805 research outputs found

    Vozes do ensino de estudantes em Nova York: a perseverança de uma experiência subtrativa do edTPA como exame de bacharel para a certificação inicial

    Get PDF
    This article explores how candidates’ experiences in multiple initial certification programs within a single School of Education evolved over the first three semesters of New York’s implementation of edTPA as a requirement for initial licensure. The data reviewed included primarily surveys and interviews of teaching candidates, framed by critical perspectives on accountability, teacher performativity, and constructivist theories on learning to teach. Results suggest candidates’ perceptions of program alignment and edTPA benefits improved while several challenges persisted. These included the lack of mentor teacher knowledge about the edTPA as well as disconnects between candidates’ edTPA scores and local program evaluations. Additionally, student teachers’ perceptions of a subtractive experience of the edTPA continued in spite of improved perceptions about the benefits of the exam and across all scoring levels, programs, and semesters. A discussion of these results considers the implication of policies that reify quality, compel performance management, and contribute to values conflict for candidates in the particularly unique developmental moment of learning to teach. These voices of student teachers, often underrepresented in the research on edTPA, urge a reconsideration of the policy on teacher performance assessments in terms of how such policies impact the experiences of those learning to teach.Este artículo explora cómo las experiencias de los candidatos en varios programas de certificación en de una Escuela de Educación se evolucionaron durante los primeros tres semestres de la implementación de edTPA en Nueva York como requisito para la licencia inicial. Los datos incluyeron encuestas y entrevistas a candidatos a la enseñanza, enmarcados por perspectivas críticas sobre la responsabilidad, la ejecución docente y las teorías constructivistas sobre el aprendizaje de la enseñanza. Los resultados sugieren que las percepciones de los candidatos sobre la alineación del programa y los beneficios de edTPA mejoraron mientras persistían varios desafíos, incluyendo la falta de conocimiento de los maestros mentores sobre el edTPA, así como las desconexiones entre los puntajes edTPA de los candidatos y las evaluaciones de los programas locales. Además, las percepciones de los maestros estudiantes sobre la experiencia sustractiva del edTPA continuaron a pesar de las percepciones favorables sobre los beneficios del examen y en todos los niveles de calificación, programas y semestres. Una discusión de estos resultados considera la implicación de las políticas que representan calidad, motivan la administración de rendimiento y contribuyen a los conflictos de valores para los candidatos en el momento de aprendizaje particularmente singular de aprender a enseñar. Estas voces de los profesores estudiantes urgen una reconsideración de política sobre las evaluaciones del rendimiento docente en términos de cómo estas polizas impactan las experiencias de aquellos que aprenden a enseñar.Este artigo explora como as experiências de candidatos em vários programas de certificação em uma Escola de Educação evoluíram durante os primeiros três semestres da implementação do edTPA em Nova York como requisito para o licenciamento inicial. Os dados incluíram pesquisas e entrevistas com candidatos para o ensino, enquadradas por perspectivas críticas sobre responsabilidade, desempenho docente e teorias construtivistas sobre o aprendizado do ensino. Os resultados sugerem que as percepções dos candidatos sobre o alinhamento do programa e os benefícios do edTPA melhoraram, enquanto vários desafios persistiram, incluindo a falta de conhecimento dos professores mentores no edTPA, bem como as desconexões entre os escores edTPA dos candidatos e as avaliações dos programas locais. Além disso, as percepções dos alunos sobre a experiência subtrativa da edTPA continuaram apesar das percepções favoráveis sobre os benefícios do exame e em todos os níveis, programas e semestres. Uma discussão sobre esses resultados considera o envolvimento de políticas que representam qualidade, motivam o gerenciamento de desempenho e contribuem para o valor dos conflitos para os candidatos no momento de aprendizagem particularmente singular de aprender a ensinar. Essas vozes de professores estudantis exigem uma reconsideração política das avaliações de desempenho dos professores em termos de como essas políticas afetam as experiências daqueles que aprendem a ensinar

    Growing Into Inquiry: Stories of Secondary School Teachers Using Inquiry for Themselves and Their Students

    Get PDF
    This study examines cases of teacher leaders in a professional development program that employed teacher inquiry to promote student inquiry. Program documents, observations, and interviews were examined to create three cases of high school science and math teachers learning to inquire in tandem. Guided by Cochran-Smith and Lytle’s (2009) “inquiry stance,” the study shows how commitment to student inquiry comes through learning gained through teacher inquiry. While conceptual understandings of teacher and student inquiry reinforced the learning of both, the parallel development of practical skills for both inquiry processes was not observed. Such conceptual growth was neither steady nor linear and characterized by some backward movement followed by significant shifts in thinking. Growth was grounded in increased experience with the process over time that deepened the teachers’ trust in their students’ ability to create their own knowledge – an understanding of the learning process that was made more visible by the program’s requirements for teachers to evaluate student inquiry as a focus of their teacher inquiry. The study confirms the need for ongoing professional development in the more complex forms of student learning embedded in newer national standards while suggesting that approaches towards professional learning must holds similar high expectations for teachers and attention to the equally complex learning required of teachers if we truly aim to create such possibilities for student learning at higher levels

    Function of N-terminal import signals in trypanosome microbodies

    Get PDF
    AbstractThe glycosomes of trypanosomes are related to eukaryoticperoxisomes. For many glycosomal and peroxisomal proteins, a C-terminal SKL-like tripeptide known as PTS-1 serves as the targeting signal. For peroxisomes, a second N-terminal signal (PTS-2) was demonstrated on rat 3-ketoacyl-CoA thiolase. Several glycosomal proteins do not bear a PTS-1. One such protein, fructose bisphosphate aldolase, has a PTS-2 homology at its N-terminus. To find out whether the PTS-2 pathway exists in trypanosomes, we expressed chloramphenicol acetyltransferase fusion proteins bearing N-terminal segments of either rat thiolase or trypanosome aldolase. The mammalian PTS-2 clearly mediated glycosomal import. The aldolase N-terminus mediated import with variable efficiency depending on the length of the appended sequence. These results provide evidence for the existence of the PTS-2 pathway in trypanosomes

    Binding of coatomer by the PEX11 C-terminus is not required for function

    Get PDF
    AbstractMicrobodies are single membrane-bound organelles found in eukaryotes from trypanosomes to man. Although they have diverse roles in metabolism, the mechanisms and molecules involved in membrane biogenesis and matrix protein import are conserved. Similarly, the basic mechanisms and structures involved in vesicular transport are similar throughout eukaryotic evolution. The PEX11 proteins are required for the division of microbodies in trypanosomes, yeast and mammals, and a role of coatomer in this process has been suggested. We show here that the binding of trypanosome, yeast and bovine coatomers to selected peptides is identical. Coatomer binds to the C-termini of trypanosome PEX11 and rat Pex11α, but not yeast Pex11p or human Pex11β. Mutations of the C-terminus of trypanosome PEX11 that eliminated coatomer binding did not affect function in yeast or trypanosomes. Thus binding of coatomer to the C-terminus of PEX11 is not required for PEX11 function

    A potential role for a novel ZC3H5 complex in regulating mRNA translation in Trypanosoma brucei

    Get PDF
    In Trypanosoma brucei and related kinetoplastids, gene expression regulation occurs mostly post-transcriptionally. Consequently, RNA-binding proteins play a critical role in the regulation of mRNA and protein abundance. Yet, the roles of many RNA-binding proteins are not understood. Our previous research identified the RNA-binding protein ZC3H5 as possibly involved in gene repression, but its role in controlling gene expression was unknown. We here show that ZC3H5 is an essential cytoplasmic RNA-binding protein: RNAi targeting ZC3H5 causes accumulation of pre-cytokinetic cells followed by rapid cell death. Affinity purification and pair-wise yeast 2-hybrid analysis suggest that ZC3H5 forms a complex with three other proteins, encoded by genes Tb927.11.4900, Tb927.8.1500 and Tb927.7.3040. RNA immunoprecipitation revealed that ZC3H5 is preferentially associated with poorly translated, low-stability mRNAs, the 5´-untranslated regions and coding regions of which are enriched in the motif (U/A)UAG(U/A). As previously found in high-throughput analyses, artificial tethering of ZC3H5 to a reporter mRNA or other complex components repressed reporter expression. However, depletion of ZC3H5 in vivo caused only very minor decreases in a few targets, marked increases in the abundances of very stable mRNAs, an increase in monosomes at the expense of large polysomes, and appearance of "halfmer" disomes containing two 80S subunits and one 40S subunit. We speculate that the ZC3H5 complex might be implicated in quality control during the translation of sub-optimal open reading frames.Fil: Bajak, Kathrin. Universität Heidelberg; AlemaniaFil: Leiss, Kevin. Universität Heidelberg; AlemaniaFil: Clayton, Christine. Universität Heidelberg; AlemaniaFil: Erben, Esteban Daniel. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Biotecnológicas; Argentin

    Transcriptomes of newly-isolated Trypanosoma brucei rhodesiense reveal hundreds of mRNAs that are co-regulated with stumpy-form markers

    Get PDF
    Background: During natural Trypanosoma brucei infections, the parasites differentiate spontaneously into a non-dividing “stumpy” form when a certain level of parasitaemia is attained. This form is metabolically adapted for rapid further differentiation into procyclic forms upon uptake by Tsetse flies. Results: We describe here four central Ugandan isolates of Trypanosoma brucei rhodesiense that have undergone only three rodent passages since isolation from human patients. As expected, SNP analysis shows that these isolates are more closely related to each other than to the commonly used strains Lister 427, Antat1.1, and TREU927. TREU927 generally has smaller copy numbers of repeated genes than the other strains, while Lister 427 trypanosomes with a 30-year history of in vitro culture and cloning have more histone genes than the other isolates. The recently isolated trypanosomes were grown in rats, and their transcriptomes characterised. In comparison with cultured procyclic and bloodstream forms, there were increases in mRNAs encoding the stumpy-form markers ESAG9 and PIP39, with coordinated alterations in the levels of over 600 additional mRNAs. Numerous mRNAs encoding proteins of no known function were either increased or decreased. The products of the mRNAs that were increased in parallel with PIP39 included not only enzymes of procyclic-form metabolism, but also components of the translational and RNA control machineries. Many of the mRNAs that were decreased in cells with elevated PIP39 reflected reduced cell division. Conclusions: These transcriptomes suggest new avenues for research into the regulation of trypanosome differentiation

    Insurance Coverage Policies for Pharmacogenomic and Multi-Gene Testing for Cancer

    Get PDF
    Abstract: Insurance coverage policies are a major determinant of patient access to genomic tests. The objective of this study was to examine differences in coverage policies for guideline-recommended pharmacogenomic tests that inform cancer treatment. We analyzed coverage policies from eight Medicare contractors and 10 private payers for 23 biomarkers (e.g., HER2 and EGFR) and multi-gene tests. We extracted policy coverage and criteria, prior authorization requirements, and an evidence basis for coverage. We reviewed professional society guidelines and their recommendations for use of pharmacogenomic tests. Coverage for KRAS, EGFR, and BRAF tests were common across Medicare contractors and private payers, but few policies covered PML/RARA, CD25, or G6PD. Twelve payers cover at least one multi-gene test for nonsmall cell lung cancer, citing emerging clinical recommendations. Coverage policies for single and multi-gene tests for cancer treatments are relatively consistent among Medicare contractors despite the lack of national coverage determinations. In contrast, coverage for these tests varied across private payers. Patient access to tests is governed by prior authorization among eight private payers. Substantial variations in how payers address guideline-recommended pharmacogenomic tests and the common use of prior authorization underscore the need for additional studies of the effects of coverage variation on cancer care and patient outcomes

    Transcriptome analysis of differentiating trypanosomes reveals the existence of multiple post-transcriptional regulons

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Trypanosome gene expression is regulated almost exclusively at the post-transcriptional level, with mRNA degradation playing a decisive role. When trypanosomes are transferred from the blood of a mammal to the midgut of a Tsetse fly, they transform to procyclic forms: gene expression is reprogrammed, changing the cell surface and switching the mode of energy metabolism. Within the blood, trypanosomes can pre-adapt for Tsetse transmission, becoming growth-arrested stumpy forms. We describe here the transitions in gene expression that occur during differentiation of <it>in-vitro </it>cultured bloodstream forms to procyclic forms.</p> <p>Results</p> <p>Some mRNAs showed changes within 30 min of <it>cis-</it>aconitate addition, whereas others responded 12-24 hours later. For the first 12 h after addition of <it>cis</it>-aconitate, cells accumulated at the G1 phase of the cell cycle, and showed decreases in mRNAs required for proliferation, mimicking the changes seen in stumpy forms: many mRNAs needed for ribosomal and flagellar biogenesis showed striking co-regulation. Other mRNAs encoding components of signal transduction pathways and potential regulators were specifically induced only during differentiation. Messenger RNAs encoding proteins required for individual metabolic pathways were often co-regulated.</p> <p>Conclusion</p> <p>Trypanosome genes form post-transcriptional regulons in which mRNAs with functions in particular pathways, or encoding components of protein complexes, show almost identical patterns of regulation.</p

    Being in Tension: Faculty Explorations of the Meaning of Social Justice in Teacher Education

    Get PDF
    This study explores faculty perspectives of social justice in teacher education within one New York institution with a social justice focus. Grounded in the institution’s self-study process for accreditation, the researchers were a part of a team that collected data from structured interviews, including a card sort, of 42 full time teacher educators across 16 programs in the institution. Informed by sociocultural theories (Vygotsky, 1978, Wertsch, 1991), a content analysis revealed the language selected by faculty as well as their meaning-making process and describes how individuals contextualized those meanings. Findings demonstrated a range of meanings and lack of a shared understanding about social justice. Even where apparent consensus existed around particular terminology, the content analysis revealed that individual meanings were deeply contextualized within disciplines and, thereby, were quite distinct. We raise questions regarding how to use dialogue as a meaning making process, the possibilities for a range of meanings, and the significance of contextualizing social justice. The study suggests that significant tensions remain but that “being in tension” is a critical position and potentially informative to faculty who might consider using a framework that invites more diverse perspective rather than embrace a unitary meaning of the term
    corecore