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Ibrahim, N. M., E. A. Eweis, H. S. El-Beltagi, and Y. E. Abdel-Mobdy, "The Effect of Lead Acetate Toxicity on Experimental Male Albino Rat", Biological Trace Element Research, vol. 144, pp. 1120-1132, 2011. Abstract

The toxic effect of Pb ion (lead acetate) was investigated using male albino rats, which was ingested at 1/20, 1/40, and 1/60 sublethal doses. Relative to normal control, the ingestion of Pb2+ induced significant stimulation in ALT and AST activity. In addition, total soluble protein and albumin contents of plasma were decreased, while the content of globulin was changed by the Pb2+ treatments. The cholinesterase activity was inhibited, but the activities of alkaline and acid phosphates as well as lactate dehydrogenase were stimulated as a result of lead acetate intoxication. These observations were gradually paralleled across the experiment dose of the three doses of intoxicated Pb2+. In the case of blood picture, Pb2+ ingestion significantly reduced the contents of hemoglobin and RBC count of intoxicated rat’s blood, while the plasma levels of T3 and T4 and blood WBC count were insignificantly decreased or unchanged. All results of the present study showed that the Pb2+ ingestion was more effective in the case of the high dose (1/20 LD50) than that of the low dose (1/60 LD50) ingestion relative to the normal healthy control. The results of the present work advice the need to avoid exposure of humans to the lead compound to avoid injurious hazard risk.

Saad, A. M., M. M. Bakr, I. M. Azzouz, and A. M. T. H. Kana, "Effect of temperature and pumping power on the photoluminescence Properties of type-II CdTe/CdSe core-shell QDs", Applied Surface Science, vol. 257, issue 20, 2011. cu_pdf.pdf
Saad, A. M., M. M. Bakr, I. M. Azzouz, and A. M. T. H. Kana, "Effect of temperature and pumping power on the photoluminescence Properties of type-II CdTe/CdSe core-shell QDs", Applied Surface Science, vol. 257, issue 20, pp. 8634–8639, 2011. Abstract

CdTe/CdSe core-shell QDs type II was prepared by two steps synthetic process and embedded in polymer host. Emission in the NIR region was recorded. The effect of Ar laser excitation at different powers on the optical properties of the prepared QDs is studied at different temperatures (300–10 K). Amplified spontaneous emission is observed at room temperature and at 10 K. Also, lifetime measurement of prepared QDs was documented using N2-laser.

Robaa, S. M., "Effect of Urbanization and Industrialization Processes on Outdoor Thermal Human Comfort in Egypt", Atmospheric and Climate Sciences, vol. 1, pp. 100-112, 2011. AbstractCU-PDF.pdf

Detailed studies on the effect of urbanization and industrialization processes on outdoor thermal human com- fort in Greater Cairo region, Egypt have been performed in this study. Four different districts in Greater Cairo region have been selected to represent rural, suburban, typical urban and industrial areas. The data of surface dry, wet bulb temperatures and wind speed for two different periods represent non-urbanized and urbanized periods have been used. Discomfort indices for the two periods have been calculated for the four districts.
The study revealed that urbanization and industrialization processes have resulted in the distinctly modification of human comfortable at all districts. The feeling of quite comfortable reduced from the old non-urbanized period to the recent urbanized period at the four districts. During the recent urbanized period, the rural area has the highest total number of quite comfortable hours while both urban and industrial areas have the lowest total number of hours. The serious hot uncomfortable didn’t occur at all districts during the old non-urbanized period while during the recent urbanized period, all people had felt extreme serious hot uncomfortable only at urban and industrial areas. It could be concluded that the urbanization and industrialization processes cause increase of human serious hot uncomfortable feeling which in turn leads to more hindering for the human activities while the rural conditions leads to optimum weather comfort for further and more human activities.

Klimpel, S., F. Abdel-Ghaffar, K. A. S. Al-Rasheid, G, K. Fischer, B. Strassen, and H. Mehlhorn, "The Effects of Different Plant Extracts on Nematodes", Parasitology Research, vol. 108, issue 4, pp. 1047-1054, 2011. Abstract

The anthelminthic efficacy of some differently obtained extracts of several plants was tested in vivo in laboratory animals and in vitro. The extracts were obtained by ethanolic, methanolic, aqueous, or chloroform, respectively, acetonitrile polyethylenglycol (PEG) and/or propylencarbonate (PC) elution at room temperature or at 37°C. The plants used were bulbs of onions, garlic, chives, coconut, birch tree, ananas, cistrose, banana, chicory, date palm fruit, fig, pumpkin, and neem tree seeds. The worm systems tested both in vivo and in vitro were Trichuris muris and Angiostrongylus cantonensis but only in vivo Toxocara cati. The tests clearly showed that the different extraction methods eluted different components and different mass amounts, which had different efficacies against the above-cited worms. In vitro effects against A. cantonensis and T.muris were best with aqueous extracts, followed by chloroform extracts. The other plant extracts showed only low or no effects on A. cantonensis in vitro. In the case of T. muris, best results were obtained in vivo and in vitro with PEG/PC extracts of the onion followed by the aqueous extract of coconut. The complete elimination of worms in the in vivo experiments with T. muris was obtained when infected mice were treated with a 1:1 mixture of extracts of coconut and onion being produced by elutions with a mixture of 1:1 PEG and PC and fed daily for 8 days. T. cati in a naturally infected cat was eliminated by daily oral application of 6 ml coco’s fluid for 5 days. This study shows that a broad spectrum of plants has anti-nematodal activities, the intensity of which, however, depends on the mode of extraction. This implicates that, if results should be really comparable, the same extraction methods at the same temperatures have to be used. Furthermore, efficacy in in vitro systems does not guarantee as good—if at all—efficacy in vivo.

Soaud, A. A., F. A. H. Darwish, M. E. Saleh, K. A. El-Tarabily, M. Sofian-Azirun, and M. MotiorRahman, "Effects of Elemental Sulfur, Phosphorus, Micronutrients and ParacoccusVersutus on Nutrient Availability of Calcareous Soils", Australian Journal of Crop Science (AJCS), vol. 5, issue 5, pp. 554-561, 2011. Abstract

This study was carried out in the laboratory to investigate the effects of elemental sulfur (S-0), Paracoccus versutus (Pv), phosphorus (P) and micronutrients (DTPA extractable Fe+Mn+Zn) both singly and combined on nutrient availability of calcareous soils. Soils were collected from Al Semaih, Al Dhahrah and Melaiha in United Arab Emirates (UAE) and all soils were incubated at 40 +/- 2(0)C for 32, 64, 96 and 128 days. Soil pH dropped and S concentration increased significantly with the addition of S-0 alone or in combination with Pv, P and micronutrients in all types of soils. Elemental S application considerably increased the electrical conductivity (EC) of Al Semaih and Melaiha soils but reduced EC in Al Dhahrah soils at 128 days after incubation (DAI). Phosphorus availability was higher and prolonged with the application of S-0 along with P. Zinc (Zn) and manganese (Mn) availability did not increase with the individual application of S-0 or P. Inoculation of Pv influenced S and P availability but had no effect on iron (Fe), Mn and Zn. The study suggests that S-0 is an effective agent for the amendment of sandy calcareous soils. Application of S-0 accompanied with Pv, P and micronutrients are essential for nutrient availability in calcareous soils.

Fekry, A. M., "Electrochemical Corrosion Behavior of Magnesium Alloys in Biological Solutions", Magnesium Alloys Corrosion and Surface Treatments, 2011. intech-electrochemical_
Kassab, M. F. 1and K., "Evaluation of the Photostability and Photodynamic Efficacy of Rose Bengal Loaded in Multivesicular Liposomes", Tropical Journal of Pharmaceutical Research, vol. 10, issue 3, 2011. Abstractpr11038.pdf

Purpose: Rose Bengal (RB) is a potential photodynamic sensitizer in anticancer therapy. The purpose of this study was to prepare multivesicular liposomes (MVL) loaded with RB to enhance its photostability and intracellulaer photodynamic efficacy.

I., E., "Exponentiated Modified Weibull Distribution", Economic Quality Control, vol. 26, issue 2, pp. 189–200, 2011. CU-PDF
Frey, C. M., E. Parlow, R. Vogt, M. Harhash, and M. A. M. Wahab, "Flux Measurements in Cairo", Int. J. Climatol, vol. 4, pp. 2635-2660, 2011. AbstractCU-PDF.pdf

Cairo Air Pollution and Climate (CAPAC) is dedicated to the understanding of the urban energy balance inCairo, Egypt, through measurements from space and at ground stations. The in situ measurements will provide a focused insight into three carefully chosen microclimates (urban, suburban-agriculture, and suburban-desert) and provide at the sametime ground-truth data for satellite image analysis, which will expand the acquired knowledge into the spatial domain. Insitu measurements were made during a field campaign in Greater Cairo from November 2007 to February 2008. In thisstudy, the dataset of the CAPAC measurement campaign will be presented and analysed in terms of use for a remote sensingstudy. Measured variables complied with our expectations. The urban area featured a distinct nocturnal heat island. Duringthe day the choice of reference station was responsible for the magnitude of the heat island. The diurnal cycle of radiativetemperature at the suburban-desert station clearly exceeded the one at the urban station, thus the urban setting seemed tohave a better heat storage than the suburban-desert. The stations also determined the partitioning of the turbulent heat fluxes.
While in Cairo and at the suburban-desert station most of the available energy was partitioned into the sensible heat flux,the suburban-agricultural station maintained a high latent heat flux. The radiation and soil heat flux measurements provedto be applicable for comparison with remotely sensed data. However, the analysis of the turbulent heat fluxes showedthat several constraints exist: measured fluxes tend to underestimate the actual flux and directional effects complicate theinterpretation. An energy balance closure and footprint modelling is necessary to compare measured fluxes with satelliteimage retrieved products. Finally, turbulent fluxes are time averages, which is contrary to the remote sensing principle. Consequently, a direct use is problematic.

Abdelaziz, W. S., "High gain predictions for Ni-like Gd ion", Optics Communications, vol. 284, issue 12, pp. 2859-2862, 2011. AbstractCU-PDF.pdf

Atomic structure data and effective collision strengths for 1s22s22p63s23p6 3d10and 54 ?ne-structure levels contained in the con?gurations 1s22s22p63s23p63d9 4l (l=s, p, d, f) for the nickel-like Gd ion. These data are used in the determination of the reduced population for the 55 ?ne structure levels over a wide range of electron densities (from 1021 to 1023) and at various electron plasma temperatures. The gain coef?cient for those transitions with positive population inversion factor are determined and plotted against the electron density.

Gadallah, A. - S., and R. Michalzik, "High-Output-Power Single-Higher-Order Transverse mode VCSEL With Shallow Surface Relief", Ieee Photonics Technology Letters, vol. 23, issue 15, 2011. AbstractCU-PDF.pdf

We report high-power single-higher-order transverse mode emission of a large-area oxide-confined rectangular-shaped vertical-cavity surface-emitting laser (VCSEL) with a multispot shallow surface relief. Both a record-high output power of 12 mW and a record-low differential series resistance of 18 ohms are achieved. Stable single-higher-order transverse mode emission with a sidemode suppression ratio (SMSR) exceeding 35 dB is maintained up to thermal rollover. Single-polarization lasing along the major axis is achieved with 27.5-dB spectral orthogonal polarization suppression ratio at thermal rollover. Measurements of near- and far-field intensity profiles of the higher-order mode are also presented.

Kassab, A. N., and A. E. Kharbotly, "Management of ear lobule keloids using 980-nm diode laser", Eur Arch Otorhinolaryngol, vol. 269, issue 2, pp. 419-23, 2011. Abstractcu_pdf.pdf

The objective of the study was to evaluate the 980-nm diode laser in conjunction with corticosteroids in the treatment of ear lobule keloids. Several methods have been described for the treatment of keloid scars, but none of them have been 100% successful.

Mohammed, H. S., H. A. S. ezz, Y. A. Khadrawy, and N. A. Noor, "Neurochemical and Electrophysiological Changes Induced by Paradoxical Sleep Deprivation in Rats", Behavioural Brain Research, vol. 225, pp. 39-46, 2011. AbstractCU-PDF.pdf

Concentrations of amino acid neurotransmitters were assessed in the hippocampus and cortex using HPLC. Control data showed slight differences from normal animals in the delta, theta and alpha waves while an increase in the beta wave was obtained. After 24 h of PSD, delta relative power increased and the rest of EEG wave’s power decreased with respect to control. After 48 h and 72 h the spectral power analysis showed non-significant changes to control. The amino acid neurotransmitter analysis revealed a significant increase in cortical glutamate, glycine and taurine levels while in the hippocampus, glutamate, aspartate, glutamine and glycine levels increased significantly. Both the waking EEG and neurotransmitter analyses suggest that PSD induced neurochemical and electrophysiological changes that may affect brain proper functionality. © 2011 Elsevier B.V. All rights reserved.

Elfeky, S. A., "Novel Boronic Acid-Based Fluorescent Sensor for Sugars and Nucleosides", Current organic synthesis, vol. 8, issue 6, pp. 872-880, 2011. AbstractCU-PDF.pdf

Sugar and nucleoside identifications are important for the detection and treatment of dangerous diseases. In this study, a fluorescent boronic acid (3-(5-(dimethylamino) naphthalene-1-sulfonamido) phenyl) boronic acid (DNSBA) was bound to a diol quencher via a boronic ester linkage, and fluorescence recovery upon exposure to saccharides and nucleosides was demonstrated. Further, we successfully detected sugars and nucleosides in buffer systems. DNSBA expresses selectivity toward adenosine, fructose, sorbitol, and tartaric acid. Our investigations into the effects of pH on sensor sensitivity revealed that changes between the neutral and anionic forms of the boronic acid group, induced at high pH and/or in the presence of sugars or nucleosides, induce visible/optimal changes in DNSBA. DNSBA is responsive at pH = 8.21 whereas acidic media do not exhibit sensitivity. DNSBA can thus be useful in clinical applications as a novel sensor for sugars and nucleosides.

Sweilam, N. H., W. Mahmoud, and E. K. Rawy, "Numerical Study of Some Systems of Linear Algebraic Equations with Noise Related to Boundary-value Problems for Laplace", Studies in Nonlinear Sciences 2 (2): 60-69 (2011), 2011. AbstractCU-PDF

We investigate two stable methods for solving the system of linear algebraic equations arising
from plane, singular boundary-value problems for Laplace’s equation for rectangular domains [1, 21]. The
dynamical systems method and the variational regularization method are applied to derive stable solutions
for these systems, and the results are compared with those obtained from the QR-factorization technique
contaminated with noise. The results put in evidence the difficulties that may arise from the use of the QRfactorization
method due to instability.

Khedr, A., V. Papadakis, P. Pouli, D. Anglos, and M. A. Harith, "The Potential use of Plume Imaging for Real-Time Monitoring of Laser Ablation Cleaning of Stonework", Applied Physics, vol. 105, issue 2, pp. 485, 2011. AbstractCU-PDF.pdf

In this work, the potential of plume imaging was investigated as a real-time monitoring technique for the control of the laser cleaning process in cultural heritage objects with emphasis on encrusted stonework. Optical pulses generated by Nd:YAG laser were used to remove a high absorbing layer of crust from the surface of a lower absorbing marble substrate. Two regimes of operation have been employed for laser cleaning test, Q-switched ns mode, and short free running ?s mode. Laser induced breakdown spectroscopy (LIBS) was also employed to study the stratigraphy of the cleaned surfaces, and thus to confirm the validity of the suggested monitoring technique.

Asklany, S. A., K. Elhelow, I. K. Youssef, and A. M. El-wahab, "Rainfall Events Prediction using Rule-based Fuzzy Inference System", Journal of Atmospheric Research, vol. 101, pp. 228–236, 2011. AbstractCU-PDF.pdf

We are interested in rainfall events prediction by applying rule-based reasoning and fuzzy logic. Five parameters: relative humidity, total cloud cover, wind direction, temperature and surface pressure are the input variables for our model, each has three membership functions. The data used is twenty years METAR data for Cairo airport station (HECA) [1972–1992] 30° 3′ 29″ N, 31° 13′ 44″ E. and five years METAR data for Mersa Matruh station (HEMM) 31° 20′ 0″ N, 27° 13′ 0″ E. Different models for each station were constructed depending on the available data sets. Among the overall 243 possibilities we have based our models on one hundred eighteen fuzzy IF–THEN rules and fuzzy reasoning. The output variable which has four membership functions, takes values from zero to one hundred corresponding to the percentage for rainfall events given for every hourly data. We used two skill scores to verify our results, the Brier score and the Friction score. The results are in high agreements with the recorded data for the stations with increasing in output values towards the real time rain events. All implementation are done with MATLAB 7.9.

Hafez, Y., "Relationship Between Geopotential Height Anomalies Over NorthAmerica and Europe and the USA Landfall Atlantic Hurricanes Activity", Journal of American Science, 2011. Abstract

The present paper investigates the relationship between geopotential height anomalies at level of 500 hpa over North America and Europe, and the USA landfall Atlantic hurricanes activity. The decadal data of the number of hurricanes by category which stroked the mainland USA for each decade through the period (1851-2006) are used through the present study. The daily NCEP/NCAR reanalysis data composites for geopotential height at 500 hpa level over North America and Europe for the period of (1949-2006) are used too. Hurricane datasets and anomalies in geopotential height are analyzed and correlated together. The results revealed that there are significant positive correlations between the anomalies in geopotential height over North America and East Europe simultaneously, and existence of Atlantic hurricanes of category 3 that strike USA. In addition to that, significant positive correlations between the anomalies in geopotential height over North America and existence of major hurricanes (category 3, 4 and5) that landfall USA is found too. However, significant negative correlations between the anomalies in geopotential height over North Atlantic and existence of all USA Landfall Atlantic Hurricane categories are existed else category 1. In general one can conclude that anomalies in geopotential height at 500 hpa level over North America and Europe are control the USA landfall Atlantic hurricanes activity.[Yehia Hafez. Relationship Between Geopotential Height Anomalies Over North America and Europe and The USA Landfall Atlantic Hurricanes Activity.

Shanan, N. T. A., and A. S. Soliman, "Response of Snapdragon Plants to Pinching and Growth Retardants Treatments", American-Eurasian Journal of Sustainable Agriculture, vol. 5, issue 2, pp. 150-157, 2011. CU-PDF
Abdelhalim, M. A. K., M. M. Mady, and M. M. Ghannam, "Rheological and Dielectric Properties of Different Gold Nanoparticle Sizes", Lipids in Health and Disease, 2011. AbstractCU_PDF.pdf

Gold nanoparticles (GNPs) have found themselves useful for diagnostic, drug delivery and biomedicine applications, but one of the important concerns is about their safety in clinical applications. Nanoparticle size has been shown to be an extremely important parameter affecting the nanoparticle uptake and cellular internalization.
The rheological properties assume to be very important as it affects the pressure drop and hence the pumping power when nano-fluids are circulated in a closed loop. The rheological and dielectric properties have not been documented and identified before. The aim of the present study was to investigate the rheology and the dielectric properties of different GNPs sizes in aqueous solution.
Methods: 10, 20 and 50 nm GNPs (Product MKN-Au, CANADA) was used in this study. The rheological parameters were viscosity, torque, shear stress, shear rate, plastic viscosity, yield stress, consistency index, and activation energy. These rheological parameters were measured using Brookfield LVDV-III Programmable rheometer supplied with temperature bath and controlled by a computer.
The shear stress and shear rate of GNPs have shown a linear relationship and GNPs exhibited Newtonian behaviour. The GNPs with larger particle size (50 nm) exhibited more viscosity than those with smaller particle sizes (10 and 20 nm). Viscosity decreased with increasing the temperature for all the examined GNP sizes. The flow behaviour index (n) values were nearly ≤ 1 for all examined GNP sizes.
Dielectric data indicated that the GNPs have strong dielectric dispersion in the frequency range of 20-100 kHz. The conductivity and relaxation time decreased with increasing the GNP size. This study indicates that the GNP size has considerable influence on the viscosity of GNPs. The strong dielectric dispersion was GNP size dependent.
The decrease in relaxation time might be attributed to increase in the localized charges distribution within the medium confirmed by the conductivity data. This study suggests that further experiments are required to be done after the administration of GNPs through different routes in rats in vivo.
Keywords: Gold nanoparticles; Rheological parameters; Size; Temperature; Dielectric; Conductivity.

HA, M., A. E. - A. AA, S. N, R. N., and A. RA, Role of HFE gene mutations on developing iron overload in beta-thalassaemia carriers in Egypt., , vol. 17, issue 6, 2011. Abstractcu_pdf.pdf

A case-control study aimed to determine the prevalence of C282Y, H63D and S65C mutations of the HFE gene in beta-thalassaemia carriers and investigate their influence on iron absorption. A total of 41 beta-thalassaemia carriers and 40 control subjects without haemoglobinopathies were screened for the C282Y, H63D and S65C mutations by polymerase chain reaction-restriction fragment-length polymorphism. The iron status in these subjects was studied and correlated with the HFE gene mutations. H63D, S65C and C282Y allele frequencies were 30.5%, 13.4% and 7.3% respectively in beta-thalassaemia carriers and 10.0%, 2.5% and 0.0% respectively in the control group. Compound heterozygosis was found in 10 carriers (24.4%). The transferrin saturation level was high in compound heterozygote cases. Our study has shown that the HFEgene mutations are common in Egypt among beta-thalassaemia carriers compared with normal controls.

Hilali, M., M. El-seify, A. Zayed, A. El-morsey, and J. P. Dubey, "Sarcocystis dubeyi (Huong and Uggla, 1999) Infection in Water Buffaloes (Bubalus bubalis) from Egypt", J. Parasitol., 2011. Abstract

Water buffaloes (Bubalus bubalis) are intermediate hosts for 4 species of Sarcocystis, i.e., Sarcocystis fusiformis and Sarcocystis buffalonis with cats as definitive hosts; Sarcocystis levinei with dogs as definitive hosts; and Sarcocystis dubeyi with an unknown definitive host but thought to be zoonotic. Currently, the latter species has been identified with certainty only from Vietnam. In the present study, sarcocysts of S. dubeyi are reported in 11 (30%) of 35 Egyptian water buffaloes from which the esophageal muscles were examined histologically. Sarcocysts were microscopic, measuring 180-250 X 70-110 urn in size. Ultrastructurally, the sarcocyst wall was 3.5-6.5 urn thick and had palisade-like villar protrusions which give it a striated appearance. The villar protrusions contained micro tubules that were distributed along the whole villus. This is the first report of S. dubeyi from water buffaloes in Egypt.

Ahmed, F. A., M. M. Rashed, N. S. A. M. Khalil, and M. A. A. M. Hashem, "The Scavenging Capacity and Synergistic Effect Of Some Natural Antioxidants Mixtures On The Dpph? Free Radical", Advances in Food Sciences, 2011. Abstract

The biological activity of the natural antioxidant vitamin C can be enhanced by the presence of some other active natural antioxidants, such as gallic and tannic acid. Since many of these natural antioxidants are consumed sometimes together in foods, the potency for synergistic interactions is high in the human diet.

Ahmed, F. A., M. M. Rashed, N. S. A. M. Khalil, and M. A. A. M. Hashem, "The Scavenging Capacity And Synergistic Effect Vitamin C, Gallic Acid And Tannic Acid On Ccl4-Induced Acute Hepatic Injury In Experimental Rats", Advances in Food Sciences, 2011. Abstract

The biological activity of the natural antioxidant vitamin C can be enhanced by the presence of some other active natural antioxidants, such as gallic and tannic acid. Since many of these natural antioxidants are consumed together in foods, the potency for synergistic interactions is high in the human diet. In the current study, the hepatoprotective activity of the natural antioxidants against CCl4- induced acute hepatic injury by using rats (male albino) was investigated.