3,856 research outputs found
AFLPs: genetic markers for paternity studies in newts (Triturus vulgaris)
DNA-based genetic markers can reveal paternity whenever the direct assignment of fathers to offspring is precluded by multiple matings and internal fertilisation. Microsatellites are the current marker of choice in many behavioural studies, and have revealed important insights into genetic mating systems of European amphibians. However, the number of amphibian species for which the time-consuming designing of locus-specific microsatellite primers was successful is still limited, and the cross-utilisation of existing markers to closely related taxa seems to have a particularly low success rate. Allozymes can infer parentage without a species-specific protocol, but, due to their low degree of polymorphism, in mate choice experiments require the a priori screening of individuals. Dominant markers such as RAPDs successfully identified closely-related amphibian species and their hybrids, but might be less suited to distinguish between closely related individuals with a putatively high frequency of shared bands
Heat budget observations for the FIRE/SRB Wisconsin experiment region from October 9 through November 2, 1986
A map and concise tables are presented which show locations, pixel size, and heat budget products from the NOAA-9 satellite for the FIRE/SRB Wisconsin experiment region during the period 9 October through 2 November 1986. In addition to the operational standard products, a narrowband albedo parameter is calculated and presented based on values from AVHRR band 1. This parameter is useful in identifying and/or quantifying clouds on a global basis using a polar-stereographic grid system
GOES Satellite Observations for the FIRE/SRB Wisconsin Experiment Region from October 11 Through November 2, 1986
A map, concise tables, and satellite images are presented which show ground-site locations, GOES visible/infrared instrument counts above each site, and cloud spatial distribution for the experiment region from 11 October through 2 November 1986. The cloud images are presented near times of the afternoon NOAA-9 satellite overpasses in order to provide a qualitative aid in the interpretation of TOVS, AVHRR, and heat budget data during the FIRE/SRB experiment
Technical innovation changes standard radiographic protocols in veterinary medicine: is it necessary to obtain two dorsoproximal-palmarodistal oblique views of the equine foot when using computerised radiography systems?
Since the 1950s, veterinary practitioners have included two separate dorsoproximal–palmarodistal oblique (DPr–PaDiO) radiographs as part of a standard series of the equine foot. One image is obtained to visualise the distal phalanx and the other to visualise the navicular bone. However, rapid development of computed radiography and digital radiography and their post-processing capabilities could mean that this practice is no longer required. The aim of this study was to determine differences in perceived image quality between DPr–PaDiO radiographs that were acquired with a computerised radiography system with exposures, centring and collimation recommended for the navicular bone versus images acquired for the distal phalanx but were subsequently manipulated post-acquisition to highlight the navicular bone. Thirty images were presented to four clinicians for quality assessment and graded using a 1–3 scale (1=textbook quality, 2=diagnostic quality, 3=non-diagnostic image). No significant difference in diagnostic quality was found between the original navicular bone images and the manipulated distal phalanx images. This finding suggests that a single DPr–PaDiO image of the distal phalanx is sufficient for an equine foot radiographic series, with appropriate post-processing and manipulation. This change in protocol will result in reduced radiographic study time and decreased patient/personnel radiation exposure
Fully permanent magnet atom chip for Bose-Einstein condensation
We describe a self-biased, fully permanent magnet atom chip used to study
ultracold atoms and to produce a Bose-Einstein condensate (BEC). The magnetic
trap is loaded efficiently by adiabatic transport of a magnetic trap via the
application of uniform external fields. Radio frequency spectroscopy is used
for in-trap analysis and to determine the temperature of the atomic cloud. The
formation of a Bose-Einstein condensate is observed in time of flight images
and as a narrow peak appearing in the radio frequency spectrum.Comment: changed title, substantial text modifications, journal reference
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Criteria for the use of regression analysis for remote sensing of sediment and pollutants
Data analysis procedures for quantification of water quality parameters that are already identified and are known to exist within the water body are considered. The liner multiple-regression technique was examined as a procedure for defining and calibrating data analysis algorithms for such instruments as spectrometers and multispectral scanners
Downwelled longwave surface irradiance data from five sites for the FIRE/SRB Wisconsin Experiment from October 12 through November 2, 1986
Tables are presented which show data from five sites in the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment (FIRE)/Surface Radiation Budget (SRB) Wisconsin experiment regional from October 12 through November 2, 1986. A discussion of intercomparison results is also included. The field experiment was conducted for the purposes of both intensive cirrus-cloud measurements and SRB algorithm validation activities
Phase function, backscatter, extinction, and absorption for standard radiation atmosphere and El Chichon aerosol models at visible and near-infrared wavelengths
Tabular values of phase function, Legendre polynominal coefficients, 180 deg backscatter, and extinction cross section are given for eight wavelengths in the atmospheric windows between 0.4 and 2.2 microns. Also included are single scattering albedo, asymmetry factor, and refractive indices. These values are based on Mie theory calculations for the standard rediation atmospheres (continental, maritime, urban, unperturbed stratospheric, volcanic, upper atmospheric, soot, oceanic, dust, and water-soluble) assest measured volcanic aerosols at several time intervals following the El Chichon eruption. Comparisons of extinction to 180 deg backscatter for different aerosol models are presented and related to lidar data
Sub-Poissonian atom number fluctuations by three-body loss in mesoscopic ensembles
We show that three-body loss of trapped atoms leads to sub-Poissonian atom
number fluctuations. We prepare hundreds of dense ultracold ensembles in an
array of magnetic microtraps which undergo rapid three-body decay. The
shot-to-shot fluctuations of the number of atoms per trap are sub-Poissonian,
for ensembles comprising 50--300 atoms. The measured relative variance or Fano
factor agrees very well with the prediction by an analytic
theory () and numerical calculations. These results will facilitate
studies of quantum information science with mesoscopic ensembles.Comment: 4 pages, 3 figure
Pollen and Vertebrates of the Early Neogene Haughton Formation, Devon Island, Arctic Canada
The Haughton Formation of northern Devon Island, arctic Canada, consists of sediments deposited in a lake that filled a large impact crater, which has been dated as early Miocene. The fossiliferous sediments contain a rich assemblage of pollen, some plant megafossils, and the only known early Neogene arctic vertebrates. Common pollen types are Pinus, Ericales, Corylus-type, Betula, and Alnus. Picea, Larix, Cupressaceae, and Ulmus/Zelkova also occur. These taxa, rarer hardwoods, and spores allow a vegetational reconstruction of a mixed conifer-hardwood forest. Climatic conditions were cool temperate with maritime influences. Vertebrates, including trout, smelt, swan, and four mammal genera, lend support to the climatic interpretation, and they also suggest considerable endemism for the mammals. The Haughton flora appears to be bracketed temporally by floras from various parts of the widely distributed Beaufort Formation.
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