Signature of Nonadiabatic Coupling in Excited-State Vibrational Modes Soler Bastida, Miguel Ángel; Nelson, Tammie; Roitberg, Adrián; Tretiak, Sergei; Fernández Alberti, Sebastián Using analytical excited-state gradients, vibrational normal modes have been calculated at the minimum of the electronic excited-state potential energy surfaces for a set of extended conjugated molecules with different coupling between them. Molecular model systems composed of units of polyphenylene ethynylene (PPE), polyphenylenevinylene (PPV), and naphthacene/pentacene (NP) have been considered. In all cases except the NP model, the influence of the nonadiabatic coupling on the excited-state equilibrium normal modes is revealed as a unique highest frequency adiabatic vibrational mode that overlaps with the coupling vector. This feature is removed by using a locally diabatic representation in which the effect of NA interaction is removed. Comparison of the original adiabatic modes with a set of vibrational modes computed in the locally diabatic representation demonstrates that the effect of nonadiabaticity is confined to only a few modes. This suggests that the nonadiabatic character of a molecular system may be detected spectroscopically by identifying these unique state-specific high frequency vibrational modes.

Continuous phase estimation from noisy fringe patterns based on the implicit smoothing splines Wielgus, Maciek; Patorski, Krzysztof; Etchepareborda, Pablo Gonzalo; Federico, Roque Alejandro We introduce the algorithm for the direct phase estimation from the single noisy interferometric pattern. The method, named implicit smoothing spline (ISS), can be regarded as a formal generalization of the smoothing spline interpolation for the case when the interpolated data is given implicitly. We derive the necessary equations, discuss the properties of the method and address its application for the direct estimation of the continuous phase in both classical interferometry and digital speckle pattern interferometry (DSPI). The numerical illustrations of the algorithm performance are provided to corroborate the high quality of the results.

Deconvolution of isotope signals from bundles of multiple hairs Remien, Christopher H.; Adler, Frederick R.; Chesson, Lesley A.; Valenzuela, Luciano Oscar; Ehleringer, James R.; Cerling, Thure E. Segmental analysis of hair has been used in diverse fields ranging from forensics to ecology to measure the concentration of substances such as drugs and isotopes. Multiple hairs are typically combined into a bundle for segmental analysis to obtain a high-resolution series of measurements. Individual hair strands cycle through multiple phases of growth and grow at different rates when in the growth phase. Variation in growth of hair strands in a bundle can cause misalignment of substance concentration between hairs, attenuating the primary body signal. We developed a mathematical model based on the known physiology of hair growth to describe the signal averaging caused by bundling multiple hairs for segmental analysis. The model was used to form an inverse method to estimate the primary body signal from measurements of a hair bundle. The inverse method was applied to a previously described stable oxygen isotope chronology from the hair of a murder victim and provides a refined interpretation of the data. Aspects of the reconstruction were confirmed when the victim was later identified.

Celia Lapalma de Emery y la cuestión social desde una perspectiva católica en el temprano siglo XX argentino; Celia Lapalma de Emery and the Social Question from a Catholic View-point in the Early Twentieth Century Argentina Acha, José Omar El Estado argentino de inicios del siglo veinte se hallaba en un momento de consolidación y extensión en la sociedad en proceso de cambio. Uno de sus aspectos más relevantes consistió en el desarrollo de instrumentos y discursos para responder a la “cuestión social”. En este artículo se reconstruye la acción y opiniones de una inspectora del Departamento Nacional del Trabajo especializada en el trabajo femenino y activista católica, Celia Lapalma de Emery. Se muestra con ello las diferentes opciones culturales respecto del trabajo, y particularmente del trabajo femenino, en el seno de las instituciones estatales.; In the beginning of the XXth century the Argentinean State was consolidating and spreading its power on the changing society. One of the main aspects of its developments concerned the building of tools to answer to the so called “social question”. This article deals with the action and beliefs of an inspector of the National Labor Department, Celia Lapalma de Emery, who was specialized on feminine labor. In doing so it is demonstrated the different cultural perspectives regarding labor, particularly the feminine one, in the core of the state institutions.

Continuing impacts on red deer from a volcanic eruption in 2011 Fluck, Werner Thomas In June of 2011, the Puyehue–Cordon Caulle volcanic eruption deposited large amounts of ashes in Chile and Argentina. Although ashes were initially considered innoxious based on water leachates, we found clinical cases of fluoride intoxication in red deer (Cervus elaphus) and domestic herbivores in Argentina. The diagnosis was corroborated by high bone fluoride concentrations. The dynamics of temporal accumulation of fluoride suggested an average increase of 1,000 ppm per year of fluoride in the bone. However, a few deer had fluoride levels, suggesting an accumulation rate of about 3,700 ppm per year. Via recent sampling of deer, we now confirm that bone levels have reached up to 10,396 ppm of fluoride after about 28 months of exposure. Tephra across various sites averaged 548 ppm of fluoride, and due to dry conditions and eolic redeposition of ashes particularly east of the continental divide, clinical fluorosis is expected to continue to intensify. The described impact will reverberate through several aspects of the ecology of the deer, including effects on population dynamics, morbidity, predation susceptibility, as well as other components of the ecosystem, including other herbivores, scavengers, and plant communities.

Water and Membrane Dynamics in Suspensions of Lipid Vesicles Functionalized with Poly(ethylene glycol)s Clop, Eduardo Matias; Chattah, Ana Karina; Perillo, Maria Angelica The present work was aimed at studying the molecular dynamics at different levels of model membranes having a simulated glycoclix, with focus on the molecular crowding conditions at the lipid–water interfacial region. Thus, binary mixtures of dipalmitoylphosphatidylcholine (dpPC) and a poly(ethylene glycol) (PEGn) derivative of dipalmitoylphosphatidylethanolamine (PE) (where n = 350, 1000, and 5000, respectively, refer to PEG molecular masses) were submitted to 1H spin–lattice relaxation time (T1) and 31P NMR spectra analysis. 1H NMR relaxation times revealed two contributing components in each proton system (PEG, phospholipids, and water), for all the mixtures studied, exhibiting values of T1 with very different orders of magnitude. This allowed identifying confined and bulk water populations as well as PEG moieties becoming more disordered and independent from the phospholipid moiety as n increased. 31P spectra showed a typical broad bilayer signal for n = 350 and 1000, and an isotropic signal characteristic of micelles for n = 5000. Surface pressure (π)–molecular area isotherms and compressional modulus measurements provided further structural information. Moreover, epifluorescence microscopy data from monolayers at π ∼ 30 mN/m, the expected equilibrium π in lipid bilayers, allowed us to postulate that both 1H populations resolved through NMR in phospholipids and lipopolymers corresponded to different phase domains.

Elimination for generic sparse polynomial systems Herrero, Maria Isabel; Jeronimo, Gabriela Tali; Sabia, Juan Vicente Rafael We present a new probabilistic symbolic algorithm that, given a variety defined in an n-dimensional affine space by a generic sparse system with fixed supports, computes the Zariski closure of its projection to an ℓ-dimensional coordinate affine space with ℓ

Potencialidad hídrica de la región santafesina: el acuífero guaraní en el territorio provincial Méndez Zacarías, Jovita Soledad; Zimmermann, Erik Daniel En este trabajo se analiza la problemática del acceso al agua en localidades de la provincia de Santa Fe, revisando el historial del servicio de agua potable en la provincia en los últimos 30 años. El mismo está enmarcado por una carencia de políticas adecuadas donde se aborde de manera integral las problemáticas asociadas con el agua ( control de crecidas, saneamiento y provisión de agua potable). Se analiza la oferta hídrica tanto en lo referente a recursos superficiales como subterráneos, poniendo énfasis en las últimas investigaciones sobre la presencia del acuífero Guaraní en el territorio provincial. A excepción de las localidades que se abastecen del Río Paraná o algunos de sus brazos, el resto de las localidades se abastecen de aguas subterráneas (el 96% del total), y en general, el recurso no es apropiado para consumo humano y requiere costosos de tratamientos de potabilización. La excelente calidad del agua y la posibilidad de captación en el lugar, hacen que el aprovechamiento potencial del Acuífero Guaraní asuma características inigualables para el abastecimiento en nuestra región. Por otra parte, considerando la demanda actual de agua para consumo, no sólo en la provincia sino también en la región se deberá reflexionar sobre los usos para balneoterapia que se le está dando actualmente, sobreexplotando el acuífero y contaminando cuerpos receptores. Resulta imperioso que la legislación respecto a los usos y la protección del Acuífero Guaraní, sea elaborada de manera consensuada por los estados soberanos que comparten el recurso sin intervención alguna de países que son ajenos a los intereses de la región.; In this paper we analyze the problem of access to drinking water in towns in the province of Santa Fe, reviewing the history of drinking water service in the province in the last 30 years. The service is framed by inappropriate policies which can holistically addresses the problems associated with water (flood control, sanitation and water supply). Water resources is analyzed in terms of both surface and groundwater resources, with emphasis on the latest research on the Guarani Aquifer presence in the province. Except for the towns that are supplied by Paraná River or some of its tributaries, the remaining localities have groundwater supply (96% of total), and in general, the resource is not suitable for human consumption and requires expensive water treatment. The excellent water quality and the ability to capture in place, make the potential use of the Guarani Aquifer assume excellent features for supply in our region. Moreover, considering the current demand for drinking water, not only in the province but also in the región, must reflect on the uses for balneotherapy currently being given. It is imperative that the legislation regarding the use and protection of the Guarani Aquifer, is made by consensus by the sovereign states sharing the resource without any intervention from countries that are outside to the interests of the region.

Acidic preconditioning improves the proangiogenic responses of endothelial colony forming cells Mena, Hebe Agustina; Lokajczyk, Anna; Dizier, Blandine; Strier, Sergio E.; Voto, Liliana S.; Boisson Vidal, Catherine; Schattner, Mirta Ana; Negrotto, Soledad Objective: Acidosis is present in several pathological conditions where vasculogenesis takes place including ischemia, tumor growth and wound healing. We have previously demonstrated that acidosis induces human CD34+ cell apoptosis. Considering that endothelial colony-forming cells (ECFC) are a subpopulation of CD34+ cells and key players in vasculogenesis, in the present study we investigated the effect of acidosis on the survival and functionality of ECFC. Approach and results: Endothelial colony-forming cells obtained by differentiation of human cord blood CD34+ cells in endothelial growth medium-2 for 14–21 days were exposed at pH 7.4, 7.0 or 6.6. We found that acidosis failed to induce ECFC apoptosis and, although an early reduction in proliferation, chemotaxis, wound healing and capillary-like tubule formation was observed, once the medium pH was restored to 7.4, ECFC proliferation and tubulogenesis were augmented. Stromal cell derived factor-1 (SDF1)-driven migration and chemokine receptor type 4 surface expression were also increased. The maximal proangiogenic effect exerted by acidic preconditioning was observed after 6 h at pH 6.6. Furthermore, preconditioned ECFC showed an increased ability to promote tissue revascularization in a murine model of hind limb ischemia. Immunoblotting assays showed that acidosis activated AKT and ERK1/2 and inhibited p38 pathways. Proliferation rises triggered by acidic preconditioning were no longer observed after AKT or ERK1/2 inhibition, whereas p38 suppression not only mimicked but also potentiated the effect of acidosis on ECFC tubule formation abilities. Conclusions: These results demonstrate that acidic preconditioning greatly increases ECFC-mediated angiogenesis in vitro including ECFC proliferation, tubulogenesis and SDF1-driven chemotaxis and is a positive regulator of microvessel formation in vivo.

Genetic and evolutionary characterization of Venezuelan equine encephalitis virus isolates from Argentina Pisano, María Belén; Torres, Carolina; Ré, Viviana Elizabeth; Farías, Adrián Alejandro; Sánchez Seco, María Paz; Tenorio, Antonio; Campos, Rodolfo Hector; Contigiania, Marta Silvia Venezuelan equine encephalitis viruses (VEEV) are emerging pathogens of medical and veterinary importance circulating in America. Argentina is a country free from epizootic VEEV activity, with circulation of enzootic strains belonging to Rio Negro virus (RNV; VEEV subtype VI) and Pixuna virus (PIXV, VEEV subtype IV). In this work, we aim to report the sequencing and phylogenetic analyses of all Argentinean VEE viruses, including 7 strains previously isolated from mosquitoes in 1980, 5 sequences obtained from rodents in 1991 and 11 sequences amplified from mosquitoes between 2003 and 2005. Two genomic regions, corresponding to the non-structural protein 4 (nsP4) and the protein E3/E2 (PE2) genes were analyzed, but only 8 samples could be amplified in the last one (longer and more variable fragment of 702 bp). For both genomic fragments, phylogenetic trees showed the absence of lineages within RNV group, and a close genetic relationship between Argentinean strains and the prototype strain BeAr35645 for PIXV clade. The analysis of nsP4 gene opens the possibility to propose a possible geographic clustering of strains within PIXV group (Argentina and Brazil). Coalescent analysis performed on RNV sequences suggested a common ancestor of 58.3 years (with a 95% highest posterior density [HPD] interval of 16.4–345.7) prior to 1991 and inferred a substitution rate of 9.8 × 10−5 substitutions/site/year, slightly lower than other enzootic VEE viruses. These results provide, for the first time, information about genetic features and variability of all VEEVs detected in Argentina, creating a database that will be useful for future detections in our country. This is particularly important for RNV, which has indigenous circulation.

Batrachochytrium dendrobatidis infecting anurans in a protected area from Santa Fe province, Argentina Ghirardi, Romina; Levy, Michael G.; Lopez, Javier Alejandro; Steciow, Monica Mirta; Perotti, Maria Gabriela The finding of anurans infected with Bd in a protected area in the floodplain of Paraná river makes imperative alert environmental authorities to take the necessary actions to evaluate the presence of the chytrid fungus in all species inhabiting islands of the PNISF. It is compulsory to take precautions to avoid the diffusion of this dangerous pathogen (Federici et al., 2008). In particular, rangers patrol in PNISF or scientist studying in the area should pay special attention not to transfer the zoospores from site to site, using different tools or disinfecting them accurately before moving between sites (see Livo, 2004 and Perotti y Ghirardi, 2010). Further environmental monitoring, combined with proper methods of quarantine and pathogen elimination are badly needed to guarantee amphibian survival and to prevent the spread of chytridiomycosis in this recently created protected area.

Vanadium and cancer treatment: Antitumoral mechanisms of three oxidovanadium(IV) complexes on a human osteosarcoma cell line Leon, Ignacio Esteban; Butenko, N.; Di Virgilio, Ana Laura; Muglia, Cecilia Isabel; Baran, Enrique José; Cavaco, I.; Etcheverry, Susana Beatriz We report herein the antitumor actions of three oxidovanadium(IV) complexes on MG-63 human osteosarcoma cell line. The three complexes: VO(oda), VO(oda)bipy and VO(oda)phen (oda = oxodiacetate), caused a concentration dependent inhibition of cell viability. The antiproliferative action of VO(oda)phen could be observed in the whole range of concentrations (at 2.5 μM), while VO(oda)bipy and VO(oda) showed a decrease of cell viability only at higher concentrations (at 50 and 75 μM, respectively) (p < 0.01). Moreover, VO(oda)phen caused a decrease of lysosomal and mitochondrial activities at 2.5 μM, while VO(oda) and VO(oda)bipy affected neutral red uptake and mitochondrial metabolism at 50 μM (p < 0.01). On the other hand, no DNA damage studied by the Comet assay could be observed in MG-63 cells treated with VO(oda) at 2.5–10 μM. Nevertheless, VO(oda)phen and VO(oda)bipy induced DNA damage at 2.5 and 10 μM, respectively (p < 0.01). The generation of reactive oxygen species increased at 10 μM of VO(oda)phen and only at 100 μM of VO(oda) and VO(oda)bipy (p < 0.01). Besides, VO(oda)phen and VO(oda)bipy triggered apoptosis as determined by externalization of the phosphatidylserine. The determination of DNA cleavage by agarose gel electrophoresis showed that the ability of VO(oda)(bipy) is similar to that of VO(oda), while VO(oda)(phen) showed the highest nuclease activity in this series. Overall, our results showed a good relationship between the bioactivity of the complexes and their structures since VO(oda)phen presented the most potent antitumor action in human osteosarcoma cells followed by VO(oda)bipy and then by VO(oda) according to the number of intercalating heterocyclic moieties.

Molecules, dust, and protostars in NGC 3503 Duronea, Nicolas Urbano; Vasquez, Javier; Barba, Rodolfo Hector; Romero, G.; Cappa, Cristina Elisabeth; Bronfman, L. Aims: We present here a follow-up study of the molecular gas and dust in the environs of the star forming region NGC 3503. This study aims at dealing with the interaction of the Hii region NGC 3503 with its parental molecular cloud, and also with the star formation in the region, that was possibly triggered by the expansion of the ionization front against the parental cloud. Methods: To analyze the molecular gas we use CO(J = 2 → 1), 13CO(J = 2 → 1), C18O(J = 2 → 1), and HCN(J = 3 → 2) line data obtained with the on-the-fly technique from the APEX telescope. To study the distribution of the dust, we make use of unpublished images at 870 μm from the ATLASGAL survey and IRAC-GLIMPSE archival images. We use public 2MASS and WISE data to search for infrared candidate young stellar objects (YSOs) in the region. Results: The new APEX observations allowed the substructure of the molecular gas in the velocity range from ~-28 km s-1 to -23 km s-1 to be imaged in detail. The morphology of the molecular gas close to the nebula, the location of the PDR, and the shape of radio continuum emission suggest that the ionized gas is expanding against its parental cloud, and confirm the champagne flow scenario. We have identified several molecular clumps and determined some of their physical and dynamical properties such as density, excitation temperature, mass, and line width. Clumps adjacent to the ionization front are expected to be affected by the Hii region, unlike those that are distant from it. We have compared the physical properties of the two kinds of clumps to investigate how the molecular gas has been affected by the Hii region. Clumps adjacent to the ionization fronts of NGC 3503 and/or the bright rimmed cloud SFO 62 have been heated and compressed by the ionized gas, but their line width is not different from those that are too distant from the ionization fronts. We identified several candidate YSOs in the region. Their spatial distribution suggests that stellar formation might have been boosted by the expansion of the nebula. We discard the collect-and-collapse scenario and propose alternative mechanisms such as radiatively driven implosion on pre-existing molecular clumps or small-scale Jeans gravitational instabilities.

Molecular chaperone activity and biological regulatory actions of the TPR-domain immunophilins FKBP51 and FKBP52 Erlejman, Alejandra Giselle; Lagadari, Mariana; Harris, Diondra C.; Cox, Marc B.; Galigniana, Mario Daniel Immunophilins comprise a family of intracellular proteins with peptidyl-prolyl-(cis/trans)-isomerase activity. These foldases are abundant, ubiquitous, and able to bind immunosuppressant drugs, from which the term immunophilin derives. Family members are found in abundance in virtually all organisms and subcellular compartments, and their amino acid sequences are conserved phylogenetically. Immunophilins possess the ability to function as molecular chaperones favoring the proper folding and biological regulation of their biological actions. Their ability to interact via their TPR domains with the 90-kDa heat-shock protein, and through this chaperone, with several signalling cascade factors is of particular importance. Among the family members, the highly homologous proteins FKBP51 and FKBP52 were first characterized due to their ability to interact with steroid hormone receptors. Since then, much progress has been made in understanding the mechanisms by which they regulate receptor signaling and the resulting roles they play not only in endocrine processes, but also in cell architecture, neurodifferentiation, and tumor progression. In this article we review the most relevant features of these two immunophilins and their potential as pharmacologic targets.

Metabolic level recognition of progesterone in dairy Holstein cows using probabilistic models Turino, Ludmila Noelia; Cristaldi, Mariano Daniel; Mariano, Rodolfo Nicolás; Boimvaser, Sonia; Scandolo, D. E. Administration of exogenous progesterone is widely used in hormonal protocols for estrous (re)synchronization of dairy cattle without regarding pharmacological issues for dose calculation. This happens because it is difficult to estimate the metabolic level of progesterone for each individual cow before administration. In the present contribution, progesterone pharmacokinetics has been determined in lactating Holstein cows with different milk production yields. A Bayesian approach has been implemented to build two probabilistic progesterone pharmacokinetic models for high and low yield dairy cows. Such models are based on a one-compartment Hill structure. Posterior probabilistic models have been structurally set up and parametric probability density functions have been empirically estimated. Moreover, a global sensitivity analysis has been done to know sensitivity profile of each model. Finally, posterior probabilistic models have adequately recognized cow´s progesterone metabolic level in a validation set when Kullback-Leibler based indices were used. These results suggest that milk yield may be a good index for estimating pharmacokinetic level of progesterone.

Solar dryer efficiency considering the total drying potential. Application of this potential as a resource indicator in north-western Argentina Altobelli, Fabiana Noelia; Condori, Miguel Angel; Durán, Gonzalo José; Martinez, C. Indicators of drying potential for a region based on a model of free water evaporation in a solar dryer are presented. In these indicators, the total solar radiation and the saturation deficit of ambient air are considered as driving forces for solar drying process. The indicators were used to define the solar dryer performance considering the drying potential of the site. The performance definition was applied to a forced solar dryer placed in the town of San Carlos, (Salta, north-western Argentina) and was loaded with 30 kg of trays filled with water. The results were compared with other performance definitions. A standard dryer of 0.1 kg s−1 airflow was defined to estimate the potential indicators for 18 locations of the north-western Argentina using daily historical data. A mapping of dryer potential was obtained for the entire region through interpolating of results, showing similarity in relation to the distribution of phytogeographic areas. September was the month with the highest potential for solar drying on account of the end of the dried season and the influence of the local warm wind. The indicators also were obtained for San Carlos using recently measured data. Deviations from these potentials with respect to those obtained from the historical database were analyzed and similar results were obtained. The usefulness of these indicators was showed as a tool to be considered when variables other than solar radiation – such as temperature and relative humidity – are taken as energy sources.

Environmental modulation of the plankton community composition and size-structure along the eutrophic intertidal coast of the Río de la Plata estuary, Argentina Garcia, Maximiliano Darío; Bonel, Nicolás In this study we investigated the spatial distribution of the plankton community, bacterio-, phyto-, and zooplankton, in relation with environmental conditions along the intertidal coast of the Río de la Plata estuary, Argentina. Plankton was analyzed in terms of species composition, abundance, biomass (carbon content), and size-structure. We aim to evaluate the potential effects of anthropogenic impacts (e.g., nutrient enrichment) and physicochemical gradients alongshore (e.g., salinity, turbidity) on the composition and functioning of the plankton. We asked whether the natural structuring of the plankton by salinity and turbidity, known to be true of estuaries, is modified by eutrophication along the studied shoreline. We found that the density and biomass of bacteria and phytoplankton were strikingly enhanced by high eutrophication levels along the intertidal southwest coast of the Río de la Plata estuary. We also found that the highest zooplankton density in the most polluted area but the biomass showed a different distribution pattern. Nevertheless, when zooplankton was analyzed by means of its size fraction, we accordingly found that the microzooplankton biomass was positively associated with smaller-size phytoplankton groups and the most polluted study sites. Copepods were the major taxonomic groups that best represented the mesozooplankton biomass. We therefore expected that its distribution was modulated by the presence of its food items (i.e., large cells) which, in turn, were more abundant in the middle-outer zone. In contrast, we found that the highest biomass of copepods occurred at the innermost site of the estuary and we found no significant association with other planktonic groups. Overall, this study highlights the noteworthy impacts of human activities modifying the functioning of this coastal ecosystem. The differences found in the taxonomic composition and size structure of the planktonic community assemblage between the most polluted and less polluted sites constitutes excellent baseline for considering plankton as ecological an indicator of water quality.

Role of basin width variation in tectonic inversion: insight from analogue modelling and implications for the tectonic inversion of the Abanico Basin, 328–348S, Central Andes Jara, P.; Likerman, Jeremias; Winocur, Diego Alejandro; Ghiglione, Matias; Cristallini, Ernesto Osvaldo; Pinto, L.; Charrier, R. We use analogue modelling to investigate the response of compressional deformation superimposed on an extensional basin with along-strike changes in width. Parameters described include extension and shortening distribution and directions, orientation of structures and degree of basin inversion. Two types of model are presented: in the first (Type I), an extensional basin is constructed with variable width (applying differential extension) and subsequently inverted by homogeneous shortening; in the second (Type II), an extensional basin with constant width is subsequently inverted by inhomogeneous shortening (differential compression). From our observations, we compare both types of model to structural patterns observed in some natural cases from the Central Andes. Both models generate oblique structures, but in the Type II model a significant rotation is characteristic. Our results suggest that in the Central Andes region between 32° and 33°S, the Abanico Basin may correspond to a basin of smaller area compared to the larger basin south of 33°S. Our Type I model further explains some patterns observed there, from which we conclude that the control exercised by the width of a pre-existing basin should be considered when interpreting the geological evolution of that area of the Andes.

Phylogeny of New World Paspalum (Poaceae, Panicoideae, Paspaleae) based on plastid and nuclear markers Scataglini, María Amalia; Zuloaga, Fernando Omar; Giussani, Liliana Mónica; Denham, Silvia Suyai; Morrone, Osvaldo Phylogenetic analyses of 131 terminals of Paspalum and related genera, based on both plastid and nuclear markers, were performed under maximum parsimony and Bayesian methods. The total evidence analyses generated a hypothesis showing that Paspalum would be monophyletic if Spheneria, Thrasyopsis and Reimarochloa are included within the genus. Paspalum inaequivalve and P. microstachyum, two species of the Inaequivalvia group were related to genus Anthaenantiopsis, excluded from Paspalum, or nested within it by plastid and nuclear markers, respectively. Subgenera Anachyris and Harpostachys were partially recovered as monophyletic assemblages, while subg. Ceresia and Paspalum resolved as polyphyletic. Within subgenus Paspalum, some informal groups were recovered as monophyletic, while others were resolved as paraphyletic or polyphyletic. Phylogenetic relationships among species of Paspalum were partially recovered possibly due to reticulation events among species, autopolyploidization and apomixis; all these processes being common in Paspalum, thus obscuring the infrageneric classification.

Traveling planetary wave ionospheric disturbances and their role in the generation of equatorial spread-F and GPS phase fluctuations during the last extreme low solar activity and comparison with high solar activity de Abreu, A. J.; Fagundes, P. R.; Bolzan, M. J. A.; Gende, Mauricio Alfredo; Brunini, Claudio Antonio; de Jesus, R.; Pillat, V. G.; Abalde, J. R.; Lima, W. L. C. This investigation studies traveling planetary wave ionospheric disturbance (TPWID) type oscillations on the modulation of the F region virtual height rise during the EB electric field pre-reversal enhancement (PRE), near sunset hours. We also studied their role in the generation of equatorial spread F (ESF) and GPS phase fluctuations during periods of the last extreme low solar activity (LSA) of January 2009 to April 2010 ðF10:7 ¼73Þ. A comparison ismadewith periods of high solar activity (HSA) in 2003 and 2004 near equatorial region. The ionospheric irregularities investigated are medium (bottom-side) and large (plasma bubble) scales. Ionospheric F region oscillations with period of days are due to the TPWIDs, which play an important role in producing favorable or unfavorable conditions for equatorial ionospheric irregularities, changing the electron vertical profile and F region height. In this paper, we present simultaneous ionospheric sounding (ionosonde) and GPS vertical total electron content (vTEC) observations carried out near equatorial region (Palmas 10.21S, 48.21W) and lowlatitude region (São José dos Campos 23.21S, 45.91W; located under the southern crest of the equatorial ionospheric anomaly), Brazil. Observations show that the occurrence of fresh ESF during LSA and HSA and fresh GPS phase fluctuations at equatorial region follow the trend of day-to-day variations in the F region virtual height, which are due to electric field PREmodulated by TPWID wave like oscillations. During LSA, the altitude of 250 km acts as a threshold height for the generation of fresh ionospheric irregularities, whereas during HSA, the threshold height is 300 km. The observations also found a strong increase in the generation of fresh ionospheric irregularities from October 2009 to March 2010 during LSA and from September 2003 to March 2004 during the HSA. Furthermore, in LSA, the period of fresh ionospheric irregularities was less than during HSA, though both periods followed a similar seasonal pattern. In the low- latitude, we observed more ESFs than phase fluctuations because ionosonde is more sensitive than GPS. We also observed periodswith and without day-to-day oscillations in the F region virtual height. The observations made by GPS stations and ionosondes in the equatorial region, for much of the period analyzed, presented similar results with regard to the generation of equatorial ionospheric irregularities. In the low latitude, some nights of January, February, October, and December 2009 also showed a similarity.