Using tasks to explore teacher knowledge in situation-specific contexts

This article was published in the journal, Journal of Mathematics Teacher Education [© Springer] and the original publication is available at www.springerlink.comResearch often reports an overt discrepancy between theoretically/out-of context expressed teacher beliefs about mathematics and pedagogy and actual practice. In order to explore teacher knowledge in situation-specific contexts we have engaged mathematics teachers with classroom scenarios (Tasks) which: are hypothetical but grounded on learning and teaching issues that previous research and experience have highlighted as seminal; are likely to occur in actual practice; have purpose and utility; and, can be used both in (pre- and in-service) teacher education and research through generating access to teachers’ views and intended practices. The Tasks have the following structure: reflecting upon the learning objectives within a mathematical problem (and solving it); examining a flawed (fictional) student solution; and, describing, in writing, feedback to the student. Here we draw on the written responses to one Task (which involved reflecting on solutions of x+x−1=0 of 53 Greek in-service mathematics teachers in order to demonstrate the range of teacher knowledge (mathematical, didactical and pedagogical) that engagement with these tasks allows us to explore

Crucial cross-talk of interleukin-1β and progesterone in human choriocarcinoma

Copyright @ 2012 Spandidos Publications Ltd. This article can be accessed from the links below.This article has been made available through the Brunel Open Access Publishing Fund.Choriocarcinoma is a highly malignant epithelial tumour that is most often associated with hydatidiform mole and presents the most common emergency medical problem in the management of trophoblast disease. We hypothesise that the hormones/cytokines present within the tumour microenvironment play key roles in the development of choriocarcinoma. In this study we assessed the effects of interleukin-1β (IL-1β) on cell death in the presence or absence of the sex hormone progesterone using two choriocarcinoma cell lines (BeWo and JEG-3) as in vitro experimental models. Although IL-1β induced cell death in both cell lines, the effect was more pronounced in JEG-3 cells, where cell death reached 40% compared to 15% in BeWo cells. Cell death of JEG-3 cells in response to IL-1β was significantly decreased by co-treatment with 100 nM and 1000 nM progesterone and completely abolished at a progesterone concentration of 1000 nM. Progesterone was also able to induce phosphorylation of ERK1/2 in these cells. Pretreatment of JEG-3 cells with a specific MAPK inhibitor (UO126) inhibited progesterone's inhibitory effect on cell death. Collectively, these data provide evidence of cross-talk between progesterone and IL-1β in this aggressive and poorly understood tumour that involves activation of a MAPK pathway and involvement of numerous progesterone receptors.This research was funded by a National Institutes of Health Grant ESO12961. This article is made available through the Brunel Open Access Publishing Fund

Using tasks to explore teacher knowledge in situation-specific contexts

Research often reports an overt discrepancy between theoretically/out-of context expressed teacher beliefs about mathematics and pedagogy and actual practice. In order to explore teacher knowledge in situation-specific contexts we have engaged mathematics teachers with classroom scenarios (Tasks) which: are hypothetical but grounded on learning and teaching issues that previous research and experience have highlighted as seminal; are likely to occur in actual practice; have purpose and utility; and, can be used both in (pre- and in-service) teacher education and research through generating access to teachers’ views and intended practices. The Tasks have the following structure: reflecting upon the learning objectives within a mathematical problem (and solving it); examining a flawed (fictional) student solution; and, describing, in writing, feedback to the student. Here we draw on the written responses to one Task (which involved reflecting on solutions of x+x−1=0 of 53 Greek in-service mathematics teachers in order to demonstrate the range of teacher knowledge (mathematical, didactical and pedagogical) that engagement with these tasks allows us to explore

Bulletin

https://openspace.dmacc.edu/bulletin/1001/thumbnail.jp

Recent Common Ancestry of Ebola Zaire Virus Found in a Bat Reservoir

No abstract available

بررسی علت و انواع شکستگی فک در بیمارستان‌های آموزشی یزد، سال‌های 1373 و 1374

زمینه و هدف: در مقـایسه با سایر مـردم دنیا، ایرانیـان بیشتـر قـربانی حوادث ترافیکـی می‌شـوند به طوری که بیشتـرین مـرگ و میـر کشور ما بعد از حوادث قلبی ـ عـروقی در اثر حـوادث ترافیکی اتفاق می‌افتد. تعداد زیادی از مصدومین تـروما دچار ضربه سر و گـردن می‌شوند. مواد و روش‌ها: ما در این مطالعه خصوصیات دموگـرافیک، بالینی، نوع و علت 159 مورد بیمار با شکستگی فک بستـری شده در بیمارستان‌های آموزشی یزد طی سال‌های 73-74 مـورد بررسی قرار دادیم. یافته‌ها: در این مطالعـه توصیفـی که به روش مقطعـی انجـام شـده است 138 بیمـار مـرد (87%) و 21 بیمـار زن (13%) مـورد بـررسی قـرار گرفتند. بیمـاران 3 تا 83 سالـه بـودند. میـزان 8/52% بیمـاران بیـن 20 تا 39 سـال داشتنـد. نـود و پنـج شکستگـی مندیبـولار (75/59%) و 52 بیمـار ماگـزیلاری (7/32%) و 12 مـورد (55/7%) شکستگـی هـر دو فـک داشتنـد. در 123 مـورد (4/77%) علـت، تصادفـات راننـدگی، 28 مـورد سقـوط (6/17%) و 8 مـورد نزاع (5%) بـوده است. 39/17% شکستگی‌های مندیبـولار پـاراسمفیـزیال 22/15%، در ناحیـه زاویـه 36/25، در ناحیـة تنـه 97/7%، در ناحیـه رامــوس و 62/3% در ناحیـه کـورونوئید بـوده اسـت. میـزان 5/37% شکستگـی‌های ماگـزیلا از نوع لیفـورت II، 19/17% لیفـورت I، 5/12% لیفـورت III و 56/1% آلوئولار بـوده است. نتیجه‌گیـری: مقایسه یافته‌های این مطالعه با مطالعـات مشابه نشان دهنده این واقعیت است که بروز این ضایعـات در کشورهای مختلف با هم تفاوت‌های زیادی دارند