Eficacia del fipronil (EXP 60720A) en el control poblacional de Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) en condiciones de laboratorio

En el presente trabajo se ha estudiado la eficacia del fipronil (insecticida perteneciente al grupo de los pirazoles) en el control del trips Frankliniella occidentalis en condiciones de laboratorio con temperatura 27:19° C (D:N) y fotoperíodo 16:8 h (L:O). Para ello se utilizaron discos de hoja de pimiento (Capsicum annuum) de 2,5 cm de diámetro, tratados por inmersión en diferentes concentraciones de fipronil. Como insecticidas de comparación se utilizaron el formetanato y el acrinatrin por ser los insecticidas de uso más frecuente aplicados en España para el control de trips. De los resultados obtenidos se puede afirmar que a igualdad de dosis de materia activa (5 g/Hl), el fipronil resultó ser más eficaz y en un plazo de tiempo más corto que los insecticidas de referencia empleados, necesitándose un tiempo mínimo de 13 h de exposición para obtener un 95 % de mortalidad frente a 588 h y 10.262 h en el caso del formetanato y acrinatrin, respectivamente.Peer reviewe

Energy fluctuations in vibrated and driven granular gases

We investigate the behavior of energy fluctuations in several models of granular gases maintained in a non-equilibrium steady state. In the case of a gas heated from a boundary, the inhomogeneities of the system play a predominant role. Interpreting the total kinetic energy as a sum of independent but not identically distributed random variables, it is possible to compute the probability density function (pdf) of the total energy. Neglecting correlations and using the analytical expression for the inhomogeneous temperature profile obtained from the granular hydrodynamic equations, we recover results which have been previously observed numerically and which had been attributed to the presence of correlations. In order to separate the effects of spatial inhomogeneities from those ascribable to velocity correlations, we have also considered two models of homogeneously thermostated gases: in this framework it is possible to reveal the presence of non-trivial effects due to velocity correlations between particles. Such correlations stem from the inelasticity of collisions. Moreover, the observation that the pdf of the total energy tends to a Gaussian in the large system limit, suggests that they are also due to the finite size of the system.Comment: 13 pages, 10 figure

[Sres. Diputados provinciales que constituyen la Diputacion en Noviembre de 1872]

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

Studies of Mass and Size Effects in Three-Dimensional Vibrofluidized Granular Mixtures

We examine the steady state properties of binary systems of driven inelastic hard spheres. The spheres, which move under the influence of gravity, are contained in a vertical cylinder with a vibrating base. We computed the trajectories of the spheres using an event-driven molecular dynamics algorithm. In the first part of the study, we chose simulation parameters that match those of experiments performed by Wildman and Parker. Various properties computed from the simulation including the density profile, granular temperature and circulation pattern are in good qualitative agreement with the experiments. We then studied the effect of varying the mass ratio and the size ratio independently while holding the other parameters constant. The mass and size ratio are shown to affect the distribution of the energy. The changes in the energy distributions affect the packing fraction and temperature of each component. The temperature of the heavier component has a non-linear dependence on the mass of the lighter component, while the temperature of the lighter component is approximately proportional to its mass. The temperature of both components is inversely dependent on the size of the smaller component.Comment: 14 Pages, 12 Figures, RevTeX

Instability of short arm of acrocentric chromosomes : Lesson from non-acrocentric satellited chromosomes. Report of 24 unrelated cases

Satellited non-acrocentric autosomal chromosomes (ps-qs-chromosomes) are the result of an interchange between sub- or telomeric regions of autosomes and the p arm of acrocentrics. The sequence homology at the rearrangement breakpoints appears to be, among others, the most frequent mechanism generating these variant chromosomes. The unbalanced carriers of this type of translocation may or may not display phenotypic abnormalities. With the aim to understand the causative mechanism, we revised all the ps-qs-chromosomes identified in five medical genetics laboratories, which used the same procedures for karyotype analysis, reporting 24 unrelated cases involving eight chromosomes. In conclusion, we observed three different scenarios: true translocation, benign variant and complex rearrangement. The detection of translocation partners is essential to evaluate possible euchromatic unbalances and to infer their effect on phenotype. Moreover, we emphasize the importance to perform both, molecular and conventional cytogenetics methods, to better understand the behavior of our genome

Generation of the Rubinstein-Taybi syndrome type 2 patient-derived induced pluripotent stem cell line (IAIi001-A) carrying the EP300 exon 23 stop mutation c.3829A > T, p.(Lys1277*)

Rubinstein-Taybi syndrome (RSTS) is a neurodevelopmental disorder characterized by growth retardation, skeletal anomalies and intellectual disability, caused by heterozygous mutation in either the CREBBP (RSTS1) or EP300 (RSTS2) genes. We generated an induced pluripotent stem cell line from an RSTS2 patient's blood mononuclear cells by Sendai virus non integrative reprogramming method. The iPSC line (IAIi001RSTS2-65-A) displayed iPSC morphology, expressed pluripotency markers, possessed trilineage differentiation potential and was stable by karyotyping. Mutation and western blot analyses demonstrated in IAIi001RSTS2-65-A the patient's specific non sense mutation in exon 23 c.3829A > T, p.(Lys 1277*) and showed reduced quantity of wild type p300 protein

Dietary glycemic load and gastric cancer risk in Italy

We investigated gastric cancer risk in relation to dietary glycemic index (GI) and glycemic load (GL), which represent indirect measures of carbohydrate absorption and consequently of dietary insulin demand, in a case-control study conducted in northern Italy between 1997 and 2007, including 230 patients with the incident, histologically confirmed gastric cancer and 547 frequency matched controls, admitted to the same hospitals as cases with acute non-neoplastic conditions. We used conditional logistic regression models, including terms for major recognised gastric cancer risk factors and non-carbohydrate energy intake. The odds ratios (ORs) in the highest vs lowest quintile were 1.9 (95% CI: 1.0–3.3) for GI and 2.5 (95% CI: 1.3–4.9) for GL. Compared with participants reporting low GL and high fruits/vegetables intake, the OR rose across strata of high GL and low fruits/vegetables, to reach 5.0 (95% CI: 2.2–11.5) for those reporting low fruits/vegetables intake and high GL. Our study may help to explain the direct relation observed in several studies between starchy foods and gastric cancer risk

Acylsucrose-Producing Tomato Plants Forces Bemisia tabaci to Shift Its Preferred Settling and Feeding Site

[Background] The whitefly Bemisia tabaci (Genn.) causes dramatic damage to plants by transmitting yield-limiting virus diseases. Previous studies proved that the tomato breeding line ABL 14-8 was resistant to B. tabaci, the vector of tomato yellow leaf curl disease (TYLCD). This resistance is based on the presence of type IV glandular trichomes and acylsucrose production. These trichomes deter settling and probing of B. tabaci in ABL 14-8, which reduces primary and secondary spread of TYLCD.[Methodology/Principal Findings] Whitefly settlement preference was evaluated on the adaxial and abaxial leaf surfaces of nearly-isogenic tomato lines with and without B. tabaci-resistance traits, 'ABL 14-8 and Moneymaker' respectively, under non-choice and free-choice conditions. In addition, the Electrical Penetration Graph technique was used to study probing and feeding activities of B. tabaci on the adaxial and abaxial leaf surfaces of the same genotypes. B. tabaci preferred to settle on the abaxial than on the adaxial surface of 'Moneymaker' leaves, whereas no such preference was observed on ABL 14-8 tomato plants at the ten-leaf growth stage. Furthermore, B. tabaci preferred to feed on the abaxial than on the adaxial leaf surface of 'Moneymarker' susceptible tomato plants as shown by a higher number of sustained phloem feeding ingestion events and a shorter time to reach the phloem. However, B. tabaci standard probing and feeding behavior patterns were altered in ABL 14-8 plants and whiteflies were unable to feed from the phloem and spent more time in non-probing activities when exposed to the abaxial leaf surface.[Conclusions/Significance] The distorted behavior of B. tabaci on ABL 14-8 protects tomato plants from the transmission of phloem-restricted viruses such as Tomato yellow leaf curl virus (TYLCV), and forces whiteflies to feed on the adaxial side of leaves where they feed less efficiently and become more vulnerable to natural enemies. © 2012 Rodriguez-Lopez et al.Ministerio de Ciencia e Innovación Spain (co-financed by FEDER) projects: AGL2007-66760-C02-02/AGR, AGL2007-66399-CO3-02/AGR, and AGL2010-22287-C02-01/AGR, AGL2010-22287-C02-01/AGR Consejería de Innovación y Ciencia, Junta de Andalucía, Spain (co-financed by FEDER-FSE) projects: AGR-214 and AGR-129Peer Reviewe

Pectinmethyesterases Modulate Plant Homogalacturonan Status in Defenses Against the Aphid Myzus persicae.

Because they suck phloem sap and act as vectors for phytopathogenic viruses, aphids pose a threat to crop yields worldwide. Pectic homogalacturonan (HG) has been described as a defensive element for plants during infections with phytopathogens. However, its role during aphid infestation remains unexplored. Using immunofluorescence assays and biochemical approaches, the HG methylesterification status and associated modifying enzymes during the early stage of Arabidopsis thaliana infestation with the green peach aphid Myzus persicae were analyzed. Additionally, the influence of PME activity on aphid settling and feeding behavior was evaluated by free choice assays and the Electrical Penetration Graph technique, respectively. Our results revealed that HG status and HG-modifying enzymes are significantly altered during the early stage of the plant-aphid interaction. Aphid infestation induced a significant increase in total PME activity and methanol emissions, concomitant with a decrease in the degree of HG methylesterification. Conversely, inhibition of PME activity led to a significant decrease in the settling and feeding preference of aphids. Furthermore, we demonstrate that the PME inhibitor AtPMEI13 has a defensive role during aphid infestation, since pmei13 mutants are significantly more susceptible to M. persicae in terms of settling preference, phloem access, and phloem sap drainage