Kafr ash Shaykh, Egypt
Kafr ash Shaykh, Egypt

Kafrelsheikh University is an Egyptian university established in 2006, located at Kafr Elsheikh, in the middle of the Nile Delta.The University has a number of faculties such as: Engineering, medicine, physiotherapy and nursing, pharmacy, veterinary medicine, science, education, agriculture, arts, specific education, commerce, physical education. Wikipedia.

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Ramadan A.E.-M.M.,Kafr El Sheikh University
Journal of Molecular Structure | Year: 2012

A new series of nickel(II) complexes with the tetraaza macrocyclic ligand have been synthesized as possible functional models for nickel-superoxide dismutase enzyme. The reaction of 5-amino-3-methyl-1-phenylpyrazole-4- carbaldehyde (AMPC) with itself in the presence of nickel(II) ion yields, the new macrocyclic cationic complex, [NiL(NO 3) 2], containing a ligand composed of the self-condensed AMPC (4 mol) bound to a single nickel(II) ion. A series of metathetical reactions have led to the isolation of a number of newly complexes of the types [NiL]X 2; X = ClO 4 and BF 4, [NiLX 2], X = Cl and Br (Scheme 1). Structures and characterizations of these complexes were achieved by several physicochemical methods namely, elemental analysis, magnetic moment, conductivity, and spectral (IR and UV-Vis) measurements. The electrochemical properties and thermal behaviors of these chelates were investigated by using cyclic voltammetry and thermogravimetric analysis (TGA and DTG) techniques. A distorted octahedral stereochemistry has been proposed for the six-coordinate nitrato, and halogeno complexes. For the four-coordinate, perchlorate and fluoroborate, complex species a square-planar geometry is proposed. The measured superoxide dismutase mimetic activities of the complexes indicated that they are potent NiSOD mimics and their activities are compared with those obtained previously for nickel(II) complexes. The probable mechanistic implications of the catalytic dismutation of O2- by the synthesized nickel(II) complexes are discussed. The DNA-binding properties of representative complexes [NiLCl 2] and [NiL](PF 4) 2 have been investigated by the electronic absorption and fluorescence measurements. The results obtained suggest that these complexes bind to DNA via an intercalation binding mode and the binding affinity for DNA follows the order: [NiLCl 2] □ [NiL](PF 4) 2. © 2012 Elsevier B.V. All rights reserved.

The adsorption mechanism and inhibition performance of some Azo-azomethine derivatives [2-hydroxyphenylazo-2′,4′-dihydroxy-3′- formylbenzene(Azo-1), 2-carboxyphenylazo-2′,4′-dihydroxy-3′- formylbenzene (Azo-II), 2-hydroxyphenylazo-2′,4′-dihydroxy-3′- {2-hydroxyphenylazomethine}(Azo-I-azomethine I) and 2-carboxyphenylazo-2′, 4′-dihydroxy-3′-{2-hydroxyazo methane} (Azo-II-azomethine II) on mild steel at temperatures ranging from 298 K to 333 K have been studied using molecular dynamics (MD) simulation and quantum chemical computational methods. The results obtained revealed that these molecules could effectively adsorb on Fe (0 0 1) surface and the active adsorption sites of these molecules are the nitrogen, oxygen atoms and special negatively charged carbon atoms. All the inhibitors studied had unique corrosion inhibition performance with Azo-II-azomethine II showing the highest inhibition performance at lower temperature ranges from 298 K to 313 K and Azo-II displaying the highest inhibition performance at higher temperature ranges of 323 K and 333 K. Some quantum chemical parameters and the Mulliken charge densities on the optimized structure of inhibitors were calculated using the 6-31â-G basis set method to provide further insight into the mechanism of the corrosion inhibition process. The local reactivity was analyzed through the Fukui function and condensed softness indices in order to know the possible sites of nucleophillic and electrophillic attacks. © 2013 Elsevier B.V. All rights reserved.

Khalafalla R.E.,Kafr El Sheikh University
PLoS ONE | Year: 2011

A survey study on gastrointestinal parasites in 113 faecal samples from stray cats collected randomly from Kafrelsheikh province, northern region of Nile delta of Egypt; was conducted in the period between January and May 2010. The overall prevalence was 91%. The results of this study reported seven helminth species: Toxocara cati (9%), Ancylostoma tubaeforme (4%), Toxascaris leonina (5%), Dipylidium caninum (5%), Capillaria spp. (3%), Taenia taeniformis (22%) and Heterophyes heterophyes (3%), four protozoal species: Toxoplasma gondii (9%), Sarcocyst spp. (1%), Isospora spp. (2%) and Giardia spp. (2%) and two arthropod species; Linguatula serrata (2%) and mites eggs (13%). The overall prevalence of intestinal parasites may continue to rise due to lack of functional veterinary clinics for cat care in Egypt. Therefore, there is a need to plan adequate control programs to diagnose, treat and control gastrointestinal parasites of companion as well as stray cats in the region. © 2011 Reda E. Khalafalla.

In the present study, the free vibration, mechanical buckling and thermal buckling analyses of multi-layered graphene sheets (MLGSs) are investigated. Eringen's nonlocal elasticity equations are incorporated in new two-variable plate theories accounting for small-scale effects. The MLGSs are taken to be perfectly bonded to the surrounding medium. The governing differential equations of this model are solved analytically under various boundary conditions and taking into account the effect of van der Waals forces between adjacent layers. New functions for the displacements are proposed here to satisfy the different boundary conditions. Comparison of the results with those being in the open literature is made. This comparison illustrates that the present scheme yields very accurate results. Furthermore, the influences of nonlocal coefficient, moduli of the surrounding elastic medium and aspect ratio on the frequencies and buckling of the embedded MLGSs are examined. © 2014 Springer-Verlag Wien.

This paper deals with the vibration and buckling behavior of exponentially graded material (EGM) sandwich plate resting on elastic foundations under various boundary conditions. New functions for midplane displacements are suggested to satisfy the different boundary conditions. The elastic foundation is modeled as Pasternak's type which can be either isotropic or orthotropic and as a special case it converges to Winkler's foundation if the shear layer is neglected. The present EGM sandwich plate is assumed to be made of a fully ceramic core layer sandwiched by metal/ceramic EGM coat. The governing equations of the dynamic response of non-homogeneous composite plates are deduced by using various shear deformation plate theories. Numerical results for the natural frequencies and critical buckling loads of several types of symmetric EGM sandwich plates are presented. The validity of the present solution is demonstrated by comparison with solutions available in the literature. The influences of the inhomogeneity parameter, aspect ratio, thickness ratio and the foundation parameters on the natural frequencies and critical buckling loads are investigated. © 2012 Elsevier Ltd.

Nenaah G.,Kafr El Sheikh University
World Journal of Microbiology and Biotechnology | Year: 2013

Antimicrobial activity of solvent extracts and flavonoids of Calotropis procera growing wild in Saudi Arabia was evaluated using the agar well-diffusion method. A bioassay-guided fractionation of the crude flavonoid fraction (Cf3) of MeOH extract which showed the highest antimicrobial activity led to the isolation of four flavonoid glycosides as the bioactive constituents. Structure of compounds have been elucidated using physical and spectroscopic methods including (UV, IR, 1H, 13C-NMR, DEPT, 2D 1H-1H COSY, HSQC, HMBC and NOESY). Compounds were found to be the 3-O-rutinosides of quercetin, kaempferol and isorhamnetin, besides the flavonoid 5-hydroxy-3,7-dimethoxyflavone-4′-O-β-glucopyranoside. Most of the isolated extracts showed antimicrobial activity against the test microorganisms, where the crude flavonoid fraction was the most active, diameter of inhibition zones ranged between 15.5 and 28.5 mm against the tested bacterial strains, while reached 30 mm against the fungal Candida albicans. The minimal inhibitory concentrations varied from 0.04 to 0.32 mg/ml against all of the tested microorganisms in case of the crude flavonoid fraction. Quercetin-3-O-rutinoside showed superior activity over the remainder flavonoids. The Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) were more susceptible than the Gram-negative (Pseudomonas aeruginosa and Salmonella enteritidis) and the yeast species were more susceptible than the filamentous fungi. The study recommend the use of such natural products as antimicrobial biorationals. © 2013 Springer Science+Business Media Dordrecht.

Ghali M.,Kafr El Sheikh University
Journal of Luminescence | Year: 2010

The author reports on a strong fluorescence quenching of a model transport protein, bovine serum albumin BSA, when bioconjugated with CdS quantum dots QDs. The 4.4 nm size CdS QDs were synthesized using wet chemistry method and were characterized using UV-vis spectroscopy, scanning electron microscopy SEM and X-ray diffraction XRD techniques. It was found that the BSA fluorescence quenching increases linearly with increasing the CdS QDs concentrations in the range of 3×10-7-2.0×10-6 mol L-1. This quenching is explained in terms of Stern-Volmer equation and is ascribed to static quenching with quenching constant 1.321×104 L mol-1 at 300 K. © 2010 Elsevier B.V. All rights reserved.

Sobhy M.,Kafr El Sheikh University
Physica E: Low-Dimensional Systems and Nanostructures | Year: 2014

In the present paper, the sinusoidal shear deformation plate theory (SDPT) is reformulated using the nonlocal differential constitutive relations of Eringen to analyze the bending and vibration of the nanoplates, such as single-layered graphene sheets, resting on two-parameter elastic foundations. The present SDPT is compared with other plate theories. The nanoplates are assumed to be subjected to mechanical and thermal loads. The equations of motion of the nonlocal model are derived including the plate foundation interaction and thermal effects. The governing equations are solved analytically for various boundary conditions. Nonlocal theory is employed to bring out the effect of the nonlocal parameter on the bending and natural frequencies of the nanoplates. The influences of nonlocal parameter, side-to-thickness ratio and elastic foundation moduli on the displacements and vibration frequencies are investigated. © 2013 Elsevier B.V.

Essential oils of Achillea biebersteinii, A. santolina and A. mellifolium were obtained by hydrodistillation, then analyzed using gas chromatography (GC) and GC/mass spectrometry (MS). The obtained oils showed considerable toxic and growth inhibitory activities against the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). The time of exposure, the technique used and the stage treated, all were activity-determinant factors, where A. biebersteinii oil showed the strongest insecticidal activity and the adult stage was more susceptible than larvae. Using topical application, LC50 values of A. biebersteinii, A. santolina and A. mellifolium oils after 96h of exposure of larvae were 30.3, 47.8 and 62.3μg/mg insect, respectively. In this case, LC50s against adults were ranged between 21.8 and 50.7μg/mg insects. Using treated filter papers, the LC50 values after 96h of exposure against larvae were ranged between 124.9 and 212.0μL/cm2, while against adults were ranged between 113.0 and 196.8μL/cm2. In the fumigant bioassay, LC50s after 96h of exposure against larvae were between 41.7 and 93.2μL/L air, while against adults were between 36.1 and 80.6μL/L air. When prepared as nano-emulsions and tested as fumigants, toxicity of oils was increased dramatically, where LC50 values after 96h of exposure against larvae and adults were ranged between 11.0 and 27.5μL/L air and 8.8 and 21.3μL/L air, respectively. When exposed as 2nd instar larvae to sub-lethal doses-treated grains, the developmental course, life span and F1 progeny of T. castaneum were significantly affected, where the oil of A. santolina showed the strongest activity. All of these developmental disruptions led to a great reduction in the number of adults that undergo successful emergence. © 2013 Elsevier B.V.

Essential oils of Achillea biebersteinii, Achillea santolina and Achillea mellifolium were obtained by hydrodistillation and analyzed using gas chromatography/mass spectrometry. The plant oils were tested for their toxic and repellent activities against the Khapra beetle, Trogoderma granarium (Everts) (Coleoptera: Dermestidae). T. granarium was sensitive to the oils via topical application, contact and fumigation bioassays, where A. biebersteinii oil was the most toxic regardless of the technique used. Using topical application, a dosage of 15 μg/mg insect of A. biebersteinii oil was sufficient to kill 100 and 83.2.0 % after 7 days exposure of adults and 2nd instar larvae, respectively. Meanwhile, twice this concentration of A. santolina and A. mellifolium oils caused 90.4 (72.5 %) and 73.8 (60.1 %) adult and larval mortality after 7 days, respectively. Using fumigation and 7 days exposure, a concentration of 50.0 μl/l air of A. biebersteinii oil displayed the strongest activity (percentage adult and larval mortalities of 100.0 and 88.0 %), respectively, while A. santolina and A. mellifolium oils at the same concentration caused 92.5 (76.8 %) and 76.1 (61.3 %) adult and larval mortality, respectively. The three oils were strongly repellent to the larvae and adults of T. granarium. The repellent activity was time and concentration-dependent, where A. biebersteinii oil was the most effective, even though at low concentrations (percentage repellency of 100 and 81.0 % were recorded against adults and larvae after 6 h exposure to a concentration of 0.22 μl/cm2, respectively). Results suggested the potential use of Achillea oils as natural grain protectants against T. granarium. © 2013 Springer-Verlag Berlin Heidelberg.

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