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Comparison of bacterial community structures in two systems of a sewage treatment plant using PCR-DGGE analysis

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Journal of Environmental Sciences 2011年第12期23卷 2049-2054页

作者： abd el-Latif hesham Rong Qi Min Yang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Genetics Department Faculty of Agriculture Assiut University Assiut Egypt

The combination of PCR amplification of 16S rRNA genes with denaturing gradient gel electrophoresis （DGGE） analysis was used to reveal the compositions and dynamics of bacterial communities in a sewage treatment plant with two systems, i.e., an anoxic- anaerobic-aerobic system （inverted A2O） and an anaerobic-anoxic-aerobic one （conventional A2O） over a period from February to July 2009, during which both systems experienced serious sludge bulking problems. The DGGE patterns showed that there were many common bands in both systems, suggesting the high similarity of bacterial communities of the two systems. Meanwhile, the moving window correlation analysis showed that the two systems experienced different microbial community structure changes during the period, which might be related with the different situations of the occurrence and disappearance of sludge bulking, as being reflected by sludge volume index （SVI） values. Major bands of DGGE patterns of sludge samples were further sequenced. Phylogenetic affiliation indicated that the majority of the sequences obtained were affiliated with Actinobacteria, Firmicutes, Bacteroidetes/Chlorobi group and α- and β-Proteobacteria. Two sequences showed high similarities to typical filamentous bacteria Microthrix parvicella and Nostocoida limicola I, indicating that these bacterial species have been involved in the sludge bulking problems.

关键词： PCR-DGGE bacterial community activated sludge sludge bulking sewage treatment plant

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

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

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

Nano-crystallites Imine-based Copper(II) Complexes as Mimetics for Copper Oxidase Proteins: Synthesis,Characterization,DFT and Oxidase Mimicking Activity

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Chemical Research in Chinese Universities 2024年第6期40卷 1068-1081页

作者： ALHADHRAMI abdulrahman RAMADAN abd el-Motaleb FATHY ahmed Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Chemistry Department Faculty of ScienceKafr El-Sheikh UniversityKafr El-SheikhEgypt Chemistry Department Faculty of ScienceZagazig UniversityZagazigEgypt

Three tridentate imine ligands containing N2S donors were synthesized via Schiff condensation between derivatives of both amino triazine and 2-carbonyl *** reaction of these ligands with CuCl2 in a molar ratio of 1:1 provides three Cu(II) complexes with the general formula [CuLn·Cl_(2)].Analytical,electrical,magnetic,and spectroscopic studies were used to assign the molecular formulae of these metallic *** function theory (DFT) calculations confirmed the structural analysis results obtained from spectroscopic *** various characterization techniques used demonstrated the penta-coordinated slightly distorted square pyramidal structure for the present Cu(II) complexes 1,2,and *** of cyclic voltammetry were done in methanol to define the electrochemical behavior of the current Cu(II) *** biomimetics of catechol oxidase (C.O.);phenoxazinone synthase (PHS) have been studied in the aerobic oxidation of some phenolic substrates,such as 3,5-di-tert-butylcatechol (3,5-DTBCH2);ortho-aminophenol (o-APH3).The three candidate oxidase mimetics showed promising activity in the order 3 > 1 > *** catalytic activity related to the structural properties of existing oxidase mimetics was *** driving force (-ΔG°) controlling the redox reactions of the present biomolecules was calculated from the redox data of Cu(II) complexes 1,2,and *** potential catalytic reaction pathway for the oxidation of the studied phenolic substrates was discussed.

关键词： Nano-crystallite Imine-based copper(II)complex Mimetics of copper oxidase protein Synthesis and characterization Density function theory(DFT)calculation

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

Permutation-substitution image encryption scheme based on a modified chaotic map in transform domain

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Journal of Central South University 2017年第9期24卷 2049-2057页

作者： Ramadan Noha ahmed Hossameldin H el-khamy Said E abd el-Samie Fathi E Faculty of electronic Engineering Menofia University Faculty of Engineering Alexandria University

A new chaotic image encryption scheme based on permutation and substitution in the Fourier domain is *** Fourier Transform(FRFT)is used before the encryption scheme to get a large degree of *** permutation is achieved by Baker map and the substitution by a key-related-to-plain-image algorithm based on the modified Logistic *** of the Logistic map is developed to increase the space of the encryption key,and hence increase the *** key of the encryption algorithm dependents on the plain image,and thus,the cipher image is sensitive to both the initial key and the plain image to resist known-plaintext and chosen plaintext *** key space is large and hence the algorithm can effectively resist brute-force *** proposed scheme is examined using different performance evaluation metrics and the results prove that the proposed scheme is highly secure,and it can effectively resist different attacks.

关键词： Backer map chaotic encryption fractional Fourier transform (FRFT) modified Logistic map

Efficacy of octreotide in the prevention of complications after pancreaticoduodenectomy in patients with soft pancreas and non-dilated pancreatic duct: A prospective randomized trial

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Hepatobiliary & Pancreatic Diseases International 2018年第1期17卷 59-63页

作者： Ayman el Nakeeb ahmed el Gawalby Mahmoud A.Ali ahmed Shehta Hosam Hamed Mohamed el Refea ahmed Moneer ahmed abd el Rafee Gastroenterology Surgical Center Mansoura University

Background: The efficacy of octreotide to prevent postoperative pancreatic fistula(POPF) of pancreaticoduodenectomy(PD) is still controversial. This study aimed to evaluate the effect of postoperative use of octreotide on the outcomes after ***: This is a prospective randomized controlled trial for postoperative use of octreotide in patients undergoing PD. Patients with soft pancreas and pancreatic duct elayed gastric emptying(P = 0.472), and early postoperative mortality(P = 0.727).Conclusions: Octreotide did not reduce postoperative morbidities, reoperation and mortality rate. Also, it did not affect the incidence of POPF and its clinically relevant variants.

关键词： Pancreaticoduodenectomy Postoperative pancreatic fistula Octreotide Periampullary tumor

Response of seed yield and fatty acid compositions for some sunflower genotypes to plant spacing and nitrogen fertilization

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Information Processing in Agriculture 2017年第3期4卷 241-252页

作者： Mohamed Ali abd el-Satar Asmaa abd-el-Halime ahmed Tamer Hassan Ali Hassan Oil Crops Research Department Field Crops Research InstituteAgricultural Research Center9 El-Gamaa St.GizaEgypt

A field experiment was conducted at the experiment Farm of Kafr-el-Hamam Research Station,Zagazig,Sharkia Governorate,Agricultural Research Center,Egypt during the two successive summer seasons of 2015 and 2016 to achieve the highest yield and good oil quality of three tested sunflower *** both seasons,the experiment was conducted using the split split plot design in randomized complete block design with three replicates arrangement keeping plant spaces(15,20 and 25 cm apart between hills)in main plots,nitrogen fertilization levels(15,30 and 45 N fad.^-1)in sub plots and sunflower genotypes(Giza 102,Sakha 53 and promising line of L120)in sub sub *** and quality traits were significantly influenced by plant spaces,nitrogen fertilization levels and genotypes as well as interactions in both seasons and their combined *** wider plant spacing of 25 cm seems to be a good compromise between the highest seed yield fad.^-1 and good acid composition of *** increasing of nitrogen fertilization level had a positive reflected on yield and desirable acid composition of *** 53 was ranked in the first order in stem diameter,head diameter,100-seed weight,seed weight plant^-1,flowered late and hence seed yield fad.^-1 as well as seed oil content whereas,Giza 102 characterized with its contained the highest proportion of oleic and linoleic unsaturated fatty *** highest values of head diameter,100-seed weight,seed weight plant^-1 and hence seed yield fad.^-1 as well as the highest proportion of oleic and linoleic unsaturated fatty acids composition were obtained by grown sunflower *** 53 at wider spacing of 25 cm with application of nitrogen fertilization levels of 45 N fad.^-*** and path analyses revealed that 100-seed weight and head diameter had the highest direct and indirect influence on seed weight plant1,at the same time also,oleic acid content and linoleic acid content had the highest direct and indirect effect inf

关键词： Sunflower Plant spacing Nitrogen fertilization Genotypes Seed yield Fatty acids