32 research outputs found

    Place-based curriculum in the eighth grade English language arts classroom

    Get PDF
    Master's Project (M.Ed.) University of Alaska Fairbanks, 2015In this project, I am investigating the role of place-based education (PBE) in the eighth grade English Language Arts (ELA) classroom and creating a place-based curriculum to use in this class. While PBE has many different definitions and connotations, I define it here as a type of education that takes advantage of the local opportunities to learn in a community and place as a basis for an educational experience. PBE engages student learning by making connections to their community through their work, identifying how their classwork is connected to life, and providing students with an authentic audience for their products beyond the school setting. ELA is an overlooked content within PBE because it is often aligned with courses in science, social studies, or outdoors content. In reality, because ELA is a class of skills and knowledge and not content memorization, it meshes perfectly with PBE. Therefore, the focus of this project is an informational writing curriculum based on PBE methodologies embedded in ELA Alaska Standards at the eighth grade level

    BgaA acts as an adhesin to mediate attachment of some pneumococcal strains to human epithelial cells

    Get PDF
    Streptococcus pneumoniae colonization of the respiratory tract is an essential precursor for pneumococcal disease. To colonize efficiently, bacteria must adhere to the epithelial-cell surface. S. pneumoniae possesses surface-associated exoglycosidases that are capable of sequentially deglycosylating human glycans. Two exoglycosidases, neuraminidase (NanA) and β-galactosidase (BgaA), have previously been shown to contribute to S. pneumoniae adherence to human epithelial cells, as deletion of either of these genes results in reduced adherence. It has been suggested that these enzymes may modulate adherence by cleaving sugars to reveal a receptor on host cells. Pretreatment of epithelial cells with exogenous neuraminidase restores the adherence of a nanA mutant, whereas pretreatment with β-galactosidase does not restore the adherence of a bgaA mutant. These data suggest that BgaA may not function to reveal a receptor, and implicate an alternative role for BgaA in adherence. Here we demonstrate that β-galactosidase activity is not required for BgaA-mediated adherence. Addition of recombinant BgaA (rBgaA) to adherence assays and pretreatment of epithelial cells with rBgaA both significantly reduced the level of adherence of the parental strain, but not the BgaA mutant. One possible explanation of these data is that BgaA is acting as an adhesin and that rBgaA is binding to the receptor, preventing bacterial binding. A bead-binding assay demonstrated that BgaA can bind directly to human epithelial cells, supporting the hypothesis that BgaA is an adhesin. Preliminary characterization of the epithelial-cell receptor suggests that it is a glycan in the context of a glycosphingolipid. To further establish the relevance of this adherence mechanism, we demonstrated that BgaA-mediated adherence contributed to adherence of a recent clinical isolate to primary human epithelial cells. Together, these data suggest a novel role for BgaA as an adhesin and suggest that this mechanism could contribute to adherence of at least some pneumococcal strains in vivo

    Clinical, neuroradiological, and molecular characterization of mitochondrial threonyl-tRNA-synthetase (TARS2)-related disorder

    Get PDF
    PURPOSE: Biallelic variants in TARS2, encoding the mitochondrial threonyl-tRNA-synthetase, have been reported in a small group of individuals displaying a neurodevelopmental phenotype, but with limited neuroradiological data and insufficient evidence for causality of the variants. METHODS: Exome or genome sequencing was carried out in 15 families. Clinical and neuroradiological evaluation was performed for all affected individuals, including review of 10 previously reported individuals. The pathogenicity of TARS2 variants was evaluated using in vitro assays, and a zebrafish model. RESULTS: We report 18 new individuals harboring biallelic TARS2 variants. Phenotypically, these individuals show developmental delay/intellectual disability, regression, cerebellar and cerebral atrophy, basal ganglia signal alterations, hypotonia, cerebellar signs and increased blood lactate. In vitro studies showed that variants within the TARS2301-381 region had decreased binding to Rag GTPases, likely impairing mTORC1 activity. The zebrafish model recapitulated key features of the human phenotype and unraveled dysregulation of downstream targets of mTORC1 signaling. Functional testing of the variants confirmed the pathogenicity in a zebrafish model. CONCLUSION: We define the clinico-radiological spectrum of TARS2-related mitochondrial disease, unveil the likely involvement of the mTORC1 signaling pathway as a distinct molecular mechanism, and establish a TARS2 zebrafish model as an important tool to study variant pathogenicity

    The Beaker phenomenon and the genomic transformation of northwest Europe

    Get PDF
    From around 2750 to 2500 bc, Bell Beaker pottery became widespread across western and central Europe, before it disappeared between 2200 and 1800 bc. The forces that propelled its expansion are a matter of long-standing debate, and there is support for both cultural diffusion and migration having a role in this process. Here we present genome-wide data from 400 Neolithic, Copper Age and Bronze Age Europeans, including 226 individuals associated with Beaker-complex artefacts. We detected limited genetic affinity between Beaker-complex-associated individuals from Iberia and central Europe, and thus exclude migration as an important mechanism of spread between these two regions. However, migration had a key role in the further dissemination of the Beaker complex. We document this phenomenon most clearly in Britain, where the spread of the Beaker complex introduced high levels of steppe-related ancestry and was associated with the replacement of approximately 90% of Britain’s gene pool within a few hundred years, continuing the east-to-west expansion that had brought steppe-related ancestry into central and northern Europe over the previous centuries

    Do You See What I See? Actor and Partner Attachment Shape Biased Perceptions of Partners

    No full text
    The present research examined how actor and partner attachment insecurity relates to biases in perceptions of partners’ core relationship-relevant constructs. Across three dyadic studies (Ncouples = 333, Nindividuals = 666), we examined attachment anxiety and avoidance as predictors of over- or underestimation of partners’ relationship satisfaction, commitment, and responsiveness, using partners’ own reports as the reference point for evaluating bias. Actors higher in avoidance and actors with partners higher in avoidance perceived their partners to be less satisfied and committed. In addition, actors higher in avoidance and actors higher in anxiety displayed a pessimistic bias, perceiving their partners to be less satisfied and committed than their partners reported being. Finally, actors with partners higher in avoidance displayed an optimistic bias, perceiving their partners to be more satisfied and committed than their partners reported being. Results underscore the importance of adopting a dyadic perspective on perceptual biases in romantic relationships
    corecore