Estimating aerial biomass of six woody Leguminosae of the Arid Chaco (Argentina)

La posibilidad de contar con estimaciones confiables de la biomasa aérea de la vegetación leñosa resulta imprescindible para el manejo productivo, la conservación o la restauración de los ecosistemas de bosque. Sin embargo, no siempre se dispone de técnicas relativamente sencillas y no destructivas. Este trabajo presenta modelos de regresión para estimar la biomasa aérea total de seis especies arbustivas y arbóreas de la familia Fabaceae, nativas del Chaco Árido (Prosopis flexuosa, Geoffroea decorticans, Cercidium praecox, Acacia furcatispina, Mimoziganthus carinatus y Prosopis torquata). Los modelos incluyeron distintas combinaciones del diámetro a la base (DAB) y la altura de los individuos. Todos ellos predijeron aceptablemente la biomasa por especie, si bien el de regresión lineal que utiliza el DAB2 como variable independiente presentó el mejor ajuste. Las especies fueron agrupadas según sus rasgos comunes en: monopódicas de madera dura, multitallares de madera extremadamente pesada, monopódica de madera excesivamente pesada y monopódica y multitallar de madera extremadamente pesada y para cada uno de los grupos se generó una ecuación.Reliable estimates of biomass forthe vegetation of the Arid Chaco forest is critical for its management, conservation or restoration. However, simple and non destructive techniques are not largely available. This study provides regression models aimed at estimating the aerial biomass of native shrub and tree species from the Arid Chaco, belonging to the Fabaceae family (Prosopis flexuosa, Geoffroea decorticans, Cercidium praecox, Acacia furcatispina, Mimoziganthus carinatus and Prosopis torquata). An additional objective was to explore the feasibility of using a single equation for several species. The wood density differed significantly between species. Linear and nonlinear regression models of aerial biomass were adjusted for species, with different combinations of base diameter (DAB) and height as independent variables. The models properly predicted the biomass by species, the most appropriate being the linear regression model using DAB2 as an independent variable. To establish differences in the behavior of species and, more precisely, in the ratio between total dry weight and DAB, the slope homogeneity was analyzed using a regression model with auxiliary variables. Taking into account the results obtained and the basic wood density and morphological growth structure, four groups of species have been postulated, and it was feasible to apply a single equation per group. The proposed groups are: (1) monopodial hardwood (Geoffroea decorticans and Cercidium praecox), (2) multi-stem shrubs of extremely heavy wood (Acacia furcatispina and Mimoziganthus carinatus), (3) monopodial of very heavy wood (Prosopis flexuosa) and (4) monopodial and multi-stem of extremely heavy wood (Prosopis torquata).Fil: Iglesias, María del Rosario. Universidad Nacional de Córdoba. Facultad de Cs.agropecuarias. Cátedra de Ecología Agrícola; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Barchuk, Alicia Haydee. Universidad Nacional de Córdoba. Facultad de Cs.agropecuarias. Cátedra de Ecología Agrícola; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Estimación de evapotranspiración real en trigo con distintas condiciones de estrés hídrico: aplicación de modelos y sensores remotos

Tesis (Magister en Aplicaciones Espaciales de Alerta y Respuesta Temprana a Emergencias)--Universidad Nacional de Córdoba, Facultad de Matemática, Astronomía y Física, 2016.Maestría conjunta con el Instituto de Altos Estudios Espaciales "Mario Gulich"-CONAEEl objetivo principal de esta tesis es estimar la evapotranspiración real de un cultivo de trigo, mediante modelos semiempírico, que incorporan datos de sensores remotos y de sensores meteorológicos a campo. También, se corroboró la relación entre índices de vegetación y la evapotranspiración. Por último, se comprobó el desempeño de un simulador de cultivo en la estimación diaria de ET. Ambos modelos (semiempírico y simulador), se verificaron sus ajustes mediante datos de evapotranspiración de una torre de flujo in situ (eddy covariance). Los resultados de esta tesis brindan un modelo semiempírico para ser aplicados en la estimación de evapotranspiración real en cultivos de trigo.The main objective of this thesis was to estimate actual crop evapotranspiration of wheat, by semi-empirical model that incorporate remote sensing data and meteorological field sensors. Also, this thesis paper explores the relationship between difference vegetation index and evapotranspiration and the performance of daily crop simulation of DSSAT software's model. Both models adjustment (semi-empirical and DSSAT simulation), were verified with in situ-based estimates of evapotranspiration by Eddy covariance tower. The results of this thesis provide a semi-empirical model with high setting, to be applied in the estimation of actual evapotranspiration in wheat crops

Controversy about the Spanish court in Luis Vélez de Guevara’s short plays: playwright and literary subject

Las miserias del cortesano, la queja del servidor o la petición de mercedes están presentes en una amplia nómina de autores áureos que retratan la corte como un ambiente tóxico, en una continua querella que pone en evidencia las penurias de su vivir diario, del hambre y de otras desventuras de este mundo, propiciadas sobre todo por la codicia y la ambición. Este topos literario ya tenía eco en la Antigüedad Clásica, pero para el trabajo que nos ocupa interesa su desarrollo en la literatura anticortesana del siglo XVII, al ser la etapa en la que vivió el dramaturgo Luis Vélez de Guevara (1579-1644). El teatro barroco tuvo un interesante componente de crítica, al ser considerado un poderoso vehículo de transmisión de ideas y, por ello, resultaría un medio idóneo para denunciar esta situación que pudo, con gran probabilidad, recoger las experiencias personales y, por consiguiente, la verdadera cara de la corte.The courtier’s misery, the servant’s complaint or the petition of favours are present in a wide list of Golden Age authors that portray the court as a toxic environment, in a continuous quarrel that evinces the dearths of daily life, hunger and other misadventures of this world, mainly promoted by greed and ambition. This literary motif already echoed in Classical Antiquity, but, for the research that concerns us, we will focus on its development in 17th century anti-courtly literature, since it was the period when the playwright Luis Vélez de Guevara (1579-1644) lived. The Baroque theater had an interesting component of criticism, as it was considered a powerful tool for the transmission of ideas and, therefore, it would be an ideal way to denounce this situation that they could, most probably, personally live and, consequently, report the real face of the court.Ministerio de Ciencia, Innovación y Universidades RTI2018-095664-B-C2

Antiviral activity of ribosome-inactivating proteins

Producción CientíficaRibosome-inactivating proteins (RIPs) are rRNA N-glycosylases from plants (EC 3.2.2.22) that inactivate ribosomes thus inhibiting protein synthesis. The antiviral properties of RIPs have been investigated for more than four decades. However, interest in these proteins is rising due to the emergence of infectious diseases caused by new viruses and the difficulty in treating viral infections. On the other hand, there is a growing need to control crop diseases without resorting to the use of phytosanitary products which are very harmful to the environment and in this respect, RIPs have been shown as a promising tool that can be used to obtain transgenic plants resistant to viruses. The way in which RIPs exert their antiviral effect continues to be the subject of intense research and several mechanisms of action have been proposed. The purpose of this review is to examine the research studies that deal with this matter, placing special emphasis on the most recent findings.Junta de Castilla y León - (Grant VA033G19

Basal resprout of Aspidosperma quebracho blanco in state of seedling : persistence mechanism in the Arid Chaco

La estrategia de rebrote contribuye fuertemente a la supervivencia de especies leñosas bajo condiciones de estrés y disturbios. En este trabajo se evaluó el impacto de la remoción de la biomasa aérea sobre la capacidad rebrotar desde el hipocótilo y el cuello de la raíz de plántulas de A. quebracho-blanco. En invernáculo, sobre plántulas de 9 meses de edad, fueron aplicados dos tratamientos: remoción total (por debajo del nudo cotiledonal y sin yemas axilares) y parcial de la biomasa aérea (por encima del nudo cotiledonal, con yemas axilares y presencia de cotiledones). A campo, en un bosque de A. quebracho blanco del Chaco Árido, se aplicó sobre plántulas de 2 años, la remoción total de la biomasa por debajo del nudo cotiledonal. En ambos experimentos se evaluaron supervivencia y variables estimadoras del crecimiento a los 10 meses y al año de aplicadas las remociones, respectivamente. Los datos de supervivencia fueron examinados utilizando Modelos Lineales Generalizados. Se aplicó ANCOVA para medidas repetidas en el tiempo con variables de crecimiento. Los resultados mostraron que las plántulas son capaces de rebrotar desde yemas adventicias formadas en el hipocótilo y el cuello de la raíz (siempre por debajo del nudo cotiledonal) después de una perturbación severa que deja a la plántula sin yemas de crecimiento. La importancia de este tipo de rebrote se incrementa notablemente con la edad de la plántula y se relaciona con el estímulo del corte. Desde el punto de vista sucesional, el rebrote puede favorecer el auto-reemplazo de la especie ya que confiere por largo tiempo una persistencia in situ de los juveniles y retrasa la muerte de estos en un ambiente donde los recursos son muy limitados.Resprouting strategy strongly contributes to survival of woody species, which can survive under stress and disturbance conditions, such as logging, herbivory and fire. The capacity of plants to resprout from adventitious buds at seedling stage, a highly vulnerable plant stage, may be determinant in the establishment success of species in arid environments. In this work, the effect of aereal biomass removal on the capacity of seedlings of A. quebracho blanco to resprout from the hypocotyl and root neck was evaluated. Two treatments were applied in 9-month-old seedlings in greenhouse: total removal (below the cotyledon junction and without axillary buds), and partial removal of aereal biomass (above cotyledon junction, with axillary buds and presence of cotyledons). In the field, in a forest of A. quebracho blanco of the Arid Chaco, total biomas below cotyledonal junction was removed in two-year-old seedlings. In both experiments, survival and growth-estimating variables at 10 months and 1 year after removal, respectively, were evaluated. Greenhouse data were evaluated by ANCOVA for measures repeated in time; field data were analyzed using Generalized Linear Models. Results showed that seedlings can easily resprout from hypocotyl and root neck after severe disturbance. The importance of resprouting increases considerably with seedling age and is related to adventitious buds formed below the removed cotyledon junction. The data suggest that no preformed buds would occur below the cotyledon junction, but that they would be formed by the stimulus provided by the cut. Thus, this species might persist as a seedling bank in environments with water deficit because of the differentiation of adventitious buds

Range overlap between the sword-billed hummingbird and its guild of long-flowered species: An approach to the study of a coevolutionary mosaic

The coevolutionary process among free-living mutualists with extremely long matching traits may favor the formation of mutualistic interaction networks through coevolutionary escalation, complementarity and convergence. These networks may be geographically structured; the links among the species of a local network are shaped by the biotic composition of the community, thus creating selection mosaics at broader geographical scales. Therefore, to fully understand a coevolutionary process, it is crucial to visualize the geographical structure of the interaction network across the landscape. In this study we focused on the poorly known interaction system between Ensifera ensifera and its guild of long-flowered plant species. We combined occurrence data and environmental variables to predict E. ensifera distribution, in addition to range polygons available for plant species in order to evaluate the geographical variation in bill length and plant species richness. A positive relationship between bill length and plant species richness within the E. ensifera range suggests a geographical structuring of the interaction networks. At mid-latitude locations of E. ensifera range, where hummingbirds attained the longest bills, richness of long-flowered plant species was higher than at low latitude locations. These locations likely represent coevolutionary vortices where long-lasting reciprocal selection probably drove the evolution of long traits, consequently drawing new plant species into the coevolutionary network. Conversely, areas where the sword-billed hummingbird was absent or had shorter bills probably represent coevolutionary coldspots. Our results provide a first insight into this phenotypically specialized plant-pollinator network across the landscape and show candidate areas to test the predictions of the coevolutionary hypothesis, such as reciprocal selection.Fil: Soteras, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Moré, Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Ibañez, Ana Clara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Iglesias, María del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Cocucci, Andrea Aristides. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

Killing cancer cells by targeting the EGF receptor

Producción CientíficaIn this issue of Cancer Biology & Therapy, Bachran et al. analyze the effect of two chimeric toxins (SE and SA2E) consisting of the epidermal growth factor (EGF) and the plant protein toxin saporin towards an oral squamous cell carcinoma cell line (BHY) as well as on primary oral squamous cell carcinoma (OSCC) tumour cells

The lowland seasonally dry subtropical forests in central Argentina: vegetation types and a call for conservation

The native woody vegetation from the Espinal phytogeographic province in central Argentina, found in subtropical-warm temperate climates, represents part of the southernmost seasonally dry forest in South America. Although this vegetation has been studied for over a century, a complete phytosociological survey is still needed. This lack of knowledge makes its spatial delimitation and the establishment of efficient conservation strategies particularly difficult. The main goals of this study were to classify these forests and assess their current forest cover and to better define the extent of the Espinal phytogeographic province in Córdoba region, central Argentina. Study area: Espinal Phytogeographic Province in Córdoba region, central Argentina (ca. 101,500 km2). Methods: We sampled 122 stands following the principles of the Zürich-Montpellier School of phytosociology; relevés were classified through the ISOPAM hierarchical analysis. The extent of the Espinal phytogeographic province was established by overlaying previous vegetation maps, and a map showing the current distribution of forest patches was constructed based on a supervised classification of Landsat images. Results: Four woody vegetation types of seasonally dry subtropical forest were identified based on the fidelity and the abundance of diagnostic species: (1) Aspidosperma quebracho-blanco forest; (2) Zanthoxylum coco forest; (3) Geoffroea decorticans forest; and (4) Prosopis caldenia forest. These vegetation types were segregated along gradients of temperature and precipitation seasonality and soil-texture and sodium content. The remaining forest patches represent 3.43% of the extent of the Espinal province in Córdoba region of which only 1.05% is represented in protected areas. Conclusions: We present a classification of the Espinal forest based on a complete floristic survey. Despite the dramatic forest loss reported, our results show that some forest patches representative of the Espinal are still likely to be found in the area. However, urgent measures should be taken to establish new protected natural areas in order to preserve the last remaining forest patches.Taxonomic reference: Catálogo de las Plantas Vasculares del Cono Sur (Zuloaga et al. 2008) and its online update (http://www.darwin.edu.ar).Abbreviations: ISOMAP = isometric feature mapping; ISOPAM = isometric partitioning around medoids.Keywordscentral Argentina, chorotype, diagnostic species, dry subtropical forest, Espinal phytogeographic province, exotic spFil: Zeballos, Sebastián Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Giorgis, Melisa Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Cabido, Marcelo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Acosta, Alicia Teresa Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Università degli Studi di Roma Tre; ItaliaFil: Iglesias, María del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Cantero, Juan Jose. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

Prevalence of Human Intestinal Entamoeba spp. in the Americas: A Systematic Review and Meta-Analysis, 1990–2022

Among the seven species of Entamoeba known to infect humans, E. histolytica is widely recognized as a pathogen. It is reported that Entamoeba infections are common in the developing world, but rare in developed countries. The best way to diagnose these protozoan parasites is to detect antigens or DNA in the stool. This study aimed to review the prevalence, distribution, and diagnosis methods of Entamoeba spp. infecting humans in the Americas between 1990 and 2022. A systematic review and meta-analysis were performed, including 227 studies on Entamoeba infections from 30 out of 35 American countries. The pooled prevalence of each species of Entamoeba was calculated using the random-effects model. The assignment of Entamoeba species was mainly performed by microscopy. The most widely distributed and prevalent species was E. coli (21.0%). Of the studies, 49% could not differentiate the species of the Entamoeba complex. The pathogenic species E. histolytica was distributed among 22 out of 30 American countries studied, with a pooled prevalence of 9%. Molecular data on Entamoeba species are still scarce. This is the first study that reviewed and summarized data on the prevalence of this protozoan genera among American countries.Fil: Servian, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Helman, María Elisa. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Epizootiología y Salud Pública. Laboratorio de Inmunoparasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Iglesias, María del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Panti May, Jesús Alonso. Universidad Autonoma de Yucatan (uady);Fil: Zonta, Maria Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Navone, Graciela Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentin

La sostenibilidad de los desequilibrios en las balanzas por cuenta corriente de la eurozona

En este trabajo estudiamos los factores que determinan la sostenibilidad de los déficits por cuenta corriente en la eurozona y su vinculación con la crisis. Para ello, estimamos las ecuaciones de comercio exterior, donde se confirma el papel determinante de la elasticidad-renta, y, posteriormente, estimamos el crecimiento económico restringido por la balanza de pagos (Thirlwall) para compararlo con el crecimiento efectivo de cada país. Únicamente España, Gre-cia y Portugal mantuvieron, entre 2000 y 2007, crecimientos superiores a los consistentes con la restricción exterior. Aunque no sostenibles, sus déficits son diferentes ya que tienen raíz estructural en Grecia y Portugal