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This study uses CiteSpace to map the scientometric analysis of dynamic assessment (DA) research in the Web of Science core collection from 1990 to 2022 in the areas of psychology, education and language learning. Firstly, the study found that DA was initially employed in the fields of psychology and special education, and has been gaining attention from second language acquisition researchers in recent years. And Vygotsky, the representative figure of sociolcultural theory, has the highest influence, and Budoff has the greatest degree as a bridge. Secondly, five research topics are found through keyword clustering, which are early identification, group dynamic assessment, short-term progress monitoring, computerized dynamic assessment and teacher education. At the same time, the analysis of burst reference shows that the computerized dynamic assessment will be the trend in the future, and dynamic assessment of second language tends to use mixed research method. Through a review of previous studies, this paper explores the paradigms and methods of empirical research in DA, hoping to provide new alternatives for future research.

In new paradigms, teachers’ cognition and emotion must be considered dialectically shaped co-evolving processes. To address the issue, the study examined how language teachers’ perezhivaniya(plural form of perezhivanie, a concept from Sociocultural Theory that describes a unity between cognition and emotion) developed. During a semester (17 weeks), a study of 13 teachers of Japanese as a foreign language was conducted at a university in northeast China. Narrative inquiry was used to collect perezhivaniya excerpts from retrospective diaries, reflection diaries, and interviews. Q-methodology was also employed to group participants based on their cognitive and emotional changes toward technology-mediated language teaching (TMLT). In our study, teachers’ negative perezhivaniya resulted from a lack of affordances for online and hybrid education in professional development. Teachers experienced many dramas (unit of analysis of perezhivaniya) as they adapted to TMLT. Conversely, teachers’ positive perezhivaniya originated from teacher agency and developed through affordances offered by the sociocultural community. We also found teacher perezhivaniya changed in three staged patterns: resistance and demotivation (during large-scale offline teaching before the pandemic), obligation and adaptation (during large-scale online teaching during the pandemic), and inventiveness and motivation (during online and offline blended teaching after the pandemic). In conclusion, we identified teachers’ perezhivaniya developed in a dynamic, historical, complex as well as multi-layered (with time-developmental, drama-historical, and SSD-social as indicators) pattern.

In response to the problem of inaccurate classification of big data information in traditional English teaching ability evaluation algorithms, this paper proposes an English teaching ability estimation algorithm based on big data fuzzy K-means clustering. Firstly, the article establishes a constraint parameter index analysis model. Secondly, quantitative recursive analysis is used to evaluate the capabilities of big data information models and achieve entropy feature extraction of capability constrained feature information. Finally, by integrating big data information fusion and K-means clustering algorithm, the article achieves clustering and integration of indicator parameters for English teaching ability, prepares corresponding teaching resource allocation plans, and evaluates English teaching ability. The experimental results show that using this method to evaluate English teaching ability has good information fusion analysis ability and improves the accuracy of teaching ability evaluation and the efficiency of teaching resource application.

The zone of proximal development (ZPD) and the scaffolding theory are very different, both in terms of their theoretical origins and connotations, and can even be said to be very different. However, during the development of the two concepts, some scholars have misunderstood them, resulting in the two being mistaken for similar concepts and therefore often confused. Professor James Lantolf from Pennsylvania State University (State College, USA) was interviewed by Professor Lili Qin from Dalian University of Foreign Studies (Dalian, China) and provides an in-depth analysis of these issues. The interview begins with the theoretical roots, connotations and definitions of the ZPD and scaffolding concepts, and then unravels the story of how they have been “mistakenly loved for life”, and ultimately it is made clear that the two concepts are completely different in their practical application to language teaching and should not continue to be used interchangeably.

Omicron (B.1.1.529), the most heavily mutated SARS-CoV-2 variant so far, is highly resistant to neutralizing antibodies, raising concerns about the effectiveness of antibody therapies and vaccines1,2. Here we examined whether sera from individuals who received two or three doses of inactivated SARS-CoV-2 vaccine could neutralize authentic Omicron. The seroconversion rates of neutralizing antibodies were 3.3% (2 out of 60) and 95% (57 out of 60) for individuals who had received 2 and 3 doses of vaccine, respectively. For recipients of three vaccine doses, the geometric mean neutralization antibody titre for Omicron was 16.5-fold lower than for the ancestral virus (254). We isolated 323 human monoclonal antibodies derived from memory B cells in triple vaccinees, half of which recognized the receptor-binding domain, and showed that a subset (24 out of 163) potently neutralized all SARS-CoV-2 variants of concern, including Omicron. Therapeutic treatments with representative broadly neutralizing monoclonal antibodies were highly protective against infection of mice with SARS-CoV-2 Beta (B.1.351) and Omicron. Atomic structures of the Omicron spike protein in complex with three classes of antibodies that were active against all five variants of concern defined the binding and neutralizing determinants and revealed a key antibody escape site, G446S, that confers greater resistance to a class of antibodies that bind on the right shoulder of the receptor-binding domain by altering local conformation at the binding interface. Our results rationalize the use of three-dose immunization regimens and suggest that the fundamental epitopes revealed by these broadly ultrapotent antibodies are rational targets for a universal sarbecovirus vaccine.

Preceding works tend to explicate affordance through supposing what is happening here and now. They seldom relate it to actual social, diachronic activities, such as foreign language learning. To tackle this issue, this study explores how students actualize affordances in technology-enriched language learning environment (TELLE) by examining their perezhivanija (lived and emotional experience), a term borrowed from sociocultural theory. Because an individual’s social life is a developing process or a perezhivaniePerezhivanieis the singular form of perezhivanija., it is necessary to base the research in a dynamic development of language learning to figure out how the affordances are actualized. Narrative interviews were adopted to collect data from three Chinese college students who learn English as a foreign language in a Northeastern university in China. The results showed that due to the students’ different past perezhivanija in English learning, their present interpretations of the perceived affordances in TELLE varied. This influenced hugely in their actions taken during their English learning in college to actualize the affordances. The findings indicated that the actualization of affordances is historical, dynamic and developmental instead of static. It does not lie in the autonomy of the students or the teachers, but in the institutional and cultural legitimacy of technology use in student’s social life. The paper contributes to the application of affordance theory in foreign language learning and provides implications to language teaching practice in TELLE.

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Circulating tumor cells (CTCs) have emerged as promising circulating biomarkers for non-invasive cancer diagnosis and management. Isolation and detection of CTCs in clinical samples are challenging due to the extreme rarity and high heterogeneity of CTCs. Here, we describe a poly(ethylene oxide) (PEO) concentration gradient-based microfluidic method for rapid, label-free, highly efficient isolation of CTCs directly from whole blood samples. Stable concentration gradients of PEO were formed within the microchannel by co-injecting the side fluid (blood sample spiked with 0.025% PEO) and center fluid (0.075% PEO solution). The competition between the elastic lift force and the inertial lift force enabled size-based separation of large CTCs and small blood cells based on their distinct migration patterns. The microfluidic device could process 1 mL of blood sample in 30 min, with a separation efficiency of >90% and an enrichment ratio of >700 for tumor cells. The isolated CTCs from blood samples were enumerated by immunofluorescence staining, allowing for discrimination of breast cancer patients from healthy donors with an accuracy of 84.2%. The concentration gradient-based microfluidic separation provides a powerful tool for label-free isolation of CTCs for a wide range of clinical applications.

Nuclear DNA repair capacity is a critical determinant of cell fate under genotoxic stress conditions. DNA repair is a well-defined energy-consuming process. However, it is unclear how DNA repair is fueled and whether mitochondrial energy production contributes to nuclear DNA repair. Here, we report a dynamic enhancement of oxygen consumption and mitochondrial ATP generation in irradiated normal cells, paralleled with increased mitochondrial relocation of the cell-cycle kinase CDK1 and nuclear DNA repair. The basal and radiation-induced mitochondrial ATP generation is reduced significantly in cells harboring CDK1 phosphorylation-deficient mutant complex I subunits. Similarly, mitochondrial ATP generation and nuclear DNA repair are also compromised severely in cells harboring mitochondrially targeted, kinase-deficient CDK1. These results demonstrate a mechanism governing the communication between mitochondria and the nucleus by which CDK1 boosts mitochondrial bioenergetics to meet the increased cellular fuel demand for DNA repair and cell survival under genotoxic stress conditions.

Polyurethane acrylates (PUAs) modified by different amounts of stearyl alcohol were synthesized from stearyl alcohol (SA), isophorone diisocyanate, 2-hydroxyethyl acrylate, and polycaprolactone triol. The molecular structure was characterized by Fourier transform infrared spectroscopy. Real time infrared spectroscopy was used to investigate the kinetics of photopolymerization of synthesized PUAs. The volume shrinkage was measured by laser displacement sensor. The adhesion on glass, polycarbonate (PC), and polyvinyl chloride (PVC) was tested by the laser micrometer and universal testing machine. The glass transition temperature (Tg) and storage modulus (E′) were measured by dynamic mechanical analyzer (DMA). The pendulum hardness, pencil hardness and flexibility were also measured. The results showed that the greater the amount of SA in synthesized PUAs, the lower the volume shrinkage and the better the adhesion to glass, PC, and PVC substrates.