Aim To develop a low-density polyethylene–hydroxyapatite (HA-PE) composite with properties tailored to function as a potential root canal filling material. Methodology Hydroxyapatite and polyethylene mixed with strontium oxide as a radiopacifier were extruded from a single screw extruder fitted with an appropriate die to form fibres. The composition of the composite was optimized with clinical handling and placement in the canal being the prime consideration. The fibres were characterized using infrared spectroscopy (FTIR), and their thermal properties determined using differential scanning calorimetry (DSC). The tensile strength and elastic modulus of the composite fibres and gutta-percha were compared, dry and after 1 month storage in simulated body fluid (SBF), using a universal testing machine. The radiopacity of the fibres was determined using digital radiography. The interaction of the composites with eugenol was evaluated and compared with gutta-percha. Data of the tensile test were submitted to two-way anova and Bonferroni tests (P < 0.05). Results The endothermic peaks obtained from the DSC studies showed that the melting point of the HA/PE composites ranged between 110.5 and 111.2 °C, whereas gutta-percha exhibited a melting point at 52 °C. The tensile strength and elastic modulus of the silanated HA/PE composites were significantly higher than those of gutta-percha (P < 0.0001) under dry conditions and 1 month storage in SBF. The gutta-percha in eugenol showed a significant increase in the polymer molar mass, whereas the silanated HA/PE composites were unchanged. Radiological evaluations demonstrated that silanated HA/PE fibres were sufficiently radiopaque. Conclusion Promising materials for endodontic applications have been developed, offering relevant benefits over the traditional materials in terms of mechanical and chemical properties
Oxidative stress is oxidative damage caused by free radicals and reactive oxygen species (ROS). These ROS can cause oxidative damage to cellular components, including membrane lipids, receptors, enzymes, proteins, and nucleic acids. It would eventually lead to cell apoptosis and the appearance of certain pathological conditions. This work investigates the antioxidant potentials of chamomile extract in vitro by evaluating the extract activity to scavenge 2,2-Diphenyl-1-picrylhydrazyl (DPPH), also in vivo by investigating its effects on oxidative stress-induced rats by assessing the total oxidant status (TOS) and total antioxidant capacity in the radiation exposed rats with and without the treatment with chamomile extract. The results
... Show MoreBN Rashid, Nasaq, 2015
In the present paper, an eco-epidemiological model consisting of diseased prey consumed by a predator with fear cost, and hunting cooperation property is formulated and studied. It is assumed that the predator doesn’t distinguish between the healthy prey and sick prey and hence it consumed both. The solution’s properties such as existence, uniqueness, positivity, and bounded are discussed. The existence and stability conditions of all possible equilibrium points are studied. The persistence requirements of the proposed system are established. The bifurcation analysis near the non-hyperbolic equilibrium points is investigated. Numerically, some simulations are carried out to validate the main findings and obtain the critical values of th
... Show MoreThe production of polyhydroxyalkanoates PHAs from biopolymer degrading bacteria was examined
Wohlfahrtia longicorpuris sp. nov., from Iraq described, illustrated and distinguished from related species. The adults were reared from larvae collected from ulcer of a human face. Wohlfahrtia Brauer and Bergenstam is one of most important genus,which contains 19 species (Pape, 1998), some of these produce myiasis in mammals (Verves,1985).Taxonomic revision of this genus has been carried out by the following authors: Rohdendrof (1956), Zumpt (1965) and Pape (1996).
Abstract This study seeks to deal academically with how the EU treats clandestine immigration, through adopting a purley security approach, based on the European understanding of security threats posed to the security of communities and States in EU at all levels. So they agreed upon criminalizing this threat within the bloc while using repressive tools and steps to limit illegal immigrants flow to European territories. Accordingly, the EU gave the phenomen a security character. So it takes it from low politics level , that of employment and economic field to that of high politics, as a new security problem lying within a new security language embraced by ruling European elites, in other words EU touched on this issue as a speech act emp
... Show MoreThe present study aimed to determine the frequency of ABO and Rh blood group antigens among Sabians (Mandaeans) population. This paper document the frequency of ABO and Rh blood groups among the Sabians (Mandaeans) population of Iraq.There is no data available on the ABO/Rh (D) frequencies in the Sabians (Mandaeans) population. Total 341 samples analyzed; phenotype O blood type has the highest frequency 49.9%, followed by A 28.7%, and B 13.8% whereas the lowest prevalent blood group was AB 7.6%. The overall phenotypic frequencies of ABO blood groups were O>A>B>AB. The allelic frequencies of O, A, and B alleles were 0.687, 0.2 and 0.1122 respectively. Rhesus study showed that with a percentage of 96.2% Rh (D) positive is by far the mo
... Show MoreThe main aim of this study is to evaluate the remaining oil in previously produced zones, locate the water productive zone and look for any bypassed oil behind casing in not previously perforated intervals. Initial water saturation was calculated from digitized open hole logs using a cut-off value of 10% for irreducible water saturation. The integrated analysis of the thermal capture cross section, Sigma and Carbon/oxygen ratio was conducted and summarized under well shut-in and flowing conditions. The logging pass zone run through sandstone Zubair formation at north Rumaila oil field. The zones where both the Sigma and the C/O analysis show high remaining oil saturation similar to the open hole oil saturation, could be good oil zones that
... Show MoreBackground/Objectives: The purpose of current research aims to a modified image representation framework for Content-Based Image Retrieval (CBIR) through gray scale input image, Zernike Moments (ZMs) properties, Local Binary Pattern (LBP), Y Color Space, Slantlet Transform (SLT), and Discrete Wavelet Transform (DWT). Methods/Statistical analysis: This study surveyed and analysed three standard datasets WANG V1.0, WANG V2.0, and Caltech 101. The features an image of objects in this sets that belong to 101 classes-with approximately 40-800 images for every category. The suggested infrastructure within the study seeks to present a description and operationalization of the CBIR system through automated attribute extraction system premised on CN
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