A global assessment of the impact of fisheries-related mortality on shy and white-capped albatrosses: Conservation implications

Hundreds of thousands of seabirds are killed each year as a result of interacting with longline and trawl fishing operations, and the severity of the impact varies regionally. Shy and white-capped albatrosses, Thalassarche cauta and Thalassarche steadi respectively, are phenotypically similar species known to be incidentally killed by fishing operations. The magnitude of this mortality has not previously been assessed across their range. Here we examine recent effort and bycatch rates in fisheries known to incidentally kill these species and qualitatively evaluate the level of impact of each fishery. Results indicate that over 8500 of these albatrosses may be killed annually, although the reliability of this estimate is low due to the paucity of comprehensive observer data in most fisheries. Of the estimated deaths of all seabird species in the fisheries assessed, trawl and longline fisheries killed birds in approximately equal proportions, but when the mortality levels of shy-type albatrosses were examined, trawl fisheries were responsible for 75% of all deaths. Data suggest most of these birds were killed in South African, Namibian and New Zealand demersal trawl fisheries and the South Africa pelagic longline fishery. Because most adult shy albatrosses are comparatively sedentary and rarely found outside Australian waters, it is primarily juvenile shy albatrosses that regularly encounter fishing fleets known to kill large numbers of albatrosses. In contrast, throughout most of their range juvenile and adult white-capped albatrosses are exposed to fisheries that collectively kill many thousands of these albatrosses each year. These data emphasise the urgent need for robust assessments of the impact of bycatch at a species and population level, and the urgent implementation of effective mitigation measures.     

ACVIM consensus statement guidelines for the classification,diagnosis, and management of cardiomyopathies in cats

Cardiomyopathies are a heterogeneous group of myocardial disorders of mostly unknown etiology, and they occur commonly in cats. In some cats, they are well-tolerated and are associated with normal life expectancy, but in other cats they can result in congestive heart failure, arterial thromboembolism or sudden death. Cardiomyopathy classification in cats can be challenging, and in this consensus statement we outline a classification system based on cardiac structure and function (phenotype). We also introduce a staging system for cardiomyopathy that includes subdivision of cats with subclinical cardiomyopathy into those at low risk of life-threatening complications and those at higher risk. Based on the available literature, we offer recommendations for the approach to diagnosis and staging of cardiomyopathies, as well as for management at each stage.     

Endotoxin-induced structural transformations in liquid crystalline droplets

The ordering of liquid crystals (LCs) is known to be influenced by surfaces and contaminants. Here, we report that picogram per milliliter concentrations of endotoxin in water trigger ordering transitions in micrometer-size LC droplets. The ordering transitions, which occur at surface concentrations of endotoxin that are less than 10(-5) Langmuir, are not due to adsorbate-induced changes in the interfacial energy of the LC. The sensitivity of the LC to endotoxin was measured to change by six orders of magnitude with the geometry of the LC (droplet versus slab), supporting the hypothesis that interactions of endotoxin with topological defects in the LC mediate the response of the droplets. The LC ordering transitions depend strongly on glycophospholipid structure and provide new designs for responsive soft matter.     

Investigation of endothelial cells as an in vivo nidus of Anaplasma marginale infection in cattle

Continuous culture of Anaplasma marginale in endothelial cells and the potential implications for vaccine development heightened interest in determining the importance of endothelial cells in the A. marginale life cycle. A. marginale-infection trials were performed to determine if endothelial cells are an in vivo host cell in cattle and if A. marginale from in vitro endothelial cells were infective to cattle. Adult, immunocompetent steers were infected by tick-feeding transmission and were euthanized at different points in the parasitemic cycle. Based on quantitative PCR, the tissue distribution of A. marginale DNA during peak and trough parasitemia was variable with higher quantities observed in spleen, lung, hemal nodes, and abomasum. A. marginale was not conclusively identified in tissue endothelial cells from the steers' tick-bitten dermis or post-mortem tissues using three microscopy techniques (dual indirect immunofluorescence, transmission electron microscopy, and in situ DNA target-primed rolling-circle amplification of a padlock probe). Intravenous inoculation of spleen-intact or splenectomized calves with endothelial cell culture-derived VA isolate A. marginale did not cause seroconversion or clinical anaplasmosis regardless of whether the endothelial culture-derived bacteria were inoculated as host cell-free organisms or within endothelial cells and regardless of the type of endothelial cell culture used - RF/6A primate endothelial cells or primary bovine testicular vein endothelial cells. Data presented here suggest that endothelial cells are likely not a pivotal component of the A. marginale life cycle in vivo.     

Evaluation of the Advanced Canopy-Atmosphere-Soil Algorithm (ACASA) model performance over Mediterranean maquis ecosystem

The Advanced Canopy-Atmosphere-Soil Algorithm (ACASA) model is used to predict energy, water and carbon fluxes over a Mediterranean maquis site located in North-Western Sardinia (Italy) and the model performance is evaluated. Flux simulations are compared with Eddy Covariance field measurements collected from 2004 to 2007. The site experiences a drought season during the summer months in which the vegetation becomes water stressed. Results from the months of January, April, and July are analyzed to demonstrate the model behavior in different environmental conditions. In general, simulated and observed fluxes matched when both the thermal and moisture regime are optimal. During the July water stress period the model underestimated latent heat and carbon fluxes due to a strong stress response linked to soil properties and plant physiological characteristics. The selection of values for key parameters, e.g. maximum ideal photosynthetic capacity (RUBISCO), wilting point, soil water content, and root and leaf area ratio, is crucial to obtain close agreement between simulated and observed fluxes. The model was designed so that the most sensitive parameters are measurable quantities. Using the ACASA model to predict energy and mass fluxes between the vegetation and atmosphere appears promising in this context, and it could significantly improve our ability to estimate fluxes for use in future studies.     

Surface-driven switching of liquid crystals using redox-active groups on electrodes

Electrochemical control of the oxidation state of ferrocene-decorated electrodes leads to surface-driven changes in the orientations of thermotropic liquid crystals. When the electrodes possess nanometer-scale topography, voltages of 0.0 to 0.3 volts (versus a counter electrode in a two-electrode cell) can drive changes in the orientation of the liquid crystals in the plane and/or out of the plane of the electrodes. Electrodes not supporting ferrocene do not lead to surface-driven orientational transitions. The in-plane transitions are driven by the reorganization of the monolayer of ferrocene upon oxidation of ferrocene to ferrocenium. The out-of-plane transition reflects a dielectric coupling between the liquid crystal and the diffuse part of an electrical double layer that evolves upon oxidation of ferrocene to ferrocenium. These results suggest new ways to couple the orientations of liquid crystals to chemical and electrical stimuli in electro-optical devices and chemical sensors.