Presentación: "La internacional de los buenos sentimientos", de Louis Althusser Karczmarczyk, Pedro Diego Se trata de la presentación de la traducción de "Lai nternacional de los buenos sentimientos" el primer texto de Louis Althusser del que tengamos conocimiento (1946) que permaneció inédito hasta 1994. El texto es la intervención de un joven intelectual católico, ya en tránsito hacia el comunismo, frente al movimiento internacional promovido por diferentes intelectuales (Camus, Marcel, Mauriac, Malraux, Koestler y otros), conocido como "Frente humano", enfocado a enfrentar el riesgo de la aniquilación de la especie a través de la bomba atómica. La amenaza nuclear definiría así una condición existencial novedosa, verdaderamente universal, una suerte de "proletariado del miedo" construido por los nuevos "medios y relaciones de destrucción masiva". El escrito de Althusser devela en este movimiento, por un lado, la velada intención de promover un "socialismo sin lucha de clases" como barrera a la amenaza soviética. Pero lo más interesante es que Althusser consigue también cuestionar, en sus propios términos, la matriz presuntamente antitotalitaria que sustentalas posiciones del "Frente humano": la misma exigiría la posposición de todoreclamo sectorial debería ser pospuesto ya que las mismas sólo pueden tenerderivas totalitarias o apocalípticas. Reconociendo la matriz teológica de este discurso, Althusser desnuda que esta denuncia de los "falsos profetas" es en realidad herética, ya que se sustenta, sin reconocerlo, en una profecía sobre la inevitabilidad de la catástrofe que encubre que la misma no es un asunto del mañana, sino algo que está entre nosotros, desde anteayer. Su texto constituye, así, al decir de Montag, una crítica religiosa de la escatología. En nuestra presentación examinamos la concepción de la filosofía a lo largo dela oba de Althusser, recogemos la sugerencia de Warren Montag acerca de cómoeste texto sirve para cuestionar la ontologización del vacío presente en algunos escritos tardíos de Althusser y señalamos la vinculación de este texto con un campo ideológico constituido en Argentina en la época de la transición democrática (nos centramos en Carlos S. Nino y León Rozitchner), proseguido en una intensa polémica acaecida en el interior la izquierda argentina, el debate denominado "No matar", desatado por una carta del filósofo Oscar del Barco en 2004.

Increase in IS256 transposition in invasive vancomycin heteroresistant Staphylococcus aureus isolate belonging to ST100 and its derived VISA mutants Di Gregorio, Sabrina Noelia; Fernandez, Silvina; Perazzi, Beatriz Elizabeth; Bello, Natalia; Famiglietti, Angela María Rosa; Mollerach, Marta Eugenia In Staphylococcus aureus, transposition of IS256 has been described to play an important role in biofilm formation and antibiotic resistance. This study describes the molecular characterization of two clinical heterogeneous vancomycin-intermediate S. aureus (hVISA) isolates recovered from the same patient (before and after antibiotic treatment) and two VISA derivatives obtained by serial passages in the presence of vancomycin. Our results showed that antibiotic treatment (in vivo and in vitro) could enhance IS256 transposition, being responsible for the eventual loss of agr function. As far as we know this is the first study that reports the increase of IS256 transposition in isogenic strains after antibiotic treatment in a clinical setting.

Climate change and its impacts: Perception and adaptation in rural areas of Manizales, Colombia Barrucand, Mariana Graciela; Giraldo Vieira, Carolina; Canziani, Pablo Osvaldo Tropical social-ecological systems are highly vulnerable to climate change, given the limited natural climate variability in the tropics. Tropical rural populations, with livelihoods dependent on agriculture, are particularly vulnerable to climate variability and changes. To develop climate change social communication, plan and implement adaptation, it is necessary to understandregional/local climate process, risks and opportunities. It is also important to understand how local populations perceive such changes and adapt their livelihoods. Limited information is available on climate change perceptions in tropical Latin American rural populations. Hence, a climate study and climate change perception survey were carried out in the Manizales Municipality, in the Andean region of Colombia and one of its major coffee-growing areas. The study spanned three thermal levels in the tropical Andes, 1000 m a.s.l. and above, each with distinct environments and livelihoods. Climate analysis yielded significant warming trends in recent decades, particularly in temperature minima for all levels, but no significant local precipitation trends. The perception survey, carried out in a sparsely populated region, mostly withlimited accessibility, included 37 households, with structured and semi structured interviews, adapted to local culture. Interviewees had little or no previous knowledge on climate change. However, almost all had perceived significant changes in both temperature and precipitation, which impacted their livelihoods and environment. Some perceptions couldresult from a La Niña event prior to the survey, and other environmental destruction processes. Their responses to change were spontaneous adaptation, based on traditional practices and agricultural technical advice from state agencies and coffee grower associations.

Total reflection X ray fluorescence in environmental and geochemical studies: unveiling solute provenance in streams during a rain episode Rodríguez Castro, María Carolina; Vilches, Carolina; Torremorell, Ana María; Vázquez, Cristina; Giorgi, Adonis David Nazareno Rural population uses water for irrigation, animal watering and for their own consumption, therefore water contamination is a major concern and a priority for its inhabitants. Unveiling the presence and source of contaminants can help to understand the dynamic of pollutants and therefore define management politics to address the issue. One way to elucidate the origin of contaminants in surface water is by studying rain episodes, relating water discharge with changes in solute concentration. Total Reflection x-ray Fluorescence (TXRF) was used as the main analytical technique. The study was based on the analysis of samples originating from a Pampean stream (Buenos Aires, Argentina). Solutes (As, P, Ca, Fe, K, Zn, Br) were monitored before, during and after a storm event. During the monitoring it was observed that As was diluted at the beginning of the episode and concentration increased slowly after the rain ceased. The pattern of As is consistent with Ca, K and Fe behavior, revealing a groundwater source. Instead, P concentration increased in the early hours, it was diluted later and finally increased. This behavior indicates that the source of this analyte is superficial and sub superficial water, implying a runoff origin. The simultaneous determination of these analytes by TXRF allowed comparing solute behavior under the same episode, allowing reveal their provenance.

Soberanía y resistencia en el joven Fichte Damiani, Alberto Mario El propósito de este trabajo es explicar la conexión y la diferencia entre los derechos de soberanía y resistencia en la filosofía política de Fichte. El trabajo comienza con una investigación sobre la idea de soberanía en la Grundlage des Naturrechts. Luego es presentado el derecho de soberanía en el marco del la teoría del contrato social de Fichte. Por último, discuto las interpretaciones sobre estos tópicos de Ingeborg Maus y Jean-Christophe Merle.; The aim of this paper is to explain the connection and the difference between the rights of sovereignty and resistance in Fichte’s political philosophy. The paper begins with an investigation about the idea of sovereignty in the Grundlage des Naturrechts. After that, the right resistance is presented in the frame of Fichte’s theory of the social contract. Finally I discuss the interpretations of Ingeborg Maus and Jean-Christophe Merle about these topics.

Performatividad, Poder y Parodia. El problema de la constitución y subversión de las identidades en la teoría de Judith Butler Suniga, Natalia Clelia El objetivo de este artículo consiste en reconstruir el espacio lógico y el contenido de la noción de identidad tal y como es expuesto en la teoría de Judith Butler. Y esto, teniendo en cuenta tanto los mecanismos que intervienen en el proceso de su constitución significante, como la posibilidad de parodiar e incluso de subvertir dichas construcciones. En este sentido, y siguiendo a Butler, retomaremos la noción de performatividad del discurso entendida como una práctica reiterativa y ritual de poder que produce aquello que nombra así como lo que queda fuera de la norma como su exterior, como base de su teoría. A partir de ello, la autora propone concebir a las identidades, que son siempre ya identidades de género, como construcciones performativas, un resultado de prácticas reiterativas cuyo efecto de naturalización esconde el proceso político e histórico que atraviesa su propia constitución. Aún más, Butler incluso destaca la posibilidad de que se produzca una reiteración tal que exponga paródicamente el carácter históricamente construido de las identidades, abriendo paso a la posibilidad de la subversión social y política.; This article is aimed at recreating the logical space and the content of the notion of identity as it is presented in the theory of Judith Butler. And this, considering the mechanisms that intervene at the process of its significant constitution, as well as the possibility to parody and even subvert those constructions. In this sense, and according to 2 Butler, we will understand the notion of performativity of discourse as a reiterative and ritual practice of power that produces not only what it names but also what remains outside the norm as its exterior, as a basis of her theory. With this in mind, the author proposes to conceive identities, understood as being always already gender identities, as performative constructions, a result of reiterative practices which effect of naturalization hides the historical and political process that goes through its own constitution. What is more, Butler even emphasizes the possibility of such a reiteration that exposes parodically the historically constructed nature of identities, opening the way to social and political subversion.

Analysis of four scales for global severity evaluation in Parkinson’s disease Martinez Martin, Pablo; Rojo Abuin, José Manuel; Rodríguez Violante, Mayela; Serrano Dueñas, Marcos; Garreto, Nélida Susana; Martínez Castrillo, Juan Carlos; Campos Arillo, Víctor; Fernández, William; Chaná Cuevas, Pedro; Arakaki, Tomoko; Alvarez, Mario Gustavo; Pedroso Ibañez, Ivonne; Rodríguez Blázquez , Carmen; Ray Chaudhuri , Kallol; Merello, Marcelo Jorge Global evaluations of Parkinson?s disease (PD) severity are available, but their concordance and accuracy have not been previously tested. The present international, cross-sectional study was aimed at determining the agreement level among four global scales for PD (Hoehn and Yahr, HY; Clinical Global Impression of Severity, CGIS; Clinical Impression of Severity Index, CISI-PD; and Patient Global Impression of Severity, PGIS) and identifying which of them better correlates with itemized PD assessments. Assessments included additional scales for evaluation of the movement impairment, disability, affective disorders, and quality of life. Spearman correlation coefficients, weighted and generalized kappa, and Kendall?s concordance coefficient were used. Four hundred thirty three PD patients, 66% in HY stages 2 or 3, mean disease duration 8.8 years, were analyzed. Correlation between the global scales ranged from 0.60 (HY with PGIS) to 0.91 (CGIS with CISI-PD). Kendall?s coefficient of concordance resulted 0.76 (P<0.0001). HY and CISI-PD showed the highest association with age, disease duration, and levodopa-equivalent daily dose, and CISI-PD with measures of PD manifestations, disability, and quality of life. PGIS and CISI-PD correlated similarly with anxiety and depression scores. The lowest agreement in classifying patients as mild, moderate, or severe was observed between PGIS and HY or CISI-PD (58%) and the highest between CGIS and CISI-PD (84.3%). The four PD global severity scales agree moderately to strongly among them; clinician-based ratings estimate PD severity, as established by other measures, better than PGIS; and the CISI-PD showed the highest association with measures of impairment, disability, and quality of life.

Los santos de la intemperie entran en la ciudad Lojo Calatrava, Maria Rosa Desde comienzos del siglo XXI las devociones populares no canónicas entran en las megalópolis argentinas (Buenos Aires, en especial). Resignifican culturas ancestrales, reactivan íconos y narrativas fundadores de la nacionalidad y la identidad, y se proyectan en nuevas formas artísticas sobre el espacio público. Un caso paradigmático es la devoción multitudinaria del Gauchito Antonio Gil.

Feminismo, cultura y política en Vanguardia, Caballo de Troya, América Gluzman, Georgina Gabriela Esta breve reseña se propone señalar ciertos aspectos vinculados a la interrogación del arte por el pensamiento feminista en la muestra Vanguardia, Caballo de Troya, América, integrada por las artistas argentinas Magdalena Jitrik y Leila Tschopp y curada por Florencia Qualina en el MACBA. Partiendo de una mirada interesada en la diferencia experiencial en el campo del arte, se analizan algunas relaciones entre mujeres artistas, historia del arte y abstracción. Este ejercicio de lectura considera al feminismo como fuerza política activa en el panorama cultural y no como una simple metodología de trabajo.

Youtubers. Nueva lógica comercial y narrativa en la producción de contenidos para la web; Youtubers. A new commercial and narrative logic in the production of content for the web López, Adrián Lucas En el presente estudio analizamos la lógica comercial de la distribución de contenidos a través de You Tube a partir de la observación de las diferentes estrategias y roles de los actores que participan, como los realizadores, los anunciantes y las empresas que se dedican a ofrecer asesoramiento, tanto en la producción de contenidos como en la realización de diferentes proyectos publicitarios en medios interactivos. En segundo lugar, desde un enfoque semiótico estudiamos la estructura del discurso y las principales modalidades de la enunciación de las producciones audiovisuales de You Tube en el caso de realizadores de habla hispana. Finalmente, ofrecemos una serie de proyecciones y tendencias generales para el futuro del sector, tanto a nivel comercial como narrativo.; In the present study we analyzed the business logic of the distribution of content via You Tube from the observation of the different strategies and roles of the actors involved, as the filmmakers, advertisers and companies that are dedicated to offering advice, both on content production and on advertising conducting different projects in interactive media. Secondly, from a semiotic approach we study the structure of the speech and the main modalities of enunciation of You Tube audiovisual productions in the case of Spanish-speaking filmmakers. Finally, we offer a series of projections and general trends for the future of the sector, both at commercial and narrative level.

High order eigenvalues for the Helmholtz equation in complicated non-tensor domains through Richardson extrapolation of second order finite differences Amore, Paolo; Fernández, Francisco Marcelo; Boyd, John. P.; Boris, Rösler We apply second order finite differences to calculate the lowest eigenvalues of the Helmholtz equation, for complicated non-tensor domains in the plane, using different grids which sample exactly the border of the domain. We show that the results obtained applying Richardson and Padé-Richardson extrapolations to a set of finite difference eigenvalues corresponding to different grids allow us to obtain extremely precise values. When possible we have assessed the precision of our extrapolations comparing them with the highly precise results obtained using the method of particular solutions. Our empirical findings suggest an asymptotic nature of the FD series. In all the cases studied, we are able to report numerical results which are more precise than those available in the literature.

En el Sur: ¿Conocimiento para qué? Preludio a un número sobre capitalismo, ideología y conflicto Seveso Zanin, Emilio José Señalar que la sensibilidad constituye un nodo analítico fundamental para el estudio de las sociedades, puede revestir cierta novedad. Afirmar que aquella está íntimamente relacionada con el estatus dependiente, periférico y neocolonial de los países latinoamericanos (y de sus formas de producción de saber) puede resultar más controvertido. Sin embargo, en un primer acercamiento, ésta relación no debería sorprendernos. Aquello que nos afecta, el cómo sentimos, pensamos y nos relacionamos con los otros; el modo en que valoramos, representamos y actuamos en el mundo; así como la manera en que apreciamos y establecemos vínculos y relaciones cotidianas, está configurado por la materia sensible que concreta nuestras prácticas. El modo en que nuestras sensibilidades son reguladas activamente determina no solo la constitución de nuestro presente, sino también la trama que conecta vida cotidiana y horizontes de transformación. El presente texto introductorio a la revista Fundamentos en Humanidades, número 29 (Año XV, número I), propone abordar nada menos que ese objeto esquivo y muchas veces relegado que es la sensibilidad. En términos analíticos, la propuesta se concreta como escenario productivo para (re)pensar los procesos de mediación cotidiana, especialmente como crítica a las matrices ideológicas corporizadas.

Electrochemical response of several cathode configurations prepared with Ba0.5Sr0.5Co0.8Fe0.2O3-δ and Ce0.9Gd0.1O1.95 for IT-SOFC Setevich, Cristian; Prado, Fernando Daniel; Caneiro, Alberto The electrochemical response of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) electrodes prepared by an acetic acid-based gel route has been investigated by impedance spectroscopy (IS) as a function of temperature (400 ≤ T ≤ 900 °C) and oxygen partial pressure (1 × 10−3 ≤ pO2 ≤ 1 atm). Several electrode configurations were studied using Ce0.9Gd0.1O1.95 (GDC) as the electrolyte. These consisted of one BSCF layer (cell A), a BSCF layer with an intermediate porous GDC layer (cell B), and graded electrodes using a composite BSCF+GDC, with variations in the surface area of GDC (cells C and D). The optimum heat treatment for the electrode assemblages was determined to be around 850–900 °C. Analysis of the impedance spectra shows that at T ≥ 600 °C a low frequency (LF) contribution, associated to the gas phase diffusion is systematically the rate-limiting step. All the electrodes show an intermediate frequency (IF) arc related to mixed processes. For cells A and B, the IF response is related to the oxide ion transfer at the electrode/electrolyte surface and the charge transfer at the electrode surface, while for cells C and D the mixed process involves the charge transfer and the molecular oxygen dissociation at the electrode surface.

The importance of biogeographical history and extant environmental conditions as drivers of freshwater decapod distribution in southern South America Tumini, Georgina; Giri, Federico; Williner, Verónica; Collins, Pablo Agustin A topical issue in macroecology is whether the distribution of organisms is related to biogeographical history or current environmental conditions. Distributions of freshwater decapods in southern South America have been mainly attributed to historical factors, such as geoclimatic events, marine ingressions, tectonic uplifts and glaciations. Here, we test the hypothesis that current distributions are strongly influenced by local environmental conditions. Generalised linear models were used to quantify the importance of altitude, stability of the waterbody, annual temperature range (ATR), pH and conductivity on the distribution of five freshwater decapod families in Argentina (Sergestidae, Palaemonidae, Parastacidae, Aeglidae and Trichodactylidae), while accounting for effects of latitude and longitude. Decapod occurrence was strongly associated with interacting spatial and environmental factors. Latitudinal and/or longitudinal gradients were important predictors for the occurrence of Acetes paraguayensis (Sergestidae), Palaemonidae, Aeglidae and Trichodactylidae. However, the longitudinal pattern for Palaemonidae was reversed, increasing from east to west, when environmental variables were included in the analyses, whereas for Trichodactylidae, the longitudinal pattern was sufficiently explained by inclusion of local environmental variables. Altitude, water stability and ATR were important predictors of all families, while Palaemonidae, Parastacidae and Trichodactylidae were significantly associated with pH and Palaemonidae and Aeglidae with conductivity. Interactions terms were often significant, especially with latitude. Our results show that the macrodistribution of freshwater decapods is not solely a result of historical processes, a finding that disagrees with current understandings. Significant relationships between decapod occurrence and environmental variables indicates limited plasticity and strong adaptation to local habitats, highlighting the importance of including environmental factors in studies of crustacean biogeography and macroecology.

FullSSR: Microsatellite Finder and Primer Designer Metz, Sebastián Darío; Cabrera, Juan Manuel; Rueda, Eva Carolina; Giri, Federico; Amavet, Patricia Susana Microsatellites are genomic sequences comprised of tandem repeats of short nucleotide motifs widely used as molecular markers in population genetics. FullSSR is a new bioinformatic tool for microsatellite (SSR) loci detection and primer design using genomic data from NGS assay. The software was tested with 2000 sequences of Oryza sativa shotgun sequencing project from the National Center of Biotechnology Information Trace Archive and with partial genome sequencing with ROCHE 454� from Caiman latirostris, Salvator merianae, Aegla platensis, and Zilchiopsis collastinensis. FullSSR performance was compared against other similar SSR search programs. The results of the use of this kind of approach depend on the parameters set by the user. In addition, results can be affected by the analyzed sequences because of differences among the genomes. FullSSR simplifies the detection of SSRs and primer design on a big data set. The command line interface of FullSSR was intended to be used as part of genomic analysis tools pipeline; however, it can be used as a stand-alone program because the results are easily interpreted for a nonexpert user.

Distributive Implications of Fertility Changes in Latin America Badaracco, Nicolás; Gasparini, Leonardo Carlos; Marchionni, Mariana Fertility rates significantly fell over the last decades in Latin America. In order to assess the extent to which these changes contributed to the observed reduction in income poverty and inequality we apply microeconometric decompositions to microdata from national household surveys from seven Latin American countries. We find that changes in fertility rates were associated to a non-negligible reduction in inequality and poverty in the region. The main channel was straightforward: lower fertility implied smaller families and hence larger per capita incomes. Lower fertility also fostered labor force participation, especially among women, which contributed to the reduction of poverty and inequality in most countries, although the size of this effect was smaller.

Transcranial electrical neuromodulation based on the reciprocity principle Fernandez Corazza, Mariano; Turovets, Sergei; Luu, Phan; Anderson, Erik; Tucker, Don A key challenge in multi-electrode transcranial electrical stimulation (TES) or transcranial direct current stimulation (tDCS) is to find a current injection pattern that delivers the necessary current density at a target and minimizes it in the rest of the head, which is mathematically modeled as an optimization problem. Such an optimization with the Least Squares (LS) or Linearly Constrained Minimum Variance (LCMV) algorithms is generally computationally expensive and requires multiple independent current sources. Based on the reciprocity principle in electroencephalography (EEG) and TES, it could be possible to find the optimal TES patterns quickly whenever the solution of the forward EEG problem is available for a brain region of interest. Here, we investigate the reciprocity principle as a guideline for finding optimal current injection patterns in TES that comply with safety constraints. We define four different trial cortical targets in a detailed seven-tissue finite element head model, and analyze the performance of the reciprocity family of TES methods in terms of electrode density, targeting error, focality, intensity, and directionality using the LS and LCMV solutions as the reference standards. It is found that the reciprocity algorithms show good performance comparable to the LCMV and LS solutions. Comparing the 128 and 256 electrode cases, we found that use of greater electrode density improves focality, directionality, and intensity parameters. The results show that reciprocity principle can be used to quickly determine optimal current injection patterns in TES and help to simplify TES protocols that are consistent with hardware and software availability and with safety constraints.

Misleading reporting and interpretation of results in major infertility journals Glujovsky, Demian; Sueldo, Carlos; Borghi, Carolina; Nicotra, Pamela; Andreucci, Sara; Ciapponi, Agustín Objective To evaluate the proportion of randomized controlled trials (RCTs) published in top infertility journals indexed on PubMed that reported their results with proper effect estimates and their precision estimation, while correctly interpreting both measures. Design Cross-sectional study evaluating all the RCTs published in top infertility journals during 2014. Setting Not applicable. Patient(s) Not applicable. Intervention(s) Not applicable. Main Outcome Measure(s) Proportion of RCTs that reported both relative and absolute effect size measures and its precision. Result(s) Among the 32 RCTs published in 2014 in the top infertility journals reviewed, 37.5% (95% confidence interval [CI], 21.1-56.3) did not mention in their abstracts whether the difference among the study arms was statistically or clinically significant, and only 6.3% (95% CI, 0.8-20.8) used a CI of the absolute difference. Similarly, in the results section, these elements were observed in 28.2% (95% CI, 13.7-46.7) and 15.6% (95% CI, 5.3-32.8), respectively. Only one study clearly expressed the minimal clinically important difference in their methods section, but we found related proxies in 53% (95% CI, 34.7-70.9). None of the studies used CIs to draw conclusions about the clinical or statistical significance. We found 13 studies where the interpretation of the findings could be misleading. Conclusion(s) Recommended reporting items are underused in top infertility journals, which could lead to misleading interpretations. Authors, reviewers, and editorial boards should emphasize their use to improve reporting quality.

Effect of different combinations of glycerol and/or trehalose on physical and structural properties of whey protein concentrate-based edible films Perez, Leonardo Martin; Piccirilli, Gisela Noemi; Delorenzi, Nestor Jorge; Verdini, Roxana Andrea The aim of the present study was to develop and characterize edible films produced from whey protein concentrate (WPC) and plasticized with different contents of glycerol (Gly) and/or trehalose (Tre) in order to evaluate new edible film formulations for their potential use in food packaging applications. Additionally, potential changes in the film mechanical properties during storage at ambient and freezing conditions were considered. Moisture content, solubility, thickness, transparency, microstructure, colour parameters, and mechanical properties were assessed. The films incorporated with Tre were more insoluble in water than WPC/Gly films, being more suitable for food applications. WPC/Gly and WPC/Tre films were clear enough to be used as see-through packaging. However, when Tre was included into WPC/Gly film formulations, film opacity increased. Scanning electron microscope (SEM) images suggested that this phenomenon may be related to the growth of Tre crystals in the film matrix. Moreover, when Tre concentration increased in the WPC/Gly matrix, film surface was more heterogeneous. Interestingly, the presence of Tre in WPC-based films was effective in preventing Maillard reaction after heating. WPC/Tre films were the most rigid but the least stable for storage, resulting more susceptible to rupture and cracking. Only WPC/Gly and WPC/Gly-Tre 8% films were rather flexible, manageable, and stable up to 90 days of storage under ambient and freezing conditions. These findings can be used to better design applications of edible films containing plasticizers that may crystallize over time in order to optimize film formulation in a rational manner towards their eventual application as food packaging.

Xylanase production by solid-state fermentation and study of separation with flexible polymers chains Gómez García, Ricardo; Medina, Miguel A.; Farruggia, Beatriz Monica; Picó, Guillermo Alfredo; Aguilar, Cristobal N. Xylanase is a key biocatalyst for several modern bioprocesses. It is required in large amounts and regularly it requires to be induced with xylan. Corn cob can be considered as an important source of xylan, for this reason the use of such agroindustrial residue can be an attractive alternative if it is used as support and nutrient source for fungal growth and xylanase production. One important aspect in the production of enzymes with industrial interest, refers to the process of recovery. Although the accumulation of extracellular enzymes during the solid-state fermentation facilitates their recovery, most of the methodologies used for time-consuming purification plus they are expensive and low yields. Aqueous two-phase systems (ATPS) are an attractive bioseparative technique for purification and ideal for the recovery of enzymes and other biomolecules due to the low interfacial tension and high water content, which provides a favorable environment for the preservation of the biological activity of labile molecules. In this study, it was possible to produce xylanase, allow us to obtain enzymatic activities at 2300 U L−1 and these results show us the ability of the microorganism to degrade and invade the substrate for growth. Enzyme was efficiently concentrated by ATPS