Conservation of migratory Magellanic penguins requires marine zoning Stokes, David L.; Boersma, P. Dee; Lopez de Casenave, Javier Nestor; Garcia Borboroglu, Jorge Pablo Conservation of migratory species requires an understanding of their migration path and pattern. We used band returns and satellite tracking to characterize the seasonal migration of Magellanic penguins breeding in southern Argentina, with the purpose of identifying an effective conservation approach for this species. Band returns show these penguins migrate annually to the coastal waters of northern Argentina, Uruguay, and southern Brazil, an average one-way distance of approximately 2000 km, and a modal distance of 2300–2400 km. Satellite data indicate that the penguins follow a migration corridor within 250 km of shore. Mean migration distance varied among years. Juveniles migrated farther on average than older birds, although migration distance of different age classes overlapped substantially. Mortality rates during migration were higher among younger birds, and juvenile mortality rate during migration was inversely correlated with cohort survival, indicating that mortality during migration is an important determinant of population recruitment. A minimum of 13% of the migration-period mortality we recorded resulted from fisheries bycatch and oil pollution. Because of the penguin’s mode of travel (swimming at or near the surface), the large spatial extent of its migration, and the intensity of human use of the area, effective conservation through conventional coastal marine reserves is unlikely. Marine zoning is an alternative that could provide the spatial scale and flexibility necessary to accommodate both penguin migration and human activities. As the waters traversed by Magellanic penguins are among the most threatened in Latin America, zoning for protection of this wide-ranging and charismatic species can also protect regional biodiversity.

Leuconostoc bacteriophages from blue cheese manufacture: long-term survival, resistance to thermal treatments, high pressure homogenization and chemical biocides of industrial application Pujato, Silvina; Guglielmotti, Daniela Marta; Ackerman, Hans W.; Patrignani, Francesca; Lanciotti, Rosalba; Reinheimer, Jorge Alberto; Quiberoni, Andrea del Lujan Nine Leuconostoc mesenteroides phages were isolated during blue cheese manufacture yielding faulty products with reduced eye formation. Their morphologies, restriction profiles, host ranges and long-term survival rates (25ºC, 8ºC, -20ºC and -80ºC) were analyzed. Based on restriction analysis, six of them were further examined regarding resistance to physical (heat and high pressure homogenization, HPH) and chemical treatments (ethanol, sodium hypochlorite, peracetic acid, biocides A, C, E and F). According to their morphology, Ln. mesenteroides phages studied in the present work belonged to Caudovirales order and Siphoviridae family. Six distinct restriction patterns were obtained with EcoRV, HindIII, ClaI and XhoI enzymes, revealing interesting phage diversity in the dairy environment. No significant reductions in phage counts were observed after ten months of storage at -20ºC and -80ºC, while slightly and moderate decrease in phage numbers were noticed at 8ºC and 25ºC, respectively. Phages subjected to heat treatments generally showed high resistance at 63ºC and moderate resistance at 72ºC. However, 80ºC for 30 min and 90ºC for 2 min led to complete inactivation of viral particles. In general, the best ethanol concentration tested was 75%, as complete inactivation for most Leuconostoc phages within 30 min of incubation was achieved. Peracetic acid, biocides A, C, E and F were highly effective when used at the same or at a moderately lower concentration as recommended by the producer. Usually, moderate or high concentrations (600-1600 ppm) of sodium hypochlorite were necessary to completely inactivate phage particles. Leuconostoc phages were partially inactivated by HPH treatments as remaining viral particles were found even after 8 passes at 100 MPa. This is the first report of Ln. mesenteroides phages isolated from an Argentinean dairy cheese plant. Results of this work could be useful for establishing the most effective physical and chemical treatments for inactivating phages in industrial plants and laboratory environments

Utilización de la espectroscopía de fluorescencia para la evaluación de la estabilidad oxidativa de carne bovina en almacenamiento. Pouzo, Laura Beatriz; Rossetti, Luciana; Descalzo, Adriana Maria; Pavan, Enrique Se definieron cuatro tratamientos dietarios en base al tipo de suplemento ofrecido a novillos en pastoreo: CNTRL (sin suplemento); LINO-0 (Maíz, tradicional); LINO-1 (Maíz + 1 nivel de lino); LINO-2 (Maiz + 2 niveles de lino). Las condiciones de almacenamiento fueron: al vacío (EV; 3, 14 y 56 días) y exposición en bandeja (EA; 0 y 5 días). Fueron detectados diferentes compuestos fluorósforos en carne: residuos de triptófano, compuestos de oxidación y porfirinas. El triptófano se incremento a los 56 d de EV, pero tendió a disminuir a los cinco días de EA; las porfirinas incrementaron gradualmente durante el EV de la carne pero disminuyeron durante la EA, los productos de oxidación incrementaron en ambos almacenamientos. Este estudio reveló el potencial de la señales de fluorescencia para detectar cambios oxidativos en carne almacenada con un método rápido y no destructivo.

Critical size defect regeneration by rhPTH collagen membrane as a new tissue engineering tool Missana, Liliana Raquel; Jammal, María Victoria Recombinant Human Parathyroid Hormone (rhPTH 1-34) administration is an effective treatment to improve bone mass in osteoporosis. The aim of this study was to develop a Tissue Engeenering Tool for bone regeneration. We evaluated the efficacy of a freeze dried rhPTH membrane in calvarial critical size defect (CZD). 44 Wistar female rats (body weight 150 ± 50 g) with CZD (5mm) were divided into 4 groups: group 1: rhPTH membrane (rhPTHm); group 2: atelocollagen membrane (Cm); group 3: rhPTH and atelocollagen I (CrhPTHm); group 4: without any treatment (CG). All samples were evaluated on the 1st, 3rd and 6th weeks (wks) post-surgery by soft X-ray, histological and histometric studies. Soft X-ray results showed a radiolucent image with many irregular radiopaque areas. Histologically, rhPTHm was replaced by reticular bone (7%) since 3rd wk, and lamellar bone ossicles (30%) at 6th wk. Cm showed bone formation like composite bone type on wk 1st, 3rd and 6th (2%, 44% and 41% respectively). With CrhPTHm, bone formation was observed in all periods (2.4%, 48% and 53%), showing statistical difference with CG in the 3rd and 6th wks (p= 0.03 and 0.01). Our results demonstrated the effectiveness of a new biomaterial called CrhPTHm because its ability to regenerate calvarial CZD. Moreover, the membrane represents a new local intermittent delivery system allowing rhPTH slow release.

Do aquatic plant assemblages in the Paraná River change along the river's length? Neiff, Juan Jose; Casco, Sylvina Lorena; Mari, Eliana Karina Alejandra; Di Rienzo, Julio Alejandro; Poi, Alicia Susana G. We studied the distribution pattern of aquatic plants along the Paraná River from its confluence with the Iguazú River to the Delta (2366. km). At three representative locations, Upper Paraná, Lower Paraná, with Paraná-Paraguay confluence and Paraná-Santa Fe section and, Delta, data were collected during extreme low waters (limnophase) and high waters (potamophase). Species richness and abundance at 325 sites were analyzed for both periods using β diversity and the Indicator Species Analysis (ISA). To evaluate the importance of species-hydrological-phase combinations, linear discriminant analysis was applied. We compared hydrological time series at the same sites using PULSE software. Although there are differences in species richness along the river, we found no clear longitudinal pattern in the distribution and diversity of vegetation along the course of the river. From a total of 62 species for the entire study area, the ISA separated 17 indicator species. There are indicator species in each section and hydrological phase, although 29% of the total was recorded in all river sections. Estimates of β diversity (spatial turnover of species) among the river sections was higher during low water (β= 16%) than during high water (β= 11%) and varied between 12 and 58% among plots depending on the hydrological phase. Results of this study will contribute to incorporate spatial variation into pulse regime theories of large floodplain rivers. © 2014 Elsevier B.V.

Composition of the diet of Netta peposaca (Birds: Anseriformes) in Santa Fe province, Argentina Olguin, Pamela Fernanda; Attademo, Andres Maximiliano; Beltzer, Adolfo Hector; Ronchi Virgolini, Ana Laura; Lorenzón, Rodrigo Ezequiel; Caselli, Elsa Andrea; Arce, Sofía Irene; Percara, Alejandro Rubén César We examined the diet of the Rosy-billed Pochard, Netta peposaca (Vieillot, 1816), (n = 59) during the autumn of 2010 in Santa Fe province, Argentina. Were analyzed a total of 59 ducks (n = 37 females and n = 22 males) to assess their gastrointestinal contents. The trophic spectrum was composed of 16 taxa (plant fraction: animal fraction 9 and 7). The contribution of each food category estimated using the IRI was: Echynochloa sp. (Poaceae) = 4301, Polygonum sp. (Polygonaceae) = 956, and unidentified graminoid species = 53 (females: Echynochloa sp. = 4313, Polygonum sp. = 1095 and males: Echynochloa sp. = 5522, Polygonum sp. = 814). No significant differences were found between females and males in diet composition (Fisher's test, p < 0.05). Moreover, the diversity index (H') was significantly (Mann-Whitney, p < 0.05) different between sexes. The Rosy-billed Pochard showed a predominantly phytophagous feeding habit in autumn. Likewise, this is the first contribution on the sexual differences in the feeding biology of the Rosy-billed Pochard.

Las (sin) razones del justo Grassi, Martín El presente trabajo es una meditación en torno a la relación entre la ética y el derecho, a partir de la imposibilidad de responder completamente por el otro que reclama nuestra atención y reconocimiento. Frente a una ética de la prudencia y del equilibrio, la ética atravesada por la idea del amor –como contrapunto dialéctico de la justicia– se constituye desde el desequilibrio y la desmesura correlativa a la infinita responsabilidad que tenemos por el otro. De allí que el justo actúa desde (sin)razones, en una tensión nunca resuelta entre las mediaciones jurídicas y la exigencia ética.

La democratización del bienestar en el peronismo (1945-1955): ¿ruptura o continuidad con el pasado?; Democratization of welfare during Peronism (1945-1955): Rupture or continuity with the past? Schteingart, Daniel Matías En este trabajo se procurará analizar en qué medida las dos primeras presidencias de Juan Perón implicaron una profundización de tendencias de movilidad social ascendente que ya habían existido anteriormente en la sociedad argentina, y en qué grado supusieron una real novedad con el pasado. Esto nos obligará a articular la investigación en torno de dos grandes ejes: en primer lugar, se estudiarán dichas rupturas y continuidades en el plano material -es decir, en lo que atañe a las condiciones objetivas de vida-, para luego complementar el análisis con lo ocurrido en la esfera simbólica -o sea, cómo la experiencia del peronismo alteró las subjetividades de las clases trabajadoras y de los sectores medios y cómo incidió en la constitución de una “memoria histórica” tras el derrocamiento de Perón en 1955-. La hipótesis central de este trabajo es que, en el plano material, el peronismo vino a acelerar y generalizar tendencias a la “democratización del bienestar” que, en algunos aspectos, ya habían existido en la sociedad argentina hasta por lo menos 1930 (por ejemplo, en lo que atañe al mejoramiento del poder adquisitivo de la población, o en lo que respecta a la vivienda, la educación y la salud) pero, a la vez, dicha profundización de las tendencias a la “democratización del bienestar” generó rupturas en el registro de lo simbólico, que dieron lugar a grandes conflictos.; The aim of this paper is to analyze to which point Juan Perón's two first presidencies implied a deepening in the trend of upward social mobility (which had already existed previously in Argentine society), and to which degree they imposed a real change in relation to the past. This will lead to an articulation of the investigation around two central concepts: firstly, there will be a study of said interruptions and continuities in the material realm - which is to say, that which regards objective life conditions- to later complement the analysis with the events that took place in the symbolical realm -that is, how the Peronist experience altered the subjetivities of the working classes and middle sectors and how it participated in the constitution of an "historical memory" after Perón's overthrow in 1955-. The central hypothesis of this paper is that, in the material realm, Peronism came to accelerate and generalize trends towards the "democratization of welfare" which, in some aspects, had been present in Argentine society up until at least 1930 (for example, as what concerns the improvement of the people's acquisitive power, or what concerns housing, education and healthcare) but, at the same time, said deepening of the trends towards "democratization of welfare" lead to interruptions in the record of the symbolical realm, which gave leeway to great conflict.

Las ciudades y sus muros de cristal: Ajuste neoliberal y lecciones de una experiencia en el noroeste argentino; The cities and their glass walls: Neoliberal adjustment in an experience in northwestern Argentina Bergesio, Liliana del Carmen; Golovanevsky, Laura Andrea En este artículo se discuten algunas consecuencias de las políticas neoliberales de la década de 1990 en Jujuy (Argentina), a partir del estudio de los cambios en el entramado urbano de su capital. Con el surgimiento y desarrollo explosivo del barrio Alto Comedero se observa cómo las políticas neoliberales profundizaron la separación entre sectores sociales, generando procesos de relegación de grupos desfavorecidos a zonas alejadas e invisibles de la ciudad, dejando marcas indelebles en el imaginario, las subjetividades y las condiciones materiales de vida de tales grupos.; In this article we discuss some consecquences of neoliberal policies in 1990’s decade in Jujuy (Argentina), based on the study of changes that took place in the urban scenery of its capital city. Throughout the emergence and explosive development of a local district called Alto Comedero we observe how neoliberal policies deepened the division between social groups and relegating those less wealthy to remote and invisible parts of the city, leaving indelible marks on the imaginary, the subjectivities and the material life conditions of such groups.

Espacios sagrados en el mundo andino. Excavación de una huanca en Las Pailas (Cachi, Salta, Argentina) Paez, Maria Cecilia; Lynch, Virginia; Besa, Yamila En el mundo andino prehispánico, el estudio de las prácticas agrícolas requiere abordar el universo social y simbólico que constituye la matriz de significado,considerando que el espacio natural y social no son elementos indisociados dentro de la cosmovisión de los grupos. En este marco, nos proponemos analizar el registro material vinculado a las prácticas rituales en el sitio arqueológico de Las Pailas (Cachi, Salta). Para ello se excavó una estructura con singularidades arquitectónicas cuyo registro artefactual indicaría que allí se habrían desarrollado actividades de carácter festivo-ritual.

How Can Network-Pharmacology Contribute to Antiepileptic Drug Development? Di Ianni, Mauricio Emiliano; Talevi, Alan Network-pharmacology is a field of pharmacology emerging from the observation that most clinical drugs have multiple targets, contrasting with the previously dominant magic bullet paradigm which proposed the search of exquisitely selective drugs. What is more, drug targets are often involved in multiple diseases and frequently present co-expression patterns. Therefore, useful therapeutic information can be drawn from network representations of drug targets. Here, we discuss potential applications of drug-target networks in the field of antiepileptic drug development.

Canales aéreos y subterráneos de Las Pailas (Cachi - Salta) aproximaciones al estudio de la red hidráulica Paez, Maria Cecilia; Giovannetti, Marco Antonio La gestión del agua necesaria para los cultivos ha sido una preocupación constante en el análisis de las prácticas agrícolas campesinas andinas. Desde los momentos prehispánicos a la actualidad, el riego ha tenido un protagonismo clave en el conjunto de la vida comunal, sujeto a las reglas que gobiernan la vida social y cultural de las comunidades. Es por ello que su desarrollo no solo involucró un conjunto de características técnicas y conocimientos adquiridos, sino también una dimensión simbólico religiosa como complemento de la dimensión empírica (Van Kessel y Condori Cruz 1992). En este marco, el análisis de las variables sociales y simbólicas se muestra como un complemento obligado en el análisis de la dinámica productiva andina, acompañando los aspectos meramente técnicos vinculados a la ingeniería hidráulica. Este artículo discurre en este sentido, en consonancia con las investigaciones que venimos desarrollando en el Valle Calchaquí Norte. Para ello aquí esbozaremos los resultados de los estudios que venimos desarrollando sobre la tecnología de riego desarrollada en el sitio arqueológico Las Pailas, la que ha posibilitado y favorecido el desarrollo de una agricultura intensiva a lo largo de casi 1000 ha durante los momentos prehispánicos del desarrollo social local.; The great extension of cultivated land during prehispanic times in Las Pailas site and the technology deployed for this constitute a very distinctive aspect of the site. Almost 700 ha of fields distributed in two sectors, Las Pailas 1 and Las Pailas 2, were watered by an extensive network of canals leading water from the rivers of snowmelt and springs in the hills. Various types of air channels of simple technology, dug into the ground, uncoated are combined with complex stone-lined underground channels which required an advanced hydraulic knowledge. This paper presents the first results about the description of both morphological types, their spatial distribution and possible coordination within a network that would have allowed the artificial irrigation of cropland. We also discuss some chronological parameters about the Late and Inca periods in the region.

Protein intrinsic disorder and network connectivity. The case of 14-3-3 proteins Uhart, Marina; Bustos, Diego Martin The understanding of networks is a common goal of an unprecedented array of traditional disciplines. One of the protein network properties most influenced by the structural contents of its nodes is the inter-connectivity. Recent studies in which structural information was included into the topological analysis of protein networks revealed that the content of intrinsic disorder in the nodes could modulate the network topology, rewire networks, and change their inter-connectivity, which is defined by its clustering coefficient. Here, we review the role of intrinsic disorder present in the partners of the highly conserved 14-3-3 protein family on its interaction networks. The 14-3-3s are phospho-serine/threonine binding proteins that have strong influence in the regulation of metabolism and signal transduction networks. Intrinsic disorder increases the clustering coefficients, namely the inter-connectivity of the nodes within each 14-3-3 paralog networks. We also review two new ideas to measure intrinsic disorder independently of the primary sequence of proteins, a thermodynamic model and a method that uses protein structures and their solvent environment. This new methods could be useful to explain unsolved questions about versatility and fixation of intrinsic disorder through evolution. The relation between the intrinsic disorder and network topologies could be an interesting model to investigate new implicitness of the graph theory into biology.

Entomofauna acuática del Parque Nacional Natural Gorgona,Pacífico colombiano, con énfasis en Ephemeroptera y Plecoptera; Aquatic entomofauna from Gorgona National Natural Park, Colombian Pacific, with emphasis in Ephemeroptera and Plecoptera Zuñiga, Maria del Carmen; Cardona, William; Molineri, Carlos; Mendivil, Julián; Cultid, Carlos; Chara, Ana Marcela; Giraldo, Alan Este trabajo constituye la primera aproximación al conocimiento de las especies que caracterizan la entomofauna acuática del PNN Gorgona, con énfasis en Ephemeroptera y Plecoptera, su distribución, ecología y relación con la parte continental. Entre Octubre de 2010 y Junio de 2011 se realizaron recolectas de estados inmaduros y adultos en cinco quebradas del sector oriental de la isla, con ayuda de redes entomológicas, trampas Malaise y de luz blanca y negra. Se registran nueve órdenes, 28 familias, 39 géneros y 16 especies. Por primera vez se reportan la familia Dytiscidae (Coleoptera) y los géneros: Zelusia, Farrodes y Terpides (Ephemeroptera), Leucotrichia y Wormaldia (Trichoptera), Laccodytes, Neoelmis y Pheneps (Coleoptera), Maruina y Limonia (Diptera). Se encontraron cuatro especies nuevas de Ephemeroptera y cuatro de Plecoptera, en proceso de descripción. Además, Leptohyphes jodiannae, L. maculatus y Hagenulopsis esmeralda son primeras citas para Colombia. Farrodes caribbianus, F. roundsi, Hagenulopsis zunigae, Zelusia principalis y Anacroneuria choco, reportadas para el país, amplían su rango de distribución para el PNN Gorgona. La riqueza de familias, géneros y especies es alta y se considera una extensión de la fauna de corrientes hídricas de bajo y mediano orden del trópico continental, particularmente en la provincia del Chocó biogeográfico.; Gorgona is a Colombian continental island that biogeographically belongs in the Choco region. This work constitutes a first approximation to the aquatic insects, with emphasis in Ephemeroptera and Plecoptera: distribution, ecology, and associations to the continental mainland. Between October 2010 and June 2011, immature and adult specimens were collected in five streams of the island´s Western sector using entomological nets, Malaise traps, and light traps. A total of nine orders, 28 families, 39 genera and 16 species of aquatic insects were found. New geographical records for Gorgona include: Dytiscidae (Coleoptera), Zelusia, Farrodes and Terpides (Ephemeroptera), Leucotrichia and Wormaldia (Trichoptera), Laccodytes, Neoelmis and Pheneps (Coleoptera), Maruina and Limonia (Diptera). As part of this study, four new species for each, Ephemeroptera and Plecoptera, were found. Leptohyphes jodiannae, L. maculatus and Hagenulopsis esmeralda are recorded for the first time for Colombia. Farrodes caribbianus, F. roundsi, Hagenulopsis zunigae, Zelusia principalis and Anacroneuria choco are reported for the first time for the National Park. The high abundance of families, genera, and species is similar to that of low order streams in the tropic mainland, particularly those associated to the Choco bio-geographical province.

The role of protein dynamics and thermal fluctuations in regulating cytochrome c/cytochrome c oxidase electron transfer Álvarez Paggi, Damián Jorge; Zitare, Ulises Alejandro; Murgida, Daniel Horacio In this overview we present recent combined electrochemical, spectroelectrochemical, spectroscopic and computational studies from our group on the electron transfer reactions of cytochrome c and of the primary electron acceptor of cytochrome c oxidase, the CuA site, in biomimetic complexes. Based on these results, we discuss how protein dynamics and thermal fluctuations may impact on protein ET reactions, comment on the possible physiological relevance of these results, and finally propose a regulatory mechanism that may operate in the Cyt/CcO electron transfer reaction in vivo. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference.

Synthesis, Characterization, and Catalytic Properties of Cationic Hydrogels Containing Copper(II) and Cobalt(II) Ions Lombardo Lupano, Lucía Victoria; Lazaro Martinez, Juan Manuel; Piehl, Lidia Leonor; Rubín de Celis, Emilio; Torres Sanchez, Rosa Maria; Campodallorto, Viviana Here, we report the synthesis and characterization of a hydrogel based on ethylene glicol diglycidyl ether (EGDE) and 1,8-diamino-3,6-dioxaoctane (DA). Chemically stable Co(II) and Cu(II) coordination complexes were prepared with this non-soluble polyelectrolyte, Poly(EGDE-DA), and studied by ss-NMR, FTIR, thermogravimetry and microscopy. Mesopores were found in all the samples, the thermal stability of the polymer matrix was highly affected by the presence of metal ions, and the 13C CP-MAS spectrum for the Cu(II)-complex evidenced a significant increase in the reticulation degree by Cu(II) ions. The catalytic activity of these materials on H2O2 activation was studied by Electron Spin Resonance (ESR). The Co(II)-Poly(EGDE-DA) / H2O2 heterogeneous system produced O2, anion superoxide (O2*¯) and hydroxyl radical (OH*), which diffused into the solution at the time that a decrease in pH was detected. In the same way, the Cu(II)-Poly(EGDE-DA) / H2O2 heterogeneous system produced O2 and OH*. H2O2 activation by the Poly(EGDE-DA) complexes with Co(II) and Cu(II) was applied on the decolorization of solutions of the azo-dye Methyl Orange (MO). In the presence of 63 mM H2O2, 87 % of MO was removed in 10 min with Cu(II)-Poly(EGDE-DA) and in 110 min with Co(II)-Poly(EGDE-DA). In addition, the pharmaceutical product epinephrine was partially oxidized to adrenochrome by the O2*¯ released from the Co(II)-Poly(EGDE-DA) / H2O2 heterogeneous system.

Discontinuous bifurcation analysis of thermodynamically consistent gradient poroplastic materials Mroginski, Javier Luis; Etse, Jose Guillermo In this work, analytical and numerical solutions of the condition for discontinuous bifurcation of thermodynamically consistent gradient-based poroplastic materials are obtained and evaluated. The main aim is the analysis of the potentials for localized failure modes in the form of discontinuous bifurcation in partially saturated gradient-based poroplastic materials as well as the dependence of these potentials on the current hydraulic and stress conditions. Also the main differences with the localization conditions of the related local theory for poroplastic materials are evaluated to perfectly understand the regularization capabilities of the non-local gradient-based one. Firstly, the condition for discontinuous bifurcation is formulated from wave propagation analyses in poroplastic media. The material formulation employed in this work for the spectral properties evaluation of the discontinuous bifurcation condition is the thermodynamically consistent, gradient-based modified Cam Clay model for partially saturated porous media previously proposed by the authors. The main and novel feature of this constitutive theory is the inclusion of a gradient internal length of the porous phase which, together with the characteristic length of the solid skeleton, comprehensively defined the non-local characteristics of the represented porous material. After presenting the fundamental equations of the thermodynamically consistent gradient based poroplastic constitutive model, the analytical expressions of the critical hardening/softening modulus for discontinuous bifurcation under both drained and undrained conditions are obtained. As a particular case, the related local constitutive model is also evaluated from the discontinuous bifurcation condition stand point. Then, the localization analysis of the thermodynamically consistent non-local and local poroplastic Cam Clay theories is performed. The results demonstrate, on the one hand and related to the local poroplastic material, the decisive role of the pore pressure and of the volumetric non-associativity degree on the location of the transition point between ductile and brittle failure regimes in the stress space. On the other hand, the results demonstrate as well the regularization capabilities of the non-local gradientbased poroplastic theory, with exception of a particular stress condition which is also evaluated in this work. Finally, it is also shown that, due to dependence of the characteristic lengths for the pore and skeleton phases on the hydraulic and stress conditions, the non-local theory is able to reproduce the strong reduction of failure diffusion that takes place under both, low confinement and low pore pressure of partially saturated porous materials, without loosing, however, the ellipticity of the related differential equations.

Electric and magnetic field manipulation and storage of charge-tunable excitons Simonin, Jorge Marcos; Proetto, Cesar Ramon; Pacheco, Mónica; Barticevic, Z. The excitonic spectrum of radially polarized semiconductor rings has been analyzed theoretically, in the presence of an in-plane electric field and a perpendicular magnetic field. Based on the numerically exact solution, a regime has been found where the exciton behaves as a single carrier or quasiparticle, with an effective and tunable electric charge determined by the ring geometry. A protocol is proposed for the storage of excitons without destroying them, consisting in converting them from “bright” to “dark,” by performing a sequence of well-defined steps. Accurate analytical approximations are provided for each of the exciton regimens found: quasifree, locked, and broken.

Piptochaetium fuscum (Nees ex Steud.) Barkworth, Ciald., & Gandhi, a new combination replacing Piptochaetium setosum (Trin.) Arechav. Barkworth, Mary E.; Cialdella, Ana Maria; Gandhi, Kanchi A new name, Piptochaetium fuscum, is provided for a taxon hitherto known as Piptochaetium setosum (Trin.) Arechav. Morphological, anatomical, and molecular studies that argue against including Piptochaetium in Stipa, and hence use of S. purpurata (Phil.) Columbus & J.P. Sm., are cited.

Atomic entropy squeezing in three-level systems Reboiro, Marta; Civitarese, Enrique Osvaldo; Tielas, Diego Alejandro We consider the problem of an atomic three-level system (in a ladder configuration) interacting with a radiation field. Assuming a coherent state as the initial state, we solve exactly the time evolution of the system. We discuss the appearance of atomic squeezing and calculate the atomic spin squeezing and the atomic entropy squeezing. We show that both parameters predict similar angular and time dependences.