CONICET Digital

Nuclear quantum effects on the structure and the dynamics of [H2O]8 at low temperatures

Nuclear quantum effects on the structure and the dynamics of [H2O]8 at low temperatures Videla, Pablo Ernesto; Rossky, Peter J.; Laria, Daniel Hector We use ring-polymer-molecular-dynamics (RPMD) techniques and the semi-empirical q-TIP4P/F water model to investigate the relationship between hydrogen bond connectivity and the charac- teristics of nuclear position fluctuations, including explicit incorporation of quantum effects, for the energetically low lying isomers of the prototype cluster [H2O]8 at T = 50 K and at 150 K. Our results reveal that tunneling and zero-point energy effects lead to sensible increments in the magnitudes of the fluctuations of intra and intermolecular distances. The degree of proton spatial delocalization is found to map logically with the hydrogen-bond connectivity pattern of the cluster. Dangling hydro- gen bonds exhibit the largest extent of spatial delocalization and participate in shorter intramolecular O-H bonds. Combined effects from quantum and polarization fluctuations on the resulting individ- ual dipole moments are also examined. From the dynamical side, we analyze the characteristics of the infrared absorption spectrum. The incorporation of nuclear quantum fluctuations promotes red shifts and sensible broadening relative to the classical profile, bringing the simulation results in much more satisfactory agreement with direct experimental information in the mid and high fre- quency range of the stretching band. While RPMD predictions overestimate the peak position of the low frequency shoulder, the overall agreement with that reported using an accurate, parame- terized, many-body potential is reasonable, and far superior to that one obtains by implementing a partially adiabatic centroid molecular dynamics approach. Quantum effects on the collective dynam- ics, as reported by instantaneous normal modes, are also discussed

Development of a novel methodology for cryopreservation of melanoma cells applied to CSF470 therapeutic vaccine

Development of a novel methodology for cryopreservation of melanoma cells applied to CSF470 therapeutic vaccine Tapia, Ivana Jaqueline; Aris, Mariana; Arriaga, Juan Martín; Blanco, Paula A.; Mazzobre, Maria Florencia; Vega, Julio; Mordoh, Jose; Barrio, Maria Marcela CSF470 vaccine is a mixture of four lethally irradiated melanoma cell lines, administered with BCG and GM-CSF, which is currently being tested in a Phase II/III Clinical trial in stage II/III melanoma patients. To prepare vaccine doses, irradiated melanoma cell lines are frozen using dimethyl sulfoxide (Me2SO) and stored in liquid nitrogen (liqN2). Prior to inoculation, doses must be thawed, washed to remove Me2SO and suspended for clinical administration. Avoiding the use of Me2SO and storage in liqN2 would allow future freeze-drying of CSF470 vaccine to facilitate pharmaceutical production and distribution. We worked on the development of an alternative cryopreservation methodology while keeping the vaccine’s biological and immunogenic properties. We tested different freezing media containing trehalose suitable to remain as excipients in a freeze-dried product, to cryopreserve melanoma cells either before or after gamma irradiation. Melanoma cells incorporated trehalose after 5 h incubation at 37 °C by fluid-phase endocytosis, reaching an intracellular concentration that varied between 70–140 mM depending on the cell line. Optimal freezing conditions were 0.2 M trehalose and 30 mg/ml human serum albumin, at −84 °C. Vaccine doses could be frozen in trehalose at −84 °C for at least four months keeping their cellular integrity, antigen expression and apoptosis/necrosis profile after gamma-irradiation as compared to Me2SO control. Non-irradiated melanoma cell lines also showed comparable proliferative capacity after both cryopreservation procedures. Trehalose-freezing medium allowed us to cryopreserve melanoma cells, either alive or after gamma irradiation, at −84 °C avoiding the use of Me2SO and liqN2 storage. These cryopreservation conditions could be suitable for future freeze-drying of CSF470 vaccine.

La interacción entre las instituciones y la producción cinematográfica y de contenidos para TV en Córdoba

La interacción entre las instituciones y la producción cinematográfica y de contenidos para TV en Córdoba Motta, Jorge; Morero, Hernan; Mohaded, Nicolás Mariano El objetivo del presente trabajo es estudiar la manera en que en los últimos años se ha dado el proceso de interacción entre las instituciones y las productoras audiovisuales y cinematográficas de la ciudad de Córdoba, afectando el grado de desarrollo de las competencias locales. El análisis se basa en un estudio exploratorio cualitativo centrado en entrevistas a productoras de cine y/o TV; y en entrevistas a diversos informantes clave del sector. El estudio revela que el desempeño reciente ha sido acompañado por la emergencia de una importante serie de instancias colectivas e institucionales de sostenimiento, creación y fortalecimiento de competencias.; This paper focuses on the interaction between institutions and media production in terms of the development of local production in Cordoba City (Argentina). The analysis is based on a qualitative exploratory approach that focuses on interviews to film and television producers as well as to other key sector informants. The paper reveals the recent emergence of significant collective and institutional actions that support, create, and strengthen local production.

Geografía: desarrollo local y regional

Geografía: desarrollo local y regional Conte, Analia Silvia El propósito que plantea este editorial es mostrar cómo, una serie de tendencias geográficas, históricas, políticas, económicas y hasta epistemológicas, han convergido durante los últimos años para construir un nuevo paradigma del desarrollo, de suma importancia para la geografía y para su intervención en lo que respecta al territorio. La necesidad de insertar el desarrollo local en el marco territorial regional, nacional y supranacional puede obtener de la acción profesional de los geógrafos, una contribución fundamental.

Lista de sírfidos afidófagos y primeros registros de Pseudodoros clavatus y Eupeodes rojasi (Diptera: Syrphidae), potenciales agentes de control biológico en la provincia de Mendoza, Argentina

Lista de sírfidos afidófagos y primeros registros de Pseudodoros clavatus y Eupeodes rojasi (Diptera: Syrphidae), potenciales agentes de control biológico en la provincia de Mendoza, Argentina; List of aphidophagous sirfids and new records of Pseudodoros clavatus and Eupeodes rojasi (Diptera: Syrphidae), potential agents for biological control from Mendoza, Argentina López García, Guillermo Pablo; Maza, Noelia This scientific note reports the first faunistic list of aphidophagous sirfids from Mendoza and new records of Pseudodoros clavatus Fabricius and Eupeodes rojasi Marnef, potential agents for biological control.

Mathematical modeling and simulation of soluble protein extraction during leaching process in surimi elaboration

Mathematical modeling and simulation of soluble protein extraction during leaching process in surimi elaboration Reinheimer, Maria Agustina; Medina, J. R.; Scenna, Nicolas Jose; Mussati, Sergio Fabian; Freyre, M.; Perez, Gustavo Alberto This work presents a mathematical model to simulate the extraction process of soluble protein from sábalo (Prochilodus platensis) during the surimi elaboration. The mathematical model consists of both partial differential and algebraic equations. Central finite difference method and the explicit scheme were applied to discretize the partial differential equation. The resulting model was implemented into the optimization environment General Algebraic Modeling System (GAMS). Experimental data obtained from laboratory scale using sábalo as raw material, was used to verify the output results of the proposed model. A good agreement between experimental and simulated extraction yields was obtained (R2 = 0.9552). Once validated, the model was used to investigate the influence of several parameters such as, particle?s diameter, volume fraction of the solvent, residence time and agitation velocity on the extraction efficiency. The results are presented and discussed through different case studies.

The formin FHOD1 and the small GTPase Rac1 promote vaccinia virus actin-based motility

The formin FHOD1 and the small GTPase Rac1 promote vaccinia virus actin-based motility Alvarez, Diego Ezequiel; Agaisse, Herve Vaccinia virus dissemination relies on the N-WASP– ARP2/3 pathway, which mediates actin tail formation underneath cell-associated extracellular viruses (CEVs). Here, we uncover a previously unappreciated role for the formin FHOD1 and the small GTPase Rac1 in vaccinia actin tail formation. FHOD1 depletion decreased the number of CEVs forming actin tails and impaired the elongation rate of the formed actin tails. Recruitment of FHOD1 to actin tails relied on its GTPase binding domain in addition to its FH2 domain. In agreement with previous studies showing that FHOD1 is activated by the small GTPase Rac1, Rac1 was enriched and activated at the membrane surrounding actin tails. Rac1 depletion or expression of dominant-negative Rac1 phenocopied the effects of FHOD1 depletion and impaired the recruitment of FHOD1 to actin tails. FHOD1 overexpression rescued the actin tail formation defects observed in cells overexpressing dominant-negative Rac1. Altogether, our results indicate that, to display robust actin-based motility, vaccinia virus integrates the activity of the N-WASP– ARP2/3 and Rac1–FHOD1 pathways.

Thermodynamic model for process design, simulation and optimization in the production of biodiesel

Thermodynamic model for process design, simulation and optimization in the production of biodiesel Cotabarren, Natalia Soledad; Hegel, Pablo Ezequiel; Pereda, Selva The separation processes of the biodiesel production process require thermodynamic models able to correlate and predict the phase equilibria of mixtures at different stages of the process. Moreover, some units like those in the glycerol washing sector, require high accuracy due to their sensitivity to the components distribution coefficients. In this work, the Group Contribution Equation of State (GCA-EoS) is applied to model several systems of importance in this field. The mixtures evaluated can be highly non-ideal, especially in the last purification steps where polar compounds are infinitely diluted in biodiesel. Experimental VLE and LLE data were satisfactorily correlated and predicted with a single set of interaction parameters, using a simplified version of the association contribution of the model. In this way GCA-EoS can be used for the whole process with a faster convergence of simulated units in comparison with the case of considering the rigorous association model. Furthermore, considering that GCA-EoS is a group contribution model, biodiesel production from different raw material, i.e soy, palm or canola oil, can be predicted without requiring new parameters adjustment. The prediction model can be applied to the design, simulation and optimization of the production and purification sections.

Desde la investigación a la extensión en la construcción colectiva de políticas públicas en educación rural

Desde la investigación a la extensión en la construcción colectiva de políticas públicas en educación rural; From research to extension, in the collective construction of public policies in rural education Cragnolino, Elisa Rita; Delprato, María Fernanda; Brumat, María Rosa; Caciorgna, Laura; Ominetti, Laura María; Piccioni, Andrea La intención de este artículo es recuperar los procesos extensionistas desarrollados desde el Programa de Investigaciones “Educación en espacios sociales rurales y educación básica de jóvenes y adultos”, radicado en el Centro de Investigaciones María Saleme de Burnichon de la Facultad de Filosofía y Humanidades de la UNC. Nos referiremos en particular, al acompañamiento que estamos realizando al Movimiento Campesino de Córdoba (MCC) en la propuesta de construir escuelas de nivel medio para jóvenes y adultos del norte y noroeste de la provincia. El proyecto presentado al Ministerio de Educación, en forma conjunta con la Secretaría de Extensión Universitaria de la UNC, propone la creación de escuelas de nivel medio, de gestión pública, cogestionadas con las familias de las comunidades y con una modalidad de alternancia. La referencia a este proceso de acompañamiento al MCC nos permitirá abordar la manera en que fuimos construyendo la relación entre investigación-extensión y las perspectivas teóricas y metodológicas desde las que trabajamos. Recuperaremos el camino que hicimos, y que aún estamos recorriendo, en la propuesta de construir espacios educativos alternativos para las familias campesinas. En esta construcción intentamos ser coherentes con una manera de entender a la educación, a las responsabilidades del Estado, al lugar de la universidad pública y al modo en que consideramos a las políticas educativas y la posibilidad de construirlas colectivamente.; The purpose of this article is to recover the extension processes developed from the Research Program: “Education in Rural Social Environments and Basic Education for Young People and Adults”, based on the María Saleme de Burnichon Research Center of the School of Philosophy and Humanities, at the National University of Cordoba. We specifically refer to our support of the Movimiento Campesino de Córdoba (MCC) [Cordoba Peasant Movement] in the proposal to build mid-level schools for young people and adults from the North and Northwest of the province. The project submitted to the Ministry of Education, together with the Secretary for the University Extension Program of the UNC, proposes the creation of state-run mid-level schools, co-managed by the families in the community on a rotational basis. Referring to this process to support the MCC will allow us to approach the manner in which we built the relationship between research-extension, and the theoretical and methodological perspectives we applied in our work. We will recover the path we built, and that we are still travelling, in the proposal to build alternative educational areas for the peasant families. In this construction, we will try to be coherent with a way of understanding education, the State’s responsibilities, the public university’s place, and the manner in which we consider educational policies, as well as the possibility of building them collectively.

Genome Sequence of the Melanin-Producing Extremophile Aeromonas salmonicida subsp. pectinolytica Strain 34melT

Genome Sequence of the Melanin-Producing Extremophile Aeromonas salmonicida subsp. pectinolytica Strain 34melT Pavan, María Elisa; Pavan, Esteban E.; López, Nancy Irene; Levin, Laura Noemí; Pettinari, María Julia The genome of Aeromonas salmonicida subsp. pectinolytica strain 34melT, isolated from a heavily polluted river, contains several genomic islands and putative virulence genes. The identification of genes involved in resistance to different kinds of stress sheds light on the mechanisms used by this strain to thrive in an extreme environment.

Progressive external ophthalmoplegia (PEO) due to a mutation in the C10orf2 (PEO1) gene mimicking a myasthenic crisis

Progressive external ophthalmoplegia (PEO) due to a mutation in the C10orf2 (PEO1) gene mimicking a myasthenic crisis Gonzalez Moron, Dolores; Bueri, José; Kauffman, Marcelo Andres We described a case of a patient with autosomal dominant progressive external ophthalmoplegia (PEO) who presented with the acute onset dysphagia, quadriparesis, ptosis and respiratory insufficiency following a cardiac procedure and mimicking a myasthenic crisis. A pathogenic mutation in the C10orf2 (PEO1) gene was confirmed. The unusual presentation of our patient contributes to expand the clinical phenotype of PEO1 mutations and reinforces the need to consider mitochondrial myopathy as differential diagnosis of myasthenia gravis even in the case of acute onset symptoms.

Una mappa stellare per l'America latina: 3 'D' per orientare il consolidamento di processi imprescindibili

Una mappa stellare per l'America latina: 3 'D' per orientare il consolidamento di processi imprescindibili Marcionni, Nelson Daniel La dinámica interna de los actuales procesos de integración en América Latina puede valorarse sólo en un marco estrictamente contextualizado, situado, de reflexión crítica, sólida y profunda, sobre aspectos trascendentes y cuestiones jurídicas relevantes directamente asociadas a las posibilidades de un mayor bienestar en el disfrute de los derechos, no ya sobre la base del ejercicio del derecho al desarrollo, sino desde la concepción mucho mayor de Desarrollo Humano que subyace en el imaginario de la integración latinoamericana,  y que requiere un planteo que debiera contribuir a descolonizar la visión supuestamente paradigmática del proceso de integración europeo; a revalorizar para la vida en democracia y en el Estado de Derecho de los países latinoamericanos, los alcances de una mejor, más genuina y auténtica construcción teórica sobre los procesos de integración regional y, con ello,  a respetar, por contextualizada, sus lineamientos propios que los alejan sin duda, de proyectos que excluyentemente persigan sólo optimizar la dimensión y eficiencia de los mercados.   Con esos objetivos, aunque hacia Nuestro Sur, las prioridades estratégicas de descolonizar, democratizar y desmercantilizar, tanto en su enunciación y alcance originales propuestos por De Sousa Santos, como en los que nos permitimos recrear para un enfoque específico sobre los procesos de integración desde una perspectiva comparada,  guardan vigencia y definen un rumbo necesario para las decisiones y las acciones, tanto en el terreno político cuanto en el de la labor intelectual.

Josefina Ludmer y el libro que se transformó en clase

Josefina Ludmer y el libro que se transformó en clase Gerbaudo, Analía Isabel Esta presentación gira sobre la relación entre clases y publicaciones en el trabajo intelectual de Josefina Ludmer. Se centra para ello en un episodio: el de un libro imaginado que finalmente convierte en cursos y seminarios. El artículo analiza esta decisión en el marco de sus fantasías de nano-intervención: desde este lugar se infieren las continuidades que articulan sus variaciones metodológicas.

Nitric oxide and AQP2 in hypothyroid rats: A link between aging and water homeostasis

Nitric oxide and AQP2 in hypothyroid rats: A link between aging and water homeostasis Sarati, Lorena Ivonne; Toblli, Jorge Eduardo; Martinez, Carla Romina; Uceda, Ana Margarita; Feldman, Mariana Laura; Balaszczuk, Ana Maria; Fellet, Andrea L. Objective Hypothyroid state and aging are associated with impairment in water reabsorption and changes in aquaporin water channel type 2 (AQP2). Nitric oxide (NO) is involved in AQP2 trafficking to the apical plasma membrane in medullary collecting duct cells. The purpose of this study was to investigate whether aging and hypothyroidism alter renal function, and whether medullary NO and AQP2 are implicated in maintaining water homeostasis. Materials/Methods Sprague-Dawley rats aged 2 and 18 months old were treated with 0.02% methimazole (w/v) during 28 days. Renal function was examined and NO synthase (NOS) activity ([14C (U)]-L-arginine to [14C (U)]-L-citrulline assays), NOS, caveolin-1 and -3 and AQP2 protein levels were determined in medullary tissue (Western blot). Plasma membrane fraction and intracellular vesicle fraction of AQP2 were evaluated by Western blot and immunohistochemistry. Results A divergent response was observed in hypothyroid rats: while young rats exhibited polyuria with decreased medullary NOS activity, adult rats exhibited a decrease in urine output with increased NOS activity. AQP2 was increased with hypothyroidism, but while young rats exhibited increased AQP2 in plasma membrane, adult rats did so in the cytosolic site. Conclusions Hypothyroidism contributes in a differential way to aging-induced changes in renal function, and medullary NO and AQP2 would be implicated in maintaining water homeostasis.

Activation of presynaptic GABA b(1a,2) receptors inhibits synaptic transmission at mammalian inhibitory cholinergic olivocochlear-hair cell synapses

Activation of presynaptic GABA b(1a,2) receptors inhibits synaptic transmission at mammalian inhibitory cholinergic olivocochlear-hair cell synapses Wedemeyer, Carolina; Zorrilla de San Martín, Javier; Ballestero, Jimena Andrea; Gomez Casati, Maria Eugenia; Torbidoni, Ana Vanesa; Fuchs, Paul A.; Bettler, Bernhard; Elgoyhen, Ana Belen; Katz, Eleonora The synapse between olivocochlear (OC) neurons and cochlear mechanosensory hair cells is cholinergic, fast, and inhibitory. The inhibitory sign of this cholinergic synapse is accounted for by the activation of Ca 2+ -permeable postsynaptic α9α10 nicotinic receptors coupled to the opening of hyperpolarizing Ca 2+ -activated small-conductance type 2 (SK2)K + channels. Acetylcholine (ACh) release at this synapse is supported by both P/Q- and N-type voltage-gated calcium channels (VGCCs). Although the OC synapse is cholinergic, an abundantOCGABAinnervation is present along themammaliancochlea. The role of this neurotransmitter at theOCefferent innervation, however, is for the most part unknown.Weshow thatGABAfails to evoke fast postsynaptic inhibitory currents in apical developing inner and outer hair cells. However, electrical stimulation ofOCefferent fibers activates presynapticGABA B(1a,2) receptors [GABAB (1a,2) Rs] that downregulate the amount of ACh released at the OC-hair cell synapse, by inhibiting P/Q-type VGCCs. We confirmed the expression of GABA B Rs at OC terminals contacting the hair cells by coimmunostaining for GFP and synaptophysin in transgenic mice expressing GABA B1 -GFP fusion proteins. Moreover, coimmunostaining with antibodies against the GABA synthetic enzyme glutamic acid decarboxylase and synaptophysin support the idea that GABA is directly synthesized at OC terminals contacting the hair cells during development. Thus, we demonstrate for the first time a physiological role for GABA in cochlear synaptic function. In addition, our data suggest that the GABA B1a isoform selectively inhibits release at efferent cholinergic synapses.

Variación temporal en abundancia de huevos y larvas de Engraulis anchoita en el litoral nortpatagónico de enero a abril de 2001: crecimiento y mortalidad larval

Variación temporal en abundancia de huevos y larvas de Engraulis anchoita en el litoral nortpatagónico de enero a abril de 2001: crecimiento y mortalidad larval; Temporal variation in Engraulis anchoita eggs and larvae abundance in the northpatagonian littoral between January-April 2001. Larval growth and mortality Brown, Daniel Roberto; Leonarduzzi, Ezequiel; Averbuj, Andres; Livore, Juan Pablo Se analizaron los patrones de distribución y abundancia de huevos y larvas de anchoíta en el litoral norpatagónico argentino durante el período comprendido entre enero y abril de 2001. A medida que avanzaba la temporada se observó un proceso de disminución en la actividad reproductiva. Se establecieron las tasas de crecimiento y mortalidad de larvas. Las determinaciones de edad se realizaron analizando los incrementos diarios de otolitos. El valor promedio de la tasa de crecimiento de 0,43 mm día -1 no mostró diferencias espacio-temporales, hecho que se atribuyó a la homo- geneidad del campo térmico. La tasa de mortalidad natural, de 0,32 d -1 en enero, se determinó por extinción expo- nencial. Las tasas de mortalidad, estimadas con el modelo de mortalidad-agregación, se consideraron dependientes de la talla larval. Los rangos de valores (d -1 ) fueron 0,07-0,49, 0,05-0,61 y 0,07-0,51 para enero, febrero, y marzo-abril, respectivamente.; Argentine anchovy eggs and larvae abundance distribution patterns in the Argentine northpatagonian littoral during January-April 2001 were analyzed. As the season progressed, a process of decline in the reproductive activity was observed. Larval growth and mortality rates were established. Age determinations were performed analyzing otoliths daily increments. The 0.43 mm day -1 growth rate average did not show space-time differences, fact attributed to the homogeneity of the thermal field. The 0.32 d-1 January natural mor- tality rate was determined by exponential decline. Mortality rates, estimated with the mortality-aggregation model, were considered dependent on the larval size. The value ranges (d -1) were 0.07-0.49, 0.05-0.61 and 0.07-0.51 for January, February, and March-April, respectively.

A Reply to Palmira

A Reply to Palmira Lo Guercio, Nicolás Francisco In “Philosophical Peer Disagreement” I argued that in order to properly account for the phenomenon of philosophical peer disagreement it is necessary to drop the ‘same evidence’ condition from the definition of epistemic peerage. The reason is the following: different philosophical perspectives might come with different commitments concerning the evidential role of the same piece of data, and it would be wrong to deny the status of epistemic peer to someone that is acquainted with the same data, even if he does not consider it plays an evidential role. However, on “On the Necessity of the Evidential Equality Condition For Epistemic Peerage,” Michele Palmira has developed some criticisms to these ideas. Here I defend my view from Palmira’s objections.

La sanción de la capacidad civil plena de la mujer en los países del Cono Sur (1945-1990): una propuesta de análisis del fenómeno legal

La sanción de la capacidad civil plena de la mujer en los países del Cono Sur (1945-1990): una propuesta de análisis del fenómeno legal Giordano, Veronica En los primeros códigos civiles, las mujeres fueron definidas como sujetos de incapacidad de hecho relativa, limitación que venía asociada a la potestad del varón dentro del matrimonio. Este artículo aborda el reconocimiento de la capacidad civil plena de las mujeres en Uruguay (1946), Brasil (1962), Argentina (1968) y Chile (1989) como parte de un proceso complejo hacia la erosión (pero no disolución) del patriarcado. Para ello pone en práctica una metodología específica para el análisis del fenómeno legal que permite revelar los mecanismos discriminatorios. Asimismo, asume una perspectiva sociológico-histórica comparativa que muestra los diferentes recorridos hacia la reforma de la ley civil y los elementos que le son comunes. Se explicitan las distintas trayectorias, asumiendo que las dinámicas internas son únicas, pero mostrando que es posible identificar un mismo patrón de cambio: la modernización conservadora. En efecto, las mujeres casadas quedaron fijadas como sujetos de inferioridad jurídica, incluso cuando se les otorgó formalmente la capacidad civil plena. La modernización trajo cambios, pero el proceso estuvo dominado por las fuerzas de la tradición.

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