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With the growing use of headed bars in the RC beam-column joints to reduce reinforcement congestion in the joint region, more tests are needed to gain further insight into the behavior of these joints and perfect the related design codes. Given the limitations imposed in ACI318-14 on the type of concrete and the relative head area, which is the net bearing area of the head divided by the bar area, this study investigated the effect of these parameters by testing four interstory exterior joint specimens constructed at the 2 3 scale under cyclic loading. These tests investigated the compliance of the joints with the seismic criteria when: (1) the joint was made with the self-consolidating concrete instead of the normal one, and (2) the joint was designed with the relative head area set to 3 instead of 4. The results showed that the use of the self-consolidating concrete improved the seismic behavior of the joint and reducing the relative head area to 3 did not render the joint performance unacceptable. [ABSTRACT FROM AUTHOR]

Background: The aim of the present study was to investigate the impact of metal artifact reduction (MAR) algorithm of cone-beam computed tomography (CBCT) on the diagnostic accuracy of fenestration and dehiscence around dental implants.Methods: Twenty-three dental implants were placed adjacent to the dehiscence and 23 adjacent to the fenestration defects on bovine bone blocks. The blocks were scanned with CBCT unit in two modes, with and without MAR algorithm. The area under the receiver operator characteristic (ROC) curves (Az value), specificity, sensitivity, positive predictive value, negative predictive value, and accuracy were determined for all modes.Results: For both defects, the Az values were higher in off MAR condition. The values of sensitivity, positive predictive value, negative predictive value, and accuracy, were higher in off MAR condition for both defects. However, the specificity in both defects in the two modes was equal.Conclusion: The MAR algorithm in CBCT unit may not be helpful in increasing the diagnostic accuracy of fenestration and dehiscence around dental implants. [ABSTRACT FROM AUTHOR]

Shear walls are one of the important structural elements for bearing loads imposed on buildings due to winds and earthquakes. Composite shear walls with high lateral resistance, and high energy dissipation capacity are considered as a lateral load system in such buildings. In this paper, a composite shear wall consisting of steel faceplates, infill concrete and tie bars which tied steel faceplates together, and concrete filled steel tubular (CFST) as boundary columns, was modeled numerically. Test results were compared with the existing experimental results in order to validate the proposed numerical model. Then, the effects of some parameters on the behavior of the composite shear wall were studied; so, the diameter and spacing of tie bars, thickness and compressive strength of infill concrete, thickness of steel faceplates, and the effect of strengthening the bottom region of the wall were considered. The seismic behavior of the modeled composite shear wall was evaluated in terms of stiffness, ductility, lateral strength, and energy dissipation capacity. The results of the study showed that the diameter of tie bars had a trivial effect on the performance of the composite shear wall, but increasing the tie bars spacing decreased ductility. Studying the effect of infill concrete thickness, concrete compressive strength, and thickness of steel faceplates also showed that the main role of infill concrete was to prevent buckling of steel faceplates. Also, by strengthening the bottom region of the wall, as long as the strengthened part did not provide a support performance for the upper part, the behavior of the composite shear wall was improved; otherwise, ductility of the wall could be reduced severely. [ABSTRACT FROM AUTHOR]

Concrete shear walls are one of the major structural lateral resisting systems in buildings. In some cases, due to the change in the occupancy of the structure or functional requirements like architectural and even mechanical ones, openings need to be provided and installed in structural walls after their construction. Providing these openings may significantly influence the structural behavior of the constructed wall. This paper considers the results of a nonlinear finite element analysis of shear walls with opening strengthened by carbon fiber reinforced polymer (CFRP) strips with different configurations. Details of bond-slip constitutive model of link elements to simulate the connections of FRP strips to concrete surface is presented. The proposed model in this research has been validated using experimental results available in the literature. The results indicated that the proposed configuration of CFRP strips significantly improved the lateral resistance and deformation capacity of the shear walls with opening. [ABSTRACT FROM AUTHOR]

Background and Aim: Probiotics could have benefits on oral health, partially through modifying oral cavity microflora. The purpose of this study was to investigate the effect of a commercial probiotic yogurt consumption on oral halitosis. Materials and Methods: This clinical trial was conducted on 44 volunteers suffering from halitosis with oral cavity origin. The subjects were given 200 ml probiotic yogurt daily for a period of two weeks. One examiner evaluated subjects’ mouth odor at baseline and after two weeks using organoleptic assessment (5 point scale: 0= no, 1= brief, 2= medium, 3=severe, and 4= very severe) at 10 and 50 cm distances. Data were analyzed by SPSS software using Wilcoxon test (α=0.05). Result: Baseline mean organoleptic scores (10 and 50 cm) were 2.63±1.12 and 1.95±1.23, which decreased to 1.45±1.10 and 0.95±0.93 at the end of study (P< 0.001). Conclusion: consumption of probiotic products could be considered as an effective strategy for improvement of halitosis with mouth origin. [ABSTRACT FROM AUTHOR]