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Performance analysis of least square error [omega] filter for image reconstruction from projection
The Jabal Qarah Caves of The Hofuf Area, Northeastern Saudi Arabia: A Geological Investigation
The Jabal Al Qarah Caves, located approximately 13 km east of Al Hofuf, Eastern Province of Saudi Arabia, are an intricate cave system developed in the calcareous sandstone, marl and clay of the Upper Miocene to Lower Pliocene Hofuf Formation. Physiographically, the hill of Jabal Al Qarah is an outlier mesa that is located at the eastern edge of the Shedgum Plateau, the southern extension of the As Summan Plateau, and the larger Syrian Plateau to the north. Based on cave morphology and interpreted evolutionary histoty, the Jabal Al Qarah caves appear to be significantly different from other limestone caves reported in the As Summan Plateau. Jabal Al Qarah is known for its tall, linear cave passages and narrow canyons. The boxwork of linear passages is better developed here than any other known cave locations in the Eastern Province. Field observations, including orientations of the escarpment face of the Shedgum Plateau, joints, and fractures, coupled with a review of the tectonic history of the region, suggest that these caves resulted from erosional enlargement of a series of very deep and narrow joint-controlled fissure in the Hofuf Formation. Petrographic data, especially an abundance of well-preserved palygorskite type clay minerals, suggests that the Hofuf Formation was deposited in a mudflat-dominated coastal plain environment
Recent Progress in Extending the Cycle-Life of Secondary Zn-Air Batteries
Secondary Zn-air batteries with stable voltage and long cycle-life are of immediate interest to meet global energy storage needs at various scales. Although primary Zn-air batteries have been widely used since the early 1930s, large-scale development of electrically rechargeable variants has not been fully realized due to their short cycle-life. In this work, we review some of the most recent and effective strategies to extend the cycle-life of Zn-air batteries. Firstly, diverse degradation routes in Zn-air batteries will be discussed, linking commonly observed failure modes with the possible mechanisms and root causes. Next, we evaluate the most recent and effective strategies aimed at tackling individual or multiple of these degradation routes. Both aspects of cell architecture design and materials engineering of the electrodes and the electrolytes will be thoroughly covered. Finally, we offer our perspective on how the cycle-life of Zn-air batteries can be extended with concerted and tailored research directions to pave the way for their use as the most promising secondary battery system of the future
Investigation of new modification strategies for PVA membranes to improve their dehydration properties by pervaporation
International audienceNovel supported membranes based on polyvinyl alcohol (PVA) were developed using two strategies: first, by the modification of the PVA network, via so-called bulk modification, with the formation of the selective layer accomplished through the introduction of fullerenol and/or poly(allylamine hydrochloride), and second, by the functionalization of the surface with successive depositions of multilayered films of polyelectrolytes, such as poly(allylamine hydrochloride) and poly(sodium 4-styrenesulfonate) on the PVA surface. The membrane surface modifications were characterized by scanning electron microscopy and contact angle measurements. The modified PVA membranes were examined for their dehydration transport properties by the perva-poration of isopropyl alcohol-water (80/20% w/w), which was chosen as a model mixture. Compared with the pristine PVA membrane, the main improvement was a marked increase in permeance. It was found that the surface modifications mainly gave rise to a higher global flux but with a strong reduction in selectivity. Only the combination of both bulk and surface modifications with PEL could significantly increase the flux with a high water content in the permeate (over 98%). Lastly, it should be noted that this study developed a green procedure to prepare innovative membrane layers for dehydration, making use of only water as a working medium
Multi-shot Echo Planar Imaging for accelerated Cartesian MR Fingerprinting: An alternative to conventional spiral MR Fingerprinting.
PURPOSE: To develop an accelerated Cartesian MRF implementation using a multi-shot EPI sequence for rapid simultaneous quantification of T1 and T2 parameters. METHODS: The proposed Cartesian MRF method involved the acquisition of highly subsampled MR images using a 16-shot EPI readout. A linearly varying flip angle train was used for rapid, simultaneous T1 and T2 quantification. The results were compared to a conventional spiral MRF implementation. The acquisition time per slice was 8s and this method was validated on two different phantoms and three healthy volunteer brains in vivo. RESULTS: Joint T1 and T2 estimations using the 16-shot EPI readout are in good agreement with the spiral implementation using the same acquisition parameters (<4% deviation for T1 and <6% deviation for T2). The T1 and T2 values also agree with the conventional values previously reported in the literature. The visual qualities of fine brain structures in the multi-parametric maps generated by multi-shot EPI-MRF and Spiral-MRF implementations were comparable. CONCLUSION: The multi-shot EPI-MRF method generated accurate quantitative multi-parametric maps similar to conventional Spiral-MRF. This multi-shot approach achieved considerable k-space subsampling and comparatively short TRs in a similar manner to spirals and therefore provides an alternative for performing MRF using an accelerated Cartesian readout; thereby increasing the potential usability of MRF.The research leading to these results has received funding from the European Commission H2020 Framework Programme (H2020- MSCAITN- 2014), number 642685 MacSeNet, the Engineering and Physical Sciences Research Council (EPSRC) platform Compressed Quantitative MRI grant, number EP/M019802/1 and the Scottish Research Partnership in Engineering (SRPe) award, number SRPe PECRE1718/ 17
Project AIM: Autism Intervention Meta-Analysis for Studies of Young Children
Article is forthcoming as of December 2019. Citation for published version will be added once released by the American Psychological Association.In this comprehensive systematic review and meta-analysis of group design studies of
nonpharmacological early interventions designed for young children with autism spectrum
disorder (ASD), we report summary effects across seven early intervention types (behavioral,
developmental, naturalistic developmental behavioral intervention [NDBI], TEACCH,
sensory-based, animal-assisted, and technology-based), and 15 outcome categories indexing core
and related ASD symptoms. A total of 1,615 effect sizes were gathered from 130 independent
participant samples. A total of 6,240 participants, who ranged in age from 0-8 years, are
represented across the studies. We synthesized effects within intervention and outcome type
using a robust variance estimation approach to account for the nesting of effect sizes within
studies. We also tracked study quality indicators, and report an additional set of summary effect
sizes that restrict included studies to those meeting pre-specified quality indicators. Finally, we
conducted moderator analyses to evaluate whether summary effects across intervention types
were larger for proximal as compared to distal effects, and for context-bound as compared to
generalized effects. We found that when study quality indicators were not taken into account,
significant positive effects were found for behavioral, developmental, and NDBI intervention
types. When effect size estimation was limited to studies with randomized controlled trial (RCT)
designs, evidence of positive summary effects existed only for developmental and NDBI
intervention types. This was also the case when outcomes measured by parent report were
excluded. Finally, when effect estimation was limited to RCT designs and to outcomes for which
there was no risk of detection bias, no intervention types showed significant effects on any
outcome.Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) of the National Institutes of Health (U54HD083211; PI: Neul)Special Educatio
Morphine-induced hallucinations - resolution with switching to oxycodone: a case report and review of the literature
Palliation of pain with morphine in cancer patients can be complicated by adverse effects. Tolerance to these effects such as nausea and drowsiness usually occurs within a few days allowing continuation of morphine therapy. However, some patients may develop intolerable adverse effects even after several months on morphine when the dose is increased. A case of morphine-induced hallucinations in a cancer patient who had been on a subcutaneous infusion of diamorphine for several months is discussed. A switch to oxycodone resolved his hallucinations and gave him a new lease of life. The theories behind and evidence for opioid-switching is discussed along with strategies for dealing with intolerable opioid-induced adverse effects
Light Hadron Masses from Lattice QCD
This article reviews lattice QCD results for the light hadron spectrum. We
give an overview of different formulations of lattice QCD, with discussions on
the fermion doubling problem and improvement programs. We summarize recent
developments in algorithms and analysis techniques, that render calculations
with light, dynamical quarks feasible on present day computer resources.
Finally, we summarize spectrum results for ground state hadrons and resonances
using various actions.Comment: 53 pages, 24 figures, one table; Rev.Mod.Phys. (published version);
v2: corrected typ
Can AI help in screening Viral and COVID-19 pneumonia?
Coronavirus disease (COVID-19) is a pandemic disease, which has already
caused thousands of causalities and infected several millions of people
worldwide. Any technological tool enabling rapid screening of the COVID-19
infection with high accuracy can be crucially helpful to healthcare
professionals. The main clinical tool currently in use for the diagnosis of
COVID-19 is the Reverse transcription polymerase chain reaction (RT-PCR), which
is expensive, less-sensitive and requires specialized medical personnel. X-ray
imaging is an easily accessible tool that can be an excellent alternative in
the COVID-19 diagnosis. This research was taken to investigate the utility of
artificial intelligence (AI) in the rapid and accurate detection of COVID-19
from chest X-ray images. The aim of this paper is to propose a robust technique
for automatic detection of COVID-19 pneumonia from digital chest X-ray images
applying pre-trained deep-learning algorithms while maximizing the detection
accuracy. A public database was created by the authors combining several public
databases and also by collecting images from recently published articles. The
database contains a mixture of 423 COVID-19, 1485 viral pneumonia, and 1579
normal chest X-ray images. Transfer learning technique was used with the help
of image augmentation to train and validate several pre-trained deep
Convolutional Neural Networks (CNNs). The networks were trained to classify two
different schemes: i) normal and COVID-19 pneumonia; ii) normal, viral and
COVID-19 pneumonia with and without image augmentation. The classification
accuracy, precision, sensitivity, and specificity for both the schemes were
99.7%, 99.7%, 99.7% and 99.55% and 97.9%, 97.95%, 97.9%, and 98.8%,
respectively.Comment: 12 pages, 9 Figure
Scalar mesons moving in a finite volume and the role of partial wave mixing
Phase shifts and resonance parameters can be obtained from finite-volume
lattice spectra for interacting pairs of particles, moving with nonzero total
momentum. We present a simple derivation of the method that is subsequently
applied to obtain the pi pi and pi K phase shifts in the sectors with total
isospin I=0 and I=1/2, respectively. Considering different total momenta, one
obtains extra data points for a given volume that allow for a very efficient
extraction of the resonance parameters in the infinite-volume limit.
Corrections due to the mixing of partial waves are provided. We expect that our
results will help to optimize the strategies in lattice simulations, which aim
at an accurate determination of the scattering and resonance properties.Comment: 19 pages, 12 figure
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