Sex determination in fish is a labile character in evolutionary terms. The sex-determining (SD) master gene can differ even between closely related fish species. This group is an interesting model for studying the evolution of the SD region and the gonadal differentiation pathway. The turbot (Scophthalmus maximus) is a flatfish of great commercial value, where a strong sexual dimorphism exists for growth rate. Following a QTL and marker association approach in five families and a natural population, we identified the main SD region of turbot at the proximal end of linkage group (LG) 5, close to the SmaUSC-E30 marker. The refined map of this region suggested that this marker would be 2.6 cM and 1.4 Mb from the putative SD gene. This region appeared mostly undifferentiated between males and females, and no relevant recombination frequency differences were detected between sexes. Comparative genomics of LG5 marker sequences against five model species showed no similarity of this chromosome to the sex chromosomes of medaka, stickleback, and fugu, but suggested a similarity to a sex-associated QTL from Oreochromis spp. The segregation analysis of the closest markers to the SD region demonstrated a ZW/ZZ model of sex determination in turbot. A small proportion of families did not fit perfectly with this model, which suggests that other minor genetic and/or environmental factors are involved in sex determination in this species.

Background Genomic relationship matrices are used to obtain genomic inbreeding coefficients. However, there are several methodologies to compute these matrices and there is still an unresolved debate on which one provides the best estimate of inbreeding. In this study, we investigated measures of inbreeding obtained from five genomic matrices, including the Nejati-Javaremi allelic relationship matrix (FNEJ), the Li and Horvitz matrix based on excess of homozygosity (FL&H), and the VanRaden (methods 1, FVR1, and 2, FVR2) and Yang (FYAN) genomic relationship matrices. We derived expectations for each inbreeding coefficient, assuming a single locus model, and used these expectations to explain the patterns of the coefficients that were computed from thousands of single nucleotide polymorphism genotypes in a population of Iberian pigs. Results Except for FNEJ, the evaluated measures of inbreeding do not match with the original definitions of inbreeding coefficient of Wright (correlation) or Malécot (probability). When inbreeding coefficients are interpreted as indicators of variability (heterozygosity) that was gained or lost relative to a base population, both FNEJ and FL&H led to sensible results but this was not the case for FVR1, FVR2 and FYAN. When variability has increased relative to the base, FVR1, FVR2 and FYAN can indicate that it decreased. In fact, based on FYAN, variability is not expected to increase. When variability has decreased, FVR1 and FVR2 can indicate that it has increased. Finally, these three coefficients can indicate that more variability than that present in the base population can be lost, which is also unreasonable. The patterns for these coefficients observed in the pig population were very different, following the derived expectations. As a consequence, the rate of inbreeding depression estimated based on these inbreeding coefficients differed not only in magnitude but also in sign. Conclusions Genomic inbreeding coefficients obtained from the diagonal elements of genomic matrices can lead to inconsistent results in terms of gain and loss of genetic variability and inbreeding depression estimates, and thus to misleading interpretations. Although these matrices have proven to be very efficient in increasing the accuracy of genomic predictions, they do not always provide a useful measure of inbreeding.

11The main objective of this research work was to validate the on site real scale production of 12 dyke blocks employing coarse mixed recycled aggregates, steel slag aggregates and seawater. 13A laboratory experimental phase (Phase 1) was carried out prior to real scale concrete block 14 production within Barcelona's port (Phase 2). According to the results, the concretes 15 produced with a combined mixture of 50% coarse mixed aggregates and 50% of coarse steel 16 aggregates achieved the most adequate properties for use in dyke block manufacturing. The 17 concrete produced employing high percentages of coarse mixed recycled aggregates (without 18 steel slag aggregates) could achieve adequate properties in its saturated state. The use of 19 seawater instead of freshwater reduced the concrete's setting time as well as the porosity of 20 the concretes produced, resulting in both the reduction of water penetration and the capillary 21 water absorption capacity of the concretes. The use of seawater increased concrete's 22 compressive strength at early age. It was also concluded that the results obtained in the 23 laboratory studies and the technical know-how achieved can be transferred to large scale 24 projects. 26 27Keynotes: sustainable concrete; recycled aggregates; steel slags; sea 28 water; concrete block; case study; cores; properties 29 30 31 INTRODUCTION 32The use of recycled aggregates (obtained from the treatment of construction and demolition 33 waste) and steel slag industrial by-products as coarse aggregate in normal concrete mixes is 34 primordial in reducing the environmental problems created by the dumping of these materials, 35 thus helping to maintain sustainability of the environment by reducing the opening of new 36 quarry developments for concrete production. 37 *Manuscript Click here to download Manuscript: manuscript_reviewed_FINAL.docx Click here to view linked References Due to its diverse content, i.e. large amounts of ceramic material and other impurities besides 38 concrete and raw aggregates, the resulting recycled aggregate sourced from the C&DW 39 treatment plants is commonly designated as mixed recycled aggregate (MRA) [1-3]. 40Concretes produced with high percentages of MRA suffer a decrease of density, and 41 mechanical and durability properties with respect to those of conventional concrete [2,[4][5][6][7]. 42However it is well-known that concrete produced with steel slag aggregates achieve a higher 43 density as well as higher mechanical properties than those of conventional concrete [8][9][10]. 44This is due to both their high density and rough surface which results in an effective ITZ [11,45 12]. 46The use of steel slag aggregates together with recycled aggregates can produce better 47 structural concrete [13]. The percentage reduction in compressive strength is greater than that 48 of the flexural strength when recycled concrete aggregates are incorporated. However, the 49 strength reduction in mixes containing slag aggregates is much less resulting in the production 50 of...

One of the main objectives of genetic breeding programs in turbot industry is to reduce disease-related mortality. In the present study, a genome scan to detect quantitative trait loci (QTL) affecting resistance and survival to viral haemorrhagic septicaemia (VHS) was carried out. Three full-sib families with approximately 90 individuals each were genotyped and evaluated by linear regression and maximum likelihood approaches. In addition, a comparison between QTL detected for resistance and survival time to other important bacterial and parasite diseases affecting turbot (furunculosis and scuticociliatosis) was also carried out. Finally, the relationship between QTL affecting resistance/survival time to the virus and growth-related QTL was also evaluated. Several genomic regions controlling resistance and survival time to VHS were detected. Also significant associations between the evaluated traits and genotypes at particular markers were identified, explaining up to 14 % of the phenotypic variance. Several genomic regions controlling general and specific resistance to different diseases in turbot were detected. A preliminary gene mining approach identified candidate genes related to general or specific immunity. This information will be valuable to develop marker-assisted selection programs and to discover candidate genes related to disease resistance to improve turbot production.

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