Development of a medium for the culture of agallian leafhopper cells.

Doctor of Philosophy in PIant PathologyDoctorad

Characterization of TrxC, an Atypical Thioredoxin Exclusively Present in Cyanobacteria

Cyanobacteria form a diverse group of oxygenic photosynthetic prokaryotes considered to be the antecessor of plant chloroplast. They contain four different thioredoxins isoforms, three of them corresponding to m, x and y type present in plant chloroplast, while the fourth one (named TrxC) is exclusively found in cyanobacteria. TrxC has a modified active site (WCGLC) instead of the canonical (WCGPC) present in most thioredoxins. We have purified it and assayed its activity but surprisingly TrxC lacked all the classical activities, such as insulin precipitation or activation of the fructose-1,6-bisphosphatase. Mutants lacking trxC or over-expressing it were generated in the model cyanobacterium Synechocystis sp. PCC 6803 and their phenotypes have been analyzed. The ΔtrxC mutant grew at similar rates to WT in all conditions tested although it showed an increased carotenoid content especially under low carbon conditions. Overexpression strains showed reduced growth under the same conditions and accumulated lower amounts of carotenoids. They also showed lower oxygen evolution rates at high light but higher Fv’/Fm’ and Non-photochemical-quenching (NPQ) in dark adapted cells, suggesting a more oxidized plastoquinone pool. All these data suggest that TrxC might have a role in regulating photosynthetic adaptation to low carbon and/or high light conditions.España, MINECO BIO2016-75634-PJunta de Andalucía P12-BIO-1119 , BIO-28

Chemometrics-Based TLC and GC-MS for Small Molecule Analysis: A Practical Guide

Nowadays, thin-layer chromatography (TLC) and gas chromatography/mass spectrometry (GC-MS) instruments can produce more data than even before. At this point, the use of mathematical and statistical tools has provided the key to resolve the information overload. In this chapter, a practical guide is provided for the TLC and GC-MS analysis of short-chain fatty acids (SCFAs), amino acids, and monosaccharides. A methodology for extracting and transforming the chromatographic data to a suitable format for chemometrics is described. Furthermore, a procedure for chemometric analysis based on principal components analysis and clustering analysis is suggested

Fisiología del amarillamiento de la palma africana: informe de consultoría

Palma-Elaeis guineensi

Distribution of the S-matrix in chaotic microwave cavities with direct processes and absorption

We quantify the presence of direct processes in the S-matrix of chaotic microwave cavities with absorption in the one-channel case. To this end the full distribution P_S(S) of the S-matrix, i.e. S=\sqrt{R}e^{i\theta}, is studied in cavities with time-reversal symmetry for different antenna coupling strengths T_a or direct processes. The experimental results are compared with random-matrix calculations and with numerical simulations based on the Heidelberg approach including absorption. The theoretical result is a generalization of the Poisson kernel. The experimental and the numerical distributions are in excellent agreement with random-matrix predictions for all cases.Comment: 4 pages, 4 figure

Natural and anthropogenic factors as taphonomic agents in the differential preservation of paleontological remains from the fossil deposit “Las Llanadas”, Central Cuba

The results of a taphonomic analysis carried out on the vertebrate fossil deposit “Las Llanadas”, Sancti Spíritus, Cuba, are presented. The origin of the deposit is analyzed through features of the accumulated sediments, combined with the geological structure of the study area. The type of fossiliferous deposit represented was determined according to the categorizations proposed for Cuba by several authors. Differential preservation registered, between the recent material and the fossil and subfossil material, was analyzed by considering the mechanisms of taphonomic alteration identified as direct evidence of specific biostratinomic and fossildiagenetic processes to which the extracted remains were subjected. Anthropogenic and natural factors are discussed as responsible for the current accumulation features of the deposit. The historical reconstruction of the paleontological interventions on the site, during the last century, had been an important element to understand the features of the current fossil assemblage