Economic Policy Uncertainty, Energy and Sustainable Cryptocurrencies: Investigating Dynamic Connectedness during the COVID-19 Pandemic

The purpose of the research is to explore the dynamic multiscale linkage between economic policy uncertainty, equity market volatility, energy and sustainable cryptocurrencies during the COVID-19 period. We use a multiscale TVP-VAR model considering level (EPUs and IDEMV) and returns series (cryptocurrencies) from 1 December 2019 to 30 September 2022. The data are then decomposed into six wavelet components, based on the wavelet MODWT method. The TVP-VAR connectedness approach is used to uncover the dynamic connectedness among EPUs, energy and sustainable cryptocurrency returns. Our findings reveal that CNEPU (USEPU) is the strongest (weakest) NET volatility transmitter. IDEMV is the most consistent volatility NET transmitter among all uncertainty indices across the original returns and wavelet scales (D1~D6). Energy cryptocurrencies, i.e., GRID, POW and SNC, are more likely to receive volatility spillovers than sustainable cryptocurrencies during a turbulent period (COVID-19). XLM (XNO) is least (most) affected by volatility spillover in system-wide connectedness, and XLM (ADA and MIOTA) showed a consistent (heterogeneous) non-recipient behavior across the six wavelet (D1~D6) scales and original return series. This study uncovers the dynamic connectedness across multiscale, which will support investors considering different investment horizons (D1~D6). © 2023 by the authors.

Segmentation on Chest CT Imaging in COVID- 19 Based on the Improvement Attention U-Net Model

This paper proposes a new deep learning model to detect COVID-19 lesions in chest CT images. This method is based on the Attention U-net which uses the layer of Atrous Spatial Pyramid Pooling (ASPP) to capture the feature on various scales. It also contains an attention gate. The attention gate provides the ability to suppress irrelevant regions and focus on the useful feature in an input image. The experimental results show that this method can achieve 99.61% accuracy and 80.43% precision. They are more effectively than the baseline method on Chest CT images. © 2022 The authors and IOS Press. All rights reserved.

The Impact of Organizational Citizenship Behavior on Organizational Performance of Vietnamese Universities during the Covid-19 Pandemic: The Moderating Role of Transformational Leadership

In an organization, the relationship between leaders and employees has long been of interest not only to organizational managers but also to researchers in management science. The purpose of this study is to examine the moderating role of transformational leadership style on the impact of organizational citizenship behavior on organizational performance (case study in Vietnamese universities). We employed a mix of methodologies, including Bayesian analysis, exploratory factor analysis, and regression analysis, to achieve this objective. The results showed that organizational citizenship behavior positively impacts organizational performance at Vietnamese universities. Besides, we also found evidence that transformational leadership styles increase the positive impact of organizational citizenship behavior on organizational performance in Vietnamese universities. Theoretically, these results highlight the organizational performance elements. This finding demonstrates the managerial influence in inspiring people to contribute to the organization. Based on the research results, we also propose implications for Vietnamese universities to influence organizational citizenship behavior and transformative leadership styles to increase organizational performance. Finally, to the best of our knowledge, this is a rare study that applies Bayesian analysis in this area of research. © 2022, Success Culture Press. All rights reserved.

Continuous Purchase Intention from E-Marketplace: A case study of Organic Agricultural Products

Consumer habits and behaviours have been altered due to the Covid-19 outbreak and the emergence of new trends, ranging from proactively purchasing safe and nutritious goods to keeping necessary foods at home. This study aimed to evaluate the influence of factors that belonged to consumer perception of the organic agricultural products continuous purchase intention from the e-marketplace. The mixed research method was adopted through in-depth interviews and surveys. These research results pointed out the critical positive factors impacting the organic agricultural products continuous purchase intention from e-marketplace, including organic agricultural products knowledge, perceived price, perceived environmental protection, perceived health benefits, perceived quality, perceived policy in the Covid-19 pandemic. Some implications were proposed from the research results. © 2021 IEEE