De los Perissodactyla europeos a los Notoungulata argentinos

Not availableNo disponibl

Calibrated forceps model of spinal cord compression injury.

Compression injuries of the murine spinal cord are valuable animal models for the study of spinal cord injury (SCI) and spinal regenerative therapy. The calibrated forceps model of compression injury is a convenient, low cost, and very reproducible animal model for SCI. We used a pair of modified forceps in accordance with the method published by Plemel et al. (2008) to laterally compress the spinal cord to a distance of 0.35 mm. In this video, we will demonstrate a dorsal laminectomy to expose the spinal cord, followed by compression of the spinal cord with the modified forceps. In the video, we will also address issues related to the care of paraplegic laboratory animals. This injury model produces mice that exhibit impairment in sensation, as well as impaired hindlimb locomotor function. Furthermore, this method of injury produces consistent aberrations in the pathology of the SCI, as determined by immunohistochemical methods. After watching this video, viewers should be able to determine the necessary supplies and methods for producing SCI of various severities in the mouse for studies on SCI and/or treatments designed to mitigate impairment after injury

Quebrada Fiera (Mendoza), un importante centro paleobiogeográfico en el Oligoceno tardío de América del Sur

This contribution focuses on the main results and present researches on the Oligocene fauna from Quebrada Fiera (Mendoza, Argentina). This vertebrate assemblage is providing new data on the distribution and evolution of South American Deseadan (late Oligocene) mammals. Descriptions of notoungulate Notohippidae and Archaeohyracidae have been recently published. A new genus of notohippid was identified, while most archaeohyracid material was recognized as the same species present in Salla (Bolivia). Studies in progress on other native ungulates (Hegetotheriidae, Interatheriidae, Leontinidae, Homalodotheriidae, Toxodontidae, ?Proterotheriidae, and Pyrotheriidae), metatheria, xenarthra, and rodents from Quebrada Fiera will increase the knowledge of this fauna. Preliminarily, the faunal association appears as a mix of taxa. On the one hand, with Patagonian affinities, on the other hand, related to species known from lower latitudes (Bolivia), together with exclusive taxa such as Mendozahippus (Notohippidae). The ongoing research will allow a better understanding of the role of Mendoza area in the paleobiogeographic and biostratigraphic context of the South American Oligocene mammals.Esta contribución se centra en los principales resultados obtenidos en los últimos años sobre la fauna oligocena de Quebrada Fiera (Mendoza, Argentina) y las investigaciones en curso. La asociación faunística de Quebrada Fiera está aportando datos nuevos sobre la distribución y la evolución de los mamíferos sudamericanos de la Edad mamífero Deseadense. Recientemente, se han dado a conocer los restos de dos familias de notoungulados, Notohippidae y Archaeohyracidae. En el primer caso, se reconoció un género nuevo, mientras que los arqueohirácidos se identifican en su gran mayoría como la especie presente en Salla (Bolivia). Los estudios en curso sobre otras familias de ungulados nativos (Hegetotheriidae, Interatheriidae, Leontinidae, Homalodotheriidae, Toxodontidae, ?Proterotheriidae y Pyrotheriidae), así como de los restos de metaterios, xenartros y roedores recuperados en Quebrada Fiera, ampliarán el conocimiento detallado de esta fauna. De forma preliminar, el conjunto faunístico aparece como una mezcla de taxones; por un lado, con afinidades patagónicas y, por otro, relacionados con especies conocidas en latitudes bajas (Bolivia), al mismo tiempo que cuenta con representantes exclusivos como Mendozahippus (Notohippidae). El avance de las investigaciones permitirá comprender mejor el papel del área de Mendoza en las distribuciones paleobiogeográfica y bioestratigráfica de los mamíferos sudamericanos del Oligoceno tardío

EXPLORING THE EFFICACY OF FACEBOOK- BASED TRAINING IN ENHANCING EXECUTIVE FUNCTIONS FOR ACQUIRED BRAIN INJURY PATIENTS

openAcquired brain injury (ABI) is a prevalent disorder in the population, characterized by the presence of impairments in executive functions that can become greatly disabling, hence there is a need for highly effective treatments. The following intervention proposal aims to use tools and resources available on the Facebook platform to create a series of tasks that complement the process-based neuropsychological rehabilitation program for this type of patients. The general objective of this proposal is to design, implement and test the effectiveness of an intervention program based on cognitive training through the use of Facebook, in order to improve executive deficits present in patients with ABI. In addition, we will study the potential effects on memory functions and social skills. To achieve this, 24 patients will be recruited to participate in a 9-session treatment, and will be evenly divided into two groups, either the experimental or the control. Following the intervention, even though each group is expected to present enhancements in the assessed executive sub- processes (cognitive flexibility, attentional control, goal setting and information processing), we anticipate significant differences between them. In this way, the experimental group will show a significant improvement in executive functioning in addition to an increase in social skills and memory. This approach represents important and innovative implications for future research compared to other well-established procedures, as it offers numerous advantages, such as low cost, wide and easy accessibility, social support and motivation enhancement, flexibility in scheduling and location, diverse resources, possibility of receiving feedback, adaptability to different profiles and needs, continuity, and intervention monitoring, among others.Acquired brain injury (ABI) is a prevalent disorder in the population, characterized by the presence of impairments in executive functions that can become greatly disabling, hence there is a need for highly effective treatments. The following intervention proposal aims to use tools and resources available on the Facebook platform to create a series of tasks that complement the process-based neuropsychological rehabilitation program for this type of patients. The general objective of this proposal is to design, implement and test the effectiveness of an intervention program based on cognitive training through the use of Facebook, in order to improve executive deficits present in patients with ABI. In addition, we will study the potential effects on memory functions and social skills. To achieve this, 24 patients will be recruited to participate in a 9-session treatment, and will be evenly divided into two groups, either the experimental or the control. Following the intervention, even though each group is expected to present enhancements in the assessed executive sub- processes (cognitive flexibility, attentional control, goal setting and information processing), we anticipate significant differences between them. In this way, the experimental group will show a significant improvement in executive functioning in addition to an increase in social skills and memory. This approach represents important and innovative implications for future research compared to other well-established procedures, as it offers numerous advantages, such as low cost, wide and easy accessibility, social support and motivation enhancement, flexibility in scheduling and location, diverse resources, possibility of receiving feedback, adaptability to different profiles and needs, continuity, and intervention monitoring, among others

Relic Neutralino Density in Scenarios with Intermediate Unification Scale

We analyse the relic neutralino density in supersymmetric models with an intermediate unification scale. In particular, we present concrete cosmological scenarios where the reheating temperature is as small as $\cal{O}$ $1 - 1000$ MeV). When this temperature is associated to the decay of moduli fields producing neutralinos, we show that the relic abundance increases considerably with respect to the standard thermal production. Thus the neutralino becomes a good dark matter candidate with 0.1\lsim \Omega h^2 \lsim 0.3, even for regions of the parameter space where large neutralino-nucleon cross sections, compatible with current dark matter experiments, are present. This is obtained for intermediate scales $M_I\sim 10^{11}-10^{14}$ GeV, and moduli masses $m_\phi\sim 100-1000$ GeV. On the other hand, when the above temperature is associated to the decay of an inflaton field, the relic abundance is too small.Comment: Latex, 11 pages, 2 figure

Direct detection of neutralino dark matter in supergravity

The direct detection of neutralino dark matter is analysed in general supergravity scenarios, where non-universal soft scalar and gaugino masses can be present. In particular, the theoretical predictions for the neutralino-nucleon cross section are studied and compared with the sensitivity of dark matter detectors. We take into account the most recent astrophysical and experimental constraints on the parameter space, including the current limit on B(Bs-> mu+ mu-). The latter puts severe limitations on the dark matter scattering cross section, ruling out most of the regions that would be within the reach of present experiments. We show how this constraint can be softened with the help of appropriate choices of non-universal parameters which increase the Higgsino composition of the lightest neutralino and minimise the chargino contribution to the b->s transition.Comment: 27 pages, 22 figure

New postcranial remains of large toxodontian notoungulates from the late Oligocene of Mendoza, Argentina and their systematic implications

During the last decade, the Deseadan (late Oligocene) Quebrada Fiera locality, Mendoza Province, Argentina, has provided a large amount of mammal remains. Taxonomic studies have shown the presence of faunal elements common with other Deseadan associations from Patagonia and lower latitudes (Salla, Bolivia), as well as endemic taxa of different groups of mammals (Notohippidae, Leontiniidae, Homalodotheriidae, Hegetotheriidae, and Metatheria) and even a gastropod. In this work, we present a taxonomic and phylogenetic analysis of a set of postcranial fossils of three families of the suborder Toxodontia (Notoungulata). The postcranial elements are assigned to taxa previously recognized at Quebrada Fiera, such as the leontiniid Gualta cuyana and the homalodotheriid Asmodeus petrasnerus, but also to the family Toxodontidae that is represented by Proadinotherium sp. and another larger toxodontid; a few dental remains of Proadinotherium are also included as this is the first time that toxodontids from Quebrada Fiera are described. In the case of A. petrasnerus, an almost complete calcaneum allows us to expand the diagnosis of this taxon. The bones assigned to G. cuyana enlarge the anatomical knowledge of this species. In turn, the presence of the genus Proadinotherium extends its geographic distribution in Argentina and adds to the extra-Patagonian record of P. saltoni from Salla, Bolivia. Phylogenetic results do not differ much from previous analyses using postcranial characters, and the obtained consensus trees show low node supports. The various phylogenetic analyses performed here provide a more robust framework to interpret the relationships of the studied taxa.Fil: Hernández del Pino, Santiago Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Seoane, Federico Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Cerdeño Serrano, Maria Esperanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentin