Showing papers by "Cairo University published in 1989"
TL;DR: The data show that Gram-positive bacteria were more sensitive to the antimicrobial compounds in spices than Gram-negative bacteria, and Thyme and cumin oils possessed very strong antimicrobial activity compared with the other essential oils.
577 citations
TL;DR: In this paper, gas-liquid chromatography was used to determine the essential oil compositions of thyme, cumin, clove, caraway, rosemary, and sage, and the antifungal potential of the oils against Aspergillus parasiticus was investigated.
Abstract: Gas-liquid chromatography was used to determine the essential oil compositions of thyme, cumin, clove, caraway, rosemary, and sage. The basic components of these oils were thymol, cumin aldehyde, eugenol, carvonc, borneol and thujonc, respectively. The antifungal potential of the oils against Aspergillus parasiticus were investigated. The essential oils caused complete inhibition of both mycelial growth and aflatoxin production. The effectiveness followed the sequence: thyme > cumin > clove > caraway > rosemary > sage. The major components of the essential oils produced an inhibitory effect at minimum inhibitory concentrations equal to those obtained with the oils.
298 citations
TL;DR: Some spice essential oils (caraway, clove, cumin, rosemary, sage and thyme) and their major constituents were added to emulsified linoleic acid in aqueous media to examine their antioxidant activity as mentioned in this paper.
Abstract: Some spice essential oils (caraway, clove, cumin, rosemary, sage and thyme) and their major constituents were added to emulsified linoleic acid in aqueous media to examine their antioxidant activity. The methods used for measuring linoleic acid oxidation were coupled oxidation ofβ-carotene, conjugated diene formation and thiobarbituric acid test. The essential oils under study possess an antioxidant effect and this phenomenon was increased by increasing their concentration. Generally, the effectiveness of the various essential oils on linoleic acid oxidation was in the following descending order: caraway >sage>cumin>rosemary>thyme>clove. It appears that there was a relationship between the antioxidant effect and the chemical composition of the oils.
289 citations
TL;DR: In this article, simple model systems composed of refined cottonseed oil and thyme oil or clove oil, without additives, were designed to approximate conditions in natural oils in order to study their oxidation behavior.
Abstract: Simple model systems composed of refined cottonseed oil and thyme oil or clove oil, without additives, were designed to approximate conditions in natural oils in order to study their oxidation behavior. Three methods were used to follow cottonseed oil oxidation, i.e., coupled oxidation withβ-carotene, the TBA test and hydroperoxide number. The results illustrate that clove and thyme oils at various concentrations exhibit antioxidant activity and this phenomenon for clove oil is superior to that of thyme oil. Sensory evaluation tests indicate that the addition of thyme oil or clove oil to cottonseed oil at concentrations ranging from 50 to 1200 ppm do not affect the odor note of cottonseed oil. Therefore, thyme and clove essential oils are recommended for use as natural antioxidants to suppress lipid oxidation.
133 citations
TL;DR: The hepatic sonographic patterns from 50 patients undergoing operations for bleeding esophageal varices were compared with the interpretation of the histological findings in a hepatic wedge biopsy obtained during surgery to believe that sonography gave a more accurate diagnosis of schistosomiasis.
Abstract: The hepatic sonographic patterns from 50 patients undergoing operations for bleeding esophageal varices were compared with the interpretation of the histological findings in a hepatic wedge biopsy obtained during surgery. The sonographic pattern for schistosomiasis periportal fibrosis is characteristic and is not mimicked by other hepatic diseases we have studied. Sonography agreed with pathology in 44 out of 50 patients. Schistosomiasis could be separated from cirrhosis, as well as from combined lesions. Where there was a discordance, we believe that sonography gave a more accurate diagnosis.
98 citations
92 citations
TL;DR: The period of exposure appeared to be the most important factor affecting the efficiency of these vapours rather than the dosage, and the declining order of susceptibility was Callosobruchus chinensis, Sitophilus granarius and Sitophils oryzae.
86 citations
TL;DR: In this paper, the authors used a coaxial cylinder viscometer to determine the viscosity of concentrated clarified and filtered banana juice at a wide range of temperatures (30 −70°C) and concentrations (20 −79·7°Brix).
82 citations
TL;DR: In this article, cyclopentanone reacts with arylidenemalononitriles to give dihydro-4,6-indenedicarboxylate derivative.
76 citations
Proceedings Article•
18 Jul 1989TL;DR: In this paper, the authors developed a real-time Arabic handwritten character recognition system, which assumes that characters result from a reliable segmentation stage, thus, the position of the character is known a priori.
Abstract: This paper considers the development of a real-time Arabic handwritten character recognition system. The shape of an Arabic character depends on its position in a given word. The system assumes that characters result from a reliable segmentation stage, thus, the position of the character is known a priori. Four different sets of character shapes have been independently considered. Each set is further divided into four subsets depending on the number of strokes in the character. The system has been heavily tested and the average recognition rate has been found to be 99.6% where all the misrecognized characters were actually written with little care. The system can be reliably used for the recognition of on-line handwritten characters entered via a graphic tablet. >
70 citations
TL;DR: In this paper, the authors focused on the critical analysis of all available drill hole data and seismic reflection records in the Abu Gharadig Basin area, which lies principally to the east of the Qattara Depression in the central portion of the Northern Western Desert of Egypt, and indicated that the basin is an elliptical, multicyclic, E-W trending structurally-controlled basin developed originally as a result of the deep crustal extensional tectonics that affected Northern Egypt during the Mesozoic Era.
11 Apr 1989
TL;DR: In this article, a simple efficient maximum power-point tracking technique is developed, which depends on a very simple criterion which is the measurement of the solar radiation level, and the control strategy is based on appropriate logic that compares the signs of dP/dt and dV/dt.
Abstract: It is noted that to overcome the problem of mismatch between solar cells and a given load, maximum power-point tracking should be used. A simple efficient maximum power-point tracking technique is developed. The connection strategy depends on a very simple criterion which is the measurement of the solar radiation level. The control strategy is based on appropriate logic that compares the signs of dP/dt and dV/dt. The proposed technique is applied to the cases of resistive load, resistive load with battery, and dynamic load. >
TL;DR: In this paper, the reactivity of alkylpyridine, pyridazine and pyrimidine derivatives towards aromatic aldehydes and arylidenemalononitrile is reported.
TL;DR: In this paper, N-substituted maleimides have been investigated as thermal stabilizers for rigid polyvinylchloride (PVC) at 180°C in air by measuring the rate of dehydrochlorination and the extent of discoloration of the polymer.
Abstract: N-substituted maleimides have been investigated as thermal stabilizers for rigid polyvinylchloride (PVC) at 180°C in air by measuring the rate of dehydrochlorination and the extent of discoloration of the polymer. The results reveal the higher stabilizing efficiency of these products relative to basic lead carbonate, dibutyl tin maleate, and cadmium-barium stearate stabilizers commonly used in industry. The induction period (Ts) increases as a function of the positive resonance effect of the substituents (+R). Moreover, the investigated stabilizers impart better color stability for the degraded samples as compared with the stearate stabilizer. The stabilizer efficiencies are attributed to their radical trapping potency which intervenes with the radical degradation process of PVC, while the good color stability is due to the ability of the stabilizer to interact with the conjugated double bonds formed on the PVC chains as a result of degradation. A mechanism illustrating the stabilizer's action is proposed.
N-substituierte Maleinimide sind thermische Stabilisatoren fur Hart-Polyvinylchlorid (PVC). Dies wurde durch Messung der Dehydrochlorierungsrate und des Ausmases der Verfarbung des Polymeren bei 180°C in Luft untersucht. Die Ergebnisse zeigen die hohere Stabilisierungswirkung dieser Produkte im Vergleich zu Stabilisatoren wie basisches Bleicarbonat, Dibutylzinnmaleat und Cadmium-Bariumstearat, die ublicherweise in der Industrie benutzt werden. Die Induktionszeit (Ts) steigt in dem Mase, in dem der positive Resonanzeffekt (+R) der Substituenten zunimmt. Ferner bewirken die untersuchten Stabilisatoren gegenuber Stearatstabilisatoren bessere Farbbestandigkeit der abgebauten Proben. Diese Stabilisatoreffektivitat ist darauf zuruckzufuhren, das der Stabilisator Radikale einfangen kann, die bei dem radikalischen Abbau von PVC entstehen. Die gute Farbstabilitat resultiert aus der Fahigkeit des Stabilisators, mit den konjugierten Doppelbindungen, die durch den Abbau des PVC in der Polymerkette entstehen, in Wechselwirkung zu treten. Ein Mechanismus fur die Wirkungsweise des Stabilisators wird vorgeschlagen.
TL;DR: In this article, the inhibition of corrosion of commercial 67/33 brass in 0.1m HCl acid solutions by some amino pyrazole derivatives was tested using polarization, capacitance and weight-loss measurements.
Abstract: The inhibition of corrosion of commercial 67/33 brass in 0.1m HCl acid solutions by some amino pyrazole derivatives was tested using polarization, capacitance and weight-loss measurements. The amino pyrazole derivatives were 3(5)-amino, 5(3)-phenyl pyrazole; 3(5)-amino, 5(3)[4--chlorophenyl] pyrazole; 3(5)-amino, 5(3)[4--methoxy phenyl]pyrazole; 3(5)-amino, 5(3)[4--methyl phenyl]pyrazole; 3(5)-amino, 5(3)-cyano pyrazole; and 3(5)-amino, 4-phenyl-5(3)-methyl pyrazole. The results showed that these compounds predominate as cathodic inhibitors and inhibition efficiencies up to 91% can be obtained. The inhibition was assumed to occur via chemisorption of the inhibitor molecules fitting a Temkin isotherm. The influence of the substituent group on the inhibition efficiency of the inhibitor was explained in terms of the density of the electron cloud on the pyrazole ring and the mode of adsorption. Although increase in temperature was found to decrease the corrosion in the absence of the inhibition, it increased in the presence of inhibitor, probably via desorption of the inhibitor molecules.
TL;DR: In this article, a pyridazinecarboxylate-3 d'ethyle reagit avec le soufre elementaire pour conduire a des thieno [3,4,d] pyridsazines, ces composes reagissent avec des composes ethyleniques deficients en electron, des phtalazines sont obtenues
TL;DR: In this article, an approximate method is utilized to investigate the hydrodynamic interactions between the members of an array of floating circular cylinders which occur when one member undergoes prescribed forced oscillations.
TL;DR: In this paper, the authors proposed the use of strength eccentricity as a more appropriate parameter to indicate the severity of inelastic torsional responses for asymmetrical structures, taking into account the uneven distribution of strength, rather than stiffness of the structure.
TL;DR: In this paper, the authors showed that 6-amino-5-cyano-4-aryl-2-methyl-4H-pyran-3-carboxylates 4 could be converted into 1,6-diazanaphthalene, pyrano-[2,3-c]pyrazole, isoxazolo[3,4-b]pyridine, Pyrano[2, 3-b]-polycyclic pyridine derivatives on treatment with malononitrile, hydrazine hydrate,
TL;DR: The corrosion inhibition of zinc in HCl solutions by several pyrazole derivatives was studied in this article, including 3(5) amino, 5(3) phenylpyrazole; 3( 5] amino, 3[4] [4] methylphenyl] pyrazide derivatives.
Abstract: The corrosion inhibition of zinc in HCl solutions by several pyrazole derivatives—namely, 3(5) amino, 5(3) phenylpyrazole; 3(5) amino, 5(3) [4′—methylphenyl] pyrazole; 3(5) amino, 5(3) [4′...
TL;DR: Dental casts of 243 preschool children, 129 males and 114 females, aged 2.5-5.5 years, were analysed for the presence of interdental spaces, mesiodistal crown diameters, intercanine width, intermolar width and arch length (circumference).
TL;DR: The author's experience with a modification of the standard fasciocutaneous forearm flap that involves the utilization of the fascial component of the flap sparing the skin of the forearm, which is closed as a longitudinal line.
Abstract: The unpleasant appearance of the donor site after harvesting a forearm flap limits its use in many centers. In this paper, the author records his experience with a modification of the standard fasciocutaneous forearm flap. Such modification involves the utilization of the fascial component of the flap sparing the skin of the forearm, which is closed as a longitudinal line. This fascial forearm flap (FFF) was used as a free flap in eight cases. All the flaps survived well, and the donor site appearance was excellent. The fascial forearm flap advantages and limitations are discussed with recommendations for further utilization of other fascial flaps.
TL;DR: Synthese a partir d'amino-5 arylazo-4 R-3 pyrazoles (R=methyl, amino ou hydroxy) respectivement par reaction avec le cinnamonitrile and par diazotation suivie de reaction with des composes a methylene actif as discussed by the authors.
Abstract: Synthese a partir d'amino-5 arylazo-4 R-3 pyrazoles (R=methyl, amino ou hydroxy) respectivement par reaction avec le cinnamonitrile et par diazotation suivie de reaction avec des composes a methylene actif
TL;DR: The 16/6 idiotype was a feature of chronic helminthic infection, but was not related to anti-DNA antibody levels or specificity, and the occurrence of nephritis as a complication of these infections was notrelated to the prevalence of the 16/ 6 idiotype.
TL;DR: The effects of cigarette smoking on male reproduction were studied through measuring the serum estradiol (E2), prolactin (PRL), and total testosterone (T).
Abstract: The effects of cigarette smoking on male reproduction were studied through measuring the serum estradiol (E2), prolactin (PRL), and total testosterone (T). Smoking men had higher levels of E2 and PRL but normal T compared to nonsmokers. Raised E2 and PRL may be among the mechanisms through which cigarette smoking impairs male reproduction.
TL;DR: A new algorithm for the fast computation of the discrete Fourier transform (DFT) is introduced, called the conjugate pair FFT (CPFFT), which is used to compute a length-2m DFT.
Abstract: A new algorithm for the fast computation of the discrete Fourier transform is introduced. The algorithm, called the conjugate pair FFT (CPFFT), is used to compute a length-2m DFT. The number of multiplications and additions required by the CPFFT is less than that required by the SRFFT algorithm.
TL;DR: In this paper, the influence of sea, ground, Nile and drinking waters on the microstructure of some hydraulic cements is investigated by means of X-ray diffraction analysis.
TL;DR: In this paper, cyclohexano-4H-pyrans were prepared by reaction of 1,1-dimethyl-3,5-diketo-cyclohexane 2 with cinnamonitriles 1 and converted into 2amino-4-aryl-1,4-dihydro-7,7-dimmethyl-5-oxocyclohexanopyridin-3-carbonitrile 7a, b.
Abstract: Cyclohexano-4H-pyrans could be prepared by reaction of 1,1-dimethyl-3,5-diketo-cyclohexane 2 with cinnamonitriles 1 and converted into 2-amino-4-aryl-1,4-dihydro-7,7-dimethyl-5-oxocyclohexanopyridin-3-carbonitrile 7a, b; 7,7-dimethyl-2,5-dioxo-4-phenyl-1,2,3,4-tetrahydro-cyclohexanopyridin-3-carbonitrile 8, 5-aryl-1,1-dicyano-2-phenyl-8,8-dimethyl-1,2,3,4,6,7,8,9-octahydro-3-azaacridin-4,6-dione 12a, b and 2-thioxo-4-amino-5-aryl-3-benzoyl-2,3-dihydro-9,9-dimethylcyclohexano-[g]-4H-pyrano[2,3-d]pyrimidin-7-one 14a, b.
TL;DR: The Abu Roash district is located 10 km to the southwest of Cairo, and is geologically significant because of its surface exposure of Upper Cretaceous rocks as discussed by the authors, which can be used as a stratigraphic and structural model for the Western Desert.
TL;DR: In this article, the ionization constants of the formazans as well as the formation constants of their lanthanum complexes were studied potentiometrically m solution by Sarin's method.