The African termiteraiding ant Pachycondyla analis Latreille (Hymenoptera: Formicidae) organizes group raids on termites of the subfamily Macrotermitinae. Termites and ants occupy and share similar habitats, resulting in a co-evolutionary arms race between termites as prey and ants as predators. The present study explored whether P. analis uses semio- chemical signaling cues to detect potential...

Spherical and cylindrical dielectric cavities support high Q whispering gallery modes due to total internal reflection of the trapped light. When such a cavity is deformed smoothly the ray dynamics of these modes becomes chaotic in a manner determined by the KAM theory of classical hamiltonian dynamics. The universal properties of the ray dynamics predicted by KAM theory allow a general underst...

The health of 36 wild, free-ranging ring-tailed lemurs (Lemur catta) at the Bezà Mahafaly Special Reserve was assessed across 2 habitats of varied human impact: a reserve riverine gallery forest, and a degraded mixed dry deciduous and Alluaudia-dominated spiny forest. While there were no statistically significant differences in leukocyte count or differential between habitats, female lemurs in ...

How many guards are necessary, and how many are sufficient to patrol the paintings and works of art in an art gallery with n walls? This wonderfully na¨ıve question of combinatorial geometry has, since its formulation, stimulated an increasing number of of papers and surveys. In 1987, J. O'Rourke published his book Art Gallery Theorems and Algorithms which has further fueled this area of resear...

Although subterranean termite (Isoptera: Rhinotermitidae) foraging behavior involves the construction of gallery systems in soil, few studies have examined how colony size or soil environmental factors influence rates of construction and morphology of gallery systems. In this study, we investigated the effects of soil texture, soil moisture, and termite density on the rate of tunnel constructio...

Master of Science in Mechanical Engineering and Master of Science in Electrical Engineering and Computer Science In this thesis, we give a pseudo-polynomial time o (log2 n)-approximation algorithm for a variant of the art gallery problem the point-guard problem. The point-guard problem involves finding the minimum number of points and their positions so that guards located at these points cover...

Biometrics has the advantages of efficiency and convenience in identity authentication. As one of the most promising biometric-based methods, ear recognition has received broad attention and research. Previous studies have achieved remarkable performance with multiple samples per person (MSPP) in the gallery. However, most conventional methods are insufficient when there is only one sample per ...

In the Art Gallery problem, given is a polygonal gallery and the goal is to guard the gallery’s interior or walls with a number of guards that must be placed strategically in the interior, on walls or on corners of the gallery. Here we consider a more realistic version: exhibits now have size and may have different costs. Moreover the meaning of guarding is relaxed: we use a new concept, that o...

objectives:the aim of the present study was to assess the analgesic efficacy of iv ketamine injection inaddition to nephrostomy tract infiltration of ketamine – bupivacaine on postoperative pain relief after tubeless percutaneous nephrolithotomy (pcnl). patients and methods: patients (n = 100), with renal stone who were candidates for pcnl were randomized to five groups with 20 cases in each: g...