899 research outputs found

    Pennies and Eggs: Initiation Into Inquiry Learning for Pre-Service Elementary Education Teachers

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    Two labs incorporating the Science Writing Heuristic are described that introduce scientific inquiry in a course for preservice students majoring in elementary education. One lab adapts a previously described discovery learning opportunity involving the change in composition and mass of pennies in 1982. The other involves the use of flotation methods to separate hard-boiled and uncooked eggs based on density. Evidence for student engagement with the method is presented, along with analysis of persistent problems with the concept of density revealed by students’ writing about their understandings

    <書評>Anne L. Alstott, "A New Deal For Old Age", Harvard University Press, 2016

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    社会学 : 書

    Adaptive laboratory evolution of a genome-reduced Escherichia coli.

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    Synthetic biology aims to design and construct bacterial genomes harboring the minimum number of genes required for self-replicable life. However, the genome-reduced bacteria often show impaired growth under laboratory conditions that cannot be understood based on the removed genes. The unexpected phenotypes highlight our limited understanding of bacterial genomes. Here, we deploy adaptive laboratory evolution (ALE) to re-optimize growth performance of a genome-reduced strain. The basis for suboptimal growth is the imbalanced metabolism that is rewired during ALE. The metabolic rewiring is globally orchestrated by mutations in rpoD altering promoter binding of RNA polymerase. Lastly, the evolved strain has no translational buffering capacity, enabling effective translation of abundant mRNAs. Multi-omic analysis of the evolved strain reveals transcriptome- and translatome-wide remodeling that orchestrate metabolism and growth. These results reveal that failure of prediction may not be associated with understanding individual genes, but rather from insufficient understanding of the strain's systems biology

    Perinatal hypoxic-ischemic encephalopathy and neuroprotective peptide therapies: A case for cationic arginine-rich peptides (CARPs)

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    Perinatal hypoxic-ischemic encephalopathy (HIE) is the leading cause of mortality and morbidity in neonates, with survivors suffering significant neurological sequelae including cerebral palsy, epilepsy, intellectual disability and autism spectrum disorders. While hypothermia is used clinically to reduce neurological injury following HIE, it is only used for term infants (\u3e36 weeks gestation) in tertiary hospitals and improves outcomes in only 30% of patients. For these reasons, a more effective and easily administrable pharmacological therapeutic agent, that can be used in combination with hypothermia or alone when hypothermia cannot be applied, is urgently needed to treat pre-term (_36 weeks gestation) and term infants suffering HIE. Several recent studies have demonstrated that cationic arginine-rich peptides (CARPs), which include many cell-penetrating peptides [CPPs; e.g., transactivator of transcription (TAT) and poly-arginine-9 (R9; 9-mer of arginine)], possess intrinsic neuroprotective properties. For example, we have demonstrated that poly-arginine-18 (R18; 18-mer of arginine) and its D-enantiomer (R18D) are neuroprotective in vitro following neuronal excitotoxicity, and in vivo following perinatal hypoxia-ischemia (HI). In this paper, we review studies that have used CARPs and other peptides, including putative neuroprotective peptides fused to TAT, in animal models of perinatal HIE. We critically evaluate the evidence that supports our hypothesis that CARP neuroprotection is mediated by peptide arginine content and positive charge and that CARPs represent a novel potential therapeutic for HIE

    Fostering Preservice Teacher Identity in Science through a Student-Selected Project

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    This article addresses the problem of authentic student engagement in the science classroom by incorporating a semester long research and writing assignment that enables students to investigate scientific topics related to strong personal, career, or health interests
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