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Geotectonic significance of the Neoproterozoic ophiolitic metagabbros of Muiswirab area,South Eastern Desert,Egypt:constraints from their mineralogical and geochemical characteristics

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Acta Geochimica 2020年第6期39卷 887-910页

作者： Moustafa M.Mogahed Wlaa mahmoud saad Geology Department Faculty of ScienceBenha University-EgyptP.O.Box 13518BenhaEgypt

Petrological and geochemical studies of Neo-proterozoic metagabbros were carried out in the Muiswirab area,South Eastern Desert of *** Muiswirab area comprises of ophiolitic metagabbroic rocks(MOM),which are tectonically thrusted over a thick pile of metavolcanic rocks and intruded by syn-and post-tectonic granitoid *** whole-rock geochemical variations coupled with chemical compositions of mineral constituents are used to attain the genesis and tectonic evolution of the studied *** geothermobarometric investiga-tion of the analyzed amphiboles from(MOM)revealed that these metagabbros underwent regional metamorphism under lower to upper greenschist facies(biotite zone)conditions(at a temperature of 450 to 500℃and pressure of 1-3 kbar).Geochemically,the metagabbros(MOM)show tholeiitic affinity and cxhibiting both arc-and MORB-like characters as evidenced by their clinopyrox-ene compositions and the Ti/V ratios(11.84-31.65),which considered as prominent features of forearc tectonic *** geochemical features suggest a probable fractionation of olivine±clinopyroxene±plagioclase as well as insignificant crustal *** parental magma of the investigated MOM rocks seems to be developed in a sub-arc mantle wedge setting due to the enrichments of LILE(e.g..Rb,Ba,Sr,Pb)over HFSE(e.g,Ti,Nb,Y,Zr,Hf,Ta).The studied MOM rocks have lower values of Nb/U relative to MORB and OIB indicating that their geochemical variation produced due to the enrichment of a lithosphere mantle by OIB like *** ratios of Zn/Fet,La/Sm,Sm/Yb,Th/Yb and Nb/Yb indicate that the MOM rocks represent a fragment of oceanic crust originated at a supra-subduction zone environment and their parental magma developed by 5-30%partial melting of a spinel lherzolite mantle rather than pyroxenite in an island arc setting and conformable with most of the Egyptian ophiolitic metagabbros.

关键词： Egypt Eastern Desert Muiswirab area Ophiolitic metagabbros N-MORB Arc tholeiites Foreare tectonic regime Volcanic-arc setting

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A System of Sylvester-type Quaternion Matrix Equations with Ten Variables

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Acta Mathematica Sinica,English Series 2022年第8期38卷 1399-1420页

作者： Meng Yan XIE Qing Wen WANG Zhuo Heng HE Mehany mahmoud saad Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

This paper studies a system of three Sylvester-type quaternion matrix equations with ten variables A_(i)X_(i)+Y_iB_(i)+C_(i)Z_(i)D_(i)+F_(i)Z_(i+1)G_(i)=E_(i),i=1,3^-.We derive some necessary and sufficient conditions for the existence of a solution to this system in terms of ranks and Moore–Penrose inverses of the matrices *** present the general solution to the system when the solvability conditions are *** applications of this system,we provide some solvability conditions and general solutions to some systems of quaternion matrix equations involvingφ-***,we give some numerical examples to illustrate our *** findings of this paper extend some known results in the literature.

关键词： Quaternion matrix equation φ-Hermitian solution general solution solvability

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Treatment of COVID-19 by Controlling the Activity of the Nuclear Factor-Kappa B

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CellBio 2020年第2期9卷 109-121页

作者： mahmoud saad Mohamed Elkhodary General Organization for Exporting and Importing Control Suez Egypt

Heavy infection of the virus leads to overproduction of cytokines. The overproduction of cytokine (cytokines storms) is responsible for the critical cases and deaths of COVID-19. The nuclear factor kappa-B stimulates the expression of the genes, which is responsible for cytokines storm and RNA transcription. The COVID-19 virus can be controlled by inhibition of nuclear factor kappa-B. Nuclear factor kappa-B is controlled by inhibition of hydrogen peroxide and inhibitor kappa-B kinase enzyme.

关键词： Cytokine Storm COVID-19 Nuclear Factor Kappa-B

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Quranic Verse No. 8 of Surat Al-Jumu’ah Leads us to Describe Cancer and Determine Its True Cause (Part-III)

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CellBio 2018年第2期7卷 35-49页

作者： mahmoud saad Mohamed El-Khodary Department of Veterinary Medicine Zagazig University Zagazig Egypt Department of Fish Diseases Suez Canal University Ismailia Egypt General Organization for Export and Import Control Suez Egypt

Therapeutic strategies for destroying cancer cells by making its death programs run again. The normal cell passes through several stages (Accumulation stage, Detoxification stage, Formation of free radical stage and Activation of nuclear factor kappa B stage and the shutting down of programs of cell death stage) to become a cancerous cell. The success of the therapeutic strategy to treat cancer depends on making either one or both programs of cell death run again. Shutting down one stage completely will be sufficient to stop the transformation of the natural cell into a cancerous cell, which eliminates the production of hydrogen peroxide, thus the activity of the NF-Kb will be inhibited. However, shutting down all stages is the most comprehensive therapeutic strategy and guarantees treatment success.

关键词： Cancer Therapeutic Strategy Accumulation Detoxification Enzymes Free Radicals Antioxidants H2O2 Glutathione NF-Kb Sulforaphane Flavonoid Cur Cumin

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Cell Fleeing from Death Phenomenon

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CellBio 2020年第1期9卷 1-13页

作者： mahmoud saad Mohamed El-Khodary General Organization for Export and Import Control Suez Egypt

Cell fleeing from death phenomenon occurs as either complete or incomplete;the phenomenon is incomplete fleeing from death when cell blocks intrinsic death program only. But, it becomes complete fleeing from death if the cell successfully blocks the pathway of intrinsic and extrinsic programs of cell death. This phenomenon is induced by the formation of hydrogen peroxide which activates nuclear factor kappa B. The nuclear factor-kappa B stimulates the expression of several genes, to produces 6 factors (BcL-2, Muc-1, MMPs, DcR3, Muc-4, muc-16, and TNF-α). Such factors act as blockers of the pathway of intrinsic and extrinsic programs of cell death. These blockers convert normal cell to a cancer cell. If these blockers are removed, the death programs of cancer cells will run again and cancer will disappear.

关键词： Phenomenon Apoptosis Cancer

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Quranic Verse No. 8 of Surat Al-Jumu’ah Describes Cancer as a Complete and Accurate Description and Leads Us to Determine the True Cause of Cancer. “Part-1”

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CellBio 2018年第1期7卷 1-11页

Cancer is the cell fleeing from death by blocking the pathways of the intrinsic and the extrinsic program of cell death (Apoptosis). The success depends on making the programs of cell death run again.

关键词： Cancer Description Intrinsic Apoptosis Extrinsic Apoptosis

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Management of Post-Craniotomy Persistent CSF Subgaleal Collection in Skull Base Procedures: Local Experience

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Open Journal of Modern Neurosurgery 2020年第1期10卷 114-121页

作者： Hosam Shata mahmoud saad Ahmed Nageeb Taha Neurosurgery Department Mansoura University Mansoura Egypt

Background: Post-craniotomy CSF collection is a problem that may cause severe complications as meningitis, wound disruption, prolonged hospitalization, and additional surgeries. Objective: To evaluate our cases with resistant post-operative subgaleal CSF collection, trying to identify causes and optimal management. Methods: Retrospective review of elective skull base cases during the period of January 2104 to January 2019 identification of cases with post-operative CSF subgaleal collection, which either managed conservatively or needed a second surgery. Results: 219 patients, 30 of them suffered subgaleal CSF collection, 22 patients improved with non-operative measures, eight patients needed second surgery with pericranial graft augmentation, and obliteration of subgaleal space resulted in resolution of CSF leak with no morbidities. Conclusion: Meticulous tensionless dural closure, obliteration of subgaleal space, tethering of dural grafts to bone edges are useful techniques in preventing post-operative CSF leak.

关键词： Subgaleal CSF Post-Operative Dural Repair Craniotomy

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互联网上市公司高管持股比例与公司绩效关系研究

互联网上市公司高管持股比例与公司绩效关系研究

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作者： saad mahmoud HASSAN IBRAHIM ELAMIR 北京工业大学

学位级别：硕士

近年来,全球经济一体化的不断发展,如何加强企业管理提升企业效益成为了一个重要的研究课题。在国外发达国家上市企业管理过程中,给予公司高管一定的持股比例已经成为一种普遍的现象。在中国随着股权分置改革的不断发展,在市场经济快速... 详细信息

近年来,全球经济一体化的不断发展,如何加强企业管理提升企业效益成为了一个重要的研究课题。在国外发达国家上市企业管理过程中,给予公司高管一定的持股比例已经成为一种普遍的现象。在中国随着股权分置改革的不断发展,在市场经济快速发展的情形下,国家鼓励企业上市发展,从而进一步提升中国企业的全球竞争实力。目前在中国上市企业中也在逐步推行股权激励措施,从而使企业高管能够获得一定程度的激励,从而能够更好的推动企业发展。对于中国而言当今互联网经济发展迅速,互联网上市公司的发展带有明显的时代性,并且在这些上市公司中但高管持股已经非常普遍。在本文的研究中以2014-2015年中国互联网上市公司为研究对象,深入分析这些企业中高管持股和公司绩效之间的关系,其中主要包括了两方面的内容,一是探求二者之间的因果关系,二是深入探讨高管股权占比以及持股结构对公司绩效所形成的关系,从而能够为中国在网上是公司的发展提供必要的有益建议。在本课题的研究中,详细调查和整理了国内外针对高管持股和企业绩效之间关系的相关文献以及成果,通过对这些资料的学习,明确了本课题研究的重要意义。在本文的论述中主要从两个方面对二者之间的关系进行探讨,一是二者之间的因果关系,二是二者之间的相关性以及对企业绩效的影响。本研究课题是在互联网经济迅速发展的时代而提出的,所以本文选择了2014-2015年互联网上市公司作为研究对象,并展开数据样本实证分析,其中构建了研究的因果性模型以及相关性模型进行系统性分析。得出了如下研究结论:（1）通过本文的研究可以看出,在互联网上市企业中企业高管持股和公司绩效之间存在着明显的因果关系。其中企业管理层是因,而上市企业绩效作为果,体现出明显的上市企业给予高管股份以后的激励作用。借助对总样本和分样本的高管持股与公司绩效的回归,本文发现:在回归模型一中,高管持股对公司绩效有提升作用,也就是说当上市企业给予高管一定的股权以后,能够有效的推动高管的主管能动性,使其能够与公司利益保持一致,促进企业向着更好的方向发展,有效的减少了这些企业高管的短期行为,有效推动了企业发展的高效性。（2）将总样本分为国有和非国有,国有企业回归中,高管持股对企业绩效不显著,即高管持股作为一种激励手段,对公司绩效的提升效果不佳。在国有企业中,国家作为第一大股东,对企业产生绝对的控制权,在整个公司管理运营中,董事长和总经理处于顶点的位置,对企业的生存和发展有决定性影响,而在国有企业中,这些管理人员占有公司的股份相对较少,甚至没有股份,造成国有企业高管持股对企业绩效的影响不显著。（3）非国有企业中,得出的结果与总样本相同,即高管持股对企业绩效产生正向的显著性水平。非国有企业发展过程中通过合理分配企业股权,同时更加注重企业发展效率的角度出发,能够对企业高管进行覆盖式、公平性激励,进而导致非国有企业高管持股对企业绩效的影响高于国有企业。（4）互联网行业企业之外的企业,在高管持股的情况下,其与企业的绩效同样是显著为正的,这也再次说明,无论是互联网行业还是其他行业,高管持股确实能够改善企业的绩效,也就是企业绩效与高管持股是显著正相关的。（5）国际贸易互联网公司高管持股,同样是与企业绩效是正相关,这是基于互联网行业的基础上进行的细分研究,通过实证研究,同样得出了一致的结论。

关键词：高管持股持股比例持股结构公司绩效互联

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Microsurgical Management of Vestibular Schwannomas with Brainstem Compression: Surgical Challenges and Outcome

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Open Journal of Modern Neurosurgery 2020年第1期10卷 122-134页

作者： mahmoud saad Hosam Shata Mohamed Younis Ahmed Nageeb Mohamed Taha Department of Neurosurgery Faculty of Medicine Mansoura University Mansoura Egypt Department of Anesthesiology Faculty of Medicine Mansoura University Mansoura Egypt

Background: Vestibular schwannomas exerting brainstem compression with or without hydrocephalus are challenging for neurosurgeons regarding the plan of surgery, operative risk and postoperative sequale. Purpose: To report our experience with the surgical challenges and outcomes for Hannover type T4a & T4b vestibular schwannomas. Methods: Retrospective case study conducted at neurosurgery department, Mansoura University between October 2016 and May 2019 of 16 patients with vestibular schwannoma compressing the brainstem. We reviewed their clinical, radiological, surgical data, incidence of complications and outcome. Results: We had 16 patients: 10 of Hanover grade T4b and 6 of grade T4a. Gross total resection was achieved in 2 cases while subtotal resection was achieved in 5 cases and in the remaining 9 cases;only partial resection was feasible. We had 4 cases of mortality. Among new onset morbidity after surgery, 3 cases had post-operative bulbar manifestation and 4 cases had brainstem dysfunction. Conclusion: Vestibular schwannomas compressing the brain stem are challenging in their clinical presentation, surgery and post-operative outcome. The outcome of patients treated with hydrocephalus prior to vestibular schwannoma surgery is better than those who did initial VS surgery. Patients presented with significant brainstem, bulbar manifestation had worse outcome and needed longer ICU stay and longer time for recovery.

关键词： Brainstem Challenges Vestibular Schwannoma

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基于图像处理的笔迹防伪检测方法

基于图像处理的笔迹防伪检测方法

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作者：阿莫尔（AMR saad mahmoud MEGAHED）哈尔滨工业大学

学位级别：硕士

在各种犯罪活动中文档伪造是一种常见的伪装手段,由于其易于实施而难于分辨,文档伪造的检测技术显得更加重要而迫切,通过对文档中笔迹改动的检测辨别文档真伪是其中重要的手段。然而,篡改者往往使用相近颜色的墨水对文档进行篡改,因此... 详细信息

在各种犯罪活动中文档伪造是一种常见的伪装手段,由于其易于实施而难于分辨,文档伪造的检测技术显得更加重要而迫切,通过对文档中笔迹改动的检测辨别文档真伪是其中重要的手段。然而,篡改者往往使用相近颜色的墨水对文档进行篡改,因此往往无法靠眼睛进行分辨。数字图像处理的方法提供更加精细的分辨能力,因此为这一问题带来新的解决方案。本文针对文档篡改中的笔迹检测问题,提出了两种基于图像处理的检测方法。论文的主要创新性工作包括:首先,综述并分析了用于笔记检测的重要图像特征,对比了不同的色彩空间表达。鉴于基于数字图像的笔迹检测算法目前缺少测试样本,我们首先建立了一个包含各种篡改情况的样本库,并通过扫描仪对样本进行数字化,得到了一个数字图像样本库,为后续的算法研究提供支撑;第二,提出了一种基于RGB特征距离的篡改笔迹检测方法,通过提取RGB通道的9个特征并计算特征与文档中所有目标的距离进行检测。首先文档被分割成独立的目标对象,然后计算每个目标对象的9个特征,以及用均方根误差表示的两两特征向量之间的距离。然后通过改进的Thompson Tau算法检测异常点并进行第二轮异常点检测。实验证明了所提出方法在检测和定位方面的能力;第三,提出了一种基于颜色直方图结构相似性的篡改笔迹检测方法,在对分档进行目标分隔之后,基于每一个目标图像块的RGB通道的直方图构造特征向量,通过结构相似性指标来衡量特征向量之间的相似度,最后通过相似度阈值检测异常目标。实验结果表明针对替换和添加等攻击,该算法具有较高的检测准确度。

关键词：篡改笔迹检测文档检测相似度指标颜色直方图异常值检测

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