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For transportation hubs, leveraging pedestrian flows for commercial activities presents an effective strategy for funding maintenance and infrastructure improvements. However, this introduces new challenges, as consumer behaviors can disrupt pedestrian flow and efficiency. To optimize both retail potential and pedestrian efficiency, careful strategic planning in store layout and facility dimensions was done by expert judgement due to the complexity in pedestrian dynamics in the retail areas of transportation hubs. This paper introduces an attention-based movement model to simulate these dynamics. By simulating retail potential of an area through the duration of visual attention it receives, and pedestrian efficiency via speed loss in pedestrian walking behaviors, the study further explores how design features can influence the retail potential and pedestrian efficiency in a bi-directional corridor inside a transportation hub. 

The National Science Board has declared that the long-term vitality of the U.S. workforce relies on the full range of science, technology, engineering, and mathematics (STEM) career pathways being available to all Americans. This declaration was premised on the increasing diversity in the U.S. population [1] and the need for multiple perspectives on the complex problems faced by society [2]. Thus, the National Science Foundation, the National Academies of Science, Engineering, and Medicine, the American Institutes of Research, and the Council of Graduate Schools have stated that the increased participation of women and members of racially minoritized and marginalized (RMM, including Black, Hispanic/Latinx, and Indigenous) groups in STEM is imperative to maintain the U.S. standing as a global leader in innovation. Because engineering doctoral graduates account for a large share of the innovation workforce [3], the ongoing lack of diversity in the engineering doctoral workforce remains a problem with far-reaching implications for the U.S. economy. The ‘mold’ for an engineering doctoral student was created by graduate education's earliest beneficiaries: young, White, and single men. Students who fall outside this mold, including women, people of color, older people, people with children, and people with disabilities are more likely than their traditional graduate student counterparts to report climate-related issues [4]. While some studies of university or campus-level climate for students have included doctoral students in general, few studies disaggregate findings by discipline or by demographic categories beyond gender identity and race/ethnicity. In engineering, Riley, Slaton, and Pawley’s [5] observed that the engineering education research community tends to take up issues of diversity focused on “women and [racial and ethnic] minorities while queerness, class, nationality, disability, age, and other forms of difference are, for the most part, not seen as requiring address”. This literature review was conducted as a preliminary assessment of the available research literature produced by the engineering education community on organizational climate affecting the retention of engineering doctoral students from diverse backgrounds. We seek to understand this specific student group’s retention as an organizational climate issue and use an intersectional approach to consider the meaning and relevance of students’ belonging, simultaneously to multiple social categories, such as gender identity, sexual orientation, socioeconomic background, race/ethnicity, and disability status within the context of engineering doctoral education as a first step to building a climate survey instrument. Searches on February 2, 2023, for existing scoping reviews and systematic reviews on this topic conducted on JBI Evidence Synthesis, the Cochrane Database of Systematic Reviews, and the Campbell Collaboration did not provide results [6]. The objective of this literature review is to explore how the concept of ‘climate’ is being used in the context of doctoral engineering student retention to degree completion and gather a body of evidence of climate factors. To do this, we conducted a targeted literature review and used intersectionality [7] [8] as our approach to interpreting the literature, as we aim to understand how climate affects the retention of engineering doctoral students from diverse backgrounds. In this paper, we first briefly present our understanding of organizational climate and intersectionality, then we explain our methodology, followed by results and finally discuss our analysis of the climate literature in engineering. 

The Cambrian explosion, one of the most consequential biological revolutions in Earth history, occurred in two phases separated by the Sinsk event, the first major extinction of the Phanerozoic. Trilobite fossil data show that Series 2 strata in the Ross Orogen, Antarctica, and Delamerian Orogen, Australia, record nearly identical and synchronous tectono-sedimentary shifts marking the Sinsk event. These resulted from an abrupt pulse of contractional supracrustal deformation on both continents during thePararaia janeaetrilobite Zone. The Sinsk event extinction was triggered by initial Ross/Delamerian supracrustal contraction along the edge of Gondwana, which caused a cascading series of geodynamic, paleoenvironmental, and biotic changes, including (i) loss of shallow marine carbonate habitats along the Gondwanan margin; (ii) tectonic transformation to extensional tectonics within the Gondwanan interior; (iii) extrusion of the Kalkarindji large igneous province; (iv) release of large volumes of volcanic gasses; and (v) rapid climatic change, including incursions of marine anoxic waters and collapse of shallow marine ecosystems. 

Phylum Tardigrada (water bears), well known for their cryptobiosis, includes small invertebrates with four paired limbs and is divided into two classes: Eutardigrada and Heterotardigrada. The evolutionary origin of Tardigrada is known to lie within the lobopodians, which are extinct soft-bodied worms with lobopodous limbs mostly discovered at sites of exceptionally well-preserved fossils. Contrary to their closest relatives, onychophorans and euarthropods, the origin of morphological characters of tardigrades remains unclear, and detailed comparison with the lobopodians has not been well explored. Here, we present detailed morphological comparison between tardigrades and Cambrian lobopodians, with a phylogenetic analysis encompassing most of the lobopodians and three panarthropod phyla. The results indicate that the ancestral tardigrades likely had a Cambrian lobopodian–like morphology and shared most recent ancestry with the luolishaniids. Internal relationships within Tardigrada indicate that the ancestral tardigrade had a vermiform body shape without segmental plates, but possessed cuticular structures surrounding the mouth opening, and lobopodous legs terminating with claws, but without digits. This finding is in contrast to the long-standing stygarctid-like ancestor hypothesis. The highly compact and miniaturized body plan of tardigrades evolved after the tardigrade lineage diverged from an ancient shared ancestor with the luolishaniids. 

Abstract We present JWST NIRCam (F356W and F444W filters) and MIRI (F770W) images and NIRSpec Integral Field Unit (IFU) spectroscopy of the young Galactic supernova remnant Cassiopeia A (Cas A) to probe the physical conditions for molecular CO formation and destruction in supernova ejecta. We obtained the data as part of a JWST survey of Cas A. The NIRCam and MIRI images map the spatial distributions of synchrotron radiation, Ar-rich ejecta, and CO on both large and small scales, revealing remarkably complex structures. The CO emission is stronger at the outer layers than the Ar ejecta, which indicates the re-formation of CO molecules behind the reverse shock. NIRSpec-IFU spectra (3–5.5μm) were obtained toward two representative knots in the NE and S fields that show very different nucleosynthesis characteristics. Both regions are dominated by the bright fundamental rovibrational band of CO in the two R and P branches, with strong [Arvi] and relatively weaker, variable strength ejecta lines of [Siix], [Caiv], [Cav], and [Mgiv]. The NIRSpec-IFU data resolve individual ejecta knots and filaments spatially and in velocity space. The fundamental CO band in the JWST spectra reveals unique shapes of CO, showing a few tens of sinusoidal patterns of rovibrational lines with pseudocontinuum underneath, which is attributed to the high-velocity widths of CO lines. Our results with LTE modeling of CO emission indicate a temperature of ∼1080 K and provide unique insight into the correlations between dust, molecules, and highly ionized ejecta in supernovae and have strong ramifications for modeling dust formation that is led by CO cooling in the early Universe. 

Online professional development (PD) can support broader accessibility than traditional face-to- face PD. However online delivery presents challenges for characteristics of high-quality PD, such as collaborative knowledge building and community development, that have proven positive outcomes in face-to- face modes. A few comparative studies have demonstrated equivalent outcomes when PD activities have been translated from a successful face-to-face implementation to an online format. This study investigates whether an online version of PD for high school biology teachers on using computer-supported complex systems curriculum and instruction can achieve the same high impact as the face-to-face version. We describe changes in design decisions to accommodate the online mode and measure impact on teachers’ perceptions of their experiences and student outcomes. The results show positive teacher perceptions in both PD formats and roughly equal student outcomes. However, teachers articulated other benefits to online activities that indicate opportunities for improved access to high-quality PD.