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Imagination, Sensation, And Habits: Medical Rhetoric And Popular Literature In Perceptions Of The Paris Opera: Response To “Dr. Louis Véron, Medical Philosophy, And Medical Practice At The Paris Opera” By Elizabeth Claire
No full textIschemia/Reperfusion Injury Enhances Accumulation Of Perfluoropropane Droplets
No full textObjective: Perfluoropropane droplets (PD) are nanometer-sized particles that can be formulated from commercially available contrast agents. The preferential retention of PDs in diseased microvascular beds can be detected by ultrasound imaging techniques after acoustic activation and offers an opportunity for the detection of such processes as scar formation or inflammation. We hypothesized that in the presence of ischemia/reperfusion (I/R) injury, retention of intravenously injected PDs would be enhanced. Methods: Using an established intravital microscopy model of rat cremaster microcirculation, we determined the retention and subsequent acoustic activation behavior of PDs in exteriorized rat cremaster tissue. DiI-labeled droplets (200 µL) were administered intravenously. Acoustic activation was achieved with a clinical ultrasound system at two ultrasound frequencies (1.5 and 7 MHz). Results: Fluorescent microbubbles could be detected in the microvasculature after intravenous injection of PDs and subsequent acoustic activation. Increased retention of PDs was observed in the I/R group compared with control group with both ultrasound frequencies (p \u3c 0.05). Using higher-resolution microscopy, we found evidence that some droplets extravasate to the outside of the endothelial border or are potentially engulfed by leukocytes. Conclusion: Our data indicate that targeted imaging of the developing scar zones might be possible with ultrasound activation of intravenously injected PDs, and a method of targeting therapies to these same regions could be developed
In The Kingdom Of The Thunder Dragon: Happiness, History, And Environment In A Changing Bhutan
No full textLandlocked, mountainous, and surrounded by global giants India and China, Bhutan has provided remarkable leadership on both climate action and human happiness, despite its pre-2023 status as a least-developed nation. Bhutan was the first country to be internationally recognized as carbon neutral; it is also the birthplace of “Gross National Happiness” (GNH), a pointed alternative to Gross Domestic Product (GDP) as a means of measuring the success of national policies in promoting citizens’ wellbeing. Yet Bhutan has also been a site of ethnic conflict, with roughly tens of thousands people displaced into refugee camps in the 1990s and eventually resettled abroad.
International views on Bhutan tend to be sharply split between admiration for its democratizing development strategies and opposition to its human rights abuses—a division partly maintained by Bhutan’s tight limits on immigration and foreign travel within the country. In the first book-length study of its kind, In the Kingdom of the Thunder Dragon explores the tensions and contradictions of Bhutan’s rapid political and economic transformation from the perspective of a Fulbright scholar helping start a new master’s program in the remote east of the country.
Mingling personal narrative with historical context to engage undergraduate students and general readers, In the Kingdom of the Thunder Dragon explores Bhutan’s Vajrayana Buddhist heritage and ongoing embrace of tradition alongside development, the country’s newly minted democracy amidst a complicated history of citizenship and belonging, and the challenges the nation faces in a period of increasing globalization. Betsy Bolton further explores Bhutan’s recent events surrounding the 1990s expulsion of the Lhotshampa people and the development of GNH in the early 2000s. From here, Bolton illuminates how these historical narratives and issues have impacted Bhutanese citizens and students through stories gathered at educational and artistic institutions, festivals and community events. In the Kingdom of the Thunder Dragon is a fresh, accessible approach to Bhutanese history and will interest general readers as well as scholars of Asia, history, economics, sociology, and environmental studies
Photovoltaic-Electrolysis Device Optimization
No full textWith the exponential rise in fossil fuel consumption, an efficient clean alternative energy source is needed. A promising solution is utilizing solar-driven electrolysis to produce clean hydrogen as a viable clean energy source. Electrolysis currently accounts for 4% of hydrogen production, and this report details the development and optimization of a small-scale solar driven device for PEM electrolysis as an alternative to fossil fuels. This report focused on analysis for the optimization of electrocatalysts, and the integration of a PV-PEM-Battery system. Evaluation of three different membranes performance determined an anode loading of 2 mg/cm2 of IrRuOx to be the best performing and most efficient (ηmax=92.5%, ηvoltage=79.14%). PV-PEM-Battery system analysis verified the successful indirect coupling of components using MPPT tracking and a step-down DC-DC converter. Analysis also verified the reliability of the system to provide consistent power to the electrolyzer despite intermittent periods of irradiance, and regardless of the battery charge state. Suggested operating conditions were determined to be in a range from 1.7-1.85V, and quantification of hydrogen output within the acceptable operating range was conducted. It was determined that the output rate for the system at 1.85V, 4A and at 25oC was 34.43 mL/min. A system design was carried out for a scaled-up system based on experimental data and theoretical extrapolation yielding a feasible, yet conservative design consisting of a 286 cell stack, with 109 PV panels, operating at 1.8V and 25oC. For future work, I would focus on full system development and analysis
The Amalgamation: A Complete Open-Source Pair of Smart Glasses
No full textThere are many open-source smart glasses projects across the internet, all with interesting features and individual sets of hardware and software. While impressive, these projects are generally single-purpose; they focus on one feature and the rest of the product is mediocre in quality. We have produced a design and (nonfunctional) prototype for a new design combining several of these individual concepts: The Amalgamation. Our product includes a high-resolution OLED microdisplay, a high-quality, hobbyist-reproducible frame, a custom PCB for hardware addition and power regulation, an IMU for data and control, and a custom plugin-based software suite with a simple interface and industry-standard libraries. While our display fails to initialize, our work presents a foundation upon which to build a version that does function
Closing the Loop: Solar-Powered Vermicomposter
No full textOrganic waste is oftentimes poorly managed and directed to landfill and incineration, as more sustainable alternatives such as traditional composting are not always accessible. Swarthmore College has a robust composting partnership offsite, however, it does not leverage avenues for waste stream circularity on campus to its full potential. Vermicomposting, composting that incorporates earthworms (Eisenia fetida), consists of a method to achieve small-scale and accessible composting. The goal of this project was to create an on-campus, low-maintenance, replicable, and sustainable vermicomposter to efficiently repurpose food waste from Swarthmore’s dining hall into nutrient-rich soil amendments for the adjacent Our Food Garden. The vermicomposter’s design allowed leachate (i.e., compost tea) to drain through a perforated panel and be collected in a compartment below the soil layer, accessible through a tap. A monitoring system, run by a solar-powered Arduino Nano Every, tracked changes in compost weight, oxygen levels and soil conditions of temperature, moisture, and pH. Sensors were appropriately calibrated and data were stored in an SD card. The monitoring system accurately recorded weather-induced changes within the vermicomposter, mainly temperature and humidity fluctuations, and less accurately tracked other parameters. Total additions of food scraps to the vermicomposter were 85 lb, generating a harvested compost batch of 80.5 lb with an increase in organic matter of 9.14%, when compared to the original soil. Leachate production was minimal and structural challenges arose given fabrication with untreated wood. Overall, this project demonstrated a viable vermicomposter and monitoring system that yielded sufficient compost, created opportunities for research and replication, and contributed to waste stream circularity on campus
Characterizing Potential Models of the MEK and ERK Kinase Interaction
No full textThe mitogen activated protein kinase (MAPK) signaling pathway is involved in a variety of cellular processes ranging from proliferation to differentiation to apoptosis. Dysfunction of the pathway is implicated in a range of human cancers which makes regulation of the pathway an attractive therapeutic target. Mutations often occur in proteins upstream in the pathway which serve as common targets for drug therapies; however, such approaches are limited by drug resistance. MEK and ERK kinase are downstream effectors of the pathway and have a highly specific interaction that could serve as an alternative target for pathway regulation. Allosteric methods of inhibition can lend greater drug specificity compared to conventional therapies. Yet, the exact details of the MEK-ERK interaction remain unclear as no high-resolution structure of the MEKERK complex exists.
We aimed to characterize potential models of MEK-ERK interaction by identifying residues involved in binding using experimental and computational methods. We generated complexes of MEK and ERK using computational docking and AlphaFold3 to identify residues implicated in binding and used sequence alignments to identify conserved residues likely implicated in binding. We mutated residues of interest and characterized changes in binding affinity using biolayer interferometry. We identified MEK residues L235, E312, L314, and K362E as potentially involved in binding. We also determine ERK-L234 is implicated in a hydrophobic pocket with MEK-L235 and L314.
Future work can utilize this information to stabilize the MEK-ERK complex through mutagenesis for use in structural studies that might elucidate a complete experimental structure of the complex
\u3cem\u3eMisogyny in Medicine’s Margins:\u3c/em\u3e Patients’ and Physicians’ Conflicts, Challenges, and Camaraderie in Endometriosis Care
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Low Cost NDVI Aerial Imager for Plant Health Monitoring
No full textDue to the spread of Beech Leaf Disease, Swarthmore College and the Scott Arboretum expect to lose all of the beech trees on campus in the next five years. Methods of monitoring plant health are required to act as early warnings for tree loss so that the Arboretum can manage deadfall, erosion, and other adverse effects. Normalized Difference Vegetation Index (NDVI) is a multispectral imaging technique that can assess plant health. NDVI is a common satellite remote sensing technique that has shown promise in drone remote sensing applications. With recent decreases in the costs of optical components, we determined that a low-cost NDVI imager could be mounted to a small drone. This imager would then observe changes in plant health in the Crum Woods over time. Our project involved the design and construction of such a payload. We integrated the payload with a drone development platform, and validated it by flying test flights on Swarthmore’s campus. We identified areas in which our design could be improved, and speculated on what future work is required to mature the payload to meet the requirements of the Scott Arboretum