Dynamics of the dispersion interaction in an energy transfer system

On the propagation of resonant radiation through an optically dense system, photon capture is commonly followed by one or more near-field transfers of the resulting optical excitation. The process invokes secondary changes to the local electronic environment, shifting the electromagnetic interactions between participant chromophores and producing modified intermolecular forces. From the theory it emerges that energy transfer, when it occurs between chromophores with electronically dissimilar properties, can itself generate significant changes in the intermolecular potentials. This report highlights specific effects that can be anticipated when laser light propagates across an interface between differentially absorbing components in a model energy transfer system

Reducing Geo-risks for Offshore Developments

Risk and Reliability in Geotechnical Engineerin

The Extent of Segmental Reporting and its Value Relevance:Cross-Country Evidence

Purpose: The purpose of this paper is to examine the extent of segmental reporting disclosure and its value relevance to a sample of Qatari and Jordanian listed companies following the implementation review of the International Financial Reporting Standard (IFRS) 8. This was the first standard to be subjected to a post-implementation review. Annual reports are initially analyzed to investigate the level of segmental information that was published by companies in these two countries. Design/methodology/approach: Using the Ohlson (1995) model, the study employs regression analysis to test the hypotheses relating to the value relevance of the segmental disclosures uncovered. In addition, one-way ANOVA and Kruskal-Wallis tests are used to investigate any variation in segmental reporting among sectors. Findings: The findings indicate that the amount of segmental information disclosed by the sample firms differs across sectors. Moreover, the segmental information provided (including the number of segments and the amounts of disclosure) is value relevant and can explain the variations in firms share prices. Practical implications: The results of the current investigation have implications for policy makers, including the International Accounting Standards Board, as well as for accounting regulators in Jordan and Qatar. They suggest that the segmental disclosures supplied under IFRS 8 are value relevant for equity prices in a developing country context. Compliance with IFRS 8 should thus be monitored to ensure that all firms provide the segmental disclosures that they are meant to supply under the terms of the standard. Originality/value: This paper is one of the few to provide empirical evidence on the role of segmental reporting following the post-implementation review that was conducted for IFRS 8. 2018, Emerald Publishing Limited

The Impact of the COVID 19 Pandemic on Stock Market Volatility: Evidence from a Selection of Developed and Emerging Stock Markets

This study examines the impact of the COVID 19 pandemic on the stock markets of China, India, Pakistan, the UK and the US using Generalised Autoregressive Conditional Heteroscedasticity (GARCH) and Threshold GARCH models with COVID 19 as an exogenous dummy variable in the variance equation. The sample period of 2016 – 2021 is divided into two sub-periods: the pre-COVID 19 period and the COVID 19 period. The results of the study indicate that the COVID 19 pandemic had a significant impact on the stock market volatility of the sample markets. Results from both the GARCH and Threshold GARCH models further confirm that there was persistent volatility in these markets and that this volatility increased as a result of the pandemic. In addition, the Threshold GARCH results indicate that the asymmetric term was significant in all markets indicating that bad news, such as the pandemic, had a stronger impact on the conditional variance of the returns as compared to good news. In addition, the results further confirm that the US market had no significant impact on the volatility of the Chinese market during the pandemic. The results have important implications for (i) international investors regarding portfolio management and investment risk minimisation in situations like the COVID 19 pandemic; and (ii) policymakers in terms of how they respond to any future pandemic

The Impact of the COVID 19 Pandemic on Stock Market Volatility: Evidence from a Selection of Developed and Emerging Stock Markets

This study examines the impact of the COVID 19 pandemic on the stock markets of China, India, Pakistan, the UK and the US using Generalised Autoregressive Conditional Heteroscedasticity (GARCH) and Threshold GARCH models with COVID 19 as an exogenous dummy variable in the variance equation. The sample period of 2016 – 2021 is divided into two sub-periods: the pre-COVID 19 period and the COVID 19 period. The results of the study indicate that the COVID 19 pandemic had a significant impact on the stock market volatility of the sample markets. Results from both the GARCH and Threshold GARCH models further confirm that there was persistent volatility in these markets and that this volatility increased as a result of the pandemic. In addition, the Threshold GARCH results indicate that the asymmetric term was significant in all markets indicating that bad news, such as the pandemic, had a stronger impact on the conditional variance of the returns as compared to good news. In addition, the results further confirm that the US market had no significant impact on the volatility of the Chinese market during the pandemic. The results have important implications for (i) international investors regarding portfolio management and investment risk minimisation in situations like the COVID 19 pandemic; and (ii) policymakers in terms of how they respond to any future pandemic

An Investigation of the Weak Form of the Efficient Markets Hypothesis for the Kuwait Stock Exchange

This article investigates the weak form of the efficient market hypothesis (EMH) for the Kuwait Stock Exchange (KSE). In particular, it tests whether share returns on the KSE exhibit patterns which may be used to predict future share price changes. Ten filter rules are tested on weekly data for 42 firms over the period 1998–2011. The results suggest that the KSE was not weak-form efficient because patterns and trends were present in security prices. In addition, the results are consistent with the substantive literature which has argued that emerging stock markets are informationally inefficient, such as Fifield, Power and Sinclair (2005, 2008) and Xu (2010) and particularly those early studies of Al-Shamali (1989) and Al-Loughani and Moosa (1999) that looked at trading rules for the KSE. </jats:p

The effects of nonvascularized versus vascularized bone grafting on calvarial defect healing.

It remains unknown whether bone graft vascularity influences calvarial healing. The purposes of this study were (1) to develop a model to study nonvascularized and vascularized calvarial grafts as well as (2) to compare effects of bone graft vascularity on calvarial healing. Bilateral calvarial defects were created in 26 Wistar rats. The defects were left empty within 1 parietal region. On the contralateral side, the defects were partially closed with native parietal bone (control group, n = 6), nonvascularized (N-V, n = 10), or vascularized bone grafts (VAS, n = 10). The vascularized grafts were supplied by perforating dural arterioles. Bone mineralization and healing patterns from serial microcomputed tomographic scans were compared within and across the groups using parametric and nonparametric tests. Differences in bone mineral content across sides were significant between the groups at weeks 6 (P = 0.016) and 12 (P = 0.025). Bone formation was greater within both the control and VAS groups versus the N-V group at weeks 6 and 12 (P \u3c 0.05). Healing patterns differed between the groups (P \u3c 0.05), progressing through islands of new bone formation within the control and VAS groups while limited to defect margins on the N-V graft side. In conclusion, a bilateral calvarial defect model was established to study bone graft vascularity. Bone quantity and healing patterns differed in the presence of the nonvascularized versus vascularized grafts. Although the calvarial defect model is often applied within the plastic surgery literature to study bone substitutes, greater understanding of basic mechanisms influencing calvarial healing is first needed to avoid confounding results