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Lifelong Civic Engagement
No full textCivic engagement can be broadly defined as the practice of service (volunteering or informal helping), advocacy, and political participation (voting). Older adults are a large and growing population that frequently engages in these civic activities.
In 2022, the Bureau of Labor Statistics reported that approximately one quarter of the 11 million daily volunteers in the U.S. were age 65 and older. Between 2018 and 2021, there was a 10% increase in volunteer hours filled by individuals over age 65. Research shows this trend will be mutually beneficial, improving the quality of life for older adults who are, in turn, positively impacting their communities. This group also consistently demonstrates the highest rates of political involvement in the nation. In the 2024 presidential election, 74.7% of citizens aged 65 and older reported voting, leading all other age demographics
Rational Gridlock
No full textWe examine the design of lawmaking institutions when advocates have agenda setting power and there is randomness in the status quo laws eligible for reform. The institutional designer maximizes voter welfare. We find that the optimal arrangement consists of two lawmaking institutions that must agree to enact any reforms. The institutions do not share preferences with one another or with the median voter. As a result, gridlock arises: the institutions reject some reforms that the median voter favors. However, when reform succeeds, it tends to be modest in scope and to more closely track what the median voter prefers. The optimal institutional design trades off the cost of failing to change law due to gridlock against the benefit of forcing advocates to moderate their proposals and offer more centrist reforms. Surprisingly, voters are best served by a pair of polarized and unrepresentative institutions
The Curiously Minor Role of Minor v. Happersett (Foreword)
No full textThis Foreword introduces a symposium marking the 150th anniversary of Minor v. Happersett, a Supreme Court decision unanimously holding that the Fourteenth Amendment\u27s Privileges or Immunities Clause did not enfranchise women. Notwithstanding its impact on the women\u27s suffrage movement and the subsequent ratification of the Nineteenth Amendment, Minor presents a puzzle: it is a relatively obscure precedent that remains deeply relevant to contemporary legal debates. To elucidate this point, this Foreword juxtaposes Minor with two notorious Supreme Court decisions: Dred Scott and Dobbs.
Like Dred Scott, Minor pairs a morally repugnant result with legalistic reasoning. But whereas Dred Scott is the quintessential anti-canon case, Minor is a footnote in legal education. On the flip side, Dred Scott was overturned by the Fourteenth Amendment, but Minor remains good law. The Nineteenth Amendment merely adopted an anti-discrimination workaround to Minor\u27s holding that suffrage is a not a privilege or immunity of citizenship.
More recently, the Court\u27s decision in Dobbs demonstrates Minor\u27s continuing resonance. Indeed, Dobbs and its aftermath exemplify that the issues contested in Minor in 1875 remain hotly debated today: the rights of citizenship, the role of women in society, and the meaning of the Privileges or Immunities Clause.
Finally, this Foreword briefly summarizes the interdisciplinary papers presented at the conference, covering diverse topics such as election law, feminist studies, legal history, and substantive due process
Extending WUADS Analysis Capabilities to General Aviation Aircrafts with Piston Propeller and Turbo Propeller Engines and Hydrogen Fuel
No full textThe Washington University Aerospace Design Software (WUADS) is a Python-based conceptual aircraft design software for the analysis of subsonic commercial aircrafts. This paper presents modifications to WUADS enabling the design and analysis for general aviation (GA) aircrafts. The updates include revised weight estimation methods as well as a modified method for estimating the performance of piston propeller and turbo-prop engines. For the weight estimation, the average of the GA versions of the Raymer, and NASA FLOPS methods were implemented for each component. Weight analysis accuracy was measured by comparing the gross takeoff weight calculated by WUADS to published data. Engine performance was measured based on two metrics: thrust specific fuel consumption (TSFC), and maximum thrust. TSFC was calculated using the aircraft’s speed, engine efficiency, engine horsepower and fuel consumption rate. To evaluate the engine output calculations, the estimated aircraft range was compared to published design ranges. The Cessna 172 Skyhawk, Piper PA-28-161 Warrior II, and the Beechcraft Bonanza G36 were modeled using WUADS and used to validate this modified framework for GA piston powered aircrafts. The calculated weight for the Cessna aircraft was within 0.4% of the published weight, and the range was within 1.9% of the design range. The Piper Warrior weight was within 1.3% of its published weight, and its range was within 3.6%. The calculated weight for the Beechcraft was within 0.7% of its published value, and the range was within 5.6%. The Cessna-208 Grand Caravan and Pilatus PC-12 were used to validate the turb-prop methods. The calculated weight for the Cessna-208 was within 1.9% of the published weight, and the range was within 0.7% of the design range. The Pilatus weight was within 0.5% of its published weight, and its range was within 7.9%. Given growing concerns over carbon emissions, with aviation accounting for roughly 2–3% of the global carbon footprint, a method was designed for modeling the Cessna-208 aircraft using zero-emission hydrogen fuel alongside traditional kerosene-based fuel to assess feasibility and range [2]. Preliminary results for the hydrogen configurations are being improved upon
MEMS 4110: TRASH-E (Terrain-adaptive Remote Autonomous Sanitation Hauling Engineer)
No full textThe TRASH-E (Terrain-Adaptive Remote Autonomous Sanitation Hauling Engineer) project was created to compete in the 2025 ASME Student Design Challenge. For 2025, the ASME SDC asked for the development of a remotecontrolled robot that could collect and deposit trash from receptacles placed around a miniature city. The robot had to adhere to specific size and weight constraints, as well as obey traffic laws in the same manner as a real driver operating a motor vehicle
MEMS 4110: Interactive Racecar Dynamics Exhibit
No full textVisitors at science museums often struggle to understand how launch speed, lane choice, and banked-curve dynamics influence a car’s trajectory. Existing educational exhibits rarely provide repeatable measurements or clear physics demonstrations. This project addresses that gap by creating an interactive racecar dynamics exhibit with a controlled launcher, 3D-printed banked track geometry, and optical timing gates. The goal is to give users measurable feedback on velocity, lane behavior, and motion through a 31° banked turn while maintaining safety, durability, and fast reset time for continuous hands-on learning
MEMS 4110: Waste Collection Challenge (ASME)
No full textFor our senior design project, our team developed a remotely controlled waste-collection vehicle capable of driving, collecting, and dumping garbage in a small-scale model course. The challenge required the vehicle to navigate streets, obey traffic rules, and collect garbage from designated locations before returning it to a dumpsite without spilling. The system had to meet the ASME Student Design Challenge rules, along with additional specifications provided by our customer, Dr. Potter, including time limits, collection efficiency, and successful, repeatable dumping performance
Improving Neurotechnologies for Chronic Pain through Brain-Computer Interfaces and Invasive Models of Human Cingulate Cortex Networks.
No full textChronic pain is a debilitating and intractable disease characterized by pathological changes to the nervous system. Specifically, chronic pain is associated with changes in neural circuitry, including maladaptive neuroplasticity, cortical reorganization, and changes to descending pain modulation pathways. Neurotechnologies, or technologies that interface with the nervous system, provide a therapeutic modality that can directly target the neuropathology underlying chronic pain. For example, brain-computer interfaces (BCIs) provide a promising avenue for therapeutic neural remodeling, specifically by leveraging neurofeedback to reinforce beneficial neural patterns. However, due to the variability of the functional and structural changes in the nervous system that contribute to chronic pain, BCIs have yet to be optimized to treat chronic pain. Further, our incomplete understanding of the cortical networks that underlie pain perception limits the design and translation of effective BCI systems. This dissertation addresses these challenges through three studies. The first study introduces a novel theta-controlled BCI system, which was tested in six chronic pain patients during an open-label pilot study. Through haptic and visual neurofeedback, the BCI was able to reinforce frontal theta in this study population over a six-week intervention. Patients increased their BCI performance, reflecting thought-driven control of neurofeedback, and showed a significant decrease in pain severity and pain interference scores without any adverse events. Pain relief significantly correlated with frontal theta modulation. These findings highlight the potential of BCI-mediated cortico-sensory coupling of frontal theta with vibrotactile stimulation for alleviating chronic pain. While frontal theta has been identified as an attractive pain-relief biomarker, the neurophysiology underlying this phenomenon is poorly understood, especially in the context of pain. We hypothesized that the source of these frontal theta features was the anterior cingulate cortex. To this end, our second study provides deeper insights into the contributions of activity from the human cingulate cortex (CC) and its networks to surface EEG features. Through invasive electrical stimulation of the subregions of the cingulate cortex and concurrent recording on surface EEG, we characterized the recruitment of CC networks through electrophysiological features captured on the scalp surface. We found that stimulation of the Midcingulate cortex produced distinct surface features in frontal regions, coinciding with our spatial targets during our first study. Further, we were able to characterize the temporal features of each CC subregion on scalp EEG. The final study provides a comprehensive profile of CC effective connectivity networks. The subregions of the CC are highly implicated in the perception of pain, yet precise relationships within its effective networks remain understudied. We mapped divergent effective networks of the anterior, mid, and posterior cingulate in 15 resection-free patients using single-pulse electrical stimulation, quantifying both cortico-cortical evoked potential (CCEP) magnitude and a morphology-based coherence metric, and profiling spatial, temporal, spectral, and inter-regional waveform features with machine learning. Coherence complemented magnitude, revealing hippocampal connections undetected by magnitude, and CC hub regions with equivalent connectivity to the anterior, midcingulate, and posterior subregions. Profiling the spatial distribution of effective networks confirmed that spatial patterns of effective connectivity coincide with distributions of CC white matter tractography. Inter-regional hierarchical clustering showed the midcingulate network had the most stereotyped CCEP morphology across regions. A Random Forest model trained to classify CC effective networks using features extracted from CCEPs reached 75% accuracy and revealed that assumption-based waveform features had the lowest predictive strength. These results provide a detailed, network-level account of human CC effective connectivity and highlight the utility of multimodal, feature-driven approaches over traditional assumption-based metrics. Together, these three studies present a novel BCI modality for treating chronic pain and elucidate neurophysiological mechanisms of pain perception networks critical for the improvement of future neurotechnologies
Applications of Flexible and Bioresorbable Materials for Peripheral Nerve Regeneration
No full textMicroelectronics made of flexible and bioresorbable materials are gaining interest in a variety of areas of clinical medicine. The flexibility of such electronic devices makes it possible to have less mechanical mismatch with biological tissues, ensuring both high efficacy of implanted devices and improved mitigation of foreign body reaction in vivo. The in vivo resorption through hydrolysis allows bioresorbable microelectronic devices to be excreted from the body without the necessity of secondary removal surgeries. The peripheral nervous system plays inimitable roles in daily activity. Research, diagnosis and treatments still need development because of the complexity and fragility of nervous system. Here, we aim to examine the use of flexible and bioresorbable implantable microelectronic devices as a unique vehicle for facilitating regeneration of the peripheral nervous system. The first aim of this work develops adaptive bioresorbable materials and wireless microelectronics as a functional therapeutic electrical stimulator. Polymers are designed to ensure protection during the working timeframe and degrade thereafter. Self-curling electrodes are employed to provide reliable fixation for implants. Electrical properties are characterized to ensure the functionalities for delivering electrical signals to injured nerves. We hypothesize that the stimulator achieves the requirements including (1) reliable functionality during the designed life span and (2) fast degradation afterwards. The second aim of this work examines the role of flexible and bioresorbable microelectronics as an interventional tool for the facilitation of nerve regeneration following injury, and specifically defines the optimal repetition and location of therapeutic electrical stimulation to facilitate functional recovery after nerve repair. Animals undergo 20-Hz therapeutic electrical stimulation by implantable stimulators for 1 hour immediately after sciatic nerve transection and different nerve repair strategies, and the stimulation lasts for different days post-surgery, with various sites including proximal, distal and dual nerve stumps afterwards. Functional assessments and histomorphometry analysis are utilized to evaluate the extent of peripheral nerve regeneration post-operatively. We hypothesize that applying such treatment via wireless bioresorbable implants daily within appropriate time frames and locations will help enhance nerve regeneration and functional recovery