analysis system for the reception of satellite data. A multi-purpose ingest hardware software frame formatter was demonstrated for GOES and TIROS data and work is proceeding on extending the capability to receive GMS data. A similar system was proposed as an archival and analysis system for use with INSAT data and studies are underway to modify the system to receive the planned SeaWiFS (ocean color) data. This system was proposed as the core of a number of international programs in support of U.S. AID activities. Systems delivered or nearing final testing are listed. The NEMS concept and design were initiated from the need to measure and record positional and environmental information during aircraft flights of developmental science research instrumentation. The unit was designed as a stand-alone system which could serve the needs of instruments whose developmental nature did not justify the cost and complexity of including these measurements within the instrument data system. Initially, the system was comprised of a Loran-C receiver and a portable IBM compatible computer recording position and time. Later, the system was interfaced with the Wallops aircraft inertial navigation system (INS), and various other sensors were supplied and shared by the Goddard science users. Real-time position mapping on video monitors was added for investigator's use and information. In 1987, the use of a Global Positioning System (GPS) receiver was included in some missions. A total configuration of the system and the various sensors which can be incorporated are shown. Author N89-28179*# National Aeronautics and Space Administration. W. B. Krabill In its Laboratory for Oceans C04 1988 P 227-229 The Global Positioning System (GPS) network of satellites shows high promise of revolutionizing methods for conducting surveying, navigation, and positioning. This is especially true in the case of airborne or satellite positioning. A single GPS receiver (suitably adapted for aircraft deployment) can yield positioning accuracies (world-wide) in the order of 30 to 50 m vertically, as well as horizontally. This accuracy is dramatically improved when a second GPS receiver is positioned at a known horizontal and vertical reference. Absolute horizontal and vertical positioning of 1 to 2 m are easily achieved over areas of separation of tens of km. If four common satellites remain in lock in both receivers, then differential phase pseudo-ranges on the GPS L-band carrier can be utilized to achieve accuracies of + or - 10 cm and perhaps as good as + or - 2 cm. The initial proof of concept investigation for airborne positioning using the phase difference between the airborne and stationary GPS receivers was conducted and is examined. N89-28180*# Author National Aeronautics and Space Administration. Goddard Space Flight Center, Greenbelt, MD. C43 Abstract Only J. C. Shiue and J. R. Wang 1988 P 231-235 In its Laboratory for Oceans (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 08B Knowledge of soil moisture is important to many disciplines, such as agriculture, hydrology, and meteorology. Soil moisture distribution of vast regions can be measured efficiently only with remote sensing techniques from airborne or satellite platforms. At low microwave frequencies, water has a much larger dielectric constant than dry soil. This difference manifests itself in surface emissivity (or reflectivity) change between dry and wet soils, and can be measured by a microwave radiometer or radar. The Microwave Sensors and Data Communications Branch is developing microwave remote sensing techniques using both radar and radiometry, but primarily with microwave radiometry. The efforts in these areas range from developing algorithms for data interpretation to conducting feasibility studies for space systems, with a primary goal of developing a microwave radiometer for soil moisture measurement from satellites, such as EOS or the Space Station. These efforts are listed. Author N89-28181*# National Aeronautics and Space Administration. D. M. LeVine In its Laboratory for Oceans c35 1988 P 237-238 Realizing the full potential of microwave remote sensing from space requires putting relatively large antennas in orbit. Research is being conducted to develop synthetic aperture antennas to reduce the physical collecting area required of sensors in space, and to possibly open the door to new applications of microwave remote sensing. The technique under investigation involves using a correlation interferometer with multiple baselines. The Microwave Sensors and Data Collection Branch has been engaged in research to develop this technique for applications to remote sensing of soil moisture from space. Soil moisture is important for agricultural applications and for understanding the global hydrologic cycle. An aircraft prototype of an instrument suitable for making such measurements was developed. This is an L-band radiometer called ESTAR which is hoped will become part of the Earth Observing System (EOS). ESTAR is a hybrid instrument which uses both real aperture antennas (long sticks to obtain resolution in the along-track dimension) and aperture synthesis (correlation between sticks to obtain resolution in the cross track dimension). The hybrid was chosen as a compromise to increase the sensitivity (T) of the instrument. Author N89-28182*# National Aeronautics and Space Administration. C43 D. M. LeVine and P. O. Neill In its Laboratory for Oceans 1988 p 239-241 (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 171 Research is being conducted on microwave scattering from vegetation. The objective is to develop techniques for measuring parameters of the vegetation canopy (such as biomass) needed for understanding global biogeochemical cycles and to develop techniques for correcting microwave measurements of soil moisture for the effects of the vegetation canopy. Measurements of vegetation and soil moisture are important for understanding the environment on a global scale. For example, moisture in the soil is an important, highly variable, element in the global hydrologic cycle. The hydrologic cycle, in turn, is strongly coupled to weather and climate through moisture (and energy) fluxes at the surface. The amount and distribution of vegetation is an important element in biogeochemical cycles; and knowledge of both the vegetation canopy and soil moisture is of practical importance in agricultural management. These theories are examined. Author Ames C-130 in support of the First International Field Experiment (FIFE) missions. The study site was over the grassland areas of the Konza Prairie in Kansas. The data collected with ASAS during these flights has been used to produce the first nearly simultaneous multiangular/multispectral images of selected terrestrial study sites. This data will be valuable in the study of surface bidirectional reflectance and albedo. The data will also be useful for the development of data analysis algorithms for future spaceborne instruments such as the Goddard MODIS-T and JPL's HIRIS. The flight data acquired is further analyzed. Author Avail: NTIS HC A12/MF A01 CSCL 02C Agriculture Multiband Experiment Radiometer (Amber) was designed and built in 1979 to 1980 and deployed in 1981. Amber was designed to simultaneously measure sunlight reflected from vegetation in 15 optical bands. In 1982, program interest shifted from ground truth to satellite image reduction and Amber was retired. Early in 1987, the project scientists concluded that Amber, because of its 15 simple and independent optical systems, would be ideally suited to study polarized light. Changes were made to add polarimeter capability to the instrument. The changes are listed Author and briefly discussed. N89-28118 22-48) c36 In its Laboratory (For primary document see CSCL 20E Avail: NTIS HC A12/MF A01 The Laboratory for Oceans is currently working on the development of compact laser diode array (LD) pumped Nd:YAG lasers for use in space-based altimetry and ranging. Laser diode-array pumping technology promises to increase the electrical to optical efficiency of solid state lasers by an order of magnitude with a lifetime increase of nearly three orders of magnitude relative to today's conventional flashlamp-pumped laser systems. The small size, efficiency, and ruggedness make LD-pumped solid state lasers ideal for space based applications. In an in-house RTOP effort, a novel multiple-pass LD-pumped Nd:YAG laser amplifier was designed and tested to increase the 100 microjoule output pulse energy of the Lightwave laser oscillator. Preliminary results have yielded a round trip amplifier gain of about 15 percent using 7 microjoule LD-pump energy. As a parallel activity, funding was recently obtained to investigate the possible use of custom made fiber optic arrays to obtain an efficient optical coupling mechanism between the emitting laser diode-arrays and the target solid state laser material. Fiber optic coupling arrays would allow for the easy manipulation of the spatial emitting pattern of the diode pump an end or side pumping laser to match either Author sources configuration. N89-28186*# National Aeronautics and Space Administration. Goddard Space Flight Center, Greenbelt, MD. LARGE APERTURE SCANNING AIRBORNE LIDAR Abstract Only c36 J. Smith, R. Bindschadler, R. Boers, J. L. Bufton, D. Clem, J. 1988 In its Laboratory for Oceans Garvin, and S. H. Melfi p 253-256 (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 20E A large aperture scanning airborne lidar facility is being developed to provide important new capabilities for airborne lidar sensor systems. The proposed scanning mechanism allows for a large aperture telescope (25 in. diameter) in front of an elliptical flat (25 x 36 in.) turning mirror positioned at a 45 degree angle with respect to the telescope optical axis. The lidar scanning National Aeronautics and Space Administration. Goddard Space Flight Center, Greenbelt, MD. A MULTIPROCESSOR AIRBORNE LIDAR DATA SYSTEM c36 C. W. Wright, S. A. Bailey, G. E. Heath, and C. R. Piazza In its Laboratory for Oceans 1988 p 257-259 (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 20E A new multiprocessor data acquisition system was developed for the existing Airborne Oceanographic Lidar (AOL). This implementation simultaneously utilizes five single board 68010 microcomputers, the UNIX system V operating system, and the real time executive VRTX. The original data acquisition system was implemented on a Hewlett Packard HP 21-MX 16 bit minicomputer using a multi-tasking real time operating system and a mixture of assembly and FORTRAN languages. The present collection of data sources produce data at widely varied rates and require varied amounts of burdensome real time processing and formatting. It was decided to replace the aging HP 21-MX minicomputer with a multiprocessor system. A new and flexible recording format was devised and implemented to accommodate the constantly changing sensor configuration. A central feature of this data system is the minimization of non-remote sensing bus traffic. Therefore, it is highly desirable that each micro be capable of functioning as much as possible on-card or via private peripherals. The bus is used primarily for the transfer of remote sensing data to or from the buffer queue. Author N89-28188*# National Aeronautics and Space Administration. F. J. Schmidlin In its Laboratory for Oceans c47 1988 The meteorological sensor calibration facility is designed to test and assess radiosonde measurement quality through actual flights in the atmosphere. United States radiosonde temperature measurements are deficient in that they require correction for errors introduced by long- and short-wave radiation. The effect of not applying corrections results in a large bias between day time and night time measurements. This day/night bias has serious implications for users of radiosonde data, of which NASA is one. The derivation of corrections for the U.S. radiosonde is quite important. Determination of corrections depends on solving the heat transfer equation of the thermistor using laboratory measurements of the emissivity and absorptivity of the thermistor coating. The U.S. radiosonde observations from the World Meteorological Organization International Radiosonde Intercomparison were used as the data base to test whether the day/night height bias can be removed. Twenty-five noon time and 26 night time observations were used. Corrected temperatures were used to calculate new geopotentials. Day/night bias in the geopotentials decreased significantly when corrections were introduced. Some testing of thermal lag attendant with the standard carbon hygristor took place. Two radiosondes with small bead thermistors imbedded in the hygristor were flown. Detailed analysis was not accomplished; however, cursory examination of the data showed that the hygristor is at a higher temperature than the external thermistor indicates. Author N89-28189*# National Aeronautics and Space Administration. NASA AIRCRAFT-SATELLITE INSTRUMENT CALIBRATION c35 B. W. Guenther In its Laboratory for Oceans 1988 p 267-268 (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 14B Ground based prelaunch calibration of satellite instruments usually is not adequate to provide an accurate characterization of the in-orbit performance of a satellite instrument. This is because the ground calibrations may not simulate the in-orbit environment observations of the satellite sensor, or because the sensor characteristics have changed during launch and in-orbit operations. One technique to obtain a meaningful in-orbit calibration of satellite sensors is to acquire simultaneous observations of an Earth scene with the satellite and a well calibrated aircraft or shuttle sensor which has similar characteristics to the satellite sensor. This is a direct in-orbit calibration technique and is usually called vicarious calibration. The experiment with the control instrument must occur above the sensible atmosphere as measured by the satellite sensor to provide a useful improvement to the calibration of the satellite sensor. Some observations on the experiments are made. RADIANCE STANDARDS Abstract Only 1988 P 277 J. T. McLean In its Laboratory for Oceans (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 14B The Standards and Calibration Office maintains visible and near infrared calibration sources for the use of various GSFC organizations instrument calibration needs and related field activities. These are large aperture spherical and hemispherical integrating sources designed to provide a spatially uniform absolute spectral radiance with a well-defined angular uniformity characteristic. In essence, the calibration and characterization efforts involve monitoring and documenting the stability and the absolute radiance of these calibration sources. These sources are recalibrated on a regular basis to both document any changes that might occur in the output of the sources and to provide the most up-to-date calibration data for the source users. Efforts included comparing the calibration numbers with those of a commercial calibration laboratory that was engaged to do independent calibrations. However, the most recent calibrations done by the independent laboratory and those done by GSFC personnel show a rather large discrepancy (10 to 15 percent). Efforts are underway to resolve these differences. Author J. T. McLean In its Laboratory for Oceans (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 14B c74 1988 P 271-274 Two radiometric calibration sources that are utilized by various groups are maintained and operated. One source is a 6-ft diameter sphere and the other a 4-ft diameter hemisphere. Both are internally coated with multiple layers of barium sulfate and house an array of 12 tungsten filament-quartz iodine lamps that provide a uniform diffuse target of radiance traceable to NBS. The lamps are baffled and arranged so that they are not part of the scene during calibrations. Both systems have a 10-inch viewing aperture. The hemisphere is somewhat more versatile in that the aperture can be changed and the system is movable so calibrations can be done at other sites. Together, these systems have supported numerous GSFC projects and missions during this review period. They are listed. Author This background information relates to the conclusions reached about the GSFC/Optronic calibrations for the 6-foot sphere. Both the hemispherical and the spherical integrating sources were remeasured in February 1988 by two experimenters and the results show a decrease in the output of the sphere. But the discrepancy between GSFC data and Optronic Data remains. The decrease in the output can be accounted for by a correction in the current value of power supplies Number 2 and Number 3. The supplies were running about 1.75 percent high. Minor differences were noted in the short wavelength end of the hemisphere. Efforts to resolve the discrepancy between GSFC and Optronic Labs as well as improve the ability to make more accurate and precise measurements are underway. Author N89-28195# Colorado Univ., Boulder. Center for Astrodynamics OCEAN MODELLING AND THE USE OF ALTIMETRY DATA George Born and Patrick Weidman 1 Feb. 1989 2 p (AD-A206841) Avail: NTIS HC A02/MF A01 CSCL 08/3 The objective of the subject contract was to develop methodology for effectively using satellite altimetry for oceanographic applications. Another task was to examine techniques for measuring and monitoring rotating fluid phenomena. In addition, a task was added later by NORDA to develop ice motion techniques from sequential AVHRR imagery. The ice motion work involved the use of filtered cross correlation between relatively cloud free sequential AVHRR images to examine temporal changes in the patterns of sea ice motion. Most of this work was the interpolation of GEOSAT ERM altimetry time series for the purpose N89-28196# Lamont-Doherty Geological Observatory, Palisades, NY. CLOUD/CRYOSPHERE INTERACTIONS Final Report, Nov. 1985 - Oct. 1988 George Kukla and David A. Robinson (Rutgers - The State Univ., New Brunswick, NJ.) 19 Apr. 1989 46 p (Contract DE-AC02-81EV-10665; AF-AFOSR-0053-86; NSF ATM-83-18676; NSF ATM-85-05558; NSF ATM-87-19865; NSF ATM-87-12020; AF Proj. 2310) (AD-A208377; AFOSR-89-0590TR) Avail: NTIS HC A03/MF CSCL 08/12 A01 Major objectives included investigating cryospheric dynamics, particularly relationships and feedbacks between clouds and the cryosphere when snow cover is forming or dissipating, and assessing algorithms and climatologies used in Air Force (A.F.) operational snow and cloud cover products. Study results have led to increased understanding of: (1) seasonal and interannual variations in snow and cloud cover; (2) dynamics of the onset of melt season in arctic regions; (3) performance of A.F. nephanalyses in marginal cryosphere regions; and (4) performance of the A.F. SNODEP model. Some of the results include: (1) Cloud cover in the Arctic Basin has a late May-early June maximum in extent and thickness, followed by a period of less extensive and thinner cover extending into early August. Cloud conditions are associated with the distribution of surface pressure and the flow of air into the Basin at the surface and aloft; (2) Over arctic lands and sea ice, the timing and duration of the snow melt season, which strongly influence surface mobility of personnel and machinery, vary geographically within a year and across the region from year to year; and (3) Increased spring cloudiness and onset of the melt season over sea ice coincide, suggesting that both are related to northward transport of moist air into the Basin by synoptic disturbances, rather than one solely driving the other. Results over arctic lands are less conclusive. Varying conditions of snow pack, surface albedo, seasonal and latitudinal distribution of solar insolation reaching the top of the atmosphere are among other factors influencing melt. GRA N89-28197# Naval Research Lab., Washington, DC. Acoustic Systems Branch. MODELING OF OCEAN SURFACE SPECTRUM AND SURFACE SCATTERING. APPLICATIONS TO REVERBERATION PREDICTION IN THE AAUS PROGRAM Memorandum Report, Oct. 1983-Sep. 1984 T. D. Ngoc, E. R. Franchi, and B. B. Adams 84 P 23 Jun. 1989 (AD-A210127; NRL-MR-6205) Avail: NTIS HC A05/MF A01 CSCL 20/1 Current scattering theories for sound interaction with the ocean surface and empirical descriptions of the ocean surface wave spectrum are examined for incorporation into the NRL Reverberation Model (RASP). The intent is to provide surface scattering strength estimates using such theories to augment the empirical data bases in surface scattering strength already included in RASP. Since the input surface wave spectrum plays a critical role in determining the scattering strength, a comprehensive assessment of available empirical models of surface wave spectra was performed and the most updated version of the Pierson model was selected for use in combination with the azimuthal distribution model proposed by Mitsuyasu et al. This study focussed on those scattering theories that perform best in the low frequency (less than 500 Hz), low-grazing angle (less than 20 deg) regime. As a result, scattering models such as the small perturbation method and the composite roughness approach were selected for incorporation into RASP in addition to two empirical models, Martin and Chapman-Harris. Illustrations of the surface wave N89-28198# California Univ., Santa Barbara. Marine Science Inst. MOLECULAR BIOLOGY OF THE PHOTOREGULATION OF PHOTOSYNTHETIC LIGHT-HARVESTING COMPLEXES IN MARINE DINOFLAGELLATES Annual Report, 15 Jun. 198815 Jun. 1989 Barbara B. Prezelin and Edward L. Triplett 2 Jun. 1989 14 p (Contract N00014-88-K-0060) (AD-A209650) Avail: NTIS HC A03/MF A01 CSCL 06/3 The goal is to continue to use biotechnological techniques to study the genetic bases of light- and nutrient-regulation of photosynthetic light-harvesting complexes in marine dinoflagellates and their consequences for the bio-optical features of these algae. The studies are significant to determining the molecular bases of environmental regulation of gene expression and photosynthetic performance in marine phytoplankton. Results also contribute to understanding the linkages between light environments and cell optical properties, key elements in physiologically-based bio-optical models being developed to predict ocean primary production. 52 AEROSPACE MEDICINE GRA Includes physiological factors; biological effects of radiation; and effects of weightlessness on man and animals. N89-28199# Los Alamos National Lab., NM. Robert K. Moyzis 1989 15 p Presented at the 6th Conversation in the Discipline Biomolecular Stereodynamics, Albany, NY, 6 Jun. 1989 (Contract W-7405-eng-36) (DE89-014252; LA-UR-89-1989; CONF-8906159-2) Avail: NTIS HC A03/MF A01 An ultimate goal of human genetics is the generation of a complete physical and functional map of the human genome. Twenty-five percent of human DNA, however, consists of repetitive DNA sequences. These repetitive DNA sequences are thought to arise by many mechanisms, from direct sequence amplification by the unequal recombination of homologous DNA regions to the reverse flow of genetic information. A general outline of the chromosomal organization of these repetitive sequences will be discussed. Our working hypothesis is that certain classes of human repetitive DNA sequences encode the information necessary for defining long-range genomic structure. Evidence will be presented that the first goal of this research, the identification and cloning of the human telomere, has been achieved. A human repetitive DNA library was constructed from randomly sheared, reassociated, and oligo(G-C)-tailed DNA, a method that minimizes the potential loss of sequences devoid of a given restriction enzyme site. Sequences too large to clone efficiently in cosmid or lambda vectors, such as centromeric repeats, or telomeric sequences with an end incompatible for cloning, should be present in this library. In order to isolate highly conserved repetitive DNA sequences, this library was screened with radiolabeled hamster Cot50 repetitive DNA. Two clones, containing tandem arrays of the sequence (TTAGGG), were isolated by this method. DOE THE EFFECT OF VARIOUS STRAINING MANEUVERS ON Tom Jennings, Lloyd Tripp, Lora Howell, John Seaworth, and David (AD-A208846; AAMRL-TR-89-011) Avail: NTIS HC A03/MF A01 CSCL 06/5 The purpose of this study was to evaluate the effect of Valsalva (Val), isometric contraction (Iso) and the L-1 maneuvers (L-1) on cardiac volumes at 1G and during 4G. Two-dimensional echocardiography was used to measure volumes. 1G Phase: Eight seated male subjects performed the three maneuvers. The end-diastolic volume (EDV) decreased during Val and L-1 (p less than 0.05). EDV decreased initially but then returned to baseline with Iso. 4G Phase: Seven male subjects experienced three 30 second 4G epochs while performing the three maneuvers. During 4G, 3 of 7 performing Val, 2 of 7 performing Iso, and none performing L-1, experienced peripheral light loss. EDV decreased and stabilized below baseline during the 4Gz epoch (p less than 0.05). Heart rate and cardiac output increased for all maneuvers. Differences between the effects of Val, Iso, and L-1 on G-tolerance do not appear to be related to a differential ability to maintain cardiac volumes. L-1 must provide more G protection due to the isometric contraction component of the maneuver and provide more G protection due to the isometric contraction component of the maneuver and its ability to increase blood pressure. GRA N89-28201# Army Research Inst. of Environmental Medicine, Natick, MA. Health and Performance Div. EFFECTS OF HIGH TERRESTRIAL ALTITUDE ON MILITARY PERFORMANCE Louis E. Banderet and Richard L. Burse 18 Apr. 1989 45 p (AD-A209614; USARIEM-M-33-89) Avail: NTIS HC A03/MF A01 CSCL 06/4 At high altitude, several adverse physical characteristics make coping, functioning, and survival very difficult: hypoxia, cold, wind, dryness, solar radiation, and ultraviolet radiation. The proportion of oxygen in the air is constant at 20.93 percent, even at altitudes up to 100,000 m. The decreased atmospheric pressure at high altitudes results in a proportional reduction of the partial pressure of oxygen (Po2). This lessens the amount of oxygen carried on the blood. The barometric pressures of two regions at the same elevation may differ, since atmospheric pressure also depends on latitude, thickness of the earth's crust, and weather. The relationship between altitude and atmospheric pressure is described in table which include adjustment factors for specific location conditions. GRA N89-28202# Army Research Inst. of Environmental Medicine, Five subjects exercised on a cycle ergometer for 30 min at 55 percent peak VO2 on two occasions in a slightly warm environment. Pyridostigmine bromide (PYR), an acetylcholinesterase (AChE) inhibitor, was ingested (30 mg) approximately 150 min before one experiment, and no drug was administered during the other experiment (control). Red cell AChE inhibition averaged 40 (+ or Esophageal temperature (Tes), a derived mean skin temperature, 7) percent during PYR treatment. forearm blood flow (venous occlusion plethysmography), cutaneous perfusion, and metabolic rate were measured. Cutaneous perfusion decreased after PYR treatment compared to control. Forearm blood flow, which included inactive muscle, skin, fat and bone tissue, was not different between treatments, which implies that blood flow to one of those tissues may have increased while skin blood flow decreased during PYR treatment. The increased threshold for initiation of cutaneous vasodilation with AChE inhibition by PYR suggests that the drug activates central modulation of thermoregulation. One of several possible mechanisms activated may be through increased ACh accumulation at preganglionic sites. This could potentiate adrenergic transmission to cutaneous blood vessels, and enhance vasoconstrictor tone. GRA N89-28203# Rutgers The State Univ., New Brunswick, NJ. EYE MOVEMENTS AND VISUAL INFORMATION PROCESSING (Grant AF-AFOSR-0171-88; AF Proj. 2313) (AD-A209817; AFOSR-89-0808TR) Avail: NTIS HC A02/MF A01 CSCL 05/8 Eye movements place a limit on the processing of visual information because they determine the location and the velocity of the retinal image. Thus, to understand how we see it is necessary to understand how eye moments are controlled. Work this year in my laboratory has concentrated on the roles of expectations and selective attention in the programming of smooth and saccadic eye movements. We have: (1) demonstrated distinct roles for past experience and expectations in the control of smooth eye movement and found that expectation will predominate in the presence of cues about the direction of future motion; (2) found that brisk initial pursuit requires that expectation that target motion will continue; and (3) showed that saccadic eye movements are not attracted to visual backgrounds (as had been claimed) unless subjects pay attention to the background. These studies show that central representations of visual scenes, containing information about the position, motion and future motion of selected objects, are the natural effective stimulus for human eye movement. GRA N89-28204# Colorado State Univ., Fort Collins. E. L. Paulter May 1989 17 p (Grant AF-AFOSR-0189-87; AF Proj. 2312) (AD-A209834; AFOSR-89-0930TR) Avail: NTIS HC A02/MF A01 CSCL 06/10 The phototoxic effect of blue light on isolated pigment epithelium was investigated. The emphasis was on functional changes rather than a description of pathology. The pigment epithelium is analogous to the blood-brain barrier; therefore, the principal functions investigated were the integrity of the barrier system and the transport system and the transport systems known to operate in the pigment epithelium. The effects of blue light on leucine transport across the isolated bovine retinal pigment epithelium (RPE) were continued to determine if Vitamin E and melatonin provided any protective action. Similar studies on the transport of glutamate in the retina to choroid direction were also completed. GRA N89-28205# New York Univ., New York. Dept. of Psychology. HIGHER ORDER MECHANISMS OF COLOR VISION Progress Report No. 1, 15 Sep. 1986- 14 Mar. 1989 John Krauskopf 12 May 1989 16 P (Grant AF-AFOSR-0334-86; AF Proj. 2313) (AD-A209838; AFOSR-89-0931TR) Avail: NTIS HC A02/MF A01 CSCL 06/4 The main accomplishments during this reporting period were: (1) a comprehensive study of the effects of chromatic content, blur and contrast of targets on vernier acuity and on stereo acuity; (2) the use of a new method of measuring chromatic discrimination under conditions of constant adaptation; (3) continuation of the study of the chromatic properties of single cells in the monkey cortex; and (4) experiments on the significance color in the perception of motion. N89-28206# Johns Hopkins Univ., Baltimore, MD. GRA |