ABSTRACT
This paper examines the relations among AI service attributes, brand image, brand familiarity and customer equity. The proposed relationships were tested by structural equation modeling of survey data of 210 usable responses in China. Test results indicate that problem-solving ability, accuracy, and customization of AI service have significant positive effects on brand image;the three constructs of customer equity (value equity, brand equity, and relationship equity) are all positively and strongly affected by brand image. Moreover, brand familiarity moderates the effect of customization, interaction, and problem-solving ability on brand image. By bringing together AI literature and consumer behavior literature, this research sheds light on the effectiveness of AI service in enhancing brand image and customer equity. This has important theoretical value in enriching the streams of AI and brand research. Additionally, this research integrates the AI technology within a corporate brand management strategy and offers practitioners and marketers in post-COVID era with a model with which they can find new ways to meet consumer demands and improve brand image via AI technology. © 2022, The Author(s), under exclusive licence to Springer Nature Limited.
ABSTRACT
In our complex social environments, life situations are ever-changing. When dealing with these changes, there is no one-size-fits-all response or regulatory strategy suitable for all situations. Emotion regulation flexibility (ERF)—a framework for understanding individual differences in adaptive responding to ever-changing life contexts—emphasizes that individuals can flexibly deploy and adjust emotion regulation strategies according to specific characteristics of stressful situations in daily life. To achieve regulatory efficacy, it is important that one can utilize a balanced profile of ER strategies and select strategies that fit well with particular stressful situations. Specifically, using multiple ER strategies in daily life, rather than relying on only single-strategies, would indicate higher ERF. Additionally, based on leading models of strategy-situation fit, certain ER strategies are more appropriate for high versus low intensity stressful events. For instance, distraction involves with shielding oneself from negative stimuli and replacing them with irrelevant things, which may have a greater regulatory effect in high-intensity negative situations. Conversely, strategies such as reappraisal, which involves the processing of negative situations through deep cognitive change, may be more effective in lower-intensity negative situations and as a cornerstone of longer-term ER. We used the experience-sampling method (ESM) to quantify individual's ERF;more specifically we assess participants for 1) having more or less balanced ER strategy profiles and 2) showing greater strategy-situation fit, in regard to the use of distraction versus reappraisal in the regulation of high-intensity versus low-intensity negative life events. To test the adaptive value of ERF on negative emotions and mental health, we investigated the influence of ERF on depressive and anxiety symptoms in two samples. We hypothesized that individuals with a more balanced profile of ER strategy use and a great level of strategy-situation fit would have higher levels of mental health, indicated by low levels of anxiety and depressive feelings. In sample 1, two hundred eight college students finished the ESM procedure (2859 beeps). Intensity of negative situations was measured by self-reported negative feelings for the time points where participants reported an adverse event. Simultaneously, we assessed participants' use of two ER strategies (i.e., distraction and reappraisal). Considering the negative impact of COVID-19 on people's daily life, we collected another sample (sample 2, 3462 beeps) with one hundred people who lived in Hubei Province, where Wuhan was in lockdown during the severe phase of COVID-19 (March 7-13, 2020). We measured intensity of negative situations (by averaging individuals' negative feelings), as well as the use of two ER strategies at corresponding time points. After completing the ESM procedure, the participants were asked to fill out a series of emotional health questionnaires, including Beck Depression Inventory-II, Beck Anxiety Inventory and Spielberger State Anxiety Scale. Multilevel models were used to fit the covariation between the use of distraction versus reappraisal ER strategies and the intensity of negative events. Additionally, we used multiple level regression models to test whether high level of strategy-situation fit would result in lower negative feelings. To test whether a single-strategy preference would lead to higher levels of anxiety and depressive feelings compared to a multiple-strategy preference, latent profile analyses (LPA) was used. Results from the LPA indicated that individuals with preferences for rumination and express suppression reported higher levels depression and anxiety than individuals with a multi-strategy preference. In the multilevel models, results of the two independent samples both suggested individuals who were more inclined to use a higher level of distraction in response to high-intensity negative situations (e.g., adverse events or during COVID-19) and use hi her levels of reappraisal during low-intensity situations (i.e., high level of ERF) reported lower levels of anxiety and depressive feelings. On the converse, individuals who tended to use more distraction in low intensity situations and more reappraisal in high intensity situations, (i.e., those showing lower ERF) reported a higher level of negative feelings. Together, our findings revealed a negative relationship between ERF and mental health problems in two samples, suggesting that having balanced ER profiles and flexibly deploying strategies in specific life contexts may have adaptive value in facilitating positive mental health. This work deepens our understanding of the interaction between ER strategies and situational demands, paving the way for future intervention research to help alleviate negative emotions associated with affective disorders or the experience of major traumatic events (such as epidemics, earthquakes, etc.). © The Authors.
ABSTRACT
Video represents the majority of internet traffic today, driving a continual race between the generation of higher quality content, transmission of larger file sizes, and the development of network infrastructure. In addition, the recent COVID-19 pandemic fueled a surge in the use of video conferencing tools. Since videos take up considerable bandwidth ( ∼ 100 Kbps to a few Mbps), improved video compression can have a substantial impact on network performance for live and pre-recorded content, providing broader access to multimedia content worldwide. We present a novel video compression pipeline, called Txt2Vid, which dramatically reduces data transmission rates by compressing webcam videos ('talking-head videos') to a text transcript. The text is transmitted and decoded into a realistic reconstruction of the original video using recent advances in deep learning based voice cloning and lip syncing models. Our generative pipeline achieves two to three orders of magnitude reduction in the bitrate as compared to the standard audio-video codecs (encoders-decoders), while maintaining equivalent Quality-of-Experience based on a subjective evaluation by users ( n=242 ) in an online study. The Txt2Vid framework opens up the potential for creating novel applications such as enabling audio-video communication during poor internet connectivity, or in remote terrains with limited bandwidth. The code for this work is available at https://github.com/tpulkit/txt2vid.git. © 1983-2012 IEEE.
ABSTRACT
One–step preparation of electrospun bimodal fibrous membrane based on single nozzle is the key to the efficient fabrication of high–performance air filter. However, the preparation mechanism of electrospun bimodal fibers at low conductivity solution system is not clear, and there is a lack of evaluation methods for the quality of bimodal nanofibers, which limits the applicability of single nozzle electrospinning and the preparation efficiency of electrospun bimodal fibers. Here, three electrospinning processes at low conductivity solution systems of polyamide–6 (PA6), PA6 blended PVP (PA6/PVP), and PA6 blended polyethylene oxide (PA6/PEO) were studied according to the rheological properties and the fluid electrics (i.e., zeta potential), and the quality of the prepared bimodal fibrous membrane was creatively evaluated by R value. Inhomogeneous phase separations of the electrospinning jet along the direction parallel (x–axis) or perpendicular (y–axis) to the electric field were responsible for the formation of bimodal fibers. In addition, for the same solution system, the R value had a positive correlation with the air filtration performance. This work will greatly enhance the applicability of one–step single nozzle electrospinning for the preparation of bimodal nanofibers, improve the preparation efficiency, and promote the development of high–performance air filter. © 2022 Elsevier Ltd
ABSTRACT
Since the COVID-19 outbreak in late 2019, a surprisingly large amount of personal protective equipment, such as medical rubber gloves, have been frequently used, and this medical waste can cause very major environmental problems. A multidisciplinary collaborative approach is needed to combat the pandemic and lessen the environmental risks associated with the disposal of medical waste. This study developed an innovative approach by incorporating shredded rubber glove fibers (RGF) into aggregates to enhance the fatigue resistance of concrete. In this study, different volume contents (0.5%, 1.0%, 1.5%, 2.0%) of RGF were added to the aggregate for the first time. The effects of different RGF contents on the fatigue characteristics of concrete were examined through repeated loading tests and SEM analysis. The results show that the width and number of cracks produced by rubber glove fiber concrete (RGFC) after repeated loading are significantly reduced compared with normal concrete (NC). Following repeated loading, RGFC exhibited higher total, plastic, and elastic strain values than NC, demonstrating greater deformability and elasticity. However, the maximum total strain growth rate and the total strain growth range of the RGFC group were only 2.26 × 10−3/time and 14.0%, which were significantly smaller than the 3.8 × 10−3/time and 31.7% of the NC group, showing better stability, corresponding to enhance the fatigue resistance of concrete. The interfacial transition zone (ITZ) was abnormally smooth with a thin thickness and no visible gaps were discovered, based on the results of SEM test performed on the RGFC. The findings obtained in this study may provide new ideas for the resource utilization of medical waste. © 2023
ABSTRACT
The pandemic outbreak of COVID-19 has posed a threat to public health globally, and rapid and accurate identification of the viruses is crucial for controlling COVID-19. In recent years, nanomaterial-based electrochemical sensing techniques hold immense potential for molecular diagnosis with high sensitivity and specificity. In this review, we briefly introduced the structural characteristics and routine detection methods of SARS-CoV-2, then summarized the associated properties and mechanisms of the electrochemical biosensing methods. On the above basis, the research progress of electrochemical biosensors based on gold nanomaterials, oxide nanomaterials, carbon-based nanomaterials and other nanomaterials for rapid and accurate detection of virus were reviewed. Finally, the future applications of nanomaterial-based biosensors for biomolecular diagnostics were pointed out.
ABSTRACT
This study investigates the effect of social distancing on the local bias of institutional investors. Using SafeGraph's Social Distancing Metrics data and SEC's EDGAR 13F filings, we find that stay-at-home duration ratio decreases institutional investors' local holdings and firms' institutional ownership in the U.S. We also exploit the lockdown orders across various states during the COVID-19 pandemic as exogenous shocks to conduct the stacked regression estimation, which yields a similar result. Our channel analysis using abnormal return indicates that social distancing mitigates local bias by constraining the information advantage of local investors rather than alleviating their cognitive bias. © 2022 Elsevier Inc.
ABSTRACT
COVID-19 seriously affects the tourism and hospitality industry. In this study, we investigate the behavior of 40 tourism and hospitality stock market indices worldwide from two perspectives. First, empowered by the Granger causality test and network analysis, we test the spillover effects among these stock markets and find that the dynamics of interconnectedness network structures differ significantly in the pre-pandemic and in-pandemic periods. Second, we employ econometric models to explore how the influence of COVID-19 on these stock markets varies by considering the interconnectedness structure, the government response stringency index, and other country-level characteristics. We find that the interconnectedness structure significantly and robustly affects stock returns in the tourism and hospitality markets. Our investigation provides a better understanding of the impact of COVID-19 on tourism and hospitality industry. © 2022 Elsevier Inc.
ABSTRACT
Purpose: This research aims to figure out whether the pool testing method of SARS-CoV-2 for COVID-19 is effective and the optimal sample size is in one bunch. Additionally, since the infection rate was unknown at the beginning, this research aims to propose a multiple sampling approach that enables the pool testing method to be utilized successfully. Design/methodology/approach: The authors verify that the pool testing method of SARS-CoV-2 for COVID-19 is effective under the situation of the shortage of nucleic acid detection kits based on probabilistic modeling. In this method, the testing is performed on several samples of the cases together as a bunch. If the test result of the bunch is negative, then it is shown that none of the cases in the bunch has been infected with the novel coronavirus. On the contrary, if the test result of the bunch is positive, then the samples are tested one by one to confirm which cases are infected. Findings: If the infection rate is extremely low, while the same number of detection kits is used, the expected number of cases that can be tested by the pool testing method is far more than that by the one-by-one testing method. The pool testing method is effective only when the infection rate is less than 0.3078. The higher the infection rate, the smaller the optimal sample size in one bunch. If N samples are tested by the pool testing method, while the sample size in one bunch is G, the number of detection kits required is in the interval (N/G, N). Originality/value: This research proves that the pool testing method is not only suitable for the situation of the shortage of detection kits but also the situation of the overall or sampling detection for a large population. More importantly, it calculates the optimal sample size in one bunch corresponding to different infection rates. Additionally, a multiple sampling approach is proposed. In this approach, the whole testing process is divided into several rounds in which the sample sizes in one bunch are different. The actual infection rate is estimated gradually precisely by sampling inspection in each round. © 2021, Emerald Publishing Limited.
ABSTRACT
In this paper, we formulate a special epidemic dynamic model to describe the transmission of COVID-19 in Algeria. We derive the threshold parameter con-trol reproduction number (R0c), and present the effective control reproduction number (Rc(t)) as a real-time index for evaluating the epidemic under different control strate-gies. Due to the limitation of the reported data, we redefine the number of accumu-lative confirmed cases with diagnostic shadow and then use the processed data to do the optimal numerical simulations. According to the control measures, we divide the whole research period into six stages. And then the corresponding medical resource estimations and the average effective control reproduction numbers for each stage are given. Meanwhile, we use the parameter values which are obtained from the optimal numerical simulations to forecast the whole epidemic tendency under different control strategies.
ABSTRACT
Nowadays, malignant brain tumors are still mostly lethal diseases with poor prognosis and a clinical median survival rate of fewer than 2 years after therapeutic intervention. It is difficult to achieve complete remission of brain tumors due to blood-brain barrier (BBB) and a lack of efficient drug delivery systems to targeted transportation of brain tumor medicines. Nanoparticle delivery systems have shown merits including stability and high carrier capacity for the transportation of different drugs to treat brain tumors. The application of mRNA nanomedicines brings in great promise not only in COVID-19, but also for malignant brain tumor immunotherapy. The appropriate delivery system facilitates mRNA delivery efficiency and enhances the immune response successfully, for optimal treatment outcomes on malignant brain tumors. Herein, we do an updated review on the development of mRNA nanomedicines for malignant brain cancer treatment. We focus on how to design mRNA-loaded nanoparticle-based delivery systems with optimized pharmacokinetics and pharmacodynamics for efficient therapy of brain cancers. In addition, we point out the challenges and solutions for further development of mRNA nanomedicines for brain cancer therapy. We hope this review would stimulate interest among researchers with different backgrounds and expedite the translation from bench to bedside for the mRNA nanomedicines. © 2022 The Authors
ABSTRACT
Far UV-C, informally defined as electromagnetic radiation with wavelengths between 200 and 230 nm, has characteristics that are well-suited to control of airborne pathogens. Specifically, Far UV-C has been shown to be highly effective for inactivation of airborne pathogens;yet this same radiation has minimal potential to cause damage to human skin and eye tissues. Critically, unlike UV-B, Far UV-C radiation does not substantially penetrate the dead cell layer of skin (stratum corneum) and does not reach germinative cells in the basal layer. Similarly, Far UV-C radiation does not substantially penetrate through corneal epithelium of the eye, thereby preventing exposure of germinative cells within the eye. The most common source of Far UV-C radiation is the krypton chloride excimer (KrCl*) lamp, which has a primary emission centered at 222 nm. Ozone production from KrCl* lamps is modest, such that control of indoor ozone from these systems can be accomplished easily using conventional ventilation systems. This set of characteristics offers the potential for Far UV-C devices to be used in occupied spaces, thereby allowing for improved effectiveness for inactivation of airborne pathogens, including those that are responsible for COVID-19. © 2022 The Author(s). Published with license by Taylor & Francis Group, LLC.
ABSTRACT
Aquaculture is regarded as one of the fastest methods for preparing food and may be relied upon more and more in the future. Production can be seeded from fish caught in the wild and can be maintained with imported fish food however, aquaculture output and quality is limited by cost and resources, and there is an incentive to make it more environmentally sustainable. If these goals can be achieved, we will produce better quality fish and in higher volumes. Microbial protein feed (MPF) offers a sustainable feedstuff solution for the aquaculture industry in China, with the net benefits of taking less time to prepare, using less water and land, being recyclable and also reducing carbon emissions. MPF provides stable and high quality proteins and is produced through the fermentation of microorganisms by utilizing agricultural and industrial waste as substrates and been extensively used in fish and shrimp production in China. This review describes the microorganisms, raw materials, fermentation processes and nutritional components used in MPF production in aquaculture. We shall discuss also MPF large-scale production processes in detail and then finally, what opportunities and challenges are faced by MPF in Chinese aquaculture in the context of "double carbon"targets and Covid-19. High-efficiency biosynthesis technology using mono-carbon gases to produce protein will become an important field in the future, as it shall facilitate sustainable and healthy feedstocks for the aquaculture industry, and allow China to achieve the goal of lower carbon emissions. © 2023 Elsevier Ltd.
ABSTRACT
The far infrared (1 similar to 10 THz) and mid-infrared (400 similar to 4 000 cm(-1)) spectra of six common antibiotics (Ofloxacin capsules, Ofloxacin tablets, Norfloxacin capsules, Azithromycin tablets, Roxithromycin tablets and Levofloxacin hydrochloride tablets), three antiviral drugs for COVID-19 (Ribavirin tablets, Abidol hydrochloride tablets and Chloroquine phosphate tablets) and an expectorant drug (Ambroxol hydrochloride tablets) within shelf-life were studied. The effects of vehicles and another high temperature environment (65 degrees C) on the structure and crystal form of drugs were simulated and fed back to the changes in infrared spectra. After two months of continuous experiments, it was found that the structure and crystal form of other drugs had hardly changed except in ambroxol hydrochloride tablets. When capsule drugs were placed in high-temperature environment for a long time, the epidermis would become brittle and easy to rupture, but the efficacy of internal drugs had hardly changed. Taking fluoroquinolone antibiotics (Ofloxacin and Norfloxacin) as examples, combined with density functional theory (DFT) and the potential energy distribution (PED) method, the theoretical infrared spectra of the two antibiotics monomers, polymers and crystals were calculated by Crystal 14 and Gaussian 16 software with B3LYP/6-311++G(d,p) basis set. The vibrational modes and their contribution rates corresponding to all characteristic peaks were obtained, and the experimental spectrum was accurately identified. It was also found that from monomer to polymer and then to crystal, the stacking force (pi-pi interaction) between lattices accounted for the largest proportion of inter-molecular interaction, more than 90%. Therefore, the theoretical calculation was more consistent with the experimental results only when the crystal with periodic boundary conditions was taken as the initial configuration. The vibrational modes in the far infrared band mainly came from the collective vibration of molecules (vibration accounts for more than 99%, rotation and translation account for less than 1%), and the out-of-plane bending caused by inter-molecular hydrogen bond and Van der Waals force contributes the most, more than 90%. In the mid-infrared band, there were also a certain proportion of inter-molecular interactions. For example, the peaks of norfloxacin at 1 440 cm(-1) and ofloxacin at 1 524 cm(-1) can only be reproduced in the theoretical spectrum with the crystal as the configuration, respectively, from the collective vibration and the stretching of O-H center dot center dot center dot O bonds.
ABSTRACT
With the outbreak of the Covid-19 epidemic and the normalization of epidemic prevention, various epidemic prevention equipment has been used in all walks of life. In terms of delivering medicines to patients, the intelligent tracing medicine delivery car plays an important role. The car takes the STC89C52 microcontroller as the core of the intelligent car, adopts the L298N as the chip of the electric drive, and selects the DHT11 temperature and humidity sensor as the temperature and humidity detection. The car includes a line patrol module, an obstacle avoidance module, a temperature-humidity monitoring module, a display module, an infrared module, an alarm module, a drive module and a key module, etc. Finally, intelligent car realizes these functions, such as tracing the black line, avoiding obstacles by infrared, alarm, monitoring temperature and humidity, and displaying temperature and humidity. © 2022 ACM.
ABSTRACT
The COVID-19 outbreak that began in 2020 has changed human activities and thus reduced anthropogenic carbon emissions in most parts of the world. To accurately study the impact of the COVID-19 pandemic on changes in atmospheric XCO2 concentrations, a data fusion method called High Accuracy Surface Modeling (HASM) is applied using the CO2 simulation from GEOS-Chem as the driving field and GOSAT XCO2 observations as the accuracy control conditions to obtain continuous spatiotemporal global XCO2 concentrations. Cross-validation shows that using High Accuracy Surface Modeling greatly improves the mean absolute error and root mean square error of the XCO2 data compared with those for GEOS-Chem simulation data before fusion, and the R (2) is also increased from 0.54 to 0.79 after fusion. Moreover, OCO-2/OCO-3 XCO2 observational data verify that the fused XCO2 data achieve a lower MAE and RMSE. Spatiotemporal analysis shows that the global XCO2 concentration exhibited no obvious trend before or after the COVID-19 outbreak, but the growth of global and terrestrial atmospheric XCO2 in 2020 can reflect the impact of the COVID-19 pandemic;that is, the rapid growth in terrestrial atmospheric XCO2 observed before 2019 slowed, and high-speed growth resumed in 2021. Finally, obvious differences in the pattern of XCO2 growth are found on different continents.
ABSTRACT
Black swan events such as the coronavirus (COVID-19) outbreak cause substantial supply chain disruption risks to modern companies. In today's turbulent and complex business environment, supply chain resilience and robustness as two critical capabilities for firms to cope with disruptions have won substantial attention from both the academia and industry. Accordingly, this study intends to explore how digitalization helps build supply chain resilience and robustness. Adopting organizational information processing theory, it proposes the mediating effect of supply chain collaboration and the moderating effect of formal contracts. Using survey data of Chinese manufacturing firms, the study applied structural equation modelling to test the research model. Results show that digitalization has a direct effect on supply chain resilience, and supply chain collaboration can directly facilitate both resilience and robustness. Our study also indicates a complementary mediating effect of supply chain collaboration on the relationship between digitalization and supply chain resilience and an indirect-only mediation effect on the relationship between digitalization and supply chain robustness. Findings reveal the differential roles of digitalization as a technical factor and supply chain collaboration as an organizational factor in managing supply chain disruptions. Paradoxically, formal contracts enhance the relationship between digitalization and supply chain resilience but weaken the relationship between supply chain collaboration and supply chain resilience. The validation of moderating effects determines the boundary conditions of digitalization and supply chain collaboration and provides insights into governing supply chain partners' behavior. Overall, this study enhances the understanding on how to build a resilient and robust supply chain.
ABSTRACT
Under the influence of the fifth industrial revolution and the outbreak of COVID-19, the digital transformation of enterprises has entered a new stage of rapid development. Digital transformation has become the trend of enterprise operation in the digital economy era. In this context, enterprise laboratory asset operation has also become an important aspect of enterprise digital operation. It is urgent to build a set of enterprise laboratory asset digital evaluation system to assist the implementation of enterprise digital strategy. Based on the characteristics of laboratory assets and the closed-loop theory of asset operation management, this paper analyzes and studies the laboratory asset management, establishes a targeted evaluation index system of digital asset management, focuses on the composition of the digital operation system of laboratory assets, and constructs a management index evaluation system of assets, efficiency, cost and other dimensions, so as to create a real-time, comprehensive and comprehensive evaluation system The closed-loop and full cycle digital management ecological environment realizes the effective integration of laboratory resource fragmentation information and the complete embodiment of digitization, provides service support for continuously improving asset management performance, and provides support for further improving enterprise economic efficiency and operation level. © 2022 SPIE.
ABSTRACT
Recently, the viral propagation of mis/disinformation has raised significant concerns from both academia and industry. This problem is particularly difficult because on the one hand, rapidly evolving technology makes it much cheaper and easier to manipulate and propagate social media information. On the other hand, the complexity of human psychology and sociology makes the understanding, prediction and prevention of users' involvement in mis/disinformation propagation very difficult. This themed series on "Multi-Disciplinary Dis/Misinformation Analysis and Countermeasures" aims to bring the attention and efforts from researchers in relevant disciplines together to tackle this challenging problem. In addition, on October 20th, 2021, and March 7th 2022, some of the guest editorial team members organized two panel discussions on "Social Media Disinformation and its Impact on Public Health During the COVID-19 Pandemic," and on "Dis/Misinformation Analysis and Countermeasures - A Computational Viewpoint." This article summarizes the key discussion items at these two panels and hopes to shed light on the future directions.