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ENGINEERING ARYLBORONATE – MODIFIED DEXTRAN POLYMERS FOR USE AS BIOCOMPATIBLE, BIODEGRADABLE MATERIALS IN MICROPARTICULATE IMMUNOTHERAPY
No full textMicroparticulate immunotherapy holds promise to vaccinate against difficult targets like cancer. Many vehicles exist, but triggering is often based on pH or passive hydrolysis. The most effective cells at promoting an immune response are dendritic cells. The lysosomes of these cells are highly oxidizing relative to acidifying, so an oxidation-sensitive vehicle could be a significant advancement in this field. One promising class of materials being developed toward this end are aryl boronate- modified dextran polymers. Boronic esters for oxidation-sensitive delivery vehicles are typically made using pinacol (Pin) as a diol. However, Pin- based aryl boronate-modified polymers are prone to interchain transesterification that restricts their solubility and ability to be tuned and synthesized. This phenomenon also inhibits the polymers ability to be processed into discrete particles. To solve this, the diol used in the modified polymer was varied in order to develop a pattern for how the structural properties of different diols affect the behavior of the molecule as a whole. In addition to pinacol, (-)-pinanediol, norbornenediol, and cis- 1,2-cyclopentanediol were tested using 1H-NMR to track the formation and disappearance of key elements of interactions between their ester forms and dextran. The stability of these diols in other contexts have been assessed, but those conclusions have not yet been applied to the addition of those diols as boronic esters onto polymer backbones. It was confirmed that in accordance with patterns developed in literature, pinanediol formed the most stable boronic ester of the four analyzed and retained its stability when incorporated into a dextran polymer. This behavior is due to pinanediol’s cyclic nature, rigidity, and high degree of steric hindrance.
Subsequently, the synthesis of a new aryl-boronate modified dextran polymer was achieved using pinanediol (PD) to replace Pin (PDB- Dex). This modified dextran improves upon Pin-based materials by maintaining its solubility in organic solvents and resulting in smooth, discrete, microparticles that are consistent in size. Microparticles were prepared and analyzed using SEM and DLS methods. Degradation of particles was triggered with hydrogen peroxide and tracked using 1H-NMR to confirm the mechanism of degradation. A standard BCA Assay was adapted to measure the rate of degradation under physiologically relevant conditions, and it was found that PDB-Dex is sensitive to peroxide levels as low as 0.01 mM. Preliminary biological assays and in vitro studies show low cytotoxicity and the ability to deliver an immunostimulatory agent.Biochemistr
Convergent Evolution Between the Mouthparts of Eurypterus lacustris and Procambarus clarkii
No full textEurypterus lacustris has been reconstructed as a mid-sized detrivore and carnivore that was preserved in hypersaline shallow water environments (Nudds, 2008). Today, Red Swamp Crayfish (Procambarus clarkii) are about the same size, eat similar materials, and also live in highly variable shallow water environments (Correia, 2003). They also exhibit similar proportions in their leg segments, and have several masticating and manipulating mouthparts to aid in food processing.
I argue that this similarity in trait space may indicate convergent evolution between two distantly related groups. Gnathobasids are an ancestral trait to arthropods since the Cambrian (Bicknell, 2018), however the arrangement of longer walking legs and short feeding legs (chelicerae and maxillae) seems to have evolved in both Eurypterus and Procambarus. I interpret this as a convergent adaptation to eating detritus and small bottom-dwelling animals in an aquatic environment.
However, our analysis shows that Eurypterus and Procambarus mouthparts are morphologically dissimilar, and therefore do not indicate convergent evolution has occurred. I propose that size is a large driver of mouthpart selection, and discuss new techniques such as 3D reconstruction to assess convergent evolution.Biological Science
Imperfect Internships: It’s Not the End!
No full textThis summer started out a little bumpy, as I struggled with an internship and organization that I was excited about but was not learning enough in. The chasm between my vision for the summer and the reality was growing wider when I stumbled upon an opportunity at the Indian Council for Research on International Economic Relations (ICRIER) in New Delhi. I went on to work with a team that was researching the existing scenario of solid waste management in India under a broader theme of ‘Challenges and Opportunities of Urbanization’. I performed quantitative and qualitative data analysis and drew comparisons between some major cities of India. I contributed to determining practical ways to upgrade the system and gained insight on various issues faced by a developing economy. My presentation will expand on how my two internships taught me to navigate tricky situations, take initiative, and explore without hesitation.Everyone dreams of finding the perfect internship, but what happens if you don’t? Internships can bring challenges at every stage, and this panel wants to help you be prepared for these potential pitfalls. This summer, these five panelists worked in internships across a wide variety of fields, including think tanks, arts non-profit organizations, NGO’s, academia, and Wall Street. Come hear about some of the hurdles that can arise throughout summer internships -- and how to overcome them. Topics will include navigating difficult work environments, taking initiative, and making the most of your internship to create a solid springboard for the future
Teaching for a Difference
No full textWhen I decided I wanted to major in economics, I felt relieved. I would live a normal life and have a normal job. The path of studying economics felt stable to me. Normal would be far from anything I was ever accustomed to, but it would be a change I could come to accept. My interest in economics led me to interning at the Daraja Academy, located in the center of Kenya. I worked as a business administrative intern at a residential high school for girls. Developing an online point of sale, researching potential partner organizations, and creating data entries were all useful real-life tools and tasks I would need in order to be successful in the field of economics. Although economics led me to the Daraja Academy, the Daraja Academy led me to a place where I realized I want to do more. I want to have more and create more than just a professional life as a normal economist. In my presentation, I will speak about my experience in Kenya, how working in this field helped me discover exactly what I want to do, and led me to a path far away from economics.Education is found inside and outside of the classroom, which is something the four members of this panel, Ariel, Sabrina, Rachel, and Kathryn, will discuss as part of their reflection on their summer experience. Our experiences stretch from basketball courts in Vietnam to riding arenas in Reno, management in Kenya, and teaching in Argentina. Viewers will take away from our panel a broader understanding of different cultures, self-reflection, community involvement and how one internship experience can shape future career aspirations. Reflecting on their internships this summer, these panelists gained insight into how the work they did helped to shape how they wish to proceed in their future career aspirations
Exploration of Material Transformation
No full textFurniture design is the underlying notion in all of my artworks. Some works are directly
derived from recognizable features of furniture, while others, though heavily influenced
by furniture design, may not be so obvious to the viewer in the first glance. I identify this
set of work as furniture pets, because they are in fact carnal and animalistic in their own
way, giving each piece its own life and personality. They do not necessarily mimic nature,
rather mimic the ways of nature through their organic magnitude, the rate of growth,
form and structure. These physical objects function optically and sculpturally,
experimental in both material and process. Each piece had its share of visual moments
where material and process were tested and challenged, thus, setting the process behind
making a piece somewhere between intuition and strategy. These ideas account for my
intuitive ways of working to produce a sculpture while navigating through omnifarious
ideas and experiments. Regular/irregular repetition of patterns and reoccurring shapes
are the key aspects of my work, which not only reason my aesthetic value but also makes
sense of the logic behind the formation of a piece. Although my overall process is
intuitive and improvisational, there are certain decisions that come after one another,
therefore, making the process crucial to the making of the sculptures. The objects reveal
just enough of themselves to arouse curiosity, leaving the viewer to pursue their identity,
situation, and purpose.Art Studi
Late Pleistocene and Holocene climate change on the Kenai Peninsula, Alaska: Interpretation of a marl record from Kelly Lake
No full textKelly Lake, located in the lowland of the Kenai Peninsula, Alaska, is a non-glacial, organic-rich, subaqueous spring-fed lake. A sediment core (KLY18-4) recovered from 4 m water depth offers multiple proxies including d18Omarl and d13Cmarl values from ~14.1 to ~6.9 cal kyr BP, calcium carbonate content, magnetic susceptibility, and stratigraphic analysis to reconstruct lake level fluctuations, shifts in effective moisture, and precipitation source to the Kenai lowland from ~14.7 cal kyr BP to present.
The shallow-water macroalgae, Chara was likely the primary precipitating agent of calcium carbonate, or marl, at the core site from ~14.1 to ~6.9 cal kyr BP when lake level rose and the zone of marl production shifted to shallower water. Calcium carbonate content is used as a proxy for Chara growth and ambient water conditions as Chara prefers clear, shallow water.
Kelly Lake experienced overall lower lake levels and was likely a closed basin between the time of lake formation (~14.7 cal kyr BP) and ~6.9 cal kyr BP. Multiple shifts in lake level with periods of basin desiccation at the core site are also apparent during this time. The Younger Dryas exhibits cool and dry conditions at its onset but increasingly warm and evaporative conditions for its duration. The latter part of the Early Holocene shows an oscillatory pattern of lake level rise and fall and stepwise lake level rise beginning at ~7.5 cal kyr BP. Around 6.9 cal kyr BP the lake assumed relatively modern conditions with minimal subsequent fluctuation. Additionally, tephra deposits become more frequent here. Six deposits are found in the stratigraphy between ~6.9 cal kyr BP and present, and only one deposit is found between ~14.7 cal kyr BP and ~6.9 cal kyr BP. This suggests a potential shift to moisture sourced dominantly from the southwest bringing greater rates of precipitation and more ash fall from the Aleutian arc to the Kenai lowland.Geolog
Mother Tongue: Sixteenth-Century Sephardi Women's Contributions to Judeo-Spanish
No full textUpon their expulsion from the Iberian Peninsula, which began in 1391 and culminated in the issuing of the Alhambra Decree in 1492, the Sephardim who migrated to the Ottoman Empire continued and adjusted their cultural and religious traditions in the diaspora. A central element of the Sephardi culture's survival was the continued use of Judeo-Spanish, which descended from dialects of Ibero-Romance to become the heritage language of the Sephardi people in the diaspora. This thesis explores women's usage of Judeo-Spanish in the sixteenth century -- the first full century after the 1492 expulsion -- and their contributions to the language's preservation. The text of Rabbi Meir Benveniste's Seder Nashim (1565), as well as the thematic and lyrical content of various Ottoman Sephardi romance and kantiga ballad traditions, suggest that Sephardi women, who used Judeo-Spanish as their primary form of communication during the sixteenth century, influenced the language's cultural significance and the preservation of certain lexical and grammatical features.Other or Special Majo
Shutesbury Aquifer Resiliency in the Face of Climate Change
No full textThe climate is rapidly changing due to human activity, and these changes will impact our water resources. In the town of Shutesbury, Massachusetts, a municipal water supply does not exist. Instead, water comes from private wells that tap into a vast and complex bedrock groundwater system. Prior to this study, little information existed regarding the seasonal fluctuations, the sensitivity of the aquifer to short or prolonged drought, or the ability of the aquifer system to support future development in Shutesbury. Still less was known regarding how the aquifer system could potentially be impacted by climate change. Reports of lowering water levels in New Hampshire and the neighboring town of Pelham were a cause for concern. In 2014, eight monitoring wells were drilled at four locations in order to monitor seasonal changes in water level and to establish a baseline for future levels. Water levels were found to fluctuate seasonally, and despite a snow-heavy winter and summer drought, spring static water levels returned to similar levels each year. Based on the small amplitude of seasonal fluctuations, the lack of a lasting impact of the drought of 2016, and expected future increases in rainfall, it appears that the shared aquifer should continue to serve as a viable source for the town.Geolog
Who is Alice? An Analysis of the Character of Alice From the Origins of Her Representation to Surrealist Interpretations
No full textThis thesis analyses the character of Alice in Lewis Carroll’s, Alice’s Adventures in Wonderland through different visual representations of Alice. I discuss John Tenniel’s world famous illustrations, which accompanied the text’s original publication, and were born from Tenniel’s career as a popular cartoonist. I also look at representations of Alice drawn by Carroll himself, sketches which exude a pre-Raphaelite influence. I then discuss two surrealist interpretations of Alice, illustrations done by Salvador Dali in 1969, and a film adaptation, Alice by Jan Svankmajer, done in 1988. Dali used one of his classic motifs, steeped in significance, to represent Alice and Svankmajer twists Wonderland into something more sinister. Each version of Alice includes the unique perspective of her creator. When the origins and inspirations for these representations are compared it is apparent that Tenniel’s world famous original illustrations do not represent Alice honestly, and that the visual representations done by Dali and Svankmajer hold more relevance to the written character of Alice. Commonly, what is original is thought of as truer or more important than adapted versions. This comparison between versions of Alice demonstrates that interpretation is not a less valid form of representation and that it can in fact enhance a work.Englis
Environmental Governance in Motion: Practices of Assemblage and the Political Performativity of Economistic Conservation
No full textThis article critically explores the dynamic, constitutive processes that animate economistic conservation
and sustainable development as an expression of governance-beyond-the-state. I focus attention on governance
in motion—expanding logics, hybrid practices, diffuse networks, and shifting social technologies
that incrementally reshape power dynamics and the institutional domains that enable and constrain
them. While the majority of institutional approaches to environmental governance emphasize intentional
designs rooted in collective choices, less attention has been focused on dynamic processes of
assemblage resulting from differentially coordinated actions across interrelated networks. Building from
Foucauldian perspectives on governmentality and biopower, I argue that processes of assemblage help to
constitute new techniques of governance aligned with the language and practices of economics. I examine
two business and biodiversity initiatives—the Natural Capital Finance Alliance and the Business and
Biodiversity Offsets Programme—in terms of five practices of assemblage: authorizing knowledge, forging
alignments, rendering technical, reassembling, and anti-politics. I highlight four dimensions of political
performativity associated with business and biodiversity initiatives that exemplify environmental governance
in motion: discursive amplification, organizational articulation, institutional re-shaping, and technical
instrumentation. Governance in motion reflects the distributed power dynamics of diverse
individuals and collectives in generating economistic techniques of governance