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Training Paraprofessionals to Implement Systematic Instruction Through a Pyramidal Approach Using Behavioral Skills Training
Get PDFTeaching students with intellectual and development disabilities (IDD) can often be a difficult and complex job. Teachers frequently rely on educational support staff or paraprofessionals to assist in the classroom in a variety of ways. However, paraprofessionals are unlikely to come into the classroom with the knowledge and skills needed to perform all duties that are asked of them. Paraprofessionals require on the job training and support to meet the needs of students. Teachers are unlikely to have had any preparation on how to train support staff. The purpose of this study was to examine the use of behavioral skills training (BST) within a pyramidal approach to training paraprofessionals. Paraprofessionals were trained to implement systematic instructional plans including a constant time delay response prompting procedure. Using a multiple probe design across participant triads, teachers, paraprofessionals, and students, the effects of the intervention package on the accuracy of paraprofessional implementation of systematic instructional plans and student progress were examined. Social validity was measured with pre- and post-surveys to examine the social impact of intervention goals, procedures, and effects on teachers and paraprofessionals as well as how it may have impacted students. This study successfully demonstrated the efficiency, feasibility, and acceptability of a pyramidal approach in the training of teachers to train five paraprofessionals to implement systematic instructional plans with CTD for students with significant IDD in a classroom setting, with data supporting paraprofessional generalization of behavior and maintenance of improvements following the conclusion of the study. The training intervention package used the evidence-based BST model including rationale, description, succinct written directions, demonstration, role-play, feedback, and practice to mastery. Implications for the training of teachers and paraprofessionals working with students with IDD are discussed
Design, Analysis and Control of Soft Wearable Devices Using Twisted String Actuators
No full textPhysical assistive robotic devices have demonstrated many desirable advantages in rehabilitation and augmentation, allowing for effective performance of activities of daily living (ADLs). Robotic rehabilitation, for instance, allows for accurate and efficient dynamic exercise routines where performance metrics can be easily retrieved. In human augmentation, wearable devices allows human beings to carry heavier loads for longer duration. However, it is challenging to create wearable robotic systems and devices that are inherently safe, compact, and can produce sufficient power and force. Existing robotic devices are often bulky, actuate limited degrees of freedom or produce limited force outputs. The large footprint of the devices usually lead to the devices being tethered either in the lab or in rehabilitation centers, limiting the duration of usage. In addition, active wearable devices that provide resistive capabilities to enable strength training have been difficult to develop. The properties of the wearable devices --- inherent safety, compactness, high force output --- is heavily driven by the choice of actuation mechanism. Twisted string actuators (TSAs) are appealing for wearable robotic applications because they are compliant, energy-efficient, capable of producing large translational force, and exhibit high power density. To utilize the properties of TSA, it is important to understand TSAs' key performance metrics to allow for ubiquitous usage. The performance analysis of TSAs is challenging due to the strong coupling between the TSA model parameters. It is important to compare TSA's performance to motor-based actuators, helping in understanding the trade-offs of TSAs compared to motor-based tendon-driven actuators. This dissertation first provides a theoretical model-based framework to analyze the performance of TSAs focusing on four metrics: contraction range, linear velocity, effective torque input and force output. The performance of the TSA is then compared to the spooled motor-tendon actuator (SMTA). SMTA is a motor based actuation approach that is similar in some regard to TSA. The results of the analysis and comparisons were then used as a basis to select to use TSAs for the actuation approach for the wearable devices in this work. Next, the design, characterization and open loop control of two devices that are driven by TSAs are described in detail. The two devices explored in detail are: 1) wearable glove and 2) wearable wrist orthosis. Specifically, the evolution of the wearable glove is presented in four versions, named a biomimetic robotic assistive glove (BRAG) v1, BRAG v2, Active Wearable Assistive and Resistive Device (AWARD) v1 and AWARD v2. In particular, BRAG v1 used only stiff strings while BRAG v2 and AWARD utilized stiff strings and compliant super coiled polymer strings for position sensing. In addition, the kinematic modeling, dynamic modeling and closed-loop control of AWARD is presented to demonstrate the different control strategies that can be used to achieve the unique capabilities in trajectory tracking. To allow for full state estimation of the finger motions without requiring tethered approaches, inertial measurement units, supercoiled polymer actuators, force sensitive resistors, encoders and motor current sensors were implemented, ensuring that the footprint and weight of the device is not affected drastically. Position control was implemented in the tendon space and also in the encoder space and demonstrated that desired trajectories were attained
Definitions and Determinants of Intradialytic Hypotension
No full textIntradialytic hypotension (IDH) is a frequent complication in hemodialysis (HD) patients that can be deadly. IDH is typically defined as a drop in blood pressure during HD treatment that may be associated with symptoms or need for an intervention. The etiology and pathophysiology of IDH is multifactorial and complex, respectively, and while effective treatments are available, they have notable drawbacks. This emphasizes the importance of strategies to prevent IDH rather than relying on acute treatment methods to manage blood pressure variability. This thesis reviews the current understanding of IDH and its etiologies, risk factors, definitions, and treatment options. A retrospective chart review was done in 44 patients to compare the different definitions of IDH to each other and how they relate to various risk factors. A novel definition of IDH was created for this study that was able to effectively categorize cases based on the severity of the drop in blood pressure. This definition helped describe the wide variability of IDH cases in this population, which may have potential for use in clinical and research applications
Ant-plant Mutualism as a Driver of Caterpillar Community Abundance, Diversity, and Specialization
No full textUnderstanding how species assemble into diverse communities" and why some communities are more diverse than other" is a central goal of ecology. Much of this complexity is likely due to the interplay among species interactions, environmental resources, and community traits at different scales, ranging from individuals to landscapes. Over the past few decades, ecologists have begun to realize the importance of mutualistic interactions as drivers of diversity. This dissertation investigates how mutualism responds to resource availability, and how and when such responses lead to changes in the diversity and composition of the communities in which mutualisms are embedded. Specifically, we examined variation in ant-plant protection mutualism strength across multiple scales and the consequences for the abundance and diversity of ant-plant herbivore communities. Ant-plant protection mutualisms, in which plants host colonies of ants that defend plants from herbivory, are an ideal system in which to examine the effects of mutualism on community assembly. In tropical regions, ant-plants sustain a diverse community of caterpillar herbivores, which allowed us to test how ant defense affects caterpillar community diversity, specialization, and species traits. By experimentally manipulating ant presence on ant-plants, we were able to separately examine the direct effects of resource availability on caterpillar community assembly and the indirect effects of resource availability that operate through ant-plant mutualisms. In Chapter 1, I examine ontogenetic variation in an ant-plant mutualism. Young ant-plants often lack ant colonies, potentially due to constraints imposed by size and corresponding resource pools. We examined whether juvenile ant-plants have alternative defense strategies prior to ant occupation. We surveyed juvenile ant-plants of the genus Cecropia across a variable landscape in northwest Costa Rica, measuring ant colonization rates, defensive leaf traits, spider visitation, and caterpillar herbivory. Our results suggest that smaller, uncolonized juvenile Cecropia are resource-constrained and are generally unable to invest in alternative defenses. Spider abundance was high on ant-uncolonized trees, yet spiders did not reduce herbivory. In contrast, tree size, light, and soil fertility increased leaf defensive phenolic compounds, which were effective at reducing herbivory. This chapter suggests that defense strategies in young Cecropia do not trade off, but instead juvenile trees invest more in all defense strategies and in growth when resources are high. In Chapter 2, I investigate whether ant-plant interactions can promote the diversity and specialization of herbivore communities in a seasonally dry tropical forest in Mexico. We used a factorial, common-garden experiment with the ant-plant Cordia alliodora to test how ant defense and water addition affected the diversity and specialization of caterpillar communities. We found that although ant defense reduced caterpillar abundance and diversity at the scale of individual trees, ant defense increased caterpillar community diversity at the scale of forest plots. The presence of ant defense increased caterpillar community evenness and the abundance of dietary-specialist caterpillar species. Because caterpillar species appeared to have different levels of tolerance to ants, and ant defensive activity varied strongly among the ant-defended trees, our results suggest that variation in ant defense at the scale of individual trees allows for niche partitioning among caterpillar species. Finally, in Chapter 3, I examine whether the effects of ant defense on caterpillar community diversity that we observed in Chapter 2 are altered by the size and component traits of caterpillar species pools. We established two common garden experiments with Cecropia in two distinct forests, a seasonally dry forest and a rainforest in Costa Rica. Experimental trees had ants either excluded or introduced. We found that, similar to our results in Chapter 2, in the seasonally dry forest, ants increased caterpillar community diversity and evenness at the scale of forest plots. However, ants did not affect the diversity of caterpillar communities in the rainforest. Ant defense was equally effective at reducing caterpillar densities in both forest plots, but the caterpillar species pool was larger and more even in the rainforest than in the dry forest. Ant defense primarily increased the evenness of caterpillar communities by reducing the most abundant, gregarious caterpillar species, which represented a smaller proportion of the rainforest species pool. This study suggests that regional-level species pool characteristics can determine the impact of species interactions on community assembly. This dissertation provides evidence that mutualism shapes community assembly. Moreover, these results suggest that mutualism is an essential driver of biodiversity. This dissertation is also a testament to the value of field experiments and the careful consideration of scale in multitrophic interactions
Impacts of discipline-specific morphology instruction on AP US History students' understanding of US Supreme Court Cases
Get PDFThis study assesses the impact of morphological awareness and its ability to assist secondary aged students in Advanced Placement US History with interpreting Supreme Court case law. The study included a demographic cross section of an urban high school n = 41). Results suggested morphology instruction may have had a positive impact on students’ production of morphologically complex words and the quality of their written summaries of United States Supreme Court Cases relating to the 14th Amendment of the United States’ Constitution. This work addresses the need for more research on the complex nature of academic language broadly and discipline specific language in social studies specifically. Because this study was completed by a classroom teacher and practitioner it offers, tentatively, pragmatic guidance for educators in bringing morphological awareness and its generative effect on academic language to the foreground. Finally, the study reveals practices that assist teachers with integrating their disciplinary content with the disciplinary language that will help students and their comprehension
The Effects of Reduced Glial Plasma Membrane Cholesterol on Actin Dynamics: Insights into Neuropathic Mechanisms
Get PDFDemyelinating neuropathy, a neurological disorder characterized by progressive loss of myelin, leads to impaired nerve function and sensory deficits. A cure or disease-modifying treatment for patients with demyelinating neuropathy is not available. Hence, investigating the subcellular mechanisms is crucial for therapeutic interventions. Genetic perturbations in Schwann cell proteins are responsible for these disorders. Cholesterol is an essential and rate-limiting lipid for myelin biogenesis, so understanding the interactions between disease-linked glial proteins and cholesterol is a topic of significance. Our previous studies demonstrated that the absence of peripheral myelin protein 22 (PMP22), a neuropathy-causing Schwann cell protein, disrupts cholesterol trafficking and alters the lipid moiety of the Schwann cell plasma membrane (PM). Earlier research have also shown that PMP22 is critical for myelination and cholesterol metabolism. Building upon these findings, our current study explores the intricate relationship between PM cholesterol deficiency and demyelinating neuropathy, specifically emphasizing subcellular actin dynamics. We hypothesize that reduced PM cholesterol alters the actin dynamics and enhances cholesterol uptake proteins and recycling pathways, thereby giving rise to Schwann cell dysfunctions. We used Sciatic nerves and cultured Schwann cells from genotyped wild-type (Wt) and PMP22-deficient mice and normal rats for the current study. To mimic the reduced cholesterol content of the PMP22-deficient glial PM in normal rat Schwann cells, we employed a pharmacological approach. We inhibited de novo cholesterol synthesis by simvastatin treatment (5 µM and 25 µM). By biochemical protein analyses and high-resolution confocal imaging, we detected a significant (p<0.001) increase in the abundance of filamentous actin (F-actin) compared to monomeric actin (G-actin) in cells with depleted PM cholesterol. In addition, statin exposure induced pronounced morphological changes in Schwann cells, leading to branching of the lamellipodia and dense F-actin bundles. The reduced cholesterol levels impair myelination in rat DRG cultures. The biochemical analysis revealed an increase in the expression of essential proteins involved in cholesterol uptake and recycling. Nerve lysates from 3-week-old PMP22-deficient and Trembler J (TrJ), neuropathic model for CMT1E, had elevated levels of F-actin, compared with Wt. By confocal imaging, we detected a pronounced accumulation of F-actin in the tomacula (myelin swellings) in the nerves of PMP22-deficit mice. The findings from the neuropathic samples were substantiated by unbiased proteomic studies from the PMP22-deficient and TrJ neuropathic model, which showed significant alterations in the expression of proteins involved in cholesterol uptake (p<0.05), and perturbations in the pathways associated with actin polymerization and depolymerization. Together, these findings provide novel insights for unraveling the link between the reduced PM cholesterol of neuropathic Schwann cells and subcellular alterations in actin dynamics
Should We Rescue the Ones Drowning in the Shallow End? Program Evaluation of a Lower-Risk/Lower-Need Drug Court
Get PDFThe purpose of this case study was to evaluate a lower-risk/lower-need (LRLN) drug court program, the Cobb County Intermediate Drug Court Program (IDC), to determine its effectiveness in promoting participant recovery and reducing recidivism. This thesis will review the Cobb County, Georgia felony adult Intermediate Drug Court Program over its four-year history (January 2017-January 2021). The relative success and effectiveness of this program is compared with the effects of an eighteen-month, highrisk/high-need (HRHN) treatment court, the Cobb County Adult Drug Treatment Court (ADTC). This qualitative and quantitative program evaluation study assesses the impact of a twelve-month, court-directed program on the overall recovery and rate of recidivism of low or intermediate risk/need level drug court participants during the program and within three years of graduation from the program. Success rates have been measured by graduation rates, amount of time (number of days) in each program, and recidivism rates within the first three years after graduation from the program (or before graduation). This qualitative and quantitative program evaluation study assesses the impact of a twelve-month, court-directed program on the overall recovery and rate of recidivism of low or intermediate risk/need level drug court participants during the program and within three years of graduation from the program. Success rates have been measured by graduation rates, amount of time (number of days) in each program, and recidivism rates within the first three years after graduation from the program (or before graduation). In addition, recidivism rates of the eighteen-month Cobb County ADTC program are compared with IDC results for a sampling of program participants identified in the lowor intermediate-risk levels. Similar recidivism rates between these groups may validate the necessity for other, less intensive programs for low- to intermediate-risk participants. If similar results can be obtained in such less intensive program tracks for lower-risk participants, both the program and the participants benefit. Benefits include preservation of resources for the program and achievement of similar results for program participants in a shorter timeframe while achieving a desirable avoidance of overtreatment. Within each program, data were also compared to ascertain whether varying results were obtained in either program based upon other factors potentially affecting graduation and recidivism, including gender, age, adjudication status, and drug of choice. These objective factors were determined from data within the courts' files with the exception of drug of choice which was determined by the participants' subjective report. Case study/program evaluation involved a secondary data analysis of archival data created over the course of the four-year history of the IDC and data obtained from the ADTC. This data was found in drug court, court, and law enforcement records. Recidivism data was obtained from law enforcement records and public data searches. The results of this study will help jurisdictions evaluate the need for further intermediate-level drug court programs to augment the existing high-risk/high-need programs statewide. Evaluation of this program will also inform the local community and the Superior Court in directing critical funds and manpower and other valuable resources within the county
Waterfall erosion and alteration of river form
No full textBedrock rivers are critical to landscape evolution because they transmit tectonic signals throughout the landscape, set the base level for hillslope erosion and remove eroded sediment. Because of their role at the center of landscape erosion, bedrock rivers can provide insight into the climatic and tectonic conditions within a drainage. In particular, bedrock river steepness can provide information about the relative erosion rate of a channel, and bedrock channel width can contain clues regarding sediment flux. However, it is possible that these signals may be altered due to waterfalls which are common features in steep bedrock rivers. While many waterfalls form as a part of a transient knickzone (an oversteepened river reach created through a change in external conditions), some waterfalls are known to self-form when Froude supercritical flows develop in steep bedrock channels. And although previous work has developed an understanding of knickzones retreat through a basin, it is not clear whether waterfalls which are not a part of a knickzones follow the same rules. Specifically, it is important to understand whether self-formed waterfalls are capable of altering long profile form and channel morphology independent from the influence of knickzone dynamics. This research addresses this knowledge gap by investigating waterfalls in many different settings, and through different methods. In Chapter 2, I use a finite difference model to examine how self-formed waterfalls alter longitudinal profiles. I find that self-formed waterfalls may create a reach with a constant slope in dynamic equilibrium, or alternatively, self-formed knickpoints, depending on the speed of waterfall erosion. Furthermore, I find these results consistent with some natural river profiles. In Chapter 3, I investigate how quickly waterfall-rich channels erode using 10-Be analysis. I find that waterfall-rich channels erode faster than the rest of the landscape on average and erode faster with increasing concentration of waterfalls. Through comparing my results with a physics-based model, I also find that waterfalls may erode slowly under conditions such as high sediment flux, large grain sizes, and low discharge. In Chapter 4, I extract channel widths and waterfall locations from lidar and use the data to show that waterfalls locally constrict channel width. I also demonstrate that the length scale of waterfall influence below a waterfall grows with increasing drainage areas, indicating an increase in waterfall erosion rates. Overall, this research provides a detailed look at the physical reality of waterfall erosion, which can be used to better understand knickzones dynamics, and channels in steady state
Exploring the Neural Foundations and Causal Mechanisms of Real-World Cognition
No full textThe brain evolved to perceive and to facilitate interaction with an environment consisting of real, three-dimensional objects, an environment in which humans and animals still live most of their lives. However, our knowledge of visual cognition and visual neuroscience is based predominantly on studies that have used 2-D images as visual stimuli. If behavioral and brain responses to real objects and 2-D stimuli differ, then many of the traditional frameworks of cognitive neuroscience may need to be reevaluated. Recent studies have in fact shown that real objects elicit different behavioral responses than images in many cognitive domains, including perception, action, memory, and attention. However, neither the neural correlates underlying these differences, nor the causal mechanisms responsible for these differences, have been extensively investigated. Across three studies, this dissertation explores the neural and causal bases of real-object effects. In the first study, I use fMRI to compare the effects of distance and size on brain representations of real objects vs. printed pictures. In the second study, I use fMRI to compare the neural correlates of recognition memory for real objects vs. computer images. In the third study, I use eye tracking to compare gaze patterns for real objects, 2-D images, and 3-D images. My behavioral data shows that real objects are better remembered than images, and that gaze towards real objects, compared to both 2-D and 3-D images, gravitates more towards object parts relevant to the current task. My neuroimaging data show that the functions of the dorsal and ventral visual pathways may be more integrated during viewing of real objects than of pictures, and that regions supporting memory retrieval and object-action associations respond differently during recognition memory of real objects vs. images. My results suggest that the different responses to real objects vs. images depend largely on the potential of real objects for genuine physical interaction. These findings have major translational implications in an era of increased screen-time dominated by artificial, digital objects. These findings also reveal the limitations of 2-D experimental stimuli and highlight the value of real-world experimental stimuli in providing a comprehensive characterization of naturalistic visual cognition