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A Pressurized Emergency Shelter for Planetary Surface Operations
Get PDFCameron M. Smith, University of Arizona / Portland State University, United StatesKai Staats, University of Arizona, United StatesTrent Tresch, University of Arizona, United StatesKai Nevers, Independent, United StatesICES403: Extravehicular Activity: Space Suit and Surface
Mobility OperationsThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.With near-future plans for lunar and Mars surface
exploration there is a rapidly expanding effort to design
and develop the many tools, technologies, and systems
required for long-term stays far away from our home. While
automated systems piloted by sophisticated algorithms are
already replacing the traditional pilot and human hand,
exploration by foot is a fundamental function of the human
motivation to visit and eventually live on other worlds
in our solar system. On the surfaces of the Moon and Mars
rovers will carry human explorers to craters and hills
beyond the reach of a pedestrian EVA, demanding that the
exploration team be prepared for catastrophic failure of
one or more systems. We describe the philosophy, design,
fabrication and initial testing of a planetary pressurized
rescue tent (PPRT) that will be demonstrated in a 24-hour
test at the Space Analog for the Moon and Mars (SAM), a
hi-fidelity, hermetically sealed habitat analog and
research facility located at the University of Arizona’s
Biosphere 2. Testing to date has focused on ergonomics and
ease-of-use, employing compressed air as the breathing gas,
a CO2 scrubber, operating pressure of 1.0-2.0PSIG and a
transceiver for communications. Initial tests have been
favorable regarding ergonomics and ease-of-use of the PPRT
while encumbered by a pressurized EVA suit. We are
currently fabricating a second test article for testing
using 100% oxygen at 3.5-4.5PSIG for longer periods
simulating the wait for rescue. Expansion of the concept to
support more than one crew is reasonable for a variety of
planetary surface operations architectures. We build upon
prior ICES publications as the functional research
parameters expand
An Assessment of Volatile Odor Profiles from Polymers used in the Fabrication of Ghost Guns
No full text3-D printed firearms, also commonly known as ghost guns, have been increasingly popular over the past 13 years. One of the reasons it has increased popularity is due to these weapons’ untraceable nature. The increasing popularity leads to a growing concern about public safety. The current detection methods used to identify conventional firearms, such as metal detectors and canines, aren’t a viable detection method that can be used for identifying this upcoming threat of ghost guns. Since ballistic examiners can't rely on traditional methods for examining striation marks, as ghost guns don't produce these markings, there is a dire need to explore alternative techniques for analysis. It’s imperative to understand the odor signatures from various polymers and their various brands and colors to possibly add another technique to the ballistic examiners’ toolbox, that could possibly allow for the examiners to create associative links between a crime and a ghost gun.
The objectives of this study were to: 1) conduct and analyze the odor profile of various polymers before and after printing, and 2) conduct and compare chemical characterizations of the headspace of a 3-D printed Liberator before and after discharge.
This study utilized solid phase micro-extraction (SPME) coupled to gas-chromatography/ mass spectrometry (GC/MS) technique to conduct the headspace sampling of the various polymers and Liberators. For the first objective, the sampling took place using either filament cut directly from the spool (n=10) and 3-D printed polymer blocks (n=10 ) for each of the 5 colors of one brand and two colors of the second brand. For the second objective, the headspace sampling of the Liberator prototype took place before and after the firing discharge.
Highly occurring compounds were deemed those present across 7 or more samples across one polymer type and condition (pre-print and post-print). These functional groups of compounds deemed as high occurring included alcohols, aldehydes, alkanes, alkenes, benzenes, carboxylic acids, ketones, and diesters. The odor analysis showed that there were a few unique compounds for the two-brand analyzed during the study.
This study will provide a framework for foundational data for odor profiles of various polymers and their respective brands and colors. While there are several studies that have looked at the health effects of volatile emissions during 3-D printing processes, there is a lack of studies that have chemically characterized common polymers used for ghost gun manufacturing using headspace sampling techniques. This study attends to a research gap by using SPME-GC/MS to evaluate odor profiles of various polymers before and after print, as well as before and after discharge of a 3-D printed firearm to combat an evolving national security threat
Detection of Di- and Tri-Locus kdr Mutations in Aedes aegypti and Aedes albopictus from Texas, USA, and the Implications for Insecticide Resistance
Get PDFDuring the last 20 years, there has been increasing concern about inefficient vector control efforts due to insecticide resistance. A common mechanism causing insecticide resistance is mutational changes in the voltage-gated sodium channel, deemed knockdown resistance (kdr), resulting from continued pyrethroid application. Although closely related, there have been documented kdr differences and frequencies between Aedes aegypti and Aedes albopictus. Individual Ae. aegypti and Ae. albopictus from five counties in Texas, USA were tested using four single nucleotide polymorphisms genotyping assays to assess the kdr (F1534C, V1016I, V410L, and S989P) differences between the two species. Each mutation was analyzed independently by calculating frequencies and analyzing the difference using a Wilcox Rank Sum test. Significant differences were observed between Ae. aegypti and Ae. albopictus when comparing F1534C and V410L (p-value < 0.0001). Knockdown resistant mutation V1016I was not different between the two species. Individuals from both species had di-locus mutations, and individuals from Ae. aegypti had tri-locus mutations detected in combinations that have been reported to influence insecticide resistance. Given our findings, one can speculate that populations of both species are resistant to pyrethroids, thus likely limiting the success of control methods
Immunological Mechanisms, Cellular Processes, and Hindgut Interactions in the Development of Liver Abscesses in Cattle: A Molecular and Cellular Analysis
Get PDFLiver abscesses are a major health concern in feedlot cattle, often linked to dietary practices and microbial translocation due to compromised epithelial barriers. This thesis explores the immunological, molecular, and epithelial mechanisms involved in liver abscess formation, with the overarching goal of advancing preventive strategies and reducing reliance on prophylactic antimicrobials. In Chapter I, a comprehensive literature review contextualizes the roles of Fusobacterium necrophorum, Trueperella pyogenes, and Salmonella enterica in liver abscess pathogenesis, highlighting epithelial dysfunction, bacterial virulence, and host immune responses. Chapter II presents a transcriptomic analysis of hepatic tissues from experimentally challenged Holstein steers, revealing distinct gene expression profiles in animals that developed abscesses versus those that resisted infection. Findings point to an association between liver abscess development and upregulation of inflammatory and fibrotic pathways, while resistance was linked to immunometabolic balance. Chapter III details the development and validation of a protocol for isolating and culturing primary bovine gastrointestinal epithelial cells (PBGIECs), confirming epithelial identity through gene expression of key markers (CDH1, CLDN4, TJP1, KRT8, KRT18) across different segments (rumen, ileum, jejunum, colon) and stages (tissue, post-isolation, post-culture). Variations observed suggest segment-specific gene sensitivity and emphasize the influence of in vitro conditions, including cell passage number and tissue dissociation. Collectively, this work provides novel insights into host-pathogen interactions, epithelial biology, and hepatic responses in liver abscess development, offering a foundation for future research on bovine health management and antimicrobial alternatives
Enhancing Opinion Mining in E-Commerce: The Role of Text Segmentation and K-Means Clustering in Transformer-Based Consumer Trust Analysis
No full textAs the E-commerce market expands, customer reviews have become essential for companies aiming to understand consumer opinions. Building consumer trust is critical to the success of E-commerce businesses, as it significantly influences purchasing decisions. Understanding how to build this trust is essential, especially given that 93% of consumers report that online reviews influence their purchasing choices.
Trust in E-commerce is commonly understood as a consumer’s willingness to rely on an online seller based on expectations of reliability, security, and competence. In other words, various factors affect consumer purchase decisions when shopping online. Customer reviews are crucial for gauging consumer opinions and can help identify the factors influencing trust in online shopping. However, current research primarily focuses on using transformer models to classify reviews as positive, negative, or neutral or to predict customer ratings based on the content of those reviews.
This dissertation introduces a new approach that expands the capabilities of pre-trained transformer models, such as GPT, BART, and BERT, to extract trust factors from customer reviews, addressing a significant gap in the current literature. The research notably improves the model’s accuracy by utilizing text segmentation. Comparative analysis between segmented and unsegmented datasets, benchmarked against manually annotated reviews, demonstrates that text segmentation increases accuracy. Specifically, GPT-3.5 achieved an accuracy of 86.9%, representing a 15.5 percentage point improvement over unsegmented data. These findings validate segmentation as a critical technique for enhancing granularity and enabling models to identify nuanced trust factors effectively.
To further validate the effectiveness of our approach, a second experiment was conducted using a different dataset to determine whether segmentation would yield comparable or even better performance in terms of accuracy. In this experiment, text segmentation was applied before the initial factor extraction to enhance the identification of trust factors. However, the large number of extracted factors created new challenges, as many were redundant or represented similar concepts under different names, complicating large-scale analysis. To address this challenge, K-means clustering, combined with the elbow method, successfully standardized the 2,890 extracted factors and grouped them into nine key categories. This refined process further improved the GPT-3.5 model’s accuracy to 88.5%, demonstrating the scalability and robustness of the proposed methodology in handling large-scale review datasets.
The findings highlight the centrality of text segmentation and underscore the crucial role of normalization techniques, particularly K-means clustering, in managing large-scale review datasets. By offering a scalable and adaptable framework, this dissertation provides actionable insights for improving E-commerce analytics. Furthermore, it lays the groundwork for broader applications, extending its suitability beyond E-commerce to other areas where manual labeling is challenging or resource-intensive
Artemis Suit Material Project Overview
No full textRobert J. Jones, Leidos / KBR HHPC / NASA Johnson Space Center(JSC), United StatesShane McFarland, Aegis Aerospace / KBR HHPC / NASA Johnson Space Center(JSC), United StatesStephanie Rodgers-Ahnen, Textile Made, United StatesRichard Rhodes, NASA Johnson Space Center(JSC), United StatesICES400: Extravehicular Activity: Space SuitsThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.This paper presents an overview of an ongoing NASA
technology infusion project aimed at designing,
fabricating, and testing a new outer shell fabric for a
lunar Extravehicular Activity (EVA) space suit, crucial for
sustained lunar exploration. Historically, fabrics such as
Beta cloth (Apollo missions) and Ortho Fabric (used on the
current Extravehicular Mobility Unit, EMU) have provided
essential protection in space. However, both materials have
been found to be inadequate for long-duration lunar
missions due to challenges posed by the lunar environment,
particularly abrasive lunar dust and cryogenic flexibility.
The goal of this project is to develop a more robust and
dust-resistant fabric suitable for sustained lunar surface
operations as part of NASA’s Artemis program. The scope is
multi-faceted, and a broad overview will be presented here.
Detailed results including down selection and test data are
planned to be presented in a future publication. The
project's methodology includes evaluating commercially
available textiles and coatings to better inform the design
and development of a bespoke fabric solution to better meet
the stringent requirements for lunar EVAs. This paper will
focus on the approach taken to develop a set of
comprehensive requirements that guide material selection,
testing, and validation. These requirements encompass
protection against dust infiltration, thermal regulation,
durability, and flexibility to name a few. Initial
development involves a thorough vetting process of
existing, commercially available materials, coupled with
the evaluation and evolution of new technologies, to
produce a high-performance fabric capable of sustaining
prolonged exposure to the lunar environment. The insights
gained from this research will inform future development
cycles and play a critical role in advancing EVA suit
technology for long-term lunar exploration
Study on Applicability of New Adsorbent CeO2 to CO2 Removal Systems Resulting in Decrease of Volume, Weight, and Power Consumption
No full textKazuhiro Toda, Japan Aerospace Exploration Agency (JAXA), JapanAsuka Shima, Japan Aerospace Exploration Agency (JAXA), JapanMasato Sakurai, Japan Aerospace Exploration Agency (JAXA), JapanICES302: Physico-Chemical Life Support- Air Revitalization
Systems -Technology and Process DevelopmentThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.This paper presents a feasibility study on the use of
cerium oxide (CeO2) as a novel adsorbent in CO2 removal
systems for cabin air revitalization. CeO2 offers potential
advantages because its CO2 adsorption capacity remains
stable in the presence of water vapor, and CO2 desorption
can occur at lower temperatures compared to conventional
zeolite 13X. These characteristics suggest that a
CeO2-based system may reduce the overall volume, weight,
and power consumption of CO2 removal units. A CO2 removal
test was conducted using a prototype model incorporating
the CeO2 adsorbent, and fundamental data on its adsorption
and desorption performance were obtained. This paper
discusses the results of this evaluation
Exploration of Vertical Holes Near the Lunar Polar Regions to Confirm the Presence of Water in Underground Caves and Their Utilization
No full textMasato Sakurai, Japan Aerospace Exploration Agency (JAXA), JapanNao Hoshinouchi, Osaka University, JapanNao Shinohara, Japan Aerospace Exploration Agency (JAXA)/ISAS/The Graduate University for Advanced Studies, JapanJunichi Haruyama, Japan Aerospace Exploration Agency (JAXA)/ISAS, JapanICES506: Human Exploration Beyond Low Earth Orbit: Missions
and TechnologiesThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.Japan has identified underground caves on the Moon near the
lunar equator, likely associated with large vertical holes
caused by past volcanic activity. Additionally, lava tubes
formed by meteorite impacts have also been observed near
the polar regions. The confirmation of water stored as ice
is considered a primary motivation for exploration,
particularly near the Moon’s south pole. Potential sources
of this water include asteroid impacts and the solar wind.
While significant quantities of water have yet to be
detected on the lunar surface, these underground caves,
shielded by substantial overhangs and in permanent
darkness, are considered locations where water stored as
ice is expected to accumulate due to its difficulty in
escaping. This paper outlines a proposed mission to
investigate areas near these polar holes throughout the
lunar day, finding a traversable route by land from a
prospective landing site to these polar vertical holes and
considers methods of investigating the interior of shallow
vertical holes. Furthermore, this paper examines possible
missions within the lunar landing plan currently being
developed for the NASA-led Artemis program. Based on
information about the program, we consider the feasibility
of Japan independently exploring and utilizing the Moon.
Artemis III, which plans to have nine landing sites near
the south pole and is expected to use Starship for landing,
and JAXA’s ongoing development of a pressurized manned
rover, will significantly facilitate valuable lunar
exploration
Validation of Virtual Synchronous Machine (VSM) Technology for Solar Energy Applications
No full textThe rapid adoption of photovoltaic (solar) energy is driving a fundamental shift from centralized generation toward decentralized Distributed Energy Resources (DERs) integrated through power electronic converters, known as inverter-based resources (IBRs). Solar energy has emerged as a crucial component in addressing climate change, meeting global sustainability targets, and providing reliable, affordable, and modern energy access to all. However, integrating IBRs capable of operating in both off-grid and grid-tied modes presents significant technical challenges, primarily due to the need to replicate the physical properties and control behaviors of traditional synchronous machines used in centralized power plants. Virtual Synchronous Machine (VSM) technology represents a promising solution to these challenges by embedding the dynamic behaviors and inherent synchronization capabilities of synchronous machines within IBRs, offering enhanced control flexibility and enabling autonomous operation. This study investigates the application, integration, and rigorous experimental validation of VSM technology across solar energy systems, from individual off-grid units to large-scale grid-integrated scenarios. Experimental validation began with the design, simulation, and field testing of a portable off-grid solar generation unit employing a VSM-based power converter coupled with energy storage. Further experimental studies demonstrated effective parallel operation, precise power sharing, and self-synchronization mechanisms among multiple off-grid solar systems enhanced with plug-and-play capabilities. The scalability and versatility of VSM technology were then evaluated through the development and validation of the TTU 108-Converter Autonomous Smart Grid Testbed, which integrates physical solar panels, wind turbine emulators, battery storage systems, and flexible loads. This testbed emulates an autonomous, large-scale community power system capable of operating entirely on renewable sources while seamlessly transitioning between grid-tied and off-grid modes. Experimental results confirm that VSM-enabled converters effectively maintain strict voltage and frequency regulation compliant with utility standards, achieve accurate power sharing among interconnected IBRs, support seamless transitions between off-grid and grid-tied operation modes, and exhibit robust black-start and self-synchronization capabilities. Overall, this research provides rigorous experimental validation of an advanced power electronics control approach to addressing key challenges in integrating solar energy systems within modern energy infrastructure, significantly enhancing their reliability, scalability, resilience, and safety