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1.
Transboundary and Emerging Diseases ; 2023, 2023.
Artigo em Inglês | Web of Science | ID: covidwho-20238770

RESUMO

Wild animals are considered reservoirs for emerging and reemerging viruses, such as the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Previous studies have reported that bats and ticks harbored variable important pathogenic viruses, some of which could cause potential diseases in humans and livestock, while viruses carried by reptiles were rarely reported. Our study first conducted snakes' virome analysis to establish effective surveillance of potential transboundary emerging diseases. Consequently, Adenoviridae, Circoviridae, Retroviridae, and Parvoviridae were identified in oral samples from Protobothrops mucrosquamatus, Elaphe dione, and Gloydius angusticeps based on sequence similarity to existing viruses. Picornaviridae and Adenoviridae were also identified in fecal samples of Protobothrops mucrosquamatus. Notably, the iflavirus and foamy virus were first reported in Protobothrops mucrosquamatus, enriching the transboundary viral diversity in snakes. Furthermore, phylogenetic analysis revealed that both the novel-identified viruses showed low genetic similarity with previously reported viruses. This study provided a basis for our understanding of microbiome diversity and the surveillance and prevention of emerging and unknown viruses in snakes.

2.
Research in Transportation Business and Management ; 46, 2023.
Artigo em Inglês | Web of Science | ID: covidwho-2308961

RESUMO

The marine transport companies have been experiencing intense competition with the supply increasing faster than the demand, making most of them face input congestion. This paper applies the input congestion data envelopment analysis (DEA) model proposed by Tone and Sahoo (2004) to compute efficiency scores and input congestions of 159 major marine transport companies in the world during 2010-2019. The inputs include em-ployees, total assets, and capital whereas the output is net sales. The base year for monetary values is 2010. It is found that the annual ratios of input-congested marine companies are between 20.9% and 65.7%, indicating that input congestion is not an unusual phenomenon among these companies. This paper also applies a BCG-like analysis to consider inefficiency and input congestion at the same time. The Mann-Whitney U test shows that most of the marine transport companies in Asia, Europe, and the Americas face both inefficiency and input congestion problems during the data period. This analysis is able to provide the implications for shipping companies to conduct more precise and efficient resource allocation and coordination in the post Covid-19 era.

3.
Journal of Physical Chemistry C ; 2022.
Artigo em Inglês | Web of Science | ID: covidwho-2185480

RESUMO

Semiconducting single-walled carbon nanotubes (SWCNTs) with tailored corona phases (CPs), or surface adsorbed molecules, have emerged as a promising interface for sensing applications. The adsorption of an analyte can be specifically transduced as a modulation of their band-gap near infrared (nIR) photoluminescence (PL). One such CP ideal for this purpose is single-stranded DNA (ssDNA), where subsequent sequence-dependent hybridization can result in PL emission wavelength shifts. Due to ssDNA adsorption to the SWCNT surface, the resultant noncanonical hybridization and its effect on SWCNT photophysical properties are not well understood. In this work, we study 20-and 21-mer DNA and RNA hybridization on the complementary ssDNA-SWCNT CP in the context of nucleic acid sensing for SARS-CoV-2 sequences as model analytes. We found that the van't Hoff transition enthalpy of hybridization on SWCNT CP was -11.9 kJ mol-1, much lower than that of hybridization in solution (-707 kJ mol-1). We used SWCNT solvatochromism to calculate the solvent-exposed surface area to indicate successful hybridization. We found that having a 30-mer anchor region in addition to the complementary region significantly improved PL response sensitivity and selectivity, with a (GT)15 anchor preferred for RNA targets. Coincubation of ssDNA-SWCNTs with an analyte at 37 degrees C resulted in faster hybridization kinetics without sacrificing specificity. Other methods aimed to improve CP rearrangement kinetics such as bath sonication and surfactant additions were ineffective. We also determined that the target sequence choice is important as secondary structure formation in the target is negatively correlated with hybridization. Best performing CPs showed detection limits of 11 and 13 nM for DNA and RNA targets, respectively. Finally, we simulated sensing conditions using the saliva environment, showing sensor compatibility in biofluids. In total, this work elucidates key design features and processing to enable sequence-specific hybridization on ssDNA-SWCNT CPs.

4.
Library Hi Tech ; 2022.
Artigo em Inglês | Scopus | ID: covidwho-1806856

RESUMO

Purpose: This study explored the students' perception of their adoption and acceptance of virtual learning (VL), the factors affecting the adoption of educational technologies and the correlation between their intention, perceived behavioral control and care competence in caring for older adults. Design/methodology/approach: A cross-sectional survey was conducted. Surveys were administered to evaluate the participants who were involved in VL on geriatric care during coronavirus disease 2019 (COVID-19) pandemic. A total of 315 nursing students participated in the survey, and 287 valid questionnaires were collected (response rate: 91.11%). Findings: A total of 287 participants (mean age 21.09, SD 1.44 years;242/287, 84.3% female) were included in the study. The variables of intention to use technologies were positively correlated with care competence (r = 0.59, p < 0.001). The results revealed that the major predictors were perceived ease-of-use (PEOU) (β = 0.28, 95% confidence interval (CI) 0.16–0.40) and perceived usefulness (PU) (β = 0.22, CI 0.09–0.35) which were significantly positive predictors of competence in geriatric care. Research limitations/implications: Nursing students lack in clinical knowledge and situational experience in geriatric care;therefore, their perceptiveness, expressions and reflection on the process of providing care to hospitalized older patients should be increased. These results indicated that students improved in geriatric healthcare after/during the VL program during COVID-19 pandemic. Originality/value: It is hoped that the present study would make an invaluable contribution to existing research on education in general and on the quality of care in geriatric nursing as limited studies have been published so far. © 2022, Pei-Lun Hsieh, Shang-Yu Yang, Wen-Yen Lin and Tien-Chi Huang.

5.
3rd IEEE Eurasia Conference on Biomedical Engineering, Healthcare and Sustainability, ECBIOS 2021 ; : 247-250, 2021.
Artigo em Inglês | Scopus | ID: covidwho-1713987

RESUMO

After the outbreak of COVID-19, traditional offline teaching is not carried out normally. However, education cannot be stopped. In this case, many teachers are facing challenges, not subject to geographical restrictions, diverse ways, and other advantages. Thus, online teaching has become an important teaching method in this special period. Based on the literature review, this paper summarizes the evaluation criteria of different levels of online English teaching. Using the questionnaire survey, experts and scholars were consulted for several rounds. After the validity of the questionnaire by using a fuzzy Delphi method, the evaluation criteria system of English online teaching was established, and the importance, order, and grade of the evaluation criteria were evaluated. This system allows teachers to formulate teaching strategies to optimize and improve English online teaching. The findings of this paper shed some light on efficient learning strategies and ensure the effect of online English teaching. © 2021 ECBIOS 2021. All rights reserved.

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7.
Canadian Journal of Chemical Engineering ; : 12, 2021.
Artigo em Inglês | Web of Science | ID: covidwho-1335991

RESUMO

Recent studies have shown that rutin (Quercetin-3-O-rhamnosylglucoside) may have an inhibitory effect on COVID-19. Rutin can be extracted from Tartary buckwheat as an active pharmaceutical ingredient. Nevertheless, its purification is mainly hindered by Kaempferol-3-O-rutinoside (K3R) due to their similar molecular structures. This study intends to propose a simulated moving bed (SMB) chromatography process of rutin and K3R to achieve continuous production. True moving bed (TMB) and SMB models were established to numerically analyze and optimize this process. The system consists of a four-zone SMB with two columns in each zone. The effects of the switch interval, feed flowrate, desorbent flowrate, extract flowrate, raffinate flowrate, and recycle flowrate on the purity and yield of rutin and K3R were investigated and the optimized conditions were chosen as 5 min, 3.5, 40, 34, 9.5, and 24.5 L/min, respectively. Consequently, the purities of 99.64% and 99.25%, and the yields of 99.81% and 99.37% for rutin and K3R were obtained, respectively. The simulation results can provide a guidance for the future industrial application of SF-SMB to separate rutin and K3R.

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