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Learning progressions (LPs) provide researchers with a robust framework to describe the process of students' cognitive development in science and provide teachers with an effective reference to help students' competences develop. In physics education, the understanding of the particle nature of matter (PNM) is important, as it affects students' conceptualization of matter and, over the long term, the entire view of science. Developing a systematic understanding of the PNM requires an effective instruction. Teachers' instruction is heavily influenced by their understanding on students' progression. Therefore, this study first tested and refined students' LPs of PNM. Then, with the lens of LPs, we investigated teachers' perception on the progression. The results show that students' LPs of PNM in teachers' minds are partly different from students' actual situations, as most teachers have not been sufficiently informed of students' conceptual understanding of PNM and especially lack the knowledge of students' understanding in PNM at the lower level. When designing instruction, some teachers did not have an awareness of LP-based instructional design and sometimes neglected students' conceptual development. This study ends with some suggestions for supporting teachers' professional development. [ABSTRACT FROM AUTHOR]

The "Integrated Development of Key Competences" has been identified as the core idea in education to face competition in the 21st century. Similarly, reform efforts in science education emphasize the importance of integrating scientific practices and disciplinary core ideas. The learning progression (LP) is viewed as a robust tool to facilitate this integrated development. In this study, we integrated learning progressions of energy understanding and scientific explanation into an LP-based intervention to facilitate the instructional design of a middle school energy unit. A quasi-experiment was conducted with 3 teachers and their 184 students to examine the effects of the LP-based intervention on teacher instructional actions and student learning outcomes when compared to traditional instruction. Synthesizing video analysis and pre/posttests, the following results were obtained. (1) LP-based intervention influenced the treatment group's instructions. (2) The performance of both the treatment and comparison groups of students improved, but students in the treatment group demonstrated a better understanding of energy and were more competent in constructing scientific explanation. The article concludes by discussing implications for the future curriculum design and professional development of teachers. [ABSTRACT FROM AUTHOR]

Macrophage infiltration is one of the main pathological features of ulcerative colitis (UC) and ferroptosis is a type of nonapoptotic cell death, connecting oxidative stress and inflammation. However, whether ferroptosis occurs in the colon macrophages of UC mice and whether targeting macrophage ferroptosis is an effective approach for UC treatment remain unclear. The present study revealed that macrophage lipid peroxidation was observed in the colon of UC mice. Subsequently, we screened several main components of essential oil from Artemisia argyi and found that β-caryophyllene (BCP) had a good inhibitory effect on macrophage lipid peroxidation. Additionally, ferroptotic macrophages were found to increase the mRNA expression of tumor necrosis factor alpha (Tnf-α) and prostaglandin-endoperoxide synthase 2 (Ptgs2), while BCP can reverse the effects of inflammation activated by ferroptosis. Further molecular mechanism studies revealed that BCP activated the type 2 cannabinoid receptor (CB2R) to inhibit macrophage ferroptosis and its induced inflammatory response both in vivo and in vitro. Taken together, BCP potentially ameliorated experimental colitis inflammation by inhibiting macrophage ferroptosis. These results revealed that macrophage ferroptosis is a potential therapeutic target for UC and identified a novel mechanism of BCP in ameliorating experimental colitis. [ABSTRACT FROM AUTHOR]

The qualities of semi‐dried noodles (SDNs) and fine dried noodles (FIDNs) made of three kinds of wheat flour with different particle sizes were investigated. Rheological analysis showed that the dough of fine flour (D90: 55.8 µm) had better elasticity. The dried noodles of fine flour had high percentage of large polymeric proteins and ordered secondary structure of gluten protein. SDNs of fine flour contained stronger gluten network and had higher hardness and tensile strength. However, the flour particle size of FIDNs with good texture characteristic was larger than that of SDNs, and increasing dryness reduced the strength of gluten network. The dense internal structure was observed in dried noodles of fine flour, and the noodles had lower cooking loss and the best sensory evaluation. For reducing the adverse effect of drying on noodles, fine flour (D90: 55.8–66.8 µm) was required in the production of SDNs and FIDNs. Novelty impact statement: Semi‐dried noodles (SDNs) made of fine flour (D90: 55.8) contained strong gluten network, and their hardness, springiness, chewiness, and tensile strength were at high level. However, the flour particle size (D90: 66.8) of fine dried noodles (FIDNs) with good texture characteristic was larger than that of SDNs. Moreover, the dense internal structure was observed in SDNs and FIDNs made of fine flour, and they had lower cooking loss and the best organoleptic property. [ABSTRACT FROM AUTHOR]

China initiated a new round of science curriculum reform in 2017. Using the tripartite curriculum framework (including policy, programmatic, and classroom curriculum), we introduce and analyse China’s policy curriculum and programmatic curriculum for science in primary school and senior high school, and describe the potential problems hindering the translation of these curricula into the classroom curriculum. We first identify the multiple aims of different stakeholders in science education, some of which influence the science policy curriculum. Then, we present the major changes in how the programmatic curriculum meets the policy curriculum. However, due to extracurricular factors, the current science curriculum reform may not unfold as expected. We end with a discussion of the three major characteristics of the revision process of science curriculum standards in China, some of which might inform the global community of science education. [ABSTRACT FROM AUTHOR]

Abstract: Providing scientific explanations for natural phenomena is a fundamental aim of science; therefore, scientific explanation has been selected as one of the key practices in science education policy documents around the world. To further elaborate on existing educational frameworks of scientific explanation in K–12, we propose a learning progression of scientific explanation based on the Phenomenon‐Theory‐Data‐Reasoning (PTDR) framework. To examine the validation of the PTDR framework for scientific explanation and the learning progression based on it, we developed the Scientific Explanation Progression Assessment to investigate students’ performance (Grades 8–12 students, N = 4,554) on scientific explanations. A Rasch analysis and other statistical tests together indicated the validity of the PTDR framework for scientific explanation and the learning progression derived from this framework. We end with a discussion of the implications for future design of instruction and assessment. © 2017 Wiley Periodicals, Inc. J Res Sci Teach 55: 299–317, 2018 [ABSTRACT FROM AUTHOR]

This paper presents a revised learning progression for the energy concept and initial findings on diverse progressions among subgroups of sample students. The revised learning progression describes how students progress towards an understanding of the energy concept along two progress variables identified from previous studies – key ideas about energy and levels of conceptual development. To assess students understanding with respect to the revised learning progression, we created a specific instrument, the Energy Concept Progression Assessment (ECPA) based on previous work on assessing students’ understanding of energy. After iteratively refining the instrument in two pilot studies, the ECPA was administered to a total of 4550 students (Grades 8–12) from schools in two districts in a major city in Mainland China. Rasch analysis was used to examine the validity of the revised learning progression and explore factors explaining different progressions. Our results confirm the validity of the four conceptual development levels. In addition, we found that although following a similar progression pattern, students’ progression rate was significantly influenced by environmental factors such as school type. In the discussion of our findings, we address the non-linear and complex nature of students’ progression in understanding energy. We conclude with illuminating our research's implication for curriculum design and energy teaching. [ABSTRACT FROM PUBLISHER]

The construction of scientific explanations, as a key scientific practice, has been highlighted in policy documents. However, research suggests that students lack competence in constructing scientific explanations and this is due to a lack of appropriate scaffolding in science instruction. To address this problem, researchers have developed the Claim-Evidence-Reasoning framework, as scaffolding for constructing scientific explanations. Derived from that framework, a learning progression of scientific explanations has been proposed for the entry point of K-12 science education. However, a clarification on the theoretical foundation of the Claim-Evidence-Reasoning framework and a further extending of the learning progression of scientific explanation has been called for. Therefore, in this paper we aim to add to this research area by first refining its theoretical foundations. More specifically, through linking perspectives on scientific explanations in philosophy of science and in science education, we develop the Phenomena-Theory-Data-Reasoning framework. Then we design a hypothetical learning progression of scientific explanation, based on the Phenomena-Theory-Data-Reasoning framework. The paper ends with a discussion of implications for future research and instruction on scientific explanation in science education. [ABSTRACT FROM AUTHOR]

The accuracy of background clutter model is a key factor which determines the performance of a constant false alarm rate (CFAR) target detection method. G distribution is one of the optimal statistic models in the synthetic aperture radar (SAR) image background clutter modeling and can accurately model various complex background clutters in the SAR images. But the application of the distribution is greatly limited by its disadvantages that the parameter estimation is complex and the local detection threshold is difficult to be obtained. In order to solve the above-mentioned problems, an synthetic aperture radar CFAR target detection method using the logarithmic cumulant (MoLC) + method of moment (MoM)-based G distribution clutter model is proposed. In the method, G distribution is used for modeling the background clutters, a new MoLC+MoM-based parameter estimation method coupled with a fast iterative algorithm is used for estimating the parameters of G distribution and an exquisite dichotomy method is used for obtaining the local detection threshold of CFAR detection, which greatly improves the computational efficiency, detection performance and environmental adaptability of CFAR detection. Experimental results show that the proposed SAR CFAR target detection method has good target detection performance in various complex background clutter environments. [ABSTRACT FROM AUTHOR]

SnS and SnS:In films were deposited onto glass substrates by chemical bath technique. The structure and surface morphology of the SnS:In films were studied by X-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. Energy dispersive spectroscopy (EDS) showed the existence of In in the films. The undoped SnS film exhibited a rather high resistivity and InCl3 could reduce the resistivity of these films by two orders approximately. The band gaps of the SnS and SnS:In films were evaluated from the optical transmission spectra. [ABSTRACT FROM AUTHOR]

This paper introduces a method to realize digital television transmission based on asynchronous transfer mode (ATM), a technology based on fast packet switching. Choosing the integral multiple length of an ATM cell payload to equal to the length of an MPEG transport stream packet, an MPEG transport stream packet can be inextenso loaded by several ATM cells and transformed into ATM cells. Using ATM virtual connection technology and B-ISDN, the interoperability between ATM and DTV may be realized, and DTV signal transmission may also be realized finally. [ABSTRACT FROM AUTHOR]