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Scabies has been a scourge among human beings for thousands of years. Its worldwide occurrence with epidemics during war, famine, and overcrowding is responsible for an estimated 300 million people currently infested. Scabies refers to the various skin lesions produced by female mites, and their eggs and scybala that are deposited in the epidermis, leading(More)
We introduce two new combinatorial optimization problems, which are generalizations of the Traveling Salesman Problem (TSP) and the Assignment Problem (AP) and which we call Traveling Salesman Problem of Second Order (TSP2) and Assignment Problem of Second Order (AP2). TSP2 is motivated by an important application in bioinformatics, especially the Permuted(More)
In this paper we improve the analysis of approximation algorithms based on semidefinite programming for the maximum graph parti-(2002) that a parameter-driven random hyperplane can lead to better approximation factors than obtained by Goemans and Williamson (1994). Halperin and Zwick could describe the approximation factors by a mathematical optimization(More)
BACKGROUND No data are available on the incidence and immunoreactivity of autoimmune subepidermal blistering skin diseases in East Africa. METHODS All patients with frank blisters/erosions on the skin and/or mucous membranes that attended the Department of Dermatology at Mbarara University, Uganda, from May 2000 to June 2002, were investigated. The(More)
Based on analysis of 16,392 bp encompassing the complete open reading frames (ORFs) 1, 5, 31, 36, 37, 47, 60, 62, 67, and 68 of the genome of genotype M1 varicella-zoster virus (VZV) was found in swab samples originating from eight Tanzanian zoster patients. Moreover, sequence analysis suggests recombination events between different VZV genotypes within(More)
In this paper we introduce three greedy algorithms for the traveling salesman problem. These algorithms are unique in that they use arc tolerances, rather than arc weights, to decide whether or not to include an arc in a solution. We report extensive computational experiments on benchmark instances that clearly demonstrate that our tolerance-based(More)
In this paper we deal with sensitivity analysis of combina-torial optimization problems and its fundamental term, the tolerance. For three classes of objective functions (Σ, Π, MAX) we give some basic properties on upper and lower tolerances. We show that the upper tolerance of an element is well defined, how to compute the upper tolerance of an element,(More)
MOTIVATION Inference of haplotypes from genotype data is crucial and challenging for many vitally important studies. The first, and most critical step, is the ascertainment of a biologically sound model to be optimized. Many models that have been proposed rely partially or entirely on reducing the number of unique haplotypes in the solution. RESULTS This(More)
Helsgaun has introduced and implemented the lower tolerances (α-values) for an approximation of Held-Karp's 1-tree with the purpose to improve the Lin-Kernighan's Heuristic (LKH) for the Symmetric TSP (STSP). The LKH appears to exceed the performance of all STSP heuristic algorithms proposed to date. In this paper we improve the Helsgaun's LKH based on an(More)