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Context. The fundamental process of star formation in galaxies involves the intricate interplay between the fueling of star formation via molecular gas and the feedback from recently formed massive stars that can, in turn, hinder the conversion of gas into stars. This process, by which galaxies evolve, is also closely connected to the intrinsic properties of the interstellar medium (ISM), such as structure, density, pressure, and metallicity. Aims. To study the role that different molecular and atomic phases of the ISM play in star formation, and to characterize their physical conditions, we zoom into our nearest neighboring galaxy, the Large Magellanic Cloud (LMC; 50 kpc), the most convenient laboratory in which to study the effects of the lower metal abundance on the properties of the ISM. The LMC offers a view of the ISM and star formation conditions in a low-metallicity (Z~ 0.5 Z_⊙) environment similar, in that regard, to the epoch of the peak of star formation in the earlier Universe (z~ 1.5). Following up on studies carried out at galactic scales in low-Z galaxies, we present an unprecedentedly detailed analysis of well-known star-forming regions (SFRs) at a spatial resolution of a few parsecs. Methods. We mapped a 610pc× 260pc region in the LMC molecular ridge in [C II]λ158 µm and the [O III]λ88 µm using the FIFI-LS instrument on the SOFIA telescope. We compared the data with the distribution of the CO(2−1) emission from ALMA, the modeled total infrared luminosity, and the Spitzer/MIPS 24 µm continuum and Hα. Results. We present new large maps of [CII] and [OIII] and perform a first comparison with CO(2−1) line and LTIR emission. We also provide a detailed description of the observing strategy with SOFIA/FIFI-LS and the data reduction process. Conclusions. We find that [CII] and [OIII] emission is associated with the SFRs in the molecular ridge, but also extends throughout the mapped region, and is not obviously associated with ongoing star formation. The CO emission is clumpier than the [C II] emission and we find plentiful [C II] present where there is little CO emission, possibly holding important implications for “CO-dark” gas. We find a clear trend of the L_[C II]/L_TIRratio decreasing with increasing L_TIRin the full range. This suggests a strong link between the “[C II]-deficit” and the local physical conditions instead of global properties. 

This mixed-methods observational study analyzes Advanced Placement (AP) Biology teachers’ engagement in microblogging for their professional development (PD). Data from three hashtag-based Twitter communities, #apbiochat, #apbioleaderacad, and #apbioleaderacademy (121 users; 2,253 tweets), are analyzed using methodological approaches including educational data mining, qualitative two-cycle content analysis, social network analysis, linear and logistic regression analyses, and hierarchical linear modeling. Results indicate that Twitter adheres to standards of high-quality PD and has the potential to complement more traditional PD activities. Notably, Twitter’s non-hierarchical leadership affords shared content creation and distribution. Additionally, Twitter allows for different temporal participation patterns and supports the personalization of learning experiences aligned to teachers’ needs and preferences. Furthermore, teachers frame their interactions on Twitter positively, thus, creating a supportive environment for professional learning that might reduce teachers’ perceived isolation. Therefore, policy makers and school leaders should feel empowered to encourage teachers to use microblogging complementary to other PD activities. 

This empirical study explored participation patterns of 1,733 Advanced Placement (AP) Physics teachers in the online AP teacher community (APTC) following the redesigned AP science examinations in the United States. We identified profiles of teachers with different levels of engagement in this peer-based online learning community. Our results provide insight into underrepresented user groups and the development of more personalized online teacher support systems. Our analysis suggested that teachers’ knowledge and experience, the enactment of AP practices, challenges with the AP redesign, and AP workload were all significantly associated with changes in the probability of teachers becoming APTC users. This indicated that the APTC attracted a non-representative population sample of all AP physics teachers. However, most teacher, teaching, and school characteristics provided no indication as to whether APTC users were posters or lurkers. 

This paper describes a study using a quasi-experimental design to examine teachers’ preparations in low-income schools for a revised version of the AP Biology and AP Chemistry examinations, and explores variables associated with student scores on the AP science examinations that are better than would be predicted based on their PSAT scores. Considering the frequently-measured achievement gap on high-stakes examinations, identifying “what works” to raise student performance of at-risk students is an urgent area for research. The analyses indicate that (a) districts per-student funding allocations, (b) teachers’ knowledge and experience, and (c) teachers’ participation in professional development activities with a responsive agenda and effective support for teaching the redesigned AP science course are significantly associated with higher students’ average performance on the AP science exams than would be predicted. 

Two additions impacting tables 3 and 4 in ref. [1] are presented in the following. No significant impact is found for other results or figures in ref. [1].