Argentinean pejerrey (Odonthestes bonariensis) : artificial feeding

Para comprobar la factibilidad de la alimentación artificial del pejerrey con pienso balanceado pelletizado y aproximar el porcentaje de proteína en la formulación se realizó un ensayo con cuatro tratamientos: testigo (T) sin alimento artificial, alimento de 24 % (P1), 32 % (P2) y 42 % de proteína (P3). Para ello se realizaron cuatro jaulas de 4x4 m, ubicadas en una represa de la zona de Tunuyán, provincia de Mendoza. En cada jaula se colocaron 100 pejerreyes de un peso medio de 64,8 gramos. Luego de tres me-ses de encierre y diez días de adaptación a la dieta, se alimentaron P1, P2 y P3 con una ración de 1 g por pez/día en 40 días. Los peces de estas parcelas aumentaron un pro-medio de 7,7 g/pez.día 40 días, mientras que los testigos bajaron 7,9 g/por pez en el mis-mo período. Dividiendo a los peces en categorías se pudo determinar que los de mayor tamaño crecían más. Los peces con pesos iniciales medios de 83,5; 60,3 y 47,8 g lograron un aumento de peso medio promedio respectivamente de 8,4; 2,6 y -3,2 g, con un máximo de aumento de 17,8 g en el caso de P1 y con pejerreyes de 78,3 g de peso. No se pudo realizar repeticiones ni prueba estadística debido a la mortandad producida por pájaros pescadores. Se puede afirmar que los pejerreyes toleran el encierro (7,8 peces/m3) y el manejo y aceptan los alimentos balanceados pelletizados, sobre todo los peces de peso vivo superior a 60 g.W ith the p urpo se o f verifyin g th e factibility of artificial feeding of «pejerrey» with balanced pelletized feed and approximating protein percentage in the feed formula, a trial was carried out with four treatments: control (T) without artificial feed, 24 % (P1), 32 % (P2), 42 % (P3) protein feed. Four 4x4 m cages were made and placed in a dam of Tunuyan zone in the province of Mendoza. One hundred pejerreyes 64,8 average weight was placed in each cage, and after a three month confinement adaptation period, and ten days of balanced diet, three lots were fed with a ration of 1 g/day/fish. These fishes gained an average weight of 7.7g/day in 40 days while the control group lost 7.9 g per fish in the same period. The fishes were classified according to weight. It could be reached the conclusion that heavier fishes grew up more. Initial 83.5; 60.3 and 47.8 average weight fishes gained 8.4, 2.6 and -3.2 g weight respectively, with a maximum of weigh t gain o f 17 .8 g in 7 8.3g weigh t pejerreyes of P1. Neither repetitions nor statistical analysis could be done because of the high mortality due to fishing birds. The pejerreyes tolerated confinement (7,8 fishes/m3) and handling well and accepted the arti-ficial feed.Fil: Tacchini, Fabio M. . Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Producción AgropecuariaFil: Allende, Gabriel M. . Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Producción AgropecuariaFil: Linares, Christian D. . Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Producción AgropecuariaFil: Martínez, Gustavo M. . Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Producción Agropecuari

Preyssler Heteropolyacids in the Self-Etherification of 5-Hydroxymethylfurfural to 5,5′-[Oxybis(methylene)]bis-2-furfural Under Mild Reaction Conditions

The synthesis of 5,5′-[oxybis(methylene)]bis-2-furfural (OBMF) from 5-hydroxymethylfurfural (5-HMF) was studied using bulk and alumina-supported Preyssler heteropolyacids (HPAs). The formation of OBMF was related to the amount of Brønsted acid sites, and the lowest yield of OBMF was obtained with supported HPAs. However, the Lewis acidity of the HPA supported on Al2O3 favored the formation of 2,5-dimethylfurane. The effects of solvent, catalyst loading, temperature, and reaction time on the selectivity to OBMF from 5-HMF were studied to optimize OBMF production using bulk Preyssler HPAs; a yield of 84 % to OBMF was obtained at 5 h and 343 K. These results demonstrate that bulk Preyssler HPA is a good candidate for OBMF synthesis under mild reaction conditions.Fil: Páez, Alexander. Universidad Pedagógica y Tecnológica de Colombia; ColombiaFil: Rojas, Hugo A.. Universidad Pedagógica y Tecnológica de Colombia;Fil: Portilla Zúñiga, Omar Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Sathicq, Angel Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Afonso, Carlos A. M.. Universidade de Lisboa; PortugalFil: Romanelli, Gustavo Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Martínez, José J.. Universidad Pedagógica y Tecnológica de Colombia; Colombi

Evaluación de cinco genotipos promisorios de papa solanum tuberosum sp. andigena según desempeño agronómico y calidad industrial

Con base en variables cualitativas y cuantitativas se llevó a cabo la evaluación de cinco genotipos promisorios de papa Solanum tuberosum sp. andigena pertenecientes a la Corporación Colombiana de Investigación Agropecuaria –CORPOICA– y de la variedad Diacol Capiro, en siete localidades del país. Los resultados se analizaron por métodos univariados y multivariados para conocer las características que discriminaban a los materiales. En el análisis multivariado de componentes principales, los primeros cuatro componentes representan el 95,22% de la variación total. Las variables de mayor influencia fueron época de maduración, época de emergencia, peso total de los tubérculos por parcela, peso de los tubérculos de tamaño primera, peso de los tubérculos de tamaño cero, peso de los tubérculos de tamaño cuarta, gravedad específica y materia seca. Se detectó que existe interacción significativa entre genotipo y ambiente para las variables de rendimiento en frito y calidad industrial, las cuales, según el análisis de estabilidad fenotípica de Kang (1991), permitieron seleccionar los clones 2, 7 y 14 como los más rendidores y estables según las características peso total de los tubérculos por parcela, materia seca y rendimiento en frito. Considerando el índice de rendimiento y la estabilidad fenotípica combinadas, el clon 7 se recomienda como el material más promisorio

Identification of the variability of a common bean collection through morphological, physiological, biochemical, and molecular relationships

The present study was carried out in Corpoica, C.I. Tibaitata (Mosquera, Colombia) at an altitude of 2,540 m a.s.l. in six environments composed of different seasons and at an altitude of 1,485 m a.s.l. in the International Center of Tropical Agriculture (CIAT), Calima, Colombia. Morphological, physiological, biochemical, and molecular descriptors were used to estimate the genetic variability between 36 Colombian bean accessions, of which four were wild and the others cultivated. Diacol Calima (Nueva Granada from the Andean gene pool) and ICA Pijao (Mesoamerican from the mesoamerican gene pool) were used as controls. The combined analysis of the qualitative and quantitative variables was carried out with Gower distance and an unified data matrix with 315 descriptors. The relationships between the genetic distances differentiated the bean collection into two genetic groups: Andean and Mesoamerican. The following groups of characteristics presented high association: total morphology with qualitative morphology (P=0.91), physiological evaluation with grouped evaluation of morphological, quantitative, and physiological characteristics (P=0.91), characterization of isoenzymatic and molecular markers with respect to just molecular markers (P=0.99) and the characterization of all the studied markers in relation to the molecular and isoenzymatic markers (P=0.88)

Identification of the variability of a common bean collection through morphological, physiological, biochemical, and molecular relationships

The present study was carried out in Corpoica, C.I. Tibaitata (Mosquera, Colombia) at an altitude of 2,540 m a.s.l. in six environments composed of different seasons and at an altitude of 1,485 m a.s.l. in the International Center of Tropical Agriculture (CIAT), Calima, Colombia. Morphological, physiological, biochemical, and molecular descriptors were used to estimate the genetic variability between 36 Colombian bean accessions, of which four were wild and the others cultivated. Diacol Calima (Nueva Granada from the Andean gene pool) and ICA Pijao (Mesoamerican from the mesoamerican gene pool) were used as controls. The combined analysis of the qualitative and quantitative variables was carried out with Gower distance and an unified data matrix with 315 descriptors. The relationships between the genetic distances differentiated the bean collection into two genetic groups: Andean and Mesoamerican. The following groups of characteristics presented high association: total morphology with qualitative morphology (P=0.91), physiological evaluation with grouped evaluation of morphological, quantitative, and physiological characteristics (P=0.91), characterization of isoenzymatic and molecular markers with respect to just molecular markers (P=0.99) and the characterization of all the studied markers in relation to the molecular and isoenzymatic markers (P=0.88)

Etnobotánica médica urbana y periurbana de la ciudad de Córdoba (Argentina)

Se presenta un estudio etnobotánico de los conocimientos y prácticas referidos al uso, rol y significado de los vegetales usados por practicantes de la medicina no oficial en poblaciones urbanas y periurbanas de la ciudad de Córdoba, Argentina. En este ámbito de estudio, se conforma un complejo cultural de saberes y prácticas locales y foráneas, típicas de culturas modernas. Se destaca el protagonismo de diversos actores sociales los que actúan como conectores culturales entre escenarios urbanos y rurales, los que combinan elementos tradicionales con los de la biomedicina, como así también los que forman parte de una larga cadena de comercialización de hierbas medicinales. Se recurrió a métodos cualitativos y cuantitativos mediante técnicas clásicas etnobotánicas. Se documentaron un total de 768 usos terapéuticos correspondientes a 262 taxones medicinales de estatus autóctonos y exóticos que pertenecen a 95 familias de plantas comercializadas en el ámbito urbano y periurbano. Se advierte una farmacopea urbana altamente diversificada en especies y aplicaciones con un predominio de especies exóticas (60%) como así también la presencia influyente de las medicinas alternativas complementarias y de medicinas globales en estos contextos

Niflumic acid disrupts marine spermatozoan chemotaxis without impairing the spatiotemporal detection of chemoattractant gradients

In many broadcast-spawning marine organisms, oocytes release chemicals that guide conspecific spermatozoa towards them through chemotaxis. In the sea urchin Lytechinus pictus, the chemoattractant peptide speract triggers a train of fluctuations of intracellular Ca(2+) concentration in the sperm flagella. Each transient Ca(2+) elevation leads to a momentary increase in flagellar bending asymmetry, known as a chemotactic turn. Furthermore, chemotaxis requires a precise spatiotemporal coordination between the Ca(2+)-dependent turns and the form of chemoattractant gradient. Spermatozoa that perform Ca(2+)-dependent turns while swimming down the chemoattractant gradient, and conversely suppress turning events while swimming up the gradient, successfully approach the center of the gradient. Previous experiments in Strongylocentrotus purpuratus sea urchin spermatozoa showed that niflumic acid (NFA), an inhibitor of several ion channels, drastically altered the speract-induced Ca(2+) fluctuations and swimming patterns. In this study, mathematical modeling of the speract-dependent Ca(2+) signaling pathway suggests that NFA, by potentially affecting hyperpolarization-activated and cyclic nucleotide-gated channels, Ca(2+)-regulated Cl(-) channels and/or Ca(2+)-regulated K(+) channels, may alter the temporal organization of Ca(2+) fluctuations, and therefore disrupt chemotaxis. We used a novel automated method for analyzing sperm behavior and we identified that NFA does indeed disrupt chemotactic responses of L. pictus spermatozoa, although the temporal coordination between the Ca(2+)-dependent turns and the form of chemoattractant gradient is unaltered. Instead, NFA disrupts sperm chemotaxis by altering the arc length traveled during each chemotactic turning event. This alteration in the chemotactic turn trajectory disorientates spermatozoa at the termination of the turning event. We conclude that NFA disrupts chemotaxis without affecting how the spermatozoa decode environmental cues.Consejo Nacional de Ciencia Tecnología grants: (49113, 128566, 132478), Programa de Apoyo a Proyectos de Investigación e Innovación Technológica grants: (IN211809, DGAPA/IXTLIIX200910, IN223810, IN109210-F)

Restoring catalase activity in Staphylococcus aureus subsp. anaerobius leads to loss of pathogenicity for lambs

Staphylococcus aureus subsp. anaerobius, a microaerophilic and catalase-negative bacterium, is the etiological agent of abscess disease, a specific chronic condition of sheep and goats, which is characterized by formation of necrotic lesions that are located typically in superficial lymph nodes. We constructed an isogenic mutant of S. aureus subsp. anaerobius (RDKA84) that carried a repaired and functional catalase gene from S. aureus ATCC 12600, to investigate whether the lack of catalase in S. aureus subsp. anaerobius plays a role in its physiological and pathogenic characteristics. The catalase activity had no apparent influence on the in vitro growth characteristics of RDKA84, which, like the wild-type, did not grow on aerobically incubated agar plates. Restoration of catalase activity in RDKA84 substantially increased resistance to H2O2 when analyzed in a death assay. The intracellular survival rates of the catalase-positive mutant RDKA84 in polymorphonuclear neutrophils (PMN) isolated from adult sheep were significantly higher than those of the wild-type, while no differences were found with PMN isolated from lambs. RDKA84 showed significantly lower survival rates in murine macrophages (J774A.1 cells) than the wild-type strains did, whereas, in bovine mammary epithelial cells (MAC-T), no differences in intracellular survival were observed. Interestingly, the virulence for lambs, the natural host for abscess disease, of the catalase-positive mutant RDKA84 was reduced dramatically in comparison with wild-type S. aureus subsp. anaerobius in two experimental models of infection

The Role of Intra-Clutch Variation of Magpie Clutches in Foreign Egg Rejection Depends on the Egg Trait Considered.

MM-M and JA conceived the idea and analyzed the data. MM-M led the writing of the manuscript. MP and JGM performed the experiment in the field work. JG and GL-C carried out the images processing and performed the analyzes related to fractal dimension. All authors contributed critically to the drafts and gave final approval for publication.We thank Brian Peer for inviting us to contribute to this special issue. We are also indebted to Daniel Hanley and Vanina Dafne Fiorini for comments that greatly improved the manuscript.The existence of a coevolutionary process between avian brood parasites and their hosts predicts a lower intra-clutch variation in egg appearance of host eggs among rejecters as this would favor egg discrimination of parasite eggs by hosts once parasitic egg mimicry had evolved. So far empirical tests of this prediction have ignored the fact that different aspects of host egg phenotypes may differ in the relative role of environmental vs. genetic determination, and hence that the role of intra-clutch variation in egg rejection within a population cannot be invariant. Here, we estimated whether the intra-clutch variation in several aspects of host eggshell features is consistently associated to rejection of parasitic foreign eggs across years in a magpie host population parasitized by great spotted cuckoos. We innovatively estimated spottiness by means of the fractal dimension of eggs, which considers the homogeneity of spot pattern complexity in eggshells. Our results show that low intra-clutch variation in the blue-green coloration at the middle area of the eggs associated with a high chance of rejection, but only in one of the 3 years we conducted the study. In addition, females that rejected foreign eggs presented more homogenous spot patterns in their clutches as estimated by their fractal dimension than females that accepted experimental eggs, independently of the year of study. Finally, intra-clutch variation in egg volume of host eggs was not associated to rejection. Analyses at the individual level revealed that the relative role of genetic vs. environmental factors that determine egg phenotype would be feature-specific in magpies, females having a characteristic spottiness, but not color or volume, pattern. Our work stresses the importance of considering a holistic approach including several aspects of variation in host egg phenotype (size, color, and homogeneity of spot pattern), as some aspects might be more susceptible to selection through egg rejection than others, presumably because they are less influenced by variation in the environmental conditions. Moreover, our study highlights the importance of replication in studies on the adaptive value of host traits in egg rejection.This study was made possible through funding by the Spanish Ministry of Science through different projects (CGL2011-27561 and CGL2014-55362-P), a grant (BES-2015-075675), the Juan de la Cierva–Incorporación Fellowship (IJC2018-036411-I), and the Junta de Andalucía through a project (P06-RNM-01862)

Transport Properties of the Diluted Lorentz Slab

We study the behavior of a point particle incident from the left on a slab of a randomly diluted triangular array of circular scatterers. Various scattering properties, such as the reflection and transmission probabilities and the scattering time are studied as a function of thickness and dilution. We show that a diffusion model satisfactorily describes the mentioned scattering properties. We also show how some of these quantities can be evaluated exactly and their agreement with numerical experiments. Our results exhibit the dependence of these scattering data on the mean free path. This dependence again shows excellent agreement with the predictions of a Brownian motion model.Comment: 14 pages of text in LaTeX, 7 figures in Postscrip