Modeling Action Potential Propagation During Hypertrophic Cardiomyopathy Through a Three-Dimensional Computational Model

Hypertrophic cardiomyopathy (HCM) is the most common monogenic disorder and the leading cause of sudden arrhythmic death in children and young adults. It is typically asymptomatic and first manifests itself during cardiac arrest, making it a challenge to diagnose in advance. Computational models can explore and reveal underlying molecular mechanisms in cardiac electrophysiology by allowing researchers to alter various parameters such as tissue size or ionic current amplitudes. The goal of this thesis is to develop a computational model in MATLAB and to determine if this model can accurately indicate cases of hypertrophic cardiomyopathy. This goal is achieved by combining a three-dimensional network of the bidomain model with the Beeler-Reuter model and then by manually varying the thickness of that tissue and recording the resulting membrane potential with respect to time. The results of this analysis demonstrated that the developed model is able to depict variations in tissue thickness through the difference in membrane potential recordings. A one-way ANOVA analysis confirmed that the membrane potential recordings of the different thicknesses were significantly different from one another. This study assumed continuum behavior, which may not be indicative of diseased tissue. In the future, such a model might be validated through in vitro experiments that measure electrical activity in hypertrophied cardiac tissue. This model may be useful in future applications to study the ionic mechanisms related to hypertrophic cardiomyopathy or other related cardiac diseases

Expected Number of Distinct Subsequences in Randomly Generated Binary Strings

When considering binary strings, it's natural to wonder how many distinct subsequences might exist in a given string. Given that there is an existing algorithm which provides a straightforward way to compute the number of distinct subsequences in a fixed string, we might next be interested in the expected number of distinct subsequences in random strings. This expected value is already known for random binary strings where each letter in the string is, independently, equally likely to be a 1 or a 0. We generalize this result to random strings where the letter 1 appears independently with probability $\alpha \in [0,1]$. Also, we make some progress in the case of random strings from an arbitrary alphabet as well as when the string is generated by a two-state Markov chain.Comment: 10 page

Universal and Near-Universal Cycles of Set Partitions

We study universal cycles of the set ${\cal P}(n,k)$ of $k$-partitions of the set $[n]:=\{1,2,\ldots,n\}$ and prove that the transition digraph associated with ${\cal P}(n,k)$ is Eulerian. But this does not imply that universal cycles (or ucycles) exist, since vertices represent equivalence classes of partitions! We use this result to prove, however, that ucycles of ${\cal P}(n,k)$ exist for all $n \geq 3$ when $k=2$. We reprove that they exist for odd $n$ when $k = n-1$ and that they do not exist for even $n$ when $k = n-1$. An infinite family of $(n,k)$ for which ucycles do not exist is shown to be those pairs for which $S(n-2, k-2)$ is odd ($3 \leq k < n-1$). We also show that there exist universal cycles of partitions of $[n]$ into $k$ subsets of distinct sizes when $k$ is sufficiently smaller than $n$, and therefore that there exist universal packings of the partitions in ${\cal P}(n,k)$. An analogous result for coverings completes the investigation.Comment: 22 page

Healthy Food Access and Education

Providing resources and educational materials to families about healthy foodshttps://scholarworks.uvm.edu/fmclerk/2000/thumbnail.jp

Characteristic themes in the American short story

Thesis (M.A.)--Boston University, 1938. This item was digitized by the Internet Archive

Past environmental factors found in veterans with certification of disability for discharge

Thesis (M.S.)--Boston University, 1944. This item was digitized by the Internet Archive

Validation of current body composition estimation equations for men over 60 years of age

This study compared five skinfold equations for body composition (Jackson & Pollock\u27s Sum of 7 {dollar}\{{dollar}JP7{dollar}\}{dollar} and Sum of 3 {dollar}\{{dollar}JP3{dollar}\}{dollar}; Jackson & Pollock\u27s Sum of 4 {dollar}\{{dollar}Y4{dollar}\}{dollar} and Sum of 3 {dollar}\{{dollar}Y3{dollar}\}{dollar} for the YMCA, and Durnin and Womersley\u27s Sum of 7 {dollar}\{{dollar}DW{dollar}\}){dollar} with percent fat obtained from underwater weighing. Subjects were ninety-seven adult males aged 60-80 years. Skinfold measurements were taken with Lange calipers and underwater weight (UWW) was determined in a seated position utilizing a load cell system with residual volume (RV) measured at the time of weighing; The skinfold equations achieved a mean correlation of.74 with underwater weighing. JP7 yielded the highest correlation (.78) and DW the lowest (.72). A 1RM-ANOVA indicated that all five equations produced significantly different results than UWW. The data showed that these equations are not as valid with the present study\u27s population as with those from which the equations were derived

Total synthesis of barettin: Model study of specialized aldol condensation to directly access diketopiperazine targets

We synthesized (±)-(Z)-barettin, a potent anti-biofouler, with 31 % yield as a mono-TFA salt over seven steps with only one chromatographic separation. The route is efficient, proceeds under mild conditions, and is optimized to reduce formation of undesired byproducts otherwise seen in the aldol condensations and the Boc protection. Our route enables us to 1) utilize a DKP condensation with an unstable aliphatic aldehyde, 2) showcase how the DKP condensation provides direct access to a bioactive scaffold, and 3) suggest a simple, high yielding route to barettin and analogues consisting of only one chromatographic separation

Large Scale Specimen Design and Creep Analysis for Nuclear Containment Concrete Walls

Nuclear containment facilities in the US are quickly approaching the end of their design lives. However, due to the need for energy and the staggering cost of constructing new facilities, the industry is hoping to push the service lives of existing structures upwards of 80 years. Therefore, it is necessary to identify the risks associated with long term use of such facilities. Since these structures are typically post-tensioned concrete containment vessels, one of the main concerns is the phenomenon known as concrete creep. This study focuses on observing the effects of concrete creep by constructing three large scale reinforced concrete wall sections to model variable contributing factors to the creep phenomenon. Concrete strains and temperatures through the thicknesses of the specimens, as well as the strain in select post-tensioning bars used to apply specimen stresses, are measured. From six months of measured data since post-tensioning, there were noticeable changes in the post-tensioning bar strains and concrete strains, which is most likely the result of changes in ambient temperature in the winter months, and possibly creep. To confirm the field data values, a simple, static finite element model was developed to simulate concrete strain changes as a result of post-tensioning. The model confirmed the preliminary field data was closely related to the numerical estimations, with deviations stemming from the lack of complexity of the model. The model can be easily modified in the future to include concrete creep and other important physical occurrences that the specimens undergo in practical applications. This research, in conjunction with materials tests being conducted in the lab by other students, will provide the framework for a powerful predictive creep model to be developed to analyze the expected lifespans of such existing structures