163 research outputs found

    On the Diameter of Finite Sidon Sets

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    We prove that the diameter of a Sidon set (also known as a Babcock sequence, Golomb ruler, or B2B_2 set) with kk elements is at least k2−bk3/2−O(k)k^2-b k^{3/2}-O(k) where b≤1.96365b\le 1.96365, a comparatively large improvement on past results. Equivalently, a Sidon set with diameter nn has at most n1/2+0.98183n1/4+O(1)n^{1/2}+0.98183n^{1/4}+O(1) elements. The proof is conceptually simple but very computationally intensive, and the proof uses substantial computer assistance. We also provide a proof of b≤1.99058b\le 1.99058 that can be verified by hand, which still improves on past results. Finally, we prove that gg-thin Sidon sets (aka gg-Golomb rulers) with kk elements have diameter at least g−1k2−(2−ε)g−1k3/2−O(k)g^{-1} k^2 - (2-\varepsilon)g^{-1}k^{3/2} - O(k), with ε≥0.02g−2\varepsilon\ge 0.02g^{-2}.Comment: 16 pages, 1 figur

    Genetic protocols for DNA extraction from white-tailed deer cast antlers to confirm individuality

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    White-tailed deer (Odocoileus virginianus) are the most sought-after deer species in America. The antlers of mammals, such as deer, are one of the fastest regenerative tissues in the world and are grown and naturally cast every year. Research on cast antlers have been used for a variety of purposes including population comparisons and impacts of deer health due to climatic stressors. When investigating cast antlers, it is important to confirm individuality of match sets in addition to antlers of the same individual between years. Therefore, individuality must be confirmed genetically, and protocols must be developed and established to do so. Our objectives were to 1) establish a genetic protocol to harvest DNA from cast antlers using connective tissue, and 2) determine individuality from subsequent years and match sets. When fresh antlers are cast, they leave behind a viable connective tissue from which DNA can be extracted. The DNA was successfully extracted from the skin rings harvested from naturally cast antlers. This study developed viable methods to confirm individuality, which aid researchers and wildlife biologists in a better understanding of the white-tailed deer herd as they set management goals and harvest regulations
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