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Chronically high infestation of salmon louse (Lepeophtheirus salmonis) questions the sustainability of the Norwegian Atlantic salmon (Salmo salar) aquaculture industry. The confinement of millions of hosts, within hundreds of farms with overlapping larval dispersal kernels create the structure for extremely persistent parasite meta-populations. However, the processes regulating the temporal variation in cross-contamination of pelagic salmon louse stages among farms (i.e. connectivity), a vital process driving louse population dynamics, are not well described. Here, we employ a data driven biophysical dispersal model that reproduces three-and-a-half years of production histories of 132 salmon farms in western Norway and quantifies the connectivity of infective pelagic lice stages among the farms with the ocean currents. We show that although the complex geography of western Norwegian fjords governs the long-term topology of the connectivity network, there was a strong seasonal component to network fragmentation. The main de-structuring agent was the delayed infectivity of the pelagic lice stages at cooler temperatures increasing dispersal distances, enhanced by occasional large scale wind forcing events. Coordinated fallowing strategies and de-lousing treatments only played a marginal role in network fragmentation, suggesting that novel lice restraining strategies that consider the environmentally sensitive transport distances must be developed to successfully break up the connectivity network. [ABSTRACT FROM AUTHOR]

Sea trout face growth-mortality trade-offs when entering the sea to feed. Salmon lice epizootics resulting from aquaculture have shifted these trade-offs, as salmon lice might both increase mortality and reduce growth of sea trout. We studied mortality and behavioural adaptations of wild sea trout in a large-scale experiment with acoustic telemetry in an aquaculture intensive area that was fallowed (emptied of fish) synchronically biannually, creating large variations in salmon lice concentrations. We tagged 310 wild sea trout during 3 years, and gave half of the individuals a prophylaxis against further salmon lice infestation. There was no difference in survival among years or between treatments. In years of high infestation pressure, however, sea trout remained closer to the river outlet, used freshwater (FW) habitats for longer periods and returned earlier to the river than in the low infestation year. This indicates that sea trout adapt their migratory behaviour by actively choosing FW refuges from salmon lice to escape from immediate mortality risk. Nevertheless, simulations show that these adaptations can lead to lost growth opportunities. Reduced growth can increase long-term mortality of sea trout due to prolonged exposure to size-dependent predation risk, lead to lower fecundity and, ultimately, reduce the likelihood of sea migration. [ABSTRACT FROM AUTHOR]

Identification of fetal kidney anomalies invites questions about underlying causes and recurrence risk in future pregnancies. We therefore investigated the diagnostic yield of next‐generation sequencing in fetuses with bilateral kidney anomalies and the correlation between disrupted genes and fetal phenotypes. Fetuses with bilateral kidney anomalies were screened using an in‐house‐designed kidney‐gene panel. In families where candidate variants were not identified, whole‐exome sequencing was performed. Genes uncovered by this analysis were added to our kidney panel. We identified likely deleterious variants in 11 of 56 (20%) families. The kidney‐gene analysis revealed likely deleterious variants in known kidney developmental genes in 6 fetuses and TMEM67 variants in 2 unrelated fetuses. Kidney histology was similar in the latter 2 fetuses—presenting a distinct prenatal form of nephronophthisis. Exome sequencing identified ROBO1 variants in one family and a GREB1L variant in another family. GREB1L and ROBO1 were added to our kidney‐gene panel and additional variants were identified. Next‐generation sequencing substantially contributes to identifying causes of fetal kidney anomalies. Genetic causes may be supported by histological examination of the kidneys. This is the first time that SLIT‐ROBO signaling is implicated in human bilateral kidney agenesis. [ABSTRACT FROM AUTHOR]

The Coxsackievirus A16 (CV-A16) is one of the main pathogens causing hand-foot-and-mouth disease in young children. It is a low-virulence virus rarely involved in serious illness. It is seen sporadically or in outbreaks all over the world. We report a case of sudden unexplained death in infancy, SUDI, in a 3 and 1/2 months old infant, in which a thorough post mortem investigation pointed at a fatal infection with CV-A16 as the most likely cause of death. Only five cases of fatal CV-A16 infection have been published and none of these presented as sudden death. The fatal cases involved two infants, two young children and an elderly man. Post mortem, pre-autopsy CT-scan and C-reactive protein analysis allowed for an autopsy procedure targeted at a microbiological cause of death. The case illustrates the usefulness of supplementary testing during autopsy. [ABSTRACT FROM AUTHOR]

Abstract: The root uptake of lead (Pb) by trees and the transfer of Pb by leaf litter deposition to the forest floor were investigated through a pot experiment with Norway spruce. Natural Pb and radio isotopic lead (210Pb) were determined in needles and twigs and in the pot soil spiked with 210Pb. Calculations of the specific activity in plant material and in the supporting pot soil showed that less than 2% of the Pb content of needles and twigs originates from root uptake and approximately 98% are deposited from the atmosphere. Atmospheric Pb has declined by a factor of 7 from 1980 to 2007 but is still a major pathway of Pb to vegetation and topsoils. The conclusion from the experiment is that the internal circulation of Pb through root uptake, translocation and litterfall, gives an insignificant input of Pb to the forest floor compared to atmospheric deposition. [Copyright &y& Elsevier]

1. The flow in two dimensions of an oscillating incompressible fluid near a circular cylinder with its axis normal to the direction of oscillation, is studied theoretically and experimentally. Starting from Navier-Stoke's differential equations the method of successive approximations has been used in order to get approximative solutions, when the appropriate boundary conditions are applied. The zeroth approximation gives the modified field of oscillation near the cylinder as a function of the viscosity. The first approximation also gives a stationary flow, which is found from the solution of an ordinary linear differential equation of 4th order. 2. Experiments have been carried out in air in a Kundt's tube. The velocities in the plane normal to the axis of the cylinder have been found by photographing smoke particles in air. The experimental and theoretical results agree fairly well. Comparison with corresponding data obtained by Schlichting is also made. Some G functions, derived from Hankel functions which have been used in the theoretical solutions, have been tabulated to 6 digits. [ABSTRACT FROM AUTHOR]