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Ecological risk assessment of surficial sediment by heavy metals from a submerged archaeology harbor,South Mediterranean Sea,Egypt

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Acta Geochimica 2020年第2期39卷 226-235页

作者： maha Ahmed mohamed abdallah Ahmed mohamed Badr-ElDin Marine Pollution Lab National Institute of Oceanography and FisheriesAlexandriaEgypt Oceanography Department Faculty of ScienceAlexandria UniversityAlexandriaEgypt

A protected semi-enclosed embayment,the Eastern Harbor(EH),is situated in the central sector of the Mediterranean coast of Alexandria,*** is a famous fishing dock and water-sport center and its importance arose after the discovery of the Ptolemaic royal quarter of ancient *** protect this national treasure and improve its environmental health,the untreated anthropogenic effluents,which continued for decades into the EH since 1992,must be totally ***,it is an important issue to continually monitor and asses the environmental status of the *** sediment texture,total organic carbon,and the accumulation,distribution,and ecological risks of Cd,Cr,Pb,As,Hg and A1 were determined with a total of 14 surficial sediments samples collected in the EH during *** contents were compared to the literature data to assess the pollution status of *** factors,Degree of contamination(mCd)and potential ecological risk were calculated as a criterion of possible *** mCd calculation produces an overall average value for a range of pollutants,in the present study the contamination factor that provides a measure of the degree of overall contamination in the surface layers in a particular sampling site may provide a better indication of the state of pollution in the EH sediments than other indicators.

关键词： Heavy metals Eastern harbor Enrichment factors Degree of contamination Potential ecological risk

Ore Controls and Metallogenesis of Au-Ag Deposits at Atalla Mine,Central Eastern Desert of Egypt

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1451-1470页

作者： mohamed abd EL MONSEF Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Institute of Geological Sciences Faculty of ScienceMasaryk UniversityBrnoCzech Republic

Gold-silver deposits in the Atalla area occur as hydrothermal quartz veins in NE–SW pre-existing fractures within the Atalla granitic *** orientation of such quartz veins has been attributed to extensional behavior related to the Atalla Shear Zone(ASZ).The Atalla area is covered by a variety of lithologies that are(from oldest to youngest):metasedimentary rocks,metavolcanic rocks,ophiolite assemblage(serpentinites/talc-carbonates),Atalla granite and Dokhan volcanic ***,Atalla granite ranges in composition from granodiorite to *** geochemistry constrains the calc-alkaine affinity of the Atalla granite that was intruded within an orogenic(syncollision)tectonic *** ore minerals are represented by gold/silver(electrum),pyrite(Py1&Py2),arsenopyrite,pyrrhotite,sphalerite,chalcopyrite,galena,covellite and *** temperature of ore formation ranges from 240 to 285℃and the estimated fluid pressure is in the range of 20–100 *** on the geological setting,ore textures and fluid characteristics;the Atalla Au-Ag deposits are considered to be orogenic in nature,formed from a continental collision(~653-590 Ma),synchronous with the emplacement of calc-alkaline magmatism during the evolutionary history of the Arabian Nubian Shield(ANS).The initial ore-forming fluid was primarily derived from a metamorphic source related to ophiolitic-serpentinite rocks under deep regional conditions of greenschist-amphibolite facies,where the Atalla granitic eruption provided the required temperature conditions for the metamorphic process to take *** such conditions,the transportation of ore metals as bisulfide complexes is *** deposition of ore minerals was triggered by fluidwallrock interaction through fracture pathways in conjunction with a temperature-pressure drop that is likely to have been related to uplift into the crustal levels.

关键词： Gold-silver arsenopyrite geothermometry fluid inclusions orogenic deposits Atalla Shear Zone(ASZ)

Effect of different metal sulfate precursors on structural and catalytic performance of zirconia in dehydration of methanol to dimethyl ether

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燃料化学学报 2018年第1期46卷 67-74页

作者： abd El-Aziz A.Said mohamed abd El-Aal Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt

ZrO_2 was treated with 10% SO_4^(2-) from different metal sulfate precursors for methanol dehydration to dimethyl *** the samples exhibited tetragonal phase and no diffraction peaks corresponding to metal sulfates or metal oxides were *** FT-IR results revealed that there were different interactions between sulfate and ZrO_2,and this had a great effect on the surface area of the *** catalytic activity was measured over the catalysts in the temperature range of 100-300 ℃.The results revealed that sulfated zirconia with CuSO_4·5 H_2O and Al_2(SO_4)_3·16 H_2O showed the best catalytic *** maximum yield of DME ≈87% was obtained over CuSZ at a reaction temperature of 275 ℃.Moreover,the catalytic activity of the catalysts was correlated well with their surface acidity that measured by dehydration of isopropanol.

关键词： MSO 4/ZrO2 甲醇脱水 DME

Determination of a novel ACE inhibitor in the presence of alkaline and oxidative degradation products using smart spectrophotometric and chemometric methods

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Journal of Pharmaceutical Analysis 2014年第2期4卷 132-143页

作者： maha abdel-Monem Hegazy Maya Shaaban Eissa Osama Ibrahim abd El-Sattar mohamed mohamed abd El-Kawy Analytical Chemistry Department Faculty of PharmacyCairo UniversityCairoEgypt Analytical Chemistry Department Faculty of PharmacyEgyptian Russian UniversityCairoEgypt National Organization of Drug Control and Research GizaEgypt

Simple, accurate, sensitive and validated UV spectrophotometric and chemometric methods were developed for the determination of imidapril hydrochloride （IMD） in the presence of both its alkaline （AKN） and oxidative （OXI） degradation products and in its pharmaceutical formulation. Method A is the fourth derivative spectra （D4） which allows the determination of IMD in the presence of both AKN and OXD, in pure form and in tablets by measuring the peak amplitude at 243.0 nm. Methods B, C and D, manipulating ratio spectra, were also developed. Method B is the double divisor-ratio difference spectrophotometric one （DD-RD） by computing the difference between the amplitudes of IMD ratio spectra at 232 and 256.3 nm. Method C is the double divisor-first derivative of ratio spectra method （DD-DR1） at 243.2 nm, while method D is the mean centering of ratio spectra （MCR） at 288.0 nm. Methods A, B, C and D could successfully determine IMD in a concentration range of 4.0-32.0 mg/mL. Methods E and F are principal component regression （PCR） and partial least-squares （PLS）, respectively, for the simultaneous determination of IMD in the presence of both AKN and OXI, in pure form and in its tablets. The developed methods have the advantage of simultaneous determination of the cited components without any pre-treatment. The accuracy, precision and linearity ranges of the developed methods were determined. The results obtained were statistically compared with those of a reported HPLC method, and there was no significant difference between the proposed methods and the reported method regarding both accuracy and precision.

关键词： Double divisor-ratio difference Double divisor-ratio derivative Mean centering of ratio spectra Chemometry Imidapril hydrochloride

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

Immobilization of Co(Ⅱ) Ions in Cement Pastes and Their Effects on the Hydration Characteristics

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Journal of Materials Science & Technology 2011年第1期27卷 74-80页

作者： Eisa Hekal Essam Kishar Wafaa Hegazi maha mohamed Chemistry Department Faculty of ScienceAin Shams University Chemistry Department Women s College for ArtsScience and EducationAin Shams University

The immobilization of Co（Ⅱ） in various cement matrices was investigated by using the solidification/stabilization（S/S） *** different cement pastes used in this study were ordinary Portland cement in absence and presence of water reducing-and water repelling-admixtures as well as blended cement with *** ratios of Co（Ⅱ） were used（0.5% and 1.0% by weight of the solid binder）.The hydration characteristics of the used cement pastes were tested via the determination of the combined water content,phase composition and compressive strength at different time intervals up to 180 *** degree of immobilization of the added heavy metal ions was evaluated by determining the leached ion concentration after time intervals extended up to 180 *** leachability experiments were carried out by using two modes：the static and the semi-dynamic leaching *** was noticed that the concentration of the leached Co2＋ ions in the static mode of leachability was lower than the solubility of its hydroxide in all the investigated cement pastes.

关键词： Hydration characteristic of cement Admixtures Immobilization Heavy metals

Telehealth utilization among Egyptian population and health institutional readiness:An exploratory study

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中西医结合护理杂志(英文) 2023年第3期5卷 188-196页

作者： Basma mohamed OSMAN Maaly Zayed mohamed Shaimaa Ali mohamed ISMAIL Lamiaa Saad abd allah Marwa Mamdouh SHABAN Department of Community Health Nursing Faculty of NursingCairo UniversityCairoEgypt Department of Nursing Administration Faculty of NursingCairo UniversityCairoEgypt

Objective:This study aimed to assess the public’s perspectives and the health institutions’readiness for telehealth utilization in ***:A cross-sectional study design was employed,and data were collected from a convenient sample of 800 Egyptian citizens and 26 nursing administrators and information technology personnel from 16 governmental hospitals and 10 private hospitals between January and March *** Egyptian community utilization of telehealth questionnaire and the telemedicine hospital readiness assessment were used to collect the ***:The results revealed that 35.1%of the general Egyptian population used telehealth services and 43%expressed willingness to use them in *** perceived by the general Egyptian population,the most prevalent barriers to telehealth utilization were communication barriers(97.6%),lack of confidence in health professionals(77.6%),technological limitations(72.5%),the need for physical examination(25%),and privacy concerns(10%).Regarding hospital readiness,42%of governmental hospitals were not taking any initiative to implement telehealth services,and 15.4%were at the beginner level,meaning that some steps had been ***,the hospital was still far from being able to implement telehealth *** contrast,private hospitals were either at the beginner or advanced ***:Although the use of telehealth services in Egypt has increased,there is a need to address the barriers to public utilization and improve hospitals’readiness to implement telehealth services to enhance public usage.

关键词： Attitude barriers hospital readiness public use telehealth nursing practice nursing administration

Magnetoresistive properties of Ni-doped La_(0.7)Sr_(0.3)MnO_3 manganites

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Rare Metals 2016年第7期35卷 551-558页

作者： Ahmed mohamed Ahmed abd El-Moez Ahmed mohamed Medhat abdelrady abdellateef Hassan Ahmed abd El-Ghanny Physics Department Faculty of ScienceSohag University

Lao.7Sr0.3Mnl_xNixO3 （x = 0, 0.025, 0.050 and 0.075） ceramics were prepared by the conventional solid-state reaction method. The partial substitution of Mn by Ni2＋ leads to a decrease in cell volume as well as a structural transition from the rhombohedral to the orthorhombic structure. Ni2＋ doping increases the electrical resistivity, decreases the semiconductor-metal transition temperature （Tms） and relatively enhances the room temperature magnetoresistance （MR）, especially in x = 0.025 and around Tins. With respect to conduction mechanism, the small polaron hopping （SPH） and the variable range hopping （VRH） models were used to ex- amine conduction in the semiconducting region.

关键词： Manganites X-ray diffraction Structure Electrical resistivity Magnetoresistance

Neoproterozoic Tectonic Events of Egypt

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1366-1405页

作者： mohamed abd EL-WAHED Zakaria HAMIMI Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geology Faulty of ScienceBen ha UniversityBenha 13518Egypt

The Egyptian Nubian Shield(ENS)represents the northwestern part of the Arabian-Nubian Shield and the northern extension of the East African *** ENS is regarded as being formed due to northward-directed escape *** is characterized by mild accretion and suture zones dominated by major strike-slip zones with a commonly sinistral sense of movement;some shear zones display a dextral sense of *** is dominated by gneisses and migmatites in the south,arc volcaniclastic metasediments and highly dismembered ophiolites in the central parts,whereas its northern part is dominated by late-to post-tectonic *** southern Sinai,the Neoproterozoic rocks are grouped into four complexes,namely Feiran–Solaf,Sa’al–Zaghra,Kid and *** ENS ophiolites were formed between 730–750 Ma,mainly in a supra-subduction zone *** ENS has undergone a Neoproterozoic deformation history involving three successive phases:(1)Early N–S shortening phase(D1),(2)Syn-accretionary phase(D2)and(3)Post-accretionary phase(D3).The initial island-arc stage(780–730 Ma)is a N–S shortening phase initiated by collision between the Eastern Desert tectonic terrane to the north with both the Gebeit and Gabgaba terranes to the south(830–720 Ma).During the arc-splitting and back-arc spreading stage(730–620),voluminous syn-tectonic granitoids intruded into the ENS(750–610 Ma).The E–W-directed compressional/transpressional phase(620–450 Ma)led to the overall uplift of the central part of the ENS and consequently the development and exhumation of the core complexes in oblique convergent *** E–W intense shortening deformation resulted also in the formation of NW-and NE-striking sinistral and dextral strike-slip shear zones,*** latest periods of the E–W-directed compressional/transpressional regime were characterized by deposition of the molasse-type Hammamat Sediments unconformably over the Dokhan Volcanics,or interbedded with *** combined thrusting,folding and sin

关键词： Neoproterozoic deformation N–S shortening syn-accretionary phase post-accretionary phase Egyptian Nubian Shield