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Preservice elementary science teachers’ beliefs and practices influence the kinds of adaptations they make to curricula and the extent to which they are able to enact science lessons in justice-oriented ways. Through this qualitative study, we explored the beliefs and practices of five focal preservice teachers through an analysis of their lesson plans, recorded enactments, and interviews about their science teaching throughout their student teaching experience. We also introduce a framework for expansive sensemaking that integrates beliefs and practices related to four key themes: (1) believing in children’s brilliance, (2) building a collaborative classroom culture, (3) expanding what counts as science, and (4) positioning children as epistemic agents. While teachers varied in their beliefs about and approaches to each of these themes, they demonstrated strengths that illustrate what may be possible for early career teachers, like working to integrate many ways of knowing and being into science lessons, connecting to embodied knowledge, or supporting children to be scientific decision-makers. We discuss implications for teacher preparation programs and for theory development related to justice-oriented teaching in general and expansive sensemaking in particular. 

Building on the literature, we designed a practical framework to support attention to equity and justice in science teacher education coursework. This framework presents four approaches for including justice moves in elementary science lessons, from increasing opportunity and access in science, to increasing identity and representation in science, to expanding what counts as science, to seeing science as a part of justice movements. We analyzed the lesson plans of 16 preservice elementary teachers who were using the practical justice framework. In addition to extensive attention to varying participation structures to support children’s science discourse, preservice teachers also took up more challenging moves such as attending to how children are positioned as scientists, inviting children’s science ideas and hearing the science in their ideas, encouraging decision-making in science practices, and connecting science to issues of justice. They varied in both the number of unique justice moves they took up and the specificity with which they planned for incorporating the moves. We discuss implications for practice and theory-building in relation to supporting preservice teachers in learning to teach science toward equity and justice. 

We report on spectroscopic measurements on the 4f⁷6s²⁸S_7/2^∘−4f⁷(⁸S^∘)6s6p(¹P^∘)⁸P_5/2,7/2transitions at 466.32 nm and 462.85 nm, respectively, in neutral europium-151 and europium-153. The center of gravity frequencies for the 151 and 153 isotopes for both transitions are reported for the first time using saturated absorption spectroscopy. For the 6s6p(¹P^∘)⁸P_5/2state, the center of gravity frequencies were found to be 642,894,493.3(4) MHz and 642,891,693.3(9) MHz for the 151 and 153 isotopes, respectively. The hyperfine constants for the upper state were found to beA(151)=−157.01(3)MHz,B(151)=74.5(4)MHz andA(153)=−69.43(14)MHz,B(153)=191.0(26)MHz. These hyperfine values are all consistent with previously published results except forB(151) that has a small discrepancy. The isotope shift was found to be 2799.54(20) MHz, a small discrepancy with previously published results. For the 6s6p(¹P^∘)⁸P_7/2state, the center of gravity frequencies were found to be 647,708,930.6(6) MHz and 647,705,958.4(26) MHz for the 151 and 153 isotopes, respectively. The hyperfine constants for the upper state were found to beA(151)=−218.66(4)MHz,B(151)=−293.4(8)MHz andA(153)=−97.15(13)MHz,B(153)=−750(3)MHz. These values are all consistent with previously published results except forA(151) that has a small discrepancy. The isotope shift was found to be 2972.8(5) MHz, a small discrepancy with previously measured results. 

Science in the elementary grades is often deprioritized in comparison to ELA and mathematics. We wondered, how comprehensively, frequently, and consistently is science in elementary schools’ schedules? In this study, we reviewed daily schedules for 14 schools in 9 districts across the U.S. to qualitatively examine how science is represented on the daily instructional schedule. These schools were selected as “best case scenarios” recommended by district or state science leaders as places where science is taken seriously. We complement these schedule data with data from 21 interviews with teachers, science specialists, and school leaders to better understand how science actually appears in children’s daily instructional experiences. Our findings suggest that, in these schools, science is taught comprehensively (though not as comprehensively as ELA or mathematics), has the potential for being taught frequently (even in the lower elementary grades), and is taught somewhat consistently (albeit usually in some kind of rotation with social studies). The paper closes with implications for how school schedules could be crafted to make science comprehensive, frequent, and consistent, as well as some pitfalls that could be avoided as schedules are developed. 

Abstract As devices approach the single-nanoparticle scale, the rational assembly of nanomaterial heterojunctions remains a persistent challenge. While optical traps can manipulate objects in three dimensions, to date, nanoscale materials have been trapped primarily in aqueous solvents or vacuum. Here, we demonstrate the use of optical traps to manipulate, align, and assemble metal-seeded nanowire building blocks in a range of organic solvents. Anisotropic radiation pressure generates an optical torque that orients each nanowire, and subsequent trapping of aligned nanowires enables deterministic fabrication of arbitrarily long heterostructures of periodically repeating bismuth-nanocrystal/germanium-nanowire junctions. Heat transport calculations, back-focal-plane interferometry, and optical images reveal that the bismuth nanocrystal melts during trapping, facilitating tip-to-tail “nanosoldering” of the germanium nanowires. These bismuth-semiconductor interfaces may be useful for quantum computing or thermoelectric applications. In addition, the ability to trap nanostructures in oxygen- and water-free organic media broadly expands the library of materials available for optical manipulation and single-particle spectroscopy.