28 research outputs found

    Assessing Students\u27 Understanding of Variability and Graph Interpretation Through an Authentic Science Investigation

    Get PDF
    This thesis research combined efforts of two existing projects at the University of Maine in collaboration with the Schoodic Institute, the Acadia Learning Snowpack Project and the Maine Data Literacy Project. The Snowpack Project provided a context to explore student learning of variability and graphing skills by gathering data on snowfall and accumulation throughout the winter and using the data to ask and answer a scientific question. The Maine Data Literacy Project provided a framework and instruments for assessing students’ understanding of variability and graph interpretation skills. The first goal of this research was to measure student learning about variability during the Snowpack Project. The study used a pretest posttest design and the multiple-choice ASK-Var assessment developed by the Maine Data Literacy Project. Data were first collected in January and May of 2015. When no differences were found, additional data from Snowpack Project students the following September and a separate group of seventh graders were analyzed to give a broader context. The second goal of this research was to compare the multiple-choice ASK-Var assessment to an open-response assessment. This analysis used a correlation to measure how predictive success on the ASK-Var assessment was to success on the open-response assessment. The third goal of thesis research was to describe what the results of both assessments revealed about student thinking around variability. This uses qualitative analyses to identify patterns in student thinking about histograms, box plots, and graph choice. No quantitative differences were found between students before and after participating in the snowpack project, however there was some evidence suggesting that the high school Snowpack Project students did perform better than the seventh grade students. Data on the ASK-Var assessment and the open-response assessment correlated, but randomness under the surface suggested that there were skills being tested in the open-response assessment that were not being measured by the ASK-Var assessment. Finally, the qualitative analysis suggested that while students were generally able to read frequency plots, they sometimes inappropriately applied important context to their interpretations. The graph construction task revealed a split among students’ ability to interpret their own graphs. Those who chose to display the data in frequency plots had a higher rate of success in accurately interpreting the results. This study offers insights into applications of the ASK-Var assessment and student thinking about graphing and variability

    Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

    Get PDF
    BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

    Forest fire plumes over the North Atlantic: p-TOMCAT model simulations with aircraft and satellite measurements from the ITOP/ICARTT campaign

    Get PDF
    Intercontinental Transport of Ozone and Precursors (ITOP) (part of International Consortium for Atmospheric Research on Transport and Transformation (ICARTT)) was an intense research effort to measure long-range transport of pollution across the North Atlantic and its impact on O3 production. During the aircraft campaign plumes were encountered containing large concentrations of CO plus other tracers and aerosols from forest fires in Alaska and Canada. A chemical transport model, p-TOMCAT, and new biomass burning emissions inventories are used to study the emissions long-range transport and their impact on the troposphere O3 budget. The fire plume structure is modeled well over long distances until it encounters convection over Europe. The CO values within the simulated plumes closely match aircraft measurements near North America and over the Atlantic and have good agreement with MOPITT CO data. O3 and NOx values were initially too great in the model plumes. However, by including additional vertical mixing of O3 above the fires, and using a lower NO2/CO emission ratio (0.008) for boreal fires, O3 concentrations are reduced closer to aircraft measurements, with NO2 closer to SCIAMACHY data. Too little PAN is produced within the simulated plumes, and our VOC scheme's simplicity may be another reason for O3 and NOx model-data discrepancies. In the p-TOMCAT simulations the fire emissions lead to increased tropospheric O3 over North America, the north Atlantic and western Europe from photochemical production and transport. The increased O3 over the Northern Hemisphere in the simulations reaches a peak in July 2004 in the range 2.0 to 6.2 Tg over a baseline of about 150 Tg

    Progenitor cell release plus exercise to improve functional performance in peripheral artery disease: The PROPEL Study

    No full text
    Functional impairment, functional decline, and mobility loss are major public health problems in people with lower extremity peripheral artery disease (PAD). Few medical therapies significantly improve walking performance in PAD. We describe methods for the PROgenitor cell release Plus Exercise to improve functionaL performance in PAD (PROPEL) Study, a randomized controlled clinical trial designed to determine whether granulocyte-macrophage colony stimulating factor (GM-CSF) combined with supervised treadmill walking exercise improves six-minute walk distance more than GM-CSF alone, more than supervised treadmill exercise alone, and more than placebo plus attention control in participants with PAD, respectively. PROPEL Study participants are randomized to one of four arms in a 2 by 2 factorial design. The four study arms are GM-CSF plus supervised treadmill exercise, GM-CSF plus attention control, placebo plus supervised exercise therapy, or placebo plus attention control. The primary outcome is change in six-minute walk distance at 12-week follow-up. Secondary outcomes include change in brachial artery flow-mediated dilation (FMD), change in maximal treadmill walking time, and change in circulating CD34+ cells at 12-week follow-up. Outcomes are also measured at six-week and six-month follow-up. Results of the PROPEL Study will have important implications for understanding mechanisms of improving walking performance and preventing mobility loss in the large and growing number of men and women with PAD

    Profluorogenic Reductase Substrate for Rapid, Selective, and Sensitive Visualization and Detection of Human Cancer Cells that Overexpress NQO1

    No full text
    Achieving the vision of identifying and quantifying cancer-related events and targets for future personalized oncology is predicated on the existence of synthetically accessible and economically viable probe molecules fully able to report the presence of these events and targets in a rapid, and highly selective and sensitive fashion. Delineated here are the design and evaluation of a newly synthesized turn-on probe whose intense fluorescent reporter signature is revealed only through probe activation by a specific intracellular enzyme present in tumor cells of multiple origins. Quenching of molecular probe fluorescence is achieved through unique photo-induced electron transfer (PeT) between the naphthalimide dye reporter and a covalently attached, quinone-based enzyme substrate. Fluorescence of the reporter dye is turned on by rapid removal of the quinone quencher, an event that immediately occurs only after highly selective, two-electron reduction of the sterically and conformationally restricted quinone substrate by the cancer-associated human NAD(P)H:quinone oxidoreductase isozyme 1 (hNQO1). Successes of the approach include rapid differentiation of NQO1-expressing and non-expressing cancer cell lines via the unaided eye, flow cytometry, fluorescence imaging, and two-photon microscopy. The potential for use of the turn-on probe in longer-term cellular studies is indicated by its lack of influence on cell viability and its in vitro stability

    Private legal transplant : multinational enterprises as proxies of legal homogenisation

    No full text
    Recent decades have been characterised by a surge in foreign direct investments and the expansion of global production networks as a new model of production. However, while hundreds of studies have been produced, little attention has been paid to the legal transformations that are taking place whenever transnational enterprises (TNEs) physically or contractually occupy space within national legal orders. In this article, I expand the scope of the traditional theory of legal transplant to look at foreign direct investments and codes of conduct, and conclude that they create special legal zones—separate sub-regimes where TNEs exercise their de facto jurisdiction. Thus, looking at the micro-mechanisms of legal reproduction we discover the limitedness of traditional theories of legal transplant and that, while critics of legal transplant stand in front of their houses to fight against the hegemony of legal and cultural homogenisation, their enemy is entering by the back door
    corecore