This paper presents two complementary statistical computing frameworks that address challenges in parallel processing and the analysis of massive data. First, the foreach package allows users of the R programming environment to define parallel loops that may be run sequentially on a single machine, in parallel on a symmetric multiprocessing (SMP) machine, or in cluster environments without platform-specific code. Second, the bigmemory package implements memory-and file-mapped data structures that provide (a) access to arbitrarily large data while retaining a look and feel that is familiar to R users and (b) data structures that are shared across processor cores in order to support efficient parallel computing techniques. Although these packages may be used independently, this paper shows how they can be used in combination to address challenges that have effectively been beyond the reach of researchers who lack specialized software development skills or expensive hardware.

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-The gilthead seabream, Sparus aurata, is common in the Mediterranean Sea and along the Atlantic coasts of Portugal, Spain and France. Abundance of S. aurata has recently increased along the Brittany coast, showing good adaptation and acclimatisation to northern waters away from its original distribution range. The physiological adaptations (diet, reproduction, growth) of this fish to colder water could even lead to its colonisation of the English Channel. The ability to eat and digest hard prey makes this fish an important consumer of bivalves. The aim of this study was to make a preliminary evaluation of the diet of the gilthead seabream in its northern range of distribution. Prey items from stomach contents of wild adults from various sites along the East Atlantic coast of France to the English Channel were identified morphologically when it was possible, e.g. in presence of decapod appendices, shells of bivalves, or using DNA barcoding. Diet composition was analysed against sites, fish length and month of sampling using the frequency of occurrence (%F) and weight relative proportion (%W). Results showed that the diet of S. aurata was mainly composed of bivalves, malacostracans and gastropods with a huge dominance of Mytilus sp. (%F = 51.5 and %W = 40.2). This first diet analysis of individuals from the northern range of the species distribution showed its ability, as an opportunistic feeder, to find prey in newly colonised ecosystems and its preference for some organisms, especially mussels.

As languages and systems for rapid prototyping and application development have grown in popularity and the problems that they are being used to solve have grown in size, so has the need for enhancing them with a coordination facility to support distributed and parallel computations and the creation of application ensembles. We describe NetWorkSpace, a coordination facility based on the fundamental concept of a variable/value binding. NetWorkSpace is implemented as an open source server with clients available for a variety of environments. We present an overview of its design, implementation, performance and usage case studies.