Vínculos y redes sociales en torno a colecciones de museos. Las colecciones arqueológicas del Museo Histórico del Norte (Salta), hacia mediados del siglo XX; Links and social networks regarding museum collections. The archaeological collections of the Museo Histórico del Norte (Salta), towards the mid-20th century Castellanos, María Cecilia; Mamani, Elsa Mabel; Rueda, Facundo; Rodríguez, Mónica; Lavilla, Florencia El artículo aborda la conformación de la colección arqueológica del Museo Histórico del Norte (Provincia de Salta), para lo cual se reseña el contexto social y político, nacional y local, bajo el cual se crea el Museo y se hace referencia a las formas de adquisición de la colección durante los momentos iniciales de la institución. Los trabajos realizados sobre la colección arqueológica aportaron información que permitió indagar en problemáticas relacionadas con las redes sociales que se establecieron entre el Museo, benefactores o donantes de piezas arqueológicas y otras instituciones durante la primera mitad del siglo XX. El cruce de diferentes fuentes generó también ideas para pensar los procesos de institucionalización de la práctica arqueológica en la provincia y el papel que pudieron haber tenido las colecciones arqueológicas; This work analyzes the conformation of the archaeological collection of the “Museo Histórico del Norte” (Salta province). For this goal, the creation of the museum is reviewed in terms of the social and political context of the time at both local and national scales. The manner of acquisition of the collections during the initial moments of the institution is also referenced. The studies carried out on this archaeological collection provided information that allowed us to preliminary define the social networks that were established between the museum, benefactors or donors of archaeological items and other institutions during the first half of the 20th century. Cross-referencing different documentary sources also generated ideas to analyze the processes of institutionalization of archaeological practice in Salta and the role that could have been played by archaeological collections

Drivers of global Scolytinae invasion patterns Lantschner, María Victoria; Corley, Juan Carlos; Liebhold, Andrew M. Biological invasions are affected by characteristics of invading species, strength of pathway connectivity among world regions and habitat characteristics of invaded regions. These factors may interact in complex ways to drive geographical variation in numbers of invasions among world regions. Understanding the role of these drivers provides information that is crucial to the development of effective biosecurity policies. Here we assemble for the first time a global database of historical invasions of Scolytinae species and explore factors explaining geographical variation in numbers of species invading different regions. This insect group includes several pest species with massive economic and ecological impacts and these beetles are known to be accidentally moved with wood packaging in global trade. Candidate explanatory characteristics included in this analysis are cumulative trade among world regions, size of source species pools, forest area, and climatic similarity of the invaded region with source regions. Species capable of sib‐mating comprised the highest proportion on nonnative Scolytines, and these species colonized a higher number of regions than outbreeders. The size of source species pools offered little power in explaining variation in numbers of invasions among world regions nor did climate or forest area. In contrast, cumulative trade had a strong and consistent positive relationship with numbers of Scolytinae species moving from one region to another, and this effect was highest for bark beetles, followed by ambrosia beetles, and was low for seed and twig feeders. We conclude that global variation in Scolytine invasions is primarily driven by variation in trade levels among world regions. Results stress the importance of global trade as the primary driver of historical Scolytinae invasions and we anticipate other hitchhiking species would exhibit similar patterns. One implication of these results is that invasions between certain world regions may be historically low because of past low levels of trade but future economic shifts could result in large numbers of new invasions as a result of increased trade among previously isolated portions of the world. With changing global flow of goods among world regions, it is crucial that biosecurity efforts keep pace to minimize future invasions and their impacts.

Trabajo, género y desigualdades en la economía popular. Una mirada sobre la situación de los vendedores/as callejeros en tiempos de pandemia; Work, gender and inequalities in the popular economy. A look at the situation of street vendors in times of pandemic; Trabalho, género e desigualdades na economia popular. Umolhar sobre a situação dos vendedores ambulantes em tempos de pandemia Hopp, Malena Victoria; Maldovan Bonelli, Johanna; Frega, Mariana Gabriela; Trajtember, Agustina Las medidas de Aislamiento Social, Preventivo y Obligatorio, decretadas el 20 de marzo del 2020 en la Argentina a causa del avance de la pandemia del COVID-19, han puesto en evidencia las profundas desigualdades en el mundo del trabajo y en las condiciones de vida de los distintos sectores de la sociedad. En este contexto, los trabajadores y las trabajadoras de la economía popular han sido fuertemente afectados: la inmensa mayoría viven al día con ingresos de subsistencia y se encuentran por fuera de los dispositivos formales de protección social.En este artículo nos proponemos abordar la particular situación en la que se encuentran los/as vendedores/as callejeros/as de la Ciudad Autónoma de Buenos Aires, considerando dos dimensiones que permiten comprender las condiciones de (re)producción y profundización de las desigualdades en tiempos de crisis: el género y el acceso a las políticas públicas. El análisis muestra que, frente al escenario actual y futuro, se requiere un cambio en la orientación de las acciones estatales que gire desde la lógica asistencial hacia el reconocimiento del valor económico, social y cultural del trabajo que aportan los/as trabajadores/as de la economía popular y contemplando sus problemáticas de manera integral con perspectiva de género.

In Silico Analysis of Sea Urchin Pigments as Potential Therapeutic Agents Against SARS-CoV-2: Main Protease (Mpro) as a Target Rubilar Panasiuk, Cynthia Tamara; Barbieri, Elena Susana; Gázquez, Ayelén; Avaro, Marisa; Vera Piombo, Mercedes; Gittardi Calderón, Agustín Adolfo; Seiler, Erina Noé; Fernandez, Jimena Pía; Sepúlveda, Lucas Roberto; Chaar, Florencia The SARS-CoV-2 outbreak has spread rapidly and globally generating a new coronavirus disease (COVID-19) since December 2019 that turned into a pandemic. Effective drugs are urgently needed and drug repurposing strategies offer a promising alternative to dramatically shorten the process of traditional de novo development. Based on their antiviral uses, the potential affinity of sea urchin pigments to bind main protease (Mpro) of SARS-CoV-2 was evaluated in silico. Docking analysis was used to test the potential of these sea urchin pigments as therapeutic and antiviral agents. All pigment compounds presented high molecular affinity to Mpro protein. However, the 1,4-naphtoquinones polihydroxilate (Spinochrome A and Echinochrome A) showed high affinity to bind around the Mpro´s pocket target by interfering with proper folding of the protein mainly through an H-bond with Glu166 residue. This interaction represents a potential blockage of this protease´s activity. All these results provide novel information regarding the uses of sea urchin pigments as antiviral drugs and suggest the need for further in vitro and in vivo analysis to expand all therapeutic uses against SARS-CoV-2.

Durable performance of recycled aggregate concrete in aggressive environments Zega, Claudio Javier; Santillan, Lautaro Rodolfo; Sosa, Maria Eva; Villagrán Zaccardi, Yury Andrés Recycled aggregate concrete is an eco-friendly material that is increasingly being used in new constructions. Nowadays, this application is mainly limited by user?s lack of confidence, as coarse recycled aggregate (CRA) is usually more porous, i.e., it has a higher water absorption, than coarse natural aggregate. This difference is a primary concern for practitioners when they have to comply with durability requirements. Although some uncertainties remain in this regard, significant progress has been made in the last few years concerning the assessment of durable recycled aggregate concrete. This paper reviews this topic and includes aspects related to chloride penetration, sulfate attack, freezing and thawing, high temperature, and alkali-silica reaction. Generally, although there are some particularities related to each type of attack, the high porosity of CRA is compensated by other features, such as different texture, increased mechanical compatibility with the matrix, or content of hydration products. Experimental results in the literature show that there are no reasons to consider that durable, sustainable structures cannot be built with recycled aggregate concrete.

Manuel Costa-Iscar y el anarquismo individualista en Buenos Aires; Manuel Costa-Iscar and individualist anarchism in Buenos Aires Stavisky, Sebastián El artículo analiza el modo de practicar y difundir el anarquismo individualista por parte de Manuel Costa-Iscar, militante español que arriba a Buenos Aires en los primeros años de la década del 20. El trabajo tiene un doble propósito: avanzar en la lectura y análisis del corpus textual del autor asumiendo como perspectiva los aportes de Foucault acerca de las tecnologías del yo; discutir con ciertos modos cristalizados por la historiografía en la consideración del anarquismo individualista en Argentina.; The article analyzes the way of practicing and spreading the individualist anarchism by Manuel Costa-Iscar, a Spanish activist who arrive to Buenos Aires in the early years of the 1920s. The work has a double purpose: to advance in the reading and analysis of the textual corpus of the author, assuming as perspective the Foucault’s contributions about the technologies of the self; to discuss with certain crystallized ways in which the historiography considers individualist anarchism in Argentina.

Catálogo de la colección de cultivos de especies de hongos patógenos y simbiontes de insectos y otros artrópodos de la Argentina; Catalogue of the culture collection of symbionts and pathogenic fungal species of insects and other arthropods from Argentina Lopez Lastra, Claudia Cristina; Manfrino, Romina Guadalupe; Rodríguez, Mónica B.; Gutierrez, Alejandra Concepción; Ordoqui, Eliana; Navone, Graciela Teresa El presente trabajo, tiene como objetivo dar a conocer los datos actualizados e información relevante de las cepas de especies fúngicas entomopatógenas preservadas en la colección de cultivos del CEPAVE (Centro de Estudios Parasitológicos y de Vectores) CONICET-UNLP, Argentina. Los datos que se informan en este trabajo son de aislamientos nativos de diferentes regiones fitogeográficas de la Argentina. Para cada cepa se especifica: acrónimo, sustrato, especie de insecto hospedante, fecha de recolección, referencias de coordenadas geográficas y medio de cultivo en el que fue aislado. Los fines de esta Colección son de investigación, docencia y vinculación tecnológica a empresas. Su inicio fue en 1988 y, actualmente se encuentra registrada en la FELACC (Federación Latinoamericana de Colecciones de Cultivos) como Socio Institucional: Nº SI-06 y en la Federación Mundial de Colecciones de Cultivos (World Federation for Culture Collections – WFCC) (http://www.wfcc.info/). Siguiendo las pautas de organización de la WFCC esta colección está incorporada a: World Data Centre for Microorganisms (WDCM, Nº 973 CEP). Los métodos de preservación que se utilizan son: agua destilada estéril, papel, aceite mineral, sílica gel, freezer -20 °C y -70 °C y liofilización, siendo realizados rigurosos controles de calidad y de viabilidad de las cepas. Las cepas son caracterizadas por técnicas morfológicas y el 30 % de los aislamientos fúngicos han sido caracterizados, además, mediante técnicas de biología molecular. En la actualidad, la colección mantiene más de 650 cepas correspondientes en su mayoría a los géneros Beauveria, Metarhizium, Isaria, Lecanicillium y algunas especies de Entomophthorales.; and technological associations with companies. It started in 1988, and it is registered in the Latin American Federation of Culture Collections (FELACC) as Institutional Partner: No. SI-06, and in the World Federation for Culture Collections (WFCC) (http://www.wfcc.info/). In accordance with the WFCC guidelines, this collection is incorporated as a partner to the World Data Centre for Microorganisms (WDCM, 973 CEP). The preservation methods used are sterile distilled water, paper, mineral oil, silica gel, freezer at -20 and -70 °C and lyophilization, quality and viability controls are carried out. So far, 40 % of the species have been identified by molecular techniques, and the study of the remaining isolated species is under development. The collection consists of more than 684 strains which belong mostly to the Beauveria, Metarhizium, Isaria, Lecanicillium genera, as well as some species of Entomophthorales.

Neuroanatomy of the lumbosacral plexus in a highly diversified clade of South-American lizards. Evolution and phylogenetic implications Quipildor, Angel Matías; Quinteros, Andres Sebastian; Lobo Gaviola, Fernando Jose Only few published studies that describe the neuroanatomy of lizards. Here, we describe the neuroanatomy of several Iguanian species belonging to three families (species of Liolaemus and Phymaturus belonging to Liolaemidae, Tropidurus and Stenocercus as representatives of Tropiduridae, and Diplolaemus as a representative of Leiosauridae). Based on Sudan Black B staining and conventional dissections, the neuroanatomy of the lumbosacral region is described. Among the most outstanding results is the existence of a neuronal pattern of the lumbosacral plexus characteristic of Liolaemidae. In addition, it was found that in the genus Liolaemus the lumbosacral plexus is composed of five pairs of spinal nerves while in Phymaturus, Tropidurus, Stenocercus and Diplolaemus is composed from five to six pairs of spinal nerves (from pre-sacral, sacral, and caudal vertebrae). We find differences in the origin of the spinal nerves that constitute the plexus. In some cases, the pattern of nerves involved includes even the caudal vertebrae. Variation among taxa related to the zeugopodial innervation is described, and the homology of these nervous branches is discussed. Sexual differences were found in some species studied. Based on our results and available literature, we found three different patterns of innervation of the zeugopodium. The major contribution of this study is to provide a detailed description of lumbosacral plexus nerves pathways from their origins at the vertebral column to the muscles that they innervate.

A structural indicator for water built upon potential energy considerations Montes de Oca, Joan Manuel; Sciortino, Francesco; Appignanesi, Gustavo Adrian We introduce a parameter-free structural indicator to classify local environments of water molecules in stable and supercooled liquid states, which reveals a clear two-peak distribution of local properties. The majority of molecules are tetrahedrally coordinated (T molecules), via low-energy hydrogen bonds. The minority component, whose relative concentration decreases with a decrease in the temperature at constant pressure, is characterized by prevalently three-coordinated molecules, giving rise to a distorted local network around them (D molecules). The inter-conversion between T and D molecules explains the increasing specific heat at constant pressure on cooling. The local structure around a T molecule resembles the one found experimentally in low-density amorphous ice (a network structure mostly composed by T molecules), while the local structure around a D molecule is reminiscent of the structural properties of high-density amorphous ice (a network structure composed by a mixture of T and D molecules).

El diario de Gabriel Quiroga: reflexiones de Manuel Gálvez ante el centenario de la Revolución de Mayo; The Diary of Gabriel Quiroga: Reflections by Manuel Galvez to the centenary of the May Revolution Rubio García, Gonzalo El diario de Gabriel Quiroga fue una obra escrita a principios del siglo XX por Manuel Gálvez que, como veremos, logró calar hondo en el pensamiento de la población argentina. A su vez, es un texto que ha sido destacado por muchos intelectuales debido a sus apelaciones al nacionalismo cultural y las nociones de corte positivista, así como también sus aportes modernistas y anti positivistas. Por dicha razón, ante la diversidad de construcciones encontradas, nuestro objetivo en este trabajo es indagar y revisar las ideas que el autor sostuvo en esta obra, teniendo en cuenta que se trata de su primer acercamiento literario hacia la crítica del pasado argentino y el género de diario ficcional. Consideramos que la estrategia elegida permitió al autor destacar un personaje, representativo de otros hombres en su época, que era habilitado por la matriz realista de la obra. Bajo ese formato, logró que las posturas expuestas sirvieran como una construcción fidedigna de muchas de las ideas que circulaban en la época del Centenario y como antecedente intelectual para otros pensadores que posteriormente adhirieron al nacionalismo.; The Diario de Gabriel Quiroga was written at the beginning of the 20th century by Manuel Gálvez that, as we will see, managed to penetrate deep into the ideas of the Argentine population. In turn, it is a text that has been highlighted by many intellectuals due to its appeals to cultural nationalism and positivist topics, as well as its modernist and anti-positivist contributions. For this reason, given the diversity of constructions found, our objective in this work is to investigate and review the ideas that the author sustained in this work, bearing in mind that this is his first literary approach to criticism of the Argentine past and the genre of fictional diary chosen for the writing. We consider that the chosen strategy allowed the author to highlight a character, representative of other men in his time, who was enabled by the realistic matrix of the work. Under this format, he achieved that the positions exposed in his writing served as a reliable construction of many of the ideas that circulated in the Centennial era and as an intellectual antecedent for other intellectuals who later adhered to nationalism.

The foehn wind east of the Andes in a 20-year climate simulation Antico, Pablo Luis; Chou, Sin Chan; Brunini, Claudio Antonio This study investigates the spatial structure and the seasonal occurrence of foehn wind to the east of the Andes using a flow blocking analysis in a 20-year climate simulation. The latter was performed by the Eta-CPTEC regional model at 50-km horizontal resolution. This version of the model includes a cut-cell scheme to represent topography and a finite-volume vertical advection scheme for dynamic variables. The results indicate that foehn wind more frequently blows during winter and spring on the eastern slopes of the Andes, except to the south of 37° S where it blows at all seasons. Higher mountains of the Central Andes (27° S–35° S) and the High Plateau (15° S–27° S) result in blocked foehn events, with a weak adjustment to the geostrophic balance. On the Central Andes, rain and snow on mountain tops may also contribute to generate foehn wind on the eastern slopes. The results show that a low pressure develops to the east of the Central Andes, and also to the east of the High Plateau when foehn blows. Lower mountains in Patagonia (to the south of 37° S) result in more frequent non-blocked foehn event, with better adjustment to the geostrophic balance.

El caso de ACINDAR en Villa Constitución y el ciclo de transformaciones represivas, productivas y laborales entre dictadura y democracia; O caso da ACINDAR Villa Constitución e o ciclo de transformações repressivas, produtivas e trabalhistas entre ditadura e democracia; The case of ACINDAR Villa Constitución and the cycle of repressive, productive and labor transformations between dictatorship and democracy Basualdo, Victoria Este artículo analiza la evolución de la empresa siderúrgica Acindar Villa Constitución (Provincia de Santa Fe), en el marco de las transformaciones en la industria siderúrgica desde la década del 70 hasta la década del 90. Se detiene en los impactos de la última dictadura en Argentina (1976-1983), las conexiones entre las fuerzas armadas y la dirigencia empresarial, y el proceso represivo de inédita intensidad llevado adelante en esta etapa, así como las transformaciones en las relaciones laborales y las dimensiones productivas, y la conformación de un oligopolio siderúrgico al final de la dictadura. Analiza también el proceso de reconversión productiva entre fines de la década del 80 e inicios del 90, enfatizando que en la salida de ese ciclo de conflicto se promovió la expansión de la tercerización laboral como una estrategia con fuerte impacto en el colectivo laboral y la trayectoria productiva y empresarial.; Este artigo analisa a evolução da empresa siderúrgica Acindar Villa Constitución (província de Santa Fe), no âmbito das transformações na indústria siderúrgica desde a década de 70 até a de 90. Detém-se nos impactos da última ditadura na Argentina (1976-1983), as conexões entre as forças armadas e a liderança empresarial e o processo repressivo de inédita intensidade levado adiante nesta fase, assim como as transformações nas relações de trabalho e nas dimensões produtivas, além da conformação de um oligopólio siderúrgico no final da ditadura. Analisa também o processo de reconversão produtiva entre o final da década de 80 e o início da década de 90, enfatizando que na saída desse ciclo de conflito promoveu-se a expansão da terceirização laboral como uma estratégia com forte impacto sobre o coletivo de trabalhadores e na trajetória produtiva e empresarial.; This article analyzes the evolution of the Acindar steel mill in Villa Constitución, Province of Santa Fe, in the context the transformations of the steel industry in Argentina from the 1970s to the 1990s. It focuses on the impact of the last dictatorship (1976-1983), the connections between the armed forces and the business leadership and the repressive process of unprecedented intensity during this period. It also studies the transformations in labor relations and productive dimensions, which led to an oligopoly in steel industry by the end of the dictatorship. It also pays special attention to the process of industrial reorganization developed from the late 1980s to the early 1990s, emphasizing that in the closure of this labor conflict there was an expansion of outsourcing and subcontracting, which had a strong impact on labor relations and productive and business strategies.

Intracellular motor driven transport of rodlike smooth organelles along microtubules Fernández Casafuz, Agustina Belén; de Rossi, María Cecilia; Bruno, Luciana Molecular motors are fascinating proteins that use the energy of ATP hydrolysis to drive vesicles and organelles along cytoskeleton filaments toward their final destination within the cell. Several copies of these proteins bind to the cargo and take turns transporting the cargo attaching to and detaching from the track stochastically. Despite the relevance of molecular motors to cell physiology, key aspects of their collective functioning are still unknown. In this work we propose a one-dimensional model for the transport of extensive and smooth organelles driven by molecular motors. We ran numerical simulations to study the behavior of the cargo for different motor configurations, focusing on the transport properties observable in the experiments, e.g., average speed of the organelle and variations in length. We found that active motors drive the cargo using two different mechanisms: Either they locate in front of the cargo and pull the organelle or they situate at the cargo lagging edge and push. Variations in the organelle length is in close relation with the fraction of motors in each configuration, which depends on the resisting load. The results of this model were contrasted with experimental data obtained from the tracking of rodlike mitochondria during active transport in Xenopus laevis melanophores.

El edificio Casa Natal de Domingo Faustino Sarmiento: Un caso de arquitectura doméstica colonial en San Juan, Argentina; Domingo Faustino Sarmiento’s birth house: A case of domestic architecture in colonial San Juan, Argentina Igareta, Ana Teresa; Erostarbe Suarez, María Emilia; Chechi, Florencia Es poco lo que se ha investigado en la arqueología argentina sobre los materiales y técnicas empleadas en las provincias del oeste del país durante el periodo colonial. En el caso de la ciudad de San Juan, que durante más de dos siglos formó parte de la Gobernación de Chile, son contados los antecedentes de análisis directo de edificios o restos de edificios construidos en dicho periodo. Es por ello que se estimó de interés el estudio del edificio del Museo y Biblioteca Casa Natal de Sarmiento desde una perspectiva arqueológica, dado que se trata de uno de los pocos edificios coloniales tardíos que aún permanecen en pie en la ciudad. El presente artículo da cuenta de los resultados preliminares obtenidos durante una revisión de fuentes documentales destinada a identificar menciones relativas a las materias primas, técnicas y sistemas utilizados en la construcción de la casa y en las sucesivas reformas de las que fue objeto. La información recuperada fue utilizada para generar una primera aproximación hipotética a la materialidad de la vivienda en tres periodos claves de su historia.; Little has been written in Argentinian archeology architecture materials and techniques used at western provinces of the country during the colonial period. In the case of the city of San Juan, part of Chilean Governorate for over two centuries, there are no history of direct analysis of buildings or remains of colonial buildings. The current Museo y Biblioteca Casa Natal de Sarmiento is one of the few late colonial buildings still remain standing in the city and its analysis from an archaeological perspective was considered a valuable opportunity. This article presents the preliminary results obtained during the construction of a database that gathers all the mentions identified in documentary, historical and bibliographic sources, regarding raw materials, techniques and systems used in the construction of the house and further interventions.

Estudio de la población de carpincho (Hydrochoerus hydrochaeris) en el área natural protegida ''El Morejón'', Campana (Buenos Aires); Study of the population of capybara (Hydrochoerus hydrochaeris) in the protected area ''El Morejón'', Campana (Buenos Aires) Noya Abad, Tatiana; Calcagno, Javier Ángel; Bauni, Valeria En la Argentina, la Ecorregión Pampeana presenta bajo nivel de protección debido a su alto valor económico y al dominio privado. El reemplazo de sus ambientes naturales por usos productivos causó la retracción numérica de especies como el carpincho (Hydrochoerus hydrochaeris), que habita sus humedales. Los aspectos biológicos y ecológicos de esta especie permanecen poco estudiados en la provincia de Buenos Aires. En consecuencia, los objetivos de este estudio fueron estimar las abundancias real y relativa, la densidad y el tamaño poblacional, y determinar la estructura de la población, el patrón de actividad de los individuos en las dos lagunas presentes en el área natural protegida “El Morejón”, partido de Campana, Buenos Aires. Para ello, a lo largo del año 2014 se realizaron relevamientos de transectas de rastros y trampas cámara en las cuatro estaciones. A pesar de estar inmersa en un área urbanizada e industrializada, se obtuvo un tamaño poblacional mayor al esperado. Se estimó la presencia de un promedio de 15 individuos en la Laguna 1 y 154 en la 2, en áreas de uso estimadas de 3 y 10 ha, respectivamente. Durante el invierno se registró el mayor número de individuos, y en otoño, primavera y verano, los menores. Es posible que esto se asocie a la movilidad de los individuos en busca de alimento. Estos resultados son relevantes para una planificación correcta de medidas de manejo, y confirman la importancia de que existan reservas privadas que conserven el ecosistema natural de la región.; In Argentina, the Pampa ecoregion has a low level of protection due to its high economic value and private domain. The replacement of its natural environments by productive uses has caused the numerical retraction of species such as the capybara (Hydrochoerus hydrochaeris), which inhabits its wetlands. The biological and ecological aspects of this species have been scarcely studied in the province of Buenos Aires. Therefore, the objectives of this study were to estimate the relative, real abundance, density, population size; and determine the structure of the population, the pattern of activity of the individuals in the two lagoons present in the protected natural area “El Morejón”, Campana, Buenos Aires. For this purpose, transects of traces and camera traps were made in the four seasons, throughout 2014. Despite being immersed in an urbanized and industrialized area, a larger population size than expected was obtained. An average of 15 individuals in Laguna 1 and 154 in 2 was estimated, in estimated areas of use of 3 and 10 ha, respectively. The largest number of individuals was observed during winter, while fall, spring and summer showed the smallest. The differences may be associated with the alimentary activity. These results are relevant for a correct planning of management measures, and confirm the importance of the existence of private reserves that conserve the natural ecosystem of the region.

Quiénes son los visitantes de los museos de arte: Particularidades de los públicos del fin de semana en el Museo de Arte de Tigre (Argentina); Who are the visitors of the art museums: Particularities of the publics of the weekends at the Art Museum of Tigre (Argentina) Panozzo Zenere, Alejandra Gabriela Saber quiénes son sus visitantes es una de las principales tareas de los museos en la actualidad, en la medida en que fluctúan entre ajustarse a las imposiciones del sistema capitalista y convertirse en instituciones democráticas y participativas. No obstante, este aspecto resulta aun más dificultoso en los museos de arte, en virtud de los atributos particulares de su estructura y actores. El presente trabajo tiene como objetivo aproximar algunos criterios que permitan conocer quiénes son los visitantes de los museos de arte creados en Argentina desde el inicio del nuevo milenio. Dada la magnitud del desafío, se procura, con el foco puesto en un caso particular, trazar algunos lineamientos sostenidos en los enfoques teórico-críticos aplicados a la museología y en los estudios de públicos. En cuanto a lo metodológico, se recurrió a un estudio de visitantes que apeló a orientaciones cuantitativas y cualitativas, realizado en el Museo de Arte de Tigre durante 2017, centrado en los públicos del fin de semana. Se considera que, al indagar los rasgos singulares de esta entidad patrimonial, pueden identificarse algunos indicios que permitan comenzar a trazar un perfil, tanto general como específico, de los visitantes de los museos de arte.; Knowing who its visitors are is one of the main tasks of museums today, as they fluctuate between conforming to the impositions of the capitalist system and becoming democratic and participatory institutions. However, this aspect is even more difficult in the arts museums because of the particular attributes of their structure and its diverse actors. The present work has as main object to bring near some criteria that may allow to know who are the visitors of the art museums in Argentina since the beginning of the new millennium. Given the extent of the challenge, we’ll try, focusing in a particular case, draw some guidelines sustained in the theorical-critical approaches applied to museology and studies of the publics. In terms of methodology, a visitor study was carried out at the Tigre Art Museum in 2017, using both quantitative and qualitative guidelines, focusing on weekend audiences. It is considered that, when we question the singularities of this entity, there are some indications that a general and specific profile of visitors to art museums can begin to be identified.; Saber quem são seus visitantes é uma das principais tarefas dos museus na atualidade, na medida em que flutuam entre amoldar-se às imposições do sistema capitalista e converter-se em instituições democráticas e participativas. Não obstante, este aspecto resulta ainda mais dificultoso nos museus de arte, devido aos atributos particulares de sua estrutura e atores. O presente trabalho tem por objetivo aproximar alguns critérios que permitam conhecer quem são os visitantes dos museus de arte criados na Argentina desde o início do novo milênio. Dada a magnitude do desafio, e com o foco posto em um caso particular, buscou-se traçar alguns lineamentos sustentados nos enfoques teórico-críticos aplicados à museologia e nos estudos de públicos. Quanto à metodologia, a pesquisa teve como base um estudo de visitantes que apelou a orientações quantitativas e qualitativas, realizado no Museu de Arte de Tigre durante o ano de 2017, focado nos públicos de fim de semana. Considera-se que, ao indagarmos os traços singulares desta entidade, podem ser identificados alguns indícios que permitam começar a esboçar um perfil, tanto geral quanto específico, dos visitantes dos museus de arte.

High yield to 1-propanol from crude glycerol using two reaction steps with Ni catalysts Gatti, Martin Nicolas; Cerioni, Julieta Lucia; Pompeo, Francisco; Santori, Gerardo Fabian; Nichio, Nora Nancy The objective of the present work is to achieve high yield to 1-propanol (1-POH) by crude glycerol hydrogenolysis in liquid phase and find an alternative to the use of noble metals by employing Ni catalysts. Two Ni catalysts with different supports, alumina (γ-Al2 O3), and a phosphorous-impregnated carbon composite (CS-P) were studied and characterized in order to determine their acid properties and metallic phases. With the Ni/γ-Al2 O3 catalyst, which presented small particles of metallic Ni interacting with the acid sites of the support, it was possible to obtain a complete conversion of crude glycerol with high selectivity towards 1,2-propylene glycol (1,2 PG) (87%) at 220◦ C whereas with the Ni/CS-P catalyst, the presence of AlPOx species and the Ni2 P metallic phase supplied acidity to the catalyst, which promoted the C-O bond cleavage reaction of the secondary carbon of 1,2 PG to obtain 1-POH with very high selectivity (71%) at 260◦ C. It was found that the employment of two consecutive reaction stages (first with Ni/ γ-Al2 O3 at 220◦ C and then with Ni/CS-P at 260◦ C) allows reaching levels of selectivity and a yield to 1-POH (79%) comparable to noble metal-based catalysts.

Diseño y validación de una escala de actitudes hacia las matemáticas en estudiantes de escolaridad primaria y secundaria; Design and Validation of an Attitudes towards Mathematics Scale Stelzer, Florencia; Vernucci, Santiago; Aydmune, Yésica; del Valle, Macarena; Andrés, María Laura La actitud hacia las matemáticas refiere a la tendencia o predisposición para responder ante estímulos relacionados con la matemática. El objetivo de este estudio es evaluar las propiedades psicométricas de una Escala de Actitudes hacia las Matemáticas (EAM) para estudiantes que finalizan la escolaridad primaria e inician la secundaria. Para ello se diseñó una escala y luego se evaluaron sus propiedades psicométricas y su capacidad predictiva. Participaron 193 estudiantes de sexto grado de primaria, y primer y segundo año de secundaria (edad: ME = 12.7 años; DE = 0.36). Las correlaciones ítems-total y el Alpha de Cronbach (α = .92) indicaron que la escala es consistente. El análisis factorial exploratorio indicó una estructura de tres factores, designados competencia percibida, gusto/motivación por las matemáticas y conductas de compromiso escolar, con 55.5% de varianza explicada. Se observaron correlaciones moderadas entre las tres dimensiones de la EAM y medidas de éxito y productividad académica en matemáticas. Estos resultados sugieren que la EAM representa un medio confiable y válido para la estimación de las actitudes hacia las matemáticas.; The aim of this study is to evaluate the psychometric properties of an Attitudes towards Mathematics Scale (AMS) for students who are finishing elementary school and starting high school. For this purpose, a specific measure was designed, and its psychometric properties and predictive capacity were evaluated. 193 students of elementary (sixth grade) and high school (first and second year) participated in the study (M age = 12.7 years, SD = 0.36). Item-total correlations and Cronbach's alpha (α = .92) indicated that the scale is consistent for construct measurement. Exploratory factor analysis showed a three-factor structure, named perceived competence, liking/motivation for mathematics, and school engagement behaviours. Regarding predictive validity, moderate correlations were found among scale’s dimensions and measures of academic productivity and success in mathematics. These results suggest that the AMS represents a reliable and valid tool for assessing attitudes towards mathematics.

Spatial and temporal synchronicity in the phenological events of Prosopis flexuosa in the Central Monte Desert; Sincronización espacial y temporal de los eventos fenológicos de Prosopis flexuosa en el Desierto del Monte Central Debandi, Guillermo; Rossi, Bertilde Elda; Villagra, Pablo Eugenio; Giantomassi, M.A.; Mantován, Nancy G. Some desert plant species are capable of using underground water and are therefore independent of rainfall events. Species of the genus Prosopis are thought to be facultative phreatophytes, since they have deep and shallow roots that allow them explore water from underground layers and from sub-surface soil horizons. We created a seven-year series of phenological data in order to make comparisons between two natural Reserves of Mendoza province (Ñacuñán and Telteca) with different rainfall regimes and accessibility of Prosopis flexuosa trees to water. Percentage of trees in each phenological phase, date of maximum expression, and intensity of each phenological phase were recorded. We found that the trees had a similar date for leafing and flowering across years and sites, even with very different rainfall regimes. However, pod maturation dates varied significantly, ocurring 37 days sooner in Telteca. A second peak of leaves and flowers were recorded at both sites, being highly variable and non-synchronous in most cases, suggesting a quick response to rainfall events. The ability of P. flexuosa to respond to unpredictable rainfall pulses could be an important adaptation to keep ecosystem services functioning, even though associated pollinators and seed dispersers could get decoupled from changes in phenological events.; Algunas plantas desérticas pueden utilizar agua subterránea volviéndose independientes de los eventos de lluvia. Se cree que las especies de Prosopis son freatófitas facultativas ya que tienen raíces profundas y superficiales que les permiten explorar capas subterráneas y sub-superficiales del suelo en busca de agua. Creamos una serie de datos fenológicos de siete años para comparar dos Reservas naturales de la provincia de Mendoza (Ñacuñán y Telteca) con diferentes regímenes de precipitación y accesibilidad de Prosopis flexuosa al agua. Se registraron: porcentaje de árboles en cada fase fenológica, fecha de máxima expresión, e intensidad de cada fase fenológica. El inicio del desarrollo de hojas y flores fue similar a través de años y sitios, incluso con diferentes regímenes de lluvia. La fecha de maduración de los frutos sin embargo, fue significativamente (37 días) más corto en Telteca. Una segunda cohorte de hojas y flores, muy variable y no sincrónica en la mayoría de los casos, se registró en ambos sitios, sugiriendo una rápida respuesta a pulsos de lluvia. Esta capacidad de respuesta de P. flexuosa puede jugar un papel importante al mantener funcionando los servicios ecosistémicos, aunque los polinizadores y dispersores de semillas asociados podrían desacoplarse de los eventos fenológicos.

Tetraodontiformes (Osteichthyes, Actinopterygii) from the Miocene of Argentina: With the southernmost record of fossil Tetraodontidae; Tétraodontiformes (Osteichthyes, Actinopterygii) du Miocène d’Argentine: Avec la plus méridionale des occurrences de Tetraodontidae fossiles Gouiric Cavalli, Soledad; Azpelicueta, María de las Mercedes; Cione, Alberto Luis Teleostean evolution produced enormous variation in tooth morphology. This variation is related to the exploration and exploitation of very diverse dietary niches. Among extant fishes, several taxa of the order Tetraodontiformes (e.g. pufferfishes, porcupinefishes and ocean sunfishes) have evolved highly specialized beak-like tooth structures. Here we provide the first description of tetraodontiform crushing beaks from Argentina. A single complete premaxillary beak recovered from the early Miocene Gaiman Formation in Chubut Province is assigned to Molidae based on its premaxillaries being completely fused to one another along the midline, general morphology, and size. Moreover, due to the putative presence of rows of teeth fused to the thick and massive bone structure, the specimen might belong to the genus Ranzania Nardo, 1840. Several premaxillary beaks recovered in the late Miocene Paraná Formation of Entre Ríos Province are assigned to Tetraodontidae Bonaparte, 1832 based on the presence of long, slender, rod-like, and parallel dental units; premaxillae not fused in the midline but articulated by interlocking emarginations, and a few small and one large trituration dental units. Argentinian tetraodontiform fishes inhabited the warm-temperate Paranense and Patagoniense Seas (marine transgressions developed in southeastern South America) during the early-late Miocene; these specimens are the southernmost fossil record of the group worldwide. Tetraodontiforms are extremely rare in recent Argentinian marine waters. The new fossil records agree with the higher sea water surface temperatures suggested both locally and worldwide for the Miocene.; L’évolution des Téléostéens a produit une variation énorme dans la morphologie dentaire. Cette variation est à mettre en relation avec l’exploration et l’exploitation de niches alimentaires très diverses. Parmi les poissons actuels, plusieurs familles de l’ordre des Tétraodontiformes (à savoir poissons globe, poissons porc-épic et poissons lune) ont des structures dentaires très évoluées, en forme de bec. Nous donnons ici la première description de becs triturants de tétraodontiformes d’Argentine. Un unique bec complet prémaxillaire du Miocène inférieur à moyen de la formation Gaiman dans la province de Chubut a été assigné aux Molidae, sur la base de prémaxillaires complètement fusionnés l’un dans l’autre le long de la ligne médiane, de la morphologie et de la taille. De plus, en raison de la présence présumée de rangées de dents amalgamées à la structure osseuse massive et épaisse, le spécimen pourrait appartenir au genre Ranzania Nardo, 1840. Plusieurs becs prémaxillaires récoltés dans le Miocène moyen-supérieur de la formation Paraná dans la province d’Entre Rios sont assignés aux Tétraodontidae Bonaparte, 1832 sur la base de la présence d’unités dentaires parallèles, longues et minces en forme de baguette; de prémaxillaires non fusionnés dans la ligne médiane mais articulés par des émarginations imbriquées, et quelques petites et une grande unités dentaires triturantes. Les poissons tétraodontiformes argentins ont vécu dans les mers Paranense et Patagoniense tempéréeschaudes (transgressions marines développées dans le sud-est de l’Amérique du Sud); ces spécimens constituent le signalement de ce groupe fossile le plus méridional au monde. Les Tétraodontiformes sont extrêmement rares dans les eaux marines récentes d’Argentine. Les nouveaux signalements fossiles plaident en faveur de plus hautes températures des eaux marines superficielles, suggérées à la fois localement et mondialement au Miocène.