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Some U.S. farmers are still interested in openpollinated (OP) maize (Zea mays L.), but most varieties are low yielding. How would one develop high-yielding OP varieties, and what are their commercial prospects? To answer this question, we analyzed data from published diallel experiments using Wright's equation. There were seven diallels with inbreds and 14 with populations. The number of inbreds needed to form high yielding synthetics was on average from five to eight lines. The highest predicted yields for composites were on average with three to seven populations. The potential of synthetics and composites as OP varieties in the USA has not been fully examined, though these would probably not be economical for grain in the U.S. Corn Belt. However, their yields may show improvement over current OP varieties and they may be commercially viable in some limited circumstances.

We present a new set of algorithms for segmenting lines, mainly blood vessels in X-ray images, and extracting properties such as their intensities, diameters, and center lines. We developed a tracking algorithm that checks rules taking the properties of vessels into account. The tools even detect veins, arteries, or catheters of two pixels in diameter and with poor contrast. Compared with other algorithms, such as the Canny line detector or anisotropic diffusion, we extract a smoother and connected vessel tree without artifacts in the image background. As the tools depend on common intermediate results, they are very fast when used together. Our results will support the 3-D reconstruction of the vessel tree from stereoscopic projections. Moreover, we make use of our line intensity measure for enhancing and improving the visibility of vessels in 2-D X-ray images. The processed images are intended to support radiologists in diagnosis, radiation therapy planning, and surgical planning. Radiologists verified the improved quality of the processed images and the enhanced visibility of relevant details, particularly fine blood vessels.

A calibration technique for the realistic representation of stereo images is introduced. It guarantees the correct appearance of object distances and sizes irrespective of whether they are imaged on very large or very small screens. If a matching stereo image pair is projected onto several screens of different sizes, the apparent geometry changes from screen to screen. On smaller monitors, all objects seem to be nearer to the spectator and smaller (puppet-theater effect). This paper proves that a global shift between the two stereo frames is necessary and sufficient to reconstruct the 3-D geometry exactly. This shift does not depend on image contents but only on the screen size.