Making Meaning Of Multiplication: Integrating Virtual Manipulatives And Think-Alouds With Repeated Addition, Arrays, And Decomposing Numbers To Build Conceptual Understandings

The purpose of this action research was to evaluate the implementation of technology integration with multiplication concepts (i.e., repeated, arrays, and decomposing numbers) for struggling third grade mathematics students. This study incorporated the use of virtual manipulatives and student think-aloud recordings to measure students’ conceptual understanding of basic multiplication. This study focused on two overarching research questions: (1) The first question explored how technology integration with multiplication concepts (i.e., repeated addition, arrays, and decomposing numbers) impacted student understanding; and (2) the second question explored how students select and explain strategies for solving multiplication problems. Data collection consisted of teacher-made pre- and posttests with virtual manipulatives and student thinkaloud recordings. Data analysis incorporated an evaluative mixed-methods approach using objective assessment data with non-parametric tests and constant comparative method. After transcribing, reviewing, and coding data, overlapping themes emerged, including students’ conceptual understandings, students’ conceptual misunderstandings, and students’ correct methodology with careless errors. (Careless errors in this study refers to simple errors in counting or adding. In several cases, the students used virtual manipulatives to build the problems correctly but made errors when counting or adding the manipulatives). Findings revealed that virtual manipulatives significantly improved participants’ conceptual understandings of all three given multiplication strategies. The impact of vi virtual manipulatives is reflected in the increased percentages of students who demonstrated conceptual understanding of the three strategies from the end of week one to end of the innovation. Conceptual understanding for each of the strategies (i.e., repeated addition, arrays, and decomposing numbers) increased by 40 percent over the course of this innovation. In addition, the impact of virtual manipulatives and think-aloud recordings is reflected in the increase of correct scores from the pretest to posttest. Four Wilcoxon Signed-ranks tests were conducted for (1) overall pretest-posttest scores and the three specific strategies (2) repeated addition pretest-posttest scores, (3) arrays pretest-posttest scores, and (4) decomposing numbers pretest-posttest scores. All four tests were statistically significant with posttest scores higher than pretest scores. The student think-aloud self-recordings provided valuable insight into students’ developing conceptual understandings, and consequently helped guide and direct remediation throughout this innovation. By listening to their own recordings, students were able to evaluate their work, identify mistakes, and correct careless errors before turning in their recordings. Consequently, the think-aloud recordings promoted student self-reflection and were essential in providing specific, individualized instruction for all participant

GENERALIZED LINEAR MIXED MODEL ESTIMATION USING PROC GLIMMIX: RESULTS FROM SIMULATIONS WHEN THE DATA AND MODEL MATCH, AND WHEN THE MODEL IS MISSPECIFIED

A simulation study was conducted to determine how well SAS® PROC GLIMMIX (SAS Institute, Cary, NC), statistical software to fit generalized linear mixed models (GLMMs), performed for a simple GLMM, using its default settings, as a naïve user would do. Data were generated from a wide variety of distributions with the same sets of linear predictors, and under several conditions. Then, the data sets were analyzed by using the correct model (the generating model and estimating model were the same) and, subsequently, by misspecifying the estimating model, all using default settings. The data generation model was a randomized complete block design where the model parameters and sample sizes were adjusted to yield 80% power for the F-test on treatment means given a 30 block experiment with block-by-treatment interaction and with additional treatment replications within each block. Convergence rates were low for the exponential and Poisson distributions, even when the generating and estimating models matched. The normal and lognormal distributions converged 100% of the time; convergence rates for other distributions varied. As expected, reducing the number of blocks from 30 to five and increasing replications within blocks to keep total N the same reduced power to 40% or less. Except for the exponential distribution, estimates of treatment means and variance parameters were accurate with only slight biases. Misspecifying the estimating model by omitting the block-by-treatment random effect made F-tests too liberal. Since omitting that term from the model, effectively ignoring a process involved in giving rise to the data, produces symptoms of over-dispersion, several potential remedies were investigated. For all distributions, the historically recommended variance stabilizing transformation was applied, and then the transformed data were fit using a linear mixed model. For one-parameter members of the exponential family an over-dispersion parameter was included in the estimating model. The negative binomial distribution was also examined as the estimating model distribution. None of these remedial steps corrected the over-dispersion problem created by misspecifying the linear predictor, although using a variance stabilizing transformation did improve convergence rates on most distributions investigated

Vesicular Glutamate Transporter 3 in age-dependent optic neuropathy

To determine retinal vesicular glutamate transporter 3 (VGLUT3) expression alterations in a mouse model of progressive optic neuropathy (glaucoma). Tissue specimens were obtained from age-matched DBA/2J and control C57BL/6J mice for western blot analysis. Enucleated globes from DBA/2J, C57BL/6J, and BALB/cJ mice were fixed in formalin, paraffin-embedded, and sectioned for VGLUT3 protein localization. western blot analysis of the control retinas revealed the expression of a ~55 kDa immunoreactive VGLUT3 protein that is to be expected in tissues such as retina, brain, liver, heart, and kidney tissue, but not in intestinal or lung tissue. Furthermore, a strong ~130 kDa immunoreactive VGLUT3 isoform that is restricted to the central nervous system (the brain and retinas) was also identified in the controls, but was not detected in the DBA/2J retinas. Immunofluorescence microscopy showed a lack of VGLUT3 expression in the synapses between amacrine and retinal ganglion cells in DBA/2J retinas, in contrast to its strong expression in the C57BL/6J and BALB/cJ controls. Our results implicate the dysregulated expression of a central nervous system-specific VGLUT3 isoform as a predisposing factor in the development of optic neuropathy in DBA/2J mice, a spontaneous mouse model of glaucoma. In striking parallel to the visual system defects of glaucomatous DBA/2J mice, the inner ear of VGLUT3 knockout mice displays a progressive loss of inner hair cell to spiral-ganglion neuron synapses. A significant reduction in the number of spiral-ganglion neurons leads to age-associated deafness. Thus, we propose that the absence of this biochemically uncharacterized 130 kDa VGLUT3 isoform in the DBA/2J retina is a predisposing factor in synaptic instability, and a contributing factor in the age-dependent and progressive loss of ganglion cells projecting to the brain

Testing Prospects for Reliable Diatom Nanotechnology in Microgravity

The worldwide effort to grow nanotechnology, rather than use lithography, focuses on diatoms, single cell eukaryotic algae with ornate silica shells, which can be replaced by oxides and ceramics, or reduced to elemental silicon, to create complex nanostructures with compositions of industrial and electronics importance. Diatoms produce an enormous variety of structures, some of which are microtubule dependent and perhaps sensitive to microgravity. The NASA Single Loop for Cell Culture (SLCC) for culturing and observing microorganisms permits inexpensive, low labor in-space experiments. We propose to send up to the International Space Station diatom cultures of the three diatom species whose genomes are being sequenced, plus the giant diatoms of Antarctica (up to 2 mm diameter for a single cell) and the unique colonial diatom, Bacillaria paradoxa. Bacillaria cells move against each other in partial synchrony, like a sliding deck of cards, by a microfluidics mechanism. Will normal diatoms have aberrant pattern and shape or motility compared to ground controls? The generation time is typically one day, so that many generations may be examined from one flight. Rapid, directed evolution may be possible running the SLCC as a compustat. The shell shapes and patterns are preserved in hard silica, so that the progress of normal and aberrant morphogenesis may be followed by drying samples on a moving filter paper "diatom tape recorder". With a biodiversity of 100,000 distinct species, diatom nanotechnology may offer a compact and portable nanotechnology toolkit for exploration anywhere

Dual-locus DNA metabarcoding reveals southern hairy-nosed wombats (Lasiorhinus latifrons Owen) have a summer diet dominated by toxic invasive plants

Habitat degradation and summer droughts severely restrict feeding options for the endangered southern hairy-nosed wombat (SHNW; Lasiorhinus latifrons). We reconstructed SHNW summer diets by DNA metabarcoding from feces. We initially validated rbcL and ndhJ diet reconstructions using autopsied and captive animals. Subsequent diet reconstructions of wild wombats broadly reflected vegetative ground cover, implying local rather than long-range foraging. Diets were all dominated by alien invasives. Chemical analysis of alien food revealed Carrichtera annua contains high levels of glucosinolates. Clinical examination (7 animals) and autopsy (12 animals) revealed that the most degraded site also contained most individuals showing signs of glucosinolate poisoning. We infer that dietary poisoning through the ingestion of alien invasives may have contributed to the recent population crashes in the region. In floristically diverse sites, individuals appear to be able to manage glucosinolate intake by avoidance or episodic feeding but this strategy is less tractable in the most degraded sites. We conclude that recovery of the most affected populations may require effective Carrichtera management and interim supplementary feeding. More generally, we argue that protection against population decline by poisoning in territorial herbivores requires knowledge of their diet and of those food plants containing toxic principles

Improving biocontrol using antagonist mixtures with heat and/or sodium bicarbonate to control postharvest decay of apple fruit

Abstract 'Golden Delicious' apples were wound-inoculated with either Colletotrichum acutatum or Penicillium expansum and then treated with various combinations of heat (38 • C) for 4 days, 2% sodium bicarbonate, and two biocontrol agents alone or combined. The fruit were stored for 4 months at 1 • C and then at 20 • C for 2 weeks. Either heat or the antagonists reduced decay caused by C. acutatum, but a combination of the two was required to completely eliminate decay caused by this pathogen in most cases. Sodium bicarbonate alone or in combination with the antagonists had little effect on C. acutatum. The antagonists alone reduced decay caused by P. expansum but tended to be more effective when combined. Sodium bicarbonate increased the effectiveness of decay control by each antagonist alone or in combination. All of the treatments that included heat virtually eliminated decay caused by this pathogen. The proper combination of alternative control measures can provide an effective strategy to reduce postharvest decay of apple fruit. Published by Elsevier B.V

LMDA Review, volume 10, issue 1

Contents include: Photo of Conference Participants Annual Conference 1999, Send in your Ballot, A Note to Ourselves, Increase in Dues and New Annual Membership Expiration Date, LMDA Archive, LMDA Administrator; LMDA Interns, Mid-Year Meeting, Early Career Dramaturg Program, Elliot Hayes Award 2000, Report on Canadian Caucus, Script Exchange, Report on the Dramaturgy Focus Group ATHE 1999, Elliot Hayes Award Winners Lue Douthit and Michel Volansky, Acceptance Speech Lue Morgan Douthit, Elliot Hayes Award Presentation to Michele Volansky for Space, On the Elliot Hayes Award Michele Volansky, Day One of the Conference, Day Two of the Conference, Day Three of the Conference, Day Four of the Conference, The Advocacy Caucus Presentation at the Conference, Final Thoughts, Conference 1999 Many Thanks, Arthur Ballet and the Office for Advanced Drama Research, Spotlight on Early Career Dramaturg Vanessa Porteous, A Working History of LMDA The Early Years, From Academia to Arena A Dramaturg\u27s Education in the Real World, Tony Creamer and Death of a Salesman, Two Moments, Jobs and Projects, Scriptseeker.com, LMDA Online Listserv Instructions, Note from James Magruder, Literary Managers and Dramaturgs of the Americas Bibliography 1999, Noted with Pleasure, and Internship Questionnaire.https://soundideas.pugetsound.edu/lmdareview/1020/thumbnail.jp

Advancing the human right to housing in post-Katrina New Orleans: discursive opportunity structures in housing and community development

In post-Katrina New Orleans, housing and community development (HCD) advocates clashed over the future of public housing. This case study examines the evolution of and limits to a human right to housing frame introduced by one nongovernmental organization (NGO). Ferree’s concept of the discursive opportunity structure and Bourdieu’s social field ground this NGO’s failure to advance a radical economic human rights frame, given its choice of a political inside strategy that opened up for HCD NGOs after Hurricane Katrina. Strategic and ideological differences within the field limited the efficacy of this rights-based frame, which was seen as politically radical and risky compared with more resonant frames for seeking affordable housing resources and development opportunities. These divides flowed from the position of the movement-born HCD field within a neoliberal political economy, especially its current institutionalization in the finance and real estate sector, and its dependence on the state for funding and political legitimacy