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Explanation of Pressure Effect for High Temperature Superconductors Using Pressure Dependent Schrodinger Equation and String Theory

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Natural Science 2020年第1期12卷 28-34页

作者： Einas Mohamed ahmed Mohamed nagwa idriss ali ahmed Musa Ibrahim Babiker Hussein Rasha Abd Elhai Mohammad Taha Mohammed idriss ahmed Mubarak Dirar Abd-Alla Department of Physics University College (Turaba) Taif University Taif KSA Department of Physics and Mathematics Hantoub Faculty of Education Algezira University Wad Madaniin-Hantoub Sudan Department of Physics Faculty of Science & Art (Dariyah) Qassim University Al-Mulida KSA Department of Physics and Mathematics Faculty of Education Albutana University Rufaa Sudan Department of Physics Faculty of Science & Art Dariyah University Buljurashi KSA Department of Physics College of Science Majmaah University Majmaah KSA Department of Physics Faculty of Science Sudan University of Science and Technology Khartoum Sudan

A pressure dependent Schrodinger equation is used to find the conditions that lead to superconductivity. When no pressure is exerted, the superconductor resistance vanishes beyond a critical temperature related to the repulsive force potential of the electron gass, where one assuming the electron total energy to be thermal, where applying mechanical pressure destroys Sc when it exceeds a certain critical value. However when the electron total energy is an assumed to be that of the free electron model and that the pressure is thermal and mechanical, the situation is different. The quantum expression for resistance shows that the increase of mechanical pressure increases the critical temperature. Such phenomenon is observed in high temperature cupper group.

关键词： Pressure Dependent Schrodinger Equation Superconductivity Critical Temperature Pressure High Temperature Superconductor

Safety and outcome of treatment of metastatic melanoma using 3-bromopyruvate: a concise literature review and case study

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Chinese Journal of Cancer 2014年第7期33卷 356-364页

作者： Salah Mohamed El Sayed Walaa Gamal Mohamed Minnat-Allah Hassan Seddik Al-Shimaa ahmed ahmed Asmaa Gamal Mahmoud Wael Hassan Amer Manal Mohamed Helmy Nabo ahmed Roshdi Hamed nagwa Sayed ahmed ali Abdel-Rahman Abd-Allah Department of Medical Oncology and Nuclear Medicine Sohag Faculty of Medicine Sohag University Department of Medical Biochemistry and Molecular biology Sohag Faculty of Medicine Sohag University Department of Surgery Sohag Cancer Center Department of Pediatrics Sohag Teaching Hospital Division of Pediatric Cardiology Department of Pediatrics Maternity and Children Hospital King Abdullah Medical City Al-Madinah Al-Munawwarah Kingdom of Saudi Arabia Department of Pathology Sohag Faculty of Medicine Sohag University

3-Bromopyruvate(3BP) is a new, promising anticancer alkylating agent with several notable functions. In addition to inhibiting key glycolysis enzymes including hexokinase II and lactate dehydrogenase(LDH), 3BP also selectively inhibits mitochondrial oxidative phosphorylation, angiogenesis, and energy production in cancer cells. Moreover, 3BP induces hydrogen peroxide generation in cancer cells(oxidative stress effect) and competes with the LDH substrates pyruvate and lactate. There is only one published human clinical study showing that 3BP was effective in treating fibrolamellar hepatocellular carcinoma. LDH is a good measure for tumor evaluation and predicts the outcome of treatment better than the presence of a residual tumor mass. According to the Warburg effect, LDH is responsible for lactate synthesis, which facilitates cancer cell survival, progression, aggressiveness, metastasis, and angiogenesis. Lactate produced through LDH activity fuels aerobic cell populations inside tumors via metabolic symbiosis. In melanoma, the most deadly skin cancer, 3BP induced necrotic cell death in sensitive cells, whereas high glutathione(GSH) content made other melanoma cells resistant to 3BP. Concurrent use of a GSH depletor with 3BP killed resistant melanoma cells. Survival of melanoma patients was inversely associated with high serum LDH levels, which was reported to be highly predictive of melanoma treatment in randomized clinical trials. Here, we report a 28-year-old man presented with stage IV metastatic melanoma affecting the back, left pleura, and lung. The disease caused total destruction of the left lung and a high serum LDH level(4,283 U/L). After ethics committee approval and written patient consent, the patient received 3BP intravenous infusions(1-2.2 mg/kg), but the anticancer effect was minimal as indicated by a high serum LDH level. This may have been due to high tumor GSH content. On combining oral paracetamol, which depletes tumor GSH, with 3BP treatment, se

关键词：黑色素瘤治疗文献综述溴代转移性乳酸脱氢酶对乙酰氨基酚 GSH含量

The Performance of Robust Methods in Logistic Regression Model

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Open Journal of Statistics 2020年第1期10卷 127-138页

作者： idriss Abdelmajid idriss ahmed Weihu Cheng College of Applied Science Department of Statistics Beijing University of Technology Beijing China

Logistic regression is the most important tool for data analysis in various fields. The classical approach for estimating parameters is the maximum likelihood estimation, a disadvantage of this method is high sensitivity to outlying observations. Robust estimators for logistic regression are alternative techniques due to their robustness. This paper presents a new class of robust techniques for logistic regression. They are weighted maximum likelihood estimators which are considered as Mallows-type estimator. Moreover, we compare the performance of these techniques with classical maximum likelihood and some existing robust estimators. The results are illustrated depending on a simulation study and real datasets.?The new estimators showed the best performance relative to other estimators.

关键词： Logistic Regression Maximum Likelihood Estimator Robust Estimation Outlier Weighted Maximum Likelihood

Use of Vehicle Power-Train Simulation with AMT for Fuel Economy and Performance

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Modern Mechanical Engineering 2013年第3期3卷 127-135页

作者： nagwa ahmed Abdel-Halim Automotive Engineering Department Faculty of Engineering Helwan University Cairo Egypt

Frequent stops and starts for the traffic lights as well as acceleration/deceleration, rather than at constant speed, are the most common transient operating conditions. Consequently, understanding the dynamic characteristics of the powertrain system is vitally important in designing an efficient and fresh vehicle. To investigate the dynamic characteristics of the road vehicle performance, apart from a real road testing, it is necessary to set up a numerical test bed for dynamic performance simulation. The latter is even more convenient, costless and data repeatable. However, the aim of the present paper is to establish a computer simulation package by which the road vehicle power-train system design is developed for a small passenger vehicle based on fuel economy and performance. Furthermore, a proposed professional computer program of Automated Manual Transmission (AMT) system related to organizer algorithm of attractive gearshift requests is also introduced. The result of the proposed AMT ensures that the drive wheels force balance in order to keep gear shift, to kick down or up not only shift feel? but also the fuel consumption, and to alarm by near a specific failure or to get back system performance.

关键词： Automated Manual Transmission (AMT) Dynamic Characteristics Dynamic Performance Simulation Fuel Economy

Efficient Information Set Decoding Based on Genetic Algorithms

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International Journal of Communications, Network and System Sciences 2012年第7期5卷 423-429页

作者： ahmed Azouaoui idriss Chana Mostafa Belkasmi SIME Lab. ENSIAS Mohammed V-Souissi University Rabat Morocco

In this paper, we describe a hard-decision decoding technique based on Genetic Algorithms (HDGA), which is applicable to the general case of error correcting codes where the only known structure is given by the generating matrix G. Then we present a new soft-decision decoding based on HDGA and the Chase algorithm (SDGA). The performance of some binary and non-binary Linear Block Codes are given for HDGA and SDGA over Gaussian and Rayleigh channels. The performances show that the HDGA decoder has the same performances as the Berlekamp-Massey Algorithm (BMA) in various transmission channels. On the other hand, the performances of SDGA are equivalent to soft-decision decoding using Chase algorithm and BMA (Chase-BMA). The complexity of decoders proposed is also discussed and compared to those of other decoders.

关键词： Genetic Algorithms (GA) Error Correcting Codes RS Codes Information Set Decoding Chase Algorithm

Numerical Taxonomic Study of Some Tribes of Gramineae from Egypt

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American Journal of Plant Sciences 2011年第1期2卷 1-14页

作者： ahmed Osman Mohammed Zaki Sohar Hamed nagwa Hussein 不详

A systematic study for eleven tribes of Gramineae surveyed 34 characters including fruit morphology, fruit anatomy and palynology. The results were conducted to some numerical analysis aspects. On the basis of UPGMA (Unpaired Group Method of Average) clustering and PCA (Principal component analysis), the results show congruence between the UPGMA clustering and PCA method, in suggesting two major clads/groups and five subclads.

关键词： Gramineae Numerical Taxonomy UPGMA Cladistic Tree

A Simulation Study on Comparing General Class of Semiparametric Transformation Models for Survival Outcome with Time-Varying Coefficients and Covariates

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Open Journal of Statistics 2019年第2期9卷 169-180页

作者： Yemane Hailu Fissuh Tsegay Giday Woldu idriss Abdelmajid idriss ahmed Abebe Zewdie Kebebe Department of Statistics College of Applied Sciences Beijing University of Technology Beijing China Department of Statistics College of Natural and Computational Sciences Aksum University Aksum Ethiopia Department of Mathematics College of Applied Sciences Beijing University of Technology Beijing China School of Software Engineering Faculty of Information Technology Beijing University of Technology Beijing China

The consideration of the time-varying covariate and time-varying coefficient effect in survival models are plausible and robust techniques. Such kind of analysis can be carried out with a general class of semiparametric transformation models. The aim of this article is to develop modified estimating equations under semiparametric transformation models of survival time with time-varying coefficient effect and time-varying continuous covariates. For this, it is important to organize the data in a counting process style and transform the time with standard transformation classes which shall be applied in this article. In the situation when the effect of coefficient and covariates change over time, the widely used maximum likelihood estimation method becomes more complex and burdensome in estimating consistent estimates. To overcome this problem, alternatively, the modified estimating equations were applied to estimate the unknown parameters and unspecified monotone transformation functions. The estimating equations were modified to incorporate the time-varying effect in both coefficient and covariates. The performance of the proposed methods is tested through a simulation study. To sum up the study, the effect of possibly time-varying covariates and time-varying coefficients was evaluated in some special cases of semiparametric transformation models. Finally, the results have shown that the role of the time-varying covariate in the semiparametric transformation models was plausible and credible.

关键词： Estimating Equation Semiparametric Transformation Models Time-to-Event Outcomes Time-Varying Coefficients Time-Varying Covariate

Phytochemical and biological studies of Butia capitata *** cultivated in Egypt

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Asian Pacific Journal of Tropical Biomedicine 2014年第6期4卷 456-462页

作者： nagwa Mohamed Ammar Mohammed Said Hefnawy Sahar Youssef Al-Okbi Doha Abdou Mohamed Nabil Khamis El-Sayed Amira ahmed El-Anssary Tom Mabry Pharmacognosy Department National Research Centre Pharmacognosy Department Faculty of PharmacyCairo University Food Sciences and Nutrition Department National Research Centre Tanning Materials and Protein Chemistry National Research Centre Molecular Cell and Developmental Biology The School of Biological ScienceBotany DepartmentTaxas State University

Objective:To study the antioxidant and anti-inflammatory activity of Butia capitata(***)leaf extracts along with phytochemical analysis of the proposed bioactive ***:Different successive extracts of *** *** were prepared with selective organic solvents and screened for their anti-inflammatory activities in tested animals and invitro antioxidant *** extensive phytochemical investigation of the bioactive extracts through paper chromatography,thin layer chromatography,column chromatography,gasliquid chromatography(GLC),high pressure liquid chromatography and spectral ***,ultraviolet,hydrogen and carbon nuclear magnetic resonance,electron ionization-mass spectrometry,heteronuclear multiple bond correlation and heteronuclear multiple quantum correlation were carried out Results:Results showed that different extracts possess promising antioxidant effect and significant anti-inflammatory activity with variable *** results of the phytochemical investigation of the bioactive extracts revealed the presence of volatile substances,lipoidal matter,α-tocopherol,free sugars,polysaccharides and flavonoidal ***:*** leaf extracts were shown to possess variable antioxidant effect,the most promising was methanol extract Both polar and non polar extracts were proved to have anti-inflammatory activity,the non polar extract was superior in this respect The bioactivity of the extracts was ascribed to the presence of flavonoids,sterols andα-tocopherol.

关键词： Butia capitata leaves antioxidant effect anti-inflammatory activity bioactive constituents rats.

Urethral Stone: A Rare Cause of Acute Retention of Urine in Men

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Open Journal of Urology 2020年第5期10卷 145-151页

作者： ahmed Ibrahimi idriss Ziani Jihad Lakssir Hachem El Sayegh Lounis Benslimane Yassine Nouini Department of Urology A Ibn Sina University Hospital Faculty of Medicine and Pharmacy Mohammed V University Rabat Morocco

Urethral stones are a very rare form of urolithiasis, they most often originate from the upper urinary tract or bladder, and are rarely formed primarily in the urethra, it is formed on a urethral anatomical pathology in the majority of cases. The clinical symptomatology is very variable ranging from simple dysuria with penile pain to acute retention of urine. Smaller stones can be expelled spontaneously without intervention, but larger stones or complicated stones or those developed on an underlying urethral anatomical pathology require surgical treatment. The minimally invasive treatment should be the preferred route for the surgical treatment of this disease when feasible. We report the case of a young man with no particular pathological history who presented to the emergency department for acute retention of urine secondary to a primary fossa navicularis calculus, through this case, we discuss the different clinical aspects, etiology, pathogenesis, diagnosis and therapy of urethral stone in men.

关键词： Urethral Stone Meatotomy Acute Urinary Retention Penis