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residual Attention Deep SVDD for COVID-19 Diagnosis Using CT Scans

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Computers, Materials & Continua 2023年第2期74卷 3333-3350页

作者： Akram Ali Alhadad Omar Tarawneh reham r.Mostafa Hazem M.El-Bakry Information Systems Department Faculty of Computers and InformationMansoura UniversityMansoura35511Egypt Computer Science Department Ibb UniversityIbbYemen SE Department Faculty of Computer Sciences and InformaticsAmman Arab UniversityAmman11953Jordan

COVID-19 is the common name of the disease caused by the novel coronavirus(2019-nCoV)that appeared in Wuhan,China in *** the infected people is the most important factor in the fight against the *** gold-standard test to diagnose COVID-19 is polymerase chain reaction(PCr),but it takes 5–6 h and,in the early stages of infection,may produce false-negative *** Computed Tomography(CT)images to diagnose patients infected with COVID-19 has become an urgent *** this study,we propose a residual attention deep support vector data description SVDD(rADSVDD)approach to diagnose *** is a novel approach combining residual attention with deep support vector data description(DSVDD)to classify the CT *** the best of our knowledge,we are the first to combine residual attention with DSVDD in general,and specifically in the diagnosis of *** attention with DSVDD naively may cause model *** in the proposed rADSVDD guides the network during training and enables quick learning,residual connectivity prevents vanishing *** approach consists of three models,each model is devoted to recognizing one certain disease and classifying other diseases as *** models learn in an end-to-end *** proposed approach attained high performance in classifying CT images into intact,COVID-19,and non-COVID-19 *** evaluate the proposed approach,we created a dataset from published datasets and had it assessed by an experienced *** proposed approach achieved high performance,with the normal model attained sensitivity(0.96–0.98),specificity(0.97–0.99),F1-score(0.97–0.98),and area under the receiver operator curve(AUC)0.99;the COVID-19 model attained sensitivity(0.97–0.98),specificity(0.97–0.99),F1-score(0.97–0.99),and AUC 0.99;and the non-COVID pneumoniamodel attained sensitivity(0.97–1),specificity(0.98–0.99),F1-score(0.97–0.99),and AUC 0.99.

关键词： Deep learning deep SVDD residual attention anomaly detection COVID-19 Coronavirus

MHD stagnation-point flow and heat transfer towards stretching sheet with induced magnetic field

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Applied Mathematics and Mechanics(English Edition) 2011年第4期32卷 409-418页

作者： F.M.ALI r.NAZAr N.M.ArIFIN I.POP Department of Mathematics Institute of Mathematical ResearchUniversiti Putra Malaysia School of Mathematical Sciences Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia Faculty of Mathematics University of Cluj

The problem of the steady magnetohydrodynamic （MHD） stagnation-point flow of an incompressible viscous fluid over a stretching sheet is studied. The effect of an induced magnetic field is taken into account. The nonlinear partial differential equations are transformed into ordinary differential equations via the similarity transformation. The transformed boundary layer equations are solved numerically using the shooting method. Numerical results are obtained for various magnetic parameters and Prandtl numbers. The effects of the induced magnetic field on the skin friction coefficient, the local Nusselt number, the velocity, and the temperature profiles are presented graphically and discussed in detail.

关键词： boundary layer heat transfer induced magnetic field numerical solution magnetohydrodynamic (MHD) flow stretching sheet

Structural and micro structural studies of PbO-doped SnO_2 sensor for detection of methanol, propanol and acetone

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Journal of Natural Gas Chemistry 2011年第2期20卷 179-183页

作者： J. K. Srivastava Preeti Pandey V. N. Mishra r. Dwivedi Center for research in Microelectronics Department of Electronics Engineering Institute of Technology Banaras Hindu University

In the present work the structural information of PbO-doped SnO2 thick film sensor has been investigated with X-ray diffractometer （XrD） and scanning electron microscope （SEM）. Initially, SnO2 powder was derived using sol-gel process and was subsequently doped with PbO and ground up to nanosized particles. A suitable gas sensor structure was fabricated on 1′′×1′′ alumina substrate using thick film technology. The necessary paste for screen printing was also developed. SEM results showed sol-gel derived powder gets more agglomerated in the thick film form. The sensitivity of the sensor has been investigated at different temperatures （150 ？C？350 ？C） upon exposure to methanol, propanol and acetone, yielding a maximum at 250 ？C for acetone with 1 wt% PbO-doping while at 350 ？C for propanol with 3 wt% PbO-doping of the sensor. The reduction of particle size to nanometers （validated through XrD） leads to a dramatic improvement in sensitivity of sensors for the chosen organic vapors. The results also correlate well with the microstructural properties of the material and the dopant.

关键词： gas sensor nanosized SnO2 Sol-gel thick film

Amnion epithelial cells——a novel therapy for ischemic stroke?

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Neural regeneration research 2018年第8期13卷 1346-1349页

作者： Megan A.Evans Brad r.S.Broughton Grant r.Drummond Henry Ma Thanh G.Phan Euan M.Wallace rebecca Lim Christopher G.Sobey Department of Physiology Anatomy & Microbiology La Trobe University Cardiovascular Disease Program Department of Pharmacology Biomedicine Discovery Institute Monash University Department of Medicine Monash University The ritchie Centre Hudson Institute of Medical Research Department of Obstetrics and Gynaecology Monash University

Stroke is a leading cause of death and disability and new therapies are desperately needed. Given the complex nature of ischemic brain injury, it has been postulated that cell-based therapies may be useful. However, cell resources, invasive extraction procedures, immunological rejection, tumorigenesis and ethical challenges make it unlikely that many stem cell types could serve as a practical source for therapy. By contrast, these issues do not pertain to human amnion epithelial cells（h AECs）, which are placenta-derived stem cells. We recently assessed the effects of systemically delivered hAECs on stroke outcome using four animal models of stroke. We demonstrated that when injected intravenously after ischemia onset, hAECs migrate preferentially to the spleen and injured brain to limit apoptosis and inflammation, and attenuate early brain infiltration of immune cells, progression of infarction and systemic immunosuppression and to ultimately ameliorate functional deficits. When administration of hAECs is delayed by 1-3 days poststroke, long-term functional recovery can still be enhanced in young and aged mice of either sex. Moreover, our proof-of-principle findings suggest that h AECs are effective at limiting post-stroke infarct development in non-human primates. Overall, the results suggest that hAECs could be a viable clinical stroke therapy.

关键词： ischemic stroke cerebral infarction stem cells human amnion epithelial cells inflammation immunosuppression brain repair mouse non-human primate

Many-body Interatomic Potentials for Computer Simulation of Physical Processes in Metals and Alloys

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Journal of Materials Science & Technology 1998年第5期14卷 429-433页

作者： Kuznetsov, V.M. rudenskii, G.E. Kadyrov, r.I. Kaminskii, P. Institute of Strength Physics and Material Science Russian Academy of Sciences Siberian Branch Academicheskii av. 2/1 634048 Tomsk Russian Federation

A model of binding forces in metals and alloys, based on the density functional theory and accounted effects of the many-body interactions, was proposed. The developed method can be easily applied for study of metals and alloys by the molecular dynamics simulation. The potentials of interatomic interactions have been found by the proposed method and applied for calculations of equation of state, elastic moduli and phonon dispersion in metals Ni, Al, and alloys NiAl, Ni//3Al. results of the calculations are in good agreement with known experimental data both for pure metals and alloys. (Edited author abstract) 16 refs.

关键词： Nickel

Formation of rrr-a-tocopherol in rumen and intestinal digestibility of tocopherols in dairy cows

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Animal Nutrition 2023年第4期15卷 350-363页

作者： Saman Lashkari Farhad M.Panah Martin r.Weisbjerg Søren K.Jensen Department of Animal and Veterinary Sciences Aarhus UniversityDenmark

Tocopherol sources in diets are often a combination of all-rac-a-tocopheryl acetate(synthetic a-tocopherol)from vitamin supplements and natural tocopherols and 2r-(4’r,8’r)-5,7,8-trimethyltocotrienol(a-tocotrienols)from the feed *** a-tocopherol consists of 8 different stereoisomers including 2r-(4’r,8’r)-5,7,8-trimethyltocol(rrr-a-tocopherol),2r-(4’S,8’r)-5,7,8-trimethyltocol(rSr-a-tocopherol),2r-(4’r,8’S)-5,7,8-trimethyltocol(rrS-a-tocopherol),2r-(4’S,8’S)-5,7,8-trimethyltocol(rSS-a-tocopherol),2S-(4’S,8’S)-5,7,8-trimethyltocol(SSS-a-tocopherol),2S-(4’r,8’S)-5,7,8-trimethyltocol(SrS-a-tocopherol),2S-(4’S,8’r)-5,7,8-trimethyltocol(SSr-a-tocopherol),and2S-(4’r,8’r)-5,7,8-trimethyltocol(Srr-a-tocopherol).The pre-absorption metabolism of tocopherols and tocotrienols in ruminants differs from monogastric animals due to the extensive microbial fermentation in the anaerobic *** current study investigated the impact of toasting and decortication of oats on metabolism in the digestive tract(synthesis,digestion),and intestinal digestibility of tocopherols in dairy cows by using 4 ruminal and intestinal cannulated Danish Holstein cows in a 4×4 Latin square design for 4 *** were fed a total mixed ration ad libitum containing different forms of oats:whole oat,decorticated oat,toasted oat,and decorticated toasted oat,all rolled before mixed *** means across 4 treatments were statistically analyzed,testing whether overall means were different from *** or toasting did not affect the balance or digestibility of a-tocopherols in *** across treatments showed the ruminal degradation of synthetic a-tocopherol(279 mg/d,P=0.02;P-value shows that average across treatments is different from zero),synthetic 2r-a-tocopherol(133 mg/d,PrrS-,rSr-and rSS-a-tocopherol),and 2S-a-tocopherol(190 mg/d;PrS-,SSr,and Srr-a-tocopherol),while rrr-a-tocopherol was formed in the rumen(221 mg/d,P=0.1

关键词： Vitamin E a-Tocopherol stereoisomers Toasting Decortication Cow

Structural and photoluminescence studies on europium-doped lithium tetraborate(Eu:Li2B4O7)single crystal grown by microtube Czochralski(μT-Cz)technique

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Chinese Physics B 2016年第5期25卷 429-433页

作者： A Kumaresh r Arun Kumar N ravikumar U Madhusoodanan B S Panigrahi K Marimuthu M Anuradha GrD Centre for Materials research PSG College of TechnologyCoimbatoreIndia Department of Physics PSG College of TechnologyCoimbatoreIndia radiation Safety Division Indira Gandhi Centre for Atomic ResearchKalpakkamIndia Department of Physics Gandhigram Rural UniversityDindigulIndia PSG Institute of Advanced Studies CoimbatoreIndia

rare earth europium（Eu（3＋））-doped lithium tetraborate（Eu：Li_2B_4O_7） crystal is grown from its stoichiometric melt by microtube Czochralski pulling technique（μT-Cz） for the first time. The grown crystals are subjected to powder x-ray diffraction（PXrD） analysis which reveals the tetragonal crystal structure of the crystals. UV–vis–NIr spectral analysis is carried out to study the optical characteristics of the grown crystals. The crystal is transparent in the entire visible region, and the lower cutoff is observed to be at 304 nm. The existence of BO_3 and BO_4 bonding structure and the molecular associations are analyzed by Fourier transform infrared（FTIr） spectroscopy. The results of excitation and emission-photoluminescence spectra of europium ion incorporated in lithium tetraborate（LTB） single crystal reveal that the observations of peaks at 258,297, and 318 nm in the excitation spectra and peaks at 579, 591, 597, 613, and 651 nm are observed in the emission *** chromaticity coordinates are calculated from the emission spectra, and the emission intensity of the grown crystal is characterized through a CIE 1931（Commission International d＇Eclairage） color chromaticity diagram.

关键词： crystal growth optical material growth from melt photoluminescence study

Effect of aging treatment on irradiation-induced segregation of high Mn-Cr steel

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Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 58-61页

作者： D.S.BAE S.P.LEE Y.r.CHO H.TAKAHASHI Department of Advanced Materials Engineering Dong-Eui University Department of Materials Engineering Dong-Eui University Department of Materials Science and Engineering Pusan National University Center for Advanced research of Energy Conversion Materials Hokkaido University

To investigate the effect of aging treatment on irradiation-induced segregation of high Mn-Cr steel, specimens for electron-beam irradiation were prepared from the high Mn-Cr austenitic steel which was solution treated at 1 373 K for 1 h and aging treated at 573 K for 1 000 h, respectively. The electron-beam irradiation was performed at 573 K up to doses of 5.4 dpa in a 1 250 kV HVEM and irradiation-induced segregation analyses were carried out by an EDX in a 200 kV FE-TEM. The results show that void formation is not observed in both solution treated and aging treated ones. The amount of Cr segregation at the grain boundary decreases in the aged one; however, that of Mn is not changed in solution treated one.

关键词： high Mn-Cr steel HVEM electron-beam irradiation irradiation-induced segregation aging

Pd-gate MOS sensor for detection of methanol and propanol

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Journal of Natural Gas Chemistry 2011年第2期20卷 123-127页

作者： Preeti Pandey J. K. Srivastava V. N. Mishra r. Dwivedi Center for research in Microelectronics Department of Electronics Engineering Institute of Technology Banaras Hindu University

The present paper focused on the detection of methanol and propanol using Pd-gate metal-oxide-semiconductor （MOS） sensor. Surface mor- phology and composition of the gate film were studied by scanning electron microscopy （SEM） and atomic force microscopy （AFM）. The response of the sensor for propanol and methanol was measured as shift in capacitance-voltage （C-V） and conductance-voltage （G-V） curves of the MOS structure. The sensitivity of the sensor towards methanol was found to be greater than that towards propanol. It was 58.2% for methanol and 32% for propanol （at 0.6 V, 1 MHz） in terms of capacitance measurements, while in terms of conductance results the sensitivity was found to be 57.2% for methanol and 38.9% for propanol at 1 kHz. The discontinuities or cracks present in the microstructure of the gate material are believed to be mainly responsible for the high sensitivity of the sensor, going with the decomposition of gas molecules and subsequent hydrogen permeation through Pd.

关键词： MOS structure gas sensor palladium cracks sensitivity