Efficacy of standard and low drift nozzles for insecticide applications against Aonidiella aurantii (Maskell) in citrus

Drift is especially critical when spraying fruit, vine and citrus orchards where pesticides are intensively used. In this context, cone low drift nozzles (LDN) intended for spraying tree crops, have been evaluated relating to cone standard nozzles (STN) in laboratory and deciduous fruit orchards (Van de Zande et al. 2012); (Planas et al., 2013)

Macromolecular crowding links ribosomal protein gene dosage to growth rate in Vibrio cholerae

In fast-growing bacteria, the genomic location of ribosomal protein (RP) genes is biased towards the replication origin (oriC). This trait allows optimizing their expression during exponential phase since oriC neighboring regions are in higher dose due to multifork replication. Relocation of s10-spc-α locus (S10), which codes for most of the RP, to ectopic genomic positions shows that its relative distance to the oriC correlates to a reduction on its dosage, its expression, and bacterial growth rate. However, a mechanism linking S10 dosage to cell physiology has still not been determined.We hypothesized that S10 dosage perturbations impact protein synthesis capacity. Strikingly, we observed that in Vibrio cholerae, protein production capacity was independent of S10 position. Deep sequencing revealed that S10 relocation altered chromosomal replication dynamics and genome-wide transcription. Such changes increased as a function of oriC-S10 distance. Since RP constitutes a large proportion of cell mass, lower S10 dosage could lead to changes in macromolecular crowding, impacting cell physiology. Accordingly, cytoplasm fluidity was higher in mutants where S10 is most distant from oriC. In hyperosmotic conditions, when crowding differences are minimized, the growth rate and replication dynamics were highly alleviated in these strains.The genomic location of RP genes ensures its optimal dosage. However, besides of its essential function in translation, their genomic position sustains an optimal macromolecular crowding essential for maximizing growth. Hence, this could be another mechanism coordinating DNA replication to bacterial growth.Fil: Soler Bistue, Alfonso J. C.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Aguilar Pierlé, Sebastián. Institut Pasteur; FranciaFil: Garcia Garcerá, Marc. Institut Pasteur; FranciaFil: Val, Marie Eve. Institut Pasteur; FranciaFil: Sismeiro, Odile. Institut Pasteur; FranciaFil: Varet, Hugo. Institut Pasteur; FranciaFil: Sieira, Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Krin, Evelyne. Institut Pasteur; FranciaFil: Skovgaard, Ole. Roskilde Universitet; DinamarcaFil: Comerci, Diego José. Universidad Nacional de San Martin. Instituto de Investigaciones Biotecnologicas. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Investigaciones Biotecnologicas.; ArgentinaFil: Rocha, Eduardo P. C.. Institut Pasteur; FranciaFil: Mazel, Didier. Institut Pasteur; Franci

An Atlas of the Thioredoxin Fold Class Reveals the Complexity of Function-Enabling Adaptations

The group of proteins that contain a thioredoxin (Trx) fold is huge and diverse. Assessment of the variation in catalytic machinery of Trx fold proteins is essential in providing a foundation for understanding their functional diversity and predicting the function of the many uncharacterized members of the class. The proteins of the Trx fold class retain common features—including variations on a dithiol CxxC active site motif—that lead to delivery of function. We use protein similarity networks to guide an analysis of how structural and sequence motifs track with catalytic function and taxonomic categories for 4,082 representative sequences spanning the known superfamilies of the Trx fold. Domain structure in the fold class is varied and modular, with 2.8% of sequences containing more than one Trx fold domain. Most member proteins are bacterial. The fold class exhibits many modifications to the CxxC active site motif—only 56.8% of proteins have both cysteines, and no functional groupings have absolute conservation of the expected catalytic motif. Only a small fraction of Trx fold sequences have been functionally characterized. This work provides a global view of the complex distribution of domains and catalytic machinery throughout the fold class, showing that each superfamily contains remnants of the CxxC active site. The unifying context provided by this work can guide the comparison of members of different Trx fold superfamilies to gain insight about their structure-function relationships, illustrated here with the thioredoxins and peroxiredoxins

Optimización de un sensor de aromas para la evaluación de la calidad del mosto destinado a vinificación

Control of the raw material has considerable influence on final wine quality. The objective of this work was to develop a sensor capable of assessing grape juice quality in the cellar. Sensor response was compared with conventional chemical analysis using multivariate data techniques. The aroma sensor array is composed of 14 metal oxide sensors (MOS) gas transducers plus a temperature and a relative humidity sensor. This work showed that the sensor could detect rotten flavours in grape juice.El control de la materia prima tiene una gran influencia sobre la calidad final del vino. El objetivo de este trabajo es desarrollar un sensor capaz de estimar la calidad del mosto a la entrada de las bodegas. La respuesta del sensor se ha correlacionado con los resultados de distintos análisis químicos convencionales mediante técnicas de tratamiento estadístico multivariante. El sensor de aromas se compone de 14 sensores de gases tipo MOS (sensores de óxidos metálicos) más uno de temperatura y otro de humedad relativa. El trabajo realizado demuestra que el sensor de aromas representa una herramienta adecuada para detectar la presencia de podredumbres en el mosto

A new mechanised cultural practice to reduce Ceratitis capitata Wied. populations in area-wide IPM

The Mediterranean fruit fly (or medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), affects most of the fruit species grown in temperate and tropical climate regions, causing significant economic damage. One of the classical cultural strategies against this pest is to gather and bury the remaining fruit after harvest, but this is economically unfeasible today. Wood shredders already available in current Spanish groves can be used to grind or crush fruits laying on the soil as an alternative to this practice and to the use of pesticides in area-wide integrated pest management (IPM). With the purpose of evaluating this alternative, the initial step of this study was to perform laboratory tests to assess the efficacy of crushing and grinding as a method for controlling medflies. The results showed that grinding was 78% effective against larval stages, while crushing resulted in a 17% efficacy, leading us to choose the first alternative. As a second step, the operational parameters (type of cutting tool, shaft rotation speed and tractor speed) of the wood shredders were adjusted to efficiently carry out this practice under field conditions. Finally, the effect of the mechanised grinding of fallen fruit on C. capitata populations was evaluated for two consecutive years in commercial citrus orchards. The results showed a significant 27-46% reduction in C. capitata populations the following spring, thus demonstrating that the newly proposed mechanised alternative can be included in the current area-wide IPM of the pest in Spain

Review of anti-islanding techniques in distributed generators

[EN] In this paper a revision about different techniques for islanding detection in distributed generators is presented. On one hand, remote techniques, not integrated in the distributed generators, are discussed. On the other hand, local techniques, integrated in the distributed generator, are described. Furthermore, it is discussed how the local techniques are divided into passive techniques, based on exclusively monitoring some electrical parameters, and active techniques, which intentionally introduce disturbances at the output of the inverter, in order to determine if some parameters are affected.This work was supported by the Spanish Ministry of Science and Innovation under Grants ENE2006-15521-C03-02 and ENE2009-13998-C02-02.Velasco, D.; Trujillo, CL.; Garcerá, G.; Figueres Amorós, E. (2010). Review of anti-islanding techniques in distributed generators. Renewable and Sustainable Energy Reviews. 14(6):1608-1614. https://doi.org/10.1016/j.rser.2010.02.011S1608161414

Modélisation 2D Euler-Lagrange pour le transport et le dépôt de pesticide en verger

International audienceField tests to estimate spray drift are currently standardized but are very complex, time con-suming, expensive and often cannot be compared. Computational fluid dynamics (CFD) is a useful tool to investigate this phenomenon. The airflow generated by the fan of an air-blast sprayer is highly affected by the canopies, which consequently affects the trajectories of spray droplets and has an important influence on drift. Once determined an air flow model in previous work, the subsequent step is to propose a Eulerian-Lagrangian model to predict droplet trajectories, and compare its results with an experimental mass balance in order to assess its validity. Observed differences between experimental and simulation data have been close to the percentage of spray volume that the mass balance reflected as unknown, thus providing encouraging results

Analyse par CFD du comportement de gouttes lors de l'application de pesticide en arboriculture

International audienceDuring the application of pesticides in tree crops with airblast sprayers, part of the volume does not reach the vegetation and is lost through drift, evaporation, runoff, etc. These losses may pose risks to the environment and human health. To improve the application efficiency and reduce losses it is important to know the behaviour of spray droplets. This work proposes to analyze the behaviour of the droplets sprayed for pesticide applications on citrus by means of Computational Fluid Dynamics (CFD). A CFD simulation based on a 2D Eulerian-Lagrangian model was proposed to simulate both the airflow of an airblast sprayer and the wind, besides the individual behaviour of the droplets. At the end of the simulation, model results predict that 44% of the total amount of sprayed volume ended in the target tree of the treatment, 28% in adjacent trees, 20% was deposited on the ground and 8% was lost as atmospheric drift