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Does Chronic Expression of E4orf1 Improve Risk Factors and Cognition Decline in a Mouse Model of Obesity-Associated Alzheimer's Disease?
No full textA key pathophysiological factor in obesity, type 2 diabetes (T2D), and Alzheimer's disease (AD) is insulin resistance. Insulin resistance, characterized by hyperglycemia and hyperinsulinemia, contributes to AD by raising AGEs, reducing synaptic plasticity, and enhancing oxidative stress and neuroinflammation. Despite obesity, the novel adenoviral protein E4orf1 enhances glycemic control and protects against the buildup of liver fat independent of insulin. We hypothesize that E4orf1 will slow the onset and progression of AD by improving insulin-related risk factors. In an older AD mouse model, we previously demonstrated that E4orf1 improves metabolic function and cognition. Here, we used an obesity-related transgenic mouse model of AD that expressed E4orf1 protein specifically in adipose tissue upon doxycycline feeding. Following baseline systemic (body weight, EchoMRI, oral glucose tolerance test, insulin, hemoglobin A1c) and behavioral (Y-maze and Morris Water Maze (MWM)) analyses, mice aged four to six months were given a 60% high-fat diet. These mice were classified as WT (n=20), APP/PS1 (n=14), and APP/PS1 expressing E4orf1 (n=11). A cohort of mice was sacrificed, and investigations were conducted again four months later. The remaining animals were sacrificed after the analyses were repeated eight months later. Western blot and RT-qPCR were used for molecular pathway analysis in the brain, liver, and adipose tissue. ELISA was used to assess biomarkers from plasma samples.
Despite a high-fat diet, E4orf1 expression significantly decreased HbA1c, decreased endogenous insulin needs for glucose clearance, reduced body weight, and improved habituation and spatial memory in Y-Maze and MWM tests, even though APP/PS1 mice are prone to AD. E4orf1 downregulated the expression of genes involved in triglyceride synthesis, fatty acid transport, fat oxidation, and lipogenesis in the liver. It significantly upregulated genes linked to fatty acid transport, β-oxidation, and TG production in adipose tissue. E4orf1 had no distinct impact in the brain, indicating that it has no direct effect on the brain. However, as demonstrated by a decrease in plasma Aβ concentration, E4orf1 markedly decreased the peripheral amyloid beta (Aβ) burden. AD currently has no known cure, and the only treatments available are symptom management. E4orf1 can be a potential drug candidate to serve as an insulin-independent agent for AD
Establishing an Oceanic Environment in Space: A “Core-Biome” for Isolated Ecosystems
No full textMiu Shimizu, Kyoto University GSAIS, JapanFumihiko Nagata, Aquarium Management Center, Okinawa Churaumi Aquarium,
Okinawa Churaumi Foundation, JapanYosuke Yamashiki, Kyoto University GSAIS, JapanICES500: Life Science/Life Support Research TechnologiesThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.This study aims to establish an oceanic environment
suitable for space as a critical component of the
terrestrial ecosystem, termed the "Core-Biome." The
Core-Biome represents an essential habitat for supporting
human life in isolated environments. Among terrestrial
ecosystems, the ocean remains the last frontier to be
replicated in space due to the following challenges;
difficulties in managing saline water in closed systems it
is unsuitable for direct consumption or agricultural
irrigation, challenges in maintaining water quality,
essential for cultivating aquatic organisms, and the
complexity of identifying primary producers within the
ocean ecosystem. In our study, we aim to cultivate corals
in a closed ecosystem by introducing three distinct
species: Porites cylindrica (a common species found in the
Okinawa region), Acropora tenuis (known for its thin
branches and resilience to shock compared to other Acropora
species), and Acropora intermedia (a branching Acropora
species commonly found near Iriomote Island). We
established a closed aquarium system where water is
recycled using a protein skimmer and a calcium reactor,
with partial water replacement when necessary. Growth rates
for each coral species were measured under controlled
conditions, maintaining a uniform temperature of 27°C and a
diurnal light cycle. Dissolved oxygen levels were sustained
solely through photosynthesis by coral-associated
zooxanthellae. The material balance, optimal growth
conditions, and key findings from this study will be
presented at the conference
Essays in Health and Labor Economics
No full textThis dissertation aims to examine the effects of economic and policy factors on individual health and labor market outcomes using micro level data from the United States. Study one examines the effects of state level minimum wage changes alongside Medicaid expansion, as part of the Patient Protections and Affordable Care Act, on an individual's decision to invest preventative healthcare and mental health. Through the use of a continuous difference in difference model it finds that minimum wages improve mental health for both males and females. In addition, it finds that Medicaid expansion leads to an increased prevalence in annual checkups and annual flu shot adherence for both genders as well.
Study two examines the effects of state level minimum wage changes on infant birth outcomes of younger and older mothers. Through the use of a continuous difference in difference model with a rich set of control variables including demographics, birth characteristics, insurance coverage and state-year time fixed effects it finds mixed results across mothers of different age ranges. It finds that minimum wages have limited effects on decreasing adverse birth outcomes for teenage mothers, but show a larger impact for older mothers in their twenties and thirties on Medicaid.
Finally, study three examines the demographic makeup of both discouraged and marginally attached workers over a thirty year time period from 1994 - 2024. It finds that the proportion of these workers with less than a high school diploma has been decreasing, while the proportion with a high school diploma or GED as their highest level of education has been increasing. It also finds that a slightly larger proportion of marginally attached workers report being male. These three studies aim to closely examine the effects that different policies, economic factors, and demographic characteristics have on health and labor market outcomes
Status of the Advanced Oxygen Generation Assembly
No full textKevin Takada, National Aeronautics and Space Administration (NASA), United StatesAllen Williams, Leidos, United StatesDavid Hornyak, National Aeronautics and Space Administration (NASA), United StatesJohn Garr, National Aeronautics and Space Administration (NASA), United StatesSteven Van Keuren, S&K Global Solutions, Inc., United StatesOmoniyi Obashe, The Boeing Company, United StatesAbdelrahman Elsherbini, Collins Aerospace (an RTX Business), United StatesChristopher Williams, Amentum, United StatesJackson Kinney, Amentum, United StatesICES302: 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.Future Exploration missions will require an Oxygen
Generation Assembly (OGA) to electrolyze water to supply
oxygen for crew metabolic consumption. The system design
will be based on the International Space Station (ISS) OGA
but with added improvements based on lessons learned during
ISS operations and technological advances since the
original OGA was designed and built. The goal of these
improvements will be to reduce spares mass and crew
maintenance time while increasing reliability. These
improvements will be incorporated into the Advanced OGA
(AOGA), which will be launched to ISS in 2026 and its
operation demonstrated in a relevant flight environment for
at least 3 years. AOGA upgrades include: redesign of the
electrolysis cell stack, redesign of the hydrogen dome,
replacement of the hydrogen sensors, redesign of the
recirculation loop deionizing bed, and incorporation of
recirculation loop nitrogen purging and water flushing.
AOGA design reviews, analyses, and development tests are
now complete. Currently, AOGA flight hardware components
are being manufactured. The design, build and plans for
the AOGA will be reviewed in this paper
Developing Photobioreactors for Microalgae Cultivation on the Moon – Technical Challenges, Research Plan and First Steps
No full textLina Salman, Technical University of Munich, GermanyGisela Detrell, Technical University of Munich, GermanySergio Santaeufemia, Technical University of Munich, GermanyFabio Schäfer, Technical University of Munich, GermanyICES204: Bioregenerative Life SupportThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.Space agencies and commercial companies aim to go back to
the Moon with the objective to eventually stay and build a
permanently crewed lunar settlement. As these plans move
forward, the need for sustainable life support systems that
promote recycling and reduce resupply missions from Earth
will become increasingly important. Among potential
solutions, microalgae offer a promising approach to closing
the loop due to their photosynthetic capabilities and
efficient cultivation in photobioreactor (PBR) systems.
While PBR systems to cultivate microalgae on Earth are
being optimized for terrestrial gravity, these systems
require significant adaptation for lunar application to
ensure efficient algae cultivation for a long-term and
large-scale human settlement. Cultivating microalgae in the
lunar environment presents substantial challenges due to
the Moon’s unique environmental conditions, such as reduced
gravity, and mission related requirements, such as reduced
crew time and limited resources. Therefore, this paper aims
to provide a research plan on how to overcome the technical
challenges involved in designing a PBR suitable for
long-term and large-scale lunar habitats. Consequently, the
technical challenges of the PBR and its subsystems
regarding the integration and use in a large-scale lunar
base are analyzed in this paper. Based on that, a research
plan by the Professorship of Human Spaceflight Technology
at the Technical University of Munich is outlined, which
aims at developing a lunar-gravity adapted PBR system for a
long-term and large-scale crewed lunar base. Initial
efforts in developing the PBR system with its corresponding
subsystems are presented and discussed. The proposed
research activities and initial efforts represent a
critical step towards developing a viable and efficient PBR
system that supports a long-term and large-scale human base
on the Moon
Optimization and Application of LC-MS/MS Techniques for Characterizing Glycans, Proteins, and Metabolites in Complex Biological Samples
No full textProteomics is a large-scale study of proteins within a cell, tissue, or organism under specific physiological conditions. It involves analyzing protein expression, structure, functions, interactions, and modifications, providing critical insights into biological regulation in both health and disease. As a key component of disease biomarker research, proteomics is particularly important for understanding complex disorders. Among post-translational modifications, glycosylation is one of the most prevalent and functionally significant, influencing protein stability, signaling, immune responses, and cell-cell interactions. Aberrant glycosylation patterns are associated with various diseases, including neurodegenerative disorders and cancers, where specific glycan and glycopeptide isomers serve as potential biomarkers. Metabolomics, the study of small-molecule metabolites involved in cellular processes, complements proteomics by offering a snapshot of an organism’s physiological state. As part of the multi-omics framework, metabolomics follows the genome, transcriptome, and proteome, providing a comprehensive view of disease progression and metabolic regulation.
Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a powerful analytical platform for characterizing proteins, glycoproteins, glycans, and metabolites, offering high sensitivity and resolution. This dissertation presents advancements in LC-MS/MS methodologies to enhance biomolecular characterization. A FAIMS-assisted approach was developed to improve the separation of permethylated glycan isomers, while mesoporous graphitized carbon (MGC) chromatography combined with ultraviolet photodissociation enabled enhanced structural characterization of glycopeptide and glycan isomers. Additionally, an isotopic labeling strategy was established to facilitate the simultaneous analysis of up to sixteen glycomics samples in a single run. A label-free, bottom-up proteomics workflow was optimized and applied to investigate the cognitive and cardiovascular effects of antidiabetic drugs, including DPP4 and SGLT2 inhibitors, in type 2 diabetes patients with mild cognitive impairment. Furthermore, comprehensive serum metabolomics profiling of narcolepsy type 1 (NT1) patients was conducted to identify potential disease markers.
By integrating advanced LC-MS/MS techniques into proteomics, glycomics, and metabolomics research, this work contributes to biomarker discovery, disease characterization, and therapeutic development, reinforcing the critical role of multi-omics approaches in modern biomedical science
A cultural adaptation of Tinto’s student integration theory in undergraduate students of a private university in Colombia
No full textDropout in higher education is a phenomenon of interest in both developed and developing countries; therefore, it is highly relevant to validate models that seek to explain it. This study aimed to determine the risk of dropping out in the first year using Tinto’s integration model, which incorporates students’ entry characteristics and aspects of institutional commitment and academic and social integration (SI) in the university environment. A prospective cohort study was conducted with 563 students enrolled in the 2019-1 and 2019-2 cohorts. Entry variables (demographic, socioeconomic, family and psychosocial) were measured, as well as the constructs of institutional commitment, academic and SI at two points in time, and dropout in the first year. Confirmatory factor analysis (CFA), factorial invariance over time, and structural equation modeling (SEM) were performed for the analyses. Family and psychosocial variables best explained the initial commitment of students. The initial commitment had significant effects on academic and SI, as well as on the subsequent commitment of the student, which, in turn, had a significant effect on the decrease in dropout rates. In conclusion, Tinto’s model was supported for explaining the dropout rate in Colombian university students, suggesting that beyond the student’s entry attributes, the interactions the student has with the academic and social system are critical to retention
Martian Exploration Portable Life Support System Schematic Study
No full textDana M. Lobmeyer, Amentum, United StatesMadeleine Oliver, Amentum, United StatesEmma J. Quick, Amentum, United StatesOlivia J. Lawson, Amentum, United StatesLawrence W. Barrett, Amentum, United StatesBruce C. Conger, Amentum, United StatesCinda Chullen, NASA Johnson Space Center (JSC), United StatesColin Campbell, NASA Johnson Space Center (JSC), United StatesICES402: Extravehicular Activity: PLSS SystemsThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.The Mars environment poses unique challenges for portable
life support system (PLSS) technologies supporting
extravehicular activities (EVA) that necessitate
modifications to the NASA baseline exploration PLSS (xPLSS)
design. This work details a landmark schematic study
conducted to identify and recommend the most promising
Martian Exploration PLSS (mxPLSS) architectures for
consideration and further evaluation. Conducted from
January 2024 to September 2024, the study began with a
blank sheet approach to pinpoint technologies that could
potentially satisfy each mxPLSS major function. A
comprehensive list of over 80 technologies was compiled.
These technologies were filtered down based on mxPLSS
guidelines established during the project and a preliminary
equivalent system mass (ESM) analyses under nominal Martian
environmental conditions. By considering only unique
combinations of the most feasible technology options, seven
mxPLSS schematics with the lowest overall mass were
identified. Evaluation and comparison of each schematic was
subsequently performed using a newly developed PLSS sizing
tool: the Guided Utility Sizer (GUS). This paper summarizes
the study approach, schematic selection process, and final
assessment that culminated in three different schematic
recommendations. Recommended mxPLSS schematics are
described relative to the vehicle architecture they would
require
Development of the Crew State and Risk Model for Autonomous Biomedical Physiology State Monitoring and Prediction During Exploration Extravehicular Activities
No full textBradley T. Hoffmann, KBR, United StatesKyoung Jae Kim, KBR, United StatesDillon Frisco, JEStech, United StatesLori Cooper, JEStech, United StatesCrystal Kirkley, NASA Ames Research Center (ARC), United StatesAlejandro Garbino, GeoControl Systems, United StatesKarina Marshall-Goebel, NASA Johnson Space Center (JSC), United StatesDaniel Buckland, NASA Johnson Space Center (JSC), United StatesICES513: Human Health and Performance AnalysisThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.NASA has completed hundreds of microgravity spacewalks or
extravehicular activities (EVA) over multiple decades and
spaceflight programs. During the Apollo program, only 14
EVAs were conducted on the surface of the moon. The Artemis
program aims to return to the moon for sustained human
presence necessitating a new paradigm of surface EVA
operations. Current microgravity EVAs and planned Artemis
surface EVAs will rely on ground operations teams with near
real-time communication (i.e., 10-15 seconds roundtrip
delay); however, future Mars exploration will require crew
to conduct EVAs at a full level of autonomy. The Crew State
and Risk Model (CSRM) is being developed to enable
autonomous biomedical support through monitoring and
predicting crewmember physical and cognitive state during
EVA.
The CSRM is a collection of seven core EVA physiology
domains and are developed using empirical data modeling
approaches. Each model subcomponent is developed and tested
as crew member individualized models from EVA training
analog data. The metabolic energy model estimates metabolic
rate profiles from expected planetary EVA tasks. Levels of
carbon dioxide (CO2) inspired within a suit are estimated
through the inspired CO2 model. The human thermal
regulation model predicts core body temperature and heat
storage at < 3% error. The fatigue model estimates time and
probability to physical exhaustion while EVA task
performance predicts cognitive effectiveness and vigilance.
Metabolic cost due to suited ambulation along an EVA path
is generated using the traverse model. Hydration and
nutrition status are predicted using the hydration,
nutrition, and waste management model for readiness and
recovery. Finally, the decompression sickness (DCS) model
estimates risk and sensitivity to DCS based on mission
profiles. Wholistically, CSRM predicts states through
physiology determinants of performance between model
interactions. This paper presents the architecture of the
CSRM and details individual model development and
proficiency in predictions of EVA physiology