Market volatility and spillover across 24 sectors in Vietnam

While market volatility and volatility connectedness across different financial markets have been examined, the spillover effects across sectors have been under-examined. As such, this study aims to examine market volatility and the volatility patterns for 24 Vietnamese sectors. Our study uses the ARMA-GARCH estimation technique over the 2012-2021 period. The spillover effects between these sectors are then investigated using the vector autoregression (VAR) technique. Three key findings are as follows. First, the market volatility of Development Investment, Education, and Securities is most affected by the market volatility from the previous periods, whereas Construction is least affected. Second, the Vietnamese stock market exhibits a substantial intersector connectedness above 60 per cent from 2012 to 2021. However, the sectoral spillover effects increase to around 90 per cent during the Covid-19 pandemic. We found that Aquaculture, Building Materials, Food, and Plastic are the four primary risk transmitters at the sectoral level. Third, market volatility for Energy, Plastic, and Steel is unaffected by the pandemic. Meanwhile, Securities, Fertilizer, and Transportation exhibited a significant increase in market volatility during Covid-19. Based on these empirical results, policy implications have emerged for the Vietnamese government to support affected industries to recover and develop.

An Analysis of the Impacts of Social Media on COVID-19 Vaccine Hesitancy in the U.S

The COVID-19 pandemic remains a public health emergency, although effective vaccines are available. Unfortunately, vaccine hesitancy (VH) has mitigated the effectiveness of vaccination campaigns. Preferred approaches to estimate VH are surveys, polls, and questionnaires;however, these methods are limited in scope because they capture VH at a single point in time and mostly in highly populated (urban) areas. A dearth of published research points to a knowledge gap that limits the ability to explain changes in VH over time at the county level. The proposed research uses open-access databases and data-driven approaches to fill this knowledge gap. We present a systematic, data-driven framework that analyzes sentiments on social media and news coverage on COVID-19 to estimate VH changes over time at the county level in the U.S. Understanding how sentiments and topics contribute to VH can help public health officials develop tailored strategies to increase vaccine uptake for different counties of the U.S., especially when data is limited. Our study indicates that the use of social media and online news coverage led to more reliable predictions of VH estimates for urban than rural areas. Future research will consider other factors which impact VH, such as social/demographic factors, weather conditions, vaccine mandates, etc. © 2022 IISE Annual Conference and Expo 2022. All rights reserved.

A Case Study on Humanoid Robot Using Robotics Software in E-learning

Due to the COVID-19 pandemic, E-learning is developed significantly to unlock the key factors that support researchers/students. This paper presents a software solution on an E-learning system to control the humanoid robot, which is essential for students’ knowledge and experimental studies in the academic environment. In particular, the research concentrates on controlling NAO robots in the virtual space. First, by installing Choregraphe software, the programs are developed to calibrate and handle different factors that contribute to the robot's performance, such as joint motions, collision avoidance, navigation, localization. After that, the detailed characteristics of the NAO robot are designed and displayed on the Webot 8.4 monitor. By transmitting the connection signal from the Choregraphe to Webot 8.4, the virtual environment analyzes the effectiveness and competencies of the controllers perceived by users. A case study is investigated to inspect the robot operation and the stability of the software solution. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

COVID-19 Case and Contact Investigation in an Office Workspace

This investigation report describes a case of COVID-19 in a combined military and civilian office workspace and the contact investigation and mitigation efforts that followed. This office space included an embedded public health officer who was able to conduct the contact investigation and advise on the outbreak response. Over a 3-day period, the index case unintentionally exposed 150 coworkers to SARS-CoV-2 through participation in carpools, conferences, and small meetings. Of these exposures 37 were considered medium risk at the time and 113 were considered low risk. A total of 5 contacts reported COVID-like-symptoms at the time of the investigation and another 5 developed symptoms during the14-day quarantine period and all were directed to self-isolate. None of the contacts required hospitalization and all the symptomatic contacts tested negative for SARS-CoV-2. With the advice and aid of the embedded public health officer, the office authorized telework, conducted thorough cleaning of spaces, distributed informative messaging, conducted virtual question-and-answer forums, and evaluated outbreak policies. This report demonstrates that the close integration of public health and office management can lead to rapid identification of those at risk of infection and implementation of mitigation and control efforts to stop the spread of disease.

Heritage conservation and tourism: the present and future of the past

This chapter examines the symbiosis of heritage conservation and tourism development at a UNESCO (United Nations Educational, Scientific and Cultural Organization) cultural heritage site, one of the most popular touristic sites in Vietnam. Bui, Le and Jones present findings derived from a longitudinal study over 5 years spanning before and during the COVID-19 pandemic (from 2016 to 2020). Although Hoi An has dramatically benefited from mass tourism, the excessive increase in visitor numbers and concentration in the core heritage zone of the city has negatively impacted the economic wealth of the residents of the ancient town. COVID-19 halted the development of tourism, which attracts attention to the overdependence of the city on tourism, and offers an opportunity for administrators to rethink and revise Hoi An's existing tourism policies.

Decomposition mechanism of hydroxychloroquine in aqueous solution by gamma irradiation.

One of the advanced oxidative processes is gamma irradiation, an efficient technique for removing pesticides and pharmaceutical products. Radiolytic degradation leads to free radical's formation, which facilitates molecular lesion and breaks the chemical bonds. The use of pharmaceutical compounds, such as hydroxychloroquine (HCQ), is increasing nowadays due to the Covid 19 pandemic situation. This study focused on gamma radiation-induced degradation of HCQ in aqueous solution. The degradation was monitored by High-Performance Liquid Chromatography (HPLC) using an Eclipse XDB-C18 column (150 × 3.0 mm, 3.5 µm) and a mobile phase composed of 94% water (phosphate buffer at pH = 3.6) and 6% acetonitrile, with a DAD detection at λ = 343 nm. The effect of different gamma radiation doses (from 0.05 to 3 kGy) was investigated. Chromatographic analysis shows that 1 kGy dose is effective to degrade completely HCQ at 20 ppm and following a first-pseudo-kinetic order with a dose constant corresponding to 4.2 kGy-1. A comparison was done between gamma degradation and other methods. LC-QToF-MS/MS identified the intermediate products, and their kinetic constants were determined. A mechanism pathway was proposed for HCQ degradation under gamma irradiation.

Air pollution in Vietnam during the COVID-19 social isolation, evidence of reduction in human activities

The COVID-19 (COronaVIrus Disease) pandemic has been spreading globally and social isolation has been implemented as an effective solution to limit the spread of the pandemic before vaccines are developed successfully. The reduction of human activities during social isolation is leading to an improvement in air quality being observed worldwide. In this study, we analysed satellite TROPOMI (TROPOspheric Monitoring Instrument) NO2 (Nitrogen Dioxide) and OMI (Ozone Monitoring Instrument) NO2 products obtained from Sentinel-5P and Aura satellites, respectively, during the social isolation from 1 April 2020 to 22 April 2020 in Vietnam where air pollution is a serious environmental issue. Both TROPOMI and OMI NO2 have shown low agreement with local on-ground NO2 concentration (the correlation coefficient r equals 0.4 and 0.3 in 2020, respectively) but have had moderate correlation with each other in 2020 (r equals 0.81 for two annual averaged maps). In addition, the moderate available data ratio over cloudy northern areas were observed, especially for TROPOMI datasets. During social isolation, the national average NO2 decreased by 9.3% for TROPOMI and 7.2% for OMI, respectively, in comparison with the same periods in the previous years. The reduction was stronger in the North than in the South and lasted for one more month after the lockdown period. The decrease of NO2 density during the lockdown was observed strongly in urban areas associated with dense population, traffic density, and industrial zones. Further analysis of NO2 density for Ho Chi Minh city revealed a decreasing trend of NO2 during social isolation (16.62% and 11.77% compared with the previous month and the same period in 2019, respectively). Furthermore, we used a random forest model to estimate the NO2 density (normal life situations) based on daily meteorological data at station. During social isolation, NO2 density observed in Ho Chi Minh city decreased by 26% down to that of normal life situations. The NO2 reduction has shown strong anthropogenic impact on air pollution over the study area. Besides, the first use of TROPOMI and OMI NO2 products together has highlighted potentials of satellite observation for air quality monitoring and analysis in Vietnam where on-ground measurements are very limited. © 2021 Informa UK Limited, trading as Taylor & Francis Group.