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Protective effects of Balanites aegyptiaca extract, melatonin and ursodeoxycholic acid against hepatotoxicity induced by methotrexate in male rats

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Asian Pacific Journal of Tropical Medicine 2017年第6期10卷 627-634页

作者： Ayat Os Montasser Hanan saleh omar A.Ahmed-Farid Aida saad Mohamed-Assem s.Marie National Organization for Drug Control And Research Faculty of science Department of Zoology Cairo University

Objective: To compare the degree of ameliorative effects of Melatonin(MEL), Ursodeoxycholic acid(UDCA) and Balanites aegyptiaca(BA) against hepatotoxicity induced by MTX for one month. Methods: Eighty adult male rats(sprague Dawely) weighing(190±10g), were randomly divided into eight equal groups: Control, MTX, MEL, BA, UDCA, MTX+MEL, MTX+BA, MTX+UDCA. Liver function biomarker enzymes, liver tissue oxidative stress parameters, together with total antioxidant capacity and tumor necrosis factor(TNF-α) were determined. Histopathological and immunohistochemistry examinations for TNF-α were also done. Results: MTX showed significant increase in alanine transaminase(ALT), aspartate transaminase(AsT), alkaline phosphatase(ALP), gamma glutamyl transferase(GGT), total and direct bilirubin, as well as TNF-α levels, oxidized glutathione(GssG), malodialdehyde(MDA) and nitric oxide(NO). whereas, total protein, albumin, total antioxidant capacity, reduced glutathione(GsH), glutathione peroxidase(GPx), glutathione reductase(GR), glutathione s-transferase(GsT), superoxide dismutase(sOD) and catalase(CAT) levels were significantly decreased in MTX treated group. These alterations were improved by MEL and BA treatment, whereas no improvement was noticed in UDCA treatment. Conclusions: BA may be as promising as MEL in the hepatoprotection against MTX toxicity through their antioxidant and radical scavenging activities. In addition, it is not recommended to co-administer UDCA with MTX as it enhanced inflammation and damage to the liver.

关键词： Methotrexate Hepatotoxicity Melatonin Balanites aegyptiaca Ursodeoxycholic acid

Thermophysical properties of the Ni-based alloy Nimonic 80A up to 2400 K

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Rare Metals 2006年第5期25卷 529-531页

作者： B.Wilthan R.Tanzer W.schützenhfer G.Pottlacher Institute of Experimental Physics Graz University of TechnologyPetersgasse 168010 GrazAustria Bhler Edelstahl GmbH Mariazellerstrasse 258605 KapfenbergAustria

Nimonic 80A is a nickel-chromium alloy which is strengthened by additions of titanium and aluminium. The alloy is used for high temperature, high strength applications. Wire shaped Nimonic 80A samples are resistively volume heated as part of a fast capacitor discharge circuit. Time resolved measurements with sub-μs resolution of current through the specimen are performed with a Pearson probe, voltage drop across the specimen is measured with knife-edge contacts and ohmic voltage dividers and the radiance temperature of the sample with a pyrometer. These measurements allow to determine heat of fusion as well as heat capacity and electrical resistivity at initial geometry of Nimonic 80A as a function of temperature in the solid and in the liquid phase up to 2400 K.

关键词： thermophysical properties Nimonic 80A resistivity enthalpy heat capacity latent heat

Aspect-Oriented Modeling and Verification with Finite state Machines

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Journal of Computer science & Technology 2009年第5期24卷 949-961页

作者：徐殿祥 omar El-Ariss 许巍峰王林章 National Center for the Protection of the Financial Infrastructure Dakota State UniversityMadisonSD 57042 U.S.A. state Key Laboratory of Novel software Technology Department of Computer Science and TechnologyNanjing University Department of Computer science North Dakota State UniversityFargoND 58105 U.S.A Computer and Information science Department Gannon University109 University SquareEriePA 16541 U.S.A

Aspect-oriented programming modularizes crosscutting concerns into aspects with the advice invoked at the specified points of program execution. Aspects can be used in a harmful way that invalidates desired properties and even destroys the conceptual integrity of programs. To assure the quality of an aspect-oriented system, rigorous analysis and design of aspects are highly desirable. In this paper, we present an approach to aspect-oriented modeling and verification with finite state machines. Our approach provides explicit notations （e.g., pointcut, advice and aspect） for capturing crosscutting concerns and incremental modification requirements with respect to class state models. For verification purposes, we compose the aspect models and class models in an aspect-oriented model through a weaving mechanism. Then we transform the woven models and the class models not affected by the aspects into FsP （Finite state Processes）, which are to be checked by the LTsA （Labeled Transition system Analyzer） model checker against the desired system properties. We have applied our approach to the modeling and verification of three aspect-oriented systems. To further evaluate the effectiveness of verification, we created a large number of flawed aspect models and verified them against the system requirements. The results show that the verification has revealed all flawed models. This indicates that our approach is effective in quality assurance of aspect-oriented state models. As such, our approach can be used for model-checking state-based specification of aspect-oriented design and can uncover some system design problems before the system is implemented.

关键词： aspect-oriented modeling finite state machines modeling verification model checking

Big Data Analytics Using Graph signal Processing

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Computers, Materials & Continua 2023年第1期74卷 489-502页

作者： Farhan Amin omar M.Barukab Gyu sang Choi Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Korea Faculty of Computing and Information Technology-Rabigh King Abdulaziz UniversityJeddahSaudi Arabia

The networks are fundamental to our modern world and they appear throughout science and *** to a massive amount of data presents a unique opportunity to the researcher’s *** networks grow in size the complexity increases and our ability to analyze them using the current state of the art is at severe risk of failing to keep ***,this paper initiates a discussion on graph signal processing for large-scale data *** first provide a comprehensive overview of core ideas in Graph signal processing(GsP)and their connection to conventional digital signal processing(DsP).We then summarize recent developments in developing basic GsP tools,including methods for graph filtering or graph learning,graph signal,graph Fourier transform(GFT),spectrum,graph frequency,*** filtering is a basic task that allows for isolating the contribution of individual frequencies and therefore enables the removal of *** then consider a graph filter as a model that helps to extend the application of GsP methods to large *** show the suitability and the effeteness,we first created a noisy graph signal and then applied it to the *** several rounds of simulation *** see that the filtered signal appears to be smoother and is closer to the original noise-free distance-based *** using this example application,we thoroughly demonstrated that graph filtration is efficient for big data analytics.

关键词： Big data data science big data processing graph signal processing social networks

Accurate energy barriers for catalytic reaction pathways: an automatic training protocol for machine learning force fields

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npj Computational Materials 2023年第1期9卷 479-488页

作者： Lars L.schaaf Edvin Fako sandip De Ansgar schäfer Gábor Csányi Engineering Laboratory University of CambridgeCB21PZ CambridgeUK BAsF sE Carl-Bosch-Straße 3867056 LudwigshafenGermany

We introduce a training protocol for developing machine learning force fields(MLFFs),capable of accurately determining energy barriers in catalytic reaction *** protocol is validated on the extensively explored hydrogenation of carbon dioxide to methanol over indium *** the help of active learning,the final force field obtains energy barriers within 0.05 eV of Density Functional *** to the computational speedup,not only do we reduce the cost of routine in-silico catalytic tasks,but also find an alternative path for the previously established rate-limiting step,with a 40%reduction in activation ***,we illustrate the importance of finite temperature effects and compute free energy *** transferability of the protocol is demonstrated on the experimentally relevant,yet unexplored,top-layer reduced indium oxide *** ability of MLFFs to enhance our understanding of extensively studied catalysts underscores the need for fast and accurate alternatives to direct ab-initio simulations.

关键词： surface catalytic fields

Venous thromboembolism prophylaxis-prescribing patterns among elderly medical patients in a saudi tertiary care center:success or failure?

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Journal of Geriatric Cardiology 2020年第12期17卷 775-781页

作者： Dalal A.Alabdulkarim omar A.Almohammed Maha A.Al Ammari Nada s.Almaklafi Munirah A.Alkathiri Manal A.Aljohani Pharmaceutical Care service Ministry of the National Guard-Health AffairsRiyadhSaudi Arabia King Abdullah International Medical Research Center RiyadhSaudi Arabia Department of Clinical Pharmacy College of PharmacyKing Saud UniversityRiyadhSaudi Arabia

Background Hospitalized elderly patients are at high risk of venous thromboembolism(VTE),and the appropriate use of thromboprophylaxis can significantly reduce the incidence of VTE in high-risk *** investigated the pattern of VTE prophylaxis administration among elderly medical patients and assessed its appropriateness based on the American College of Chest Physicians(ACCP)*** A cross-sectional single-center study was conducted between October 2019 and March 2020,including hospitalized(>48 h),elderly(≥60 years),medical patients,and excluding patients receiving anticoagulant for other reason,having contraindication to thromboprophylaxis,or had VTE diagnosed within 48 *** Padua prediction score was used to determine the patients’risk for VTE,and thromboprophylaxis use was assessed against the ACCP *** The study included 396 patients with an average age of 75.0±9.01 years,and most patients(71.7%)were classified as high risk for VTE development(Padua score≥4 points).Thromboprophylaxis use was inappropriate in 27.3%of patients,of whom 85.2%were ineligible but still received *** who were classified as low risk of VTE were more likely to receive inappropriate thromboprophylaxis(AOR=76.5,95%CI:16.1-363.2),whereas patients with acute infection or rheumatologic disorder were less likely to receive inappropriate thromboprophylaxis(AOR=0.46,95%CI:0.22-0.96).Conclusions Although the use of thromboprophylaxis among high-risk elderly patients was reasonably adequate,a large proportion of low-risk patients were exposed to unnecessary risk through inappropriate overutilization of ***,healthcare providers should accurately assess patients’risk before prescribing thromboprophylaxis to ensure patient safety.

关键词： Hemorrhage Hospitalization Prophylaxis The elderly Venous thromboembolism

True grit: ingestion of small stone particles by hummingbirds in West Mexico

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Avian Research 2021年第4期12卷 739-749页

作者： omar Maya-García Mauricio Ortega-Flores Jorge E.schondube Posgrado en Ciencias Biológicas Unidad de PosgradoCoordinación del Posgrado en Ciencias BiológicasUniversidad Nacional Autónoma de MéxicoEdificio D1er pisoCircuito de PosgradosCiudad UniversitariaDel.CoyoacánC.P.04510 México D.F.Mexico Laboratorio de Ecología Funcional Instituto de Investigaciones en Ecosistemas y SustentabilidadUniversidad Nacional Autónoma de MéxicoAntigua Carretera a Pátzcuaro No.8701Col.Ex Hacienda de San Joséde la HuertaC.P.58190 MoreliaMichoacánMexico

Background: Grit is used by birds mainly for grinding hard food items but can also serve a nutritional role as a source of minerals. Ingestion of grit by birds has been documented primarily in species that feed on seeds and *** feeding mainly on nectar and small arthropods, hummingbirds also ingest grit, but why they do so is unclear. We quantified the number of grit particles in the stomachs of six species of hummingbirds during an annual cycle in a seasonal ecosystem of West ***: We compared the number of grit particles in the stomachs of different hummingbird species(Mexican Violetear Colibri thalassinus, Amethyst-throated Mountaingem Lampornis amethystinus, White-eared Hummingbird Basilinna leucotis, Rivoli's Hummingbird Eugenes fulgens, Broad-tailed Hummingbird selasphorus platycercus, and Rufous Hummingbird s. rufus), and between sex and age categories during the different seasons of a year. To deter-mine if grit was used to grind ingested arthropods, we examined the relationships between the number of grit parti-cles, the biomass of arthropods ingested, and their chitin ***: Although species did not differ in the number of grit particles in their stomachs, we found that grit was mostly ingested by female individuals, with only one male of one species(Mexican Violetear) presenting grit in its stomach. We also found that female hummingbirds had grit in their stomachs during the rainy and the cold-dry season(June-February) but not during the warm-dry season(March-May). Our analyses revealed no relationship between the number of grit particles and the amount of ingested arthropods and arthropod chitin content. However,high grit consumption was related to wasp ingestion on Mexican ***: Our results indicate that grit is used mainly by female hummingbirds. The seasonal variation in the ingestion of grit by female individuals suggests that it can be used to meet mineral requirements related to breed-ing;how

关键词： Arthropod chitin content Arthropod digestion Breeding season Mineral nutritional requirements

Mixed phase sodium manganese oxide as cathode for enhanced aqueous zinc-ion storage

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Chinese Journal of Chemical Engineering 2020年第8期28卷 2214-2220页

作者： Xinyu Wang Xinghua Qin Qiongqiong Lu Mingming Han Ahmad omar Daria Mikhailova Institute of Materials and Technology Dalian Maritime UniversityDalian 116026China Leibniz Institute for solid state and Materials Research(IFW)Dresden e.V. Helmholtzstraße 2001069 DresdenGermany school of Materials science and Engineering Central South UniversityChangsha 410083China

Aqueous zinc-ion batteries have been regarded as a promising alternative to large-scale energy storage, due to associated low-cost, improved safety and environmental friendliness. However, a high-performance cathode material for both rate capability and specific capacity is still a challenge. One kind of the more promising candidates are sodium manganese oxide(NMO) materials, although they suffer from individual issues and need to be further improved. Herein, we present a novel mixed phase NMO material composed of nearly equal amounts of Na(0.55)Mn2O4 and Na(0.7)MnO(2.05). The structured configuration with particle size of 200–500 nm is found to be beneficial towards improving the ion diffusion rate during the charge/discharge process. Compared with Na(0.7)MnO(2.05) and Na(0.55)Mn2O4, the mixed phase NMO demonstrates an enhanced rate capability and excellent long-term cycling stability with a capacity retention of 83% after 800 cycles. More importantly, the system also delivers an impressive energy density and power density, as 378 W·h·kg^-1 at 68.7 W·kg^-1, or 172 W·h·kg^-1 at 1705 W·kg^-1. The superior electrochemical performance is ascribed to the fast Zn^2+ diffusion rate because of a large ratio of capacitive contribution(63.9% at 0.9 m V·s^-1). Thus, the mixed phase route provides a novel strategy to enhance electrochemical performance, enabling mixed phase NMO as very promising material towards large-scale energy-storage applications.

关键词： Aqueous zinc-ion battery sodium manganese oxide Mixed phase High energy density

Geochemical characteristics of natural gases and source rocks in Obayied sub-basin,north Western Desert,Egypt:implications for gas-source correlation

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Acta Geochimica 2023年第2期42卷 241-255页

作者： Mostafa Hassan Mahmoud Leila Mohammed Ahmed Ghalib Issa omar Hegab Geology Department Faculty of ScienceMansoura UniversityMansoura 35516Egypt Egyptian General Petroleum Corporation CairoEgypt

Western Desert represents a major oil and gas province in Egypt producing more than 50%of the country’s oil *** and gas blend occurs in most producing fields,however,the genetic link between gas and liquid hydrocarbon phases are not *** sub-basin in the Western Desert where oil and gas phases coexist in the Middle Jurassic sandstones of the Khatatba Formation provides an ideal place to investigate the link between oil and gas *** analyses on rock samples(Rock–Eval pyrolysis,vitrinite reflectance,R_(o))and gases(molecular and isotopic composition)were conducted in order to identify the genetic characteristics of the hydrocarbon phases ***-relevant parameters(Rock–Eval T_(max),vitrinite reflectance R_(o))elucidate that only Middle Jurassic Khatatba organofacies capable of generating wet and dry hydrocarbon ***,the enrichment of C_(7)normal alkanes,mono-branched alkanes relative to polybranched components in the Obayied gases reflect their generation via cracking of *** modelling results confirm gas generation through both primary and secondary ***,secondary cracking of liquid hydrocarbon phases is volumetrically more *** cracking of the Khatatba organofacies likely predate and catalyze the secondary cracking of the liquid phases and therefore the volume of generated gas increases incrementally eastward where both processes *** present study highlights the significant role of secondary cracking in the generation and accumulation of huge gas accumulations in the basins containing oil-prone source intervals.

关键词： Primary and secondary cracking Gas geochemistry Jurassic Khatatba Obayied Western Desert