14,690 research outputs found
Gypsy moths and American dog ticks: Space partners
An experiment intended for the space shuttle and designed to investigate the effects of weightlessness and total darkness on gypsy moth eggs and engorged American dog ticks is described. The objectives are: (1) to reevaluate the effects of zero gravity on the termination of diapause/hibernation of embryonated gypsy moth eggs, (2) to determine the effect of zero gravity on the ovipositions and subsequent hatch from engorged female American dog ticks that have been induced to diapause in the laboratory, and (3) to determine whether morphological or biochemical changes occur in the insects under examination. Results will be compared with those from a similar experiment conducted on Skylab 4
Diving Demand for Large Ship Artificial Reefs
Using data drawn from a web-based travel cost survey, we jointly model revealed and stated preference trip count data in an attempt to estimate the recreational use value from diving the intentionally sunk USS Oriskany. Respondents were asked to report their: (i) actual trips from the previous year, (ii) anticipated trips in the next year, and (iii) anticipated trips next year assuming a second diveable vessel (a Spruance class destroyer) is sunk in the same vicinity. Results from several different model specifications indicate average per-person, per-trip use values range from 750. The “bundling†of a second vessel in the area of the Oriskany to create a multiple-ship artificial reef area adds between 1,160 per diver per year in value.Artificial reefs, diving, recreation demand, combined revealed and stated preferences, non-market valuation, Institutional and Behavioral Economics, Marketing, Productivity Analysis, Public Economics, Research Methods/ Statistical Methods, Q26, Q50,
Project for the analysis of technology transfer Quarterly evaluation report, 1 Jan. - 31 Mar. 1969
Technology transfer analysis project studying nonspace applications of NASA and AEC generated technolog
Project for the analysis of technology transfer Quarterly report, 13 Jul. - 12 Oct. 1968
Statistical characteristics of transfer data bank users, and outline of technology transfer and utilization instruction cours
Project for the analysis of technology transfer Quarterly evaluation report, 13 Oct. - 12 Dec. 1968
Technical support package usage documentation by technology transfer analysis projec
Data acquisition electronics and reconstruction software for directional detection of Dark Matter with MIMAC
Directional detection of galactic Dark Matter requires 3D reconstruction of
low energy nuclear recoils tracks. A dedicated acquisition electronics with
auto triggering feature and a real time track reconstruction software have been
developed within the framework of the MIMAC project of detector. This
auto-triggered acquisition electronic uses embedded processing to reduce data
transfer to its useful part only, i.e. decoded coordinates of hit tracks and
corresponding energy measurements. An acquisition software with on-line
monitoring and 3D track reconstruction is also presented.Comment: 17 pages, 12 figure
The experimental observation of Beliaev damping in a Bose condensed gas
We report the first experimental observation of Beliaev damping of a
collective excitation in a Bose-condensed gas. Beliaev damping is not predicted
by the Gross-Pitaevskii equation and so this is one of the few experiments that
tests BEC theory beyond the mean field approximation. Measurements of the
amplitude of a high frequency scissors mode, show that the Beliaev process
transfers energy to a lower lying mode and then back and forth between these
modes. These characteristics are quite distinct from those of Landau damping,
which leads to a monotonic decrease in amplitude. To enhance the Beliaev
process we adjusted the geometry of the magnetic trapping potential to give a
frequency ratio of 2 to 1 between two of the scissors modes of the condensate.
The ratios of the trap oscillation frequencies and
were changed independently, so that we could investigate
the resonant coupling over a range of conditions.Comment: 4 pages including 5 fig
A simplified protocol for detecting two systemic bait markers (Rhodamine B and iophenoxic acid) in small mammals
We developed a method of quantifying levels of fluorescence in the whiskers of wild stoats (Mustela erminea) using fluorescence microscopy and Axiovision 3.0.6.1 software. The method allows for discrimination between natural fluorescence present in or on a whisker, and the fluorescence resulting from the ingestion of the systemic marker Rhodamine B (RB), although some visual judgement is still required. We also developed a new high performance liquid chromatography (HPLC) protocol for detecting the systemic marker iophenoxic acid (IPA) in the blood of laboratory rats (Rattus norvegicus) and wild stoats. With this method, the blood of an animal that has consumed IPA can be tested for the presence of the foreign IPA compound itself. This is a more reliable test than the previous method, which measured the raised level of natural blood protein-bound iodine correlated with IPA absorption. The quantity of blood required from animal subjects is very small (10 μl), so the testing is less intrusive and the method can be extended to smaller species. The extraction technique uses methanol, rather than acids and heavy metal salts, thereby simplifying the procedure. Recovery of IPA is quantitative, giving a highly reliable reading. In experiments on captive rats the IPA method proved successful. Of 12 positively marked carcasses, two that had not been frozen for the 24 h before blood samples were taken showed relatively lower IPA levels. The same IPA detection method, as well as the whisker analysis for RB, was applied successfully to a population of wild stoats to which both Rhodamine B and IPA were made available at bait stations. The presence of both bait markers was detectable in rats for at least 21 days and in stoats for at least 27 days
Purification, growth, and characterization of Zn(x)Cd(1-x)Se crystals
The purification of starting materials which were used in the growth of Zn(x)Cd(1-x)Se (x = 0.2) single crystals using the traveling solution method (TSM) is reported. Up to 13 cm long single crystals and as grown resistivities of 6 x 10(exp 12) ohm/cm could be achieved. Infrared and Raman spectra of Zn(0.2)Cd(0.8)Se are also presented and discussed
Project for the analysis of technology transfer Quarterly report, 1 Apr. 1969 - 30 Jun. 1969
Patterns, statistical analyses, and case studies of transfer and utilization of NASA generated technolog
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