Peripheral neuroimmunoendocrine interactions: contribution of TNFRp55 to the circadian synchronization of progesterone and cytokine production in joints of mice in late pregnancy Arias, Jose Luis; Mayordomo, Andrea Constanza; Silva, Juan Eduardo; Ragusa, Juan Antonio Vicente; Rabinovich, Gabriel Adrián; Anzulovich Miranda, Ana Cecilia; Di Genaro, Maria Silvia Circadian rhythms are generated by the suprachiasmatic nucleus of the hypothalamus and involve rhythmic expression of clock genes and proteins. This rhythmicity is transferred to peripheral tissues by neural and hormonal signals. Late pregnancy is considered a state of inflammation which impacts on peripheral tissues such as joints. Tumor necrosis factor (TNF) mediates inflammatory and circadian responses through its p55 receptor (TNFRp55). Neuroimmunoendocrine interactions in joints have not been studied completely. The purpose of this study was to analyze these interactions, investigating the circadian rhythms of progesterone (Pg) and pro- and anti-inflammatory cytokines in the joints at the end of pregnancy (gestational day 18). Moreover, the impact of TNFRp55 deficiency on these temporal oscillations was explored.

Simultaneous co-immobilization of three enzymes onto a modified glassy carbon electrode to fabricate a high-performance amperometric biosensor for determination of total cholesterol Rashidi, Khodabakhsh; Mahmoudi, Majid; Mohammadi, Ghobad; Zangeneh, Mohammad Mahdi; Korani, Shahla; Goicoechea, Hector Casimiro; Gu, Hui-Wen; Jalalvand, Ali R. In this work, we have fabricated a novel amperometric cholesterol (CHO) biosensor because of the importance of determination of CHO levels in blood which is an important parameter for diagnosis and prevention of disease. To achieve this goal, cholesterol oxidase, cholesterol esterase and horseradish peroxidase were simultaneously co-immobilized onto a glassy carbon electrode (GCE) modified with gold nanoparticles/chitin-ionic liquid/poly(3,4-ethylenedioxypyrrole)/graphene-multiwalled carbon nanotubes-1,1′-ferrocenedicarboxylic acid-ionic liquid. Modifications applied to the bare GCE were characterized by cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. The biosensor detected CHO in linear ranges of 0.1–25 μM and 25–950 μM with a detection limit of 0.07 μM. The sensitivity of the biosensor was estimated to be 6.6 μA μM−1 cm−2, its response time was <5 s and Michaelis-Menten constant was calculated to be 0.12 μM. Results obtained in this study revealed that the biosensor was selective, sensitive, stable, repeatable and reproducible. Finally, the biosensor was successfully applied to the determination of CHO levels in rats plasma.

Do extrativismo neoliberal ao neoextrativismo progressivo? o caso da pesca marítima argentina (1989-2015); ¿Del extractivismo neoliberal al (neo)extractivismo progresista? El caso de la pesca marítima Argentina (1989-2015); From neoliberal extractivism toward progressive (neo)extractivism? The case of the Argentinean sea fishing (1989-2015) Gómez Lende, Sebastián Es un lugar común en la literatura académica especializada afirmar que, durante las últimas décadas, en América Latina se produjo una transición desde el paradigma extractivista ‘clásico’ neoliberal basado en el capital privado extranjero hacia un neo-extractivismo progresista donde el Estado impone controles más rigurosos, explota directamente la naturaleza, capta una porción sustancial de la renta y la redistribuye para legitimar socio-políticamente el modelo. Este artículo examina críticamente esa tesis y la contrasta empíricamente para la Argentina realizando un estudio comparativo de la pesca marítima durante el modelo neoliberal (1989-2001) y el régimen neo-desarrollista (2002-2015) a partir de cuatro dimensiones de análisis: desembarques, colapso del recurso y crisis pesquera; marco regulatorio, apertura al capital extranjero y estructura de la flota pesquera; boom exportador y apropiación estatal de la renta pesquera; y debilidad regulatoria, corrupción corporativo-institucional y depredación. Los resultados muestran que el Estado neo-desarrollista alentó la continuidad y maduración de la herencia neoliberal en el sector pesquero, consolidando la preexistente dinámica expoliadora, extranjerizante, privatista y extrovertida sin en contrapartida imponer controles públicos más estrictos, transparentes y eficaces, captar parte significativa de la renta ni implementar políticas que puedan ser juzgadas como ‘progresistas’; É um lugar comum na literatura acadêmica afirmar que, nas últimas décadas, na América Latina houve uma transição de paradigma neoliberal extrativo 'clássico' com base no capital privado estrangeiro para um neoextrativismo progressivo onde o Estado impõe controles mais rigorosos, explora diretamente a natureza, capta uma parte substancial da renda e a redistribui para legitimar politicamente o modelo. Este artigo examina criticamente esta tese e a contrasta empiricamente para Argentina através de um estudo comparativo da pesca marítima durante o modelo neoliberal (1989-2001) e o regime de neodesenvolvimentista (2002-2015) a partir de quatro dimensões de análise: desembarques de peixe, colapso do recurso e crisis do setor; enquadramento regulamentar, abertura ao capital estrangeiro e estrutura da frota pesqueira; boom de exportação e apropriação estadual da renta; e fraqueza regulatória, corrupção institucional-corporativa e depredação. Os resultados mostram que o Estado neo-desenvolvimentista incentivou a continuação e maturação de herança neoliberal no setor, reforçando a existente dinâmica de pilhagem, estrangeirização, privatização e extroversão sem, em contrapartida, impor controles públicos mais rigorosos, transparentes e eficazes, capturar parte significativa da renda ou implementar políticas “progressivas”.; During the last decades, the specialized academic literature has commonly stated that Latin America suffered a transition from the neoliberal classical extractive paradigm (i.e. based on foreign private capital) toward a progressive (neo)extractivism pattern where the State imposes more rigorous controls, directly exploits nature, captures a substantial portion of income, and redistribute it in order to politically legitimize such model. This article critically examines this thesis and empirically contrasts it for the Argentinean case by conducting a comparative study of sea fishing during the neoliberal model (1989-2001) and the neodevelopmentalist regime (2002-2015). Four dimensions of analysis were used: fish landings, the resource’s collapse, and the fishery crisis; regulatory framework, opening to foreign capital and the structure of the fishing fleet; exports boom and the state appropriation of fishing income; and regulatory weakness, corporate and institutional corruption and the resource’s depredation. The results show that the neodevelopmentalist State encouraged the continuity and maturation of the neoliberal heritage in the fishing sector by consolidating its preexisting dynamics (e.g. plundering, foreignization, privatization, extroversion, etc.) without, in return, imposing stricter, more transparent and effective controls, capturing a substantial piece of income or implementing any kind of ‘progressive’ policy

Determination of damage caused by different populations of Diloboderus abderus (Coleoptera: Scarabaeidae) larvae on wheat del Valle, Eleodoro Eduardo; Mayer, Gabriel F.; Mazuquín, Gabriel; Nari, Pablo; Toffoli Arnaudo, Guillermo Daniel; Imvinkelried, Horacio Omar Wheat (Triticum aestivum L.) is the most widely cultivated cereal crop worldwide because it is an important food source for humans. South America has long been associated with wheat production and export. Given the increased application of no till in the last decades, the scarabid Diloboderus abderus has become the main soil pest of this crop. The larvae of this insect (white grubs) feed on roots, causing plant weakening and death. The aim of this work was to determine the relationship between the soil population of D. abderus larvae and the number of established wheat plants. In a plot cultivated with the wheat cultivar Don Mario Algarrobo at a seeding rate of 130 kg ha-1 and with high population levels of this pest, 1-m2 sites with 20-39; 40-60; 80-100; 120-160 and or 200-240 plants were established. At the tillering phenological stage, the number of tillers per plant and of insect larvae in each subplot was counted. The results showed a significant reduction in plant density with increasing soil larval population. The crop counterbalanced the reduction in plant number by increasing the tiller number per unit area. The present work shows that population levels above 11 larvae m-2 generate a significant reduction in the number of wheat plants established in the crop.

Comments on "Dental homologies and evolutionary transformations in Caviomorpha (Hystricognathi, Rodentia): new data from the Paleogene of Peruvian Amazonia" Verzi, Diego Hector; Morgan, Cecilia Clara; Olivares, Adriana Itati We offer brief commentaries on Boivin and Marivaux's account of caviomorph molar morphology and evolution. In accordance with Van Valen’s statement ‘Homology is resemblance caused by a continuity of information’, we reaffirm that understanding the dental morphology of rodents should be focused on identifying, i.e. keeping in sight, a given structure undergoing multiple transformation processes in ontogeny and phylogeny. Many of these evolutionary pathways may be tracked with reasonable confidence and can provide keys to recognize widespread patterns.

A New Malachite Damselfly (Synlestidae: Odonata) from the Eocene of Patagonia, Argentina Petrulevicius, Julian Fernando A new synlestid zygopteran, Madres delpueblo n. gen. n. sp., is described from the middle Eocene of Río Pichileufú, Patagonia, Argentina. The new genus is characterised by wing characters such as the discoidal cell narrow and long; Ax2 aligned with the arculus; MP distinctly curved after its origin; CuP+AA fused to the hind margin half of the length of the discoidal cell; CuP closer to Ax2 than to Ax1. Needle damselflies or Malachites are represented in other two Patagonian Eocene localities, by nymphs and adults. The new genus enlarges the fossil record of Lestomorpha in Argentina to four extinct genera: Promegalestes, Austroperilestes, Inacayalestes and Madres n. gen. versus two Recent ones: Lestes and Archilestes.

Migración no autorizada y procesos de regularización en Argentina: el caso senegalés; Unauthorized migration and regularization processes in Argentina: the senegalese case Zubrzycki, Bernarda El objetivo de este trabajo es analizar el Régimen de Regularización Migratoria para ciudadanos senegaleses realizado en el año 2013 en el contexto de la nueva ley migratoria argentina, ley enmarcada en la perspectiva de la gobernabilidad migratoria. Las ideas que exponemos son resultados preliminares de una investigación en curso enfocada en analizar el impacto que tuvo el programa regulatorio en el colectivo de migrantes senegaleses. El caso senegalés vuelve a mostrar las limitaciones de la ley de migraciones, más allá de sus avances en materia de derechos para los migrantes. La inmigración persiste concebida como problema a partir de la irregularidad, donde los migrantes sólo pueden ser aceptados cuando su presencia lo amerita o cuando demuestran medios de vida “lícitos y útiles”. Y si bien para la ley la migración es un derecho, éste es ejercido de manera discrecional hacia ciertos grupos, por ejemplo, a través de la exigencia de visados.; The purpose of this study is to analyze the regime of migratory regularization for Senegalese citizens in the year 2013 in the context of the new Argentine immigration law.The ideas that we present are preliminary results of an ongoing study focused on analyzing the impact that the regulatory program had on the collective of Senegalese migrants.The Senegalese case shows the limitations of migration law, beyond advancement of rights for migrants. Immigration continues to be conceived as a problem of irregularity, migrants can only be accepted when something warrants their presence or when they show that their lives are "lawful and useful". And while migration is a right, it is exercised in a discretionary way towards certain groups, for example, through the requirement of visas.

Magnetic Remote Activation of Shape Recovery in Nanocomposites Based on Tung Oil and Styrene Meiorin, Cintia; Actis, Daniel Guillermo; Montoro, Fabiano E.; Moscoso Londoño, Oscar; Aranguren, Mirta Ines; Muraca, Diego; Mendoza Zélis, Pedro; Knobel, Marcelo; Mosiewicki, Mirna Alejandra The activation of unconstrained shape recovery in bio-based polymeric nanocomposites is successfully achieved using magnetic nanoparticle heating. The materials investigated in this work present several distinct physical and chemical characteristics worth pointing out: they can be deformed and the original shape can be recovered by remotely heating the samples above their switching temperature, which is determined by their glass transition temperatures. Also, their chemical composition is largely based on biomass (the polymeric matrix contains more than 50 wt.% of raw tung oil). Magnetic heating performance is strongly affected by both the physical properties and the concentration of the nanoparticles loaded into the matrix. The concentration of nanoparticles is associated with the formation of agglomerates or clusters, which determines the dipolar interactions among the nanoparticles. The particles used in this work are able to absorb enough energy from an alternating magnetic field to heat the matrix and initiate the shape recovery. Although the sample with the highest content of magnetic solute (10 wt.%) presents the highest degree of agglomeration, it is also the sample with the best remote activation of shape recovery, according to the temperature reached under magnetothermal measurements and the time of actuation.

Cross-Section Analysis of the Composition of Sprayed Cu 2 ZnSnS 4 Thin Films by XPS, EDS, and Multi-Wavelength Raman Spectroscopy Valdes, Matias Hernan; Pascual Winter, María Florencia; Bruchhausen, Axel Emerico; Schreiner, Wido H.; Vazquez, Marcela Vivian A detailed cross-section analysis of the chemical composition of sprayed Cu 2 ZnSnS 4 thin films is presented. X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy (with near-IR, visible, and UV-lasers) are used to demonstrate that while CZTS effectively forms within the bulk of the film, there is some degree of element segregation, formation of undesirable secondary phases, and the presence of a disordered kesterite structure across the film. Different penetration depths of the excitation signals correspond to the many different surface sensitive techniques employed in this work. XPS results reveal that the surface of Cu 4 ZnSnS 4 (CZTS) films presents a high concentration of tin and zinc and a low sulfur concentration, while being highly depleted in copper. EDS, XRD, and infrared Raman spectroscopy confirm that the composition of as-sprayed and sulfurized films is close to stoichiometric Cu 2 ZnSnS 4 . Resonant UV-Raman spectroscopy helps to identify secondary phases located at the external surface of sprayed and sulfurized CZTS films (mainly ZnS, ZnO), while VIS-Raman spectroscopy helps to identify a disordered kesterite structure close to the surface. Secondary phases need to be chemically etched when aiming at incorporating kesterite films obtained by spray pyrolysis into photovoltaic devices.

Optimal Multiproduct and Multiechelon Supply Chain Network Design Montagna, Agustín Francisco; Cafaro, Diego Carlos This work proposes a novel approach for the optimal design of multiproduct supply chain networks (SCN). Through a mixed integer linear programming (MILP) formulation the aim is to establish the structure of facilities that minimizes costs over the planning horizon, taking into account all the SCN's distinctive characteristics. We develop a generalized approach optimally determining the location of various types of facilities, multiproduct flows and demand fulfillment from any node in the network. This allows capturing the intertwined nature of decisions, leading to more efficient results. The proposed approach does not limit the number of echelons or layers. Instead, through a novel formulation, the optimal number of echelons is determined by the model, depending on the product to be supplied. To capture the economies of scale governing capital investments and operational costs, different types of facilities are proposed. Besides, the transportation expenses take different unitary costs according to the type of nodes being connected. Finally, the concept of waiting cost is introduced in order to capture the responsiveness of the SCN through the measurement of the time required to fulfill the clients? demands. A case study with different demand patterns and data structures is addressed to assess the potentials and efficiency of the SCN designs obtained with the proposed approach.

An effective continuous-time formulation for scheduling optimization in a shipbuilding assembly process Basán, Natalia Paola; Achkar, Victoria Gabriela; Garcia del Valle, A.; Mendez, Carlos Alberto This work aims at finding an optimal solution of assembly operations in a system of multi-stage production in a shipyard. Shipbuilding of large-size ships is a complex manufacturing process involving the production and assembly of a big quantity of blocks. These blocks are then assembled on the block erection final process, with a predefined order. To achieve competitiveness in this market, the development of efficient operation strategies is a potential alternative. To reach this objective, a mixed-integer linear mathematical model (MILP) is proposed. The model is based on the continuous time-slot time batches concept. This mathematical formulation allows obtaining efficient solutions to academic problems with reasonable computational effort. The MILP problem was tested and computational experiences were reported for industrial problems.

Testing modified gravity theory in the Milky Way Negrelli, Carolina Soledad; Benito, Maria; Landau, Susana Judith; Iocco, Fabio; Kraiselburd, Lucila We perform a test of John Moffat's modified gravity theory (MOG) within the Milky Way, adopting the well-known "rotation curve" method. We use the dynamics of observed tracers within the disk to determine the gravitational potential as a function of galactocentric distance and compare that with the potential that is expected to be generated by the visible component only (stars and gas) under different "flavors" of the MOG theory, making use of a state-of-the-art setup for both the observed tracers and baryonic morphology. Our analysis shows that in both the original and the modified version (considering a self-consistent evaluation of the Milky Way mass), the theory fails to reproduce the observed rotation curve. We conclude that in none of its present formulations is the MOG theory able to explain the observed rotation curve of the Milky Way.

Discapacidad: Tensiones entre la opresión y las prácticas liberadoras. Análisis desde el sur global; Disability: Tensions between oppression and liberating practices. Analysis from the global south Danel, Paula Mara El presente artículo recupera discusiones teórico-conceptuales que se originaron en la intersección de los aportes de la Diplomatura en Filosofía de la Liberación de la Universidad Nacional de Jujuy (UNJU) y los debates que venía sosteniendo en el campo de la discapacidad desde hace más de 18 años. Se toman las tensiones de la enunciación (las voces y los cuerpos) y la visualización como víctima de las personas en situación de discapacidad, desde las aperturas que propone Dussel para trabajar estos temas. En tal sentido, se recuperan análisis en torno a las discriminaciones que operan sobre aquellos que transitan su cotidianeidad en situación de discapacidad, y desde mi condición de trabajadora social en el campo doy cuenta de múltiples escenas interventivas en las que la discriminación, el deprecio por portar un cuerpo diferente y las sospechas sobre la condición ciudadana se hacen palabras, miradas e intervenciones. El presente trabajo retoma una experiencia formativa en Filosofía de la Liberación, en diálogo profundo con los debates del Trabajo Social. Mi lugar de enunciación es Argentina, país situado “nuestra América”. Desde este locus de enunciación me interrogo en torno a los desafíos contemporáneos para que las distintas formaciones sociales produzcan relaciones libres de opresiones.; The present scientific article recovers theoretical-conceptual discussions that originated in the intersection of the contributions of the Philosophy of Liberation of the National University of Jujuy (UNJU) and the debates that it had been holding in the field of disability for more than 18 years. We take the tensions of enunciation (voices and bodies), visualization as a victim of people with disabilities and from the openings that Dussel proposes to work on these issues. In this sense, analysis is retaken around the discriminations that operate on those who travel their daily life in a situation of disability, and from my condition of social worker in the field I realize multiple intervention scenes in which the discrimination, the depreciation by Carry a different body and suspicions about the condition of citizens become words, looks and interventions. The present work takes up a formative experience in Philosophy of Liberation, in deep dialogue with Social Work debates. My place of enunciation is Argentina, a country located "our America". From this locus of enunciation I question myself about the contemporary challenges so that the different social formations produce relations free from oppression.

From morphology to molecules: A combined source approach to untangle the taxonomy of Clessinia (Gastropoda, Odontostomidae), endemic land snails from the Dry Chaco ecoregion Cuezzo, Maria Gabriela; Miranda, Maria Jose; Vogler, Roberto Eugenio; Beltramino, Ariel Anibal Background: Land gastropods of the Dry Chaco merit special attention because they comprise a highly diverse but barely studied group. Clessinia Doering, 1875 are typical inhabitants of this ecoregion. The inclusion of their distribution areas into Spixia range, their shell shape similarities, and a former molecular study raised doubts on the monophyly of this genus. The present study review the species of Clessinia, under a morphological, geometric morphometrics, and molecular combined approach. Methods: Adults were collected, photographed, measured, and dissected for anatomical studies. Shell ultrastructure was studied with scanning electron microscope. Geometric morphometric analyses on shells were performed testing if they gave complementary information to anatomy. Two mitochondrial genes, and a nuclear region were studied. Phylogenetic reconstructions to explore the relationships of DNA sequences here obtained to those of Clessinia and Spixia species from GenBank were performed. Results: Species description on shell, periostracal ornamentation and anatomy is provided. We raised former Clessinia cordovana striata to species rank, naming it as Clessinia tulumbensis sp. nov. The periostracum, consisting of hairs and lamellae, has taxonomic importance for species identification. Shell morphometric analyses, inner sculpture of penis and proportion of the epiphallus and penis, were useful tools to species identification. Nuclear markers do not exhibit enough genetic variation to determine species relationships. Based on the mitochondrial markers, genetic distances among Clessinia species were greater than 10%, and while C. cordovana, C. nattkemperi, and C. pagoda were recognized as distinct evolutionary genetic species, the distinction between C. stelzneri and C. tulumbensis sp. nov. was not evident. Clessinia and Spixia were paraphyletic in the molecular phylogenetic analyses. Species of Clessinia here treated have narrow distributional areas and are endemic to the Chaco Serrano subecoregion, restricted to small patches within the Dry Chaco. Clessinia and Spixia are synonymous, and the valid name of the taxon should be Clessinia Doering, 1875 which has priority over Spixia Pilsbry & Vanatta, 1894. Discussion: Our results support the composition of C. cordovana complex by three species, C. cordovana, C. stelzneri, and C. tulumbensis sp. nov. The low genetic divergence between C. stelzneri and C. tulumbensis sp. nov. suggests that they have evolved relatively recently. The former Spixia and Clessinia are externally distinguished because Clessinia has a detached aperture from the body whorl forming a cornet, periostracal microsculpture extended over dorsal portion of the peristome, five inner teeth on the shell aperture instead of three–four found in Spixia. Morphological similarities exists between both genera in shell shape, type of periostracum microsculpture, reproductive anatomy, besides the overlap in geographic ranges.

RPA(D) and HRPA(D): Two new models for calculations of NMR indirect nuclear spin–spin coupling constants Schnack Petersen, Anna Kristina; Haase, Pi A. B.; Faber, Rasmus; Provasi, Patricio Federico; Sauer, Stephan P. A. In this article, the RPA(D) and HRPA(D) models for the calculation of linear response functions are presented. The performance of the new RPA(D) and HRPA(D) models is compared to the performance of the established RPA, HRPA, and SOPPA models in calculations of indirect nuclear spin–spin coupling constants using the CCSD model as a reference. The doubles correction offers a significant improvement on both the RPA and HRPA models; however, the improvement is more dramatic in the case of the RPA model. For all coupling types investigated in this study, the results obtained using the HRPA(D) model are comparable in accuracy to those given by the SOPPA model, while requiring between 30% and 90% of the calculation time needed for SOPPA. The RPA(D) model, while of slightly lower accuracy compared to the CCSD model than HRPA(D), offered calculation times of only approximately 25% of those required for SOPPA for all the investigated molecules.

El desarrollo económico de la provincia de Santa Fe: datos y representaciones en los discursos oficiales. Ríspolo, Florencia Daniela; Zanardi, Julieta Rocio El presente trabajo parte de la premisa de que los discursos nos permiten conocer las representaciones que cada hablante posee sobre la realidad; por lo tanto, los discursos emitidos por los dirigentes políticos, nos permitirían conocer la mirada que cada gobierno posee entorno a la sociedad sobre la que detenta su poder. En este sentido, el artículo pretende corroborar si la perspectiva sobre el desarrollo económico que se plantea en los discursos de los gobernadores santafesinos, se corresponde con los datos que relevan de las fuentes estadísticas de la misma provincia.Con este objetivo, se buscará poner en discusión las estadísticas oficiales relativas a las principales áreas de desarrollo económico y el discurso político elaborado por los dos últimos gobernadores de la provincia. Para ello fueron considerados los discursos políticos emitidos entre los años 2014-2017 en la apertura de sesiones legislativas provinciales y los datos estadísticos provenientes de distintas fuentes oficiales.

Optimización multidimensional del sistema previsional argentino Geri, Milva Con el propósito de optimizar el desempeño multidimensional del sistema previsional argentino se propone un modelo de optimización sujeto a restricciones que tiene por función objetivo la minimización de la inequidad que resulta de la interacción entre las tres grandes dimensiones del desempeño previsional, a saber: i) la cobertura, ii) la adecuación de las prestaciones y iii) la sostenibilidad. Para el logro de esa meta fue necesario introducir al sistema previsional como objeto de estudio de la teoría económica y de dos importantes organismos internacionales, quienes protagonizaron un extenso debate acerca del diseño óptimo de estos subsistemas de la seguridad social en la década del „90. Al mismo tiempo, se consideró el impacto de fenómenos demográficos sobre la sostenibilidad de los sistemas previsionales de acuerdo a la teoría de los bonos demográficos. Una vez introducido el problema, se procedió a compilar la información contenida en más de dos mil normativas vigentes o derogadas que crearon, regularon o modificaron regímenes previsionales argentinos desde principios del siglo XX, así como sus parámetros más relevantes. Se construyó así la evolución histórica de nuestro sistema previsional, sistematizando el valor de los principales parámetros y variables involucrados en su funcionamiento. Dicho esfuerzo permite contemplar las experiencias pasadas al momento de comprender la situación actual y pensar posibles alternativas de reforma de cara al futuro. El siguiente paso consistió en la evaluación del desempeño multidimensional del sistema previsional durante los últimos veintitrés años, comprendiendo el período que se inicia con la reforma previsional que entró en vigencia en julio de 1994 y termina en el cuarto trimestre de 2017. Las tres dimensiones del desempeño se evaluaron en términos generales promedio, según género y nivel de ingreso, poniendo en evidencia las distintas equidades o inequidades que genera el funcionamiento del sistema previsional. El último paso consistió en el planteo del modelo de optimización, para lo cual fue necesario ejemplificar el uso de herramientas de modelado, simulación y optimización en materia previsional a partir de la revisión de la literatura pertinente. Asimismo, se justificó la definición de la función objetivo en aspectos relacionados a una hipotética función de bienestar social de la cual podría derivarse. Posteriormente se planteó el modelo, se lo calibró a partir de información poblacional y muestral y se obtuvieron los resultados. Finalmente se efectuaron análisis de sensibilidad para evaluar la robustez de los resultados y se presentaron las reflexiones y consideraciones que surgen de ellos. Se concluye que la complejidad de los problemas reales constituye un desafío para la teoría económica, la cual debiera esforzarse en emplear todas las herramientas que tiene a su disposición para incorporar el mayor nivel de realismo posible a los supuestos de los cuales parte, en detrimento de la parsimonia pero a favor del ofrecimiento de soluciones adecuadas que puedan ser consideradas útiles por un tomador de decisión en el ámbito previsional.; In order to optimize the multidimensional performance of the Argentine pension system, the thesis proposes an optimization model subject to restrictions whose objective function is to minimize the inequity that results from the interaction between the three large dimensions of pension performance, namely: i) coverage, ii) adequacy of benefits and iii) sustainability. To achieve this goal, it was necessary to introduce the pension system as a subject of study of economic theory and of two important international organizations, who carried out an extensive debate about the optimal design of these social security subsystems in the 1990s. At the same time, the impact of demographic phenomena on the sustainability of pension systems was considered according to the theory of demographic dividends. Once the problem was set, the information contained in more than two thousands current or repealed norms that created, regulated or modified Argentine pension systems throughout its history since the beginning of the 20th century was compiled. The historical evolution of our pension system was thus constructed, systematizing the value of the main parameters and variables involved in its functioning. This effort allows contemplating past experiences to increase our understanding of the current situation and thinking about possible alternatives for the future. The next step consisted in the evaluation of the multidimensional performance of the pension system during the last twenty-three years, including the period that begins with the pension reform in July 1994 and ended in the fourth quarter of 2017. The three performance dimensions were assessed in general average terms, according to gender and income level, highlighting how the pension system performs in terms of equity. In the last step the optimization model is presented. To arrive at this model it was necessary to review the literature on pensions systems to assess how modeling, simulation and optimization tools are used. Likewise, the definition of the objective function was justified in aspects related to an hypothetical social welfare function from which it could be derived. To run the model, it was first calibrated based on population and sample information. Finally, in order to analyze the results, sensitivity analyses were carried out to evaluate the robustness of the results and the reflections and considerations that arise from them were presented. To conclude, we interpret and discuss the results. It is concluded that the complexity of real problems poses a challenge, and that economic theory should strive to use all the tools at its disposal to incorporate an adequate level of realism to the assumptions from which it departs. This may be to the detriment of parsimony but in favor of offering viable solutions that can be considered useful by decision makers in the social security field.

Feasibility of dose enhancement assessment: Preliminary results by means of Gd-infused polymer gel dosimeter and Monte Carlo study Santibáñez, M.; Guillen, Y.; Chacón Obando, David; Figueroa, R.G.; Valente, Mauro Andres This work reports the experimental development of an integral Gd-infused dosimeter suitable for Gd dose enhancement assessment along with Monte Carlo simulations applied to determine the dose enhancement by radioactive and X-ray sources of interest in conventional and electronic brachytherapy. In this context, capability to elaborate a stable and reliable Gd-infused dosimeter was the first goal aimed at direct and accurate measurements of dose enhancement due to Gd presence. Dose-response was characterized for standard and Gd-infused PAGAT polymer gel dosimeters by means of optical transmission/absorbance. The developed Gd-infused PAGAT dosimeters demonstrated to be stable presenting similar dose-response as standard PAGAT within a linear trend up to 13 Gy along with good post-irradiation readout stability verified at 24 and 48 h. Additionally, dose enhancement was evaluated for Gd-infused PAGAT dosimeters by means of Monte Carlo (PENELOPE) simulations considering scenarios for isotopic and X-ray generator sources. The obtained results demonstrated the feasibility of obtaining a maximum enhancement around of (14 ± 1)% for 192 Ir source and an average enhancement of (70 ± 13)% for 241 Am. However, dose enhancement up to (267 ± 18)% may be achieved if suitable filtering is added to the 241 Am source. On the other hand, optimized X-ray spectra may attain dose enhancements up to (253 ± 22) %, which constitutes a promising future alternative for replacing radioactive sources by implementing electronic brachytherapy achieving high dose levels.

Desigualdad espacial, género y acceso a la vivienda: un estudio sobre trayectorias juveniles en el AMBA, 1999-2017 Arancibia, Milena Maia Durante las últimas décadas, la globalización, los procesos de fragmentación territorial y su impacto en la segmentación social han generado una gran heterogeneidad en las transiciones juveniles. Particularmente, en los países de América Latina en los que preocupa la persistencia de la desigualdad, el interés por las trayectorias juveniles que no se dan dentro de los parámetros normativos ha ido creciendo. Este es el caso de los que quedan al margen de la integración en el mercado de trabajo, como los jóvenes con inserciones laborales extremadamente irregulares o las mujeres que asumen tareas de cuidado en sus hogares desde edades tempranas y que signan trayectorias de escasa relación con el empleo. Mientras que la tradición de los estudios sobre juventud estuvo centrada en la transición educativo-laboral que lleva a la independencia del individuo adulto, en años recientes, en diversos países los sociólogos de la juventud han incorporado a sus desarrollos teóricos las dimensiones de tiempo, espacio y arraigo, como otros factores intervinientes en los procesos de transición. Un concepto recientemente desarrollado que intenta resumir la variedad, interrelación y complejidad de estas dimensiones para analizar las trayectorias juveniles es el concepto de gramáticas de la juventud. El mismo aborda la relación entre las estructuras de actividades ofrecidas y las expectativas que las sociedades contemporáneas establecen para los distintos grupos de jóvenes. La tesis se inspira en estas perspectivas y toma en cuenta algunas de las nuevas dimensiones de análisis. Por otro lado, se basa en la noción de reproducción social ampliada que pone en cuestión la concepción tradicional de trabajo. Desde dicha perspectiva, se incorporan formas invisibilizadas de trabajo (tareas domésticas y trabajos de cuidado) en el análisis del proceso hacia la autonomía de las jóvenes mujeres. En síntesis, esta investigación analiza diversas trayectorias juveniles de mujeres y varones, de diferentes sectores sociales, que habitan diferentes espacios, en un mismo contexto sociohistórico (el Área Metropolitana de Buenos Aires, entre 1999 y 2017). Mediante el trabajo analítico realizado se indagan las transiciones educativo-laborales, familiares y residenciales y su intersección con los modelos normativos de transición a la vida adulta. Se pone el foco tanto en las decisiones de los jóvenes en el proceso de construcción de sus proyectos de vida como en las posibilidades con las que se encuentran en los distintos espacios donde habitan en el período sociohistórico en el que transcurren su juventud.El análisis de las trayectorias juveniles en el AMBA se inscribe en una estrategia cualitativa, en base al método biográfico. Se aborda el análisis de un conjunto de entrevistas retrospectivas realizadas con mujeres y varones que nacieron sobre principios de los años 80, y que alcanzaron la mayoría de edad sobre finales de siglo veinte. Los relatos se corresponden con un trabajo de campo realizado entre 2013 y 2017, cuando los jóvenes tenían entre 32 y 34 años. La selección de los 52 entrevistados se basó en una muestra segmentada según el nivel educativo alcanzado, el género y las características del hábitat, que incluyó barrios relegados (tanto modalidades informales como barrios de interés social) y barrios predominantemente de clase media. Los barrios estuvieron localizados en los municipios Avellaneda, Lanús, Moreno, Morón, San Fernando, San Martín, San Miguel, La Plata, Tigre, Vicente López, Berazategui, La Matanza, Tres de Febrero y CABA.A partir del análisis comparativo realizado y en base al concepto de gramáticas de la juventud, esta tesis identificó las especificidades de las trayectorias de jóvenes de distintos sectores sociales, tipos de barrios y géneros. Por este motivo, la presente investigación contribuyó a profundizar en el estudio de las gramáticas de la juventud en Argentina a través de la incorporación del análisis del espacio, el arraigo y el género, dimensiones que no habían sido analizadas en forma conjunta por otros estudios. Uno de los principales hallazgos de la investigación puso en evidencia cómo la dimensión espacial de la vida social configura el acceso diferenciado a redes y recursos entre mujeres y varones jóvenes, lo cual habilita la construcción de proyectos de vida fuertemente diferenciados y con diferentes escalas de arraigo. Se concluyó que en ciudades fragmentadas y donde persiste una fuerte división sexual del trabajo existe una gramática en la que se desarrolla un arraigo al lugar fuertemente ligado al espacio barrial y, en oposición, otra caracterizada por un arraigo flexible ligado a la escala global. Las trayectorias de las y los jóvenes que se desarrollan en distintos tipos de barrio y con gramáticas juveniles segmentadas refuerzan la desigualdad, y ésta afecta en mayor medida a las mujeres.La evidencia presentada contribuye a la acumulación de conocimiento acerca de cómo las y los jóvenes transitan el proceso de transición a la vida adulta, para la formulación de políticas públicas tendientes a igualar sus derechos y oportunidades. Por último, con los resultados del estudio se aporta al debate teórico sobre la desigualdad en la región y la relación entre espacio social y acción.; During the last decades, globalization, territorial fragmentation and their impact on social segmentation determined great heterogeneity in youth transitions. Especially in Latin American countries with high levels of inequality there is a growing interest in youth trajectories that do not develop within the normative parameters. This is the case of those who are excluded from the labor market, such as young people with extremely irregular jobs or women who do house-hold tasks from early ages. While traditional youth studies have focused exclusively on the educational-labor transition leading to independence in adults, current youth studies in several countries have incorporated into their theoretical framework new dimensions, like time, space and belonging. The concept of grammars of youth is a recently developed concept that attempts to summarize the variety, interrelation and complexity of these dimensions to analyze youth trajectories. It addresses the relationship between the structures of activities offered and the expectations that contemporary societies establish for different groups of young people. The thesis is inspired by these perspectives and considers some of the new dimensions of analysis. On the other hand, it is based on the notion of extended social reproduction that calls into question the traditional conception of work which appear ineffective for the analysis of female transition as caregiving work and extended social reproduction are not considered. My overarching goal is to analyze differences in youth trajectories of women and men from different social backgrounds, who lived in different types of neighborhoods of the Metropolitan Area of Buenos Aires (AMBA), between 1999 and 2017. I analyze the educational-labor, family and residential transitions, as well as their intersection with normative models of transition from young to adult life available in the current Argentine context. These dimensions are critical to analyze both young people’s decisions in the process of building their life projects and the possibilities they face in the varying socio-historical contexts and spaces. From a qualitative methodology, I adopted a biographic approach to interview 52 women and men that were born in the early 80s and reached the age of majority at the end of the twentieth century. I conducted fieldwork between 2013 and 2017, when young people were between 32 and 34 years old. The subject selection was based on a segmented sample, defined according to educational level, gender and habitat characteristics, which included relegated neighborhoods (both shantytowns and housing projects) and middle-class neighborhoods. The neighborhoods are located in the municipalities of Avellaneda, Lanús, Moreno, Morón, San Fernando, San Martín, San Miguel, La Plata, Tigre, Vicente López, Berazategui, La Matanza, Tres de Febrero and CABA. Through a comparative analysis and based on the concept of grammars of youth, I identified differences in the trajectories of young people from different social sectors and genders. For this reason, this research contributed to deepen the study of grammars of youth in Argentina through the incorporation of space analysis, belonging and gender, which had not been analyzed jointly by other studies. My fieldwork findings have shown strongly differentiated life projects built on different spatial scales. The spatial dimension of social life configures access to networks and resources between women and young men, enabling the construction of strongly differentiated scales of belonging. The process of territorial fragmentation and the persistence of sexual division of labor shape widely diverse experiences of transition and configures different grammars of youth. The first form related to a belonging that is sustained in global flows, in highly connected cities. On the other, the strong bond of belonging to the neighborhood signaled locally situated trajectories, constituting an alternative to the hegemonic grammar of youth. The trajectories of young people developed in different types of neighborhoods and with segmented youth scales of belonging reinforce inequality, affecting particularly young women. The analysis of the different sense of belonging has allowed me to understand the vital decisions made, contributing to the knowledge of youth trajectories in Argentina. Faced with the differences pointed out, I hold that the development of policies aimed at young people rights (considering access to education, employment but also support caring tasks) are key element in achieving social justice. Finally, the results of the study contribute to the theoretical debate on Latin American inequality and the relationship between action and social space.

Fungal quality and molecular characterization of aflatoxin-producing Aspergillus species in irrigation water and fresh vegetables in Southwest Nigeria Akinde, Sunday Babatunde; Olaitan, Janet Olubukola; Ajayi, Ebenezer Idowu O; Adeniyi, Mobolaji Adenike; Ige, Oluwatobi Oluwasegun; Adebooye, Odunayo Clement Fungal species were isolated from irrigation water, cultivation soil, and fresh vegetables samples were obtained from a vegetable field in Southwest Nigeria. Aspergillus group, identified by amplification and sequencing of their internal transcribed spacer (ITS) region, were further characterized for aflatoxin production using standard spectrophotometry (365 nm). The highest mean ± SD fungal counts were 3.23 x 103 ± 0.03 CFU/g, 3.07 x 104 ± 0.01 CFU/g and 8.67 x 102 ± 0.13 CFU/ml for vegetable, soil, and water samples, respectively. A total of 32 fungal strains isolated were presumptively identified as Aspergillus sp. (50%), Fusarium sp. (6.25%), Chrysonilia sitophila (3.13%), Acremonium sp. (6.25%), Mucor sp. (12.5%), and Rhizopus sp. (21.87%). The molecular characterization of Aspergillus strains revealed Aspergillus aculeatus, Aspergillus fijiensis, Aspergillus flavus, Aspergillus japonicas, and Aspergillus niger. All the 16 Aspergillus species showed aflatoxin B1 production with Aspergillus japonicus (AWF27) isolated from the irrigation water having the highest concentration (106 µg/kg) and Aspergillus fijiensis (ASF6) isolated from soil having the lowest concentration (93 µg/kg). The work revealed the potential for human exposure to mycotoxin through contaminated fresh vegetables. Concerted effort is required, especially in developing countries for cultivation of fresh vegetables in hygienic environment with clean irrigation water.