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      • KCI등재

        Inducing Potential Mutants in Bread Wheat Using Different Doses of Certain Physical and Chemical Mutagens

        Ghada M.Sh.M. Abaza,Hassan A. Awaad,Zakaria M. Attia,Khalid S. Abdel-lateif,Mohamed A. Gomaa,Safy M.Sh.M. Abaza,Elsayed Mansour 한국육종학회 2020 Plant Breeding and Biotechnology Vol.8 No.3

        Mutation is an effective strategy not only for creating novel variation into crop genome but also for direct releasing adapted and high-yielding genotypes. The current work explores inducing genetic variability in bread wheat using physical and chemical mutagens. Three wheat cultivars were treated by three mutagens; gamma irradiation (five doses; 250, 300, 350, 400 and 450 Gray); laser ray (three treatments; 1, 1.5, and 2 hour exposure) and EMS (three concentrations; 0.2, 0.3 and 0.4%). Besides, a combination of physical (laser) and chemical (EMS) mutagens using middle range of each treatment (1.5 hour laser and 0.3% EMS) was attempted to be applied. The treated seeds were sown in the first season and 4050 M1 plants were harvested. The harvested seeds were sown in the second season, and 78750 M2 plants were obtained. The selection was performed in second season (M2) based on morpho-physiological and yield traits; flag leaf area, flag leaf chlorophyll content, plant height, spike length, grain yield per plant and its components. Based on evaluated traits fourteen mutants were selected to be evaluated in the third generation (M3). The results indicated that the used mutagens had direct impact and significantly improved agronomic traits in derivative mutants compared to their parent cultivars. Moreover, the maximum increment in yield related traits were obtained by 0.4% EMS, 1 and 2 hour-laser, 350-Gy, 1.5 hour × 0.3% EMS and 250-Gy. The obtained results highlighted the importance of these doses of applied mutagens to induce useful genetic variability in bread wheat for improving grain yield and contributing traits.

      • SCOPUSKCI등재

        Synthesis of Borosilicate Zeotypes by Steam-assisted Conversion Method

        Mansour, R.,Lafjah, M.,Djafri, F.,Bengueddach, A. Korean Chemical Society 2007 대한화학회지 Vol.51 No.2

        펜타실 구조와 유사한 제올라이트형 결정성 보로실리케이드를 수증기 쪼임법으로 제조하였다. 실제 여러 종류의 서로 다른 붕소화합물 원료를 사용하여 만든 다양한 조성의 Na2O.SiO2.B2O3.TBA2O 겔을 건조시켜 얻은 무정형 분말을 수열합성 분위기에서 수증기를 쪼임으로써 펜타실 구조를 갖는 보로실리케이트 제올라이트를 합성하였다. 이때 MFI와 MEL 구조가 90:10의 비율을 혼합되어 있는 새로운 중간구조 물질이 얻어 졌다. 본 연구로부터, 젖어 있는 반응성 고체상 물질이 수증기와 높은 pH 분위기에서 결정화가 이루어짐을 확인하였다. X-선 회절법으로 분석한 결과 생성물은 우수한 결정성을 가질뿐만 아니라 독특한 촉매적 성질을 보일것으로 예상되는 구조를 갖는다. 또한 반전중심을 갖는 MFI 구조의 펜타실 층이 규칙적으로 쌓이는 모양을 보이지만 이는 MEL 구조의 거울상 층으로 이루어진 결함에 의해 방해된다. 생성물은 77 K 질소흡착법에 의하면 미세기공 부피가 0.160 cc/g 로서 순수한 MFI 구조 물질이 갖는 0.119 cc/g 보다 더 크며, 비교적 넓은 비표면적(~600 m2/g)을 보인다. 적외선 스펙트럼에서는 900.75 cm-1에서 흡수띠를 보이는데, 이는 붕소가 결정성 실리케이트의 사면체 구조내에 위치함을 뜻한다. Intermediate pentasil borosilicate zeolite-like materials have been crystallized by a novel method named steam-assisted conversion, which involves vapor-phase transport of water. Indeed, amorphous powders obtained by drying Na2O.SiO2.B2O3.TBA2O gels of various compositions using different boron sources are transformed into crystalline borosilicate zeolite belonging to pentasil family structure by contact with vapors of water under hydrothermal conditions. Using a variant of this method, a new material which has an intermediate structure of MFI/MEL in the ratio 90:10 was crystallized. The results show that steam and sufficiently high pH in the reacting hydrous solid are necessary for the crystallization to proceed. Characterization of the products shows some specific structural aspects which may have its unique catalytic properties. X-ray diffraction patterns of these microporous crystalline borosilicates are subjected to investigation, then, it is shown that the product structure has good crystallinity and is interpreted in terms of regular stacking of pentasil layers correlated by inversion centers (MFI structure) but interrupted by faults consisting of mirror-related layers (MEL structure). The products are also characterized by nitrogen adsorption at 77 K that shows higher microporous volume (0.160 cc/g) than that of pure MFI phase (0.119 cc/g). The obtained materials revealed high surface area (~600 m2/g). The infrared spectrum reveals the presence of an absorption band at 900.75 cm-1 indicating the incorporation of boron in tetrahedral sites in the silicate matrix of the crystalline phase.

      • 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

        Current Transport and Capacitance-Voltage Characteristics of n-InSb/p-GaP Prepared by Flash Evaporation and Liquid Phase Epitaxy

        A.A.M.Farag,F. S. Terra,G. M. M. Fahim,A. A. M. Mansour 대한금속·재료학회 2012 METALS AND MATERIALS International Vol.18 No.3

        In this paper, n-Type of InSb films were successfully fabricated on p-GaP monocrystalline substrates by both flash evaporation technique and liquid phase epitaxy to study some features of current transport in strained heterojunctions. The elemental composition of the prepared films was confirmed by energy disper-sive X-ray (EDX) spectroscopy. The morphology of the films was characterized by scanning electron microscopy (SEM). The electrical properties of the n-InSb/p-GaP junctions prepared by flash evaporation and liquid phase epitaxy were investigated through capacitance-voltage and current-voltage measure-ments, performed under dark condition in the temperature range 300-400 K. Due to misfit dislocations, the interface showed rectifying behavior. At low voltages, current in the forward direction was found to obey the diode equation and the conduction was controlled by a thermionic emission mechanism. For relatively higher voltages, conduction was dominated by a space-charge-limited conduction mechanism with single trap level. This is evidence of a depletion of the space charge region due to Fermi level pinning by sur-face states at the InSb/GaP interface. Junction parameters of the n-InSb/p-GaP like ideality factor and bar-rier height were obtained and variations were monitored as a function of temperatures. Also, an attempt to explore the governing current flow mechanism was made.

      • KCI등재

        Experimental Study of the Flexural Behaviour of RC Beams Made of Eco-friendly Sawdust Concrete and Strengthened by a Wooden Plate

        Ahmed M. Maglad,Walid Mansour,Sabry Fayed,Bassam A. Tayeh,Ahmed M. Yosri,M. Hamad 한국콘크리트학회 2023 International Journal of Concrete Structures and M Vol.17 No.6

        In this paper, the effectiveness of the strengthening by a wooden plate for reinforced concrete (RC) beams that incorporate waste sawdust (SD) as a partial substitute for fine aggregate (sand) has been investigated. To this end, two types of concrete mixtures were made: normal concrete (NC) and sawdust concrete (SDC), which was made by substituting 15% of the volume of sand with SD. Five RC beams (100 mm in depth, 200 mm in width, and 1500 mm in length) were experimentally tested for flexural behavior under four-point loading. Three strengthening schemes were used in this study. The first scheme used a wooden plate that was only fixed by an adhesive layer. The second and third schemes were applied by a wooden plate, which was fixed by an adhesive layer and steel angles (two and eleven angles). The findings of the study indicate that although the concrete's workability, compressive, and splitting tensile strengths were reduced with the addition of SD, the ultimate load of the beam with SD was lower than that of the control beam, with a slight variation of approximately 4%. Moreover, strengthening the RC beam with a wooden plate and two steel angles yielded the highest load capacity among all tested beams, 20% higher than the control specimen. The study's findings offered useful information for developing eco-friendly sawdust concrete beams with efficient strengthening techniques for potential future uses.

      • KCI등재

        Outcomes of side-to-end versus end-to-end colorectal anastomosis in nonemergent sigmoid and rectal cancers: a randomized controlled clinical trial

        Habeeb Tamer A.A.M.,Mohammad Hatem,Wasefy Tamer,Mansour Mohamed Ibrahim 대한대장항문학회 2023 Annals of Coloproctolgy Vol.39 No.3

        Purpose: The outcomes of open colorectal anastomosis of side-to-end versus end-to-end in nonemergent sigmoid and rectal cancer surgery in adults were compared. Methods: A randomized controlled trial on individuals with sigmoid and rectal cancers was conducted between September 2016 and September 2018. Results: The mean age was 62.58±12.3 years in the side-to-end anastomotic (SEA) group and 61.03±13.98 years in the end-to-end anastomotic (EEA) group. Except for the operative time, intraoperative data revealed no significant differences between the studied groups, and the SEA group revealed that the mean anastomotic time was significantly shorter. Perioperative blood loss, length of stay, reoperation, inpatient death, infection, and bleeding were significantly associated with leakage. There is a statistically significant change regarding the range of bowel frequency in the EEA group only (P=0.04). There is a statistically significant difference regarding incontinence for flatus in the SEA group only (P≤0.001). A statistically significant change in both groups regards incontinence for liquid stools (P≤0.001) and clustering of stools (P≤0.001 and P=0.043). The quality of life in the SEA group significantly dropped at 6 months and then returned to baseline as regards to physical well-being (PWB), functional well-being (FWB), and colorectal cancer symptoms (CCS) with no difference as regards SWB and EWB, while in the EEA group, the exact change happened only as regard PWB and FWB, but SWB and CCS percentage did not return to baseline. Conclusion: The SEA group offers a safe alternative approach to the EEA group.

      • KCI등재

        Statistical Optimization of Biosurfactant Production from Aspergillus niger SA1 Fermentation Process and Mathematical Modeling

        Al-hazmi Mansour A.,Moussa Tarek A. A.,Alhazmi Nuha M. 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.9

        In this study, we sought to investigate the production and optimization of biosurfactants by soil fungi isolated from petroleum oil-contaminated soil in Saudi Arabia. Forty-four fungal isolates were isolated from ten petroleum oil-contaminated soil samples. All isolates were identified using the internal transcribed spacer (ITS) region, and biosurfactant screening showed that thirty-nine of the isolates were positive. Aspergillus niger SA1 was the highest biosurfactant producer, demonstrating surface tension, drop collapsing, oil displacement, and an emulsification index (E24) of 35.8 mN/m, 0.55 cm, 6.7 cm, and 70%, respectively. This isolate was therefore selected for biosurfactant optimization using the Fit Group model. The biosurfactant yield was increased 1.22 times higher than in the nonoptimized medium (8.02 g/l) under conditions of pH 6, temperature 35°C, waste frying oil (5.5 g), agitation rate of 200 rpm, and an incubation period of 7 days. Model significance and fitness analysis had an RMSE score of 0.852 and a p-value of 0.0016. The biosurfactant activities were surface tension (35.8 mN/m), drop collapsing (0.7 cm), oil displacement (4.5 cm), and E24 (65.0%). The time course of biosurfactant production was a growth-associated phase. The main outputs of the mathematical model for biomass yield were Yx/s (1.18), and μmax (0.0306) for biosurfactant yield was Yp/s (1.87) and Yp/x (2.51); for waste frying oil consumption the So was 55 g/l, and Ke was 2.56. To verify the model’s accuracy, percentage errors between biomass and biosurfactant yields were determined by experimental work and calculated using model equations. The average error of biomass yield was 2.68%, and the average error percentage of biosurfactant yield was 3.39%.

      • KCI등재

        Wall to liquid mass transport and diffusion controlled corrosion in fixed bed reactors

        M.H. Abdel-Aziz,M. Bassyouni,I.A.S. Mansour,A. Nagi 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

        The diffusion controlled corrosion at the inner wall of a fixed bed reactor was studied in terms of the wall to liquid mass transfer coefficient. Variables studied are solution flow rate, physical properties, and packing size and geometry. The effect of drag reducing polymers on the rate of mass transfer and on the rate of corrosion was studied. The presence of the drag reducing polymer decreased the rate of both mass transfer and corrosion by a factor ranging from 8.92% to 39.47%. All variables were correlated by dimensionless equations. Possible applications of these data in heat transfer were highlighted. 2013 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V.

      • SCIEKCI등재

        Examination of Correlations Between Several Biochemical Components and Powdery Mildew Resistance of Flax Cultivars

        Aly, Aly A.,Mansour, Mahmoud T. M.,Mohamed, Heba I.,Abd-Elsalam, Kamel A. The Korean Society of Plant Pathology 2012 Plant Pathology Journal Vol.28 No.2

        A field trial was conducted in 2009/2010 and 2010/2011 growing seasons at Giza Agricultural Research Station to examine correlations between some biochemical componets and powdery mildews ($PM_s$) resistance in flax cultivars. Nine flax cultivars could be divided into five distinct groups, i.e., highly susceptible (Cortland and C.I. 2008), moderately susceptible (Giza 7, and Marshall), moderately resistant (Cass), resistant (Koto, Dakota and Wilden), and highly resistant (Ottowa 770B). The cultivars showed considerable variation in PM severity ranged from 8.05 on Ottowa 770B to 97.02% on Cortland. Total soluble proteins, total phenols, antioxidant enzymes (peroxidase and polyphenoloxidase), ascorbic acid, tocopherol, and malondialdehyde (MDA), were determined in uninfected leaves of the tested cultivars. Pearson's correlation coefficient was calculated to measure the degree of association between PM severity and each component. All components showed significant (P < 0.05) or highly significant (P < 0.01) negative correlation with PM severity except MDA, which showed positive correlation (P < 0.01). Linear regression analysis was used to evaluate the causal relationship between the biochemical components (independent variables) and PM severity (dependent variable). Coefficient of determination ($R^2$) values of the generated models ranged from 48.76 to 77.15%. Tocopherol, MDA, and proteins were the most important contributors to the total variation in PM severity as the $R^2$ values of their models were 71.78, 75.28, and 77.15%, respectively. The results of the present study suggest that tocopherol, MDA, and proteins in uninfected leaves can be used as biochemical markers to predict PM resistance in flax.

      • KCI등재

        Examination of Correlations Between Several Biochemical Components and Powdery Mildew Resistance of Flax Cultivars

        Aly A. Aly,Kamel A. Abd-Elsalam,Mahmoud T. M. Mansour,Heba I. Mohamed 한국식물병리학회 2012 Plant Pathology Journal Vol.28 No.2

        A field trial was conducted in 2009/2010 and 2010/2011growing seasons at Giza Agricultural Research Station to examine correlations between some biochemical componets and powdery mildews (PMs) resistance in flax cultivars. Nine flax cultivars could be divided into five distinct groups, i.e., highly susceptible (Cortland and C.I. 2008), moderately susceptible (Giza 7, and Marshall),moderately resistant (Cass), resistant (Koto, Dakota and Wilden), and highly resistant (Ottowa 770B). The cultivars showed considerable variation in PM severity ranged from 8.05 on Ottowa 770B to 97.02% on Cortland. Total soluble proteins, total phenols, antioxidant enzymes (peroxidase and polyphenoloxidase), ascorbic acid, tocopherol, and malondialdehyde (MDA), were determined in uninfected leaves of the tested cultivars. Pearson’s correlation coefficient was calculated to measure the degree of association between PM severity and each component. All components showed significant (P < 0.05) or highly significant (P < 0.01) negative correlation with PM severity except MDA, which showed positive correlation (P < 0.01). Linear regression analysis was used to evaluate the causal relationship between the biochemical components (independent variables)and PM severity (dependent variable). Coefficient of determination (R2) values of the generated models ranged from 48.76 to 77.15%. Tocopherol, MDA, and proteins were the most important contributors to the total variation in PM severity as the R2 values of their models were 71.78, 75.28, and 77.15%, respectively. The results of the present study suggest that tocopherol,MDA, and proteins in uninfected leaves can be used as biochemical markers to predict PM resistance in flax.

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