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Evaluation of Antioxidants, Total Phenolics and Antimicrobial Activities of Ethyl Acetate Extracts From Fungi Grown on Rice Straw

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Journal of Renewable materials 2019年第7期7卷 667-682页

作者： Bahaa T.Shawky mohammed Nagah mosad A.Ghareeb gamal m.el-sherbiny Saad A.m.moghannem mohamed S.Abdel-Aziz microbial Chemistry Department National Research CentreDokki-12622CairoEgypt medicinal Chemistry Department Theodor Bilharz Research InstituteKornaish El-NileWarrak El-HadarImbaba(P.O.30)Giza 12411Egypt Botany and microbiology Department Faculty of ScienceAzhar UniversityNasr CityCairoEgypt

Rice straw(RS)collected from Egyptian agricultural environment(Al-masied village-Alsharqia Governorate-Egypt)was used as substrate for three fungal isolates namely:4b,1Asp,Pleurotus ostreatus NRRL 3501 and mixed culture of(4b,1Asp).Isolates number 4b and 1Asp were identified using the molecular technique(18S rRNA).Isolate 4b and 1Asp,were identified as Trichoderma saturnisporum mN1-EGY and Aspergillus niger mN2-EGY,*** saturnisporum mN1-EGY extract exhibited the highest antimicrobial activity compared to the other fungal *** phenolic,antimicrobial and antioxidant activities were also determined from the ethyl acetate extract of rice straw inoculated by these *** antioxidant scavenging concentration(SC50)values of the tested samples were 88.84,91.45,94.65 and 100.0μg/ml,respectively for Pleurotus sp.,Aspergiluus niger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.,after 15 days incubation,compared to ascorbic acid as positive control with SC50 value equal to 8.0μg/*** phenolic contents(TPCs)were maximum in Pleurotus *** and found to be the most polyphenolic enriched sample(380.64 mg GAE/g dry extract)compared to extracts of Aspergiluusniger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.(261.89,198.52,and 119.80 mg GAE/g dry extract),*** GC-mS analysis has been also performed for the promising extracts.

关键词： Rice straw fungi molecular identification antimicrobial antioxidant total phenolics

Exploitation of the antibacterial,antibiofilm and antioxidant activities of Salvadora Persica(miswak)extract

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Journal of Bioresources and Bioproducts 2023年第1期8卷 59-65页

作者： gamal m.el-sherbiny Ahmed mohamed Gazelly mohammed H.Sharaf Saad A.moghannemm Shehata m.E mahmoud K.A.Ismail Ahmad S.el-Hawary Botany and microbiology Department Faculty of Science(Boys)Al-Azhar UniversityCairo 11884Egypt

The Salvadora persica(***)*** stick,usually known as miswak,is still being em-ployed as an oral hygiene agent for plaque and gingivitis *** study aims to assess the antibacterial,antibiofilm,antioxidant,and phytochemical profile of *** *** ***-sica was purchased from a local market,grinded and extracted with petroleum *** disk dif-fusion,microdilution,and micro-plate assays were performed to evaluate the antibacterial and an-tibiofilm activities of the prepared extract at different concentrations against𝛽-lactam resistance Streptococcus *** radical scavenging 2,2-diphenyl-1-picrylhydrazyl(DPPH)and stable radical cationic chromophore,2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate)(ABTS)methods were used to determine their antioxidant *** and spectrometric analyses were performed using gas chromatography-mass(GC-mS)*** minimum inhibitory concentration(mIC)of *** extract against𝛽-lactam resistance Streptococcus species ranged from 6.25 to 12.5 mg/*** maximum suppression of biofilm formation by *** extract was observed at mIC with a percentage of 68.66%,against Streptococcus *** *** ex-tract exhibited antioxidant activity with IC 50 of 20μg/mL and 35μg/mL from DPPH and ABTS,*** phytochemical characterization showed the presence of 22 compounds with ma-jor compounds;benzyl isothiocyanate(36.21%)and n-hexadecanoic acid(27.62%).The *** extract exhibited antibacterial activity against𝛽-lactam resistant Streptococcus species,showing a promising natural alternative that could be a treatment option.

关键词： β-lactam resistance Streptococcus species S.persica extract Antibacterial Antibiofilm Antioxidant GC-mS analysis

Does salinity change determine zooplankton variability in the saline Qarun Lake(Egypt)?

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Chinese Journal of Oceanology and Limnology 2015年第6期33卷 1368-1377页

作者： gamal m.el-SHABRAWY elena V.ANUFRIIEVA mousa O.GERmOUSH mohamed E.GOHER Nickolai V.SHADRIN National Institute of Oceanography and Fisheries Fish Research Station mLR Key Laboratory of Saline Lake Resources and Environments Institute of Mineral Resources Institute of Biology of the Southern Seas Biology Department College of ScienceAl Jouf University

Zooplankton and 14 abiotic variables were studied during August 2011 at 10 stations in Lake Qarun, Egypt. Stations with the lowest salinity and highest nutrient concentrations and turbidity were close to the discharge of waters from the el-Bats and E1-Wadi drainage systems. A total of 15 holozooplankton species were identified. The salinity in Lake Qarun increased and fluctuated since 1901：12 g/L in 1901; 8.5 g/L in 1905; 12.0 g/L in 1922; 30.0 g/L in 1985; 38.7 g/L in 1994; 35.3 g/L in 2006, and 33.4 g/L in 2011. The mean concentration of nutrients （nitrate, nitrite and orthophosphate） gradually increased from 35, 0.16 and 0.38 μg/L, respectively, in 1953-1955 to 113, 16.4, and 30.26 μg/L in 2011. From 1999-2003 some decrease of species diversity occurred. Average total zooplankton density was 30 000 ind./m^3 in 1974-1977; 356 125 ind./m^3 in 1989; 534 000 ind./m^3 in 1994-1995; from 965 000 to 1 452 000 ind./m^3 in 2006, and 595 000 ind./m^3 in 2011. A range of long-term summer salinity variability during the last decades was very similar to a range of salinity spatial variability in summer 2011. There is no significant correlation between zooplankton abundance and salinity in spatial and long-term changes. We conclude that salinity fluctuations since at least 1955 did not directly drive the changes of composition and abundance of zooplankton in the lake. A marine community had formed in the lake, and it continues to change. One of the main drivers of this change is a regular introduction and a pressure of alien species on the existent community. Eutrophication also plays an important role. The introduction ofmnemiopsis leidyi, first reported in 2014, may lead to a start of a new stage of the biotic changes in Lake Qarun, when eutrophication and the population dynamics of this ctenophore will be main drivers of the ecosystem change.

关键词： saline lake Copepoda Rotifera mnemiopsis leidyi alien species

microstructure and mechanical properties of hot extruded 6016 aluminum alloy/graphite composites

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Journal of materials Science & Technology 2018年第9期34卷 1580-1591页

作者： mohamed m.el-Sayed Seleman mohamed m.Z.Ahmed Sabbah Ataya Department of metallurgical and materials Engineering Faculty of Petroleum and Mining Engineering Suez University 43518 Suez Egypt Suez and Sinai metallurgical and materials Research Center of Scientific Excellence (SSmmR-CSE) 43518 Suez Egypt The British University in Egypt Mechanical Engineering Deportment El-Sherouk City 11837 Cairo Egypt Department of mechanical Engineering College of Engineering AI Imam Mohammad Ibn Saud Islamic University Riyadh 11432 saudi Arabia

The incorporation of graphite particles into AA6016 aluminum alloy matrix to fabricate metal/ceramic composites is still a great challenge and various parameters should be considered. In this study, dense AA6016 aluminum alloy/（0-20 wt%） graphite composites have successfully been fabricated by powder metallurgy process. At first, the mixed aluminum and graphite powders were cold compacted at 200 mPa and then sintered at 500 ℃ for 1 h followed by hot extrusion at 450 ℃. The influence of ceramic phases（free graphite and in-situ formed carbides） on microstructure, physical and mechanical properties of the produced composites were finally investigated. The results show that the fabricated composites have a relative density of over 98%. SEm observations indicate that the graphite has a good dispersion in the alloy matrix even at high graphite content. Hardness of all the produced composites was higher than that of aluminum alloy matrix. No cracks were observed at strain less than 23% for all hot extruded *** strength, reduction in height, ultimate tensile stress, fracture stress, yield stress, and fracture strain of all Al/graphite composites were determined by high precision second order equations. Both compressive and ultimate tensile strengths have been correlated to microstructure constituents with focusing on the in-situ formed ceramic phases, silicon carbide（SiC） and aluminum carbide（Al4 C3）. The ductile fracture mode of the produced composites became less dominant with increasing free graphite content and in-situ formed carbides. Wear resistance of Al/graphite composites was increased with increasing graphite content. Aluminum/20 wt% graphite composite exhibited superior wear resistance over that of AA6016 aluminum alloy.

关键词： AA6016/graphite composites Hot extrusion In-situ carbides mechanical properties Wear resistance Fracture behavior

The Effect of Atrial Septal Defect Closure on Cardiac Volumetric Changes in Adults, Transcatheter Versus Surgical Closure, a Pilot Cardiac magnetic Resonance Study

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Congenital Heart Disease 2023年第6期18卷 679-691页

作者： Amr mansour Noha m.gamal Alaa m.Nady Amr Ibraheem Dalia m.Salah Khaled m.el-maghraby Cardiology Department Congenital and Structural Heart Disease UnitAin Shams University HospitalsFaculty of MedicineAin Shams UniversityCairoEgypt Cardiology Department Faculty of MedicineAssuit UniversityAssuitEgypt Cardiothoracic Surgery Department Faculty of MedicineAssuit UniversityAssuitEgypt Anesthesia Department Faculty of MedicineAssuit UniversityAssuitEgypt

Background:Closure of an atrial septal defect(ASD)reduces right-side heart volumes by abolishing shunting with simultaneous improvement of the left ventricle(LV)ﬁlling and functions due to ventricular interdependence,thereby improving ***,studies conducted on atrial volume changes after ASD closure are *** magnetic resonance(CmR)is considered as the gold standard method for measuring cardiac volume and ***:We aimed to study the effect of transcatheter and surgical closure of secundum ASD on cardiac volumes and systolic functions as well as the fate of tricuspid regurgitation(TR),using CmR ***:We prospectively enrolled 30 adult patients with isolated secundum ASD who were referred to ASD *** evaluation of cardiac chambers indexed volumes,systolic function,myocardial mass index,and tricuspid regurgitant fraction were done at before and 6 months after ***:RV volumes decreased in both groups when compared to baseline(p-value 0.001),the device group had more reduction in volumes and more improvement in RV function after closure(p-value 0.001)when compared to the surgical *** changes in the RV mass index were insigniﬁcant between both groups(p-value 0.31).Functional TR improved to the same extent in both *** ventricular end diastolic volume index(LVEDVI)and LV mass index increased sig-niﬁcantly in both groups when compared to baseline in both groups but with no difference between groups p-value 0.01),left ventricular end systolic volume index(LVESVI)changes were insigniﬁ*** systolic function improved in patients who underwent device closure only(63.53±3.85 vs.67.13±4.34,p-value 0.01).There was a signiﬁcant reduction in right atrial(RA)volumes and an insigniﬁcant decrease in left atrial(LA)volumes,with no difference between ***:Transcatheter and surgical secundum ASD closure resulted in volumetric changes in some cardiac chambers with better improvement in bi-ventricular

关键词： Atrial septal defect closure cardiac volumetric changes functional tricuspid regurgitation cardiac CmR

Effect of Conductive Fillers on the Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

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Chinese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： m.H.Abd-el Salam S.el-gamal m.mohsen D.m.Abd el-maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDmS） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALS）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （ΔHm） were estimated by differential scanning calorimetry （DSC）. Tm and the degree of crystallinity （χc） of PDmS composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDmS loaded with different contents of filler has been studied. mullins ratio （Rm） was found to be dependent on the filler type and content. It was found that, Rm increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALS. moreover, the hysteresis in PDmS-CB composites was more pronounced than in PDmS-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDmS composites containing different fillers. A negative correlation was observed between Vf and Rm.

关键词： Positron annihilation Positronium Free volume Si-rubber Composite Cyclic mechanical properties.

A computer-based image analysis for tear ferning featuring

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Journal of Innovative Optical Health Sciences 2015年第5期8卷 40-49页

作者： Ali S.Saad gamal A.el-Hiti Ali m.masmali Department of Biomedical Technology College of Applied medical Sciences King Saud University P.O.Box 10219 Riyadh 11433Saudi Arabia Cornea Research Chair(CRC) Department of Optometry College of Applied Medical SciencesKing Saud University Riyadh 11433Saudi Arabia

The present work focuses on the development of a novel computer-based approach for tear ferning(TF)*** original TF images of the recently developedfive-point grading scale have been used to assign a grade for any TF image automatically.A vector characteristic(VC)representing each grade was built using the reference images.A weighted combination between features selected from textures analysis using gray level co-occurrence matrix(GLCm),power spectrum(PS)analysis and linear specificity of the image were used to build the VC of each grade.A total of 14 features from texture analysis were *** at di®erent frequency points and number of line segments in each image were also *** features from GLCm have shown significant di®erences between the recently developed grading scale images which are:angular second moment at 0and 45,contrast,and correlation at 0and 45;thesefive features were all included in the characteristic *** specific power frequencies were used in the VC because of the discrimination *** of line segments was also chosen because of dissimilarities between images.A VC for each grade of TF reference images was constructed and was found to be significantly different from each other'*** is a basic and fundamental step toward an automatic grading for computer-based diagnosis for dry eye.

关键词： Objective grading tear ferning new grading scale texture analysis image processing PS

Tailored pancreatic reconstruction after pancreaticoduodenectomy: a single-center experience of 892 cases

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Hepatobiliary & Pancreatic Diseases International 2017年第5期16卷 528-536页

作者： Ayman el Nakeeb Ahmad m Sultan Ehab Atef Ali Salem mostaffa Abu Zeid Ahmed Abu el Eneen gamal el Ebidy mohamed Abdel Wahab Gastroenterology Surgical Center Mansoura UniversityMansoura 35516 Egypt

BACKGROUND: Pancreatic reconstruction following pancreaticoduodenectomy(PD) is still debatable even for pancreatic surgeons. Ideally, pancreatic reconstruction after PD should reduce the risk of postoperative pancreatic fistula(POPF) and its severity if developed with preservation of both exocrine and endocrine pancreatic functions. It must be tailored to control the morbidity linked to the type of *** study was to show the best type of pancreatic reconstruction according to the characters of pancreatic stump. mETHODS: We studied all patients who underwent PD in our center from January 1993 to December 2015. Patients were categorized into three groups depending on the presence of risk factors of postoperative complications: low-risk group(absent risk factor), moderate-risk group(presence of one risk factor) and high-risk group(presence of two or more risk factors). RESULTS: A total of 892 patients underwent PD for resection of periampullary tumor. BmI >25 kg/m~2, cirrhotic liver, soft pancreas, pancreatic duct diameter mm, and pancreatic duct location from posterior edge mm are risk variables for development of postoperative complications. POPF developed in 128(14.3%) patients. Delayed gastric emptying occurred in 164(18.4%) patients, biliary leakage developed in 65(7.3%) and pancreatitis presented in 20(2.2%). POPF in low-, moderate-and high-risk groups were 26(8.3%), 65(15.7%) and 37(22.7%) patients, respectively. Postoperative morbidity and mortality were significantly lower with pancreaticogastrostomy(PG) in high-risk group, while pancreaticojejunostomy(PJ) decreases incidence of postoperative steatorrhea in all groups. CONCLUSIONS: Selection of proper pancreatic reconstruction according to the risk factors of patients may reduce POPF and postoperative complications and mortality. PG is superior to PJ as regards short-term outcomes in high-risk group but PJ provides better pancreatic function in all groups and therefore, PJ is superior in l

关键词： periampullary tumor pancreaticogastrostomy pancreaticojejunostomy pancreaticoduodenectomy postoperative pancreatic fistula

Jellyfish-inspired alginate composite hydrogel filter prepared by macro-micro double bionic strategy for efficient water purification

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 141-157页

作者： Huiting Peng Yan Chen Jiaopan Lin Chelsea Benally mohamed gamal el-Din Junkai Gao School of Naval Architecture and marinetime Zhejiang Ocean UniversityZhoushan 316022China Department of Civil and Environmental Engineering University of AlbertaEdmontonAB T6G 1H9Canada

Recently,research on hydrogel materials with a porous structure and superior water absorption capabilities significantly ***,the hydrogel under gravity-driven separation conditions often exhibit an unstable pore structure,poor mechanical properties,and limited *** this end,this work presents a novel approach that combines a macro-micro double bionic strategy with a triple crosslinking method to develop a multifunctional alginate composite hydrogel filter(2%-SA-κCG-PVA-Ca^(2+),2%-SKP-Ca^(2+)for short)with a stable pore structure and superior mechanical properties,which possessed an umbrella-shaped structure resembling that of *** 2%-SKPCa^(2+)filter was synthesized using polyvinyl alcohol(PVA)as a stable structure-directing agent,and sodium alginate(SA)andκ-carrageenan(κ-CG)as polymer *** distinctive umbrellashaped hydrogel of 2%-SKP-Ca^(2+)filter,formed through the triple crosslinking method,overcomes the limitations of unstable pore structure and poor durability seen in hydrogels prepared by traditional crosslinking ***,the utilization of the 2%-SKP-Ca^(2+)filter in water treatment demonstrates its good selective permeability,excellent resistance to fouling,and extended longevity,which enables it to simultaneously achieve the multifunctional water purification and the coating of multi-substrate anti-fouling ***,not only does this research provide an efficient,multifunctional,highly pollution-resistant preparation method for designing a new filter,but it also confirms the application prospect of the macro-micro dual bionic strategy developed in this study in complex water treatment.

关键词： Triple crosslinking method Alginate Umbrella-shaped Jellyfish Water purification