Persistent effect of organic matter pulse on a sandy soil of semiarid Patagonia Gonzalez Polo, Marina; Kowaljow, Esteban; Castán, Elisa; Sauzet, Ophelie; Mazzarino, Maria Julia Studies of degraded semiarid regions have shown that organic residue addition is a sound restoration alternative. We examined the effects of a single dose (40 Mg ha−1) of biosolids compost (BC) and compost of the organic fraction of municipal solid waste (MC) 6 years after they were applied to a sandy soil of NW Patagonia. Results were compared with those of inorganic fertilization (IF, 100 kg N+35 kg P ha−1) treatment and of unamended control. We measured plant cover, biomass, and diversity and chemical, biological, and biochemical soil properties. We did not find any significant effect of treatments on plant attributes. However, effects on soil properties were significant and more persistent with composts than with IF, especially with BC, which had higher organic C and nutrients than MC. Total soil C and N were twice as high in the BC-amended soil as in the control and IF soils. Soil extractable P was 4-fold and 2-fold higher in BC and MC-treated soils, respectively, than in the control soil, and even higher than in the IF treatment in response to BC. The highest β-glucosidase and acid phosphomonoesterase activities were found in the BC-treated soil, related to higher C and P in the soil and to higher activities of both enzymes in the biosolids compost. The highest phenol oxidase activity was found in MC and in the MC-treated soil. Potential respiration and K2SO4-extractable C were higher in the compost-treated soil, but there was no difference in microbial biomass Cbetween the compost-treated and the control soils. Despite the fact that the soil was coarse textured and a single moderate dose of compost was applied, recovery of soil chemical, microbiological, and biochemical properties was long-lasting, indicating that application of urban compost is a feasible restoration practice in this semiarid region.

Phellinus piptadeniae (Hymenochaetales: Hymenochaetaceae): taxonomy and host range of a species with disjunct distribution in South American seasonally dry forests Salvador Montoya, Carlos Alberto; Robledo, Gerardo Lucio; Cardoso, Domingos; Borba Silva, Marco A.; Fernandes, Mariana; Drechsler Santos, Elisandro Phellinus piptadeniae (Hymenochaetaceae, Hymenochaetales) is traditionally characterized by having applanate to ungulate basidiome with the pilear surface concentrically sulcate, radially cracked in old specimens, and a notorious sinuous black line in the cross section of the context. The species has been recorded in different Brazilian biomes, often associated with legume hosts and seasonally dry vegetation. It occurs highly specifically associated with Piptadenia gonoacantha in semideciduous forest of the Atlantic Forest domain at the type locality in São Paulo state, southeastern Brazil. In the Caatinga dry woodlands, northeastern Brazil, Phellinus piptadeniae occurs as host-recurrent of different Piptadenia species. During a recent polypore survey in different remnants of southeastern Atlantic Forest, specimens with the same morphology of the type were collected and the same host (P. gonoacantha) was confirmed. Morphologically similar specimens newly collected in seasonally dry tropical forests of northwestern Peru were also recorded on legume hosts (Libidibia glabrata and Pithecellobium excelsum). In this paper we discuss the morphological variation, host range, and distribution of Phellinus piptadeniae in the context of the historical biogeography of the neotropical Seasonally Dry Tropical Forest (SDTF) biome. Some putative taxonomic implications that should be further investigated in a molecular phylogenetic framework are also addressed.

Native fish larvae take advantage of introduced mussel larvae: field evidence of feeding preferences on veligers of the introduced freshwater bivalve Limnopernafortunei Paolucci, Esteban Marcelo; Almada, Pablo; Cataldo, Daniel Hugo; Boltovskoy, Demetrio Previous work has shown that the invasive bivalve Limnoperna fortunei has had a measurable impact on local food webs, but knowledge of the trophic interactions involved is still very limited. On the basis of samples collected along the lower Paraguay-middle Parana´ rivers, we studied the feeding behavior and selectivity of larval fish, with emphasis on veligers of the introduced bivalve L. fortunei. Among feeding larvae (i.e., without a yolk sac), 16.5% had only Limnoperna veligers in their guts, while 15.6% had veligers and some other prey. Half of the fish taxa recorded (8 out of a total of 16) consumed Limnoperna veligers. The Paraguay and Parana´ rivers differed strongly in the proportions of fish larvae that consumed veligers: 14 and 68%, respectively. This difference paralleled the availability of veligers in the water column, which was significantly lower in the Paraguay (0.8 ± 0.5 ind. l-1 ) than in the Parana´ River (5.5 ± 2.3 ind. l-1 ). Conversely, cladocerans, originally the staple food of fish larvae, were more abundant in the Paraguay (consumed by 48% of the individuals) than in the Parana´ River (26%). These results indicate that, when widely available, Limnoperna veligers largely replace the original prey of fish larvae, especially in their younger stages (protolarvae).

Kerr geometry in f(T) gravity Bejarano, Cecilia Soledad; Ferraro, Rafael; Guzmán Monsalve, María José Null tetrads are shown to be a valuable tool in teleparallel theories of modified gravity. We use them to prove that Kerr geometry remains a solution for a wide family of theories of gravity.

Double ionization of helium by fast electrons with the Generalized Sturmian Functions method Ambrosio, Marcelo José; Colavecchia, Flavio Dario; Gasaneo, Gustavo; Mitnik, Dario Marcelo; Ancarani, L. U. The double ionization of helium by high energy electron impact is studied. The corresponding four-body Schrödinger equation is transformed into a set of driven equations containing successive orders in the projectile–target interaction. The first order driven equation is solved with a generalized Sturmian functions approach. The transition amplitude, extracted from the asymptotic limit of the first order solution, is equivalent to the familiar first Born approximation. Fivefold differential cross sections are calculated for (e, 3e) processes within the high incident energy and small momentum transfer regimes. The results are compared with other numerical methods, and with the only absolute experimental data available. Our cross sections agree in shape and magnitude with those of the convergent close coupling method for the (10+10) eV and (4+4) eV emission energies. To date this had not been achieved by any two different numerical schemes when solving the three–body continuum problem for the fast projectile (e, 3e) process. Though agreement with the experimental data, in particular with respect to the magnitude, is not achieved, our findings partly clarify a long standing puzzle.

Admixture and genetic relationships of Mexican Mestizos regarding Latin American and Caribbean populations based on 13 CODIS-STRs Salazar Flores, J.; Zuniga Chiquette, F.; Rubi Castellanos, R.; Álvarez Miranda, J. L.; Zetina Hérnandez, A.; Martínez Sevilla, V. M.; González Andrade, F.; Corach, Daniel; Vullo, C.; Álvarez, J. C.; Lorente, J. A.; Sánchez Diz, P.; Herrera, R. J.; Cerda Flores, R. M.; Muñoz Valle, J. F.; Rangel Villalobos, H. Short tandem repeats (STRs) of the combined DNA index system (CODIS) are probably the most employed markers for human identification purposes. STR databases generated to interpret DNA profiles are also helpful for anthropological purposes. In this work, we report admixture, population structure, and genetic relationships of Mexican Mestizos with respect to Latin American and Caribbean populations based on 13 CODIS-STRs. In addition, new STR population data were included from Tijuana, Baja California (Northwest, Mexico), which represents an interesting case of elevated genetic flow as a bordering city with the USA. Inter-population analyses included CODIS-STR data from 11 Mexican Mestizo, 12 Latin American and four Caribbean populations, in addition to European, Amerindian, and African genetic pools as ancestral references. We report allele frequencies and statistical parameters of forensic interest (PD, PE, Het, PIC, typical PI), for 15 STRs in Tijuana, Baja California. This Mexican border city was peculiar by the increase of African ancestry, and by presenting three STRs in Hardy–Weinberg disequilibrium, probably explained by recurrent gene flow. The Amerindian ancestry in Central and Southeast of Mexico was the greatest in Latin America (50.9–68.6%), only comparable with the North of Central America and Ecuador (48.8–56.4%), whereas the European ancestry was prevalent in South America (66.7–75%). The African ancestry in Mexico was the smallest (2.2–6.3%) in Latin America (≥2.6%), particularly regarding Brazil (21%), Honduras (62%), and the Caribbean (43.2–65.2%). CODIS-STRs allowed detecting significant population structure in Latin America based on greater presence of European, Amerindian, and African ancestries in Central/South America, Mexican Mestizos, and the Caribbean, respectively.

Solvable models for Kodaira surfaces Console, Sergio; Ovando, Gabriela Paola; Subils, Mauro In this work, we study families of compact spaces which are of the form G/Λk,iG/Λk,i for G the oscillator group and Λk,i

Morfosedimentología del fondo marino en el sector de entrada al estuario de Bahía blanca, Argentina.; Seafloor Morphosedimentology in the Entrance Sector of Bahía Blanca Estuary, Argentina Aliotta, Salvador; Spagnuolo, Jorge Osvaldo; Ginsberg, Silvia Susana; Minor Salvatierra, Marta Elizabeth En el amplio sistema estuarial de Bahia Blanca (provincia de Buenos Aires) existen sectores carentes de un conocimiento integral de las características morfosedimentológicas submarinas. Dentro de este contexto, en el presente trabajo se estudia el fondo marino a lo largo de la costa norte ubicada en el sector de entrada del Canal Principal del estuario de Bahía Blanca. Se realizaron relevamientos acústicos (ecosonda y sonar lateral) y muestreos de sedimentos de la superficie del fondo. Se determinó la presencia de geoformas depositacionales y erosivas. Entre las de carácter acrecional se han establecido diferentes tipos de dunas y lineaciones arenosas (sand ribbons). Entre los rasgos generados por erosión se encuentran escarpas, relativamente continuas e irregulares y afloramientos rocosos aislados. Asimismo, también se diferencian fondos de sedimentos cohesivos, tanto masivos como estratificados. Como formas antrópicas se distinguen surcos de dragado y la presencia de cañerías de oleoductos y restos metálicos. El análisis de las geoformas y los sedimentos permitió establecer que en el sector este de la franja costera estudiada, prevalece un transporte sedimentario como carga de fondo hacia la Plataforma Continental, mientras que en aguas someras del sector oeste, existe una marcada deriva de sedimentos hacia el interior del estuario. La conjunción de datos morfológicos y sedimentológicos posibilitó ampliar la caracterización de dos paleoniveles costeros, indicativos de períodos de estabilización del nivel del mar durante el último proceso transgresivo.; In the large Bahia Blanca estuarine system (province of Buenos Aires) there are sectors without a comprehensive assessment of submarine morpho-sedimentological features. Within this context, in this paper the seabed along the north coast of the entrance to the Principal channel of the estuary is studied. Acoustic surveys (echo sounder and side scan sonar) and sediments sampling were performed. The presence of depositional and erosional geoforms was determined. Among those of accretional nature have been established different types of dunes and sand ribbons. The erosive forms are scarps, relatively continuous and irregular, and rocky isolated outcrops. Also, seabed cohesive sediments, both massive and stratified, were differentiated. As anthropogenic forms furrows dredging and the presence of pipes for oil and metal debris were distinguished. The analysis of geoforms and sediments determined that in the east sector of the coastal strip studied prevails sediment transport as bedload towards the Continental Shelf, while in shallow waters of the western sector, there is a marked litoral drift towards the inside of estuary. The conjunction of morphological and sedimentological data allowed to extend the characterization of two ancient coastal levels, indicative of stabilization periods of sea level during the last transgressive process.

Persistent effect of organic matter pulse on a sandy soil of semiarid Patagonia Gonzalez Polo, Marina; Kowaljow, Esteban; Castán, Elisa; Sauzet, Ophelie; Mazzarino, Maria Julia Studies of degraded semiarid regions have shown that organic residue addition is a sound restoration alternative. We examined the effects of a single dose (40 Mg ha−1) of biosolids compost (BC) and compost of the organic fraction of municipal solid waste (MC) 6 years after they were applied to a sandy soil of NW Patagonia. Results were compared with those of inorganic fertilization (IF, 100 kg N + 35 kg P ha−1) treatment and of unamended control. We measured plant cover, biomass, and diversity and chemical, biological, and biochemical soil properties. We did not find any significant effect of treatments on plant attributes. However, effects on soil properties were significant and more persistent with composts than with IF, especially with BC, which had higher organic C and nutrients than MC. Total soil C and N were twice as high in the BC-amended soil as in the control and IF soils. Soil extractable P was 4-fold and 2-fold higher in BC- and MC-treated soils, respectively, than in the control soil, and even higher than in the IF treatment in response to BC. The highest β-glucosidase and acid phosphomonoesterase activities were found in the BC-treated soil, related to higher C and P in the soil and to higher activities of both enzymes in the biosolids compost. The highest phenol oxidase activity was found in MC and in the MC-treated soil. Potential respiration and K2SO4-extractable C were higher in the compost-treated soil, but there was no difference in microbial biomass C between the compost-treated and the control soils. Despite the fact that the soil was coarse textured and a single moderate dose of compost was applied, recovery of soil chemical, microbiological, and biochemical properties was long-lasting, indicating that application of urban compost is a feasible restoration practice in this semiarid region.

Ag nanoparticles formed by femtosecond pulse laser ablation in water: self assembled fractal structures Santillán, Jesica María José; Fernandez Van Raap, Marcela Beatriz; Mendoza Zélis, Pedro; Coral, Diego Fernando; Muraca, Diego; Schinca, Daniel Carlos; Scaffardi, Lucia Beatriz We report for the first time on the formation of self-assembled fractals of spherical Ag nanoparticles (Nps) fabricated by femtosecond pulse laser ablation of a solid silver target in water. Fractal structures grew both in two and three Euclidean dimensions (d). Ramified-fractal assemblies of 2 nm height and 5–14 μm large, decorated with Ag Nps of 3 nm size, were obtained in a 2d geometry when highly diluted drops of colloidal suspension were dried at a fast heating rate over a mica substrate. When less-diluted drops were dried at slow heating rate, isolated single Nps or rosette-like structures were formed. Fractal aggregates about 31 nm size in 3d geometry were observed in the as-prepared colloidal suspension. Electron diffraction and optical extinction spectroscopy (OES) analyses performed on the samples confirmed the presence of Ag and Ag2O. The analysis of the optical extinction spectrum, using the electrostatic approximation of Mie theory for small spheres, showed the existence of Ag bare core, Ag–Ag2O and air–Ag core–shell Nps, Ag–Ag2O being the most frequent type [69 % relative abundance (r.a.)]. Core-size and shell-thickness distribution was derived from OES. In situ scattering measurements of the Ag colloidal suspension, carried out by small-angle X-ray scattering, indicate a mass fractal composed of packaged 〈DSAXS〉 = (5 ± 1) nm particles and fractal dimension df = 2.5. Ex situ atomic force microscopy imaging displayed well-ramified structures, which, analyzed with box-counting method, yield a fractal dimension df = 1.67. The growing behavior of these 2d and 3d self-assembled fractals is consistent with the diffusion-limited aggregation model.

Evaluation of the antibacterial effects of vancomycin hydrochloride released from agar-gelatin-bioactive glass composites Rivadeneira, Josefina; Di Virgilio, Ana Laura; Audisio, Marcela Carina; Boccaccini, Aldo R.; Gorustovich Alonso, Alejandro Adrian The aim of this work was to evaluate the perfomance of agar-gelatin (AG) composites and AG-containing 45S5 bioactive glass (BG) microparticles (AGBG) in relation to their water uptake capacity, sustained release of a drug over time, and antibacterial effects. The composites were fabricated by the gel-casting method. To impart the local drug release capacity, vancomycin hydrochloride (VC) was loaded in the composites in concentrations of 0.5 and 1 mg ml(-1). VC release was assessed in distilled water at 37 °C up to 72 h and quantified spectrophotometrically. The antibacterial activity of composites was evaluated by the inhibition zone test and the plate count method. The experiments were performed in vitro up to 48 h on three staphylococcus strains: Staphylococcus aureus ATCC29213, S. aureus ATCC6538 and Staphylococcus epidermidis ATCC12228. The results showed that the addition of BG to AG composites did not affect the degree of water uptake. The release of VC was significantly affected by the presence of BG. VC release was higher from AGBGVC films than from AGVC ones over prolonged incubation times. Bacterial inhibition zones were found around the composites. The halos were larger when the cells were put in contact with AGVC composites than when they were put in contact with AGBGVC ones. Nevertheless, the viable count method demonstrated that the composites inhibited Staphylococcus cell growth with no statistical differences. In conclusion, the addition of BG did not reflect an improvement in the parameters studied. On the other hand, composites loaded with VC would have a role in prophylaxis against bacterial infection.

Iron-alumina synergy in the heterogeneous Fenton-type peroxidation of phenol solutions Di Luca, Carla; Ivorra, Fernando Daniel; Massa, Paola Andrea; Fenoglio, Rosa Juana Highly dispersed Fe2O3/Al2O3 catalysts (0.5–4 wt% Fe) were prepared by incipient wetness impregnation of iron citrate over a mesoporous alumina host. Their structural and textural properties were determined by N2 adsorption–desorption at −196 °C, XRD, TEM, SEM–EDAX, Raman and XPS. The structure of the catalytic materials resulted similar to the γ-Al2O3 support, exhibiting high dispersion levels of the iron oxide active phase with a narrow pore size distribution in the range of 2–7 nm and high surface areas. The capability of these systems as efficient and active Fenton-like catalysts, were further tested for the catalytic oxidation of concentrated phenol solutions (5 g/L) with H2O2 at 70 °C in a batch reactor. The effects of iron concentration, catalyst concentration and the nature of the support were evaluated, under adjusted sub-stoichiometric oxidant concentration. Besides the positive impact of increasing the iron loading, a synergistic effect between Fe and Al species would be possibly responsible of the improvements observed using higher iron dispersions and/or support concentrations. The catalytic performance of these alumina-based catalysts resulted very promissory as they yielded: total phenol abatement, high mineralization levels (up to a maximum of 80%) and high oxidant consumption efficiencies (between 80% and 96%).

El papel de los ancestros en la estructuración del espacio en las Quebradas Intermedias de Antofagasta de la Sierra, Catamarca González Baroni, Lucia Guadalupe; Babot, Maria del Pilar Se presenta y discute el papel de los ancestros en la estructuración del espacio en asentamientos agropastoriles del primer milenio DC de la cuenca de Antofagasta de la Sierra (Puna Meridional, Catamarca) a partir de nueva información procedente del sitio Punta de la Peña 9 (PP9). Se realiza un estudio de las correspondencias arquitectónicas y espaciales de recintos, con el propósito de definir vinculaciones entre los ámbitos funerarios y domésticos estudiados, a través de su caracterización arquitectónica, espacial, estratigráfica, cronológica y de asociaciones y contextos. En base a los resultados de la ampliación de excavaciones en el sector I del sitio PP9 se plantea que al menos, parte del patrón de asentamiento no corresponde al patrón de recintos aislados que se había descripto hasta el momento sino, más bien, a un conjunto arquitectónico en el cual se llevaron a cabo prácticas funerarias y domésticas dentro de un espacio compartido. De acuerdo a las dataciones obtenidas, el momento correspondiente a ca. 1500 - 1000 AP los recintos EF4, EF1, E3 y E5 tendrían un uso contemporáneo y estarían estructurando el espacio de la “aldea” o “poblado” como un lugar de actividades múltiples y de veneración de los ancestros, de manera similar a lo registrado en los valles semiáridos orientales. Es decir, que estos ámbitos funcionarían como lugares de memoria donde se mantuvo una relación en el tiempo entre los espacios conmemorados y los individuos que los conmemoraban. En este sentido, tanto la elección del lugar donde emplazar las tumbas y los recintos domésticos, como su construcción, son el resultado de acciones sociales y simbólicas. Asimismo, de acuerdo a la cronología abordada, esta manera de estructurar el espacio tendría un correlato con la intensificación de los procesos socioeconómicos agropastoriles.

Facies litológicas de la Formación Ventana en el extremo sur del cordón Rivadavia, Cordillera Principal, provincia de Chubut Litvak, Vanesa Dafne; Fernández Paz, Lucía; Iannelli, Sofía; Echaurren Gonzalez, Andres; Ibarra, Federico; Folguera Telichevsky, Andres Las facies litológicas de la Formación Ventana identificadas en el cordón Rivadavia se correlacionan con las rocas más septentrionales de la formación, localizadas en el extremo norte de la faja Andina dado que aquí predominan las facies volcánicas de composición basáltica a andesítica, como es típico de esta unidad. Las intercalaciones de tobas son subordinadas, tal como aparecen también en el Cerro Ventana. Esta correlación preliminar, basada especialmente en características estratigráficas y petrográficas, permite asignar las secuencias aquí estudiadas a la Formación Ventana, la cual representaría el volcanismo de arco recién iniciado para el Oligoceno superior-Mioceno inferior a estas latitudes en los Andes Nordpatagónicos.

Status of the World’s Soil Resources Technical Summary Alavipanah, Seyed Kazem; Alegre, Julio; AlShankiti, Abdullah; Arrouays, Dominique; Aulakh, Milkha Singh; Badraoui, Mohamed; Baptista, Isaurinda; Black, Helaina; Arbestain, Marta Camps; Chude, Victor; El Sheikh, Elsiddig A. E.; Espinosa Victoria, David; Hempel, Jon; Henriquez, Carlos Roberto; Hong, Suk Young; Krasilnikov, Pavel; Mamo, Tekalign; Mendonça Santos, Maria de Lourdes; Sobocká, Jaroslava; Taboada, Miguel Angel; Vijarnsorn, Pisoot; Yagi, Kazuyuki; Yemefack, Martin; Zhang, Gan Lin This document presents the first major global assessment ever on soils andrelated issues.Why was such an assessment not carried out before? We have taken soils for granted for a long time. Nevertheless, soils are the foundation of food production and food security, supplying plants with nutrients, water, and support for their roots. Soils function as Earth´s largest water filter and storage tank; they contain more carbon than all above-ground vegetation, hence regulating emissions of carbon dioxide and other greenhouse gases; and they host a tremendous diversity of organisms of key importance to ecosystem processes.However, we have been witnessing a reversal in attitudes, especially in light ofserious concerns expressed by soil practitioners in all regions about the severethreats to this natural resource. In this more auspicious context, when theinternational community is fully recognizing the need for concerted action , theIntergovernmental Technical Panel on Soils (ITPS), the main scientific advisorybody to the Global Soil Partnership (GSP) hosted by the Food and AgricultureOrganization of the United Nations (FAO), took the initiative to prepare thismuch needed assessment.The issuance of this first Status of the World?s Soil Resources report was most appropriately timed with the occasion of the International Year of Soils (2015) declared by the General Assembly of the United Nations. It was made possible by the commitment and contributions of hosts of reputed soil scientists and their institutions. Our gratitude goes to the Lead Authors, Contributing Authors, Editors and Reviewers who have participated in this effort, and in particular to the Chairperson of the ITPS, for his dedicated guidance and close follow up. Many governments have supported the participation of their resident scientists in the process and contributed resources, thus also assuring the participation of experts from developing countries and countries with economies in transition. In addition, a Technical Summary was acknowledged by representatives of governments assembled in the Plenary Assembly of the GSP, signaling their appreciation of the many potential uses of the underlying report. Even more comprehensive and inclusive arrangements will be sought in the preparations of further, updated versions.

Regulación del desarrollo de la glándula mamaria bovina: efecto de parasitosis gastrointestinales en terneras Holstein Bonadeo, Nadia; Perri, Adrián Francisco; Mejia, M.; Licoff, N.; Becu, Damasia; Cristina, Silvia Carolina; Lacau, Isabel María Los parásitos gastrointestinales afectan el desarrollo de terneras Holstein y disminuyen el IGF-1 circulante. Para estudiar la posible alteración del desarrollo de la glándula mamaria y de su regulación, se asignaron alternativamente al nacer, 40 terneras del tambo de la Escuela Inchausti (UNLP) a dos grupos de tratamiento.

Acciones urbanas: Construcción colectiva del espacio público Stang, José Ignacio El presente trabajo apunta en primera instancia a analizar y reflexionar nuestras ciudades desde la perspectiva de la crisis actual. Luego desde esta mirada y en la búsqueda de caminos posibles para intervenir en ellas, el foco se centrará en las denominadas Acciones Urbanas y como a partir de estas se abre la posibilidad de manifestar, intervenir y modificar patrones de comportamiento en los espacios públicos apuntando a una construcción colectiva de ellos. Debido a la acotación de esta investigación, se pondrán a luz solo tres Acciones Urbanas realizadas en distintos escenarios. Se seleccionarán de acuerdo a su escala de intervención, el tejido de inserción, los actores implicados, el contexto urbano y social, y su repercusión.Metodológicamente y debido a limitaciones objetivas se desarrollará en dos momentos. Uno primero que parte de la preocupación temática descripta y en base a la cual se realizará una reflexión inicial. Desde el área problemática descripta se llegará un reconocimiento de la situación. En base a esta exploración y descripción, se formulará que posibilidad de cambio o mejora existe para tal situación. En el segundo momento se reflexionará sobre la posible estrategia, desde el estudio de casos, a utilizar para transformar la situación-problema; estrategia que apunta a generar el cambio o la mejora que se busca. Así se integrará la preocupación temática junto con las posibilidades y limitaciones objetivas que se observan en la realidad.

El caso Píparo: muerte, conmoción y cambio Kessler, Gabriel; Galar, Santiago El argumento que sostenemos, en línea con lo sostenido por Carolina Schillagi en su artículo, es que la conmoción pública suscitada por determinadas muertes abre un período de posibilidad para la producción de cambios. Pero para que se realicen transformaciones es preciso un actor o una coalición con poder suficiente para impulsar las medidas. Sin embargo se trata de una condición necesaria pero no suficiente: la solución propuesta debe ser acertada en al menos dos sentidos. En primer lugar, siguiendo la concepción de problemas públicos de J. Gusfield (2014), el propietario político interpelado debe elegir a un responsable de la solución que acepte realizarlas (pudiendo ser él mismo u otro). Es preciso en segundo lugar evitar escollos: la definición del problema, las soluciones propuestas y sus responsables no deben dar lugar a controversias de tal magnitud que otros actores movilicen sus recursos para impedirlos, al considerarlos en franca oposición a sus valores o intereses. Intentaremos asimismo alegar que la conmoción por la muerte de Isidro no debe ser considerada en forma aislada, sino como el punto más crítico de una trama dramática, cuyo efecto fue acelerar los tiempos al reforzar el llamamiento a cambios urgentes. Pero a diferencia de otros hechos luctuosos, seguidos de renovados clamores por más policías y leyes más duras, las expresiones públicas que suscitó su muerte franquearon el camino para que, lejos del debate público, se promulgaran medidas más bien técnicas y ceñidas a la seguridad bancaria. En tal sentido, el caso Píparo revela una diferenciación entre la “inseguridad” como problema público marco, ya establecido al menos una década antes del hecho, y la paulatina configuración de una serie de problemas públicos específicos dentro de dicho marco, tales como secuestros extorsivos, "entraderas" o robos de autos alrededor de los cuales comienzan a generarse dinámicas propias de expertos, voceros y, en este caso, de posibles soluciones.

Dialéctica im-posible, lenguaje y redención: la teología poética de Franz Rosenzweig Taub, Emmanuel Habitamos el desmoronamiento de la historia, o una historia de la destrucción de la historia. Las instituciones del hombre no buscan detener el tiempo, sino amortiguarlo: acompañar el tiempo escondiendo la catástrofe de la historia, la caída de las propias instituciones en los confines del tiempo y sus des-usos. Lo que se encuentra en juego no es el mundo-naturaleza que ha estado ahí y no importa si estará porque en definitiva ese saber no es problema del hombre, sino el hombre. Y si la tarea es encontrar las hendiduras, el camino será a través del lenguaje: primera y última relación del hombre con lo divino, y por ello mismo, con el mesianismo siempre por llegar. De esta manera, este texto analiza los avatares estéticos que desarrolla Franz Rosenzweig en su obra buscando desde ahí construir la idea de una teología poética.

La antropología del De opificio hominis de Gregorio de Nisa en la obra de Nicolás de Cusa Bastitta Harriet, Francisco El tratado De opificio hominis de Gregorio de Nisa fue una de las únicas obras antropológicas traducidas del griego al latín en los albores de la Edad Media, por Dionisio el Exiguo entre fines del siglo V y principios del siglo VI y por Juan Escoto Eriúgena en el siglo IX. Nicolás de Cusa conoció ciertamente la obra de modo indirecto, a través de las extensas citaciones presentes en los libros II y IV del Periphyseon eriugeniano y a través de su reproducción parcial en la Clavis physicae de Honorius Augustodunensis. Nuestro trabajo analizará estas y otras posibles vías de recepción tanto directas como indirectas del texto de Gregorio por parte del Cusano, así como la influencia filosófica de algunos temas propios de la antropología nisena en su pensamiento, como la concepción de la imago Dei, de su carácter viviente y de su simplicidad, la incomprehensibilidad del intelecto o la mente (noûs) humana y las teorías acerca del libre albedrío humano y del hombre como microcosmos.