A research group at NASA Ames Research Center has opportunities for students to participate in "human-centered computing"; an approach to designing information technologies based on the study of how people work together. These opportunities require no special background, but do require a willingness to use ordinary skills, such as listening, reading, and talking, in new ways.

All group projects are intended to have methodological and practical outcomes. Methodologically, the group is concerned with innovation in qualitative social research data collection, analysis, interpretation and modeling. Video ethnography, for example, is a particular interest. Practically, we attempt to support the work of NASA in, for instance, the study of extraterrestrial life, Mars exploration, and mission control. Possible research areas include the following:

-Laboratory work and the use of microscopes

-Collaboration in extreme environments

-Organizational learning

-New ways of presenting information on the web

-Work practices modeling and simulation

Richard Keller, Code IC

ScienceDesk Project

The ScienceDesk Project is building computational tools to support the daily work activities of scientific teams within the Astrobiology Institute. These include data preparation and manipulation, remote experimentation and monitoring, model-building and execution, and document-sharing. We are particularly focused on building Internet-based tools that make data and information easily accessible from any location and at any stage in the lifecycle of a scientific project -- from proposal thru publication. Our project is currently developing prototypes to support scientific lab work involving electron microscopy, as well as biological field work in early microbial ecosystem studies. Students with strong interest and/or experience in scientific applications of computers, the Internet/World Wide Web, and programming would be good candidates for this position. Exact work would depend on student's skills and the projects needs, and may involve study and observation of working science teams, design and testing of computer tool prototypes, programming, etc.

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Infrared observations combined with realistic laboratory simulations have revolutionized our understanding of interstellar ice and dust, the building blocks of comets. Since comets are thought to be an important source of the organics which seeded the early Earth, it is important to understand the prebiotic chemistry these induced on the primitive Earth. In The Astrochemistry Laboratory, we simulate interstellar and cometary chemistry and have shown that many complex organic species are readily formed from the photochemistry of astrophysically-realistic ice mixtures. Since comets brought these materials into the young Solar System, seeding the early Earth with their complex organic inventory, an important question these results raise is, "Have comets provided important raw materials from which life started on Earth?"

Hexamethylenetetramine (HMT) is one of the more intriguing molecules formed in our comet simulations. HMT has been reported to form amino acids in water solution, and amino acids are considered crucial to life. However, the earlier research on HMT did not study the reaction thoroughly nor did it examine the range of conditions relevant to the conditions on the primitive Earth. A more thorough analysis under plausible prebiotic conditions is necessary to understand whether the cometary input of HMT could have been a critical source of amino acids for the origin of life or merely a minor contributor.

The project we propose is to study the reactions of HMT under a variety of reasonable primitive terrestrial conditions, seeking to fully identify the amino acids produced when HMT is placed in water solutions and to understand the kinetics of various amino acid production routes.

The focus will be primarily on the effect of temperature and pH in simulated early Earth "oceans" in order to extrapolate the results to realistic scenarios of the primitive Earth. The student should have an interest in chemistry, some laboratory experience, and some knowledge of kinetics. Analytical techniques available include fluorescence HPLC, IR and UV/Vis spectroscopy, and possibly NMR. The student will learn to become proficient on these instruments. Thus, this project affords the opportunity for a student to help answer an important astrobiological question as well as improve their understanding of kinetics and gain valuable experience with several sophisticated analytical techniques.

We have new spacecraft-obtained astrophysical data. The observations were recently made using the Hubble Space Telescope (HST) and the Infrared Space Observatory (ISO). The interested student would help with processing/analysis of these data. The observations are of the Orion Nebula - a region where stars are being born - and several planetary nebulae (PNs). PNs are part of the late-in-life evolution of most stars (including the Sun someday). The HST observations are producing spectacular pictures of the PNs for which we have ISO data. Some of the things we are trying to learn about these astronomical objects include what chemical elements are present and in what quantities. By studying young regions like the Orion Nebula and old ones like the PNs, we are able to measure cosmic evolution of the elements. Abundant elements in space are hydrogen, helium, carbon, nitrogen, and oxygen. With the exception of helium, these are also the most interesting/important in terms of the organic chemistry and astrobiology implications. As well as having an interest in the above science, the student should be capable with computers. Familiarity with UNIX will be helpful as we have Sun workstations and also access to the NASA Ames Cray supercomputer for some of the interpretive work. The data processing will involve use of IRAF (Image Reduction and Analysis Facility software package) (please see http://iraf.noao.edu) and advance knowledge, although not required, would certainly be useful.

This project has to do with the propagation of electrical currents through rocks such as basalts, gabbros, and granites which are normally electrical insulators. It has recently been discovered that even nominally anhydrous rocks pick up traces of water while crystallizing in the H2O-laden Earth's crust or mantle. The water is incorporated into mineral structures in form of hydroxyl groups, as Si-OH and Si-OH pairs. During cooling, the SiOH pairs rearrange to form peroxy links, Si/OO\Si and H2 molecules. The peroxy links are interesting in as much as they easily fall apart, turning into an electronic charge, a defect electron or "hole". The rocks then become instantly p-type semiconductors! When this occurs, they display a range of unusual phenomena, which are both fun and a challenge to study. A facinating aspect is that mechanical shock, such as that of an impact, splits the peroxy links and allows the highly mobile holes to flow through the rock. As they flow, they build up electric fields at the rock surface - so high that plasma discharges occur. At the same time strange magnetic effects are observed. These phenomena have a wide range of implications: the positive holes are highly oxidizing, and interact with the environment of the rock. The geophysical aspect comes in trying to understand why rock fracturing can lead to electrical and magnetic phenomena in the ground which can be observed in the atmosphere and even in the ionosphere prior to and during earthquakes. These phenomena have been long reported, but never really understood. The impact-driven electricity and magnetism have also the potential to teach us more about the anomalous magnetic patterns on the moon and Mars, which are observed in the cratered highlands. On Earth, where liquid water causes weathering, the peroxy in the rocks are hydrolyzed to hydrogen peroxide, H₂O₂. The earliest organism would have had to develop a defense to this highly oxidizing agent. The project involves measuring the generation of positive hole charge carriers in, and their propagation through various rocks. Experiments are conducted with low-velocity and medium velocity impacts at the Ames Vertical Gun Range, and fast, real-time data acquisition, determining the propagation, the scattering and the lifetime of the charge carriers in different rocks.

Most meteoric matter accretes on Earth in the form of around 200 micron sized particles causing +8 magnitude meteors. The colliding air molecules sputter the meteoric matter which is released in the form of atoms and small molecules. Organic matter in the meteoroid is lost in the form of C2 and CN, emission lines of which have been detected in meteor spectra.

The summer Research Associate will analyze meteor spectra obtained by a new video imaging technique and search for the C2 and CN bands. Successful detection's are compared to the physical properties of the meteors in order to characterize the conditions in which these molecules are produced. The results will be interpreted in the context of seeding the early Earth with meteoric reduced organic matter, and will prepare for observations of the 1998 and 1999 Leonid meteor storms.

This research centers around some of the earliest reactions involved in the origin of life. Reactions which occurred in the period before the first universal ancestor of modern life appeared but after the Earth had cooled enough to allow liquid water and was no longer being sterilized by large impacts. Specifically, studies address an early Earth with a carbon dioxide and nitrogen atmosphere and consider how the reduced carbon and nitrogen molecules that made up the "prebiotic soup" might have been formed. Research is conducted by postulating what reactions might have caused this to happen, seeing if they will run in the lab under conditions that might have existed back then, measuring how fast the reactions will go, and using kinetic models to determine how important those reactions would have been on the early Earth. Work also has started on examination of extra-terrestrial samples to characterize their organic content by sensitive state-of-the-art techniques.

Use of Mars Wind Tunnel to Quantify Dust Transport on the 2001 Mars Lander

Viking and Pathfinder surface operations have shown that widnblown dust is ubiquitous on Mars and will impact surface operations, including landers, rovers, and human operations. The Mars Wind Tunnel will be used to simulate effects of winds and resultant patterns of dust depositon and erosion on the operations associated with the Mars Surveyor 2001 Lander. The Lander deck will include the following relevant experiments: 1. a panoramic imaging system and emission spectrometer on a mast, with associated radiometric calibration targets on the deck; 2. an experiment called MECA, which will focus on microscopic examination and wet chemistry of soil samples delivered to the experiment by a robotic arm and scoop; and 3. MIP, an experiment which includes solar cells that can be rotated to remove accumulated dust, determination of dust thickness by examining solar transmissive losses, and a dust electrostatic repulsion experiment. Further, patch plates on the deck for MECA and a Moessbauer calibration target will be on the deck. Wind deposited dust and dust deposited onto the deck during delivery of samples to MECA will strongly influence the calibration targets and the MIP experiments. The Pancam and infrared spectrometer will be used to monitor these effects. The intent of this task is to use the Mars Wind Tunnel and scale models of the deck and its instruments to understand the dynamics of dust deposition and erosion under various wind regimes on Mars. The scale models will be supplied by R. E. Arvidson, Washington University, a collaborator on the project. Working with the team, the student will develop and run experiments to simulate effects of dust on the various instruments and experiments on the deck. The student will also derive ramifications for mission operations for 2001 and beyond, including human expeditions.

Background: The Space Station Biological Research Project (SSBRP) is responsible for the development of facilities which will be used to conduct research with animals and plants aboard the International Space Station (ISS). The orbiting laboratory will provide the tools to conduct research on the effects of space (e.g. microgravity and radiation) on reproduction and development, the musculoskeletal system, neurophysiological processes, and genetics. Experiments will be done at the whole-organism, system, cellular, and molecular levels. Features of the Space Station Facilities will include multiple habitats to support a variety of organisms, a centrifuge with a selectable rotation rate to house specimen habitats at a variety of gravity levels, and a fully equipped workstation/glovebox. The habitats include a Cell Culture Unit for cell and tissue cultures, a Plant Research Unit for plants, an Egg Incubator for studies in early development, an Insect Habitat for multigenerational and radiation studies, an Aquatic Habitat for fresh water and marine organisms, and an Advanced Animal Habitat for rats and mice.

Research Activity: In the SSBRP Aquatic Laboratory we are conducting studies to better understand the unique environmental conditions required to maintain aquatic research models in space. We are focusing specifically on the zebrafish, Danio rerio, because of its many important contributions to the areas of developmental biology, neurobiology, and molecular genetics. Experiments aboard the ISS are expected to include exposure to hypergravity conditions utilizing the large 2.8 m Centrifuge Facility. However, it is not known how aquatic research models, such as the zebrafish, will respond to gravity forces greater than 1-g. A gas-filled swimbladder, equivalent to approximately 5-7% of body volume in freshwater, is required by fish to counteract their density (~ 1.06 g/ml) and achieve neutral buoyancy. Fish will need to increase this volume proportionally with increased gravitational forces to maintain neutral buoyancy, normal posture, feeding behavior, and spawning behavior. This study will expose larval and adult zebrafish to hypergravity conditions induced by centrifugation. Behavior will be monitored by video to examine buoyancy changes, posture, feeding behavior, and whether the air-water interface is used for swimbladder volume regulation. Post-exposure analysis will quantify the extent of swimbladder volume. The student will be able to participate in all stages of the study including the design of the experimental system for centrifugation, data collection, statistical analysis, and the preparation of written reports.

Research Goal: Our objective is to quantify changes in swimbladder volume and whole-body buoyancy regulation in zebrafish following exposure to hypergravity conditions and upon return to a 1-g environment. These responses will be used to predict the behavior of experimental fish aboard the ISS and the limits of hypergravity to which they can be exposed.

Adaptation is defined as "modification of an organism or its parts that makes it more fit for existence under conditions of it's environment". Perhaps individual differences in the ability to adapt to microgravity are related to differences in autonomic plasticity. Autonomic neural plasticity is a term that describes the capability of organisms to modify ANS function through learning. Psychophysiology is the study of the relationship between behavior and physiology.

The purpose of this research is to address the NASA requirement for ground-based studies examining vestibular/autonomic interaction as related to adaptation to microgravity and readaptation to Earth. The primary goals of this work are to (i) understand the mechanisms by which behavioral (Autogenic Feedback Training Exercise AFTE - an autonomic conditioning procedure), and pharmacological countermeasures (e.g., scopolamine, promethazine and phenytoin) improve tolerance to motion and space motion sickness, and (ii) determine the treatment method most likely to be effective for facilitating adaptation to microgravity and re-adaptation to Earth with minimal side-effects. Through AFTE it may be possible to learn more about the influence of CNS (or cognitive) activity on other space flight related biomedical problems as well, such as post-flight orthostatic intolerance. This research also uses NASA technology to investigate other environments that induce motion sickness, such as military vehicles. By understanding individual differences in ANS function when exposed to altered gravity and other environments causing motion sickness, we may be better able to develop and evaluate countermeasures needed to facilitate adaptation.

Charles W. DeRoshia

A brief description of recent research projects which are representative of studies I work on follows. A student working with me would work on one of several studies of human preformance.

I have been a co-investigator in several studies of the effects of long-duration weightlessness simulated by bedrest, altered cerebral blood flow induced by head-down tilt, and anti-motion sickness drugs upon human mood and performance. I was also a coninvestigator on studies of the effects of hypergravity on psychophysical cross-modal matching perception and visual-neuromotor error-corrective feedback. I am currently a co-investigator on a study to evaluate cosmonaut mood and performance during a long-duration MIR flight and the effects of motion sickness upon tank crew performance. I am also supporting several ongoing studies of the effects of altered body orientation and retinal image pitch on oculomotor responses and perception of the zenith and the effects of altered gravity on the psychophysical function.

Long term exposure to a zero-G environment causes many physiological changes in humans. In particular are the loss of bone and muscle mass. These losses pose a serious problem when considering manned space flight to Mars or other extended space missions. This project seeks to better understand the relationship between strain placed on bones in normal gravity and the molecular signal that tells bone to grow. There is surprisingly little data on this topic. Advancements in our knowledge of the mechanisms of bone loss are aimed toward developing prophylactic therapies for future astronauts. During the course of the summer the student will learn various laboratory techniques, such as strain gauge implantation surgery, hindlimb suspension of rodents (simulating a lack of gravity) and basic histomorphometry. The applications of this research are not limited to manned space flight, but also have implications for future studies of osteoporosis, sports medicine, and orthopedic surgery.

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Background: Much remains to be learned about how plants respond to gravitational inputs. Since growing plants in microgravity is important for future space habitation, growing plants in hypergravity is interesting in that the results obtained may possibly be extrapolated to make predictions about plant reactions to microgravity. Also, the hypergravity environment can be created on Earth and thus experiments using hypergravity are much less expensive as well as easier to conduct. Ames Research Center has outstanding centrifuge facilities available for life science research. Plant hypergravity research, examining both the gross morphological and cell biological effects, will provide direction for future plant gravitational research.

Research Activity: The Astrobiology Academy student will participate in an experiment growing seedlings on a centrifuge under hypergravity conditions. Results will be analyzed using time-lapse video taken during the experiment, as set up by the student. Imaging will also be used in the analysis of plants at the conclusion of the growth experiment. Image measurements of plant growth will lead toward conclusions about how altered gravity quantitatively affects growing plants.

Muriel Ross - SL

Background: the Center began research in 1986 to study and understand the macula (balance organs of the inner ear) of rats flown in space using state-of-the-art three-dimensional reconstruction software, written in-house by the Biocomputation Center team. The reconstruction's are made from a series of ultrathin (0.1 microns) tissue sections digitized under a Ziess 902 Transmission Electron Microscope. Today, we have learned that a number of changes occur in the neural connections of the macula as a result of spaceflight, demonstrating the influence of gravity on neuronal plasticity in the balance organs of the brain. Research on the rat macula continues, with another spaceflight scheduled for April 1998.

Research Activity: the Astrobiology Academy Student will assist Biocomputation Center electron microscopists to study the tissues from the 1998 Neurolab mission. This will include assistance with electron microscopy, image digitization, 3-D reconstruction, and analysis. No experience with microscopy or computational methods are necessary, but students from the biological sciences having familiarity with computers are preferred.

Research Goal: To create and visualize 3-D reconstruction's of macula neurons to compare the effects of spaceflight to 1-g controls.

Background: With a new understanding of neurophysiology, the Biocomputation Center has pioneered the use of 3-D computer simulation and modeling technologies that apply to both biological and computational neural networks. Finite element analysis, traditionally developed for computer-testing of aerospace structures, can now be used to model the functioning neurons of the rat macula. These spatial meshworks are the most sophisticated computational models of neural activity anywhere in the world. Continuing research at the Biocomputation Center involves testing the neural model against known physiological indicators and comparing the model outputs to measured outputs from real neural systems.

Research Activity: the Astrobiology Academy Student will assist Biocomputation Center software engineers to create unique simulation morphologies and monitor the input and output of the computational neural system. A good working knowledge of neural activity is highly recommended and familiarity with basic UNIX commands is required.

Research Goal: to build and test a specific computational neural simulation for comparison with other computational models and to known physiological data.

The objective of our research is to investigate the influence of mechanical forces generated by daily activity on bone density and structure. In the course of our research, we have invented and developed a number of novel technologies including differential pressure loading/unloading during treadmill locomotion, a daily ground reaction force-monitoring system and advanced image-processing of computed tomography (CT) image data. In collaboration with investigators at the Palo Alto Veterans Administration Medical Center and Stanford University, we have developed a mathematical model of bone adaptation that forms the basis of our current experimental research. The specific project assigned to a student would depend on the student's level and background. Experimental projects include the in vitro assessment of material and structural properties of bones using strain gage and imaging techniques and mechanical testing. Analytical studies would include the image-processing of bone densitometry data and high resolution quantitative computed tomography scans in conjunction with a joint VA/NASA/Stanford University effort to investigate bone loss with aging and spinal cord injury.

When astronauts abruptly cross the boundary between disparate gravitational (g) environments, their posture, locomotion, and other bodily movements are severely disrupted. Anecdotal reports and observations of shuttle astronauts reveal unintentional collisions with walls, sudden attacks of vertigo and unsteadiness, and poor hand-eye coordination. Astronauts' inability to engage in rapid and accurate visual-motor coordination, together with their problems of balance, could easily result in tragedy during emergency situations that might occur just as their spacecraft undergoes orbital insertion, arrives at the surface of the Moon or Mars, or touches back down on Earth. At the very least, these problems could cause significant loss of productivity, especially on relatively short missions. Thus, any method of adapting astronauts to these atypical g environments before actually entering them (referred to as "preflight adaptation training") should contribute substantially to astronaut safety and efficiency.

Our project involves the simulation of both the visual and the bodily sensations of walking in the .38-g conditions of Mars (and other gravitational environments). This simulation is accomplished by placing the lower half of the subject’s body in a lower body positive pressure (LBPP) device and having him/her walk on a treadmill while viewing a computer-generated virtual Mars valley through which he/she is walking. Studies will be done first to perfect this Mars gravity simulator and then to demonstrate that subjects are capable of adapting to the simulation while maintaining their normal ability to walk in Earth gravity (1.0 g), a necessary characteristic of any successful form of preflight adaptation training.

The duties of an Astrobiology Academy student would include testing human subjects, placing data in an electronic spreadsheet, and analyzing them by means of the appropriate statistical programs. He/she would also be expected to attend weekly research meetings at which will be discussed research results, problems that may have arisen, etc. The candidate should be able to type well and have had experience with Macintosh computers and programs such as Word and Excel.