” Ph.D. Studentship for R.J.W. and to EPSRC for the award of related research funding (No. EP/H020055/1). A.C.P.-T. and R.B.J. also acknowledge invaluable assistance, both financial and in the form of international collaborations, from the European Commission Horizon 2020 Project “GREENDIAMOND” (H2020 Large Project under Grant No. SEP-210184415). Lambda Photometrics Ltd. and Everbeing International Corporation are gratefully acknowledged for use of a Everbeing EB-6 DC probe station. Finally, the LCN Cleanroom is acknowledged for the invaluable assistance of technicians and for the use of the ALD, evaporation, and photo-lithography tools

    Combined Microscopy, Calorimetry and X-ray Scattering Study of Fluorinated Dimesogens

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    The material FDO11DFCB3 (compound 2 in this work) remains the only example of a liquid-crystalline material to exhibit a phase transition from the heliconical twist-bend phase into a lamellar smectic A mesophase, additionally this material exhibits a previously unidentified mesophase. We have prepared and characterised several homologues of this compound, with each material subjected to an in-depth analysis by optical microscopy, calorimetry and small angle X-ray scattering studies. Despite FDO11DFCB3 being similar in chemical structure to the novel materials presented herein its liquid-crystalline behaviour is rather different, indicating an unexpected sensitivity of the twist-bend phase to molecular structure

    Longer fixation duration while viewing face images

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    The spatio-temporal properties of saccadic eye movements can be influenced by the cognitive demand and the characteristics of the observed scene. Probably due to its crucial role in social communication, it is argued that face perception may involve different cognitive processes compared with non-face object or scene perception. In this study, we investigated whether and how face and natural scene images can influence the patterns of visuomotor activity. We recorded monkeys’ saccadic eye movements as they freely viewed monkey face and natural scene images. The face and natural scene images attracted similar number of fixations, but viewing of faces was accompanied by longer fixations compared with natural scenes. These longer fixations were dependent on the context of facial features. The duration of fixations directed at facial contours decreased when the face images were scrambled, and increased at the later stage of normal face viewing. The results suggest that face and natural scene images can generate different patterns of visuomotor activity. The extra fixation duration on faces may be correlated with the detailed analysis of facial features

    The Shapiro Design Lab Residency

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    A publication documenting the inaugural year of the Shapiro Design Lab Residency.https://deepblue.lib.umich.edu/bitstream/2027.42/142813/1/DesignLabResidency_Publication.pdfDescription of DesignLabResidency_Publication.pdf : PDF of publicatio

    Rehabilitation after paediatric acquired brain injury: Longitudinal change in content and effect on recovery

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    Data availability statement: Data availability limited due to privacy/ethical restrictions. Please approach authors.Supporting Information is available online at https://onlinelibrary.wiley.com/doi/10.1111/dmcn.15199#support-information-section .Copyright © 2022 The Authors. Aim: To describe cross-sectional and longitudinal variation in neurorehabilitation content provided to young people after severe paediatric acquired brain injury (pABI) and to relate this to observed functional recovery. Method: This was an observational study in a cohort of admissions to a residential neurorehabilitation centre. Recovery was described using the Pediatric Evaluation of Disability – Computer Adaptive Testing instrument. Rehabilitation content was measured using the recently described Paediatric Rehabilitation Ingredients Measure (PRISM) and examined using multidimensional scaling. Results: The PRISM reveals wide variation in rehabilitation content between and during admissions primarily reflecting proportions of child active practice, child emotional support, and other management of body structure and function. Rehabilitation content is predicted by pre-admission recovery, suggesting therapist decisions in designing rehabilitation programmes are shaped by their initial expectations of recovery. However, significant correlations persist between plausibly-related aspects of delivered therapy and observed post-admission recovery after adjusting for such effects. Interpretation: The PRISM approach to the analysis of rehabilitation content shows promise in that it demonstrates significant correlations between plausibly-related aspects of delivered therapy and observed recovery that have been hard to identify with other approaches. However, rigorous, causal analysis will be required to truly understand the contributions of rehabilitation to recovery after pABI

    Therapeutic Myeloperoxidase Inhibition Attenuates Neutrophil Activation, ANCA-Mediated Endothelial Damage, and Crescentic GN

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    BACKGROUND: Myeloperoxidase released after neutrophil and monocyte activation can generate reactive oxygen species, leading to host tissue damage. Extracellular glomerular myeloperoxidase deposition, seen in ANCA-associated vasculitis, may enhance crescentic GN through antigen-specific T and B cell activation. Myeloperoxidase-deficient animals have attenuated GN early on, but augmented T cell responses. We investigated the effect of myeloperoxidase inhibition, using the myeloperoxidase inhibitor AZM198, to understand its potential role in treating crescentic GN. METHODS: We evaluated renal biopsy samples from patients with various forms of crescentic GN for myeloperoxidase and neutrophils, measured serum myeloperoxidase concentration in patients with ANCA-associated vasculitis and controls, and assessed neutrophil extracellular trap formation, reactive oxygen species production, and neutrophil degranulation in ANCA-stimulated neutrophils in the absence and presence of AZM198. We also tested the effect of AZM198 on ANCA-stimulated neutrophil-mediated endothelial cell damage in vitro, as well as on crescentic GN severity and antigen-specific T cell reactivity in the murine model of nephrotoxic nephritis. RESULTS: All biopsy specimens with crescentic GN had extracellular glomerular myeloperoxidase deposition that correlated significantly with eGFR and crescent formation. In vitro, AZM198 led to a significant reduction in neutrophil extracellular trap formation, reactive oxygen species production, and released human neutrophil peptide levels, and attenuated neutrophil-mediated endothelial cell damage. In vivo, delayed AZM198 treatment significantly reduced proteinuria, glomerular thrombosis, serum creatinine, and glomerular macrophage infiltration, without increasing adaptive T cell responses. CONCLUSIONS: Myeloperoxidase inhibition reduced neutrophil degranulation and neutrophil-mediated endothelial cell damage in patients with ANCA-associated vasculitis. In preclinical crescentic GN, delayed myeloperoxidase inhibition suppressed kidney damage without augmenting adaptive immune responses, suggesting it might offer a novel adjunctive therapeutic approach in crescentic GN

    Initial fixation placement in face images is driven by top-down guidance

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    The eyes are often inspected first and for longer period during face exploration. To examine whether this saliency of the eye region at the early stage of face inspection is attributed to its local structure properties or to the knowledge of its essence in facial communication, in this study we investigated the pattern of eye movements produced by rhesus monkeys (Macaca mulatta) as they free viewed images of monkey faces. Eye positions were recorded accurately using implanted eye coils, while images of original faces, faces with scrambled eyes, and scrambled faces except for the eyes were presented on a computer screen. The eye region in the scrambled faces attracted the same proportion of viewing time and fixations as it did in the original faces, even the scrambled eyes attracted substantial proportion of viewing time and fixations. Furthermore, the monkeys often made the first saccade towards to the location of the eyes regardless of image content. Our results suggest that the initial fixation placement in faces is driven predominantly by ‘top-down’ or internal factors, such as the prior knowledge of the location of “eyes” within the context of a face

    Spin and Statistics and First Principles

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    It was shown in the early Seventies that, in Local Quantum Theory (that is the most general formulation of Quantum Field Theory, if we leave out only the unknown scenario of Quantum Gravity) the notion of Statistics can be grounded solely on the local observable quantities (without assuming neither the commutation relations nor even the existence of unobservable charged field operators); one finds that only the well known (para)statistics of Bose/Fermi type are allowed by the key principle of local commutativity of observables. In this frame it was possible to formulate and prove the Spin and Statistics Theorem purely on the basis of First Principles. In a subsequent stage it has been possible to prove the existence of a unique, canonical algebra of local field operators obeying ordinary Bose/Fermi commutation relations at spacelike separations. In this general guise the Spin - Statistics Theorem applies to Theories (on the four dimensional Minkowski space) where only massive particles with finite mass degeneracy can occur. Here we describe the underlying simple basic ideas, and briefly mention the subsequent generalisations; eventually we comment on the possible validity of the Spin - Statistics Theorem in presence of massless particles, or of violations of locality as expected in Quantum Gravity.Comment: Survey based on a talk given at the Meeting on "Theoretical and experimental aspects of the spin - statistics connection and related symmetries", Trieste, Italy - October 21-25, 200

    Gaggle on the Gavel: Designing an Interactive Website to Create a Community of Lawyers

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    Law is behind other industries and professions in its implementation of technolo-gy that could make the practice of law and the delivery of legal services more ef-fective and satisfying. Although there has been considerable development in le-gal technology over the past few years, research identified the need for an interac-tive LinkedIn-style online community for lawyers to communicate other lawyers. Such a community would be particularly beneficial for solo practitioners, lawyers in small firms and lawyers in rural communities and would also provide a con-venient way to connect with lawyers for referrals and recommendations, for spe-cialized expertise and to develop contacts in different geographic locations. Ten-tatively titled Gaggle on the Gavel is an attempt to create such a community that would gather a number of attractive features and functionality under one umbrella and be compliant with the rules of professional conduct with respect to client con-fidentiality, security, advertising and solicitation. A system has been designed, prototyped and revised based on feedback from a focus group of lawyers
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