941 research outputs found

    Test structures to characterise a novel circuit fabrication technique that uses offset lithography

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    This paper reports on the use of microelectronic test structures to characterise a novel fabrication technique for thin-film electronic circuit boards. In this technology, circuit tracks are formed on paper-like substrates by depositing films of a metal-loaded ink via a standard lithographic printing process. Sheet resistance and line width are electrically evaluated and these quantities are compared with optical and surface profiling measurements

    Radiocarbon dating and the Naqada relative chronology

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    The Naqada relative chronology provides the main cultural framework for the Predynastic period of ancient Egypt. It was devised in the late nineteenth century by Flinders Petrie to improve understanding of the prehistoric origins of the Egyptian state. Petrie's approach became widely known and formed the basis for the development of seriation. In this study, we test the reliability of the Naqada relative chronology as a dating tool against all the relevant radiocarbon information. The results show that the main blocks of the relative sequence do form a true chronology, but also indicate that the system is much less reliable at the level of individual phases. We discuss the nature of the discrepancies and the broader influence of the relative chronology on current understanding of Early Egypt

    Medical student‐led simulation in COVID‐19 crisis

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    Background: Simulation training is an effective tool for improving confidence in healthcare workers. During the recent COVID‐19 pandemic, large numbers of staff required re‐training to manage unfamiliar situations. We present a set of medical student‐led clinical simulation sessions and evaluate their effects on (i) confidence among redeployed healthcare workers managing COVID‐19 patients and (ii) medical students’ confidence as educators. / Methods: Half‐day simulation training sessions consisting of three COVID‐related clinical scenarios were devised by senior medical students and delivered to a group of approximately 150 healthcare workers over six repeated sessions prior to redeployment to COVID‐19 wards. We distributed an anonymous pre‐ and post‐simulation questionnaire to 36 participants in the final group exploring their experiences. The confidence scores were analysed using the Wilcoxon signed‐rank test. Following the delivery of teaching, medical students completed a questionnaire assessing their personal experiences of designing and delivering the exercises. / Results: Data are available for 35/36 participants approached. Respondents reported being significantly more confident after the training in all aspects of managing COVID‐19 patients, including triage, complex discharge, recognising deterioration, initiating basic life support, managing symptoms and advising on visiting policies (p < 0.001); 97% of respondents rated the training as useful. Thematic analysis of medical students’ responses demonstrated mutual benefit. / Discussion: This study demonstrates the strengths of simulation training in helping to build staff confidence in a rapidly evolving situation and highlights the value of medical students in supporting a hospital’s response to an outbreak. We recommend further studies of student‐led simulation exercises, including longer‐term follow‐up

    Diagnosing Spin at the LHC via Vector Boson Fusion

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    We propose a new technique for determining the spin of new massive particles that might be discovered at the Large Hadron Collider. The method relies on pair-production of the new particles in a kinematic regime where the vector boson fusion production mechanism is enhanced. For this regime, we show that the distribution of the leading jets as a function of their relative azimuthal angle can be used to distinguish spin-0 from spin-1/2 particles. We illustrate this effect by considering the particular cases of (i) strongly-interacting, stable particles and (ii) supersymmetric particles carrying color charge. We argue that this method should be applicable in a wide range of new physics scenarios.Comment: 5 pages, 4 figure

    Atom--Molecule Coherence in a Bose-Einstein Condensate

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    Coherent coupling between atoms and molecules in a Bose-Einstein condensate (BEC) has been observed. Oscillations between atomic and molecular states were excited by sudden changes in the magnetic field near a Feshbach resonance and persisted for many periods of the oscillation. The oscillation frequency was measured over a large range of magnetic fields and is in excellent quantitative agreement with the energy difference between the colliding atom threshold energy and the energy of the bound molecular state. This agreement indicates that we have created a quantum superposition of atoms and diatomic molecules, which are chemically different species.Comment: 7 pages, 6 figure

    Hepatitis viral markers in patients undergoing primary liver transplants

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    The purpose of the study was to determine the prevalence in liver transplant (OLTx) patients of the hepatitis markers (anti-A, anti-B, anti-C, anti-D and HBsAg) and the interrelationships between markers and patients' sexes, ages, dates of transplant, clinicopathological diagnoses, and short-term survivals. Slightly more than half of the patients were male. Anti-A and anti-B were about evenly distributed between male and female. Anti-C, anti-D, and HBsAg were far more common in males. Age and year of transplant showed only a moderate increase in anti-A with increasing age. Anti-A was found in 57% of all patients, anti-B in 18%, anti-C in 17%, and HBsAg in 17%. Anti-D was tested only in patients who were positive for anti-B or HBsAg and occurred in 21 (11%) of 185. The poorest short-term survival occurred in males who showed both anti-A and HBsAg. © 1993 Plenum Publishing Corporation

    Left to Their Own Devices: Breakdowns in United States Medical Device Premarket Review

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    Using examples from recent FDA regulatory proceedings, Jonas Hines and colleagues critique the medical device premarket review and identify eight weaknesses in the process that should be remedied
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