776 research outputs found
Muller C-element based Decoder (MCD): A Decoder Against Transient Faults
This work extends the analysis and application of a digital error correction method called Muller C-element Decoding (MCD), which has been proposed for fault masking in logic circuits comprised of unreliable elements. The proposed technique employs cascaded Muller C-elements and XOR gates to achieve efficient error-correction in the presence of internal upsets. The error-correction analysis of MCD architecture and the investigation of C-elementâs robustness are first introduced. We demonstrate that the MCD is able to produce error-correction benefit in a high error-rate of internal faults. Significantly, for a (3,6) short-length LDPC code, when the decoding process is internally error-free the MCD achieves also a gain in terms of decoding performance by comparison to the well-known Gallager Bit-Flipping method. We further consider application of MCD to a general-purpose fault-tolerant model, coded Dual Modular Redundancy (cDMR), which offers low-redundancy error-resilience for contemporary logic systems as well as future nanoeletronic architectures
Safety and efficacy of etomidate and propofol anesthesia in elderly patients undergoing gastroscopy: A double-blind randomized clinical study
The aim of the present study is to compare the safety, efficacy and cost effectiveness of anesthetic regimens by compound, using etomidate and propofol in elderly patients undergoing gastroscopy. A total of 200 volunteers (65â79 years of age) scheduled for gastroscopy under anesthesia were randomly divided into the following groups: P, propofol (1.5â2.0 mg/kg); E, etomidate (0.15-0.2 mg/kg); P+E, propofol (0.75â1 mg/kg) followed by etomidate (0.075-0.1 mg/kg); and E+P, etomidate (0.075-0.01 mg/kg) followed by propofol (0.75â1 mg/kg). Vital signs and bispectral index were monitored at different time points. Complications, induction and examination time, anesthesia duration, and recovery and discharge time were recorded. At the end of the procedure, the satisfaction of patients, endoscopists and the anesthetist were evaluated. The recovery (6.1±1.2 h) and discharge times (24.8±2.8 h) in group E were significantly longer compared with groups P, P+E and E+P (P<0.05). The occurrence of injection pain in group P+E was significantly higher compared with the other three groups (P<0.05). In addition, the incidence of myoclonus and post-operative nausea and vomiting were significantly higher in group P+E compared with the other three groups (P<0.05). There was no statistical difference among the four groups with regards to the patients' immediate, post-procedure satisfaction (P>0.05). Furthermore, there was no difference in the satisfaction of anesthesia, as evaluated by the anesthetist and endoscopist, among the four groups (P>0.05). The present study demonstrates that anesthesia for gastroscopy in elderly patients can be safely and effectively accomplished using a drug regimen that combines propofol with etomidate. The combined use of propofol and etomidate has unique characteristics which improve hemodynamic stability, cause minimal respiratory depression and less side effects, provide rapid return to full activity and result in high levels of satisfaction
High performance waveguide uni-travelling carrier photodiode grown by solid source molecular beam epitaxy
The first waveguide coupled phosphide-based UTC photodiodes grown by Solid
Source Molecular Beam Epitaxy (SSMBE) are reported in this paper. Metal Organic
Vapour Phase Epitaxy (MOVPE) and Gas Source MBE (GSMBE) have long been the
predominant growth techniques for the production of high quality InGaAsP
materials. The use of SSMBE overcomes the major issue associated with the
unintentional diffusion of zinc in MOVPE and gives the benefit of the superior
control provided by MBE growth techniques without the costs and the risks of
handling toxic gases of GSMBE. The UTC epitaxial structure contains a 300 nm
n-InP collection layer and a 300 nm n++-InGaAsP waveguide layer. UTC-PDs
integrated with Coplanar Waveguides (CPW) exhibit 3 dB bandwidth greater than
65 GHz and output RF power of 1.1 dBm at 100 GHz. We also demonstrate accurate
prediction of the absolute level of power radiated by our antenna integrated
UTCs, between 200 GHz and 260 GHz, using 3d full-wave modelling and taking the
UTC-to-antenna impedance match into account. Further, we present the first
optical 3d full-wave modelling of waveguide UTCs, which provides a detailed
insight into the coupling between a lensed optical fibre and the UTC chip.Comment: 19 pages, 24 figure
From Laser Speckle to Particle Size Distribution in drying powders: A Physics-Enhanced AutoCorrelation-based Estimator (PEACE)
Extracting quantitative information about highly scattering surfaces from an
imaging system is challenging because the phase of the scattered light
undergoes multiple folds upon propagation, resulting in complex speckle
patterns. One specific application is the drying of wet powders in the
pharmaceutical industry, where quantifying the particle size distribution (PSD)
is of particular interest. A non-invasive and real-time monitoring probe in the
drying process is required, but there is no suitable candidate for this
purpose. In this report, we develop a theoretical relationship from the PSD to
the speckle image and describe a physics-enhanced autocorrelation-based
estimator (PEACE) machine learning algorithm for speckle analysis to measure
the PSD of a powder surface. This method solves both the forward and inverse
problems together and enjoys increased interpretability, since the machine
learning approximator is regularized by the physical law
N-WASP Is Required for Structural Integrity of the Blood-Testis Barrier
During spermatogenesis, the blood-testis barrier (BTB) segregates the adluminal (apical) and basal compartments in the seminiferous epithelium, thereby creating a privileged adluminal environment that allows post-meiotic spermatid development to proceed without interference of the host immune system. A key feature of the BTB is its continuous remodeling within the Sertoli cells, the major somatic component of the seminiferous epithelium. This remodeling is necessary to allow the transport of germ cells towards the seminiferous tubule interior, while maintaining intact barrier properties. Here we demonstrate that the actin nucleation promoting factor Neuronal Wiskott-Aldrich Syndrome Protein (N-WASP) provides an essential function necessary for BTB restructuring, and for maintaining spermatogenesis. Our data suggests that the N-WASP-Arp2/3 actin polymerization machinery generates branched-actin arrays at an advanced stage of BTB remodeling. These arrays are proposed to mediate the restructuring process through endocytic recycling of BTB components. Disruption of N-WASP in Sertoli cells results in major structural abnormalities to the BTB, including mis-localization of critical junctional and cytoskeletal elements, and leads to disruption of barrier function. These impairments result in a complete arrest of spermatogenesis, underscoring the critical involvement of the somatic compartment of the seminiferous tubules in germ cell maturation
Divergences in Real-Time Classical Field Theories at Non-Zero Temperature
The classical approximation provides a non-perturbative approach to
time-dependent problems in finite temperature field theory. We study the
divergences in hot classical field theory perturbatively. At one-loop, we show
that the linear divergences are completely determined by the classical
equivalent of the hard thermal loops in hot quantum field theories, and that
logarithmic divergences are absent. To deal with higher-loop diagrams, we
present a general argument that the superficial degree of divergence of
classical vertex functions decreases by one with each additional loop: one-loop
contributions are superficially linearly divergent, two-loop contributions are
superficially logarithmically divergent, and three- and higher-loop
contributions are superficially finite. We verify this for two-loop SU(N)
self-energy diagrams in Feynman and Coulomb gauges. We argue that hot,
classical scalar field theory may be completely renormalized by local (mass)
counterterms, and discuss renormalization of SU(N) gauge theories.Comment: 31 pages with 7 eps figure
Effectiveness and cost-effectiveness of a physical activity loyalty scheme for behaviour change maintenance: a cluster randomised controlled trial
Abstract
Background
Increasing physical activity in the workplace can provide employee physical and mental health benefits, and employer economic benefits through reduced absenteeism and increased productivity. The workplace is an opportune setting to encourage habitual activity. However, there is limited evidence on effective behaviour change interventions that lead to maintained physical activity. This study aims to address this gap and help build the necessary evidence base for effective, and cost-effective, workplace interventions.
Methods/design
This cluster randomised control trial will recruit 776 office-based employees from public sector organisations in Belfast and Lisburn city centres, Northern Ireland. Participants will be randomly allocated by cluster to either the Intervention Group or Control Group (waiting list control). The 6-month intervention consists of rewards (retail vouchers, based on similar principles to high street loyalty cards), feedback and other evidence-based behaviour change techniques. Sensors situated in the vicinity of participating workplaces will promote and monitor minutes of physical activity undertaken by participants. Both groups will complete all outcome measures. The primary outcome is steps per day recorded using a pedometer (Yamax Digiwalker CW-701) for 7 consecutive days at baseline, 6, 12 and 18Â months. Secondary outcomes include health, mental wellbeing, quality of life, work absenteeism and presenteeism, and use of healthcare resources. Process measures will assess intervention âdoseâ, website usage, and intervention fidelity. An economic evaluation will be conducted from the National Health Service, employer and retailer perspective using both a cost-utility and cost-effectiveness framework. The inclusion of a discrete choice experiment will further generate values for a cost-benefit analysis. Participant focus groups will explore who the intervention worked for and why, and interviews with retailers will elucidate their views on the sustainability of a public health focused loyalty card scheme.
Discussion
The study is designed to maximise the potential for roll-out in similar settings, by engaging the public sector and business community in designing and delivering the intervention. We have developed a sustainable business model using a âpointsâ based loyalty platform, whereby local businesses âsponsorâ the incentive (retail vouchers) in return for increased footfall to their business.
Trial registration
ISRCTN17975376
(Registered 19/09/2014)
Longitudinal Changes in the Motor Learning- Related Brain Activation Response in Presymptomatic Huntington\u27s Disease
Neurocognitive decline, including deficits in motor learning, occurs in the presymptomatic phase of Huntingtonâs disease (HD) and precedes the onset of motor symptoms. Findings from recent neuroimaging studies have linked these deficits to alterations in fronto-striatal and fronto-parietal brain networks. However, little is known about the temporal dynamics of these networks when subjects approach phenoconversion. Here, 10 subjects with presymptomatic HD were scanned with 15O-labeled water at baseline and again 1.5 years later while performing a motor sequence learning task and a kinematically matched control task. Spatial covariance analysis was utilized to characterize patterns of change in learningrelated neural activation occurring over time in these individuals. Pattern expression was compared to corresponding values in 10 age-matched healthy control subjects. Spatial covariance analysis revealed significant longitudinal changes in the expression of a specific learning-related activation pattern characterized by increasing activity in the right orbitofrontal cortex, with concurrent reductions in the right medial prefrontal and posterior cingulate regions, the left insula, left precuneus, and left cerebellum. Changes in the expression of this pattern over time correlated with baseline measurements of disease burden and learning performance. The network changes were accompanied by modest improvement in learning performance that took place concurrently in the gene carriers. The presence of increased network activity in the setting of stable task performance is consistent with a discrete compensatory mechanism. The findings suggest that this effect is most pronounced in the late presymptomatic phase of HD, as subjects approach clinical onset
The Monocular Depth Estimation Challenge
This paper summarizes the results of the first Monocular Depth Estimation
Challenge (MDEC) organized at WACV2023. This challenge evaluated the progress
of self-supervised monocular depth estimation on the challenging SYNS-Patches
dataset. The challenge was organized on CodaLab and received submissions from 4
valid teams. Participants were provided a devkit containing updated reference
implementations for 16 State-of-the-Art algorithms and 4 novel techniques. The
threshold for acceptance for novel techniques was to outperform every one of
the 16 SotA baselines. All participants outperformed the baseline in
traditional metrics such as MAE or AbsRel. However, pointcloud reconstruction
metrics were challenging to improve upon. We found predictions were
characterized by interpolation artefacts at object boundaries and errors in
relative object positioning. We hope this challenge is a valuable contribution
to the community and encourage authors to participate in future editions.Comment: WACV-Workshops 202
Anomalous excitonic phase diagram in band-gap-tuned Ta2Ni(Se,S)5
During a band-gap-tuned semimetal-to-semiconductor transition, Coulomb
attraction between electrons and holes can cause spontaneously formed excitons
near the zero-band-gap point, or the Lifshitz transition point. This has become
an important route to realize bulk excitonic insulators -- an insulating ground
state distinct from single-particle band insulators. How this route manifests
from weak to strong coupling is not clear. In this work, using angle-resolved
photoemission spectroscopy (ARPES) and high-resolution synchrotron x-ray
diffraction (XRD), we investigate the broken symmetry state across the
semimetal-to-semiconductor transition in a leading bulk excitonic insulator
candidate system Ta2Ni(Se,S)5. A broken symmetry phase is found to be
continuously suppressed from the semimetal side to the semiconductor side,
contradicting the anticipated maximal excitonic instability around the Lifshitz
transition. Bolstered by first-principles and model calculations, we find
strong interband electron-phonon coupling to play a crucial role in the
enhanced symmetry breaking on the semimetal side of the phase diagram. Our
results not only provide insight into the longstanding debate of the nature of
intertwined orders in Ta2NiSe5, but also establish a basis for exploring
band-gap-tuned structural and electronic instabilities in strongly coupled
systems.Comment: 27 pages, 4 + 9 figure
- âŠ