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      • KCI등재

        Nanostructured BaTi1-xSnxO3 ferroelectric materials for electrocaloric applications and energy performance

        Benyoussef M.,Mura T.,Saitzek S.,Azrour F.,Blach J.-F.,Lahmar A.,Gagou Y.,El Marssi M.,Sayede A.,Jouiad M. 한국물리학회 2022 Current Applied Physics Vol.38 No.-

        Nanostructured BaTi1-xSnxO3 (x = 0, 0.05 & 0.075) were successfully synthesized using the modified Pechini processing method. The phase purity and symmetry were examined by X-ray diffraction and Raman spectroscopy. Tetragonal symmetry was obtained for BaTiO3 (BT) while orthorhombic symmetry for Sn doped BT. BT exhibits an up-shift of the Curie temperature towards high temperatures (TC = 139 ◦C). In contrast, a down-shift was recorded for Sn doped BT. Then, indirect electrocaloric (EC) adiabatic temperature change ΔT and the energy storage performances were determined based on ferroelectric hysteresis loops. Interestingly, large EC responsivity of ΔT/ΔE = 0.81 × 10-6 K m/V was obtained for the BT accompanied with a moderate stored energy of 23 mJ/cm3 but with a high energy efficiency of 67%. The incorporation of Sn in BT was found to broaden the EC responsivity and to improve the energy efficiency up to 90%, recorded for the 5% Sn doped BT.

      • KCI등재

        Purification and Characterization of Anabaena flos-aquae Phenylalanine Ammonia-Lyase as a Novel Approach for Myristicin Biotransformation

        Asmaa M. Arafa,Afaf E. Abdel-Ghany,Samih I. El-Dahmy,Sahar Abdelaziz,Yassin El-Ayouty,Ashraf S. A. El-Sayed 한국미생물·생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.4

        Phenylalanine ammonia-lyase (PAL) catalyzes the reversible deamination of phenylalanine to cinnamic acid and ammonia. Algae have been considered as biofactories for PAL production, however, biochemical characterization of PAL and its potency for myristicin biotransformation into MMDA (3-methoxy-4, 5-methylenedioxyamphetamine) has not been studied yet. Thus, PAL from Anabaena flos-aquae and Spirulina platensis has been purified, comparatively characterized and its affinity to transform myristicin was assessed. The specific activity of purified PAL from S. platensis (73.9 μmol/mg/min) and A. flos-aquae (30.5 μmol/mg/min) was increased by about 2.9 and 2.4 folds by gel-filtration comparing to their corresponding crude enzymes. Under denaturing-PAGE, a single proteineous band with a molecular mass of 64 kDa appeared for A. flos-aquae and S. platensis PAL. The biochemical properties of the purified PAL from both algal isolates were determined comparatively. The optimum temperature of S. platensis and A. flos-aquae PAL for forward or reverse activity was reported at 30oC, while the optimum pH for PAL enzyme isolated from A. flos-aquae was 8.9 for forward and reverse activities, and S. platensis PAL had maximum activities at pH 8.9 and 8 for forward and reverse reactions, respectively. Luckily, the purified PALs have the affinity to hydroaminate the myristicin to MMDA successfully in one step. Furthermore, a successful method for synthesis of MMDA from myristicin in two steps was also established. Gas chromatography-mass spectrometry (GC-MS) analysis was conducted to track the product formation.

      • SCIESCOPUSKCI등재

        Cultivation of a New Microalga, Micractinium reisseri, in Municipal Wastewater for Nutrient Removal, Biomass, Lipid, and Fatty Acid Production

        Abou-Shanab, Reda A.I.,El-Dalatony, Marwa M.,EL-Sheekh, Mostafa M.,Ji, Min-Kyu,Salama, El-Sayed,Kabra, Akhil N.,Jeon, Byong-Hun 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.3

        Coupling of advanced wastewater treatment with microalgae cultivation for low-cost lipid production was demonstrated in this study. The microalgal species Micractinium reisseri and Scenedesmus obliquus were isolated from municipal wastewater mixed with agricultural drainage. M. reisseri was selected based on the growth rate and cultivated in municipal wastewater (influent, secondary and tertiary effluents) which varied in nutrient concentration. M. reisseri showed an optimal specific growth rate (${\mu}_opt$) of 1.15, 1.04, and 1.01 1/day for the influent and the secondary and tertiary effluents, respectively. Secondary effluent supported the highest phosphorus removal (94%) and saturated fatty acid content (40%). The highest lipid content (40%), unsaturated fatty acid content, including monounsaturated and polyunsaturated fatty acids (66%), and nitrogen removal (80%) were observed for tertiary effluent. Fatty acids accumulating in the microalgal biomass (M. reisseri) were mainly composed of palmitic acid, oleic acid, linoleic acid, and ${\alpha}$-linolenic acid. Cultivation of M. reisseri using municipal wastewater served a dual function of nutrient removal and biofuel feedstock generation.

      • KCI등재

        Technical and Economic Investigation of Solar Photovoltaic (SPV) Refrigeration System in Eastern Province of Saudi Arabia

        M. A. I. EL-SHAARAWI,A. AL-QUTUB,S. A. M. SAID,A. ADEBIYI 대한설비공학회 2013 International Journal Of Air-Conditioning and Refr Vol.21 No.3

        The paper presents the performance and economic analysis of a simple photovoltaic powered vapor compression refrigeration system carried out on winter days in the eastern province of the Kingdom of Saudi Arabia. The system has a 66W DC refrigerator, 100W PV mono-crystalline module and a 100 Ah battery bank. The thermal loads were distributed in the refrigerator cabin using ice trays of 300mL each for a total mass of 2.1 kg. The system performed continuously without any interruption or fault for the entire time of the experiment. The minimum time taking for complete formation of ice in the trays was 6 h and 40 min. A larger area to volume ratio, which enhances the heat transfer is created due to this load distribution pattern. A refrigeration e±-ciency of 60% was calculated after ice formation has been completed. At the maximum solar radiation level, the best PV e±ciency and solar panel orientation e±ciencies were 15.5% and 98%,respectively. It was however observed from the cost analysis that the system would not be economical without government subsidy on the system components or alleviating the current subsidy on the electricity cost in Saudi Arabia.

      • KCI등재

        Immune Defense of Rats Immunized with Fennel Honey, Propolis, and Bee Venom Against Induced Staphylococcal Infection

        Sayed, S.M.,El-Ella, Ghada A. Abou,Wahba, Nahed M.,Nisr, Neveen A. El,Raddad, Khaled,Rahman, M.F. Abd El,Hafeez, M.M. Abd El,Aamer, Ahmed Abd El Fattah The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.3

        The objective of this work was to evaluate the potency of bee product-immunized rats to overcome an induced Staphylococcus aureus infection. Forty rats were divided to eight groups: T1, T3, and T5 received, respectively, fennel honey, ethanol, and aqueous propolis extracts orally, and T2, T4, and T6 were administered the respective materials intraperitoneally; T7 received bee venom by the bee sting technique; and T8 was the control group. All groups were challenged by a bovine clinical mastitis isolate of S. aureus. Each rat received 2mL of broth inoculated with $1{\times}10^5$ colony-forming units/mL intraperitoneally. Two weeks post-induced infection all rats were sacrificed and eviscerated for postmortem inspection and histopathological study. Three rats from T8 and one rat from T7 died before sacrifice. Another two rats, one each in T4 and T5, had morbidity manifestations. The remaining experimental animals showed apparently healthy conditions until time of sacrifice. Postmortem inspection revealed that all T8 rats showed different degrees of skeletal muscle and internal organ paleness with scattered focal pus nodules mainly on lungs and livers. All rats of the treated groups showed normal postmortem features except three rats. A dead rat in group T7 showed focal pus nodules on the lung surface only, whereas the affected two rats in groups T4 and T5 appeared normal except with some pus nodules, but much smaller than in the control, scattered on the hepatic surface and mesentery. Histopathological studies revealed that T8 rats had typical suppurative bronchopneumonia and or severe degenerative and necrobiotic changes in hepatic tissues. Three affected rats of the treated groups showed slight bronchopneumonia or degenerative hepatic changes only. The other animals of the treated groups showed completely normal parenchymatous organs with stimulated lymphatic tissues. It was concluded that all tested previously bee product-immunized rats could significantly challenge the induced S. aureus infection (P < .01). The effects were more pronounced in rats that had received fennel honey solution.

      • SCIESCOPUSKCI등재

        Nutrient Digestibility, Ruminal Fermentation Activities, Serum Parameters and Milk Production and Composition of Lactating Goats Fed Diets Containing Rice Straw Treated with Pleurotus ostreatus

        Kholif, A.E.,Khattab, H.M.,El-Shewy, A.A.,Salem, A.Z.M.,Kholif, A.M.,El-Sayed, M.M.,Gado, H.M.,Mariezcurrena, M.D. Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.3

        The study evaluated replacement of Egyptian berseem clover (BC, Trifolium alexandrinum) with spent rice straw (SRS) of Pleurotus ostreatus basidiomycete in diets of lactating Baladi goats. Nine lactating homo-parity Baladi goats (average BW $23.8{\pm}0.4$ kg) at 7 d postpartum were used in a triplicate $3{\times}3$ Latin square design with 30 d experimental periods. Goats were fed a basal diet containing 0 (Control), 0.25 (SRS25) and 0.45 (SRS45) (w/w, DM basis) of SRS. The Control diet was berseem clover and concentrate mixture (1:1 DM basis). The SRS45 had lowered total feed intake and forages intake compared to Control. The SRS25 and SRS45 rations had the highest digestibilities of DM (p = 0.0241) and hemicellulose (p = 0.0021) compared to Control which had higher (p<0.01) digestibilities of OM (p = 0.0002) and CP (p = 0.0005) than SRS25 and SRS45. Ruminal pH and microbial protein synthesis were higher (p<0.0001) for SRS25 and SRS45 than Control, which also had the highest (p<0.0001) concentration of TVFA, total proteins, non-protein N, and ammonia-N. All values of serum constituents were within normal ranges. The Control ration had higher serum globulin (p = 0.0148), creatinine (p = 0.0150), glucose (p = 0.0002) and cholesterol (p = 0.0016). Both Control and SRS25 groups had the highest (p<0.05) milk (p = 0.0330) and energy corrected milk (p = 0.0290) yields. Fat content was higher (p = 0.0373) with SRS45 and SRS25 groups compared with Control. Replacement of BC with SRS in goat rations increased milk levels of conjugated linoleic acid and unsaturated fatty acids compared with Control. It was concluded that replacing 50% of Egyptian berseem clover with SRS in goat rations improved their productive performance without marked effects on metabolic indicators health.

      • KCI등재

        Obesity may be erythropoietin dose-saving in hemodialysis patients

        ( Ghada M. El-kannishy ),( Abir F. Megahed ),( Mona M. Tawfik ),( Ghada El-said ),( Rabab T. Zakaria ),( Nahed A. Mohamed ),( Eman M. Taha ),( Alzhraa A. Ammar ),( Abeer M. Abd Eltawab ),( Nagy A. Say 대한신장학회 2018 Kidney Research and Clinical Practice Vol.37 No.2

        Background: In dialysis patients, the obesity-survival paradox still requires an explanation. Anemia and high doses of erythropoiesis-stimulating agents (ESAs) are associated with worse outcomes in the hemodialysis (HD) population. In the present study, we explored the relation between obesity and anemia control in a sample of maintenance HD patients in Egypt. Methods: This multicenter observational study included 733 patients on maintenance HD from 9 hemodialysis centers in Egypt. Clinical and laboratory data as well as average doses of ESAs and parenteral iron were recorded. The erythropoietin resistance index (ERI) was calculated. Results: Obesity, defined as a body mass index (BMI) ≥ 30 kg/m<sup>2</sup>, was present in 22.6% of the studied population. The target hemoglobin level (10.0-11.5 g/dL) was achieved in 27.3% of non-obese and 25.3% of obese patients, with no significant difference. The median serum ferritin and the values of transferrin saturation index did not differ significantly between these two groups. The weekly ESA dose was significantly lower in obese than in non-obese patients (P = 0.0001). A trend toward higher ESA doses and ERI values was observed in patients with lower BMIs (P < 0.0001). Multiple linear regression revealed that the BMI and urea reduction ratio were the strongest predictors of the ERI. Conclusion: Our study adds more evidence to obesity-associated advantages in HD patients. BMI may determine ESA response, with better responses observed in patients with higher BMIs.

      • KCI등재

        Immune Defense of Rats Immunized with Fennel Honey, Propolis, and Bee Venom Against Induced Staphylococcal Infection

        S.M. Sayed,Ghada A. Abou El-Ella,Nahed M. Wahba,Neveen A. El Nisr,Khaled Raddad,M.F. Abd El Rahman,M.M. Abd El Hafeez,Ahmed Abd El Fattah Aamer 한국식품영양과학회 2009 Journal of medicinal food Vol.12 No.3

        The objective of this work was to evaluate the potency of bee product-immunized rats to overcome an induced Staphylococcus aureus infection. Forty rats were divided to eight groups: T1, T3, and T5 received, respectively, fennel honey, ethanol, and aqueous propolis extracts orally, and T2, T4, and T6 were administered the respective materials intraperitoneally; T7 received bee venom by the bee sting technique; and T8 was the control group. All groups were challenged by a bovine clinical mastitis isolate of S. aureus. Each rat received 2mL of broth inoculated with 1×105 colony-forming units/mL intraperitoneally. Two weeks post-induced infection all rats were sacrificed and eviscerated for postmortem inspection and histopathological study. Three rats from T8 and one rat from T7 died before sacrifice. Another two rats, one each in T4 and T5, had morbidity manifestations. The remaining experimental animals showed apparently healthy conditions until time of sacrifice. Postmortem inspection revealed that all T8 rats showed different degrees of skeletal muscle and internal organ paleness with scattered focal pus nodules mainly on lungs and livers. All rats of the treated groups showed normal postmortem features except three rats. A dead rat in group T7 showed focal pus nodules on the lung surface only, whereas the affected two rats in groups T4 and T5 appeared normal except with some pus nodules, but much smaller than in the control, scattered on the hepatic surface and mesentery. Histopathological studies revealed that T8 rats had typical suppurative bronchopneumonia and or severe degenerative and necrobiotic changes in hepatic tissues. Three affected rats of the treated groups showed slight bronchopneumonia or degenerative hepatic changes only. The other animals of the treated groups showed completely normal parenchymatous organs with stimulated lymphatic tissues. It was concluded that all tested previously bee product-immunized rats could significantly challenge the induced S. aureus infection (P<.01). The effects were more pronounced in rats that had received fennel honey solution.

      • KCI등재

        Antimicrobial Activity of New 4,6-Disubstituted Pyrimidine, Pyrazoline, and Pyran Derivatives

        Mahmoud M. M. Ramiz,Wael A. El-Sayed,Asmaa I. El-Tantawy,Adel A. H. Abdel-Rahman 대한약학회 2010 Archives of Pharmacal Research Vol.33 No.5

        A number of new 2,6-didisubstituted pyrimidine, pyrazoline, and pyran derivatives were synthesized starting from their chalcone derivative. The synthesized compounds displayed different degrees of antimicrobial activity against Bscillus subtilis (Gram-positive), Pseudomonas aeruginosa (Gram-negative), and Streptomyces species (Actinomycetes).

      • SCIESCOPUSKCI등재

        Molluscicidal Activity and Clinico-pathological Effect of Agave lophantha

        El-Sayed, M.M.,Abdel-Hadi, M.,El-Nahas, H.A. The Pharmaceutical Society of Korea 1991 Archives of Pharmacal Research Vol.14 No.1

        Dry powder and different extracts of Agave lophantha were tested against Biomphalaria alexandrina. The results showed that the butanol extract has high molluscicidal activity. The activity of the dry powder has been found to be stable under the effect of some simulated field conditions. Also the toxicological effect of the plant on mice was tested through determination of certain parameters such as total protein, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and acid phosphatase enzymes as well as histopathological study on liver and kidney.

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