91 research outputs found

    The relationship between the flipped classroom and critical thinking, academic performance, student perceptions, and student evaluations in an introductory psychology course

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    For more than two centuries, traditional college instruction in America has relied upon the use of the lecture as the model for the college classroom learning environment (Christensen & Eyring, 2011; Costin, 1972; Woodard, 2011). However, criticism of the lecture has led to the development of alternative instruction models (Dillenbourg, 1999a; Prince, 2004). The flipped classroom is one of these models. The flipped classroom flips the traditional model by moving content typically delivered through a lecture to an online environment and using class time for learning activities that are active and collaborative (Abeysekera & Dawson, 2015b). Despite many advocates for using the flipped classroom model, there has been little research on how effective the model is at generating desired student outcomes. Understanding the viability of the flipped classroom for promoting learning is necessary if college educators are going to utilize the model. This study considers the flipped classroom’s effectiveness in three areas: academic performance, critical thinking, and evaluation and perception of the learning environment. Additional consideration was given to the relationship between student perception and academic performance. This mixed methods study used a quasi-experimental, within subjects design. The population was comprised of students from two sections of a General Psychology course at a private, liberal arts university during one full fall semester. Treatments were counterbalanced so that each group of participants experienced the models in a different order. Individual qualitative interviews were conducted with 11 students who were recruited from the original sample

    Ice Nucleation in Internally Mixed Ammonium Sulfate/Dicarboxylic Acid Particles

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    Recent studies have shown that tropospheric sulfate aerosols commonly contain 50% or more by mass organic species. The influence of these organics on the chemical and physical properties of sulfate aerosols is not fully established. Using an aerosol flow tube technique, we have determined ice nucleation temperatures for particles composed of ammonium sulfate and mixtures of ammonium sulfate with a series of dicarboxylic acids. A calibration curve was developed to allow us to convert the freezing temperatures to a saturation ratio required for ice nucleation. At levels detectable by our experimental technique we find that the freezing temperatures and critical ice saturation ratios of each system were identical, for a given water activity of the solution, even though the solutions contained varying fractions of inorganic and organic components. Further experiments showed that the freezing behavior of pure dicarboxylic acid particles was identical to that of the other systems studied if the water activity was identical. Although the apparent freezing temperatures reported here are substantially warmer than those predicted by the water activity based nucleation theory of T. Koop et al., we find that solution water activity defined the freezing conditions for the systems studied here

    Deliquescence Behavior of Organic/Ammonium Sulfate Aerosol

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    Recent studies have shown that tropospheric aerosols composed of internal mixtures of organics with sulfates are quite common with the organic composing up to 50% of the particle mass. The influences of the organics on the chemical and physical properties of the aerosol are not known. In this paper, we report the solubility of a series of dicarboxylic acids in saturated ammonium sulfate solution as a function of temperature. We also report the deliquescence relative humidity (DRH) of the pure dicarboxylic acids and of mixtures of dicarboxylic acids with ammonium sulfate. For the systems studied, we find that the presence of water-soluble dicarboxylic acids caused deliquescence to occur at a lower relative humidity (RH) than pure ammonium sulfate. In contrast, the less soluble dicarboxylic acids had no measurable effect on the deliquescence relative humidity of ammonium sulfate

    Hygroscopic Growth of Ammonium Sulfate/Dicarboxylic Acids

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    Recent studies have shown that tropospheric sulfate aerosols commonly contain 50% by mass organic species. The influence of these organics on the chemical and physical properties of sulfate aerosols is not fully established. We have measured the water activity of pure dicarboxylic acids and eutonic mixtures of ammonium sulfate/dicarboxylic acids at 25°C and have calculated van\u27t Hoff factors for each individual system. We have also used the vapor pressure data to determine the hygroscopic growth curves for pure dicarboxylic acids and eutonic mixtures and provide power law fits to the data. For the systems studied we find that the presence of soluble dicarboxylic acids at the eutonic proportion depresses hygroscopic growth when compared to pure ammonium sulfate. In addition, we find that the presence of low-solubility dicarboxylic acids at the eutonic proportion has no effect on the hygroscopic growth when compared to pure ammonium sulfate. To model the hygroscopic growth curves of the eutonic solutions, we employed the Zdanovskii, Stokes, and Robinson method. It was found that this approximation was accurate to within 17% for all the systems studied

    Pediatric emergency department visits and ambient Air pollution in the

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    Estimating the health effects of ambient air pollutant mixtures is necessary to understand the risk of real-life air pollution exposures. Methods: Pediatric Emergency Department (ED) visit records for asthma or wheeze (n = 148,256), bronchitis (n = 84,597), pneumonia (n = 90,063), otitis media (n = 422,268) and upper respiratory tract infection (URI) (n = 744,942) were obtained from Georgia hospitals during 2002-2008. Spatially-contiguous daily concentrations of 11 ambient air pollutants were estimated from CMAQ model simulations that were fused with ground-based measurements. Using a case-crossover study design, odds ratios for 3-day moving average air pollutant concentrations were estimated using conditional logistic regression, matching on ZIP code, day-of-week, month, and year. Results: In multipollutant models, the association of highest magnitude observed for the asthma/wheeze outcome was with "oxidant gases" (O-3, NO2, and SO2)the joint effect estimate for an IQR increase of this mixture was OR: 1.068 (95% CI: 1.040, 1.097). The group of "secondary pollutants" (O-3 and the PM2.5 components SO42 -, NO3-, and NH4+) was strongly associated with bronchitis (OR: 1.090, 95% CI: 1.050, 1.132), pneumonia (OR: 1.085, 95% CI: 1.047, 1.125), and otitis media (OR: 1.059, 95% CI: 1.042, 1.077). ED visits for URI were strongly associated with "oxidant gases," "secondary pollutants," and the " criteria pollutants" (O-3, NO2, CO, SO2, and PM2.5). Conclusions: Short-term exposures to air pollution mixtures were associated with ED visits for several different pediatric respiratory diseases

    Phase Changes in Internally Mixed Maleic Acid/Ammonium Sulfate Aerosols

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    A temperature controlled flow tube system equipped with Fourier transform infrared (FTIR) detection of particle phase and relative humidity was used to measure the deliquescence and efflorescence of ammonium sulfate, maleic acid, and internally mixed maleic acid/ammonium sulfate particles. Our results indicate that maleic acid aerosols begin to take up water starting at a low relative humidity, ∼20%, and continue the constant uptake of water until the final deliquescence relative humidity (DRH), 89%, is reached. Internally mixed particles containing maleic acid and ammonium sulfate were found to deliquesce at a lower relative humidity (RH) than either of the pure species. Efflorescence studies indicated that while pure maleic acid particles crystallize at ∼18% RH, pure ammonium sulfate and all mixed aerosols effloresce at or just below 30% RH. Taken together, our results suggest that the presence of water-soluble organics internally mixed with ammonium sulfate aerosol could increase the range of conditions under which the aerosol is a solution

    The Vehicle, Spring 1999

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    Vol. 40, No. 2 Table of Contents Poetry Eve\u27s DaughterSylvia Whippopage 1 When We Wore Canoes On Our ShouldersMandy Watsonpage 2 This Is Not A Poem About GrandpaJake Tolbertpage 3 Old relationshipsBrandi Kinneypage 5 UntitledErin Winnerpage 6 BraverySylvia Whippopage 6 deep dark closetNicole Smithpage 7 Belly EarthTara Coburnpage 9 The River and FireJake Tolbertpage 10 UntitledAutumn Williamspage 12 Action PotentialKim Evanspage 13 Chimerical (a song for children)D.M. Attrapepage 14 UntitledAutumn Williamspage 16 UntitledMatthew Armstrongpage 18 Building YouSylvia Whippopage 19 RunningKim Evanspage 20 Walking Jenn to WorkJake Tolbertpage 22 Looking InKim Hunterpage 23 Void Between Me and WisconsinMandy Watsonpage 24 Artwork UntitledWendy Finchpage 4 MeditationJennifer Lundpage 8 UntitledSteve Drakepage 15 MemoriesJennifer Lundpage 21 UntitledKathryn Kolasinskipage 25 Prose FoundKim Hunterpage 26 A Day in the Life of William Baxter, DriverDaniel Fitzgeraldpage 32https://thekeep.eiu.edu/vehicle/1072/thumbnail.jp

    The Vehicle, Spring 1999

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    Vol. 40, No. 2 Table of Contents Poetry Eve\u27s DaughterSylvia Whippopage 1 When We Wore Canoes On Our ShouldersMandy Watsonpage 2 This Is Not A Poem About GrandpaJake Tolbertpage 3 Old relationshipsBrandi Kinneypage 5 UntitledErin Winnerpage 6 BraverySylvia Whippopage 6 deep dark closetNicole Smithpage 7 Belly EarthTara Coburnpage 9 The River and FireJake Tolbertpage 10 UntitledAutumn Williamspage 12 Action PotentialKim Evanspage 13 Chimerical (a song for children)D.M. Attrapepage 14 UntitledAutumn Williamspage 16 UntitledMatthew Armstrongpage 18 Building YouSylvia Whippopage 19 RunningKim Evanspage 20 Walking Jenn to WorkJake Tolbertpage 22 Looking InKim Hunterpage 23 Void Between Me and WisconsinMandy Watsonpage 24 Artwork UntitledWendy Finchpage 4 MeditationJennifer Lundpage 8 UntitledSteve Drakepage 15 MemoriesJennifer Lundpage 21 UntitledKathryn Kolasinskipage 25 Prose FoundKim Hunterpage 26 A Day in the Life of William Baxter, DriverDaniel Fitzgeraldpage 32https://thekeep.eiu.edu/vehicle/1072/thumbnail.jp

    The Vinculin C-terminal Hairpin Mediates F-actin Bundle Formation, Focal Adhesion, and Cell Mechanical Properties

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    Vinculin is an essential and highly conserved cell adhesion protein, found at both focal adhesions and adherens junctions, where it couples integrins or cadherins to the actin cytoskeleton. Vinculin is involved in controlling cell shape, motility, and cell survival, and has more recently been shown to play a role in force transduction. The tail domain of vinculin (Vt) contains determinants necessary for binding and bundling of actin filaments. Actin binding to Vt has been proposed to induce formation of a Vt dimer that is necessary for cross-linking actin filaments. Results from this study provide additional support for actin-induced Vt self-association. Moreover, the actin-induced Vt dimer appears distinct from the dimer formed in the absence of actin. To better characterize the role of the Vt strap and carboxyl terminus (CT) in actin binding, Vt self-association, and actin bundling, we employed smaller amino-terminal (NT) and CT deletions that do not perturb the structural integrity of Vt. Although both NT and CT deletions retain actin binding, removal of the CT hairpin (1061–1066) selectively impairs actin bundling in vitro. Moreover, expression of vinculin lacking the CT hairpin in vinculin knock-out murine embryonic fibroblasts affects the number of focal adhesions formed, cell spreading as well as cellular stiffening in response to mechanical force
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