Sindicador de canales de noticias

Chile violates Human Rights (and everyone can see it on Twitter)

CONICET Digital -

Chile violates Human Rights (and everyone can see it on Twitter) Bonnin, Juan Eduardo El texto hace un breve análisis del activismo digital en Twitter acerca de las violaciones a los derechos humanos en Chile, comparándolo con el informe Nunca Más en Argentina y, de esa manera, haciendo algunas preguntas acerca de qué tipo de memorias discursivas políticas podrán construirse en base a las redes sociales.El texto es mi columna mensual correspondiente al mes de noviembre.

Pleiotropic effects of alpha-SNAP M105I mutation on oocyte biology: ultrastructural and cellular changes that adversely affect female fertility in mice

CONICET Digital -

Pleiotropic effects of alpha-SNAP M105I mutation on oocyte biology: ultrastructural and cellular changes that adversely affect female fertility in mice de Paola, Maria Matilde; Miró, María Paz; Ratto, Marcelo Hector; Bátiz, Luis Federico; Michaut, Marcela Alejandra After sperm-oocyte fusion, cortical granules (CGs) located in oocyte cortex undergo exocytosis and their content is released into the perivitelline space to avoid polyspermy. Thus, cortical granule exocytosis (CGE) is a key process for fertilization success. We have demonstrated that alpha-SNAP -and its functional partner NSF- mediate fusion of CGs with the plasma membrane in mouse oocytes. Here, we examined at cellular and ultrastructural level oocytes from hyh (hydrocephalus with hop gait) mice, which present a missense mutation in the Napa gene that results in the substitution of methionine for isoleucine at position 105 (M105I) of alpha-SNAP. Mutated alpha-SNAP was mislocalized in hyh oocytes while NSF expression increased during oocyte maturation. Staining of CGs showed that 9.8% of hyh oocytes had abnormal localization of CGs and oval shape. Functional tests showed that CGE was impaired in hyh oocytes. Interestingly, in vitro fertilization assays showed a decreased fertilization rate for hyh oocytes. Furthermore, fertilized hyh oocytes presented an increased polyspermy rate compared to wild type ones. At ultrastructural level, hyh oocytes showed small mitochondria and a striking accumulation and secretion of degradative structures. Our findings demonstrate the negative effects of alpha-SNAP M105 mutation on oocyte biology and further confirm the relevance of alpha-SNAP in female fertility.

Simulating cosmological substructure in the solar neighbourhood

CONICET Digital -

Simulating cosmological substructure in the solar neighbourhood Simpson, Christine M.; Gargiulo, Ignacio Daniel; Gómez, Facundo Ariel; Grand, Robert J. J.; Maffione, Nicolas Pablo; Cooper, Andrew P.; Deason, Alis J.; Frenk, Carlos; Helly, John; Marinacci, Federico; Pakmor, Rüdiger We explore the predictive power of cosmological, hydrodynamical simulations for stellar phase-space substructure and velocity correlations with the AURIGA simulations and AURIGAIA mock Gaia catalogues. We show that at the solar circle the AURIGA simulations commonly host phase-space structures in the stellar component that have constant orbital energies and arise from accreted subhaloes. These structures can persist for a few Gyr, even after coherent streams in position space have been erased. We also explore velocity two-point correlation functions and find this diagnostic is not deterministic for particular clustering patterns in phase space. Finally, we explore these structure diagnostics with the AURIGAIA catalogues and show that current catalogues have the ability to recover some structures in phase space but careful consideration is required to separate physical structures from numerical structures arising from catalogue generation methods.

La metamorfosis de una economía agraria en la pampa argentina: Buenos Aires y Santa Fe entre las décadas de 1850 y 1890

CONICET Digital -

La metamorfosis de una economía agraria en la pampa argentina: Buenos Aires y Santa Fe entre las décadas de 1850 y 1890; The Transformation of an Agrarian Economy in Argentine Pampa: Buenos Aires and Santa Fe between the 1850s and 1890s Barcos, Maria Fernanda; Martiren, Juan Luis El trabajo analiza la evolución de las economías agrarias de dos provincias del área pampeana entre las décadas de 1850 y 1890, un período clave para la transformación agrícola argentina. El objetivo central es proponer una mirada comparativa entre Buenos Aires y Santa Fe, que permita examinar las distintas etapas y las características diferenciales que tuvo el desarrollo de la agricultura pampeana hasta transformarse en una de las principales actividades económicas en el cambio de siglo. Los casos presentados buscan evidenciar cómo los ensayos de colonización agrícola santafesina lograron asentar una receta productiva de agricultura extensiva que desplazaría no solo a las tradicionales formas de producción agraria bonaerense, sino que también competiría con su dinámica producción ganadera.; The paper focuses on the divergent evolution of two agrarian economies in Argentine pampas between the decades of 1850 and 1890 . Through a comparative exercise of Buenos Aires and Santa Fe provinces, the paper tries to show the stages and the particular charac-teristics that addressed the development of Pampean agriculture expansion till the turn of the century . We assume that farming agriculture in Santa Fe succeeded to expand a produc-tive recipe of extensive agriculture that would displace not only the traditional forms of agri-cultural production in Buenos Aires, but also compete with its dynamic livestock production

Exsolution and electrochemistry in perovskite solid oxide fuel cell anodes: Role of stoichiometry in Sr(Ti,Fe,Ni)O3

CONICET Digital -

Exsolution and electrochemistry in perovskite solid oxide fuel cell anodes: Role of stoichiometry in Sr(Ti,Fe,Ni)O3 Zhu, Tenglong; Troiani, Horacio Esteban; Mogni, Liliana Verónica; Santaya, Mariano; Han, Minfang; Barnett, Scott A. The exsolution of metal cations from oxides under reducing fuel conditions results in the formation of surface metallic nanoparticles, which can reduce Solid Oxide Fuel Cell anode polarization resistance. However, the loss of the B-site cations shifts the stoichiometry of the perovskite oxide. Depending on the amount exsolved and the initial stoichiometry, the exsolution can presumably shift the oxide away from its single-phase perovskite region. Herein, the direct comparison of initially stoichiometric composition Sr(Ti0.3Fe0.63Ni0.07)O3-δ (STFN0) with initially A-site deficient Sr0.95(Ti0.3Fe0.63Ni0.07)O3-δ (STFN5) is conducted and reported. X-ray diffraction along with scanning and transmission electron microscopy analysis of the oxides, which are both reduced at 850 °C in H2/H2O/Ar, shows a similar size and density of exsolved Fe–Ni alloy nanoparticles, albeit with slightly different alloy compositions. Whereas the oxide phase in reduced STFN5 shows a well-ordered perovskite structure, the greater B-site deficiency in reduced STFN0 results in a highly disordered and strained structure. The electrochemical performance of STFN0 anodes is inferior to that of STFN5 anodes, and even worse than SrTi0.3Fe0.7O3-δ (Ni-free) anodes. It appears that an initial Sr deficiency is important to avoid a too-high B-site deficiency after exsolution, which distorts the perovskite structure and impairs electrochemical processes.

Lógica del capital, crítica del valor y metapsicología freudiana: una reescritura categorial del pensamiento de León Rozitchner

CONICET Digital -

Lógica del capital, crítica del valor y metapsicología freudiana: una reescritura categorial del pensamiento de León Rozitchner; Logic of Capital, Critic of Value and Freudian Metapsychology: A Reading of the Thought of León Rozitchner Exposto, Emiliano; Rodriguez Varela, Gabriel El artículo realiza una interpretación de la lectura que el filósofo argentino León Rozitchner opera sobre la meta-psicología freudiana en sus textos Freud y los límites del individualismo burgués (1972) y Freud y el problema del poder (1985). El objetivo es explorar nuevas cifras de inteligibilidad para repensar el diálogo crítico entre psicoanálisis freudiano y marxismo, revisitando la concepción rozitchneriana sobre la subjetividad a partir de las categorías propiciadas por la teoría crítica del valor.; The article makes an interpretation of the reading that the argentine philosopher Leon Rozitchner operates on the Freudian meta-psychology in his texts Freud and the limits of bourgeois individualism (1972) and Freud and the problem of power (1985). The aim is to explore new intelligibility figures to rethink the critical dialogue between Freudian psychoanalysis and Marxism, revisiting Rozitchner's conception of subjectivity from the categories fostered by the critical theory of the value.

Ex vivo and in vivo effects of arsenite on GST and ABCC2 activity and expression in the middle intestine of the rainbow trout Oncorhynchus mykiss

CONICET Digital -

Ex vivo and in vivo effects of arsenite on GST and ABCC2 activity and expression in the middle intestine of the rainbow trout Oncorhynchus mykiss Painefilú, Julio César; Pascual, Mariano Martin; Bieczynski, Flavia; Laspoumaderes, Cecilia; González, Carolina; Villanueva, Silvina Stella Maris; Luquet, Carlos Marcelo In fish of freshwaters environments, the accumulation and toxic effects of arsenite (AsIII) can be attenuated by detoxification proteins such as GST and ABCC transporters. We studied the effects of AsIII on the middle intestine of O. mykiss in ex-vivo and in vivo/ex vivo assays. For the ex vivo assays, we measured the transport rate of the ABCC substrate DNP-SG and GST activity in intestinal strips and everted sacs. AsIII inhibited DNP-SG transport in a concentration-dependent manner, specifically when we applied it on the basolateral side. GST activity increased when we applied a maximum concentration of AsIII. For the in vivo/ex vivo assays, we kept fish in water with or without 7.7 μmol L− 1 of AsIII for 48 h. Then, we measured DNP-SG transport rate, GST activity, and PP1 activity in intestine strips during one hour. For PP1 activity, we incubated the strips with or without microcystin-LR (MCLR), a toxin excreted through ABCC2 proteins. We also analyzed Abcc2 and Gst-π mRNA expression in intestine and liver tissue. In the group exposed in vivo to AsIII, DNP-SG transport rate and GST activity were higher and the effect of MCLR over PP1 activity was attenuated. AsIII significantly induced only Abcc2 mRNA expression in both middle intestine and liver. Our results suggest that, in the middle intestine of O. mykiss, AsIII is absorbed mainly at the basolateral side of the enterocytes, excreted to the lumen by ABCC2 transporters, and is capable of modulating Abcc2 mRNA expression by a transcriptional mechanism.

Onset of foreland basin deposition in the Neuquén Basin (34°-35°S): New data from sedimentary petrology and U–Pb dating of detrital zircons from the Upper Cretaceous non-marine deposits

CONICET Digital -

Onset of foreland basin deposition in the Neuquén Basin (34°-35°S): New data from sedimentary petrology and U–Pb dating of detrital zircons from the Upper Cretaceous non-marine deposits Gómez, Ricardo Ernesto; Lothari, Lucas Daniel; Tunik, Maisa Andrea; Casadio, Silvio Alberto A multi-proxy provenance approach using sedimentology, petrology and detrital zircon U–Pb geochronology provides new constrains for the evolution of the Southern Central Andes. The Upper Cretaceous non-marine deposits of the Neuquén Basin referred as Neuquén Group in the central and southern sector of the basin, have been characterized as the first foreland basin associated with the early uplift of the Andean orogen at ca. 100 Ma. However, in the northern sector of the basin, the stratigraphically equivalent Diamante Formation has not been studied in detail yet. This work focuses in the outcrops of the Diamante Formation located between Laguna del Diamante and Atuel River in southern Mendoza Province, Argentina (34°-35°S). The petrographic analysis of sandstones shows high content of volcanic and calcareous lithic fragments suggesting provenance from the underlying sedimentary units and the coeval volcanic arc associated with the onset of an important stage of deformation on the west. Detrital zircons from the base of the Diamante Formation were supplied sources from Upper Jurassic and Lower Cretaceous that were exposed during Upper Cretaceous times, whereas in the top, a high content of Permo-Triassic detrital zircons indicates exhumation of the surrounding Permo-Triassic crystalline basement. Finally, two maximum depositional ages were obtained, 107.2 ± 1.4 Ma to Vega de los Patos and 91.1 ± 2.2 Ma to Vega Grande, suggesting uninterrupted activity of the volcanic arc during foreland basin deposition. In particular, the age of 107.2 Ma would indicate that the sedimentation of the Upper Cretaceous non-marine deposits occurred in the Albian at these latitudes (34°-35°S), which suggests that the onset of the foreland basin sedimentation is diachronic at different positions in the Neuquén Basin.

El Dinggedicht en la crisis de la representación: Un ejemplo del poeta Paul Zech

CONICET Digital -

El Dinggedicht en la crisis de la representación: Un ejemplo del poeta Paul Zech; The Dinggedicht in the Crisis of Representation: An Example by the Poet Paul Zech Sufotinsky Reynoso, Eric Tomás El Dinggedicht (poema-objeto) es un tipo de composición poética de cierta tradición en la lírica alemana que, en el marco de la crisis de la representación artística que comienza a mediados del siglo XIX y en el del período de las vanguardias históricas, adquiere una importancia particular como forma de elaboración del objeto artístico. Dentro de su tradición, han sido Rainer Maria Rilke –tanto por sus producciones como por sus reflexiones al respecto– y Paul Zech grandes exponentes de este tipo de forma poética.; The Dinggedicht (object-poem) is a kind of poetic composition. It has a certain tradition in German poetry. It develops in the context of art representation crisis –which begins in the mid-19th century– and of the historical avant-gardes. During this period, the Dinggedicht acquires a peculiar significance as a way of elaborating the artistic object. Within its tradition Rainer Maria Rilke –not only because of his productions, but also because of his reflections on the subject– and Paul Zech were among the most important exponents of this kind of poetic form.

Taphonomic field experiment in a freshwater shallow lake: alteration of gastropod shells below the sediment–water interface

CONICET Digital -

Taphonomic field experiment in a freshwater shallow lake: alteration of gastropod shells below the sediment–water interface Cristini, Paula Andrea; de Francesco, Claudio German We conducted a taphonomic field experiment to evaluate the effects of (1) depth below the sediment-water interface (SWI) and (2) time of exposure on the accrual of damage (particularly through dissolution) to empty mollusc shells in freshwater environments. The experiment, which lasted 30 months, was carried out in the littoral area of Lake Nahuel Rucá, a shallow freshwater lake in the Pampa plain of Argentina. Bags (0.5-cm mesh) containing empty, cleaned shells of the freshwater gastropods Heleobia parchappii, Biomphalaria peregrina and Pomacea canaliculata were buried at three different depths (5, 20 and 35 cm) below the SWI. Damage was assessed every 3 months. All experimental shells exhibited fine-scale surface alteration, but the extent of this damage was relatively low, even in shells recovered after 30 months of exposure. Most of the damage consisted of minor pitting. For H. parchappii and B. peregrina, shell surface alteration varied significantly with depth, but not with time; in both species, alteration occurred mainly at the beginning of the experiment. For P. canaliculata, shell surface alteration varied significantly only with respect to time and this was the case for all three burial depths. All shells of this species exhibited a lower level of damage than what was observed for H. parchappii and B. peregrina. These differences may be related to the fact that P. canaliculata is characterized by a larger and thicker shell than the other two species. The shell attributes of larger size and greater thickness are known to confer a greater resistance to shell dissolution. In addition, the reactive surface area available for dissolution varies with shell size. Larger-sized shells have a lower potential for dissolution than smaller shells due to their lower surface-Area-To-volume ratio. In contrast, species such as H. parchappii and B. peregrina, which have smaller and thinner shells, are likely to be more rapidly destroyed because they are more vulnerable to dissolution and have less preservation potential. Our results demonstrate that dissolution is a significant taphonomic process affecting shells even during burial and that the influence of dissolution on shell alteration might be significant in cases of long persistence within the taphonomically active zone. Consequently, we suggest that when working on taphofacies in the context of aquatic environments, assessments of taphonomic alteration should include changes at and below the SWI.

Embryo presence regulates NODAL/LEFTY2 system in the rat oviduct in vivo

CONICET Digital -

Embryo presence regulates NODAL/LEFTY2 system in the rat oviduct in vivo Argañaraz, Martin Eduardo; Zampini, Renato; Apichela, Silvana Andrea; Barraza, Daniela Estefanía; Angiono, Georgina Melisa; Lombardo, Daniel Marcelo To gain further insight in the mechanisms of the embryo–maternal dialog in the oviduct, expression of members of the transforming growth factor‐β superfamily, NODAL, its inhibitor, LEFTY2, and their coreceptor, CFC1, were studied in the oviduct of 3‐day post copula (3 dpc) females with and without embryos (E and NE), pseudopregnant rats (SP3), and in 3‐day embryos. Nodal transcripts in SP3 oviducts showed a steady‐state relative abundance when compared with proestrus stage and the 3 dpc. In contrast, Lefty2 and Cfc1 relative abundance levels in proestrus and 3 dpc were higher. When comparing E with NE oviducts, Nodal and Lefty2 expression levels decreased, while Cfc1 expression increased in the presence of embryos. Nodal messenger RNA (mRNA) was observed in the embryo, but Lefty2 and Cfc1 transcripts were not found. In addition, an increase in Lefty2 expression coincided with increased levels of matrix metalloproteinases 9 mRNA and protein in the oviduct and in the oviductal fluid, respectively. These observations have shed new light on the relevance of the NODAL/LEFTY2 pathway in the oviduct during early embryo development and the role of the embryo in modulating this pathway.

Obtaining an Ent35-MccV derivative with mutated hinge region that exhibits increased activity against listeria monocytogenes and escherichia coli

CONICET Digital -

Obtaining an Ent35-MccV derivative with mutated hinge region that exhibits increased activity against listeria monocytogenes and escherichia coli Navarro, Silvia Adriana; Lanza, Lucía; Ríos Colombo, Natalia Soledad; Fernandez de Ullivarri, Miguel; Acuña, Leonardo; Sosa Padilla Araujo, Bernardo; Picariello, Gianluca; Bellomio, Augusto; Chalon, Miriam Carolina The present paper describes the generation of derivatives from the hybrid peptide called Ent35-MccV, active against Gram-positive and Gram-negative bacteria. This peptide has a triple glycine hinge region between enterocin CRL35 and microcin V. In order to obtain variants of Ent35-MccV with greater biotechnological potential, a saturation mutagenesis was carried out in the hinge region. As a result, we obtained a bank of E.coli strains expressing different mutated hybrid bacteriocins in the central position of the hinge region. From all these variants, we found that the one bearing a tyrosine in the central region of the hinge (Ent35-GYG-MccV) is 2-fold more active against E. coli and 4-fold more active against Listeria than the original peptide Ent35-MccV. This derivative was purified and characterized. The development and evaluation of alternative hinges for Ent35-MccV represents a step forward in the bioengineering of antimicrobial peptides. This approach fosters the rational design of peptides with enhanced antimicrobial activity.

Fermentation innovation through complex hybridization of wild and domesticated yeasts

CONICET Digital -

Fermentation innovation through complex hybridization of wild and domesticated yeasts Langdon, Quinn K.; Peris, David; Baker, Emily Clare; Opulente, Dana A.; Nguyen, Huu-Vang; Bond, Ursula; Gonçalves, Paula; Sampaio, José Paulo; Libkind Frati, Diego; Hittinger, Chris The most common fermented beverage, lager beer, is produced by interspecies hybrids of the brewing yeast Saccharomyces cerevisiae and its wild relative S. eubayanus. Lager-brewing yeasts are not the only example of hybrid vigour or heterosis in yeasts, but the full breadth of interspecies hybrids associated with human fermentations has received less attention. Here we present a comprehensive genomic analysis of 122 Saccharomyces hybrids and introgressed strains. These strains arose from hybridization events between two to four species. Hybrids with S. cerevisiae contributions originated from three lineages of domesticated S. cerevisiae, including the major wine-making lineage and two distinct brewing lineages. In contrast, the undomesticated parents of these interspecies hybrids were all from wild Holarctic or European lineages. Most hybrids have inherited a mitochondrial genome from a parent other than S. cerevisiae, which recent functional studies suggest could confer adaptation to colder temperatures. A subset of hybrids associated with crisp flavour profiles, including both lineages of lager-brewing yeasts, have inherited inactivated S. cerevisiae alleles of critical phenolic off-flavour genes and/or lost functional copies from the wild parent through multiple genetic mechanisms. These complex hybrids shed light on the convergent and divergent evolutionary trajectories of interspecies hybrids and their impact on innovation in lager brewing and other diverse fermentation industries.

Supporting Spartina: Interdisciplinary perspective shows Spartina as a distinct solid genus

CONICET Digital -

Supporting Spartina: Interdisciplinary perspective shows Spartina as a distinct solid genus Bortolus, Alejandro; Adam, Paul; Adams, Janine B.; Ainouche, Malika L.; Ayres, Debra; Bertness, Mark D.; Bouma, Tjeerd J.; Bruno, John F.; Caçador, Isabel; Carlton, James T.; Castillo, Jesus M.; Costa, Cesar S. B.; Davy, Anthony J.; Deegan, Linda; Duarte, Bernardo; Figueroa, Enrique; Gerwein, Joel; Gray, Alan J.; Grosholz, Edwin D.; Hacker, Sally D.; Hughes, A. Randall; Mateos Naranjo, Enrique; Mendelssohn, Irving A.; Morris, James T.; Muñoz-Rodríguez, Adolfo F.; Nieva, Francisco J. J.; Levin, Lisa A.; Li, Bo; Liu, Wenwen; Pennings, Steven C.; Schwindt, Evangelina In 2014, a DNA-based phylogenetic study confirming the paraphyly of the grass subtribe Sporobolinae proposed the creation of a large monophyletic genus Sporobolus, including (among others) species previously included in the genera Spartina, Calamovilfa, and Sporobolus. Spartina species have contributed substantially (and continue contributing) to our knowledge in multiple disciplines, including ecology, evolutionary biology, molecular biology, biogeography, experimental ecology, biological invasions, environmental management, restoration ecology, history, economics, and sociology. There is no rationale so compelling to subsume the name Spartina as a subgenus that could rival the striking, global iconic history and use of the name Spartina for over 200 yr. We do not agree with the subjective arguments underlying the proposal to change Spartina to Sporobolus. We understand the importance of both the objective phylogenetic insights and of the subjective formalized nomenclature and hope that by opening this debate we will encourage positive feedback that will strengthen taxonomic decisions with an interdisciplinary perspective. We consider that the strongly distinct, monophyletic clade Spartina should simply and efficiently be treated as the genus Spartina.

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

CONICET Digital -

Etnobotánica médica urbana y periurbana de la ciudad de Córdoba (Argentina); Urban and peri-urban medical ethnobotany in the city of Córdoba (Argentina) Luján, María Claudia; Martínez, Gustavo Javier 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.; Following is submitted an ethnobotanic study on knowledge and practices on usage, role and meaning of plants and relatives used by practitioners of non-official medicine in urban and peri-urban places of the city of Córdoba, Argentina. In this study area, it can be observed a cultural structure of knowledge as well as local and foreign practices, which are typical of modern cultures. Diverse social actors perform as cultural connectors between urban and rural scenarios, which match traditional components with those of biomedicine as well as those that belong to a large chain of medical herbs marketing. Quantitative and qualitative methods were resorted to, through classical ethnobotanic techniques. An amount of 768 therapeutical usages were registered which correspond to 262 native and foreign medical taxons. These taxons belong to 95 family plants marketed within urban and peri-urban areas. It is also remarkable an urban pharmacopeia highly diverse as regards species and usages with a top level of exotic species (60%) as well as complementary alternative and global medicines in theses contexts.

Computational study of the hydrogen peroxide scavenging mechanism of allyl methyl disulfide, an antioxidant compound from garlic

CONICET Digital -

Computational study of the hydrogen peroxide scavenging mechanism of allyl methyl disulfide, an antioxidant compound from garlic Vega Hissi, Esteban Gabriel; Andrada, Matias Fernando; Diaz, Mario Guillermo; Garro Martinez, Juan Ceferino Although many sulfur containing garlic compounds present antioxidant activity, little is known about molecular mechanisms through which these compounds react with reactive oxygen species. In this work, the reactivity and the hydrogen peroxide scavenger reaction mechanisms (including thermodynamics and kinetics aspects) of allyl methyl disulfide in aqueous phase are studied employing density functional theory computational methods. Three reactive sites susceptible for electrophilic attack are found over sulfur atoms and the double bond allyl moiety. For each detected site, one redox reaction is proposed and analyzed. All reactions are thermodynamically feasible, whereas attack over the methyl bound sulfur atom is kinetically favored.

Polyamines and legumes: Joint stories of stress, nitrogen fixation and environment

CONICET Digital -

Polyamines and legumes: Joint stories of stress, nitrogen fixation and environment Menendez, Ana Bernardina; Calzadilla, Pablo Ignacio; Sansberro, Pedro Alfonso; Espasandin, Fabiana Daniela; Gázquez, Ayelén; Bordenave, César Daniel; Maiale, Santiago Javier; Rodriguez, Andres Alberto; Maguire, Vanina Giselle; Campestre, Maria Paula; Gárriz, Andrés; Rossi, Franco Rubén; Romero, Fernando Matias; Solmi, Leandro; Salloum, Maria Soraya; Monteoliva, Mariela Inés; Debat, Humberto Julio; Ruiz, Oscar Adolfo Polyamines (PAs) are natural aliphatic amines involved in many physiological processes in almost all living organisms, including responses to abiotic stresses and microbial interactions. On other hand, the family Leguminosae constitutes an economically and ecologically key botanical group for humans, being also regarded as the most important protein source for livestock. This review presents the profuse evidence that relates changes in PAs levels during responses to biotic and abiotic stresses in model and cultivable species within Leguminosae and examines the unreviewed information regarding their potential roles in the functioning of symbiotic interactions with nitrogen-fixing bacteria and arbuscular mycorrhizae in this family. As linking plant physiological behavior with “big data” available in “omics” is an essential step to improve our understanding of legumes responses to global change, we also examined integrative MultiOmics approaches available to decrypt the interface legumes-PAs-abiotic and biotic stress interactions. These approaches are expected to accelerate the identification of stress tolerant phenotypes and the design of new biotechnological strategies to increase their yield and adaptation to marginal environments, making better use of available plant genetic resources.

Diversificación económica y proyectos de fomento en Chile, Tucumán y Tarija (siglo XVIII)

CONICET Digital -

Diversificación económica y proyectos de fomento en Chile, Tucumán y Tarija (siglo XVIII); Economic Diversification and Promotion Projects in Chile, Tucuman and Tarija (18th Century) Soler Lizarazo, Luisa Consuelo; Cruz, Enrique Normando; Koeltzsch, Grit Kirstin El presente trabajo analiza las diversificaciones económicas y las iniciativas de fomento desarrollado en tres áreas de América del Sur, como son el Reino de Chile, la Gobernación del Tucumán y el Distrito de Tarija. Por medio de estudios de caso, se identifican, describen y detallan las diversas actividades económicas: comercial, agrícola, minera y protoindustrial, promovidas por agentes económicos mercantiles a finales del periodo colonial, utilizando como base correspondencia comercial privada, inventarios de mercancías, testimonios, juicios civiles y penales. Los resultados muestran que, pese a la importancia puesta al desarrollo de iniciativas de fomento productivo por parte de ciertos sectores político-burocráticos, los alcances fueron relativos, entre otras cosas por las dinámicas de los mercados, el sistema de financiamiento y el cálculo racional del beneficio.; This paper analyzes the diversification and initiatives of economic and productive promotion in the 18th century developed by traders in three areas of South America, which are the Kingdom of Chile, the Governorate of Tucuman and the Tarija district. Through case studies, the researchers identify, describe and provide details of the diverse economic activities: commercial, agricultural, mining and protoindustrial, promoted by economic mercantile agents at the end of the colonial period, based on commercial correspondence private, inventories of goods, testimonies, civil and criminal trials. The results show that, despite the importance placed on the development of initiatives to promote production by certain politicalbureaucratic sectors, the scope was relative, among other things due to the dynamics of the markets, the financing system and rational calculation of the profit.

"Las condiciones de mi sexo": Mujeres científicas argentinas frente a la memoria masculinizada

CONICET Digital -

"Las condiciones de mi sexo": Mujeres científicas argentinas frente a la memoria masculinizada; “The conditions of/on my sex”: Argentina women scientists against masculinised memory Gomez, Carina Elizabeth Este trabajo tiene como fin presentar el panorama social que rodeó el ingreso de las mujeres al ámbito académico universitario argentino en tanto acontecimiento histórico mediado por las relaciones de género. Se describe el contexto social en las postrimerías del siglo XIX y principios del XX en Argentina a partir de la configuración normativa así como la descripción de sucesos que buscaron irrumpir con el encierro doméstico femenino. Se examina el acceso femenino a la educación universitaria y los estudios científicos en el contexto argentino de principio del siglo XX cuando se registran los primeros trabajos de investigación de mujeres en las publicaciones científicas. Entramado a este contexto se describe la vida de Prosperina Paraván, una estudiante figura clave femenina en los sucesos de la Reforma Universitaria. Estos acontecimientos históricos son recordados desde la óptica masculina, subvalorando y relegando al olvido la insumisión de aquellas mujeres en las universidades argentinas.; This work aims to present the social atmosphere surrounding women´s admission to Argentinian university academic sphere as a historical event mediated by gender relations. The social context in late 20th and early 21st centuries in Argentina is also described, as regards its normative frame as well as the events which broke into female domestic confinement and women´s difficulties to access education. Furthermore, women's access to university education and scientific studies is examined in the Argentinian historical context of early 20th century, when the first women's research papers are registered. Within this context Prosperina Paravarán´s life is described. She was a Santafecina student of the Dentistry programme at the National University of Córdoba who actively participated in the events during the University Reform, thus becoming a prominent female figure. Even after women's admission to universities, the University Reform was redrafted from a male perspective, underestimating those pioneer women´s unsubmitting attitude in Argentinian universities and consigning them to oblivion.

Análisis morfométrico multiescalar en la cuenca alta del arroyo Sauce Corto (Buenos Aires, Argentina)

CONICET Digital -

Análisis morfométrico multiescalar en la cuenca alta del arroyo Sauce Corto (Buenos Aires, Argentina); Morphometric multiple-scale analysis in the upper basin of the Sauce Corto stream (Buenos Aires, Argentina); Análise morfométrica multiescala na bacia alta do arroio Sauce Corto (Buenos Aires, Argentina) Moretto, Belén; Gentili, Jorge Osvaldo; Campo, Alicia María En la cuenca alta del arroyo Sauce Corto (vertiente norte del Sistema de Ventania, provincia de Buenos Aires, Argentina), frecuentemente ocurren eventos extremos de precipitación que generan crecidas y dan lugar a inundaciones que afectan el desarrollo socio-económico del partido de Coronel Suárez. A fin de inferir la respuesta hidrológica del área de interés, es necesario el análisis de paramentos e índices morfométricos que permitan estudiar el peligro de inundación de las cuencas. El objetivo del trabajo es identificar las variaciones de la respuesta hidrológica de cuencas de interés en función de los parámetros e índices morfométricos obtenidos de distintas fuentes de datos y escalas. Los resultados del análisis multiescalar evidencian el peso de los procesos de generalización cartográfica asociados a la escala de semidetalle. En términos del análisis de la respuesta hidrológica es posible inferir que el uso de la escala 1:50.000 puede llevar a la subestimación de la torrencialidad de las cuencas y en consecuencia, de su grado de peligrosidad.; In the high basin of the Sauce Corto stream (in the Northern watershed of Ventania System in the Province of Buenos Aires), there are frequent extreme precipitation events, which generate floods that affect the socioeconomic development of Coronel Suárez district. In order to infer the hydrological response of the area, it is necessary to analyze the parameters and morphometric indexes that allow for the study of potentially dangerous basins flood. Accordingly, the aim of this paper is to identify variations in the hydrological response of different basins, according to parameters and morphometric indexes obtained from various data and scale sources. The multiple-scale analysis results show the importance of cartographic generalization processes associated to semi detail scaling. In the analysis of the hydrological response it is possible to infer that the use of 1:50.000 scale will possibly underestimate the basins torrentiality and, consequently, its potential danger.; Na bacia alta do arroio Sauce Corto (vertente norte do Sistema de Ventania, província de Buenos Aires, Argentina), frequentemente ocorrem eventos extremos de precipitação que geram crescidas e dão lugar a inundações que afetam o desenvolvimento sócio econômico do partido de Coronel Suarez. Com o fim de inferir a resposta hidrológica da área de interesse é necessário a análise de parâmetros e índices morfométricos que permitam estudar o perigo de inundação das bacias. A partir do exposto, o objetivo do trabalho é identificar as variações da resposta hidrológica das bacias de interesse em função dos parâmetros e índices morfométricos obtidos de diferentes fontes de dados e escalas. Os resultados da análise multiescala evidenciam o peso dos processos de generalização cartográfica associados numa escala de mínimos detalhes. Em termos de análise da resposta hidrológica é possível inferir que o uso da escala 1:50.000 pode subestimar as chuvas torrenciais das bacias e, em consequência, o grau de perigo das mesmas.

Páginas

Suscribirse a Facultad de Ciencias Químicas de la Universidad Nacional de Córdoba agregador