Influence of Hepatitis C virus coinfection on immune reconstitution in HIV subjects Badano, Maria Noel; Parodi, María Cecilia; Aloisi Zavala, Natalia Andrea; Corti, Marcelo; Elizalde de Bracco, María Marta; Baré, Patricia Despite successful HIV suppression by antiretroviral treatment (ART), immune activation may persist in HIV patients, contributing to an impaired immunological reconstitution and disease progression. Information regarding Hepatitis C virus (HCV) coinfection as a factor that accounts for immune activation in HIV subjects remains unclear. Furthermore, most studies have been carried out considering HIV/HCV patients as a whole, without taking into account the presence or absence of liver damage. Therefore, it is unknown if HCV and/or its liver-related disease could act as two independent factors contributing to the immune activation. In this study, we investigated the presence of immune activation in a cohort of 50 HIV/HCV patients by measuring cytokine levels, CD4+ T-cell counts and CD4/CD8 ratios. Six patient groups were defined according to HIV viral load, HCV status, and liver disease to assess the impact of each of these factors on immune activation and reconstitution in HIV/HCV patients. Only subjects with controlled HIV infection and cleared HCV displayed immunological parameters within normal ranges. The mere presence of HCV contributes to immune activation leading to an inappropriate immunological reconstitution. This state exacerbates in the presence of HCV-associated liver disease. Our results suggest that ART is not enough to suppress immune activation in the context of HIV/HCV coinfection, since both HCV and its liver-related disease would contribute to the immune activation. Given that immune activation worsens immunological reconstitution and clinical status, these results support the priority of HCV treatment in HIV/HCV patients and suggest the monitoring of their liver status.

The sensory machinery of the head louse pediculus humanus capitis: From the antennae to the brain Ortega Insaurralde, Isabel; Minoli, Sebastian Antonio; Toloza, Ariel Ceferino; Picollo, Maria Ines; Barrozo, Romina Insect antennae are sophisticated sensory organs, usually covered with sensory structures responsible for the detection of relevant signals of different modalities coming from the environment. Despite the relevance of the head louse Pediculus humanus capitis as a human parasite, the role of its antennal sensory system in the highly dependent relation established with their hosts has been barely studied. In this work, we present a functional description of the antennae of these hematophagous insects by applying different approaches, including scanning electron microscopy (SEM), anterograde antennal fluorescent backfills, and behavioral experiments with intact or differentially antennectomized lice. Results constitute a first approach to identify and describe the head louse antennal sensilla and to determine the role of the antenna in host recognition. SEM images allowed us to identify a total of 35–40 sensilla belonging to seven different morphological types that according to their external architecture are candidates to bear mechano-, thermo-, hygro-, or chemo-receptor functions. The anterograde backfills revealed a direct neural pathway to the ipsilateral antennal lobe, which includes 8–10 glomerular-like diffuse structures. In the two-choice behavioral experiments, intact lice chose scalp chemicals and warm surfaces (i.e., 32°C) and avoided wet substrates. Behavioral preferences disappeared after ablation of the different flagellomeres of their antenna, allowing us to discuss about the location and function of the different identified sensilla. This is the first study that integrates morphological and behavioral aspects of the sensory machinery of head lice involved in host perception.

Lipotoxicidad en músculo esquelético y su relación con la resistencia insulínica. Estudios en un modelo experimental de síndrome metabólico Oliva, Maria Eugenia; Ferreira Cordoneda, Maria del Rosario; Aiassa, Victoria; D´Alessandro, María Eugenia Introducción: el acúmulo de lípidos en el músculo esquelético seencuentra estrechamente vinculado con el desarrollo de la resistenciainsulínica. Esta última cumple un rol patogénico central enel desarrollo de numerosos desórdenes metabólicos incluidos enel síndrome metabólico.Objetivos: analizar algunas vías metabólicas implicadas en elacúmulo de lípidos en el músculo esquelético y su asociacióncon la resistencia insulínica en un modelo experimental quemimetiza el fenotipo del síndrome metabólico humano.Materiales y métodos: ratas macho Wistar recibieron una dietacontrol (DC) o una dieta rica en sacarosa (DRS) durante seismeses. Al final del período experimental se analizó en músculoesquelético gastrocnemio: contenido de triglicéridos (TG),acil-CoA de cadena larga y diacilglicerol, actividad enzimáticacarnitina palmitoil transferasa muscular (M-CPT1, M-CPT2 yM-CPT total) y masa proteica del PPARα, AMPK y AMPKp. Sedeterminaron los niveles séricos de TG, AGNE, glucosa, insulina,TNFα y adiponectina. La sensibilidad insulínica se midió porla técnica clamp euglucémica-hiperinsulinémica.Resultados: en los animales alimentados con DRS la dislipemia,hiperglucemia moderada, insensibilidad insulínica e incrementodel contenido de especies lipídicas en el músculo esqueléticose acompañaron de una disminución en la actividadenzimática M-CPT1 y M-CPT total, y un descenso de la masaproteica del PPARα. Además se observó una reducción de lamasa proteica de la AMPKp, la cual se correlacionó con bajosniveles de adiponectina y elevados niveles de TNFα séricos.Conclusiones: los resultados aportan nuevos datos sobre algunosmecanismos involucrados en el desarrollo de la lipotoxicidad en elmúsculo esquelético en ratas dislipémicas insulinorresistentes.

Juventudes y TIC: Estados locales frente al abordaje de la promoción de la lectura Pereyra, Eduardo Javier El presente artículo pone en discusión una serie de afirmaciones en torno a la supuesta “crisis de lectura” en las juventudes; las miradas clásicas respecto a qué, cómo y cuándo los jóvenes deben leer y respecto a los paradigmas más clásicos y conservadores sobre cómo se define y aborda la cuestión juvenil desde el Estado. A partir de ello, el objetivo central es dar relevancia a la capacidad de los Estados locales en el abordaje las tecnologías de la información y la comunicación (TIC) para intervenir en la promoción de la lectura implementando políticas públicas juveniles que se orienten a la generación de condiciones para que los jóvenes puedan autorealizarse y a su vez puedan participar en la construcción de la realidad social en la que se insertan.

Eco-friendly anti-felting treatment of wool top based on biosurfactant and enzymes Iglesias, Martín Sebastián; Sequeiros, Cynthia; García, Sebastián; Olivera, Nelda Lila Anti-felting processes with low environmental impacts are important for improving wool fiber attributes, especially if fiber is intended for the organic market. The aim of this study was to assess the potential of proteolytic enzymes, alone or in combination with Bacillus subtilis O9 biosurfactant (surfactin), to reduce felting of Merino wool top. Different concentrations of extracellular proteolytic extracts from Bacillus sp. G51 and Bacillus patagoniensis PATO5 T were used to treat wool top. As indicated by the felt-ball test results, a significant decrease in wool felting tendency was achieved using 50 and 150 Enzyme Units (EU)/g wool of PATO5 T and G51 proteases, respectively. Neither of these treatments caused a significant reduction in wool tensile strength. The addition of a pre-treatment step with biosurfactant surfactin, at a concentration above the Critical Micelle Concentration (CMC), further reduced felting tendency of wool. The combination of biosurfactant pre-treatment followed by B. patagoniensis PATO5 T protease treatment rendered the significantly smallest felt-ball density (0.049 ± 0.004 g/cm 3 ), without a significant loss in tensile strength. In PATO5 T proteolytic extract, enzyme aggregates ≥100 kDa account for about 50% of the proteolytic activity. This could reduce the velocity of protease diffusion into wool fiber, promoting its action on wool surface. According to our knowledge, this is the first report that demonstrates the usefulness of a biosufactant in an environmental-friendly process aimed at reducing wool top felting.

White y Ricoeur: dos visiones ejemplares sobre la narrativa histórica; White and Ricoeur: two exemplary visions of historical narrative Navarro, Jorge Fernando Hayden White, iniciador de lo que hoy se conoce como el narrativismo, sostiene que toda experiencia puede ser narrada y, en tal sentido, defiende un enfoque formal y textualista para pensar la filosofía de la historia. De este modo, en tanto el relato histórico es considerado una forma discursiva dirigida a la audiencia del presente, el problema de la verdad de lo relatado pierde centralidad. Contra la devaluación del acontecimiento, Paul Ricoeur, en cambio, ha mostrado la riqueza de sostener una simbiosis intelectual entre el concepto de narración y el de acontecimiento, sin que ello signifique concebir a este último como algo efectivamente producido en el pasado. Este artículo se propone exponer los argumentos centrales respecto del problema crucial de la narración histórica, que es sustentada por cada uno de los filósofos. Además y, fundamentalmente, analizar las razones esgrimidas por Ricoeur para criticar el narrativismo de White.; Hayden White, initiator of what is now known as narrativism, argues that all experience can be narrated and, in that sense, defends a formal and textualist approach to think about the philosophy of history. Thus, while the historical account is considered a discursive form addressed to the audience of the present, the problem of the truth of the story loses centrality. Against the devaluation of the event, Paul Ricoeur, on the other hand, has shown the richness of sustaining an intellectual symbiosis between the concept of narration and that of event, without this meaning conceiving the latter as something actually produced in the past. This article intends to present the central arguments regarding the crucial problem of historical narration, which is supported by each of the philosophers. In addition it analyzes the reasons put forward by Ricoeur to criticize White's narrativism...

Subcritical fluid extraction of antioxidant phenolic compounds from Pistachio (Pistacia vera L.) Nuts: Experiments, modeling, and optimization Bodoira, Romina Mariana; Velez, Alexis; Rovetto, Laura Jorgelina; Ribotta, Pablo Daniel; Maestri, Damian; Martinez, Marcela Lilian A process to obtain phenolic compounds with antioxidant properties from pistachio nuts using water/ethanol mixture under high temperature and pressure conditions was carried out. To optimize extraction conditions and antioxidant activity of bioactive compounds, theoretical models were scanned against experimental data. Phenolic profile was dominated by several flavonoids and gallic acid derivatives. A fitted model for phenolic compounds extraction presented a maximum predicted value under the following conditions: 220 °C extraction temperature, 6.5 MPa pressure, and 50% ethanol. Beneath these conditions, phenolic extracts gave the highest radical scavenging capacity, similar to that reached by using commercial antioxidants. A mathematical model, namely two-site desorption kinetic model, showed to be suitable for the description of extraction kinetics under the optimal operation conditions. Overall, the process described in this study shows a potential alternative method for extraction of pistachio bioactive compounds. Practical Application: Pistachio nuts are known to contain a vast array of phenolic and polyphenolic substances having strong antioxidant properties. Currently, the use of natural antioxidants in the food industry has increased, in consequence there is a growing interest in improving the extraction processes using GRAS (general recognize as safe) solvents. This study describes a safe, inexpensive, and short-time method (subcritical fluid extraction) to obtain antioxidant extracts from defatted pistachio nuts. This type of process may be adapted toward applications at industrial scale.

Enhancement of composition and oxidative stability of Chia (Salvia hispanica L.) seed oil by blending with specialty oils Bordón, María Gabriela; Meriles, Silvina Patricia; Ribotta, Pablo Daniel; Martinez, Marcela Lilian Chia seed (Salvia hispanica L.) oil is mainly composed of ω-3 fatty acids (61% to 70%). Despite being nutritionally favorable, higher amounts of polyunsaturated fatty acids result in poorer oxidative stability. Thus, the aim of this work was to produce edible vegetable oil blends rich in ω-3 fatty acids and with greater oxidative stability than pure chia oil. Blending of chia with other specialty oils (walnut, almond, virgin, and roasted sesame oils) was assessed in the following respective proportions: 20:80, 30:70, and 40:60 (v/v). An accelerated storage test was conducted (40 ± 1 °C, 12 days). Primary and secondary oxidation products, free fatty acid content, antioxidant compounds, fatty acid composition, and induction time were determined. The blends presented higher oxidative stability indices than chia oil. Sensory analysis showed that, given a pure oil, judges did not identify statistically significant differences among the blends. The results suggest that blending of chia oil is an adequate alternative to obtain ω-3-enriched oils with higher oxidative stability indices. Practical Application: Vegetable oil blending is a widely used practice in the edible oil industry to produce blended oils with enhanced stability and nutritional and sensory properties at affordable prices. The blends developed in this study from chia, sesame, walnut, and almond oils take advantage of the properties of each parent oil to yield products with improved oxidative stability, essential fatty acid presence, and sensory characteristics. To achieve a daily intake of 2.22 g/day of ω-3 fatty acids as recommended by the Intl. Society for the Study of Fatty Acids and Lipids (ISSFAL), it is necessary to consume approximately one spoonful of the formulated mixtures.

Environmental constraints to native woody species recruitment in invaded mountain woodlands of central Argentina Ferreras, Ana Elisa; Whitworth Hulse, Juan Ignacio; Tecco, Paula Andrea; Marcora, Paula Inés; Funes, Guillermo Nowadays forests, which were formerly considered resistant to invasion due to its shady understories, are been transformed to invaded landscapes. Thus, the aim of this study was to evaluate the regeneration of native woody species in Ligustrum lucidum invaded woodlands. In addition, we aim to identify the main environmental differences between the native and invaded woodlands and evaluate the effect of those conditions in the regeneration phase of dominant native woody species. Finally, we analyze how is the emergence and survival of the exotic species in relation to that exhibited by native species in both environmental situations. For this, we performed a seed addition experiment placing three native woody species (Celtis ehrenbergiana, Lithraea molleoides, Vachellia caven) and the dominant exotic (L. lucidum) in native and invaded woodlands of the Chaco mountains, central Argentina. Also, we performed a laboratory experiment simulating the differences in light recorded at the field (main abiotic difference between both woodland types). Our field experiment indicated that, if seeds are actively added, the percentage of seedlings emergence of native species could be similar in invaded and native woodlands. However, we observed a trend of lower seedling survival after winter within the exotic monospecific stands, which was significant only for the native species C. ehrenbergiana. We suggest that this constraint could be partly related to the shadier conditions imposed by L. lucidum, since this is the major environmental change within the invaded woodlands in comparison with native ones. Consistently, the experimental simulation showed that the increased in shade reduced the overall growth of seedlings. As was mostly observed in temperate biome, our study in a subtropical seasonally dry region indicates that invaded areas may not affect the emergence stage but limit the survival of seedlings. Among the native species, C. ehrenbergiana seems to be the most suitable species to start restoration, showing the highest performance throughout the year. Combined actions of seed addition and canopy opening might counteract the abiotic constraint and contribute to restoration success of this invaded landscape.

Production planning and scheduling in Cyber-Physical Production Systems: a review Rossit, Daniel Alejandro; Tohmé, Fernando Abel; Frutos, Mariano The study of scheduling procedures has generated important contributions to the improvement of productivity in different industrial branches. In recent years, the incorporation of high technology to production systems brought the advent of a ‘fourth industrial revolution’, Industry 4.0. One of the mainstays of Industry 4.0 is the application of Cyber-Physical Systems (CPS), which are physical production systems that incorporate sophisticated computational tools. This implies embedding computers, enabling a real-time connection between workstations and Decision Support Systems. It seems natural, in this setting, to associate scheduling schemes to CPS. This allows streamlining the decision-making process, allowing more flexible and lean production lines. We review here the most salient contributions on scheduling in these environments. We distinguish between work on the basic issues of scheduling and that on scheduling as part of higher-level production planning activities. To frame correctly this distinction we analyse how CPS can embody the different levels of the ISA-95 structure and how this relates to the classical structure of production planning. Our review suggests that the real-time availability of information will have a significant impact in this area and that scheduling will be solved in the future in decentralised decision processes.

mPRs represent a novel target for PRL inhibition in experimental prolactinomas Camilletti, María Andrea; Abeledo Machado, Alejandra Inés; Perez, Pablo A.; Faraoni, Erika Yanil; de Fino, Fernanda Teresa; Rulli, Susana Beatriz; Ferraris, Maria Jimena; Pisera, Daniel Alberto; Gutiérrez, Silvina; Thomas, Peter Bruno Kurt; Diaz, Graciela Susana Membrane progesterone receptors are known to mediate rapid nongenomic progesterone effects in different cell types. Recent evidence revealed that mPRα is highly expressed in the rat pituitary, being primarily localized in lactotrophs, acting as an intermediary of P4-inhibitory actions on prolactin secretion. The role of mPRs in prolactinoma development remains unclear. We hypothesize that mPR agonists represent a novel tool for hyperprolactinemia treatment. To this end, pituitary expression of mPRs was studied in three animal models of prolactinoma. Expression of mPRs and nuclear receptor was significantly decreased in tumoral pituitaries compared to normal ones. However, the relative proportion of mPRα and mPRβ was highly increased in prolactinomas. Interestingly, the selective mPR agonist (Org OD 02-0) significantly inhibited PRL release in both normal and tumoral pituitary explants, displaying a more pronounced effect in tumoral tissues. As P4 also regulates PRL secretion indirectly, by acting on dopaminergic neurons, we studied mPR involvement in this effect. We found that the hypothalamus has a high expression of mPRs. Interestingly, both P4 and OrgOD 02-0 increased dopamine release in hypothalamus explants. Moreover, in an in vivo treatment, that allows both, pituitary and hypothalamus actions, the mPR agonist strongly reduced the hyperprolactinemia in transgenic females carrying prolactinoma. Finally, we also found and interesting gender difference: males express higher levels of pituitary mPRα/β, a sex that does not develop prolactinoma in these mice models. Taken together these findings suggest mPRs activation could represent a novel tool for hyperprolactinemic patients, especially those that present resistance to dopaminergic drugs.

Switching Divergences for Spectral Learning in Blind Speech Dereverberation Ibarrola, Francisco Javier; Spies, Ruben Daniel; Di Persia, Leandro Ezequiel When recorded in an enclosed room, a sound signal will most certainly get affected by reverberation. This not only undermines audio quality, but also poses a problem for many human-machine interaction technologies that use speech as their input. In this paper, a new blind, two-stage dereverberation approach based in a generalized beta-divergence as a fidelity term over a non-negative representation is proposed. The first stage consists of learning the spectral structure of the signal solely from the observed spectrogram, while the second stage is devoted to model reverberation. Both steps are taken by minimizing a cost function in which the aim is put either in constructing a dictionary or a good representation by changing the divergence involved. In addition, an approach for finding an optimal fidelity parameter for dictionary learning is proposed. An algorithm for implementing the proposed method is described and tested against state-of-the-art methods. Results show improvements for both artificial reverberation and real recordings.

Nuclear receptors: a historical perspective Mazaira, Gisela Ileana; Zgajnar, Nadia Romina; Lotufo, Cecilia Maricel; Daneri Becerra, Cristina del Rosario; Sivils, Jeffrey C.; Soto, Olga B.; Cox, Marc B.; Galigniana, Mario Daniel These receptors exhibit a multitude of roles in cell biology and hence have attracted a great deal of interest in the drug discovery field. It is not certain whether these receptors evolved independently or an ancestral protein acquired various functions upon binding to preexisting small molecules, ligands. Currently, members of this receptor superfamily are categorized in six groups, including ?orphan receptors.? Research in the area has resulted in several clinically used drugs and continues to reveal further previously unknown roles for these receptors paving the road toward more valuable discoveries in the future.

The geopolitics of moral panic: The influence of Argentinian neo-conservatism in the genesis of the discourse of 'gender ideology' Moran Faundes, Jose Manuel Ferrucio ´Gender Ideology´ discourse has been one of the most recurrent strategies of neo-conservative activism at a global level. Through this syntagma, a variety of moral panics are mobilized against feminist agendas and LGBTI rights, accusing them of promoting the destruction of natural order, the spread of Marxism and global conspiracy. Academic literature has highlighted that the genesis of this strategic discourse was an intellectual production in the mid-1990s; we can trace back texts written in conjunction by secular neo-conservative intellectuals in the United States and members of the Catholic hierarchy. However, the tendency was to ignore the strong intellectual production that neo-conservative activists developed at that time in Argentina, particularly in Córdoba and Buenos Aires, which helped to lay the foundations of the present ´gender ideology´ discourse. The intention of this work is to draw attention to that local production and its connection with the ideas that were being developed in parallel in the global North. In order to do this, we will analyze a series of texts produced by neo-conservatives in Argentina in the 1990s.

ELSA cohort 2014: Association of age of first drink and progression from first drink to drunkenness on alcohol outcomes in Argentinean college freshmen Vera, Belén del Valle; Pilatti, Angelina; Pautassi, Ricardo Marcos College freshman are at-risk for hazardous alcohol drinking and for experiencing alcohol-related negative consequences. This is exacerbated in those featuring an early age of first alcohol use or of first drunkenness. It remains unclear which of these milestones is more strongly associated with alcohol outcomes. We examined, in Argentinean college drinkers (n = 4088; 43% men; racially and ethnically homogeneous), the association of age at drinking onset and progression to drunkenness (drunkenness naïve [Drunk-Naïve]; No-Delay [same age of first alcohol use and first alcohol intoxication]; one year of delay between age of first alcohol use and first alcohol intoxication; ≥2years of delay) on several alcohol outcomes. Methods: A survey measured substance use, age at drinking and drunkenness onset and alcohol-related consequences. Results: Alcohol consumption per drinking occasion was significantly greater in men than in women. An early drinking onset (alcohol use before age 13) and lifetime drunkenness independently exacerbated alcohol consumption per drinking occasion and during the last year. In men, Early-Onset was associated with a greater number of alcohol-related consequences when the delay between Early-Onset and the first drunkenness episode was 1 or ≥2 years yet did not significantly alter the number of negative consequences in Drunk-naïve or No-delay drinkers. In women, Early-Onset significantly enhanced the number of negative consequences when the delay was two years, but not when the delay was one-year or in Drunk-naïve or No-delay drinkers. Conclusions: The window between the first contact with alcohol and the first episode of drunkenness is a critical period to reduce alcohol-related problems.

Whey protein-kefiran films as driver of probiotics to the gut Gagliarini, Nina María; Diosma, Gabriela; Garrote, Graciela Liliana; Abraham, Analia Graciela; Piermaria, Judith Araceli In this work, an alternative matrix for probiotics delivery constituted by whey proteins and polysaccharide kefiran was investigated. Edible transparent and homogeneous films containing the microorganisms Lactobacillus paracasei CIDCA 8339 and Kluyveromyces marxianus CIDCA 8154 with probiotic characteristics have been developed. Inclusion of microorganisms did not modify thickness, color or mechanical characteristics of films. This matrix showed good capability protecting the included probiotics from stress during film obtaining process and through gastrointestinal passage simulation. At the end of the applied gastrointestinal tract model, 7.1.105 CFU/ cm2 K. marxianus CIDCA 8154 and 1.65.107 CFU/cm2 L. paracasei CIDCA 8339 remain viable, having decreased less than 0.6 logarithm cycle with respect to those originally included, even after 57 days of films storage.

Fabrication and Characterization of Hollow Microcapsules from Polyelectrolytes Bearing Thymine Pendant Groups for Ultraviolet-B (UVB)-Induced Crosslinking Gimenez, Rodrigo Esteban; Serrano, Mariana Paula; Alvarez, Rosa Maria Susana; Martino, Debora Marcela; Borsarelli, Claudio Darío DNA - bioinspired polyelectrolytes poly[vinylbenzylthymine (VBT)-4-vinylbenzyltriethylammonium chloride (VBA)] and poly[vinylbenzylthymine (VBT)-4-vinylphenylsufonate (VPS)] were used for the preparation of hollow microcapsules (HMC) using the layer-by-layer method and CaCO3 microspheres as removable molds. Stable aqueous suspensions of spherical-shaped HMCs with a shell composed of six layers of VBA-based polyelectrolytes were obtained, of approximately (7.0±1.5) μm diameter and a shell thickness of 1 μm. Ultraviolet-B irradiation of the HMC suspensions induces an efficient crosslinking between adjacent polyelectrolyte chains through the formation of thymine photodimers, such as the cyclobutane pyrimidine dimer (CPD) and the (6?4) pyrimidine?pyrimidone photoproduct (6?4PP). This process resulted in a reduction of the average interstitial mesh size of the HMC shells, modulating their permeability properties and increasing the mechanical stability of the HMC without a noticeable modification of size and shape. Thus, the DNA-bioinspired polyelectrolytes are promising materials for the preparation of UVB-responsive HMCs.

Brittle stars from the Lower Cretaceous of Patagonia: first ophiuroid articulated remains for the Mesozoic of South America; Ofiuroideos del Cretácico Inferior de Patagonia: primer registro fósil articulado para el Mesozoico de América del Sur Fernández, Diana Elizabeth; Giachetti, Luciana María; Stöhr, Sabine; Thuy, Ben; Perez, Damián; Comerio, Marcos; Pazos, Pablo Jose The first articulated remains of ophiuroids for the Mesozoic of South America are described from the Lower Cretaceous of Neuquén Basin, Argentina. The taxonomic analysis allows the assignment of the material described herein to the extinct genus Ophiopetra. The specimens belong to a new species, but considering the poor preservation, a new name is not introduced, as it would be based on an incomplete diagnosis. Certain characteristics (e.g., the diameter of the disc, the width/height ratio of the vertebrae) suggest that these ophiuroids are paedomorphic specimens. In light of the latest classification of the Ophiuroidea, and new insights on the spine articulation microstructure of Ophiopetra lithographica presented herein, a transfer of Ophiopetra to the family Ophionereididae within the order Amphilepidida is proposed. This material expands the palaeogeographic record of this genus, since it represents the first remains of Ophiopetra described in the Southern Hemisphere. It is also the first Cretaceous record of the genus worldwide.

Germination response to osmotic potential, osmotic agents, and temperature of five halophytes occurring along a salinity gradient Piovan, María Julia; Pratolongo, Paula Daniela; Donath, Tobias W.; Loydi, Alejandro; Eckstein, Rolf Lutz Premise of research. Halophyte species grow where salt concentrations are high. Still, their germination may be affected by salts, either by creating an osmotic potential that prevents water uptake or by dissociating in ions that can cause different grades of toxicity. With the increase of salinized areas, it becomes important to understand the behavior of these species. Methodology. We studied how the germination of five halophyte species that occur along a salinity gradient in the Bahía Blanca coastal zone, Atriplex undulata, Cyclolepis genistoides, Allenrolfea patagonica, Sarcocornia perennis, and Heterostachys ritteriana, responds to variations in osmotic agents, osmotic potential, and temperature. Seeds were exposed to different osmotic potentials using NaCl (neutral salt), Na2CO3 (alkaline salt), and mannitol solutions in a germination chamber experiment. Germination was recorded during 42 d. Germination percentage, mean germination time, and synchrony were calculated. Pivotal results. Our experimental results showed that for the five halophyte species under study, germination was mostly driven by osmotic potentials and osmotic agents. At high osmotic potential, the germination response did not differ significantly from controls, except for Allenrolfea and Cyclolepis, which showed lower germination when treated with Na2CO3. Low osmotic potentials and Na2CO3 were detrimental to germination, reflected by lower germination percentages, higher mean germination times, and lower synchrony. Conclusions. In general, the response to the alkaline salt was more negative than that to the neutral salt or mannitol, regardless of the species. Each species showed a different response to the salts under study, and this response matched well with the distribution of species along the salinity gradient observed in the field.

Biomimetic Cu, Zn and Cu2 complexes inserted in mesoporous silica as catalysts for superoxide dismutation Patriarca, Matías Ezequiel; Daier, Veronica Andrea; Camí, Gerardo Enrique; Pellegri, Nora Susana; Rivière, Eric; Hureau, Christelle; Signorella, Sandra Rosanna Three CuZn-superoxide dismutase (SOD) functional mimics, [CuZn(dien)2(μ-Im)](ClO4)3 (1), [Cu2(dien)2(μ-Im)](ClO4)3 (2) (Im = imidazole, dien = diethylenetriamine), and [CuZn(salpn)Cl2] (3) (H2salpn = 1,3-bis(salicylideneamino)propane), were successfully inserted into the nanochannels of SBA-15 type mesoporous silica with retention of the silica mesostructure. X-ray absorption spectroscopic studies indicate that the encapsulated complexes keep unchanged the first-shell environment of Cu(II) and Zn(II) ions. Magnetic measurements suggest that the nanochannels constrain the geometry of the μ-imidazolate-Cu(II)2 core modifying the relative orientation of the two copper coordination planes. Confinement imposed by the silica nanochannels upon encapsulation of complexes 1 and 2 leads to stable hybrid materials at physiological pH with enhanced SOD activity relative to the free complexes. Unlike the imidazolato-bridged compounds, insertion of 3 in mesoporous silica leads to a less stable hybrid material exhibiting partial release into the aqueous solution and O2•− dismutation rate slower than the free complex. The covalent binding of a mononuclear Cu(dien)Im+ moiety to the mesoporous silica showed lower SOD activity than encapsulated imidazolato-bridged CuZn and Cu2 complexes. The results emphasize the positive effect of encapsulation on SOD activity of imidazolato-bridged dinuclear complexes.