Objectives Dental implant is a revolution in dentistry; some shortages are still a focus of research. This study use long duration of radiofrequency (RF)–magnetron sputtering to coat titanium (Ti) implant with hydroxyapatite (HA) to obtain a uniform, strongly adhered in a few micrometers in thickness. Materials and Methods Two types of substrates, discs and root form cylinders were prepared using a grade 1 commercially pure (CP) Ti rod. A RF–magnetron sputtering device was used to coat specimens with HA. Magnetron sputtering was set at 150 W for 22 hours at 100°C under continuous argon gas flow and substrate rotation at 10 rpm. Coat properties were evaluated via field emission scanning electron microscopy (FESEM), scanning electron microscopy–energy dispersive X-ray (EDX) analysis, atomic force microscopy, and Vickers hardness (VH). Student’s t-test was used. Results All FESEM images showed a homogeneous, continuous, and crack-free HA coat with a rough surface. EDX analysis revealed inclusion of HA particles within the substrate surface in a calcium (Ca)/phosphorus (P) ratio (16.58/11.31) close to that of HA. Elemental and EDX analyses showed Ca, Ti, P, and oxygen within Ti. The FESEM views at a cross-section of the substrate showed an average of 7 µm coat thickness. Moreover, these images revealed a dense, compact, and uniform continuous adhesion between the coat layer and the substrate. Roughness result indicated highly significant difference between uncoated Ti and HA coat (p-value < 0.05). A significant improvement in the VH value was observed when coat hardness was compared with the Ti substrate hardness (p-value < 0.05). Conclusion Prolonged magnetron sputtering successfully coat Ti dental implants with HA in micrometers thickness which is well adhered essentially in excellent osseointegration.
In present study, an attempt has been made to investigate the effect of Chlorpyrifos insecticide on carp Cyprinus carpio L. through acute toxicity bioassay. The LC50 were estimated as 1897, 1266, 985 and 792 μg/L during 24 , 48, 72 and 96 hr. respectively by using the concentrations 500 , 1000, 1500 , 2000, 2500 and 3000 μg/L indicating high sensitivity of fish to chlorpyrifos. The behavioral response observed in the fish were erratic swimming, loss of reflex, hyperactivities, decrease in appetite secretion of mucus, increase movement of operculum and hyperventilation . These effects increased with increasing concentration of the chlorpyrifos and duration of exposure.
Background: Analysis of human reports and comparison with results of experimental animals indicate that the effects of progesterone on human not analogous to experimental animals fetus, many studies showed that exposure to progesterone during developing of genital tract of human fetus was not teratogenic. Other studies which performed on laboratory animals found association between progesterone administration during gestation and genital malformation. Objectives: to explore the effect of progesterone in 10.2 mg/kg intraperitoneal injection in mice on testis development and anogenital distance. Materials and Methods: ten pregnant mice divided into five mouse control group that injected10. 2mg/kg sesame oil and treated group that injected pro
... Show MoreThe prediction of the blood flow through an axisymmetric arterial stenosis is one of the most important aspects to be considered during the Atherosclrosis. Since the blood is specified as a non-Newtonian flow, therefore the effect of fluid types and effect of rheological properties of non-Newtonian fluid on the degree of stenosis have been studied. The motion equations are written in vorticity-stream function formulation and solved numerically. A comparison is made between a Newtonian and non-Newtonian fluid for blood flow at different velocities, viscosity and Reynolds number were solved also. It is found that the properties of blood must be at a certain range to preventing atheroscirasis
This study involved the evaluation of Alcoholic extract of Nerium Oleander L. plant that have a promising anticancer cell. This extract was compared to the well known anticancer drug Cis – Platinum by utilizing an in vivo system in female Albino mice. The first direction was cytogenetically using the mitotic Index of bone marrow cells as a parameter for the cytotoxic effect of this extract. The second direction was enzymatical using a widely distributed enzyme GOT in the different organs of mice: Liver , kidney , spleen and lung . Animals were treated with three doses of Cis-platin , 50 , 200 and 350 Mg/mouse for three days . The same doses were used for the other extract . This study showed that the extract have a promising anticance
... Show MoreThis work describes the weathering effects (UV-Irradiation, and Rain) on the thermal conductivity of PS, PMMA, PS/PMMA blend for packaging application. The samples were prepared by cast method at different ratios (10, 30, 50, 70, and 90 %wt). It was seen that the thermal conductivity of PMMA (0.145 W/m.K), and for PS(0.095 W/m.K), which increases by PS ratio increase up to 50% PS/PMMA blend then decreased that was attributed to increase in miscibility of the blend involved. By UV-weathering, it was seen that thermal conductivity for PMMA increased with UV-weathering up to (30hr) then decreased, that was attributed to rigidity and defect formation, respectively. For 30%PS/PMMA, there results showed unsystematic decrease in thermal conduct
... Show MoreThe influence of bias current on the bandwidth of chaotic signals in semiconductor lasers by optical feedback has been studied experimentally and numerically. The measured data reveal that the bandwidth increase when the system becomes chaotic and this chaotic signal has a broadband spectrum so it can be used as a carrier for the quantum key. Mixing chaotic signal and quantum key make a very small change in chaotic bandwidth that does not affect the security of data transmitted.
Background: Periodontal diseases are one of the major dental pathologies that affect human populations worldwide at high prevalence rates The term periodontal disease usually refers only to plaque related inflammatory disease of the dental supporting tissues. Mouth rinses which act as an anti-plaque agents mostly used as adjuncts to oral hygiene. Aims of the study: To Estimate and compare the effects of Aloe vera relative to chlorhexidine on the clinical periodontal parameters (plaque index, gingival index, bleeding on probing). Material and method: A total of 44 subjects with plaque-induced gingivitis, baseline of data were collected for (PLI, GI, and BOP) and underwent oral hygiene instruction, scaling and polishing, then divided into:
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