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      • KCI등재

        Nematicidal Compounds from the Leaves of Schinus terebinthifolius Against Root-knot Nematode, Meloidogyne incognita Infecting Tomato

        Fatma M. Abdel Bar,Dina S. Ibrahim,Sahar R. Gedara,Mohammed S. Abdel-Raziq,Ahmed M. Zaghloul 한국생약학회 2018 Natural Product Sciences Vol.24 No.4

        The root-knot nematode, Meloidogyne incognita caused a serious damage to many plants. The phenolic components of the leaves of Schinus terebinthifolius were investigated as potential nematicidal agents for M. incognita. Nine compounds were isolated and characterized as viz., 1,2,3,4,6-pentagalloyl glucose (1), kaempferol-3-O-a-L-rhamnoside (Afzelin) (2), quercetin-3-O-a-L-rhamnoside (Quercetrin) (3), myricetin (4), myricetin-3-O-a-L-rhamnoside (Myricetrin) (5), methylgallate (6), protocatechuic acid (7), quercetin (8), and gallic acid (9) using nuclear magnetic resonance (NMR) spectroscopy. Compound 1 showed pronounced nematicidal activity compared to Oxamyl as a positive control. It showed the lowest eggs-hatchability (34%) and the highest mortality in nematode population (21% after 72 hours of treatment) at a concentration of 200 mg/mL. It exhibited the best suppressed total nematode population, root galling and number of eggmasses in infected tomato plants. The total carbohydrates and proteins were also significantly induced by 1 with reduction in total phenolics and increase in defense-related proteins. Thus, compound 1 could be a promising, more safe and effective natural nematicidal agent for the control of root-knot nematodes.

      • Highly efficient and reusable superhydrophobic/superoleophilic polystyrene@ Fe<sub>3</sub>O<sub>4</sub> nanofiber membrane for high-performance oil/water separation

        Moatmed, Sara M.,Khedr, Mohamed Hamdy,El-dek, S.I.,Kim, Hak-Yong,El-Deen, Ahmed G. Elsevier 2019 Journal of environmental chemical engineering Vol.7 No.6

        <P><B>Abstract</B></P> <P>Due to increasing of oil spills and high organic contamination of marine environment, developing of cost-effective and rapid oil/water separation technique has become inevitable. Herein, freestanding and flexible hybrid polystyrene nanofibers are introduced as highly efficient hybrid membrane for ultrafast oil/water separation without external pressure. Typically, different loading of Fe<SUB>3</SUB>O<SUB>4</SUB> nanoparticles embedded into polystyrene nanofibers using electrospinning to fabricate superhydrophobic/super-oleophilic membrane. The morphological shape, crystal structure and surface wettability behavior were elucidated by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and contact angel, respectively. The optimum loading of magnetite nanoparticles into the nanofiber membranes was investigated to achieve best separation performance. The obtained results demonstrated that the incorporation of (Fe<SUB>3</SUB>O<SUB>4</SUB>) nanoparticles into membrane has a significant impact for enhancing superhydrophobic properties and the separation efficiency against light and heavy oils. Among all formulations, the fabricated (PS@Fe<SUB>3</SUB>O<SUB>4</SUB>10 wt.%) membrane revealed ultrahigh flux (5000 L m<SUP>−2</SUP> h<SUP>−1</SUP>) with separation efficiency of 99.8 % for hexane under gravity driven process and excellent superhydrophobicity with water contact angle 162° moreover excellent reusability 98.5 % for 50 consecutive cycles. Interestingly, the proposed hybrid nanofiber membrane achieved distinct separation efficiencies 95 % and 92 % for food oils such as olive oil and sesame oil. Overall, the current study provides cost-effective and facile approach to distinctly improve the membrane performance for durable oil/water separation technique.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

      • KCI등재

        Microporous-activated carbons of type I adsorption isotherm derived from sugarcane bagasse impregnated with zinc chloride

        El Nemr Ahmed,Aboughaly Rawan M.,El Sikaily Amany,Masoud Mamdouh S.,Ramadan Mohamed S.,Ragab Safaa 한국탄소학회 2022 Carbon Letters Vol.32 No.1

        Sugarcane bagasse has been used as a substrate for the development of microporous nano-activated carbons for the treatment and elimination of dissolved materials from aquatic environment. The activated carbon was produced using chemical activation in one-step method with zinc chloride (ZnCl2) as the activating agent at a carbonization temperatures range from 500 to 900 °C. The effects of temperature and time of carbonization on the activated carbon product properties were thoroughly studied. The activated carbons that resulted were characterized using the N2 adsorption/desorption isotherms, Brunauer–Emmett–Teller method (BET), pore property analysis, micropore (MP) surface area, t-plot surface area, TGA, FTIR, SEM, TEM, and EDX analyses. The prepared activated carbon's point of zero charge, Boehm titration process, iodine removal percentage, and methylene blue number were also investigated. The prepared activated carbon's maximum surface area was achieved using a 2/1 impregnation ratio (dried sugarcane bagasse/ZnCl2) at 600 °C temperature of carbonization and 60 min residence time. 1402.2 m2/g, 0.6214 and 1.41 cm3/g, respectively, were the largest surface area, total pore volume, and micropore volume. As the activation temperature increased, the total pore volume increased and the BET study measured a pore diameter of 0.7 nm and a mean pore diameter of 1.77 nm.

      • KCI등재

        Development of an integrated approach for Algerian building seismic damage assessment

        Mehdi Boukri,Mohammed Naboussi Farsi,Ahmed Mébarki,Mohamed Belazougui 국제구조공학회 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.47 No.4

        This paper presents a framework for seismic damage evaluation for Algerian buildings adapted from HAZUS approach (Hazard-United States). Capacity and fragility curves were adapted to fit the Algerian building typologies (Reinforced Concrete structures, Confined or Non-Confined Masonry, etc). For prediction purposes, it aims to estimate the damages and potential losses that may be generated by a given earthquake in a prone area or country. Its efficiency is validated by comparing the estimated and observed damages in Boumerdès city, in the aftermath of Boumerdès earthquake (Algeria: May 21st 2003; Mw = 6.8). For this purpose, observed damages reported for almost 3,700 buildings are compared to the theoretical predictions obtained under two distinct modelling of the seismic hazard. In one hand, the site response spectrum is built according to real accelerometric records obtained during the main shock. In the other hand, the effective Algerian seismic code response spectrum (RPA 99) in use by the time of the earthquake is considered; it required the prior fitting of Boumerdès site PGA (Peak Ground Acceleration) provided by Ambraseys’ attenuation relationship.

      • KCI등재

        Optimization Driven MapReduce Framework for Indexing and Retrieval of Big Data

        ( Hemn Barzan Abdalla ),( Awder Mohammed Ahmed ),( M. A. Al Sibahee ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.5

        With the technical advances, the amount of big data is increasing day-by-day such that the traditional software tools face a burden in handling them. Additionally, the presence of the imbalance data in big data is a massive concern to the research industry. In order to assure the effective management of big data and to deal with the imbalanced data, this paper proposes a new indexing algorithm for retrieving big data in the MapReduce framework. In mappers, the data clustering is done based on the Sparse Fuzzy-c-means (Sparse FCM) algorithm. The reducer combines the clusters generated by the mapper and again performs data clustering with the Sparse FCM algorithm. The two-level query matching is performed for determining the requested data. The first level query matching is performed for determining the cluster, and the second level query matching is done for accessing the requested data. The ranking of data is performed using the proposed Monarch chaotic whale optimization algorithm (M-CWOA), which is designed by combining Monarch butterfly optimization (MBO) [22] and chaotic whale optimization algorithm (CWOA) [21]. Here, the Parametric Enabled-Similarity Measure (PESM) is adapted for matching the similarities between two datasets. The proposed M-CWOA outperformed other methods with maximal precision of 0.9237, recall of 0.9371, F1-score of 0.9223, respectively.

      • KCI등재

        Morphological study of porous aromatic schiff bases as a highly effective carbon dioxide storages

        Rehab Hammoda,Naser Shaalan,Mohammed H. Al-Mashhadani,Dina S. Ahmed,Rahimi M. Yusop,Ali H. Jawad,Emad Yousif 한국분석과학회 2023 분석과학 Vol.36 No.5

        Carbon dioxide (CO2) capture and storage is a critical issue for mitigating climate change. Porous aromatic Schiff base complexes have emerged as a promising class of materials for CO2 capture due to their high surface area, porosity, and stability. In this study, we investigate the potential of Schiff base complexes as an effective media for CO2 storage. We review the synthesis and characterization of porous aromatic Schiff bases materials complexes and examine their CO2 sorption properties. We find that Schiff base complexes exhibit high CO2 adsorption capacity and selectivity, making them a promising candidate for use in carbon capture applications. Moreover, we investigate the effect of various parameters such as temperature, and pressure on the CO2 adsorption properties of Schiff base complexes. The Schiff bases possessed tiny Brunauer-Emmett- Teller surface areas (4.7-19.4 m2/g), typical pore diameters of 12.8-29.43 nm, and pore volumes ranging from 0.02-0.073 cm3/g. Overall, our results suggest that synthesized complexes have great potential as an effective media for CO2 storage, which could significantly reduce greenhouse gas emissions and contribute to mitigating climate change. The study provides valuable insights into the design of novel materials for CO2 capture and storage, which is a critical area of research for achieving a sustainable future.

      • KCI등재

        Dental Panoramic Radiographic Indices as a Predictor of Osteoporosis in Postmenopausal Saudi Women

        Ayman Zaky Elsamanoudy,Madiha Mahmoud Gomaa,Rabab Mohammed Feteih,Najlaa Mohammed AlAmoudi,Ayman Zaky Elsamanoudy,Mohammed Ahmed Hassanien,Mohammed-Salleh M. Ardawi 대한골대사학회 2018 대한골대사학회지 Vol.25 No.3

        Background: Many oral presentations of osteoporosis-a bone metabolic disease-were recorded. Thus, we aimed to assess panoramic radiomorphometric indices with bone mineral density (BMD) values among Saudi postmenopausal women and its importance in the prediction of osteoporosis. Methods: A total of 431 Saudi women were enrolled in this study. Panoramic radiographs were obtained at the time of BMD measurement. Subjects were fatherly classified into; normal BMD, osteopenia, and osteoporosis groups. Serum follicle-stimulating hormone, luteinizing hormone (LH), estradiol (E2), 25-hydroxy-vitamin D (25[OH]D) and intact-parathyroid hormone were measured. Moreover, serum creatinine, calcium, and phosphate, together with serum osteocalcin (s-OC), procollagen type I N-terminal propeptide (s-PINP) and cross-linked C-terminal telopeptide of type 1 collagen (s-CTX) were measured. Receiver-operator curve (ROC) curve analysis for use of mandibular cortical width (MCW), panoramic mandibular index (PMI), and maxillary-mandibular ratio (M/M ratio) to differentiate women with osteoporosis or osteopenia from normal subjects was calculated. Cut off values of 4.6 at T score <-1 and 4.1 at T score ≤-2.5 were used. Results: Body mass index is significantly low in the osteoporotic group. There is no significant difference in serum levels of LH, E2, calcium, phosphate, and 25(OH)D between the studied groups. Moreover, s-OC, C-terminal propeptide of procollagen type I, s-PINP, s-CTX, and urinary-CTX are significantly higher in osteoporosis than normal and osteopenia groups. ROC curve analysis revealed that MCW and PMI showed significant data while M/M ratio is non-significant. Conclusions: It could be concluded that MCW as an important panoramic radiographic parameter can be used for prediction and diagnosis of osteoporosis in postmenopausal Saudi women with low BMD.

      • KCI등재

        Stem cell-derived exosomes for dentin-pulp complex regeneration: a mini-review

        Hammouda Dina A.,Mansour Alaa M,Saeed Mahmoud A.,Zaher Ahmed R.,Grawish Mohammed E. 대한치과보존학회 2023 Restorative Dentistry & Endodontics Vol.48 No.2

        This mini-review was conducted to present an overview of the use of exosomes in regenerating the dentin-pulp complex (DPC). The PubMed and Scopus databases were searched for relevant articles published between January 1, 2013 and January 1, 2023. The findings of basic in vitro studies indicated that exosomes enhance the proliferation and migration of mesenchymal cells, as human dental pulp stem cells, via mitogen-activated protein kinases and Wingless-Int signaling pathways. In addition, they possess proangiogenic potential and contribute to neovascularization and capillary tube formation by promoting endothelial cell proliferation and migration of human umbilical vein endothelial cells. Likewise, they regulate the migration and differentiation of Schwann cells, facilitate the conversion of M1 pro-inflammatory macrophages to M2 anti-inflammatory phenotypes, and mediate immune suppression as they promote regulatory T cell conversion. Basic in vivo studies have indicated that exosomes triggered the regeneration of dentin-pulp–like tissue, and exosomes isolated under odontogenic circumstances are particularly strong inducers of tissue regeneration and stem cell differentiation. Exosomes are a promising regenerative tool for DPC in cases of small pulp exposure or for whole-pulp tissue regeneration.

      • KCI등재

        Comparative study of mechanical behavior of low- and high-density polyethylene based on UVB sterilization for medical usage

        Mohamed A. Aboamer,Ahmed A. Aboamer,Doaa H. Elgohary,Tarek M. Alqahtani,Ahmed Abdel-Hadi,Samiya M. Al-Mutairi,Tarek M. El-Bagory,Khaled M. Alshareef,Nader A. Rahman Mohamed 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12

        The aim of this research is to investigate the sterilizing effect of UVB radiation on the degradation and oxidation of low- and high-density polyethylene specimens using ASTM 638 and 695. Polyethylene is a reliable, efficient, and low-cost biomaterial and an alternative to various bone transplants. Twenty high-density polyethylene (HDPE) specimens and twenty low-density polyethylene (LDPE) specimens were used for tensile and compression testing. The dosage of 13.5 J/cm 2 was chosen with an exposure time of 48 minutes during the sterilization process. In terms of mechanical tensile properties, LDPE has a lower effect compared with HDPE. The p-value of yield stress equals 3.008×10 -4 , the p-value of ultimate stress equals 2.5×10 -4 , and the p-value of break stress equals 0.0075.

      • 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.

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