Making color infrared film a more effective high altitude sensor

Infrared color film for remote sensors at high altitude

Use of color-coded sleeve shutters accelerates oscillograph channel selection

Sleeve-type shutters mechanically adjust individual galvanometer light beams onto or away from selected channels on oscillograph papers. In complex test setups, the sleeve-type shutters are color coded to separately identify each oscillograph channel. This technique could be used on any equipment using tubular galvanometer light sources

A system of regional agricultural land use mapping tested against small scale Apollo 9 color infrared photography of the Imperial Valley (California)

System of regional agricultural land use mapping tested against Apollo 9 color infrared photography of Imperial Valley, Calif

Identifying a New Gene Required for microRNA-mediated Gene Silencing in \u3cem\u3eDrosophila melanogaster\u3c/em\u3e

Mature microRNAs (miRNA) are ~22 nucleotide long single-stranded ribonucleic acids essential for gene silencing. Silencing occurs when miRNAs are processed via endonucleolytic cleavage and subsequently associate with the miRNA-induced silencing complex (miRISC). miRISC binds via complementary base pairing to target mRNAs, and target mRNAs are silenced by either mRNA degradation, translational block, or both. Knowledge of all genes required for silencing is incomplete. We aim to determine the molecular mechanism of silencing by identifying and characterizing genes required for silencing. A forward genetic screen was performed using EMS mutagenesis of Drosophila melanogaster to generate mutant lines with disrupted gene silencing as visualized by a GFP-based fluorescent reporter of silencing. Locations of EMS-induced mutations are being mapped by determination of recombination frequencies between these mutations and molecularly defined P-element insertions. Preliminary recombination mapping reveals that our mutation of interest (I1-5) is found within a discrete region of the genome on chromosome 3R. A new fly line has also been generated to assist with this preliminary recombination mapping. Future deficiency mapping and complementation tests combining the mutation and alleles of candidate genes will reveal the location of our mutation, and lead us to identify a gene required for micro-RNA mediated gene silencing

Assessment of Southern California environment from ERTS-1

ERTS-1 imagery is a useful source of data for evaluation of earth resources in Southern California. The improving quality of ERTS-1 imagery, and our increasing ability to enhance the imagery has resulted in studies of a variety of phenomena in several Southern California environments. These investigations have produced several significant results of varying detail. They include the detection and identification of macro-scale tectonic and vegetational patterns, as well as detailed analysis of urban and agricultural processes. The sequential nature of ERTS-1 imagery has allowed these studies to monitor significant changes in the environment. In addiation, some preliminary work has begun directed toward assessing the impact of expanding recreation, agriculture and urbanization into the fragile desert environment. Refinement of enhancement and mapping techniques and more intensive analysis of ERTS-1 imagery should lead to a greater capability to extract detailed information for more precise evaluations and more accurate monitoring of earth resources in Southern California

Hamiltonians of Spherically Symmetric, Scale-Free Galaxies in Action-Angle Coordinates

We present a simple formula for the Hamiltonian in terms of the actions for spherically symmetric, scale-free potentials. The Hamiltonian is a power-law or logarithmic function of a linear combination of the actions. Our expression reduces to the well-known results for the familiar cases of the harmonic oscillator and the Kepler potential. For other power-laws, as well as for the singular isothermal sphere, it is exact for the radial and circular orbits, and very accurate for general orbits. Numerical tests show that the errors are always small, with mean errors across a grid of actions always less than 1 % and maximum errors less than 2.5 %. Simple first-order corrections can reduce mean errors to less than 0.6 % and maximum errors to less than 1 %. We use our new result to show that :[1] the misalignment angle between debris in a stream and a progenitor is always very nearly zero in spherical scale-free potentials, demonstrating that streams can be sometimes well approximated by orbits, [2] the effects of an adiabatic change in the stellar density profile in the inner regions of a galaxy weaken any existing 1/r density cusp, which is reduced to $1/r^{1/3}$. More generally, we derive the full range of adiabatic cusp transformations and show how to relate the starting cusp index to the final cusp index. It follows that adiabatic transformations can never erase a dark matter cusp.Comment: 6 pages, MNRAS, in pres

Land use in the northern Coachella Valley

Satellite imagery has proved to have great utility for monitoring land use change and as a data source for regional planning. In California, open space desert resources are under severe pressure to serve as a source for recreational gratification to individuals living in the heavily populated southern coastal plain. Concern for these sensitive arid environments has been expressed by both federal and state agencies. The northern half of the Coachella Valley has historically served as a focal point for weekend recreational activity and second homes. Since demand in this area has remained high, land use change from rural to urban residential has been occurring continuously since 1968. This area of rapid change is an ideal site to illustrate the utility of satellite imagery as a data source for planning information, and has served as the areal focus of this investigation