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1.
Kongzhi yu Juece/Control and Decision ; 38(3):699-705, 2023.
Article in Chinese | Scopus | ID: covidwho-20245134

ABSTRACT

To study the spreading trend and risk of COVID-19, according to the characteristics of COVID-19, this paper proposes a new transmission dynamic model named SLIR(susceptible-low-risk-infected-recovered), based on the classic SIR model by considering government control and personal protection measures. The equilibria, stability and bifurcation of the model are analyzed to reveal the propagation mechanism of COVID-19. In order to improve the prediction accuracy of the model, the least square method is employed to estimate the model parameters based on the real data of COVID-19 in the United States. Finally, the model is used to predict and analyze COVID-19 in the United States. The simulation results show that compared with the traditional SIR model, this model can better predict the spreading trend of COVID-19 in the United States, and the actual official data has further verified its effectiveness. The proposed model can effectively simulate the spreading of COVID-19 and help governments choose appropriate prevention and control measures. Copyright ©2023 Control and Decision.

2.
ACM Web Conference 2023 - Companion of the World Wide Web Conference, WWW 2023 ; : 1190-1195, 2023.
Article in English | Scopus | ID: covidwho-20238633

ABSTRACT

The COVID-19 pandemic has had a significant impact on human behaviors and how it influenced peoples' interests in cultural products is an unsolved problem. While prior studies mostly adopt subjective surveys to find an answer, these methods are always suffering from high cost, limited size, and subjective bias. Inspired by the rich user-oriented data over the Internet, this work explores the possibility to leverage users' search logs to reflect humans' underlying cultural product interests. To further examine how the COVID-19 mobility policy might influence cultural interest changes, we propose a new regression discontinuity design that has the additional potential to predict the recovery phase of peoples' cultural product interests. By analyzing the 1592 search interest time series in 6 countries, we found different patterns of change in interest in movies, music, and art during the COVID-19 pandemic, but a clear overall incremental increase. Across the six countries we studied, we found that changes in interest in cultural products were found to be strongly correlated with mobility and that as mobility declined, interest in movies, music, and art increased by an average of 35, 27 and 20, respectively, with these changes lasting at least eight weeks. © 2023 ACM.

3.
Thin Solid Films ; 774, 2023.
Article in English | Web of Science | ID: covidwho-20236292

ABSTRACT

Herein, refined LaxCa0.89-xSr0.11MnO3 (LCSMO, x = 0.65, 0.68, 0.71 and 0.74) films were prepared through the sol-gel spin-coating. The influence of La3+ content on the structural properties of LCSMO films was investigated by X-ray diffraction and Atomic force microscope, demonstrating that LCSMO films can grow well on SrTiO3 (00l) substrate. Besides, X-ray photoemission spectroscopy verified the double exchange (DE) effect was weakened with La3+ dopant. The La3+ doping and interconnected grains boundaries (GBs) led to the weakening DE effect and GBs scattering, respectively. Due to superior GBs connectivity, the resistivity of LCSMO films was less than 7.1 x 10(-4) Omega.cm at low temperature of 100 K. Importantly, it is an effective control method to keep the temperature (T-k) corresponding to temperature coefficient of resistivity (TCR) at room temperature with Sr2+ content as constant in LCSMO films. At x = 0.71, the peak TCR value was found to be 8.84%/K and corresponding T-k was 283.15 K. These results are beneficial for advanced application of uncooling infrared bolometer.

4.
American Journal of Gastroenterology ; 117(10 Supplement 2):S361, 2022.
Article in English | EMBASE | ID: covidwho-2327285

ABSTRACT

Introduction: Barrett's esophagus (BE) is a metaplastic change in the distal esophagus in which squamous epithelium is replaced by columnar epithelium with goblet cells. Chronic gastroesophageal reflux disease (GERD) is strongly linked to the development of BE, which is a known precursor lesion to esophageal adenocarcinoma (EAC). There is no universal guideline for BE screening, however AJG suggest a single screening endoscopy in patients with chronic GERD symptoms and 3 or more addition risk factors, such as male sex, age > 50 years, white race, tobacco smoking, obesity and family history of BE or EAC. Within the Veteran's Affair (VA) hospital in Northport, New York, many veterans possess multiple risk factors for BE. Residents in VA primary care clinic are diligent in colorectal cancer screening, yet there is concern for limited offerings for BE screening. Our project aims to study the barriers to BE screening within a high-risk veteran population. Method(s): This is a survey-based study. A total of 36 internal medicine residents working in VA primary care clinic were asked to fill out a survey regarding their perspective towards BE screening. The results of the survey are compiled in Table. Result(s): 36 residents within the clinic completed the survey. As shown in Table, 35 out of 36 residents expressed that the primary care clinic does not screen for BE adequately. 30 residents expressed uncertainty regarding referral criteria for BE screening, 24 residents revealed having never referred patients for BE screening. When asked about barriers regarding BE screening, consensus polling showed that there is a lack of resident education surrounding indications for screening. Other common barriers include lack of transportation for veterans to appointments, the COVID 19 pandemic, and lack of health literacy within the veteran population. Conclusion(s): Although there is no established guideline for BE screening, per AJG there is recommendation for a one-time screening endoscopy in susceptible population. VA patients pose a high-risk population that appears to have low screening rates. Patients appear to be placed on long term PPIs without re-assessment and endoscopic screening despite possessing multiple risk factors for BE. Our survey shows that within our resident cohort there is concern for lack of awareness regarding screening criteria for BE. With the initiation of this project, we hope to increase awareness of BE screening within the resident group and improve health outcomes within veteran population. (Table Presented).

5.
Journal of Risk ; 25(4):83-120, 2023.
Article in English | Scopus | ID: covidwho-2327284

ABSTRACT

We examine the high-frequency intraday return and volatility transmission between crude oil futures prices and exchange rates during the 2020 Covid-19 pandemic in the context of two markets: the newly established renminbi-denominated Shanghai International Energy Exchange in China and the US-dollar-denominated Brent market in the United Kingdom. By controlling for the influence of the stock markets, our findings reveal significant disparities in return linkages, yet fairly comparable volatility transmission patterns. The International Energy Exchange shows no return linkages with exchange rates except before the shock, while Brent consistently shows return spillovers from crude oil futures prices to exchange rates. In both markets, the volatility spillovers from exchange rates to crude oil futures prices are unidirectional prior to the shock but become bidirectional as a result of the shock. Nevertheless, both the return and volatility spillover patterns in China resemble those in the United Kingdom when utilizing offshore instead of onshore exchange rates. Such similarities in return and volatility spillovers can also be observed during the 2022 Covid-19 shock that emerged in Shanghai. These findings have significant practical implications. © Infopro Digital Limited 2023.

6.
Journal of Biological Chemistry ; 299(3 Supplement):S575, 2023.
Article in English | EMBASE | ID: covidwho-2320166

ABSTRACT

Phosphoserine (pSer) sites are primarily located within disordered protein regions, making it difficult to experimentally ascertain their effects on protein structure and function. Therefore, the production of 15N- (and 13C)-labeled proteins with site-specifically encoded pSer for NMR studies is essential to uncover molecular mechanisms of protein regulation by phosphorylation. While genetic code expansion technologies for the translational installation of pSer in Escherichia coli are well established and offer a powerful strategy to produce site-specifically phosphorylated proteins, methodologies to adapt them to minimal or isotope-enriched media have not been described. This shortcoming exists because pSer genetic code expansion expression hosts require the genomic DELTAserB mutation, which increases pSer bioavailability but also imposes serine auxotrophy, preventing growth in minimal media used for isotopic labeling of recombinant proteins. Here, by testing different media supplements, we restored normal BL21(DE3) DELTAserB growth in labeling media but subsequently observed an increase of phosphatase activity and mis-incorporation not typically seen in standard rich media. After rounds of optimization and adaption of a high-density culture protocol, we were able to obtain >=10 mg/L homogenously labeled, phosphorylated superfolder GFP. To demonstrate the utility of this method, we also produced the intrinsically disordered serine/arginine-rich region of the SARS-CoV-2 Nucleocapsid protein labeled with 15N and pSer at the key site S188 and observed the resulting peak shift due to phosphorylation by 2D and 3D heteronuclear single quantum correlation analyses. We propose this cost-effective methodology will pave the way for more routine access to pSer-enriched proteins for 2D and 3D NMR analyses. GCE4All Biomedical Technology Development and Dissemination Center was supported by National Institute of General Medical Science, OSU NMR Facility funded in part by the National Institutes of Health, the Medical Research Foundation at OHSU and the Collins Medical Trust, National Science Foundation EAGER, and by the M. J. Murdock Charitable Trust.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.

7.
Journal of Biological Chemistry ; 299(3 Supplement):S641, 2023.
Article in English | EMBASE | ID: covidwho-2319165

ABSTRACT

The N protein of the SARS-CoV-2 virion is critical for viral genome packaging via RNA binding and regulation of viral transcription at the replication-transcription complex (RTC). The N protein can be divided into five main domains, and the central region is the linker, which is predicted to be primarily disordered and has not been heavily studied. The linker is Serine-Arginine Rich, which is phosphorylated at multiple sites by host kinases during infection, thereby promoting the N protein's role in viral transcription. Phosphorylation is a critical process for the regulation of many cellular processes and can provide recognition sites for binding complexes. In a study that examined the recognition of the SARS-CoV-2 N protein by the human 14-3-3 protein, the linker was found to contain critical phosphosites for 14-3-3 binding. The goals of this project are to determine the structure, dynamics, and RNA interactions of the Serine-Arginine Rich linker region. To accomplish this, we performed Nuclear Magnetic Resonance spectroscopy (NMR) experiments to analyze the structure of the linker region of the N protein and its ability to bind viral RNA. NMR confirms predictions that the linker is not entirely unstructured and it is able to bind RNA. The linker region of the N protein with phosphoserine incorporated at S188 was also examined via an NMR titration experiment with 1-1000 RNA. Compared to wild type, the incorporation of phosphorylation decreases binding. Other biophysical techniques such as Analytical Ultracentrifugation (AUC) and Multi-Angle Light Scattering (MALS) are used to identify the association state of the linker and the size of the resulting protein-RNA complex. We are currently working to biophysically characterize the structure, dynamics, and viral RNA binding ability of a mutation found in the Delta and Omicron variants: the R203M linker, which have been shown to enhance viral infectivity. This work was supported by the NSF EAGER grant NSF/ MCB 2034446 and URSA Engage. Support to facilities includes the Oregon State University NMR Facility funded in part by NIH, HEI Grant 1S10OD018518, and by the M. J. Murdock Charitable Trust grant # 2014162.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.

8.
Land ; 12(3), 2023.
Article in English | Scopus | ID: covidwho-2292805

ABSTRACT

COVID-19 opened a window of opportunity to change the green development of the hospitality industry. For many years, Chinese tourists have been the world's largest source of outbound tourists. Therefore, this study attempted to improve built-environment strategies for green rooms at B&Bs using the empirical statistics of Chinese tourists after the end of COVID-19 control measures and different green B&B standards, combining IPA (importance-performance analysis). For the lack of a green built-environment study from a tourism perspective, this study can be used mainly for improving the green satisfaction of urban B&Bs as it attempted to fill the gaps in research on green B&B rooms. This study will significantly help improve the quality of green rooms for the B&B industry in the future, and it also provides an improved green B&B room sample for other countries and regions. Moreover, it is an optimistic attempt at hospitality and tourism recovery. © 2023 by the authors.

9.
Interactive Technology and Smart Education ; 2023.
Article in English | Scopus | ID: covidwho-2269159

ABSTRACT

Purpose: The application of artificial intelligence chatbots is an emerging trend in educational technology studies for its multi-faceted advantages. However, the existing studies rarely take a perspective of educational technology application to evaluate the application of chatbots to educational contexts. This study aims to bridge the research gap by taking an educational perspective to review the existing literature on artificial intelligence chatbots. Design/methodology/approach: This study combines bibliometric analysis and citation network analysis: a bibliometric analysis through visualization of keyword, authors, organizations and countries and a citation network analysis based on literature clustering. Findings: Educational applications of chatbots are still rising in post-COVID-19 learning environments. Popular research issues on this topic include technological advancements, students' perception of chatbots and effectiveness of chatbots in different educational contexts. Originating from similar technological and theoretical foundations, chatbots are primarily applied to language education, educational services (such as information counseling and automated grading), health-care education and medical training. Diversifying application contexts demonstrate specific purposes for using chatbots in education but are confronted with some common challenges. Multi-faceted factors can influence the effectiveness and acceptance of chatbots in education. This study provides an extended framework to facilitate extending artificial intelligence chatbot applications in education. Research limitations/implications: The authors have to acknowledge that this study is subjected to some limitations. First, the literature search was based on the core collection on Web of Science, which did not include some existing studies. Second, this bibliometric analysis only included studies published in English. Third, due to the limitation in technological expertise, the authors could not comprehensively interpret the implications of some studies reporting technological advancements. However, this study intended to establish its research significance by summarizing and evaluating the effectiveness of artificial intelligence chatbots from an educational perspective. Originality/value: This study identifies the publication trends of artificial intelligence chatbots in educational contexts. It bridges the research gap caused by previous neglection of treating educational contexts as an interconnected whole which can demonstrate its characteristics. It identifies the major application contexts of artificial intelligence chatbots in education and encouraged further extending of applications. It also proposes an extended framework to consider that covers three critical components of technological integration in education when future researchers and instructors apply artificial intelligence chatbots to new educational contexts. © 2023, Emerald Publishing Limited.

10.
International Journal of Online Pedagogy and Course Design ; 12(1), 2022.
Article in English | Scopus | ID: covidwho-2256902

ABSTRACT

With the rapid development of information technologies, virtual reality-Assisted language learning (VRALL) has caught much attention across the world, particularly during the COVID-19 pandemic. Nevertheless, few review studies aimed to understand the influence of virtual reality (VR) on learning outcomes in terms of each language element. This literature review study selected and analyzed 23 studies from the perspective of language learning aspects, main users of VR technology, and the impact of VR on each learning aspect. The results revealed that (1) vocabulary learning and tertiary education gained the most attention in academia;(2) VR promoted pronunciation learning, listening skills, and speaking skills;(3) VR was a mixed blessing for vocabulary learning, reading skills, and writing skills. Future research could explore the solutions to improve the effectiveness of VR and highlight interdisciplinary cooperation. © 2022 IGI Global. All rights reserved.

11.
21st International Symposium on Distributed Computing and Applications for Business Engineering and Science, DCABES 2022 ; : 225-228, 2022.
Article in English | Scopus | ID: covidwho-2288084

ABSTRACT

Several studies have shown that fatigue driving is one of the important causes of public transport safety accidents. With the outbreak of the COVID-19, the wearing of masks by public transport drivers presents new challenges for computer-based visual fatigue detection. In order to achieve the goal of accurately capturing the landmark information of the face even when the face is occluded by a large area, we adopt the DNN-based face detection method which has the highest accuracy and the best occlusion resistance. When the driver's face is blocked, the landmark information of the blocked face can be accurately detected by using our optimized face landmark detector. The accuracy rate of landmark recognition can reach 97.80%. On this basis, we calculate the driver's eye information, mouth information and the driver's head deflection angle information in real time as the judgment indicators of the degree of fatigue to comprehensively evaluate the driver's fatigue state. And use mathematical methods to fuse indicators in real time, classify the driver's fatigue state according to the value of the fusion indicators, and adopt different early warning methods for different levels of fatigue. In addition, in order to further improve the accuracy of the detection results and exclude the influence of other facial behaviors on our fatigue judgment indicators, we propose a kinetic energy calculation formula for facial organs based on the improved optical flow method. According to the different kinetic energy of facial organs in different states, which can accurately distinguish the different behaviors of the same facial organs such as blinking and closing eyes, yawning and speaking, which significantly increases the robustness and generalization ability of the detection program. The final experimental results show that the correct rate of the method for determining the degree of fatigue of the driver and passengers can reach 98.40% and 92.30% respectively when the driver does not wear a mask or wears a mask. © 2022 IEEE.

12.
Chinese Journal of Clinical Infectious Diseases ; 13(3):172-174, 2020.
Article in Chinese | EMBASE | ID: covidwho-2287521
13.
Chinese Journal of Clinical Infectious Diseases ; 13(3):172-174, 2020.
Article in Chinese | EMBASE | ID: covidwho-2287520
14.
Microbiological Research ; 266, 2023.
Article in English | Scopus | ID: covidwho-2242950

ABSTRACT

Bacterial drug resistance has become a global public health threat, among which the infection of carbapenem-resistant Enterobacterales (CRE) is one of the top noticeable issues in the global anti-infection area due to limited therapy options. In recent years, the prevalence of CRE transmission around the world has increased, and the transmission of COVID-19 has intensified the situation to a certain extent. CRE resistance can be induced by carbapenemase, porin, efflux pump, penicillin-binding protein alteration, and biofilm production. Deletion, mutation, insertion, and post-transcriptional modification of corresponding coding genes may affect the sensitivity of Enterobacterales bacteria to carbapenems. Clinical and laboratory methods to detect CRE and explore its resistance mechanisms are being developed. Due to the limited options of antibiotics, the clinical treatment of CRE infection also faces severe challenges. The clinical therapies of CRE include single or combined use of antibiotics, and some new antibiotics and treatment methods are also being developed. Hence, this review summarizes the epidemiology, resistance mechanisms, screening and clinical treatments of CRE infection, to provide references for clinical prevention, control and treatment of CRE infection. © 2022 Elsevier GmbH

15.
International Public Management Journal ; 2022.
Article in English | Web of Science | ID: covidwho-2228481

ABSTRACT

As society faces more crises, it is critical for leaders, especially at the local level, to make decisions and intervene before reaching the tipping point. This often requires collective sensemaking across boundaries, but most studies focus on the challenges. This article asks how decision makers make timely decisions. It presents an institutions-process framework and analyzes the process and mechanism in the case of the response of E-Zhong City-just over an hour's drive from Wuhan City in Hubei Province-to COVID-19 in the "Golden Seven Days" of 2020. Decision makers achieved timely decisions by exploiting all possible political opportunities and institutional tools, maximizing the diversity of the information available, and using multiple discourses and frameworks to enhance personal crisis awareness and achieve collective sensemaking across boundaries. This article defines the mechanism as bricolage and defines these decision makers as institution-knowledge bricoleurs. The concept of institution-knowledge bricoleurs extends the study of crisis decision making and the relationship between institutions and sensemaking.

16.
Galactica Media-Journal of Media Studies - Galaktika Media-Zhurnal Media Issledovanij ; 4(4):30-46, 2022.
Article in English | Web of Science | ID: covidwho-2206506

ABSTRACT

Governments hiding facts and truth from the public seems to have become a common phenomenon, especially during the social crisis in China. The practice of the public using various media to express dissent and opinions, to overcome government censorship, appears to contribute to freedom of speech. Inspired by widespread online articles during the COVID-19 pandemic in 2020, this paper argues that the flaws in this logic are the dualism, which digital media created (pro-democracy vs authoritarian;freedom vs control), in understanding media in China. By borrowing the discussion of the de-westernization of media and communication studies, the paper argues that the introduc-tion of digital media makes de-westernized studies in China harder because it prompts us to think "digitally."

17.
28th ACM SIGSAC Conference on Computer and Communications Security, CCS 2022 ; : 2009-2023, 2022.
Article in English | Scopus | ID: covidwho-2162010

ABSTRACT

As the COVID-19 pandemic fundamentally reshaped the remote life and working styles, Voice over IP (VoIP) telephony and video conferencing have become a primary method of connecting communities together. However, little has been done to understand the feasibility and limitations of delivering adversarial voice samples via such communication channels. In this paper, we propose TAINT-Targeted Adversarial Voice over IP Network, the first targeted, query-efficient, hard label black-box, adversarial attack on commercial speech recognition platforms over VoIP. The unique channel characteristics of VoIP pose significant new challenges, such as signal degradation, random channel noise, frequency selectivity, etc. To address these challenges, we systematically analyze the structure and channel characteristics of VoIP through reverse engineering. A noise-resilient efficient gradient estimation method is then developed to ensure a steady and fast convergence of the adversarial sample generation process. We demonstrate our attack in both over-the-air and over-the-line settings on four commercial automatic speech recognition (ASR) systems over the five most popular VoIP Conferencing Software (VCS). We show that TAINT can achieve performance that is comparable to the existing methods even with the addition of VoIP channel. Even in the most challenging scenario where there is an active speaker in Zoom, TAINT can still succeed within 10 attempts while staying out of the speaker focus of the video conference. © 2022 Owner/Author.

18.
International Journal of Information and Communication Technology Education ; 18(1), 2022.
Article in English | Scopus | ID: covidwho-2144010

ABSTRACT

The use of social media such as Twitter has gained popularity in education during the COVID-19 pandemic. This study included 22 high-quality peer-reviewed journal articles for the meta-analysis. The authors reveal that there are no significant differences in teaching effectiveness between the Twitter and non-Twitter-assisted learning approaches. Twitter-assisted learning outcomes are significantly higher than the non-Twitter-assisted whether Twitter is used as a supplementary or an integrated tool. Twitter-assisted learning can lead to significantly higher learning outcomes than non-Twitter-assisted learning in the USA, Greece, and Sweden, but no significant difference is revealed in Spain. Swedish users hold significantly positive attitudes towards the use of Twitter in education, but no significant difference is found in the USA. Twitter-assisted learning can cause significantly more engagement than non-Twitter-assisted in the USA, and male learners have significantly higher learning outcomes than females in both the USA and Spain. © 2022 Authors. All rights reserved.

19.
International Journal of Online Pedagogy and Course Design ; 12(1), 2022.
Article in English | Web of Science | ID: covidwho-2121933

ABSTRACT

The most popular media of content delivery in online learning and education in the post-pandemic time has been learning management systems (LMS) or virtual learning environments (VLEs). Since few studies comprehensively presented the impact of gamification in the VLEs/LMS (GVLEs/GLMS) on learning outcomes, satisfaction, engagement, and motivation, this review aims to identify the effects of gamification in the contexts of VLEs/LMS. The authors adopted a systematic review method based on the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P). The results showed that the GLMS had positive influences on learning motivation, engagement, and satisfaction while it did not necessarily improve learning outcomes due to various factors. Implications and suggestions were given to researchers, developers, educators, and institutions based on the findings.

20.
23rd International Conference on Electronic Packaging Technology, ICEPT 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2078212

ABSTRACT

Along with the COVID-19 pandemic and the large-scale application of 5G, IoT has become more critical for our daily lives. GaAs is a promising semiconductor for field effect transistors in IoT applications. Due to the high electron mobility of GaAs, n-type FinFET based on GaAs is expected with a higher conductance and electron velocity than Silicon. FinFET based on GaAs has a lower subthreshold swing (SS) and higher Ion/Ioff than FinFET based on Silicon, particularly at high temperatures.Negative Capacitance FinFET(NC-FinFET) is an important emerging technology for low-power applications. To further enhance the performance of the GaAs FinFET, we incorporate Hf0.5Zr0.5O2 films in the gate to achieve Negative Capacitance (NC). The NC effect brings a higher Ion/Ioff and a negative coefficient to reduce the SS of the FinFET. Our simulation research proves the GaAs-NC-FinFET has the slightest SS variation in 300K-400K and maximum Ion/Ioff compared with other FinFETs. © 2022 IEEE.

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