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The timing of sea ice retreat and advance in Arctic coastal waters varies substantially from year to year. Various activities, ranging from marine transport to the use of sea ice as a platform for industrial activity or winter travel, are af- fected by variations in the timing of breakup and freeze-up, resulting in a need for indicators to document the regional and temporal variations in coastal areas. The primary objec- tive of this study is to use locally based metrics to construct indicators of breakup and freeze-up in the Arctic and subarc- tic coastal environment. The indicators developed here are based on daily sea ice concentrations derived from satellite passive-microwave measurements. The “day of year” indica- tors are designed to optimize value for users while building on past studies characterizing breakup and freeze-up dates in the open pack ice. Relative to indicators for broader adja- cent seas, the coastal indicators generally show later breakup at sites known to have landfast ice. The coastal indicators also show earlier freeze-up at some sites in comparison with freeze-up for broader offshore regions, likely tied to ear- lier freezing of shallow-water regions and areas affected by freshwater input from nearby streams and rivers. Amore »factor analysis performed to synthesize the local indicator varia- tions shows that the local breakup and freeze-up indicators have greater spatial variability than corresponding metrics based on regional ice coverage. However, the trends towards earlier breakup and later freeze-up are unmistakable over the post-1979 period in the synthesized metrics of coastal breakup and freeze-up and the corresponding regional ice coverage. The findings imply that locally defined indicators can serve as key links between pan-Arctic or global indica- tors such as sea ice extent or volume and local uses of sea ice, with the potential to inform community-scale adaptation and response.« less

COVID-19 has altered the landscape of teaching and learning. For those in in-service teacher education, workshops have been suspended causing programs to adapt their professional development to a virtual space to avoid indefinite postponement or cancellation. This paradigm shift in the way we conduct learning experiences creates several logistical and pedagogical challenges but also presents an important opportunity to conduct research about how learning happens in these new environments. This paper describes the approach we took to conduct research in a series of virtual workshops aimed at teaching rural elementary teachers about engineering practices and how to teach a unit from an engineering curriculum. Our work explores how engineering concepts and practices are socially constructed through interactions with teachers, students, and artifacts. This approach, called interactional ethnography has been used by the authors and others to learn about engineering teaching and learning in precollege classrooms. The approach relies on collecting data during instruction, such as video and audio recordings, interviews, and artifacts such as journal entries and photos of physical designs. Findings are triangulated by analyzing these data sources. This methodology was going to be applied in an in-person engineering education workshop for rural elementary teachers, however the pandemic forcedmore »us to conduct the workshops remotely. Teachers, working in pairs, were sent workshop supplies, and worked together during the training series that took place over Zoom over four days for four hours each session. The paper describes how we collected video and audio of teachers and the facilitators both in whole group and in breakout rooms. Class materials and submissions of photos and evaluations were managed using Google Classroom. Teachers took photos of their work and scanned written materials and submitted them all by email. Slide decks were shared by the users and their group responses were collected in real time. Workshop evaluations were collected after each meeting using Google Forms. Evaluation data suggest that the teachers were engaged by the experience, learned significantly about engineering concepts and the knowledge-producing practices of engineers, and feel confident about applying engineering activities in their classrooms. This methodology should be of interest to the membership for three distinct reasons. First, remote instruction is a reality in the near-term but will likely persist in some form. Although many of us prefer to teach in person, remote learning allows us to reach many more participants, including those living in remote and rural areas who cannot easily attend in-person sessions with engineering educators, so it benefits the field to learn how to teach effectively in this way. Second, it describes an emerging approach to engineering education research. Interactional ethnography has been applied in precollege classrooms, but this paper demonstrates how it can also be used in teacher professional development contexts. Third, based on our application of interactional ethnography to an education setting, readers will learn specifically about how to use online collaborative software and how to collect and organize data sources for research purposes.« less

Karyotypic diversity is critical to catalyzing change in the evolution of all plants. By resulting in meiotic incompatibility among sets of homologous chromosomes, polyploidy and aneuploidy may facilitate reproductive isolation and the potential for speciation. Across plants, karyotypic variants in the form of allopolyploids receive greater taxonomic attention relative to autopolyploids and aneuploids. In particular, the prevalence and significance of autopolyploidy and aneuploidy in bryophytes is little understood. Using Fritsch’s 1991 compendium of bryophyte karyotypes with augmentation from karyological studies published since, we have quantified the prevalence of karyotypic variants among ~1500 extant morphological species of mosses. We assessed the phylogenetic distribution of karyological data, the frequency of autopolyploidy and aneuploidy, and the methodological correlates with karyotypic diversity. At least two ploidy levels were recorded from 17% of species potentially increasing current taxonomic diversity of mosses to over 15,000 species. We find that for a given species, the number of unique karyotypes recorded is correlated with the number of populations sampled. The evidence suggests that cytological diversity likely underlies yet undescribed species diversity in mosses, and that intensive karyological sampling is a needed tool for its discovery.

The detection of variations of fundamental constants of the Standard Model would provide us with compelling evidence of new physics, and could lift the veil on the nature of dark matter and dark energy. In this work, we discuss how a network of atomic and molecular clocks can be used to look for such variations with unprecedented sensitivity over a wide range of time scales. This is precisely the goal of the recently launched QSNET project: A network of clocks for measuring the stability of fundamental constants. QSNET will include state-of-the-art atomic clocks, but will also develop next-generation molecular and highly charged ion clocks with enhanced sensitivity to variations of fundamental constants. We describe the technological and scientific aims of QSNET and evaluate its expected performance. We show that in the range of parameters probed by QSNET, either we will discover new physics, or we will impose new constraints on violations of fundamental symmetries and a range of theories beyond the Standard Model, including dark matter and dark energy models.

Projects rarely go according to plan, but this is especially true of those that involve multiple institutions and have a significant degree of complexity associated with them. This work relates the experiences an Advanced Technological Education (ATE) project around high value manufacturing. The project was a collaboration with a Texas A&M University and Houston Community College. The project comprised three main aspects: 1) the development of a certificate program in high value manufacturing; 2) offering professional development to working professionals in the area of high value manufacturing; and 3) educating teachers about advanced manufacturing with a goal of recruiting their students into manufacturing careers. This work describes the lessons learned through each of the project aspects. The design of the High Value Manufacturing Certificate Program required close collaboration between both institutions. The issues that arose during this development process included personnel turnover, approval timelines and processes, and agreement on the course content. The authors will relay how they navigated these issues to get the program created and approved. The creation of the professional development program did not involve the community college directly, but was very dependent on recruiting participants. This recruitment proved to be more difficult than the project teammore »expected. The targeting of the professional development program and the development of the curriculum will be discussed. The authors will also highlight the delivery changes they implemented over the two years of the offerings based on participant feedback. The final aspect of the project is the teacher experience with advanced manufacturing. Hosting teachings and determining what content and activities they experience is a somewhat daunting task. The use of an existing University Program and the selection of collaborating faculty will be discussed. Overall, the lessons learned from this project can be an opportunity for new ATE principal investigators (PIs) to learn from the authors’ experiences. It can also help potential ATE PIs craft more realistic and practical proposals.« less