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Accuracy of urea breath test in Helicobacter pylori infection: Meta-analysis

World Journal of Gastroenterology 2015年第4期21卷 1305-1314页

作者： Mazen Ferwana Imad Abdulmajeed Ali Alhajiahmed Wedad Madani Belal Firwana Rim Hasan osama altayar Paul J Limburg Mohammad Hassan Murad Bandar Knawy National and Gulf Center for Evidence-Based Health Practice King Saud Bin Abdulaziz University for Health SciencesRiyadh 11426Saudi Arabia Department of Medicine University of Missouri ColumbiaMissouriMO 65211United States Knowledge and Evaluation Research Unit Mayo ClinicRochesterMN 65212United States Knowledge and Evaluation Research Unit Mayo ClinicRochesterMN 55905United States Department of Internal Medicine Allegheny General HospitalPittsburgPA 55905United States Division of Gastroenterology Mayo ClinicRochesterMN 55905United States Division of Preventive Medicine Mayo ClinicRochesterMN 55905United States

AIM: To quantitatively summarize and appraise the available evidence of urea breath test(UBT) use to diagnose Helicobacter pylori(H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy ***: We searched MEDLINE, EMBASE, Cochrane library and other databases for studies addressing the value of UBT in the diagnosis of H. pylori infection. We included cross-sectional studies that evaluated the diagnostic accuracy of UBT in adult patients with dyspeptic symptoms. Risk of bias was assessed using QUADAS(Quality Assessment of Diagnostic Accuracy Studies)-2 tool. Diagnostic accuracy measures were pooled using the random-effects model. Subgroup analysis was conducted by UBT type(13C vs 14C) and by measurement technique(Infrared spectrometry vs Isotope Ratio Mass Spectrometry).RESULTS: Out of 1380 studies identified, only 23 met the eligibility criteria. Fourteen studies(61%) evaluated 13 C UBT and 9 studies(39%) evaluated 14 C UBT. There was significant variation in the type of reference standard tests used across *** sensitivity was 0.96(95%CI: 0.95-0.97) andpooled specificity was 0.93(95%CI: 0.91-0.94). Likelihood ratio for a positive test was 12 and for a negative test was 0.05 with an area under thecurve of 0.985. Meta-analyses were associated with a significant statistical heterogeneity that remained unexplained after subgroup analysis. The included studies had a moderate risk of ***: UBT has high diagnostic accuracy for detecting H. pylori infection in patients with dyspepsia. The reliability of diagnostic meta-analytic estimates however is limited by significant heterogeneity.

关键词： Helicobacter pylori Dyspepsia Breath tests Urea/an

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Novel self assembly behavior for γ-alumina nanoparticles

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Particuology 2012年第6期10卷 744-750页

作者： osama Saber Physics Dept Faculty of ScienceKing Faisal UniversityAl-Hassa 31982P.O.Box 400Saudi Arabia Egyptian Petroleum Research Institute Nasr CityP.O.Box 11727CairoEgypt

In this study, self assembly behavior was induced for γ-alumina nanoparticles by adsorption of dimethyl disulfide. Following this trend, we have developed a chemical process to obtain ＇y-alumina in the nano scale. Scanning electron microscopy images of the prepared γ-alumina showed big and strong agglomeration of the nanoparticles indicating that these nanoparticles have strong surface forces. Transmission electron microscopy images confirmed that the γ-alumina nanoparticles 3-7 nm in size were converted to uniform spherical shape in the size range of 1-2 mm after shaking with dimethyl disulfide in the presence of n-hexane at room temperature. This phenomenon did not appear in the case of alumina in the micro scale. The surface properties of the prepared γ-alumina in the nano scale were characterized and compared with the γ-alumina in the micro scale by using low temperature nitrogen adsorption-desorption system, indicating that the specific surface area of the prepared γ-alumina nanoparticles is larger than that of the γ-alumina in the micro scale. Furthermore, micro- and meso-pores were observed for the if-alumina nanoparticles while only mesoporous structure was detected for the γ-alumina in the micro scale. These experimental results suggested that the self assembly behavior of the γ-alumina nanoparticles may be due to the selective adsorption ofdimethyl disulfide in the micropores of these nanoparticles to act as bridge linking the nanoparticles.

关键词： γ-Alumina nanoparticlesNovel self assembly behaviorScanning and transmission electronmicroscopy

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Improvement of sintering,nonlinear electrical,and dielectric properties of ZnO-based varistors doped with TiO2

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Chinese Physics B 2016年第6期25卷 575-580页

作者： osama A Desouky K E Rady Bilbis Higher Institute of Engineering (BHIE) Bilbis Sharqia Egypt Engineering Basic Sciences Department Faculty of engineering Menoufia University Shebin EI-Kom Egypt

The effects of TiO2 on sintering and nonlinear electrical properties of（98.5-x）ZnO–0.5MnO2–0.5Co2O3-0.5Bi2O3–xTiO2（x = 0.3,0.5,0.7,0.9 mol%） ceramic varistors prepared by the ceramic technique are investigated in this *** optimum sintering temperature of the prepared samples is deduced by determining the firing shrinkage and water absorption *** optimum sintering temperature is found to be 1200℃,at which each of the samples shows a maximum firing shrinkage and minimum water *** minimum water absorption appears in a sample of x = 0.9 mol%.Higher sintering temperature and longer sintering time give rise to a reduction in bulk density due to the increased amount of porosity between the large grains of ZnO resulting from the rapid grain growth induced by the liquid phase *** crystal size of ZnO decreases with increasing TiO2 *** addition of TiO2 improves the nonlinear coefficient and attains its maximum value at x = 0.7 mol% of TiO2,further addition negatively affects it.A decrease in capacitance consequently in the dielectric constant is recorded with increasing the frequency in a range of 30 kHz–200 *** temperature and composition dependences of the dielectric constant and AC conductivity are also *** increase of temperature raises the dielectric constant because it increases ionic response to the field at any particular frequency.

关键词： ZnO varistors water absorption nonlinear electrical properties dielectric constant

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Analysis of moose-vehicle collisions countermeasures in northern climates

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Transportation Safety and Environment 2021年第3期3卷 280-290页

作者： osama Abaza Colleen CMoran Department of Civil Engineering University of Alaska Anchorage3211 Providence DriveEIB 301LAnchorageAK 99508USA University of Alaska Anchorage 3211 Providence DriveEIB 301LAnchorageAK 99508USA

This research investigates the reliability of two measures intended to reduce moose-vehicle collisions(MVCs):continuous lighting and clearing/grubbing of roadway *** analyses and a combined regression analysis were conducted to measure the effects of several combinations of variables on MVC rates,including clearing and grubbing,continuous lighting,clearing without grubbing,moose population,precipitation,snowfall,and maximum snow *** corridor improvement projects were analyzed based on the variables *** previous studies,it has been hypothesized that MVC rates are influenced by environmental conditions such as snowfall and *** Alaska Department of Transportation and Public Facilities(DOT&PF)has performed many studies on MVCs along several *** corridors showed a significant drop in the number of MVCs after the installation of continuous *** results show there is a consistent drop in MVCs after clearing and grubbing,with the exception of one *** combined clearing/grubbing and continuous lighting projects also resulted in a consistent drop in *** projects with clearing and grubbing as a component had varying trends in MVCs,which may indicate that DOT&PF Maintenance and Operations performed clearing of re-vegetated areas,or that older growth is less of an attractant for moose.

关键词： continuous lighting clearing grubbing moose-vehicle collisions countermeasures cold regions wildlife

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Resistance to acid degradation,sorptivity,and setting time of geopolymer mortars

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Frontiers of Structural and Civil Engineering 2022年第6期16卷 781-791页

作者： osama A MOHAMED Rania AL-KHATTAB Waddah AL-HAWAT College of Engineering Abu Dhabi UniversityAbu DhabiUnited Arab Emirates

Experimental evaluations were conducted to determine the water sorptivity,setting time,and resistance to a highly acidic environment,of mortar with alkali-activated ground granulated blast furnace slag(GBS)binder and also of combinations of fly ash and GBS *** were activated using mixtures of NaOH and Na_(2)SiO_(3)*** molarity of NaOH in the mixtures ranged from 10 mol·L^(−1)to 16 mol·L^(−1),and the Na_(2)SiO_(3)/NaOH ratio was varied from 1.5 to *** samples were produced using three binder combinations:1)GBS as the only binder;2)blended binder with a slag-to-fly ash ratio of 3:1;and 3)mixed binder with 1:1 ratio of slag to fly *** samples were mixed and cured at(22±2)°C till the day of the *** impact of activator solution alkalinity,activator ratio Na_(2)SiO_(3)/NaOH,GBS content on the rate of water absorption were *** 7,28,and 90 d of immersion in a 10%sulfuric acid solution,the resistance of a geopolymer matrix to degradation was assessed by measuring the change in sample *** influence of solution alkalinity and relative fly ash content on setting times was ***-activated mortar with a slag-to-fly ash ratio of 3:1 had the least sorptivity compared to the two other binder combinations,at each curing age,and for mortars made with each of the NaOH alkaline activator *** sorptivity decreased with age and sodium hydroxide concentrations,suggesting the production of geopolymerization *** reduction in weight of sample occurred after immersion in the strong acid H_(2)SO_(4)solution for three months,regardless of binder *** was due to the synthesis of hydration and geopolymerization products in the presence of curing water,which outweighed the degradation of the geopolymer matrix caused by sulfuric acid.

关键词： alkali-activated materials fly ash sorptivity durability of concrete sodium hydroxide sodium silicates reduction in CO_(2)emissions sulfuric acid

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IL-6-deficient Mice Are Susceptible to Ethanol-induced Hepatic Steatosis:IL-6 Protects against Ethanol-induced Oxidative Stress and Mitochondrial Permeability Transition in the Liver

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Cellular & Molecular Immunology 2004年第3期1卷 205-211页

作者： osama El-Assal Won-HoKim SvetlanaRadaeva Section on Liver Biology Laboratory of Physiologic StudiesNational Institute on Alcohol Abuse and AlcoholismNational Institutes of HealthBethesdaMD 20892USA.

Interleukin-6(IL-6)-deficient mice are prone to ethanol-induced apoptosis and steatosis in the liver;however, the underlying mechanism is not fully *** dysfunction caused by oxidative stress is an early event that plays an important role in the pathogenesis of alcoholic liver ***,we hypothesize that the protective role of IL-6 in ethanol-induced liver injury is mediated via suppression of ethanol-induced oxidative stress and mitochondrial *** test this hypothesis,we examined the effects of IL-6 on ethanol-induced oxidative stress,mitochondrial injury,and energy depletion in the livers of IL-6(-/-)mice and hepatocytes from ethanol-fed *** consumption leads to stronger induction of malondialdehyde(MDA) in IL-6(-/-)mice compared to wild-type control mice,which can be corrected by administration of *** vitro, IL-6 treatment prevents ethanol-mediated induction of reactive oxygen species(ROS),MDA,mitochondrial permeability transition(MPT),and ethanol-mediated depletion of adenosine triphosphate(ATP)in hepatocytes from ethanol-fed *** of IL-6 in vivo also reverses ethanol-induced MDA and ATP depletion in ***,IL-6 treatment induces metallothionein protein expression,but not superoxide dismutase and glutathione peroxidase in cultured *** conclusion,IL-6 protects against ethanol-induced oxidative stress and mitochondrial dysfunction in hepatocytes via induction of metailothionein protein expression,which may account for the protective role of IL-6 in alcoholic liver *** & Molecular Immunology.2004;1(3):205-211.

关键词： IL-6 alcoholic liver injury oxidative stress mitochondria metallothionein

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A review of recent developments in CO_(2) mobility control in enhanced oil recovery

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Petroleum 2022年第3期8卷 291-317页

作者： osama Massarweh Ahmad S.Abushaikha Division of Sustainable Development College of Science and EngineeringHamad Bin Khalifa UniversityQatar FoundationDoha34110Qatar

Carbon dioxide-enhanced oil recovery(CO_(2)-EOR)has gained widespread attention in light of the declining conventional oil ***,CO_(2)-EOR contributes to the reduction of the global emissions of greenhouse gases through CO_(2) sequestration in subsurface geologic *** method has been largely used in the petroleum industry for several decades especially for extracting oil from light-to-medium oil reservoirs approaching an advanced state of ***,CO_(2) is used in a continuous flooding scheme for ***,continuous CO_(2) flooding tends to be problematic due to unfavorable mobility,viscous fingering/channeling and early breakthrough of CO_(2),especially in the presence of reservoir *** this paper,recent developments in the methods used to overcome these problems are *** developments include CO_(2)water-alternating-gas(WAG)injection,polymer-assisted CO_(2) injection,surfactant-assisted CO_(2) mobility control(CO_(2)-foam injection),and nanoparticle-assisted CO_(2) *** method addresses,to an extent,one or more of the problems associated with conventional CO_(2) ***,incorporating more than one method can provide better performance in terms of CO_(2) mobility control and oil *** comparison with CO_(2)-WAG and CO_(2)-foam injection methods,the use of polymers and nanoparticles with CO_(2) flooding is relatively *** two new methods were mostly investigated experimentally,at the laboratory level,and they still need further development prior to field implementation.

关键词： Mobility control CO_(2)-enhanced oil recovery Polymer thickeners Surfactants CO_(2)foam Nanoparticles

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Deep Learning Multimodal for Unstructured and Semi-Structured Textual Documents Classicatio

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Computers, Materials & Continua 2021年第7期68卷 589-606页

作者： Nany Katamesh osama Abu-Elnasr Samir Elmougy Faculty of Computers and Information Department of Computer ScienceMansoura University35516Egypt

Due to the availability of a huge number of electronic text documents from a variety of sources representing unstructured and semi-structured information,the document classication task becomes an interesting area for controlling data *** paper presents a document classication multimodal for categorizing textual semi-structured and unstructured *** multimodal implements several individual deep learning models such as Deep Neural Networks(DNN),Recurrent Convolutional Neural Networks(RCNN)and Bidirectional-LSTM(Bi-LSTM).The Stacked Ensemble based meta-model technique is used to combine the results of the individual classiers to produce better results,compared to those reached by any of the above mentioned models individually.A series of textual preprocessing steps are executed to normalize the input corpus followed by text vectorization *** techniques include using Term Frequency Inverse Term Frequency(TFIDF)or Continuous Bag of Word(CBOW)to convert text data into the corresponding suitable numeric form acceptable to be manipulated by deep learning ***,this proposed model is validated using a dataset collected from several spaces with a huge number of documents in every *** addition,the experimental results prove that the proposed model has achieved effective ***,upon investigating the PDF Documents classication,the proposed model has achieved accuracy up to 0.9045 and 0.959 for the TFIDF and CBOW features,***,concerning the JSON Documents classication,the proposed model has achieved accuracy up to 0.914 and 0.956 for the TFIDF and CBOW features,***,as for the XML Documents classication,the proposed model has achieved accuracy values up to 0.92 and 0.959 for the TFIDF and CBOW features,respectively.

关键词： Document classication deep learning text vectorization convolutional neural network bi-directional neural network stacked ensemble

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Advanced age and the clinical outcomes of transcatheter aortic valve implan-tation

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Journal of Geriatric Cardiology 2014年第2期11卷 163-170页

作者： osama Alsara Ahmad Alsarah Heather Laird-Fick Department of Internal Medicine Michigan State University B-301 Clinical Center East Lansing MI 48824 USA

Aortic valve stenosis （AS） is common in the elderly. Although surgical replacement of the valve has been the gold standard of management, many patients have been excluded from surgery because they were very old, frail, or had co-morbidities that increased operative risks. In the last decade, transcatheter aortic valve implantation （TAVI） has emerged as a new treatment option suitable for these patients. This article reviews the available literature on the role of TAVI in elderly patients with severe aortic stenosis. Published studies showed that elderly individuals who underwent TAVI experienced better in-hospital recovery, and similar short and mid-term mortality compared to those underwent surgical treatment of AS. However, long-term outcomes of TAVI in elderly patients are still unknown. The available data in the literature on the ef-fect of advanced age on clinical outcomes of TAVI are limited, but the data that are available suggest that TAVI is a beneficial and tolerable procedure in very old patients. Some of the expected complications after TAVI are reported more in the oldest patients such as vascular in-jures. Other complications were comparable in TAVI patients regardless of their age group. However, very old patients may need closer monitoring to avoid further morbidities and mortality.

关键词： Aortic stenosis Transcatheter aortic valve implantation Surgical aortic valve replacement Geriatric

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Ra's Abdah of the north Eastern Desert of Egypt:the role of granitic dykes in the formation of radioactive mineralization,evidenced by zircon morphology and chemistry

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Acta Geochimica 2016年第4期35卷 368-380页

作者： Ali A.Omran osama K.Dessouky Nuclear Materials Authority P.O.Box 530El MaadiCairoEgypt

Syenogranitic dykes in the north of Egypt's Eastern Desert are of geological and economic interest because of the presence of magmatic and supergene enrichment of radioactive mineralization. Zircon crystal morphology within the syenogranitic dykes allows precise definition of sub-alkaline series granites and crystallized at mean temperature of about 637 °C. The growth pattern of the zircons suggest magmatic and hydrothermal origins of radioactive mineralization. Hydrothermal processes are responsible for the formation of significant zircon overgrowth; high U-zircon margins might have occurred contemporaneously with the emplacement of syenogranitic dykes which show anomalous uranium(e U) and thorium(e Th) contents of up to 1386 and 7330 ppm, *** chemistry revealed a relative increase of Hf consistent with decreasing Zr content, suggesting the replacement of Zr by Hf during hydrothermal *** uranium mineralization is present and recognized by the presence of uranophane and autunite.

关键词： Syenogranitic dykes Zircon Morphology Typology Uranium Egypt

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