Feeding experiments with bbacteria, ciliates and harpacticoid copepods

Many benthic ciliates are known to feed upon bacteria in the marine environment. These may in turn be utilized as food by harpacticoid copepods which graze upon them. Simple non-tracer feeding experiments were carried out in the laboratory with various representatives of these organisms. The growth rates of the ciliate Uronema sp. with different species of bacteria as food, including oil-degrading bacteria, were compared. Results of feeding experiments with the harpacticoid copepod Tisbe holothuriae fed on Uronema sp. show an uptake rate of 12-192 ciliates copepod-1 h-1. The ecological implications are discussed

Entanglement at the quantum phase transition in a harmonic lattice

The entanglement properties of the phase transition in a two dimensional harmonic lattice, similar to the one observed in recent ion trap experiments, are discussed both, for finite number of particles and thermodynamical limit. We show that for the ground state at the critical value of the trapping potential two entanglement measures, the negativity between two neighbouring sites and the block entropy for blocks of size 1, 2 and 3, change abruptly. Entanglement thus indicates quantum phase transitions in general; not only in the finite dimensional case considered in [Phys. Rev. Lett. {\bf 93}, 250404 (2004)]. Finally, we consider the thermal state and compare its exact entanglement with a temperature entanglement witness introduced in [Phys. Rev. A {\bf 77} 062102 (2008)].Comment: extended published versio

Sustained Quantum Coherence and Entanglement in the Avian Compass

In artificial systems, quantum superposition and entanglement typically decay rapidly unless cryogenic temperatures are used. Could life have evolved to exploit such delicate phenomena? Certain migratory birds have the ability to sense very subtle variations in Earth's magnetic field. Here we apply quantum information theory and the widely accepted "radical pair" model to analyze recent experimental observations of the avian compass. We find that superposition and entanglement are sustained in this living system for at least tens of microseconds, exceeding the durations achieved in the best comparable man-made molecular systems. This conclusion is starkly at variance with the view that life is too "warm and wet" for such quantum phenomena to endure.Comment: 4 pages, added journal referenc

CFD investigation of a complete floating offshore wind turbine

This chapter presents numerical computations for floating offshore wind turbines for a machine of 10-MW rated power. The rotors were computed using the Helicopter Multi-Block flow solver of the University of Glasgow that solves the Navier-Stokes equations in integral form using the arbitrary Lagrangian-Eulerian formulation for time-dependent domains with moving boundaries. Hydrodynamic loads on the support platform were computed using the Smoothed Particle Hydrodynamics method. This method is mesh-free, and represents the fluid by a set of discrete particles. The motion of the floating offshore wind turbine is computed using a Multi-Body Dynamic Model of rigid bodies and frictionless joints. Mooring cables are modelled as a set of springs and dampers. All solvers were validated separately before coupling, and the loosely coupled algorithm used is described in detail alongside the obtained results

Host Immune Responses to a Viral Immune Modulating Protein: Immunogenicity of Viral Interleukin-10 in Rhesus Cytomegalovirus-Infected Rhesus Macaques

, consistent with a central role for rhcmvIL-10 during acute virus-host interactions. Since cmvIL-10 and rhcmvIL-10 are extremely divergent from the cIL-10 of their respective hosts, vaccine-mediated neutralization of their function could inhibit establishment of viral persistence without inhibition of cIL-10.As a prelude to evaluating cmvIL-10-based vaccines in humans, the rhesus macaque model of HCMV was used to interrogate peripheral and mucosal immune responses to rhcmvIL-10 in RhCMV-infected animals. ELISA were used to detect rhcmvIL-10-binding antibodies in plasma and saliva, and an IL-12-based bioassay was used to quantify plasma antibodies that neutralized rhcmvIL-10 function. rhcmvIL-10 is highly immunogenic during RhCMV infection, stimulating high avidity rhcmvIL-10-binding antibodies in the plasma of all infected animals. Most infected animals also exhibited plasma antibodies that partially neutralized rhcmvIL-10 function but did not cross-neutralize the function of rhesus cIL-10. Notably, minimally detectable rhcmvIL-10-binding antibodies were detected in saliva.This study demonstrates that rhcmvIL-10, as a surrogate for cmvIL-10, is a viable vaccine candidate because (1) it is highly immunogenic during natural RhCMV infection, and (2) neutralizing antibodies to rhcmvIL-10 do not cross-react with rhesus cIL-10. Exceedingly low rhcmvIL-10 antibodies in saliva further suggest that the oral mucosa, which is critical in RhCMV natural history, is associated with suboptimal anti-rhcmvIL-10 antibody responses

Ingestion of microbially-synthesized organic aggregates and egestion of fecal pellets by marine harpacticoid copepods

Bacteria convert dissolved organic matter (DOM) into detrituslike particles and clump small particles into larger ones, which may then become available to higher consumers. Microbial aggregates produced in the laboratory from DOM and particles <100 µm (both sources derived from freshly collected North Sea macroalgae), were ingested by the epibenthic harpacticoid copepods Paramphiascella vararensis and Tisbe holothuriae in short-term laboratory experiments. The production of fecal pellets was used as an indicator of aggregate consumption. Results showed that between 1-3 pellets copepod-1 h-1 were produced by P. vararensis, independently of algal aggregate source and age. In contrast, T. holothuriae produced between 5-13 pellets copepod-1 h-1 depending on the type of algal aggregate source. Microscopical examination of ageing aggregates and pellets confirmed the presence of a rich bacterial flora as well as some protozoans that may provide nutrients for copepods. Enriched fecal material may also be disaggregated and transformed by microbial action into smaller particles and DOM ("fecal pellet loop"), demonstrating the various pathways for carbon flow within detritus-based nearshore food webs

Accuracy in a finite volume godunov type method

The standard Godunov type method used in computational fluid dynamics shows accuracy problems for low Mach number flows and for the kinetic energy at the highest wave numbers resolvable on a given grid. Both drawbacks become visible when simulating the decay of isotropic turbulence at the low Mach numbers typical for the respective experimental investigations. A modification to cure both problems is proposed by Thornber et al. [10] with a mathematical motivation in case of a special fifth order reconstruction. The theoretical results are repeated here. Numerical results are achieved for schemes not investigated in that literature, namely AUSMDV and AUSM + -up which includes already modifications for low Mach number flows. First experiences with Thornber's modification confirm the positive influence in combination with AUSMDV even if the reconstruction is only of second order. In combination with AUSM + -up Thornber's modification provides too little damping when used without subgrid scale modelling. textcopyright 2013 Springer-Verlag Berlin Heidelberg

Trailing and Leading Edge Flaps for Load Alleviation and Structure Control

This chapter presents the results of numerical computations for a 10-MW wind turbine rotor equipped with the trailing and leading edge flaps. The aerodynamic loads on the rotor are computed using the Helicopter Multi-Block flow solver. The method solves the Navier-Stokes equations in integral form using the arbitrary Lagrangian-Eulerian formulation for time-dependent domains with moving boundaries. The trailing edge flap was located at 75%R, and the leading edge flap was located at 60%R, where R is the radius of the blade. The chapter is divided in the description of employed numerical methods, mesh convergence study, and the cases with trailing and leading edge flaps. Also, the chapter defines flap geometry, deformation and frequency of motion. The blade structure was assumed rigid for all presented cases. The comparison of the flap performance is conducted using non-dimensional parameters, and conclusions are drawn at the end of the chapter