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Easy-to-use, economical device permits electrophoresis on all known supporting media. System includes automatic multiple-sample applicator, sample holder, and electrophoresis apparatus. System has potential applicability to fields of taxonomy, immunology, and genetics. Apparatus is also used for electrofocusing.
Because of its size and other unique diurnal-primate characteristics, the squirrel monkey is used in: (1) actual bioflight missions, (2) in laboratory tests designed to clarify the risks to man during launch and recovery as well as in hazardous spaceflight environments; and (3) in the acquisition of data on unknown risks encountered in long duration space exploration. Pertinent data concerning samiri sciureus as described in published and unpublished reports are summarized. Topics include: taxonomy, ethology, life history, sensory-learning-motor capabilities in primate perspective, anatomy and physiology (including homeostatic adaptation to stress), susceptibility to environmental hazards, reproduction, care and clinical management, and previous use in aerospace biomedical research.
Volume 2 of this 2 volume report is represented. This volume contains three appendices: (1) bibliography and cross references; (2) taxonomy - proponents and sources; and (3) concept definitions.
A compendium of soil spectral reflectance curves together with soil test results and site information is presented in an abbreviated manner listing those soil properties most important in influencing soil reflectance. Results are presented for 251 soils from 39 states and Brazil. A narrative key describes relationships between soil parameters and reflectance curves. All soils are classified according to the U.S. soil taxonomy and soil series name for ease of identification.
An attempt was made to redress a critical fault of decisionmaking and problem solving research-a lack of a standard method to classify problem or decision states or conditions. A basic model was identified and expanded to indicate a possible taxonomy of conditions which may be used in reviewing previous research or for systematically pursuing new research designs. A generalization of the basic conditions was then made to indicate that the conditions are essentially the same for both concepts, problem solving and decisionmaking.
A taxonomy of computer science is included, one state of the art of each of the major computer science categories is summarized. A functional breakdown of NASA programs under Aeronautics R and D, space R and T, and institutional support is also included. These areas were assessed against the computer science categories. Concurrent processing, highly reliable computing, and information management are identified.
Studies using different measurement resolutions on a single morphologic feature may yield vastly different measured values for the perimeter. Apparent internal inconsistencies such as these have greatly impeded the numerical taxonomy, description, and modeling of landforms. Fortunately, the underlying internal consistency of measurements can often be reestablished by introducing the Hausdorff-Besicovich dimension into the analysis. This is demonstrated here by the example of perimeter-area ratio measurements made on some of the complicated ejecta deposits that surround many Martian meteorite-impact craters.
The implications of observational findings on atmospheric and subatmospheric taxonomy, diagnostics, and modeling are explored. The correlations between distinctive radial sequences in stellar atmospheres and the thermodynamic properties of the stars in which they appear are discussed.
The chemical analysis of lipids of Prochloron isolated from several hosts is discussed. The object was to determine whether differences in lipid composition could be used to characterize organisms from different sources. Major lipid components are given. An analysis of fatty acid composition of individual lipids slowed a distinctive disstribution of fatty acids. While present results do not justify the use of fatty acid content in the taxonomy of Prochlon, the variations found in the lipids of cells from the same host harvested from different areas, or at different times in the same area, suggest that a study of the effects of temperature and light intensity on lipid composition would be rewarding.
Prokaryotic and eukaryotic evolutionary trees are developed from protein and nucleic-acid sequences by the methods of numerical taxonomy. Trees are presented for bacterial ferredoxins, 5S ribosomal RNA, c-type cytochromes , cytochromes c2 and c', and 5.8S ribosomal RNA; the implications for early evolution are discussed; and a composite tree showing the branching of the anaerobes, aerobes, archaebacteria, and eukaryotes is shown. Single lines are found for all oxygen-evolving photosynthetic forms and for the salt-loving and high-temperature forms of archaebacteria. It is argued that the eukaryote mitochondria, chloroplasts, and cytoplasmic host material are descended from free-living prokaryotes that formed symbiotic associations, with more than one symbiotic event involved in the evolution of each organelle.
To place the arguments advanced in this paper in alternative points of view with regard to mental models are reviewed. Use of the construct in areas such as neural information processing, manual control, decision making, problem solving, and cognitive science are discussed. Also reviewed are several taxonomies of mental models. The available empirical evidence for answering questions concerning the nature and usage of mental models is then discussed. A variety of studies are reviewed where the type and form of humans' knowledge have been manipulated. Also considered are numerous transfer of training studies whose results provide indirect evidence of the nature of mental models. The alternative perspectives considered and the spectrum of empirical evidence are combined to suggest a framework within which research on mental models can be viewed. By considering interactions of dimensions of this framework, the most salient unanswered questions can be identified.
An explicit framework can provide a better understanding of remote sensing models and their interrelationships. This framework distinguishes between the scene, which is real and exists on the ground, and the image, which is a collection of spatially arranged masurements drawn from the scene. The scene model generalizes and parameterizes the essential qualities of the scene. Scene models may be discrete, in which the scene model consists of discrete elements with boundaries, or continuous, in which matter and energy flows are taken to be continuous and there are no clear or sharp boundaries in the scene. In the discrete case, there are two possibilities for models: H- and L-resolution. In the H-resolution case, the resolution cells of the image are smaller than the elements, and thus the elements may be individually resolved. In the L-resolution case, the resolution cells are larger than the elements and cannot be resolved. Most canopy models are L-resolution, deterministic, and noninvertible in nature; image processing models, however, tend to be H-resolution, empirical, and invertible. This taxonomy helps add insight to the development of remote sensing theory and point the way to new, productive areas of research.
This paper focuses on the policy and definitional issues associated with providing adequate and reasonable levels of protection for sensitive systems and data in an agency whose basic charter mandates the open sharing of information and transfer of technology into the market economy. An information model based on current Federal regulatory issuances is presented. A scheme for determining sensitivity levels, based on a categorization taxonomy,is provided.
A goal of the Ada language standardization effort is to promote reuse of software, implying the existence of substantial software libraries and the storage/retrieval mechanisms to support them. A searching/cataloging mechanism is proposed that permits full or partial distribution of the database, adapts to a variety of searching mechanisms, permits a changine taxonomy with minimal disruption, and minimizes the requirement of specialized cataloger/indexer skills. The important observation is that key words serve not only as indexing mechanism, but also as an identification mechanism, especially via concatenation and as support for a searching mechanism. By deliberately separating these multiple uses, the modifiability and ease of growth that current libraries require, is achieved.
Any search for microbial life on Mars cannot rely upon cultivation of indigenous organisms. Only a minority of even terrestrial organisms that are observed in mixed, naturally-occurring microbial populations can be cultivated in the laboratory. Consequently, methods are being developed for analyzing the phylogenetic affiliations of the constituents of natural microbial populations without the need for their cultivation. This is more than an exercise in taxonomy, for the extent of phylogenetic relatedness between unknown and known organisms is some measure of the extent of their biochemical commonalities. In one approach, total DNA is isolated from natural microbial populations and 16S rRNA genes are shotgun cloned for rapid sequence determinations and phylogenetic analyses. A second approach employs oligodeoxynucleotide hybridization probes that bind to phylogenetic group-specific sequences in 16S rRNA. Since each actively growing cell contains about 104 ribosomes, the binding of the diagnostic probes to single cells can be visualized by radioactivity or fluorescence. The application of these methods and the use of in situ cultivation techniques is illustrated using submarine hydrothermal vent communities. Recommendations are made regarding planning toward future Mars missions.
Before interpreting properties of meteorites in terms of putative processes and conditions in the early solar system, it is necessary to understand just what sort of objects meteorites are. Such understanding begins with classification. In this chapter, the current taxonomy of meteorites is summarized, and it is shown how certain stone meteorites, the chondrites, possess chemical and petrographic features that make them potentially attractive as probes of the early solar system. The prevalence of secondary alteration effects, often capable of perturbing the primitive record even in chondrites, is also emphasized.
Topics discussed in this volume include the reappraisal of the moon and Mars/Phobos/Deimos; the origin and evolution of planetary and satellite systems; asteroids, comets, and dust (a post-IRAS perspective); satellite dynamics; future planetary missions; and orbital debris. Papers are presented on a comparison of the chemistry of moon and Mars, the use of a mobile surface radar to study the atmosphere and ionosphere, and laser-ionization studies with the technical models of the LIMA-D/Phobos. Attention is given to planetogonic scenarios and the evolution of relatively mass-rich preplanetary disks, the kinetic behavior of planetesimals revolving around the sun, the planetary evolution of Mars, and pre- and post-IRAS asteroid taxonomies. Consideration is also given to ocean tides and tectonic plate motions in high-precision orbit determination, the satellite altimeter calibration techniques, a theory of the motion of an artificial satellite in the earth atmosphere, ESA plans for planetary exploration, and the detection of earth orbiting objects by IRAS.
Data available on the physical properties of a group of planet-crossing asteroids, the Aten, Apollo, and Amor objects (AAAO) (include data on the taxonomy, mineralogical surface composition, diameter, rotation rate, shape, and surface texture) are presented together with the type of observations used for obtaining these data. These data show that the population of the AAAO is diverse in all of their physical characteristics. This diversity implies that the AAAO come from multiple sources and had different evolutionary histories.