La producción caprina en La Pampa, ganadería agroecológica, propuestas y necesidades de investigación

Se analizan en este trabajo algunos aspectos de los sistemas de producción caprina del oeste pampeano, puntualizando experiencias tendientes a la sustentabilidad de los mismos dentro del marco de una ganadería agroecológica. Las experiencias relatadas se han desarrollado en el marco de diferentes Programas y Proyectos en los que han participado el INTA, el Ministerio de la Producción de La Pampa, la Secretaría de Agricultura Familiar, la Universidad de La Pampa y crianceros independientes, nucleados en la Asociación de Criadores de la Cabra Colorada Pampeana .Asimismo, se proponen algunas líneas de investigación, especialmente referidas a la recuperación de saberes populares, a la utilización de zooterápicos naturales y de plantas forrajeras nativas y exóticas, como también referidas al manejo del sistema de pastoreo sobre el monte natural, con el fin de disminuir la incidencia de la introducción de insumos como medicamentos y alimentos externos al sistema.Eje B1 Sistemas de producción de base agroecológica (Relatos de experiencias)Facultad de Ciencias Agrarias y Forestale

La producción caprina en La Pampa, ganadería agroecológica, propuestas y necesidades de investigación

Se analizan en este trabajo algunos aspectos de los sistemas de producción caprina del oeste pampeano, puntualizando experiencias tendientes a la sustentabilidad de los mismos dentro del marco de una ganadería agroecológica. Las experiencias relatadas se han desarrollado en el marco de diferentes Programas y Proyectos en los que han participado el INTA, el Ministerio de la Producción de La Pampa, la Secretaría de Agricultura Familiar, la Universidad de La Pampa y crianceros independientes, nucleados en la Asociación de Criadores de la Cabra Colorada Pampeana .Asimismo, se proponen algunas líneas de investigación, especialmente referidas a la recuperación de saberes populares, a la utilización de zooterápicos naturales y de plantas forrajeras nativas y exóticas, como también referidas al manejo del sistema de pastoreo sobre el monte natural, con el fin de disminuir la incidencia de la introducción de insumos como medicamentos y alimentos externos al sistema.Eje B1 Sistemas de producción de base agroecológica (Relatos de experiencias)Facultad de Ciencias Agrarias y Forestale

The envelopes of amphibian oocytes: physiological modifications in Bufo arenarum

A characterization of the Amphibian Bufo arenarum oocyte envelope is presented. It was made in different functional conditions of the oocyte: 1) when it has been released into the coelomic cavity during ovulation (surrounded by the coelomic envelope, (CE), 2) after it has passed through the oviduct and is deposed (surrounded by the viteline envelope, (VE), and 3) after oocyte activation (surrounded by the fertilization envelope, (FE). The characterization was made by SDS-PAGE followed by staining for protein and glycoproteins. Labeled lectins were used to identify glycosidic residues both in separated components on nitrocellulose membranes or in intact oocytes and embryos. Proteolytic properties of the content of the cortical granules were also analyzed. After SDS-PAGE of CE and VE, a different protein pattern was observed. This is probably due to the activity of a protease present in the pars recta of the oviduct. Comparison of the SDS-PAGE pattern of VE and FE showed a different mobility for one of the glycoproteins, gp75. VE and FE proved to have different sugar residues in their oligosaccharide chains. Mannose residues are only present in gp120 of the three envelopes. N-acetyl-galactosamine residues are present in all of the components, except for gp69 in the FE. Galactose residues are present mainly in gp120 of FE. Lectin-binding assays indicate the presence of glucosamine, galactose and N-acetyl galactosamine residues and the absence (or non-availability) of N-acetyl-glucosamine or fucose residues on the envelopes surface. The cortical granule product (CGP) shows proteolytic activity on gp75 of the VE

Modelización mecánica del enfriamiento rápido en sistemas tipo gres porcelánico

This paper analyses the effect of cooling on mechanical behaviour, in particular, on the residual stresses that appear when materials of the porcelain tile type are involved. However, these compositions have a very complex microstructure, in which there are several crystalline phases and the glassy phase is not homogeneous. In this study a simpler composition was therefore formulated, using sodium feldspar as starting material to which quartz with different particle sizes was added. A viscoelastic model was used to estimate the residual stresses that develop during cooling. The parameters of the model were obtained either from the literature or were determined in laboratory tests. An assembly was designed that allowed non-contact measurement of the temperature at the top and bottom surfaces of the test pieces during cooling. The test pieces were subjected to different types of cooling and their residual stresses were then determined by the strain relaxation slotting metho

Variation and process of life history evolution in insular dwarfism as revealed by a natural experiment

Islands are a classic focus for evolutionary studies. One topic of great interest has been the evolution of “dwarfs,” significantly smaller island mammals relative to their continental counterparts. Although a consensus has been achieved regarding the multivariate ecological causes behind changes in body size, the processes involved remain largely unexplored. Life history variables, including age at first reproduction, growth rate, and longevity, are likely to be key to understanding the process of insular dwarfism. The Japanese archipelago, with its numerous islands, offers a unique natural experiment for the evolution of different sizes within the same group of organisms; namely, deer. Thus, we investigated eight deer populations with a total number of 52 individuals exhibiting body size variation, both extant and fossil, to clarify the effect of insularity on life history traits. We applied several methods to both extant and extinct populations to resolve life history changes among these deer populations. Skeletochronology, using lines of arrested growth formed in long bones (femur and tibia), successfully reconstructed body growth curves and revealed a gradual change in growth trajectories reflecting the degree of insularity. Slower growth rates with prolonged growth periods in more isolated deer populations were revealed. An extensive examination of bone microstructure further corroborated this finding, with much slower growth and later somatic maturity evident in fossil insular deer isolated for more than 1.5 Myr. Finally, mortality patterns assessed by demographic analysis revealed variation among deer populations, with a life history of insular populations shifting toward the “slow life.”Hayashi S., Kubo M.O., Sánchez-Villagra M.R., et al. Variation and process of life history evolution in insular dwarfism as revealed by a natural experiment. Frontiers in Earth Science 11, 1095903 (2023); https://doi.org/10.3389/feart.2023.1095903

Large-area van der Waals epitaxy and magnetic characterization of Fe3GeTe2films on graphene

Scalable fabrication of magnetic 2D materials and heterostructures constitutes a crucial step for scaling down current spintronic devices and the development of novel spintronic applications. Here, we report on van der Waals (vdW) epitaxy of the layered magnetic metal Fe3GeTe2 (FGT) - a 2D crystal with highly tunable properties and a high prospect for room temperature ferromagnetism (FM) - directly on graphene by employing molecular beam epitaxy. Morphological and structural characterization confirmed the realization of large-area, continuous FGT/graphene heterostructure films with stable interfaces and good crystalline quality. Furthermore, magneto-transport and x-ray magnetic circular dichroism investigations confirmed a robust out-of-plane FM in the layers, comparable to state-of-the-art exfoliated flakes from bulk crystals. These results are highly relevant for further research on wafer-scale growth of vdW heterostructures combining FGT with other layered crystals such as transition metal dichalcogenides for the realization of multifunctional, atomically thin devices.They also acknowledge the provision of beamtime under the project HC-4068 at the European Synchrotron Radiation Facility (ESRF), located in Grenoble (France). ICN2 researchers acknowledge support from the European Union Horizon 2020 research and innovation programme under Grant Agreement No. 881603 (Graphene Flagship)

A phase II dose‑escalation trial of perioperative desmopressin (1‑desamino‑8‑D‑arginine vasopressin) in breast cancer patients

Desmopressin (dDAVP) is a well-known peptide analog of the antidiuretic hormone vasopressin, used to prevent excessive bleeding during surgical procedures. dDAVP increases hemostatic mediators, such as the von Willebrand factor (vWF), recently considered a key element in resistance to metastasis. Studies in mouse models and veterinary trials in dogs with locally-advanced mammary tumors demonstrated that high doses of perioperative dDAVP inhibited lymph node and early blood-borne metastasis and significantly prolonged survival. We conducted a phase II dose-escalation trial in patients with breast cancer, administering a lyophilized formulation of dDAVP by intravenous infusion in saline, 30–60 min before and 24 h after surgical resection. Primary endpoints were safety and tolerability, as well as selection of the best dose for cancer surgery. Secondary endpoints included surgical bleeding, plasma levels of vWF, and circulating tumor cells (CTCs) as measured by quantitative PCR of cytokeratin-19 transcripts. Only 2 of a total of 20 patients experienced reversible adverse events, including hyponatremia (grade 4) and hypersensitivity reaction (grade 2). Reactions were adequately managed by slowing the infusion rate. A reduced intraoperative bleeding was noted with increasing doses of dDAVP. Treatment was associated with higher vWF plasma levels and a postoperative drop in CTC counts. At the highest dose level evaluated (2 μg/kg) dDAVP appeared safe when administered in two slow infusions of 1 μg/kg, before and after surgery. Clinical trials to establish the effectiveness of adjunctive perioperative dDAVP therapy are warranted. This trial is registered on www.clinicaltrials.gov (NCT01606072).Facultad de Ciencias Médica

A phase II dose-escalation trial of perioperative desmopressin (1-desamino-8-d-arginine vasopressin) in breast cancer patients

Desmopressin (dDAVP) is a well-known peptide analog of the antidiuretic hormone vasopressin, used to prevent excessive bleeding during surgical procedures. dDAVP increases hemostatic mediators, such as the von Willebrand factor (vWF), recently considered a key element in resistance to metastasis. Studies in mouse models and veterinary trials in dogs with locally-advanced mammary tumors demonstrated that high doses of perioperative dDAVP inhibited lymph node and early blood-borne metastasis and significantly prolonged survival. We conducted a phase II dose-escalation trial in patients with breast cancer, administering a lyophilized formulation of dDAVP by intravenous infusion in saline, 30–60 min before and 24 h after surgical resection. Primary endpoints were safety and tolerability, as well as selection of the best dose for cancer surgery. Secondary endpoints included surgical bleeding, plasma levels of vWF, and circulating tumor cells (CTCs) as measured by quantitative PCR of cytokeratin-19 transcripts. Only 2 of a total of 20 patients experienced reversible adverse events, including hyponatremia (grade 4) and hypersensitivity reaction (grade 2). Reactions were adequately managed by slowing the infusion rate. A reduced intraoperative bleeding was noted with increasing doses of dDAVP. Treatment was associated with higher vWF plasma levels and a postoperative drop in CTC counts. At the highest dose level evaluated (2 μg/kg) dDAVP appeared safe when administered in two slow infusions of 1 μg/kg, before and after surgery. Clinical trials to establish the effectiveness of adjunctive perioperative dDAVP therapy are warranted. This trial is registered on www.clinicaltrials.gov (NCT01606072).Fil: Weinberg, Ruth S.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Grecco, Marcelo O.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Ferro, Gimena S.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Seigelshifer, Debora Judith. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Perroni, Nancy V.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Terrier, Francisco J.. Instituto Universitario del Hospital Italiano de Buenos Aires; ArgentinaFil: Sánchez Luceros, Analía Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; Argentina. Academia Nacional de Medicina de Buenos Aires; ArgentinaFil: Maronna, Esteban. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; ArgentinaFil: Sánchez Marull, Ricardo. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; ArgentinaFil: Frahm, Isabel. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; ArgentinaFil: Guthmann, Marcelo D.. Laboratorio Elea; ArgentinaFil: Di Leo, Daniela. Laboratorio Elea; ArgentinaFil: Spitzer, Eduardo. Laboratorio Elea; ArgentinaFil: Ciccia, Graciela Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garona, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Pifano, Marina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Torbidoni, Ana Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Gomez, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Ripoll, Giselle Vanina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Gomez, Roberto E.. Laboratorio Elea; ArgentinaFil: Demarco, Ignacio A.. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alonso, Daniel Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; Argentin

A Pliocene-Pleistocene continental biota from Venezuela

The Pliocene-Pleistocene transition in the Neotropics is poorly understood despite the major climatic changes that occurred at the onset of the Quaternary. The San Gregorio Formation, the younger unit of the Urumaco Sequence, preserves a fauna that documents this critical transition. We report stingrays, freshwater bony fishes, amphibians, crocodiles, lizards, snakes, aquatic and terrestrial turtles, and mammals. A total of 49 taxa are reported from the Vergel Member (late Pliocene) and nine taxa from the Cocuiza Member (Early Pleistocene), with 28 and 18 taxa reported for the first time in the Urumaco sequence and Venezuela, respectively. Our findings include the first fossil record of the freshwater fishes Megaleporinus, Schizodon, Amblydoras, Scorpiodoras, and the pipesnake Anilius scytale, all from Pliocene strata. The late Pliocene and Early Pleistocene ages proposed here for the Vergel and Cocuiza members, respectively, are supported by their stratigraphic position, palynology, nannoplankton, and 86 Sr/ 88 Sr dating. Mammals from the Vergel Member are associated with the first major pulse of the Great American Biotic Interchange. In contrast to the dry conditions prevailing today, the San Gregorio Formation documents mixed open grassland/forest areas surrounding permanent freshwater systems, following the isolation of the northern South American basin from western Amazonia. These findings support the hypothesis that range contraction of many taxa to their current distribution in northern South America occurred rapidly during at least the last 1.5 million years

Variation and process of life history evolution in insular dwarfism as revealed by a natural experiment

Islands are a classic focus for evolutionary studies. One topic of great interest has been the evolution of “dwarfs,” significantly smaller island mammals relative to their continental counterparts. Although a consensus has been achieved regarding the multivariate ecological causes behind changes in body size, the processes involved remain largely unexplored. Life history variables, including age at first reproduction, growth rate, and longevity, are likely to be key to understanding the process of insular dwarfism. The Japanese archipelago, with its numerous islands, offers a unique natural experiment for the evolution of different sizes within the same group of organisms; namely, deer. Thus, we investigated eight deer populations with a total number of 52 individuals exhibiting body size variation, both extant and fossil, to clarify the effect of insularity on life history traits. We applied several methods to both extant and extinct populations to resolve life history changes among these deer populations. Skeletochronology, using lines of arrested growth formed in long bones (femur and tibia), successfully reconstructed body growth curves and revealed a gradual change in growth trajectories reflecting the degree of insularity. Slower growth rates with prolonged growth periods in more isolated deer populations were revealed. An extensive examination of bone microstructure further corroborated this finding, with much slower growth and later somatic maturity evident in fossil insular deer isolated for more than 1.5 Myr. Finally, mortality patterns assessed by demographic analysis revealed variation among deer populations, with a life history of insular populations shifting toward the “slow life.