The sciences and applications of the Electron LINAC-driven neutron source in Argentina Granada, Jose Rolando; Mayer, R. E.; Dawidowski, Javier; Santisteban, Javier Roberto; Cantargi, F.; Blostein, Juan Jeronimo; Rodriguez Palomino, Luis Alberto; Tartaglione, Aureliano The Neutron Physics group at Centro Atómico Bariloche (CNEA, Argentina) has evolved for more than forty five years around a small 25MeV linear electron accelerator. It constitutes our compact accelerator-driven neutron source (CANS), which is dedicated to the use and development of neutronic methods to tackle problems of basic sciences and technological applications. Its historical first commitment has been the determination of the total cross sections of materials as a function of neutron energy by means of transmission experiments for thermal and sub-thermal neutrons. This also allowed testing theoretical models for the generation of scattering kernels and cross sections. Through the years, our interests moved from classic pulsed neutron diffraction, which included the development of high-precision methods for the determination of very low hydrogen content in metals, towards deep inelastic neutron scattering (DINS), a powerful tool for the determination of atomic momentum distribution in condensed matter. More recently non-intrusive techniques aimed at the scanning of large cargo containers have started to be developed with our CANS, testing the capacity and limitations to detect special nuclear material and dangerous substances. Also, the ever-present “bremsstrahlung” radiation has been recognized and tested as a useful complement to instrumental neutron activation, as it permits to detect other nuclear species through high-energy photon activation. The facility is also used for graduate and undergraduate students’ experimental work within the frame of Instituto Balseiro Physics and Nuclear Engineering courses of study, and also MSc and PhD theses work.

Foraging by burrowing parrots has little impact on agricultural crops in northeastern Patagonia, Argentina Sanchez, Rocio; Ballari, Sebastián A.; Bucher, Enrique H.; Masello, Juan F. Conflicts between wildlife and agriculture have increased as cultivation has expanded into previously unexploited areas. As frequent consumers of such crops, parrots (Psittaciformes) are often persecuted, despite the lack of measured economic impacts they may cause. This situation has compromised attempts to manage potential damage and endangered parrot populations. Here, we evaluate and measure actual crop damage and characterize the foraging areas used by the burrowing parrot (Cyanoliseus patagonus) in northeastern Patagonia, Argentina. We found that damage to field crops was economically insignificant, affecting 0.1%–0.4% of the sunflower harvest, with no damage detected in other more important crops in the region. The parrots mainly consumed grain left or spilled after harvesting, and unharvested grain from cultivated pastures and road margins. This grain represents a loss attributable to harvest machines, being independent from the presence of parrots. Given the negligible damage measured here, we conclude that there is no need for management of parrots as crop pests in northeastern Patagonia. Our study provides further support to the view that parrot damage has been often exaggerated and overstated.

Cranial development and directional asymmetry in Commerson?s dolphin, Cephalorhynchus commersonii commersonii: 3D geometric morphometric approach del Castillo, Daniela Laura; Segura Gago, Alda Valentina; Flores, David Alfredo; Cappozzo, Humberto Luis La tonina overa, Cephalorhynchus commersonii , es una de las especies de odontocetos más pequeñas. El objetivo de este trabajo fue estudiar la ontogenia craneana postnatal de esta especie a través de técnicas de morfometría geométrica, analizando la ontogenia postnatal de la componente simétrica y asimétrica de la forma, considerando el posible dimorfismo sexual en forma y tamaño del cráneo. Se digitalizaron 57 landmarks en una muestra de 139 cráneos. Los resultados obtenidos indicaron que C. commersonii presenta dimorfismo sexual en el tamaño del cráneo en ejemplares adultos, mientras que no se detectó dimorfismo sexual ligado a la forma. Los principales cambios de forma entre juveniles y adultos estuvieron ligados al alargamiento del rostro y a la acentuación del telescopamiento, como se ha observado en otros odontocetos. Se encontró que el nivel de asimetría direccional tiene un cambio sutil pero significativo durante la ontogenia, lo que podría tener implicancias funcionales. Se observó, como tendencia general, una variación de forma moderada durante la ontogenia postnatal, evidencia que apoya la hipótesis de que los adultos de esta especie retienen caracteres juveniles. En concordancia con estos resultados, se encontró que se alcanzó muy tempranamente la estabilidad en la forma y en el tamaño del cráneo, y no se detectaron diferencias en estos valores para machos y hembras. Las diferencias en patrones de forma y de crecimiento craneales en C. commersonii y P. blainvillei pueden estar asociados funcionalmente a modos específicos de alimentación, lo que también sugiere diferencias en la morfología de melón.; Commerson’s dolphin, Cephalorhynchus commersonii , is one of the smallest species of odontocete cetaceans. We aimed to study the postnatal cranial ontogeny of C. commersonii through geometric morphometric technique, analyzing the postnatal ontogeny of the symmetric and asymmetric components of shape and providing information about sexual dimorphism affecting cranial shape and size. We digitized 57 landmarks in a sample of 139 crania of an ontogenetic series. Our results indicate that C. commersonii presents sexual size dimorphism of cranium in adults, but not shape dimorphism. Major changes between juveniles and adults were associated with lengthening of the rostrum and accentuation of telescoping, as observed in other odontocetes. We found that the degree of asymmetry has a very subtle but still significant change during ontogeny, which may have functional implications. We also observed little general variation in skull shape during postnatal development, supporting the idea of the conservatism of young-like characters in adults of C. commersonii . In accordance with this, we detect a very early attainment of stability of shape and size, being statistically similar in males and females. Differences in overall cranial shape and growth patterns in C. commersonii and Pontoporia blainvillei can be functionally associated to specific modes of feeding, suggesting also differences in the melon morphology.

Recorredores de mundos: viajeros nativos en las pampas y Araucanía (siglos XVIII y XIX); Travelers of Worlds: Native Travelers in the Pampas and the Araucanía (XVIIIth and XIXth Centuries) Jiménez, Juan Francisco; Alioto, Sebastián Leandro En América, viajero remite generalmente a un europeo o criollo que se aventuraba por espacios desconocidos y riesgosos, registrando sus vivencias por escrito. No se concibe la imagen de indígenas que viajasen, aunque fueron numerosos los que recorrían las pampas y la cordillera en la época considerada (siglos XVIII y XIX), y se enfrentaban con tres clases de dificultades principales: las propias del paisaje o medio físico, las condiciones cambiantes generadas por la fragmentación de los escenarios políticos y las interacciones con los seres sobrenaturales. A través de diversos tipos de fuentes éditas e inéditas se analizarán las condiciones en las que los nativos transitaban estas regiones procurándose seguridad y alojamiento y construyendo una red de relaciones sociales que los sostuvieran a lo largo del camino.; In America, traveler usually refers to a European or criollo who ventured through unknown and risky spaces, recording their experiences in writing. It is not conceived that there were traveling Indians, though there were a great number of native travelers who toured the pampas and the Andes in the XVIII and XIX centuries, and faced three main difficulties: the ones inherent to the landscape or physical environment, the changing conditions generated by the fragmentation of political scenarios, and the interactions with the super-natural beings. Through diverse edited and unedited sources, we analyze the conditions in which natives moved across these regions trying to procure safety and lodging, and building a network of social relationships that supported them along the way.

Generación de biomasa y rendimiento en trigo frente a infecciones de Puccinia triticina y Pyrenophora tritici-repentis; Wheat biomass and yield generation under Puccinia triticina and Pyrenophora tritici-repentis infections. Schierenbeck, Matías; Fleitas, María Constanza; Golik, Silvina Ines; Simón, María Rosa El objetivo del presente trabajo fue evaluar el efecto de un patógeno fúngico biotrófico (Puccinia triticina), causal de la roya de la hoja (RH) y un necrotrófico (Pyrenophora tritici-repentis), causal de la mancha amarilla (MA) sobre los atributos fisiológicos vinculados a la generación de biomasa y rendimiento en trigo. Se condujo un ensayo durante 2012 y 2013 utilizando un diseño experimental en parcela sub-dividida con tres repeticiones. Las parcelas principales fueron las inoculaciones con los patógenos. Las sub-parcelas fueron: 1-Sin inóculo y aplicación de fungicida, 2-baja concentración de inóculo y 3-alta concentración de inóculo. Como sub-sub-parcela se sembraron 10 cultivares de trigo. Los resultados indican que MA afectó más la absorción de radiación a partir de mayores niveles de senescencia foliar, en tanto que RH afectó más la eficiencia en el uso de la radiación, probablemente por la interacción particular que los patógenos biotróficos presentan con las células del hospedante.; The present study was designed to determine the effects of inoculations of foliar disease pathogens with different nutritional habits: Pyrenophora tritici-repentis (necrothroph -PTR-) and Puccinia triticina (biotroph -LR-) on the physiological components of biomass generation, like absorbed photosynthetic active radiation (APAR) and radiation use efficiency (RUE), and on the yield production in wheat. Field experiments were carried out in 2012-2013 at FCAyF-UNLP using a split-split-plot design with three replications. The main plots were the pathogen inoculations. Subplots were inoculation treatments: 1- Without inoculation, 2- Low dose of spores concentration inoculation, 3- High dose of spores concentration. Ten cultivars were the sub-subplots. Foliar diseases decreased biomass production mainly explained by reductions in green leaf area, healthy area duration and reductions on APAR, showing higher declines under PTR inoculations. A detrimental effect in the RUE was detected at LR inoculations, which could be associated with the nutritional habit of the pathogen.

An All-Sky Search for Three Flavors of Neutrinos from Gamma-Ray Bursts with the IceCube Neutrino Observatory Aartsen, M.G.; Abraham, K.; Ackermann, M.; Adams, J.; Aguilar, J.A.; Ahlers, M.; Ahrens, M.; Altmann, D.; Anderson, T.; Ansseau, I.; Anton, G.; Archinger, M.; Arguelles, C.; Arlen, T.C.; Auffenberg, J.; Bai, X.; Barwick, S.W.; Baum, V.; Bay, R.; Beatty, J.J.; Tjus, J. Becker; Becker, K.-H.; Beiser, E.; Benzvi, S.; Berghaus, P.; Berley, D.; Bernardini, E.; Bernhard, A.; Besson, D.Z.; Binder, G.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D.J.; Bohm, C.; Börner, M.; Bos, F.; Bose, D.; Böser, S.; Botner, O.; Braun, J.; Brayeur, L.; Bretz, H.-P.; Buzinsky, N.; Casey, J.; Casier, M.; Cheung, E.; Chirkin, D.; Christov, A.; Clark, K.; Classen, L.; Coenders, S.; Collin, G.H.; Conrad, J.M.; Cowen, D.F.; Cruz Silva, A.H.; Daughhetee, J.; Davis, J.C.; Day, M.; De André, J.P.A.M.; De Clercq, C.; Del Pino Rosendo, E.; Dembinski, H.; De Ridder, S.; Desiati, P.; De Vries, K.D.; De Wasseige, G.; De With, M.; Deyoung, T.; Díaz-Vélez, J.C.; Di Lorenzo, V.; Dujmovic, H.; Dumm, J.P.; Dunkman, M.; Eberhardt, B.; Ehrhardt, T.; Eichmann, B.; Euler, S.; Evenson, P.A.; Fahey, S.; Fazely, A.R.; Feintzeig, J.; Felde, J.; Filimonov, K.; Finley, C.; Flis, S.; Fösig, C.-C.; Fuchs, T.; Gaisser, T.K.; Gaior, R.; Gallagher, J.; Gerhardt, L.; Ghorbani, K.; Gier, D.; Gladstone, L.; Glagla, M.; Glüsenkamp, T.; Goldschmidt, A.; Golup, Geraldina Tamara; Gonzalez, J.G.; Góra, D.; Grant, D.; Griffith, Z.; Ha, C.; Haack, C.; Haj Ismail, A.; Hallgren, A.; Halzen, F.; Hansen, E.; Hansmann, B.; Hansmann, T.; Hanson, K.; Hebecker, D.; Heereman, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hignight, J.; Hill, G.C.; Hoffman, K.D.; Hoffmann, R.; Holzapfel, K.; Homeier, A.; Hoshina, K.; Huang, F.; Huber, M.; Huelsnitz, W.; Hulth, P.O.; Hultqvist, K.; In, S.; Ishihara, A.; Jacobi, E.; Japaridze, G.S.; Jeong, M.; Jero, K.; Jones, B.J.P.; Jurkovic, M.; Kappes, A.; Karg, T.; Karle, A.; Katz, U.; Kauer, M.; Keivani, A.; Kelley, J.L.; Kemp, J.; Kheirandish, A.; Kim, M.; Kintscher, T.; Kiryluk, J.; Klein, S.R.; Kohnen, G.; Koirala, R.; Kolanoski, H.; Konietz, R.; Köpke, L.; Kopper, C.; Kopper, S.; Koskinen, D.J.; Kowalski, M.; Krings, K.; Kroll, G.; Kroll, M.; Krückl, G.; Kunnen, J.; Kunwar, S.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Lanfranchi, J.L.; Larson, M.J.; Lennarz, D.; Lesiak-Bzdak, M.; Leuermann, M.; Leuner, J.; Lu, L.; Lünemann, J.; Madsen, J.; Maggi, G.; Mahn, K.B.M.; Mandelartz, M.; Maruyama, R.; Mase, K.; Matis, H.S.; Maunu, R.; McNally, F.; Meagher, K.; Medici, M.; Meier, M.; Meli, A.; Menne, T.; Merino, G.; Meures, T.; Miarecki, S.; Middell, E.; Mohrmann, L.; Montaruli, T.; Morse, R.; Nahnhauer, R.; Naumann, U.; Neer, G.; Niederhausen, H.; Nowicki, S.C.; Nygren, D.R.; Obertacke Pollmann, A.; Olivas, A.; Omairat, A.; O'Murchadha, A.; Palczewski, T.; Pandya, H.; Pankova, D.V.; Paul, L.; Pepper, J.A.; Pérez De Los Heros, C.; Pfendner, C.; Pieloth, D.; Pinat, E.; Posselt, J.; Price, P.B.; Przybylski, G.T.; Quinnan, M.; Raab, C.; Radel, L.; Rameez, M.; Rawlins, K.; Reimann, R.; Relich, M.; Resconi, E.; Rhode, W.; Richman, M.; Richter, S.; Riedel, B.; Robertson, S.; Rongen, M.; Rott, C.; Ruhe, T.; Ryckbosch, D.; Sabbatini, L.; Sander, H.-G.; Sandrock, A.; Sandroos, J.; Sarkar, S.; Schatto, K.; Schimp, M.; Schlunder, P.; Schmidt, T.; Schoenen, S.; Schöneberg, S.; Schönwald, A.; Schumacher, L.; Seckel, D.; Seunarine, S.; Soldin, D.; Song, M.; Spiczak, G.M.; Spiering, C.; Stahlberg, M.; Stamatikos, M.; Stanev, T.; Stasik, A.; Steuer, A.; Stezelberger, T.; Stokstad, R.G.; Stößl, A.; Ström, R.; Strotjohann, N.L.; Sullivan, G.W.; Sutherland, M.; Taavola, H.; Taboada, I.; Tatar, J.; Ter-Antonyan, S.; Terliuk, A.; Te?i?, G.; Tilav, S.; Toale, P.A.; Tobin, M.N.; Toscano, S.; Tosi, D.; Tselengidou, M.; Turcati, A.; Unger, E.; Usner, M.; Vallecorsa, S.; Vandenbroucke, J.; Van Eijndhoven, N.; Vanheule, S.; Van Santen, J.; Veenkamp, J.; Vehring, M.; Voge, M.; Vraeghe, M.; Walck, C.; Wallace, A.; Wallraff, M.; Wandkowsky, N.; Weaver, Ch.; Wendt, C.; Westerhoff, S.; Whelan, B.J.; Wiebe, K.; Wiebusch, C.H.; Wille, L.; Williams, D.R.; Wills, L.; Wissing, H.; Wolf, M.; Wood, T.R.; Woschnagg, K.; Xu, D.L.; Xu, X.W.; Xu, Y.; Yanez, J.P.; Yodh, G.; Yoshida, S.; Zoll, M. We present the results and methodology of a search for neutrinos produced in the decay of charged pions created in interactions between protons and gamma-rays during the prompt emission of 807 gamma-ray bursts (GRBs) over the entire sky. This three-year search is the first in IceCube for shower-like Cherenkov light patterns from electron, muon, and tau neutrinos correlated with GRBs. We detect five low-significance events correlated with five GRBs. These events are consistent with the background expectation from atmospheric muons and neutrinos. The results of this search in combination with those of IceCube's four years of searches for track-like Cherenkov light patterns from muon neutrinos correlated with Northern-Hemisphere GRBs produce limits that tightly constrain current models of neutrino and ultra high energy cosmic ray production in GRB fireballs.

Temporal changes in the expression of the translocator protein TSPO and the steroidogenic enzyme 5a-reductase in the dorsal spinal cord of animals with neuropathic pain: effects of progesterone administration Coronel, Maria Florencia; Sánchez Granel, María Luz; Raggio, María Celeste; Adler, Natalia Sol; de Nicola, Alejandro Federico; Labombarda, Maria Florencia; Gonzalez, Susana Laura Neuropathic pain is a frequent complication of spinal cord injury (SCI), still refractory to conventional treatment. The presence and biological activity of steroidogenic regulatory proteins and enzymes in the spinal cord suggests that neurosteroids locally generated could modulate pain messages. In this study we explored temporal changes in the spinal expression of the 18kDa translocator protein TSPO, the steroidogenic acute regulatory protein (StAr) and the steroidogenic enzyme 5-reductase (5α-RI/II) in an experimental model of central chronic pain. Male Sprague-Dawley rats were subjected to a SCI and sacrificed at different time points (1, 14 or 28 days). The development of mechanical and cold allodynia was assessed. Injured animals showed an early increase in the mRNA levels of TSPO and 5α-RII, whereas in the chronic phase a significant decrease in the expression of 5α-RI and 5α-RII was observed, coinciding with the presence of allodynic behaviors. Furthermore, since we have shown that progesterone (PG) administration may offer a promising perspective in pain modulation, we also evaluated the expression of steroidogenic proteins and enzymes in injured animals receiving daily injections of the steroid. PG-treated did not develop allodynia and showed a marked increase in the mRNA levels of TSPO, StAR, 5α-RI and 5α-RII 28 days after injury. Our results suggest that in the acute phase after SCI, the increased expression of TSPO and 5α-RII may represent a protective endogenous response against tissue injury, which is not maintained in the chronic allodynic phase. PG may favor local steroidogenesis and the production of its reduced metabolites, which could contribute to the antiallodynic effects observed after PG treatment. 

Sex and reproductive cycle affect lipid and fatty acid profiles of gonads of Arbacia dufresnii (Echinodermata: Echinoidea) Zárate, Erica; Díaz de Vivar, María Enriqueta Adela; Avaro, Marisa Gladis; Epherra, Lucía; Sewell, Mary A. Analysis of the lipid composition of gonads allows differentiation between energy and structural lipids, which is important for understanding lipid utilization during gametogenesis. Fatty acids, which are frequently used as biomarkers in trophic ecology studies, are also a useful companion to lipid studies and provide a detailed understanding of a species' reproductive cycle. We examined the influence of sex and the reproductive cycle on the lipid and fatty acid profiles of gonads in the sea urchin Arbacia dufresnii. In a population from Nuevo Gulf, Argentina, we found significant changes in total lipid concentration, lipid profile and fatty acid profile throughout the reproductive cycle. Ovaries and testes containing fully mature gametes differed in total lipid concentration (higher in the ovaries), lipid profile (more energy lipids in ovaries and more structural lipids in testes) and fatty acid profile (differed by sex, not only in the variety of fatty acids present but in the degree of unsaturation). Our results show that differences in lipid and fatty acid profiles caused by sex and gonadal reproductive stage need to be considered when these tools are used as biomarkers in ecological studies.

Introduction to special issue: Mycorrhizas and Global Change Karst, Justine; Urcelay, Roberto Carlos

First report of Lernaea cyprinacea (Copepoda: Lernaeidae) in tadpoles and newly-metamorphosed frogs in wild populations of Lithobates catesbeianus (Anura: Ranidae) in Argentina; Primeiro relato de Lernaea cyprinacea (Copepoda: Lernaeidae) em girinos e rãs recémmetamorfoseadas em populações selvagens de Lithobates catesbeianus (Anura: Ranidae) na Argentina Salinas, Zulma Anahí; Biolé, Fernanda Gabriela; Grenat, Pablo Raúl; Pollo, Favio Ezequiel; Salas, Nancy Edith; Martino, Adolfo Ludovico Lernaea cyprinacea is an ectoparasitic copepod that can result in the mortality of the host by causing hemorrhages, ulcerations, and secondary infections. Lernaea cyprinacea is widely distributed in Argentina. Previous reports are restricted almost exclusively to cases of parasitism in fishes; copepod parasitism of anuran larvae is rarely documented. This is the first record and description of the parasitic infestation of L. cyprinacaea on tadpoles of the exotic and invasive species Lithobates catesbeianus in Argentina. A total of 15 tadpoles and 21 newly-metamorphosed individuals of L. catesbeianus were collected from the mountain town of Rio de los Sauces, and 12 tadpoles from the Toledo Stream. A maximum of two parasites per host was found, principally in the cloaca. Clinical symptoms of inflammation hemorrhage and ulcers in the skin with mucus formation in the attachment area of parasites were observed.; Lernaea cyprinacea é um copépode ectoparasita que pode causar a morte do hospedeiro devido as hemorragias, ulceraçoes e infecçoes secundárias que provoca. Lernaea cyprinacea está amplamente distribuida na Argentina. Os relatos anteriores estao restritos quase que exclusivamente a casos de parasitismo em peixes; o parasitismo de larvas de anuros por copépodes tem sido raramente documentado. Este é o primeiro registro e descriçao da infestaçao parasitária de L. cyprinacaea em girinos da espécie exótica e invasora Lithobates catesbeianus na Argentina. Um total de 15 girinos e 21 individuos recém-metamorfoseados de L. catesbeianus foi coletado na regiao serrana do Rio de los Sauces, e 12 girinos, no córrego Toledo. Foi encontrado um máximo de dois parasitas por hospedeiro, principalmente na cloaca. Foram observados sintomas clinicos de hemorragia, inflamaçao e ülceras na pele, com formaçao de muco na área de fixaçao dos parasitas.

Paraguay: pasado y presente. Una revisión desde la historia política López, Magdalena Este artículo se constituye en una reflexión desde la historia política sobre el Paraguay contemporáneo, con la intención comprender los factores que influyeron en la conformación y modelación de la democracia paraguaya actual. Tras repasar críticamente fenómenos sociales, políticos y económicos, pretendemos trazar un rastro que nos permita comprender el desenlace de la Masacre de Curuguaty, piedra fundamental para el montaje del Juicio Político (popularmente conocido como Golpe Parlamentario) mediante el cual se destituyó a Fernando Lugo. Este trabajo revisa la información previa, ensamblando sucesos ("hitos") históricos que pueden servir como indicios para analizar el presente político paraguayo.; This article constitutes a reflection from the perspective of political history of Paraguay, with the intention to understand the factors that have influenced over the creation and modeling of the current Paraguayan democracy. After critically reviewing social, political and economic phenomena, we intend to trace a trail that allows us to understand the outcome of the Masacre de Curuguaty, essential for the assembly of Impeachment (popularly known as Parliamentary Coup d’État) by which Fernando Lugo was dismissed. This work revises previous information, connecting historical events ("milestones") that can serve as evidence to analyze the Paraguayan political present.

Auxiliary inductances design of a bidirectional three-port DC-DC converter Piris Botalla, Laureano Enrique; Oggier, German Gustavo; Garrido, Daniel Oscar; Garcia, Guillermo This paper proposes a methodology to design the auxiliary inductances of a bidirectional three-port DC-DC converter, which allows minimize the currents through the high frequency transformer and switches. In this way, RMS current and also the current values at the switching instants, as function of auxiliary inductances, are analyzed considering the different operating conditions. From this analysis, design considerations for these inductances are determined. Finally, experimental results are presented to validate the theory.

60º Aniversario del Instituto Balseiro Abramson, Guillermo Durante 2015 los graduados del Instituto Balseiro celebraron el 60º aniversario de su alma mater, tan ligada al crecimiento social, cultural e industrial de Bariloche. Los festejos culminaron en diciembre con una reunión científica que convocó a centenares de egresados, muchos de ellos de lugares lejanos del mundo. Como parte de estas actividades se realizó una sesión de divulgación científica abierta a toda la comunidad de Bariloche, que tuvimos el agrado de llevar a cabo en el Aula Mayor del Centro Regional Universitario Bariloche, una institución con vínculos académicos de larga data con nuestro Instituto. La sesión contó con la participación de destacados egresados como oradores, doctores en Física y activos divulgadores de la ciencia compartiendo el evento con un público ávido. En estas páginas se presentan en forma de breves textos dos charlas fantásticas, entretenidas y enriquecedoras: acerca de los griegos y sus vidas trágicas de la mano de Miguel Hoyuelos, y sobre la antimateria, la magia y la poesía, a cargo de José Edelstein.

Spaces for transdisciplinary dialogues on the relationship between local communities and their environment: The case of a rural community in the calchaquí valley (Salta, Argentina) Crivos, Marta Alicia; Martínez, María Rosa; Teves, Laura Susana; Remorini, Carolina Our ethnographic research focuses on the perception and use of components of the natural environment in terms of routine activities carried out by the residents of a rural community in the Calchaqui Valley (Salta, Argentina). Life in this community is characterised by the presence of traditional subsistence activities – agriculture, cattle farming, textile manufacturing and ancestral medical practices – coexisting with business ventures focused on monoculture and export, tourism centred on landscape intervention and promotion of native products, and the growing key role of public policies in the areas of health and human development. In this context, a joint reflection on viability and sustainability of local and global practices and resources must be undertaken. Implementing intersectoral forums and focus-group discussions, governmental and non-governmental actors, researchers and local people must work conjointly to achieve a fresh patrimonial awareness of livelihood strategies based on their long interaction with a specific environment.

Tiling the plane with different hexagons and triangles Panzone, Pablo Andres We prove that the plane can be tiled with equilateral triangles and regular hexagons of integer sides using exactly one of each family.

Los primeros pasos en la organización de la lucha contra el cáncer en la Argentina: el papel del Instituto de Medicina Experimental, 1922-1947; The begginings of the fight against cancer in argentina: the role of the instituto de medicina experimental, 1922-1947 Buschini, Jose Daniel El artículo analiza iniciativas para organizar la lucha contra el cáncer en la Argentina entre comienzos de la década de 1920 y mediados de la década de 1940. En particular, hace eje en las acciones del Instituto de Medicina Experimental, un hospital-instituto de investigación dependiente de la Facultad de Ciencias Médicas de la Universidad de Buenos Aires que tuvo un papel central en este proceso. Se presta atención a la organización de la atención médica en el establecimiento, a las campañas de difusión de conocimiento a la población, a los intentos por incorporar esta cuestión a la formación profesional, a la articulación de las actividades con organismos estatales para dar mayor alcance territorial a la lucha contra el cáncer y a las investigaciones científicas que apuntaron a vincular el desarrollo del cáncer con estilos de vida.; This article analyses initiatives to organize the fight against cancer in Argentina between the early 1920s to mid 1940s. Specifically, it focuses on the initiatives of the Instituto de Medicina Experimental, a hospital-research institute dependent on the Facultad de Ciencias Médicas of the Universidad de Buenos Aires that played a key role in this process. This paper considers the organization of the medical attention within the establishment, knowledge awareness campaigns, and the intents to incorporate cancer as a topic in the professional curricula and scientific research linking cancer and life styles.

Heterogeneous catalysis for valorisation of vegetable oils via metathesis reactions: Ethenolysis of methyl oleate Nieres, Pablo Daniel; Zelin, Juan; Trasarti, Andres Fernando; Apesteguia, Carlos Rodolfo The cross-metathesis of methyl oleate (MO) with ethylene was studied on a second-generation Hoveyda?Grubbs complex supported on silica (HG/SiO2). The reaction was carried out in a batch slurry reactor at 313?353 K and 2.5?7.5 bar of C2H4(5%)/N2, using cyclohexane as a solvent. The MO ethenolysis productswere methyl 9-decenoate and 1-decene. The competitive MO self-metathesis reaction formed 9-octadecene and methyl 9-octadecen-1,18-dioate. The yield (YE) and selectivity (SE) for ethenolysis products at PC2H4 = 0.125 bar (total pressure = 2.5 bar) were 52% and 69%, respectively. Both parameters increasedwith PC2H4, essentially because the reaction equilibrium was shifted to higher methyl oleate conversions. Thus, at PC2H4 = 0.250 bar, the YE and SE values were 63% and 77%, respectively. Nevertheless, catalyst deactivation was observed for ethylene pressures higher than 0.125 bar, thereby suggesting that the presence of ethylene may suppress the metathesis cycle on HG/SiO2 catalysts. The ethenolysis product yield decreased when the temperature was increased, reflecting mainly the MO equilibrium conversion diminution.

Risk factors associated with the presence of aflatoxin M1 in raw bulk milk from Argentina Michlig, Nicolás; Signorini, Marcelo; Gaggiotti, Mónica del Carmen; Chiericatti, Carolina Andrea Antonia; Basilico, Juan Carlos; Repetti, María Rosa; Beldomenico, Horacio Ramon The objectives of this study were to assess aflatoxin M1 (AFM1) contamination in bulk tank milk, and to further identify the risk factors associated with the presence of AFM1 in raw milk in Argentina. The presence of AFM1 was investigated in 160 bulk tank milk samples collected from farms located in the most important milk production region in Argentina during one year (four seasons). Samples wereanalysed using immunoaffinity column (IAC) cleanup and UHPLC-MS/MS method for determining AFM1 at low levels of concentrations (LOQ ¼ 0.003 mg L1). A survey about the potential factors associated with the presence of AFM1 in milk was performed directly in the field through a questionnaire applied to the farmers. Chi-square and logistic regression were performed with presence of AFM1 in milk as dependent variable, and potential risk factors as independent variables. Incidence of AFM1 in raw milk was 38.8% and, in all samples, AFM1 levels were lower than the Southern Common Market (MERCOSUR) Regulation (maximum level accepted ¼ 0.5 mg L1). Commercial feed consumption (OR ¼ 4.630, P ¼ 0.001), soybean expeller consumption (>0.95 kgDM/cow) (OR ¼ 3.542, P ¼ 0.019), and cotton seed consumption (>1.5 kgDM/cow) (OR ¼ 2.949, P ¼ 0.089) were associated with the incidence of AFM1 in raw milk. Despite the incidence and the level of AFM1 in milk produced and commercialized in Argentina is not a serious problem for public health. The farm breeding intensification and the supplementation with commercial feed, soybean expeller, and cotton seed seems to be the risk factors that impacts on the AFM1 milk contamination. Therefore, Argentina should improve its monitoring program on mycotoxins in animal feed and milk and improve the management practices in farms.

A diez años de la entrada en vigor de la Convención sobre la diversidad cultural: Desequilibrios en el mercado internacional de bienes y servicios culturales, y el desafío digital; Dix ans après l'entrée en vigueur de la Convention sur la diversité culturelle: Déséquilibres dans le marché international des biens et services culturels, et défi numérique; Ten years after the entry into force of the Convention on Cultural Diversity: Imbalances in the international market for cultural goods and services, and the digital challenge Albornoz, Luis Alfonso A casi una década de la entrada en vigor de la Convención sobre la diversidad de las expresiones culturales (Unesco, 2005) se impone conocer en qué medida este nuevo tratado internacional, que propugna un mayor equilibrio entre países desarrollados y países en desarrollo en materia cultural, ha logrado transformar los flujos internacionales de comercialización de bienes y servicios culturales. Basándose en datos de fuentes públicas (OMC, ISU) y privadas, el presente artículo demuestra el férreo dominio que continúan detentando las industrias culturales de los países desarrollados. Finalmente se considera la magnitud de uno de los grandes desafíos que hoy debe enfrentar la Convención: la concreción de sus postulados en el paisaje que dibujan las tecnologías digitales.; Près d'une décennie après l'entrée en vigueur de la Convention sur la diversité des expressions culturelles (Unesco, 2005) s’impose la nécessité de savoir dans quelle mesure ce nouveau traité international, qui appelle à un meilleur équilibre entre les pays développés et les pays en développement en matière culturelle, a réussi à transformer les flux internationaux du commerce des biens et services culturels. Sur la base des données provenant de sources publiques (OMC, ISU) et privées, cet article démontre le fort contrôle que continuent d'exercer les industries culturelles appartenant à des pays développés. Enfin, est envisagée l'ampleur de l'un des plus grands défis actuels de la Convention : la réalisation de ses principes dans le cadre de l’avancée des technologies numériques.; Almost a decade after the entry into force of the Convention on the Diversity of Cultural Expressions (Unesco, 2005) is imposed to know to what extent this new international treaty, which calls for a better balance in cultural matters between developed countries and developing countries, it has succeeded in transforming international flows of trade of cultural goods and services. Based on data from public (WTO, UIS) and private sources, this article demonstrates the strong control that cultural industries of developed countries still have nowadays. Finally, the following pages consider the magnitude of one of the great challenges that the Convention must face today: the realization of its principles in the landscape drawn by digital technologies.

Inventario de Perspectiva Temporal de Zimbardo: Adaptación en estudiantes de nivel medio de Buenos Aires; Zimbardo Time Perspective Inventory: Adaptation for high-schol students from Buenos Aires Galarraga, María Laura; Stover, Juliana Beatriz El objetivo del trabajo fue adaptar el Inventario de Perspectiva Temporal de Zimbardo a estudiantes de nivel medio de Buenos Aires. Se trabajó con 320 estudiantes de Buenos Aires (47.2% mujeres, 52.8% hombres; Medad =16.95, DEedad = 1.05). Se recolectaron datos con una encuesta de datos sociodemográficos y académicos y con el Inventario de Perspectiva Temporal de Zimbardo. Mediante un análisis de componentes principales con rotación Varimax se aisló una estructura de cuatro dimensiones (KMO = .80; Bartlett: X2 = 2567.88; 561gl) que explicó el 37.95% de la varianza total. Se etiquetaron las dimensiones como pasado negativo, presente hedonista, futuro y presente fatalista. Se estimó la consistencia interna mediante el cálculo de alfas de Cronbach, en donde se encontraron valores excelentes para pasado negativo (α = .80) y presente hedonista (α = .78), y adecuados para futuro (α = .68) y presente fatalista (α = .63). Se hallaron evidencias de validez de criterio en relación con información académica en el pasado (repitencia), presente (adeudar materias) y futuro (proyectos al egreso). Se calcularon percentiles para la evaluación individual del inventario. Se concluye que se ha elaborado un instrumento diseñado para evaluar estudiantes locales. Futuras investigaciones deberán continuar examinando la estructura dado que difiere de la propuesta en la versión original.; The objective of the work was to adapt the Zimbardo Temporary Perspective Inventory to medium level students from Buenos Aires. We worked with 320 students from Buenos Aires (47.2% women, 52.8% men; Medad = 16.95, DEedad = 1.05). Data were collected with a survey of sociodemographic and academic data and with the Zimbardo Temporal Perspective Inventory. A principal component analysis with Varimax rotation isolated a four-dimensional structure (KMO = .80; Bartlett: X2 = 2567.88; 561gl) that explained 37.95% of the total variance. Dimensions were labeled as negative past, hedonistic present, future, and fatalistic present. Internal consistency was estimated by calculating Cronbach's alphas, where excellent values ​​were found for negative past (α = .80) and hedonistic present (α = .78), and suitable for future (α = .68) and present fatalistic (α = .63). Evidence of criteria validity was found in relation to academic information in the past (repetition), present (owing subjects) and future (projects at graduation). Percentiles were calculated for the individual evaluation of the inventory. It is concluded that an instrument designed to evaluate local students has been developed. Future research should continue to examine the structure since it differs from that proposed in the original version.