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Research on student engagement has recently gained popularity as it can address problems such as early dropout and poor achievement. The growing interest in investigating student engagement during the Covid-19 pandemic is reflected in increased publications addressing this topic. However, no review provided research evidence and an overview of existing literature on student engagement during emergency remote teaching (ERT). We reviewed how student engagement studies were undertaken during ERT from three perspectives: (1) the landscape of studies, (2) methodologies issues, and (3) the strategies used to facilitate student engagement. 42 articles were analysed from an initial pool of 436 search results. The findings illustrate that current studies were predominately undertaken in the United States (36%) and China (22%) with focusing on STEM subjects as a dominant discipline. The literature was largely inconsistent in defining and measuring student engagement. In addition, the majority of studies (57%) investigated students' engagement from the perspective of students, unlike other stakeholders. The most prominent finding is that ERT promoted several important engagement strategies, including motivational factors, teachers' facilitation, a hybrid learning model, and using learning technologies to boost students' engagement. [ABSTRACT FROM AUTHOR]

The dual-credit policy, implemented by the Chinese government on April 1, 2018, aims at boosting the production of new energy vehicles and further reducing fuel consumption of internal combustion engine vehicles. However, whether the policy is effective has caused controversy among many scholars in China and one of the hot spots of debate is about the effectiveness of the pricing method. In this paper, the government pricing model of dual-credit policy and the market pricing model are compared by the optimization theory. The factors include the transaction price of credits, the quantity of vehicles, the monopoly manufacturer's profits, and social welfare. Our results show that the dual-credit policy benefits energy saving and emission reduction in the transport sector. In addition, it is suggested that the government should formulate the transaction price of credits and subsidy the automobile enterprise in the early stage of the policy while adopting free market pricing in the late stage of the policy. [ABSTRACT FROM AUTHOR]

The flavonoid extract from Erigeron breviscapus, breviscapine, has increasingly been used to treat cardio- and cerebrovascular diseases in China for more than 30 years, and plant supply of E. breviscapus is becoming insufficient to satisfy the growing market demand. Here we report an alternative strategy for the supply of breviscapine by building a yeast cell factory using synthetic biology. We identify two key enzymes in the biosynthetic pathway (flavonoid- 7-O-glucuronosyltransferase and flavone-6-hydroxylase) from E. breviscapus genome and engineer yeast to produce breviscapine from glucose. After metabolic engineering and optimization of fed-batch fermentation, scutellarin and apigenin-7-O-glucuronide, two major active ingredients of breviscapine, reach to 108 and 185 mg l-1, respectively. Our study not only introduces an alternative source of these valuable compounds, but also provides an example of integrating genomics and synthetic biology knowledge for metabolic engineering of natural compounds. [ABSTRACT FROM AUTHOR]

An interhemispheric hydrologic seesaw-in which latitudinal migrations of the Intertropical Convergence Zone (ITCZ) produce simultaneous wetting (increased precipitation) in one hemisphere and drying in the other-has been discovered in some tropical and subtropical regions. For instance, Chinese and Brazilian subtropical speleothem (cave formations such as stalactites and stalagmites) records show opposite trends in time series of oxygen isotopes (a proxy for precipitation variability) at millennial to orbital timescales, suggesting that hydrologic cycles were antiphased in the northerly versus southerly subtropics. This tropical to subtropical hydrologic phenomenon is likely to be an initial and important climatic response to orbital forcing. The impacts of such an interhemispheric hydrologic seesaw on higher-latitude regions and the global climate system, however, are unknown. Here we show that the antiphasing seen in the tropical records is also present in both hemispheres of the mid-latitude western Pacific Ocean. Our results are based on a new 550,000-year record of the growth frequency of speleothems from the Korean peninsula, which we compare to Southern Hemisphere equivalents. The Korean data are discontinuous and derived from 24 separate speleothems, but still allow the identification of periods of peak speleothem growth and, thus, precipitation. The clear hemispheric antiphasing indicates that the sphere of influence of the interhemispheric hydrologic seesaw over the past 550,000 years extended at least to the mid-latitudes, such as northeast Asia, and that orbital-timescale ITCZ shifts can have serious effects on temperate climate systems. Furthermore, our result implies that insolation-driven ITCZ dynamics may provoke water vapour and vegetation feedbacks in northern mid-latitude regions and could have regulated global climate conditions throughout the late Quaternary ice age cycles. [ABSTRACT FROM AUTHOR]

Duane retraction syndrome (DRS) is a neuromuscular dysfunction of the eyes. Although many causative genes of DRS have been identified in Europe and the United States, few reports have been published in regard to Chinese DRS. The aim of the present study was to explore the genetic defect of DRS in a Chinese family. Exome sequencing was used to identify the disease-causing gene for the two affected family members. Ophthalmic and physical examinations, as well as genetic screenings for variants in chimerin 1 (CHN1), were performed for all family members. Functional analyses of a CHN1 variant in 293T cells included a Rac-GTP activation assay, α2-chimaerin translocation assay, and co-immunoprecipitation assay. Genetic analysis revealed a NM_001822.7: c.637T > G variant in the CHN1 gene, which resulted in the substitution of a highly conserved C1 domain with valine at codon 213 (NP_001813.1: p.(Phe213Val)) (ClinVar Accession Number: SCV001335305). In-silico analysis revealed that the p.(Phe213Val) substitution affected the protein stability and connections among the amino acids of CHN1 in terms of its tertiary protein structure. Functional studies indicated that the p.(Phe213Val) substitution reduced Rac-GTP activity and enhanced membrane translocation in response to phorbol-myristoyl acetate (PMA). Together with previous studies, our present findings demonstrate that CHN1 may be an important causative gene for different ethnicities with DRS. [ABSTRACT FROM AUTHOR]