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Learning assistants (LAs) play an important role in inquiry-oriented physics instruction in large classrooms. LAs increase the teacher-student ratio and provide timely support to student exploration. Questioning is believed to be an advantageous strategy for LAs to scaffold student learning and maintain students as the agent of knowledge construction. Unfortunately, there are few instruments for the measurement and preparation of LAs' competency of questioning. It remains obscure how LAs use questioning in their interaction with students and how their questioning contributes to students' conceptual understanding. In this study, we developed two instruments that included a coding scheme to assess LAs' practice of questioning from class videos and written questions to assess LAs' knowledge of analyzing various situations that they may encounter while teaching introductory physics. We used the two instruments to measure performed and narrated pedagogical content knowledge of questioning (PCK-Q) of four LAs in two inquiry-based physics courses taught online. We examined the validity and reliability of both instruments, gauged LA-student interaction in online settings, delineated the LAs' PCK-Q, and suggested how the LAs' questioning contributed to students' physics learning. We also discussed the use of the two instruments for the purposes of both LA assessment and preparation.

Inquiry teaching in science education has been widely advocated for decades. It is a critical learning objective in many science teacher preparation programs. Despite its importance, it is not effectively implemented in science classrooms. One of the reasons is the lack of reliable and valid instruments that provide practical definition, concrete guideline, and objective assessment for the practice of inquiry teaching. To fill this gap, we designed a 3E rubric based on the 5E learning model as one specific form of inquiry teaching to measure preservice teachers' practice at different phases of a science lesson. In this study, we thoroughly introduced the 3E rubric and its use. Through drawing on 76 elementary pre-service science teachers' teaching videos, we analyzed its reliability and validity with the tools of Intraclass Correlation Coefficient, Fleiss' kappa, and Pearson correlation. According to the results, the 3E rubric is a reliable and valid tool to assess pre-service teachers' practical knowledge of inquiry teaching. The contributions of this rubric to the teaching and research in science teacher preparation are discussed and future research directions are proposed.

High-stakes testing (HST) is critical in the educational system of East-Asian countries like China, and the ongoing standards-based reform in many Western countries like the USA. HST has been criticized for corrupting an educational system through means like disengaging students from authentic learning. It seems that students' affective learning would be promoted if HST were abandoned. In this study, we used the mixed-method approach to investigate this hypothetical question by comparing the physics identity of high-school students in an HST-oriented educational context and college students who have transferred from an HST-oriented context to an almost HST-free one in China. We administered a physics identity survey with 108 students from two physics classes in a key high school and 233 undergraduate physics majors in a top-tier university who were separated by Gaokao as the most life-shaping test in China. We also interviewed sample participants about their physics learning. The data show the freshmen in college had a significantly higher average physics identity than the high-school students did. In the undergraduate physics program, the average physics identity had a deteriorating pattern from the freshmen, sophomores, to juniors. From high school to college, the students' intention of pursuing physics as a major or career was similarly low. Differently, the students' perception of lecturing changed, so did their self-discipline. Together, the findings suggested that simply discarding HST would not promote students' affective learning. An alternative was needed to replace the extrinsic pressure from HST, which could be either students' intrinsic engine of learning or another rewarding or coercive system.

Despite the importance of computer science education and computational thinking, there have been limited examples of computer science education at K-12 classrooms that authentically represents the work of computer scientists, especially programming. One reason is the lack of a measurable definition of computational thinking and a programming language friendly to K-12 students. In this case study, we used a text-based declarative programming language named SPARC to integrate computer science into the topic of the atomic structure. We also designed a rubric for the assessment of computational thinking that included two categories of abstraction and programming. We examined the experiences of two 8th-grade students representing those who have some experience with computer science and programming and those without any experience. The findings support the feasibility of integrating computer science and science and exposing middle-school students to text-based programming. We also discussed the pedagogical concerns in light of the students' challenges.

The purpose of this action research is to introduce a debate activity contextualized in a scientific topic and explore its effectiveness in prompting teacher candidates' (TC) argumentation skills and affective perception of argumentation. We also investigate the separate impacts of the different aspects of the debate activity. Through comparing the quality of structural argumentation from 28 elementary TCs before and after the activity, we find that the debate has enhanced the TCs' argumentation skills in terms of the use of rebuttals. The transcript data further reveals that the confrontational aspect of the debate, i.e. Clash and Extension, are most effective in arousing high-level arguments as well as most risky in triggering negative TC attitudes towards argumentation. Through reflecting on our action of implementing the debate, we suggest a revised rubric for argumentation assessment in which sophisticated argumentation skills are epitomized by not only rebutting but also synthesizing various information and multiple perspectives to reach a conclusion.

Online teacher education is an important alternative in response to the problem of teacher shortage. The format of interaction is critical in leveraging social and intellectual connection between learners. Yet, few studies have examined this issue in online teacher preparation. In this study, we examined two commonly used interactional formats that are synchronous and asynchronous interaction. We separated 145 pre-service science teachers into four groups experiencing face-to-face interaction (G1), synchronous interaction through online meetings (G2), asynchronous interaction through online forum (G3), and individual work without interaction (G4). The four groups received the same curriculum and the impact of instructors on peer interaction was controlled. We compared pre-service teachers' social and cognitive presences and their science teaching using the 5E model between the four groups. The results show that the two groups with synchronous interaction (G1 and G2) outperformed the one with asynchronous interaction (G3) and no interaction (G4) in social presence, cognitive presence, and science teaching. Pearson correlation data suggest that the participants' social presence correlated largely with cognitive presence and their teaching practice to some extent. However, cognitive presence correlated poorly with the teaching practice. The findings provide empirical evidence supporting the importance of interaction in online instruction. Synchronicity was positively related to the pre-service teachers' connection to peers in the learning community, which entailed better interaction with content but might not necessarily promote their cognitive learning outcome. Implications for online teacher preparation were also discussed.

Summary: Background: Bronchopulmonary dysplasia (BPD) is the primary severe complication of preterm birth. Severe BPD was associated with higher risks of mortality, more postnatal growth failure, long term respiratory and neurological developmental retardation. Inflammation plays a central role in alveolar simplification and dysregulated vascularization of BPD. There is no effective treatment to improve BPD severity in clinical practice. Our previous clinical study showed autologous cord blood mononuclear cells (ACBMNCs) infusion could reduce the respiratory support duration safely and potential improved BPD severity. Abundant preclinical studies have reported the immunomodulation effect as an important mechanism underlying the beneficial results of stem cell therapies in preventing and treating BPD. However, clinical studies assessing the immunomodulatory effect after stem cells therapy were rare. This study was to investigate the effect of ACBMNCs infusion soon after birth on prevention for severe BPD and long term outcomes in very preterm neonates. The immune cells and inflammatory biomarkers were detected to investigate the underlying immunomodulatory mechanisms. Methods: This single-center, prospective, investigator-initiated, non-randomized trial with blinded outcome assessment aimed to assess the effect of a single intravenous infusion of ACBMNCs in preventing severe BPD (moderate or severe BPD at 36 weeks of gestational age or discharge home) in surviving very preterm neonates less than 32 gestational weeks. Patients admitted to the Neonatal Intensive Care Unit (NICU) of Guangdong Women and Children Hospital from July 01, 2018 to January 1, 2020 were assigned to receiving a targeted dosage of 5 × 107 cells/kg ACBMNC or normal saline intravenously within 24 h after enrollment. Incidence of moderate or severe BPD in survivors were investigated as the primary short term outcome. Growth, respiratory and neurological development were assessed as long term outcomes at corrected age of 18–24 month-old. Immune cells and inflammatory biomarkers were detected for potential mechanism investigation. The trial was registered at ClinicalTrials.gov (NCT02999373). Findings: Six-two infants were enrolled, of which 29 were enrolled to intervention group, 33 to control group. Moderate or severe BPD in survivors significantly decreased in intervention group (adjusted p = 0.021). The number of patients needed to treat to gain one moderate or severe BPD-free survival was 5 (95% confidence interval: 3–20). Survivors in the intervention group had a significantly higher chance to be extubated than infants in the control group (adjusted p = 0.018). There was no statistical significant difference in total BPD incidence (adjusted p = 0.106) or mortality (p = 1.000). Incidence of developmental delay reduced in intervention group in long term follow-up (adjusted p = 0.047). Specific immune cells including proportion of T cells (p = 0.04) and CD4+ T cells in lymphocytes (p = 0.03), and CD4+ CD25+ forkhead box protein 3 (FoxP3)+ regulatory T cells in CD4+ T cells increased significantly after ACBMNCs intervention (p ＜ 0.001). Anti-inflammatory factor IL-10 was higher (p = 0.03), while pro-inflammatory factor such as TNF-a (p = 0.03) and C reactive protein (p ＜ 0.001) level was lower in intervention group than in control group after intervention. Interpretation: ACBMNCs could prevent moderate or severe BPD in surviving very premature neonates and might improve neurodevelopmental outcomes in long term. An immunomodulatory effect of MNCs contributed to the improvement of BPD severity. Funding: This work was supported by National Key R&D Program of China (2021YFC2701700), National Natural Science Foundation of China (82101817, 82171714, 8187060625), Guangzhou science and technology program (202102080104).

Formal teacher preparation programs are facing the challenge of ineffective instruction of educational theories. It is partly because educational theories are taught through direct instruction, which could lead to problems such as impersonality and low motivation of pre-service teachers. In addition, it is also an unwieldy task for teacher educators to cover meaningfully a tremendous amount of theories through direct instruction within a limited time. This study presents an innovative approach of Inquiry-based Pedagogical Instruction (IPI) as a possible solution. The IPI approach has two key features: explicit modeling and scaffolding. In this quasi-experimental study, I compare IPI and direct instruction in promoting pre-service teachers' competence in terms of their knowledge associated with science teaching and their disposition in terms of their sense of belonging to science and science teaching. The participants are 39 pre-service teachers in Phase 1 with 23 of them receiving IPI and the other 16 receiving direct instruction and 92 pre-service teachers in Phase 2 with 42 receiving IPI and 50 receiving direct instruction. The results from two-way ANOVA and effect size analyses suggest that IPI is a promising alternative to direct instruction for the instruction of pedagogical knowledge. IPI has the potential to empower pre-service teachers with the competence and disposition with which they are capable and willing to construct their knowledge of teaching. Implications for future research are also discussed.

Despite the importance of scientific argumentation, it rarely occurs in science classrooms. Researchers have designed argumentation interventions to bridge this gap, but those efforts have limited impacts on transforming existing classroom practices. Argumentation is a linguistically social interaction. It is necessary to go beyond understanding the input and output of an argumentation innovation and comprehend the interactive process. In this case study, my focus dealt with understanding how a high school physics class adapted argumentation practices. I scrutinised the intellectual ecology of that classroom with a focus on the social dynamic of individuals during argumentation through the lens of interlocutors' positions. Through close observation of a physics teacher and his 23 high school students for 6 months, I summarised the patterns of how individual variation in the competences of scientific content knowledge and rhetoric argumentation skills shaped the social dynamic of classroom argumentation, and then the adaption of argumentation practices. With the findings, I suggested features advantageous for argumentation implementation, such as comparably strong academic competences and externally motivating tasks. I also discussed the implications for argumentation implementation in high school science classes.

Inquiry, central in science education reforms for decades, is a critical element required in many teacher education programs. However, the instruction of inquiry-oriented pedagogies in those programs has limited impacts on science preservice teachers (PSTs) who arefvn the agent of transforming classroom instruction. The challenges include the limited time PSTs are exposed to the instruction of inquiry in teacher education programs, the gap between educational theories and field practicum of inquiry to which PSTs are exposed, and the less engaging approach to the instruction of educational theories. At the elementary level, there is an additional challenge of PSTs' low motivation toward science and science teaching. In response to these challenges, we designed an innovative approach of scaffolding pedagogical instruction (SPI) and examined its effectiveness in promoting PSTs' competence and disposition toward science and science teaching. In this article, we thoroughly describe the design of SPI and the instrument measuring the learning outcomes. We apply paired t tests to compare 85 elementary PSTs' knowledge of inquiry teaching as well as their science identity and science teacher identity before and after receiving SPI. The findings suggest a significantly positive impact of SPI in preparing PSTs with the competence in and disposition toward inquiry teaching.

This study is focused on student recognition beliefs as related to a role identity development. More specifically, using the theoretical framework of physics identity and emotional scaffolding, we investigate the impact of two types of recognizing strategies, i.e., explicit (ER) and implicit recognizing (IR), on high school students' sense of recognition and physics identity. ER is teachers directly conveying their acknowledgment of students' qualities or abilities, such as acknowledging good work and expressing faith in student ability, and IR is teachers indirectly acknowledging students' qualities or abilities via assigning them a position or a task that demands those qualities or abilities, such as valuing student opinions and assigning a challenging task. Through six longitudinal surveys for one year, we trace the physics identity development of 134 students from three high school physics classes as well as aspects related to physics identity construction including interest, competence beliefs, and sense of recognition. The patterns suggest that the recognizing strategies used by the teachers relate to a positive shift in students'sense of recognition, which in turn facilitates the development of a physics identity. The post-interviews with six students from the three classes reveal possible mechanisms by which ER and IR strategies are internalized by students. Our findings indicate that the synergy with ER and IR strategies used as well as the nature of the activities (i.e., attainable success) are critical features of effective teacher recognition that can be internalized by the student.

Students enter physics classes with negative attitudes towards physics compared to the other sciences. Female students are more likely to opt out of a second higher-level physics course. Thus, the broad goal of this work is to better understand how to have the most lasting positive impact on female students' attitudes and motivations towards learning physics after a single physics course in high school. Through longitudinal case studies of six female students using the frameworks of episodic memory and physics identity, we explore the most impactful features of students' high school physics experiences. The data is drawn from three years of student interviews and one initial student survey. Our results indicate that the students could remember in detail and with longevity their experiences with physics causing high arousal and negative initial valence, such as teachers presenting physics knowledge in a counter-intuitive way. The students can remember the context but not the details of their experiences with physics causing low arousal and non-neutral valence, such as their teacher sharing a story about physics. Experiences that were eventually tied to positive valence had positive impacts on female students' physics identity maintenance, such as problem solving activities where no one was left behind.

Scientific argumentation is an important learning objective in science education. It is also an effective instructional approach to constructivist science learning. The implementation of argumentation in school settings requires science teachers, who are pivotal agents of transforming classroom practices, to develop sophisticated knowledge of argumentation. However, there is a lack of understanding about science teachers' knowledge of argumentation, especially the dialogic meaning of argumentation. In this case study, we closely examine a high school physics teacher's argumentation-related pedagogic content knowledge (PCK) in the context of dialogic argumentation. We synthesize the teacher's performed PCK from his argumentation practices and narrated PCK from his reflection on the argumentation practices, from which we summarize his PCK of argumentation from the perspectives of orientation, instructional strategies, students, curriculum, and assessment. Finally, we describe the teacher's perception and adaption of argumentation in his class. We also identity the barriers to argumentation implementation in this particular case and suggest solutions to overcome these barriers.

Science education in China is Subject Matter Knowledge (SMK) oriented in that SMK understanding is the major benchmark to assess students' achievement in science learning. Such an orientation causes students to overemphasize the memorization of SMK and neglect other indispensable components of science, such as scientific attitudes and research skills. The central government in China launched an educational innovation known as New Curriculum Reform in 2003. Considerable progress has been made in the past 11 years in regard to theoretical understandings and administrative priorities, but little progress has been made in terms of classroom instruction and scientific literacy cultivation at the secondary level. Under the pressure of nationwide standardized exams, any educational innovations are unlikely to be accepted unless there is robust evidence suggesting their efficacy in promoting students' achievements on exams, or even attempted unless teachers are assured such attempts will not negatively impact such achievement. Argumentation-integrated curriculum is one such innovation. Scientific argumentation is an essential scientific activity that leads to the development of an explanation based on empirical evidence. An initial foundation of SMK, in terms of the necessary background knowledge, is considered by many to be a vital component of argumentation and an enhanced SMK is one of the intended products of argumentation. The purpose of this sequential explanatory mixed methods study was to investigate the relationship between Chinese students' SMK levels and argumentation pedagogy and to provide insights into a possible research agenda focused on implementing argumentation in a heavily SMK-oriented context.

Aiming at the deficiencies of the sparrow search algorithm (SSA), such as being easily disturbed by the local optimal and deficient optimization accuracy, a multi-strategy sparrow search algorithm with selective ensemble (MSESSA) is proposed. Firstly, three novel strategies in the strategy pool are proposed: variable logarithmic spiral saltation learning enhances global search capability, neighborhood-guided learning accelerates local search convergence, and adaptive Gaussian random walk coordinates exploration and exploitation. Secondly, the idea of selective ensemble is adopted to select an appropriate strategy in the current stage with the aid of the priority roulette selection method. In addition, the modified boundary processing mechanism adjusts the transgressive sparrows' locations. The random relocation method is for discoverers and alerters to conduct global search in a large range, and the relocation method based on the optimal and suboptimal of the population is for scroungers to conduct better local search. Finally, MSESSA is tested on CEC 2017 suites. The function test, Wilcoxon test, and ablation experiment results show that MSESSA achieves better comprehensive performance than 13 other advanced algorithms. In four engineering optimization problems, the stability, effectiveness, and superiority of MSESSA are systematically verified, which has significant advantages and can reduce the design cost. [ABSTRACT FROM AUTHOR]