93 research outputs found

    Growth of Synechococcus sp. immobilized in chitosan with different times of contact with NaOH

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    The thickness of the walls of the capsules of chitosan-immobilized Synechococcus cultures was dependent on the time of contact with NaOH and was directly related to culture growth. After an initial lag phase, probably caused by cell damage, the capsules obtained after 80 s in a 0.1 N NaOH solution showed better growth than that of free cell cultures (6.9 and 5.2 divisions in 10 days, respectively)

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    The Impact of Professional Development on Teachers’ Implementation of Formative Assessment Practices

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    Background: In order to better prepare teachers for the journey ahead of them, effective models of professional development must be implemented. Formative assessment shifts the onus of learning onto students; this necessary mindset shift from a focus on teaching to a focus on learning has the potential to transform the dynamic of urban classrooms to create self-directed learners and more insightful instructional decisions. Purpose: This study will evaluate the impact of research-based features of effective professional development on teachers’ knowledge, skills, and implementation of formative assessment practices. The proposed study will address the following research question: To what degree does a hybrid model of online- and site-based professional development affect teachers’ implementation of formative assessment practices? Methods: This study employed a convergent mixed methods approach to collect and analyze quantitative and qualitative data. The convenience sample of participants was four elementary teachers, who teach grades kindergarten through fourth. Participants were selected based on their enrollment in the course Student Agency in Learning (SAIL) and their participation as first-year participants in the Formative Assessment Project. The researcher conducted classroom observations using the Formative Assessment Rubrics, Reflection and Observation Protocol (FARROP), and catalogued participants’ professional development hours; participants completed reflections throughout the study and a pre-and posttest self-report of their implementation of formative assessment. The quantitative data allowed the researcher to analyze the improvements in formative assessment practices in teachers’ classrooms from December 2019 to March 2020, while the qualitative data augmented the findings. Data was analyzed individually and holistically to track trends, and the researcher constructed tables and graphs to show progression over the course of time in each dimension. Last, the researcher used a t-test to measure the significance of difference between the pre- and posttest self-reports. Findings: Based on exploratory analysis of teacher improvement and professional development opportunities, a diverse array of professional learning activities contributed to gains in FARROP and posttest results; however, the number of logged professional development hours did not correlate with growth. Each participant grew in their formative assessment practices from December 2019 to March 2020 in both their overall FARROP ratings, their self-selected focus dimensions, as well as their self-reports. Collaborative Culture of Learning, Success Criteria, Learning Goals, and Extended Thinking during Discourse showed the most growth overall, while Student Self-Assessment and Peer Feedback saw the smallest gains. Conclusion: The findings suggest that because of the intricate technicalities of the enactment of formative assessment dimensions, an array of opportunities that contain most or all elements of research-based elements of effective professional development is necessary to improve teachers’ implementation and practice in formative assessment

    C02 Bellini duct carcinoma of the kidney

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