Lively children trapped in an island of disadvantage: Verbal play of Cantonese working-class schoolboys in Hong Kong

In this paper I describe the mocking and playful verbal practices of some Cantonese working-class secondary schoolboys in an English language lesson in Hong Kong. I show how these Cantonese-speaking adolescents seek to assert their indigenous identity and their ingenious Cantonese competence in an educational system that places Cantonese at the bottom of the hierarchy of languages. These self-asserting verbal practices of working- class schoolboys, while in themselves artful and playful, do not contribute to the breaking through of the reproduction and perpetuation of these schoolboys' subordinated and insulated Cantonese sociocultural world, where there is little access to the socioeconomically dominant symbolic resource of English. Without access to English, they can hardly access the middle-class bilingual identity and the socioeconomic success and social status that come with it. Paradoxically, by acting out resistance to an alienating English curriculum, they contribute to the perpetuation of their own insularity and subordination and are trapped in a cycle of disadvantage. The paper concludes with a discussion of the possible impact of the transition of Hong Kong from a British colony to a Special Administrative Region (SAR) of China on language, identity, and social class in post-1997 Hong Kong. © Walter de Gruyter.postprin

The Rise and Fall of S&P500 Variance Futures

Volatility is an indispensible component of sensible portfolio risk management. The volatility of an asset of composite index can be traded by using volatility derivatives, such as volatility and variance swaps, options and futures. The most popular volatility index is VIX, which is a key measure of market expectations of volatility, and hence is a key barometer of investor sentiment and market volatility. Investors interpret the VIX cash index as a “fear” index, and of VIX options and VIX futures as derivatives of the “fear” index. VIX is based on S&P500 call and put options over a wide range of strike prices, and hence is not model based. Speculators can trade on volatility risk with VIX derivatives, with views on whether volatility will increase or decrease in the future, while hedgers can use volatility derivatives to avoid exposure to volatility risk. VIX and its options and futures derivatives has been widely analysed in recent years. An alternative volatility derivative to VIX is the S&P500 variance futures, which is an expectation of the variance of the S&P500 cash index. Variance futures are futures contracts written on realized variance, or standardized variance swaps. The S&P500 variance futures are not model based, so the assumptions underlying the index do not seem to have been clearly understood. As these two variance futures are thinly traded, their returns are not easy to model accurately using a variety of risk models. This paper analyses the S&P500 3-month variance futures before, during and after the GFC, as well as for the full data period, for each of three alternative conditional volatility models and three densities, in order to determine whether exposure to risk can be incorporated into a financial portfolio without taking positions on the S&P500 index itself.Risk management, financial derivatives, futures, options, swaps, 3-month variance futures, 12-month variance futures, risk exposure, volatility.

A Nexus of Supportive Infrastructure to Foster Student Learning, Engagement, & Flourishing During the COVID-19 Pandemic

In 2020, educators and students were faced with a global pandemic that created unprecedented challenges to classrooms across the nation. For many students, the shift to online learning in a necessary effort to maintain educational continuity lasted for an entire academic year. Students attended online synchronous and asynchronous class sessions, interacted with their peers in exclusively online settings, and were isolated to the social and economic constraints of their own households. This study examines the dramatic impact that these virtual learning experiences had on middle school students’ learning, engagement, and development during the COVID-19 pandemic. By interviewing middle school students, teachers, and parents of students who participated in remote learning, researchers identified the necessity of a nexus of interconnected support founded on the relationships between the students, parents, and teachers both inside and outside of educational contexts to foster student engagement. This nexus of support was even more imperative for the success of low-income students and students who were children from immigrant families. Even when all conditions of this nexus were met, however, it was still necessary for students to display a remarkable level of intrinsic motivation and self-help behavior in order to maintain consistent engagement. These findings suggest the a radical reimagination of the educational landscape for students and educators’ return to the physical classroom: (1) the prioritization of a dynamic, personalized, and evolving curriculum, (2) community-focused, inquiry-based pedagogy, and (3) an audit system that ensures students are consistently supported in all three conditions of the support nexus

Suppression of parasitic resonance in piezoresistively transduced longitudinal mode MEMS resonators

This paper demonstrates the suppression of parasitic resonance in a piezoresistively transduced longitudinal mode MEMS resonator, wherein beams are electrostatically excited in a combined extensional mode with an associated frequency-Q product of 3.28 Ã? 1012. The response of the beam is sensed using both capacitive and piezoresistive transduction principles. The resonator consists of six parallel beams linked to a central anchor and a pair of symmetrical parallel beams that force the beams to vibrate in-phase. The mode suppression in the resonator is compared with other structures by finite element analysis (FEA). The relative distribution of strain energies in both the resonant structure and anchors and in both primary and secondary directions of vibration are proposed as figures of merit to compare this device to previously reported longitudinal mode beam resonators. The design optimization of longitudinal mode beam resonators is also discussed

Dynamic response of water droplet coated silicon MEMS resonators

This paper studies the dynamic response of silicon bulk acoustic mode resonators spotted with water droplets of varying volume on the top surface. Three different cases were compared: (i) bare silicon resonators, (ii) parylene C coated resonators and (iii) hydrophobic self assembled monolayer coated resonators. Experimentally derived variations in quality factor are compared with those obtained analytically for the electrostatically driven square extensional mode resonator. The measured quality factors showed a good agreement with the models

Electrostatically transduced face-shear mode silicon MEMS microresonator

Silicon microresonators are increasingly viewed as attractive candidates for a variety of frequency selective signal processing applications due to miniaturization and potential for integration with CMOS. In this work, we present a new electrostatically transduced face-shear (FS) mode square plate single crystal silicon resonator that rivals previously reported bulk mode resonator topologies and demonstrates good frequency scaling. A microfabricated face-shear mode resonator with 800 ?m side length demonstrates a resonant frequency of 3.638 MHz, Q of 11193 in air and 836283 in vacuum as well as a TCF of -19ppm/K

Mechanically coupled bulk-mode dual resonator mass sensor

AbstractThe adaptation of micro- and nanomechanical resonators as mass balances for biochemical sensing has received much attention in recent years due to the potential for very high resolution and electrical readout of target analyte in a label-free format. However, several implementation challenges arise from the necessity of operation in compatible biological buffer solutions. These challenges include minimizing undesired effects of fluid-structure interaction and buffer interference with signal transduction. Electrical readout of the sensor response is complicated by coupling to the electrical properties of the buffer solution and voltage limitations due to the possibility of undesired electrochemical reactions on the sensor surface. To address this problem we propose a novel dual resonator platform, wherein electrical transduction and sensing are spatially separated onto two different mechanically coupled resonators. In this work, we demonstrate the functionality of the dual resonator system as a mass sensing platform, with a mass responsivity of 37 Hz/ng