The principal focus of this paper is to study carrier pricing decisions for a type of vehicle routing problems defined in a competitive and dynamic environment. This paper introduces the Vehicle Routing Problem in a Competitive Environment (VRPCE), as an extension of the Traveling Salesman Problem with Profits (TSPP) to a dynamic competitive auction environment. In the VRPCE, the carrier must e...

Helical porphyrin nanotubes of tetrakis(4-sulfonatophenyl)porphyrin (TSPP) were examined in DCl/D(2)O solution using resonance Raman and resonance light scattering spectroscopy to probe the influence of hydrogen bonding on the excitonic states. Atomic force microscopy reveals similar morphology for aggregates deposited from DCl/D(2)O and from HCl/H(2)O solution. Deuteration results in subtle ch...

The irradiation of the complex formed by meso-tetrakis (sulfonatophenyl) porphyrin (TSPP) and tubulin was investigated as well as its effects on the structure and function of the protein. We have used tubulin as a model target to investigate whether photoactive ligands docked to the protein can affect the structure and function of the protein upon exposure to visible light. We observed that las...

We improve and derandomize the best known approximation algorithm for the twocriteria metric traveling salesman problem (2-TSP). More precisely, we construct a deterministic 2-approximation which answers an open question by Manthey. Moreover, we show that 2-TSP is randomized (3/2 + ε, 2)-approximable, and we give the first randomized approximations for the two-criteria traveling salesman path p...

Travelling Sales Person Problem is one of the classical combinatorial optimization problems that belong to the NP-complete class. It is the problem of finding the optimized path for a given set of cities. The path is drawn in such a way that the salesperson has to visit each city exactly once. This paper provides an efficient method for solving the classical Travelling Sales Person Problem by u...

Free base porphyrin (PPhe), derivatized with aminosulfonyl groups linked to the aromatic amino acid phenylalanine at the meso-positions, was mixed with DMPC vesicles. The resulting interaction was studied by absorption, steady-state and transient state fluorescence, at different pHs. At pH=2 to pH=9, the aforementioned porphyrin predominates as an aggregated species, with a co-facial arrangemen...

In the historic conference Combinatoire Énumérative [6] wonderfully organized by Gilbert Labelle and Pierre Leroux there were many stimulating lectures, including a very interesting one by Pierre Leroux himself, who talked about his joint work with Xavier Viennot [7], on solving differential equations combinatorially! During the problem session of that very same colloque, chaired by Pierre Lero...

OBJECTIVES Efforts to control tuberculosis (TB) have been hampered by the emergence of multiple-drug resistant strains, necessitating pursuit of alternative approaches to the current antibiotic-based treatments. Herein, we explore the feasibility of photodynamic inactivation (PDI) of mycobacteria. METHODS In vitro PDI studies employing Mycobacterium smegmatis as a surrogate for Mycobacterium ...

Multidimensional binary search tree (abbreviated k-d tree) is a popular data structure for the organization and manipulation of spatial data. The data structure is useful in several applications including graph partitioning, hierarchical applications such as molecular dynamics and n-body simulations, and databases. In this paper, we study e cient parallel construction of k-d trees on coarse-gra...