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Identification Of Alkynyl Nicotinamide Hsn748 As A Ret Solvent-Front Mutant Inhibitor With Intracranial Efficacy, Ujjwol Khatri, Neetu Dayal, Kofi B Owusu, Mandeep Kaur Hunjan, Shriya Pandey, Haley Anne Harper, Carli Mcmahan, Bennett D Elzey, Tao Shen, Xueqing Hu, Kurt W Evans, Ahmed El-Sheikh, Seong Jun Jo, Frederick W Holtsberg, M Javad Aman, Funda Meric-Bernstam, Sukyung Woo, Herman O Sintim, Jie Wu Aug 2025

Identification Of Alkynyl Nicotinamide Hsn748 As A Ret Solvent-Front Mutant Inhibitor With Intracranial Efficacy, Ujjwol Khatri, Neetu Dayal, Kofi B Owusu, Mandeep Kaur Hunjan, Shriya Pandey, Haley Anne Harper, Carli Mcmahan, Bennett D Elzey, Tao Shen, Xueqing Hu, Kurt W Evans, Ahmed El-Sheikh, Seong Jun Jo, Frederick W Holtsberg, M Javad Aman, Funda Meric-Bernstam, Sukyung Woo, Herman O Sintim, Jie Wu

Faculty, Staff and Student Publications

RET solvent-front G810C/R/S mutations confer resistance to the currently approved RET protein tyrosine kinase inhibitors (TKIs) selpercatinib and pralsetinib. Moreover, RET fusion-positive lung adenocarcinoma frequently metastasizes to the brain. To address these challenges, it is imperative to develop a RET TKI that is effective against solvent-front mutations and exhibits intracranial activity. We synthesized alkynyl nicotinamide-based RET TKIs and tested their efficacy in cell cultures in inhibiting selpercatinib/pralsetinib-resistant RET solvent-front mutants G810C/R/S found in cancer patients, and in BaF3/KIF5B-RET(G810C) cell-derived subcutaneous and intracranial tumors in vivo. We also evaluated alkynyl nicotinamide RET TKIs in KIF5B-RET-induced lung tumors in immune competent …


Reduced Computed Tomography Scan Speed Improves Alignment Errors For Patients Undergoing Thoracic Stereotactic Body Radiation Therapy, Ramaswamy Sadagopan, Rachael M Martin-Paulpeter, Christopher R Peeler, Xiaochun Wang, Paige Nitsch, Julianne M Pollard-Larkin Aug 2025

Reduced Computed Tomography Scan Speed Improves Alignment Errors For Patients Undergoing Thoracic Stereotactic Body Radiation Therapy, Ramaswamy Sadagopan, Rachael M Martin-Paulpeter, Christopher R Peeler, Xiaochun Wang, Paige Nitsch, Julianne M Pollard-Larkin

Faculty, Staff and Student Publications

Objectives: We investigated the performance of a slow computed tomography (CT) protocol to reduce alignment errors arising from motion when using CT-on-rail (CTOR) for image guidance for patients receiving thoracic stereotactic body radiation therapy (SBRT).

Methods: A Quasar lung phantom with a moving tumor was programmed with three breathing rates and three motion amplitudes. MIP and average 4DCT images were used for contouring and alignment, respectively. Ten CTOR images were obtained for each of the breathing rates and amplitudes, under both CT protocols. We used in-house CAT software for image guidance, centering the tumor in the lung window …


Defining Treatment-Resistant Bipolar Depression: Recommendations From The Isbd Task Force, Eduard Vieta, Roger S Mcintyre, Trisha Suppes, Tamsyn E Van Rheenen, Balwinder Singh, Kamilla Woznica Miskowiak, Allan H Young, Lakshmi N Yatham, Kyooseob Ha, Michael Berk, Holly A Swartz, Chantal Henry, Maja Pantovic Stefanovic, Gerard Anmella Diaz, Aysegul Ozerdem, Wiesław J Cubała, Diego Hidalgo-Mazzei, Mauricio Tohen, Isabella Pacchiarotti, Paula Villela Nunes, Carlos Lopez-Jaramillo, Ana Gonzalez-Pinto, Paolo Brambilla, Robert Post, Jair C Soares, Michael Bauer, Ana C Andreazza, Xavier Justes Fradera, Montserrat Cosials-Lopez, Giovanna Fico Aug 2025

Defining Treatment-Resistant Bipolar Depression: Recommendations From The Isbd Task Force, Eduard Vieta, Roger S Mcintyre, Trisha Suppes, Tamsyn E Van Rheenen, Balwinder Singh, Kamilla Woznica Miskowiak, Allan H Young, Lakshmi N Yatham, Kyooseob Ha, Michael Berk, Holly A Swartz, Chantal Henry, Maja Pantovic Stefanovic, Gerard Anmella Diaz, Aysegul Ozerdem, Wiesław J Cubała, Diego Hidalgo-Mazzei, Mauricio Tohen, Isabella Pacchiarotti, Paula Villela Nunes, Carlos Lopez-Jaramillo, Ana Gonzalez-Pinto, Paolo Brambilla, Robert Post, Jair C Soares, Michael Bauer, Ana C Andreazza, Xavier Justes Fradera, Montserrat Cosials-Lopez, Giovanna Fico

Faculty, Staff and Student Publications

Objective: Despite the availability of approved treatments, a substantial proportion of patients with bipolar disorder experience treatment-resistant bipolar depression (TRBD), characterized by persistent depressive symptoms unresponsive to standard therapies. However, a universally accepted definition of TRBD is lacking. This consensus document, developed by the International Society for Bipolar Disorders (ISBD) Task Force on TRBD, aims to provide a standardized definition of TRBD to facilitate clinical trials, research, and treatment strategies.

Methods: The Task Force employed a literature review, clinical trials analysis, and expert consensus meetings to define TRBD.

Results: TRBD was defined as the failure to achieve a significant and …


The Impact Of Tuition Assistance On Employee Retention: Cybersecurity Employee Perceptions Of National Security Agency’S College Tuition Assistance Program, Marta I. Benitez-Guzman Aug 2025

The Impact Of Tuition Assistance On Employee Retention: Cybersecurity Employee Perceptions Of National Security Agency’S College Tuition Assistance Program, Marta I. Benitez-Guzman

Walden Dissertations and Doctoral Studies

U.S. employers spend considerable sums on employee skill development, including investments in college tuition assistance programs (CTAP). Based on a review of recent literature, measuring employer return on investment can be difficult. The literature contained varying results on the effectiveness of employer-provided incentives on retention decisions and provided insufficient empirical or evaluative data on employee perceptions and the influence on retention. The purpose of this qualitative evaluative case study was to examine how cybersecurity employees at the National Security Agency (NSA) who participated in CTAP (2019–2023) perceived the program's effect on their career development and retention decisions. The theoretical framework …


The Association Between Sunlight Exposure Duration, Region Of Birth And Skin Conditions Linked To Skin Cancer Risk Among Migrant Hispanic Farmworkers, Uchechukwu Fidelia Nnoruka Aug 2025

The Association Between Sunlight Exposure Duration, Region Of Birth And Skin Conditions Linked To Skin Cancer Risk Among Migrant Hispanic Farmworkers, Uchechukwu Fidelia Nnoruka

Walden Dissertations and Doctoral Studies

Prolonged exposure to sunlight increases the risk of developing skin conditions linked to skin cancer. Migrant Hispanic farmworkers are especially at risk due to extended outdoor labor, limited access to preventive care, and minimal occupational protections. The purpose of this quantitative study was to examine the association between sun exposure duration and region of birth with the presence of skin conditions associated with skin cancer among migrant Hispanic farmworkers in the United States. This study was grounded by the Social Ecological Model, which provided a comprehensive framework for examining multilevel factors influencing skin health outcomes. Using a cross-sectional design, secondary …


Servant Leadership’S Influence On Job Satisfaction And Personal Well-Being Of Teleworking Employees, Michael Cottam Aug 2025

Servant Leadership’S Influence On Job Satisfaction And Personal Well-Being Of Teleworking Employees, Michael Cottam

Walden Dissertations and Doctoral Studies

Employees who suffer from telework often experience physical and psychological isolation, anxiety, loss of sleep, stressors, and burnout. The availability of digital spaces with advancements in information and communication technologies has created a trend of accepting teleworking in many job functions and industries. Managing these digital teams following the enhanced deployment of telework during the years affected by COVID-19 is a primary concern to prevent poor working conditions and deteriorating mental health for teleworking employees. The purpose of this quantitative correlational study was to examine the relationship between servant leadership and job satisfaction and personal well-being of teleworking employees in …


Lived Experiences Of Newly Graduated Social Workers Transitioning Into The Field Of Child Protective Services, Chantrese Oliver Aug 2025

Lived Experiences Of Newly Graduated Social Workers Transitioning Into The Field Of Child Protective Services, Chantrese Oliver

Walden Dissertations and Doctoral Studies

Lived Experiences of Newly Graduated Social Workers Transitioning Into the Field of Child Protective Services by Chantrese Oliver MPhil, Walden University, 2024 MS, Walden University, 2014 AA, National Paralegal College, 2012 BS, Fayetteville State University, 2010 Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Psychology Walden University August 2025


Orbital Maneuvers And Interplanetary Trajectory Design Via Reinforcement Learning, Roberto Cuéllar Rangel Aug 2025

Orbital Maneuvers And Interplanetary Trajectory Design Via Reinforcement Learning, Roberto Cuéllar Rangel

Doctoral Dissertations and Master's Theses

This dissertation investigates the application of reinforcement learning (RL) to the design and optimization of low-thrust spacecraft trajectories, with an emphasis on autonomy, adaptability, and robustness in the presence of system uncertainties and unmodeled perturbations. Classical approaches to low-thrust trajectory design are predominantly grounded in optimal control theory, which relies on the availability of precise dynamical models and often requires problem-specific reformulation and solver tuning. While optimal control methods offer high accuracy under deterministic conditions, their sensitivity to stochastic disturbances and computational limitations in highly nonlinear or uncertain environments pose significant challenges for future autonomous space missions.

To address these …


Exploring Knowledge, Attitudes, And Practices Of Healthcare Providers In Addressing The Care Needs Of Individuals Who Identify As Lgbtqia+ : A Mixed-Method Study, Seda Karakaya Çataldaş, J. Anneke Rummens, Erin Ziegler, Fahriye Olfaz, Esra Ummak, C. Hürrem Ayhan Aug 2025

Exploring Knowledge, Attitudes, And Practices Of Healthcare Providers In Addressing The Care Needs Of Individuals Who Identify As Lgbtqia+ : A Mixed-Method Study, Seda Karakaya Çataldaş, J. Anneke Rummens, Erin Ziegler, Fahriye Olfaz, Esra Ummak, C. Hürrem Ayhan

Sigma Foundation for Nursing Research Grant Reports

This mixed-methodological study explores the knowledge, attitudes, and practices of healthcare providers (HCPs) and also gathers and analyzes their narrative experiences addressing the care needs of individuals who self-identify as LGBTQIA+. A s ociodemographic form, Knowledge and Practices to Address the Care Needs of LGBTQIA+ Individual Survey, and the Implicit Association T est ( Sexuality IAT and Transpictures IAT) were used as to collect quantitative data from 278 nurses and physicians. S emi-structured in-depth interviews were then held with 15 of these study participants.Quantitative findings revealed slight implicit attitudes favoring heterosexual and cisgender individuals, with education level and personal connections …


Bclaf1 Is A Novel Regulator Of Hematopoietic Stem Cells, Stephanie Crowley Aug 2025

Bclaf1 Is A Novel Regulator Of Hematopoietic Stem Cells, Stephanie Crowley

Arts & Sciences Graduate Student Theses and Dissertations

Hematopoietic stem cells (HSC) maintain both a self-renewal capacity to persist throughout life and an ability to differentiate into mature cell lineages. HSC self-renewal programs are often ectopically activated in leukemia cells to sustain developmental arrest and neoplastic proliferation. Recently, the transcriptional regulator Bclaf1 (Bcl2 associated transcription factor 1) was shown to support proliferation and block differentiation of AML blasts. Bclaf1 is ubiquitously expressed in hematopoietic cells but its function in normal hematopoiesis has not been elucidated. Our data demonstrate that BCLAF1 promotes HSC development and function. To study the role of BCLAF1 in normal HSCs, we used murine models …


The Role Of The Poly-N Repeat In The Plasmodium Falciparum Histone Acetyltransferase Protein, Pfgcn5, Kely Johana Rubiano Cardona Aug 2025

The Role Of The Poly-N Repeat In The Plasmodium Falciparum Histone Acetyltransferase Protein, Pfgcn5, Kely Johana Rubiano Cardona

Arts & Sciences Graduate Student Theses and Dissertations

P. falciparum possesses the most AT-rich genome sequenced to date, with long AAT repeats coding for asparagines (N) in intragenic regions. As a result, nearly a quarter of its proteome is composed of proteins with poly-N repeats. Since the discovery of its genome, the function of these repeats has remained as one of the biggest mysteries in the biology of this parasite. Furthermore, it has long been known that proteins with N-rich domains aggregate easily, particularly during heat stress (HS). Given that the hallmark of this disease is recurrent febrile episodes, it is not well understood how the parasite survives …


Towards A Modular Compliant Actuator Toolkit, Oliver Smith, Swen E. Gaudl, Pablo Borja Aug 2025

Towards A Modular Compliant Actuator Toolkit, Oliver Smith, Swen E. Gaudl, Pablo Borja

School of Engineering, Computing and Mathematics

Compliant Actuators differ from traditional Servo Actuators via the ability to sense and control for forces, in addition to position and velocity. A multitude of concepts exist: force-torque control of brushless DC motors, Series Elastic Actuators (SEAs) featuring a physical elastic element, and Variable Stiffness Actuators (VSA), which use a stiffness control mechanism to modulate the physical stiffness of the elastic element. However, due to the complexity, variety, and prohibitive cost of parts and fabrication, there is a lack of reproduction, which hinders the, development, adoption, and application of such devices. This paper introduces the concept of a Modular Compliant …


Vitamin D Deficiency And Its Role In Pathologies Of Oxidative Stress: A Literature Review, Philippe Dentino, Johanna Mora, Li Zuo Aug 2025

Vitamin D Deficiency And Its Role In Pathologies Of Oxidative Stress: A Literature Review, Philippe Dentino, Johanna Mora, Li Zuo

School of Medicine Publications

Vitamin D (VD) is a key mineral providing critical modulation of reduction-oxidation homeostasis within biological systems. VD and the VD receptor coordinate essential cellular activities, including mitochondrial electron transport, respiration, antioxidation, gene regulation, and calcium transportation. Reactive oxygen species (ROS), a natural by-product of cellular metabolism, play a prominent role in the mechanisms of biological antioxidant systems and form the basis of antioxidant therapies. However, ROS may also perpetuate pathological processes when produced in excess secondary to inflammatory pathways. Aging processes within cells rely on this reduction-oxidation homeostasis. Thus, the interaction with VD, its receptor, mitochondria, and oxidative stress forms …


Defining Treatment-Resistant Bipolar Depression: Recommendations From The Isbd Task Force, Eduard Vieta, Roger S Mcintyre, Trisha Suppes, Tamsyn E Van Rheenen, Balwinder Singh, Kamilla Woznica Miskowiak, Allan H Young, Lakshmi N Yatham, Kyooseob Ha, Michael Berk, Holly A Swartz, Chantal Henry, Maja Pantovic Stefanovic, Gerard Anmella Diaz, Aysegul Ozerdem, Wiesław J Cubała, Diego Hidalgo-Mazzei, Mauricio Tohen, Isabella Pacchiarotti, Paula Villela Nunes, Carlos Lopez-Jaramillo, Ana Gonzalez-Pinto, Paolo Brambilla, Robert Post, Jair C Soares, Michael Bauer, Ana C Andreazza, Xavier Justes Fradera, Montserrat Cosials-Lopez, Giovanna Fico Aug 2025

Defining Treatment-Resistant Bipolar Depression: Recommendations From The Isbd Task Force, Eduard Vieta, Roger S Mcintyre, Trisha Suppes, Tamsyn E Van Rheenen, Balwinder Singh, Kamilla Woznica Miskowiak, Allan H Young, Lakshmi N Yatham, Kyooseob Ha, Michael Berk, Holly A Swartz, Chantal Henry, Maja Pantovic Stefanovic, Gerard Anmella Diaz, Aysegul Ozerdem, Wiesław J Cubała, Diego Hidalgo-Mazzei, Mauricio Tohen, Isabella Pacchiarotti, Paula Villela Nunes, Carlos Lopez-Jaramillo, Ana Gonzalez-Pinto, Paolo Brambilla, Robert Post, Jair C Soares, Michael Bauer, Ana C Andreazza, Xavier Justes Fradera, Montserrat Cosials-Lopez, Giovanna Fico

Faculty, Staff and Student Publications

Objective: Despite the availability of approved treatments, a substantial proportion of patients with bipolar disorder experience treatment-resistant bipolar depression (TRBD), characterized by persistent depressive symptoms unresponsive to standard therapies. However, a universally accepted definition of TRBD is lacking. This consensus document, developed by the International Society for Bipolar Disorders (ISBD) Task Force on TRBD, aims to provide a standardized definition of TRBD to facilitate clinical trials, research, and treatment strategies.

Methods: The Task Force employed a literature review, clinical trials analysis, and expert consensus meetings to define TRBD.

Results: TRBD was defined as the failure to achieve a significant and …


Effect Of High Solar Activity On The Orbital Decay Rate Of The 3u Cubesat Dora, Joseph Dubois, Daniel Jacobs, Siddharth Vaidyanathan Aug 2025

Effect Of High Solar Activity On The Orbital Decay Rate Of The 3u Cubesat Dora, Joseph Dubois, Daniel Jacobs, Siddharth Vaidyanathan

Small Satellite Conference

CubeSats developed at universities seldom have propulsion due to cost and complexity constraints and are very commonly deployed from the ISS into orbits where atmospheric drag is significant. Without propulsion, the time to re-entry is a function of the cross section to mass ratio and the space weather. Many cubesats have limited ways of decreasing ram cross section, e.g. pointing into the wind. Hard radiation from solar activity inflates the atmosphere and increases drag. Since the beginning of the cubesat era, the Sun has been unusually quiescent, at a level not seen for 200 years, which has biased expectations for …


Mission Highlights From Deep Purple And The Pathfinder Technology Demonstrator-R, Lance Simms, Jordan Smilo, Frank Ravizza, Waswa Peter, Wim De Vries, Brian Bauman, John Ganino, Ben Bahney, Kyle Kung, Brendan Smith, Shawn Joseph, Luis Andrade, Declan King, Emily Milne, Christopher Laurent, David Mayer, Jan Stupl, Roger Hunter, John Hanson Aug 2025

Mission Highlights From Deep Purple And The Pathfinder Technology Demonstrator-R, Lance Simms, Jordan Smilo, Frank Ravizza, Waswa Peter, Wim De Vries, Brian Bauman, John Ganino, Ben Bahney, Kyle Kung, Brendan Smith, Shawn Joseph, Luis Andrade, Declan King, Emily Milne, Christopher Laurent, David Mayer, Jan Stupl, Roger Hunter, John Hanson

Small Satellite Conference

Deep Purple is a satellite payload equipped with co-boresighted Ultraviolet (UV) and Short-Wave Infrared (SWIR) telescopes. The payload is hosted on the 6U Pathfinder Technology Demonstrator-R (PTD-R) CubeSat. PTD-R launched on August 16, 2024, into a Sun-synchronous orbit with an altitude of 520km. After successfully exercising basic inertial and Earth-based imaging with Deep Purple, more sophisticated modes that involve tracking Resident Space Objects (RSOs) were demonstrated. This paper highlights the unique sensing capabilities of PTD-R and outlines some of the mission successes achieved over its 10-month campaign. The latter include follow-on imaging campaigns coordinated with LLNL’s other on-orbit SDA demonstration …


Veery, A Flat Satellite Scatterometer For Global, Hourly Refresh Of Ocean Surface Vector Winds, M. Patrick Walton, Alex R. Laraway, David G. Long Aug 2025

Veery, A Flat Satellite Scatterometer For Global, Hourly Refresh Of Ocean Surface Vector Winds, M. Patrick Walton, Alex R. Laraway, David G. Long

Small Satellite Conference

Care Weather is developing Veery, a small satellite scatterometer for monitoring ocean surface vector wind (OSVW) with state-of-the-art performance. Veery uses a rotating fan-beam C-band radar to provide a 1,050 km swath with 25 km resolution and more than 70% uptime. Veery’s dynamic range covers 3–27 m/s with speed errors below 1.6 m/s and directional errors below 11°, matching the performance of previous scatterometers from a much smaller satellite. Veery’s small size is enabled by a flat satellite form factor that vertically integrates the instrument and bus. That small size makes it affordable for deployment in a constellation …


Innocube – First In-Orbit Results Of The Fully Wireless Satellite Data Bus, Tom Baumann, Erik Dilger, Sergio Montenegro, Felix Sittner, Moritz Arbab, Thomas Walter Aug 2025

Innocube – First In-Orbit Results Of The Fully Wireless Satellite Data Bus, Tom Baumann, Erik Dilger, Sergio Montenegro, Felix Sittner, Moritz Arbab, Thomas Walter

Small Satellite Conference

The Innovative CubeSat for Education (InnoCube) mission is a technology demonstration CubeSat that relies entirely on a wireless data bus for intra satellite communication. It was launched in January 2025 onboard SpaceX Transporter-12. This paper presents the mission objectives and initial results, with a particular focus on the performance and reliability of the wireless system.

InnoCube is a collaborative project between the University of Wuerzburg and Technische Universität Berlin in Germany. Its primary objectives are to demonstrate the feasibility of a fully wireless data bus for intra-satellite communication, provide a testbed for new technologies, and offer students hands-on experience in …


The Auroral X-Ray Imager (Axis), Andrew Holland, Karen Holland, David Colebrook, Thomas Buggey, Chiaki Crews, Michael Hubbard, Colin Forsyth, William Dunn, Shyama Narendranath, Srikar Tadepalli, Anurag Tyagi, Koushal Vadodariya, Douglas Jordan Aug 2025

The Auroral X-Ray Imager (Axis), Andrew Holland, Karen Holland, David Colebrook, Thomas Buggey, Chiaki Crews, Michael Hubbard, Colin Forsyth, William Dunn, Shyama Narendranath, Srikar Tadepalli, Anurag Tyagi, Koushal Vadodariya, Douglas Jordan

Small Satellite Conference

The interaction of the solar wind with the Earth is a subject of significant study. One phenomenon is the occurrence of aurorae at the polar regions, resulting from the interaction of particles in the solar wind with the atmosphere, often giving light shows which captures the publics’ imagination. These energetic interactions also extend to X-ray wavelengths. Whilst aurorae have been studied for generations in the visible, the X-ray emission of aurorae has only been observed by a couple of spacecraft, with a paucity of data. There are only a couple of instances of emission intensity having been measured, but without …


Ninjasat Achievements And Lessons Learned, Toru Tamagawa, Takao Kitaguchi, Yo Kato, Tatehiro Mihara, Kentaro Taniguchi, Teruaki Enoto, Tomoshi Takeda, Hiromitsu Takahashi, Naoyuki Ota, Amira Aoyama, Satoko Iwata, Takuya Takahashi, Kaede Yamasaki, Yousuke Nakano, Soma Tsuchiya, Yuto Yoshida, Syoki Hayashi, Sota Watanabe, Arata Jujo, Yuanhui Zhou, Keisuke Uchiyama, Wataru Iwakiri, Mayu Ichibakase, Masaki Numazawa, Hiroki Sato, Chin-Ping Hu, Hirokazu Odaka, Tsubasa Tamba Aug 2025

Ninjasat Achievements And Lessons Learned, Toru Tamagawa, Takao Kitaguchi, Yo Kato, Tatehiro Mihara, Kentaro Taniguchi, Teruaki Enoto, Tomoshi Takeda, Hiromitsu Takahashi, Naoyuki Ota, Amira Aoyama, Satoko Iwata, Takuya Takahashi, Kaede Yamasaki, Yousuke Nakano, Soma Tsuchiya, Yuto Yoshida, Syoki Hayashi, Sota Watanabe, Arata Jujo, Yuanhui Zhou, Keisuke Uchiyama, Wataru Iwakiri, Mayu Ichibakase, Masaki Numazawa, Hiroki Sato, Chin-Ping Hu, Hirokazu Odaka, Tsubasa Tamba

Small Satellite Conference

NinjaSat is a 6U CubeSat dedicated to X-ray astrophysics, launched on November 11, 2023. Scientific observations began on February 23, 2024, and as of June 27, 30 X-ray sources have been observed, yielding numerous scientific outputs. Beyond its primary mission of astronomical observations, NinjaSat has contributed to additional fields, including X-ray pulsar-based navigation, atmospheric studies using X-rays passing through Earth’s limb, investigations of atmospheric structure through orbital decay analysis, and studies of the relationship between the orbital radiation environment and solar activity. By expanding beyond its initial astronomical focus, NinjaSat has demonstrated the versatile potential of scientific CubeSats. This paper …


Climate - Commercial And Scientific Instrument Opportunities For Small Satellite Constellations, Alex Da Silva Curiel, Rob Elliott, Tony Canas, Stephanie Mottershead, Andy Palfreyman, Martin Sweeting Sir Aug 2025

Climate - Commercial And Scientific Instrument Opportunities For Small Satellite Constellations, Alex Da Silva Curiel, Rob Elliott, Tony Canas, Stephanie Mottershead, Andy Palfreyman, Martin Sweeting Sir

Small Satellite Conference

There is an economic and social impact in many areas in the world due to lack of information on local climate, and better understanding is widely believed to lead to cost savings and improved living standards. Despite the wealth of spacecraft data available today, many climate variables are still poorly monitored. Small satellites in constellation can help in filling data gaps, and also provides the important temporal resolution required. Such missions could be highly complementary to the NASA NEO and EU Copernicus programs, and their data can be commercially valuable, opening up the potential for novel business models and services. …


Launch Fast Learn Fast: Lessons Learned From The R5-S2 And R5-S4 Missions, James Berck, Sam Pedrotty, Jack Wisbiski, Morgan Alexander, Kathryn Knesek, Ruth May, Jacob Nunez-Kearny, Rob Stoddard, Thomas Kirven, Robin Onsay, Roger Hunter Aug 2025

Launch Fast Learn Fast: Lessons Learned From The R5-S2 And R5-S4 Missions, James Berck, Sam Pedrotty, Jack Wisbiski, Morgan Alexander, Kathryn Knesek, Ruth May, Jacob Nunez-Kearny, Rob Stoddard, Thomas Kirven, Robin Onsay, Roger Hunter

Small Satellite Conference

The Realizing Rapid, Reduced-cost high-Risk Research (R5) project is pushing the envelope on minimizing cost and schedule for complex spacecraft that support low Technology Readiness Level payload demonstration in Low Earth Orbit (LEO). R5 has recently designed, built, launched, and operated multiple spacecraft that are iteratively and incrementally delivering improved payload hosting capabilities while maintaining cost targets (< $100k in materials per bus) and schedule targets (launching at least two spacecraft per year). This paper will describe the unique architecture, approach, technological advancements, and lessons learned from the project. The primary stakeholder for R5 is the Small Spacecraft Technology program within the Space Technology Mission Directorate at NASA with the project based out of Johnson Space Center.

To achieve the aggressive cost and schedule targets, R5 is redefining the understanding of how much rigor, quality, and robustness are required to succeed in high-risk LEO missions. Starting with a clean-slate for process and system design, R5 has charted a path, …


Expanding Cubesat Horizons: A 27u Mission To Sun-Earth L5, Tabitha Patrick, Allen Martinez, Aimee Dew, Shane Hancock, Michael Generale Aug 2025

Expanding Cubesat Horizons: A 27u Mission To Sun-Earth L5, Tabitha Patrick, Allen Martinez, Aimee Dew, Shane Hancock, Michael Generale

Small Satellite Conference

CubeSats have gained increasing popularity in the aerospace industry due to their compact, modular designs, which offer a cost-effective and versatile solution for orbital applications. Historically limited to low Earth orbit (LEO) due to propulsion and communication constraints, CubeSats are now being explored for deeper space missions. The Icarus mission seeks to demonstrate that a 27U CubeSat can operate at the Sun–Earth Lagrange Point 5 (L5), leveraging recent advancements in efficient electric propulsion and deployable subsystems to monitor solar activity and relay data back to Earth. By capitalizing on a standardized CubeSat form factor with commercial off-the-shelf components, Icarus offers …


Debrisfind: A Cubesat Mission For Evaluating Space Debris Flux In Low Earth Orbit, Ishriak Ahmed, Imraan A. Faruque Aug 2025

Debrisfind: A Cubesat Mission For Evaluating Space Debris Flux In Low Earth Orbit, Ishriak Ahmed, Imraan A. Faruque

Small Satellite Conference

Proliferation in low earth orbits, both operational satellites and defunct or debris items, poses a significant challenge to the long-term sustainability of space operations, and the difficulties in tracking and measuring mm-scale has increased the uncertainty of contemporary statistical models like the NASA Orbital Debris Engineering Model (ORDEM) and ESA MASTER and their statistical debris flux predictions. This uncertainty both complicates orbital mission risk assessment and impedes remediation efforts. This paper develops a CubeSat mission that informs these statistical models through in situ flux determination, providing a comparison of debris flux levels in Low Earth Orbit (LEO). The optimum orbit …


Development Of Model Predictive Control Approach For Precise De-Orbit Of Nanosatellite Using Aerodynamic Drag, Tian Xie, Takashige Suzuki, Maximilien Berthet Aug 2025

Development Of Model Predictive Control Approach For Precise De-Orbit Of Nanosatellite Using Aerodynamic Drag, Tian Xie, Takashige Suzuki, Maximilien Berthet

Small Satellite Conference

Small satellite missions in low Earth orbit (LEO) can utilize propellant-free aerodynamic drag for maneuvering, but achieving precise orbit control is challenged by non-linearities and uncertainties. This paper proposes a nonlinear model predictive control (NMPC) framework designed for precise trajectory tracking under these conditions. By focusing on following a given reference path, our NMPC controller overcomes time-varying perturbations (e.g., J2, J3, J4 effects). We validated this tracking-focused approach with simulations incorporating stochastic atmospheric models. Monte Carlo analysis, using controlled de-orbiting profiles as reference trajectories, demonstrates that our NMPC system provides a powerful tool for enabling precise, propellant-free maneuvers. This work …


Review Of Microgravity Biotechnology For Space Applications: The Anujiva Perspective, Saranya Ravva, Yukti Makkar, Abeneth Ramachandran, Sai Kiran Parre Aug 2025

Review Of Microgravity Biotechnology For Space Applications: The Anujiva Perspective, Saranya Ravva, Yukti Makkar, Abeneth Ramachandran, Sai Kiran Parre

Small Satellite Conference

Biomanufacturing in microgravity presents transformative opportunities for biotechnology beyond the limitations of terrestrial environments. Gravity-driven convection, sedimentation, and contamination risks often hinder biological productivity on Earth. In contrast, space-based conditions enhance protein crystallization, three-dimensional cell culture, and the production of novel biomaterials. This review synthesizes recent advancements in microgravity-enabled biotechnology, drawing from recent peer-reviewed literature and mission data.

We focus on the emerging field of autonomous bioreactor systems for space applications, emphasizing innovations in miniaturization, closed-loop environmental control, and real-time sensing. As a representative case study, we examine the AnuJIVA initiative, a CubeSat-based platform engineered for cultivating microorganisms such as …


High Resolution, Wide Swath Sar Observation From Disksat At Vleo, Hirobumi Saito, Yasuyuki Miyazaki, Michio Takikawa, Tien M. Nguyen, Roy Nakagawa, Ching-Yao (Tony) Chang, David Hinkley, Ryo Natsuaki, Mitsuteru Kaneoka, Jiro Hirokawa, Kazuyuki Nakamura Aug 2025

High Resolution, Wide Swath Sar Observation From Disksat At Vleo, Hirobumi Saito, Yasuyuki Miyazaki, Michio Takikawa, Tien M. Nguyen, Roy Nakagawa, Ching-Yao (Tony) Chang, David Hinkley, Ryo Natsuaki, Mitsuteru Kaneoka, Jiro Hirokawa, Kazuyuki Nakamura

Small Satellite Conference

This paper proposes a novel concept of quasi-two-dimensional SAR (synthetic aperture radar) satellites, SAR DiskSats, featuring a deployable passive slot array antenna (De-PSAA) that can be compactly folded within the quasi-two-dimensional (Q-2D) satellite body. This Q-2D configuration allows for potential flexible solar cell sheets to be installed on the backside of the antenna, as the antennas do not dissipate heat. This satellite configuration is also suitable for stacking within a rocket fairing for the mega-constellation launch of SAR DiskSats into VLEO (very low Earth orbit). The proposed DiskSat's thin edge cross-section reduces aerodynamic drag, enabling the satellite to operate at …


Kentucky Re-Entry Probe Experiment-3: The Third Hypersonic Flight Of The Krups Capsules, Bruno Tacchi, Eric T. Adams, Alexander R. Barrera, Asa C. O'Neal, Aaron Cramer, James E. Lumpp, Savio J. Poovathingal, Alexandre Martin Aug 2025

Kentucky Re-Entry Probe Experiment-3: The Third Hypersonic Flight Of The Krups Capsules, Bruno Tacchi, Eric T. Adams, Alexander R. Barrera, Asa C. O'Neal, Aaron Cramer, James E. Lumpp, Savio J. Poovathingal, Alexandre Martin

Small Satellite Conference

The Kentucky Re-entry Universal Payload System (KRUPS) is a small flight capsule with dimensions of 11 by 8.5 inches and a sphere-cone geometry. KRUPS aims to serve as a cost-effective testbed for hypersonic atmospheric entry experiments, collecting thermal response and flight data during re-entry and testing novel thermal protection systems (TPS). The forebody of the capsule is fitted with an instrumented TPS containing thermocouples and pressure ports. Furthermore, the instrumentation suite contains a high-g accelerometer, a GPS, an IMU, and a spectrometer.

The KRUPS project started in 2013. Since then, the capsule has flown five sounding rocket missions, a high-altitude …


Astra – Autonomous Satellite Technology For Resilient Applications: A Technology Demonstrator, Lauren Underwood, Fernando Figueroa, Zachary Lewton, Landon Tynes, Travis Martin, Jonathan Morris, Quentin Oswald, John Curry Aug 2025

Astra – Autonomous Satellite Technology For Resilient Applications: A Technology Demonstrator, Lauren Underwood, Fernando Figueroa, Zachary Lewton, Landon Tynes, Travis Martin, Jonathan Morris, Quentin Oswald, John Curry

Small Satellite Conference

ASTRA is an on-orbit technology demonstrator establishing a new paradigm for implementing on-board “thinking.” ASTRA is a system-level autonomy capability (including digital twins, anomaly detection, diagnostics/prognostics, and mission management) enabled by an innovative technology, NPAS - NASA Platform for Autonomous Systems. NPAS is developed by NASA Stennis Space Center (SSC) Autonomous Systems Laboratory (ASL) with support from NASA Exploration Systems Development Mission Directorate (ESDMD) Advanced Exploration Systems and Mars Campaign Office. ASTRA leverages NPAS for on-board “thinking” autonomy. ASTRA also includes advanced hardware required for implementing autonomy. ASTRA Flight Software (FS) is running on commercial hardware that provides the computational …


Advancing Space Weather Research With The Next-Generation Space Weather Probes, Justin Wellington, Rowan Antonuccio, Kade Howes, Benjamin Lewis, Todd Wilson, Charles Swenson Aug 2025

Advancing Space Weather Research With The Next-Generation Space Weather Probes, Justin Wellington, Rowan Antonuccio, Kade Howes, Benjamin Lewis, Todd Wilson, Charles Swenson

Small Satellite Conference

Accurate characterization of ionospheric conditions is essential for improving space weather forecasting and mitigating its impacts on communication, navigation, and space-based systems. Utah State University’s Center for Space Engineering has developed the second-generation Space Weather Probes (SWP2) instrumentation suite, optimized for deployment on small satellite platforms. Building upon experience from the Scintillation Prediction Observations Research Task (SPORT) mission, SWP2 integrates advanced Langmuir probes, floating potential double probes, and an RF impedance probe onto a compact, FPGA-controlled electronics module, conforming to the standard 9×9 cm CubeSat form factor. The design provides complementary diagnostic measurements of electron density, electron temperature, electric fields, …