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Los límites de las perspectivas teóricas liberales para estudiar las democracias en las provincias argentinas

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Los límites de las perspectivas teóricas liberales para estudiar las democracias en las provincias argentinas; The limits of liberal theoretical perspectives to study democracies in Argentine states Campos, Hernán El artículo propuso identificar algunos elementos teóricos epistémicos para repensar las democracias en las provincias de Argentina, en especial la de Santiago del Estero. El interés surge de un proceso de investigación sobre las redes partidarias, en donde se indaga sobre las formas de construir representación política y democracia. Se exploraron los artículos de Gibson: “Autoritarismo subnacional: estrategias territoriales de control político en regímenes democráticos”, y de Gervasoni: “Democracia, autoritarismo e hibridez en las provincias argentinas: la medición y las causas de los regímenes subnacionales”, para tensionar las bases liberales del pensamiento de estos autores. La posibilidad de pensar los aspectos epistemológicos, no es a los fines de descalificar o de señalar la inviabilidad de sus argumentos, sino de ir más allá. Advirtiendo la necesidad de la reflexividad del sujeto investigador. Es decir, objetivar la situacionalidad desde donde se piensa, de lo que se dice y de los efectos políticos del saber académico.; The article set out to identify some epistemic theoretical elements to rethink democracies in the provinces of Argentina, especially Santiago del Estero. The interest arises from a process of research on party networks, in which the forms of constructing political representation and democracy are investigated. The articles by Gibson: “Subnational authoritarianism: territorial strategies of political control in democratic regimes”, and Gervasoni: “Democracy, authoritarianism and hybridity in the Argentine provinces: the measurement and causes of subnational regimes”, were explored in order to test the liberal bases of these authors’ thinking. The possibility of thinking about epistemological aspects is not for the purpose of disqualifying or pointing out the unfeasibility of their arguments, but to go beyond them. It is to note the need for reflexivity on the part of the research subject. That is to say, to objectify the situationality of where one thinks, of what is said and of the political effects of academic knowledge.

Solar Energy in Argentina

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Solar Energy in Argentina Bragagnolo, Julio A.; Taretto, Kurt Rodolfo; Navntoft, Christian There is a large gap between the vast solar resources and the magnitude of solar energy deployment in Argentina. In the case of photovoltaics, the country only reached the 1000 GWh electricity generated yearly landmark in 2020. Solar thermal technology is even less developed, in part due to the low natural gas prices resulting from political strategies that aim to soften the impact of an unstable economy on family budgets. This review describes this gap by summarizing the current state of Argentine solar energy. We summarize the fundamental legal and strategic tools which are available for solar energy deployment, survey the penetration of solar energy into the country?s energy landscape, identify national contributions to the local value chain, and review past and present research and development achievements. Both photovoltaic and solar thermal technologies show a historical fluctuation between local technology development and imported technology and know-how. Finally, a discussion on the main ingredients required to abridge Argentina?s solar gap indicates that stronger, consistent long-term strategies are required in Argentina in order to take advantage of the present window of opportunity, and to play a considerable role in the global energy transition.

Hacia la evaluación perceptual forense: Transformación de puntajes de similitud a relaciones de verosimilitud. Parte 2: hablantes femeninos

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Hacia la evaluación perceptual forense: Transformación de puntajes de similitud a relaciones de verosimilitud. Parte 2: hablantes femeninos Masessa, Evangelina; Suligoy, Stefanía; Molina, N.; Torres, Humberto Maximiliano; Univaso, Pedro; Gurlekian, Jorge Alberto Objetivo: obtener las distribuciones probabilísticas de las respuestas a la evaluación de pares de voces femeninas provenientes de la misma y diferentes hablantes que permiten desarrollar el método indirecto para el cálculo del cociente de verosimilitudes (LR). Desarrollo experimental: se inicia con la creación de una base de datos que considera el diseño de 2520 frases, las cuales serán emitidas por 40 hablantes femeninos nativos de Argentina, en distintas sesiones. Se crearon estímulos con pares de frases provenientes de la misma y de distintas hablantes combinando frases diferentes grabadas en distintas sesiones. Se realizó la evaluación auditiva de los pares donde los oyentes debían indicar si las dos frases habían sido generadas por un mismo hablante o por distintas hablantes, indicando el grado de confianza en la respuesta. Resultados: a partir de las respuestas de los evaluadores, se estimaron las funciones de densidad de probabilidad para pares provenientes del mismo hablante y de diferentes hablantes. Al comparar las respuestas acumulativas de 1 a 5 oyentes para comprobar el efecto del número de evaluadores en las distribuciones obtenidas, se verifica una disminución en las mediciones de error efectuadas.Conclusiones: La evaluación perceptual de voces permite representar las funciones distribución de probabilidad de las respuestas a pares de voces de un mismo y diferentes hablantes provenientes de una población de hablantes nativos femeninos. Con las distribuciones estimadas será posible realizar la conversión del puntaje resultante de las comparaciones de la evidencia a los cocientes de verosimilitudes, denominado en el ámbito forense como la fuerza de la evidencia.; : Objective: to obtain the probabilistic distributions of the responses to the evaluation of pairs of female voices coming from the same and different speakers that allow the development of the indirect method for the calculation of the likelihood ratio (LR). Experimental development: it starts with the development of a database that considers the design of 2520 sentences, which will be emitted by 40 female native speakers from Argentina, in different sessions. Pairs of sentences from the same and different speakers were created by combining different sentences recorded in different sessions. The auditory evaluation of the pairs was carried out where the listeners had to indicate whether the two sentences had been generated by the same speaker or by different speakers, indicating the degree of confidence in the response. Results: from the evaluators' responses, probability density functions were obtained for pairs coming from the same speaker and from different speakers. When comparing the cumulative responses from 1 to 5 listeners to check the effect of the number of evaluators on the distributions obtained, a decrease in the error measurements was verified. Conclusions: The perceptual evaluation of voices makes it possible to represent the probability distribution functions of the responses to pairs of voices from the same and different speakers from a population of female native speakers. With the distributions obtained it will be possible to convert the score resulting from the evidence comparisons into likelihood ratios, known in the forensic field as "the strength of the evidence".

Tolerancia al estrés por sal y cadmio en cuatro genotipos de Medicago sativa L

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Tolerancia al estrés por sal y cadmio en cuatro genotipos de Medicago sativa L; Salt and Cadmium Stress Tolerance in Four Genotypes of Medicago sativa L Pacheco Insausti, María Cecilia; Zapico, Martín Gonzalo; González, Evelyn A.; Fernández, Eliana; Gutiérrez, Mariano H.; Stege, Patricia Wanda; Pedranzani, Hilda Elizabeth Objetivo: Evaluar la tolerancia de cuatro genotipos de Medicago sativa L. a la salinidad y cadmio, mediante el estudio de la geminación, parámetros de crecimiento, pigmentos fotosintéticos y respuesta osmocompatible. Materiales y métodos: El diseño experimental fue completamente al azar con arreglo factorial: tipo de genotipo: CW 197, Trinidad 87, CW 660 y Salina PV y niveles de estrés salino (NaCl) y cadmio (Cl2Cd) estrés. Se realizó ANOVA factorial para identificar la influencia de las condiciones de estrés en las variables medidas, se realizaron análisis de comparaciones múltiples de medias cuando se encontró un efecto significativo. Se sembraron 20 semillas por triplicado regadas con agua (control) y soluciones entre 10 a 200 mM de NaCl y 100 a 500 µM de Cl2Cd para el estudio de germinación. En plántulas de cuatro semanas crecidas en terrinas regadas con solución nutritiva (control) y concentraciones crecientes de NaCl (50-200 mM) y Cl2Cd (25µM-100 µM) se midieron crecimiento, prolina y pigmentos fotosintéticos. Resultados: Bajo salinidad, los genotipos CW179 y CW660 fueron tolerantes a la salinidad en la germinación, y los genotipos Salina PV y Trinidad 87 fueron más tolerantes durante el crecimiento. En respuesta a Cd, los genotipos mostraron tolerancia durante el crecimiento. La prolina fue osmoprotectora frente a la salinidad, pero no contra el estrés por Cd. Los pigmentos fotosintéticos disminuyeron con el estrés salino; sin embargo, Cd no los afectó. Conclusión: El genotipo CW 660 fue el más tolerante a la salinidad y al Cd durante la germinación. Se concluye que los genotipos Trinidad 87 y Salina PV son tolerantes a la sal y los genotipos CW 197 y CW 660 son sensibles, durante el crecimiento. Bajo estrés por Cd, todos los genotipos mostraron tolerancia durante el crecimiento. La prolina y los pigmentos fotosintéticos fueron indicadores de tolerancia al estrés salino.; Objective: To evaluate the tolerance of four genotypes of Medicago sativa L. to salinity and cadmium, through the study of germination, growth parameters, photosynthetic pigments, and osmocompatible response. Materials and methods: The experimental design was a completely randomized design with a factorial arrangement: type of genotype: CW 197, Trinidad 87, CW 660 and Salina PV and levels of saline (NaCl) and cadmium (Cl2 Cd) stress. Factorial ANOVA was performed to identify the influence of stress conditions on the measured variables, multiple comparisons analyse of means were performed when a significant effect was found. Twenty seeds were sown in triplicate irrigated with water (control) and solutions between 10 to 200 mM of NaCl and 100 to 500 µM of Cl2 Cd for the germination study. Growth, proline, and photosynthetic pigments were measured in 4-week-old seedlings grown in pots irrigated with nutrient solution (control) and increasing concentrations of NaCl (50-200 mM) and Cl2 Cd (25-100 µM). Results: Under salinity, the CW179 and CW660 genotypes were tolerant to salinity at germination, and the Salina PV and Trinidad 87genotypes were more tolerant during growth. In response to Cd, the genotypes showed tolerance during growth. Proline was osmoprotective against salinity, but not against Cd stress. Photosynthetic pigments decreased with salt stress; however, Cd did not affect them. Conclusion: The CW 660 genotype was the most tolerant to salinity and Cd during germination. It is concluded that the Trinidad 87 and Salina PV genotypes are tolerant to salt and the CW 197 and CW 660 genotypes are sensitive during growth. Under Cd stress, all genotypes showed tolerance during growth. Proline and photosynthetic pigments were indicators of tolerance to salt stress.

Role of iodine recycling on sea‐salt aerosols in the global marine boundary layer

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Role of iodine recycling on sea‐salt aerosols in the global marine boundary layer Li, Qinyi; Tham, Yee Jun; Fernandez, Rafael Pedro; He, Xu-Cheng; Cuevas, Carlos Alberto; Saiz López, Alfonso Heterogeneous uptake of hypoiodous acid (HOI), the dominant inorganic iodine species in the marine boundary layer (MBL), on sea-salt aerosol (SSA) to form iodine monobromide and iodine monochloride has been adopted in models with assumed efficiency. Recently, field measurements have reported a much faster rate of this recycling process than previously assumed in models. Here, we conduct global model simulations to quantify the range of effects of iodine recycling within the MBL, using Conventional, Updated, and Upper-limit coefficients. When considering the Updated coefficient, iodine recycling significantly enhances gaseous inorganic iodine abundance (∼40%), increases halogen atom production rates (∼40% in I, >100% in Br, and ∼60% in Cl), and reduces oxidant levels (−7% in O3, −2% in OH, and −4% in HO2) compared to the simulation without the process. We appeal for further direct measurements of iodine species, laboratory experiments on the controlling factors, and multiscale simulations of iodine heterogeneous recycling.

Una salud en El Molino

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Una salud en El Molino Gamboa, María Inés; Osen, Beatriz Amelia; Butti, Marcos Javier; Corbalán, Valeria Vanesa; Lagala, Fiamma Hebe; Vazzano, M.; Antonini, A.; Barrera, V.; Luna, C.; Acosta, C.; Nigro, J.; Salvador, L.; Barrena, P.; Bonzo, E.; Muller, R. J.; Rodriguez, M.; Ciarmela, L.; Solís, AA; Terminello, J.; Borrelli, Salvador Osvaldo; Gavalda, F.; Urbiztondo, M.; Oliveras Barri, P.; Guzman Loza, A.; Palancar, T.; Trocozo, M. I.; Oliva, D.; Wolcan, S.; Falcone, S.; Palau, G.; Radman, Nilda Ester Las áreas vulnerables están constituidas por urbanizaciones informales, densas, con viviendas precarias, sin acceso a instalaciones sanitarias adecuadas, ocupadas por poblaciones de bajo nivel socioeconómico y educativo (Abaleron, 1995). En estas poblaciones, es común la presencia de parasitosis intes-tinales de elevada intensidad en niños, así como la falta de cuidados de las mascotas por parte de los dueños (Radman y col., 2014).Los caninos suelen alimentarse con desechos y a menudo realizan coprofagia de heces humanas, domésticos favorece la presencia y el mantenimiento de infecciones, reinfecciones y coinfecciones (Gamboa y col., 2009).

Abundance, diversity, and distribution of plant-parasitic nematodes in horticultural soils under different management systems in a tomato-producing area in Argentina

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Abundance, diversity, and distribution of plant-parasitic nematodes in horticultural soils under different management systems in a tomato-producing area in Argentina Salas, Augusto; Barrera, Marcelo Daniel; Achinelly, Maria Fernanda Monitoring the diversity and structure of plant-parasitic nematode (PPN) communities together with developing appropriate control strategies can reduce the occurrence of these pathogens and other plant pests in horticultural crops. In this context a study of the abundance, frequency, diversity and distribution of PPN in horticultural soils under glasshouse conditions from the Green Belt of La Plata, Buenos Aires, Argentina, under different management systems was undertaken. Soil samples were collected from three horticultural areas with different tomato crop managements: agroecological crop (AC); organic crop with Brassicaceae soil amendments (OC); intensive conventional crop treated with methyl bromide (MeBr) (IC). The parameters evaluated were: nematode genera richness (G); Shannon-Wiener diversity index (H') (Hutcheson's t-test was applied for this index); equitability index (E); abundance; and frequency of genera. ANOSIM and SIMPER statistical analyses were performed to find significant differences between the nematode assemblages from the different sites. A total of 14 genera of PPN were identified among the three crop sites. Members of the feeding habits categories ectoparasites, semi-endoparasites, migratory endoparasites and sedentary endoparasites were observed. Statistical analysis enabled us to characterise each site based on the composition of the nematode assemblages. Helicotylenchus, Tylenchus and Nacobbus were the most frequent and abundant genera. AC and OC showed similar values of richness and diversity; the crop treated with MeBr (IC) showed the lowest diversity of PPN.

Sandstone weathering processes in the painted rock shelters of Cerro Colorado (Córdoba, Argentina)

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Sandstone weathering processes in the painted rock shelters of Cerro Colorado (Córdoba, Argentina) Peña Monné, José Luis; Sampietro Vattuone, Maria Marta; Baez, Walter Ariel; García‐Giménez, Rosario; Stábile, Franco Matías; Martínez Stagnaro, Susana Yamila; Tissera, Luis Esteban Tafoni, produced by physicochemical weathering of sandstones, are abundant in the Cerro Colorado (Córdoba province, Argentina). Many of the rock shelters are decorated with rock art of high heritage significance. This art belongs to semisedentary communities from the Late Prehispanic Period (ca. 1550–350 AP). They include morphologies inherited from more humid ancient climates combined with current weathering processes. Evolutionary relief study established that tafoni formation is a product of inherited past wetter climates. Mineralogical and petrographic analyses were performed on samples collected from the sandstones and from various morphologies, weathering residues, and wall and ceiling concretions at four rock shelters, Cueva del Indio, Ricci, Quitilipi, and La Trampa. Gypsum and other salts that are not part of the unaltered rock but the result of weathering reveal the magnitude of hydroclastic and haloclastic processes. These activities form active granular disintegration, flaking, and spalling, and impinge on some painted panels. Mapping the distribution of weathering features and processes at each rock shelter enables the planning of interventions to mitigate and alleviate the effects caused by infiltration of water through rock discontinuities, fractures, and overhangs. It also allows decreasing the accumulation of dust and minimizing muddy water flowing over the paintings. These actions are aimed at retarding the progression of rock art degradation and the visible loss of some paintings.

Escrituras rozitchnerianas del exilio

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Escrituras rozitchnerianas del exilio; Rozitchnerian writings of exile Alfieri, Joaquín El presente trabajo intenta recuperar los escritos elaborados por León Rozitchner durante su exilio en Venezuela durante la última dictadura militar Argentina (1976-1983). Me propongo analizar dichas textualidades a partir de tres enfoques diversos: el exilio como un testimonio; el exilio como un balance; y el exilio como una traición. El artículo aborda cada una de estas perspectivas con el objeto de destacar una de las características fundamentales de la obra del autor argentino: su capacidad por desarrollar una filosofía en relación constante con los índices existenciales y los lazos vitales desde los cuales brota su escritura. El exilio, en este sentido, aparece como un ejemplo paradigmático de esta característica.; This work tries to recover the writings performed by Leon Rozitchner during his exile in Venezuela in the decade of 70s during the last Argentine military dictatorship between (1976-1983). I intend to analyze these texts from three different approaches: exile as a testimony; exile as a balance; and exile as a betrayal. The article addresses each of these perspectives in order to highlight one of the fundamental characteristics of the Argentine author's work: his capacity to develop a philosophy in constant relationship with existential index and vital ties from which writing springs. Exile, in this sense, appears as a paradigmatic example of this characteristic

Presence of the fungus-growing ant Mycetophylax morschi (Hymenoptera, Formicidae) in a valuable area of pampas grassland in a mountainous area in the southeast of Buenos Aires province, Argentina

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Presence of the fungus-growing ant Mycetophylax morschi (Hymenoptera, Formicidae) in a valuable area of pampas grassland in a mountainous area in the southeast of Buenos Aires province, Argentina Arcusa, Juan Manuel; Cicchino, Armando Conrado The genus Mycetophylax belongs to the subfamily Myrmicinae, tribe Attini, and is one of the lesser-known genera of fungus-growing ants. Of the three Mycetophylax species, only M. morschi was cited for Argentina. This species is also well represented in various coastal locations with sandy beaches in eastern Brazil. The present work represents the second record of the species for the Province of Buenos Aires and for Argentina and the first collection record of this species in a grassland placed in a mountainous environment.

El quiebre de la cotidianidad en la niñez chilena exiliada en Mendoza, Argentina (1973-1989)

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El quiebre de la cotidianidad en la niñez chilena exiliada en Mendoza, Argentina (1973-1989); The Breakdown of Everyday Life in Chilean Childhood Exiled in Mendoza, Argentina (1973-1989) Paredes, Héctor Alejandro Este trabajo analizará experiencias de la niñez exiliada a partir de casos encontrados en el archivo del Comité Ecuménico de Acción Social, de la Comisión Católica Argentina de Inmigración CCAI, del Centro de Documentación de la Comisión Chilena de Derechos Humanos de Santiago de Chile y de una entrevista a un militante del Partido Comunista chileno que llegó a Mendoza con 17 años. Indagaremos sobre el impacto en el quiebre de la cotidianidad de la infancia exiliada y nos animaremos a problematizar ciertos mitos como el de la niñez a-militante o el de la persecución de la niñez como consecuencia no planificada por el estado represivo chileno.; This paper will analyze the experiences of childhood exiles based on cases found in the archives of the Ecumenical Committee for Social Action, the Argentine Catholic Commission for Immigration CCAI, the Documentation Center of the Chilean Human Rights Commission of Santiago de Chile and an interview with a member of the Chilean communist party who arrived in Mendoza at the age of 17. We will inquire about the impact on the breakdown of the daily life of exiled children and we will encourage ourselves to problematize certain myths such as that of a-militant childhood or that of the persecution of children as an unplanned consequence of the repressive Chilean state.

Effect of Long-Term Agricultural Management on the Soil Microbiota Influenced by the Time of Soil Sampling

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Effect of Long-Term Agricultural Management on the Soil Microbiota Influenced by the Time of Soil Sampling Fernandez Gnecco, Gabriela Amancay; Covacevich, Fernanda; Consolo, Verónica Fabiana; Behr, Jan H.; Sommermann, Loreen; Moradtalab, Narges; Maccario, Lorrie; Sørensen, Søren J.; Deubel, Annette; Schellenberg, Ingo; Geistlinger, Joerg; Neumann, Günter; Grosch, Rita; Smalla, Kornelia; Babin, Doreen Application of agrochemicals and mechanization enabled increasing agriculturalproductivity yet caused various environmental and soil health-related problems.Agricultural practices affect soil microorganisms, which are the key players of manyecosystem processes. However, less is known about whether this effect differs betweentime points. Therefore, soil was sampled in winter (without crop) and in summer (inthe presence of maize) from a long-term field experiment (LTE) in Bernburg (Germany)managed either under cultivator tillage (CT) or moldboard plow (MP) in combinationwith either intensive nitrogen (N)-fertilization and pesticides (Int) or extensive reducedN-fertilization without fungicides (Ext), respectively. High-throughput sequencing of 16SrRNA gene and fungal ITS2 amplicons showed that changes in the microbial communitycomposition were correlated to differences in soil chemical properties caused by tillagepractice. Microbial communities of soils sampled in winter differed only depending onthe tillage practice while, in summer, also a strong effect of the fertilization intensity wasobserved. A small proportion of microbial taxa was shared between soils from the twosampling times, suggesting the existence of a stable core microbiota at the LTE. Ingeneral, taxa associated with organic matter decomposition (such as Actinobacteria,Bacteroidetes, Rhizopus, and Exophiala) had a higher relative abundance under CT.Among the taxa with significant changes in relative abundances due to different long-termagricultural practices were putative pathogenic (e.g., Gibellulopsis and Gibberella) andbeneficial microbial genera (e.g., Chitinophagaceae, Ferruginibacter, and Minimedusa).In summary, this study suggests that the effects of long-term agricultural managementpractices on the soil microbiota are influenced by the soil sampling time, and this needsto be kept in mind in future studies for the interpretation of field data.

Early Devonian paleogeographic evolution of SW Gondwana (Precordillera Argentina). How can the record of plants help us?

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Early Devonian paleogeographic evolution of SW Gondwana (Precordillera Argentina). How can the record of plants help us? Arnol, Jonatan Ariel; Coturel, Eliana Paula In this work we refer new fossil plant records and revise the systematics of previously described taxa. The finding of Sporogonites excellens and the analysis of its fossil record allows us to propose it as a Lower Devonian indicator. The finding of a leafy lycophyte remains allows us to identify Haskinsia sp. in Precordillera and confirms its presence since the Emsian. From the registry of the plants associations found and taking into account the good age control in the sections to the north of the San Juan river, we propose a Devonian age (pre-Emsian) for the southern region (Banchongo Farm and vicinity). In this way, the Precordillera basin would be separated by a positive structure in at least two depocentres at this time, developing the Talacasto Formation to the north and center of the basin while the deposits of the Punta Negra and Villavicencio Formations occurred simultaneously to the south. During the Emsian- Middle Devonian, the rise in sea level, higher rates of sediment inputs and a marked subsidence made possible the deposition of the Punta Negra formation throughout the basin. The above conclusions affirm the importance of biostratigraphy plant-based in successions that do not have the presence of other markers.

Measurement of linear accelerator spectra, reconstructed from percentage depth dose curves by neural networks

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Measurement of linear accelerator spectra, reconstructed from percentage depth dose curves by neural networks Torres Díaz, Jorge; Grad, Gabriela Beatriz; Bonzi, Edgardo Purpose Linear accelerator (linac) spectra, used to improve the accuracy of dose calculation and to produce a complete description of beam quality, among other aspects, are relevant in radiotherapy and linear accelerator physics. Methods In this work we apply neural networks in solving an ill-conditioned system of linear equations, to indirectly measure the linear accelerator spectra via the percentage depth dose curves. The photon beam spectra are related to radiation doses through a Fredholm integral equation. To address our problem we measured the percentage depth dose curve in water and solved a discretized Fredholm equation using artificial neural network. After analysing the typology of our physical problem we selected a MultiLayer Perceptron Neural Network and designed the most suitable neural network architecture. Results The reconstructed spectra were compared with spectra from three linacs, two of them obtained by us through simulations and the third produced by another author, achieving a concordance between 92 % and 96 %. Therefore, the spectrum of any accelerator can be quickly and easily reconstructed from measured percent depth dose curves, applying a trained artificial neural network.

New Synthetic Caffeine Analogs as Modulators of the Cholinergic System

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New Synthetic Caffeine Analogs as Modulators of the Cholinergic System Fabiani, Camila; Biscussi, Brunella; Munafó, Juan Pablo; Murray, Ana Paula; Corradi, Jeremias; Antollini, Silvia Susana Alzheimer´s disease is a multifactorial neurodegenerative disorder. Since cholinergic deficit is amajor factor in this disease, twomolecular targets for its treatment are the acetylcholinesterase (AChE) and the nicotinic acetylcholine receptors (nAChRs). Given that caffeine is a natural compound that behaves as an AChE inhibitor and as a partial agonist of nAChRs, the aim of this work was to synthetize more potent bifunctional caffeine analogs that modulate these two molecular targets. To this end, a theophylline structure was connected to a pyrrolidine structure through a methylene chain of different lengths (3 to 7 carbon atoms) to give compounds 7-11. All caffeine derivatives inhibited the AChE, of which compound 11 showed the strongest effect. Electrophysiological studies showed that all compounds behave as agonists of the muscle and the neuronal a7 nAChR with greater potency than caffeine. To explore whether the different analogs could affect the nAChR conformational state, the nAChR conformational-sensitive probe crystal violet (CrV) was used. Compounds 9 and 10 conduced the nAChR to a different conformational state comparable with a control nAChR desensitized state. Finally, molecular docking experiments showed that all derivatives interacted with both the catalytic and anionic sites of AChE and with the orthosteric binding site of the nAChR. Thus, the new synthetized compounds can inhibit the AChE and activatemuscle and a7 nAChRs with greater potency than caffeine, which suggests that they could be useful leaders for the development of new therapies for the treatment of different neurologic diseases.

Dual Control Structure of Modular Multilevel Converters for Power System Support

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Dual Control Structure of Modular Multilevel Converters for Power System Support Leon, Enrique Andres; Freytes, Julian This paper presents an analysis of two philosophies to control the modular multilevel converter (MMC). Most MMC control strategies are based on the philosophy used in the traditional voltage-source converter, in which the dc-bus voltage is controlled through the ac-side power; this approach is referred to here as the classical control approach. Because the MMC has an additional degree of freedom, an alternative control philosophy has recently been proposed, in which the dc-bus voltage is controlled through the dc-side power. In this paper, a comparison of these control approaches is presented and their main differences are described. Considering the increasing requirements imposed by system operators to converter-interfaced systems, guidelines are also given to provide supplementary services such as virtual inertia provision, short-term frequency support, virtual capacitor emulation, and oscillation damping. The provided insights are useful for selecting the appropriate MMC control strategy and for developing new supplementary controls for facilities based on the MMC topology.

Biobased polyester from soybean oil: Synthesis, characterization and degradation studies

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Biobased polyester from soybean oil: Synthesis, characterization and degradation studies Bernard, Mariana Del Valle; Nicolau, Veronica Viviana; Strumia, Miriam Cristina Industrially used polymers derived from fossil fuels have a negative environmental impact when being disposed of. They could be efficiently replaced by natural polymers, which are potentially degradable and which can match or even surpass them in mechanical performance. In this work, a rigid thermosetting polymer is obtained by copolymerization of maleinated acrylated epoxidized soybean oil (MAESO) with styrene (St). MAESO is synthetized by epoxidation, acrylation and maleinization from industrial soybean oil (SO). Resin characterization is performed using FT-IR,1H NMR and SEC, while copolymer characterization includes a mechanical test, degradation test and SEM. The aim of this work is the replacement of unsaturated polyester (UP) and the optimization of the SO modification reaction in MAESO. The replacement of UP by 25, 50 and 100% of MAESO enables improvements in the mechanical properties. Additionally, it is assessed whether the replacement of UP by MAESO is enough to improve the degradation properties, and the effect of degradation on the mechanical properties is analyzed. MAESO-St copolymers improve the degradation process in relation to UP, and 240 days of in vitro degradation in the presence of Aspergillus niger and Alternaria alternata fungi causes cracks, surface damage and changes in the mechanical properties of the degraded copolymer.

Response of inflorescence structure and oil yield components to source-sink manipulation by artificial shading in olive

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Response of inflorescence structure and oil yield components to source-sink manipulation by artificial shading in olive Trentacoste, Eduardo; Calvo, Franco Emmanuel; Sánchez, Cecilia L.; Calderón Diaz, Facundo Javier; Banco, Adriana Pamela; Lémole, Georgina Olive yield components are first determined during flowering, ovary growth, and fruit set. However, variations of the assimilates available during these important processes have been little studied. The aims of this study were to evaluate the effects of source-sink alterations on (i) production of flowers and their structure, (ii) sink responsiveness source activity, and (iii) the relationship between final fruit mass and flower ovary size. Two levels of shading at 50% and 80% were applied in an orchard cv. Arbequina over three seasons, with two durations: short-period (SP, from harvest up to 20 days after flowering) and long-period (LP, continuous shading from beginning to end of the experimental period). An unshaded Control was included. Control presented the highest fruit yield and was 50% greater than both SP50-LP50, and 80% greater than both SP80-LP80. Fruit number was highly responsive to source-sink alterations. The control and both SP50-LP50 treatments presented similar fruit loads, whereas both SP80-LP80 produced 80% less fruits. Source activity alteration during pre-fruit set affected inflorescence structure. By contrast, during the post-fruit set, it drastically reduced inflorescence production. Fruit mass increased mainly due to fruit growth rate in relation to the assimilate. Reduction in ovary mass due to low source activity during pre-fruit set had a slight influence on final fruit mass when source activity was not limited during the post-fruit set period. Fruit oil concentration was highly conservative across a wide range of source-sink ratios.

¿Son todas iguales?

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¿Son todas iguales? García Beaudoux, Virginia Inés Se suele afirmar, sin mayor sustento probatorio, que existe “un estilo de liderazgo femenino”, que se caracteriza por el predominio de habilidades blandas tales como la empatía y la inteligencia interpersonal, así como por un bajo grado de personalización en la toma de decisiones y en la comunicación. En este artículo se cuestionan tales afirmaciones sobre la base de los resultados de una investigación llevada a cabo sobre la comunicación de sus liderzgos efectuada en Instagram por una muestra de catorce mujeres que ocupan cargos politicos ejecutivos electivos.

Penetration enhancers for the development of intranasal formulations for use in equines

CONICET Digital -

Penetration enhancers for the development of intranasal formulations for use in equines Velloso, María Inés; Landoni, Maria Fabiana The aim of this review is to assess penetration enhancers, such as cyclodextrins, chitosan and their derivatives, surfactants, bileacids, their salts and derivatives, sodium taurodihidrydrofusidate, and phospholipids used in the development of intranasalformulations with a potential application in horses. In the last few years, the interest in the intranasal administration routein humans has grown because it is bloodless, noninvasive, and painless and represents a direct path toward the centralnervous system. However, in equine medicine, the use of this administration route is scarce. Since equines have a nasal cavitywith large surface area and blood irrigation, a high bioavailability of intranasal administered drugs is expected. Nowadays,the development of formulations for intranasal administration in equines is a challenge. The present review proposes theassessment of the characteristics and potential effects of the most important penetration enhancers in the development ofintranasal formulations for use in equines.

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