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This study was conducted to evaluate biologic responses of autogenous bone (particulate marrow and cancellous bone; PMCB) and beta-tricalcium phosphate ceramics (TCPC) to orthodontic stimuli. Nine dogs served as the experimental animals; three dogs underwent orthodontic tooth movement after grafting, three dogs received PMCB grafting without tooth movement, and three dogs received TCPC grafting without tooth movement. Immediately after extraction of the upper second and/or third incisors, the maxillary alveolar bone was resected bilaterally. Autogenous PMCB obtained from the iliac bone and TCPC were transplanted into each bone defect. Experimental tooth movement was initiated 2 to 4 weeks after the grafting and continued for 9 to 15 weeks. Sectional archwires with open-coil springs were used for distal movement of the upper first incisors into the extraction sites. Oxytetracycline and calcein were employed as bone markers. Sections of grafted areas including the teeth were prepared for light and fluorescence microscopy. The results revealed that both autogenous bone and TCPC presented similar adaptive changes to the original alveolar bone without any external stimuli. TCPC exhibited more prominent biodegradative responses to orthodontic force in association with new cementum formation. Root resorption was also less in the TCPC area than in the PMCB region. It Is shown that TCPC is biodegradative In nature and adaptive for remodeling during orthodontic tooth movement. This finding indicates that TCPC may be a better biocompatible alternative to autogenous bone transplanted into bone defects subjected to orthodontic tooth movement.

PurposeThe purpose of this study is to examine the impact of ownership structure such as family, government, institutional, foreign and public on dividend payouts as a representative of dividend policy of nonfinancial firms in Bangladesh.Design/methodology/approachThis study employs a dynamic panel data model, namely, differenced generalized method of moments (GMM), which follows a two-step process. The study uses annual data of a sample of 159 nonfinancial firms of Dhaka Stock Exchange for the period 2008–2017, which constitutes a panel data of 1,590 firm-year observations.FindingsThis study’s findings reveal that family and public ownerships have a significant and positive effect on dividend payouts, while government and institutional ownerships have a significant but negative effect. This study additionally incorporates some very important controlled variables and finds that except for size, all the selected controlled variables, i.e. lagged-one of dividend payout, returns on assets, debts to assets, price-earnings (PE) ratio, age and financial crisis have a significant effect on the dividend payouts. However, the findings support several dividend-related theories or hypotheses, i.e. agency cost theory, dividend stability theory and reputation hypothesis.Research limitations/implicationsThis study could consider some other aspects of corporate governance, as well as other emerging markets and financial institutions to perceive whether the results differ. Also, investigation could be carried out on conventional and Islamic firms individually to observe if the findings are different. However, the researchers are suggested to incorporate these issues in their future studies.Practical implicationsThis study offers an important insight into the relationship dynamics between dividend payouts and ownership structure in the context of an emerging market like Bangladesh. Moreover, it enhances the understanding of the ties of dividend payouts with the firm-specific factors as well as the financial crisis. The findings of the present study have also important implications for managers, policymakers and researchers, who are in quest of directions on the dividend policy of publicly listed nonfinancial firms.Originality/valueMost of the previous studies consider one or two types of ownership to examine the impacts on dividend payouts, while this study uses five types of ownership accompanied by a different data set. Moreover, to the authors’ knowledge, no study in Bangladesh has yet addressed this issue in such a comprehensive manner as theirs.

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Unsteady MHD free convection and mass transfer flow through a vertical oscillatory porous plate with hall, ion-slip currents and heat source in a rotating system are studied. The governing equations of the problem contain a system of non-linear coupled partial differential equations. The coupled non-linear partial differential equations are solved by explicit finite difference method and the numerical results have been calculated by Compaq Visual 6.6a. For good accuracy, stability and convergence analysis have been analyzed. The results of this investigation are discussed for the different values of the well-known parameters and are shown graphically.