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The dual-function of bioactive peptides derived from oyster (Crassostrea gigas) proteins hydrolysates

Food Science and Human Wellness 2023年第5期12卷 1609-1617页

作者： Dongyang Zhu Zhen Yuan Di Wu Chao Wu hesham r.el-seedi Ming Du School of Food Science and Technology National Engineering Research Center of SeafoodDalian Polytechnic UniversityDalian 116034China Pharmacognosy Group Department of Pharmaceutical BiosciencesUppsala UniversityBiomedical CentreUppsala SE 75124Sweden International research Center for Food Nutrition and Safety Jiangsu UniversityZhenjiang 212013China

Oysters(Crassostrea gigas)have a wide range of functionality due to their nutritional and bioactive components. However, the bioactive peptides of oyster proteins are rarely reported, particularly their antidiabetes effects and antioxidants. Oyster proteins were extracted from fresh oysters using phosphatebuffered saline and simulated gastrointestinal digestion was performed. The degree of hydrolysis(DH), structural characterization, molecular weight(Mw)distribution, free amino acid, anti-diabetic activity, and antioxidant activity were studied during in vitro simulated gastrointestinal digestion. The results showed that the α-glucosidase inhibitory activity, α-amylase inhibitory activity, DPPH radical scavenging activity, and ABTS radical scavenging activity of the oyster protein gastrointestinal digest were increased(P rom 0 to 33.96%, from 9.17% to 44.22%, from 9.01 μg trolox/mg protein to 18.48 μg trolox/mg protein, and from 21.44 μg trolox/mg protein to 56.21 μg trolox/mg protein, respectively. Additionally, the DH, β-turn structure, fluorescence intensity, free amino acid, and short peptide content(Mw reased in the simulated gastrointestinal digestion. These results indicate that the digestive hydrolysates obtained from oyster proteins could be used as natural anti-diabetic and antioxidant agents.

关键词： Oyster proteins Simulated gastrointestinal digestion Anti-diabetic activity Antioxidant activity Free amino acid

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Immunomodulatory effect of ethanol-soluble polypeptides from Atlantic cod (Gadus morhua)

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Food Science and Human Wellness 2023年第4期12卷 1192-1203页

作者： Zhen Yuan Meilian Yang Dongyang Zhu Di Wu Shuzhen Cheng Chao Wu hesham r.el-seedi Ming Du School of Food Science and Technology National Engineering Research Center of SeafoodDalian Polytechnic UniversityDalian 116034China Beijing Advanced Innovation Center for Food Nutrition and Human Health College of Food Science and Nutritional EngineeringChina Agricultural UniversityBeijing 100083China Pharmacognosy Group Department of Medicinal ChemistryUppsala UniversityBiomedical CentreUppsala 75123Sweden

There are many active substances in Atlantic cod(Gadus morhua)explaining the variety of biological *** order to study the immunomodulatory activity and the mechanism of Atlantic cod peptides at the cellular *** this study,cod peptides were isolated by 80%ethanol extraction method,the isolated ethanol-soluble cod peptides(CP-ES)were investigated and their immunomodulatory activity was ***,CP-ES showed lower molecular weight and more hydrophobic amino ***-ES could promote the proliferation of spleen lymphocytes and T lymphocytes in mice,suggesting that CP-ES may regulate adaptive *** promoted the release of NO and the expression of iNOS,TNF-α,IL-6 and IL-1βgenes in macrophages,suggesting that CP-ES may regulate innate ***-ES could promote the expression of TLr2 gene,and the peptides identified in CP-ES were docked with TLr2 to predict the peptides playing a major role in *** results suggested that CP-ES may regulate the immune activity of both innate and adaptive lines.

关键词： Gadus morhua Immunomodulation Peptides TLr2 Molecular docking

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3D finite element analysis of composite noise barrier con- structed of polyurethane products

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Frontiers of Structural and Civil Engineering 2017年第1期11卷 100-110页

作者： Ben DAEE hesham el NAGGAr Department of Civil and Environmental Engineering the University of Western Ontario London ON N6A 5B9 Canada

This paper presents a numerical investigation on the structural performance of an innovative noise barrier consisting of poly-block, rigid polyurethane foam （rPF） and polyurea. The mechanical characteristics of rPF as well as the flexural resistance of the proposed wall system （poly-wall） were established and presented in another study. The experimental results are used in the current study to develop, calibrate and verify 3D finite element （FE） models of the wall system. The components of the poly-wall including steel rebars, poly-blocks and rPF cores were simulated and then verified using the results of experiments conducted on the wall components. The results of numerical analysis exhibited a satisfactory agreement with the experimental outcomes for the entire wall system. The verified numerical models were then used to conduct a parametric study on the performance of poly-wall models under uniform wind load and gravity load. The findings of the current study confirmed that the structural performance of poly-wall is satisfactory for noise barrier application. Simulation techniques for improvement of the numerical analysis of multi-martial 3D FE models were discussed.

关键词： 3D finite element sound wall rigid polyurethane foam poly-wall numerical model calibration

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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 cor.elation 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

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Hydraulic head difference at two sides of suspended waterproof curtain during multi-grade dewatering of excavation

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Underground Space 2023年第3期10卷 137-149页

作者： Tao Yang Li-yuan Tong M.hesham el Naggar Xin Yan School of Transportation Southeast UniversityNanjing 21000China Department of Civil and Environmental Engineering Western UniversityLondon N6A 5B9Canada

This paper proposes an approach to calculate the head difference at two sides of suspended waterproof curtains during multi-grade *** seepage during the dewatering process can be subdivided into three regions:(i)seepage in pit,(ii)seepage between cur-tains,and(iii)seepage outside the *** flow rate of the first region is equal to the pumping rate,and the flow rate of the second and third regions can be obtained by numerical analysis.A numerical model is established to simulate the seepage in the second and third regions and its performance is validated by using the measured data of a series of field *** flow rate of each region is then used to derive formulae for the head difference in conventional dewatering,which can be used to determine the head difference at two sides of each waterproof curtain during multi-grade *** proposed formula expresses the head difference as a function of the relative depth of the curtain inserted into the confined aquifer,the thickness of the aquifer,the distance between two curtains,and the anisotropy of the hydraulic conductivity of the *** proposed numerical approach is further validated by using data derived from numerical *** validation results demonstrated that the predictions of the proposed approach are acceptable and convenient.

关键词： Head difference Multi-grade dewatering Suspended waterproof curtain Confined aquifer

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electrodeposited Ni and Ni-Co alloys using cysteine and conventional ultrasound waves

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Science China Chemistry 2013年第10期56卷 1446-1454页

作者： el-FEKY hesham NEGEM Mosaad rOY Sudipta HelAL Nadia BArAKA A. Chemistry Department Faculty of Science Fayoum UniversityFayoum 63514 Egypt School of Chemical Engineering and Advanced Materials Newcastle University Newcastle upon TyneNE1 7RU United Kingdom Chemistry Department Faculty of Science Cairo UniversityGiza 12613 Egypt

Ni-Co alloys were electroplated from sulphate electrolyte using addition agents including sodium gluconate, boric acid and eysteine on copper foil by the galvanostatic technique and ultrasound waves. The chemical composition, surface morphologies, crystalline structure and hardness of the Ni-Co alloys were studied using energy dispersive spectroscopy, scanning electron microscope, X-ray diffraction and Vickers testing method, respectively. The effect of current density and addition agents on the microstructure and morphology of Ni-Co alloys were examined. The appropriate concentration of additives and ultrasound waves were found to produce fine and smooth crystals leading to higher hardness of Ni-Co alloys. The microhardness of the Ni-Co alloys was varied between 4860-7530 HV. The surface morphology of coatings was changed from granular to fine due to using of gluconate, boric acid, cysteine and ultrasound waves. The mechanical properties of nanocrystalline Ni-Co alloys showed an increase of the hardness with the growing of Ni content in the alloy. The X-ray diffraction studies indicated that nanocrystalline structure was face-centred cubic for pure Ni and Ni-Co alloys with Co content in the range of 1-75 wt.%. A hexagonal closed-package structure was obtained for pure Co and Ni-Co alloys with the cobalt content with range of 75-99 wt.%.

关键词： electrodeposition nanocrystalline Ni alloys ultrasound microhardness

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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 cor.elations were observed among the three enzymatic activities, but negative cor.elations 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

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Numerical modeling of time-dependent deformation and induced stresses in concrete pipes constructed in Queenston shale using micro-tunneling technique

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Journal of rock Mechanics and Geotechnical Engineering 2018年第2期10卷 290-309页

作者： Hayder Mohammed Salim Al-Maamori M.hesham el Naggar Silvana Micic Department of Civil and Environmental Engineering Western University Geotechnical research Center Western University

Effects of time-dependent deformation（TDD） on a tunnel constructed using the micro-tunneling technique in Queenston shale（QS） are investigated employing the finite element method. The TDD and strength parameters of the QS were measured from tests conducted on QS specimens soaked in water and lubricant fluids（LFs） used in micro-tunneling such as bentonite and polymer solutions. The numerical model was verified using the results of TDD tests performed on QS samples, field measurements of some documented projects, and the closed-form solutions to circular tunnels in swelling rock. The verified model was then employed to conduct a parametric study considering important micro-tunneling design parameters, such as depth and diameter of the tunnel, in situ stress ratio（K;）, and the time lapse prior to replacing LFs with permanent cement grout around the tunnel. It was revealed that the time lapse plays a vital role in controlling deformations and associated stresses developed in the tunnel *** critical case of a pipe or tunnel in which the maximum tensile stress develops at its springline occurs when it is constructed at shallow depths in the QS layer. The results of the parametric study were used to suggest recommendations for the construction of tunnels in QS employing micro-tunneling.

关键词： Numerical model Micro-tunneling Queenston shale(QS) Lubricant fluids(LFs)

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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

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Wetting effects and strength degradation of swelling shale evaluated from multistage triaxial test

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Underground Space 2019年第2期4卷 79-97页

作者： Hayder Mohammed Salim Al-Maamori M.hesham el Naggar Silvana Micic Civil and Environmental Engineering Department The University of Western Ontario1151 Richmond St.LondonOntario N6A 5B9Canada Geotechnical research Centre Civil and Environmental Engineering DepartmentThe University of Western Ontario1151 Richmond St.LondonOntario N6A 5B9Canada

The multistage triaxial compression test was mainly utilized in this research to investigate the degradation in the strength of swelling shale under different wetting *** samples were tested in four different conditions:(1)under their natural moisture content denoted as intact,and after soaking in,(2)water,(3)polymer solution,and(4)bentonite solution,*** experimental results showed that a considerable decrease in the shale’s strength was noted after soaking in water and the lubricant fluids(LFs).The polymer solution caused the least decrease in the strength compared to other *** envelopes of the tested shale were constructed for intact and soaked *** envelopes showed fair agreement between the single stage and the multistage triaxial compression test results,indicating suitability of the multistage triaxial compression test for the tested swelling shale.

关键词： Multistage Triaxial compression Swelling shale Strength degradation Strength envelopes

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