Push-out bond strength of different root canal obturation systems to root canal dentin

AbstractAimTo evaluate and compare push-out bond strength of four obturation systems; Gutta-percha/AH Plus, GuttaFlow, RealSeal and EndoREZ system to root canal dentin.Materials and methodsHuman freshly extracted 80 mandibular premolars were prepared and assigned to experimental groups (n = 20), designated as Group I: Gutta-percha/AH Plus, Group II: GuttaFlow system, Group III: RealSeal points/RealSeal Self-etch and EndoREZ obturation system. After obturation, each tooth was prepared for push-out assessment with root slices of 2 mm thickness using universal testing machine. Data were analyzed using one way ANOVA in a level of confident at 95%.ResultsGutta-percha/AH Plus root fillings showed significantly highest bond strength. Whereas root segment location did not have a significant influence on bond strength except with Group III.ConclusionThe adhesiveness quality to root dentin promoted by newer methacrylate resin-based obturation systems like RealSeal and EndoREZ systems is compromised even when teeth with simple anatomic features were obturated under well-monitored laboratory conditions

Towards the Development of an Empirical Model for Islamic Corporate Social Responsibility: Evidence from the Middle East

Academic research suggests that variances in contextual dynamics, and more specifically religion, may lead to disparate perceptions and practices of corporate social responsibility (CSR). Driven by the increased geopolitical and economic importance of the Middle East and identified gaps in knowledge, the study aims to examine if indeed there is a divergent form of CSR exercised in the region. The study identifies unique CSR dimensions and constructs presented through an empirical framework in order to outline the practice and perception of CSR in a context with strong Islamic beliefs. The framework goes beyond the platform of mere Islamic philanthropy and is based on CSR-stakeholder management practices. Following an exploratory research design and collecting interview data from representatives of 63 organisations from Saudi Arabia, the United Arab Emirates and Oman, the study offers a snapshot of the CSR reality from the perspective of those living the phenomenon. The results suggest that the practice and perception of CSR in the examined context are largely grounded in the areas of social and altruistic actions but they cannot be examined in isolation from the religious context of CSR operation. This focus is mainly attributed to the dominant role of Islam in the examined sample, which leads to forms of non-structured or semi-structured approaches to CSR. Apart from the theoretical advancements offered to the CSR literature, the study also provides contributions for practitioners and policy makers.</p

Capacity of driven piles in cohesionless soils including residual stresses

Static formulas based on limit equilibrium theories often provide misleading predictions of pile capacity in cohesionless soils. Researchers have been working within the last few years to improve empirical prediction methods. However, even the most recent methods neglect one or more of four factors; namely: residual stresses due to pile driving, actual soil parameters prior to failure, mean normal stress levels, and stress history. Available indirect methods used for residual stress measurement are not accurate. Furthermore, no accurate method for their prediction, except the wave equation, is available. Therefore, in this dissertation a new method that takes into account all related parameters for residual stress prediction was developed. It was shown that the existence of these stresses is the principal reason for observing limit values of pile tip and shaft capacities. Due to high stress levels beneath the pile tip prior to failure, the initial angle of shearing resistance may be substantially reduced. This may result in serious overestimation of the pile tip capacity, especially in dense sands, if the initial angle were used. In this research, a procedure was developed to account for this behavior. For many of the available methods, the vertical overburden pressure was used for predicting pile capacity. However, this capacity is actually affected by the mean normal stress. Correlations in terms of this stress are proven to be superior to those produced when the overburden pressure was used. Stress history was found to have a major effect on pile capacity in both reducing soil compressibility and increasing lateral pressure on the pile shaft, and hence increasing the pile capacity. These effects have not been taken into account in available prediction methods. In this research, available load test data were properly adjusted for residual stresses, and were then used to develop a new empirical prediction method for driven piles in cohesionless soils. The new method takes into account parameters at failure, mean normal stress, and stress history. This method was indicated to be superior to other available methods by comparison with actual measurements

Women Against Society: Madame Bovary and The Awakening in the Nineteenth Century

[abstract not available

Secondary Metabolites in Basil, Bio-Insecticide, Inhibition Effect, and In Silico Molecular Docking against Proteolytic Enzymes of the Red Palm Weevil (Rhynchophorus ferrugineus)

The purpose of this work was to determine the secondary metabolites generated by O. basilicum cell suspensions, as well as their insecticide and inhibitory activity against R. ferrugineus. The growth kinetics with inoculation Verticillium dahliae were determined and identified using LC-MS. Determination of total phenolic components (TFC), flavonoids (TF), and condensed tannins (TCT) were measured. Insecticidal activity of O. basilicum extract against R. ferrugineus (larva and adult) and proteolytic enzymes activity were assessed (in vitro and in vivo). The O.basilicum extract had an LC50 of 1238 &micro;g/mL and an LD50 of 13.4 &micro;g/larva. The LC50 of chicoric acid, ursolic acid, salvigenin, quercetin-3-O-rutinoside, rosmarinyl glucoside, and nepetoidin B demonstrated activity at an LC50 of 1132, 1167, 1189, 1214, 1275, and 1317 &micro;g/mL, respectively. Chicoric acid, salvigenin, nepetoidin B, and rosmarinic acid demonstrated an LD50 activity of 10.23, 11.4, 11.9, and 12.4 &micro;g/larva, respectively. The active extract of O. basilicum inhibited total protease, trypsin-like serine proteinases, elastase, cysteine, and metalloprotease activity with an IC50 (in vitro) of 119.4, 91, 102.4, 76.4, and 52.4 &micro;g/mL, respectively. In silico studies of compounds were conducted, such as molecular docking and ADMET analysis. The study proposes using an efficient cell suspension technique to produce O. basilicum extract containing active secondary metabolites and accessible using as bio-insecticide

Inclusion Relations between α-Modulation Spaces and Triebel–Lizorkin Spaces

In this paper, we obtain conditions of the inclusion relations between α-modulation spaces and Triebel–Lizorkin spaces