Mason Journals (George Mason Univ.)
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Machine Learning Models of CHI3L1 Mutant Pathogenicity using Computational Mutagenesis
No full textCHI3L1 is a secreted glycoprotein thought to play an active and crucial role in angiogenesis, antibacterial and inflammatory response throughout the body, and stimulation of human connective tissue cell proliferation. Pathogenic CHI3L1 variants were observed in numerous cancers, autoimmune, and inflammatory diseases, including asthma, atoptic dermatitis, rheumatoid arthritis, Alzheimer’s disease, and glioblastoma cancers, among other common poorly treatable conditions. Evaluation of CHI3L1 missense variant pathogenicity is critical to the future of CHI3L1-related drug research and discovery of promising biomarkers. Current knowledge of pathogenic variants is limited to clinical findings with insufficient evidence to confidently validate research, with many findings expressing “possible” or “probable” pathogenic effects of SNPs. Through four structure-based and sequence-based machine learning programs (AutoMute2.0, SNPs & GO3d, MutPred, PANTHER) trained with large numbers of diverse single residue mutations to predict disease potential of SNPs, computational mutagenesis was performed on 7.3k CHI3L1 variants using protein sequence and structure from PDB ID 1hjx. AlphaFold structure AF-P36222-F1 was also run in AutoMute to explore the possibility of predicting the unmapped residues 1-21 from structure 1hjx and for cross-referencing of results from regions with high model confidence; residues 1-21 yielded low confidence results due to the low pLDDT score in that region. CHI3L1 variants assessed at all possible residue positions with limitations of prediction at the positions with less than 6 neighboring amino acid residues. Results display promising baseline for future study of CHI3L1 mutant-prompted pathogenesis. 
Literature Review of Electric Heavy Duty Vehicles and Charging Standards
No full textBattery electric transit buses are a technology experiencing a rapid rise in popularity due to high fuel prices and the need to stop climate change. This literature review will explore the strategies and successes of the rollout of electric buses by transit agencies, different available high power charging standards, the funding for the transition to electric buses and related infrastructure, and the possibility of increased energy density for future batteries. Transit agencies have rolled out battery electric buses with varying rates of success, from one having an exclusively electric fleet to one giving up entirely on battery buses. The three primary charging methods are by cable, by an overhead port, and wirelessly with inductive charging. Transit agencies can take advantage of numerous state and federal grants to upgrade their fleets with new buses and charging stations. There is significant room for improvement in the energy density of lithium ion batteries. 
A high-resolution and efficient system for analyzing and labeling ice images
No full textA well-known issue with our environment is global warming and climate change. The Arctic region is a key indicator that can be used to measure the effects of global warming. Arctic CyberInfrastructure (ArcCI) allows researchers and scientists to study this pressing issue through autonomous classification of aerial ice image data from the Arctic regions. In addition, ArcCI aims to be user-friendly and intuitive, featuring a simple interface that allows for quick labeling of ice structures using labels such as ice, shadows, and water. ArcCI was made to improve image management and processing, specifically for ice data. ArcCI primarily uses object-based image analysis (OBIA) methods with integrated machine learning and high spatial resolution data to accurately label images. A key component of the ArcCI infrastructure is its ability to classify images autonomously due to the various data training models used and the export script which allows for the ability to easily share labeled images. ArcCI helps enhance the accuracy and consistency of ice image analysis. This makes it a valuable asset in a diverse range of applications, from climate studies to ice navigation. 
Variability of Venusian ionospheric electron density as observed by Pioneer Venus Orbiter and Venera 15/16 missions
No full textElectron density varies throughout the Venusian upper atmosphere and differs depending on factors related to time and location, providing an insight into the climate and atmosphere. The Pioneer Venus Orbiter and Venera 15/16 satellites conducted radio occultation experiments to measure electron density variations with atmospheric altitude. Using the archived electron density profiles from Pioneer Venus Orbiter and Venera 15/16, figures of electron density as a function of altitude were created and showed electron density peaks at approximately 140 km above Venus' surface. The electron density peak from the Pioneer Venus Orbiter and Venera 15/16 satellites matched those in publications from the Akatsuki and Venus Express satellites (Hensley et al., 20201; Tripathi et al., 20232). The electron density profiles also showed that the peak electron density varies between 5 x 103 cm-3 and 7 x 105 cm-3, depending on solar zenith angle, latitude, and longitude, demonstrating a strong spatiotemporal variability, which suggests that underlying ionization processes are dependent on these factors. Despite the differences in the peak electron density with latitude, longitude, and solar zenith angle, multiple satellite missions demonstrated that the Venusian ionospheric electron density peaks at approximately 140 km regardless of these factors.
References: 1. Hensley, K., Withers, P., Girazian, Z., Pätzold, M., Tellmann, S., & Häusler, B. (2020). Dependence of dayside electron densities at Venus on solar irradiance. Journal of Geophysical Research: Space Physics, 125, e2019JA027167. https://doi.org/10.1029/2019JA027167 
Developing Atomically Layered Heterostructures as Electrochemical Dopamine Sensors
No full textAtomically thin materials, such as graphene layers, have received an exponentially growing interest for biochemical sensing applications. Their high surface-to-volume ratio and exceptionally tunable electronic properties allow them to respond to specific analytes with high sensitivity. The electrochemical sensing of dopamine, a key neurotransmitter, is an essential analytical tool for studying complex nervous systems. Graphene is a favorable sensing material for dopamine detection due to its strong π−π interaction with the aromatic rings of dopamine. However, the minimal charge density at pristine graphene layers limits the electrochemical kinetics of dopamine electrooxidation. In the study, atomically layered heterostructures composed of graphene and molybdenum trioxide (MoO3) were developed to enhance the electrochemical activity towards dopamine reaction. The high work function of MoO3 induced spontaneous hole doping of graphene, leading to enhanced charge density at the graphene surface. Graphene, hexagonal boron nitride (hBN) and MoO3 were mechanically exfoliated and assembled into heterostructures with a transfer system. The presence of MoO3 in the heterostructure was found to increase the graphene sheet conductance by more than two folds, indicating that charge modulation is effective and beneficial for dopamine detection. This work may pave the way for biosensors that take advantage of the excellent tunability of atomically layered heterostructures. 
Photoluminescence Mapping of Atomically Layered Photocatalysts
No full textLight–driven chemical transformation via interfacial photocatalytic reactions has the potential to revolutionize energy production and sustainable chemical industry. Atomically thin materials offer a promising solution to construct efficient photocatalysts owing to their exceptional tunability of optical and electronic characteristics. In the atomic scale, the photogenerated electrons and holes are bounded as neutral quasiparticles, known as excitons. This excitonic effect limits the utilization of free carriers and results in diminished quantum efficiency in the light–driven redox processes. In this work, van der Waals heterojunctions composed of tungsten disulfide (WS2) and molybdenum disulfide (MoS2) were created to facilitate the transition of excitons into free carriers. Spatially resolved photoluminescence (PL) spectra were obtained to quantify the photoemission from the radiative decay of excitons. At the heterojunction formed by WS2 and MoS2, the strong quenching of PL was attributed to rapid charge separation and exciton dissociation. The results highlight the opportunities to leverage van der Waals heterojunctions to manipulate the excitonic effects for efficient photocatalysis.  
Unified: Establishing a Special Olympics College Club through Classroom Instruction: Unified: Establishing a Special Olympics College Club through Classroom Instruction
No full textUnified Sports is a program through the Special Olympics in which athletes with Intellectual Disabilities (ID) have the opportunity to play sports and socialize with students who do not have an ID (Zhang et al., 2022). Introduced in 1988, Unified Sports is either embedded within a high school or university environment and is typically student led (Townsend & Hassall, 2007). However, there can be many challenges with the initial creation of a Unified Sports program as well as how to keep it sustainable for future generations of students, to have the opportunity to actively be involved in the student club (Hassan et al., 2012).
This manuscript employed an autoethnography in which the primary author used self-reflection to focus on how Sport Management professors can create an experience within their classroom to facilitate the formation of a Unified Special Olympics College Club (Ellis et al., 2011). In addition to the primary author’s self-reflection, the autoethnography incorporated an interview with a Special Olympics representative to better understand how to implement a Unified sports program on a college campus.
This research focused on experiential learning and showcased how Sport Management faculty can work with a non-profit organization to build an inclusive and diverse experience through education, collaboration, and community outreach. This research serves as a guide for future Sport Management programs looking to build partnerships with a non-profit entity and establishes the Unified Model for a Sport Event Management Course (UMSEMC) to help Sport Management instructors hoping to partner with the Special Olympics
