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Search Results: 1 - 10 of 11546 matches for " Mohamed Abdel-Latif Soliman "
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Intersection Curves of Implicit and Parametric Surfaces in R3  [PDF]
Mohamed Abdel-Latif Soliman, Nassar Hassan Abdel-All, Soad Ali Hassan, Sayed Abdel-Naeim Badr
Applied Mathematics (AM) , 2011, DOI: 10.4236/am.2011.28141
Abstract: We present algorithms for computing the differential geometry properties of Frenet apparatus {t,n,b,κ,τ} and higher-order derivatives of intersection curves of implicit and parametric surfaces in R3 for transversal and tangential intersection. This work is considered as a continuation to Ye and Maekawa [1]. We obtain a classification of the singularities on the intersection curve. Some examples are given and plotted.
Investigation of a Modified Cobalt-Free Alloy for Nuclear Application  [PDF]
Mamdouh Mahmoud Eissa, Maged Mahmoud Kassab, Samir Uoshaa El-Kameesy, Ahamed Abdel-Latif Mohamed
Journal of Materials Science and Chemical Engineering (MSCE) , 2015, DOI: 10.4236/msce.2015.39007
Abstract: Cobalt-free alloy of constituent’s “0.045%C-12.73%Ni-6.53%Cr-3.2%Mo-0.02%Ti-0.01%V” has been prepared by electro slag remelting technique. Mass attenuation coefficient, half value layer and effective atomic number have been determined for the prepared sample at photon energies 235 - 2700 keV. The results are compared with the corresponding theoretical calculations based on XCOM program and a fair agreement is obtained.
Identity Verification of Individuals Based on Retinal Features Using Gabor Filters and SVM  [PDF]
Mohamed A. El-Sayed, M. Hassaballah, Mohammed A. Abdel-Latif
Journal of Signal and Information Processing (JSIP) , 2016, DOI: 10.4236/jsip.2016.71007
Abstract: Authentication reliability of individuals is a demanding service and growing in many areas, not only in the military barracks or police services but also in applications of community and civilian, such as financial transactions. In this paper, we propose a human verification method depends on extraction a set of retinal features points. Each set of feature points is representing landmarks in the tree of retinal vessel. Extraction and matching of the pattern based on Gabor filters and SVM are described. The validity of the proposed method is verified with experimental results obtained on three different commonly available databases, namely STARE, DRIVE and VARIA. We note that the proposed retinal verification method gives 92.6%, 100% and 98.2% recognition rates for the previous databases, respectively. Furthermore, for the authentication task, the proposed method gives a moderate accuracy of retinal vessel images from these databases.
Biocontrol potential of salinity tolerant mutants of Trichoderma harzianum against Fusarium oxysporum
Mohamed, Hassan Abdel-Latif A.;Haggag, Wafaa Mohamed;
Brazilian Journal of Microbiology , 2006, DOI: 10.1590/S1517-83822006000200016
Abstract: exposing a wild-type culture of trichoderma harzianum to gamma irradiation induced two stable salt-tolerant mutants (th50m6 and th50m11). under saline conditions, both mutants greatly surpassed their wild type strain in growth rate, sporulation and biological proficiency against fusarium oxysporum, the causal agent of tomato wilt disease. tolerant t. harzianum mutants detained a capability to grow and convinced sporulation in growth media containing up to 69 mm nacl. in comparison with their parent strain, characterization of both mutants confirmed that they have reinforced contents of proline and hydroxyproline, relatively higher sodium content compared to potassium, calcium or magnesium contents, higher level of total phenols. electrophoretic analysis of total soluble proteins in the salt tolerance mutant th50m6 showed different bands accumulated in response to 69 mm nacl. data also showed that mutants produce certain active metabolites, such as chitinases, cellulases, b-galactosidases, as well as, some antibiotics i.e., trichodermin, gliotoxin and gliovirin. trichoderma mutants significantly reduced wilt disease incidence and improved yield and mineral contents of tomato plants under both saline and non-saline soil conditions, as well as, under infested and natural conditions. t. harzianum mutants were also more efficient in dropping the f. oxysporum growth in rhizosphere compared to the wild type strain. population density of both mutants in rhizosphere far exceeded that of t. harzianum wild type strain.
Biocontrol potential of salinity tolerant mutants of Trichoderma harzianum against Fusarium oxysporum
Mohamed Hassan Abdel-Latif A.,Haggag Wafaa Mohamed
Brazilian Journal of Microbiology , 2006,
Abstract: Exposing a wild-type culture of Trichoderma harzianum to gamma irradiation induced two stable salt-tolerant mutants (Th50M6 and Th50M11). Under saline conditions, both mutants greatly surpassed their wild type strain in growth rate, sporulation and biological proficiency against Fusarium oxysporum, the causal agent of tomato wilt disease. Tolerant T. harzianum mutants detained a capability to grow and convinced sporulation in growth media containing up to 69 mM NaCl. In comparison with their parent strain, characterization of both mutants confirmed that they have reinforced contents of proline and hydroxyproline, relatively higher sodium content compared to potassium, calcium or magnesium contents, higher level of total phenols. Electrophoretic analysis of total soluble proteins in the salt tolerance mutant Th50M6 showed different bands accumulated in response to 69 mM NaCl. Data also showed that mutants produce certain active metabolites, such as chitinases, cellulases, beta-galactosidases, as well as, some antibiotics i.e., trichodermin, gliotoxin and gliovirin. Trichoderma mutants significantly reduced wilt disease incidence and improved yield and mineral contents of tomato plants under both saline and non-saline soil conditions, as well as, under infested and natural conditions. T. harzianum mutants were also more efficient in dropping the F. oxysporum growth in rhizosphere compared to the wild type strain. Population density of both mutants in rhizosphere far exceeded that of T. harzianum wild type strain.
Plasma Concentration of Osteopontin (OPN) in Children with Systemic Lupus Erythematosus: Relationship with Disease Activity
Mohamed Farouk Afify, Gamal B. Mohamed, Mohamed Abd El-MaboudEsmat A. Abdel-Latif
The Open Autoimmunity Journal , 2009, DOI: 10.2174/1876894600901010059]
Abstract: Background: Osteopontin (OPN) is an important bone matrix mediator found to have key roles in inflammation and immunity. OPN is a cytokine which can play a number of roles in promoting activation of T lymphocyte, regulating balance between T-helper 1 and T-helper 2, participating in cell-induced immunologic response and stimulating B lymphocyte to express multi-clone antibodies. Overexpression of OPN has been associated with the development of the autoimmune/ lymphoproliferative syndrome. Objective: The aim of our present study was to analyze the possible correlation between the plasma concentration of OPN and disease activity in children with systemic lupus erythematosus (SLE). We also investigated the correlation between plasma IL-18 and OPN concentrations to further confirm the association of OPN with disease activity. Methods: We measured the plasma concentration of OPN, and the plasma proinflammatory IL-18 concentration in 40 SLE patients with or without renal disease (RSLE group and SLE group, respectively) and in 30 sex- and age-matched controls using enzyme immunoassay. Results: Plasma OPN concentrations were significantly higher in RSLE and SLE patients than in the controls (p = 0.000 and p = 0.002). Plasma OPN concentrations were significantly higher in RSLE patients than in the SLE patients (p = 0.000). Plasma OPN concentration correlated positively and significantly with SLE disease activity index in combined SLE patient groups (r = 0.34; p = 0.04). In RSLE patients, plasma OPN concentration showed a significant positive correlation with proinflammatory cytokine IL-18 concentration (r = 0.48; p = 0.004). Conclusion: The above results suggest that the production of OPN is associated with the inflammatory process and SLE development, and may serve as a potential disease marker of SLE.
Novel Antimicrobial Agents: Fluorinated 2-(3-(Benzofuran-2-yl) pyrazol-1-yl)thiazoles
Hanan A. Mohamed,Ehab Abdel-Latif,Bakr F. Abdel-Wahab,Ghada E. A. Awad
International Journal of Medicinal Chemistry , 2013, DOI: 10.1155/2013/986536
Abstract: A new series of 2-pyrazolin-1-ylthiazoles 8a–d and 13–16 was synthesized by cyclization of N-thiocarboxamide-2-pyrazoline with different haloketones and 2,3-dichloroquinoxaline. The structures of the new compounds were confirmed by elemental analyses as well as NMR, IR, and mass spectral data. The newly synthesized compounds were evaluated for their antimicrobial activities, and also their minimum inhibitory concentration (MIC) against most of test organisms was performed. Amongst the tested ones, compound 8c displayed excellent antimicrobial activity. 1. Introduction Pyrazolines are nitrogen-containing heterocyclic compounds, well known for their pronounced biological activity. These biological activities include antibacterial [1], antifungal [2], herbicidal [3], and insecticidal activities [4]. It was demonstrated that the combination of pyrazole with azole ring, linked to each by one sigma bond, led to more biologically active targets; for example, pyrazolylthiazoles showed excellent antimicrobial activities [5]. Continuing our work in this research field [6–9] and in an attempt to identify new and potent antimicrobial agents, we tried here to generate new benzofuryl 2-pyrazolin-1-ylthiazoles as antimicrobial agents using simple methods. 2. Results and Discussion 2.1. Chemistry The starting pyrazoline-1-carbothioamide 5 was prepared by treatment of 2-acetylbenzofuran 1 with equivalent of 4-flurobenzaldehyde 2 in the presence of 10% alcoholic NaOH in 90% ethanol with stirring at room temperature to give chaconne 3. Reaction of chalcone 3 with equivalent amount of thiosemicarbazide was performed in ethanol in the presence of 2.5 equivalent of sodium hydroxide to the target precursor 5. The resulting pyrazoline-1-carbothioamide 5 was cyclized to the corresponding 2-(3-(benzofuran-2-yl)-5-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl)-4-methyl-5-(p-subs.phenyldiazenyl)thiazole derivatives 8a–d by reaction with hydrazonoyl halides 6a–d in anhydrous ethanol and in the presence of an equivalent of triethylamine (Scheme 1). Scheme 1 The reaction product structures were elucidated by means of NMR, MS spectroscopy, and elemental analyses (Table 1). Table 1: Characteristic data of the synthesized compounds. For example, 1H NMR spectra of 8a–d contained two doublet-doublet and one triplet signals due to the presence of CH2 adjacent asymmetric carbon. The mass spectra of 8a–d showed the molecular ion peaks at m/z 481, 499, 515 and 561, respectively in agreement with the calculated masses. The reaction between pyrazoline-1-carbothioamide 5 and the equivalent amount
The Onset of Chaos in Pulsating Variable Stars
David G. Turner,Leonid N. Berdnikov,J. R. Percy,Mohamed Abdel-Sabour Abdel-Latif
Physics , 2011,
Abstract: Random changes in pulsation period occur in cool pulsating Mira variables, Type A, B, and C semiregular variables, RV Tauri variables, and in most classical Cepheids. The physical processes responsible for such fluctuations are uncertain, but presumably originate in temporal modifications of the envelope convection in such stars. Such fluctuations are seemingly random over a few pulsation cycles of the stars, but are dominated by the regularity of the primary pulsation over the long term. The magnitude of stochasticity in pulsating stars appears to be linked directly to their dimensions, although not in simple fashion. It is relatively larger in M supergiants, for example, than in short-period Cepheids, but is common enough that it can be detected in visual observations for many types of pulsating stars. Although chaos was discovered in such stars 80 years ago, detection of its general presence in the group has only been possible in recent studies.
Deoxycholate induces COX-2 expression via Erk1/2-, p38-MAPK and AP-1-dependent mechanisms in esophageal cancer cells
Eileen Looby, Mohamed MM Abdel-Latif, Veronica Athié-Morales, Shane Duggan, Aideen Long, Dermot Kelleher
BMC Cancer , 2009, DOI: 10.1186/1471-2407-9-190
Abstract: Following exposure of SKGT-4 cells to DCA, protein levels of COX-2, MAPK and PARP were examined by immunoblotting. AP-1 activity was assessed by mobility shift assay. DCA-induced toxicity was assessed by DNA fragmentation and MTT assay.DCA induced persistent activation of the AP-1 transcription factor with Fra-1 and JunB identified as the predominant components of the DCA-induced AP-1 complex. DCA activated Fra-1 via the Erk1/2- and p38 MAPK while Erk1/2 is upstream of JunB. Moreover, DCA stimulation mediated inhibition of proliferation with concomitant low levels of caspase-3-dependent PARP cleavage and DNA fragmentation. Induction of the anti-apoptotic protein COX-2 by DCA, via MAPK/AP-1 pathway appeared to balance the DCA mediated activation of pro-apoptotic markers such as PARP cleavage and DNA fragmentation. Both of these markers were increased upon COX-2 suppression by aspirin pretreatment prior to DCA exposure.DCA regulates both apoptosis and COX-2-regulated cell survival in esophageal cells suggesting that the balance between these two opposing signals may determine the transformation potential of DCA as a component of the refluxate.Bile acids are normal constituents of the gastro-intestinal tract where they act as trophic factors for the gut epithelium and as detergents for the absorption of cholesterol and fat-soluble vitamins [1,2]. Typical Western diets, rich in fat, are associated with increased incidence of gastro-intestinal cancer [3]. Dietary fat influences bile acid secretion as well as the composition of gut bacteria, which in turn determines the production levels of secondary bile acids [4-7].While bile acids such as DCA cannot induce tumors, they are generally believed to be tumor promoters. The exact mechanism of their tumor promoting activity is uncertain but it is thought to involve alterations in cellular signaling cascades including activation of protein kinase C and gene expression systems [8]. Bile acids are known mediators of cellular str
Drugs of Dependency: The Pregnant Woman and Her Infant
Julee Oei,Anne Bartu,Lucy Burns,Mohamed E. Abdel-Latif
International Journal of Pediatrics , 2011, DOI: 10.1155/2011/719894
Abstract:
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