Free-living marine invertebrates occupy one of two environments as adults -the pelagos or the benthos. Many benthic animals nevertheless occupy the pelagos for a short period of time at some stage in their life, be it as gametes or developing larvae. These temporary components of the plankton are referred to as meroplankton, whilst organisms that remain in the plankton for the full duration of their life are known as holoplankton. The length of time that a life cycle stage is resident in the plankton is related to the trophic mode of that stage. Taxa with lecithotrophic larvae or non-feeding life cycle stages tend to be pelagic for relatively short periods of time, and dispersal is comparatively limited (e.g. Scheltema, 1986). Others have planktotrophic larvae that feed whilst in the plankton, and these may be resident for prolonged periods of time during which they undergo extensive and sometimes complex development and can disperse over much greater distances (e.g. Scheltema, 1986;Avise et al., 1987).The evolution of benthic taxa, because of their obvious association with the seabed and their relatively restricted use of the pelagos, is thought to have been strongly influenced by tectonic and climatic events, and vicariance has been suggested to be the major mechanism leading to allopatric speciation (e.g. Springer, 1982;Heads, 2005). The diversity of the marine benthos is comparatively high, and relatively few species are ABSTRACT Aim Using the genus as the unit of analysis, we examine the relationship between richness, distribution and life cycle strategy for all currently recognized marine Hydrozoa.Location The global marine environment.Methods A global dataset detailing the number of species per genus and the mean date of first description (as a proxy for geographic range size) per genus was assembled for all currently recognized marine Hydrozoa. Differences in means per genus were examined by dominant life cycle strategy (holoplanktic, meroplanktic and benthic) using nonparametric ANOVA and resampling methods.Results By comparison with benthic taxa, holopelagic genera are (on average) significantly less species rich and were described at a significantly earlier date. Taxa with meroplanktic life cycles have a richness and a date of first description that is mid-way between the two extremes.Main conclusions Following from previous work showing that there is a negative relationship between the date of first description and geographic range size, our data indicate that holopelagic taxa not only have fewer species per genus but also have a wider distribution than benthic taxa. These quantitative results are in agreement with long-standing intuitions, and should be applicable to other taxa. They run counter to some recent genetic observations that suggest taxa having planktic larvae might nevertheless show restricted distributions; we argue that this inference reflects a lack of sampling of holopelagic taxa, and a call is made to provide empirical evidence from this realm.

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have patents filed for the use of suPAR levels in the management of cardiovascular disease and the use anti-suPAR therapies as a strategy to prevent and treat atherosclerosis. SSH and JR are scientific advisory board members of Walden Biosciences, a company devising therapeutics targeting suPAR in kidney disease. GH, MEH, JBN and LAL receive salary, stocks and stock options from Regeneron Pharmaceuticals, Inc. JEO is a co-founder, shareholder, and chief scientific officer of Virogates and a named inventor on patents related to suPAR.

Unmanned aerial vehicles (UAVs) or drones are increasingly used in cities to provide service tasks that are too dangerous, expensive or difficult for human beings. Drones are also used in cases where a task can be performed more economically and or more efficiently than if done by humans. These include remote sensing tasks where drones can be required to form coalitions by pooling their resources to meet the service requirements at different locations of interest in a city. During such coalition formation, finding the shortest path from a source to a location of interest is key to efficient service delivery. For fixed-wing UAVs, Dubins curves can be applied to find the shortest flight path. When a UAV flies to a location of interest, the angle or orientation of the UAV upon its arrival is often not important. In such a case, a simplified version of the Dubins curve consisting of two instead of three parts can be used. This paper proposes a novel model for UAV coalition and an algorithm derived from basic geometry that generates a path derived from the original Dubins curve for application in remote sensing missions of fixed-wing UAVs. The algorithm is tested by incorporating it into three cooperative coalition formation algorithms. The performance of the model is evaluated by varying the number of types of resources and the sensor ranges of the UAVs to reveal the relevance and practicality of the proposed model.

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