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The fish ingredient N3-docosahexaenoic acid 22: 6 n-3 (DHA) stimulates brain development. On the other hand methylmercury (MeHg) in fish disturbes the developing central nervous system.

In this Context the IQ score in children is considered as an aggregate measure of in utero brain development.

To determine the effect of DHA exposure on prenatal neurodevelopment the maternal DHA intake during pregnancy was compared with its epidemiologically observed effect on the IQ score of children.

For MeHg the maternal intake was converted into its accumulation in the maternal body. The maternal body burden then was compared with its epidemiologically observed relationship with the IQ score.

Taking the MeHg and DHA content of 33 fish species the net effect of these compounds on the IQ score was quantified. For most fish species the adverse effect of MeHg on the IQ score exceeded the beneficial effect of DHA. In the case of long-living predators a negative effect up to 10 points on the IQ score was found.

The results of this study indicate that food interventions aiming at the beneficial effects of fish consumption should focus on fish species with a high DHA content, while avoiding fish species with a high MeHg content.

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Low field Nuclear Magnetic Resonance was used in comparison to yield and physicochemical measurements to assess the effects of salt and protein injection on the properties of saithe (Pollachius virens) fillets during chilled and frozen storage. Saithe fillets injected with various combinations of salt, homogenized fish proteins, gelatin and fish protein hydrolyzate, were compared to the properties of untreated fillets. Addition of salt or fish protein hydrolyzate resulted in increased yield after cooking and water holding capacity compared to other treatments. Transversal relaxation data fitting resulted in three water populations with relaxation times of 27–45 ms, 60–99 ms and 187–341 ms. Relaxation times and respective populations showed significant correlation to various physicochemical properties, that muscle water behavior was changed by salt and protein injection and indicated protein denaturation during frozen storage. Fish protein hydrolyzate injected fillets were most stable through storage, while gelatin injected fillets were most denatured during frozen storage.

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Effects of added phosphates on retardation of lipid oxidation of salted cod during processing, storage and after rehydration were investigated. Lipid hydrolysis progress and development of color, primary and secondary lipid oxidation products and fluorescence intensities were determined. Added phosphates significantly retarded lipid hydrolysis and lipid oxidation progress, resulting in lower free fatty acid, lipid hydroperoxides (PV), thiobarbituric acid-reactive substances (TBARS) as well as fluorescence intensities (δF _or and δF _aq). Significant correlation between the lipid oxidation products (PV, TBARS, δF _or and δF _aq) and yellow / brownish discoloration (b * value) of salted cod was observed. Principal component analysis showed that TBARS, b * value and δF _or were the strongest indicators of lipid oxidation during salting and storage.

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Contaminants have been determined in blue mussels (Mytilus edulis) at 11 locations around the Icelandic coastline from 1990 to 2010. The aim of the present study was to investigate if there has been a change in concentration of contaminants around the Icelandic coastline for the last two decades and if the concentrations and changes, if present , were consistent between locations. Concentrations of the persistent organic pollutants, p, p′-Dichlorodiphenyldichloroethene (p, p′ -DDE), hexachlorobenzene (HCB), α-hexachlorocyclohexane (α-HCH), polychlorinated biphenyl (PCB-153) and trans-nonachlor, have decreased at most of the sampling locations in Iceland in recent years. However, an increasing trend was found at a few locations that could be explained by anthropogenic activity. The concentration levels of the persistent organics were much lower than found at the Norwegian, USA and Chinese coasts, especially levels of p, p′ -DDE. The concentration of copper and selenium had a consistent pattern of change and concentration between locations over the period which showed a decreasing trend in recent years. The trace elements arsenic, cadmium, mercury and zinc showed more variation in concentration between locations, the concentration of arsenic, mercury and zinc was fairly stable over the period, whereas there were fluctuations in cadmium concentrations. The concentrations of cadmium and zinc were observed to be somewhat higher than found in mussels from Norway, USA and China but values of mercury and lead were much lower in the mussel sampled in Iceland. The higher concentrations of cadmium and zinc can be explained by the volcanic activity in Iceland but no major anthropogenic sources of trace elements are known in Iceland.

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The rapid progress in DNA sequencing technology is resulting in exponential growth in the volume of genome and metagenome sequences. In many cases, standard bioinformatics methods can assign genes to a family, but the exact function of the encoded protein remains unknown. Moreover, the generation of high quality DNA sequence is disproportionately time consuming and expensive. It is, therefore, important to develop methods for the structural and functional automatic annotation for the analysis of lower quality sequence starting from DNA reads. We have developed MEGGASENSE platform for the functional and structural automatic annotation of metagenomes / genomes. The initial functional analysis is carried out on reads before read assembly using in silico translation. However, unlike most other platforms, the resulting protein sequences are scanned using HMMs, which results in more effective detection of genes. Depending on the aims of the analysis, it is possible to use a generic library of profiles or a custom database of choice. The reads are subsequently being assembled. The assembled sequences can be used for 'gene of interest' analysis by BLAST within the platform. Finally, the user can browse the sequences with the Solr search engine, which is implemented within the graphical user interface. The utility of the MEGGASENSE will be illustrated with examples including metagenomes composed of novel anaerobic or microaerophilic heterotrophic species from thermophilic habitats that cover a range of physicochemical conditions. Using MEGGASENSE over 350 reads / genes potentially expressing carbohydrate-modifying enzymes were discovered showing identities ranging from 26 to 100% to genes present in GenBank.

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Fish gelatin and protein solutions prepared from saithe by-products were injected into saithe fillets. Effects on weight changes, water holding capacity, and chemical composition of the fillets were investigated after chilled (2, 5, and 7 days) and frozen (14 and 49 days) storage. The results showed that higher weight yields were obtained by adding proteins and salt to the fillets in comparison with only salt, especially in chilled fillets. The drawback of the injection was that higher drip losses were found during storage and thawing than for untreated fillets. Effects of injection on water content were only significant after 2 days of chilled storage, but differences leveled out after longer storage time and with freezing and thawing of the fillets. The procedure applied in this study seems to be promising for utilization of by-products such as trimmings as an ingredient in higher value products like fillets, in comparison to mince products.

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Modern fisheries already collect vast amount of data, for example, through ERP systems and electronic log-books. It is however well known that the data are rarely used for improving operational decision making. By converting this data into useable information, decision making in the fishing industry could be improved. This paper attempts to show that quantitative methods can be of use in many aspects of decision making in the fishing industry. The paper proposes a hierarchically structured decision support process based on two different optimization models for supporting the long- and short-term decision making in fisheries. For long-term planning the paper proposes a linear optimization model that describes the entire operation of a vertically integrated seafood company. For short-term decision making the paper proposes a mixed integer linear optimization model to assist in organizing vessel trips and deciding catch location with regard to raw material quality and yield obtained in processing.

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Atlantic mackerel (Scomber scombrus L.) is a widely distributed commercially important pelagic species. Little is known about the stock structure of this species, but it is thought to be undergoing a range extension due to environmental changes. Knowledge of the stock structure under these changing conditions is fundamental for effective management. In this paper, 30 highly polymorphic microsatellite loci developed with next generation sequencing are described. The number of alleles per locus ranged from 4 to 39 in two geographically distant populations, observed and expected heterozygosities ranged between 0.370–0.978 and 0.426–0.962, respectively. These loci are an important resource that will allow assessment of the current population genetic structure of this species, and enable monitoring of climate related changes in the species range and distribution.

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Data on distribution, concentration and trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) is scarce in biota from the sub-Arctic region of the Atlantic. The present study is an investigation on PBDE and HBCD concentrations in eggs from seven marine bird species from Iceland, ie common eider (Somateria mollissima), arctic tern (Sterna paradisaea), guillemot (Uria algae), fulmar (Fulmarus glacialis), lesser black-backed gull (Larus fuscus), great black-backed gull (Larus marinus) and great skua (Stercorarius skua). Concentrations of sum PBDEs ranged from 44 ng g⁻¹ fat in eider eggs to 2400 ng g⁻¹ fat in great skua eggs. The contribution of different PBDE congeners to the sum concentration differed between species. Concentration of HBCDs (sum of α−, β^- and γ − HBCD) ranged from 1.3 ng g⁻¹ fat in arctic tern eggs to 41 ng g⁻¹ fat in great black-backed gull. PCA on PBDE and HBCD shows different trends between the two BFR groups, further indicating different sources / usage. Investigations on any potential health or population effects of environmental pollutants on the great skua are advised since both the PBDE and HBCD concentrations are high.

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The genomic architecture underlying ecological divergence and ecological speciation with gene flow is still largely unknown for most organisms. One central question is whether divergence is genome-wide or localized in 'genomic mosaics' during early stages when gene flow is still pronounced. Empirical work has so far been limited, and the relative impacts of gene flow and natural selection on genomic patterns have not been fully explored. Here, we use ecotypes of Atlantic cod to investigate genomic patterns of diversity and population differentiation in a natural system characterized by high gene flow and large effective population sizes, properties which theoretically could restrict divergence in local genomic regions. We identify a genomic region of strong population differentiation, extending over approximately 20 cM, between pairs of migratory and stationary ecotypes examined at two different localities. Furthermore, the region is characterized by markedly reduced levels of genetic diversity in migratory ecotype samples. The results highlight the genomic region, or 'genomic island', as potentially associated with ecological divergence and suggest the involvement of a selective sweep. Finally, we also confirm earlier findings of localized genomic differentiation in three other linkage groups associated with divergence among eastern Atlantic populations. Thus, although the underlying mechanisms are still unknown, the results suggest that 'genomic mosaics' of differentiation may even be found under high levels of gene flow and that marine fishes may provide insightful model systems for studying and identifying initial targets of selection during ecological divergence .

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