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      • KCI등재

        Histopathological and genetic changes proved the anti‑cancer potential of free and nano‑capsulated sinapic acid

        Doaa A. Badr,Mohamed E. Amer,Wagih M. Abd‑Elhay,Mohamed S. M. Nasr,Tamer M. M. Abuamara,Harbi Ali,Aly F. Mohamed,Maha A. Youssef,Nasser S. Awwad,Yi‑Hsu Ju,Ahmed E. Fazary 한국응용생명화학회 2019 Applied Biological Chemistry (Appl Biol Chem) Vol.62 No.5

        Cancer is known to be a fierce disease that causes a large percentage of the deaths worldwide. The common cancer treatments; chemotherapy, radiotherapy and surgery are known for their severe side effects; therefore scientists are working on finding solutions to reduce these drawbacks. One of these treatment systems is the sustained released drugs formulations, these systems depend on the encapsulation of the chemotherapy within an emulsifying agent, in order to obtain a slow drug release of low doses over long time intervals. In this study, the anti-cancer effects of free and encapsulated sinapic acid was tested against lung (A549), and colon (CaCo2) cancer cell lines, along with normal fibroblast cells (HFB4) as a negative control. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was performed for IC50 evaluation, also cell cycle assay was performed to detect cell cycle arrest status and related anti-apoptotic and pro-apoptotic; Blc-2, BAX, and P53 gene profile fold changes post cellular treatment. Data recorded revealed that encapsulated SA showed a lower toxicity than the free form to both cell lines and also to the normal cells. The cell cycle analysis showed a cell cycle arrest at the G2/M phase post cell treatment with the free and encapsulated sinapic acid accompanied with up regulation of Bax and P53 and a down regulation of Blc-2 genes in both cell lines. The data suggest a promising anti-cancer and anti-proliferative potential of free and encapsulated sinapic acid. Also they show that the anti-cancer effect of free and encapsulated sinapic acid is quite close.

      • KCI등재

        Removal of deltamethrin insecticide over highly porous activated carbon prepared from pistachio nutshells

        A.F. Hassan,A.M. Youssef,P. Priecel 한국탄소학회 2013 Carbon Letters Vol.14 No.4

        Potassium hydroxide-activated carbons (CK21, CK11, and CK12) were prepared from pis-tachio nutshells. Physicochemical properties of activated carbons were characterized by TGA, pHpzc, Fourier transform infrared spectroscopy, scanning electron microscopy, and N2-adsorption at -196°C. The examinations showed that activated carbons have high sur-face area ranging between 695-1218 m2/g, total pore volume ranging between 0.527-0.772 mL/g, and a pore radius around 1.4 nm. The presence of acidic and basic surface C-O groups was confirmed.Batch adsorption experiments were carried out to study the effects of adsorbent dosage, temperature, initial concentration of adsorbate, and contact time on deltamethrin adsorption by activated carbons. The kinetic studies showed that the adsorp-tion data followed a pseudo-second order kinetic model. The Langmuir model showed a maximum adsorption capacity of 162.6 mg/g at 35°C on CK12. Thermodynamic studies indicated that adsorption was spontaneous and increased with temperature, suggesting an endothermic process.

      • KCI등재

        USGS Hazard Map Compatible Depth-Dependent Seismic Site Coefficients for the Upper Mississippi Embayment

        문성우,Youssef M. A Hashash,박두희 대한토목학회 2017 KSCE Journal of Civil Engineering Vol.21 No.1

        Integrated probabilistic seismic hazard and site response analysis procedure, denoted as 2014 PSHA-NL, are performed to derive probabilistic site coefficients of the Upper Mississippi Embayment (UME). The site coefficients are determined for upland and lowland profiles, and NEHRP site classes C, D, and E. The probabilistically derived coefficients are compatible with 2008 USGS hazard maps and account for the thickness of the embayment. Randomized soil profiles and four sets of pressure-dependent dynamic soil curves are used to account for the uncertainties in the dynamic soil properties. It is shown that NEHRP coefficients are only applicable for site class D soil columns less than 50 m in thickness. NEHRP coefficients greatly underestimate short-period site coefficient (Fa) for site class C profiles and overestimate Fa for site classes D and E exceeding 100 m in thickness. Long-period coefficient (Fv) is shown to have a higher depth-dependency compared to Fa. For site classes C and D, the calculated site coefficients are larger than NEHRP values for all soil columns exceeding 50 m. The pronounced depth-dependency and discrepancy with the NEHRP coefficients highlight the need to use UME specific site coefficients in assessing the seismic hazard in the embayment.

      • KCI등재후보

        Seismic behaviour of repaired superelastic shape memory alloy reinforced concrete beam-column joint

        Moncef Nehdi,M. Shahria Alam,Maged A. Youssef 국제구조공학회 2011 Smart Structures and Systems, An International Jou Vol.7 No.5

        Large-scale earthquakes pose serious threats to infrastructure causing substantial damage and large residual deformations. Superelastic (SE) Shape-Memory-Alloys (SMAs) are unique alloys with the ability to undergo large deformations, but can recover its original shape upon stress removal. The purpose of this research is to exploit this characteristic of SMAs such that concrete Beam-Column Joints (BCJs) reinforced with SMA bars at the plastic hinge region experience reduced residual deformation at the end of earthquakes. Another objective is to evaluate the seismic performance of SMA Reinforced Concrete BCJs repaired with flowable Structural-Repair-Concrete (SRC). A ¾-scale BCJ reinforced with SMA rebars in the plastic-hinge zone was tested under reversed cyclic loading, and subsequently repaired and retested. The joint was selected from an RC building located in the seismic region of western Canada. It was designed and detailed according to the NBCC 2005 and CSA A23.3-04 recommendations. The behaviour under reversed cyclic loading of the original and repaired joints, their load-storey drift, and energy dissipation ability were compared. The results demonstrate that SMA-RC BCJs are able to recover nearly all of their post-yield deformation, requiring a minimum amount of repair, even after a large earthquake, proving to be smart structural elements. It was also shown that the use of SRC to repair damaged BCJs can restore its full capacity.

      • SCIESCOPUS

        Seismic behaviour of repaired superelastic shape memory alloy reinforced concrete beam-column joint

        Nehdi, Moncef,Alam, M. Shahria,Youssef, Maged A. Techno-Press 2011 Smart Structures and Systems, An International Jou Vol.7 No.5

        Large-scale earthquakes pose serious threats to infrastructure causing substantial damage and large residual deformations. Superelastic (SE) Shape-Memory-Alloys (SMAs) are unique alloys with the ability to undergo large deformations, but can recover its original shape upon stress removal. The purpose of this research is to exploit this characteristic of SMAs such that concrete Beam-Column Joints (BCJs) reinforced with SMA bars at the plastic hinge region experience reduced residual deformation at the end of earthquakes. Another objective is to evaluate the seismic performance of SMA Reinforced Concrete BCJs repaired with flowable Structural-Repair-Concrete (SRC). A $\frac{3}{4}$-scale BCJ reinforced with SMA rebars in the plastic-hinge zone was tested under reversed cyclic loading, and subsequently repaired and retested. The joint was selected from an RC building located in the seismic region of western Canada. It was designed and detailed according to the NBCC 2005 and CSA A23.3-04 recommendations. The behaviour under reversed cyclic loading of the original and repaired joints, their load-storey drift, and energy dissipation ability were compared. The results demonstrate that SMA-RC BCJs are able to recover nearly all of their post-yield deformation, requiring a minimum amount of repair, even after a large earthquake, proving to be smart structural elements. It was also shown that the use of SRC to repair damaged BCJs can restore its full capacity.

      • KCI등재

        ON THE RECURSIVE SEQUENCE <수식>

        A. M. Ahmed,H. M. El-Owaidy,Alaa E. Hamza,A. M. Youssef 한국전산응용수학회 2009 Journal of applied mathematics & informatics Vol.27 No.1

        In this paper, we investigate the global behavior of the differ- ence equation <수식>, n = 0, 1, ..., where a, b,B ∈ [0,∞) and A, k ∈ (0,∞) with non-negative initial condi- tions. In this paper, we investigate the global behavior of the differ- ence equation <수식>, n = 0, 1, ..., where a, b,B ∈ [0,∞) and A, k ∈ (0,∞) with non-negative initial condi- tions.

      • SCIESCOPUS

        A Newly Designed Fixed Bed Redox Flow Battery Based on Zinc/Nickel System

        Mahmoud, Safe ELdeen M.E.,Youssef, Yehia M.,Hassan, I.,Nosier, Shaaban A. The Korean Electrochemical Society 2017 Journal of electrochemical science and technology Vol.8 No.3

        A fixed-bed zinc/nickel redox flow battery (RFB) is designed and developed. The proposed cell has been established in the form of a fixed bed RFB. The zinc electrode is immersed in an aqueous NaOH solution (anolyte solution) and the nickel electrode is immersed in the catholyte solution which is a mixture of potassium ferrocyanide, potassium ferricyanide and sodium hydroxide as the supporting electrolyte. In the present work, the electrode area has been maximized to $1500cm^2$ to enforce an increase in the energy efficiency up to 77.02% at a current density $0.06mA/cm^2$ using a flow rate $35cm^3/s$, a concentration of the anolyte solution is $1.5mol\;L^{-1}$ NaOH and the catholyte solution is $1.5mol\;L^{-1}$ NaOH as a supporting electrolyte mixed with $0.2mol\;L^{-1}$ equimolar of potassium ferrocyanide and potassium ferricyanide. The outlined results from this study are described on the basis of battery performance with respect to the current density, velocity in different electrolytes conditions, energy efficiency, voltage efficiency and power of the battery.

      • KCI등재후보

        Experimental and analytical investigation of steel beams rehabilitated using GFRP sheets

        A.A. El Damatty,M. Abushagur,M.A. Youssef 국제구조공학회 2003 Steel and Composite Structures, An International J Vol.3 No.6

        Aging and deterioration of existing steel structures necessitate the development of simple and efficient rehabilitation techniques. The current study investigates a methodology to enhance the flexural capacity of steel beams by bonding Glass Fibre Reinforced Plastic (GFRP) sheets to their flanges. A heavy duty adhesive, tested in a previous study is used to bond the steel and the GFRP sheet. In addition to its ease of application, the GFRP sheet provides a protective layer that prevents future corrosion of the steel section. The study reports the results of bending tests conducted on a W-shaped steel beam before and after rehabilitation using GFRP sheets. Enhancement in the moment capacity of the beam due to bonding GFRP sheet is determined from the test results. A closed form analytical model that can predict the yield moment as well as the stresses induced in the adhesive and the GFRP sheets of rehabilitated steel beam is developed. A detailed finite element analysis for the tested specimens is also conducted in this paper. The steel web and flanges as well as the GFRP sheets are simulated using three-dimensional brick elements. The shear and peel stiffness of the adhesive are modeled as equivalent linear spring systems. The analytical and experimental results indicate that a significant enhancement in the ultimate capacity of the steel beam is achieved using the proposed technique. The finite element analysis is employed to describe in detail the profile of stresses and strains that develop in the rehabilitated steel beam.

      • KCI등재

        Protective Effect of Portulaca oleracea Extract Against Lipopolysaccharide-Induced Neuroinflammation, Memory Decline, and Oxidative Stress in Mice: Potential Role of miR-146a and miR-let 7

        Rasha M. Hussein,Ahmed M. Youssef,Mousa K. Magharbeh,Saed M. Al-Dalaen,Nariman A. Al-Jawabri,Taymaa N. Al-Nawaiseh,Abdullah Al-Jwanieh,Fakhir S. Al-Ani 한국식품영양과학회 2022 Journal of medicinal food Vol.25 No.8

        Neuroinflammation is an adaptive immune response to the central nervous system (CNS) injury induced by infection or toxins. MicroRNAs (miRs) showed critical roles in neuroinflammation as either proinflammatory or anti-inflammatory molecules. Interestingly, Portulaca oleracea (purslane) is an edible plant capable of ameliorating several diseases, including headache, burns, and diabetes; however, its effect on the neuroinflammation-associated miRs was not previously investigated. This study aimed to investigate the effect of aqueous purslane extract on the neuroinflammation induced by lipopolysaccharide (LPS) in mice and to identify its effect on animal cognition, oxidative stress, and expressions of miR-146a and miR-let 7. Adult mice were divided into the following groups: Normal group, LPS group, and Purslane+LPS group. Novel target recognition test, brain histopathology, and measurement of oxidative stress and inflammatory markers were performed. The results showed that LPS group exhibited significant decline in the cognitive memory, brain histopathological injury and a decrease in the number of intact neurons compared to the normal group. Furthermore, the LPS group showed a significant increase in malondialdehyde concentration, whereas superoxide dismutase and catalase activities were decreased. The LPS group also showed an increase in the inflammatory markers tumor necrosis factor-α and nuclear factor kappa B and downregulation of miR-146a and miR-let 7 expressions in the brain cells compared to the normal group, P value <.05. Interestingly, all these changes were reversed by administration of the aqueous purslane extract. In conclusion, the aqueous purslane extract protected from LPS-induced neuroinflammation and memory decline in mice through antioxidant and anti-inflammatory effect where upregulation of miR-146a and miR-1et 7 expressions was involved.

      • KCI등재

        Citric Acid Effects on Brain and Liver Oxidative Stress in Lipopolysaccharide-Treated Mice

        Omar M.E. Abdel-Salam,Eman R. Youness,Nadia A. Mohammed,Safaa M. Youssef Morsy,Enayat A. Omara,Amany A. Sleem 한국식품영양과학회 2014 Journal of medicinal food Vol.17 No.5

        Citric acid is a weak organic acid found in the greatest amounts in citrus fruits. This study examined the effect of citric acid on endotoxin-induced oxidative stress of the brain and liver. Mice were challenged with a single intraperitoneal dose of lipopolysaccharide (LPS; 200 lg/kg). Citric acid was given orally at 1, 2, or 4 g/kg at time of endotoxin injection and mice were euthanized 4 h later. LPS induced oxidative stress in the brain and liver tissue, resulting in marked increase in lipid peroxidation (malondialdehyde [MDA]) and nitrite, while significantly decreasing reduced glutathione, glutathione peroxidase (GPx), and paraoxonase 1 (PON1) activity. Tumor necrosis factor-alpha (TNF-a) showed a pronounced increase in brain tissue after endotoxin injection. The administration of citric acid (1–2 g/kg) attenuated LPS-induced elevations in brain MDA, nitrite, TNF-a, GPx, and PON1 activity. In the liver, nitrite was decreased by 1 g/kg citric acid. GPx activity was increased, while PON1 activity was decreased by citric acid. The LPS-induced liver injury, DNA fragmentation, serum transaminase elevations, caspase-3, and inducible nitric oxide synthase expression were attenuated by 1–2 g/kg citric acid. DNA fragmentation, however, increased after 4 g/kg citric acid. Thus in this model of systemic inflammation, citric acid (1–2 g/kg) decreased brain lipid peroxidation and inflammation, liver damage, and DNA fragmentation.

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