First detection of hepatitis E virus in Central Argentina: Environmental and serological survey Martinez Wassaf, Maribel Graciela; Pisano, María Belén; Barril, Patricia Angelica; Elbarcha, Osvaldo C.; Pinto, Marcelo A.; Oliveira, Jaqueline Mendes de; DiGiusto, Pablo; Nates, Silvia Viviana; Ré, Viviana Elizabeth Background: The hepatitis E virus (HEV) is an emergent causative agent of acute hepatitis worldwide, transmitted by fecal-oral route. In Argentina it is considered rare, so differential laboratory testing is not routinely performed. Besides, in Argentina's central area epidemiological and molecular characteristics of HEV are still unknown. Objectives: Provide evidence of local circulation of HEV by molecular detection on environmental samples and by serological survey in healthy adult population of Córdoba city, Argentina. Study design: Environmental surveillance was conducted in river and sewage samples collected between 2007 and 2009–2011. Viral detection was performed by RT-Nested PCR of ORF-1 and ORF-2 partial regions. Anti-HEV IgG was determined by EIA in 433 serum samples collected between 2009 and 2010. Results: HEV was detected in 6.3% of raw sewage samples and in 3.2% of riverine samples. Nucleotide sequencing analyses revealed that all isolates belonged to genotype 3, subtypes a, b and c. The prevalence of IgG anti-HEV was 4.4%. Seroprevalence increased with the age of the individuals (OR: 3.50; 95% CI 1.39–8.87; p = 0.0065) and, although the prevalence was higher in low income population, no statistical relation was found between anti-HEV and socioeconomic level. Conclusions: The environmental findings added to serological results, demonstrate that HEV circulates in central Argentina. Contamination of water with HEV could represent a route of transmission for local populations, which have a high number of susceptible individuals. This fact alerts local health care systems in order to include detection of HEV in the diagnostic algorithm of viral hepatitis.

Increment of the collective pinning energy in Na1 − xCa x Fe2As2 single crystals with random point defects introduced by proton irradiation Haberkorn, Nestor Fabian; Kim, Jeehoon; Maiorov, B.; Usov, I.; Chen, G. F.; Yu, W.; Civale, L. We study the influence of random point defects introduced by 3 MeV proton irradiation (doses 1 × 1016 and 2 × 1016 cm2) on the vortex dynamics of Na x Ca1 − xFe2As2 (x = 0.5 and x = 0.75) single crystals. Our results indicate that the irradiation produces an enhancement of the critical current density and a reduction of the creep rate in vortex relaxation. The plateau in the temperature dependence of vortex creep rate initially present in as-grown single crystals disappears after irradiation. This fact can be associated with a large increment of the collective pinning energy (from <100 to 350–400 K). On the other hand, Maley analysis indicates that after irradiation both samples present a glassy exponent μ close to the one expected in the so-called large bundle regime (μ ≈ 7/9) for random point defects.

Memory beyond expression Delorenzi, Alejandro; Maza, Francisco Javier; Suárez, Luis Daniel; Barreiro, Karina Andrea; Molina, Víctor Alejandro; Stehberg. J. The idea that memories are not invariable after the consolidation process has led to new perspectives about several mnemonic processes. In this framework, we review our studies on the modulation of memory expression during reconsolidation. We propose that during both memory consolidation and reconsolidation, neuromodulators can determine the probability of the memory trace to guide behavior, i.e. they can either increase or decrease its behavioral expressibility without affecting the potential of persistent memories to be activated and become labile. Our hypothesis is based on the findings that positive modulation of memory expression during reconsolidation occurs even if memories are behaviorally unexpressed. This review discusses the original approach taken in the studies of the crab Neohelice (Chasmagnathus) granulata, which was then successfully applied to test the hypothesis in rodent fear memory. Data presented offers a new way of thinking about both weak trainings and experimental amnesia: memory retrieval can be dissociated from memory expression. Furthermore, the strategy presented here allowed us to show in human declarative memory that the periods in which long-term memory can be activated and become labile during reconsolidation exceeds the periods in which that memory is expressed, providing direct evidence that conscious access to memory is not needed for reconsolidation. Specific controls based on the constraints of reminders to trigger reconsolidation allow us to distinguish between obliterated and unexpressed but activated long-term memories after amnesic treatments, weak trainings and forgetting. In the hypothesis discussed, memory expressibility – the outcome of experience-dependent changes in the potential to behave – is considered as a flexible and modulable attribute of long-term memories. Expression seems to be just one of the possible fates of re-activated memories.

Experimental in vitro infection of rat osteoblasts with measles virus stimulates osteogenic differentiation Ayala Peña, Victoria Belen; Santillán, Graciela Edith; Scolaro, Luis Alberto In this work we characterized the infection of a primary culture of rat osteoblastic lineage cells (OBCs) with measles virus (MeV) and the effect of infection on cell differentiation and maturation. Infection of OBCs with MeV led to high titers of infectivity released early after infection. Also, analysis of mRNAs corresponding to osteogenic differentiation markers like alkaline phosphatase (ALP), bone sialo-protein (BSP) and bone morphogenetic proteins (BMPs) 1-4-5-7 in OBCs revealed higher values (2–75-fold of increment) for infected cells in comparison with uninfected controls. Differentiation of OBCs in osteogenic medium prior to infection influenced the level of stimulation induced by MeV. Furthermore, treatment of OBCs with Ly294002, a PI3K/AKT inhibitor, increased viral titers, whereas treatment with 10 μM or 100 μM ATPγS diminished MeV multiplication. In addition, increments of osteogenic differentiation markers induced by MeV infection were not modified either by treatment with Ly294002 or ATPγS. These data provide the first evidence demonstrating that MeV can infect osteoblasts in vitro leading to osteoblastic differentiation, a key feature in bone pathogenic processes like otosclerosis.

Satisfaction, professional mobility and leadership in academic-scientific organisations Aparicio, Miriam Teresita The research work has been done in the field of social and organizational psychology. It is aim to analyze the factors which influence the levels of satisfaction and achievement reached by those working for scientific organizations and their relationship with professional mobility (Andrews, Aichholzer, Cole, Mittermeir, Stole-Heiskanen, UNESCO—United Nations Educational, Scientific and Cultural Organization, 1971) [1]. A stratified sample was taken from universities and different disciplines, based on a population of teachers from the Cuyo region (N = 355 R + D—Research & Development Units) (5% error margin). At this first stage, the research teachers were from Universidad Nacional de Cuyo (N = 53 Research Units): one chief or director and members. Quantitative techniques were used (two questionnaires). The results show that researchers’ satisfaction at different levels is connected with professional mobility and disciplinary fields. Regarding leadership, and considering professional mobility, a general feeling of satisfaction emerges among researchers, regardless of their disciplinary field.

Simultaneous pyometra and viable puppies’ gestation in a bitch Risso, Analia Lorena; Pellegrino, Francisco Javier; Corrada, Yanina Alejandra Here we describe a case of pyometra coexisting with gestation in a 4.5 year-old miniature short-haired Dachshund. The dog exhibited depression, vaginal discharge, polydipsia and dehydration. Ultrasound examination revealed the presence of low to moderate anechoic fluid collection in the left uterine horn. Blood analysis revealed mild neutrophilia with a left shift. Based on these findings a presumptive diagnosis of pyometra was made and the bitch was treated using amoxicillin-clavulanate with dopaminergic agonist (cabergoline). A second ultrasound scan revealed the presence of two gestational vesicles in the right uterine horn that were successfully carried to term. Unusually, while pyometra persisted in the left uterine horn, two viable puppies were delivered by caesarean section from the right uterine horn.

Amino acid metabolism conflicts with protein diversity Krick, Teresa Elena Genoveva; Verstraete, Nina; Alonso, Leonardo Gabriel; Shub, David A.; Ferreiro, Diego; Shub, Michael Ira; Sánchez Miguel, Ignacio Enrique The 20 protein-coding amino acids are found in proteomes with different relative abundances. The most abundant amino acid, leucine, is nearly an order of magnitude more prevalent than the least abundant amino acid, cysteine. Amino acid metabolic costs differ similarly, constraining their incorporation into proteins. On the other hand, a diverse set of protein sequences is necessary to build functional proteomes. Here, we present a simple model for a cost-diversity trade-off postulating that natural proteomes minimize amino acid metabolic flux while maximizing sequence entropy. The model explains the relative abundances of amino acids across a diverse set of proteomes. We found that the data are remarkably well explained when the cost function accounts for amino acid chemical decay. More than 100 organisms reach comparable solutions to the trade-off by different combinations of proteome cost and sequence diversity. Quantifying the interplay between proteome size and entropy shows that proteomes can get optimally large and diverse.

Hyphoderma romeroae sp. nov., a valid name for “Mutatoderma brunneocontextum” (Basidiomycota, Polyporales) Baltazar, Juliano M.; Rajchenberg, Mario Hyphoderma romeroae sp. nov. es propuesto para la especie “Mutatoderma brunneocontextum” C.E. Gómez que fuera inválidamente publicada previamente.; Hyphoderma romeroae sp. nov. is proposed for the species previously invalidly named as “Mutatoderma brunneocontextum” C.E. Gómez.

Numerical Simulations of Stick Percolation: Application to the Study of Structured Magnetorheological Elastomers Mietta, J. L.; Negri, Ricardo Martin; Tamborenea, Pablo Ignacio In this article we explore how structural parameters of composites filled with one-dimensional, electrically conducting elements (such as sticks, needles, chains, or rods) affect the percolation properties of the system. To this end, we perform Monte Carlo simulations of asymmetric two-dimensional stick systems with anisotropic alignments. We compute the percolation probability functions in the direction of preferential orientation of the percolating objects and in the orthogonal direction, as functions of the experimental structural parameters. Among these, we considered the average length of the sticks, the standard deviation of the length distribution, and the standard deviation of the angular distribution. We developed a computer algorithm capable of reproducing and verifying known theoretical results for isotropic networks and which allows us to go beyond and study anisotropic systems of experimental interest. Our research shows that the total electrical anisotropy, considered as a direct consequence of the percolation anisotropy, depends mainly on the standard deviation of the angular distribution and on the average length of the sticks. A conclusion of practical interest is that we find that there is a wide and well-defined range of values for the mentioned parameters for which it is possible to obtain reliable anisotropic percolation under relatively accessible experimental conditions when considering composites formed by dispersions of sticks, oriented in elastomeric matrices.

UV–Vis spectroscopic study and DFT calculation on the solvent effect of trimethoprim in neat solvents and aqueous mixtures Almandoz, M. C.; Sancho, Matias Israel; Duchowicz, Pablo Román; Blanco, Sonia Encarnacion The solvatochromic behavior of trimethoprim (TMP) was analyzed using UV–Vis spectroscopy and DFT methods in neat and binary aqueous solvent mixtures. The effects of solvent dipolarity/polarizability and solvent–solute hydrogen bonding interactions on the absorption maxima were evaluated by means of the linear solvation energy relationship concept of Kamlet and Taft. This analysis indicated that both interactions play an important role in the position of the absorption maxima in neat solvents. The simulated absorption spectra of TMP and TMP:(solvent)n complexes in ACN and H2O using TD-DFT methods were in agreement with the experimental ones. Binary aqueous mixtures containing as co-solvents DMSO, ACN and EtOH were studied. Preferential solvation was detected as a nonideal behavior of the wavenumber curve respective to the analytical mole fraction of co-solvent in all binary systems. TMP molecules were preferentially solvated by the organic solvent over the whole composition range. Index of preferential solvation, as well as the influence of solvent parameters were calculated as a function of solvent composition.

Cooperativity to increase Turing Pattern space for synthetic biology Diambra, Luis Anibal; Senthivel, Vivek Raj; Barcena Menendez, Diego; Isalan, Mark It is hard to bridge the gap between mathematical formulations and biological implementations of Turing patterns, yet this is necessary for both understanding and engineering these networks with synthetic biology approaches. Here, we model a reaction–diffusion system with two morphogens in a monostable regime, inspired by components that we recently described in a synthetic biology study in mammalian cells.1 The model employs a single promoter to express both the activator and inhibitor genes and produces Turing patterns over large regions of parameter space, using biologically interpretable Hill function reactions. We applied a stability analysis and identified rules for choosing biologically tunable parameter relationships to increase the likelihood of successful patterning. We show how to control Turing pattern sizes and time evolution by manipulating the values for production and degradation relationships. More importantly, our analysis predicts that steep dose–response functions arising from cooperativity are mandatory for Turing patterns. Greater steepness increases parameter space and even reduces the requirement for differential diffusion between activator and inhibitor. These results demonstrate some of the limitations of linear scenarios for reaction–diffusion systems and will help to guide projects to engineer synthetic Turing patterns.

Efecto de la precipitación sobre la dinámica hidrológica de las lagunas de la cuenca inferior del Río Colorado (período 1981-2011) Aliaga, Vanina Solange; Bohn, Vanesa Yael; Piccolo, Maria Cintia; Perillo, Gerardo Miguel E. The purpose of this study was to analyze the temporal dynamics of shallow lakes during the 2002-2012 years in the Colorado River Basin in relation to climate variability. Dry and humid periods were identified by water balance. Moreover, the influence of the extreme rainfall events on the shallow lakes in the region was analyzed. Shallow lakes area was estimated during three different years by satellite image processing (LANDSAT 5TM y 7 ETM). Water bodies were classified according to geomorphological, hydrological and morphometric criteria during a normal period. According rainfall amounts, 2011, 2004 and 2008 were considered normal, wet and dry years, respectively. As a result, 15 (normal), 20 (wet), and 5 (dry) shallow lakes which covered an area of 13.05, 14.54, and 5.8 km2 respectively were detected. A correlation between the area covered by water and the annual precipitation was obtained in the study area. As a result of the clustering method application, 3 groups of water bodies were defined. The first included the biggest and permanent water bodies (area > 1.5 km2). Group 2 included salt shallow lakes which Total Maximum Length (TML) orientation was N-S. The remaining group was composed by lakes located in the wettest area of the basin with an E-W LMT orientation.

Phase and amplitude measurements for high bandwidth optical signals Bulus Rossini, Laureano Andrés; Costanzo Caso, Pablo Alejandro; Paulucci, Emanuel; Duchowicz, Ricardo; Sicre, Enrique Eduardo In this paper a novel technique for obtaining the amplitude and phase of optical pulses with time extents as short as tens of ps is presented. The method which is based on the transport-of-intensity equation only requires, for a practical realization, of passive fiber optic devices. It employs as the main component a dispersive element with a known second order dispersion coefficient. Two different setup implementations are considered, for which simulations are carried out in order to test the method performance taking into account both, realizable models of the involved devices and typical pulses found in optical transmission systems. The characterization of optical pulses affected by dispersion and nonlinear effects, such as self-phase modulation, is used to evaluate the performance of the method and show the practical feasibility of the future implementation.

Nonlinear Control of a Buck Converter Feeding a Constant Power Load Solsona, Jorge Alberto; Gómez Jorge, Sebastián; Busada, Claudio In this paper a nonlinear control strategy for controlling a dc/dc Buck converter feeding a constant power load is proposed. A feedback controller is combined with a feedforward strategy. A nonlinear reduced order observer is used for estimating the value of the power load and its time derivative. These estimated values are fed forward to the nonlinear feedback controller whose design is based on feedback linearization method. The proposed controller is tested via simulations and also, experimental results are presented.

Measurement of cooling and warming rates in vitrification-based plant cryopreservation protocols Schneider Teixeira, Aline; Gonzalez Benito, M. Elena; Molina García, Antonio D. Cryopreservation protocols include the use of additives and pre-treatments aimed to reduce the probability of ice nucleation at all temperatures, mainly through micro-viscosity increase. Still, there is a risk of ice formation in the temperature region comprised between the equilibrium freezing (Tf) and the glass transition (TG) temperatures. Consequently, fast cooling and warming, especially in this region, is a must to avoid ice-derived damage. Vitrification and droplet-vitrification techniques, frequently used cryopreservation protocols based in fast cooling, were studied, alongside with the corresponding warming procedures. A very fast data acquisition system, able to read very low temperatures, down to that of liquid nitrogen, was employed. Cooling rates, measured between -20 and -120 ºC, ranged from ca. 5 ºC s-1 to 400 ºC s-1, while warming rates spanned from ca. 2 ºC s-1 to 280 ºC s-1, for the different protocols and conditions studied. A wider measuring window (0 ºC to -150 ºC) produced lower rates for all cases. The cooling and warming rates were also related to the survival observed after the different procedures. Those protocols with the faster rates yielded the highest survival percentages.

BMO spaces related to Laguerre semigroups Harboure, Eleonor Ofelia; Chicco Ruiz, Anibal Leonardo For the system of Laguerre functions inline image we define a suitable BMO space from the atomic version of the Hardy space inline image considered by Dziubański in [7], where inline image is the maximal operator of the heat semigroup associated to that Laguerre system. We prove boundedness of inline image over a weighted version of that BMO, and we extend such result to other systems of Laguerre functions, namely inline image and inline image. To do that, we work with a more general family of weighted BMO-like spaces that includes those associated to all of the above mentioned Laguerre systems. In this setting, we prove that the local versions of the Hardy-Littlewood and the heat-diffusion maximal operators turn to be bounded over such family of spaces for inline image weights. This result plays a decisive role in proving the boundedness of Laguerre semigroup maximal operators.

Inverse expression of estrogen receptor alpha and apolipoprotein B in coronary intimal hyperplasia of surgically repaired congenital heart disease: A pre-atherosclerotic condition? Castilla Lozano, Maria del Rocio; Cao, Gabriel Fernando; Kolliker Frers, Rodolfo Alberto; Muller, Angelica del Carmen; Ambrosio, Giuseppe; Milei, Jose Congenital heart diseases (CHD) or the process of their repair leads to an increased risk for adult cardiovascular disease compared with the general population. The proliferation of intimal smooth muscle cells (SMCs), which causes intimal thickenings prior to any evidence of visible lipid deposition, was proposed to be the initial lesion of coronary atherosclerosis. The increasing trend to consider intimal thickenings as possible pre-atherosclerotic lesions is based on the distribution of intimal hyperplasia in children and the localization of characteristic atherosclerotic lesions observed in adult humans. Early coronary artery lesions may range from focal areas with mild myointimal thickenings in prenatal life to early soft plaques in infants, which may also present as intermingled lesions with components of both categories, more frequently observed with increasing age. Also,we proposed that TGF-β1 expressionmight be considered another possible predisposing factor to develop atherosclerotic coronary artery disease in CHD patients. On the other hand, estrogen receptor-α (ERα) appears to be responsible for the protective effects of estrogens against atherosclerotic vascular disease. The aim of this paper was to analyze the immunohistochemical expression of ERα, TGF-β1 and apolipoprotein B in coronary intimal hyperplasia in children with CHD and the possible increased risk for the development pre-atherosclerotic lesions.

Numerical integration of the stochastic Landau-Lifshitz-Gilbert equation in generic time-discretization schemes Romá, Federico José; Cugliandolo, Leticia F.; Lozano, Gustavo Sergio We introduce a numerical method to integrate the stochastic Landau-Lifshitz-Gilbert equation in spherical coordinates for generic discretization schemes. This method conserves the magnetization modulus and ensures the approach to equilibrium under the expected conditions. We test the algorithm on a benchmark problem: the dynamics of a uniformly magnetized ellipsoid. We investigate the influence of various parameters, and in particular, we analyze the efficiency of the numerical integration, in terms of the number of steps needed to reach a chosen long-time with a given accuracy.

Carma Large Area Star Formation Survey: observational analysis of filaments in the serpens south molecular cloud Fernandez Lopez, Manuel; Arce, H. G.; Looney, Leslie W.; Mundy, Lee G.; Storm, S.; Teuben, P. J. ; Lee, K.; Segura Cox, Dominique M.; Isella, A.; Tobin, John J.; Rosolowsky, E.; Plunkett, A. ; Kwon, Woojin; Kauffmann, J.; Ostriker, E. ; Tassis, K.; Shirley, Y. L.; Pound, M. We present the N2H+ (J = 1 → 0) map of the Serpens South molecular cloud obtained as part of the CARMA Large Area Star Formation Survey. The observations cover 250 arcmin2 and fully sample structures from 3000 AU to 3 pc with a velocity resolution of 0.16 km s−1, and they can be used to constrain the origin and evolution of molecular cloud filaments. The spatial distribution of the N2H+ emission is characterized by long filaments that resemble those observed in the dust continuum emission by Herschel. However, the gas filaments are typically narrower such that, in some cases, two or three quasi-parallel N2H+ filaments comprise a single observed dust continuum filament. The difference between the dust and gas filament widths casts doubt on Herschel ability to resolve the Serpens South filaments. Some molecular filaments show velocity gradients along their major axis, and two are characterized by a steep velocity gradient in the direction perpendicular to the filament axis. The observed velocity gradient along one of these filaments was previously postulated as evidence for mass infall toward the central cluster, but these kind of gradients can be interpreted as projection of large-scale turbulence.

Pliocene Orographic Barrier Uplift in the Southern Central Andes Pingel, Heiko; Alonso, Ricardo Narciso; Mulch, Andreas; Rohrmann, Alexander; Sudo, Masafumi; Strecker, R. Sedimentary basin fills along the windward flanks of orogenic plateaus are valuable archives of paleoenvironmental change with the potential to resolve the history of surface uplift and orographic barrier formation. The intermontane basins of the southern Central Andes contain thick successions of sedimentary material that are commonly interbedded with datable volcanic ashes. We relate variations in the hydrogen isotopic composition of hydrated volcanic glass (δDg) of Neogene to Quaternary fills in the semiarid intermontane Humahuaca Basin (Eastern Cordillera, northwest Argentina) to spatiotemporal changes in topography and associated orographic effects. δD values from volcanic glass in the basin strata (–117‰ to –98‰) show two main trends that accompany observed tectonosedimentary events in the study area. Between 6.0 and 3.5 Ma, δDg values decrease by ∼17‰; this is associated with surface uplift in the catchment area. After 3.5 Ma, δDg values show abrupt deuterium enrichment, which we associate with (1) the attainment of threshold elevations for blocking moisture transport in the basin-bounding ranges to the east, and (2) the onset of semiarid conditions in the basin. Such orographic barriers throughout the eastern flanks of the Central Andes have impeded moisture transport into the orogen interior; this has likely helped maintain aridity and internal drainage conditions on the adjacent Andean Plateau.