The effects of corporate governance mechanisms on the financial leverage–profitability relation

Purpose This paper aims to investigate the moderating effects of corporate governance mechanisms on the financial leverage–profitability relation in emerging market firms. Design/methodology/approach The paper examines the impacts by estimating the empirical model in which a firm’s accounting profitability is a dependent variable, while financial leverage, board size, board independence, CEO duality, CEO ownership, state ownership and the interaction variables are predictors. The paper uses the panel data set of 295 listed firms in Vietnam in the period 2011-2015 and two key econometric methods for panel data, namely, the two-stage least square instrumental variable and general moments method. Findings The paper finds the evidence for the significant and positive effect of board size, board independence and state ownership on the financial leverage–profitability relation. The effect of CEO duality on the financial leverage–profitability relation tends to be negative, and the impact CEO ownership inclines to be positive, although both of them are statistically insignificant. The results are consistent across different estimation methods. Originality/value This paper is the first investigating the moderating effect of various corporate governance mechanisms on the financial leverage–profitability relationship in emerging market firms

Debt financing and firm performance: The moderating role of board independence

This article investigates the moderating role of board independence in the relationship between debt financing and performance of emerging market firms. We have used an empirical model in which the firm’s accounting profitability is a dependent variable and the independent variables are debt financing, board independence, the interaction variable made of debt financing and board independence as well as various control variables. Our analysis is based on a panel data set of 300 listed firms in Vietnam between 2013 and 2017. Our study finds that debt financing has a significantly negative effect and that board independence reduces the adverse impact of debt financing on accounting profitability. Our results are consistent across different estimation models and methods

Distinct distances on regular varieties over finite fields

In this paper we study some generalized versions of a recent result due to Covert, Koh, and Pi (2015). More precisely, we prove that if a subset $\mathcal{E}$ in a regular variety satisfies $|\mathcal{E}|\gg q^{\frac{d-1}{2}+\frac{1}{k-1}}$, then $\Delta_{k, F}(\mathcal{E})\supseteq \mathbb{F}_q\setminus \{0\}$ for some certain families of polynomials $F(\mathbf{x})\in \mathbb{F}_q[x_1, \ldots, x_d]$

Bringing Learning Back In: Examining Three Psychometric Models for Evaluating Learning Progression Theories

Learning progressions provide potentially valuable information to teachers about how to develop a scope and sequence for a group of learning objectives. However, for the learning progressions to be valuable, the progressions must be supported. Although there are several approaches and models that can be used to evaluate the validity of a learning progression, there is a dearth of research examining the advantages and limitations of each approach. The purpose of this study was to examine a multi-dimensional item response theory model and two cognitive diagnostic models (DINA and HO-DINA) for evaluating two learning progressions via a simulation study. In addition, the models were applied to empirical data to determine if the models provided consistent results. The results from the investigation indicated that five methods of using the model and statistical methods derived from them to testify learning level order could complement each other. None of the methods worked dominantly better than the others but they all deemed useful in certain contexts. With respect to assessing the possible links among levels across progressions, the degree to which the model recovered the true information in the simulation studies varied depending on the model and the magnitude of the difference between the learning levels. The more distant the levels were, the more accurate the model became at recovering the true classification. For the empirical analysis, three models provided convergent evidence to support almost all the aspects of the theory underlying two progressions considered in this study. Statistical results also suggested a few revisions to make the theory more in line with the empirical evidence. Four limitations were discussed, and six future directions were elaborated to address the drawbacks of this study. Finally, three practical implications were presented as take-away messages from this dissertation

Twist1 and Etv5 are part of a transcription factor network defining T helper cell identity

Indiana University-Purdue University Indianapolis (IUPUI)CD4 T helper cells control immunity to pathogens and the development of inflammatory disease by acquiring the ability to secrete effector cytokines. Cytokine responsiveness is a critical component of the ability of cells to respond to the extracellular milieu by activating Signal Transducer and Activator of Transcription factors that induce the expression of other transcription factors important for cytokine production. STAT4 is a critical regulator of Th1 differentiation and inflammatory disease that attenuates the gene-repressing activity of Dnmt3a. In the absence of STAT4, genetic loss of Dnmt3a results in de-repression of a subset of Th1 genes, and a partial increase in expression that is sufficient to observe a modest recovery of STAT4-dependent inflammatory disease. STAT4 also induces expression of the transcription factors Twist1 and Etv5. We demonstrate that Twist1 negatively regulates Th1 cell differentiation through several mechanisms including physical interaction with Runx3 and impairing STAT4 activation. Following induction by STAT3-activating cytokines including IL-6, Twist1 represses Th17 and Tfh differentiation by directly binding to, and suppressing expression of, the Il6ra locus, subsequently reducing STAT3 activation. In contrast, Etv5 contributes only modestly to Th1 development but promotes Th differentiation by directly activating cytokine production in Th9 and Th17 cells, and Bcl6 expression in Tfh cells. Thus, the transcription factors Twist1 and Etv5 provide unique regulation of T helper cell identity, ultimately impacting the development of cell-mediated and humoral immunity

Solid state synthesis of Polar Magnetic Oxides

Non-centrosymmetric polar oxides are subjects of considerable interest due to varieties of important phenomena and associated functional properties. Magnetoelectric multiferroic oxides are one such system where the magnetic properties can be controlled by electric field or the electric properties can be controlled by the magnetic field. This cross tunability magnetic and electrical properties makes multiferroic materials ideal candidates for making actuators, field sensors and memory devices. Simultaneous presence of broken inversion symmetry (electric polarization) and magnetism are two key requirements for multiferroicity. Non-centrosymmetric polar magnetic oxides simultaneously offer both (polarization and magnetization) properties. Therefore, we are working toward synthesis and investigation of non-centrosymmetric polar magnetic oxides of RMWO6 (R= Rare earth, M= Cr, Fe) family

Markov-functional and stochastic volatility modelling

In this thesis, we study two practical problems in applied mathematical fi nance. The first topic discusses the issue of pricing and hedging Bermudan swaptions within a one factor Markov-functional model. We focus on the implications for hedging of the choice of instantaneous volatility for the one-dimensional driving Markov process of the model. We find that there is a strong evidence in favour of what we term \parametrization by time" as opposed to \parametrization by expiry". We further propose a new parametrization by time for the driving process which takes as inputs into the model the market correlations of relevant swap rates. We show that the new driving process enables a very effective vega-delta hedge with a much more stable gamma profile for the hedging portfolio compared with the existing ones. The second part of the thesis mainly addresses the topic of pricing European options within the popular stochastic volatility SABR model and its extension with mean reversion. We investigate some effcient approximations for these models to be used in real time. We first derive a probabilistic approximation for three different versions of the SABR model: Normal, Log-Normal and a displaced diffusion version for the general constant elasticity of variance case. Specifically, we focus on capturing the terminal distribution of the underlying process (conditional on the terminal volatility) to arrive at the implied volatilities of the corresponding European options for all strikes and maturities. Our resulting method allows us to work with a variety of parameters which cover long dated options and highly stress market condition. This is a different feature from other current approaches which rely on the assumption of very small total volatility and usually fail for longer than 10 years maturity or large volatility of volatility. A similar study is done for the extension of the SABR model with mean reversion (SABR-MR). We first compare the SABR model with this extended model in terms of forward volatility to point out the fundamental difference in the dynamics of the two models. This is done through a numerical example of pricing forward start options. We then derive an effcient probabilistic approximation for the SABRMR model to price European options in a similar fashion to the one for the SABR model. The numerical results are shown to be still satisfactory for a wide range of market conditions

カシノナガキクイムシの飛翔と寄主選択に関する生態学的研究

京都大学0048新制・課程博士博士(農学)甲第22787号農博第2430号新制||農||1081(附属図書館)学位論文||R2||N5307(農学部図書室)京都大学大学院農学研究科森林科学専攻(主査)教授 井鷺 裕司, 教授 森 直樹, 准教授 大澤 直哉学位規則第4条第1項該当Doctor of Agricultural ScienceKyoto UniversityDFA