The dynamics of the volatility – trading volume relationship: New evidence from developed and emerging markets

This paper empirically investigates whether there is an evolution in the relation between stock market trading volume and volatility in 23 developed and 15 emerging markets. To answer this question, we develop a dynamic application of the TARCH (1, 1) model and first prove that the relationship is variable through time. Then, we focus our analysis on three major financial events, namely the Asian Crisis, the Dot Com bubble burst and the Subprime crisis. We find that the explanatory power of volume is greater during these periods. Finally, we show that the sign of the relationship cannot be clearly set for a specific country or sub group of developed or emerging markets.Mixture of distribution hypothesis, TARCH model, Conditional variance, Trading volume

UK-EU trade: the combination of Brexit, wider societal and industrial trends, and COVID-19 is creating a perfect storm for British exporting companies

The post-Brexit Trade and Cooperation Agreement (TCA) between the UK and the EU is nominally a free trade agreement for goods. Bob Hancké, Laurenz Mathei and Artus Galiay examine in more detail what the agreement does and does not mean for trade. They explain why it falls some way short of establishing ‘free trade’

Dancing in the dark: what Brexit means for UK-EU trade and UK industry

The post-Brexit Trade and Cooperation Agreement (TCA) between the UK and the EU is nominally a free trade agreement for goods. Bob Hancké, Laurenz Mathei and Artus Galiay examine in more detail what the agreement does and does not mean for trade. They argue the agreement falls some way short of establishing ‘free trade’ and that the combination of Brexit, wider secular societal and industrial trends, and the pandemic are creating a perfect storm for British exporting companies

Competencias lingüísticas y alumnado inmigrante en Cataluña. El caso del colectivo de origen hispanohablante

En la actualidad se constata una presencia elevada de alumnado de origen extranjero en los centros educativos del Estado español en general y en Cataluña en particular. En este contexto, el desarrollo de niveles de competencia lingüística suficientes para poder seguir la escolaridad sea uno de los elementos que genera una mayor preocupación en la escuela. En el caso de Cataluña, tiene especial relevancia al tratarse de un sistema educativo organizado bajo los parámetros de la educación bilingüe. Con este marco de fondo, se analiza la competencia lingüística en catalán y castellano de 262 alumnos inmigrantes, atendiendo específicamente al hecho de «ser o no ser hispanohablante». Los resultados fueron comparados con 341 alumnos autóctonos de Educación Secundaria Obligatoria. Los datos resultantes de testar dicha competencia, contrastada con los obtenidos por sus iguales autóctonos, muestran diferencias a favor de estos últimos realmente importantes

Testability enhancement of a basic set of CMOS cells

Testing should be evaluated as the ability of the test patterns to cover realistic faults, and high quality IC products demand high quality testing. We use a test strategy based on physical design for testability (to discover both open and short faults, which are difficult or even impossible to detect). Consequentially, layout level design for testability (LLDFT) rules have been developed, which prevent the faults, or at least reduce the chance of their appearing. The main purpose of this work is to apply a practical set of LLDFT rules to the library cells designed by the Centre Nacional de Microelectrònica (CNM) and obtain a highly testable cell library. The main results of the application of the LLDFT rules (area overheads and performance degradation) are summarized and the results are significant since IC design is highly repetitive; a small effort to improve cell layout can bring about great improvement in design

Using Sensitivity Analysis to Develop a Validated Computational Model of Post-operative Calvarial Growth in Sagittal Craniosynostosis

Craniosynostosis is the premature fusion of one or more sutures across the calvaria, resulting in morphological and health complications that require invasive corrective surgery. Finite element (FE) method is a powerful tool that can aid with preoperative planning and post-operative predictions of craniosynostosis outcomes. However, input factors can influence the prediction of skull growth and the pressure on the growing brain using this approach. Therefore, the aim of this study was to carry out a series of sensitivity studies to understand the effect of various input parameters on predicting the skull morphology of a sagittal synostosis patient post-operatively. Preoperative CT images of a 4-month old patient were used to develop a 3D model of the skull, in which calvarial bones, sutures, cerebrospinal fluid (CSF), and brain were segmented. Calvarial reconstructive surgery was virtually modeled and two intracranial content scenarios labeled “CSF present” and “CSF absent,” were then developed. FE method was used to predict the calvarial morphology up to 76 months of age with intracranial volume-bone contact parameters being established across the models. Sensitivity tests with regards to the choice of material properties, methods of simulating bone formation and the rate of bone formation across the sutures were undertaken. Results were compared to the in vivo data from the same patient. Sensitivity tests to the choice of various material properties highlighted that the defined elastic modulus for the craniotomies appears to have the greatest influence on the predicted overall skull morphology. The bone formation modeling approach across the sutures/craniotomies had a considerable impact on the level of contact pressure across the brain with minimum impact on the overall predicated morphology of the skull. Including the effect of CSF (based on the approach adopted here) displayed only a slight reduction in brain pressure outcomes. The sensitivity tests performed in this study set the foundation for future comparative studies using FE method to compare outcomes of different reconstruction techniques for the management of craniosynostosis