Overview Each year the commercial carrot crop in Wisconsin suffers losses from alternaria leaf blight, cercospora leaf spot, and aster yellows. The first two are diseases caused by fungi (Alternaria dauci and Cercospora carotae). The third is a disease caused by the aster yellows phytoplasma, a parasitic bacterium of carrot phloem tissue and also of the aster leafhopper (Macrosteles quadrilinea...

The aster yellows phytoplasma (AYp) is transmitted by the aster leafhopper, Macrosteles quadrilineatus Forbes, in a persistent and propagative manner. To study AYp replication and examine the variability of AYp titer in individual aster leafhoppers, we developed a quantitative real-time polymerase chain reaction assay to measure AYp concentration in insect DNA extracts. Absolute quantification ...

ASTER is a high-spatial resolution, multispectral imaging system flying aboard TERRA, a satellite launched in December 1999 as part of NASA’s Earth Observing System (EOS). An ASTER scene covering 61.5 km x 63 km contains data from 14 spectral bands. An ASTER Digital Elevation Model (DEM) is generated using bands 3N (nadir) and 3B (backward) level 1A images acquired by the Visible Near Infra-red...

The mitotic spindle positions the cytokinesis furrow. The cytokinesis furrow then forms and ingresses at the site of the mitotic spindle, between the spindle poles. Two populations of spindle microtubules are implicated in cytokinesis furrow positioning: radial microtubule arrays called asters and bundled non-kinetochore microtubules called the spindle midzone. Here I will discuss our recent re...

The optical sensor ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) on board the Terra satellite offers new possibilities for worldwide glacier monitoring. In this paper, its capability and accuracy for selected glaciological applications is evaluated. (a) ASTER’s along-track stereo sensor allows for photogrammetric DEM generation. Here, we apply PCI Geomatica Orthoengine ...

IN a previous communication (Raven, Escher, Herrebout, & Leussink, 1958) the maturation of the egg was described in Agriolimax reticulatus, Limax flavus, and Limnaea stagnalis, with special regard to the formation of the second maturation spindle. In the three species the second maturation spindle arises by direct transformation from the deep centrosphere of the first maturation amphiaster. In ...

Synergistic applications of multi-resolution satellite data have been of a great interest among user communities for the development of an improved and more effective operational monitoring system of natural resources, including vegetation and soil. In this study, we conducted an inter-comparison of two remote sensing products, namely, visible/near-infrared surface reflectances and spectral veg...

0099-1112/08/7403–0 /$3.00/0 © 2008 American Society for Photogrammetry and Remote Sensing Abstract In this study, we developed a land-cover classification methodology using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) visible near-infrared (VNIR), shortwave infrared (SWIR), and thermal infrared (TIR) band combinations based on wavelet fusion and the selforganizing map...

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on-board the National Aeronautics and Space Administration’s (NASA’s) Terra spacecraft provides along-track digital stereo image data at 15-m resolution. As part of ASTER digital elevation model (DEM) accuracy evaluation efforts by the US/Japan ASTER Science Team, stereo image data for four study sites around the world h...

On several days in 2000 & 2001 the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) on the Terra satellite obtained data over the Jornada Experimental Range test site along the Rio Grande river and the White Sand National Monument in New Mexico. ASTER has 14 channels from the visible (VNIR) through the thermal infrared (TIR) with 15 m resolution in the VNIR and 90 m in the...