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Chinese Journal of Chemistry 2012年第3期30卷 547-556页

作者： Issa,Raafat Mostafa Gaber,Mohammed Al-Wakiel,Nadia Abd-Elhamed fathalla,shaimaa kamal Chemistry Department Faculty of ScienceTanta University31527 TantaEgypt

Mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ） and Cu（Ⅱ） complexes of 5-mercapto-1,2,4-triazol-3-imine-2＇-hydroxynaphthaline have been synthesized and characterized by elemental analysis, IR, IH NMR, EI-mass, UV-Vis, and ESR （electron spin resonance） spectra, molar conductance, magnetic moment measurements, DC conductivity and thermogravimetric analysis. IR spectra confirm that the ligand molecule existed in both thione and thiole forms. The molar conduc- tance values indicate the complexes are nonelectrolyte. The magnetic moment values of the complexes display paramagnetic behavior. All studies confirm the formation of an octahedral geometry for complex 1 and the other complexes have tetrahedral geometrical structures. The structures of the complexes have also been theoretically studied by using the molecular mechanic calculations by the hyperchem. 8.03 molecular modeling program which confirm the proposed structures. The Schiff-base ligand and its metal complexes have also been screened for their antimicrobial activities.

关键词： inorganic chemistry spectral thermal biological studies conductance triazole Schiffbase

Efficient Channel Estimation Techniques for MIMO Systems with 1-Bit ADC

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China Communications 2020年第5期17卷 50-64页

作者： Hany SHussein shaimaa Hussein Ehab Mahmoud Mohamed Electrical Engineering Dept. College of EngineeringKing Khalid UniversityAbha 61411King of Saudi Arabia Electrical Engineering Dept. Faculty of EngineeringAswan UniversityAswan 81542Egypt Electrical Engineering Dept. College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir 11991King of Saudi Arabia

With a low resolution 1-bit ADC on its receiver(RX) side, MIMO with 1-bit ADC took a considerable step in the fulfillment of the hardware complexity constrains of the internet of things(IoT) PHY layer design. However, applying 1-bit ADC at MIMO RX results in severe nonlinear quantization error. By which, almost all received signal amplitude information is completely distorted. Thus, MIMO channel estimation is considered as a major barrier towards practical realization of 1-bit ADC MIMO system. In this paper, two efficient sparsity-based channel estimation techniques are proposed for 1-bit ADC MIMO systems, namely the low complexity sparsity-based channel estimation(LCSCE), and the iterative adaptive sparsity channel estimation(IASCE). In these techniques, the sparsity of the 1-bit ADC MIMO channel is exploited to propose a new adaptive and iterative compressive sensing(CS) recovery algorithm to handle the 1-bit ADC quantization effect. The proposed algorithms are tested with the state-of-the-art 1-bit ADC MIMO constant envelope modulation(MIMO-CEM). The 1-bit ADC MIMO-CEM system is chosen as it fulfills both energy and hardware complexity constraints of the IoT PHY layer. Simulation results reveal the high effectiveness of the proposed algorithms in terms of spectral efficiency(SE) and computational complexity. The proposed LCSCE reduces the computational complexity of the 1-bit ADC MIMO-CEM channel estimation by 86%, while the IASCE reduces it by 96% compared to the recent techniques of MIMO-CEM channel estimation. Moreover, the proposed LCSCE and IASCE improve the spectrum efficiency by 76 % and 73 %, respectively, compared to the recent techniques.

关键词： channel estimation 1-bit ADC MIMO sparsity recovery compressive sensing Internet of things

Effect of supplementing layer hen diet with phytogenic feed additives on laying performance, egg quality, egg lipid peroxidation and blood biochemical constituents

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Animal Nutrition 2018年第4期4卷 394-400页

作者： Reham Abou-Elkhair shaimaa Selim Eman Hussein Department of Nutrition and Clinical Nutrition Faculty of Veterinary Medicine University of Sadat City Department of Nutrition and Clinical Nutrition Faculty of Veterinary Medicine University of Menoufia Department of Poultry Production Faculty of Agriculture University of Menoufia

This study was conducted to evaluate the effects of supplementing laying hen diet with phytogenic additives on laying performance, egg quality, blood constituents and egg lipid peroxidation. Two hundred Lohmann Brown Lite laying hens were randomly allotted to 4 dietary treatments: control(without phytogenic additive), fennel seeds(5 g/kg), black cumin seeds(5 g/kg) and hot red pepper(5 g/kg).Each of the 4 diets was fed to 5 replicates of 10 hens for 8 weeks. No significant differences were observed in body weight or feed intake between the groups. Dietary inclusion of fennel followed by red pepper improved(P < 0.05) egg weight, egg production, egg mass and feed conversion ratio compared with control. Higher yolk shape index, shell and albumen weight percentages and Haugh unit(P < 0.05)were recorded in the fennel supplemented group compared with control. The egg yolk color score increased by the addition of fennel or hot red pepper in laying hen diets compared with control. The inclusion of black cumin or hot red pepper decreased serum and egg yolk cholesterol and malondialdehyde concentrations(P < 0.05) compared with control. Serum aspartate aminotransferase concentration was lower in black cumin group(P < 0.05) than in other treatments. In conclusion, the best laying performance and egg quality were obtained by dietary inclusion of fennel, followed by hot red pepper and black cumin. Dietary supplementation of black cumin or red pepper may lead to the development of low-cholesterol concentration and better antioxidant capacity of eggs.

关键词： Phytogenic additives Egg quality Hepatoprotective activity Lipid peroxidation Cholesterol Laying hens

Eco friendly adsorbents for removal of phenol from aqueous solution employing nanoparticle zero-valent iron synthesized from modified green tea bio-waste and supported on silty clay

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Chinese Journal of Chemical Engineering 2021年第8期34卷 19-28页

作者： shaimaa T.Kadhum Ghayda Yassen Alkindi Talib M.Albayati Department of Civil Engineering University of Technology52 Alsinaa St.BaghdadPO Box 35010Iraq Department of Chemical Engineering University of Technology52 Alsinaa St.Baghdad 35010Iraq

The present research investigated a novel route for the synthesis of nanoparticle zero-valent iron(NZVI)utilizing an aqueous extract of green tea waste as a reductant with ferric ***,the supported nanoparticle zerovalent iron was synthesized using natural silty clay as a support material(SC-NZVI).The NZVI and SC-NZVI were characterized by infrared spectroscopy(FTIR),scanning electron microscope(SEM),X-ray diffraction(XRD),Brunauer–Emmett–Teller(BET),and zeta potential(ζ).The interpretation of the results demonstrated that the polyphenol and other antioxidants in green tea waste can be used as reduction and capping agents in NZVI synthesis,with silty clay an adequate ***,the experiments were carried out to explore phenol adsorption by NZVI and *** determine the optimum conditions,the impact of diverse experimental factors(i.e.,initial pH,adsorbent dose,temperature,and concentration of phenol)was ***,Freundlich,and Tempkin isotherms were used as representatives of adsorption *** obtained results indicated that the adsorption processes for both NZVI and SC-NZVI well fitted by the Freundlich isotherm *** appropriateness of pseudofirstorder and pseudosecondorder kinetics was *** experimental kinetics data were good explained by the second-order *** thermodynamic parameters(ΔH0,ΔS0,andΔG0)for NZVI and SC-NZVI were *** maximum removal rates of phenol at optimum conditions,when adsorbed onto NZVI and SC-NZVI,were found to be 94.8%and 90.1%,respectively.

关键词： Wastewater treatment Environment Nano zero-valent iron Silty clay Phenol Adsorption

Petrology and Geochemistry of Some Ophiolitic Metaperidotites from the Eastern Desert of Egypt:Insights into Geodynamic Evolution and Metasomatic Processes

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1139-1157页

作者： Abdel-Aal M.ABDEL-KARIM Mokhles K.AZER shaimaa A.EL-SHAFEI Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geological Sciences Department National Research Centre12622-DokkiCairoEgypt

Ophiolitic peridotites exposed in the Eastern Desert(ED)of Egypt record multiple stages of evolution,including different degrees of partial melting and melt extraction,serpentinization,carbonatization and *** present study deals with metaperidotites at two selected localities in the central and southern ED,namely Wadi El-Nabáand Wadi Ghadir,*** represent residual mantle sections of a Neoproterozoic dismembered ophiolite that tectonically emplaced over a volcano-sedimentary succession that represents island–arc *** studied metaperidotites are serpentinized,with the development of talc-carbonate and quartz-carbonate rocks,especially along shear and fault *** relics of primary minerals(olivine,orthopyroxene and Cr-spinel)are preserved in a few samples of partiallyserpentinized *** of the Cr-spinel crystals have fresh cores followed by outer zones of ferritchromite and Crmagnetite,which indicates that melt extraction from the mantle protolith took place under oxidizing *** protoliths of the studied metaperidotites were dominated by harzburgites,which is supported by the abundance of mesh and bastite textures in addition to some evidence from mineral and whole-rock chemical *** high Cr#(0.62–0.69;Av.0.66)and low TiO_(2)(<0.3 wt%)contents of the fresh Cr-spinels,the higher Fo(89–92;Av.91)and NiO(0.24–0.54 wt%,Av.0.40)contents of the primary olivine relics,together with the high Mg#(0.91–0.93;Av.91)and low CaO,Al2 O3 and TiO_(2)of the orthopyroxene relics,are all comparable with depleted to highly depleted forearc harzburgite from a suprasubduction zone *** investigated peridotites have suffered subsequent phases of metasomatism,from oceanfloor hydrothermal alteration(serpentinization)to magmatic hydrothermal *** enrichment of the studied samples in light rare earth elements(LREEs)relative to the heavy ones(HREEs)is attributed to most probably be due to the contamination

关键词： ophiolitic metaperidotites partial melting melt extraction geodynamic evolution Eastern Desert Egypt

Phosphoric Acid Pretreatment and Saccharification of Paper Sludge as a Renewable Material for Cellulosic Fibers

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Journal of Renewable Materials 2024年第9期12卷 1573-1591页

作者： Samar El-Mekkawi Wafaa Abou-Elseoud shaimaa Fadel Enas Hassan Mohammad Hassan Chemical Engineering and Pilot Plant Department National Research CentreDokkiGiza12622Egypt Cellulose and Paper Department National Research CentreDokkiGiza12622Egypt

Recycling of paper sludge waste is crucial for establishing a sustainable green *** waste contains valuable sugars that can be converted into important chemicals such as ethanol,poly hydroxybutyrate,and lactic ***,the main challenge in obtaining sugars in high yield from paper sludge is the high crystallinity of cellulose,which hinders *** address this,pretreatment using phosphoric acid was optimized using response surface methodology to facilitate cellulose hydrolysis with minimal energy and *** created prediction model using the response surface method considered factors such as acid concentration(ranging from 60%to 85%),consistency(ranging from 4%to 10%),temperature(ranging from 25℃to 80℃),and time(ranging from 0.5 to 4 h).The results revealed that the model’s significant factors affecting the yield were acid concentration,reaction time,temperature,and the product of acid concentration and temperature,while the model’s significant factors affecting the crystallinity were the consistency,the temperature,and their *** results showed that the optimum conditions for pretreatment were using an acid concentration of 64%,temperature of 25℃,consistency of 10%,and time of 30 *** hydrolysis of the conditionally pretreated paper sludge resulted in a weight loss of 42%,compared to only 18%weight loss in non-pretreated paper ***,the optimized conditions led to low levels of furfurals and acetic acid,which are undesirable by-products that can interfere with sugar *** total sugar obtained under the optimized conditions was 0.43 g glucose/g sample(10.46 g/L),while the contents of methyl furfural,furfural,and acetic acid were 21.65,235.7,and 4.57 mg/L,*** study demonstrates the potential of phosphoric acid for pretreatment and hydrolysis of paper sludge,enabling efficient saccharification and the production of sugars with minimal undesired by-products.

关键词： Waste valorization fermentable sugars response surface methodology acid hydrolysis cellulose crystallinity

Risk Factors Associated with Cholelithiasis during Pregnancy and Postpartum

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Open Journal of Obstetrics and Gynecology 2022年第11期12卷 1166-1175页

作者： shaimaa Belal Hesham Mohammed Hamed Abdelrahman kamal Manal Abdel-Wanees Al-Sayed Hany Mahmoud Abd El Hamid Department of Obstetrics and Gynecology Faculty of Medicine Helwan University Helwan Egypt Department of Obstetrics and Gynecology El-Sahel Teaching Hospital Cairo Egypt Department of General Surgery Sahel Teaching Hospital Cairo Egypt

Gallbladder disease is the most common non-obstetrical cause of maternal hospitalization in the first year postpartum. Many risk factors have been associated with gallbladder disease in pregnancy including body mass index, prenatal weight gain, prenatal physical activity, dietary fat, age, parity, a history of gallbladder disease and the number of previous pregnancies were significant factors related to new gallstones and biliary sludge formation in the pregnant group. The aim of this study is to evaluate the risk factors for gallstones formation in pregnancy and one year after labour. The study included 328 female patients (pregnant or postpartum) divided into two groups;patient group (164 patient) that are pregnant or postpartum patient have gallstones and control group (164 patient) that are pregnant or postpartum patient does not have gallstones. All patients were subjected to full history taking;especially about risk factors predisposing for gallstones, physical examination and pre-operative routine laboratory investigations and imaging as abdominal ultrasound study (U/S). Obesity, young age, history of gallbladder disease and use of estrogen and progesterone are the main risk factors that increase incidence of gallstones during pregnancy or one year postpartum. Use of vit C, iron, drinking coffee and practicing regular physical activity are considered protective factors.

关键词： Cholelithiasis Pregnancy Postpartum

Type 2 diabetes and thyroid cancer:Synergized risk with rising air pollution

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World Journal of Diabetes 2023年第7期14卷 1037-1048页

作者： Eva M Kruger shaimaa A Shehata Eman A Toraih Ahmed A Abdelghany Manal S Fawzy School of Medicine Tulane UniversityNew OrleansLA 70112United States Department of Forensic Medicine and Clinical Toxicology Faculty of MedicineSuez Canal UniversityIsmailia 41522Egypt Division of Endocrine and Oncologic Surgery Department of SurgerySchool of MedicineTulane UniversityNew OrleansLA 70112United States Genetics Unit Department of Histology and Cell BiologyFaculty of MedicineSuez Canal UniversityIsmailia 41522Egypt Department of Ophthalmology Faculty of MedicineSuez Canal UniversityIsmailia 41522Egypt Department of Medical Biochemistry and Molecular Biology Faculty of MedicineSuez Canal UniversityIsmailia 41522Egypt Department of Biochemistry Faculty of MedicineNorthern Border UniversityArar 1321Saudi Arabia

Diabetes is a complex condition,and the causes are still not fully ***,a growing body of evidence suggests that exposure to air pollution could be linked to an increased risk of ***,exposure to certain pollutants,such as particulate Matter and Ozone,has been associated with higher rates of *** the same time,air pollution has also been linked to an increased risk of thyroid *** there is less evidence linking air pollution to thyroid cancer than to diabetes,it is clear that air pollution could have severe implications for thyroid *** pollution could increase the risk of diabetes and thyroid cancer through several *** example,air pollution could increase inflammation in the body,which is linked to an increased risk of diabetes and thyroid *** pollution could also increase oxidative stress,which is linked to an increased risk of diabetes and thyroid ***,air pollution could increase the risk of diabetes and thyroid cancer by affecting the endocrine *** review explores the link between diabetes and air pollution on thyroid *** will discuss the evidence for an association between air pollution exposure and diabetes and thyroid cancer,as well as the potential implications of air pollution for thyroid *** the connections between diabetes,air pollution,and thyroid cancer,it is essential to take preventive measures to reduce the risk of developing the condition.

关键词： Air pollution Diabetes mellitus Health risk Thyroid cancer Thyroid disorders

Ki-67 as a prognostic marker according to breast cancer molecular subtype

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Cancer Biology & Medicine 2016年第4期13卷 496-504页

作者： Nahed A.Soliman shaimaa M.Yussif Department of Pathology Faculty of Medicine University of Helwan Department of Pathology Faculty of Medicine University of Mansoura

Objective: Ki-67 plays an important function in cell division, but its exact role is still unknown. Moreover, few works regarding its overall function were published. The present study evaluated the clinical significance of Ki-67 index as a prognostic marker and predictor of recurrence in different molecular subtypes of breast cancer. The relationship of Ki-67 index with different clinicopathological factors was also ***: Ki-67 index was measured in 107 cases of primary breast cancer from 2010-2012. These patients were evaluated for estrogen receptor, progesterone receptor, and HER2. Ki-67 was divided according to percentage levels: 15%. Followup ranged from 32 months up to 6 ***: Approximately 44, 23, 15, and 25 cases were grouped as luminal A, luminal B, HER2 subtype, and triple-negative(TN),respectively. No luminal A patients showed Ki-67 level higher than 15%, and their recurrence was 20%. In luminal B group, Ki-67 level higher than 15% was observed in 69% of patients, and recurrence was 39%. In HER2 subtype, Ki-67 was higher than 15% in34% of cases, and recurrence was 40%. In triple-negative cases, Ki-67 was higher than 15% in 60% of cases, and recurrence was detected in 32% of patients. Patients with Ki-67 less than 15% displayed better overall survival than those with Ki-67 higher than15%(P = 0.01). Patients with Ki-67 higher than 15% exhibited higher incidence of metastasis and recurrence than those with Ki-67 less than 15%(P = 0.000).Conclusions: Ki-67 may be considered as a valuable biomarker in breast cancer patients.

关键词： Ki-67 prognostic molecular subtypes breast cancer

Bio-Inspired Computational Methods for the Polio Virus Epidemic Model

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Computers, Materials & Continua 2022年第8期72卷 2357-2374页

作者： Fatimah Abdulrahman Alrawajeh F.M.Allehiany Ali Raza shaimaa A.M.Abdelmohsen Tahir Nawaz Cheema Muhammad Rafiq Muhammad Mohsin Department of Mathematics Faculty of Science CollegeImam Abdulrahman Bin Faisal University(IAU)Dammam31441Saudi Arabia Department of Mathematical Sciences College of Applied SciencesUmm Al-Qura UniversityP.O.Box 715Makkah21955Saudi Arabia Department of Mathematics Govt.Maulana Zafar Ali Khan Graduate College Wazirabad52000Punjab Higher Education Department(PHED)Lahore54000Pakistan Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityRiyadh 11671Saudi Arabia Department of Mathematics University of GujratGujrat50700Pakistan Department of Mathematics Faculty of SciencesUniversity of Central PunjabLahore54600Pakistan Department of Mathematics Technische Universitat Chemnitz6209111Germany

In 2021,most of the developing countries are fighting polio,and parents are concerned with the disabling of their *** transmits from person to person,which can infect the spinal cord,and paralyzes the parts of the body within a matter of *** to the World Health Organization(WHO),18 million currently healthy people could have been paralyzed by the virus during 1988–*** all countries but Pakistan,Afghanistan,and a fewmore have been declared *** mathematical modeling of poliovirus is studied in the population by categorizing it as susceptible individuals(S),exposed individuals(E),infected individuals(I),and recovered individuals(R).In this study,we study the fundamental properties such as positivity and boundedness of the *** also rigorously study the model’s stability and equilibria with or without *** numerical study,we design the Euler,Runge–Kutta,and nonstandard finite difference ***,the standard techniques are time-dependent and fail to present the results for an extended *** nonstandard finite difference method works well to study disease dynamics for a long time without any ***,the results of different methods are compared to prove their effectiveness.

关键词： Poliovirus modeling stability results computational methods