the effect of electrical currents by different modalities on wound healing has been experimented. in this study a survey of the literature shows different results, and the mechanisms of action have not been elucidated for certain. the aim of this study was to compare the results obtained from low voltage-square wave stimulation of different frequencies. results show that the healing period for ...

statement of problem: the bond strength of root canal sealers to gutta-percha seems to be an important property for maintaining the integrity of the apical seal which can result in reducing apical microleakage. purpose: the purpose of the present study was to compare the tensile bond strengths of four types of root canal sealers to gutta–percha. this study measured the maximum forces needed to ...

We constructed an atomic structure model for a PANbased carbon fiber containing amorphous structures using molecular dynamics methods. It was found that basic physical properties such as crystallinity, Young’s modulus, and thermal conductivity of our model were nearly identical to those of real carbon fibers. We then obtained the tensile strength of a carbon fiber, which has no macro defects. W...

In this paper we give an account of applications of quantum-mechanical (first-principles) electronic structure calculations to the problem of theoretical tensile strength in metals and intermetallics. First, we review previous as well as ongoing research on this subject. We then describe briefly the electronic structure calculational methods and simulation of the tensile test. This approach is ...

The aim of the present study is to investigate the effect of variation of polypropylene fibres ranging from 0.1% to 0.4% along with 0.8% steel fibres on the behaviour of fibrous concrete. The mechanical properties of the concrete such as compressive and tensile strength have been investigated. The result shows that addition of polypropylene fibre has a little effect on the compressive strength,...

PURPOSES To assess the tensile strength of the modified 4-strand cruciate technique for obliquely lacerated tendons, and to compare the findings with the strength of transversely lacerated tendons repaired at various grasping depths. METHODS 60 porcine front foot tendons were evenly divided into 4 groups. In groups 1 to 3, tendons were transversely lacerated and repaired with grasping points ...

this research paper presents the use of wasteful supplementary cementitious materials like fly ash and silica fume to conserve the cement used in concrete. the cement industry is one of the major producers of greenhouse gases and an energy user. in this study, portland cement was used as a basic cementitious material. fly ash and silica fume were used as the cement replacements by weight. the r...

in this research, the possibility of using high percentage of lignocellulosic fibers in making natural fiber-thermoplastic composite was studied. three weight percentages of bagasse flour namely 40, 55 and 70 percents were chosen. mapp was used as coupling agent at two weight percentages of pp, namely 0, 4 and 6 percents. tensile strength was measured applying instron 6025. the results showed t...

Various studies have reported a significant reduction in tensile bond strength of brackets when bonding is carried out immediately after bleaching. The purpose of this investigation was to determine the effect of an antioxidant agent on the tensile bond strength values of metal brackets bonded with composite resin to human enamel after bleaching with carbamide peroxide (CP). A total of 80 extra...