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Addressing the critical STEM teachers’ shortage in the rural United States requires not only recruiting new teachers but also improving retention and teacher resiliency. This study explores contextual protective factors through the Early Career Teacher Resilience (ECTR) framework. The major objective of this study was to evaluate the impacts of the NSF Noyce Professional Learning Community (PLC) on rural STEM teacher resilience. Key components of the Noyce PLC included scholarship support, pre-service mentoring, attendance at local and regional educational events, active engagement in the program’s annual summer conference, and participation in a closed Facebook group. We developed an ECTR framework-based online instrument with 28 questions and sent it to 311 university alumni, including 44 Noyce alumni. The results suggest that the Noyce PLC has excelled in fostering collaborative learning environments, providing resources that enhance teaching and learning, accommodating new and different ways of thinking, and supporting teachers’ professional growth beyond graduation. The findings underscore the importance of integrating theoretical and practical knowledge, supporting ongoing professional learning, and building strong professional relationships. Several aspects of the Noyce PLC could be replicated in other STEM teacher preparation programs to enhance teacher resilience, effectiveness, and career development. 

Research-practitioner partnership (RPP) projects using approaches such as design-based implementation research (DBIR), seek to build organizational infrastructure to develop, implement, and sustain educational innovation [19]. Infrastructure consists of the practices and objects that support educational practice. Infrastructure constitutes human and material resources and structures that support joint work [18,29]. Although RPP literature has identified co-design as an infrastructure-building approach, to the best of our knowledge, specific techniques for managing co-design and other infrastructure building practices are still lacking [9,18,23]. Without such tools, RPP partners' varied backgrounds, workplace norms, and priorities can produce behaviors that may be normal in the context of a single organization but can impede communication, resource access, and innovation implementation in a collaborative context. The NSF-funded Computer Science Pathways RPP (CS Pathways) project's DBIR approach uses co-design of a culturally responsive middle school CS curriculum to develop infrastructure for providing high-quality CS education across three urban school districts. The curriculum focuses on developing mobile apps for social good and will be taught by teachers with varied CS experience in varied classroom contexts (e.g., civics, science). The purpose of this workshop paper is to demonstrate a technique, namely Manager Tools One-on-one meetings [15], adapted by CS Pathways partners to manage the co-design process. O3s have six features: they are frequent; scheduled; 15 to 30 minutes in duration; held with all participants working on a specified project; semi-structured; and documented by the manager or researcher. This workshop paper describes how to use O3s to engage teachers and researchers in developing collaborative infrastructure to promote shared exploration of feedback and build and sustain partnerships. 

A core hypothesis in coevolutionary theory proposes that parasites adapt to specifically infect common host genotypes. Under this hypothesis, parasites function as agents of negative frequency-dependent selection, favouring rare host genotypes. This parasite-mediated advantage of rarity is key to the idea that parasites maintain genetic variation and select for outcrossing in host populations. Here, we report the results of an experimental test of parasite adaptation to common versus rare host genotypes. We selected the bacterial parasite Serratia marcescens to kill Caenorhabdiis elegans hosts in uneven mixtures of host genotypes. To examine the effect of commonness itself, independent of host identity, each of four host genotypes was represented as common or rare in experimental host mixtures. After experimental selection, we evaluated a parasite line's change in virulence—the selected fitness trait—on its rare and common host genotypes. Our results were consistent with a slight advantage for rare host genotypes: on average, parasites lost virulence against rare genotypes but not against common genotypes. The response varied substantially, however, with distinct patterns across host genotype mixtures. These findings support the potential for parasites to impose negative frequency-dependent selection, while emphasizing that the cost of being common may vary with host genotype. 

Abstract Host–parasite interactions may often be subject to opposing evolutionary forces, which likely influence the evolutionary trajectories of both partners. Natural selection and genetic drift are two major evolutionary forces that act in host and parasite populations. Further, population size is a significant determinant of the relative strengths of these forces. In small populations, drift may undermine the persistence of beneficial alleles, potentially impeding host adaptation to parasites. Here, we investigate two questions: (a) can selection pressure for increased resistance in small, susceptible host populations overcome the effects of drift and (b) can resistance be maintained in small host populations? To answer these questions, we experimentally evolved the hostCaenorhabditis elegansagainst its bacterial parasite,Serratia marcescens, for 13 host generations. We found that strong selection favouring increased host resistance was insufficient to counteract drift in small populations, resulting in persistently high host mortality. Additionally, in small populations of resistant hosts, we found that selection for the maintenance of resistance is not always sufficient to curb the loss of resistance. We compared these results with selection in large host populations. We found that initially resistant, large host populations were able to maintain high levels of resistance. Likewise, initially susceptible, large host populations were able to gain resistance to the parasite. These results show that strong selection pressure for survival is not always sufficient to counteract drift. In consideration ofC.elegans natural population dynamics, we suggest that drift may often impede selection in nature.