Genetic population structure of turbot (Scophthalmus maximus L.) in the Northeast Atlantic was investigated using eight highly variable microsatellite loci. In total 706 individuals from eight locations with temporal replicates were assayed, covering an area from the French Bay of Biscay to the Aaland archipelago in the Baltic Sea. In contrast to previous genetic studies of turbot, we found significant genetic differentiation among samples with a maximum pairwise FST of 0.032. Limited or no genetic differentiation was found among samples within the Atlantic/North Sea area and within the Baltic Sea, suggesting high gene flow among populations in these areas. In contrast, there was a sharp cline in genetic differentiation going from the low saline Baltic Sea to the high saline North Sea. The data were explained best by two divergent populations connected by a hybrid zone; however, a mechanical mixing model could not be ruled out. A significant part of the genetic variance could be ascribed to variation among years within locality. Nevertheless, the population structure was relatively stable over time, suggesting that the observed pattern of genetic differentiation is biologically significant. This study suggests that hybrid zones are a common phenomenon for marine fishes in the transition area between the North Sea and the Baltic Sea and highlights the importance of using interspecific comparisons for inferring population structure in high gene flow species such as most marine fishes.

No abstract

A total of 143 prokaryotic genomes were scored with an updated version of the prokaryotic genefinder EasyGene. Comparison of the GenBank and RefSeq annotations with the EasyGene predictions reveals that in some genomes up to approximately 60% of the genes may have been annotated with a wrong start codon, especially in the GC-rich genomes. The fractional difference between annotated and predicted confirms that too many short genes are annotated in numerous organisms. Furthermore, genes might be missing in the annotation of some of the genomes. We predict 41 of 143 genomes to be over-annotated by >5%, meaning that too many ORFs are annotated as genes. We also predict that 12 of 143 genomes are under-annotated. These results are based on the difference between the number of annotated genes not found by EasyGene and the number of predicted genes that are not annotated in GenBank. We argue that the average performance of our standardized and fully automated method is slightly better than the annotation.

Measurements of the water clarification capacity of a nutrient extractive mussel farm in a eutrophic fjord in Denmark were used to optimize eutrophication mitigation capacity. Graphic: Camille Saurel, DTU Aqua

Effects of excess loading of nutrients to the marine environment can be mitigated by mussel cultures, basically through nutrient removal from the marine environment when shellfish are harvested. Shellfish farming also provide other goods and services to the marine environment primarily through the impact on water transparency caused by shellfish filtration. There is an increasing awareness of the mitigation potential in mussel culture in relation to eutrophication, but so far practical examples of culture on full scale devoted to mitigation are few. Further, impact of mussel farming on nutrient cycling, e.g. in the sediments below the culture units, has raised concerns. In this review, we clarify concepts in relation to nutrient mitigation and discuss goods and services delivered by mussel mitigation cultures and their impact on an ecosystem scale based primarily on results from studies in heavily eutrofied estuaries. A multi-criteria approach for site selection is presented based on experiences from Danish waters, and economic aspects of mitigation cultures are analysed in relation to use of the produced mitigation mussels. Future perspectives for extractive cultures are discussed in relation to source of excess nutrients.

The diagnostic value of a test depends on the variabilityof thetest resultsand theaccuracyofthe test. Theobject of this investigation was to estimate the observer variability and the accuracy, when intrapartum CTGs were assessed by experienced obstetricians. Fifty CTGs were evaluated twice by four obstetricians. They were asked to identify the CTGs belonging to the compromised infants. They were told the criteria for a compromised infant and the incidence (one-third).Eleven (22%) of the CTGs were assessed in the same way of all the Obstetricians in both evaluations. Between the obstetricians, thc accuracy ranged from 50 to 66%. We conclude that the considerable observer variability found in this and other invcstigations must severely impair the clinical value of electronic fetal monitoring (EFM). The variability must be reduced before the "true" predictive value and thecost/benefit of EFM can be estimated. Key worclr: Fetal monitoring, delivery, asphyxia neonatorumT h e value of electronic fetal monitoring (EFM) during delivery has been assessed in several investigations designed with random allocation and controls. Also the latest and largest (1) has only been able t o show a marginal effect of intrapartum EFM.Peter Vest Nielsen, M.D. Akanderhaven 118 DK -2965 Smerum Denmark Acco Obstet Gynecd S a n d 66 11987)

We have examined the human growth hormone (hGH) and human chorionic somatomammotropin (hCS) family of genes in genomic DNA from an individual with complete antenatal deficiency of hCS. Following digestion with a variety of bacterial restriction endonucleases, the DNA from this individual produced fewer fragments with homology to a radiolabeled hCS cDNA probe than did control DNA specimens. The patterns indicated that his DNA contained the normal hGH gene and an "hGH-like" gene, but lacked the hCS gene, a variant hGH gene, and another gene or genes with structural homology to hGH and hCS, which were present in all control DNA specimens. The findings were consistent with homozygosity for a gene deletion with a minimum length of 18.5 kb. Analysis of polymorphic restriction site variation related to the hGH and hCS gene cluster indicated that both parents and three older siblings were heterozygous for the deletion. The association between gene deletion and a normal growth pattern in this individual indicates that hCS and any other peptide hormones encoded by the variant hGH and the other related gene(s) that are deleted in this individual are not required for fetal or extrauterine growth.

In situ microcosms (ISM) and laboratory batch microcosms (LBM) were used for determination of the first-order degradation rate constants of benzene, toluene, o-xylene, nitrobenzene, naphthalene, biphenyl, o- and p-dichlorobenzene, 1,1,1-trichloroethane, tetrachloromethane, trichloroethene, tetrachloroethene, phenol, o-cresol, 2,4- and 2,6-dichlorophenol, 4,6-o-dichlorocresol, and o- and p-nitrophenol in an aerobic aquifer. All aromatic hydrocarbons were degraded in ISM and LBM experiments. The phenolic hydrocarbons were all degraded in ISM experiments, but some failed to degrade in LBM experiments. Chlorinated aliphatic hydrocarbons were degraded neither in ISM nor LBM experiments. Degradation rate constants were determined by a model accounting for kinetic sorption (bicontinuum model), lag phases, and first-order degradation. With a few exceptions, lag phases were less than 2 weeks in both ISM and LBM experiments. First-order degradation rate constants for aromatic and phenolic hydrocarbons ranged between 0.01 and 0.9 day-1. Local variations in first-order degradation rates and variations between rate constants determined by ISM and LBM were generally within a factor of 5, but no systematic differences were observed between rate constants determined in situ and in the laboratory.