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Folate Metabolism in Yeast Cell Cycle and Mouse Healthspan
No full textFolate, or vitamin B9, is a key component in one-carbon (1C) metabolism that supports precursor molecules required for growth and development. Folate is found in some natural foods, and its synthetic form is called folic acid (FA). Insufficient folate levels in pregnant women cause fetal neural tube defects (NTDs) and other birth defects. To increase folate intake, FDA mandated in 1998 that FA be included in fortified processed food. My dissertation work queries aspects of 1C enzyme roles in cell cycle progression and dietary folate���s impact on healthspan in aging mice. In my first dissertation project, I used budding yeast S. cerevisiae as a cell cycle model. I measured levels of three 1C enzymes during the cell cycle to confirm previous predictions of their translational control. Next, I used individual knockout strains to determine individual 1C enzyme effects on cell size, cell cycle progression, and metabolome profiles. These results contribute to the understanding of processes in cell growth and division. In my second dissertation project, I introduced a completely folate- and choline-deficient (FC-) diet in aged mice of a long-lived wildtype strain. Standardized phenotyping protocols were used to evaluate healthspan before the diet switch and periodically after until death. I show that healthspan phenotypes either improved or did not change on the FC- diet. This study serves as a preliminary test to re-evaluate FA fortification in an aging general population. Overall, my dissertation work unveils folate cycle impacts at both cellular and physiological levels that invite more questions to answer
Zenji: Heuristic Algorithms to Identify and Correct Common Japanese Kanji Handwriting Mitakes
Get PDFThe kanji writing system���tens of thousands of logographic Japanese characters originating from China���is by far the most complex of the three Japanese scripts. Kanji present a unique challenge for English-speaking Japanese learners, as they lack an equivalent in western tongues. Whether studying in a classroom or independently, Japanese language learners are often exposed to mnemonics or other techniques to aid in the memorization of these symbols. However, the classroom setting presently provides a unique opportunity for learners to hand-write the characters and receive feedback on their writing. The difficulty and lack of feedback on handwriting for independent learners discourages the practice of hand-writing kanji, which can stunt the learning process. This paper introduces Zenji, a system of heuristic algorithms to analyze student handwriting of kanji. Zenji provides a lightweight solution that may easily be run on students��� personal computing devices and naturally integrated into existing mobile spaced-repetition solutions for kanji learning. The Zenji system provides users overall and per-stroke numeric, visual, and written feedback on various metrics, focusing on common mistakes. In validation testing, Zenji���s feedback proved to be highly accurate across the categories that it assesses, highlighting user errors and combining a classroom-like learning experience with the flexibility of independent study
Simulation of a Flow System Designed for 3-D Imaging of Microcarrier-Based Cell Cultures
No full textHuman mesenchymal stem cells (hMSCs) have been found to be a potential treatment for heart disease, diabetes, and stroke. As the prevalence of stem cell therapies increases, methods of production must be ready to meet this higher level of demand. This research focuses on the development of a 3D imaging flow cytometry (IFC) system for assessing the viability of hMSCs. This IFC system poses many benefits over traditional stem cell assessment procedures such as greater throughput, increased consistency, and decreased labor requirements. The focus of this paper will be on creating a flow system that moves the microcarriers through the imaging plane and determining its efficacy. The flow system is run through a Raspberry Pi and can be fully operated remotely. This allows the user to set parameters for the fluid flow such as flow rate and duration and start the system at any time. The overall system will also be equipped with a photodiode that triggers the camera as the microcarriers approach the imaging field, preventing extraneous photo capturing and saving drive storage and data processing time. The photodiode detection system is currently still under development. The maximum flow rate of the system is 3000 ��L/min through the 0.9 x 0.9 mm microfluidic channel where the images are captured. Computational tests have demonstrated the flow system���s ability to achieve ideal conditions for imaging like steady, laminar flow even at high output levels. While the other components are still under development, these results show that a 3D IFC system with microcarrier-based cell cultures and deep learning image analysis may be a viable solution for the monitoring of hMSCs during production
