Hypersensitivity reactions caused by ant stings are increasingly recognized as an important cause of death by anaphylaxis. Only some species of ants ( e.g. Solenopsis spp., Myrmecia spp., and Pachycondyla spp.) cause allergic reactions. Ant species are identified by evaluating the morphologic structures of worker ants or by molecular techniques. Ant venom contains substances, including acids an...

The ant(4')-IIa gene was previously cloned from Pseudomonas aeruginosa on a 1.6-kb DNA fragment (G. A. Jacoby, M. J. Blaser, P. Santanam, H. Hächler, F. H. Kayser, R. S. Hare, and G. H. Miller, Antimicrob. Agents Chemother. 34:2381-2386, 1990). In the current study, the ant(4')-IIa gene was localized by gamma-delta mutagenesis. A region of approximately 600 nucleotides which contained the ant(4...

The automaton known as ‘Langton’s ant’ exhibits a dynamical transition from a disordered phase to an ordered phase where the particle dynamics (the ant) produces a regular periodic pattern (called ‘highway’). Despite the simplicity of its basic algorithm, Langton’s ant has remained a puzzle in terms of analytical description. Here I show that the highway dynamics obeys a discrete equation where...

The maintenance scheduling of thermal generators is a large-scale combinatorial optimization problem with constraints. In this paper we introduce the Rank-Based Ant System algorithm based version of the Ant System. This algorithm reinforces local search in neighborhood of the best solution found in each iteration while implementing methods to slow convergence and facilitate exploration.Rank-Bas...

Much has been written concerning the use of raiding swarms of army ants by Neotropical birds in lowland forests. Bird-ant foraging associations are much less common at higher (subtropical) elevations, and no highland species have been identified as professional or regular ant-followers. All known professional army ant followers in the Neotropics occur below 1000 meters elevation (Ridgely & Tudo...

INTRODUCTION Pseudomonas aeruginosa (P. aeruginosa) is one of the primary opportunistic pathogens responsible for nosocomial infections. Aminoglycosides are an import ant component of antipseudomonal chemotherapy. The inactivation of drugs by modifying enzymes is the most common mechanism of aminoglycoside resistance. OBJECTIVES The inactivation of aminoglycosides by modifying enzymes is the ...

We previously demonstrated the substantial capacity for angiotensin (ANG) II formation in the interstitium of the dog heart in vivo. The current study tested the hypothesis that interstitial fluid (ISF) bradykinin (BK) is influenced by ANG II formation. Four microdialysis probes were inserted into the left ventricular myocardium of eight open-chest anesthetized dogs. The probe effluent was coll...

To evaluate the re lat ionship be tween tumor burden and c i rculat ing immune complexes (IC) in ch i ldren with neurob lastoma (NBL), we studied sera col lected at intervals from pat ients with d isseminated (Stage III or IV) NBL. Sera from 10 of 12 pat ients conta ined IC by the Raji cell assay at some time dur ing the first 9 to 11 months of the study. H igher IC levels were observed in sera...

Habitat complexity is a major determinant of structure and diversity of ant assemblages. Following the size-grain hypothesis, smaller ant species are likely to be advantaged in more complex habitats compared to larger species. Habitat complexity can act as an environmental filter based on species size and morphological traits, therefore affecting the overall structure and diversity of ant assem...