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Abstract We present 0.″4 resolution imaging polarimetry at 8.7, 10.3, and 12.5 μ m, obtained with CanariCam at the Gran Telescopio Canarias, of the central 0.11 pc × 0.28 pc (4.″2 × 10.″8) region of W51 IRS2. The polarization, as high as ∼14%, arises from silicate particles aligned by the interstellar magnetic field ( B -field). We separate, or unfold, the polarization of each sightline into emission and absorption components, from which we infer the morphologies of the corresponding projected B -fields that thread the emitting- and foreground-absorbing regions. We conclude that the projected B -field in the foreground material is part of the larger-scale ambient field. The morphology of the projected B -field in the mid-infrared (mid-IR) emitting region spanning the cometary H ii region W51 IRS2W is similar to that in the absorbing region. Elsewhere, the two B -fields differ significantly with no clear relationship between them. The B -field across the W51 IRS2W cometary core appears to be an integral part of a champagne outflow of gas originating in the core and dominating the energetics there. The bipolar outflow, W51north jet, that appears to originate at or near SMA1/N1 coincides almost exactly with a clearly demarcated north–south swath of lower polarization. While speculative, comparison of mid-IR and submillimeter polarimetry on two different scales may support a picture in which SMA1/N1 plays a major role in the B -field structure across W51 IRS2. 

Abstract We present the first mid-IR detection of the linear polarization toward the star CygOB2-12, a luminous blue hypergiant that, withA_V≈ 10 mag of foreground extinction, is a benchmark in the study of the properties of dust in the diffuse interstellar medium. The 8–13μm spectropolarimetry, obtained with the CanariCam multimode camera at the Gran Telescopio CANARIAS shows clear trends with wavelength characteristic of silicate grains aligned in the interstellar magnetic field. The maximum polarization, detected with 7.8σstatistical significance near 10.2μm, is (1.24 ± 0.28)% with position angle 126° ± 8°. We comment on these measurements in the context of recent models for the dust composition in the diffuse interstellar medium. 

Purpose The purpose of this paper is to explore the designed cultural ecology of a hip-hop and computational science, technology, engineering, and mathematics (STEM) camp and the ways in which that ecology contributed to culturally sustaining learning experiences for middle school youth. In using the principles of hip-hop as a CSP for design, the authors question how and what practices were supported or emerged and how they became resources for youth engagement in the space. Design/methodology/approach The overall methodology was design research. Through interpretive analysis, it uses an example of four Black girls participating in the camp as they build a computer-controlled DJ battle station. Findings Through a close examination of youth interactions in the designed environment – looking at their communication, spatial arrangements, choices and uses of materials and tools during collaborative project work – the authors show how a learning ecology, designed based on hip-hop and computational practices and shaped by the history and practices of the dance center where the program was held, provided access to ideational, relational, spatial and material resources that became relevant to learning through computational making. The authors also show how youth engagement in the hip-hop computational making learning ecology allowed practices to emerge that led to expansive learning experiences that redefine what it means to engage in computing. Research limitations/implications Implications include how such ecologies might arrange relations of ideas, tools, materials, space and people to support learning and positive identity development. Originality/value Supporting culturally sustaining computational STEM pedagogies, the article argues two original points in informal youth learning 1) an expanded definition of computing based on making grammars and the cultural practices of hip-hop, and 2) attention to cultural ecologies in designing and understanding computational STEM learning environments. 

Black males are often underrepresented in postsecondary education settings and frequently encounter many barriers in getting to college. Our aim in this qualitative investigation was to understand the precollege and college experiences of Black males who successfully enrolled in a postsecondary institution. Through a focus group interview, seven Black males in a living and learning community shared their experiences prior to and during enrollment at a highly selective, predominantly White institution. We used the grounded theory approach ( Strauss & Corbin, 1998 ) to analyze the focus group data and pinpoint thematic explanations of precollegiate and collegiate experiences of Black males. Based on the thematic findings, we offer specific recommendations on how school counselors can help Black males prepare and eventually matriculate in higher education.