Coral reef organisms as bioregion indicators off Halmahera,Moluccas, Indonesia

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Ostreid herpesvirus OsHV‐1 μVar in Pacific oysters Crassostrea gigas (Thunberg 1793) of the Wadden Sea,a UNESCO world heritage site

The Wadden Sea is an extensive wetland area, recognized as UNESCO world heritage site of international importance. Since the mid‐1990s, the invasive Pacific oyster Crassostrea gigas (Thunberg 1793) population in the area has grown exponentially, having a distinct impact on the ecosystem. The recent spread of the emerging oyster pathogen Ostreid herpesvirus OsHV‐1 μVar worldwide and specifically in the oyster culture areas in the south of the Netherlands raised the question whether the virus may also be present in the Wadden Sea. In the summer of 2012 juvenile Pacific oysters were collected from five locations in the Dutch Wadden Sea. The virus was shown to be present in three of the five locations by real‐time PCR and sequencing. It was concluded that OsHV‐1 μVar has settled itself in Pacific oyster reefs in the Wadden Sea. These results and the recent discoveries of OsHV‐1 microvariants in Australia and Korea indicate that OsHV‐1 μVar and related variants might be more widespread than can be deduced from current literature. In particular in regions with no commercial oyster culture, similar to the Wadden Sea, the virus may go undetected as wild beds with mixed age classes hamper the detection of mortality among juvenile oysters.     

Alpha4-integrin (CD49d) expression on bovine peripheral blood neutrophils is related to inflammation of the respiratory system

Neutrophil emigration from the pulmonary vasculature, is mediated by cellular adhesion molecules (CAM) expressed on the outer membranes of endothelial cells and neutrophils. Although beta(2)-integrin-dependent migration is a major mechanism of neutrophil migration, which was demonstrated by extensive invasion of neutrophils in pulmonary tissue of calves suffering from a genetic deficit in expression of beta(2)-integrins, termed bovine leukocyte adhesion deficiency (LAD), the role of alternative CAM is still unclear. We investigated whether an alternate CAM for beta(2)-integrin function, i.e. the alpha(4)-integrin, was expressed on peripheral blood neutrophils of calves. As we detected basal but significant expression, the effect of naturally acquired pulmonary infection on the expression of either integrin was determined, as an indication for its function in the migration process. In our experiments, basal expression of alpha(4)-integrins on peripheral blood neutrophils from clinically healthy calves was detected. On neutrophils of calves, experiencing field outbreaks of enzootic bronchopneumonia, higher expression of the alpha(4)-integrin was detected, which returned to normal after successful treatment of the disease. In addition, its level of expression was linearly related to plasma acute phase protein (haptoglobin) concentrations, which is a sensitive parameter for severity of respiratory inflammation. Increased expression of the alpha(4)-integrin on peripheral blood neutrophils during pulmonary inflammation indicates a role for this CAM in neutrophil migration in the lung.     

The dynamics of sedimentary systems and the whimsicality of policy processes

Background, Aims, and Scope  Sediment management in coastal zones is taking place in high complex environments. Present management options do not have a sophisticated way of dealing with the actual complexity of the physical and the social systems and with the unpredictability that is inherent with these systems. Therefore, a new approach in both policy making and sediment management is needed that takes this complexity into account. The aim of this article is to explore the dynamics in social and natural systems and to draw the contours of this new approach for policy processes and sediment management that fits to the dynamics of the systems. Methods  Three case studies concerning sediment management in Germany and the Netherlands are analysed in this article, in which unpredictability, or whimsicality, appeared through the occurrence of unexpected events. The case studies are analysed from the perspective of complexity theory. Complexity theory is a systemic theory, which means that it explains empirical phenomena from complex system behaviour. To understand the capricious character of sediment management in coastal zones, we need to frame the issue as the interdependency between the physical system and the social system, causing the two systems to develop in mutual adjustment through feedback. The process of mutual adjustment is one that is characterised by a non-linear nature. This is caused by the multiple relationships and the feedback within and between the systems, and the occurrence of chance events. Chance events (surprises) happen suddenly without an apparent cause and are important triggers for change in the systems. In three empirical cases, the occurrence, nature and response to these chance events are analysed as these factors influence the course of sediment management. Results and Discussion  The case studies show that chance events can occur in the biophysical and in the social system. In the three cases, players or actors in the decision process are left with the choice to adapt themselves to the occurring chance events or to refrain from any adaptive behaviour. Chance events can open up new possibilities by activating (new) actors and by coupling to new issues. If the situation is too locked-in (i.e. a stalemate) and is intentional on behalf of the actors, than the chance event will have no effect. There are, however, situations of lock-in that are unintentional, and in such situations a chance event can remove this lock-in. The effects depend largely on the adaptive capacity of the actors to respond adequately and timely to such situations. The adaptive capacity can be increased (and uncertainty reduced) by a better understanding of both the physical and the social system. The case studies show that adaptation is an adequate way of dealing with the occurrence of chance events. Conclusions  We conclude that the way to deal with non-linear developments is through an adaptive policy approach with short feedback loops in order to allow for timely adjustments and learning loops that will progress the understanding of the systems — both social and physical. Besides the instruments that are already available, like modelling and forecasting, instruments like observation and monitoring, stakeholder involvement processes, and learning and adaptation should be developed in this new adaptive approach. Monitoring of the physical system is a key element in this approach as all involved parties and stakeholders can learn how the physical system behaves. In this adaptive approach, whimsicality — that occurs through unexpected events — is an interesting challenge for all concerned with sediment management. Recommendations and Perspectives  The proposed adaptive policy approach should be developed further and should be experimented with in real life situations that are well monitored.     

Contemplations and speculations on novel approaches in the control of fungal plant diseases

Plant disease control can, in principle, be achieved by direct and indirect methods. Novel approaches in direct plant disease control are illustrated by the group of ergosterol biosynthesis inhibitors. Consideration of their stereochemistry leads to speculations on a more rational design of chiral fungicides, with possibly optimised activity against a wider range of fungi. Studies on the mode of action of ergosterol biosynthesis inhibitors, and of the mechanism of resistance to them in fungi, suggest that these phenomena are not causally related. At least in laboratory mutants, resistance seems to be associated with altered membrane function, which may account for reduced fitness, and, in pathogens, for reduced virulence as well. The results of these studies strengthen the conclusion that knowledge of the modes of action and mechanisms of resistance, at the physiological, biochemical and molecular level, should provide a rationale on which to base the design of new systemic fungicides. As a matter of more immediate practical importance, the implications of the use of fungicide-synergist combinations in plant disease control are briefly discussed. With respect to indirect plant disease control, novel approaches should be directed towards the activation of host resistance. However, prospects seem to be limited for the successful application of alternative chemicals that act on host resistance mechanisms by, for instance, inducing phytoalexin synthesis. Controlled activation of host resistance by localised sensitisation of resistance mechanisms may, however, become a promising new method of plant disease control in the future.     

Response of benthic fauna to experimental bottom fishing: A global meta‐analysis

Bottom‐contact fishing gears are globally the most widespread anthropogenic sources of direct disturbance to the seabed and associated biota. Managing these fishing disturbances requires quantification of gear impacts on biota and the rate of recovery following disturbance. We undertook a systematic review and meta‐analysis of 122 experiments on the effects‐of‐bottom fishing to quantify the removal of benthos in the path of the fishing gear and to estimate rates of recovery following disturbance. A gear pass reduced benthic invertebrate abundance by 26% and species richness by 19%. The effect was strongly gear‐specific, with gears that penetrate deeper into the sediment having a significantly larger impact than those that penetrate less. Sediment composition (% mud and presence of biogenic habitat) and the history of fishing disturbance prior to an experimental fishing event were also important predictors of depletion, with communities in areas that were not previously fished, predominantly muddy or biogenic habitats being more strongly affected by fishing. Sessile and low mobility biota with longer life‐spans such as sponges, soft corals and bivalves took much longer to recover after fishing (>3 year) than mobile biota with shorter life‐spans such as polychaetes and malacostracans (<1 year). This meta‐analysis provides insights into the dynamics of recovery. Our estimates of depletion along with estimates of recovery rates and large‐scale, high‐resolution maps of fishing frequency and habitat will support more rigorous assessment of the environmental impacts of bottom‐contact gears, thus supporting better informed choices in trade‐offs between environmental impacts and fish production.     

The raccoon (Procyon lotor) as potential rabies reservoir species in Germany: a risk assessment

Terrestrial wildlife rabies has been successfully eliminated from Germany predominantly as a result of the distribution of oral rabies vaccine baits. In case that wildlife rabies would re-emerge among its known reservoir species in Germany, swift action based on previous experiences could spatially and temporally limit and subsequently control such an outbreak. However, if rabies emerged in the raccoon population in Germany (Procyon lotor), there are no tools or local experience available to cope with this situation. This is especially worrisome for urban areas like Kassel (Hesse) due to the extremely high raccoon population density. A rabies outbreak among this potential reservoir host species in these urban settings could have a significant impact on public and animal health.