10,781 research outputs found

    Free-Operant Field Experiences: Differentially Reinforcing Successive Approximations to Behavior Analysis through a ShaperSpace

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    Over the past few years an increasing number of schools and community organizations have developed transformative learning spaces referred to as ΓÇ£MakerSpacesΓÇ¥ for research and training purposes. MakerSpaces are organizations in which members sharing similar interests in science, technology, engineering, and math (STEM) gather to work on self-selected projects. Proponents of MakerSpaces highlight the implicit benefits arising from participantsΓÇÖ increased engagement with complex technical content in a voluntary, authentic context. We extend the MakerSpace concept to applications of training special education teachers to address the needs of students with Autism Spectrum Disorder (ASD). Applied behavior analysis (ABA) has vast empirical support for treating ASD. We believe the MakerSpace model provides a platform for developing a new generation of special education teachers. However, rather than making novel products, the focus is on shaping the behavior-analytic repertoires of special education teachers. In the field of ABA, the term ΓÇ£shapingΓÇ¥ describes the differential reinforcement of successive approximations to a target behavior. Accordingly, we propose the name ShaperSpace to describe a novel clinical training approach to developing special education teachers who employ research-validated interventions for individuals with ASD. The supervision model described in this article is provided, not as a recommendation, but as an exemplar that has developed over four yearsΓÇÖ contingency shaping and continues to be refined. We appeal to the reader to consider the ShaperSpace as a starting point from which skills developed through free-operant field experiences will ultimately be shaped and selected by the naturally occurring contingencies of the environment

    Multiaxis thrust vectoring using axisymmetric nozzles and postexit vanes on an F/A-18 configuration vehicle

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    A ground-based investigation was conducted on an operational system of multiaxis thrust vectoring using postexit vanes around an axisymmetric nozzle. This thrust vectoring system will be tested on the NASA F/A-18 High Alpha Research Vehicle (HARV) aircraft. The system provides thrust vectoring capability in both pitch and yaw. Ground based data were gathered from two separate tests at NASA Langley Research Center. The first was a static test in the 16-foot Transonic Tunnel Cold-Jet Facility with a 14.25 percent scale model of the axisymmetric nozzle and the postexit vanes. The second test was conducted in the 30 by 60 foot wind tunnel with a 16 percent F/A-18 complete configuration model. Data from the two sets are being used to develop models of jet plume deflection and thrust loss as a function of vane deflection. In addition, an aerodynamic interaction model based on plume deflection angles will be developed. Results from the scale model nozzle test showed that increased vane deflection caused exhaust plume turning. Aerodynamic interaction effects consisted primarily of favorable interaction of moments and unfavorable interaction of forces caused by the vectored jet plume

    Cell wall arabinan is essential for guard cell function

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    Stomatal guard cells play a key role in the ability of plants to survive on dry land, because their movements regulate the exchange of gases and water vapor between the external environment and the interior of the plant. The walls of these cells are exceptionally strong and must undergo large and reversible deformation during stomatal opening and closing. The molecular basis of the unique strength and flexibility of guard cell walls is unknown. We show that degradation of cell wall arabinan prevents either stomatal opening or closing. This locking of guard cell wall movements can be reversed if homogalacturonan is subsequently removed from the wall. We suggest that arabinans maintain flexibility in the cell wall by preventing homogalacturonan polymers from forming tight associations

    Mission Design for the Exploration of Ice Giants, Kuiper Belt Objects and Their Moons Using Kilopower Electric Propulsion

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    The exploration of Ice Giants, Kuiper Belt Objects (KBOs) and their moons pose unique challenges from a mission design standpoint. NASA is currently developing a scalable 1-10 kilowatt electric class in-space fission reactor, known as Kilopower. The focus of this paper is to investigate the applicability of Kilopower Electric Propulsion to orbiting missions to Uranus, Neptune, and Pluto. This effort is broken into two pieces for each destination. First, a broad search of interplanetary trajectories with multiple gravity assists is completed to identify a range of mission opportunities from 2025 to 2045. Second, preliminary analysis is completed to understand the accessibility of various destination orbits, including elliptical orbits around the primary body and circular orbits around the largest moons. Results suggest that orbital missions to Uranus and Neptune are feasible with reasonable time of flight. Further work is necessary to achieve similar success with Pluto missions, but preliminary results are promising

    Proposal for interferometric detection of topological defects in modulated superfluids

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    Attractive interactions between fermions can produce a superfluid ground state, in which pairs of up and down spins swirl together in a coordinated, coherent dance. How is this dance affected by an imbalance in the population of up and down fermions? Do the extra fermions stand on the sides, or do they disrupt the dance? The most intriguing possibility is the formation of a modulated superfluid state, known as an LO phase, in which the excess fermions self-organize into domain walls where the pairing amplitude changes sign. Despite fifty years of theoretical and experimental work, there has so far been no direct observation of an LO phase. Here we propose an experiment in which two fermion clouds, prepared with unequal population imbalances, are allowed to expand and interfere. A zipper pattern in the interference fringes is unequivocal evidence of LO physics. Furthermore, because the experiment is resolved in time and in two spatial directions, we expect an observable signature even at finite temperatures (when thermal fluctuations destroy long-range LO order averaged over time)

    The Cosmic Infrared Background Experiment (CIBER): Instrumentation and First Results

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    Ultraviolet emission from the first generation of stars in the Universe ionized the intergalactic medium in a process which was completed by z similar to 6; the wavelength of these photons has been redshifted by (1 + z) into the near infrared today and can be measured using instruments situated above the Earth's atmosphere. First flying in February 2009, the Cosmic Infrared Background ExpeRiment (CIBER) comprises four instruments housed in a single reusable sounding rocket borne payload. CIBER will measure spatial anisotropies in the extragalactic IR background caused by cosmological structure from the epoch of reionization using two broadband imaging instruments, make a detailed characterization of the spectral shape of the IR background using a low resolution spectrometer, and measure the absolute brightness of the Zodiacal light foreground with a high resolution spectrometer in each of our six science fields. The scientific motivation for CIBER and details of its first and second flight instrumentation will be discussed. First flight results on the color of the zodiacal light around 1 mu m and plans for the future will also be presented

    Email-Based Informed Consent: Innovative Method for Reaching Large Numbers of Subjects for Data Mining Research

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    Since the 2010 NASA authorization to make the Life Sciences Data Archive (LSDA) and Lifetime Surveillance of Astronaut Health (LSAH) data archives more accessible by the research and operational communities, demand for data has greatly increased. Correspondingly, both the number and scope of requests have increased, from 142 requests fulfilled in 2011 to 224 in 2014, and with some datasets comprising up to 1 million data points. To meet the demand, the LSAH and LSDA Repositories project was launched, which allows active and retired astronauts to authorize full, partial, or no access to their data for research without individual, study-specific informed consent. A one-on-one personal informed consent briefing is required to fully communicate the implications of the several tiers of consent. Due to the need for personal contact to conduct Repositories consent meetings, the rate of consenting has not kept up with demand for individualized, possibly attributable data. As a result, other methods had to be implemented to allow the release of large datasets, such as release of only de-identified data. However the compilation of large, de-identified data sets places a significant resource burden on LSAH and LSDA and may result in diminished scientific usefulness of the dataset. As a result, LSAH and LSDA worked with the JSC Institutional Review Board Chair, Astronaut Office physicians, and NASA Office of General Counsel personnel to develop a "Remote Consenting" process for retrospective data mining studies. This is particularly useful since the majority of the astronaut cohort is retired from the agency and living outside the Houston area. Originally planned as a method to send informed consent briefing slides and consent forms only by mail, Remote Consenting has evolved into a means to accept crewmember decisions on individual studies via their method of choice: email or paper copy by mail. To date, 100 emails have been sent to request participation in eight HRP-funded studies. The development of the Remote Consent process, the laws allowing transmission of consent via electronic means, total metrics to date, and remaining challenges (e.g., response issues, use of International Partner data, biospecimens/genetic data) for the research use of LSAH/LSDA data will be described

    Observations of the Near-infrared Spectrum of the Zodiacal Light with CIBER

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    Interplanetary dust (IPD) scatters solar radiation which results in the zodiacal light that dominates the celestial diffuse brightness at optical and near-infrared wavelengths. Both asteroid collisions and cometary ejections produce the IPD, but the relative contribution from these two sources is still unknown. The low resolution spectrometer (LRS) onboard the Cosmic Infrared Background ExpeRiment (CIBER) observed the astrophysical sky spectrum between 0.75 and 2.1 μm over a wide range of ecliptic latitude. The resulting zodiacal light spectrum is redder than the solar spectrum, and shows a broad absorption feature, previously unreported, at approximately 0.9 μm, suggesting the existence of silicates in the IPD material. The spectral shape of the zodiacal light is isotropic at all ecliptic latitudes within the measurement error. The zodiacal light spectrum, including the extended wavelength range to 2.5 μm using Infrared Telescope in Space (IRTS) data, is qualitatively similar to the reflectance of S-type asteroids. This result can be explained by the proximity of S-type asteroidal dust to Earth's orbit, and the relatively high albedo of asteroidal dust compared with cometary dust
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