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1.
J Med Virol ; 96(5): e29664, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38727137

RESUMEN

The causative agent of coronavirus disease 2019 (COVID-19), known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread accumulatively to 240 countries and continues to evolve. To gain a comprehensive understanding of the epidemiological characteristics of imported variants in China and their correlation with global circulating variants, genomic surveillance data from 11 139 imported COVID-19 cases submitted by Chinese provincial CDC laboratories between 2021 and 2022 were analyzed. Consensus sequences underwent rigorous quality checks, followed by amino acid mutations analysis using Nextclade. Sequences with satisfactory quality control status were classified according to the Pango nomenclature. The results showed that the dominant variants in imported cases reflected the global epidemic trend. An increase in the number of imported SARS-CoV-2 lineages monitored in China in the second half of 2022, and the circulating Omicron subvariants changed from the ancestral lineages of BA.5 and BA.2 into the lineages containing key amino acid mutations of spike protein. There was significant variation in the detection of Omicron subvariants among continents (χ2 = 321.968, p < 0.001) in the second half of 2022, with four lineages (BA.2.3.7, BA.2.2, BA.5.2.7, and XBB.1.2) identified through imported surveillance mainly prevalent respectively in Taiwan, China, Hong Kong SAR, China, Russian Federation, and Singapore. These findings revealed the alterations in circulating imported variants from 2021 to 2022 in China, reflecting the higher diversity of lineages in the second half of 2022, and revealed the predominant lineages of countries or regions that are in close contacts to China, providing new insights into the global prevalence of SARS-CoV-2.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , China/epidemiología , COVID-19/epidemiología , COVID-19/virología , SARS-CoV-2/genética , SARS-CoV-2/clasificación , Prevalencia , Glicoproteína de la Espiga del Coronavirus/genética , Filogenia , Mutación , Genoma Viral/genética , Variación Genética
2.
Sensors (Basel) ; 24(11)2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38894383

RESUMEN

Because of the absence of visual perception, visually impaired individuals encounter various difficulties in their daily lives. This paper proposes a visual aid system designed specifically for visually impaired individuals, aiming to assist and guide them in grasping target objects within a tabletop environment. The system employs a visual perception module that incorporates a semantic visual SLAM algorithm, achieved through the fusion of ORB-SLAM2 and YOLO V5s, enabling the construction of a semantic map of the environment. In the human-machine cooperation module, a depth camera is integrated into a wearable device worn on the hand, while a vibration array feedback device conveys directional information of the target to visually impaired individuals for tactile interaction. To enhance the system's versatility, a Dobot Magician manipulator is also employed to aid visually impaired individuals in grasping tasks. The performance of the semantic visual SLAM algorithm in terms of localization and semantic mapping was thoroughly tested. Additionally, several experiments were conducted to simulate visually impaired individuals' interactions in grasping target objects, effectively verifying the feasibility and effectiveness of the proposed system. Overall, this system demonstrates its capability to assist and guide visually impaired individuals in perceiving and acquiring target objects.


Asunto(s)
Algoritmos , Personas con Daño Visual , Dispositivos Electrónicos Vestibles , Humanos , Personas con Daño Visual/rehabilitación , Fuerza de la Mano/fisiología , Dispositivos de Autoayuda , Percepción Visual/fisiología , Semántica , Masculino
3.
Nanotechnology ; 34(45)2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37524070

RESUMEN

The development of low cost efficient catalysts for oxygen evolution reaction (OER) is still a obstacle to realize the commercialization of electrocatalytic water splitting. Herein, interface engineering and heteroatom doping is adopted to synthesize iron and vanadium doped nickel sulfide on nickel foam via hydrothermal method followed by hydrogen treatment to create sulfur defects. The optimized nanoflower-like FeVNi3S2-x/NF is an efficient OER electrocatalyst that outperforms many of the reported transition metals catalysts. Benefiting from abundant sulfur defects and the synergistic effect of heteroatom doping, FeVNi3S2-x/NF exhibits an ultralow overpotential of 230 mV to reach a current density of 100 mA cm-2, a rapid reaction kinetics with a small Tafel slope of 46.6 mV dec-1, and a stable long-term durability in 1 M KOH. Experimental results and characterizations confirm that sulfur vacancies together with the synergistic effect from multiple heteroatom doping can effectively regulate the electronic structure, resulting in increased electrical conductivity and electrochemically active surface area, thus enhancing OER performance. Furthermore,in situRaman spectroscopy reveals that, the reconstitution amorphous nickel oxyhydroxide (NiOOH) on the catalyst surface is responsible for catalyzing the OER reaction. This work represents a promising methodology to synthesize low-cost and highly active OER electrocatalysts.

4.
Acta Cardiol Sin ; 39(6): 783-806, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38022422

RESUMEN

Cardiac rehabilitation is a comprehensive intervention recommended in international and Taiwanese guidelines for patients with acute myocardial infarction. Evidence supports that cardiac rehabilitation improves the health-related quality of life, enhances exercise capacity, reduces readmission rates, and promotes survival in patients with cardiovascular disease. The cardiac rehabilitation team is comprehensive and multidisciplinary. The inpatient, outpatient, and maintenance phases are included in cardiac rehabilitation. All patients admitted with acute myocardial infarction should be referred to the rehabilitation department as soon as clinically feasible. Pre-exercise evaluation, including exercise testing, helps physicians identify the risks of cardiac rehabilitation and organize appropriate exercise prescriptions. Therefore, the Taiwan Myocardial Infarction Society (TAMIS), Taiwan Society of Cardiology (TSOC), and Taiwan Academy of Cardiovascular and Pulmonary Rehabilitation (TACVPR) address this consensus statement to assist healthcare practitioners in performing cardiac rehabilitation in patients with acute myocardial infarction.

5.
Nanotechnology ; 33(48)2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-35921793

RESUMEN

Non-precious and stable electrocatalysts towards both oxygen and hydrogen evolution reaction (OER/HER) are essential for effective overall water splitting in alkaline solution. In this study, a sulfur defective and manganese-doped nickel sulfide nanosheet that uniformly grown on nickel foam substrate (Mn-Ni3S2-x@NF) is synthesized. In alkaline solution, the Mn-Ni3S2-x@NF showed a low overpotential of 76 and 110 mV for OER and HER at 10 mA cm-2, respectively, together exhibiting excellent stability for both OER and HER reaction. It was confirmed by the experimental results that sulfur defects and Mn-doping synergistically optimized the electronic structure of Mn-Ni3S2-xwith increased electrical conductivity and enhanced OER/HER activity. Moreover, amorphous nickel oxyhydroxide (NiOOH) was observed byin situRaman during the OER condition, suggesting NiOOH is the active phase for OER reaction. Furthermore, the electrolyzer assembled by Mn-Ni3S2-x@NF merely needs 1.46 V to reach 10 mA cm-2and shows good stability as well. This study provides a feasible way to prepare high-efficiency bifunctional catalysts for overall water splitting.

6.
Nanotechnology ; 33(48)2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35994980

RESUMEN

Lithium-sulfur (Li-S) battery is now a promising technology for energy storage. However, rapid capacity decay due to sulfur dissolution and shutting effect severely limit its commercial development. In this work, a NH2-UIO-66 metal organic framework-derived porous composite (Co-ZrO2@NC) consists of nitrogen-doped carbon (NC) and zirconium oxide (ZrO2) loaded with cobalt nanoparticles was prepared. The porous NC component not only increases the accommodation of sulfur in the cathode, but also benefits the charge transfer in sulfur electrochemistry. The Co and ZrO2would act as active centers to enhance the adsorption/conversion of lithium polysulfide and improve its electrochemical utilization. When used in sulfur cathode, the Co-ZrO2@NC electrode shows excellent electrochemical performance with an initial specific capacity of 1073 mAh g-1at a rate of 0.2 C and a reversible capacity of 1015 mAh g-1after 100 cycles, corresponding to a capacity retention of 94.6%. Furthermore, after 300 cycles at 1.0 C, corresponding to a capacity retention of 75.4%. Moreover, the cell also exhibits good rate performance (640 mAh g-1at 3.0 C). Even at high sulfur loading of 4.0 mg cm-2, the S/Co-ZrO2@NC cathode is able to deliver an areal specific capacity of 4.8 mAh cm-2.

7.
Mol Biol Evol ; 35(1): 132-148, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29048557

RESUMEN

The adenosine-to-inosine (A-to-I) RNA editomes have been systematically characterized in various metazoan species, and many editing sites were found in clusters. However, it remains unclear whether the clustered editing sites tend to be linked in the same RNA molecules or not. By adopting a method originally designed to detect linkage disequilibrium of DNA mutations, we examined the editomes of ten metazoan species and detected extensive linkage of editing in Drosophila and cephalopods. The prevalent linkages of editing in these two clades, many of which are conserved between closely related species and might be associated with the adaptive proteomic recoding, are maintained by natural selection at the cost of genome evolution. Nevertheless, in worms and humans, we only detected modest proportions of linked editing events, the majority of which were not conserved. Furthermore, the linkage of editing in coding regions of worms and humans might be overall deleterious, which drives the evolution of DNA sites to escape promiscuous editing. Altogether, our results suggest that the linkage landscape of A-to-I editing has evolved during metazoan evolution. This present study also suggests that linkage of editing should be considered in elucidating the functional consequences of RNA editing.


Asunto(s)
Adenosina/genética , Inosina/genética , Edición de ARN/genética , Adaptación Fisiológica/genética , Adenosina/metabolismo , Animales , Cefalópodos/genética , Drosophila/genética , Evolución Molecular , Ligamiento Genético/genética , Genoma/genética , Humanos , Inosina/metabolismo , Desequilibrio de Ligamiento/genética , Ratones , Sistemas de Lectura Abierta/genética , Filogenia , Proteómica/métodos , ARN/genética , Selección Genética/genética
8.
J Am Chem Soc ; 139(19): 6530-6533, 2017 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-28460166

RESUMEN

We show that an enzyme maintains its biological function under a wider range of conditions after being embedded in metal-organic framework (MOF) microcrystals via a de novo approach. This enhanced stability arises from confinement of the enzyme molecules in the mesoporous cavities in the MOFs, which reduces the structural mobility of enzyme molecules. We embedded catalase (CAT) into zeolitic imidazolate frameworks (ZIF-90 and ZIF-8), and then exposed both embedded CAT and free CAT to a denature reagent (i.e., urea) and high temperatures (i.e., 80 °C). The embedded CAT maintains its biological function in the decomposition of hydrogen peroxide even when exposed to 6 M urea and 80 °C, with apparent rate constants kobs (s-1) of 1.30 × 10-3 and 1.05 × 10-3, respectively, while free CAT shows undetectable activity. A fluorescence spectroscopy study shows that the structural conformation of the embedded CAT changes less under these denaturing conditions than free CAT.


Asunto(s)
Catalasa/química , Imidazoles/farmacología , Estructuras Metalorgánicas/farmacología , Desplegamiento Proteico/efectos de los fármacos , Zeolitas/farmacología , Catalasa/metabolismo , Imidazoles/química , Estructuras Metalorgánicas/química , Tamaño de la Partícula , Porosidad/efectos de los fármacos , Conformación Proteica/efectos de los fármacos , Espectrometría de Fluorescencia , Propiedades de Superficie/efectos de los fármacos , Temperatura , Zeolitas/química
9.
J Am Chem Soc ; 137(13): 4276-9, 2015 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-25781479

RESUMEN

We develop a new concept to impart new functions to biocatalysts by combining enzymes and metal-organic frameworks (MOFs). The proof-of-concept design is demonstrated by embedding catalase molecules into uniformly sized ZIF-90 crystals via a de novo approach. We have carried out electron microscopy, X-ray diffraction, nitrogen sorption, electrophoresis, thermogravimetric analysis, and confocal microscopy to confirm that the ~10 nm catalase molecules are embedded in 2 µm single-crystalline ZIF-90 crystals with ~5 wt % loading. Because catalase is immobilized and sheltered by the ZIF-90 crystals, the composites show activity in hydrogen peroxide degradation even in the presence of protease proteinase K.


Asunto(s)
Biocatálisis , Catalasa/química , Catalasa/metabolismo , Nanoporos , Compuestos Organometálicos/química , Tamaño de la Partícula , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Peróxido de Hidrógeno/metabolismo , Imidazoles/química , Cinética , Modelos Moleculares , Conformación Proteica , Zeolitas/química
10.
Micromachines (Basel) ; 15(6)2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38930663

RESUMEN

Virtual reality technology brings a new experience to human-computer interaction, while wearable force feedback devices can enhance the immersion of users in interaction. This paper proposes a wearable fingertip force feedback device that uses a tendon drive mechanism, with the aim of simulating the stiffness characteristics of objects within virtual scenes. The device adjusts the rotation angle of the torsion spring through a DC motor, and then uses a wire to convert the torque into a feedback force at the user's index fingertips, with an output force of up to 4 N and a force change rate of up to 10 N/s. This paper introduces the mechanical structure and design process of the force feedback device, and conducts a mechanical analysis of the device to select the appropriate components. Physical and psychological experiments are conducted to comprehensively evaluate the device's performance in conveying object stiffness information. The results show that the device can simulate different stiffness characteristics of objects, and users can distinguish objects with different stiffness characteristics well when wearing the force feedback device and interacting with the three-dimensional virtual environments.

11.
Biology (Basel) ; 13(6)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38927264

RESUMEN

Padina minor is a seaweed rich in polysaccharides often used in food, feed, fertilizers, and antibacterial drugs. This study is the first to evaluate the effect of feeding zebrafish with Padina minor extract on preventing and treating C. albicans infections. This study evaluated the growth, survival, and disease resistance effects of P. minor extract on zebrafish. The fish were divided into four groups: three groups treated with 1%, 5%, or 10% P. minor extract and one untreated group (c, control). Subsequently, we analyzed how the extract affected the immune function of zebrafish infected with C. albicans. Based on the lethal concentration (LC50) calculated in the first stage, 1% was used as the effective therapeutic concentration. The results showed that the growth rate of the 1% feed group was the best, and no significant difference in survival rates between the four groups was observed. Feeding with 1% P. minor extract downregulated the expression of key inflammatory genes like tumor necrosis factor-alpha (TNF-α), interleukin-1ß (IL-1ß), and IL-10, effectively preventing and treating C. albicans infections in zebrafish. This study is a preliminary evaluation of the therapeutic efficacy of P. minor extracts against C. albicans.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38862422

RESUMEN

The monkeypox virus (mpox virus, MPXV) epidemic in 2022 has posed a significant public health risk. Yet, the evolutionary principles of MPXV remain largely unknown. Here, we examined the evolutionary patterns of protein sequences and codon usage in MPXV. We first demonstrated the signal of positive selection in OPG027, specifically in the Clade I lineage of MPXV. Subsequently, we discovered accelerated protein sequence evolution over time in the variants responsible for the 2022 outbreak. Furthermore, we showed strong epistasis between amino acid substitutions located in different genes. The codon adaptation index (CAI) analysis revealed that MPXV genes tended to use more non-preferred codons compared to human genes, and the CAI decreased over time and diverged between clades, with Clade I > IIa and IIb-A > IIb-B. While the decrease in fatality rate among the three groups aligned with the CAI pattern, it remains unclear whether this correlation was coincidental or if the deoptimization of codon usage in MPXV led to a reduction in fatality rates. This study sheds new light on the mechanisms that govern the evolution of MPXV in human populations.


Asunto(s)
Uso de Codones , Evolución Molecular , Monkeypox virus , Humanos , Monkeypox virus/genética , Proteínas Virales/genética , Filogenia , Selección Genética , Codón/genética , Secuencia de Aminoácidos/genética , Sustitución de Aminoácidos/genética , Mpox/virología , Mpox/genética
13.
China CDC Wkly ; 6(15): 324-331, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38736991

RESUMEN

Introduction: In the first half of 2023, a global shift was observed towards the predominance of XBB variants. China faced a significant epidemic between late 2022 and early 2023 due to Omicron subvariants BA.5.2 and BF.7. This study aims to depict the evolving variant distribution among provincial-level administrative divisions (PLADs) in China and explore the factors driving the predominance of XBB replacement. Methods: Sequences from local and imported coronavirus disease 2019 (COVID-19) cases recorded between January 1 and June 30, 2023, were included. The study analyzed the changing distribution of viral variants and assessed how the prior dominance of specific variants, XBB subvariants, and imported cases influenced the prevalence of the XBB replacement variant. Results: A total of 56,486 sequences were obtained from local cases, and 8,669 sequences were from imported cases. Starting in April, there was a shift in the prevalence of XBB from imported to local cases, with varying dominance among PLADs. In PLADs previously high in BF.7, the rise of XBB was delayed. A positive correlation was found between XBB proportions in imported cases from January to March and local cases in April. The distribution pattern of XBB subvariants differed between local and imported cases within the same PLAD. No significant differences were noted in the replacement rates of XBB subvariants. Conclusions: The timing of XBB dominance differed among various PLADs in China in the first half of 2023, correlating closely with the prevalence of XBB variants among imported cases.

14.
Virol Sin ; 39(1): 134-143, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38070873

RESUMEN

The monkeypox virus (MPXV) has triggered a current outbreak globally. Genome sequencing of MPXV and rapid tracing of genetic variants will benefit disease diagnosis and control. It is a significant challenge but necessary to optimize the strategy and application of rapid full-length genome identification and to track variations of MPXV in clinical specimens with low viral loads, as it is one of the DNA viruses with the largest genome and the most AT-biased, and has a significant number of tandem repeats. Here we evaluated the performance of metagenomic and amplicon sequencing techniques, and three sequencing platforms in MPXV genome sequencing based on multiple clinical specimens of five mpox cases in Chinese mainland. We rapidly identified the full-length genome of MPXV with the assembly of accurate tandem repeats in multiple clinical specimens. Amplicon sequencing enables cost-effective and rapid sequencing of clinical specimens to obtain high-quality MPXV genomes. Third-generation sequencing facilitates the assembly of the terminal tandem repeat regions in the monkeypox virus genome and corrects a common misassembly in published sequences. Besides, several intra-host single nucleotide variations were identified in the first imported mpox case. This study offers an evaluation of various strategies aimed at identifying the complete genome of MPXV in clinical specimens. The findings of this study will significantly enhance the surveillance of MPXV.


Asunto(s)
Monkeypox virus , Mpox , Humanos , Monkeypox virus/genética , Mpox/diagnóstico
15.
J Colloid Interface Sci ; 651: 27-35, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37536257

RESUMEN

The development of highly active and durable nonprecious metal-based bifunctional electrocatalysts for oxygen reduction/evolution reaction (ORR/OER) is important for rechargeable zinc-air batteries. Herein, a three-dimensional conductive niobium-doped TiO-TiO2 heterostructure supported ZIF-67-derived Co-NC bifunctional catalyst was fabricated. In the Co-NC@Nb-TiOx catalyst, the Nb doping promoted the formation of TiO-TiO2 heterojunction support, enhanced its conductivity and stability and provided strong electron metal-support interaction between Co-NC and Nb-TiOx. Also, the supported Co-NC nanoparticles provided abundant active sites with excellent ORR/OER activity. Experimental analysis reveals that the high OER activity of Co-NC@Nb-TiOx can be attributed to the in-situ generated CoOOH species. It exhibits excellent ORR activity, as shown by its onset potential (0.95 V vs. RHE) and half-wave potential (0.86 V vs. RHE). Its OER overpotential at 10 mA cm-2 is 480 mV. The zinc-air battery realizes outstanding cycling stability over 225 h cycles tested at 10 mA cm-2. This work demonstrates the importance of designing highly stable metal oxide-supported catalysts in electrochemical energy conversion devices.

16.
Signal Transduct Target Ther ; 8(1): 458, 2023 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-38148355

RESUMEN

In 2022, a global outbreak of Mpox (formerly monkeypox) occurred in various countries across Europe and America and rapidly spread to more than 100 countries and regions. The World Health Organization declared the outbreak to be a public health emergency of international concern due to the rapid spread of the Mpox virus. Consequently, nations intensified their efforts to explore treatment strategies aimed at combating the infection and its dissemination. Nevertheless, the available therapeutic options for Mpox virus infection remain limited. So far, only a few numbers of antiviral compounds have been approved by regulatory authorities. Given the high mutability of the Mpox virus, certain mutant strains have shown resistance to existing pharmaceutical interventions. This highlights the urgent need to develop novel antiviral drugs that can combat both drug resistance and the potential threat of bioterrorism. Currently, there is a lack of comprehensive literature on the pathophysiology and treatment of Mpox. To address this issue, we conducted a review covering the physiological and pathological processes of Mpox infection, summarizing the latest progress of anti-Mpox drugs. Our analysis encompasses approved drugs currently employed in clinical settings, as well as newly identified small-molecule compounds and antibody drugs displaying potential antiviral efficacy against Mpox. Furthermore, we have gained valuable insights from the process of Mpox drug development, including strategies for repurposing drugs, the discovery of drug targets driven by artificial intelligence, and preclinical drug development. The purpose of this review is to provide readers with a comprehensive overview of the current knowledge on Mpox.


Asunto(s)
Inteligencia Artificial , Mpox , Humanos , Mpox/tratamiento farmacológico , Mpox/epidemiología , Mpox/prevención & control , Anticuerpos , Brotes de Enfermedades , Antivirales/farmacología , Antivirales/uso terapéutico
17.
China CDC Wkly ; 5(26): 584-591, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37457851

RESUMEN

Introduction: Since 2019, numerous variants of concern for severe acute respiratory syndrome virus 2 (SARS-CoV-2) have emerged, leading to significant outbreaks. The development of novel, highly accurate, and rapid detection techniques for these new SARS-CoV-2 variants remains a primary focus in the ongoing efforts to control and prevent the coronavirus disease 2019 (COVID-19) pandemic. Methods: Reverse transcription-recombinase polymerase amplification combined with the clustered regularly interspaced short palindromic repeats-associated protein 12a (CRISPR/Cas12a) system was used to validate the detection of the Omicron BA.2, BA.4, and BA.5 variants of SARS-CoV-2. Results: Our results demonstrate that the CRISPR/Cas12a assay is capable of effectively detecting the SARS-CoV-2 BA.2, BA.4, and BA.5 variants with a limit of detection of 10, 1, and 10 copies/µL, respectively. Importantly, our assay successfully differentiated the three SARS-CoV-2 Omicron strains from one another. Additionally, we evaluated 46 SARS-CoV-2 positive clinical samples consisting of BA.2 (n=20), BA.4 (n=6), and BA.5 (n=20) variants, and the sensitivity of our assay ranged from 90% to 100%, while the specificity was 100%. Discussion: This research presents a swift and reliable CRISPR-based method that may be employed to track the emergence of novel SARS-CoV-2 variants.

18.
China CDC Wkly ; 5(7): 143-151, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-37009519

RESUMEN

Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has generated 2,431 variants over the course of its global transmission over the past 3 years. To better evaluate the genomic variation of SARS-CoV-2 before and after the optimization of coronavirus disease 2019 (COVID-19) prevention and control strategies, we analyzed the genetic evolution branch composition and genomic variation of SARS-CoV-2 in both domestic and imported cases in China (the data from Hong Kong and Macau Special Administrative Regions and Taiwan, China were not included) from September 26, 2022 to January 29, 2023. Methods: Analysis of the number of genome sequences, sampling time, dynamic changes of evolutionary branches, origin, and clinical typing of SARS-CoV-2 variants submitted by 31 provincial-level administrative divisions (PLADs) and Xinjiang Production and Construction Corps (XPCC) was conducted to assess the accuracy and timeliness of SARS-CoV-2 variant surveillance. Results: From September 26, 2022 to January 29, 2023, 20,013 valid genome sequences of domestic cases were reported in China, with 72 evolutionary branches. Additionally, 1,978 valid genome sequences of imported cases were reported, with 169 evolutionary branches. The prevalence of the Omicron variants of SARS-CoV-2 in both domestic and imported cases was consistent with that of international epidemic variants. Conclusions: This study provides an overview of the prevalence of Omicron variants of SARS-CoV-2 in China. After optimizing COVID-19 prevention and control strategies, no novel Omicron variants of SARS-CoV-2 with altered biological characteristics or public health significance have been identified since December 1, 2022.

19.
Front Psychol ; 13: 1028722, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36467207

RESUMEN

Introduction: Teacher support is an important external factor that influences students academic self-efficacy, however, the mechanisms of the two factors are not yet fully explored. The purpose of this study was to investigate whether achievement goals and academic emotions could play a chain mediating role between perceived teacher support and academic self-efficacy. Methods: The study sample was made up of 1,074 Chinese junior high school students, and three structural equation models were constructed using data collected from on questionnaires. Results: The findings suggest that achievement goals and academic emotions can mediate the relationship between perceived teacher support and academic selfefficacy. Further analysis revealed that achievement goals and academic emotions may play a chain mediating role between perceived teacher support and academic selfefficacy. Discussion: These findings provide reference points for further refinement of the mechanism of the role of perceived teacher support on academic self-efficacy. They also serve to remind the teacher on the front line to focus on how to provide adequate teacher support to students in the context of online education, especially with regard to students academic emotions.

20.
Front Psychol ; 13: 1066164, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36578684

RESUMEN

Introduction: The instructional video is considered to be one of the most distinct and effective virtual learning tools. However, one of its biggest drawbacks is the lack of social interaction that occurs. This study tested the impact of participants sending zero danmaku (sending messages on the screen), three danmaku sending, and unlimited danmaku as an instructional video plays on learning performance. Methods: We assessed learners' retention and transfer scores, as well as self-report scores for cognitive load and parasocial interaction. This study sample comprised 104 participants who were randomly assigned to learn from one of three instructional videos on the topic of the heart. Results: The results showed that sending danmaku improved learners' parasocial interaction, while significantly increasing their cognitive load and also hindering learning performance. The observed increase in cognitive load reported by learners was also caused by increased levels of parasocial interaction. Discussion: Our findings suggest that by sending danmaku, learners can promote interactive learning, but that this has a negative impact on learning performance and the process of video learning.

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