Natural gas and the utility sector nexus in the U.S.: Quantile connectedness and portfolio implications

Given that natural gas is a vital input for the U.S. utility sector, this study empirically investigates the return connectedness between the natural gas and utility stocks in the U.S. market. Using the quantile connectedness approach, we show that the nexus between natural gas and utility stocks is more pronounced at the tails compared to the central of the conditional distribution. The return connectedness indices are time-varying with a net receiver role of natural gas and driven by various macro-variables. Finally, our portfolio implication analyses with alternative tail risk measures suggest that it can be more beneficial for risk-adverse investors to allocate substantial weights into the electricity utility stocks in normal market conditions. However, during the COVID-19- induced recession, it is critical to shift more fund to the natural gas futures to reduce tail risks. © 2023 Elsevier B.V.

The nexus between oil and airline stock returns: Does time frequency matter?

This paper investigates the relationship between oil and airline stock returns under different time frequencies. First, we propose an Autoregressive moving average model with mixed frequency exogenous variable to analyse the different impacts of oil on airline stock returns on daily, weekly, and monthly basis. We consistently find a negative oil-airline stock return nexus on a daily basis, but a positive relationship on a weekly basis. While the former supports the economic-based channel, the latter is in line with the market inertia channel. Our findings help explain mixed results reported in the literature. Further, our time frequency connectedness analysis shows that the economic-based channel dominates the market inertia channel since the connectedness is more pronounced in the short-run compared to the medium- and long-run. Our block connectedness results highlight that business models of airline firms can play a significant role in affecting the connectedness, in which the low-cost airlines are more sensitive to the oil price changes. It is worth noting that there are distinguished drivers of the oil-airline stock return nexus in different time frequencies. The drivers also vary between the Global Financial Crisis and the COVID-19 pandemic. Our results are consistent under a battery of robustness checks and deliver important implications to investors, portfolio managers, and executives of airline firms. © 2022 Elsevier B.V.

Portfolio Diversification during the COVID-19 Pandemic: Do Vaccinations Matter?☆

The COVID-19 vaccine rollout expects to mitigate the severe negative impacts of the pandemic on global financial markets. Our study provides supporting evidence for this expectation. We find robust evidence that vaccinations significantly reduce the cross-country stock volatility connectedness among G7 nations, suggesting that the diversification benefits of an international equity portfolio may be enhanced during the pandemic when vaccinations accelerate. We present two explanations for this result. First, the vaccine deployment improves stock market return and decreases individual stock market volatility. Second, the vaccine rollout helps a country's stock market be more resilient to exogenous shocks. We further demonstrate that a global portfolio using a tactical allocation rule based on the intensity of vaccinations can outperform a buy-and-hold portfolio in terms of risk-adjusted returns.

A comparative study of isothermal nucleic acid amplification methods for SARS-CoV-2 detection at point-of-care

COVID-19, caused by the novel coronavirus SARS-CoV-2, has put most of the world under lockdown. Despite approved vaccines, COVID-19 cases, hospitalizations, and deaths have remained on the rise. Rapid diagnosis and necessary public health measures are still key parts to contain the pandemic. Here, the colorimetric isothermal nucleic acid amplification tests (iNAATs) for SARS-CoV-2 detection based on loop-mediated isothermal amplification (LAMP), cross-priming amplification (CPA), and polymerase spiral reaction (PSR) were designed and compared in performance for the first time. The findings showed that, for the detection of SARS-CoV-2 genomic-RNA, LAMP outperformed both CPA and PSR, reaction mix exhibiting the limit of detection (LOD) of roughly 43.14 copies/reaction. The results can be read with the naked eye within 45 minutes, without cross-reactivity to closely related coronaviruses. The direct detection of SARS-CoV-2 RNA in simulated specimens by iNAATs was also successful. Additionally, the lyophilized reagents for LAMP reactions maintained the sensitivity and LOD of the liquid assays. The colorimetric LAMP assay was validated using clinical samples, showing 98.1% sensitivity and 100% specificity upon using extracted samples and 82.4% sensitivity and 86.2% specificity upon using unextracted specimens. The results indicate that the direct colorimetric LAMP assay developed is highly suitable for detecting SARS-CoV-2 at point-of-care.

A novel design of a smart interactive guiding robot for busy airports

The COVID-19 pandemic has had a massive impact on the global aviation industry. As a result, the airline industry has been forced to embrace new technologies and procedures in order to provide a more secure and bio-safe travel. Currently, the role of smart technology in airport systems has expanded significantly as a result of the contemporary Industry 4.0 context. The article presents a novel construction of an intelligent mobile robot system to guide passengers to take the plane at the departure terminals at busy airports. The robot provides instructions to the customer through the interaction between the robot and the customer utilizing voice communications. The usage of the Google Cloud Speech-to-Text API combined with technical machine learning to analyze and understand the customer's requirements are deployed. In addition, we use a face detection technique based on Multi-task Cascaded Convolutional Networks (MTCNN) to predict the distance between the robot and passengers to perform the function. The robot can guide passengers to desired areas in the terminal. The results and evaluation of the implementation process are also mentioned in the article and show promise.

COVID-19 Disease Classification by Cough Records Analysis using Machine Learning

The rapid spreading rate of the Coronavirus disease 2019 (COVID-19) has resulted in more than 6.2 million deceased cases. Furthermore, the patients of the latest Omicron variation carry light to almost no symptoms of the disease themselves. Thus, the requirement for a new diagnosis method besides Reverse Transcription-Polymerase Chain Reaction (RT-PCR) becomes the most important step to successfully detect infected cases. In this research, the application of the KNN, Ensemble and SincNet models are implemented as the main models for classification diagnosis based on cough sound records of infected patients. After pre-processing steps for removing silence ranges in the audio scripts, the cough sounds are augmented, subsequently separated into single cough samples, then generated 3 testing scenarios for dealing with the imbalanced problem between the sample classes. Afterward, MelFrequency information and MelSprectrogram are extracted as main features for analysis in order to distinguish patients with COVID-19 disease and healthy cases. The AICV115M dataset consisting of two classes COVID-19 and NonCOVID-19 is implemented for performance evaluation. The recorded highest accuracy on the models KNN, Ensemble and SincNet are 92.49%, 90.1% and 85.15%, respectively. © 2022 IEEE.

Evaluation of the efficacy and tolerance of a cosmetic serum containing volcanic mineralizing water, probiotic fractions, hyaluronic acid, niacinamide, and tocopherol in patients with “face mask dermatitis”

Background: The treatment of “face mask dermatitis” (FMD) is an emerging issue gaining importance due to increased use of mouth-nose protection in everyday life during COVID-19 pandemic. Cosmeceuticals, care components containing active ingredients, play a growing role in treatment plans to protect skin’s natural barrier function. However, well-designed studies on their efficacy and limitations are widely missing. Objective: Evaluation of the efficacy of a serum containing volcanic mineralizing water (VMW), probiotic fractions (Vitroscella filiformis), hyaluronic acid, niacinamide and tocopherol applied twice daily in patients with FMD employing objective and subjective methodology. Methods: A randomized, controlled trial was conducted. At baseline (visit V0) and after 4 weeks of product use (V1), dermatologic investigations were performed, using skin function tests, optical coherence tomography measurements, clinical severity assessments of facial lesions, and standardized questionnaires. Results: The patient cohort comprised 50 females with FMD (mean age 30 years ± 4.73 SD). In the intervention group (n = 40) there was a significant improvement in erythema (P =.000), scaling (P =.001) and papules (P =.000) compared with the control group (n = 10). Morever, patients in the intervention group reported a significant decrease in subjective symptoms, especially facial itching compared with the control group (P =.041). Instrumental measures showed a significant improvement of skin hydration (P =.023;P =.014) and skin elasticity (P =.024;P =.024). Conclusions: The use of a dedicated cosmeceutical cosmetic serum in a population with facial mask dermatitis resulted above all in an improvement of facial erythema and a relief of subjective symptoms especially itch.

What is the future of the bank branch in the midst of the 4.0 industrial revolution? Answers from Vietnam

Digital channels (websites, bank apps, mobile banking) are incrementally improving as a result of technology innovation and changing customer behavior. The unprecedented Covid-19 pandemic has just added to this trend by urging people to work and make all financial transaction through the Internet. In this context, the question arises of whether banks should revive their physical branches or take the opportunity to shift to mainly digital platform? This research focuses on the branch network trend of Vietnamese commercial banks during the period 2012–2019 to answer the question, what is the contribution of bank branch networks to the banks’ profits. Panel data from 22 largest Vietnamese commercial banks in terms of owners’ capital has been analyzed, using Random Effect Model (REM) regression models. The results show that Vietnamese banks are still expanding their branch networks, despite the fact that bank customers are increasingly engaging in digital bank services. The number of branches has a positive correlation with the banks’ profits, although there is a disparity between large network banks and the rest. The research suggests some implications that can help optimize the branch network in the context of digitalization in an emerging market. © Thuy Thu Pham, Hien Thi Thu Hoang, Ha Thi Thu Do, 2022.

FACTORS DETERMINING THE DEGREE OF THE IMPACT OF THE COVID-19 PANDEMIC ON SMALL AND MEDIUM ENTERPRISES IN VIETNAM

Human lives all over the world had changed in unprecedented ways due to the COVID-19 pandemic. In Vietnam, efforts to control said pandemic coupled with businesses’ efforts to change for their survival and preparation of post-pandemic recovery have brought certain achievements. This chapter examines how small and medium enterprises (SMEs) in Vietnam had been affected by the pandemic and what the factors that determined the degree of impact the pandemic had on SMEs were, and how SMEs had been supported by the Vietnamese government during the crisis. Based on data drawn from organizations’ business surveys, we discussed the pandemic’s impact on SMEs and its transmission channels. We also explored SMEs’ plight through reports and indexes from national statistics and through voices from victims. We then advanced the model to identify the factors that determined the degree of impact the pandemic had on SMEs. The chapter concludes that most SMEs in Vietnam suffered from the COVID-19 pandemic, four factors that determined the degree of impact the pandemic had on SMEs were: A decrease in financial resources;a decrease in working hours and wages;a decrease in demand;lack of government support. This chapter also suggests that policies for supporting SMEs should be simple regarding their implementation. To achieve successful digital transformation, SMEs should be supported by the government in technical knowledge training and fundraising, as this was proven to have relieved the impact of the COVID-19 pandemic for enterprises. © 2022 by Nova Science Publishers, Inc.

The Effect of Foreign Direct Investment Inflow on Exports: Evidence from Vietnam

Foreign direct investment (FDI) and export are now often regarded as two of the most important drivers of economic growth on a worldwide scale. The impact of foreign direct investment on Vietnam's exports is investigated in this study. The data for the time period 1985-2020 was obtained from the World Bank and the Vietnam General Statistics Office. The years 1985 to 2020 were chosen to evaluate the evolution of macroeconomic parameters since 1986. The impact of the Covid-19 epidemic on renovation reform. The Johansen co-integration test proved that FDI and domestic investment (DI) had a long-term positive impact on Vietnam's export growth. The Granger causality test revealed that there is a one-way relationship between FDI and export in the near term, but no such relationship exists between DI and export. The result of the variance decomposition study demonstrates that the FDI sector has a bigger impact on Vietnam's export growth than the DI sector. Furthermore, export activities are vulnerable to FDI sector shocks. As a result, in recent years, FDI has been regarded as the most important factor of export growth in Vietnam.

Combination therapy protects macaques against advanced Marburg virus disease.

Monoclonal antibodies (mAbs) and remdesivir, a small-molecule antiviral, are promising monotherapies for many viruses, including members of the genera Marburgvirus and Ebolavirus (family Filoviridae), and more recently, SARS-CoV-2. One of the major challenges of acute viral infections is the treatment of advanced disease. Thus, extending the window of therapeutic intervention is critical. Here, we explore the benefit of combination therapy with a mAb and remdesivir in a non-human primate model of Marburg virus (MARV) disease. While rhesus monkeys are protected against lethal infection when treatment with either a human mAb (MR186-YTE; 100%), or remdesivir (80%), is initiated 5 days post-inoculation (dpi) with MARV, no animals survive when either treatment is initiated alone beginning 6 dpi. However, by combining MR186-YTE with remdesivir beginning 6 dpi, significant protection (80%) is achieved, thereby extending the therapeutic window. These results suggest value in exploring combination therapy in patients presenting with advanced filovirus disease.

International business research and scholarship in the Middle East: developments and future directions

In this introduction we review the extant literature that demonstrate the importance of the Middle Eastern institutional and cultural context in shaping international business’s (IB) strategies and practices across several countries. Drawing on the literature, as well as the five articles included in this special issue, we (1) outline the state of socio-cultural, historical and economic forces that shape international business in several Middle Eastern nations;(2) utilize institutional theory to evaluate the constraints of international business practices in the Middle East;and (3) highlight the key gaps in the literature and the challenges faced by IB scholars and practitioners in the Middle East. We subsequently propose an agenda for future research in order to lay the foundation for international business scholars to advance the theorizing and application of IB practices in the Middle East context. © 2021 The Author(s). Published with license by Taylor & Francis Group, LLC.