48 research outputs found
NASA's CubeQuest Challenge - From Ground Tournaments to Lunar and Deep Space Derby
The First Flight of NASA's Space Launch System will feature 13 CubeSats that will launch into cis-lunar space. Three of these CubeSats are winners of the CubeQuest Challenge, part of NASA's Space Technology Mission Directorate (STMD) Centennial Challenge Program. In order to qualify for launch on EM-1, the winning teams needed to win a series of Ground Tournaments, periodically held since 2015. The final Ground Tournament, GT-4, was held in May 2017, and resulted in the Top 3 selection for the EM-1 launch opportunity. The Challenge now proceeds to the in-space Derbies, where teams must build and test their spacecraft before launch on EM-1. Once in space, they will compete for a variety of Communications and Propulsion-based challenges. This is the first Centennial Challenge to compete in space and is a springboard for future in-space Challenges. In addition, the technologies gained from this challenge will also propel development of deep space CubeSats
Cube Quest Challenge: A Government Prize for Advanced CubeSat Technologies for Affordable Deep Space Science and Exploration Missions
NASA STMD Centennial Challenges Program operates government prize programs for the public benefit. Cube Quest Challenge awards prizes to citizen inventors who advance CubeSat state of the art, enabling affordable NASA science and exploration missions. Cube Quest will take place in lunar orbit or at 4M km. CubeSat developers will make advancements in communications, propulsion and radiation tolerance suitable for future deep space missions. Cube Quest may inspire other ambitious government challenges
NASAs EDSN Aims to Overcome the Operational Challenges of CubeSat Constellations and Demonstrate an Economical Swarm of 8 CubeSats Useful for Space Science Investigations
Operators of a constellation of CubeSats have to confront a number of daunting challenges that can be cost prohibitive, or operationally prohibitive, to missions that could otherwise be enabled by a satellite constellation. Challenges including operations complexity, intersatellite communication, intersatellite navigation, and time sharing tasks between satellites are all complicated by operating with the usual CubeSat size, power, and budget constraints. EDSN pioneers innovative solutions to these problems as they are presented on the nano-scale satellite platform
NASA Centers and Universities Collaborate in Annual Smallsat Technology Partnerships
The Small Spacecraft Technology program within the NASA Space Technology Mission Directorate sponsors the Smallsat Technology Partnerships (STP) initiative. The STP initiative awards cooperative agreements between NASA centers and university teams for technology development efforts that advance the capabilities of small spacecraft to achieve NASA mission objectives in unique and more affordable ways.
NASA’s announcement to return humans to the Moon by 2024 raises new opportunities for Smallsats to contribute to missions in cislunar space, though technical challenges are to be overcome to establish their value in this environment. Precursor missions utilizing small spacecraft will blaze the trail for lunar exploration, establishing infrastructure such as communication and navigation networks, and performing assembly and repair services for larger structures and human habitats. To achieve these goals, certain novel Smallsat technologies will need to be developed and demonstrated. The 2020 STP solicitation sought proposals for specific technologies to enable these lunar missions.
For the 2020 STP cycle, NASA selected nine university teams to mature new systems and capabilities in the laboratory, and in some cases, demonstrate in suborbital or orbital spaceflights. This paper describes the STP portfolio, past and present efforts, and the nine partnerships selected
Culture of equine fibroblast-like synoviocytes on synthetic tissue scaffolds towards meniscal tissue engineering: a preliminary cell-seeding study
Introduction. Tissue engineering is a new methodology for addressing meniscal injury or loss. Synovium may be an ideal source of cells for in vitro meniscal fibrocartilage formation, however, favorable in vitro culture conditions for synovium must be established in order to achieve this goal. The objective of this study was to determine cellularity, cell distribution, and extracellular matrix (ECM) formation of equine fibroblast-like synoviocytes (FLS) cultured on synthetic scaffolds, for potential application in synovium-based meniscal tissue engineering. Scaffolds included open-cell poly-L-lactic acid (OPLA) sponges and polyglycolic acid (PGA) scaffolds cultured in static and dynamic culture conditions, and PGA scaffolds coated in poly-L-lactic (PLLA) in dynamic culture conditions.Materials and Methods. Equine FLS were seeded on OPLA and PGA scaffolds, and cultured in a static environment or in a rotating bioreactor for 12 days. Equine FLS were also seeded on PGA scaffolds coated in 2% or 4% PLLA and cultured in a rotating bioreactor for 14 and 21 days. Three scaffolds from each group were fixed, sectioned and stained with Masson’s Trichrome, Safranin-O, and Hematoxylin and Eosin, and cell numbers and distribution were analyzed using computer image analysis. Three PGA and OPLA scaffolds from each culture condition were also analyzed for extracellular matrix (ECM) production via dimethylmethylene blue (sulfated glycosaminoglycan) assay and hydroxyproline (collagen) assay. PLLA coated PGA scaffolds were analyzed using double stranded DNA quantification as areflection of cellularity and confocal laser microscopy in a fluorescent cell viability assay.Results. The highest cellularity occurred in PGA constructs cultured in a rotating bioreactor, which also had a mean sulfated glycosaminoglycan content of 22.3 µg per scaffold. PGA constructs cultured in static conditions had the lowest cellularity. Cells had difficulty adhering to OPLA and the PLLA coating of PGA scaffolds; cellularity was inversely proportional to the concentration of PLLA used. PLLA coating did not prevent dissolution of the PGA scaffolds. All cell scaffold types and culture conditions produced non-uniform cellular distribution.Discussion/Conclusion. FLS-seeding of PGA scaffolds cultured in a rotating bioreactor resulted in the most optimal cell and matrix characteristics seen in this study. Cells grew only in the pores of the OPLA sponge, and could not adhere to the PLLA coating of PGA scaffold, due to the hydrophobic property of PLA. While PGA culture in a bioreactor produced measureable GAG, no culture technique produced visible collagen. For this reason, and due to the dissolution of PGA scaffolds, the culture conditions and scaffolds described here are not recommended for inducing fibrochondrogenesis in equine FLS for meniscal tissue engineering
CubeSat Active Thermal Control via Microvascular Carbon Fiber Channel Radiator
Small spacecraft rarely have space for any thermal control subsystems and often must perform operations in “burst” mode as a result. The few spacecraft who do have control rely on low-complexity thermal control systems which conduct heat to the bus structure and then radiate the heat away. These simplistic techniques are sufficient for low power missions in Low Earth Orbit (LEO) but are not capable of dumping the heat produced in new mission profiles that are in development. This is due to small spacecraft incorporating increasingly advanced subsystems which have difficult thermal control requirements such as propulsion systems or high-power antennas. The University of Illinois at Urbana-Champaign, in partnership with NASA Ames Research Center, is developing a thermal control system for small spacecraft. This control system uses a deployable radiator panel made from carbon fiber with micro-vascular circulatory system for coolant. This paper is a follow-up on the previous year’s SmallSat conference. A bench prototype of the thermal control subsystem was designed and built. The prototype underwent a range of thermal and vibration tests at NASA Ames. Test results and lessons learned are presented. Moving forward, test conclusions will require some design parameters to be changed and the subsystem will reach TRL 6 by the end of the two-year program
Recommended from our members
Culture of equine fibroblast-like synoviocytes on synthetic tissue scaffolds towards meniscal tissue engineering: a preliminary cell-seeding study
INTRODUCTION: Tissue engineering is a new methodology for addressing meniscal
injury or loss. Synovium may be an ideal source of cells for in vitro meniscal fibrocartilage
formation, however, favorable in vitro culture conditions for synovium must be
established in order to achieve this goal. The objective of this study was to determine
cellularity, cell distribution, and extracellular matrix (ECM) formation of equine
fibroblast-like synoviocytes (FLS) cultured on synthetic scaffolds, for potential application
in synovium-based meniscal tissue engineering. Scaffolds included open-cell
poly-L-lactic acid (OPLA) sponges and polyglycolic acid (PGA) scaffolds cultured
in static and dynamic culture conditions, and PGA scaffolds coated in poly-L-lactic
(PLLA) in dynamic culture conditions.
MATERIALS AND METHODS: Equine FLS were seeded on OPLA and PGA scaffolds, and
cultured in a static environment or in a rotating bioreactor for 12 days. Equine FLS
were also seeded on PGA scaffolds coated in 2% or 4% PLLA and cultured in a
rotating bioreactor for 14 and 21 days. Three scaffolds from each group were fixed,
sectioned and stained with Masson’s Trichrome, Safranin-O, and Hematoxylin and
Eosin, and cell numbers and distribution were analyzed using computer image analysis.
Three PGA and OPLA scaffolds from each culture condition were also analyzed
for extracellular matrix (ECM) production via dimethylmethylene blue (sulfated
glycosaminoglycan) assay and hydroxyproline (collagen) assay. PLLA coated PGA
scaffolds were analyzed using double stranded DNA quantification as a reflection of
cellularity and confocal laser microscopy in a fluorescent cell viability assay.
RESULTS: The highest cellularity occurred in PGA constructs cultured in a rotating
bioreactor, which also had a mean sulfated glycosaminoglycan content of 22.3 ÎĽg per
scaffold. PGA constructs cultured in static conditions had the lowest cellularity. Cells
had difficulty adhering to OPLA and the PLLA coating of PGA scaffolds; cellularity
was inversely proportional to the concentration of PLLA used. PLLA coating did not
prevent dissolution of the PGA scaffolds. All cell scaffold types and culture conditions
produced non-uniformcellular distribution. DISCUSSION/CONCLUSION: FLS-seeding of PGA scaffolds cultured in a rotating bioreactor resulted in the most optimal cell and matrix characteristics seen in this study.
Cells grew only in the pores of the OPLA sponge, and could not adhere to the PLLA
coating of PGA scaffold, due to the hydrophobic property of PLA. While PGA culture
in a bioreactor produced measureable GAG, no culture technique produced
visible collagen. For this reason, and due to the dissolution of PGA scaffolds, the
culture conditions and scaffolds described here are not recommended for inducing
fibrochondrogenesis in equine FLS for meniscal tissue engineering.Keywords: Stifle,
Orthopedics,
Bioreactors,
Fibroblast-like synoviocytes,
Meniscus,
Cell scaffolds,
Tissue engineering,
Bioengineering,
Veterinary Medicine,
Surgery and Surgical Specialties,
EquineThis is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by PeerJ. The published article can be found at: https://peerj.com/
Proteome and Antigen Profiling of Coxiella burnetii Developmental Forms
A biphasic developmental cycle whereby highly resistant small-cell variants (SCVs) are generated from large-cell variants (LCVs) is considered fundamental to the virulence of Coxiella burnetii, the causative agent of human Q fever. In this study a proteome analysis of C. burnetii developmental forms was conducted to provide insight into their unique biological and immunological properties. Silver-stained gels of SCV and LCV lysates separated by two-dimensional (2-D) gel electrophoresis resolved over 675 proteins in both developmental forms. Forty-eight proteins were greater than twofold more abundant in LCVs than in SCVs, with six proteins greater than twofold more abundant in SCVs than in LCVs. Four and 15 upregulated proteins of SCVs and LCVs, respectively, were identified by mass spectrometry, and their predicted functional roles are consistent with a metabolically active LCV and a structurally resistant SCV. One-dimensional and 2-D immunoblots of cell form lysates probed with sera from infected/vaccinated guinea pigs and convalescent-phase serum from human patients who had recovered from acute Q fever, respectively, revealed both unique SCV/LCV antigens and common SCV/LCV antigens that were often differentially synthesized. Antigens recognized during human infection were identified by mass spectroscopy and included both previously described immunodominant proteins of C. burnetii and novel immunogenic proteins that may be important in the pathophysiology of clinical Q fever and/or the induction of protective immunity