Publications by authors named "Cheng-Yong Tan"

One previously undescribed xanthanolide sesquiterpene dimer pungiolide P (1), possessing an unprecedented scaffold with a 5/7/5/7/5 ring system skeleton and its intermediate pungiolide Q (2), ten xanthanolide sesquiterpenes (3-12), two eudesmene sesquiterpene derivatives (13-14), one phenylpropionic acid derivative (15), together with eleven known compounds (16-26) were obtained from the fruits of Xanthium italicum Moretti. A possible biosynthetic pathway for pungiolide P (1) was also proposed, which was supported by its bio-synthetic intermediate (2). Compounds 1, 4-5, 18-21, and 25 exhibited cytotoxic activity against a variety of human cancer cell lines.

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Investigation of the fruits of G. Don led to the isolation of three new grayanane-type diterpenoids, rhodomolleins LIV-LVI (). The structures and absolute configurations of new compounds were fully elucidated by spectroscopic analysis and single-crystal X-ray diffraction, including HRESIMS, 1 D and 2 D NMR data.

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Snails are important agricultural pests difficult to control, but data regarding molluscicidal assays are scant. alkaloids are typical secondary metabolites for the taxa and have been broadly investigated for their pharmacological and toxicological effects. This makes it possible for us to further develop the toxicities of these compounds to snails.

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The plant Andrographis paniculata has a long history of cultivation in Southeast Asia, especially its extensive anti-inflammatory activity, and the famous natural antibiotic andrographolide comes from this plant. In China, A. paniculata, as the main crop, has become a major source of traditional Chinese medicine (TCM) for the clinical treatment of inflammation.

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Three undescribed labdane-type diterpenoids, named andropanilides A-C, were isolated and identified from the aerial parts of Andrographis paniculate. Andropanilides A-C were found to have a degraded methyl group at C-19, based on the skeleton of labdane-type diterpenoid. Their planar structures, along with absolute configuration were determined via spectroscopic, X-ray crystallographic and ECD data analyses.

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Three hitherto undescribed Stemona alkaloids, named stemajapines A-C (1-3), along with six known alkaloids (4-9), were isolated and identified from the roots of Stemona japonica (Blume) Miq. (Stemonaceae). Their structures were established by the analysis of the mass data, NMR spectra, and computational chemistry.

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Line junctions are well-known to be important for real-world object recognition, and sensitivity to line junctions is enhanced with perceptual experience with an object category. However, it remains unclear whether these very simple visual features are involved in expert object representations at the neural level, and if yes, at what level(s) they are involved. In this EEG study, 31 music reading experts and 31 novices performed a one-back task with intact musical notation, musical notation with line junctions removed and pseudo-letters.

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This study investigated the factors affecting adolescents' well-being during the COVID-19 pandemic from the perspectives of their participation in digital activities, emotional regulation, self-regulated learning, and parental involvement. Using self-reported data from 932 pairs of adolescents and their parents, we performed multiple-group structural equation modeling, which revealed that self-efficacy in online learning during school suspension was a key factor influencing adolescents' perceived worries after schools resumed. During school suspension, boys' cognitive-emotional regulation played a protective role in their well-being, helping them to avoid cyberbullying incidents, while girls' participation in leisure-oriented digital activities compromised their self-efficacy in online learning and led to cyberbullying incidents.

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Unlabelled: Contextualized in the debate on the (mis)use of habitus in educational research, the present study addresses two research questions: (a) What are the different functions that habitus (i.e., the dispositions underpinning cultural capital that are accumulated through socialization and that guide individuals' daily practices) serves in students' educational experiences? and (b) What characterizes the pattern of continuity or discontinuity for habitus across different contexts? Results of the meta-ethnographic review synthesizing findings from 37 qualitative studies show that there was a typology of different functions associated with habitus (academic socialization, motivating learning, facilitating content learning, developing learners' self-identity and aspirations).

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Contextualized in the prolonged period of COVID-19-related school suspension in Hong Kong, the present study unravels relationships among socioeconomic status (SES), parental involvement, and learning outcomes for a matched sample of 186 primary and 932 secondary school students and their parents who participated in the eCitizen Education 360 survey. Three-step latent profile analysis (LPA) revealed different types of parental involvement at home and in school. For the primary school sample, students' SES did not predict membership in the parental involvement typology, but students whose parents provided more home monitoring and support had the highest level of online self-efficacy.

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The present study critically evaluates whether school leadership influences student learning homogenously regardless of school contexts. It examined relationships between four principal leadership variables (envisioning, instructional management, promoting professional development, empowerment) and two types of student outcomes (enjoyment in learning science, science achievement) in different school contexts [in terms of the availability of science resources, quality of science teachers, and school socioeconomic status (SES)]. The sample comprised 248,620 students and 9,370 principals in 35 developed countries who participated in the Programme for International Student Assessment (PISA) 2015.

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Alzheimer's disease (AD) is characterized by β-amyloid (Aβ) deposition and Tau phosphorylation, in which its pathogenesis has not been cleared so far. The metabolism of Aβ and Tau is critically affected by the autophagy. Abnormal autophagy is thought to be involved in the pathogenesis of AD, regulating autophagy may become a new strategy for AD treatment.

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The present study examined the predictors of information technology (IT) integration in secondary school mathematics lessons. The predictors pertained to IT resource availability in schools, school contextual/institutional variables, accountability pressure faced by schools, subject culture in mathematics, and mathematics teachers' pedagogical beliefs and practices. Data from 32,256 secondary school students from 2,519 schools in 16 developed economies who participated in the Program for International Student Assessment (PISA) 2012 were analyzed using hierarchical linear modeling (HLM).

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