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Qualitative content analysis is used in this study to review related online education since the outbreak of COVID-19. The aim of this study was to summarize the impact of online teaching on the education industry during the pandemic, sum up the viewpoints of all kinds of people to draw conclusions, and conclude the practical countermeasures. Based on the result of the analysis, firstly, we think that students and teachers are satisfied with online education, but parents have expressed dissatisfaction with this kind of education. Secondly, this paper lists the advantages and common problems of online teaching during study at home from different aspects. According to deficits, we summarize the solutions from three aspects: network equipment, teaching, and self-adjustment. This research is of great significance. It is not only beneficial to the development of educational platforms and personalized teaching but also helps formulate education policy to reduce the burden of education.

Abstract Elucidating cellular architecture and cell-type evolution across species is central to understanding immune system function and susceptibility to disease. Adaptive immunity is a shared trait of the common ancestor of cartilaginous and bony fishes. However, evolutionary features of lymphocytes in these two jawed vertebrates remain unclear. Here, we present a single-cell RNA sequencing atlas of immune cells from cartilaginous (white-spotted bamboo shark) and bony (zebrafish and Chinese tongue sole) fishes. Cross-species comparisons show that the same cell types across different species exhibit similar transcriptional profiles. In the bamboo shark, we identify a phagocytic B cell population expressing several pattern recognition receptors, as well as a T cell sub-cluster co-expressing both T and B cell markers. In contrast to a division by function in the bony fishes, we show close linkage and poor functional specialization among lymphocytes in the cartilaginous fish. Our cross-species single-cell comparison presents a resource for uncovering the origin and evolution of the gnathostome immune system.

This study aimed to assess the neurotoxic effects of the novel psychoactive substance 4-hydroxy-N-methyl-N-isopropyltryptamine (4-HO-MiPT) on brain. By employing zebrafish as a model organism, the study applied a multifaceted approach, including the recording and analysis of spontaneous behavioral activities, identification of brain metabolic products via ultra-high performance liquid chromatography coupled with quadrupole-Orbitrap high resolution mass spectrometry (UHPLC-Q/Orbitrap HRMS), and examination of changes in the transcriptional level of target genes. Following the injection of 4-HO-MiPT, zebrafish exhibites a pronounced reduction in movement speed and range, indicating a significant alteration in locomotor activity. The subsequent analysis of brain metabolic products finds 37 differential metabolites, including 7 elevated and 30 reduced ones, alongside notable alterations in 6 metabolic pathways. Moreover, the examination of transcriptional level of key genes in zebrafish brain underscores a discernible decrease in transcriptional level of genes associated with the nervous system, implying a substantial impact on neuronal function and synaptic transmission. The experimental findings substantiate the neurotoxic effects of 4-HO-MiPT on the zebrafish brain, shedding light on its deleterious repercussions on both the nervous and immune systems. Furthermore, the perturbations observed in metabolic processes and behavioral responses emphasize the profound impact of 4-HO-MiPT exposure on fundamental physiological functions. The identification of potential carcinogenicity associated with 4-HO-MiPT further underscores the urgent need for comprehensive risk assessment and regulatory scrutiny. This study represents a crucial step towards unraveling the intricate neurotoxic mechanisms underlying 4-HO-MiPT exposure. The research has far-reaching implications, not only in advancing our understanding of the adverse health effects associated with novel psychoactive substances, but also in guiding the development of targeted interventions and regulatory strategies aiming at safeguarding public health and well-being. Continued exploration into the long-term consequences of 4-HO-MiPT exposure, alongside comprehensive toxicological evaluations, holds promise in mitigating its potential hazards and ensuring the safety of individuals and communities exposed to this emerging threat.

AimTo evaluate the safety and efficacy of posterior scleral application (a modified technique) of an antimetabolite mitomycin C-soaked sponge in trabeculectomy for patients with glaucoma.MethodsThis retrospective study included 101 patients (115 eyes) with glaucoma (aged 12-83y) who underwent trabeculectomy using a modified mitomycin C-soaked sponge placement method. A piece of 3.5×10 mm2 sponge was placed vertically and posteriorly with the long side perpendicular to the limbus. The mitomycin C concentration and exposure time were 0.2-0.5 mg/mL and 1-5min, respectively. Intraocular pressure, best-corrected visual acuity, and hypotensive medications were recorded at baseline and at the final visit. Complications, interventions required, and bleb morphology were recorded postoperatively. The primary outcome was trabeculectomy safety, including complications and bleb morphology; the secondary outcome was the trabeculectomy success rate.ResultsAt the final follow-up [median 28mo, range 7-67mo and interquartile range (IQR) 13mo], the qualified (cumulative) success rate was 93.0% and the complete success rate was 60.0%. No bleb-related complications were observed. The mean height, extent, and vascularity grades were 0.6±0.9, 1.1±0.4, and 2.4±0.9, respectively. All Seidel tests were negative. The mean posteriority grade was 0.8±0.4.ConclusionTrabeculectomy with the long side of a mitomycin C-soaked sponge placed perpendicular to the corneal limbus is safe and effective.

The impact-echo (IE) method is effective for evaluating invisible defects. However, it might return misleading results when its signals are invalid. This challenge aggravates when the tests are conducted using robotic devices that automatically collect massive data. This study proposes an automatic method to eliminate invalid signals based on the ResNet model. First, the signals are visualized into two-dimensional images as the input for ResNet. The input data can then be classified into valid and invalid data via the ResNet model, which is trained with 11,290 signals and tested with 5664 signals. Finally, defects can be detected using the dominant frequencies of the valid-class data. A case study with IE data from two concrete bridges was employed to validate the feasibility of the proposed approach. The results indicate that the method can achieve an average accuracy of 90.6% for eliminating invalid signals and significantly improve the IE test accuracy.

Novel Psychoactive Substances (NPS) derived from tryptamines has been detected in aquatic environments, leading to environmental toxicology concerns. However, the specific toxicological mechanism, underlying these NPS, remains unclear. In our previous work, we used 5-Methoxy-N-isopropyl-N-methyltryptamine (5-MeO-MiPT) as the representative drug for NPS, and found that, 5-MeO-MiPT led to obvious behavioral inhibition and oxidative stress responses in zebrafishes model. In this study, Zebrafish were injected with varying concentrations of 5-MeO-MiPT for 30 days. RNA-seq, qPCR, metabolomics, and histopathological analyses were conducted to assess gene expression and tissue integrity. This study confirms that 5-MeO-MiPT substantially influences the transcription and expression of 13 selected genes, including ucp1, pet100, grik3, and grik4, mediated by the Gαq/11-PLCβ signaling pathway. We elucidate the molecular mechanism that 5-MeO-MiPT can inhibit DAG-Ca2+/Pkc/Erk, Pkc/Pla2/PLCs and Ca2+/Camk Ⅱ/NMDA, while enhance Ca2+/Creb. Those secondary signaling pathways may be the mechanisms mediating 5-MeO-MiPT inhibiting normal behavior in zebrafish. These findings offer novel insights into the toxicological effects and addiction mechanisms of 5-MeO-MiPT. Moreover, it presents promising avenues for investigating other tryptamine-based NPS and offers a new direction for diagnosing and treating liver-brain pathway-related diseases.

In prokaryotes, translation can occur on mRNA that is being transcribed in a process called coupling. How the ribosome affects the RNA polymerase (RNAP) during coupling is not well understood. Here, we reconstituted the E. coli coupling system and demonstrated that the ribosome can prevent pausing and termination of RNAP and double the overall transcription rate at the expense of fidelity. Moreover, we monitored single RNAPs coupled to ribosomes and show that coupling increases the pause-free velocity of the polymerase and that a mechanical assisting force is sufficient to explain the majority of the effects of coupling. Also, by cryo-EM, we observed that RNAPs with a terminal mismatch adopt a backtracked conformation, while a coupled ribosome allosterically induces these polymerases toward a catalytically active anti-swiveled state. Finally, we demonstrate that prolonged RNAP pausing is detrimental to cell viability, which could be prevented by polymerase reactivation through a coupled ribosome.

ABSTRACTWind tunnel tests or computational fluid dynamics (CFD) simulations of the aeroelastic model of a bridge deck section are currently used to make sure that significant vortex-induced vibration (VIV) of a long-span bridge will not occur after the bridge is put into operation. However, significant VIV still occurred in several long-span bridges in operation, indicating that the currently used wind tunnel tests and CFD simulations have some drawbacks or uncertainties. This study aims at establishing a digital twin by interacting CFD simulation with wind tunnel test for accurately and efficiently predicting the VIV response of a bridge deck. The measurement information of VIV of the deck section is collected from the wind tunnel test and fused with the CFD simulation. The optimisation for reducing uncertainties existing in wind tunnel test and CFD simulation is then carried out to make the CFD simulation as a digital twin. The digital twin is finally used to investigate the blockage effect of wind tunnel test and give an accurate and efficient prediction of VIV of the bridge deck. The flat closed-box steel deck section used in the Xiangshan Harbor cable-stayed bridge is selected as a case study. The results from the case study show that the digital twin can be established and used for an accurate and efficient prediction of VIV of the bridge deck section.

In this study, to examine status compensation effect we explore an intriguing behavioral pattern of grant applicants. We draw from the status compensation hypothesis and examine the influence of an applicant's status (i.e. ranking of the applicant's affiliated institution) on the title length of the applicant's grant proposal. In addition, we explore the moderating effects of project discipline, the applicant's grant approval experience, and funding amount. Information of all projects funded by the Management Science Division of the National Natural Science Foundation of China (NSFC) between 2015 and 2019 were screened and analyzed with a pooled cross-section data model. Ranking of the applicant's institution was found to negatively predict the title length of the grant proposal. This effect is more pronounced in grants in Business Administration, for applicants with more experience in grant approval, and when a project has a larger funding amount. Findings of this study illustrate the prevalent status-induced compensatory behaviors in grant applications, which contribute to research on the compensation effect and bear practical implications for the scientific community.

Senecavirus A (SVA) is an important emerging swine pathogen that causes vesicular lesions in swine and acute death in newborn piglets. VP2 plays a significant role in the production of antibodies, which can be used in development of diagnostic tools and vaccines. Herein, the aim of the current study was to identify B-cell epitopes (BCEs) of SVA for generation of epitope-based SVA marker vaccine. Three monoclonal antibodies (mAbs), named 2E4, 1B8, and 2C7, against the SVA VP2 protein were obtained, and two novel linear BCEs, 177SLGTYYR183 and 266SPYFNGL272, were identified by peptide scanning. The epitope 177SLGTYYR183 was recognized by the mAb 1B8 and was fully exposed on the VP2 surface, and alanine scanning analysis revealed that it contained a high continuity of key amino acids. Importantly, we confirmed that 177SLGTYYR183 locates on “the puff” region within the VP2 EF loop, and contains three key amino acid residues involved in receptor binding. Moreover, a single mutation, Y182A, blocked the interaction of the mutant virus with the mAb 1B8, indicating that this mutation is the pivotal point for antibody recognition. In summary, the BCEs that identified in this study could be used to develop diagnostic tools and an epitope-based SVA marker vaccine.