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Abstract Black soldier fly larvae (BSFL) have demonstrated cold tolerance that suggests the presence of cryoprotective molecules. The objective of this research was to investigate if the proteins present in the BSFL have ice recrystallization inhibition (IRI) activity and how different environmental factors affect the activity. Osborne fractionation of the defatted BSFL was performed to separate the proteins based on solubility, then preparative size exclusion chromatography was used to fractionate the albumin fraction by molecular size to isolate IRI or ice binding proteins. The major proteins in the active fractions were identified by mass spectrometry, and molecular dynamic simulations were performed with two proteins identified to investigate their behaviors in an ice-water system. The main finding is the strong IRI activity of the water-soluble BSFL albumin fraction and the column fractionated fraction 1. This fraction had a 40.4-79.9% reduction in ice crystal size at 1% concentration and under a wide pH (3-9) and salt (10-200 mM NaCl) concentration. Pure proteins recovered were sequenced and identified as cuticle proteins by mass spectrometry. One cuticle protein demonstrated strong H-bonding and structural flexibility by molecular dynamic simulations, explaining the IRI and ice binding activity. This is the first time BSFL protein is reported to possess IRI activity, and such protein extract can be feasibly obtained compared to other naturally occurring antifreezing proteins. 

Researchers of teacher education have long advocated that one of the most essential supports to teacher learning of novel instruction practices comes from collaboration. Much of the collaboration literature focuses on the outcomes of teacher collaboration without providing insight into the nature of collaborations. In this work, we seek to understand the collaboration that occurred between five school biology teachers as they designed, enacted, and reflected on a lesson emerging from professional development focused on productive talk. The questions guiding this work include: What was the focus of the LCD teacher group’s collaboration?, What was the nature of the LCD teacher group’s collaboration? and, What role did the group’s collaboration serve in supporting each teacher’s practice? We found that the collaborative space opened-up opportunities for teachers to discuss their practice for the lesson and outside of the lesson itself. Salient to the collaborative space was a sense of support between the teachers as teachers intensively listened to one another, normalized a problematic issue as well as the emotions that they were experiencing by relating to each other, providing advice and words of encouragement. Teachers’ collaboration eased the work of designing and enacting a conceptually challenging lesson. 

This paper examined changes in students' biological reasoning, scientific sensemaking, valuing of science, and fascination in science over the course of a school year after their teacher participated in one of the two professional development programs. One professional development (PD) group emphasized teacher collaboration in revising materials for their classroom, while the other emphasized revision of materials without collaboration among teachers. Results from repeated measures ANOVA showed improvements in students' biological reasoning from the beginning to end of the school year when in classrooms led by teachers who participated in the collaboration-focused PD. Students' scientific sensemaking, valuing of science, or science fascination remained stable across the school year across both PD groups. 

Recent educational reforms conceptualize science classrooms as spaces where students engage in Science-as-Practice to develop deep understandings of scientific phenomena. When students engage in Science-as-Practice they are constructing explanations, arguing from evidence, and evaluating and communicating information to develop scientific knowledge (NGSS Lead States, 2013). This process of learning requires a focus on productive science talk in which students grapple with and socially negotiate their ideas (Kelly, 2014) through interactions involving talk, joint attention, and shared activity aimed at building, negotiating, and refining new understandings of phenomena and relevant science concepts (Ford, 2015; Michaels & O’Connor, 2012). Productive talk requires the ‘nimble’ involvement of the teacher to help students productively contribute their ideas to the class and use them as resources to drive instructional activities supporting the development and refinement of more sophisticated scientific understandings (Christodoulou & Osborne, 2014; González‐Howard & McNeill, 2020). 

While conceptual uncertainties position students to engage in the disciplinary practices of science in meaningful ways, that engagement is dependent on how students respond to and manage such uncertainties. The current study examines various epistemological, social, and affective dynamics and how they influence the management of conceptual uncertainties in one group of middle school students in a science classroom. Using multimodal discourse analysis, we found that students’ persistence in disciplinary engagement is not only dependent on the presence and recognition of conceptual uncertainties but also on how students take up and manage challenges along epistemological, social, and affective dimensions. Our work can inform educators interested in supporting students to navigate the complex and multidimensional dynamics of collaborative sensemaking in service of promoting disciplinary engagement in science. 

While recent reforms in science education envision engaging students in doing science as a way to learn science, less is known about how such an engagement can take hold in the classroom. In an effort to address this gap, this study examines the dynamics of students’ disciplinary engagement in small groups in a middle school science classroom. Using multimodal discourse analysis, we conducted a comparative case analysis of three groups of students to examine the dynamics of their engagement along conceptual, epistemological, social, and affective dimensions. Through this analysis, our findings highlight tensions that emerge along these dimensions and the ways in which students negotiate these tensions in ways that support or hinder disciplinary engagement. 

Recent educational reforms conceptualize science classrooms as spaces where students collaboratively engage in disciplinary practices to construct and evaluate scientific explanations of phenomena. For students to effectively collaborate with each other, they need to develop a shared framing of the nature of the science activity and the expectations surrounding their engagement in it. Such framing does not only pertain to the conceptual work but also involves myriad epistemological, social, and affective dimensions. We conceptualize collaborative disciplinary engagement as the process of aligning the group’s framing along these dimensions and, we argue, student negotiations to achieve this alignment are in part what initiate and sustain collaborative disciplinary engagement in the science classroom. By focusing on student negotiations, this study builds on existing research on group dynamics involved in science learning and contributes nuanced empirical insights on the nature of student negotiations along the conceptual, epistemological, social, and affective dimensions of argumentation in science. Moreover, the findings provide a proof of concept regarding the key role that student negotiations of framing have in driving collaborative disciplinary engagement. The study findings have implications for research and practice to support learners’ productive disciplinary engagement in group work in the science classroom and beyond. 

This study explores the epistemological framing dynamics in one middle school biology classroom and how those dynamics shape students’ collaborative sensemaking in science. We trace how the teacher’s instructional moves shaped students’ framing, and the ways in which that framing influenced students’ learning. Our analysis shows that while the teacher framed small group argumentation activities as spaces for students to generate and negotiate ideas, brief but influential moves at the end of the lesson, which emphasized the correct answer, undermined students’ sensemaking and intellectual authority. These findings have implications for the design of teacher education highlighting the need to promote teachers’ awareness of the impact of their instructional moves in terms of how students frame their efforts in the classroom. 

This work explores epistemological framing dynamics in a middle school biology classroom and how such dynamics shape student engagement and learning opportunities. Our data sources include student and teacher interviews, classroom videos of three multi-day lessons with a focus on argumentation, and work products collected across one academic year. Our analysis reveals that while the teacher made room for students to generate and negotiate ideas, brief but influential moves emphasizing single correct answers undermined students’ sensemaking. These instructional moves, while only occupying a small amount of instructional time, framed students’ sensemaking efforts not as a process to seek the strongest explanation from a number of possibilities, but rather to wait for the correct explanation to be revealed from an authority.