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Petroleum Science 2012年第3期9卷 389-399页

作者： Ahmed El-mekabaty Osman m.O.Habib hussein m.hassan Evelin B.moawad Department of Chemistry Faculty of ScienceMansoura University

Oxazolone derivative 2 was utilized as a key intermediate for synthesis of some new oxazolone and imidazolone derivatives. Reaction of oxazolone derivative 2 with diamines under different conditions afforded the corresponding imidazolone derivatives 3-8, respectively. moreover, oxazolone 2 reacted with some heterocyclic amines in glacial acetic acid giving the corresponding imidazolone derivatives 9-14, respectively. Cyclocondensation of thiosemicarbazide with compound 2 in dry pyridine afforded compound 15. Addition of secondary amines to olefin double bond of compound 2 gave the corresponding addition products 16-19, respectively. michael addition of compound 2 with some active methylene compounds afforded oxazolone derivatives 20-23, respectively. These prepared products were evaluated as antioxidant and corrosion inhibitors for gasoline lubricating oil and compounds 6a-e, 10 and 15 exhibited the highest antioxidant and anticorrosive activities. The effect of concentration of additives was studied to recommend the optimum concentration to be used. The results showed, for additive 15, 0.1 g for 1 L oil was the more effective concentration. measurements for thermal analysis and of surface tension of oil after oxidation were also carried out.

关键词： Oxazolone imidazolone benzoimidazole surface tension thermal stability antioxidant additives.

Gene therapy for liver regeneration:Experimental studies and prospects for clinical trials

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World Journal of Gastroenterology 2010年第32期16卷 4019-4030页

作者： hussein m Atta Department of Surgery Faculty of MedicineMinia UniversityMisr-Aswan RoadEl-Minia 61519Egypt

The liver is an exceptional organ,not only because of its unique anatomical and physiological characteristics,but also because of its unlimited regenerative *** of the molecular mechanisms that govern liver regeneration has allowed researchers to exploit them to augment liver *** progress in the field,however,was made by the introduction of the powerful tool of gene *** of genetic materials,such as hepatocyte growth factor,using both viral and non-viral vectors has proved to be successful in augmenting liver regeneration in various animal *** future clinical studies,ongoing research aims at eliminating toxicity of viral vectors and increasing transduction efficiency of non-viral vectors,which are the main drawbacks of these *** goal of current research is to develop gene therapy that targets specific liver cells using receptors that are unique to and highly expressed by different liver cell *** outcome of such investigations will,undoubtedly,pave the way for future successful clinical trials.

关键词： Liver regeneration Gene therapy Genetic vectors Growth factors

Prevention of peritoneal adhesions:A promising role for gene therapy

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World Journal of Gastroenterology 2011年第46期17卷 5049-5058页

作者： hussein m Atta Department of Surgery Faculty of MedicineMinia University

Adhesions are the most frequent complication of abdominopelvic surgery,yet the extent of the problem,and its serious consequences,has not been adequately *** evolved as a life-saving mecha-nism to limit the spread of intraperitoneal inflammatory *** different pathophysiological mechanisms can independently trigger adhesion *** cell injury and loss during operations,tissue hypoxia and inflammation each promotes adhesion formation separately,and potentiate the effect of each *** have repeatedly demonstrated that interruption of a single pathway does not completely prevent adhesion *** review summarizes the pathogenesis of adhesion formation and the results of single gene therapy *** explores the prom-ising role of combinatorial gene therapy and vector modif ications for the prevention of adhesion formation in order to stimulate new ideas and encourage rapid advancements in this field.

关键词： Peritoneal adhesions Tissue plasminogen activator Gene therapy Plasminogen activator inhibi-tor Tissue inhibitor of metalloproteinase Transforminggrowth factor β

Reversibility and heritability of liver fibrosis:Implications for research and therapy

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World Journal of Gastroenterology 2015年第17期21卷 5138-5148页

作者： hussein m Atta Department of Surgery Faculty of MedicineMinia UniversityEl-Minia 61519Egypt

Liver fibrosis continues to be a major health problem worldwide due to lack of effective *** the etiology cannot be eliminated,liver fibrosis progresses to cirrhosis and eventually to liver failure or malignancy;both are associated with a fatal *** transplantation,the only curative therapy,is still mostly *** fibrosis was shown to be a reversible process;however,complete reversibility remains ***,the molecular markers of liver fibrosis were shown to be transmitted across *** mechanisms including DNA methylation,histone posttranslational modifications and noncoding RNA have emerged as major determinants of gene expression during liver fibrogenesis and ***,epigenetic mechanisms have been shown to be transmitted through mitosis and meiosis to daughter cells and subsequent ***,the exact epigenetic regulation of complete liver fibrosis resolution and inheritance has not been fully *** communication will highlight the recent advances in the search for delineating the mechanisms governing resolution of liver fibrosis and the potential for multigenerational and transgenerational transmission of fibrosis *** fact that epigenetic changes,unlike genetic mutations,are reversible and can be modulated pharmacologically underscores the unique opportunity to develop effective therapy to completely reverse liver fibrosis,to prevent the development of malignancy and to regulate heritability of fibrosis phenotype.

关键词： Epigenetics Epimutations Inheritance Livercirrhosis Hepatic stellate cells Histone modification DNA methylation microRNA Long noncoding RNA Transcription regulation

Synthesis, Characterization and Corrosion Inhibitive Properties of New Thiazole Based Polyamides Containing Diarylidenecyclohexanone moiety

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Chinese Journal of Polymer Science 2015年第1期33卷 1-13页

作者： K.I.Aly m.A.hussein Polymer Chemistry Lab. 122 Chemistry Department Faculty of Science Assiut University Assiut 71516 Egypt Chemistry Department Faculty of Science King Abdulaziz UniversityJeddah 21589 Kingdom of Saudi Arabia

The present work aimed to synthesize a new interesting series of thiazole based polyamides containing diarylidenecyclohexanone moiety 5a-5f using low temperature solution polycondensation technique. The new polymers were synthesized by the reaction of thiazole based monomer namely, bis（2-aminothiazol-4-ylbenzylidene）cyclohexanone 3 with different aliphatic and aromatic diacid chlorides using NmP, and in the presence of anhydrous Li Cl as catalyst. Adipoyl, sebacoyl, oxaloyl, terephthaloyl, isophthaloyl dichlorides and biphenyl dicarbonyl dichloride were used as diacid chlorides. The structure of the model compound 4 as well as the new polymers was confirmed by correct elemental and spectral analyses. The thermal properties of those polymers were evaluated by TGA and DTG measurements and correlated to their structural units, beside X-ray diffraction analysis, solubility and viscometry measurements. The inherent viscosities for the synthesized polymers were in the range 0.6–1.03 d L/g. On the other hand the corrosion inhibitive properties of monomer 3 as well as polyamides 5d and 5f as selected examples were carried out on carbon-steel in 0.5 mol/L H2SO4 at 40 °C. The calculated inhibition efficiency（IE%） for polymer 5d was in the range（82 ± 6）% in all selected concentrations. The best value of IE% was obtained at 1 mg/L to reach 98.24% for polymer 5d and at 0.5 mg/L to reach 87.75% for polymer 5f.

关键词： Diarylidenecyclohexanone Polyamides Synthesis Characterization Thiazole Corrosion inhibitive properties.

Adsorption and desorption of acetone by TiO_(2) clusters:Transition state theory and sensing analysis

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ChemPhysmater 2023年第4期2卷 351-355页

作者： mudar Ahmed Abdulsattar Tasneem.hassan mahmood hussein Hakim Abed Hayder m.Abduljalil Department of Pharmacy Al-Rasheed University CollegeBaghdad 10011Iraq ministry of Science and Technology Baghdad 10011Iraq Department of Physics College of Science for WomenUniversity of BaghdadBaghdad 10011Iraq Department of Physics College of ScienceUniversity of BabylonBabylon 51005Iraq

TiO_(2) cluster sensitivity to acetone adsorption using transition state theory is ***_(10)O_(20) cluster is used to perform the calculations using density functional theory with dispersion *** state and transition state are calculated via thermodynamic energies,i.e.,Gibbs free energy of adsorption and *** rate,response,response time,and recovery time as a function of temperature and acetone concentration are *** burning in the air due to autoignition is considered using a logistic *** results of the theory are compared with available experimental findings that revealed the quality of both theoretical and experimental *** response time decreases with respect to acetone *** the other hand,the recovery time in the desorption phase increases with acetone *** temperature of maximum response is 356℃,while the maximum response value is 2.9.

关键词： TiO_(2) Acetone Transition state Sensor Density functional theory

Thermodynamics of the Bardeen Regular Black Hole

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Chinese Physics Letters 2012年第7期29卷 25-28页

作者： m.Akbar Nema Salem S.A.hussein Effat University Jeddah 21478Kingdom of Saudi Arabia

We deal with the thermodynamic properties of the Bardeen regular black hole with reference to their respective *** is argued here that the expression of the heat capacity at horizons is positive in one parameter region and negative in the other,and between them the heat capacity diverges where the black hole undergoes the second-order phase transition.

关键词： transition Regular Thermodynamics

The Response of the Earth's Lower Ionosphere to Gamma-Ray Solar Flares and their Associated X-ray

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Research in Astronomy and Astrophysics 2022年第4期22卷 137-152页

作者： mahmoud mohery hussein m.Farid Alaa Ali Dept.of Phys College of ScienceUniversity of JeddahJeddahSaudi Arabia Astronomy Space Science&Meteorology DepartmentFaculty of ScienceCairo UniversityGiza 12613Egypt Astronomy Dept. Faculty of ScienceKing Abdulaziz University21589 JeddahSaudi Arabia

The present work aims to explore the impact of solar gamma-ray fiares(GRFs),detected by the Fermi-Large Area Telescope(LAT),and their associated X-ray fiares(XRFs)on the Earth’s lower *** data of ionospheric parameter fmin were collected from the Yamagawa mid-latitude ionosonde station in *** most of the GRFs used in this study are associated with soft X-ray(SXR)emissions,detected by the Geostationary Operational Environmental Satellite(GOES),we classified them into three types:simultaneous(S),delayed(D)and not associated(N),refiecting the phase occurrence of the solar ***,the ionospheric D layer responds strongly to XRFs more than *** temporal profiles of the ionospheric parameter fmin show distinct behaviors as a response to the various GRF *** the case of the S-type,a single strong peak,with an average value of 5.2 mHz,emanates in the fmin profile within an average interval of time of less than half an *** the case of the D-type,two successive peaks appear in the fmin profile,with an average value of 6.0 mHz for the second peak through a time interval of one hour after the onset of gamma-ray(GR)*** response of the fmin parameter to the N-type fiares appears as a single peak with an average value of 4.8 mHz within about an *** notice that the difference between the fmin peak values and the corresponding reference ones(dfmin)is more convenient and representative than the fmin values,where the median GR fiux of the S-,D-and N-types tends to increase as the average dfmin increases.

关键词： Sun:X-rays gamma-rays Earth:ionosphere satellites

Energy Efficient Scheduler of Aperiodic Jobs for Real-time Embedded Systems

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International Journal of Automation and computing 2020年第5期17卷 733-743页

作者： hussein El Ghor El-Hadi mAggoune University Institute of Technology Lebanese UniversityLebanon Sensor Networks and Cellular Systems(SNCS)Research Center UTSaudi Arabia Electrical Engineering Department University of Tabuk Sensor Networks and Cellular Systems(SNCS)Research Center 71491 TabukSaudi Arabia

Energy consumption has become a key metric for evaluating how good an embedded system is,alongside more performance metrics like respecting operation deadlines and speed of *** improvement is no longer the only metric by which optimality is *** fact,energy efficiency is becoming a preferred choice with a fundamental objective to optimize the system's *** this work,we propose an optimal energy efficient scheduling algorithm for aperiodic real-time jobs to reduce CPU energy ***,we apply the concept of real-time process scheduling to a dynamic voltage and frequency scaling(DVFS)*** address a variant of earliest deadline first(EDF)scheduling algorithm called energy saving-dynamic voltage and frequency scaling(ES-DVFS)algorithm that is suited to unpredictable future energy production and irregular job *** prove that ES-DVFS cannot attain a total value greater than C/ˆSα,whereˆS is the minimum speed of any job and C is the available energy *** also investigate the implications of having in advance,information about the largest job size and the minimum speed used for the competitive factor of *** show that such advance knowledge makes possible the design of semi-on-line algorithm,ES-DVFS∗∗,that achieved a constant competitive factor of 0.5 which is proved as an optimal competitive *** experimental study demonstrates that substantial energy savings and highest percentage of feasible job sets can be obtained through our solution that combines EDF and DVFS optimally under the given aperiodic jobs and energy models.

关键词： Real-time systems energy efficiency aperiodic jobs scheduling dynamic voltage scaling low-power systems embedded systems

A Bit-level Text Compression Scheme Based on the ACW Algorithm

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International Journal of Automation and computing 2010年第1期7卷 123-131页

作者： hussein Al-Bahadili Shakir m. Hussain Arab Academy for Banking and Financial Sciences Faculty of Information Technology Petra University

This paper presents a description and performance evaluation of a new bit-level, lossless, adaptive, and asymmetric data compression scheme that is based on the adaptive character wordlength （ACW（n）） algorithm. The proposed scheme enhances the compression ratio of the ACW（n） algorithm by dividing the binary sequence into a number of subsequences （s）, each of them satisfying the condition that the number of decimal values （d） of the n-bit length characters is equal to or less than 256. Therefore, the new scheme is referred to as ACW（n, s）, where n is the adaptive character wordlength and s is the number of subsequences. The new scheme was used to compress a number of text files from standard corpora. The obtained results demonstrate that the ACW（n, s） scheme achieves higher compression ratio than many widely used compression algorithms and it achieves a competitive performance compared to state-of-the-art compression tools.

关键词： Data compression bit-level text compression ACW(n) algorithm Huffman coding adaptive coding