Search

The Nature of Science (NOS) is an important component of scientific literacy. Science teachers' Views of the Nature of Science (VNOS) directly affect their teaching behaviors. Therefore, it is of great significance to explore science teachers' VNOS and find ways of improvement. This study was designed to comparatively investigate preservice science teachers' VNOS between China and Canada. The study employed a survey design to explore how Chinese and Canadian preservice science teachers understood the seven different aspects of NOS. Data showed that preservice science teachers in China and Canada both hold a modern view about science education. The level of Chinese and Canadian participants' understanding of NOS was above the relatively naive level. Chinese teachers had better macro-understanding toward science education, but their micro-mastery was insufficient. The Canadian participants had a better understanding of the NOS than their Chinese counterparts. The study suggested that there is a need to reconstruct the preservice science teacher education curriculum in China and promote the transformation in the science teacher educational system.

Purpose: The Canadian university where this study took place has established an international exchange program in teacher education with a large Chinese university. This study was designed to examine how the international exchange program influenced Chinese science teacher candidates' understanding of science education and how such learning impacted their teaching in China. Design/Approach/Methods: The study adopted a qualitative research design with interview and reflective journal as the main approaches for data collection. Findings: Participants greatly appreciated the opportunity of exchange. They reported an improved understanding of Canadian school education and its science curriculum and pedagogy, which changed many aspects of their original values about the relationship between the teacher and students, classroom environment, and so on. Although they faced many constraints to implement what they learned from the exchange in Chinese science classrooms, what they learned had never been forgotten. Participants tried to apply them here and there at the level they could control. Originality/Value: There are many reported studies in the literature about Chinese international students on Western campuses. However, research on Chinese students who participate in international exchange programs is very rare. The findings of this study can inform policymakers and education practitioners about student international exchange programs and benefit future exchange participants.

Silicon photonics with the advantages of low power consumption and low fabrication cost is a crucial technology for facilitating high-capacity optical communications and interconnects. The graphene photodetectors (GPDs) featuring broadband operation, high speed, and low integration cost can be good additions to the SiGe photodetectors, supporting high-speed photodetection in wavelength bands beyond 1.6 μm on silicon. Here we realize a silicon-integrated four-channel wavelength division multiplexing (WDM) optical receiver based on a micro-ring resonator (MRR) array and four p-n homojunction GPDs. These photo-thermoelectric (PTE) GPDs exhibit zero-bias responsivities of ∼1.1 V W−1 and set-up limited 3 dB-bandwidth >67 GHz. The GPDs show good consistence benefiting from the compact active region array (0.006 mm2) covered by a single mechanically exfoliated hBN/graphene/hBN stack. Moreover, the WDM graphene optical receiver realized 4 × 16 Gbps non-return-to-zero optical signal transmission. To the best of our knowledge, it is the first GPD-array-based optical receiver using high-quality mechanically exfoliated graphene and edge graphene-metal contacts with low resistances. Apparently, our design is also compatible with CVD-grown graphene. This work sheds light on the large-scale integration of GPDs with high consistency and uniformity, enabling the application of high-quality mechanically exfoliated graphene, and promoting the development of the graphene photonic integrated circuits.

The 24 Nature Notes project was part of the China-Canada Reciprocal Learning Program. Two sister schools participated in the project. Following the same set of dates, students from both schools conducted outdoor observations and collected data. Skype meetings were arranged to exchange ideas and share student work. This study aims to understand the impact of the project on Canadian and Chinese teachers and students, what they learned from each other, and what challenges they faced. Data was collected through observation notes, meeting minutes, student work, and interviews with both Chinese and Canadian teachers and students. Data analysis revealed that the project was a positive opportunity for participants from both countries to gain cross-cultural understanding. The Canadian students enjoyed the freedom in topic selection and presentation formats. They particularly liked the life lessons that the Chinese students shared through their work. The Canadian teachers also valued the idea as it allows students to reflect their observations from a different context. The Chinese teachers and students appreciated the Canadian students' creativity. They gained inspiration from Canadian teachers and students and as a return their project work became more creative.

As part of the SSHRC partnership grant on Reciprocal Learning between Ontario, Canada and Southwest, China, we examined the commonalities and differences in secondary school Inquiry-based Teaching (IBT) in science between sister schools in Ontario, Canada and Southwest, China. Canadian and Chinese teachers' interpretations of inquiry through video-recorded lessons, qualitative observational annotations, and quantitative data collected via the EQUIP instrument were analyzed. Results suggest that there is a non-significant difference in application of IBT between secondary science teachers in Ontario, Canada and in Southwest, China between the reciprocal learning populations. Both populations are perceived to use inquiry-based teaching methods in their classrooms proficiently, and that students are more receptive at a higher cognitive level when teachers incorporate IBT.

Mid-infrared (MIR) silicon photonics have attracted great interest for potential applications in on-chip spectroscopy, free-space communication, and remote imaging. Currently, the high-performance and fabrication-friendly fiber-to-chip grating couplers operating at 3–4 μm wavelength band are still desired urgently. Here, we propose an efficient method for designing a 2D subwavelength grating coupler. The few analytical fitting parameters defining the subwavelength grating periods and fill factors in two dimensions enable a high design degree of freedom and a low search space dimension, resulting in high figure-of-merit and fast convergence simultaneously. The developed 3.7 μm grating coupler showcases record-high coupling efficiency both theoretically (−2.2 dB) and experimentally (−4.4 dB) among the 3–4 μm MIR counterparts. This study provides an effective method for designing fiber-to-chip grating couplers, by which the MIR grating couplers with high performance and fabrication ease are developed, thus paving the way for developing high-performance silicon photonic integrated circuits operating in the MIR wavelength band. [ABSTRACT FROM AUTHOR]

Hydrogel scaffolds have numerous potential applications in the tissue engineering field. However, tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties. Inspired by Chinese ramen, we propose a universal fabricating method (printing-P, training-T, cross-linking-C, PTC & PCT) for tough hydrogel scaffolds to fill this gap. First, 3D printing fabricates a hydrogel scaffold with desired structures (P). Then, the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance (T). Finally, the training results are fixed by photo-cross-linking processing (C). The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa (622-fold untreated) and have excellent biocompatibility. Furthermore, this scaffold possesses functional surface structures from nanometer to micron to millimeter, which can efficiently induce directional cell growth. Interestingly, this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt, and many hydrogels, such as gelatin and silk, could be improved with PTC or PCT strategies. Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers, blood vessels, and nerves within 4 weeks, prompting the rapid regeneration of large-volume muscle loss injuries., (© 2024. The Author(s).)

Paeonia lutea is a wild peony (an endangered flowering plant species) found in China. Seed abortion (endosperm and embryo development failure) is linked to several endangered plant species. Therefore, it is of interest to complete a comparative analysis of transcriptome between the normal active seeds (Population A) and the endangered abortion seeds (Population H). Data from GO assignments of differentially expressed genes (DEGs) shows that "metabolic process", "binding", "cellular process", "catalytic activity", "cell" and "cell part" are commonly prevalent in these popuations. DEGs between the populations are found to be connected with metabolic pathways, biosynthesis of secondary metabolites, purine metabolism and ribosome. We used quantitative RT-PCR to validate 16 DEGs associated with these populations. It is found that histone genes and proline-rich extensin genes are predominant in the common groups. Histone genes (H2A, H2B, H3, H4 and linker histone H1) show 3 to 4 folds log2FC higher expession in population A than in population H in stage I unlike in stage II and III. Increased activity of proline-rich extensin genes in population A than in population H corresponding to seed abortion in the later population is implied. These preliminary data from the transcriptome analysis of the wild type plant species Paeonia lutea provide valuable insights on seed abortion., (© 2020 Biomedical Informatics.)