Assessing the Impact of Block-Selective Homopolymers on the Diffusion of Payloads Through Polymeric Gels

The goal of this project is to investigate the impact of a gel-miscible polymer additive on gel nanostructure, gel mechanical behavior, and sodium bis(2-ethylhexyl) sulfosuccinate (AOT) release rate. Characterizing gels’ mechanical behavior and release of AOT through these gels will benefit future applications like transdermal drug delivery through informed structure-property (i.e., nanostructure-diffusion) relationships. Previous work in our group has shown that gel nanostructure is tuned by varying the amount of gel-forming SEBS copolymer. The purpose of this project is to further investigate methods of gel nanostructure tuning by identifying the impact of a discrete phase-selective polymer on organogel properties. Specifically, the impact of additive polymer concentration of gel nanostructure, mechanical response, and diffusivity will be studied. The current work uses Fourier-transform infrared spectroscopy (FTIR) to track changes in gel AOT concentration over time for gels with ranging homopolymer concentrations. The acquired data is modeled using Fick’s laws to yield a diffusion coefficient for each gel formulation. We hypothesize that the aforementioned nanostructure trends are the culprit for our observation that diffusion of AOT decreases with increasing polystyrene additive polymer concentration. Understanding these relationships will provide key insight for biomedical and agricultural payload delivery applications.

The Show Must Go On!

The Theatre and Dance Department periodically awards the honor of an Individual Production Project to seniors who have demonstrated advanced work and a deep commitment to an area of theatre production. This project allows students to assume a leadership role for a mainstage production under the supervision of a faculty advisor. Brooke Echnat and Catherine MacKay were awarded Individual Production Projects to serve as the Director and Dramaturg for Bliss (or Emily Post is Dead) by Jami Brandli.
Bliss follows the Ancient Greek characters Medea, Clytemnestra, Antigone, and Cassandra, now pill-popping housewives, in 1960s NJ. Cassandra, a black woman, is gifted with the art of prophecy but cursed by Apollo that no one will believe her visions. She seeks to prove these women can have control over their lives in this modern era. Can we reclaim our “fates” or are our fates predetermined by societal structures set in place?
As Director, Brooke engaged in various mediums and methodologies as she navigated directing in a pandemic. She utilized both virtual and in-person rehearsal processes. Along with the efforts of her cast, crew, and collaborators, she was able to create a piece of theatre at a time when many theaters in our country are still shutdown.
As the Dramaturg, Catherine researched many topics related to the play such as Greek Mythology and Emily Post’s Etiquette to help the production team and actors better understand the world of the play. Catherine’s research provided foundational material that informed the creative decisions of the play.

Housing Illness in a PA Mushroom Town

The relatively small PA town of Kennett Square produces half of the fresh mushrooms for the entire United States. To accomplish this feat, the community relies predominantly on a Latinx immigrant workforce. In order to accommodate this labor source, the local government produced housing in the 1960s. Yet, due to health concerns surrounding abhorrent conditions, the government-provided establishments were discontinued by law in the 1980s. 40 years later, this project investigates how non-government organizational workers in Kennett Square and the surrounding region perceive the current relationship between housing and health outcomes among Latinx community members under coronavirus conditions. The project consists of 21 semi-structured interviews with high and mid-level workers at non-governmental organizations (NGOs) that specialize in issues of immigrant health and housing.
Through transcribing and coding the interviews with the software Atlas.ti, data revealed that my interlocutors believe that the Latinx population in Kennett Square suffers housing-related health outcomes due to low educational levels, relatively low income, and both explicit and structural racist elements. These findings approach a more thorough understanding of housing and health-related issues among the Latinx population in Kennett Square and highlight future areas of scholarship surrounding the region.

To Believe or Not to Believe: A Closer Look at the Impact of Sexual Assault in Politics

Since the viral 2017 #MeToo movement, public opinion on cases of sexual misconduct has been shaped by the mainstream media coverage of high profile stories. A shift in public attitude towards these issues has encouraged more victims to come forward and share their stories, many detailing harrowing events perpetrated by successful businessmen and politicians. Credible accusations continue to come forward, and while some end in legal action, many do not, and perpetrators face little to no consequences. I examined how individuals respond to issues of sexual misconduct and assault in politics, and based on the severity of the accusation, how they respond. Through my survey data research, I was able to isolate responses to see the influence that party affiliation and gender have on individuals opinion formation, as well as how the politicians prior conduct history affects the response. The research reflects an overall partisan difference between Republicans and Democrats in terms of reaction, with Democrats consistently being in favor of harsher consequences, both when Democratic, and Republican perpetrators are involved. Additionally, individuals respond more harshly when the accused politician is of the opposite party. This pattern was consistent across the different severity treatments, as well as the conduct history treatments. Generally, when a history of sexual misconduct was present, individuals of both parties reacted more harshly. In summation, there is significant evidence of partisan bias in the public evaluation of sexual misconduct allegations. I also discuss several prominent cases of sexual misconduct by politicians in order to demonstrate how the public has formed opinions in the wake of scandal.

Location Dependent Mechanical Behavior of Aponeurosis Tissue Under Uniaxial Tensile Stretch

Aponeurosis is a connective tissue that serves as an extension of tendon, attaching to muscle fibers that do not fully extend to the tendon. The material properties of aponeurosis – and thus its mechanical function in the body – are poorly understood. The goal of this work was to perform uniaxial tensile testing to measure the mechanical response of aponeurosis tissue as a function of thickness and location from tendon to muscle. Ten samples measuring ~60mm by 10mm were cut with tissue fibers running lengthwise, and the thickness was measured every 5mm. Uniaxial tensile testing was completed on a custom planar biaxial material testing system with digital image correlation (DIC) to track sample strain. The average nominal (engineering) stress and Lagrange strain values were determined for two regions: the thinner section that connects to muscle fibers and the thicker section that connects to the tendon tissue. Linearized moduli were determined at each time point by dividing nominal stress by Lagrange strain. Paired t-tests (p<0.05) were performed on the Lagrange strain and linearized moduli at each time point. Statistical results indicated that there is no significant difference in the strain of an aponeurosis sample at different thicknesses, but that under greater tensile loads, aponeurosis may exhibit higher moduli corresponding to thinner sections. These results show the material properties of aponeurosis tissue are inhomogeneous and can be used to develop more accurate simulations of muscle-tendon unit mechanical function. Such simulations provide necessary insight into how healthy versus impaired muscle drives the movement of vertebrates.

Fighting Food Waste With Portion Sizes

Problem Statement: The US wastes nearly 40% of our food, creating 125-160 billion pounds of waste annually, leading to high emission rates, resource depletion, and food insecurity. Research Question: What are the most effective waste mitigation and management strategies in the restaurant industry that could be utilized to produce a more sustainable environment? A survey administered on campus to classmates to investigate habits, behaviors, knowledge, and potential solutions around food waste yielded significant differences in how much of a meal was thrown out between fast food restaurants, full service restaurants, and buffets. While 25% of respondents throw out 11% or more of their meal at fast food restaurants, the amount of respondents throwing out 11% or more of their meal swells to 37% at full service restaurants. Asked why they throw this food out the most common responses included: Too large portions, ordering too much, inconsistent appetite, and leftovers brought home being thrown out. We deduce the differences are due to one size fits all plates, which are typically over the recommended calorie count. While a variation of small, medium and large sizes are often offered at fast food restaurants, no such options exist at full service restaurants. Males said the portion size of their meal correlated to their appetite 69% of the time but females said the correlation only occurred 57% of the time. Presented with various food waste mitigation strategies respondents were most in favor of the idea of customized menus with multiple portion options. 92% of respondents said they were at least somewhat likely to purchase a smaller portion for less cost. Meanwhile, 55% of respondents are somewhat likely to order smaller food portions for the identical price of the larger meal. Therefor in order to reduce food waste we propose implementing multiple portion options at restaurants.

Effect of White Matter Stimulation on Clinical Outcomes in Thalamic Deep Brain Stimulation for Essential Tremor

Deep brain stimulation (DBS) is a surgical procedure where electrodes are implanted in the brain before stimulating the tissue with electricity. DBS of the ventral intermediate (VIM) nucleus of the thalamus and the subthalamic nucleus (STN) are established treatments for the motor symptoms of essential tremor (ET) and Parkinson disease (PD), respectively. Motor outcomes, such as tremor, rigidity, and bradykinesia, after VIM and STN DBS can vary considerably across patients and strongly depend on the location of stimulation relative to the surgical target. Previous research suggests that stimulation of the white matter (WM) tracts lateral to the VIM, the gray matter (GM) target, results in better DBS outcomes. The objective of this retrospective study is to determine how the spread of stimulation to WM during VIM DBS relates to therapeutic and non-therapeutic outcomes in ET patients. For the first phase of this research, a MATLAB algorithm that can differentiate brain tissues, such as WM, GM, and cerebrospinal fluid, from medical imaging based on tissue anisotropy was developed. Patient-specific tissue anisotropy was derived from diffusion tensor imaging data acquired for individual patients who received DBS (n = 22). To evaluate the performance of the algorithm, it has been trained and tested across both ET and PD patient data sets. This algorithm can be used to differentiate brain tissues in any region of interest. The modeling framework utilized in this study could be used to identify optimal stimulation sites on an individual basis, thereby improving clinical outcomes.

BRAKHAGE’S ADJACENTS

The goal of BRAKHAGE’S ADJACENTS is to better understand the working methods and aesthetic decision making of the avant-garde filmmaker Stan Brakhage (1933-2003). By focusing upon his use of montage (the complex way in which he combined shots in his non-narrative––and almost entirely silent––16mm films), we learn more about Brakhage’s editing habits as well as the messaging behind his very challenging films. This is done by viewing splice-adjacent frames on an actual film strip, showing the literal cuts that were made when the films were produced. BRAKHAGE’S ADJACENTS draws from wider histories of narrative filmic editing [notably the advanced montage ideas of Sergei Eisenstein (1898-19480] while adapting these notions to the under-realized realm of avant-garde. 

Little Arnot Run: An Evaluation of Groundwater-Surface Water Interactions with Regard to Hyporheic Exchange and Temperature
Little Arnot Run is a second-order stream in the Allegheny National Forest, Pennsylvania. In many areas the stream was dredged, straightened, and converted to a narrow, deep, single-thread channel, which continues to be disconnected from the floodplain. This project is part of a larger stream restoration study by the United States Forest Service (USFS) and Bucknell University currently underway working to characterize the factors controlling geomorphic processes operating within the watershed in order to direct restoration activities set to take place later in the year. Preliminary analysis of groundwater piezometers, stream temperature gage station data, and weather station data suggests significant hyporheic exchange to the channel. The current assessment of both shallow and alluvial aquifers as well as in deeper sections of the stream is being done in order to quantify groundwater-surface water exchange and potential for reconnecting abandoned side channels and vernal pools on the floodplain.

Mechanics of Wax-based Gels with varying Polymer Concentration: An Overview

Wax-based polymer gels have the potential to vastly improve the shelf life of transdermal drug patches. It can be reasoned, and addressed with future testing, that diffusivity of wax-based gels in the solid wax phase is relatively negligible and only becomes significant once the material transitions to the gel phase. The gel phase of this type of material is comparable to amorphous mineral oil-based gels. If the melting point of the wax-based gels is constrained between human body temperature and room temperature, diffusion of the payload in gels can be controlled to only occur when the patch is in contact with the human skin. Our first step in studying wax-based polymer gels is their mechanical behavior. Testing of both the solid wax and gel phases of the wax-based gels will provide foundational physical properties of the gels and aid in moving them towards application in the medical industry.