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Despite the widespread exploration and availability of parcellations for the functional connectome, parcellations designed for the structural connectome are comparatively limited. Current research suggests that there may be no single “correct” parcellation and that the human brain is intrinsically a multiresolution entity. In this work, we propose the Continuous Structural Connectivitity-based, Nested (CoCoNest) family of parcellations—a fully data-driven, multiresolution family of parcellations derived from structural connectome data. The CoCoNest family is created using agglomerative (bottom-up) clustering and error-complexity pruning, which strikes a balance between the complexity of each parcellation and how well it preserves patterns in vertex-level, high-resolution connectivity data. We draw on a comprehensive battery of internal and external evaluation metrics to show that the CoCoNest family is competitive with or outperforms widely used parcellations in the literature. Additionally, we show how the CoCoNest family can serve as an exploratory tool for researchers to investigate the multiresolution organization of the structural connectome. 

Despite the widespread exploration and availability of parcellations for the functional connectome, parcellations designed for the structural connectome are comparatively limited. Current research suggests that there may be no single “correct” parcellation and that the human brain is intrinsically a multiresolution entity. In this work, we propose the Continuous Structural Connectivitity-based, Nested (CoCoNest) family of parcellations—a fully datadriven, multiresolution family of parcellations derived from structural connectome data. The CoCoNest family is created using agglomerative (bottom-up) clustering and error-complexity pruning, which strikes a balance between the complexity of each parcellation and how well it preserves patterns in vertex-level, high-resolution connectivity data. We draw on a comprehensive battery of internal and external evaluation metrics to show that the CoCoNest family is competitive with or outperforms widely used parcellations in the literature. Additionally, we show how the CoCoNest family can serve as an exploratory tool for researchers to investigate the multiresolution organization of the structural connectome 

Abstract The meltwater streams of the McMurdo Dry Valleys are hot spots of biological diversity in the climate-sensitive polar desert landscape. Microbial mats, largely comprised of cyanobacteria, dominate the streams which flow for a brief window of time (~10 weeks) over the austral summer. These communities, critical to nutrient and carbon cycling, display previously uncharacterized patterns of rapid destabilization and recovery upon exposure to variable and physiologically detrimental conditions. Here, we characterize changes in biodiversity, transcriptional responses and activity of microbial mats in response to hydrological disturbance over spatiotemporal gradients. While diverse metabolic strategies persist between marginal mats and main channel mats, data collected from 4 time points during the austral summer revealed a homogenization of the mat communities during the mid-season peak meltwater flow, directly influencing the biogeochemical roles of this stream ecosystem. Gene expression pattern analyses identified strong functional sensitivities of nitrogen-fixing marginal mats to changes in hydrological activities. Stress response markers detailed the environmental challenges of each microhabitat and the molecular mechanisms underpinning survival in a polar desert ecosystem at the forefront of climate change. At mid and end points in the flow cycle, mobile genetic elements were upregulated across all mat types indicating high degrees of genome evolvability and transcriptional synchronies. Additionally, we identified novel antifreeze activity in the stream microbial mats indicating the presence of ice-binding proteins (IBPs). Cumulatively, these data provide a new view of active intra-stream diversity, biotic interactions and alterations in ecosystem function over a high-flow hydrological regime. 

Abstract Metal-organic decomposition epitaxy is an economical wet-chemical approach suitable to synthesize high-quality low-spin-damping films for resonator and oscillator applications. This work reports the temperature dependence of ferromagnetic resonances and associated structural and magnetic quantities of yttrium iron garnet nanofilms that coincide with single-crystal values. Despite imperfections originating from wet-chemical deposition and spin coating, the quality factor for out-of-plane and in-plane resonances approaches 600 and 1000, respectively, at room temperature and 40 GHz. These values increase with temperature and are 100 times larger than those offered by commercial devices based on complementary metal-oxide semiconductor voltage-controlled oscillators at comparable production costs. 

Before the shelter-in-place orders began, Biotech Partners (BP) was already engaged in contingency plan- ning with its school and industry partners in an effort to mitigate potential disruptions caused by the looming health crisis. For 25 years prior, BP had successfully mentored and prepared underrepresented high school students to complete profes- sional internships at diverse STEM institutions. Often working in a laboratory or pharmaceutical manufacturing setting, the internships allowed students to apply bioscience, biotechnology, and professional career skills developed in school within the context of a professional workplace. The promise of paid internships in a cutting-edge industry creates an incentive to motivate and maximize student learning in rigorous academic training and workforce preparation. As the COVID-19 pandemic unfolded, most industry sites cancelled their 2020 participation, putting the summer internships in jeopardy. BP rapidly shifted. Collaborating with new and longstanding industry partners, the internship program was modified from in-person to remote work and learning environments. This case study examines the pedagogical challenges and opportunities of conducting remote STEM internships amid a global pandemic. This paper illuminates the role of industry partnerships, student outreach, personalized mentoring, and wrap-around support services to broaden students’ awareness of, interest in, and preparation for careers in the STEM workforce. 

Through a qualitative case study approach, this study examines the pedagogical context of training and mentoring students to undertake STEM internships. This paper explores the learning conditions and outcomes of Biotech Partners (BP), a nonprofit organization working at the intersections of bioscience/biotechnology workforce education in collaboration with public high schools and professional experts and organizations in a range of STEM industries. Incorporating multiple stakeholder perspectives (youth, industry partners, mentors, biotech educators), the study unpacks the nature and impacts of these cross-sector partnerships: In what roles and in what ways do bioscience educators and business and industry workforce members motivate students from diverse underrepresented populations to become aware of, interested in, and prepared for careers in the STEM workforce? 

K–12 schools across the United States have been challenged to make programmatic shifts to meet the needs of youth and their families during the COVID-19 pandemic. Due to both structure and existing connections to youth and families, many out-of-school learning (OSL) programs, including Pre-College STEM Programs (PCSPs), are nimbler and have the ability to be more responsive. The STEM PUSH Network (a National Science Foundation INCLUDES Alliance; https://stempushnetwork.org)—which brings together PCSPs as part of a national collaborative of programs and citywide STEM Ecosystems focused on program improvement and college admissions—revealed some of the ways programs have adjusted during COVID- 19, as well as the ways systematic cross-program collaboration can enhance this work. 

Abstract Phytoplankton and associated microbial communities provide organic carbon to oceanic food webs and drive ecosystem dynamics. However, capturing those dynamics is challenging. Here, an in situ, semi-Lagrangian, robotic sampler profiled pelagic microbes at 4 h intervals over ~2.6 days in North Pacific high-nutrient, low-chlorophyll waters. We report on the community structure and transcriptional dynamics of microbes in an operationally large size class (>5 μm) predominantly populated by dinoflagellates, ciliates, haptophytes, pelagophytes, diatoms, cyanobacteria (chiefly Synechococcus), prasinophytes (chiefly Ostreococcus), fungi, archaea, and proteobacteria. Apart from fungi and archaea, all groups exhibited 24-h periodicity in some transcripts, but larger portions of the transcriptome oscillated in phototrophs. Periodic photosynthesis-related transcripts exhibited a temporal cascade across the morning hours, conserved across diverse phototrophic lineages. Pronounced silica:nitrate drawdown, a high flavodoxin to ferredoxin transcript ratio, and elevated expression of other Fe-stress markers indicated Fe-limitation. Fe-stress markers peaked during a photoperiodically adaptive time window that could modulate phytoplankton response to seasonal Fe-limitation. Remarkably, we observed viruses that infect the majority of abundant taxa, often with total transcriptional activity synchronized with putative hosts. Taken together, these data reveal a microbial plankton community that is shaped by recycled production and tightly controlled by Fe-limitation and viral activity.