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No full textThe Boyd Carter Papers represent a significant archival collection housed in the Hispanic Studies Collection in Texas Tech University's CMLL building. Dr. Boyd Carter was a distinguished scholar of Latin American literature who was active from the 1940s to his death in 1980. He held professorships at the University of Nebraska, Southern Illinois University, and the University of Missouri before concluding his career at Texas Tech University (1978-1980). Upon joining TTU, Carter donated his extensive archive to the university, including rare books, microfilm collections, bibliographical notes, and periodicals focusing on Latin American literature from 1850-1950, with particular emphasis on the famed Mexican writer Manuel Gutiérrez Nájera
Europa Clipper Thermal System Performance Post STV Correlation vs Early Flight
No full textHared Ochoa, NASA Jet Propulsion Laboratory (JPL) / California Institute of Technology, United StatesFrank Kelly, NASA Jet Propulsion Laboratory (JPL) / California Institute of Technology, United StatesSahar Fazlibesheli, NASA Jet Propulsion Laboratory (JPL) / California Institute of Technology, United StatesICES101: Spacecraft and Instrument Thermal SystemsThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.The Europa Clipper Mission launched on October 14, 2024,
and begun its 5.5-year cruise towards Jupiter. Clipper will
be the first flight system to execute dedicated science
investigations of the Jovian moon Europa. Through its
mission, Clipper will be exposed to a wide range of thermal
environments, including ~0.82AU perihelion, 5.6AU maximum
sun range, and a 9.2-hour Jupiter Eclipse. Additionally,
due to the large sun range during its science campaign and
its use of Solar Arrays as the power source, the thermal
design is intended to be power efficient. Before Launch,
the Clipper spacecraft went over a thorough environmental
test campaign including System TVAC (STV) for thermal
system verification and validation. While the test was
designed to be as flight-like as possible, certain test
constraints (facility size, hardware availability, etc.),
led to some difference from the flight configuration. This
paper provides a summary of the STV campaign, the thermal
model correlation effort, pre-flight expected performance
of the thermal subsystem, and comparison to early
performance in flight
An Economic Evaluation of NFTs: A Systematic Framework for Prediction and Analysis with Other Comparable Assets
No full textThere has been a philosophical debate for decades in understanding the true meaning of art and defining it succinctly. Digital technology has helped the art industry advance and reach new heights, but it has also come with new challenges around fraud, ownership, and valuation. While the art industry is dealing with its challenges, blockchain technology emerged a decade ago to solve shortcomings. It helped the industry to gain new heights and helped with security. However, in the last few years, NFTs (non-fungible tokens) have been born as disruptors of the traditional art industry. It combined blockchain technology and democratized the digital ownership of art without going to any art houses, which helped it gain mainstream attention. However, it quickly fizzled and is soaring again, but there are tons of questions to be answered around its instant rise and fall.
This dissertation proposal seeks first to understand the economics of NFTs and the key macroeconomic factors that impact NFT prices. Next, this research will develop predictive models using these factors by employing autoregression and artificial intelligence technology such as transformers. Then, the NFTs will be compared with other common financial assets to see how they performed using time series forecasting and sensitivity analysis. Finally, existing literature studies of over a decade on NFTs are examined to understand the rise and fall of NFTs with future implications around concerns and opportunities.
The lack of quantitative analysis using macroeconomic factors will be addressed in this multidisciplinary research of NFTs combining art, technology, and finance while employing engineering principles. Finally, the research will help us understand emerging financial assets aided by technology and hysteria with a closer evaluation and analysis of NFTs. This will enable not just stakeholders of NFTs but also other researchers to investigate other financial assets using a multidisciplinary approach. This research will help novice investors understand the factors impacting NFT prices and the value of NFTs using financial strategies such as diversification and hedging. Furthermore, this research will inform the right economic conditions to invest in various financial assets and add literature to the body of knowledge on emerging assets like NFTs
Investigating the Effects of Modifications to Dietary Protein Sources Using Ammonium Hydroxide Enhancement in a Mouse Model for Diet-Induced Obesity
No full textThe mechanisms by which dietary protein sources, and red meat in particular,
help maintain metabolic health, especially during aging and disease, is undervalued.
Furthermore, little is known about the sex-based physiological responses to different
dietary protein sources. The current diet-induced obesity epidemic is critically taxing
human health due to the co-morbidities associated with hyperlipidemia. Dietary
interventions that are affordable and promote adherence are critical to identify. The
potential health benefits, and long-term health impacts of directed dietary protein
modification have yet to be explored. Ammonium Hydroxide Enhancement (AHE) of
red meat products is a USDA approved process insuring food safety for consumers. In
this study, AHE of dietary protein sources (DPS) in a high-fat diet context was
investigated to determine potential metabolic health benefits and impacts to health with
again. To that end, C3H/HeJ (C3H/HeJ) were established as a model for chronic dietinduced obesity to provide a nuanced approach to observing obesity as a chronic disease
state. The potential of AHE to dietary protein to attenuate the effects of chronic DIO
was also explored at the physiological and molecular level. It was found that AHE of a
protein DPS can modulate longevity and mass composition in a sex- and DPS-dependent
manner. Moreover, it was demonstrated that DPS has a strong influence on modulation
to signaling in canonical pathways in the liver transcriptome. This modulation can be
further influenced by the addition of AHE, and that sex is a key contributor to metabolic
outcomes. Metabolite profiles were primarily modified over time by a high-fat (HF)
beef diet with AHE (HFBN) in males. Interestingly, more subtle changes were observed
in females as the result of a HF casein diet with AHE (HFCN). Levels of liver proteins
were also impacted by AHE and DPS. In females, the main changes were observed in
CYP3A4 expression as the result of the HFBN diet. In males, HFBN served to increase
GS levels compared with other diets. Our results taken together, demonstrate a
beneficial role of AHE in mitigating High-Fat Diet-induced, metabolism-associated
liver dysfunction in a sex-dependent manner and in aging
Oxygen from Regolith: The Mini-ROXY Lunar Demonstration Instrument and Mission
No full textAchim Seidel, Airbus Defence and Space, GermanyEmanuele Monchieri, Airbus Defence and Space, GermanyMartin Altenburg, Airbus Defence and Space, GermanyMarkus Franz, Airbus Defence and Space, GermanyTehya Birch, Airbus Defence and Space, GermanyGeorg Pöhle, Fraunhofer Institute for Manufacturing Technology and
Advanced Materials IFAM, GermanyChristian Redlich, Fraunhofer Institute for Manufacturing Technology and
Advanced Materials IFAM, GermanyUday Pal, Boston University, United StatesICES308: Advanced Technologies for In-Situ Resource
UtilizationThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.The ROXY (Regolith to Oxygen and Metals Conversion) molten
salt electrolysis process has been specifically conceived
for oxygen and metal extraction from lunar regolith, and
meets all of the ISRU viability criteria. Mini-ROXY
incorporates all beneficial features of the ROXY process,
specifically porous metal cathodes, an optimized fluoride
salt electrolyte, and YSZ (yttria stabilized zirconia)
solid oxide membrane anodes, in a compact design with very
low resource requirements. Mini-ROXY is therefore ideally
suited for a small-scale lunar demonstration of the ROXY
process.
Preparations of a lunar demonstration mission with a
Mini-ROXY facility are underway, including a mission
concept and development of the Mini-ROXY lunar
demonstrator. We report on the development status and
recent progress of the design of the lunar demonstrator,
and the test status of a lab reactor and cartridges, in
which the electrochemical process will be tested on ground
Unsteady Aerodynamics and Aeroelastic Control of a Fixed-Wing UAV with Shark-skin Inspired Micropillars
No full textUnmanned aerial vehicles (UAVs), particularly small fixed-wing designs, often operate in low Reynolds number regimes, leading to transitional flow separation. Flow-induced vibrations affect performance, stability, and structural integrity, making flow control a critical area of study. This research investigates the aerodynamic effectiveness of bio-inspired sharkskin coatings on a small fixed-wing UAV, the "Switchblade”. The bioinspired coatings consisting of uniformly distributed cylindrical micropillars (70 μm and 140 μm) with diverging-tip structures were applied to the upper wing surface. Wind tunnel experiments were conducted at Texas Tech University’s National Wind Institute, with cruise speeds of 17 m/s and 30 m/s, corresponding to Reynolds numbers based on mean aerodynamic chord of 2.1×105 and 3.7×105, respectively. Static angles of attack ranged from 10° to 17°, with a focus on the stall region.
Aerodynamic performance was assessed using load cell measurements for lift and drag forces, along with wing displacement data obtained through laser displacement sensors. High-speed camera imaging was used to capture aerodynamic forces and structural response for both coated and uncoated experimental cases. Additionally, phase-locked Laser Doppler Velocimetry (LDV) measured streamwise flow at 13° and 15° (stall angles) at two different spanwise locations (the midspan and the tip of the wing) for three different chordwise locations (the leading edge, mid-chord and trailing edge) on the UAV wing. Results indicate that bio-inspired micropillars effectively reduce flow separation and associated vibrations, improving aerodynamic performance at high angles of attack when properly implemented on small fixed-wing UAVs
Surface heated membrane with laser-induced graphene technique for membrane distillation
No full textFreshwater scarcity has become a major concern due to accelerating population growth that increases the demand from the agricultural and industrial sectors. To address the increasing freshwater supply and demand, we need to rely on different desalination techniques. However, existing technologies face challenges while treating waters having high TDS (> 70000 mg/L). Membrane distillation (MD) is a promising technology that can be used to treat hypersaline water. MD is a newer desalination technology requiring a relatively lower operating temperature and is less prone to fouling than pressure-driven processes. An efficient MD process operation requires a porous hydrophobic membrane that prevents liquid intrusion to the permeate side while only allowing water vapor to diffuse through the membrane. However, the lack of a robust hydrophobic membrane and lower energy efficiency requirements limits MD’s true potential. In this context, exploring more robust hydrophobic membranes and devising more innovative solutions to reduce the energy consumption of the MD process have been the subject of extensive research. The primary focus of the research outlined in this dissertation is to propose a novel membrane fabrication technique for developing electroconductive surface-heated membranes and integrating innovative heating techniques that can be used in MD applications.
The synthesis approach for the new membrane includes the phase inversion step to fabricate the polyethersulfone (PES) membrane substrate, followed by CO2 laser ablation. Different membrane substrates with different PES concentrations were fabricated with casting thicknesses of 700 µm. PES membrane substrates were soaked in 10 wt.% CaCl2 after being taken out of the coagulation bath. After drying, CO2 laser ablation was performed while controlling various laser parameters such as power, speed, pulse per inch (PPI), and line per inch (LPI – also known as image density). Different types of laser patterns were studied, which can give electroconductive membranes suitable for surface heating techniques integrating radiofrequency (RF) and Joule heating (JH). During the laser ablation, the polymeric surface of the membrane converts to a three-dimensional, porous conductive graphene, referred to as laser-induced graphene (LIG). Laser parameters significantly impact surface-wetting properties as these parameters control the formation of graphene on the PES membrane substrate. SEM-EDS was performed on the membranes for surface and cross-sectional morphological study, which confirmed a preserved porous structure underneath the LIG. Water contact angles were measured, which show an increase from 60° to 143.6° with increasing laser power. Raman spectroscopy and XPS analysis were also carried out to confirm graphene formation with laser ablation. The prepared LIG membrane was used in conventional VMD first before integrating surface heating. A successful VMD performance was observed, and then surface heating with RF was investigated, which eliminates MD's bulk feed heating requirement. LIG heating capability was studied first in the RF field. LIG materials showed excellent thermal response in the RF field with a maximum steady-state temperature of 500 °C. Unprecedented heating rates, as high as 502 °C/s, were observed when LIG was exposed to RF fields at 200 MHz frequency and 4.6 W power. RF parameter was further optimized for application specific to the VMD membrane module in this work , showing surface average temperature of ~140 °C. The PES-LIG membrane's mechanical and thermal properties are characterized by an investigation of its feasibility for MD application. VMD with RF heating shows permeate flux up to 13.5 L m-2 h-1 with >99% salt rejection. Cyclic thermal and mechanical stability tests and long-term VMD tests were performed, which showed stable performance of the LIG membranes. This work demonstrates a novel MD technique strategy that can potentially address challenges impeding its commercialization.
The surface heating study of VMD was further extended with the JH technique for the PES-LIG membranes. JH requires a different type of laser pattern for enhanced electrical properties of the membrane, which gives a hydrophilic LIG layer. To obtain a hydrophobic surface, PDMS-SiO2 coating was introduced with drop-casting, which gave a water contact angle of 152°, making a superhydrophobic LIG surface. JH in two modes, with direct current (DC) and alternating current (AC), was investigated. It has been found that electrode corrosion on DC JH can be overcome with AC JH. JH technique with the PES-LIG membrane prepared in this work showed successful application in VMD with permeate flux as high as 11.9 L m-2 h-1 with >99% salt rejection
Refined Method for Determining Adhesive Forces of Dust on Aerospace Materials
No full textJoshua H. Litofsky, National Aeronautics and Space Administration (NASA), United StatesSonali R. Nagpal, National Aeronautics and Space Administration (NASA), United StatesAmy M. Fritz, National Aeronautics and Space Administration (NASA), United StatesChandler S. Lawson, National Aeronautics and Space Administration (NASA), United StatesRaj R. Gohil, National Aeronautics and Space Administration (NASA), United StatesCourtney A. Steagall, National Aeronautics and Space Administration (NASA), United StatesRyunosuke Greer, National Aeronautics and Space Administration (NASA), United StatesKenton R.Fisher, National Aeronautics and Space Administration (NASA), United StatesAlejandro D. Rincón, Amentum, United StatesJeremy A. Wilson, Amentum, United StatesMichael E. Urrutia, Amentum, United StatesRonald G. Lee, Booz Allen Hamilton, United StatesEdward Rosenthal, Booz Allen Hamilton, United StatesICES510: Planetary and Spacecraft Dust Properties and
Mitigation TechnologiesThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.In this study, we expand upon a method of quantifying the
force of adhesion of lunar simulant under simulated lunar
surface conditions. This technique applies a monolayer of
dust to a small sample coupon which is then rapidly
rotated; from the size of the simulant grains that remain
on the sample coupon, the force of adhesion of the simulant
can be calculated. These tests, using lunar simulant JSC-1A
across 16 different sample coupon materials, were performed
under vacuum and exposure to ultraviolet light to simulate
lunar conditions. This study demonstrates the ease and
high-throughput with which adhesive forces can be
experimentally determined under lunar conditions across a
wide variety of materials. Improvements upon previous
attempts at quantifying forces of adhesion are shown,
including the addition of an applied acceleration force
degree of freedom and the ability to test multiple
different materials at the same time. Deliverables from
this test include quantitative and experimentally
determined adhesive forces for use in dust transport and
analysis models as well as qualitative metrics to directly
compare the susceptibility of materials to the adherence of
lunar dust. Included forward work outlines hardware
upgrades to improve homogeneity of simulant application and
in-situ simulant particle size analysis
Box 5, Folder 2, Misc. MGN Transcriptions
Full text linkThe Boyd Carter Papers represent a significant archival collection housed in the Hispanic Studies Collection in Texas Tech University's CMLL building. Dr. Boyd Carter was a distinguished scholar of Latin American literature who was active from the 1940s to his death in 1980. He held professorships at the University of Nebraska, Southern Illinois University, and the University of Missouri before concluding his career at Texas Tech University (1978-1980). Upon joining TTU, Carter donated his extensive archive to the university, including rare books, microfilm collections, bibliographical notes, and periodicals focusing on Latin American literature from 1850-1950, with particular emphasis on the famed Mexican writer Manuel Gutiérrez Nájera