C. Zheng, Q. Zhu, and D. Sankoff (2007): Given two genomic maps G1 and G2, find a subsequenceG′1 of G1 and a subsequence G′2 of G2 such that the total length of strips in G ′ 1 and G ′ 2 is maximized. • A genomic map is a sequence of gene markers. • A gene marker appears in a genomic map in either positive or negative orientation. • A strip is a maximal string of at least two markers that appea...

It has been shown that the optimal computation of finite field exponentiation is closely related to the problem of finding a suitable addition chain with the shortest possible length. However, obtaining the shortest addition chain for a given arbitrary exponent is a NP-hard problem. Hence in general, we are forced to use some kind of heuristic in order to compute field exponentiation with a sem...

Despite being a favorite delicacy, only 200-300 of the 5,000 known mushroom species have been clearly established to be safe for consumption. Cases of mushroom poisoning have been reported with diverse clinical syndromes. A syndromic classification of mushroom poisoning has recently been developed to facilitate early interventions. We present a series of five cases of mushroom poisoning with mu...

accumulative roll bonding (arb) was used to fabricate the cu-zn multilayer and cu-zn solid solution. a lamellar structure with the hardness of about 130 vhn was formed after eight arb cycles. following to the suitable heat treatment, a solid solution with a uniform microstructure and hardness of about 57 vhn was produced. the dominant wear mechanism in the arb processed multilayer was found to ...

OBJECTIVES To establish if there is an association between ground hardness and injury risk in junior cricket. DESIGN Nested case-series of players who played matches on specific grounds with objective ground hardness measures, within a prospective cohort study of junior community club cricket players. METHODS Monitoring of injuries and playing exposure occurred during 434 matches over the 2...

A sustained-release tablet formulation should ideally have a proper release profile insensitive to moderate changes in tablet hardness that is usually encountered in manufacturing. In this study, matrix aspirin (acetylsalicylic acid) tablets with ethylcellulose (EC), Eudragit RS100 (RS), and Eudragit S100 (S) were prepared by direct compression. The release behaviors were then studied in two co...

background: there are great resources of natural zeolite in iran. zeolite, an inorganic ion-exchanger, may be used as a suitable technical-economical solution for water treatment in many regions of iran. in this study, the characterization of natural zeolite natrolite and the feasibility of removing hardness, cations, and anions were investigated. methods: first, zeolite composition and type we...

We prove the NP-hardness of the problem whether a given word can be derived from a given regular grammar without repeated occurrence of any nonterminal.

We discuss open questions around worst case time and space bounds for NP-hard problems. We are interested in exponential time solutions for these problems with a relatively good worst case behavior.

Building on an existing 2-approximate algorithm for the class of network design problems with downwards-monotone demand functions, many of which are NP-hard, we present an algorithm that produces solutions that are at least as good as and typically better than solutions produced by the existing algorithm.