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Background: The quality assurance of 3D treatment planning system (TPS)will be investigated by different things such as beam configuration, dose calculation and plane evaluation which uses dose volume histogram analyzes. Material and method: the study was performed by XIO TPS (version 4.3.3) available at South Egypt Cancer Institute (SECI). This TPS employs two different 3D algorithms (Clarkson (CLK) and Fast Fourier Transform Convolution (CON)). Relative dose calculation (RDC) in terms of percentage depth dose (PDD) and off axis beam profiles (OAR) and absolute dosecalculation (ADC) in terms of dose and output factor were used and compared with the measured one using ionization chambers with water or solid phantoms in medical linear accelerator linac (Siemens Mevatron MD2).Two photon energies 6MV and 15MV were studied using field sizes of 10×10cm2 and 25×25cm2 for open field. Results: The OAR and PDD are divided into regions each of these having a tolerance limit of the accuracy acceptable. The large point of deviation appeared in field size 25×25cm2 at energy 15MV in outer regionδ4 of OAR. This region recorded the largest deviation than the others regions. In PDD curves haven’t any deviation.Larger deviations were observed with CLK algorithm compared to CON algorithm. 20 points out of criteria were observed in the RDC of a large field size 25×25cm2, while 16 points were out of criteria in the field size 10×10cm2. Conclusion: This work presents a feasibility and performance of quality assurance tasks the TPS for external photon beam

Radioactive pollution comes on the top of pollution types that affect human life directly through damaging the human genome or indirectly via his food web. The current study focused on the evaluation of radiation effects of Assiut Thermal Power Plant (ATPP) ashes on two crop plants, potato and squash, in terms of morphological and molecular levels. More particularly, the specific activity concentrations were measured in Bq/kg, of the 238U (226Ra) and 232Th series, and 40K-isotope for the untreated soil sample (control) and ATPP ash sample (represents the radioactive source with 100% concentration). Different concentrations of ATPP ash (0, 2, 4, 6 and 8%) were mixed with soil sample to study the effect of radioactively contaminated soil on potato and squash plants. The results of the present investigation revealed that the morphological characteristics of both potato and squash plants were changed, which reflected a steep regression in the values of all vegetative growth and yield traits. The alterations of the characteristic values were directly proportional to the radioactive ash concentration in the soil. In the same context, the molecular evaluation using PCR-based markers, e.g., ISSR and SCoT helps in understanding and explaining experimental observations at morphological level. ISSR/SCoT bands confirmed the toxicity and mutagenicity of radioactive ash samples at their present dose on both potato and squash plants. The present findings clearly explained the morphometric and genetic abnormalities in two of the main consumed crops by a human. Thus, the green area around the ATPP may disappear in the future due to increasing the pollution in terms of the radioactive component that directly attached to plants or indirectly by mixing with soil.

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Background: retinoids are known to be essential for the normal development of diverse embryonic structures including eye. The ventral region of the optic cup of the chick embryo undergoes a complex process of differentiation leading to the formation of different eye structures. Signaling molecules such as retinoic acid (RA) have been implicated in the regulation of these phenomena. Purpose: the present study aims to explore the differential effect of different concentrations of exogenous RA during morphogenesis of the eye of the chick embryo. Materials and methods: fertilized eggs of Gallus domesticus were injected with a single dose of 0.5 µg, 1 µg or 2 µg of RA dissolved in 1 µl od dimethylsulphoxid (DMSO). Injections were carried out after three days of incubation. Results: The excess of exogenous RA caused several malformations in the eye of the embryo. These malformations included disappearance of one eye, bilateral exophthalmos, lens dysgenesis, retinal folds and chorioretinal coloboma. Data of the present study showed highly significant association between the presence of RA and the appearance of deformed eye in embryos. Conclusion: The explanation of these deformities was based on the disturbance of normal pattern of expression of genes concerned with the process of morphogenesis. Where the exogenous RA caused overexpression of some genes resulted in several malformations and disturbance of pattern formation in the eye of the developing embryo.

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Thermal analysis of chalcogenide glass similar to other materials is of great importance in order to increase the knowledge about its phase transitions, thermal stability, etc. The current study reports on the thermal kinetics of melt-quenched Zn5Se95 chalcogenide glass using differential thermal analysis (DTA) techniques under non-isothermal conditions. The glass-forming ability (GFA) and the relation between the glass transition and onset crystallization temperatures are found to show a linear behavior. In addition, Moynihan et al. Kissinger’s, and other approaches of Johnson-Mehl-Avrami utilized to determine the activation energy of the amorphous-crystalline and glass transition. It is found that the glass transition process cannot be concluded in terms of single activation energy, and that variation with the extent of conversion was analyzed using various iso-conventional methods. Therefore, the observed change of the activation energy throughout the glass transition reveals that the transition from amorphous to the supercooled liquid phase of Zn5Se95 glass is a complex process. The crystallization process at different heating rates is simulated using the M
alek method, and Sest
akeBerggren SB(M,N) model, in which the SB model show fairly good matching with the experimental DTA data. Moreover; the fragility index is a measure of the GFA of Zn5Se95 chalcogenide glass, which has been estimated using the glass transitions and activation energy values. We have found that the fragility index of Zn5Se95 glass values in between ~13 and 30, depending on the heating rate, revealing that the synthesized glass is a strong liquid with excellent GFA.

The significant use of copper oxide nanoparticles (CuO NPs) has generated worries over their impacts on the ecosystem and human health due to their release from numerous products to the environment. The Solanum nigrum L. is recognized as a phytoremediation plant and may survive within the excessive metal-stressed surroundings. Five CuO NPs levels were evaluated for their impacts on the callus of S. nigrum. Fresh, dry weight, water content, free amino acids, and potassium content of callus cells were significantly decreased due to the impact of CuO NPs. We also observed increased levels of malondialdehyde, bound phenolic compounds, soluble carbohydrates and enzymatic activity of peroxidase, and polyphenol oxidase in callus cells supplying conditions for the lowering of oxidative stress triggered by CuO NPs. Phenylalanine ammonia lyase, soluble proteins and free phenolic compounds in callus cells were increased under 50, 100 and 150 mg/L CuO NPs and were significantly decreased in most cases by the application of the highest concentration (200 mg/L) of CuO NPs. The catalase activity in calli didn’t clearly change via CuO NPs stress. Further, Cu accumulation in the callus was increased with increasing levels of CuO NPs in the medium (50–200 mg/L), as evidenced through 10.3, 17.0, 20.9 and 40.4-fold, respectively, as compared with the control. The FT-IR analysis showed alterations in most macromolecules such as phenolic compounds, lipids, proteins, carbohydrates, cellulose, and hemicellulose in callus cells-treated with CuO NPs. From these results, we can conclude that S. nigrum plants can be used to remediate the medium contaminated with CuO NPs because the plant can accumulate the metal and has a response to defend itself from the metal stress.

This article deals with investigation of fine-scale precipitation in Al-Mg-Zn alloys with compositions of Al - 2 at% Mgx at% Zn, (x = 1.8, 2 and 4.2). The precipitates morphology was examined by scanning electron microscope (SEM) and correlated with the microhardness (HV) and differential scanning calorimetry (DSC) of the specimens. The precipitates are characterized as ’ (MgZn2) and  (MgZn2) phases of hexagonal structure of the same composition with a slight difference in lattice parameters. In addition, T-phase pf composition (Mg32 (Al, Zn)49) having a cubic crystal structure. Owing to the determined activation energies of the precipitates, the kinetics associated with their nucleation and growth can be characterized. The thermal energy acquired during aging leads to the agglomeration of precipitates to or larger particle sizes.