Action of fosetyl‐al and metalaxyl against Phytophthora austrocedri Silva, Patricia Valeria; Vélez, María Laura; Hernández Otaño, D.; Nuñez, C.; Greslebin, Alina Gabriela Fosetyl‐Al and metalaxyl, the most commonly used systemic fungicides against Phytophthora, were evaluated for their efficacy to control Phytophthora austrocedri, the pathogen that causes a serious disease at the Austrocedrus chilensis forests in Patagonia. The effect of the chemicals on pathogen development in vitro and in planta was analysed. Both chemicals were shown to protect plants from the pathogen. In vitro assays showed that asexual reproduction was sensitive to both chemicals. However, mycelial growth and sexual reproduction, which were clearly sensitive to metalaxyl, were sensitive only to high concentrations of fosetyl‐Al. Fosetyl‐Al and metalaxyl had almost the same efficacy when applied preventively by soil drench to seedlings. This difference between in vitro and in planta results can be attributed to the dual action of fosetyl‐Al, not only inhibiting the pathogen but also stimulating host defence. In adult trees, preventive and curative treatments were tested, but only the fosetyl‐Al preventive treatment was effective in the assayed conditions. Interestingly, seedlings pretreated with both fungicides were less susceptible to the effectors secreted by the pathogen. Our results indicate that fosetyl‐Al and metalaxyl provide some resistance to the plant besides the fungistatic direct action on the pathogen. Further studies to elucidate a possible resistance‐inducing activity of these chemicals and the mechanisms involved are underway.

Melatonin-Induced Oncostasis, Mechanisms and Clinical Relevance Cardinali, Daniel Pedro; Escames, Germaine; Acuña Castroviejo, Darío; Ortiz, Francisco; Fernández Gil, Beatriz; Guerra Librero, Ana; García López, Sergio; Shen, Ying; Florido, Javier Melatonin is a natural substance ubiquitously distributed and present in almost all living species, from unicellular organisms to humans. Melatonin is synthesized not only in the pineal gland but also in most tissues in the body where it may have a cytoprotective function via paracrine or autocrine effects. Melatonin is effective in suppressing neoplastic growth in a variety of tumors. The mechanisms involved include antiproliferative effects via modulation of cell cycle, ability to induce apoptosis in cancer cells, anti-angiogenic and antimetastatic effects, anti-estrogenic activity, the capacity to decrease telomerase activity, immune modulation, and direct and indirect antioxidant effects. Besides these oncostatic properties, melatonin deserves to be considered in the treatment of cancer for two other reasons. First, because its hypnotic-chronobiotic properties, melatonin use that can allow the clinician to effectively address sleep disturbances, a major co-morbidity in cancer. Second, because melatonin’s anxiolytic and antidepressant effects, it has a possible application in two other major co-morbidities seen in cancer patients, i.e. depression and anxiety. This report summarizes the possible mechanisms involved in melatonin oncostasis and reviews what is known about the clinical application of melatonin as an adjuvant therapy in cancer patients.

Thalidomide analogues: Tumor necrosis factor-alpha inhibitors and their evaluation as anti-inflammatory agents Casal, Juan José; Bollini, Mariela; Lombardo, Maria Elisa; Bruno, Ana María A series of related thalidomide derivatives (2-9) were synthesized by microwave irradiation and evaluated for anti-inflammatory activity. Such activity was assessed in vivo and ex vivo. Compounds 2, 8 and 9 showed the highest levels of inhibition of TNF-α production. On rat paw edema and hyperalgesia assays, compound 9, (1,4-phthalazinedione) demonstrated the highest in vivo anti-inflammatory activity. Thus, compound 9 can be considered as a promising compound to be subjected to further modification to obtain new agents for the treatment of inflammatory diseases.

The AIMSS Project, III : the stellar populations of compact stellar systems Janz, Joachin; Norris, Mark A.; Forbes, Duncan A.; Huxor, Avon; Romanowsky, Aaron; Frank, Matthias; Escudero, Carlos Gabriel; Faifer, Favio Raúl; Forte, Juan Carlos; Kannappan, Sheila J.; Maraston, Claudia; Brodie, Jean; Strader, Jay; Thompson, Bradley In recent years, a growing zoo of compact stellar systems (CSSs) have been found whose physical properties (mass, size, velocity dispersion) place them between classical globular clusters (GCs) and true galaxies, leading to debates about their nature. Here we present results using a so far underutilized discriminant, their stellar population properties. Based on new spectroscopy from 8-10m telescopes, we derive ages, metallicities, and [α/Fe] of 29 CSSs. These range from GCs with sizes of merely a few parsec to compact ellipticals (cEs) larger than M32. Together with a literature compilation, this provides a panoramic view of the stellar population characteristics of early-type systems. We find that the CSSs are predominantly more metal rich than typical galaxies at the same stellar mass. At high mass, the cEs depart from the mass-metallicity relation of massive early-type galaxies, which forms a continuous sequence with dwarf galaxies. At lower mass, the metallicity distribution of ultracompact dwarfs (UCDs) changes at a few times 10^7 M⊙, which roughly coincides with the mass where luminosity function arguments previously suggested the GC population ends. The highest metallicities in CSSs are paralleled only by those of dwarf galaxy nuclei and the central parts of massive early types. These findings can be interpreted as CSSs previously being more massive and undergoing tidal interactions to obtain their current mass and compact size. Such an interpretation is supported by CSSs with direct evidence for tidal stripping, and by an examination of the CSS internal escape velocities.

Hydroxylation and translational adaptation to stress: some answers lie beyond the STOP codon Katz, Maximiliano Javier; Gándara, Lautaro; de Lella Ezcurra, Ana Laura; Wappner, Pablo Regulation of protein synthesis contributes to maintenance of homeostasis and adaptation to environmental changes. mRNA translation is controlled at various levels including initiation, elongation and termination, through post-transcriptional/translational modifications of components of the protein synthesis machinery. Recently, protein and RNA hydroxylation have emerged as important enzymatic modifications of tRNAs, elongation and termination factors, as well as ribosomal proteins. These modifications enable a correct STOP codon recognition, ensuring translational fidelity. Recent studies are starting to show that STOP codon read-through is related to the ability of the cell to cope with different types of stress, such as oxidative and chemical insults, while correlations between defects in hydroxylation of protein synthesis components and STOP codon read-through are beginning to emerge. In this review we will discuss our current knowledge of protein synthesis regulation through hydroxylation of components of the translation machinery, with special focus on STOP codon recognition. We speculate on the possibility that programmed STOP codon read-through, modulated by hydroxylation of components of the protein synthesis machinery, is part of a concerted cellular response to stress.

RNA Structure Duplications and Flavivirus Host Adaptation Villordo, Sergio; Carballeda, Juan Manuel; Filomatori, Claudia Veronica; Gamarnik, Andrea Vanesa Flaviviruses include a highly diverse group of arboviruses with a global distribution and a high human disease burden. Most flaviviruses cycle between insects and vertebrate hosts; thus, they are obligated to use different cellular machinery for their replication and mount different mechanisms to evade specific antiviral responses. In addition to coding for viral proteins, the viral genome contains signals in RNA structures that govern the amplification of viral components and participate in triggering or evading antiviral responses. In this review, we focused on new information about host-specific functions of RNA structures present in the 3' untranslated region (3' UTR) of flavivirus genomes. Models and conservation patterns of RNA elements of distinct flavivirus ecological groups are revised. An intriguing feature of the 3' UTR of insect-borne flavivirus genomes is the conservation of complex RNA structure duplications. Here, we discuss new hypotheses of how these RNA elements specialize for replication in vertebrate and invertebrate hosts, and present new ideas associating the significance of RNA structure duplication, small subgenomic flavivirus RNA formation, and host adaptation.

Arbuscular mycorrhizal fungal diversity in rhizosphere spores versus roots of an endangered endemic tree from Argentina: Is fungal diversity similar among forest disturbance types? Soteras, María Florencia; Moreira, Bruno Coutinho; Grilli, Gabriel; Pastor, Nicolás; Mendes, Flávia Carneiro; Carvalho, Daniela Ruela de; Renison, Daniel; Kasuya, Maria Catarina Megumi; Souza, Francisco Adriano de; Becerra, Alejandra Gabriela The aim of this study was to compare the arbuscular mycorrhizalfungal (AMF) community of the rhizosphere and inside the roots of theperennial Polylepis australis tree. Three forest types differing in theirstructural complexity due to anthropogenic disturbances were chosen atthree different sites at the high mountains of central Argentina.Rhizosphere spores and P. australis roots of four randomly selected treeswere isolated from 36 soil samples, DNA was extracted and the 18S rDNAfragments were amplified by nested-PCR. The products were analyzed byDGGE and the bands were excised for sequencing. In total, 36 OTUs weredefined from 56 DGGE bands successfully sequenced. Forest disturbancetypes showed similar communities of AMF, as rhizosphere spores and withinthe roots of P. australis. However, DGGE clustering showed mainlydifferences between rhizosphere spores and root-colonizing AMF. Membersof Glomeraceae, Pacisporaceae, Acaulosporaceae and Gigasporaceae wereshown in rhizosphere spore samples. Root samples showed only members ofAcaulosporaceae and Gigasporaceae, which might be complementary in termsof soil resources exploration. The prevalence of the root system withtheir community of symbionts might explain the resilience of AMF soilcommunities to forests structural changes. This study presents evidenceof a possible preference in the AMF- P. australis interaction.

Contrasting effects of fire frequency on plant traits of three dominant perennial herbs from Chaco Serrano Carbone, Lucas Manuel; Aguilar, Ramiro Fire frequencies are currently increasing inmany regions across the world as a result of anthropic activities, affecting ecological processes and plant population dynamics. Fire can generate important changes in soil properties, altering nutrient dynamics and thereby plant growth. Here we analyse fire frequency effects on soil quality and plant traits of three native perennial herbaceous plants (Cologania broussonetii, Desmodium uncinatum and Rhynchosia edulis; Fabaceae) with the capacity for biologicalN2 fixation that resprouts and is abundant after fire in Chaco Serrano forests. Based on 22-year fire history, we assessed plant traits in sites with low and high fire frequencies along with unburned scenarios. We found significantly lower water content, nitrates and electrical conductivity in frequently burned soils. As a result, the three species showed consistently lower leaf area and specific leaf area in both fire frequencies, implying lower growth rates in comparison to unburned sites. However, total leaf biomass was not affected by fire, leaf phosphorus concentration was higher in R. edulis in high fire frequency and leaf N concentration was twice as large in plants growing in sites of high fire frequency in C. broussonetii and R. edulis. Such an increase in N and phosphorus concentrations is likely a result of both their conservative use of resources and their biologicalN2 fixation capacity. To our knowledge, this is the first record of such contrasting fire effects observed consistently in three co-occurring species: while plant growth decreased with fire frequency, leaf nutritional traits remain unchanged or increased in frequently burned sites. Quality-depleted and drier soils that result fromincreased fire frequenciesmay not only affect trait variation at the intraspecific level but can also drive to a homogenization of the plant community, selecting species with particular combinations of morphological and functional traits.

Dynamic transition in Landau-Zener-Stückelberg interferometry of dissipative systems: the case of the flux qubit Ferrón, Alejandro; Domínguez, Daniel; Sánchez, María José We study Landau-Zener-Stückelberg (LZS) interferometry in multilevel systems coupled to an Ohmic quantum bath. We consider the case of superconducting flux qubits driven by a dc+ac magnetic fields, but our results can apply to other similar systems. We find a dynamic transition manifested by a symmetry change in the structure of the LZS interference pattern, plotted as a function of ac amplitude and dc detuning. The dynamic transition is from an LZS pattern with nearly symmetric multiphoton resonances to antisymmetric multiphoton resonances at long times (above the relaxation time). We also show that the presence of a resonant mode in the quantum bath can impede the dynamic transition when the resonant frequency is of the order of the qubit gap. Our results are obtained by a numerical calculation of the finite time and the asymptotic stationary population of the qubit states, using the Floquet-Markov approach to solve a realistic model of the flux qubit considering up to ten energy levels.

Effect of mineral matter removal on pyrolysis of wood sawdust from an invasive species Gurevich Messina, Luciano Ignacio; Bonelli, Pablo Ricardo; Cukierman, Ana Lea Kinetics of the pyrolysis of wood sawdust from the invasive species Parkinsonia aculeata, untreated and demineralized by a mild acid treatment, is comparatively investigated in order to examine the effect of the removal of minerals naturally present in the biomass. Non-isothermal thermogravimetric analysis from room temperature up to 500°C is applied for this purpose. Demineralization shifts the process onset and the maximum degradation rate to higher temperatures, and leads to enhance the activation energy from 56 to 60 kJ mol–1, pointing to a catalytic role of alkaline and alkaline earth metals in the biomass. Likewise, the three kinds of pyrolysis products (gas, bio-char, and bio-oil) are obtained from experiments performed in a bench-scale installation at 500°C. Yields and physicochemical characteristics of the pyrolysis products are determined. The pronounced reduction in the content of metals in the sawdust leads to increase bio-oil yield in around 10%, the specific surface area of the bio-char, from ≈ 2 to ≈ 74 m2 g–1, and the higher heating value of all the pyrolysis products.

Sign Conditions for Injectivity of Generalized Polynomial Maps with Applications to Chemical Reaction Networks and Real Algebraic Geometry Müller, Stefan; Feliu, Elisenda; Regensburger, Georg; Conradi, Carsten; Shiu, Anne; Dickenstein, Alicia Marcela We give necessary and sufficient conditions in terms of sign vectors for the injectivity of families of polynomial maps with arbitrary real exponents defined on the positive orthant. Our work relates and extends existing injectivity conditions expressed in terms of Jacobian matrices and determinants. In the context of chemical reaction networks with power-law kinetics, our results can be used to preclude as well as to guarantee multiple positive steady states. In the context of real algebraic geometry, our work recognizes a prior result of Craciun, Garcia-Puente, and Sottile, together with work of two of the authors, as the first partial multivariate generalization of the classical Descartes’ rule, which bounds the number of positive real roots of a univariate real polynomial in terms of the number of sign variations of its coefficients.

Understanding trends in biological invasions by introduced mammals in southern South America: a review of research and management Ballari, Sebastián A.; Anderson, Christopher Brian; Valenzuela, Alejandro Eduardo Jorge Invasive introduced mammals (IIMs) have ecological and social dimensions that require holistic research to integrate academic disciplines with basic and applied sciences. We assessed current knowledge of IIMs to determine trends in their study and management in southern South America. A keyword search was used to select indexed papers in the Web of Science. These were reviewed to assess each study's objective, methodology, country, publication year, and taxa. Unpublished ‘grey’ literature was added to evaluate further each species’ native range, year of introduction, the reason for its introduction, its distribution, dispersal pathways, impacts, and management. Most of the 190 peer‐reviewed publications were focused on autecology and impacts of IIMs; less than 4% addressed management or social topics. Twenty‐three IIMs have been documented in the study area. The southern Magellanic subpolar forest was the most invaded ecoregion (17 spp.), and the most studied orders, from 440 records in 190 papers, were Artiodactyla (35%) and Rodentia (28%). Together, livestock and commensals brought during early European colonisation constituted 44% of this assemblage, but hunting was the major reason behind the introduction of IIMs (30%). To enhance policies and institutional frameworks pertaining to biological invasions, we highlight the importance of: 1) recognising the presence and spread of IIMs in ‘pristine’ or protected areas; 2) improving controls to prevent new introductions and escapes; 3) including social and cultural aspects of biological invasions in research and management plans; 4) reinforcing hunting regulations; 5) establishing long‐term programmes to monitor distribution and dispersion; 6) creating mechanisms for scientists and managers to co‐produce research and policy programmes oriented towards applied issues; 7) developing pilot management projects in critical areas; 8) achieving societal involvement in management programmes to ensure public acceptance; and 9) developing prioritisation tools, as resources needed to manage IIMs are often limited.

Determinantes de la equidad en el financiamiento de los medicamentos en Argentina: un estudio empírico; Determinants of equity in financing medicines in Argentina: an empirical study; Determinantes da equidade no financiamento de medicamentos na Argentina: um estudo empírico Dondo Bühler, Mariana Beatriz; Monsalvo, Mauricio; Garibaldi, Lucas Alejandro Los medicamentos constituyen un alto porcentaje del gasto en salud de los hogares, por eso, tener un sistema progresivo de financiamiento de medicamentos es fundamental para lograr un sistema de salud equitativo. Se ha propuesto que los determinantes de la equidad en el financiamiento son socioeconómicos, demográficos y asociados a la intervención pública, pero se ha avanzado poco en su evaluación empírica y en la cuantificación de su importancia relativa. En este trabajo estimamos regresiones por cuantiles a nivel provincial en Argentina y encontramos que la población mayor a 65 años, el desempleo, la existencia de laboratorio público de producción de medicamentos,las transferencias de tratamientos y la orientación del sistema desalud a la atención primaria son importantes predictores de la progresividad en el esquema de pagos. Ingresos bajos, instituciones débiles, infraestructura y provisión de servicios insuficientes redundan en respuestas sociales más regresivas a las necesidades sanitarias, empeorando las condiciones de vida y limitando las oportunidades de desarrollo.; Medicines are an important part of household health spending. A progressive system for financing drugs is thus essential for an equitable health system. Some authors have proposed that the determinants of equity in drug financing are socioeconomic, demographic, and associated with public interventions, but little progress has been made in the empirical evaluation and quantification of their relative importance. The current study estimated quantile regressions at the provincial level in Argentina and found that old age (> 65 years), unemployment, the existence of a public pharmaceutical laboratory, treatment transfers, and a health system orientated to primary care were important predictors of progressive payment schemes. Low income, weak institutions, and insufficient infrastructure and services were associated with the most regressive social responses to health needs, thereby aggravating living conditions and limiting development opportunities.; Medicamentos são uma parte importante dos gastos em saúde do agregado familiar, portanto, ter um sistema progressivo de financiamento de medicamentos é fundamental para alcançar um sistema de saúde equitativo. Foi proposto que os determinantes da equidade no financiamento são fatores socioeconômicos, demográficos e ligados à intervenção pública, mas se avançou pouco em sua avaliação empírica e na quantificação de sua importância relativa. Neste trabalho, estimamos regressões por quantis no nível provincial na Argentina e encontramos que a população maior de 65 anos, o desemprego, a existência de laboratório de produção pública de medicamentos, transferências de tratamentos e orientação do sistema de saúde para atenção primária são importantes preditores da progressividade dos sistemas de pagamento. Baixa renda, instituições fracas, infraestrutura e oferta insuficiente de serviços resultam em mais regressivas respostas sociais às necessidades de saúde, agravando as condições de vida e limitando as oportunidades de desenvolvimento.

Immature myeloid Gr-1+ CD11b+ cells from lipopolysaccharide-immunosuppressed mice acquire inhibitory activity in the bone marrow and migrate to lymph nodes to exert their suppressive function Landoni, Verónica Inés; Martire Greco, Daiana; Rodriguez Rodrigues, Nahuel Emiliano; Chiarella, Paula; Schierloh, Luis Pablo; Isturiz, Martín Amadeo; Fernández, Gabriela Cristina Secondary infections due to post-sepsis immunosuppression are a major cause of death in patients with sepsis.Repetitive inoculation of increasing doses of lipopolysaccharide (LPS) into mice mimics the immunosuppressionassociated with sepsis. Myeloid-derived suppressor cells (MDSCs, Gr-1+ CD11b+) are considered a majorcomponent of the immunosuppressive network, interfering with T-cell responses in many pathological conditions.We used LPS-immunosuppressed (IS) mice to address whether MDSCs acquired their suppressive ability in thebone marrow (BM) and whether they could migrate to lymph nodes (LNs) to exert their suppressive function. Ourresults showed that Gr-1+ CD11b+ cells of IS mice already had the potential to inhibit T-cell proliferation in the BM.Moreover, soluble factors present in the BM from IS mice were responsible for inducing this inhibitory ability incontrol BM cells. In addition, migration of Gr-1+ CD11b+ to LNs in vivo was maximal when cells obtained from theBM of IS mice were inoculated into an IS context. In this regard, we found chemoattractant activity in cell-free LNextracts (LNEs) from IS mice and an increased expression of the LN-homing chemokine receptor C?C chemokinereceptor type 7 (CCR7) in IS BM Gr-1+ CD11b+ cells. These results indicate that Gr-1+ CD11b+ cells found in BMfrom IS mice acquire their suppressive activity in the same niche where they are generated, and migrate to LNs toexert their inhibitory role. A better understanding of MDSC generation and/or regulation of factors able to inducetheir inhibitory function may provide new and more effective tools for the treatment of sepsis-associatedimmunosuppression.

Control of infection of tomato fruits by Alternaria and mycotoxin production using plant extracts Da Cruz Cabral, Lucía Mariana; Fernández Pinto, Virginia; Patriarca, Andrea Rosana Tomato fruits are susceptible to infection by Alternaria species. In addition, Alternaria species may contaminate the fruits with mycotoxins. There is thus interest in control systems to minimise pathogenicity and control toxin production. The objectives of this study were to examine the effect of plant extracts of Eucalyptus globulus and Calendula officinalis on the growth of strains of Alternaria alternata and A. arborescens, on pathogenicity of tomato fruits and mycotoxin production. The growth bioassays showed that the ethanolic and chloroformic fractions of E. globulus were the most effective in reducing growth of A. alternata (66–74 %) and A. arborescens (86–88 %), respectively at 2500 μg/g. The effects of plant extracts on mycotoxin biosynthesis were variable and strain dependent. The most effective fractions in decreasing mycotoxin accumulation were the ethanolic and chloroformic extracts of E. globulus, which reduced tenuazonic acid by 89 %, alternariol by 75–94 % and almost complete inhibition of alternariol monomethyl ether. All the tested fractions reduced percentage of infected tomato fruits when compared to the controls. The ethanolic and chloroformic fractions of E. globulus completely inhibited growth of A. alternata and A. arborescens on unwounded fruits and reduced the aggressiveness on wounded fruits of strains of both species significantly.

Actividad antifungica de anagallisina C sobre Candida albicans Soberon, Jose Rodolfo; Sgariglia, Melina Araceli; Soruco, Estela Mercedes; Pastoriza, Ana Cristina; Sampietro, Diego Alejandro; Vattuone, Marta Amelia Introducción: Candida albicans es un patógeno causal de infecciones que afectan diversos órganos del huésped, llegando a ser mortales. Fluconazol (FLU) es la droga más usada en tratamientos ambulatorios, pero su acción fungistática favorece el desarrollo de resistencias. La terapia combinatoria es una alternativa que podría minimizar estos problemas. A partir de la tintura de Anagallis arvensis L (Primulaceae) se purificó una saponina triterpénica identificada como Anagallina C (AnC), que sería el principal responsable de la actividad antifúngica descrita. Objetivos: Evaluar el efecto antifúngico ejercido por AnC sobre C. albicans, tanto individual como asociada con FLU. Materiales y métodos: Se empleó la cepa C. albicans ATCC 10231. La actividad antifúngica de AnC (50 μg) se evaluó preliminarmente por difusión en agar con discos, realizando experimentos con FLU (6 mg/L) y sin FLU. Las actividades antifúngicas de las drogas individuales y combinadas se cuantificaron por microdilución; se calcularon las concentraciones inhibitorias mínimas (CIMs) y la concentración inhibitoria fraccional (CIF). CIF se interpreta como efecto sinérgico: CIF≤0,5, indiferente: 0,5

A Review of Dielectric Strength with Distorted Lightning Impulses Diaz, Ricardo Ruben; Silva, J. N. Non-standard and distorted lightning impulse voltages are often actual dielectric stresses on high voltage insulation, either in laboratory tests or in service. The standard lightning impulse 1,2/50 s conveniently allows comparing the results obtained in different laboratories. However, it is not always possible to generate this impulse voltage in a laboratory because of the presence of distributed electrical parameters, such as inductance and capacitance, associated with big dimensions of circuits and apparatus. In large electric networks the lightning strength voltages produced by direct strokes and travelling surges present marked variations of time-to-front, time-to-tail, oscillations and superimposed overshoots, giving dielectric results quite different from conventional impulses. Much work has been done in the past in order to forecast the breakdown probability for the distorted impulses in insulations under test or, at least, the equivalence from a point of view of the disruptive discharge probability between the distorted voltage wave-shapes (or non-conventional impulses) and standard lightning impulses. The classic approach of the constant area criteria, which considers the time integral of the difference between the applied voltage and a constant voltage, has practical limits depending on the electrode configuration, voltage waveforms and voltage polarity. In the last decade a new approach was introduced for evaluating the parameters of impulse voltages with superimposed overshoot and oscillations on the crest. This approach, the test voltage factor or k-factor, has an experimental basis which facilitates calculation of the equivalent impulse voltage for distorted test voltages. The output of this method is the value of the lightning impulse parameters of an equivalent standard impulse, which should be dielectrically equivalent, i.e. have the same disruptive discharge probability. Then, with some restrictions, this method would estimate the disruptive probability with distorted impulses. Since the first proposal of a single test voltage factor, included in the latest h-v test standards (IEC 60060-1, 2010 and IEEE Std. 4, 2013), recent experiments have shown different values of k-factors in air gaps. The aim of this contribution is to highlight some relevant aspects of insulation performance with distorted lightning impulses.

The Phanerozoic four revolutions and evolution of paleosol ichnofacies Genise, Jorge Fernando; Bedatou, Emilio; Bellosi, Eduardo Sergio; Sarzetti, Laura Cristina; Sánchez, María Victoria; Krause, Javier Marcelo The analysis of a database composed of 166 cases of invertebrate and root trace fossils in paleosols allowed us to recognize four major evolutionary steps in the Phanerozoic evolution of paleosol ichnofaunas. Each step constitutes a revolution that is reflected in the appearance of a new ichnofacies. The emergence of the first vascular plants during the late Silurian–Early Devonian produced the most significant change in soil evolution, the appearance of rooted Histosols, Spodosols, Alfisols, Ultisols, and forest Oxisols through the Devonian and Carboniferous. The first revolution, then, occurred in the Early Devonian with these first paleosols that exhibit ichnoassemblages composed of rhizoliths. Paleosols bearing only rhizoliths constitute half of the cases in the Paleozoic and are recorded through the whole Phanerozoic. These cases may compose an archetypal ichnofacies termed the Rhizolith Ichnofacies. The Rhizolith Ichnofacies would be indicative of subaerial exposure and depending on needed studies on root morphology, probably would yield more precise and significative data on paleoenvironment and vegetation in the near future. Other cases of Paleozoic ichnoassemblages can be included in the Scoyenia Ichnofacies. The second revolution took place after the end-Permian mass extinction. It is characterized by the appearance of trace fossil assemblages that include or are dominated by earthworm and crayfish trace fossils. These ichnoassemblages are grouped in a new archetypal ichnofacies, the Camborygma Ichnofacies. The second revolution was followed by stasis that ended during the Cretaceous, when the third revolution occurred. By that time, the appearance and diversification of flowering plants triggered the diversification of groups of soil-inhabiting insects, such as ants, termites, bees, wasps, and certain beetles, which were capable of constructing linings and free-standing walls for their chambers and nests that consequently acquired a high potential of preservation. By the Late Cretaceous, the first recognizable insect trace fossils in paleosols appear as isolated examples, integrating the Camborygma Ichnofacies, or composing a new one: the Celliforma Ichnofacies. The fourth and most diverse revolution took place in the Middle Eocene, with the advent of grass-dominated habitats during the long-term cooling-drying period after the EECO, and the full establishment of all groups of modern insects, including the ball-making dung beetles. The spread of grasses produced the last step in soil evolution, that is, the appearance of soils with fine granular peds that derived in Mollisols. Traces of cicadas, dung beetles, bees, sphinx moths, ants, termites, cleptoparasites, and detritivores appear or diversify during this revolution composing the Coprinisphaera Ichnofacies. By the Oligocene, in closed-forest environments, the first assemblage dominated by termite trace fossils is recorded, composing the Termitichnus Ichnofacies. This last revolution is followed during the Neogene by a stasis only interrupted by the occasional appearance of new trace fossils from the same groups of insects.

Potenciales indicadores de usos y manejos de represas y canales antiguos en Santiago del Estero. Caso de estudio: dos sitios cercanos al bañado de añatuya sobre el Rio Salado Ortiz, Jorge Guillermo; Collantes, Miriam; Zapatiel, Julieta Cecilia; Burgos, Mónica Gabriela La provincia de Santiago del Estero se inscribe dentro de la zona de climas secos con escasas lluvias estivales, importantes períodos de sequías e inundaciones extraordinarias durante los veranos muy lluviosos. Posee temperaturas extremas y una elevada evapotranspiración con veranos calientes e inviernos fríos, correspondiente a un clima estepario con excedentes de radiación solar (Basualdo 1981). El territorio de la provincia está caracterizado por dos importantes sistemas fluviales que atraviesan la provincia, los ríos Salado y Dulce, ambos con rumbo noroeste-sudeste siguiendo en general la pendiente regional que caracteriza a la llanura Chaco-Pampeana (Martin 1999). Particularmente, la zona de bañados donde se inserta el área de estudio se encuentra afectada por la dinámica del rio Salado. Este río posee ciertas características que no lo hacen un buen proveedor de agua potable para consumo humano. Es por eso que actualmente y en el pasado el uso de represas y canales para la recolección de agua de lluvia para uso doméstico parece haber sido una práctica en común.

Paleopatología en un esqueleto humano del sitio Peñas Chicas 1.7. Antofagasta de la Sierra, Catamarca, Argentina González Baroni, Lucia Guadalupe El objetivo de esta presentación es dar a conocer los resultados del aná- lisis bioarqueológico de un esqueleto humano hallado en el sitio arqueológi- co Peñas Chicas 1.7 (en adelante Pch1.7) dentro de la Localidad Arqueológica de Punta de la Peña, ubicada a 10 km del pueblo de Antofagasta de la Sierra, Catamarca, Argentina. El mismo fue hallado en posición anatómica extendida con las piernas flexionadas. El tipo de entierro es primario directo y sobre el cuerpo se recuperaron vestimentas textiles (Gonzalez Baroni et al. 2015).