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This study examines cognitive planning in adolescents with Down syndrome (DS) following an 8-week assisted cycling therapy intervention. Forty-three participants were randomly assigned to assisted cycling (AC) (i.e., at least 30% faster than self-selected cadence accomplished by a motor), voluntary cycling (VC) (self-selected cadence), and no cycling (NC) control group. Both AC and VC rode a stationary bicycle three times/week, 30 minutes/session, for eight weeks in duration. Participants completed cognitive testing that assessed cognitive planning at the beginning (i.e., pretest) and end (i.e., posttest) of the 8-week intervention. Consistent with our hypothesis, the results showed that cognitive planning improved following eight weeks of cycling for the AC group. The same results were not seen for individuals in the VC or NC groups. Our results suggest that assisted cycling therapy may induce permanent changes in the prefrontal cortex in adolescents with DS.
ContributorsMillar, Kelsey Leann (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
This study examines the effectiveness of two modes of exercise on depression in adolescents with Down syndrome (DS). Thirty nine participants were randomly divided into a voluntary cycling group (VC) (i.e., self-selected cadence), an assisted cycling group (AC) (i.e., at least 30% faster than self-selected cadence accomplished by a motor), or a no exercise group (NC). In each cycling intervention the participant completed 30 minute cycling sessions, three times per week for a total of eight weeks. The Children's Depression Inventory II was administered prior to cycling (i.e., pretest) and after the eight week intervention (i.e., posttest). Although the data did not reach conventional levels of statistical significance, the results of the study demonstrated partial support for our hypothesis that adolescents with DS showed improvements in depression as measured by the Children's Depression Inventory II following assisted cycling, but not following eight weeks of voluntary cycling. In other words, eight weeks of moderate AC exercise demonstrated a trend for improved depression in adolescents with DS.
ContributorsMcgownd, Shana Leah (Author) / Ringenbach, Shannon (Thesis director) / Youngstedt, Shawn (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
Lithium-ion batteries are the predominant source of electrical energy storage for most portable electronics applications, including hybrid/electric vehicles, laptops, and cellular phones. However, these batteries pose safety concerns due to their flammability and tendency to violently ignite upon short circuiting or failing. Solid electrolytes are a current research development aimed at reducing the flammability and reactivity of lithium batteries. The compound Li7La3Zr2O12, or LLZO, exhibits satisfactory ionic conductivity in the cubic phase, which is normally synthesized via doping with Al. It has recently been discovered that synthesizing nanostructured LLZO can stabilize the cubic phase without the need for doping. Here nanostructured LLZO was formed using templating on various cellulosic fibers, including cotton fibers, printer paper, filter paper, and nanocellulose fibrils followed by calcination at 700-800 °C. The effect of templating material, calcination temperature, calcination time, and heating ramp rate on LLZO phase and morphology was thoroughly investigated. Templating was determined to be an effective method for controlling the LLZO size and morphology, and most templating experiments resulted in LLZO fibers or ligaments similar in size and morphology to the original template material. A systematic study on the various experimental parameters was performed, concluding that low calcination time and low ramp rate favored smaller ligament formation. Further, it was verified that cubic phase stabilization occurred for LLZO with ligaments of less than 1 micron on average without the use of doping. This research provides more information regarding the size dependence on cubic LLZO stabilization that has not been previously investigated in detail.
ContributorsGordon, Zachary Daniel (Author) / Chan, Candace K. (Thesis director) / Lin, Jerry (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Chemical Engineering Program (Contributor)
Created2015-05
Description
The prospect of anti-aging or life extension technology is controversial in biogerentology but deemed even by skeptical experts to warrant discussion. I discuss the justifications that the probability of life extension technology being developed in the near future is reasonably high and that this research justifies the time and money it receives. I investigate potential ethical and societal issues anti-aging technology might create. This paper addresses inequality of access, economic cost, changes in quality of life, the role of death in human life, if and how the technology should be regulated and how parties who choose not to undergo treatment can be fairly treated, even when they are a minority.
ContributorsGlesener, Julia Hannah (Author) / McGregor, Joan (Thesis director) / DeSerpa, Allan (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor)
Created2015-05
Description
Mortality of 1918 influenza virus was high, partly due to bacteria coinfections. We characterize pandemic mortality in Arizona, which had high prevalence of tuberculosis. We applied regressions to over 35,000 data points to estimate the basic reproduction number and excess mortality. Age-specific mortality curves show elevated mortality for all age groups, especially the young, and senior sparing effects. The low value for reproduction number indicates that transmissibility was moderately low.
ContributorsJenner, Melinda Eva (Author) / Chowell-Puente, Gerardo (Thesis director) / Kostelich, Eric (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Currently in synthetic biology only the Las, Lux, and Rhl quorum sensing pathways have been adapted for broad engineering use. Quorum sensing allows a means of cell to cell communication in which a designated sender cell produces quorum sensing molecules that modify gene expression of a designated receiver cell. While useful, these three quorum sensing pathways exhibit a nontrivial level of crosstalk, hindering robust engineering and leading to unexpected effects in a given design. To address the lack of orthogonality among these three quorum sensing pathways, previous scientists have attempted to perform directed evolution on components of the quorum sensing pathway. While a powerful tool, directed evolution is limited by the subspace that is defined by the protein. For this reason, we take an evolutionary biology approach to identify new orthogonal quorum sensing networks and test these networks for cross-talk with currently-used networks. By charting characteristics of acyl homoserine lactone (AHL) molecules used across quorum sensing pathways in nature, we have identified favorable candidate pathways likely to display orthogonality. These include Aub, Bja, Bra, Cer, Esa, Las, Lux, Rhl, Rpa, and Sin, which we have begun constructing and testing. Our synthetic circuits express GFP in response to a quorum sensing molecule, allowing quantitative measurement of orthogonality between pairs. By determining orthogonal quorum sensing pairs, we hope to identify and adapt novel quorum sensing pathways for robust use in higher-order genetic circuits.
ContributorsMuller, Ryan (Author) / Haynes, Karmella (Thesis director) / Wang, Xiao (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Objective: To assess and quantify the effect of state’s price transparency regulations (hereafter, PTR) on healthcare pricing.
Data Sources: I use the Healthcare Cost and Utilization Project’s Nationwide Inpatient Sample (NIS) from 2000 to 2011. The NIS is a 20% sample of all inpatient claims. The Manhattan Institute supplied data on the availability of health savings accounts in each state. State PTR implementation dates were gathered by Hans Christensen, Eric Floyd, and Mark Maffett of University of Chicago’s Booth School of Business by contacting the health department, hospital association, or website controller in each state.
Study Design: The NIS data was collapsed by procedure, hospital, and year providing averages for the dependent variable, Cost, and a host of covariates. Cost is a product of Total Charges within the NIS and the hospital’s Cost to Charge ratio. A new binary variable, PTR, was defined as ‘0’ if the year was strictly less than the disclosure website’s implementation date, ‘1’ for afterwards, and missing for the year of implementation. Then, using multivariate OLS regression with fixed effect modeling, the change in cost from before to after the year of implementation is estimated.
Principal Findings: The analysis estimates the effect of PTR to decrease the average cost per procedure by 7%. Specifications identify within state, within hospital, and within procedure variation, and reports that 78% of the cost decrease is due to within-hospital, within-procedure price discounts. An additional model includes the interaction of PTR with the prevalence of health savings accounts (hereafter, HSAs) and procedure electivity. The results show that PTR lowers costs by an additional 3 percent with each additional 10 percentage point increase in the availability of HSAs. In contrast, the cost reductions from PTR were much smaller for procedures more frequently coded as elective.
Conclusions: The study concludes price transparency regulations can lead to a decrease in a procedure’s costs on average, primarily through price discounts and slightly through lower cost procedures, but not due to patients moving to cheaper hospitals. This implies that hospitals are taking initiative and lowering prices as the competition’s prices become publically available suggesting that hospitals – not patients – are the biggest users of price transparency websites. Hospitals are also finding some ways to provide cheaper alternatives to more expensive procedures. State regulators should evaluate if a better metric other than charge prices, such as expected out-of-pocket payments, would evoke greater patient participation. Furthermore, states with higher prevalence of HSAs experience greater effects of PTR as expected since patients with HSAs have greater incentives to lower their costs. Patients should expect a shift towards plans that offer these types of savings accounts since they’ve shown to have a reduction of health costs on average per procedure in states with higher prevalence of HSAs.
Data Sources: I use the Healthcare Cost and Utilization Project’s Nationwide Inpatient Sample (NIS) from 2000 to 2011. The NIS is a 20% sample of all inpatient claims. The Manhattan Institute supplied data on the availability of health savings accounts in each state. State PTR implementation dates were gathered by Hans Christensen, Eric Floyd, and Mark Maffett of University of Chicago’s Booth School of Business by contacting the health department, hospital association, or website controller in each state.
Study Design: The NIS data was collapsed by procedure, hospital, and year providing averages for the dependent variable, Cost, and a host of covariates. Cost is a product of Total Charges within the NIS and the hospital’s Cost to Charge ratio. A new binary variable, PTR, was defined as ‘0’ if the year was strictly less than the disclosure website’s implementation date, ‘1’ for afterwards, and missing for the year of implementation. Then, using multivariate OLS regression with fixed effect modeling, the change in cost from before to after the year of implementation is estimated.
Principal Findings: The analysis estimates the effect of PTR to decrease the average cost per procedure by 7%. Specifications identify within state, within hospital, and within procedure variation, and reports that 78% of the cost decrease is due to within-hospital, within-procedure price discounts. An additional model includes the interaction of PTR with the prevalence of health savings accounts (hereafter, HSAs) and procedure electivity. The results show that PTR lowers costs by an additional 3 percent with each additional 10 percentage point increase in the availability of HSAs. In contrast, the cost reductions from PTR were much smaller for procedures more frequently coded as elective.
Conclusions: The study concludes price transparency regulations can lead to a decrease in a procedure’s costs on average, primarily through price discounts and slightly through lower cost procedures, but not due to patients moving to cheaper hospitals. This implies that hospitals are taking initiative and lowering prices as the competition’s prices become publically available suggesting that hospitals – not patients – are the biggest users of price transparency websites. Hospitals are also finding some ways to provide cheaper alternatives to more expensive procedures. State regulators should evaluate if a better metric other than charge prices, such as expected out-of-pocket payments, would evoke greater patient participation. Furthermore, states with higher prevalence of HSAs experience greater effects of PTR as expected since patients with HSAs have greater incentives to lower their costs. Patients should expect a shift towards plans that offer these types of savings accounts since they’ve shown to have a reduction of health costs on average per procedure in states with higher prevalence of HSAs.
ContributorsSabol, Joshua Lawrence (Author) / Reiser, Mark (Thesis director) / Ketcham, Jonathan (Committee member) / Dassanayake, Maduranga (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Supply Chain Management (Contributor)
Created2015-05
Description
The development of the Diabetic Physiological state is influenced by the Receptor for Advanced Glycation End Products (RAGE). This receptor was discovered in 1992, and the accumulation of research on this subject has been extensive. Structural characterization studies of the RAGE protein have shown that it is a transmembrane protein that binds a number of different motile ligands. The diversity of ligands that can attach to the binding domain is the primary factor that allows for RAGE to exhibit its wide-range effects on host cells. Two different studies were completed: one study dealt with the role of IAPP in beta cell death, and the second study was related to RAGE influence on cardiomyocytes and, more specifically, it was related to cardiac cell death. After the completion of the two studies, a comprehensive report was written for each topic. The two papers were merged into a single document. Molecular studies are important for understanding the underlying mechanisms that motivate pathophysiological presentation. In addition to a molecular understanding of the development of diabetes, a clinical research study was completed through the examination of appropriate literature sources. This clinical aspect allowed for the progression of different phases in the research process. A relationship between vinegar and lower plasma glucose was found. The exact mechanism behind this relationship will be studied in the future.
ContributorsGonzalez, Matthew Joseph (Author) / Johnston, Carol (Thesis director) / Collins, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
The OMFIT (One Modeling Framework for Integrated Tasks) modeling environment and the BRAINFUSE module have been deployed on the PPPL (Princeton Plasma Physics Laboratory) computing cluster with modifications that have rendered the application of artificial neural networks (NNs) to the TRANSP databases for the JET (Joint European Torus), TFTR (Tokamak Fusion Test Reactor), and NSTX (National Spherical Torus Experiment) devices possible through their use. This development has facilitated the investigation of NNs for predicting heat transport profiles in JET, TFTR, and NSTX, and has promoted additional investigations to discover how else NNs may be of use to scientists at PPPL. In applying NNs to the aforementioned devices for predicting heat transport, the primary goal of this endeavor is to reproduce the success shown in Meneghini et al. in using NNs for heat transport prediction in DIII-D. Being able to reproduce the results from is important because this in turn would provide scientists at PPPL with a quick and efficient toolset for reliably predicting heat transport profiles much faster than any existing computational methods allow; the progress towards this goal is outlined in this report, and potential additional applications of the NN framework are presented.
ContributorsLuna, Christopher Joseph (Author) / Tang, Wenbo (Thesis director) / Treacy, Michael (Committee member) / Orso, Meneghini (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Physics (Contributor)
Created2015-05
Description
The central goal of this thesis is to develop a practical approach to validating the correctness of SSA forms. Since achieving this goal is very involved for a general program, we restrict our attention to simple programs. In particular, the programs we consider are loop-free and are comprised of simple assignments to scalar variables, as well as input and output statements. Even for such a simple program, a full formal treatment would be very involved, extending beyond the scope of an undergraduate honors thesis.
ContributorsLusi, Dylan Patrick (Author) / Bazzi, Rida (Thesis director) / Fainekos, Georgios (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Computer Science and Engineering Program (Contributor)
Created2015-05