Disputas jurídico – políticas en torno a las expropiaciones de inmuebles rurales en la provincia de Chaco; Legal and political disputes over the expropriation of rural lands in the province of Chaco Barbetta, Pablo Nicolas Las organizaciones campesinas y de pequeños productores así como también indígenas despliegan una serie de acciones y estrategias, tanto judiciales como político administrativas, para frenar los procesos de exclusión por los que atraviesan como consecuencia de los procesos desatados por la hegemonía del modelo del agronegocio. En la provincia de Chaco, este activismo se reflejó en el resurgimiento, luego del proceso liguista, de múltiples organizaciones campesinas y de pequeños productores e indígenas, con el consecuente el despliegue de acciones de protesta y de resistencia. En este contexto de acorralamiento y expulsión de los pequeños productores y/o campesinos de la tierra es que nos interrogamos acerca de la expropiación como estrategia para lograr el acceso a la propiedad de la tierra. Así, el objetivo generalde este trabajo remite a analizar y comprender los procesos de expropiación de tierras, en tanto acción político –jurídica, para lograr el acceso a la propiedad de la tierra o su titularidad por parte de pequeños productores campesinos e indígenas en la provincia de Chaco.; The peasant and of small producers well as also indigenous organizations deploy a series of actions and strategies, both judicial and administrative political, to curb the processes of exclusion by those who traverse as consequence of the processes untied for hegemony model of agribusiness. In the province of Chaco, this activism was reflected in the resurgence, after the liguista process, of multiple peasant organizations and of small producers e indigenous, with the consequent the deployment of protest actions and of resistance. In this context of encirclement and expulsion of small producers and / or peasants of land is where I’m looking of expropriation as strategy to achieve access to land ownership. Well, the overall objective of this work refers to analyze and understand the processes land expropriation, in both –juridical and political action, to achieve access to land ownership or their ownership by small producers, peasants e indigenous in the province of Chaco.

La acreditación regional de la calidad universitaria en cuestión: ¿modelos en tensión en América del Sur? Perrotta, Daniela Vanesa Este artículo se centra en el análisis de la política regional de acreditación universitaria del Mercado Común del Sur (MERCOSUR) en vistas a, primero, indagar cómo la política regional se ha difundido a la arena de política interna, generando impactos políticos y cambios institucionales en los Estados Parte (regionalismo regulatorio); y segundo, discutir la orientación de esta política regional.El trabajo se divide en tres secciones: primero, un breve apartado que describe la política de acreditación de la calidad (AC) del MERCOSUR; segundo, una sección analítica en dos niveles: los procesos de articulación y difusión de políticas entre la región y el ámbito doméstico y la identificación de modelos alternativos de AC en el MERCOSUR; tercero, una discusión final sobre el armado de criterios regionales de calidad y procedimientos de evaluación universitaria.

Gestos técnicos, morfología y rastros de uso en la alfarería prehispánica del sitio La Palmera 2 (provincia de Entre Ríos) Ottalagano, Flavia Vanina; Brancatelli, Carolina; Darigo, Mariano Héctor; Iannelli, Lucía; Pereyra, Belén Este artículo presenta y discute los resultados preliminares obtenidos del estudio de los materiales cerámicos recuperados en el sitio arqueológico La Palmera 2, localizado en el Paraná medio (Departamento Paraná, provincia de Entre Ríos, nordeste de Argentina). Este sitio fue ocupado por grupos cazadores-recolectores complejos en torno al 1056-1032 + 47 AP. Se tienen en cuenta atributos relacionados con los aspectos formales, funcionales y técnicos de las vasijas, cuyo análisis permite avanzar hacia el estudio de la tecnología cerámica de un sector del río Paraná que todavía cuenta con un corpus de datos arqueológicos y una trayectoria de investigación relativamente escasa.; This paper presents and discusses the preliminary results obtained of the study of ceramic materials recovered from the archaeological site La Palmera 2, located in the middle Paraná (department of Paraná, province of Entre Ríos, northeast of Argentina).This site was occupied by complex hunter-gatherer groups around 1056-1032 + 47 b.p. Characteristics related to techno-morphological and functional aspects of the vessels have been taken into account, and these analyses have allowed advancements in the study of ceramic technology from an area of the Paraná River that still possesses a relatively scarce body of data and research work.

Organic Anion Transporter 5 (Oat5) Urinary Excretion Is a Specific Biomarker of Kidney Injury: Evaluation of Urinary Excretion of Exosomal Oat5 after N-Acetylcysteine Prevention of Cisplatin Induced Nephrotoxicity Bulacio, Romina Paula; Anzai, Naohiko; Ouchi, Motoshi; Torres, Adriana Monica Cisplatin is a commonly used chemotherapeutic agent. Its main side-effect is nephrotoxicity. It was reported that the organic anion transporter 5 (Oat5) urinary excretion is elevated, implying renal perturbation, when no modifications of traditional markers of renal damage are still observed in cisplatin-induced acute kidney injury (AKI). It was also demonstrated that Oat5 is excreted in urine by the exosomal pathway. This study was designated to demonstrate the specific response of the urinary excretion of exosomal Oat5 to kidney injury independently of other cisplatin toxic effects, in order to strengthen Oat5 urinary levels as a specific biomarker of AKI. To accomplish that aim, we evaluated if urinary excretion of exosomal Oat5 returns to its basal levels when cisplatin renal damage is prevented by the coadministration of the renoprotective compound N-acetylcysteine. Four days after cisplatin administration, AKI was induced in cisplatin-treated male Wistar rats (Cis group), as it was corroborated by increased urea and creatinine plasma levels. Tubular damage was also observed. In cotreated animals (Cis + NAC group), plasma urea and creatinine concentrations tended to return to their basal values, and tubular damage was improved. Urinary excretion of exosomal Oat5 was notably increased in the Cis group, but when renal injury was ameliorated by N-acetylcysteine coadministration, that increase was undetected. So, in this work we observed that urinary excretion of exosomal Oat5 was only increased if renal insult is produced, demonstrating its specificity as a renal injury biomarker. (Chemical Equation Presented).

Cine, tecnologías del erotismo y homosexualidades masculinas en Argentina Blazquez, Gustavo Este trabajo analiza los modos de amar entre varones, es decir modelos que permiten imaginar y experimentar las relaciones (homo)afectivas y las caricias entre hombres, a partir de la lectura de una serie de films argentinos. Específicamente nos interesa describir y comparar imágenes elaboradas en tres momentos históricos. En primer lugar nos detendremos en Extraña ternura, dirigido por Daniel Tinayre en 1964. Posteriormente será el turno de dos producciones de la década de 1980: Adiós Roberto (1985) de Enrique Dawi y Otra historia de amor (1986) de Américo Ortiz de Zárate. Por último, consideraremos El tercero de Rodrigo Guerrero estrenada en 2014 ya en los años de legalización del matrimonio civil entre sujetos del mismo sexo. Para acercarnos a estos textos visuales nos valemos de las nociones de «tecnologías del género» propuesta por Teresa de Lauretis y «guiones sexuales» elaborada por Gagnon y Simon (1974) en sus estudios sobre la conducta sexual. La lectura de las obras no se interesa exclusivamente por el texto visual y sonoro sino que atiende también diferentes indicios extradiegéticos y a la recepción del film a partir de datos construidos en un trabajo de campo junto con varones homosexuales en la ciudad de Córdoba.; This paper analyzes the ways of love between men, the models to imagine and experience (homo) affective relationships and caresses between men, from a reading of a number of Argentine films. Specifically we want to describe and compare images drawn in three historical moments. First we stop at Extraña ternura, directed by Daniel Tinayre in 1964. It will then be the turn of two productions of the 1980s: Adios Roberto (1985) by Enrique Dawi and Otra Historia de Amor (1986) of Américo Ortiz de Zárate. Finally, we consider El tercero by Rodrigo Guerrero released in 2014 in the years of legalization of civil marriage between same-sex individuals. To approach these visual texts we use the notions of «gender technology» proposed by Teresa de Lauretis and «sexual scripts» developed by Gagnon and Simon in the studies on sexual behavior. The reading of the works is not interested solely by visual and audible text but also serves extradiegetic different signs and the reception of the film from data constructed in an ethnography with gay men in the city of Cordoba.

Discapacidad y mendicidad en la era de la Convención: ¿postal del pasado?; Disability and begging in the era of the Convention: a postcard from the past? Ferrante, Carolina En este trabajo se comparten los resultados de una investigación cualitativa que analizó los procesos sociales que conducen al ejercicio de la mendicidad en varones con discapacidad de la Ciudad de Buenos Aires, con la intención de problematizar el diagnóstico que afirma un cambio en las actitudes hacia esta minoría, a partir de la Convención Internacional sobre los Derechos de las Personas con Discapacidad. Al recuperar críticamente el modelo social de la discapacidad, se identifican cuatro itinerarios asociados a nuevas formas de vulnerabilidad promovidas por el capitalismo actual en contextos periféricos (pérdida del empleo, debilitamiento de redes, desempleo crónico y naturalización de la discapacidad como tragedia médica individual) que configuran las condiciones de posibilidad de esta postal. Se concluye que estos procesos evidencian la existencia de políticas de discapacitación y mecanismos de soportabilidad eregidos para sobrevivir en un mundo desigual, expresando el problema de la "nueva cuestión social".; This paper shares the results of a qualitative study that examined the social processes that lead to the practice of begging in men with disabilities in the City of Buenos Aires, with the intention to problematize the diagnosis asserting a change in attitudes toward this minority from the International Convention on the Rights of Persons with Disabilities. Critically retrieving the social model of disability, we identified four routes associated with new forms of vulnerability promoted by today's capitalism in peripheral contexts (job loss, weakening of networks, chronic unemployment and naturalization of disability as an individual medical tragedy), which configure the possibility conditions of this postcard. We conclude that these processes show the existence of disability policies and supportability mechanisms erected to survive in an unequal world, expressing the problem of the "new social question".

El pinball proteico; The protein pinball Ferreiro, Diego; Sánchez Miguel, Ignacio Enrique

Photoinactivation of tyrosinase sensitized by folic acid photoproducts Dantola, Maria Laura; Zurbano, Beatriz Norma; 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 biomolecules, accumulate in the skin of patients suffering from vitiligo, where there is a lack of melanin. Folic acid (PteGlu) is a conjugated pterin widespread in biological systems. Aqueous solutions of tyrosinase were exposed to UV-A irradiation (350 nm) in the presence of PteGlu and its photoproducts (6-formylpterin and 6-carboxypterin). The reactions were followed by UV-Vis spectrophotometry, enzyme activity measurement, fluorescence spectroscopy and HPLC. In this work, we present data that demonstrate unequivocally that solutions of tyrosinase exposed to UV-A irradiation in the presence of PteGlu, undergo enzyme inactivation. However, PteGlu itself causes a negligible effect on the activity of the enzyme. In contrast, PteGlu photoproducts are efficient photosensitizers. The tyrosinase inactivation involves two different pathways: (i) a photosensitization process and (ii) the oxidation of the enzyme by the hydrogen peroxide produced during the photooxidation of PteGlu and its photoproduct. The former pathway affects both the active site and the tryptophan residues, whereas the latter affects only the active site. The biological implications of the results are discussed.

Improvement in imazalil treatments in commercial packinglines to control green mold on lemon fruit Sepúlveda, M.; Cuevas, I. I.; Smilanick, J. L.; Cerioni, Luciana; Rapisarda, Viviana Andrea; Ramallo, J. Long distance to markets limits global competitiveness in lemon fruit production due to fungal postharvest decays, such as green mold caused by Penicillium digitatum. Imazalil, the main fungicide used, is formulated as an emulsifiable concentrate (IEC) and as a water-soluble sulphate salt (IS), the later being less commonly applied in most of the producing countries. The aim of the present report was to improve the effectiveness of imazalil treatments to control green mold in commercial scale. In both laboratory and commercial applications, IS was more effective than IEC. IS formulation applied in water followed by IEC applied in wax is an improved option that provided suitable disease control and optimal residue loading >2.0 mg L−1 without exceeding the maximum residue levels. Additionally, IMZ residues remained at acceptable levels after 28 days at 7 °C, assuring the protection of lemon fruit for long periods of storage and transports.

Physical stress modifies top-down and bottom-up forcing on plant growth and reproduction in a coastal ecosystem Daleo, Pedro; Alberti, Juan; Bruschetti, Carlos Martin; Pascual, Jesus Maria; Iribarne, Oscar Osvaldo; Silliman, Brian Red Bottom-up and top-down effects act together to exert strong control over plant growth and reproduction, but how physical stress modifies those interactive forces remains unclear. Even though empirical evidence is scarce, theory predicts that the importance of both top-down and bottom-up forces may decrease as physical stress increases. Here, we experimentally evaluate in the field the separate and interactive effect of salinity, nutrient availability, and crab herbivory on plant above- And belowground biomass, as well as on sexual and clonal reproduction in the salt marsh plant Spartina densiflora. Results show that the outcome of the interaction between nutrient availability and herbivory is highly context dependent, not only varying with the abiotic context (i.e., with or without increased salinity stress), but also with the dependent variable considered. Contrary to theoretical predictions, our results show that, consistently across different measured variables, salinity stress did not cancel bottom-up (i.e., nutrients) or top-down (i.e., consumers) control, but has additive effects. Our results support emerging theory by highlighting that, under many conditions, physical stress can act additively with, or even stimulate, consumer control, especially in cases where the physical stress is only experienced by basal levels of the trophic chain. Abiotic stress, as well as bottom-up and top-down factors, can affect salt marsh structure and function not only by affecting biomass production but also by having other indirect effects, such as changing patterns in plant biomass allocation and reproduction.

Sauropod and theropod dinosaur tracks from the Upper Cretaceous ofMendoza (Argentina): Trackmakers and anatomical evidences Gonzalez Riga, Bernardo Javier; Ortiz David, Leonardo Daniel; Tomaselli, María Belén; dos Anjos Candeiro, Carlos Roberto; Coria, Juan Pedro; Pramparo, Mercedes Beatriz New findings of dinosaur ichnites from Agua del Choique section (Mendoza Province, Argentina) provides ichnological and anatomical information about the Cretaceous sauropods and theropods. Around 330 tracks distributed in six footprint levels were identified in this area, one of most important of South America. Two ichnocenoses are located in different paleoenvironmental contexts. In the Anacleto Formation (early Campanian) around 20 titanosaurian tracks were found in floodplain and ephemeral channel deposits. Herein, one pes track shows three claw impressions and this is congruent to two new titanosaur specimens recently discovered in Mendoza Province that have articulated and complete pedes. In this context, for the first time to titanosaurs, ichnological evidences are supported by skeletal elements. In the Loncoche Formation (late Campanian-early Maastrichtian) titanosaurian tracks of Titanopodus mendozensis are abundant (around 310 tracks) and were produced by titanosaurs that walked in a very wet substrate of tidally dominated deltas related with the first Atlantic transgression for northern Patagonia. In this facies association, three different trydactl tracks indicate the presence of small theropods (1-2m long), expanding the knowledge about the faunistic components that lived in these marine marginal environments.

The terpene ketones as natural insecticides against Sitophilus zeamais Herrera, Jimena María; Zunino, María Paula; Dambolena, José Sebastián; Pizzolitto, Romina Paola; Gañan, Nicolas Alberto; Lucini, Enrique Iván; Zygadlo, Julio Alberto The eleven terpene ketones, thymoquinone, (R)-carvone, (S)-carvone, pulegone, dihydrocarvone, menthone, verbenone, ocimenone, camphor, α-thujone and piperitenone, were tested as contact and fumigant insecticides against adults of Sitophilus zeamais Motschulsky under laboratory conditions. The results show that thymoquinone was found to be more toxic than the other ketones, with lethal doses values being LC50 16.5 μg/cm2 and LC50 13.8 μL/L air (24 h after treatment). These ketones were also subjected to multiple regression analysis and the results derived from the quantitative structure activity relationship (QSAR) model suggested two topological indicators, the Balaban and Randic indices, were the best descriptors of insecticidal activity of the ketones. However, orbital electronegativity of the carbonyl group was the main parameter that connected the inhibition activity of ketones on acetylcholinesterase (AChE). Thus, the insecticidal activity of terpene ketones was primarily explained by the shape of molecules and the branching of the carbon-atom skeleton, while inhibition of activity of AChE was mainly due to the electronic descriptors.

Validation Strategies for Satellite-Based Soil Moisture Products Over Argentine Pampas Grings, Francisco Matias; Bruscantini, Cintia Alicia; Smucler, Ezequiel; Carballo, Federico; Dillon, María Eugenia; Collini, Estela Angela; Salvia, Maria Mercedes; Karszenbaum, Haydee In this paper, an evaluation strategy for twocandidate satellite-derived SM products is presented. In particular, we analyze the performance of two candidate algorithms [soil moisture ocean salinity (SMOS)-based soil moisture (SM) and advanced scatterometer (ASCAT)-based SM] to monitor SM in Pampas Plain. The difficulties associated with commonly used evaluation techniques are addressed, and techniques that do not require ground-based observations are presented. In particular, we introduce comparisons with a land-surface model (GLDAS) and SM anomalies and triple collocation analyses. Then, we discuss the relevance of these analyses in the context of end-users requirements, and propose an extreme events-detection analysis based on anomalies of the standardized precipitation index (SPI) and satellite-based SM anomalies. The results show that: 1) both ASCAT and SMOS spatial anomalies data are able to reproduce the expected SM spatial patterns of the area; 2) both ASCAT and SMOS temporal anomalies are able to follow the measured in situ SM temporal anomalies; and 3) both products were able to monitor large SPI extremes at specific vegetation conditions.

Enzyme-catalyzed preparation of chenodeoxycholic esters by an immobilized heterologous Rhizopus oryzae lipase Quintana, Paula Gabriela; Canet, Albert; Marciello, Marzia; Valero, Francisco; Palomo, José M.; Baldessari, Alicia A lipase-catalyzed preparation of ethyl and stearyl esters of chenodeoxycholic acid is described. Stearyl chenodeoxycholate is a new product and both bile acid esters were prepared through an enzymatic approach for the first time. The heterologous Rhizopus oryzae lipase, immobilized on two different supports proved to be an efficient catalyst, even more active than Candida antarctica lipase, in the esterification reaction using a complex substrate such as a bile acid. The immobilization of the enzyme on Octadecyl Sepabeads at pH 7 and 25 °C was the best choice to catalyze the esterification reaction. The influence of various reaction parameters, such as nature of the alcohol, alcohol:substrate ratio, enzyme:substrate ratio, solvent and temperature, was evaluated. Using the response surface methodology and a central composite rotatable design, the conversion of stearyl chenodeoxycholate was optimized by means of the study of the effect of enzyme:substrate ratio and alcohol:substrate ratio. The value 20 for ratios (E/S) and (A/S) was predicted as the optimal value to reach the maximum conversion. However, including economic aspects these ratios can be reduced up to 15. The well-known advantages of biocatalysis and the activity shown by the immobilized heterologous lipase make the reported procedure a convenient way to prepare chenodeoxycholic esters.

Preventive anti-inflammatory activity of an aqueous extract of larrea divaricata cav. and digestive and hematological toxicity Davicino, Roberto Carlos; Peralta, Ignacio Nahuel; Martino, Renzo Fabricio; Alonso, Rosario; Anesini, Claudia Alejandra Larrea divaricata Cav. commonly known as “jarilla hembra” is used in folklore medicine as anti-inflammatory. There was no scientific evidence justifying the medicinal use of the aqueous extract for inflammation diseases. Nowadays, there are two principal types of anti-inflammatory drugs: Steroidal anti-inflammatory drugs (corticosteroids) and non-steroidal anti-inflammatory drugs (NSAIDs), which exert gastrointestinal ulceration and bleeding. In this work the preventive anti-inflammatory activity of L. divaricata aqueous extract (AE) in C3H/He mice was determined by carrageenan- induced inflammation and ear edema tests, also its toxicity on gastric tissues and on blood cells was studied. The chromatographic profile showed: nordihydroguaiaretic acid (NDGA) as majority compound. AE exerted anti-inflammatory action without inducing gastric or blood cell toxicities. Also, it could modulate anti-inflammatory and pro-inflammatory cytokines. NDGA was not the compound responsible of the anti-inflammatory action. This work rescues the potentiality of AE as a gastric and blood cells innocuous anti-inflammatory agent and confirms its ethno- pharmacological uses.

Impacto ambiental de los remanentes de supernova Dubner, Gloria Mabel The explosion of a supernovae (SN) represents the sudden injection of about 10^51 ergs of thermal and mechanical energy in a small region of space, causing the formation of powerful shock waves that propagate through the interstellar medium at speeds of several thousands of km/s. These waves sweep, compress and heat the interstellar material that they encounter, forming the supernova remnants. Their evolution over thousands of years change forever, irreversibly, not only the physical but also the chemical properties of a vast region of space that can span hundreds of parsecs. This contribution briefly analyzes the impact of these explosions, discussing the relevance of some phenomena usually associated with SNe and their remnants in the light of recent theoreticaland observational results.

Migration of titanium dioxide microparticles and nanoparticles through the body and deposition in the gingiva: an experimental study in rats Guglielmotti, Maria Beatriz; Domingo, Mariela G.; Steimetz, Tammy; Ramos, Emilio; Paparella, María L.; Olmedo, Daniel Gustavo The aim of this experimental work was to evaluate deposition of titanium dioxide (TiO2) microparticles and nanoparticles, which could originate from titanium bioimplants, in the gingiva. Wistar rats were injected intraperitoneally (i.p.) with a suspension of TiO2 particles of different sizes (150, 10, or 5 nm). The rats were killed 12 months post-injection, and the buccal and lingual gingivae were resected and evaluated using light and scanning electron microscopy. Energy-dispersive X-ray spectroscopy (EDS) was used to confirm the presence of titanium in deposits of microparticles and nanoparticles, and the concentration of titanium in tissues was measured using inductively coupled plasma–mass spectrometry (ICP-MS). Histological examination showed that all experimental groups exhibited agglomerates, in the gingiva, of titanium particles of micrometer size range, with no associated inflammatory response. Higher concentrations of titanium traces were shown, by ICP-MS, in both buccal and lingual tissues of all experimental groups compared with their matched controls. Titanium concentrations were significantly higher in the buccal gingiva than in the lingual gingiva, and after injection with 5-nm particles than with 10-nm particles in both localizations. Titanium microparticles and nanoparticles deposit in the gingiva, and mostly on the buccal side. Gingival deposition of titanium could be considered a tissue indicator of tribocorrosion processes of titanium bioimplants.

Melanocortin 4 receptor activates ERK-cFos pathway to increase brain-derived neurotrophic factor expression in rat astrocytes and hypothalamus Ramírez, Delia; Saba, Julieta; Carniglia, Lila; Durand, Daniela Elizabeth; Lasaga, Mercedes Isabel; Caruso, Carla Mariana Melanocortins are neuropeptides with well recognized anti-inflammatory and anti-apoptotic effects in the brain. Of the five melanocortin receptors (MCR), MC4R is abundantly expressed in the brain and is the only MCR present in astrocytes. We have previously shown that MC4R activation by the α-melanocyte stimulating hormone (α-MSH) analog, NDP-MSH, increased brain-derived neurotrophic factor (BDNF) expression through the classic cAMP–Protein kinase A–cAMP responsive element binding protein pathway in rat astrocytes. Now, we examined the participation of the mitogen activated protein kinases pathway in MC4R signaling. Rat cultured astrocytes treated with NDP-MSH 1 µM for 1 h showed increased BDNF expression. Inhibition of extracellular signal-regulated kinase (ERK) and ribosomal p90 S6 kinase (RSK), an ERK substrate, but not of p38 or JNK, prevented the increase in BDNF expression induced by NDP-MSH. Activation of MC4R increased cFos expression, a target of both ERK and RSK. ERK activation by MC4R involves cAMP, phosphoinositide-3 kinase (PI3K) and the non receptor tyrosine kinase, Src. Both PI3K and Src inhibition abolished NDP-MSH-induced BDNF expression. Moreover, we found that intraperitoneal injection of α-MSH induces BDNF and MC4R expression and activates ERK and cFos in male rat hypothalamus. Our results show for the first time that MC4R-induced BDNF expression in astrocytes involves ERK-RSK-cFos pathway which is dependent on PI3K and Src, and that melanocortins induce BDNF expression and ERK-cFos activation in rat hypothalamus.

Las formas asociativas de la agricultura familiar en el desarrollo rural argentino de las últimas décadas (1990-2014); Les formes associatives de l’agriculture familiale dans le développement rural argentin des dernières décennies (1990-2014); Types of family farm association in the rural development of Argentina in recent decades (1990-2014) Lattuada, Mario Jose; Nogueira, Maria Elena; Urcola, Marcos Andres El asociativismo en el medio rural ha sido destacado históricamente como un factor que contribuyó al desarrollo de los pequeños y medianos productores agropecuarios. Desde la década de 1990 hasta la actualidad se observa una intensificación del pluralismo asociativo argentino en favor de los sectores de la agricultura familiar, con el surgimiento de cientos de nuevas asociaciones autogeneradas o promovidas por programas de desarrollo rural públicos y privados, y que a pesar de caracterizarse por la actividad cooperativa de sus integrantes no han adoptado esa forma jurídica tradicional. El objetivo de este trabajo consiste en delimitar una serie de nociones que permitan delimitar ese vasto y diversificado universo de asociaciones que identificamos como Asociaciones Económicas de la Agricultura Familiar (AEAF), construyendo, para ello, una serie de tipos ideales con el fin de proponer una herramienta para el abordaje empírico de su estudio en diferentes realidades locales, nacionales y regionales.; Les associations dans le milieu rural se sont imposées historiquement comme facteur ayant contribué au développement des petits et moyens agriculteurs et éleveurs. Depuis les années 1990 jusqu’à aujourd’hui, on observe une intensification du pluralisme associatif argentin en faveur des secteurs de l’agriculture familiale, avec l’apparition de centaines de nouvelles associations autogénérées ou promues par des programmes de développement rural publics et privés, qui, même si elles sont caractérisées par l’activité coopérative de leurs membres, n’ont pas adopté cette forme juridique traditionnelle. Ce travail vise à déterminer une série de notions permettant de délimiter ce vaste et divers milieu d’associations identifiées comme Associations Économiques de l’Agriculture Familiale (AEAF), en établissant, pour cela, une série de types idéaux pour proposer un outil d’analyse empirique de leur étude sur différentes réalités locales, nationales et régionales.; Associations in rural areas have traditionally been pointed to as a factor that contributes to the development of small and medium-sized farming. From 1990 to the present, the number of associations in Argentina has multiplied among family farms. Hundreds of new associative partnerships have emerged, self-generated or promoted by public or private rural development programs, but although they are characterized by the cooperative activity of their members, they have not adopted this traditional legal form. The objective of this paper is to outline a set of notions that define the vast and diverse universe of associations identified as Economic Associations of Family Farms (AEAF) by constructing a series of ideal types, in order to propose a tool for an empirical approach to their study in different local, national and regional situations.

Brain acetylcholine and choline concentrations and dynamics in a murine model of the Fragile X syndrome: age, sex and region-specific changes Scremin, Oscar Umberto; Roch, M.; Norman, K.; Djazayeri, S.; Liu, Y. Y. Fragile X syndrome is a learning disability caused by excess of CGG repeats in the 5′ untranslated region of the Fragile X gene (FMR1) silencing its transcription and translation. We used a murine model of this condition, Fmr1 knock-out mice (KO) to study acetylcholine (ACh) metabolism and compared it to that of wild-type control mice (WT). Brain endogenous ACh (D0ACh), free choline (D0Ch), their deuterated variants D4ACh and D4Ch and mole ratios (AChMR and ChMR) were measured by gas chromatography–mass spectrometry in the cerebral hemisphere, cerebral cortex, hippocampus and cerebellum, following D4Ch administration. Regression analysis indicated a significant decrease with age (negative slope) of D4ACh, AChMR, D4Ch and ChMR in WT mice. Age dependence was only present for D4ACh and AChMR in KO mice. Analysis of variance with age as covariate indicated a significant greater D4Ch in the cerebral cortex of KO females when compared to WT females. Contrasts between sexes within genotypes indicated lower D0Ch in cortex and cerebellum of female KO mice but not in WT and lower D4Ch in hippocampus of female KO and WT mice. In conclusion, after adjusting for age, D0ACh concentrations and synthesis from deuterium-labeled Ch were similar in KO and control WT mice in all brain regions. In contrast, significant changes in Ch dynamics were found in hippocampus and cerebral cortex of KO mice that might contribute to the pathogenesis of FXS.