65 research outputs found

    An investigation of the role of physical manipulatives in the teaching and learning of measurement in Grade 8 : a case study using surface area and volume

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    The purpose of this study is to investigate the role of physical manipulatives in the teaching and learning of measurement in Grade 8. The study focuses on how the use of physical manipulatives promotes learners' mathematical proficiency in relation to the five strands of Kilpatrick, Swafford and Findell (2001). The basis of the research is a case study in the interpretive paradigm involving 18 out of a cohort of 270 Grade 8 learners in the school where I teach. The data was collected using a range of methods including: (i) baseline assessment tasks, first piloted using 7 Grade 8 learners and then given to the target group; (ii) an intervention programme with intervention tasks; (iii) a post-intervention task; (iv) observations during the intervention; and (v) individual interviews. The results of the baseline assessment and the post-intervention tasks were analysed both quantitatively and qualitatively. My research findings indicate an overall improvement of the performance after learners engaged in using physical manipulatives. The average mark of the learners in the baseline assessment task was 23% and after the intervention programme the average mark was 31 %. The responses from the learners interviewed showed that they were motivated and that the use of physical manipulatives assisted them in understanding the concepts of measurement, in particular surface area and volume. The results of my study thus reveal that the use of physical manipulatives in teaching and learning mathematics has a positive role to play in learners' understanding of surface area and volume at the Grade 8 level. The fmdings of this case study support other research regarding the importance of using physical manipulatives in teaching and learning mathematics. They align with other findings that assert that manipulatives are essential mediating tools in the development of the conceptual and procedural understanding of mathematical concepts, clarifying and helping learners to visualize abstract mathematical concepts

    Prenylated Quinolinecarboxylic Acid Derivative Prevents Neuronal Cell Death Through Inhibition of MKK4

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    The development of neuroprotective agents is necessary for the treatment of neurodegenerative diseases. Here, we report PQA-11, a prenylated quinolinecarboxylic acid (PQA) derivative, as a potent neuroprotectant. PQA-11 inhibits glutamate-induced cell death and caspase-3 activation in hippocampal cultures, as well as inhibits N-Methyl-4-phenylpyridinium iodide- and amyloid β1-42-induced cell death in SH-SY5Y cells. PQA-11 also suppresses mitogen-activated protein kinase kinase 4 (MKK4) and c-jun N-terminal kinase (JNK) signaling activated by these neurotoxins. Quartz crystal microbalance analysis and in vitro kinase assay reveal that PQA-11 interacts with MKK4, and inhibits its sphingosine-induced activation. The administration of PQA-11 by intraperitoneal injection alleviates 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced degeneration of nigrostriatal dopaminergic neurons in mice. These results suggest that PQA-11 is a unique MKK4 inhibitor with potent neuroprotective effects in vitro and in vivo. PQA-11 may be a valuable lead for the development of novel neuroprotectants

    Interleukin-1β Maturation Triggers Its Relocation to the Plasma Membrane for Gasdermin-D-Dependent and -Independent Secretion.

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    IL-1β requires processing by caspase-1 to generate the active, pro-inflammatory cytokine. Acute IL-1β secretion from inflammasome-activated macrophages requires caspase-1-dependent GSDMD cleavage, which also induces pyroptosis. Mechanisms of IL-1β secretion by pyroptotic and non-pyroptotic cells, and the precise functions of caspase-1 and GSDMD therein, are unresolved. Here, we show that, while efficient early secretion of endogenous IL-1β from primary non-pyroptotic myeloid cells in vitro requires GSDMD, later IL-1β release in vitro and in vivo proceeds independently of GSDMD. IL-1β maturation is sufficient for slow, caspase-1/GSDMD-independent secretion of ectopic IL-1β from resting, non-pyroptotic macrophages, but the speed of IL-1β release is boosted by inflammasome activation, via caspase-1 and GSDMD. IL-1β cleavage induces IL-1β enrichment at PIP2-enriched plasma membrane ruffles, and this is a prerequisite for IL-1β secretion and is mediated by a polybasic motif within the cytokine. We thus reveal a mechanism in which maturation-induced IL-1β trafficking facilitates its unconventional secretion

    Getting more than they realized they needed: a qualitative study of women's experience of group prenatal care

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    <p>Abstract</p> <p>Background</p> <p>Pregnant women in Canada have traditionally received prenatal care individually from their physicians, with some women attending prenatal education classes. Group prenatal care is a departure from these practices providing a forum for women to experience medical care and child birth education simultaneously and in a group setting. Although other qualitative studies have described the experience of group prenatal care, this is the first which sought to understand the central meaning or core of the experience. The purpose of this study was to understand the central meaning of the experience of group prenatal care for women who participated in CenteringPregnancy through a maternity clinic in Calgary, Canada.</p> <p>Methods</p> <p>The study used a phenomenological approach. Twelve women participated postpartum in a one-on-one interview and/or a group validation session between June 2009 and July 2010.</p> <p>Results</p> <p>Six themes emerged: (1) "getting more in one place at one time"; (2) "feeling supported"; (3) "learning and gaining meaningful information"; (4) "not feeling alone in the experience"; (5) "connecting"; and (6) "actively participating and taking on ownership of care". These themes contributed to the core phenomenon of women "getting more than they realized they needed". The active sharing among those in the group allowed women to have both their known and subconscious needs met.</p> <p>Conclusions</p> <p>Women's experience of group prenatal care reflected strong elements of social support in that women had different types of needs met and felt supported. The findings also broadened the understanding of some aspects of social support beyond current theories. In a contemporary North American society, the results of this study indicate that women gain from group prenatal care in terms of empowerment, efficiency, social support and education in ways not routinely available through individual care. This model of care could play a key role in addressing women's needs and improving health outcomes.</p

    Methyltransferase Dnmt3a upregulates HDAC9 to deacetylate the kinase TBK1 for activation of antiviral innate immunity

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    The DNA methyltransferase Dnmt3a has high expression in terminally differentiated macrophages; however, its role in innate immunity remains unknown. Here we report that deficiency in Dnmt3a selectively impaired the production of type I interferons triggered by pattern-recognition receptors (PRRs), but not that of the proinflammatory cytokines TNF and IL-6. Dnmt3a-deficient mice exhibited enhanced susceptibility to viral challenge. Dnmt3a did not directly regulate the transcription of genes encoding type I interferons; instead, it increased the production of type I interferons through an epigenetic mechanism by maintaining high expression of the histone deacetylase HDAC9. In turn, HDAC9 directly maintained the deacetylation status of the key PRR signaling molecule TBK1 and enhanced its kinase activity. Our data add mechanistic insight into the crosstalk between epigenetic modifications and post-translational modifications in the regulation of PRR signaling and activation of antiviral innate immune responses
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