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      • SCIESCOPUSKCI등재

        Effects of Resveratrol and Essential Oils on Growth Performance, Immunity, Digestibility and Fecal Microbial Shedding in Challenged Piglets

        Ahmed, S.T.,Hossain, M.E.,Kim, G.M.,Hwang, J.A.,Ji, H.,Yang, C.J. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.5

        A study was conducted to evaluate the effects of resveratrol and essential oils from medicinal plants on the growth performance, immunity, digestibility, and fecal microbial shedding of weaned piglets. A total of 48 weaned piglets (8 kg initial weight, 28-d-old) were randomly allotted to four dietary treatments with 3 replications of 4 piglets each. The dietary treatments were NC (negative control; basal diet), PC (positive control; basal diet+0.002% apramycin), T1 (basal diet+0.2% resveratrol), and T2 (basal diet+0.0125% essential oil blend). All piglets were orally challenged with 5 ml culture fluid containing $2.3{\times}10^8$ cfu/ml of Escherichia coli KCTC 2571 and $5.9{\times}10^8$ cfu/ml Salmonella enterica serover Typhimurium. The PC group (p<0.05) showed the highest average daily gain (ADG) and average daily feed intake (ADFI) throughout the experimental period, although feed conversion ratio (FCR) was improved in the T1 group (p>0.05). Serum IgG level was increased in the T1 group, whereas TNF-${\alpha}$ levels was reduced in the supplemented groups compared to control (p<0.05). The PC diet improved the dry matter (DM) digestibility, whereas PC and T2 diets improved nitrogen (N) digestibility compared to NC and T1 diets (p<0.05). Fecal Salmonella and E. coli counts were reduced in all treatment groups compared to control (p<0.05). Fecal Lactobacillus spp. count was increased in the T2 group compared to others (p<0.05). Dietary treatments had no significant effect on fecal Bacillus spp. count throughout the entire experimental period. Based on these results, resveratrol showed strong potential as antibiotic alternatives for reversing the adverse effects of weaning stress on growth performance, immunity and microbial environment in E. coli and Salmonella-challenged piglets.

      • SCIESCOPUSKCI등재

        Secreted Phosphoprotein 1 Promoter Genetic Variants Are Associated with the Response to Pegylated Interferon α Plus Ribavirin Combination Therapy in Egyptian Patients with Chronic Hepatitis C Virus Infection

        ( Fahmy T Ali ),( Mohamed A M Ali ),( Mayada M A Elgizawy ),( Ahmed M Elsawy ) 대한소화기학회 2015 Gut and Liver Vol.9 No.4

        Background/Aims: The T-helper 1 (TH1) immune reaction is essential for the eradication of hepatitis C virus (HCV) during pegylated interferon α (PEG-IFN-α)- and ribavirin (RBV)-based therapy in chronic HCV patients. Secreted phosphoprotein 1 (SPP1) was shown to be a crucial cytokine for the initiation of a TH1 immune response. We aimed to investigate whether SPP1 single nucleotide polymorphisms (SNPs) may influence sustained virological response (SVR) rates. Methods: Two SNPs in the promoter region of SPP1 at the .443 C>T and .1748 G>A loci were genotyped in 100 patients with chronic HCV genotype 4 infection using a TaqMan SNP genotyping assay. Results: Sixty-seven patients achieved a SVR, and 33 patients showed no SVR. Patients carrying the T/T genotype at the .443 locus showed a significantly higher SVR rate than those carrying the C/T or C/C genotype (83.67% vs 50.98%, p<0.001). At the .1748 locus, the SVR rate was significantly higher in patients with the G/G genotype than in those with the A/A genotype (88.89% vs 52.63%, p=0.028) and in patients with the G/A genotype than in those with the A/A genotype (85.29% vs 52.63%, p=0.001). Conclusions: SPP1 SNPs at .443 C>T and .1748 G>A loci may be useful markers for predicting the response to PEG-IFN-α-2b plus RBV therapy in Egyptian patients with chronic HCV genotype 4 infection. (Gut Liver 2015;9:516-524)

      • Enhanced electromechanical properties of (1-x)BiFeO<sub>3</sub>-BaTiO<sub>3</sub>-xLiNbO<sub>3</sub> ceramics by quenching process

        Ahmed Malik, R.,Hussain, A.,Kwon Song, T.,Kim, W.J.,Ahmed, R.,Soo Sung, Y.,Kim, M.H. Elsevier 2017 CERAMICS INTERNATIONAL Vol.43 No.suppl1

        A new lead-free piezoelectric ceramics (1-x) (0.67Bi<SUB>1.05</SUB>FeO<SUB>3</SUB> - 0.33BaTiO<SUB>3</SUB>)-x LiNbO<SUB>3</SUB>, abbreviated as BFBT-LNx (x = 0.00-0.030), were fabricated by conventional mixed oxide route following by quenching process and crystal structure and electromechanical properties were discussed. X-ray diffraction pattern showed that LiNbO<SUB>3</SUB> addition into 0.67Bi<SUB>1.05</SUB>FeO<SUB>3</SUB> - 0.33BaTiO<SUB>3</SUB> system did not caused any significant change in crystal structure. However, an obvious variation in electrical properties was observed. It is revealed from electrical properties that the modification of LiNbO<SUB>3</SUB> induces a phase transition from a ferroelectric to relaxor state in the 0.67Bi<SUB>1.05</SUB>FeO<SUB>3</SUB> - 0.33BaTiO<SUB>3</SUB> system. At optimum composition (x = 0.010), enhanced field-induced strain with large dynamic piezoelectric constant S<SUB>max</SUB>/E<SUB>max</SUB> = d<SUP>*</SUP><SUB>33</SUB> = 500pm / V at a relatively low field of 3.5kV / mm with lower hysteresis loss of 40% was recorded. For this composition, a high Curie temperature T<SUB>C</SUB> ~ 390<SUP>o</SUP>C was found. These properties suggests that the synthesized system is promising for high temperature actuator applications.

      • Theoretical rotational stiffness of the flexible base connection based on parametric study via the whale optimization algorithm

        Mahmoud T. Nawar,Ehab B. Matar,Hassan M. Maaly,Ahmed G. Alaaser,Osman Hamdy 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.88 No.1

        This paper handles the results of an extensive parametric study on the rotational stiffness of the flexible base connection using ABAQUS program. The results of the parametric study show the relation between the applied moment and the relative rotation for 96 different base connections. The configurations of the studied connections considered different numbers, diameters, and spacing of the anchor bolts along with different thicknesses of the base plate to investigate the effect of these parameters on the rotational stiffness behavior. The results of the previous parametric research used through the whale optimization algorithm (WOA) to detect different equation formulation of the moment-rotation (M-Ɵr) equation to detect optimum equation simulates the general nonlinear rotational behavior of the flexible base connection considering all variables used in the parametric study. WOA is a relatively new promising algorithm, which is used in different types of optimization problems. For more verification, the classical genetic algorithm (GA) is used to make a comparison with WOA results. The results show that WOA is capable of getting an optimum equation of the M-Ɵr relation, which can be used to simulate the actual rotational stiffness of the flexible base connections. The rotational stiffness at H/150 can be calculated using WOA (1) method and be used as a design aid for engineering design.

      • KCI등재

        THE WEIBULL MARSHALL-OLKIN LOMAX DISTRIBUTION WITH APPLICATIONS TO BLADDER AND HEAD CANCER DATA

        KUMAR, DEVENDRA,KUMAR, MANEESH,ABD EL-BAR, AHMED M.T.,LIMA, MARIA DO CARMO S. The Korean Society for Computational and Applied M 2021 Journal of applied mathematics & informatics Vol.39 No.5

        The proposal of new families has been worked out by many authors over recent years. Many ways to generate new families have been developed as the methods of addition, linear combination, composition and, one of the newer, the T-X family of distributions. Using this latter method, Korkmaz et al. (2018) proposed a new class called Weibull Marshall-Olkin-G (WMO-G) family. In the present work, we propose a new distribution, based on the WMO-G family, using the Lomax distribution as baseline, called Weibull Marshall-Olkin Lomax (WMOL) distribution. The hazard rate function of this distribution can be increasing, decreasing, bathtub-shaped, decreasing-increasing-decreasing and unimodal. Some properties of the proposed model are developed. Besides that, we consider method of maximum likelihood for estimating the unknown parameters of the WMOL distribution. We provide a simulation study in order to verify the asymptotic properties of the maximum likelihood estimates. The applicability of the new distribution to modeling real life data is proved by two real data sets.

      • Biochar, a potential hydroponic growth substrate, enhances the nutritional status and growth of leafy vegetables

        Awad, Y.M.,Lee, S.E.,Ahmed, M.B.M.,Vu, N.T.,Farooq, M.,Kim, I.S.,Kim, H.S.,Vithanage, M.,Usman, A.R.A.,Al-Wabel, M.,Meers, E.,Kwon, E.E.,Ok, Y.S. Butterworth-Heinemann, Ltd 2017 Journal of cleaner production Vol.156 No.-

        A hydroponics system developed using a nutrient film technique was used to evaluate the effectiveness of rice husk biochar (RB) alone or in combination with perlite (PL) as substrates for increasing the growth of leafy vegetables compared with that of PL. Seedlings of cabbage, dill, mallow, red lettuce, and tatsoi were grown hydroponically in PL, RB, and PL + RB (1:1 ratio of PL to RB, v/v) substrates for a 30-d under optimal environmental conditions in a greenhouse. Shoot length and fresh/dry masses of cabbage, dill, and red lettuce plants grown in RB substrate were decreased by 49% on average compared to those plants grown in PL substrate. In contrast, PL + RB substrate led to approximately 2-fold increases in shoot length, number of leaves, and fresh/dry masses of leafy vegetable plants compared with those grown in PL substrate. Foliar nutritional composition (Ca, Mg, K, Na, Mn, Fe, and Zn) and nitrogen status (SPAD index) of plants grown in PL + RB and PL substrates suggested the presence of optimal growth conditions for ensuring optimum yield with high quality. In addition, RB substrate contributed to respective increases of 1.2-3.5-fold in leaf K, Mg, Mn, and Zn contents in most vegetable plants compared with those grown in PL substrate. The RB alone or in combination with PL substrates decreased algal growth in the nutrient solutions as confirmed by scanning electron micrographs of microalgae on the RB surface. The results also indicated that use of PL + RB hydroponic substrate could be an alternative and effective technology for the better management of unwanted algal growth in nutrient solutions and high production of leafy vegetables.

      • SCISCIESCOPUS

        Ammonium phosphate as promised hydrogen storage material

        Barakat, N.A.M.,Ahmed, E.,Abdelkareem, M.A.,Farrag, T.E.,Al-Meer, S.,Al-Deyab, S.,Elsaid, K.,Nassar, M.M. Pergamon Press ; Elsevier Science Ltd 2015 International journal of hydrogen energy Vol.40 No.32

        Most of the reported hydrogen storage materials are either expensive or based on synthetically complicated compounds. Ammonium phosphates are cheap and available product; it is being used as fertilizer. These compounds could be utilized as hydrogen storage materials. Stoichiometrically, mono-, di- and tri-ammonium phosphate can lead to evolve 3.875, 7.867 and 11.903 hydrogen equivalent, respectively. Using Pt/C (20 wt %) leads to produce 17.28, 11.35 and 10.15% from the equivalent hydrogen in the mono-, di- and tri-ammonium phosphate, respectively. Analyzing the obtained gases by GC confirms evolution of pure hydrogen. Moreover, ion chromatography detects and ions in the liquid which indicates hydrolysis of the ammonium phosphate. Ni/C and Co/C NPs can be exploited as catalysts; Ni/C containing 20 wt% metal reveals comparable results to Pt/C. Overall, this study opens promising avenue to develop new catalysts to enhance the hydrolysis of ammonium phosphate to produce hydrogen. Comparing to the reported hydrogen storage materials, ammonium phosphates possess comparable hydrogen content 97.28, 118.3 and 115.72 kg/m<SUP>3</SUP> for mono-, di- and tri-ammonium phosphate, respectively which is very close to the MgH<SUB>2</SUB> (115.5 kg/m<SUP>3</SUP>) and not so far from ammonia borane (148.2 kg/m<SUP>3</SUP>). However, in contrast to these compounds, hydrogen can be released from the introduced storage materials by hydrolysis only using the proper catalyst. Furthermore, the hydrolysis process results in producing different acids; nitrous, nitric and phosphoric acid which should be considered in the reactor construction precautions.

      • Anti-proliferative Activities of Metallic Nanoparticles in an in Vitro Breast Cancer Model

        Loutfy, Samah A,Al-Ansary, Nadia A,Abdel-Ghani, Nour T,Hamed, Ahmed R,Mohamed, Mona B,Craik, James D,Eldin, Taher A. Salah,Abdellah, Ahmed M,Hussein, Yassmein,Hasanin, MTM,Elbehairi, Serag Eldin I Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.14

        Aims: To investigate effect of metallic nanoparticles, silver (AgNPs) and gold nanoparticles (AuNPs) as antitumor treatment in vitro against human breast cancer cells (MCF-7) and their associated mechanisms. This could provide new class of engineered nanoparticles with desired physicochemical properties and may present newer approaches for therapeutic modalities to breast cancer in women. Materials and Methods: A human breast cancer cell line (MCF-7) was used as a model of cells. Metallic nanoparticles were characterized using UV-visible spectra and transmission electron microscopy (TEM). Cytotoxic effects of metallic nanoparticles on MCF-7 cells were followed by colorimetric SRB cell viability assays, microscopy, and cellular uptake. Nature of cell death was further investigated by DNA analysis and flow cytometry. Results: Treatment of MCF-7 with different concentrations of 5-10nm diameter of AgNPs inhibited cell viability in a dose-dependent manner, with IC50 value of $6.28{\mu}M$, whereas treatment of MCF-7 with different concentrations of 13-15nm diameter of AuNPs inhibited cell viability in a dose-dependent manner, with IC50 value of $14.48{\mu}M$. Treatment of cells with a IC50 concentration of AgNPs generated progressive accumulation of cells in the S phase of the cell cycle and prevented entry into the M phase. The treatment of cells with IC50 concentrations of AuNPs similarly generated progressive accumulation of cells in sub-G1 and S phase, and inhibited the entrance of cells into the M phase of the cell cycle. DNA fragmentation, as demonstrated by electrophoresis, indicated induction of apoptosis. Conclusions: Our engineered silver nanoparticles effectively inhibit the proliferation of human breast carcinoma cell line MCF-7 in vitro at high concentration ($1000{\mu}M$) through apoptotic mechanisms, and may be a beneficial agent against human carcinoma but further detailed study is still needed.

      • Series Capacitor Compensated Resonant High Frequency Inverter with ZCS-Pulse Density Modulation for Induction Heating Fixing Roller in Copy Machine

        T. Ahmed,H Shirai,L. Gamage,K. Soshin,M Nakoaka 전력전자학회 2003 전력전자학술대회 논문집 Vol.2003 No.7(2)

        This paper presents the voltage source type half bridge lossless auxiliary inductor snubber assisted series capacitor compensated resonant high frequency inverter for induction heated fixing roller in copy machines This high-frequency inverter treated here can completely achieve zero current soft switching (ZCS) commutation for wide power regulation range under its constant frequency pulse density modulation (PDM) scheme Its transient and steady-state operating principle is originally presented for a constant frequency PDM control strategy under a ZCS operation commutation, together with its output effective power regulation characteristics-based on the PDM strategy The experimental operating performances of this ZCS-PDM high frequency inverter using IGBTs are illustrated as compared with computer Simulation ones Its power losses and actual efficiency are evaluated and discussed on the basis of Simulation and experimental results.<br/>

      • KCI등재

        Study of the Relaxation Phenomenon of Poly(vinyl chloride-co-vinylacetate-co-2-hydroxypropyl acrylate)/Poly(methyl methacrylate) Blends Using TSDC-TS Technique: Dipole-dipole Interaction Approach

        M. T. Ahmed,T. Fahmy 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.1

        The thermally stimulated discharge current (TSDC) technique was used to study the dipolar relaxation mechanism present in Poly(vinyl chloride-co-vinylacetate-co-2-hydroxypropyl acrylate) PVVH, Poly(methyl methacrylate) PMMA and their blends. TSDC global spectra of PVVH/PMMA polyblends exhibited two relaxation processes, indicating that the two polymers were not completely compatible with each other. Thermal sampling technique was used to investigate the breadth of the glass transition temperature covering the α-relaxation in each polymer. Each global spectrum was resolved into its elementary processes and was characterized by using a single relaxation time and an activation energy. These characteristics can be explained in terms of cooperative motions (dipole-dipole interactions) corresponding to long-range conformational changes, characteristic of α-relaxation. The TSDC theory was modified using dipole-dipole interaction effects. The α-relaxation was analyzed in terms of the Arrhenius relaxation times by using an iterative technique. Linearity was found to exist between the activation energy and the logarithm of the pre-exponential factor of the α-relaxation, confirming the validity of the compensation laws.

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