This paper compares two distributed operating systems, Amoeba and Sprite. Although the systems share many goals, they diverged on two philosophical grounds: whether to emphasize a distributed computing model or traditional UNIX-style applications, and whether to use a workstation-centered model of computation or a combination of terminals and a shared processor pool. Many of the most prominent ...

Processing on the Amoeba distributed operating system is not fault-tolerant. The only concern of its processing service is to perform load balancing on the existing processors, trying to find the processor that best suits a particular process in terms of memory availability and CPU speed. In this paper we introduce a fault-tolerant processing service for the Amoeba system. This service is used ...

The amoeba of a Laurent polynomial is the image of the corresponding hypersurface under the coordinatewise log absolute value map. In this article, we demonstrate that a theoretical amoeba approximation method due to Purbhoo can be used efficiently in practice. To do this, we resolve the main bottleneck in Purbhoo’s method by exploiting relations between cyclic resultants. We use the same appro...

There are no universal rules for organizing data in XML. Consequently, semantically identical XML documents may have different structures; we call this structural fluctuation in XML. Finding all the structural fluctuations in an XML document requires verbose path expression queries. To overcome this problem, we developed a novel query processing primitive, called amoeba join. Amoeba join does n...

We study the non-archimedean counterpart to the complex amoeba of an algebraic variety, and show that it coincides with a polyhedral set defined by Bieri and Groves using valuations. For hypersurfaces this set is also the tropical variety of the defining polynomial. Using non-archimedean analysis and a recent result of Conrad we prove that the amoeba of an irreducible variety is connected. We i...

In this paper, we present an efficiency improvement for the algorithm called AMOEBA, A Multidirectional Optimum Ecotope-Based Algorithm, devised by Aldstadt and Getis (Geogr Anal 38(4):327–343, 2006). AMOEBA embeds a local spatial autocorrelation statistic in an iterative procedure in order to identify spatial clusters (ecotopes) of related spatial units. We provide an analysis of the computati...

Overwhelming contamination of a continuous cell line with a free-living soil amoeba of the genus Hartmannella is reported. The significance of the finding is discussed because of recent interest shown in the role of this and related species of amoebae in disease of humans. The methods used to detect and identify the amoeba are described and some examples of the amoebae are shown by photomicrogr...

A general molecular mechanics (MM) model for treating aqueous Cu(2+) and Zn(2+) ions was developed based on valence bond (VB) theory and incorporated into the atomic multipole optimized energetics for biomolecular applications (AMOEBA) polarizable force field. Parameters were obtained by fitting MM energies to that computed by ab initio methods for gas-phase tetra- and hexa-aqua metal complexes...

Hydration free energy (HFE) calculations are often used to assess the performance of biomolecular force fields and the quality of assigned parameters. The AMOEBA polarizable force field moves beyond traditional pairwise additive models of electrostatics and may be expected to improve upon predictions of thermodynamic quantities such as HFEs over and above fixed-point-charge models. The recent S...

Naegleria fowleri is a free-living amoeba, known as a causative agent for a fatal disease of the central nervous system (CNS) in man such as Primary amoebic meningoencephalitis (PAM). Factors contributing to its pathogenicity and its distribution in the environment have been investigated by previous researchers. In case of its pathogenicity, several enzymes such as phospolipase A and sphingomye...