Structural and material mechanical quality of femoral shafts in rats exposed to simulated high altitude from infancy to adulthood Bozzini, Clarisa; Picasso, Emilio; Champin, Graciela Monica; Alippi, Rosa Maria; Bozzini, Carlos Eduardo Jose The growth of the body and bone mass and the mechanical properties of appendicular bone are impaired in immature rats exposed to different simulated high altitudes (SHA) (1850-5450 m) between the 32nd and the 74th days of postnatal life. Now, we report the effects of exposure to 4100 m on the above cited variables in female rats from infancy (age: 1 month) to adulthood (age: 8 months) to define the occurrence of catch up and to establish whether the effects of altitude are transient or permanent. The ex vivo right femur was mechanically tested in three-point bending. Body weight and length, and structural (loads at yielding and fracture, and stiffness) and architectural (diaphyseal cross-sectional area, cortical area, and cross-sectional moment of inertia) properties were measured at 2, 4, 6, and 8 months of exposure to SHA. The negative influence of hypoxia on all variables was similar at different ages or, in other words, the difference among ages was maintained at any extent of hypoxia. Hypoxia did not affect the elastic modulus, thus suggesting that the mechanical properties of the bone tissue were maintained. Catch up did not occur. The resulting osteopenic bone remained appropriate to its mechanical function during the entire exposure to SHA.

Infection levels of the cestode Hymenolepis diminuta in rat populations from Buenos Aires, Argentina Hancke, Diego; Suarez, Olga Virginia Ecological studies on zoonotic parasites are crucial for the design and implementation of effective measures to prevent parasite transmission. The aim of this study was to evaluate factors such as season, landscape unit, rat sex and rat body length, affecting the abundance of the cestode Hymenolepis diminuta, a parasite of synanthropic rats, within an urban environment. A parasitological survey was undertaken on 169 rats from landscape units such as shantytowns, parklands, industrial-residential areas and scrap-metal yards in Buenos Aires, Argentina. The overall prevalence of H. diminuta was 21.3%, although the occurrence of this species in rats was not homogeneous. The abundance of H. diminuta, using a zero-inflated negative binomial model, was correlated with rat body length. In shantytowns, abundance levels were higher than other landscape units, largely due to differences in individual environmental characteristics and rat assemblages. The populations of arthropod intermediate hosts could be subjected to seasonal fluctuations and the degree of urbanization. Shantytowns are overcrowded urban marginal settlements with most inhabitants living in precarious conditions and supporting large populations of rats, thereby increasing the risk of zoonotic infection.

Interaction of Phenylalanine with DPPC membranes by FTIR-ATR: influence of Water Populations In Restricted Environments of Lipid Membrane Interphases Rosa, Antonio Sebastián; Cutró, Andrea Carmen; Frías, María de los Ángeles; Disalvo, Edgardo Anibal The negative free energy previously reported is 8 explained by the stabilization of a PC-Phe (phosphocholine9 phenylalanine) complex in the presence of water shown by the 10 decrease in the symmetric stretching frequency of the 11 phosphate group of the lipid (PO2 −). An entropic contribution 12 due to the disruption of the water network around the phenyl 13 and in the membrane defect may be invoked. The dipole 14 potential decrease is explained by the orientation of the 15 carboxylate opposing to the CO of the lipids with oxygen 16 moiety toward the low hydrated hydrocarbon core. The 17 symmetric bending frequency of NH3 + group of Phe, decreases 18 in 5.2 cm−1 in relation to water congruent with zeta potential 19 shift to positive values. The Phe to DPPC dissociation 20 constant is Kd = 2.23 ± 0.09 mM, from which the free energy change is about −4.54 kcal/mol at 25 °C. This may be due to 21 hydrophobic contributions and two hydrogen bonds

The toarcian oceanic anoxic event (Early Jurassic) in the Neuquén Basin, Argentina: A reassessment of age and carbon isotope stratigraphy Al Suwaidi, Aisha H.; Hesselbo, Stephen P.; Damborenea, Susana Ester; Manceñido, Miguel Oscar; Jenkyns, Hugh C.; Riccardi, Alberto Carlos; Angelozzi, Gladys Noemí; Baudin, François The Toarcian oceanic anoxic event (T-OAE) is recorded by the presence of globally distributed marine organic carbon– rich black shales and a negative carbon isotope shift, with δ13Corg values as low as -33‰, interrupting an overarching positive excursion. Here we present new biostratigraphic data and high-resolution δ13Corg data from two Southern Hemisphere localities: Arroyo Serrucho in the north and Arroyo Lapa in the south of the Neuquén Basin, Argentina. Previous studies at these localities aimed to provide an accurate numerical age for the T-OAE and characterization of its carbon isotope stratigraphy. The new carbon isotope data and ammonite biostratigraphy presented here from Arroyo Serrucho show the T-OAE to be recorded lower in the section than supposed by previous authors, thus calling into question the published age of the T-OAE in this section. A newly investigated exposure at Arroyo Lapa North shows a complex carbon isotope record with at least three high-amplitude fluctuations in the hoelderi zone (equivalent to the serpentinum zone in northwestern Europe), with δ13Corg values of <-28‰, and two intervening positive isotope excursions, with δ13Corg values around -24‰. At Arroyo Lapa South, the characteristic major stepped negative carbon isotope excursion is recorded, with δ13Corg values of <-30‰ and total organic-carbon contents increasing to 11%; above this level an erosional surface of a submarine channel truncates the section. These new data are globally correlative and unambiguously illustrate the global reach of the T-OAE.

Intelectuales orgánicos y agitadores orgánicos. Siglo XII, España, Francia e Italia; Organic intellectuals and inorganic agitators : Spain, Italy and France : 12th century Astarita, Carlos Alberto Tomas Se estudian algunos de los agitadores e intelectuales que se desempeñaron en las revoluciones comunales de la Edad Media. Se realizan consideraciones metodológicas sobre las fuentes. A través de las crónicas se analizan discursos de reformadores, condiciones en las que se educaron y actuaron.; Are studied here some of the agitators and intellectuals who perfomed in communal revolutions in the Middle Ages. Methodological considerations are made about the sources. With the chronicles speeches are analized. Also conditions under which the acted and they were educated.

Detection of Nitric Oxide and Determination of Nitrite Concentrations in Arabidopsis thaliana and Azospirilum brasilense Foresi, Noelia Pamela; Correa Aragunde, Maria Natalia; Amenta, Melina Beatriz; Arruebarrena Di Palma, Andrés; Creus, Cecilia; Lamattina, Lorenzo There is now general agreement that nitric oxide (NO) is an important and almost ubiquitous signal in plants. Nevertheless, there are still many controversial observations and different opinions on the importance and functions of NO in plants. Partly, this may be due to the difficulties in detecting and even more in quantifying NO. Here, we summarize protocols for detecting NO and quantifying nitrite concentration in Arabidopisis seedlings and for the NO real time measurement in biofilms formed by the plant growth promoting rhizobacteria Azospirillum brasilense (A. brasilense). NO in oxygen-containing aqueous solution has a short half-life that is often attributed to a rapid oxidation to nitrite. Here we detail the use of the fluorescent probe DAF-FM DA and the electrochemical method for directly detecting and quantifying NO, respectively, and the Griess reagent to indirectly detect NO through its oxidized nitrite form. These protocols could be useful in a variety of cell types and different tissues of plants, and for microorganisms.

Role of glucocorticoids in cystic ovarian disease: Expression of glucocorticoid receptor in the bovine ovary Amweg, Ayelen Noelia; Rodríguez, Fernanda Mariel; Huber, Emilia; Marelli, Belkis Ester; Salvetti, Natalia Raquel; Rey, Florencia; Ortega, Hugo Hector The aim of this study was to characterize the expression of glucocorticoid receptor (GR) in the components of normal bovine ovary and in animals with cystic ovarian disease (COD). Changes in the protein and mRNA expression levels were determined in control cows and cows with COD by immunohistochemistry and real-time PCR. GR protein expression in granulosa cells was higher in cysts from animals with spontaneous COD and adrenocorticotropic hormone-induced COD than in tertiary follicles from control animals. In theca interna cells, GR expression was higher in cysts from animals with spontaneous COD than in tertiary follicles from control animals. The increase in GR expression observed in cystic follicles suggests a mechanism of action for cortisol and its receptor through the activation/inactivation of specific transcription factors. These factors could be related to the pathogenesis of COD in cattle.

Role of glucocorticoids in cystic ovarian disease: Expression of glucocorticoid receptor in the bovine ovary Amweg, Ayelen Noelia; Rodríguez, Fernanda Mariel; Huber, Emilia; Marelli, Belkis Ester; Salvetti, Natalia Raquel; Rey, Florencia; Ortega, Hugo Hector The aim of this study was to characterize the expression of glucocorticoid receptor (GR) in the components of normal bovine ovary and in animals with cystic ovarian disease (COD). Changes in the protein and mRNA expression levels were determined in control cows and cows with COD by immunohistochemistry and real-time PCR. GR protein expression in granulosa cells was higher in cysts from animals with spontaneous COD and adrenocorticotropic hormone-induced COD than in tertiary follicles from control animals. In theca interna cells, GR expression was higher in cysts from animals with spontaneous COD than in tertiary follicles from control animals. The increase in GR expression observed in cystic follicles suggests a mechanism of action for cortisol and its receptor through the activation/inactivation of specific transcription factors. These factors could be related to the pathogenesis of COD in cattle.

Los primeros misioneros jesuitas entre guaraníes y la experiencia de las "aldeias" de Brasil; The first Jesuit missionaries among the Guarani and the experience of the “aldeias” in Brazil Page, Carlos Alberto En la extensa bibliografía referida a las misiones jesuíticas de guaraníes poco se ha tenido en cuenta el accionar de los jesuitas portugueses en el periodo de la primera evangelización. Sin embargo y si de antecedentes se trata, muchos los han buscado desde la experiencia de los jerónimos en las Antillas, pasando por la acertada Verapaz de Bartolomé de las Casas, los primeros contactos de los jesuitas del Perú, la labor de los franciscanos en Asunción, entre otros. Pero obviamente fue significativo el trabajo de los primeros jesuitas que se internaron en suelo paraguayo y que fueron precisamente de la Asistencia de Portugal. De tal manera que el artículo quiere referenciar y valorizar el accionar de estos jesuitas que habían tenido su propia experiencia con las aldeias del Brasil, que la transportaron al Paraguay con sus previas y exitosas misiones itinerantes que realizaron en el Guayrá, donde incluso lograron consolidar su propio aprendizaje de la lengua y formar agrupamientos indígenas cristianos que fueron el germen de las futuras reducciones.; In the extensive literature on the Jesuit missions of the Guaranis, little account has been taken of the Portuguese Jesuits’ work during the first evangelization period. However, many have sought for antecedents of such work in the Jeronimos’ experience in the West Indies, from the well-chosen Verapaz of Bartolomé de las Casas to the first contacts of the Jesuits in Peru as well as the Franciscans’ work in Asunción, among others. Yet the work of the first Jesuits that settled in Paraguayan territory and belonged, precisely, to the Portuguese Assistance was, without any doubt, significant. Therefore the purpose of the article is to refer to and highlight the work of these Jesuits who had had their own experience with the aldeias of Brazil and took it to Paraguay along with their previous and successful missions in Guayrá, where they could even consolidate their own learning of the language and create Christian indigenous groups that were the seeds of future reductions.

Impacts of Crop Residue on Damage by Sugarcane Pests during the Tillering Phase in Argentina Isas, Marcos Gerardo; Perez, Maria Lucia del Pilar; Salvatore, Analia; Gastaminza, Gerardo; Willink, Eduardo; White, William One of the most important recent changes in sugarcane cultural practices in Tucumán, Argentina, is the adoption of the practice of green-cane harvesting, which involves harvesting the sugarcane crop in the absence of burning. The objective of this study was to assess the impact of the post-harvest crop residue (also sometimes known as "trash blanket") on Elasmopalpus lignosellus (Zeller) (Lepidoptera: Pyralidae) and Pseudaletia unipuncta Haworth (Lepidoptera: Noctuidae) population dynamics in sugarcane. The study was conducted in ratoon crops for 3 growing seasons (2011, 2012, and 2013) and at 3 locations in the state of Tucumán, Argentina. The treatments consisted of rows with the crop residue burned and the crop residue retained. Removal of the crop residue by burning, compared with retention, resulted in significantly greater crop damage by E. lignosellus in all locations and years. In contrast, damage by P. unipuncta was observed exclusively on plots where crop residue was retained. Comparing the pest status of 2 insects, E. lignosellus seems to be more consistently deleterious to sugarcane yield than P. unipuncta, and chemical control of this species is not very effective. Therefore, leaving the crop residue in place seems to be the most appropriate crop management approach, although it is important also to monitor P. unipuncta populations in order to implement control should it be necessary.

Non-congruent fossil and phylogenetic evidence on the evolution of climatic niche in the Gondwana genus Nothofagus Hinojosa, Luis Felipe; Gaxiola, Aurora; Pérez, María Fernanda; Quattrocchio, Mirta Elena; Carvajal, Francy; Campano, María Francisca; Nishida, Harufumi; Uemura, Kazuhiko; Bustamente, Ramiro; Arroyo, Mary T.K. Aim: We used fossil and phylogenetic evidence to reconstruct climatic niche evolution in Nothofagus, a Gondwana genus distributed in tropical and temperate latitudes. To assess whether the modern distribution of the genus can be explained by the tropical conservatism hypothesis, we tested three predictions: (1) species from all Nothofagus subgenera coexisted under mesothermal climates during the early Eocene, (2) tolerance to microthermal climates evolved during the Eocene-Oligocene cooling from an ancestor that grew under mesothermal conditions; and (3) the climatic niche in Nothofagus is phylogenetically conserved. Location: Australia, New Zealand, New Caledonia, Papua-New Guinea and South America. Methods: We estimated the palaeoclimate of the Early Eocene, fossil-bearing Ligorio Marquez Formation (LMF, Chile), using coexistence and leaf physiognomic analysis. We reconstructed ancestral climatic niches of Nothofagus using extant species distributions and a time-calibrated phylogeny. Finally, we used the morphological disparity index and phylogenetic generalized least squares to assess whether climatic variables follow a Brownian motion (BM) or an Ornstein-Uhlenbeck (OU) model of evolution. Results: Our palaeoclimatic estimates suggest mesothermal conditions for the LMF, where macrofossils associated with subgenera Lophozonia and possibly Fuscospora, and fossil pollen of Brassospora and Fuscospora/Nothofagus were recorded. These results are not supported by our phylogenetic analysis, which instead suggests that the ancestor of Nothofagus lived under microthermal to marginally mesothermal conditions, with tolerance to mesothermal conditions evolving only in the subgenus Brassospora. Precipitation and temperature dimensions of the realized climatic niche fit with a gradual BM or constrained OU model of evolution. Main Conclusions: Our results suggest that the use of phylogenetic reconstruction methods based only on present distributions of extant taxa to infer ancestral climatic niches is likely to lead to erroneous results when climatic requirements of ancestors differ from their extant descendants, or when much extinction has occurred.

Las emociones como metaprogramas: lo que la psicología evolucionista nos puede enseñar sobre las emociones; Emotions as meta-programms: what evolutionary pshychology can teach us about them Melamed, Andrea Florencia El debate en torno a la caracterización de las emociones permanece abierto. Las respuestas se han agrupado en dos corrientes: la cognitiva, sostiene que las emociones están constituidas (esencialmente) por algún tipo de juicio evaluativo; y la perceptiva, niega que una evaluación tal sea necesaria para que ocurra una emoción. El presente trabajo se propone evaluar la propuesta de la psicología evolucionista de cara a la problemática de las emociones. En particular, examina la posibilidad de que esta novedosa concepción de las emociones, como metaprogramas, contribuya a disolver la disputa entre los que abogan por la composición meramente perceptiva de las emociones y aquellos que, contrariamente, defienden la participación necesaria de algún tipo de juicio cognitivo, para que se dé un fenómeno emocional.; The problem of how to characterize emotions is still open. Different approaches have been grouped into two major views: on the one hand, cognitive theory holds that emotions are essentially constituted by some kind of evaluative judgment; on the other, perceptual theory denies that an evaluation of that sort is necessary for an emotion to occur. In this paper I examine the proposal of evolutionary psychology, specially in the face of emotion problems. In particular, I consider the possibility that their original conception of emotions as superordinate programs, could solve the dispute between the perceptual view and those that defend that a cognitive component, usually an appraisal, is required for an emotion to occur.

Challenges in Protein Formulation Focused on Extrusion-Spheronization Process Ravetti, Soledad; Hergert, Lisandro Yamil; Sparo, Mónica Delfina; Sanchez Bruni, Sergio Fabian; Palma, Santiago Daniel Biotechnology revolution had led the overcoming of different types of therapeutic protein because of theirchemical structure can perform specific reactions in the body, increasing efficacy and decreasing side effects.Numerous efforts were made to optimize the physicochemical properties of the proteins used for therapeuticand studied different methods for an effective administration of the protein contained in the medicine,evaluating different routes of administration to achieve the desired therapeutic effects. The delivery systemfor oral pharmaceutical proteins and peptides is still in development stage. There are number of limitationsto oral delivery of proteins such as barriers to peptide bioavailability after oral administration, intestinalmembrane permeability, size, intestinal and hepatic metabolism and solubility. Pellets have shown greatpotential in the delivery of proteins/peptidal drugs. Some strategies of development of oral protein andpeptides has always been challenged, optimizing the safety and efficacy while ensuring the ability tomanufacture the drug while maintaining quality and stability. The pelletization techniques have beenreviewed in numerous papers, is a technique that enables the formation of spherical beads or pellets with amean diameter usually ranging from 0.5-2.0 mm. Pellets are prepared by different techniques, such asextrusion and spheronization. This review discusses challenges in protein formulation that have been used toprepare pelletized dosage forms using the extrusion-spheronization process.

Centro histórico de Quito : aportes para reflexionar sobre la preservación de las casas patio desde el estado de concientización usuaria; Historical Center of Quito : an experience for the preservation of courtyard houses with an emphasis on user awareness Sanchez, Lorena Marina; Woolfson, Olga La temprana declaración de Quito como Patrimonio de la Humanidad en 1978 la convierte en un ejemplo latinoamericano con una singular experiencia preservacionista. Su Centro Histórico compone una amalgama de períodos y bienes, destacándose la presencia del sincretismo español-aborigen. Esta hibridación sobrevive en el área de amortiguación, compuesta por diferentes barrios, a través de una tipología residencial característica: las casas patio. Con un sinfín de complejidades para su tratamiento, estas viviendas componen gran parte de la identidad habitacional quiteña, aunque sólo recientemente han adquirido un nuevo protagonismo dentro del marco de protección residencial. Por ello y mediante un abordaje histórico-arquitectónico y social, se ha indagado el fragmento patrimonial del barrio San Juan, representativo de lo que acontece en el área de amortiguación. Desde una concepción de la investigación exploratoria, de carácter principalmente cualitativo y centrada en la concientización de los usuarios, se exponen los diagnósticos y lineamientos de acción asociados. Esta aproximación se ha realizado mediante la observación in situ, el análisis de planimetrías, bibliografía y fotografías, la realización de entrevistas y encuestas de opinión. De esta forma se presentan reflexiones finales junto con un desarrollo metodológico factible de ser apropiado a otros bienes residenciales en otros contextos urbanos.; The early declaration of Quito as a World Heritage site in 1978, makes this city a Latin American example with a remarkable preservationist experience. Its Historical Centre composes a blend of periods and goods, emphasizing on the presence of Spanish-Aborigine syncretism stands. This hybridation survives in the buffer area, made up of different neighborhoods, through a residential property typology: the patio houses. With endless complexities to their approach, these homes comprise the residential identity of Quito, but they have only recently taken on a new protagonism within a residential protection framework. Therefore, and through a historical-architectural and social approach, has been investigated the patrimonial fragment of the neighbourhood of San Juan, which is representative of what happens in the buffer area. Diagnosis and guidelines are exposed from a conception of exploratory study, mainly qualitative and focused on users awareness. This approximation has been carried on through the observation in situ, the analysis of planimetry, bibliography, photographs, the carrying out of interviews and opinion polls. Thus, final reflections are presented along with a methodological development feasible of being adapted to other residential properties in other urban contexts.

Notelmis Hinton y Onychelmis Hinton (Coleoptera: Elmidae: Elminae) de Colombia: claves taxonóicas ilustradas; Notelmis Hinton y Onychelmis Hinton (Coleoptera: Elmidae: Elminae) from Colombia: illustrating taxonomical keys Gonzalez Córdoba, Marcela; Zuñiga, Marıa del Carmen; Manzo, María Verónica; Giraldo, Lina Paola; Chará, Julián Material de los géneros Notelmis Hinton y Onychelmis Hinton de diferentes localidades de Colombia es analizado. Se registran por primera vez para el país dos especies de Notelmis (N. bifoveolata y N. nodipes) y una de Onychelmis (O. leleupi), conocidas para Ecuador, Panamá y Costa Rica y se amplían los rangos de distribución de estos géneros y la especie O. longicollis. Estos taxones se ubican principalmente en la región natural andina en un rango altitudinal comprendido entre 96 y 2700 msnm. Se complementa la información con claves taxonómicas ilustradas para la separación e identificación de las especies registradas en Colombia hasta el momento, mapas de distribución a nivel genérico y específico y datos ecológicos de las localidades de colecta.; Material belonging to the genus Notelmis Hinton y Onychelmis Hinton from different localities from Colombia are evaluated. Two species of Notelmis (N. bifoveolata and N. nodipes) and one of Onychelmis (O. leleupi) are recorded in this country for the first time. The species have been previously found in Ecuador, Panama and Costa Rica. The distribution ranges for the genera Notelmis, Onychelmis, and for the species O. longicollis are also expanded for Colombia. Specimens are mainly located in the Andean natural region between altitudes of 96 and 2,700 meters above sea level. The information is supplemented with illustrated taxonomic keys for identification of the species, distribution maps, and ecological data for the sampling locations.

Mitigation of pulse-width-modulation distortion using a digital predistorter based on memory polynomials Chierchie, Fernando; Cousseau, Juan Edmundo; Paolini, Eduardo Emilio; Stefan Werner This paper presents an adaptive digital predistorter (DPD) that significantly reduces the baseband distortion of digital pulse width modulation (PWM), typically used in switching (class-D) amplifiers. A generalized Hammerstein structure (also known as power filter) composed by static nonlinearities and FIR filters is used to model the baseband behavior of PWM. We show that the contribution of the higher order terms of the nonlinearity are negligible and therefore, for practical applications, only the first three or four odd powers should be retained. The convergence of the DPD is studied and the performance is demonstrated and compared with other approaches. Good results are obtained for typical signals even when using low-order FIR filters in the DPD. Measurement results obtained using a digital signal processor are also presented aiming to validate the proposed approach.

Approximate solutions to the quantum problem of two opposite charges in a constant magnetic field Ardenghi, Juan Sebastian; Gadella, M.; Negro, J. We consider two particles of equal mass and opposite charge in a plane subject to a perpendicular constant magnetic field. This system is integrable but not superintegrable. From the quantum point of view, the solution is given by two fourth degree Hill differential equations which involve the energy as well as a second constant of motion. There are two solvable approximations in relation to the value of a parameter. Starting from each of these approximations, a consistent perturbation theory can be applied to get approximate values of the energy levels and of the second constant of motion.

Influence of macrophyte integrity on zooplankton habitat preference, emphasizing the released phenolic compounds and chromophoric dissolved organic matter Gutierrez, Marìa Florencia; Mayora, Gisela Paola Macrophyte health status can influence the composition of their exudates causing different effects on zooplankton behavior and distribution in nature. We hypothesize that: (1) the release of phenolic compounds and chromophoric dissolved organic matter (CDOM) depends on macrophyte species and its health status (broken macrophytes: BM, or healthy macrophytes: HM); (2) the repellency effect depends on zooplankton species, macrophyte species and its health status; and (3) higher concentrations of phenolic compounds and CDOM produce a stronger repellency effect. Phenolic compounds and CDOM were analyzed in exudates of BM and HM of Salvinia sp., Eichhornia crassipes, Pistia stratiotes, Azolla sp. and Ludwigia peploides. Through a flow-through experiment, the repellency produced by these exudates was assessed in two copepods (Notodiaptomus conifer and Argyrodiaptomus falcifer) and one cladoceran (Ceriodaphnia dubia). Our hypotheses were partially validated. The quantity of exudated phenolic compounds and CDOM depended on macrophyte species and, to a lesser extent, on the plant health status. The repellency effect was affected by macrophyte and zooplankton species but not by the health status of plants. Only C. dubia and A. falcifer increased their evasion behavior when phenolic compound and CDOM concentrations increased. In brief, the structuring effect of repellent substances depends on different factors. Under a certain threshold concentration, zooplankton behavior might depend on the information associated with the plant odor (e.g., predation risk, structural complexity) more than on the quantity of the released chemical compounds. Above this threshold, evasion would be the only possible option to avoid damaging effects.

Tectonic models for the Patagonian orogenic curve (southernmost Andes): An appraisal based on analog experiments from the Fuegian thrust-fold belt Torres Carbonell, Pablo Juan; Guzman, Cecilia Griselda; Yagupsky, Daniel Leonardo; Dimieri, Luis Vicente Tectonic models for the evolution of the Patagonian orogenic curve were evaluated using analog experiments that considered either a rotational or a non-rotational orogenic backstop, combined with a basement promontory on the foreland cratonic margin. Five different kinematic configurations were used, aiming to evaluate the influence of the Río Chico Arc as a rigid obstacle on the evolution of the Fuegian thrust-fold belt. Rotations, strains and displacement fields obtained from each analog experiment were compared with the structural geology known from the Fuegian thrust-fold belt, in order to appraise the tectonic models that are more consistent with the natural structure. The push of a counterclockwise rotational backstop, combined with the buttressing effect of a foreland promontory, seem of major importance in controlling the final structure and map-view shape of the thrust wedge.

Oldest record of Thinocoridae (Aves, Charadriiformes) from South America; Le plus ancien thinocoridé (Aves, Charadriiformes) d’Amérique du Sud Agnolin, Federico; Tomassini, Rodrigo Leandro; Contreras, Victor Hugo Here we describe an isolated distal end of tarsometatarsus coming from the late Miocene levels of the Loma de Las Tapias Formation (San Juan Province, Argentina). The specimen was identified as a Thinocoridae, and constitutes the oldest record for the clade. It also represents the only Tertiary finding for the family from South America and one of the scarce avian remains reported from central Argentina. This record provides new information on the palaeobiogeography of the clade.; Nous décrivons ici une extrémité distale isolée de tarsométatarse provenant du Miocène terminal de la Formation Loma de Las Tapias (Province de San Juan, Argentine). Le spécimen a été identifié comme un Thinocoridae, et constitue le plus ancien enregistrement de cette famille en Amérique du Sud. Il représente aussi la seule occurrence de thinocoridé dans le Tertiaire d’Amérique du Sud et l’un des rares restes d’oiseaux rapportés du centre de l’Argentine. Cette découverte fournit des informations sur la paléobiogéographie des représentants fossiles de ce clade.