Actividad fungicida/fungistática in vitro del fosfito de manganeso contra hongos patógenos habitantes del suelo con soja

Las pudriciones de raíz y tallo (PRYT) en el cultivo de soja causadas por patógenos habitantes del suelo son enfermedades comúnmente encontradas en campos de soja y son una de las causas más importantes de pérdidas económicas. La sensibilidad micelial de Fusarium virguliforme, Fusarium tucumaniae, Sclerotinia sclerotiorum y Macrophomina phaseolina fue evaluada en medio de cultivo agar papa glucosa (25 mL) suplementado con diferentes concentraciones (µg mL-1) de fosfito de manganeso (PhiMn) diluido en agua (0; 25; 37.5; 50; 100; 200; 300; 400; 500; 800 y 1000). La sensibilidad del crecimiento micelial fue analizada usando análisis de regresión lineal logarítmico. La concentración de PhiMn necesaria para inhibir el 50% del crecimiento micelial (CI50) fue calculada. Los valores de CI50 fueron desde 105 µg mL-1 (Fusarium spp.) hasta 409 µg mL-1 (M. phaseolina). La formación de esclerocios fue completamente inhibida a 500 µg mL-1. Los resultados del presente estudio representan el primer reporte de la acción fungicida/fungistática in vitro del Phi contra los hongos agentes causales de PRYT en el cultivo de soja.Soybean root and stem rots caused by soil-borne pathogens are diseases commonly found in soybean fields, and one of the most important causes of crop losses. In the present study, the mycelial sensitivity of Fusarium virguliforme, F. tucumaniae, Sclerotinia sclerotiorum and Macrophomina phaseolina was evaluated on potato dextrose agar media (25 mL) supplemented with different concentrations of manganese phosphite (MnPhi) diluted in water (0, 25, 37.5, 50, 100, 200, 300, 400, 500, 800 and 1000 µg/mL). Mycelial growth sensitivity was analyzed using logarithmic linear regression analysis. The MnPhi concentration needed to inhibit 50% of the mycelial growth (IC50) ranged from 105 µg/mL (Fusarium spp.) to 409 µg/mL (M. phaseolina). Sclerotia were completely inhibited at 500 µg/mL. The results of our study represent the first report on the direct in vitro fungicidal/fungistatic action of MnPhi against fungi that are causal agents of soil-borne diseases.Fil: Carmona, Marcelo Anibal. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología; ArgentinaFil: Simonetti, Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Biología Aplicada y Alimentos. Cátedra de Microbiología Agrícola; ArgentinaFil: Ravotti, M. E.. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología; ArgentinaFil: Scandiani, María Mercedes. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Luque, A. G.. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Formento, N. A.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Entre Ríos. Estación Experimental Agropecuaria Paraná; ArgentinaFil: Sautua, Francisco. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología; Argentin

Meteorological-Based Predictions of Wheat Head Blight Epidemic in the Southern Argentinean Pampas Region

In Argentina, head blight is a highly risky disease (caused by Fusarium graminearum), although its occurrence is sporadic depending on prevalent environmental variables. These traits stimulated the development of predictive models of head blight occurrence which would help growers in the selection of control strategies. Empirical equations for predicting head blight incidence were developed at Pergamino (33° 56′ S, 60° 30′ W) associating temperature and moisture variables with mean disease data. Recently a new fundamental-empirical approach for estimating Fusarium index (incidence% x severity%/100) was developed using data of Pergamino and Marcos Juarez (32° 41′ S, 62°07′ W). In this study our objective was to validate both approaches at three more southern locations: La Dulce (38° 10′ S, 58° 00′ W), Miramar (38° 00′ S, 57° 33′ W) and Balcarce (37° 45′ S, 58° 18W), for the 2001 crop season. Examining partial and mean deviation values between observed and predicted incidence data, an underestimation especially at La Dulce was assessed. A clear improvement of incidence goodness of fit estimations was obtained decreasing the heat accumulation defining the length of the wheat critical period for infection. Employing this last critical period length for the fundamental-empirical approach led to satisfactory Fusarium index predictions. This study showed that both approaches developed at northern locations of the Pampas region can be portable and useful for predicting disease intensity at more southern locations, making only a few changes.Centro de Investigaciones en Fitopatologí

Nota breve: “Estudio estratigráfico y sedimentológico de las sedimentitas portadoras de los Titanosaurios gigantes del Albiano tardío de Patagonia central, Argentina”

En el sector central de la provincia de Chubut, dentro de la cuenca de Somuncurá- Cañadón Asfalto, se descubrió un importante yacimiento de vertebrados fósiles, que incluyen restos de los titanosaurios más grandes reportados, hasta el momento, en el mundo. En esta contribución se provee un estudio estratigráfico y sedimentológico preliminar con el objeto de precisar la ubicación temporal y estratigráfica del yacimiento, así como comprender los sistemas de acumulación en los que los dinosaurios se desarrollaron. El mismo se encuentra en la sección superior del Miembro Cerro Castaño (Formación Cerro Barcino), próximo al límite con el suprayacente Miembro Las Plumas. Las rocas portadoras son areniscas y areniscas tobáceas que representan facies de planicie de inundación de un sistema fluvial volcaniclástico meandroso

Vector-based word representations for sentiment analysis: a comparative study

New applications of text categorization methods like opinion mining and sentiment analysis, author profiling and plagiarism detection requires more elaborated and effective document representation models than classical Information Retrieval approaches like the Bag of Words representation. In this context, word representation models in general and vector-based word representations in particular have gained increasing interest to overcome or alleviate some of the limitations that Bag of Words-based representations exhibit. In this article, we analyze the use of several vector-based word representations in a sentiment analysis task with movie reviews. Experimental results show the effectiveness of some vector-based word representations in comparison to standard Bag of Words representations. In particular, the Second Order Attributes representation seems to be very robust and effective because independently the classifier used with, the results are good.XIII Workshop Bases de datos y Minería de Datos (WBDMD).Red de Universidades con Carreras en Informática (RedUNCI

Vector-based word representations for sentiment analysis: a comparative study

New applications of text categorization methods like opinion mining and sentiment analysis, author profiling and plagiarism detection requires more elaborated and effective document representation models than classical Information Retrieval approaches like the Bag of Words representation. In this context, word representation models in general and vector-based word representations in particular have gained increasing interest to overcome or alleviate some of the limitations that Bag of Words-based representations exhibit. In this article, we analyze the use of several vector-based word representations in a sentiment analysis task with movie reviews. Experimental results show the effectiveness of some vector-based word representations in comparison to standard Bag of Words representations. In particular, the Second Order Attributes representation seems to be very robust and effective because independently the classifier used with, the results are good.XIII Workshop Bases de datos y Minería de Datos (WBDMD).Red de Universidades con Carreras en Informática (RedUNCI

Clasificador basado en Máquina de Vectores de Soporte Ajustada para Reconocimiento de Peatones en Tráfico Urbano

The need for autonomy and intelligent decision-making in automobile flow is booming. For this purpose there are a number of interesting problems related to recognition of features in urban environments. One of the main relevant aspects in this subject is the recognition of pedestrians, a technology that is expected to save millions of lives avoiding or decreasing the rates of pedestrian run away. In this paper we propose the recognition of pedestrians in urban environments using a classifier based on a Support Vector Machine. We used up to 5000 images from the INRIA database to train the classifier and validate its accuracy through the cross-validation method.La búsqueda de autonomía en desplazamiento automotriz está en auge. En dicha búsqueda existen diversos problemas a resolver; uno de ellos es el reconocimiento de características en ambientes urbanos que permitan a un vehículo tomar decisiones autónomas. Uno de los aspectos más relevantes corresponde al reconocimiento de transeúntes, una tecnología que se espera pueda salvar millones de vidas en accidentes de atropellamientos. En este trabajo de investigación se propone el reconocimiento de transeúntes en ambientes urbanos por medio de un clasificador basado en una Máquina de Vectores de Soporte ajustada; se consideraron hasta 5000 imágenes de la base de datos la INRIA con el fin de entrenar el clasificador y validar su precisión por medio del método de validación cruzada

Actividad fungicida / fungistática in vitro del fosfito de manganeso contra hongos patógenos habitantes del suelo con soja

Carmona, Marcelo Aníbal. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología. Buenos Aires, Argentina.Simonetti, Ester. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Biología Aplicada y Alimentos. Cátedra de Microbiología Agrícola. Buenos Aires, Argentina.Ravotti, Maximiliano Ezequiel. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología. Buenos Aires, Argentina.Scandiani, M. M. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Centro de Referencia de Micología (CEREMIC). Rosario, Argentina.Luque, A. G. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Centro de Referencia de Micología (CEREMIC). Rosario, Argentina.Formento, Angela Norma. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro Regional Buenos Aires Norte. Estación Experimental Agropecuaria Delta del Paraná (EEA Delta del Paraná). Buenos Aires, Argentina.Sautua, Francisco J. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología. Buenos Aires, Argentina.265-269Soybean root and stem rots caused by soil - borne pathogens are diseases commonly found in soybean fields, and one of the most important causes of crop losses. In the present study, the mycelial sensitivity of Fusarium virguliforme, F. tucumaniae, Sclerotinia sclerotiorum and Macrophomina phaseolina was evaluated on potato dextrose agar media (25 mL) supplemented with different concentrations of manganese phosphite (MnPhi) diluted in water (0, 25, 37.5, 50, 100, 200, 300, 400, 500, 800 and 1000 μg/mL). Mycelial growth sensitivity was analyzed using logarithmic linear regression analysis. The MnPhi concentration needed to inhibit 50% of the mycelial growth (IC50) ranged from 105 μg/mL (Fusarium spp.) to 409 μg/mL (M. phaseolina). Sclerotia were completely inhibited at 500 μg/mL. The results of our study represent the first report on the direct in vitro fungicidal/fungistatic action of MnPhi against fungi that are causal agents of soil - borne diseases

Vector-based word representations for sentiment analysis: a comparative study

New applications of text categorization methods like opinion mining and sentiment analysis, author profiling and plagiarism detection requires more elaborated and effective document representation models than classical Information Retrieval approaches like the Bag of Words representation. In this context, word representation models in general and vector-based word representations in particular have gained increasing interest to overcome or alleviate some of the limitations that Bag of Words-based representations exhibit. In this article, we analyze the use of several vector-based word representations in a sentiment analysis task with movie reviews. Experimental results show the effectiveness of some vector-based word representations in comparison to standard Bag of Words representations. In particular, the Second Order Attributes representation seems to be very robust and effective because independently the classifier used with, the results are good.XIII Workshop Bases de datos y Minería de Datos (WBDMD).Red de Universidades con Carreras en Informática (RedUNCI

Comparative Genomics Provides Insights into the Taxonomy of Azoarcus and Reveals Separate Origins of Nif Genes in the Proposed Azoarcus and Aromatoleum Genera

© 2021 by the authors.Among other attributes, the Betaproteobacterial genus Azoarcus has biotechnological importance for plant growth-promotion and remediation of petroleum waste-polluted water and soils. It comprises at least two phylogenetically distinct groups. The “plant-associated” group includes strains that are isolated from the rhizosphere or root interior of the C4 plant Kallar Grass, but also strains from soil and/or water; all are considered to be obligate aerobes and all are diazotrophic. The other group (now partly incorporated into the new genus Aromatoleum) comprises a diverse range of species and strains that live in water or soil that is contaminated with petroleum and/or aromatic compounds; all are facultative or obligate anaerobes. Some are diazotrophs. A comparative genome analysis of 32 genomes from 30 Azoarcus-Aromatoleum strains was performed in order to delineate generic boundaries more precisely than the single gene, 16S rRNA, that has been commonly used in bacterial taxonomy. The origin of diazotrophy in Azoarcus-Aromatoleum was also investigated by comparing full-length sequences of nif genes, and by physiological measurements of nitrogenase activity using the acetylene reduction assay. Based on average nucleotide identity (ANI) and whole genome analyses, three major groups could be discerned: (i) Azoarcus comprising Az. communis, Az. indigens and Az. olearius, and two unnamed species complexes, (ii) Aromatoleum Group 1 comprising Ar. anaerobium, Ar. aromaticum, Ar. bremense, and Ar. buckelii, and (iii) Aromatoleum Group 2 comprising Ar. diolicum, Ar. evansii, Ar. petrolei, Ar. toluclasticum, Ar. tolulyticum, Ar. toluolicum, and Ar. toluvorans. Single strain lineages such as Azoarcus sp. KH32C, Az. pumilus, and Az. taiwanensis were also revealed. Full length sequences of nif-cluster genes revealed two groups of diazotrophs in Azoarcus-Aromatoleum with nif being derived from Dechloromonas in Azoarcus sensu stricto (and two Thauera strains) and from Azospira in Aromatoleum Group 2. Diazotrophy was confirmed in several strains, and for the first time in Az. communis LMG5514, Azoarcus sp. TTM-91 and Ar. toluolicum TT. In terms of ecology, with the exception of a few plant-associated strains in Azoarcus (s.s.), across the group, most strains/species are found in soil and water (often contaminated with petroleum or related aromatic compounds), sewage sludge, and seawater. The possession of nar, nap, nir, nor, and nos genes by most Azoarcus-Aromatoleum strains suggests that they have the potential to derive energy through anaerobic nitrate respiration, so this ability cannot be usefully used as a phenotypic marker to distinguish genera. However, the possession of bzd genes indicating the ability to degrade benzoate anaerobically plus the type of diazotrophy (aerobic vs. anaerobic) could, after confirmation of their functionality, be considered as distinguishing phenotypes in any new generic delineations. The taxonomy of the Azoarcus-Aromatoleum group should be revisited; retaining the generic name Azoarcus for its entirety, or creating additional genera are both possible outcomes.This research was funded by the BBSRC-Newton Fund (grant numbers BB/N013476/1 and BB/N003608/1). MC was funded by grant BIO2016-79736-R from the Ministry of Economy and Competitiveness of Spain.Peer reviewe

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London