Carlsberg Ridge and Mid-Atlantic Ridge: Comparison of slow spreading centre analogues

Eighty per cent of all mid-ocean spreading centres are slow. Using a mixture of global bathymetry data and ship-board multibeam echosounder data, we explore the morphology of global mid-ocean ridges and compare two slow spreading analogues: the Carlsberg Ridge in the north-west Indian Ocean between 57°E and 60°E, and the Kane to Atlantis super-segment of the Mid-Atlantic Ridge between 21°N and 31°N. At a global scale, mid-ocean spreading centres show an inverse correlation between segment length and spreading rate with segmentation frequency. Within this context, both the Mid-Atlantic Ridge super-segment and Carlsberg Ridge are similar: spreading at 22 and 26 mm/yr full rates respectively, being devoid of major transform faults, and being segmented by dextral, non-transform, second-order discontinuities. For these and other slow spreading ridges, we show that segmentation frequency varies inversely with flank height and ridge axis depth. Segments on both the Mid-Atlantic Ridge super-segment and Carlsberg Ridge range in aspect ratio (ridge flank height/axis width), depth and symmetry. Segments with high aspect ratios and deeper axial floors often have asymmetric rift flanks and are associated with indicators of lower degrees of melt flux. Segments with low aspect ratios have shallower axial floors, symmetric rift flanks, and evidence of robust melt supply. The relationship between segmentation, spreading rate, ridge depth and morphology, at both a global and local scale, is evidence that rates of melting of the underlying mantle and melt delivery to the crust play a significant role in determining the structure and morphology of slow spreading mid-ocean ridges

Genetic modification of tomato with the tobacco lycopene β-cyclase gene produces high β-carotene and lycopene fruit

Transgenic Solanum lycopersicum plants expressing an additional copy of the lycopene beta-cyclase gene (LCYB) from Nicotiana tabacum, under the control of the Arabidopsis polyubiquitin promoter (UBQ3), have been generated. Expression of LCYB was increased some 10-fold in ripening fruit compared to vegetative tissues. The ripe fruit showed an orange pigmentation, due to increased levels (up to 5-fold) of beta-carotene, with negligible changes to other carotenoids, including lycopene. Phenotypic changes in carotenoids were found in vegetative tissues, but levels of biosynthetically related isoprenoids such as tocopherols, ubiquinone and plastoquinone were barely altered. Transformants showed tolerance to the bleaching herbicide beta-cyclase inhibitor, 2-(4-chlorophenylthio) triethylamine. The phenotype was inherited for at least three generations

Antioxidant compounds and their bioaccessibility in tomato fruit and puree obtained from a DETIOLATED-1 (DET-1) down-regulated genetically modified genotype

[EN] The economic value, the ease of cultivation and processing, and the well-known health-promoting properties of tomato fruit, make the tomato an important target for genetic manipulation to increase its nutritional content. A transgenic variety, down-regulated in the DETIOLATED-1 (DET-1) gene, has been studied in comparison with the parental line, for antioxidant levels in fresh and hot break fruit, as well as the bioaccessibility of antioxidants from puree. Differences in the concentrations of antioxidants between the wild-type and the genetically modified raw tomatoes were confirmed, but antioxidant levels were maintained to a greater extent in the GM puree than in the parent. The bioaccessibility of the compounds, tested using an in vitro digestion model, showed an increase in the genetically modified samplesL. Mora and P. D. Fraser are grateful to the EU-FP7 Marie Curie Intra-European Fellowship scheme (FOOSAF project) for financial resources. P. Talens acknowledges the Universidad Politecnica de Valencia for the financial support of a fellowship at the Centre for Systems and Synthetic Biology, School of Biological Sciences of Royal Holloway, University of London. Addition funds were received from FP6-EU-SOL and FP7 METAPRO projects (to PDF and PMB)Talens Oliag, P.; Mora, L.; Bramley, PM.; Fraser, PD. (2016). Antioxidant compounds and their bioaccessibility in tomato fruit and puree obtained from a DETIOLATED-1 (DET-1) down-regulated genetically modified genotype. Food Chemistry. 213:735-741. https://doi.org/10.1016/j.foodchem.2016.06.079S73574121

La Proteómica como vía para determinar el origen animal de los productos cárnicos

Comunicaciones a congreso

Measurement issues associated with quantitative molecular biology analysis of complex food matrices for the detection of food fraud

A review of measurement issues associated with quantitative molecular analysis of complex food matrices for the detection of food fraud.</p

Formalizing Neurath's ship:Approximate algorithms for online causal learning

Higher-level cognition depends on the ability to learn models of the world. We can characterize this at the computational level as a structure-learning problem with the goal of best identifying the prevailing causal relationships among a set of relata. However, the computational cost of performing exact Bayesian inference over causal models grows rapidly as the number of relata increases. This implies that the cognitive processes underlying causal learning must be substantially approximate. A powerful class of approximations that focuses on the sequential absorption of successive inputs is captured by the Neurath's ship metaphor in philosophy of science, where theory change is cast as a stochastic and gradual process shaped as much by people's limited willingness to abandon their current theory when considering alternatives as by the ground truth they hope to approach. Inspired by this metaphor and by algorithms for approximating Bayesian inference in machine learning, we propose an algorithmic-level model of causal structure learning under which learners represent only a single global hypothesis that they update locally as they gather evidence. We propose a related scheme for understanding how, under these limitations, learners choose informative interventions that manipulate the causal system to help elucidate its workings. We find support for our approach in the analysis of four experiments