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| University of California San Diego |
| 2011 |
| Modeling Intracranial Pressure in Actual Microgravity |
| The cephalic fluid shift experienced by humans in microgravity has caused numerous headaches for both the humans who have traveled into space and for the scientists trying to understand the mechanisms involved, particularly in regard to the effects on intracranial pressure (ICP). Current understanding suggests all astronauts are at risk of elevated pressures and swelling in the eyes as a probable result of intracranial hypertension and some degree of anatomical susceptibility,which can result in permanent vision impairment. Despite the numerous health challenges associated with fluid shifts in microgravity, all of the physiological mechanisms responsible are not completely understood. 6º head down tilt (HDT) is used as a bedrest analog to long-duration spaceflight, but the effects on intracranial pressure are not as marked. The difficulty of noninvasive measurement and small number of research opportunities presents challenges to understanding the dynamic circulatory changes that occur in reduced gravity, and their effect on ICP. Additionally, the flow characteristics of viscoelastic fluids (e.g. blood) through collapsible tubes (e.g veins) are unintuitive. For these reasons we propose to construct a model that will represent major features, pressures and flows of the cephalic and cranial circulation, and to empirically test fluid shift and ICP hypotheses in microgravity aboard a parabolic flight. Results will be compared to the same experiment performed in 1G standing upright, supine, and in 6º head down tilt (HDT). Additional angles will also be tested so that post-flight we can determine, based on the model, what angle of head down tilt best reproduces the intracranial pressures measured in microgravity. Between flights, "brain tissue" volume will be decreased to correspond to the average age-related atrophy expected between the youngest astronaut to ever fly, Sally Ride (32), and the oldest, John Glenn (77), which we expect to see as protective. |
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| Austin Community College |
| 2011 |
| Environmental Impacts on the Locomotion of Drosophila Melanogaster |
| Drosophila locomotion is an evolving subject of research. Results are only comparable in the terms by which they were measured, which until as of late was varied. With the aid of video recording and mathematical algorithms capable of quantitatively processing fly position, research has begun to move forward with an objective standard of measure. Using the latest protocols for 3-dimensional motion tracking our team will capture the flight patterns of wild-type Drosophila Melanogaster in microgravity and statistically compare data from normal gravity with that recorded in microgravity. |
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| Boise State University |
| 2011 |
| Fluorescent Monitoring of Parabolic FlightInduced Calcium Flux in Osteocyte Osteoblast Co-cultures |
| Bone homeostasis is a dynamic phenomena in which environmental stress information is continually translated into remodeling responses by specialized sensory and effector cell populations. Under normal conditions this remodeling process promotes optimal distribution of mineralized matrix to meet biomechanical requirements. Under extreme conditions the remodeling balance can shift toward excessive resorption or mineralization, as evidenced by prolonged exposure to microgravity leading to bone loss in astronauts. In order to prevent and treat bone pathologies resulting from imbalanced remodeling it is crucial to identify the regulatory mechanisms that allow sensory cells to integrate varied and often contrasting mechanical stimuli into committed effector responses. A current model proposes that the biochemical pathways orchestrating remodeling act in simple opposition to opposing stimuli, however evidence exists that suggests a capacity for more complex regulative behavior. Parabolic flight provides an ideal environment to examine the intersection of opposing stimuli in the form of hyper and microgravity. Co-cultures of sensor (osteocyte) and effector (osteoblast) cells will be exposed to oscillating gravitational conditions and the activity of calcium, an early mediator of mechanosensitive responses, will be monitored. If calcium responses are shown to vary over the course of cycles between hyper and microgravity rather than to respond in simple and consistent opposition, mechanisms related to calcium flux will be implicated as potential points of regulation. |
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| California Institute of Technology |
| 2011 |
| Development and Analysis of Light-Weight Self-Deployable Carbon Fiber Composite Space Structures |
| The proposed experiment aims to quantitatively investigate how various parameters affect the deployment of thin-walled carbon fiber hinges. These hinges have been used as joints for a variety of space based applications over the past decade from solar arrays to spacecraft antenna; however their deployment characteristics are not fully understood. The lack of information about the deployment characteristics of these joints has led to long delays in past missions where the numerical simulations ineffectively predicted joint behavior. The goal of the proposed experiment is to compare deployment characteristics of the carbon fiber joints in microgravity to prior numerical simulations and simulated microgravity experiments in order to improve the numerical models of prior research. Refining these models will lead to better prediction algorithms for how a joint will deploy in microgravity, and open up the possibility of widespread implementation of carbon fiber hinges on space structures. |
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| California Polytechnic University |
| 2011 |
| Adaptive Control Experiment (ACE) |
| Satellites in orbit are subject to a demanding environment in which their mass properties can change unexpectedly. Currently, the attitude adjustment of most spacecraft is dependent on known values for the mass properties of the system. When the mass properties of a system change, the control dynamics of that system are altered. In addition, mechanical systems used to adjust attitude, such as reaction wheels, can degrade over time -often without detection. Both can potentially lead to system malfunctions. We plan to test an Attitude Control Simulator (ACS) that will implement an adaptive control law to adjust attitude. The ACS will consist of a platform of four reaction wheels and an Inertial Measurement Unit (IMU) coupled with analyzing software. The adaptive controller will adjust to the altered control dynamics of the system even when a reaction wheel is purposely degraded. We plan to prove that an adaptive control system is capable of adjusting attitude when the control dynamics of the system are changed or unknown. Testing the ACS in a microgravity environment is critical to simulating realistic working conditions and will allow us to compare the results to similar tests conducted on the ground. Ultimately, the performance of the ACS using an adaptive controller can be compared to current industry standards. |
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| California State Polytechnic University, Pomona |
| 2011 |
| Experimental Methods in Attitude Control - CubeSat Technology |
| The Aerospace Engineering Department at California State Polytechnic University, Pomona strives to provide real-world applications and solutions for future aerospace industry leaders through innovative projects. The department has recently joined the worldwide effort to improve CubeSat technology. CubeSats are picosatellites used to research various spacecraft applications, such as remote sensors (Malik), tethers (Young), and biological experiments (David; Science Tuesday). Their low-cost and small size makes them perfect for new research and investment, giving these diminutive satellites the potential to revolutionize space operations in commercial industry, educational research, and government projects (David; Tech Wednesday). Current picosatellites mainly rely on magnetic coils or permanent magnets for attitude control, while others lack an attitude control system entirely (Villanueva). A possible solution is the use of commercially manufactured DC motors as actuators for attitude control. Using commercially available off-the-shelf components from the commercial RC hobby industry, it is possible to provide sophisticated attitude control for picosatellites. Standard hobby servomechanisms provide compact, sophisticated, mass-produced technology for an affordable price ("Seattle Robotics"). We propose to continue an existing experiment, where we modified servomechanisms and used a CubeSat standardized platform in microgravity to test for their effectiveness as actuators. Successful flights may demonstrate that the approach proposed presents a technologically sound and inexpensive solution to the problem of picosatellite attitude control using currently available technology. |
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| California State Polytechnic University, Pomona |
| 2011 |
| SEED - Emergency Atmospheric Entry with Control in One Axis |
| SEED - Emergency Atmospheric Entry with Control in One Axis |
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| California State University Fresno |
| 2011 |
| Calcium Oxalate Formation in Microgravity |
| Calcium oxalate is a salt crystal found in many plants and fruits such as spinach, tea, and the kiwifruit. This salt crystal, should it be ingested in excessive amounts can prevent speech as well as induce suffocation. Calcium oxalate is also known as a kidney stone which can cause painful occurrences as it passes from the human kidney through to the urine tract. This chemical compound (calcium oxalate) accounts for 75% of all kidney stones. Lastly, calcium oxalate crystals are caused by the lack of Calcium available to bind the oxalate into a non-absorbable form in the stomach and the intestines, this change causes the oxalate to be absorbed and then excreted through the urine, raising the risk for kidney stones. Our experiments aim to investigate whether gravity has an effect on the formation and production of calcium oxalate crystals. These conclusions will be based off our current preliminary and future experimental samples on whether or not Calcium Oxalate Crystals change their molecular structure when subjected to a lack of the gravitational force. Knowledge gained from this study can aid in preventable actions for kidney stones that may possibly develop in astronauts during prolonged space missions; furthermore, our experimental studies will aid in NASA's current issues with Calcium Oxalate Crystal precipitation and filter clogging in the water waste system aboard the spacecraft. Data collected and analyzed at this stage of our research will be based on gravitational changes and crystal formation. |
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| California State University Fresno |
| 2011 |
| Formation of Calcium Oxalate in a Microgravity Environment |
| The experiments that we are proposing involve the formation of Calcium Oxalate and its effects on the growth of Calcium Oxalate-producing plants in the microgravity environment. A plant's ability to survive depends on its ability to deter predators and meanwhile to attract insects that facilitate pollination and its ability to reproduce. Our experiments aim to investigate whether gravity has an effect on the production of Calcium Oxalate. We will determine whether the formation of Calcium Oxalate has adverse effects on the ion concentration in the vacuoles of a parenchyma cell and whether the displacement of secondary metabolites may form cyto-toxic side effects. In addition, we plan to find whether Calcium Oxalate varies in Nectaries or pollen, since this possible variation could warrant unwanted characteristics for pollinators and beneficial organisms. |
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| Carnegie Mellon University |
| 2011 |
| iMicrogravity - G-jitter measurements using an inexpensive accelerometer network |
| We want to determine the feasibility of using multiple inexpensive accelerometers to construct a stream of acceleration data suitable for measuring g-jitter effects in the microgravity environment. The apparatus will consist of eight Apple iPod touch devices, wirelessly transmitting data to a central computer. The system must be accurate, must synchronize the clocks across all of the devices, and should be able to display the acceleration data in real time. To construct this system, custom software will be written for the devices and for the central computer. If the system is successful, its software will be released to the general public to generate interest in reduced gravity research and for scientific research in general. |
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