Distributed environmental control

We present an architecture of distributed, independent control agents designed to work with the Computer Aided System Engineering and Analysis (CASE/A) simulation tool. CASE/A simulates behavior of Environmental Control and Life Support Systems (ECLSS). We describe a lattice of agents capable of distributed sensing and overcoming certain sensor and effector failures. We address how the architecture can achieve the coordinating functions of a hierarchical command structure while maintaining the robustness and flexibility of independent agents. These agents work between the time steps of the CASE/A simulation tool to arrive at command decisions based on the state variables maintained by CASE/A. Control is evaluated according to both effectiveness (e.g., how well temperature was maintained) and resource utilization (the amount of power and materials used)

La biblioteca digital: mitos y retos

El objetivo de este artículo es sencillo: provocar. Queremos refutar la codicia tecnológica y el exceso retórico que son característicos de buena parte de los informes sobre las “bibliotecas digitales”. Buscamos la polémica como contrapeso para todo ese material que han lanzado las empresas tecnológicas, los políticos y las revistas informáticas, los mismos –por cierto– que nos ofrecieron la “oficina sin papeles” y que predijeron “la muerte del libro”. Lejos de nosotros, no obstante convocar a un levantamiento neo-ludita contra los avances y la tecnología de las “bibliotecas digitales”. Las “bibliotecas digitales” no son un desperdicio de tiempo y de dinero

Effect of Feeding Distillers Grains and Supplementing with Dietary Antioxidants on Ground Beef Shelf Life and Fatty Acid Profile

Ground beef from cattle fed corn- based diets with no wet distillers grains, wet distillers grains plus solubles, wet distillers grains + 1000 IU/hd/d vitamin E, wet distillers grains + 150 ppm/hd/d, Ethoxyquin/ TBHQ (Agrado Plus, Novus International, St. Louis, MO), or wet distillers grains + 500 IU/hd/d vitamin E + 150 ppm/hd/d Ethoxyquin/ TBHQ during the finishing phase were compared to analyze lipid oxidation and fatty acid composition. All ground beef lipid oxidation (raw or cooked) increased over time. Raw beef samples from cattle supplemented vitamin E sustained lower TBARS values than corn aft er 2 d of simulated retail display. An increase in PUFA and C18:2 was observed in lean and composite fatty acids in WDGS versus corn finished cattle. Th e potential susceptibility to oxidation found by feeding distillers grains was counteracted by supplementation of Vitamin E in the diet

Octocorals in the Galapagos Islands

The Galapagos octocorals were almost unknown until recent years. Of the three orders within the subclass Octocorallia (Anthozoa, Cnidaria), the Pennatulacea (sea pens) and Alcyonacea (soft corals and gorgonians) occur in the Galapagos. Recent collections and research bring the total known octocorallian fauna to three sea pens (Virgularia galapagensis, Ptilosarcus undulatus and Cavernulina darwini) and 15 gorgonians. Of the 13 gorgonians that we have collected, several are new species. Pacifigorgia is widely distributed in the archipelago, with four named species (P. dampieri, P. symbiotica, P. rubripunctata, and P. darwinii), three of them recently described, and two others yet to be described. The genus Muricea contains three widely distributed undescribed species, one of which appears in three chromotypes, and one deepwater species that has not been collected recently. Two species of Heterogorgia occur in the central archipelago, H. verrucosa and the recently described and widely distributed H. hickmani. The remaining gorgonians are Eugorgia daniana, Leptogorgia alba and Adelogorgia telones

Benthic-Pelagic Coupling in Northern Gulf of Mexico Estuaries: Do Benthos Feed Directly on Phytoplankton?

Few of the dominant benthic taxa of the northern Gulf of Mexico feed directly on phytoplankton. Rather, most of them feed on near-bottom seston and detritus. This is in contrast to models for Chesapeake Bay and San Francisco Bay. We found that detritivores represented over 80% of the macrobenthic organisms and over 90% of the biomass in Gulf of Mexico estuaries. The paucity of benthos that consumed phytoplankton led us to hypothesize that macrobenthos in Gulf of Mexico estuaries had less effect on plankton communities than was documented in U.S. east coast and west coast estuaries, where benthic communities consumed much of the water-column production. We provided as evidence gut-contents analyses of dominant taxa, the feeding morphology of suspension feeders (especially clams), and the lack of vertical mixing or strong turbulent flow that is necessary for benthos to remove substantial portions of the phytoplankton