A metacognitive intervention for teaching fractions to students with or at-risk for learning disabilities in mathematics

Assessment data from the United States and international reports of student achievement indicate that upper elementary students are failing to meet basic levels of proficiency in fractions and writing, and that this is particularly prevalent with students with or at-risk for learning disabilities in mathematics. Proficiency with fractions has been identified as foundational for learning higher-level mathematics but remains one of the most difficult skills for students to learn. In addition, students' difficulty with fractions is exacerbated because of increased chances of comorbidity with language learning problems, particularly difficulties constructing arguments and communicating using writing. We describe FACT+(RC2)-C-2, a language-based, metacognitive instructional intervention that was designed using the Self-Regulated Strategy Development model (SRSD) for teaching foundational concepts of fractions. The results from two studies in which the intervention was administered to upper elementary students who exhibit mathematics difficulties indicated selected increases in students' computational accuracy, quality of mathematical reasoning, number of rhetorical elements, and total words. With evidence of improved performance in these areas, FACT+(RC2)-C-2 holds promise for helping these students become proficient self-regulated learners.12 month embargo; published online: 18 March 2019This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Transgressions and Regressions in the Barataria Bight Region of Coastal Louisiana. (Volumes I and II).

At least three delta progradations have contributed to the Barataria geologic framework since 5000 ybp. The Bayou des Families lobe was first (4600 to 3600 ybp) followed by Bayou Blue (2600 and 1900 ybp) and then the Mississippi lobe (1000 ybp to the present). A flooding surface separates the (lower) Bayou des Families from the Bayou Blue progradation (above). The shoreface of the Bayou des Families transgression lies seaward of the present Barataria shoreline. This transgression lasted approximately one thousand years. A flooding surface also separates the Bayou Blue progradation from the Mississippi Delta lobe. This (Bayou Blue) transgression lasted 900 years, was halted near the present shoreline, and can be traced from the Caminada headland to the meander bend of the Mississippi River at Nairns, Louisiana. Rates of relative sea level rise recorded in the subsurface of the Mississippi River delta plain decrease from 1.0 cm/yr in the top meter to less than 0.20 cm/yr at three meters. In recently abandoned delta lobes the high initial rate of subsidence contributes to rapid increases in bay area and tidal prism. This increase has caused the Barataria tidal inlets to evolve from wave-dominated to tide-dominated inlets within the past 150 years. In the late stages of delta lobe abandonment sediment supply to barriers islands becomes critically low. The inlets widen causing tidal currents to decrease. This causes the once tide-dominated inlets to become wave influenced. Dynamic coastal processes in the bays, inlets, and on the shoreface all contribute to the low preservation potential for Barataria shoreline sediments following the present transgression. Preservation, if any, will be limited to inlet channels scoured beneath the shoreface depth. The processes occurring along the Barataria shoreline are probably similar to those that occurred during past Holocene delta plain transgressions. By understanding the links between landloss and tidal inlet evolution during delta lobe abandonment the success of future Barataria barrier shoreline preservation programs may be improved. Bay area reduction by wetland restoration may reduce tidal currents through an inlet/barrier system. This activity combined with sand nourishment of the barrier shoreline should help save the Barataria Bay ecosystem

Geographic and socioeconomic variations in adolescent toothbrushing: a multilevel cross-sectional study of 15 year olds in Scotland

Background: This study examined urban–rural and socioeconomic differences in adolescent toothbrushing. Methods: The data were modelled using logistic multilevel modelling and the Markov Chain Monte Carlo method of estimation. Twice-a-day toothbrushing was regressed upon age, family affluence, family structure, school type, area-level deprivation and rurality, for boys and girls separately. Results: Boys’ toothbrushing was associated with area-level deprivation but not rurality. Variance at the school level remained significant in the final model for boys' toothbrushing. The association between toothbrushing and area-level deprivation was particularly strong for girls, after adjustment for individuals’ family affluence and type of school attended. Rurality too was independently significant with lower odds of brushing teeth in accessible rural areas. Conclusion: The findings are at odds with the results of a previous study which showed lower caries prevalence among children living in rural Scotland. A further study concluded that adolescents have a better diet in rural Scotland. In total, these studies highlight the need for an examination into the relative importance of diet and oral health on caries, as increases are observed in population obesity and consumption of sugars

Western European N2O emissions: A top-down approach based on atmospheric observations

We present a three-year record of continuous gas chromatographic nitrous oxide (N2O) observations performed at the urban station Heidelberg (Germany) together with weekly flask data from a remote continental site, Schauinsland (Black Forest, Germany), and two-weekly integrated data from the maritime background station Izaña (Canary Islands). These data are supplemented by continuous atmospheric radon-222 observations. Mean rates of increase of N2O of 0.70–0.78 ppb/yr were observed over the continent and in maritime background air (Izana). The well-mixed continental mixing ratio was found to be higher by only 1.1 ppb (Schauinsland) and 2.4 ppb (Heidelberg) than for maritime background air. Specially tailored data selection of the Heidelberg record allowed the changing influence of a regional N2O point source (adipic acid production, BASF AG) to be clearly identified. The radon (222Rn) tracer method was applied to nighttime N2O observations at Heidelberg to estimate mean regional emissions, which changed from (161±32) µg N2O-N/m2/h in 1996/1997 to (77±10) µg N2O-N /m2/h1 in 1998 as a consequence of 90% emission reduction from BASF. An estimate of the continental N2O flux from southwestern Europe based on further selected Heidelberg data (only well-mixed, late afternoon situations) and observations from the Schauinsland station yielded mean N2O fluxes of (43±5) µg N2O-N m–2h–1 and (42±4) µg N2O-N /m2/h1. These results compare well with statistical emissions inventories, when taking into account possible systematic errors of the radon tracer method of 30-35%

Verification of German methane emission inventories and their recent changes based on atmospheric observations

Continuous methane concentration records and stable isotope observations measured in the suburbs of Heidelberg, Germany, are presented. While delta13C-CH4 shows a significant trend of -0.14 permil per year, towards more depleted values, no trend is observed in the concentration data. Comparison of the Heidelberg records with clean air observations in the North Atlantic at Izana station (Tenerife) allows the determination of the continental methane excess at Heidelberg, decreasing by 20% from 190 ppb in 1992 to 150 ppb in 1997. The isotope ratio which is associated with this continental methane pile-up in the Heidelberg catchment area shows a significant trend to more depleted values from delta13C (source) = -47.4 ± 1.2 permil in 1992 to 52.9 ± 0.4 permil in 1995/96, pointing to a significant change in the methane source mix. Total methane emissions in the Heidelberg catchment area are estimated using the 222Radon (222Rn) tracer method: from the correlations of half hourly 222Rn and CH4 mixing ratios from 1995 to 1997, and the mean 222Rn exhalation rate from typical soils in the Rhine valley, a mean methane flux of 0.24 ± 0.5 g CH4 km-2 s-1 is derived. For the Heidelberg catchment area with an estimated radius of approximately 150 km, Core Inventories Air 1990 (CORINAIR90) emission estimates yield a flux of 0.47 g CH4 km-2 s-1, which is about 40% higher than the 222Rn derived number if extrapolated to 1990. The discrepancy can be explained by over-estimated emissions from waste management in the CORINAIR90 statistical assessment. The observed decrease in total emissions can be accounted for by decreasing contributions from fossil sources (mainly coal mining) and from cattle breeding. This finding is also supported by the observed decrease in mean source isotopic signatures

Corporate Bankruptcy Panel--The Fraudulent Conveyance Origins of Chapter 11: An Essay on the Unwritten Law of Corporate Reorganizations

The second panel was the Corporate Panel, led by Professor Douglas Baird from the University of Chicago Law School. We were fortunate enough to have the impressive Sarah R. Borders act as the moderator of this panel. The discussion, however, did not require much moderating; the panelists were familiar with one another and the discussion was entertaining. The panel was divided into two schools of thought: those who felt like the Code solely governed the practice of corporate bankruptcy, and those who felt like there was a set of unwritten rules created over the last 150 years that pulled the strings

SUSY field theories, integrable systems and their stringy/brane origin -- II

Five and six dimensional SUSY gauge theories, with one or two compactified directions, are discussed. The 5d theories with the matter hypermultiplets in the fundamental representation are associated with the twisted $XXZ$ spin chain, while the group product case with the bi-fundamental matter corresponds to the higher rank spin chains. The Riemann surfaces for $6d$ theories with fundamental matter and two compact directions are proposed to correspond to the $XYZ$ spin chain based on the Sklyanin algebra. We also discuss the obtained results within the brane and geometrical engeneering frameworks and explain the relation to the toric diagrams.Comment: LaTeX, 21 pages, no figure