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Impacts of produced water origin on bacterial community structures of activated sludge

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Journal of Environmental Sciences 2015年第11期27卷 192-199页

作者： Zhenyu Wang Feng Pan abd el-latif hesham Yingxin Gao Yu Zhang Min Yang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Key Laboratory for Microorganisms and Functional Molecules College of Life Science Henan Normal University Genetics Department Faculty of Agriculture Assiut University

The purpose of this study was to reveal how activated sludge communities respond to influent quality and indigenous communities by treating two produced waters from different origins in a batch reactor in succession. The community shift and compositions were investigated using Polymerase Chain Reaction–denaturing gradient gel electrophoresis（PCR–DGGE） and further16 S ribosomal DNA（r DNA） clone library analysis. The abundance of targeted genes for polycyclic aromatic hydrocarbon（PAH） degradation, nah Ac/phn Ac and C12O/C23 O, was tracked to define the metabolic ability of the in situ microbial community by Most Probable Number（MPN） PCR. The biosystem performed almost the same for treatment of both produced waters in terms of removals of chemical oxygen demand（COD） and PAHs. Sludge communities were closely associated with the respective influent bacterial communities（similarity 〉 60%）, while one sludge clone library was dominated by the Betaproteobacteria（38%） and Bacteriodetes（30%）and the other was dominated by Gammaproteobacteria（52%）. This suggested that different influent and water quality have an effect on sludge community compositions. In addition, the existence of catabolic genes in sludge was consistent with the potential for degradation of PAHs in the treatment of both produced waters.

关键词： Polycyclic aromatic hydrocarbons Indigenous community Wastewater treatment Functional gene

Soil enzymatic activities and microbial community structure with different application rates of Cd and Pb

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Journal of Environmental Sciences 2007年第7期19卷 834-840页

作者： KHAN Sardar CAO Qing hesham abd el-latif XIA Yue HE Ji-zheng Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Belting 100085 China. Department of Environmental Sciences University of Peshawar 25120 Peshawar Pakistan

This study focused on the changes of soil microbial diversity and potential inhibitory effects of heavy metals on soil enzymatic activities at different application rates of Cd and/or Pb. The soil used for experiments was collected from Beijing and classified as endoaquepts. Pots containing 500 g of the soil with different Cd and/or Pb application rates were incubated for a period of 0, 2, 9, 12 weeks in a glasshouse and the soil samples were analyzed for individual enzymes, including catalase, alkaline phosphatase and dehydrogenase, and the changes of microbial community structure. Results showed that heavy metals slightly inhibited the enzymatic activities in all the samples spiked with heavy metals. The extent of inhibition increased significantly with increasing level of heavy metals, and varied with the incubation periods. The soil bacterial community structure, as determined by polymerase chain reaction- denaturing gradient gel electrophoresis techniques, was different in the contaminated samples as compared to the control. The highest community change was observed in the samples amended with high level of Cd. Positive correlations were observed among the three enzymatic activities, but negative correlations were found between the amounts of the heavy metals and the enzymatic activities.

关键词： soil contamination heavy metals application rate enzymatic activity microbial community

Effective damping of local low frequency oscillations in power systems integrated with bulk PV generation

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Protection and Control of Modern Power Systems 2021年第1期6卷 512-524页

作者： Ahmed hesham abd el-Kareem Mohamed abd elhameed Mahmoud M.elkholy Operation Engineer at New Capital Power Plant New Capital CityEgypt electrical Power and Machines Department Faculty of EngineeringZagazig UniversityZagazigEgypt

High penetration of renewable sources into conventional power systems results in reduction of system inertia and noticeable low-frequency oscillations (LFOs) in the rotor speed of synchronous generators. In this paper, we propose effective damping of LFOs by incorporating a supplementary damping controller with a photovoltaic (PV) generating station, where the parameters of this controller are coordinated optimally with those of a power system stabilizer (PSS). The proposed method is applied to damp local electromechanical modes by studying a system comprising a synchronous generator and a PV station connected to an infinite bus. The PV station is modeled following the instructions of the Western electricity Coordinating Council. The problem is modeled as an optimization problem, where the damping ratio of the electromechanical modes is designed as the objective function. Constraints including upper and lower limits of decision parameters and damping ratio of other modes are considered by imposing penalties on the objective function. Different optimization algorithms are used to pursue the optimal design, such as political, improved gray wolves and equilibrium optimizers. The results validate the effectiveness of the proposed controller with PSS in damping local modes of oscillations.

关键词： Low frequency oscillations Damping controller PV WECC

Cancelable Speaker Identification System Based on Optical-Like Encryption Algorithms

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Computer Systems Science & Engineering 2022年第10期43卷 87-102页

作者： Safaa el-Gazar Walid el-Shafai Ghada el-Banby hesham F.A.Hamed Gerges M.Salama Mohammed abd-elnaby Fathi E.abd el-Samie Department of electrical Engineering Faculty of EngineeringEgyptian-Russian UniversityCairoEgypt Department of electronics and electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Laboratory Department of Computer SciencePrince Sultan UniversityRiyadh11586Saudi Arabia Department of Industrial electronics and Control Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia

Biometric authentication is a rapidly growing trend that is gaining increasing attention in the last *** achieves safe access to systems using biometrics instead of the traditional *** utilization of a biometric in its original format makes it usable only ***,a cancelable biometric template should be used,so that it can be replaced when it is *** biometrics aims to enhance the security and privacy of biometric *** encryption is an efficient technique to be used in order to generate cancelable biometric *** this paper,a highly-secure encryption algorithm is proposed to ensure secure biometric data in verification *** considered biometric in this paper is the speech *** speech signal is transformed into its ***,the spectrogram is encrypted using two cascaded optical encryption *** first algorithm is the Optical Scanning Holography(OSH)for its efficiency as an encryption *** OSH encrypted spectrogram is encrypted using Double Random Phase Encoding(DRPE)by implementing two Random Phase Masks(RPMs).After the two cascaded optical encryption algorithms,the cancelable template is *** verification is implemented through correlation estimation between enrolled and test templates in their encrypted *** the correlation value is larger than a threshold value,the user is *** threshold value can be determined from the genuine and imposter correlation distribution curves as the midpoint between the two *** implementation of optical encryption is adopted using its software rather than the optical *** efficiency of the proposed cancelable biometric algorithm is illustrated by the simulation *** can improve the biometric data security without deteriorating the recognition *** results give close-to-zero This values for the Equal Error Rate(EER)and close-to-one values for the Area under Receiver Operator Charact

关键词： Cancelable biometrics spectrogram OSH DRPE EER AROC

electrowinning of Copper Using Rotating Cylinder electrode Utilizing Lead Anode

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Engineering（科研） 2011年第4期3卷 340-358页

作者： hesham Soliman Ahmed abd el-Moneim 不详

The effect of lead anode, rotating cylinder electrode (RCE), amount of 1,2-dihydroxypropane (12-DHP), temperature and rotation on the electrowinning of copper from low concentration acidified copper sulphate solution has been investigated. Copper powder was electrodeposited onto RCE that made of pure copper. From cyclic voltammetry experiments, an empirical parameter called the departure percent, S, was obtained which may represent the stability of the organic additive in the given medium and under the experimental conditions. The inhibition percentage, P, was 0.00 - 89.91% depending on the experimental variables. P was affected by temperature and mole fraction of 12-DHP, while rotation did not show any influence on it. Values of activation energy of electrodeposition process, Ea, were found to be less than 28 kJ mol-1 indicating diffusion controlled process. The overall mass transfer correlations under the present conditions have been computed using the dimensional analysis method. The data were valid for 90 electrodeposited copper powder as well as deposits composition and crystallite size have been studied. Various crystallite sizes ranged 7.1 nm - 250.6 nm were obtained and characterized by EDS and XRD. Different topographs proved that the rate of copper electrodeposition increased by increasing deposition time, temperature and the speed of rotation. Also, they proved that the deposition rate decreased by adding 12-DHP to the solution. Therefore, the results obtained by SEM supported those achieved by measuring the limiting current density and follow the normal manner when organic solvents were added to the electrodeposition bath.

关键词： electrodeposition electrowinning Lead Anode Rotating Cylinder electrode (RCE) 1 2-Dihydroxypropane (12-DHP) Copper Powder

Timed Intercourse versus Intrauterine Insemination with Mild Ovarian Stimulation for Unexplained Infertility

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Open Journal of Obstetrics and Gynecology 2022年第12期12卷 1279-1288页

作者： Hany Mahmoud abd el Hamid Manal abdel-Wanees Alsayed hesham Mohammed Hamed Shaimaa Belal Department of Obstetrics and Gynecology El-Sahel Teaching Hospital Cairo Egypt Department of Obstetrics and Gynecology Faculty of Medicine Helwan University Helwan Egypt

Background: Infertility is unexplained in about 22% - 28% of infertile couples. Spontaneous pregnancy may occur in them. If did not happen, Expectant management will be via clomiphene citrate (CC) administration, intrauterine insemination (IUI), and IVF & ICSI. Aim: to assess the effectiveness of intrauterine insemination with mild controlled ovarian stimulation compared with expectant management in couples with unexplained infertility more than one year. Methods: 160 couples with unexplained infertility were selected, The couples were randomly divided into two groups: Group (A) “80 couples”: Intrauterine insemination (IUI) with mild controlled ovarian stimulation (combination of CC + hMG) using prepared semen and was performed 36 hours after hCG injection, Group (B) “80 couples”: Couples had no ovulation induction. They encouraged for timed intercourse in the most fertile days of female cycle guided by folliculometry for 6 months. Data were collected quantitatively, coded and analyzed using SPSS. The power of study is 80% and 95% confidence interval. Result: The pregnancy rate was calculated in both groups: In group (A) (IUI/COS): OPR (Ongoing pregnancy rates) was 27.5% and PR (pregnancy rates)/cycle was 8.6%. In group (B) (Expectant management): OPR was 25% and PR/cycle was 5.3%. Conclusion: Mild controlled ovarian stimulation CC + hMG with IUI offers no statistical significance in terms of pregnancy outcomes over expectant management in this study however significance in the response to stimulation.

关键词： Intrauterine Insemination Ovarian Stimulation Unexplained Infertility

Doppler Study of Uterine Artery and Ultrasonography of Endometrial Thickness in Perimenopausal and Postmenopausal Bleeding

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Open Journal of Obstetrics and Gynecology 2022年第4期12卷 309-322页

作者： Shaimaa Belal Manal abdel-Wanees Al-Sayed Hany Mahmoud abd el Hamid hesham Mohammed Hamed Department of Obstetrics and Gynecology Faculty of Medicine Helwan University Helwan Cairo Egypt Department of Obstetrics and Gynecology Al-Sahel Teaching Hospital Cairo Egypt

Background: Transvaginal color Doppler sonography of the uterine artery has been reported useful for evaluation of abnormal uterine bleeding in peri-/post-menopausal women. It may differentiate physiological from malignant endometrial changes. Objective: Evaluating the endometrial thickness and uterine artery Doppler as an initial diagnostic tool to identify patients with abnormal endometrial pathology. Methods: This is a prospective case control study consisted of total 50 women with peri-(n = 35) and post-(n = 15) menopausal bleeding, with 20 women consisting control group (no bleeding) (peri-(n = 10) and post-menopausal (n = 10)). Double layer endometrial thickness and uterine-artery-Doppler waveforms were measured, with the latter being S/D ratio, RI and PI. These were related to histological findings (endometrial biopsy). Result: Patients with abnormal uterine bleeding (both peri- and postmenopausal) had a significantly higher mean endometrial thickness than the control women. Study group showed a significantly lower value of all Doppler indices (S/D ratio, RI and PI). In study group, patients with malignant endometrial pathology showed significantly thicker endometrium and significantly lower Doppler indices than those with benign pathology. Conclusion: The combination of endometrial thickness and uterine artery color Doppler pattern might predict uterine endometrial malignancy, although whether it can discriminate (screen) patients requiring endometrial biopsy is not evident. Further study is needed.

关键词： Doppler Study Uterine Artery Ultrasonography Endometrial Thickness

Predictors for Dilated Aorta in Repaired and Unrepaired Tetralogy of Fallot

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World Journal of Cardiovascular Diseases 2015年第8期5卷 233-253页

作者： Khaled R. abd el Meguid hesham B. Mahmoud Mostafa M. Mohammad Division of Cardiology Benisuef University Hospital Benisuef Egypt Division of Cardiology National Heart Institute Cairo Egypt

Aortic root pathology has been described in patients with Tetralogy of Fallot, although the most common reason for repeat surgery in the adult after TOF repair relates to problems in the right ventricular outflow tract, the aortic root is often forgotten. Objective: We sought to determine those patients with known Fallot tetrallogy at risk for progressive dilatation of the thoracic aorta and explore the common predictors present in this patient group. Methods and Results: A multicenter observational study which enrolled 100 patients (50 surgically repaired and 50 before surgical repair of TOF) with standardized reassessment of echocardiographic parameters and multislice CT angiography of the heart and great vessels data. The data were reviewed and analyzed according to the demographic, morphological, surgical and clinical details. We used standard nomograms and Z score for aortic root dimensions at the level of aortic annulus, sino-tubular junction and sinus of Valsalva based on body surface area. For surgically repaired patients, all the measured diameters across aortic annulus, STJ & sinus of Valsalva were larger in the dilated unrepaired group with mean & median of 24.63 (3.99) & 25 (15 - 35), 27.2 (4.26) & 27 (17 - 40), 35.97 (4.59) & 36 (24 - 45) mm respectively compared to a mean & median of 13.2 (2.62) & 13 (9 - 17), 14.53 (2.90) & 14 (10 - 19), 20.53 (3.40) & 21 (14 - 25) mm respectively in the not dilated unrepaired group with significant statistical difference (p value ely compared to a mean & median of 13.2 (2.62) & 13

关键词： Tetralogy of Fallot Aortopathy Ventricular Septal Defect Aortic Regurgitation Pulmonary Regurgitation Pulmonary Atresia

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