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Some computing education researchers have shifted focus from broadening participation to justice-centered computing education (JCCE). JCCE teaches computing through its social-political implications, empowering students to create more just futures. While prior research theorizes and explores its classroom application, we know little about the collaborative processes instructors use to design and adapt curricula for such learning. We engaged in a 3-month curriculum co-design project as part of a research-practice partnership between a CS education researcher and an after-school STEAM instructor. Through duo-ethnography, we analyzed our curriculum design process. We highlight key emerging challenges and how we resolved them through the design process. Our findings focus on balancing students' technical proficiency with justice-centered pedagogy, showing that justice-centered curriculum design requires educators' ongoing content learning, reflection on positionality, and adaptability to students' needs, including those with disabilities. These findings bridge the theoretical discussion of justice-centered computing with the practical realities of curriculum design. 

Abstract Gene syntax—the order and arrangement of genes and their regulatory elements—shapes the dynamic coordination of both natural and synthetic gene circuits. Transcription at one locus profoundly impacts the transcription of nearby adjacent genes, but the molecular basis of this effect remains poorly understood. Here, using integrated reporter circuits in human cells, we show that the reciprocal effects of transcription and DNA supercoiling, which we term supercoiling-mediated feedback, regulates expression of adjacent genes in a syntax-specific manner. Using a suite of chromatin state assays, we measure syntax-and induction-dependent formation of chromatin structures in human induced pluripotent stem cells. Applying syntax as a design parameter and without altering sequence or copy number, we built compact gene circuits, tuning the expression mean, noise, and stoichiometry across diverse delivery methods and cell types. Integrating supercoiling-mediated feedback into models of gene regulation will expand our understanding of native systems and enhance the design of synthetic gene circuits. 

Habitat fragmentation can negatively impact wildlife populations by simplification of ecological interactions, but little is known about how these impacts extend to host-associated symbiotic communities. The symbiotic communities of amphibians play important roles in anti-pathogen defences, particularly against the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd). In this study, we analyse the role of macroparasitic helminth communities in concert with microbial communities in defending the host against Bd infection within the context of forest fragmentation. We found that skin microbial and helminth communities are disrupted at fragmented habitats, while gut microbiomes appear more resilient to environmental change. We also detected potential protective roles of helminth diversity and anti-pathogen microbial function in limiting Bd infection. Microbial network analysis revealed strong patterns of structure in both skin and gut communities, with helminths playing central roles in these networks. We reveal consistent roles of microbial and helminth diversity in driving host–pathogen interactions and the potential implications of fragmentation on host fitness. 

Teachers grow from sharing their practice and receiving feedback, yet it can be difficult for teachers to welcome others into their classrooms without feeling judged. Observers need to enter teachers’ classrooms projecting respect and value for the challenging work of teaching. In this article, we share an approach to visiting classrooms, called Affirming Learning Walks, that differs in comparison to more typical learning walks, instructional rounds, or classroom observations. Affirming learning walks are hosted by teachers or administrators, conducted with other teachers, designed around eight practices known to support student achievement, and focused only on those productive practices that are present rather than on the absence of practices or areas for improvement. This approach provides an opportunity to value many of a teacher’s practices that are productive and encourages teachers to engage in more of the productive practices because they are highlighted and celebrated. 

The amphibian skin microbiome is an important component of anti-pathogen defense, but the impact of environmental change on the link between microbiome composition and host stress remains unclear. In this study, we used radiotelemetry and host translocation to track microbiome composition and function, pathogen infection, and host stress over time across natural movement paths for the forest-associated treefrog, Boana faber. We found a negative correlation between cortisol levels and putative microbiome function for frogs translocated to forest fragments, indicating strong integration of host stress response and anti-pathogen potential of the microbiome. Additionally, we observed a capacity for resilience (resistance to structural change and functional loss) in the amphibian skin microbiome, with maintenance of putative pathogen-inhibitory function despite major temporal shifts in microbiome composition. Although microbiome community composition did not return to baseline during the study period, the rate of microbiome change indicated that forest fragmentation had more pronounced effects on microbiome composition than translocation alone. Our findings reveal associations between stress hormones and host microbiome defenses, with implications for resilience of amphibians and their associated microbes facing accelerated tropical deforestation. 

National rates of gun violence have risen during the COVID-19 pandemic. There are many contributing factors to this increase, including the compounding consequences of social isolation, unstable housing, decreased economic stability, and ineffective and violent policing of communities of color. The effects of these factors are exacerbated by the pandemic's impact on the provision and availability of psychosocial services for individuals in marginalized communities, particularly those who have been violently injured. Hospital-based violence intervention programs (HVIPs) have been identified as a crucial intervention strategy in reducing repeat violent injury. The ongoing COVID-19 pandemic has engendered, significant barriers in HVIPs' attempts to assist program participants in achieving their health-related and social goals. This research offers insight into the complexities of providing social services during the convergence of two public health crises—COVID-19 and gun violence—at the HVIPs associated with the two busiest trauma centers in the state of Maryland. In considering the effects of inadequate financial support and resources, issues with staffing, and the shift to virtual programming due to restrictions on in-person care, we suggest possible changes to violence prevention programming to increase the quality of care provided to participants in a manner reflective of their unique structural positions. 

Abstract Batrachochytrium salamandrivorans ( Bsal ) is a fungal pathogen of amphibians that is emerging in Europe and could be introduced to North America through international trade or other pathways. To evaluate the risk of Bsal invasion to amphibian biodiversity, we performed dose-response experiments on 35 North American species from 10 families, including larvae from five species. We discovered that Bsal caused infection in 74% and mortality in 35% of species tested. Both salamanders and frogs became infected and developed Bsal chytridiomycosis. Based on our host susceptibility results, environmental suitability conditions for Bsal , and geographic ranges of salamanders in the United States, predicted biodiversity loss is expected to be greatest in the Appalachian Region and along the West Coast. Indices of infection and disease susceptibility suggest that North American amphibian species span a spectrum of vulnerability to Bsal chytridiomycosis and most amphibian communities will include an assemblage of resistant, carrier, and amplification species. Predicted salamander losses could exceed 80 species in the United States and 140 species in North America. 

Abstract Engineered signaling networks can impart cells with new functionalities useful for directing differentiation and actuating cellular therapies. For such applications, the engineered networks must be tunable, precisely regulate target gene expression, and be robust to perturbations within the complex context of mammalian cells. Here, we use bacterial two-component signaling proteins to develop synthetic phosphoregulation devices that exhibit these properties in mammalian cells. First, we engineer a synthetic covalent modification cycle based on kinase and phosphatase proteins derived from the bifunctional histidine kinase EnvZ, enabling analog tuning of gene expression via its response regulator OmpR. By regulating phosphatase expression with endogenous miRNAs, we demonstrate cell-type specific signaling responses and a new strategy for accurate cell type classification. Finally, we implement a tunable negative feedback controller via a small molecule-stabilized phosphatase, reducing output expression variance and mitigating the context-dependent effects of off-target regulation and resource competition. Our work lays the foundation for establishing tunable, precise, and robust control over cell behavior with synthetic signaling networks.