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      • KCI등재

        Heat transfer characteristics and entropy generation for wing-shaped-tubes with longitudinal external fins in cross-flow

        Sayed Ahmed E. Sayed Ahmed,Osama M. Mesalhy,Mohamed A. Abdelatief 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.6

        A numerical study is conducted to clarify heat transfer characteristics, effectiveness and entropy generation for a bundle of wingshaped-tubes attached to Longitudinal fins (LF) at downstream side. The air-side Re a ranged from 1.8 x 10 3 to 9.7 x 10 3 . The fin height (h f ) and fin thickness (δ) have been changed as: (2 mm ≤ h f ≤ 12 mm) and (1.5 mm ≤ δ ≤ 3.5 mm). The analysis of entropy generation is based on the principle of minimizing the rate of total entropy generation that includes the generation of entropy due to heat transfer and friction losses. The temperature field around the wing-shaped-tubes with (LF) is predicted using commercial CFD FLUENT 6.3.26 software package. Correlations of Nu a , St a , and Bejan number (Be), as well as the irreversibility distribution ratio (Φ) in terms of Re a and design parameters for the studied bundle are presented. Results indicated that, installing fins with heights from 2 to 12 mm results in an increase in Nu a from 11 to 36% comparing with that of wing-shaped tubes without fins (NOF). The highest and lowest values of effectiveness (ε) at every value of the considered Re a range are occurred at h f = 6 mm and (NOF), respectively. The wing-shaped-tubes heat exchanger with h f = 6 mm has the highest values of (ε), efficiency index (η) and area goodness factor (G a ) and also the lowest values of Φ and hence the best performance comparing with other arrangements. The minimum values of Φ are occurred at h f = 6 mm. (Be) decreases with increasing Re a for all studied h f . The heat transfer irreversibility predominates for (1800 ≤ Re a ≤ 4200) while the opposite is true for (6950 < Re a ≤ 9700). δ has negligible effect on Nu a and heat transfer irreversibility. Comparisons between the experimental and numerical results of the present study and those, previously, obtained for similar available studies showed good agreements.

      • 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.

      • 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

        Apocynin abrogates methotrexate-induced nephrotoxicity: role of TLR4/NF-κB-p65/p38-MAPK, IL-6/STAT-3, PPAR-γ, and SIRT1/FOXO3 signaling pathways

        Emad H. M. Hassanein,Ahmed M. Sayed,Omnia A. M. Abd El-Ghafar,Zainab M. M. Omar,Eman K. Rashwan,Zuhair M. Mohammedsaleh,So Young Kyung,Jae Hyeon Park,Hyung Sik Kim,Fares E. M. Ali 대한약학회 2023 Archives of Pharmacal Research Vol.46 No.4

        The present study was designed to evaluate the potential renoprotective impacts of apocynin (APC) against nephrotoxicity induced by methotrexate (MTX) administration. To fulfill this aim, rats were allocated into four groups: control; APC (100 mg/kg/day; orally); MTX (20 mg/kg; single intraperitoneal dose at the end of the 5th day of the experiment); and APC +MTX (APC was given orally for 5 days before and 5 days after induction of renal toxicity by MTX). On the 11th day, samples were collected to estimate kidney function biomarkers, oxidative stress, pro-inflammatory cytokines, and other molecular targets. Compared to the MTX control group, treatment with APC significantly decreased urea, creatinine, and KIM-1 levels and improved kidney histological alterations. Furthermore, APC restored oxidant/antioxidant balance, as evidenced by a remarkable alleviation of MDA, GSH, SOD, and MPO levels. Additionally, the iNOS, NO, p-NF-κB-p65, Ace-NF-κB-p65, TLR4, p-p38-MAPK, p-JAK1, and p-STAT-3 expressions were reduced, while the IκBα, PPAR-γ, SIRT1, and FOXO3 expressions were significantly increased. In NRK-52E cells, MTX-induced cytotoxicity was protected by APC in a concentration-dependent manner. In addition, increased expression of p-STAT-3 and p-JAK1/2 levels were reduced in MTX-treated NRK-52E cells by APC. The in vitro experiments revealed that APC-protected MTX-mediated renal tubular epithelial cells were damaged by inhibiting the JAK/STAT3 pathway. Besides, our in vivo and in vitro results were confirmed by predicting computational pharmacology results using molecular docking and network pharmacology analysis. In conclusion, our findings proved that APC could be a good candidate for MTX-induced renal damage due to its strong antioxidative and anti-inflammatory bioactivities.

      • SCOPUSKCI등재

        Cardenolides and β-Sitosterol Glucoside from Pergularia tomentosa L.

        Ahmed A. Gohar,M. M. El Olemy,Essam Abdel Sattar,M. El Said,M. Niwa 한국생약학회 2000 Natural Product Sciences Vol.6 No.3

        The aerial parts of Pergularia tomentosa L. afforded three cardenolides, desglucouzarin, coroglaucigenin and uzarigenin, in addition to β-sitosterol glucoside. The isolated compounds were identified by physical and spectral means, including IR, UV, [α]_D 1D-, 2D-NMR and FAB-MS experiments. The cardenolides, ghalakinoside, calactin and pergularoside previously reported from roots, were also identified in the aerial parts.

      • KCI등재

        The effect of microfinance on women’s empowerment : Evidence from Malaysia

        Sayed Samer Ali AL-SHAMI,Muhammad M. RAZALI,Izaidin MAJID,Ahmed ROZELAN,Nurulizwa RASHID 이화여자대학교 아시아여성학센터 2016 Asian Journal of Women's Studies(AJWS) Vol.22 No.3

        Microfinance is widely known as a financial development tool for those deprived of access to financial services, especially women. However, the literature provides conflicting evidence and shows that women’s empowerment may not, or may only be partially achieved through microcredit, especially in Muslim societies. This study seeks to scrutinize the effect of Amanah Ikhtiar Malaysia (AIM), a microcredit institution, on Malay Muslim women in an urban area. A quasi-experimental method was used to conduct a cross sectional survey of 500 old and new clients. Informal semi-structured interviews were conducted with 20 current clients who had received microcredit two years earlier. The findings show that AIM microcredit empowered the women and enhanced gender equality. It enabled women to access financial capital, form their micro- and smallbusinesses and obtain an income which helped them to contribute to household expenditure. Even though the effect of microcredit was partial, it provided them bargaining power for decision-making and controlling of resources and enhanced their self-esteem in their households and communities. Pembiayaan mikro secara meluasnya dikenali sebagai kaedah membangunkan mereka yang tidak diberi peluang akses perkhidmatan kewangan lain, khasnya di kalangan golongan wanita. Walau bagaimanapun, literatur kajian lampau telah mengemukakan bukti yang bercanggah di mana pembiayaan mikro kepada golongan wanita terutamanya mereka dalam masyarakat Islam mungkin tidak langsung atau mungkin sebahagiannya sahaja memberi kesan terhadap kejayaan mereka. Kajian ini bertujuan untuk meneliti kesan Amanah Ikhtiar Malaysia (AIM) iaitu sebuah institusi pembiayaan mikro, di kalangan wanita Melayu Islam di kawasan bandar. Satu kaedah kuasieksperimen telah digunakan untuk menjalankan kajian terhadap 500 pelanggan lama dan baru pembiayaan mikro. Temubual informal separa berstruktur telah dijalankan bersama 20 pelanggan yang sedang menerima pembiayaan mikro dalam tempoh dua tahun sebelumnya. Hasil kajian menunjukkan bahawa pembiayaan mikro AIM menjadikan wanita bertambah berjaya dan dapat menyumbang terhadap kesamarataan antara gender. Ia membolehkan mereka memperolehi modal, membentuk perniagaan mikro atau kecil dan seterusnya memperolehi pendapatan yang dapat membantu mereka untuk menyumbang kepada perbelanjaan isi rumah. Walaupun kesan pembiayaan mikro ini menyumbang kepada sebahagian sahaja peningkatan ini, namun ia dapat menyediakan mereka kuasa tawar-menawar untuk membuat keputusan, kawalan ke atas sumber dan meningkatkan keyakinan diri golongan ini.

      • SCIESCOPUSKCI등재

        Synthesis and Pharmacological Screening for Muscle Relaxant, Anticonvulsant, and Sedative Activities of Certain Organic Compounds Produced by Michael Addition

        Said , Makarem M.,Ahmed, Amany A. E.,El-Alfy, Abir T. The Pharmaceutical Society of Korea 2004 Archives of Pharmacal Research Vol.27 No.12

        Michael addition of certain nucleophiles on ${\alpha}$ , ${\beta}$-unsaturated ketones 1 led to the formation of adducts 2-7 as well as the reaction of arylidene derivatives with secondary amines afforded the amino compounds 9 and 11. Also, dialkylmalonates were treated with ${\alpha}$-cyano cinnamide to afford 13. On the other hand, double Michael cycloaddition of ethylcyanoacetate or tetrachlorophthalic anhydride to the suitable divinylketone were synthesized to produce 15-17. Selected compounds (13 and 6) were screened for muscle relaxant, anticonvulsant, and sedative activities using established pharmacological models. Their activities were compared with that of phenobarbital sodium taken as standard. Compound 6 was the most potent muscle relaxant while compounds 13a and 13c offered the highest anticonvulsant activity. Meanwhile compound 13c showed the highest potentiation of phenobarbital induced sleep in mice.

      • KCI등재

        CONTINUATION THEOREM OF FRACTIONAL ORDER EVOLUTIONARY INTEGRAL EQUATIONS

        Ahmed M. A. El-Sayed,Mohamed A. E. Aly 한국전산응용수학회 2002 Journal of applied mathematics & informatics Vol.9 No.2

        The fractional order evolutionary integral equations have been considered by the first author in \cite{AMA.4}, the existence, uniqueness and some other properties of the solution have been proved. Here we study the continuation of the solution and its fractional order derivative. Also we study the generality of this problem and prove that the fractional order diffusion problem, the fractional order wave problem and the initial value problem of the equation of evolution are special cases of it. The abstract diffusion-wave problem will be given also as an application. The fractional order evolutionary integral equations have been considered by the first author in \cite{AMA.4}, the existence, uniqueness and some other properties of the solution have been proved. Here we study the continuation of the solution and its fractional order derivative. Also we study the generality of this problem and prove that the fractional order diffusion problem, the fractional order wave problem and the initial value problem of the equation of evolution are special cases of it. The abstract diffusion-wave problem will be given also as an application.

      • KCI등재

        Life Span Extension of Caenorhabditis elegans by Novel Pyridoperimidine Derivative

        Ahmed A. R. Sayed,Kamal M. El-Shaieb,Aboul-Fetouh E. Mourad 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.1

        Zwitterions formed from the addition of triphenylphosphine to dialky acetylene-dicarboxylates attack the nucleus of both 1H-perimidine (1) and 1H-benzo[d]imidazole (9) to form novel pyrido[1,2,3-cd]perimidine and imidazo[4,5,1-ij]quinoline derivatives in moderate yields (64-72%). The biological activity of the products has been studied. Compound 3a was found to extend life span of wild type Caenorhabditis elegans under standard laboratory conditions. Both heat stress and induced chemical stress resistance of wild type C. elegans were improved in a reverse dose-dependent manner due to 3a treatment. In addition, treatment of worms with compound 3a significantly attenuated the formation of advanced glycation end products in a reverse dose-dependent manner.

      • Shear behaviour of thin-walled composite cold-formed steel/PE-ECC beams

        Ahmed M. Sheta,Xing Ma,Yan Zhuge,Mohamed A. ElGawady,Julie E. Mills,El-Sayed Abd-Elaal 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.46 No.1

        The novel composite cold-formed steel (CFS)/engineered cementitious composites (ECC) beams have been recently presented. The new composite section exhibited superior structural performance as a flexural member, benefiting from the lightweight thin-walled CFS sections with improved buckling and torsional properties due to the restraints provided by thinlayered ECC. This paper investigated the shear performance of the new composite CFS/ECC section. Twenty-eight simply supported beams, with a shear span-to-depth ratio of 1.0, were assembled back-to-back and tested under a 3-point loading scheme. Bare CFS, composite CFS/ECC utilising ECC with Polyethylene fibres (PE-ECC), composite CFS/MOR, and CFS/HSC utilising high-strength mortar (MOR) and high-strength concrete (HSC) as replacements for PE-ECC were compared. Different failure modes were observed in tests: shear buckling modes in bare CFS sections, contact shear buckling modes in composite CFS/MOR and CFS/HSC sections, and shear yielding or block shear rupture in composite CFS/ECC sections. As a result, composite CFS/ECC sections showed up to 96.0% improvement in shear capacities over bare CFS, 28.0% improvement over composite CFS/MOR and 13.0% over composite CFS/HSC sections, although MOR and HSC were with higher compressive strength than PE-ECC. Finally, shear strength prediction formulae are proposed for the new composite sections after considering the contributions from the CFS and ECC components.

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