Wheaton College (MA) Digital Repository
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Preliminary study on the effect of cortisol on Gallus gallus Schwann cell myelination
No full text11 pages; 3 illustrations
Vapor Pressure Measurements of Pentane at Low Temperatures (-160 ºC to -50 ºC) using Cost-Effective Equipment
No full text42 leaves; illustrations.Includes bibliographical references (leaves 41-42).Certain extraterrestrial environments like ocean worlds and icy satellites, are promising astrobiological places that can host a plethora of organic compounds trapped in their ices. The vapor pressure curves derived from theoretical calculations and experimental measurements aid in the construction of phase diagrams, which can help us better understand the behavior of organic molecules under the extraterrestrial conditions that aren’t found on Earth. In this work, a novel method was developed to measure vapor pressures at low temperatures (-160 ºC to -50 ºC) using cost-effective instrumentation. Following the development of the approach, vapor pressure of n-pentane was measured at temperatures ranging from -160 ºC to -50 ºC. Very few experimental measurements exist for n-pentane and for many other organics, especially at low temperatures. Vapor pressure measurements from the novel experimental procedure were difficult to compare to theoretical n-pentane phase diagrams; but, were comparable to past experimental measurements for n-pentane. The calculated enthalpy of fusion value from experimental run 1 was almost one order of magnitude lower as compared to literature value. The calculated enthalpy of vaporization value from experimental run 1 was about one and half orders of magnitude lower than the literature value. The development of this approach to measure vapor pressures at low temperatures is a first step to design a system that can be used for organic liquids samples (like n-pentane) using cost-effective equipment. It also has the potential to be further modified and enhanced to also measure vapor pressure of gaseous organics at low temperatures.Abstract -- Introduction -- Titan Atmospheric and Surface Chemistry -- Trapped Organics on Titan -- Preliminary Phase Diagrams for Titan’s Surface Molecules -- Why Pentane? -- Methods -- Equipment -- Procedure -- Initial set-up -- Clean-up -- Detailed Notes for Procedure -- Validation of Temperature Probe -- Inserting the Temperature probe in the rubber stopper -- Flush (Vacuum) -- Testing for Seals - Cold Bath Preparation -- Submersion and reaching the ideal temperature -- Sample preparation and delivery -- Measurements -- Troubleshooting the setup -- Results -- Experimental Run 1: VP of Pentane -- Experimental Run 2: VP of Pentane -- Discussion -- Clausius-Clapeyron Relationship -- Comparison with Literature -- Experimental Design Notable Successes -- Future Research -- Limitations -- Next steps -- Reference
Rushlight: Fall 2021 - Spring 2022
Full text linkGlowingIf OnlyI Lost my Father to Jungle GoldStargazinga light in the darkNights That Get Dark Too QuicklyZach, 2021The small things that emergeOffice AnxietyWho You AreThe Cape Cod FarmerNooseDetrioratingThink Wide OpenAss LifeDirty Laundry, 2022FatigueRaw-selfRequiemRememberTyphoonsI Stand Up Next to a Mountain and Chop it Down With the Edge of my HandRevealEternityExploreSo here we are today!Reflectiondouble exposure holgaJust Another Stage AdaptationThe Traveling Blue ChairSeven Months into NineteenGrowthFloating-Point NanShort GlorysneakThe No-Contact RuleforwardDrift Through DaylightCup of DaisesHotsweetUntitledSlice of Orange LightForbidden FruitProjector SeriesLoce According to me and The Laws of Physicsabandonded sunsetEncroaching DarknessSeagull Landing in Waterworry wormSucculentsMirrored HeartIndependenty Thought PatternsUntitled6 AM 2021Someonewinter is a dark bedconcert in the apartmentOrange PetalsNECTARINESInmigranteEccentricregarding the tiny sculptures on the grassneon-lightsEntry 07I'm trying to make sense of it but am failing desperatelyThe Weight We Carr
Derivation and meaning: a computer-assisted investigation into etymological and semantic connections in English
No full text86 leaves; illustrations.Includes bibliographical references (leaves 49-51).An important subfield within philology is etymology, the study of words and their origins. This thesis combines philology and etymology with computational techniques to quantify the large-scale relationships between words in the English language. Specifically, using English headwords, definitions, and etymology data from Wiktionary, graphs were constructed of English words and their relationships in etymology and meaning. These graphs were then examined to test for any correlation between etymological and semantic associations in the graphs. No clear correlation was found, meaning relationships in etymology are not a reliable guide to relationships in meaning in the English language.Abstract -- Introduction -- Background -- Methods -- Overview -- Preprocessing Definition Data -- Identification of Semantic Links -- Identification of Etymological Links -- Word-to-Word Distance Calculation -- Random Sampling -- Sample Size Determination -- Comparing Word-to-Word Distances -- Testing Removal of Roots and Affixes -- Graph Visualization and Identification of “Dictionary Stop Words” -- Statistical Tests -- Results -- Graph Visualization -- Sample Size Determination -- Mean Distance Calculation -- Statistical Tests -- Conclusions -- Works Cited -- Appendix: Source Code Used For Analysi
Analyzing the effects of persistent hyperglycemia on Gallus gallus and Homo sapiens peripheral neuron apoptotic rate simulating diabetic peripheral neuropathy.
No full textImpact of cortisol treatment on specific cell types in the regenerating caudal fin in zebrafish.
No full text68 leaves; illustrations.Includes bibliographical references (leaves 63-68).Cortisol is a stress hormone that is regulated by the hypothalamic pituitary adrenal axis which is impacted by both circadian rhythms and acute stress. If stress becomes chronic, cortisol levels in the body continually rise instead of having natural oscillations, which can predispose individuals to compromised physical and mental health. Since stress hormone receptors play a role in gene regulatory networks, the effects of chronic stress can be seen through studying gene expression. The effects of chronic stress on zebrafish were investigated by exposing embryos to cortisol and studying the ability of those adults to respond to a stressor later in life (tailfin amputation) using bulk genomics methods (Hartig et al., 2016). However, the main limitation of bulk genomics methods is the loss of single cell resolution. This means that observed differential gene expression patterns could either be due to true differences in gene expression as a response to treatment, or due to the growth patterns of different cell types since each cell expresses a unique transcriptome.
Previous work understanding the cellular diversity of the caudal fin and the impacts of chronic early life stress on the regeneration of the caudal fin come together in the present study to indicate what cell types of the regenerating caudal fin are impacted by chronic early-life stress. The goal of this research is to explore the differential cellular responses in adult zebrafish to chronic early life stress by studying the regenerating tailfin. The results reported here indicate that overall, hematopoietic cells in adult zebrafish are most effected by the chronic exposure to cortisol in early development. In addition, these results demonstrate the usefulness of single cell genomics methods to provide cell type context to previously collected bulk genomic data.Introduction -- I. Stress and cortisol -- II. Chronic Stress -- III. Zebrafish as a model organism -- IV. Hartig et al. (2016): connecting early life stress and regeneration -- V. Limitations to interpretation of Hartig et al. (2016) -- VI. scRNA-seq -- VII. Using scRNA-seq to study cellular diversity of the caudal fin -- VIII. How scRNA-seq data can inform bulk RNA-seq data -- IX. Present Study -- Methods -- I. Sorting bulk differential expression data by cell type -- II. RNA-seq analysis -- III. RNA-Sieve -- Results -- I. Bulk data sorted into cell types by single cell marker genes -- II. Results from RNA-seq analysis -- III. Estimated cell type fractions in bulk samples -- Discussion -- 5 Appendix -- IV. Bulk RNA-seq details -- V. Code for sorting bulk differential expression data by cell type -- VI. Code for RNA Sieve -- Reference
Local and Landscape Level Effects on the Abundance, Morphometrics, and Diet Diversity of Invasive mantids Tenedora Sinensis and Mantis religiosa.
Full text link63 leaves; illustrations.Includes bibliographical references (leaves 44-48).Arthropod Generalist Predators (AGP) play a substantial role in the ecosystem, feeding on a variety of prey items across trophic levels with little to no selective bias. As a result, AGP can be especially problematic if introduced to new environments, disrupting food webs and causing reductions in native populations, which can lead to top-down ecological cascades. In this study, we researched two AGP which are invasive to the Northeastern United States, the European mantis (M. religiosa) and the Chinese mantis (T. sinensis), both of which inhabit early-succession meadows and fields. These environments are noteworthy in that they are fragmentary by nature, and as such, inhabitant species diversity is heavily constrained by patch size, connectivity, and plant diversity. In order to assess how these constraints influenced the abundance, growth, and diet of M. religiosa and T. sinensis, we combined remote sensing, plant diversity surveys, and in- and ex- situ abundance, morphometric, and DNA metabarcoded gut content data to find correlations between these landscape, terrain and individual level variables.Introduction -- Methods -- Study Sites -- Mantis Capture -- Mantid Dissection -- Local Site Variables -- Landscape Level Variables -- Statistical Analyses -- Results -- Abundance Survey -- Morphometric Survey -- Gut Contents Survey -- Local Level Variable (Plant Diversity) Survey -- Landscape Level Variable Survey -- Discussion -- Local and Landscape Level Variables -- Species Level Variables -- Conclusions -- Broader Implications -- Literature Cited -- Figures, Tables and Graph
