Calcium hydroxyapatite, HA, (Ca 10 (PO 4 ) 6 (OH) 2 ) bioceramics, owing to their similarity with the human bone and dentin minerals, attract significant interest for orthopaedic and dental applications. Biological apatites, on the other hand, are carbonate substituted and calcium-deficient. Biomimetic coating of titanium and related alloys with carbonated apatitic calcium phosphate is an important area of research in implantology. While this paper specifically refers to coating Ti-6Al-4V, (TAV) the obtained results are valid with other related alloys as well.An attempt was made in the current research to accelerate the biomimetic coating process through precalcification of the alkali and heat treated alloy. The precalcification resulted in a homogenous layer of calcium precursors on the surface of the alloys. Such precursors accelerated the biomimetic deposition of carbonate hydroxyapatite (CHA) coat resembling that of the biomineral apatite upon soaking in Kukubo corrected simulated body fluid (1.5 c-SBF). The development of coats on Ti-6Al-4V surfaces were assessed by step by step diffuse reflectance infra-red spectroscopy and scanning electron microscopy.The essential information of biodeposition was obtained by following the uptake or release of calcium and inorganic phosphorus, Ca, iP, ionic species biochemically and mirrored by parallel electrical conductivity measurements of the soaking solutions.

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Ginkgo biloba extract has been therapeutically used for several decades to increase peripheral and cerebral blood flow as well as for the treatment of dementia. The extract contains multiple compounds such as flavonoids and terpenoids that are thought to contribute to its neuroprotective and vasotropic effects. In this study, we investigated the effect of prolonged administration of EGb 761, up to 10 weeks, on mammalian retina using Fourier transform infrared spectroscopy (FTIR). Two main groups were involved in this study: the normal group (n = 10); and EGb-administrated group (n = 50) that received-orally-a dose of 40 mg/kg/day EGb 761. The results demonstrated that EGb administration was associated with different beneficial effects on the retinal constituents especially the underlying amide I protein secondary structure components as well as the NH-OH region. It concluded that the optimum daily administration period of EGb (40 mg/kg) for ophthalmic applications that targeting the retina ranges from 5 to 8 weeks.

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Arab Abu Saed area in Giza governorate, south to Cairo contains more than 228 clay brick kilns represent the largest cluster of brickworks in Egypt. Burning of Heavy Fuel Oil (HFO) in such kilns is the main source of air pollution in the surrounding locations. In this study, investigation of switching the fuel used in brick kilns from (HFO) to Natural Gas (NG) is carried out and the pollution loads are assessed in both cases. In addition, two Gaussian dispersion plume models are employed to estimate the concentration of primary pollutants; PM 10 , SO 2 , and NO 2 at seven locations in the vicinity of Arab Abu Saed to determine the most adversely affected locations. Statistical analysis is applied to evaluate the correlation and conformity of the results of both models. Results show that using of NG leads to a significant reduction of pollution loads of PM 10 , SO 2 and NO 2 reaches 96%, 72%, and 24% respectively. In addition, the reduction of naturally occurring radionuclides in air is analyzed. Activity concentrations of Ra-226, Th-232 and K-40 in Bq/l for HFO were measured using HPGe detector for six HFO samples. Exposure due to air submersion of naturally occurring radionuclides in the study area leads to annual equivalent dose ranged between 2.16 mSv/y (received by Uterus) and 14 mSv/y (received by skin), and average effective dose 2.65 mSv/y which represent valuable exposure.