Aplicación de compuestos GRAS para el control de la pudrición blanda en frutos de Jaca (Artocarpus heterophyllus L.) causado por Rhizopus stolonifer

Jackfruit is affected by various pathogens in the post-harvest stage, among which is Rhizopus stolonifer, the causal agent of soft rot. To control this pathogen, fungicides are used which damage the environment and affect human health. This situation encourages the search for safe alternatives, among which is chitosan, which has fungicidal characteristics and controls the ripening of various fruits. Also, potassium sorbate is a compound that has traditionally been used to preserve food. In this study, chitosan (Chi) and potassium sorbate (PS) was applied to inhibit the development of R. stolonifer. Determining the mycelial growth, spore germination, sporulation, the severity of the disease, as well as the activity of enzymes involved in the defense of the fruit such as peroxidase (POD) and polyphenoloxidase (PPO). Obtaining a 100% reduction in mycelial growth and spore germination with the 1% Chi-1.0% PS combination. Furthermore, soft rot is not evident when the same treatment was applied to jackfruit, inducing the activity of POD and PPO. The application of chitosan combined with potassium sorbate may be a promising alternative against soft rot in jackfruit.El fruto de yaca es afectado por diversos patógenos en la etapa de postcosecha entre los que se encuentra el hongo Rhizopus stolonifer agente causal de la pudrición blanda. Para el control de este patógeno se utilizan fungicidas que dañan el medio ambiente y afectan la salud humana. Esta situación llevaa buscar alternativas seguras entre las que se encuentra el quitosano, con características fungicidas y control dela maduración en diversos frutos. Asimismo, el sorbato de potasio es un compuesto que se ha utilizado tradicionalmente para conservar alimentos. En este estudio se aplicó quitosano (Chi, por sus siglas en inglés) y sorbato de potasio (PS, por sus siglas en inglés) para inhibir el desarrollo de R. stolonifer. Se determinó el crecimiento micelial, germinación de esporas, esporulación, severidad de la enfermedad, así como la actividad de las enzimas involucradas en la defensa del fruto como la peroxidasa (POD) y la polifenoloxidasa (PPO). El resultado es una reducción al 100% del crecimiento micelial y la germinación de esporas con la combinación 1% Chi-1.0%PS, tampoco se manifestó unapudrición blanda cuando se aplicó el mismo tratamiento en la yaca, con la inducción en la actividad de POD y PPO. La aplicación de quitosano combinado con sorbato de potasio puede ser una alternativa prometedora contra la pudrición blanda en frutos de yaca

Aproximación de volúmenes de agua subterránea disponibles para riego en las cuencas de los ríos Areco y Arrecifes (Buenos Aires)

Fil: Hernández, Mario Alberto. Cátedra de Hidrogeología. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: González, Nilda. Cátedra de Hidrogeología. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Romanazzi, Pablo. Facultad de Ingeniería. Universidad Nacional de La Plata; ArgentinaFil: Trovatto, María Marta. Cátedra de Hidrogeología. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Solero, Claudia. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Ceci, Horacio. Hidroar SA. 67 No 1747 La Plata. Buenos Aires; ArgentinaFil: Alvarez, María del Pilar. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; Argentin

Catalytic activities of heterogeneous catalysts obtained by copolymerization of metal-containing 2-(acetoacetoxy)ethyl methacrylate

AbstractAmong the synthetic strategies commonly used for supporting a metal complex onto an organic polymer in order to obtain an heterogenous catalyst, a valid choice is to synthesize a metal containing monomer (MCM), which can subsequently be subjected to polymerization with suitable comonomers and crosslinkers, achieving a supported transition metal catalyst as a metal-containing polymer (MCP). In this context, during the last two decades, we explored the use of 2-(acetoacetoxy)ethyl methacrylate (HAAEMA) as a ligand to prepare several MCMs for the relevant MCPs. In this review we summarize and discuss our developments in the studies of the catalytic activity of these "hybrid" catalysts. These catalysts have demonstrated high efficiency and/or excellent selectivity in several kinds of chemical reactions and very often they could be recovered and reused in multiple cycles maintaining their activity and selectivity without suffering from appreciable metal leaching

Aproximación de volúmenes de agua subterránea disponibles para riego en las cuencas de los ríos Areco y Arrecifes (Buenos Aires)

Son presentados resultados de un estudio hidrogeológico aplicado a evaluar agua subterránea pa ra riego, en dos importantes cuencas del Noreste bonaerense (Areco y Arrecifes, 15400 km2), donde se practica agricultura extensiva. La metodología recurrió a tres criterios coalescentes: resolución de un balance hídrico para aproximar la infiltración potencial probable, cálculo de reservas y fijación de un caudal de explotación sustentable. Para el primero se utilizaron datos de las estaciones climatológicas Pergamino, Junín, Rosario y Buenos Aires, con suficiente garantía, representatividad y extensión, estimándose una recarga potencial máxima de 1324 hm3. El cálculo de reservas se realizó para los acuíferos Pampeano y Puelche, con empleo de mapas isopáquicos, isopiécicos, de altura potenciométrica sobre techo del Puelche y coeficientes de porosidad efectiva y almacenamiento. Se calculó un total de 82036 hm3 para el Pampeano (8116 hm3 sustentables) y 48695 hm3 y 5452 hm3 para el Puelche, respectivamente.This paper presents the results of a hydrogeological survey to evaluate groundwater for irrigation in two important basins of northeastern Buenos Aires Province (Areco and Arrecifes, 15400 km2) where extensive agriculture is conducted. Three converging criteria were applied: resolution of a water balance to estimate probable potential infiltration, calculation of reserves and determination of sustainable exploitation yield. The balance was made based on data from the climatological stations Pergamino, Junín, Rosario and Buenos Aires, which have sufficient guarantee, representativeness and extension. The maximum potential recharge was estimated at 1324 hm3. Reserves of the Pampeano and Puelche aquifers were calculated using groundwater isopach, isopiestic and potentiometric head maps at the top of the Puelche aquifer, as well as coefficients of effective porosity and storage. Total and sustainable reserves calculated were 82036 and 8116 hm3 for the Pampean aquifer and 48695 and 5516 hm3 for the Puelche aquifer, respectively.Universidad Nacional de La Plat

Abdominal aortic aneurysm is associated with a variant in low-density lipoprotein receptor-related protein 1

Abdominal aortic aneurysm (AAA) is a common cause of morbidity and mortality and has a significant heritability. We carried out a genome-wide association discovery study of 1866 patients with AAA and 5435 controls and replication of promising signals (lead SNP with a p value < 1 × 10-5) in 2871 additional cases and 32,687 controls and performed further follow-up in 1491 AAA and 11,060 controls. In the discovery study, nine loci demonstrated association with AAA (p < 1 × 10-5). In the replication sample, the lead SNP at one of these loci, rs1466535, located within intron 1 of low-density-lipoprotein receptor-related protein 1 (LRP1) demonstrated significant association (p = 0.0042). We confirmed the association of rs1466535 and AAA in our follow-up study (p = 0.035). In a combined analysis (6228 AAA and 49182 controls), rs1466535 had a consistent effect size and direction in all sample sets (combined p = 4.52 × 10-10, odds ratio 1.15 [1.10-1.21]). No associations were seen for either rs1466535 or the 12q13.3 locus in independent association studies of coronary artery disease, blood pressure, diabetes, or hyperlipidaemia, suggesting that this locus is specific to AAA. Gene-expression studies demonstrated a trend toward increased LRP1 expression for the rs1466535 CC genotype in arterial tissues; there was a significant (p = 0.029) 1.19-fold (1.04-1.36) increase in LRP1 expression in CC homozygotes compared to TT homozygotes in aortic adventitia. Functional studies demonstrated that rs1466535 might alter a SREBP-1 binding site and influence enhancer activity at the locus. In conclusion, this study has identified a biologically plausible genetic variant associated specifically with AAA, and we suggest that this variant has a possible functional role in LRP1 expression

Influence function of halfspace depth

AbstractThe sensitivity of halfspace depth values and contours to perturbations of the underlying distribution is investigated. The influence function of the halfspace depth of any point x∈Rp is bounded and discontinuous; it is constant and positive when the perturbing observation z is placed in any optimal halfspace and it is constant and negative when z is placed in any non-optimal halfspace. When the optimal halfspace is unique a von Mises expansion allows an easy derivation of the asymptotic distribution of the sample halfspace depth. In the sampling case, in general, addition of a single observation outside the convex hull of the sample alters all the depth regions but only the outer region can be arbitrarily expanded. To obtain the same effect on the inner regions the size of the perturbation is required to be not less than the depth orders. Numerical illustrations of the results are given

Influence Function of Halfspace Depth

The sensitivity of halfspace depth values and contours to perturbations of the underlying distribution is investigated. The influence function of the halfspace depth of any point x[set membership, variant]p is bounded and discontinuous; it is constant and positive when the perturbing observation z is placed in any optimal halfspace and it is constant and negative when z is placed in any non-optimal halfspace. When the optimal halfspace is unique a von Mises expansion allows an easy derivation of the asymptotic distribution of the sample halfspace depth. In the sampling case, in general, addition of a single observation outside the convex hull of the sample alters all the depth regions but only the outer region can be arbitrarily expanded. To obtain the same effect on the inner regions the size of the perturbation is required to be not less than the depth orders. Numerical illustrations of the results are given.halfspace depth halfspace region influence function simplicial depth