AN INVESTIGATION OF THE STUDENT USE OF TACTUAL LEARNING-STYLE PREFERENCE TECHNIQUES AND STUDENT SELF-PERCEPTION

Students across the United States are routinely administered state assessments to measure academic progress in the grade level they have been assigned. These tests have become the measure of a district or school\u27s ability to meet Adequate Yearly Progress (AYP). Many students are not able to attain the expected of level of proficiency. In 20II in rural high-need school districts in New York State,43 percent of third through fifth grade students did not make AYP in mathematics (non-AYP students; New York State Education Department, 20ll). The Common Core Standards have been implemented to ensure that students graduating from high school are prepared to succeed in college or a career (Common Core, 2014). Students who are unable to show proficiency in elementary school arc at risk of dropping out of school prior to graduation. The purpose of this exploratory study was to compare the learning-style preferences of fifth grade students who achieved adequate yearly progress in mathematics and those who did not achieve AYP. The study investigated non-AYP students\u27 use of tactual learning-style preference strategies and the perceptions of these students in the use of tactual materials. Fifth grade students in this study were administered the Learning Style: Clue to You! (LSCY), a learning-style assessment used to determine preferences and strengths for learning. Assessment data were used to determine the similarities and differences between AYP and non-AYP students with a Chi-square Crosstabulation test. The learning-style elements for auditory learning and time of day revealed significance between the groups. Further analyses were completed with a Chi-square Goodness of Fit test to determine the learning-style preferences of non-AYP fifth grade students. Eleven of the 22 elements revealed significance within the group in the strands related to environmental, emotional, sociological, and physiological preferences. Prescriptive training was provided to a select group of non-AYP students in using learning strategies that matched their tactual learning-style preference. Qualitative data were collected through the use of student portfolios, interviews, a focus group, and student self-reflections. Semi-structured interviews and a focus group were conducted to explore the use of the learning-style profile and the application of tactual strategies with mathematics. These data were examined to determine a better understanding of the connection between learning styles and students\u27 perceptions. Analysis of the qualitative data revealed that students were able to identify preferences related to their learning style and students had an increased awareness of themselves as a learner

Cell viscoelasticity is linked to fluctuations in cell biomass distributions.

The viscoelastic properties of mammalian cells can vary with biological state, such as during the epithelial-to-mesenchymal (EMT) transition in cancer, and therefore may serve as a useful physical biomarker. To characterize stiffness, conventional techniques use cell contact or invasive probes and as a result are low throughput, labor intensive, and limited by probe placement. Here, we show that measurements of biomass fluctuations in cells using quantitative phase imaging (QPI) provides a probe-free, contact-free method for quantifying changes in cell viscoelasticity. In particular, QPI measurements reveal a characteristic underdamped response of changes in cell biomass distributions versus time. The effective stiffness and viscosity values extracted from these oscillations in cell biomass distributions correlate with effective cell stiffness and viscosity measured by atomic force microscopy (AFM). This result is consistent for multiple cell lines with varying degrees of cytoskeleton disruption and during the EMT. Overall, our study demonstrates that QPI can reproducibly quantify cell viscoelasticity

Ampk regulates IgD expression but not energy stress with B cell activation.

Ampk is an energy gatekeeper that responds to decreases in ATP by inhibiting energy-consuming anabolic processes and promoting energy-generating catabolic processes. Recently, we showed that Lkb1, an understudied kinase in B lymphocytes and a major upstream kinase for Ampk, had critical and unexpected roles in activating naïve B cells and in germinal center formation. Therefore, we examined whether Lkb1 activities during B cell activation depend on Ampk and report surprising Ampk activation with in vitro B cell stimulation in the absence of energy stress, coupled to rapid biomass accumulation. Despite Ampk activation and a controlling role for Lkb1 in B cell activation, Ampk knockout did not significantly affect B cell activation, differentiation, nutrient dynamics, gene expression, or humoral immune responses. Instead, Ampk loss specifically repressed the transcriptional expression of IgD and its regulator, Zfp318. Results also reveal that early activation of Ampk by phenformin treatment impairs germinal center formation but does not significantly alter antibody responses. Combined, the data show an unexpectedly specific role for Ampk in the regulation of IgD expression during B cell activation

Quantification of Biomass and Cell Motion in Human Pluripotent Stem Cell Colonies

Abstract Somatic cell reprogramming to pluripotency requires an immediate increase in cell proliferation and reduction in cell size. It is unknown whether proliferation and biomass controls are similarly coordinated with early events during the differentiation of pluripotent stem cells (PSCs). This impasse exists because PSCs grow in tight clusters or colonies, precluding most quantifying approaches. Here, we investigate live cell interferometry as an approach to quantify the biomass and growth of HSF1 human PSC colonies before and during retinoic acid-induced differentiation. We also provide an approach for measuring the rate and coordination of intracolony mass redistribution in HSF1 clusters using live cell interferometry images. We show that HSF1 cells grow at a consistent, exponential rate regardless of colony size and display coordinated intracolony movement that ceases with the onset of differentiation. By contrast, growth and proliferation rates show a decrease of only ∼15% decrease during early differentiation despite global changes in gene expression and previously reported changes in energy metabolism. Overall, these results suggest that cell biomass and proliferation are regulated independent of pluripotency during early differentiation, which is distinct from what occurs with successful reprogramming

Nonlinear Dynamics of Ion Concentration Polarization in Porous Media: The Leaky Membrane Model

The conductivity of highly charged membranes is nearly constant, due to counter-ions screening pore surfaces. Weakly charged porous media, or "leaky membranes", also contain a significant concentration of co-ions, whose depletion at high current leads to ion concentration polarization and conductivity shock waves. To describe these nonlinear phenomena the absence of electro-osmotic flow, a simple Leaky Membrane Model is formulated, based on macroscopic electroneutrality and Nernst-Planck ionic fluxes. The model is solved in cases of unsupported binary electrolytes: steady conduction from a reservoir to a cation-selective surface, transient response to a current step, steady conduction to a flow-through porous electrode, and steady conduction between cation-selective surfaces in cross flow. The last problem is motivated by separations in leaky membranes, such as shock electrodialysis. The article begins with a tribute to Neal Amundson, whose pioneering work on shock waves in chromatography involved similar mathematics

Fast synthesis of platinum nanopetals and nanospheres for highly-sensitive non-enzymatic detection of glucose and selective sensing of ions

Novel methods to obtain Pt nanostructured electrodes have raised particular interest due to their high performance in electrochemistry. Several nanostructuration methods proposed in the literature use costly and bulky equipment or are time-consuming due to the numerous steps they involve. Here, Pt nanostructures were produced for the first time by one-step template-free electrodeposition on Pt bare electrodes. The change in size and shape of the nanostructures is proven to be dependent on the deposition parameters and on the ratio between sulphuric acid and chloride-complexes (i.e., hexachloroplatinate or tetrachloroplatinate). To further improve the electrochemical properties of electrodes, depositions of Pt nanostructures on previously synthesised Pt nanostructures are also performed. The electroactive surface areas exhibit a two order of magnitude improvement when Pt nanostructures with the smallest size are used. All the biosensors based on Pt nanostructures and immobilised glucose oxidase display higher sensitivity as compared to bare Pt electrodes. Pt nanostructures retained an excellent electrocatalytic activity towards the direct oxidation of glucose. Finally, the nanodeposits were proven to be an excellent solid contact for ion measurements, significantly improving the time-stability of the potential. The use of these new nanostructured coatings in electrochemical sensors opens new perspectives for multipanel monitoring of human metabolism

Stabilization of Ion Concentration Polarization Using a Heterogeneous Nanoporous Junction

We demonstrate a recycled ion-flux through heterogeneous nanoporous junctions, which induce stable ion concentration polarization with an electric field. The nanoporous junctions are based on integration of ionic hydrogels whose surfaces are negatively or positively charged for cationic or anionic selectivity, respectively. Such heterogeneous junctions can be matched up in a way to achieve continuous ion-flux operation for stable concentration gradient or ionic conductance. Furthermore, the combined junctions can be used to accumulate ions on a specific region of the device.Korea Research Foundation (Grant MOEHRD: KRF-2007-331-D00040)Korean Science and Engineering Foundation (Grant MOST: R01-2007-000-20675-0)Korea Research Foundation (Grant MOEHRD: KRF-J03000)National Research Foundation of Korea (Grant NRF-2009- 352-D00034)National Institutes of Health (U.S.) (EB005743)National Science Foundation (U.S.). (CBET-0347348