Modeling the impact of climate change on mussel aquaculture in a coastal upwelling system: A critical assessment

Forecasting of climate change impacts on marine aquaculture production has become a major research task, which requires taking into account the biases and uncertainties arising from ocean climate models in coastal areas, as well as considering culture management strategies. Focusing on the suspended mussel culture in the NW Iberian coastal upwelling system, we simulated current and future mussel growth by means of a multistructural net production Dynamic Energy Budget (DEB) model. We considered two scenarios and three ocean climate models to account for climate uncertainty, and applied a bias correction to the climate models in coastal areas. Our results show that the predicted impact of climate change on mussel growth is low compared with the role of the seeding time. However, the response of mussels varied across climate models, ranging from a minor growth decline to a moderate growth increase. Therefore, this work confirms that an accurate forecasting of climate change impacts on shellfish aquaculture should take into account the variability linked to both management strategies and climate uncertainty

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

Simultaneous determination of dissolved organic carbon and total dissolved nitrogen in seawater by high temperature catalytic oxidation: conditions for precise shipboard measurements

9 páginas, 4 figuras, 1 tablaAppropriate conditions have been achieved for the accurate, rapid, and highly precise shipboard simultaneous determination of dissolved organic carbon and total dissolved nitrogen in seawater by high temperature catalytic oxidation. A nitrogen-specific Antek 705D chemiluminescence detector and a CO2-specific LiCor Li6252 IRGA have been coupled in-series with a Shimadzu TOC-5000 organic carbon analyser. Precision of both simultaneous measurements is F1.5%, i.e. "1 mmol C ly1 and "0.3 mmol N ly1, respectively. Quality of analysis is not compromised by vibrations associated with ocean going research vessels.Support for this work came from the EC MAST-II project OMEX grant No MAS2-CT-93-0069., the UK DoE grant No. PECD 7r8r233 and the NERC Special Topic GSTr01r1355. A postdoctoral fel- lowship from the EC MAST-II programme grant No. MAS2-CT-94-5020. allowed X.A.A.-S. to carry out this work at the Plymouth Marine Laboratory.Peer reviewe

Mineralization of biogenic materials in the water masses of the South Atlantic Ocean. II: Stoichiometric ratios and mineralization rates

International audienceThe variability of nitrate (N), phosphate (P), silicate (Si) and Apparent Oxygen Utilization (AOU) due to water mass mixing was objectively separated from the variability due to mineralization of biogenic materials in the western and eastern South Atlantic Ocean on basis of the constrained Optimum MultiParameter (OMP) analysis implemented in the companion manuscript. Using a consensus linear regression model, AOU/N/P/Si mineralization ratios and the corresponding oxygen utilisation rates (OURs) were obtained for the realm of each water mass defined after the OMP analysis. Combining these results with a stoichiometric model, the organic carbon to nitrogen (C/N) ratios and the biochemical composition (carbohydrates + lipids, proteins and phosphorus compounds) of the mineralized material, were derived. The vertical variability of the AOU/N, AOU/P and AOU/C mineralization ratios pointed to a significant fractionation during the mineralization of sinking organic matter. This fractionation was confirmed by preferential consumption of organic phosphorous compounds and proteins in shallower levels, which produced an increase of the C/N ratio of the mineralised materials of 0.5 +/- 0.2 mol C mol N-1 every 1000 dbar. OURs in the twilight zone decreased quadratically with the C/N molar ratio of the mineralised material and exponentially with pressure (p, in 10(3) dbar) according to the following regression equation: Ln (OUR)=6.2(+/- 1.2)-2.0(+/- 0.7)* Ln (C/N)-0.6(+/- 0.2)* p(r(2)=0.87, p<0.006, n=8). This variability in the rates and stoichiometric ratios of the biogenic material mineralization compromises our capacity to predict the ocean biogeochemistry response to global change, including the CO2 uptake and storage and the corresponding feedback mechanisms

Seasonal and inter-annual variability of net primary production in the NW Iberian margin (1998–2016) in relation to wind stress and sea surface temperature

Seasonal and inter-annual variability of satellite-derived net primary production (NPP) in the NW Iberian margin and its relationship with the offshore Ekman transport (-Qx) and a variety of sea surface temperature (SST) indices have been examined over the period 1998–2016. Seasonality explained about 55% of NPP variability over the shelf and the adjacent ocean. Maximum NPP rates occurred by May in the adjacent ocean, and were delayed until July over the shelf. The excess production (ΔNPP) over the shelf compared to the ocean domain represented 0.45 ± 0.02 g C m−2 d−1 or 37 ± 2% of the total NPP and peaked in August, in between the maximum -Qx and the maximum SST difference between the shelf and the adjacent ocean (ΔSST). During the upwelling season, the inter-annual variability of NPP in the adjacent ocean correlated positively with the spring stratification (SSTstr) and the average -Qx over the upwelling season and ΔNPP correlated inversely with ΔSST. Conversely, during the downwelling season, ΔNPP correlated with the average stratification (SSTdown) over the downwelling season. The rates of change of NPP with the climate-related variables (-Qx, ΔSST, SSTstr, SSTdown), obtained from these regressions, may be used to test the sensitivity of the NW Iberian upwelling productivity to climate change

Ortoghraphical exercises in the didactics of Czech language in the second grade

This dissertation analyses various kinds of the orthographical exercises in the second grade of the primary school. The dissertation focuses on the question of orthography in the theoretical part, after that it focuses on a short view of orthography in the Czech history or its division into lexical, morphological and syntactical orthography. We find here a short description of the orthography and a view of orthographical's effects in the teaching of Czech language in the primary school or meeting with orthographical guides. The goal of the practical part of this dissertation is a deeper typological description of these exercises, we will primarily focus on examples of rewriting, orthographical analysis, refilling and alternating exercises and dictations