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The aim of this study was to develop an instrument to measure upper-level Chinese elementary students’ attitudes towards science by addressing problems with existing ones, as highlighted in the lit...

Crosscutting concepts (CCCs) are superordinate in the scientific concept system, common across disciplines, and very abstract. These characteristics, with the addition of incoherence in their curricular presentation, can challenge instructors. We designed a modular course based on coherence and conceptual understanding. The course structure was arranged in accordance with intra- and inter-unit coherence of CCCs, and each lesson was prepared according to “concept-based instruction” and the “5E instructional model.” The results of the pretest and posttest and the semi-structured interviews consistently showed that the participating high school students significantly improved their understanding of CCCs, thus supporting the effectiveness of the modular course.

Sustainable, environment-friendly phosphors produced from cheap and readily available precursor materials using green preparation processes are in high demand for lighting applications. Herein, a composite phosphor comprising carbon dots (CDs) and graphitic carbon nitride (g-C3N4) is prepared on a large scale from citric acid and urea in water, through a green microwave assisted in situ heating method. An optimized CDs@g-C3N4 composite with a 1 wt% loading of CDs shows a strong green emission under 410 nm excitation, with a photoluminescence quantum yield of 62% in the solid state. Using this composite as a phosphor in the color conversion layer, a white light emitting diode with a power efficiency of up to 42 lm W−1 is fabricated.

Along the line of offering surface modification strategies to tune emission properties of carbon dots (CDs), a co-crystallization strategy with cyanuric acid (CA) was developed to modulate the bandgap emissions of CDs and produce highly emissive solid composite CD-based materials. The original blue emission of the CDs changed to a green emission of the CDs@CA crystals, which showed a high photoluminescence quantum yield of 62% and room temperature phosphorescence. The CA molecules firmly bonded to the surface of the CDs and cannot be disrupted by polar solvents or temperature stimuli under ambient conditions, which influenced electron transitions of CDs leading to improved luminescence with excellent thermal stability both in solution and solid states.

A lesson plan is a design problem for a teacher. The desired solution to this problem is to design an instructional process that can guide students in constructing an understanding of scientific concepts through their own thinking. This article demonstrates a practical approach to designing an effective lesson plan. The approach has five phases: listing the concepts in a lesson, proposing questions that can be answered by each concept, sequencing the questions according to the logic of student cognitive development, selecting resources and designing tasks to create learning situations, and applying knowledge to scientific research and real life. A meiosis lesson from a high school biology course serves as an example for understanding the solutions to problems that may arise in each phase.

As a new type of luminescent material, carbon dots (CDs) have attracted increased attention for their superior optical properties in recent years. However, CDs generally suffer from aggregation-ind...

Since inquiry was first introduced to science education, a lot of inquiry-based tasks have appeared in textbooks for supporting an inquiry-based approach. These tasks have great potential to direct...

Aggregation-induced luminescence quenching of carbon nanodots (CDs) is the main obstacle for their applications in solid-state light emitting devices. Herein, we developed a one-step synthesis of solid-state emissive CDs with surface aluminum-based polymerization by adding AlCl3 in citric acid and urea via a microwave-heating dehydration process. Due to the strong coordination ability of Al ions with N and O atoms, considerable steric hindrance of Al-based cross-linked polymerization was introduced on the surface of the CDs, which not only avoided aggregation of the green emissive carbon cores but also facilitated efficient energy transfer from the blue emissive polymerized surface to the green emissive carbon cores in aggregates, leading to enhanced green emissions with a photoluminescence quantum yield (PLQY) of 72.7% in the solid state.

Cancer immunotherapy based on carbon-quantum-dots (CQDs) has proven effective. The CQDs composited cancer cell (CM-cancer) exhibit robust customized immunogenicity, which can recruit macrophages and dendritic cells to effectively deliver the cancer antigens into lymph nodes to activate CD8+ T cells, and eventually leads to an anti-cancer immune response all over the body. The CM-cancer is not only able to inhibit primary tumors, but also clearly eliminate metastatic tumors. Our research demonstrates a promising personalized cancer immunotheraputic technology for potential clinical applications.

Cancer immunotherapy based on carbon-quantum-dot (CQD) modified cancer cells (CM-cancer) has proven effective. The CQDs non-distinctively modify the conformational structure of proteins by hydrogen bonding between the protein chains and the permeated CQDs via a thermal treatment. CM-cancer vaccines exhibit robust immunogenicity, which can recruit macrophages and dendritic cells to effectively deliver the cancer antigens into lymph nodes to activate CD8+ T cells, and eventually leads to an anti-cancer immune response all over the body. The CM-cancer vaccinations are not only able to inhibit primary tumors, but also clearly eliminate metastatic tumors. Our research demonstrates a promising personalized cancer immunotheraputic technology for potential clinical applications.

In this work, we report a successful extension of the family of light-emitting colloidal carbon nanostructures to a number of different shapes and morphologies, namely, carbon nanorolls (CNRs) and carbon nanobelts (CNBs). Near infrared (NIR)-emissive CNRs were synthesized via a solvothermal fusion of carbon dots (CDs) triggered by a dehydration process of their surface functional groups. They appear in a form of short cylinders, with diameters ranging from 20 to 40 nm and cylinder lengths ranging from 7 to 20 nm. In ethanol solution, CNRs have a maximum absorption peak at 665 nm and a NIR emission band extending from 650 to 800 nm, with a photoluminescence quantum yield of 9.2%. Intriguingly, the rolled structure of CNRs can be uncoiled under 655 nm laser irradiation (power density 1 W·cm-2) of their solution in ethanol, forming CNBs with a width of 7-20 nm and lengths reaching several hundreds of nanometers, which is accompanied by a considerably decreased absorption band at 665 nm and a decreased NIR emission. This unfolding is ascribed to the decrease of the strength of interlayer hydrogen bonding, owing to the photothermally induced dehydration and further carbonization of the CNRs. Alongside the decreased NIR emission, CNBs exhibit enhanced green and red emissions under UV and green light excitation, respectively, which allows us to demonstrate multiple-level luminescence encryptions on a paper stamped with CNR- and CNB-inks.

Participating in effective professional development (PD) activities is crucial for helping teachers improve the quality of pedagogy and students’ learning results. Numerous factors influence the design of effective PD, one of which is duration. However, many teachers do not find much time to participate in long-term concentrated and continuous PD due to their heavy workloads. Based on this consideration, this paper presents the Workshop-Seminar-Demonstration Class PD (WSD-PD) model, which addresses the factor of duration by shortening the hours of contact, lengthening the total span of time required, and integrating elements such as active learning and expert follow-up to improve teachers’ practical teaching methods. With “Teaching for Conceptual Change” as the theme and junior high school science teachers as participants, the results of the study show that WSD-PD can serve teachers by generating willingness to improve teaching practices for and influence teaching behaviors in them. The settings of different activities in this model are also considered to play distinct and indispensable roles in the program.

This article describes the development and validation of an instrument that can be used for content analysis of inquiry-based tasks. According to the theories of educational evaluation and qualitie...

Phosphorescence processes in composite systems based on luminescent carbon dots (CDs) are of great fundamental and practical interest. Herein, the control of the phosphorescent signal in a CD/polyvinyl alcohol (PVA) composite is realized. Enhanced green phosphorescence is obtained via thermal annealing of the composite under 200 °C, which can be quenched via water treatment, and then recovered again, via either repeated annealing or near-infrared laser irradiation. Water molecules infiltrating the CD/PVA composite lead to considerable vibrational motions of the CD surface groups through destruction of the rigid composite structure together with an increase in the possibility of the penetration of the phosphorescence quenchers, and thus a decrease in the phosphorescence intensity. After repeated annealing, the nonradiative transitions are restricted, and the phosphorescence signal is recovered again. Based on such on–off switching of the phosphorescence signal, a concept of multiple data encryption is realized by using the CD@PVA composite.

Although understandings of scientific inquiry (as opposed to conducting inquiry) are included in science education reform documents around the world, little is known about what students have learned about inquiry during their elementary school years. This is partially due to the lack of any assessment instrument to measure understandings about scientific inquiry. However, a valid and reliable assessment has recently been developed and published, Views About Scientific Inquiry (VASI; Lederman et al. [2014], Journal of Research in Science Teaching, 51, 65–83). The purpose of this large-scale international project was to collect the first baseline data on what beginning middle school students have learned about scientific inquiry during their elementary school years. Eighteen countries/regions spanning six continents including 2,634 students participated in the study. The participating countries/regions were: Australia, Brazil, Chile, Egypt, England, Finland, France, Germany, Israel, Mainland China, New Zealand, Nigeria, South Africa, Spain, Sweden, Taiwan, Turkey, and the United States. In many countries, science is not formally taught until middle school, which is the rationale for choosing seventh grade students for this investigation. This baseline data will simultaneously provide information on what, if anything, students learn about inquiry in elementary school, as well as their beginning knowledge as they enter secondary school. It is important to note that collecting data from all of the approximately 200 countries globally was not humanly possible, and it was also not possible to collect data from every region of each country. The results overwhelmingly show that students around the world at the beginning of grade seven have very little understandings about scientific inquiry. Some countries do show reasonable understandings in certain aspects but the overall picture of understandings of scientific inquiry is not what is hoped for after completing 6 years of elementary education in any country.

We designed a course based on inquiry learning using WISE, an online inquiry-based science environment platform, and the 5E instructional model. This article summarizes guidelines used in designing the course, analyses of student needs and school environment, setting of course objectives, modification of materials, and evaluation of student performance. A “Healthy Life” course based on those guidelines was implemented, along with a teacher-training workshop, in two schools, and pretests and posttests were administered to evaluate the achievements of the project participants. The results showed that the participants had constructed scientific concepts and improved their level of cognitive knowledge. An efficiency questionnaire and semistructured interviews demonstrated the effectiveness of the course, thus indicating that we should share the guidelines and features of the Healthy Life course with other course designers and teachers.

The purpose of this article was to present an overview of pre-service science teacher preparation in China, which is heavily influenced by Chinese tradition, Confucianism, and rapid social and economic development. The policies, science teacher education systems and related programs jointly contribute to producing enough science teachers for hundreds of thousands of schools at different levels. At the same time, some important reforms should be undertaken, and more candidates with the ability to do educational research should be trained. These qualified science teachers not only face the challenges of the new round of science education reform, but also take opportunities to implement new science curriculum effectively. Therefore, it will facilitate professional development and improve science education in turn.

In the context of the new round of science education reform, a substantial number of teacher professional learning communities have been established in mainland China to apply the beliefs and goals of the new science curriculum standards to a broad set of classroom teaching practices. These professional learning communities adopted a standards-based, pedagogical content knowledge (PCK) perspective and offered teachers the opportunities for self- and collegial reflection. In this chapter, we unpack the typical preservice science teacher preparation programs and four representative in-service science teacher professional development models in mainland China: online teacher education programs, model lesson study, workshops for distinguished teachers, and collective lesson preparation. The examples described in this chapter show preservice science teachers’ development provided by certain approved institutions, which focus primarily on the development of scientific and educational knowledge and teaching practices. These examples also show when individuals graduate from these institutions and become in-service science teachers at K-12 schools, they will gain further development by adopting a standards-based, PCK perspective and engaging in self- and collegial reflection through professional learning communities established either specifically for them or in an integrated manner for all science teachers.

Students’ misconceptions of many scientific phenomena or scientific processes have been demonstrated by abundant research; however, investigations into the teachers’ misconceptions are insufficient. Despite the similarity in students’ and teachers’ misconceptions, as shown by the existing findings, a much deeper and more exhaustive study of the relationship between the two remains to be performed. This chapter will report findings of an empirical research study that examined common misconceptions about photosynthesis and respiration held by junior secondary school biology teachers and their students. The current study found the following results: some middle school biology teachers have a more or less incorrect or incomplete understanding of the key concepts in biology, teachers’ and students’ misconceptions display some similarities, these similarities are evident as statistically positive correlations, and the teachers’ misconceptions are likely to be the source of the students’ misconceptions. In conclusion, suggestions for professional training and further research are provided.

Since the eighth curriculum reform of basic education started in 2001 in Mainland China, many changes and innovations have occurred in science education practice and research. This chapter presented the status of science education research (SER) in Mainland China. In order to provide an overview of SER, four Chinese core journals that focused on physics education, chemistry education, biology education, and geography education, respectively, were selected to review and analysis the papers in 2011 and 2012; the results showed the affiliation of researchers and research topics. Moreover, this chapter introduces SER in Mainland China from research fields such as curriculum and textbook, science teaching, science learning, teachers’ professional development, scientific inquiry, and learning progressions and students’ domain-specific cognitive development. In the research fields, the representative studies in physics, chemistry, and biology education were reviewed, because the SER in Mainland China is closely integrated with separate science subjects.

Globalization is a reality nowadays. If the book, The world is flat, by The New York Times columnist Friedman (2005), was mostly speculation for globalization to happen, now we witness globalizatio...

The Xuefeng Tectonic Belt is an important intraplate structural system in the South China Block. Its west margin is up to 1300 km away the present-day continental margin, and the Mesozoic structural trends in this belt are perpendicular to and have no correlation with the Triassic Qinling-Dabie Orogenic Belt. This belt provides important clues for understanding the mechanism of intraplate deformation and the tectonic history of South China. We identified two generations of folding with different strike directions in the Xuefeng Tectonic Belt based on the youngest folding-involved strata and their overprinting relationship. The early one is NE-striking, overprinted by the N–S-striking folds both during Late Jurassic and Late Cretaceous. Thrust faults in the Xuefeng Tectonic Belt mainly show top-to-west thrust movement, which is approximately coeval with the N–S-striking folding. The thrust fault system can be divided into three zones: the root zone with steep thrusts, the middle zone characterized by imbricate thrusts, and the frontal zone with a few shallow thrusts. In addition, two generations of strike-slip faults with different structural trends have been identified: E–W-striking strike-slip faults showing dextral transpression, and NE-striking strike-slip faults with sinistral offset and controlling the upper Cretaceous basins. According to regional geological relationship and structural overprinting, we interpret that the E–W trending strike-slip faults formed in the first stage, whereas the NE-striking strike-slip faults formed later during an E–W-oriented compressional event. Therefore, the principal stress direction varies from NW–SE to E–W.

With the development and implementation of new curriculum standards, the field tests of education reform in senior high schools began in 2004 in four pilot provinces in mainland China. After five years of the reform, it is necessary to know how and to what extent the curriculum standard guides test classroom instruction. The present study was conducted with the aims of quantitatively exploring the alignments between the national High School Biology Curriculum Standard and the standards-based High School Exit Exam (HSEE) of 2009 in the four provinces, using Porter's alignment model. As a result, it was found that none of the four provinces' standardised tests of 2009 analysed were significantly aligned with the national Biology Curriculum Standard. The low alignment indexes are mainly because the four HSEEs analysed generally require lower levels of cognitive skills than that of the Standard. These results deserve universal attention by both policymakers and test developers in mainland China.