Strategies to support general education teachers serving students with mild to moderate disabilities

This action thesis project is submitted in partial fulfillment of the requirements for the Master of Arts in Education degree at California State University, Monterey Bay. The purpose of this action research project, Effective Strategies To Use In The Classroom, was to bring together my high school\u27s general educators and special education staff to work. together through collaboration to better serve the development and learning needs of students with learning disabilities. It examines the effectiveness of researched based instructional modifications and strategies to improve collaboration between general educators and special education teachers working as a team in support of the special needs student in the mainstream class setting. This action research project is a summary of this collaboration as a special education teacher with the focus on weekly analysis of student observations in the mainstream classroom. The collaboration team worked together to support special education students in a general education classroom setting. The weekly observations were analyzed by the volunteers and the researcher. The results revealed that the modifications by the teacher could support students to be active learners and engaged in the teacher made lesson plans. The Identification, Modifications and Strategies For Students With Disabilities booklet supported the teachers collaboration needs. The impact of this action research project improved the collaborative efforts of the general and special educators, by the implementation of the handbook so to serve all students

Measurements of nonmethane hydrocarbons in 28 United States cities

Between 1999 and 2005 a sampling campaign was conducted to identify and quantify the major species of atmospheric nonmethane hydrocarbons (NMHCs) in United States cities. Whole air canister samples were collected in 28 cities and analyzed for methane, carbon monoxide (CO) and NMHCs. Ambient mixing ratios exhibited high inter- and intra-city variability, often having standard deviations in excess of 50% of the mean value. For this reason, ratios of individual NMHC to CO, a combustion tracer, were examined to facilitate comparison between cities. Ratios were taken from correlation plots between the species of interest and CO, and most NMHCs were found to have correlation coefficients (r2) greater than 0.6, particularly ethene, ethyne and benzene, highlighting the influence of vehicular emissions on NMHC mixing ratios. Notable exceptions were the short-chain alkanes, which generally had poor correlations with CO. Ratios of NMHC vs. CO were also used to identify those cities with unique NMHC sources. © 2007 Elsevier Ltd. All rights reserved

Efficient illumination independent appearance-based face tracking

One of the major challenges that visual tracking algorithms face nowadays is being able to cope with changes in the appearance of the target during tracking. Linear subspace models have been extensively studied and are possibly the most popular way of modelling target appearance. We introduce a linear subspace representation in which the appearance of a face is represented by the addition of two approxi- mately independent linear subspaces modelling facial expressions and illumination respectively. This model is more compact than previous bilinear or multilinear ap- proaches. The independence assumption notably simplifies system training. We only require two image sequences. One facial expression is subject to all possible illumina- tions in one sequence and the face adopts all facial expressions under one particular illumination in the other. This simple model enables us to train the system with no manual intervention. We also revisit the problem of efficiently fitting a linear subspace-based model to a target image and introduce an additive procedure for solving this problem. We prove that Matthews and Baker’s Inverse Compositional Approach makes a smoothness assumption on the subspace basis that is equiva- lent to Hager and Belhumeur’s, which worsens convergence. Our approach differs from Hager and Belhumeur’s additive and Matthews and Baker’s compositional ap- proaches in that we make no smoothness assumptions on the subspace basis. In the experiments conducted we show that the model introduced accurately represents the appearance variations caused by illumination changes and facial expressions. We also verify experimentally that our fitting procedure is more accurate and has better convergence rate than the other related approaches, albeit at the expense of a slight increase in computational cost. Our approach can be used for tracking a human face at standard video frame rates on an average personal computer

γ-Linolenic acid increases expression of key regulators of lipid metabolism in human skeletal muscle cells

Control of skeletal muscle fat metabolism is regulated acutely through Peroxisome Proliferator Activated Receptor (PPAR) δ activation and its downstream intracellular targets. The purpose of this study was to determine whether fatty acids with high binding affinity for PPARδ can elevate the expression of genes related to fatty acid oxidation and indicators of mitochondrial biogenesis in cultured human skeletal myotubes. Myotubes were treated for 72 hours with one of four conditions: (i) Control (CON); (ii) Eicosapentaenoic acid (EPA 250μM); (iii) γ-linolenic acid (γ-LA 250μM); (iv) PPARδ Agonist (GW501516 10nM). Incubation with γ-LA induced increases in the gene expression of CD36 (p= 0.005), HADHA (p= 0.022) and PDK4 (p=0.025) in comparison with CON, with no further differences observed between conditions. Furthermore, intensity of MitoTracker® Red immunostaining in myotubes increased following incubation with γ-LA (p≤ 0.001) and EPA (p= 0.005) however these trends were not mirrored in the expression of PGC-1α as might be expected. Overall, γ-LA elevates levels the transcription of key intracellular regulators of lipid metabolism and transport in human myotubes, which may be clinically beneficial in the control of metabolic diseases

Myosin V passing over Arp2/3 junctions: branching ratio calculated from the elastic lever arm model

Myosin V is a two-headed processive motor protein that walks in a hand-over-hand fashion along actin filaments. When it encounters a filament branch, formed by the Arp2/3 complex, it can either stay on the straight mother filament, or switch to the daughter filament. We study both probabilities using the elastic lever arm model for myosin V. We calculate the shapes and bending energies of all relevant configurations in which the trail head is bound to the actin filament before Arp2/3 and the lead head is bound either to the mother or to the daughter filament. Based on the assumption that the probability for a head to bind to a certain actin subunit is proportional to the Boltzmann factor obtained from the elastic energy, we calculate the mother/daughter filament branching ratio. Our model predicts a value of 27% for the daughter and 73% for the mother filament. This result is in good agreement with recent experimental data.Comment: 9 pages, 7 figures, to appear in Biophysical Journa

Eye position and eye velocity integrators reside in separate brainstem nuclei.

Two types of central nervous system integrators are critical for oculomotor performance. The first integrates velocity commands to create position signals that hold fixation of the eye. The second stores relative velocity of the head and visual surround to stabilize gaze both during and after the occurrence of continuous self and world motion. We have used recordings from single neurons to establish that the 'position' and 'velocity' integrators for horizontal eye movement occupy adjacent, but nonoverlapping, locations in the goldfish medulla. Lidocaine inactivation of each integrator results in the eye movement deficits expected if horizontal eye position and velocity signals are processed separately. These observations also indicate that each brainstem compartment generates and stores these signals. Consequently, each integrator exhibits functional autonomy. Therefore, we propose that the intrinsic electrophysiological properties of the constituent neurons in each brainstem subnucleus may be sufficient for producing integrator rhythmicity

Elastic lever arm model for myosin V

We present a mechanochemical model for myosin V, a two-headed processive motor protein. We derive the properties of a dimer from those of an individual head, which we model both with a 4-state cycle (detached, attached with ADP.Pi, attached with ADP and attached without nucleotide) and alternatively with a 5-state cycle (where the power stroke is not tightly coupled to the phosphate release). In each state the lever arm leaves the head at a different, but fixed, angle. The lever arm itself is described as an elastic rod. The chemical cycles of both heads are coordinated exclusively by the mechanical connection between the two lever arms. The model explains head coordination by showing that the lead head only binds to actin after the power stroke in the trail head and that it only undergoes its power stroke after the trail head unbinds from actin. Both models (4- and 5-state) reproduce the observed hand-over-hand motion and fit the measured force-velocity relations. The main difference between the two models concerns the load dependence of the run length, which is much weaker in the 5-state model. We show how systematic processivity measurement under varying conditions could be used to distinguish between both models and to determine the kinetic parameters.Comment: 15 pages, 15 figures, to appear in Biophys.

Quantifying cell cycle regulation by tissue crowding

The spatiotemporal coordination and regulation of cell proliferation is fundamental in many aspects of development and tissue maintenance. Cells have the ability to adapt their division rates in response to mechanical constraints, yet we do not fully understand how cell proliferation regulation impacts cell migration phenomena. Here, we present a minimal continuum model of cell migration with cell cycle dynamics, which includes density-dependent effects and hence can account for cell proliferation regulation. By combining minimal mathematical modelling, Bayesian inference, and recent experimental data, we quantify the impact of tissue crowding across different cell cycle stages in epithelial tissue expansion experiments. Our model suggests that cells sense local density and adapt cell cycle progression in response, during G1 and the combined S/G2/M phases, providing an explicit relationship between each cell cycle stage duration and local tissue density, which is consistent with several experimental observations. Finally, we compare our mathematical model predictions to different experiments studying cell cycle regulation and present a quantitative analysis on the impact of density-dependent regulation on cell migration patterns. Our work presents a systematic approach for investigating and analysing cell cycle data, providing mechanistic insights into how individual cells regulate proliferation, based on population-based experimental measurements

Quantifying tissue growth, shape and collision via continuum models and Bayesian inference

Although tissues are usually studied in isolation, this situation rarely occurs in biology, as cells, tissues, and organs, coexist and interact across scales to determine both shape and function. Here, we take a quantitative approach combining data from recent experiments, mathematical modelling, and Bayesian parameter inference, to describe the self-assembly of multiple epithelial sheets by growth and collision. We use two simple and well-studied continuum models, where cells move either randomly or following population pressure gradients. After suitable calibration, both models prove to be practically identifiable, and can reproduce the main features of single tissue expansions. However, our findings reveal that whenever tissue-tissue interactions become relevant, the random motion assumption can lead to unrealistic behaviour. Under this setting, a model accounting for population pressure from different cell populations is more appropriate and shows a better agreement with experimental measurements. Finally, we discuss how tissue shape and pressure affect multi-tissue collisions. Our work thus provides a systematic approach to quantify and predict complex tissue configurations with applications in the design of tissue composites and more generally in tissue engineering