Contribution of macroporosity to water flux of a soil under different tillage systems; Contribuição da macroporosidade para o fluxo total de água em um solo sob diferentes sistemas de preparo Soracco, Carlos Germán; Lozano, Luis Alberto; Balbuena, Roberto Hernan; Ressia, Juan Manuel; Filgueira, Roberto Raul In view of the importance of the macroporosity for the water transport properties of soils, its quantitative assessment is a challenging task. Measurements of hydraulic conductivity (K) at different soil water tensions and the quantification of water-conducting macropores (..M)of a soil under different tillage systems could help understand the effects on the soil porous system and related hydraulic properties. The purpose of this study was to assess the effects of Conventional Tillage (CT), Chisel Plow (CP) and No Tillage (NT) on ..M and on K; and to quantify the contribution of macroporosity to total water flux in a loam soil. A Tension disc infiltrometer was used at two soil water pressure heads (-5 cm, and 0) to infer ..Mand K, during fallow. Macroporosity was determined based on the flow contribution between 0 and -5 cm water potentials (K0,K5, respectively), according to the Hagen- Poiseuille equation. The K0 values were statistically higher for CT than for NT and CP. The K5 values did not differ statistically among treatments. The mean K values varied between 0.20 and 3.70 cm/h. For CT, ..M was significantly greater than for CP and NT, following the same trend as K0. No differences in ..M were detected between CP and NT. With CT, the formation of water-conducting macropores with persistence until post-harvest was possible, while under CP preparation, the waterconducting macropores were not persistent. These results support the idea that tillage affects the soil water movement mainly by the resulting water-conducting macropores. Future studies on tillage effects on water movement should focus on macroporosity.; A importância da macroporosidade para o transporte de água no solo faz a sua avaliação de forma quantitativa uma tarefa desafiadora. Os valores da condutividade hidráulica (K) do solo em diferentes potenciais de retenção de água no solo e a quantificação de macroporos condutores de água (θM) em diferentes sistemas de preparo do solo proporcionarão melhor compreensão dos efeitos no arranjo de poros e nas propriedades físico-hídricas do solo. Dessa forma, o objetivo deste estudo foi avaliar os efeitos de um preparo convencional do solo com arado de aivecas (CT), com subsolador (CP) e utilizando um sistema com plantio direto (NT) sobre os atributos θM e K, bem como quantificar a contribuição da macroporosidade para o fluxo total de água em um solo franco. Um infiltrômetro de tensão no solo foi utilizado para emitir duas pressões ascendentes de água (-5 cm e 0 cm) para inferir θM e K, durante o pousio. A macroporosidade foi determinada com base na contribuição do fluxo entre os potenciais de água de 0 e -5 cm (K0 e K5, respectivamente), de acordo com a equação de Hagen-Poiseuille. Os valores da K0 obtidos foram estatisticamente superiores no preparo CT, quando comparados aos valores do NT e do CP. Os valores da K5 não diferiram estatisticamente entre os tipos de preparo. Os valores médios da K variaram entre 0,20 e 3,70 cm/h. A quantificação de macroporos condutores de água (θM) foi significativamente superior para o preparo CT em relação aos preparos CP e NT, seguindo a mesma tendência da K0. Não foram detectadas diferenças significativas dos valores de θM entre os preparos CP e NT. Utilizando o preparo CT, foi possível a formação de macroporos condutores de água com persistência até a pós-colheita; já no preparo CP, os macroporos condutores de água não foram persistentes. Os resultados apresentados sustentam a hipótese de que o sistema de preparo do solo escolhido altera o movimento da água no solo, principalmente, devido à formação de macroporos condutores de água. Estudos futuros sobre o efeito do sistema de preparo relacionado ao movimento da água no solo devem-se concentrar nas condições de formação da macroporosidade do solo.

Inactivation of tyrosinase photoinduced by pterin Dantola, Maria Laura; Gojanovich, Aldana Daniela; Thomas, Andrés Héctor Tyrosinase catalyzes in mammals the first and rate-limiting step in the biosynthesis of the melanin, the main pigment of the skin. Pterins, heterocyclic compounds able to photoinduce oxidation of DNA and its components, accumulate in the skin of patients suffering from vitiligo, a chronic depigmentation disorder in which the protection against UV radiation fails due to the lack of melanin. Aqueous solutions of tyrosinase were exposed to UV-A irradiation (350. nm) in the presence of pterin, the parent compound of oxidized pterins, under different experimental conditions. The enzyme activity in the irradiated solutions was determined by spectrophotometry and HPLC. In this work, we present data that demonstrate unequivocally that the enzyme is photoinactivated by pterin. The mechanism of the photosensitized process involves an electron transfer from tyrosinase to the triplet excited state of pterin, formed after UV-A excitation of pterin. The biological implications of the results are discussed.

Multi-century tree-ring based reconstruction of the Neuquén River streamflow, northern Patagonia, Argentina Mundo, Ignacio Alberto; Masiokas, Mariano Hugo; Villalba, Ricardo; Morales, Mariano Santos; Neukom, R.; Le Quesne, C.; Urrutia, R. B.; Lara, A. In most cases, gauged river flow records in southern South America extend for only a few decades, hampering the detection of long-term, decadal to centennial-scale cycles and trends. Long streamflow series can be reconstructed from tree-ring records, offering the opportunity of extending the limited hydrological instrumental data to several centuries. In northern Patagonia, Argentina, the Neuquén River has great importance for local and national socio-economic activities such as hydroelectric power generation, agriculture and tourism. In this study, new and updated tree-ring chronologies from Araucaria araucana and Austrocedrus chilensis are used to reconstruct the October-June mean streamflow for the Neuquén River and place the period of gauged flows (1903-2009), in a long-term, multi-century context. The reconstruction covers the period 1346-2000 AD and was developed from a network of 43 tree-ring chronologies, grouped in composite series, using a nested principal component regression approach. Analyses of the frequency, intensity, and duration of droughts and pluvial events indicate that the 20th century contains some of the driest and wettest annual to decadal-scale events in the last 654 yr, but longer and more severe events were recorded in previous centuries. Blackman-Tukey and singular spectral analyses identified quasiperiodic oscillations from 3.5 to 17.5 yr. A dominant 6.8-yr cycle explains ca. 23.6% of the total variance in the Neuquén River streamflow reconstruction. Correlation analyses showed that discharges of the Neuquén River are related to variations in the Southern Annular Mode (SAM), a measure of air mass exchanges between middle and high latitudes in the Southern Hemisphere. This association is consistent with previous studies that indicate a strong correlation between rainfall in northern Patagonia and SAM variations.

Implementation and evaluation of protocols translating: Methods for IPv4 to IPv6 transition Perez Monte, Cristian Federico; Robles, Maria Ines; Mercado, Gustavo Ariel; Taffernaberry, Juan Carlos; Orbiscay, Marcela Alejandra; Tobar, Mario Sebastián; Moralejo, Raúl; Pérez, Santiago Today millions of computers are interconnected using the Internet Protocol version 4 (IPv4) and can not switch to the new version, IPv6, simultaneously. For this reason the IETF has defined a number of mechanisms for transitioning to the new protocol in a progressively and controlled manner. On the other hand, Internet Service Providers (ISP) will not have new IPv4 global addresses to offer in the near future due to the fact that these addresses will be exhausted [1]. A very interesting alternative for ISPs is to use IPv6 global addresses and, by some transitional method, access the current IPv4 backbone. This study aims to compare two methods of transparent access to the IPv4 Internet backbone, from networks that are "IPv6 only". To make the comparison, a software was developed, implementing an Application Layer Gateway (ALG), and Ecdysis was used to implement NAT64. Both trials used a network IPv6 Test Bed. This paper details the design principles and fundamental aspects of the ALG implementation, as well as the implementation of NAT64. Finally, we present the tests performed and conclusions drawn on the test platform.

L'anthropologie théologique de Gaudium et spes Segovia, Juan Fernando Du concile Vatican II à aujourd’hui, la constitution Gaudium et spes1 a représenté la pierre angulaire de la doctrine sociale et politique de l’Eglise. Selon les termes de Jean-Paul II, elle est « la Magna Carta de la dignité humaine »2. Depuis 1965, « Gaudium et spes trace le visage d’une Église “intimement solidaire du genre humain et de son histoire”, qui chemine avec toute l’humanité et qui est sujette, avec le monde, au même sort terrestre, tout en étant “le ferment et, pour ainsi dire, l’âme de la société humaine appelée à être renouvelée dans le Christ et transformée en famille de Dieu” »3 . Quant à la clé de compréhension de Gaudium et spes, c’est la personne : « Tout [y] est considéré à partir de la personne et en direction de la personne, “seule créature sur terre que Dieu a voulue pour elle-même”. La société, ses structures et son développement doivent être +nalisés à “l’essor de la personne”. Pour la première fois, le Magistère de l’Église, à son plus haut niveau, s’exprime de manière aussi large sur les di0érents aspects temporels de la vie chrétienne : “On doit reconnaître que l’attention apportée par la Constitution aux changements sociaux, psychologiques, politiques, économiques, moraux et religieux a stimulé toujours plus […] la préoccupation pastorale de l’Église pour les problèmes des hommes et le dialogue avec le monde”

Caracterización altitudinal, uso y conservación de las Yungas subtropicales de Argentina; Altitudinal characterization, use and conservation of subtropical Yungas of Argentina Malizia, Lucio Ricardo; Pacheco, S.; Blundo, Cecilia Mabel; Brown, Alejandro Diego Las Yungas subtropicales se extienden por el noroeste de Argentina y sur de Bolivia, ocupando aproximadamente 56 000 km2. Se caracterizan por su amplia distribución altitudinal (400-2300 msnm), donde el recambio de especies de árboles determina la ocurrencia de tres pisos altitudinales (selva pedemontana, selva montana y bosque montano) con cambios consistentes en la fenología foliar y los síndromes de dispersión de las especies arbóreas. Dominan las especies caducifolias en los extremos del gradiente, y las especies semicaducifolias y siempreverdes en las elevaciones intermedias. Por su parte, las especies dispersadas por el viento o la gravedad caracterizan la parte baja del gradiente, mientras que las dispersadas por animales caracterizan los pisos superiores de vegetación. Los cambios físicos y biológicos en el gradiente altitudinal condicionan los usos y las estrategias de conservación de las Yungas subtropicales. La desforestación alcanzaba 18% de la superficie original de este ambiente en Argentina en la década de los 70 y 31% en el año 2010, principalmente (>90%) en las zonas bajas y planas. Las Yungas de Argentina presentan protección formal estatal (nacional, provincial y municipal) en 22% de su extensión actual, sin considerar las categorías internacionales, que pueden ser instrumentos valiosos, si se logra una implementación efectiva de los criterios de uso sustentable de los recursos naturales. Adicionalmente, los planes de ordenamiento territorial en marcha vinculados a compensaciones económicas podrían jugar un papel importante en el marco de estrategias regionales de uso y conservación.; Subtropical Yungas are distributed in northwestern Argentina and southern Bolivia over approximately 56000 km2. This vegetation type expands across a large altitudinal gradient (400-2300 m asl), where tree species turnover promotes the occurrence of three altitudinal belts (pre-montane forest, lower montane forest and upper montane forest), with associated changes in leaf phenology and dispersal syndromes. Deciduous tree species are dominant at the extremes of the gradient, and semi-deciduous and evergreen species are dominant at mid elevations. Alternatively, wind- and gravity-dispersed tree species characterize the lower part of the gradient, while animal-dispersed trees characterize the upper part of the gradient. Physical and biological changes along the altitudinal gradient determine uses and conservation strategies. Deforestation of subtropical Yungas reached 18% of the original distribution in Argentina during the 1970’s, and raised up to 31% by 2010, mainly (>90%) over low and flat areas. To date, 22% of the current distribution of Argentinean Yungas is formally protected (at national, provincial and municipal levels), not including international categories that may prove useful if sustainable-use criteria are successfully implemented. Additionally, land-use plans articulated with economic compensations might play a key role for planning regional use and conservation of subtropical Yungas.

Anisotropy and relaxation processes of uniaxially oriented CoFe2O4 nanoparticles dispersed in PDMS Antonel, Paula Soledad; Negri, Ricardo Martin; Leyva de Guglielmino, Ana Gabriela; Jorge, Guillermo Antonio When a uniaxial magnetic field is applied to a non-magnetic dispersive medium filled with magnetic nanoparticles, they auto-assemble into thin needles parallel to the field direction, due to the strong dipolar interaction among them. We have prepared in this way magnetically oriented nanocomposites of nanometer-size CoFe 2O 4 particles in a polydimethylsiloxane polymer matrix, with 10% w/w of magnetic particles. We present the characteristic magnetic relaxation curves measured after the application of a magnetic field forming an angle α with respect to the needle direction. We show that the magnetic viscosity (calculated from the logarithmic relaxation curves) as a function of α presents a minimum at α=0, indicating slower relaxation processes associated with this configuration of fields. The results seems to point out that the local magnetic anisotropy of the nanoparticles is oriented along the needles, resulting in the macroscopic magnetic anisotropy observed in our measurements.

Guiding authors to reliably use taxonomic names Bortolus, Alejandro It is widely known that every scientific work must be verifiable and repeatable by following the details included in the Materials and Methods section. Yet despite this, a high proportion of papers dealing with species in ecology and evolution omit the taxonomic materials and methods used to validate the names of the taxa mentioned, which is likely to have negative impacts on scientific ideas, global biodiversity, and human welfare.

Retroceso de la línea de costa en las Grütas, provincia de Río Negro; Retreat of the line of coast in Las Grutas, Río Negro province Kokot, Roberto Roque; Chomnalez, Florencia La localidad de Las Grutas, ubicada en la provincia de Río Negro, presenta una costa acantilada con una extensa plataforma litoral. Estas geoformas están constituidas por sedimentitas paleógenas correspondientes a la Formación Gran Bajo del Gualicho. Sobre las mismas se apoyan en discordancia erosiva depósitos de cordones litorales pleistocenos y la secuencia culmina con depósitos de dunas holocenos. Mediante la comparación de fotografías aéreas e imágenes satelitales, se determinó el grado de erosión entre los años 1969 y 2008. El retroceso fue estudiado a través de la comparación de fotografías aéreas e imágenes satelitales georreferenciadas. Los resultados muestran una tendencia a la reducción de los campos de dunas, al retroceso de las plataformas litorales y de la línea de costa. Esta última presenta una tasa de erosión media de 1,50 m en el lapso de 39 años. Sin embargo, los sectores céntricos y septentrionales fueron más afectados alcanzando hasta 3 m de retroceso en ese período. La erosión y los consecuentes procesos de remoción en masa responden principalmente a la intensa acción del oleaje sobre los afloramientos costeros, especialmente en los sectores de costa más expuestos a las rompientes, así como a los condicionantes geológico/estructurales de los afloramientos expuestos. El escenario de peligrosidad es acentuado por la acción antrópica que contribuye con la aceleración de los procesos naturales.; The town of Las Grutas, province of Río Negro, has a cliffed coastline with an extensive coastal platform. Mentioned land-forms are formed above Paleogene sedimentary rocks for the Gran Bajo del Gualicho Formation. Rely on them in erosive unconformity Pleistocene beach ridges deposits and the sequence ends with Holocene dune deposits. By comparing aerial photographs and satellite images, it was determined that the coast was eroded from 1969 to nowadays. The retreat was studied by comparing aerial photographs and georeferenced satellite imagery. The results show a downward trend of the dunes, the retreat of shore platforms and coastal shoreline. The latter has an average erosion rate of 1.50 m in 39 years. However, the central and northern sectors are most affected reaching up to 3 m setback in the same period. These erosion and resulting mass movement processes respond mainly to intense wave action on coastal outcrops, especially in coastal areas most exposed to the breakers, as well as the determining geological/structural outcrops exposed. The dangerous scenario is exacerbated by human action that contributes to the acceleration of the natural processes.

Fructose rich diet-induced high plasminogen activator inhibitor-1 (PAI-1) production in the adult female rat: Protective effect of progesterone Castrogiovanni, Daniel Cayetano; Alzamendi, Ana; Ongaro Gambino, Luisina; Giovambattista, Andres; Gaillard, Rolf C.; Spinedi, Eduardo Julio The effect of progesterone (P4) on fructose rich diet (FRD) intake-induced metabolic, endocrine and parametrial adipose tissue (PMAT) dysfunctions was studied in the adult female rat. Sixty day-old rats were i.m. treated with oil alone (control, CT) or containing P4 (12 mg/kg). Rats ate Purina chow-diet ad libitum throughout the entire experiment and, between 100 and 120 days of age drank ad libitum tap water alone (normal diet; CT-ND and P4-ND) or containing fructose (10% w/v; CT-FRD and P4-FRD). At age 120 days, animals were subjected to a glucose tolerance test or decapitated. Plasma concentrations of various biomarkers and PMAT gene abundance were monitored. P4-ND (vs. CT-ND) rats showed elevated circulating levels of lipids. CT-FRD rats displayed high (vs. CT-ND) plasma concentrations of lipids, leptin, adiponectin and plasminogen activator inhibitor-1 (PAI-1). Lipidemia and adiponectinemia were high (vs. P4-ND) in P4-FRD rats. Although P4 failed to prevent FRD-induced hyperleptinemia, it was fully protective on FRD-enhanced plasma PAI-1 levels. PMAT leptin and adiponectin mRNAs were high in CT-FRD and P4-FRD rats. While FRD enhanced PMAT PAI-1 mRNA abundance in CT rats, this effect was absent in P4 rats. Our study supports that a preceding P4-enriched milieu prevented the enhanced prothrombotic risk induced by FRD-elicited high PAI-1 production.

Los riesgos y las venturas del poeta contemporáneo: Dilemas en torno a la figura del escritor en la revista Poesía Buenos Aires (1950-1960) Bonano, Mariana El ideario vanguardista del grupo de escritores constituido en torno a la revista argentina Poesía Buenos Aires (1950-1960) puede ser delimitado a partir de las figuraciones acerca del poeta y de la labor creadora, presentes en los textos programáticos y de carácter ensayístico que la publicación recoge a lo largo de sus treinta números. Teniendo en cuenta aspectos de la doctrina susceptibles de ser vinculados con aquellos que las vanguardias históricas reivindican (compromiso vital, inconformismo, rechazo de todo tipo de convencionalismos), el presente trabajo examina la construcción en las páginas de la revista de un modelo de escritor próximo al arquetipo del "poeta maldito" conformado en la Modernidad y cultivado por las figuras más relevantes del simbolismo francés. En esta dirección, indaga en los retratos de poetas y propone que dichas figuraciones, en parte destinadas a fundamentar el valor de la empresa impulsada por los realizadores, dan cuenta al mismo tiempo del desgarramiento de los productores culturales quienes, situados frente la cultura de masas propiciada por el peronismo de la década de 1950, reivindican la "actitud ética" del escritor que hace de su creación un modo de vida y atribuyen a su práctica simbólica una misión redentora y liberadora. El artículo muestra que tal posicionamiento, pasible de ser identificado con el que asumen los miembros del grupo editor, no llega a resolver una de las problemáticas caras a la publicación: la de la constitución de una "poesía nueva" capaz de integrar la experiencia caótica del mundo contemporáneo y de restituir a la vez la comunicación esencial entre los hombres.

Estudio comparativo sobre los estilos de aprendizaje de estudiantes universitarios argentinos de diferentes disciplinas; Comparative study on the learning styles of argentine university students from different disciplines Ventura, Ana Clara; Moscoloni, Nora Ana Maria; Gagliardi, Raul Pedro La alfabetización académica exige el dominio progresivo de las formas textuales y discursivas propias de cada disciplina. El objetivo de este estudio es indagar los estilos de aprendizaje de estudiantes universitarios, estableciendo comparaciones según el tipo de episteme (Ciencias Humanas-Ciencias Exactas). Se realizó un estudio descriptivo-correlacional de corte transversal. Se aplicó el Inventario de Estilos de Aprendizaje de Felder y Soloman (1998) a 62 estudiantes de Ingeniería y 71 de Psicología de primer año de una universidad pública argentina. Los estudiantes inician su formación académica con distintos estilos de aprendizaje. Las discrepancias encontradas se acentuaron según el tipo de disciplina, y se obtuvieron diferencias estadísticamente significativas en los estilos de percepción (sensorial-intuitivo), representación (visual-verbal)y comprensión (secuencial-global). Los estudiantes de Ingeniería se definieron como sensoriales y visuales; en cambio, las orientaciones en Psicología son intuitivas, verbales y secuenciales. Implicancias educativas son discutidas.; Academic literacy requires the progressive mastery of textual and discursive forms of each discipline. The aim of this study is to analyze the learning styles of college students, comparing them by type of episteme (Human Sciences- Sciences). The research was a descriptive-correlational study with a transversal design. We applied the Index of Learning Styles of Felder & Silverman (1998) to 62 engineering students and 71 psychology students of first-year of a public university in Argentina. The main results show that students begin higher education with different learning styles. The discrepancies found were accentuated by the type of discipline; obtaining statistically significant differences in the styles of perception (sensory-intuitive), representation (visual-verbal) and comprehension (sequential-global).The engineering students were defined as sensory and visual. Instead, the guidelines in Psychology are intuitive, verbal, and sequential. Educational implications are discussed.

La Revista Porteña durante el período 1940-1960 Mauro, Karina Mariel; Libonati, Adriana El artículo realiza una caracterización de la denominada Revista Porteña durante el período 1940-1960. Con este fin, se establecen los rasgos distintivos del género, se examina la trayectoria de los principales capocómicos, vedettes, cantantes, coreógrafos y empresarios con desempeño durante las décadas estudiadas, y se analizan la recepción por parte del público y la crítica, y las relaciones establecidas entre la Revista y el contexto sociopolítico de la época.

Categorías económicas, prácticas sociales y percepciones en el mundo rural castellano (Siglos XIV-XV); Economic categories, social practices and perceptions in the Castillian rural (XIV-XV) Luchía, Corina Julia Las categorías de propiedad, posesión y trabajo en el mundo rural castellano asumen una dimensión práctica que sólo puede comprenderse desde el estudio de las condiciones que el medio natural impone a los agentes. Las percepciones que se reconocen en el ámbito que hemos investigado en los siglos bajomedievales remiten, por lo tanto, a las formas de estructuración de la dinámica de producción que importan la apropiación de los recursos; en particular, la disposición efectiva del principal medio de producción que es la tierra. Sobre esta cuestión en especial, señala E. P. Thompson que el campesino no sentía furiosamente (suponemos) que poseía su tierra, que era suya. Lo que él heredaba era un lugar en la jerarquía de derechos de aprovechamiento. Esa jerarquía de derechos, sobre los que la organización política tendrá una intervención activa para regularlos y garantizar los múltiples intereses que atraviesan el universo de aldeas y de pueblos, se halla sujeta a una lógica de subsistencia que recorre y determina las diversas actividades productivas que sostienen la reproducción de los tributarios; a la vez que posibilitan el mantenimiento de los distintos sectores de poder en el área castellana de realengo en los siglos recortados en esta colaboración.; The categories of ownership, possession and work in rural Castilian take a practical dimension that can only be understood from the study of the natural conditions imposed on agents. The perceptions are recognized in the area that we investigated in the late Medieval period refer, therefore, to ways of structuring the dynamics of production that matter the appropriation of resources, in particular the effective disposal of the principal means of production that is land. On this particular issue, said E. P. Thompson that the peasant "furiously was not (assume) that had their land, which was his. What he inherited was a place in the hierarchy of water rights. "This hierarchy of rights, on which the political will to regulate the active involvement of multiple interests and ensure that cross the universe of villages and towns, is subject to a subsistence logic that runs and determines the various productive activities that support reproduction of the tributaries, while possible to maintain the various branches of power in the Castilian royal area in the centuries cut in this collaboration.

Investigation of the impact of feeding Lactobacillus plantarum CRL 1815 encapsulated in microbially derived polymers on the rat faecal microbiota Jiménez Pranteda, María Luján; Aguilera, Margarita; Mc Cartney, Anne; Hoyles, Lesley; Jiménez-Valera, Maria; Nader, Maria Elena Fatima; Ramos Cormenzana, Alberto; Monteoliva Sánchez, Mercedes AIMS: The aim of this study was to evaluate the impact of the administration of microencapsulated Lactobacillus plantarum CRL 1815 with two combinations of microbially derived polysaccharides, xanthan : gellan gum (1%:0·75%) and jamilan : gellan gum (1%:1%), on the rat faecal microbiota. METHODS AND RESULTS: A 10-day feeding study was performed for each polymer combination in groups of 16 rats fed either with placebo capsules, free or encapsulated Lact. plantarum or water. The composition of the faecal microbiota was analysed by fluorescence in situ hybridization and temporal temperature gradient gel electrophoresis. Degradation of placebo capsules was detected, with increased levels of polysaccharide-degrading bacteria. Xanthan : gellan gum capsules were shown to reduce the Bifidobacterium population and increase the Clostridium histolyticum group levels, but not jamilan : gellan gum capsules. Only after administration of jamilan : gellan gum-probiotic capsules was detected a significant increase in Lactobacillus-Enterococcus group levels compared to controls (capsules and probiotic) as well as two bands were identified as Lact. plantarum in two profiles of ileum samples. CONCLUSIONS: Exopolysaccharides constitute an interesting approach for colon-targeted delivery of probiotics, where jamilan : gellan gum capsules present better biocompatibility and promising results as a probiotic carrier. SIGNIFICANCE AND IMPACT OF STUDY: This study introduces and highlights the importance of biological compatibility in the encapsulating material election, as they can modulate the gut microbiota by themselves, and the use of bacterial exopolysaccharides as a powerful source of new targeted-delivery coating material.

Effect of lyophilization and storage temperature on the activity of salivaricin CRL 1328, a potential bioactive ingredient of a urogenital probiotic product Vera Pingitore, Esteban; Bru Chauve, Elena Magdalena; Nader, Maria Elena Fatima Bacteriocins are antimicrobial peptides with potential applications as therapeutic agents for the treatment of microbial infections. The aim of this work was to investigate the effect of different protectors on the activity of salivaricin CRL1328, a bacteriocin produced by Lactobacillus salivarius CRL1328, during the lyophilization process and subsequent storage at different temperatures for 18 months using statistical models. Different protectors such as mannitol, Tween 80, polyethylene glycol 8000 (PEG), monosodium glutamate (MSG), reconstituted skim milk, sucrose and ascorbic acid were used for the lyophilization and storage of salivaricin. The biplot of principal component analysis was used for the interpretation of the interactions between the different factors studied. The antimicrobial activity of salivaricin was dependent mainly on temperature, and also on the time of storage and protector assayed. The stability of salivaricin was higher at -20°C and 4°C than 25°C and decreased during the time of storage; however, salivaricin was active after 18 months of storage at 25°C. Sucrose, mannitol plus sucrose, PEG plus sucrose and MSG were the most effective agents in protecting the bacteriocin during the lyophilization process. Effective maintenance of the activity of the bacteriocin was observed by storage with sucrose and ascorbic acid at –20°C as well as with PEG plus sucrose at 4°C and –20°C. The results obtained suggest that sucrose alone or combined with PEG can effectively maintain the activity of salivaricin during lyophilization and storage. This study provides useful information for the potential application of salivaricin as a bioactive principle for a pharmaceutical formulation.

Effects of chlorocholine chloride and paclobutrazol on cassava (Manihot esculenta Crantz cv. Rocha) plant growth and tuberous root quality; Efectos del cloruro de cloro colina y el paclobutrazol sobre el crecimiento de plantas y la calidad de raíces tuberosas de mandioca (Manihot esculenta Crantz cv. Rocha) Medina, Ricardo Daniel; Burgos, A.; Difranco, V.; Mroginski, Luis Amado; Cenóz, P. The effects of chlorocholine chloride (CCC) and paclobutrazol (PBZ) foliar application on shoot and root parameters of cassava field-grown plants were studied (0, 45 and 90 mg active ingredient per plant). CCC and PBZ reduced total plant and first branch height, aerial fresh mass and tuberous root number. PBZ delayed branching and significantly decreased tuberous root fresh mass, while CCC caused no modifications in these parameters. In addition, CCC and PBZ treatments did not modify tuberous root diameter, while PBZ reduced tuberous root length significantly. Starch content was increased by both growth regulators at the lower dose, whereas dry matter content was increased only by CCC. In conclusion, CCC suppresses excessive vegetative growth, favours quality attributes and does not alter yield, hence improving harvest index. Although PBZ at a low dose increases the starch content and harvest index, its effects on other parameters are undesirable.

La aparición y declinación del ausentismo como problema para el gobierno de la población trabajadora (Argentina, siglo XX); The emergence and decline of absenteeism as a problem for the government of the working population (Argentine, XX century) Haidar, Victoria En la actualidad, el ausentismo se ha borrado, casi completamente, del vocabulario de las ciencias del trabajo. Sin embargo, esa supresión no se corresponde con lo que sucede en plano de las prácticas del mundo del trabajo ni, tampoco, con las afirmaciones provenientes del discurso político; ámbitos en los que el ausentismo constituye, todavía, un objeto de preocupación. Frente a esas contradicciones, este artículo explora la problematización del ausentismo a lo largo del siglo XX en la Argentina a partir del análisis -en perspectiva histórica- de una serie de discursos. Luego de exhumar las condiciones que, a lo largo del siglo, posibilitaron tanto la aparición del ausentismo como problema, como su declinación, se recuperan las reflexiones e intervenciones que, en el presente, se refieren a él, con la finalidad de mostrar su continuidad y discontinuidad con aquellas estrategias y formas de pensar que, en otros períodos históricos, se movilizaron con la finalidad de gobernar la relación entre asistencia al trabajo, salud y productividad.; Currently, absenteeism has been erased almost entirely from the vocabulary of work science. However, this deletion does not correspond to what happens in the plane of labour's world practices, or, either, with statements from the political discourse; areas where absenteeism is still an object of concern. Faced with these contradictions, this article explores the problematization of absenteeism during the XX century in Argentine, analyzing, from a historical perspective, a series of discourses. After exhuming the conditions that, over the century, made possible both the emergence of absenteeism as a problem, as its decline, it recalls the reflections and interventions that, in the present, referring to absenteeism, in order to show its continuity and discontinuity with those strategies and ways of thinking that in other historical periods, were mobilized in order to govern the relationship between attendance at work, health and productivity.

Understanding the relationship between Mycobacterium bovis spoligotypes from cattle in Latin American Countries Zumárraga, Martín José; Arriaga, C.; Barandiaran, Soledad; Cobos Marín, Laura; de Waard, Jacobus; Estrada García, Inés; Figueiredo, T.; Figueroa, A.; Giménez, F.; Gomes, H. M.; Gonzalez y Merchand, J. A.; Macías, Analía; Milián Suazo, Feliciano; Rodríguez, C. A. R.; Santillán, M. A.; Suffys, P. N.; Trangoni, M. D.; Zárraga, A. M.; Cataldi, Ángel Adrián Spoligotyping is the most frequently used method for genotyping isolates of Mycobacterium bovis worldwide. In the current work, we compared spoligotypes from 1684 M. bovis isolates from Argentina (816), Brazil (412), Chile (66), Mexico (274) and Venezuela (116), obtained from cattle, humans, pigs, wild boars, farmed deer, goats, buffaloes, cats, and wild animals. A total of 269 different spoligotypes were found: 142 (8.4%) isolates presented orphan spoligotypes, whereas 1542 (91.6%) formed 113 different clusters. In cattle, SB0140 was the most representative spoligotype with 355 (24.6%) isolates, followed by SB0121 with 149 (10.3%) isolates. Clustering of spoligotypes ranged from 95.2% in Argentina to 85.3% in Mexico. Orphan spoligotypes were also variable, ranging from 23.7% in Mexico to 4.1% in Brazil. A large proportion of spoligotypes were common to the neighboring countries Argentina, Brazil and Chile. In conclusion, despite the diversity of spoligotypes found in the five countries studied, there are major patterns that predominate in these neighboring countries. These clusters may reflect a long-lasting active transmission of bovine tuberculosis or common historical origins of infection.

Seguridad social latinoamericana: nuevos derechos, nueva economía, ¿nueva democracia? Dvoskin, Nicolás En lo que refiere estrictamente a la seguridad social, el autor considera que el proceso de legitimación es lento, posiblemente mucho más lento que la deslegitimación voraz que provocó el neoliberalismo. Sin embargo, se ha iniciado ese camino en pos de sociedades latinoamericanas en las que la garantía de derechos sociales y derechos humanos sea algo legítimo y, por ende, reclamable. Estima que la nueva seguridad social latinoamericana está dando cuenta de que las privaciones sociales no son sólo responsabilidad de los individuos carentes y sus familias sino, por el contrario, de la sociedad toda, y por ende es ella la que ha de dar respuestas adecuadas. Agrega que si efectivamente se llegara al punto en el que no se cuestionara la legitimidad de estos reclamos, se estaría, ya con mayor convencimiento, hablando de una nueva democracia en América latina.