Robust Molecular Anodes for Electrocatalytic Water Oxidation Based on Electropolymerized Molecular Cu Complexes Amthor, Sebastian; Ranu, Koushik; Bellido, Carlos G.; Salomón, Fernando Federico; Piccioni, Alberto; Mazzaro, Raffaello; Boscherini, Federico; Pasquini, Luca; Gil Sepulcre, Marcos; Llobet, Antoni A multistep synthesis of a new tetra-amidate macrocyclic ligand functionalized with alkyl-thiophene moieties, 15,15-bis(6-(thiophen-3-yl)hexyl)-8,13-dihydro-5H-dibenzo[b,h][1,4,7,10]tetraazacyclotridecine-6,7,14,16(15H,17H)-tetraone, H4L, is reported. The reaction of the deprotonated ligand, L4−, and Cu(II) generates the complex [LCu]2−, that can be further oxidized to Cu(III) with iodine to generate [LCu]−. The H4L ligand and their Cu complexes have been thoroughly characterized by analytic and spectroscopic techniques (including X-ray Absorption Spectroscopy, XAS). Under oxidative conditions, the thiophene group of [LCu]2− complex polymerizes on the surface of graphitic electrodes (glassy carbon disks (GC), glassy carbon plates (GCp), carbon nanotubes (CNT), or graphite felts (GF)) generating highly stable thin films. With CNTs deposited on a GC by drop casting, hybrid molecular materials labeled as GC/CNT@p-[LCu]2− are obtained. The latter are characterized by electrochemical techniques that show their capacity to electrocatalytically oxidize water to dioxygen at neutral pH. These new molecular anodes achieve current densities in the range of 0.4 mA cm−2 at 1.30 V versus NHE with an onset overpotential at ≈250 mV. Bulk electrolysis experiments show an excellent stability achieving TONs in the range of 7600 during 24 h with no apparent loss of catalytic activity and maintaining the molecular catalyst integrity, as evidenced by electrochemical techniques and XAS spectroscopy.

Melanoma cells with acquired resistance to vemurafenib have decreased autophagic flux and display enhanced ability to transfer resistance Perez, Celia Noemí; Falcón, Cristian Roberto; Delgado Mons, Johinna Ileana; Cuello Orlandi, Federico; Sangiacomo, Mercedes; Fernandez Muñoz, Juan Manuel; Guerrero, Martín; Benito Rodriguez, Paula Guadalupe; Colombo, Maria Isabel; Zoppino, Felipe Carlos Martin; Alvarez, Sergio Eduardo Over the last years, the incidence of melanoma, the deadliest form of skin cancer, has risen significantly. Nearly half of the melanoma patients exhibit the BRAFV600E mutation. Although the use of BRAF and MEK inhibitors (BRAFi and MEKi) showed an impressive success rate in melanoma patients, durability of response remains an issue because tumor quickly becomes resistant. Here, we generated and characterized Lu1205 and A375 melanoma cells resistant to vemurafenib (BRAFi). Resistant cells (Lu1205R and A375R) exhibit higher IC50 (5–6 fold increase) and phospho-ERK levels and 2–3 times reduced apoptosis than their sensitive parents (Lu1205S and A375S). Moreover, resistant cells are 2–3 times bigger, display a more elongated morphology and have a modulation of migration capacity. Interestingly, pharmacological inhibition of sphingosine kinases, that prevents sphingosine-1-phosphate production, reduces migration of Lu1205R cells by 50 %. In addition, although Lu1205R cells showed increased basal levels of the autophagy markers LC3II and p62, they have decreased autophagosome degradation and autophagy flux. Remarkably, expression of Rab27A and Rab27B, which are involved in the release of extracellular vesicles are dramatically augmented in resistant cells (i.e. 5–7 fold increase). Indeed, conditioned media obtained from Lu1205R cells increased the resistance to vemurafenib of sensitive cells. Hence, these results support that resistance to vemurafenib modulates migration and the autophagic flux and may be transferred to nearby sensitive melanoma cells by factors that are released to the extracellular milieu by resistant cells.

A Stochastic Detection Models Comparison in Turbulent Flow Events Calandra, Maria Valeria; Marañon Di Leo, Julio The need to establish the downwind fluid dynamic field of aerodynamic bodies subjected to a givenvelocity field is well known, to verify their aerodynamic characteristics. In this context, differenttechniques allow us to establish the characteristics of the field. It is almost always necessary to carry out quantitative determinations to describe the field correctly, particularly when the field is made up of turbulent wakes. In this sense, in the experimental field, it is common to use hot-wire anemometry techniques, which have great capabilities to quantify high-frequency events. Previous work has analyzed the determination of changes in hot-wire anemometry signals for the detection of events in turbulent flows with different models, based on stochastic algorithms (CPM - Change Point Model).The present work aims to compare the results obtained previously with the application of different CPM models developed. Previously applied and evaluated measurements are used, the implementation of the models is carried out and the results are compared. All the algorithms used can detect changes in data that do not have a known distribution, i.e. non-parametric distributions, which are typical for turbulent flow field signals. Measurements of the fluctuating components of the wind tunnel velocity at a specific point are considering. The signals used correspond to periodic detachments downstream of a flow control device (Gurney mini-flap) at the trailing edge of an airfoil. The results show which are the best models to use for the experimental detection of such turbulent events in the flow field.

Aspectos ecológicos parasitarios en Pleurodema nebulosum (Anura: Leptodactylidae) en la región del monte, San Juan, Argentina; Parasitic ecological aspects in Pleurodema nebulosum (Anura: Leptodactylidae) in the monte region, San Juan, Argentina Castillo, Gabriel Natalio; González Rivas, Cynthia Jesica; Acosta, Juan Carlos Pleurodema nebulosum es una especie con amplia distribución en Argentina. Se analizó el parasitismo y su relación con el sexo, perturbación humana, masa y tamaño corporal. Se identificó al nemátodo Aplectana nebulosa (Cosmocercidae) en el intestino largo. Encontramos que la abundancia media parasitaria se asoció positivamente con el tamaño (longitud hocico-cloaca), sexo macho y perturbación humana. Un mayor tamaño corporal condujo a un aumento de la abundancia media de parásitos. Los machos de ambos ambientes estaban más parasitados que hembras. La abundancia media de parásitos fue mayor en el ambiente perturbado en comparación con el control. Discutimos nuestros resultados en un contexto ecológico. Se provee información novedosa sobre el parasitismo en esta especie de anfibio en el desierto del monte de Argentina.; Pleurodema nebulosum is a species with a wide distribution in Argentina. Parasitism and its relationship with host sex, human disturbance, and body mass were assessed. The nematode Aplectana nebulosa (Cosmocercidae) was identified in the large intestine. Mean parasitic abundance was found to be positively associated with size (snout-vent length), male sex and human disturbance. Larger body size led to an increase in the mean abundance of parasites. Males in both environments were more parasitized than females. The mean abundance of parasites was higher in the disturbed environment compared to the control. We discuss our results in an ecological context. Novel information is provided on parasitism in this amphibian species in the Monte Desert, Argentina.

Novel Fluoroquinolones with Possible Antibacterial Activity in Gram-Negative Resistant Pathogens: In Silico Drug Discovery Coba Males, Manuel Alejandro; Lavecchia, Martín José; Alcívar León, Christian David; Santamaría Aguirre, Javier Antibiotic resistance is a global threat to public health, and the search for new antibacterial therapies is a current research priority. The aim of this in silico study was to test nine new fluoroquinolones previously designed with potential leishmanicidal activity against Campylobacter jejuni, Escherichia coli, Neisseria gonorrhoeae, Pseudomonas aeruginosa, and Salmonella typhi, all of which are considered by the World Health Organization to resistant pathogens of global concern, through molecular docking and molecular dynamics (MD) simulations using wild-type (WT) and mutant-type (MT) DNA gyrases as biological targets. Our results showed that compound 9FQ had the best binding energy with the active site of E. coli in both molecular docking and molecular dynamics simulations. Compound 9FQ interacted with residues of quinolone resistance-determining region (QRDR) in GyrA and GyrB chains, which are important to enzyme activity and through which it could block DNA replication. In addition to compound 9FQ, compound 1FQ also showed a good affinity for DNA gyrase. Thus, these newly designed molecules could have antibacterial activity against Gram-negative microorganisms. These findings represent a promising starting point for further investigation through in vitro assays, which can validate the hypothesis and potentially facilitate the development of novel antibiotic drugs.

Cosmogenic nuclide moraine chronologies from Patagonia: A globally synchronic response of mountain glaciers during Termination 1? Soteres, Rodrigo L.; Sagredo, Esteban; Kaplan, M.R.; Martini, Mateo Antonio; Riquelme, Fabian; Schaefer, J.M. Surface-exposure dating of moraines reveals that Patagonian glaciers fluctuated at the pulsebeat mimicked in polar ice cores from both hemispheres. These findings favor hypotheses that invoke coupled oceanic–atmospheric drivers to generate and propagate millennial-scale climate shifts during Termination 1.

Estrogens receptors, nuclear coactivator 1 and ligand-dependent corepressor expression are altered early during induced ovarian follicular persistence in dairy cattle Notaro, Ulises Sebastián; Huber, Emilia; Stassi, Antonela Florencia; Ormaechea, Nadia Estefanía; Chiaraviglio, Juan Alberto; Baravalle, María Eugenia; Ortega, Hugo Hector; Rey, Florencia; Salvetti, Natalia Raquel Failure of ovulation can lead to follicular persistence, one of the main components of the pathogenesis of cystic ovarian disease (COD) in dairy cattle. Follicular persistence causes the permanence of a functional follicular structure in the ovary, which alters the cyclicity of the female and causes infertility. The aim of the present study was to evaluate the expression of estrogen receptors (ESR) 1 and 2, and the coregulatory proteins NCOA1, NRIP1 and LCOR by immunohistochemistry, in antral and preovulatory/persistent follicles in a model of follicular persistence induced by low levels of progesterone, to detect incipient changes during COD development, on the expected day of ovulation (P0) and after 5 (P5), 10 (P10) and 15 (P15) days of follicular persistence. Twenty-five Holstein cows were used, which were distributed in 5 groups: control group (n = 5), group P0 (n = 5), group P5 (n = 5), group P10 (n = 5), group P15 (n = 5). ESR1 expression was lower in antral follicles of the P5 (theca), P10 and P15 (theca and granulosa) groups relative to the control group (p < 0.05), and also lower in granulosa cells of persistent follicles of the P5, P10 and P15 groups than in dominant follicles of the control group (p < 0.05), without differences in theca cells. ESR2 expression showed no differences between groups. The ESR1:ESR2 balance favored ESR2 expression along the development of persistent follicles, as from 5 days of persistence (p < 0.05). NCOA1 expression was higher in granulosa cells of both antral and persistent follicles from the P0 group relative to the P5 and P10 groups, but showed no differences with the control and P15 groups (p < 0.05). Theca cells of antral and persistent follicles showed higher expression in the P0 and P15 groups in relation to the control, P5 and P10 groups (p < 0.05). No differences were detected for NRIP1 in antral, dominant and persistent follicles between groups. LCOR expression showed a decrease in granulosa cells of antral follicles from all persistence groups relative to the control group (p < 0.05). In theca cells, antral follicles of the P10 group showed lower LCOR expression than the control group (p < 0.05). LCOR expression was similar for dominant and persistent follicles. Considering that the ESR1:ESR2 balance favored ESR2 expression along the development of persistent follicles, as well as the decreased LCOR and NCOA1 expression, we may assume that, at the early stages of persistence, there is a negative regulation of ESR transcription. This coincides with the effects of estrogens through ESR on proliferation and apoptosis among other processes that favor follicular persistence. The results obtained provide relevant information in the knowledge of local events during the development of follicular persistence that could explain the failures in the reversion of the disease through hormonal treatments and the high recurrence rates reported for COD. In addition, it contributes to the study and identification of possible therapeutic targets, for the design of new treatments.

Harmonic almost complex structures on almost abelian Lie groups and solvmanifolds Andrada, Adrián Marcelo; Tolcachier, Alejandro An almost abelian Lie group is a solvable Lie group with a codimension one normal abelian subgroup. We characterize almost Hermitian structures on almost abelian Lie groups where the almost complex structure is harmonic with respect to the Hermitian metric. Also, we adapt the Gray–Hervella classification of almost Hermitian structures to the family of almost abelian Lie groups. We provide several examples of harmonic almost complex structures in different Gray–Hervella classes on some associated compact almost abelian solvmanifolds.

Desarrollo de herramientas cuantitativas para asistir en la toma de decisiones médicas relacionadas a discapacidades motrices Catalfamo Formento, Paola Andrea Lucia; Bonell, Claudia Edith; Aldonate, Julio Alberto; Barrera, Verónica; Cherniz, Analía Soledad; Dutto, Cecar; García Añino, Eloisa; Merino, Gabriela Alejandra; Muñoz Larrosa, Eugenia Soledad; Ravera, Emiliano Pablo; Riveras, Mauricio Se define como discapacidad motriz a la disminución total o parcial de la movilidad en uno o más miembros del cuerpo. Las personas realizan tratamientos de rehabilitación motriz para su reinserción activa a la sociedad. Para evaluar el resultado de los tratamientos se requieren de herramientas objetivas, confiables, reproducibles y tecno-lógicamente accesibles para las instituciones de salud de la región. El objetivo de este trabajo fue desarrollar herramientas cuantitativas de la ingeniería que cumplan con estos requisitos.Para ello se estudiaron herramientas de análisis del movimiento humano, tales como parámetros espacio-temporales, despeje mínimo del pie, índices de gasto energético y método de análisis de presiones plantares. Además, para facilitar la implementación de herramientas en los ámbitos clínicos, se desarrollaron softwares que permiten el cálculo automático de los parámetros. Finalmente, se diseñaron e implementaron protocolos de análisis del movimiento humano en centros regionales dedicados a la rehabilitación motriz.Los resultados de este proyecto muestran que es posible desarrollar herramientas basadas en la cuantificación de parámetros biomecánicos y fisiológicos, provistas desde los distintos campos de la ingeniería biomédica, que resultan objetivas, confiables, reproducibles y tecnológicamente accesibles para las instituciones de salud de la región.

Redes de conocimiento en relación a agendas endógenas como alternativa a la tensión internacional-local; Knowledge networks in relation to endogenous agendas as an alternative to international-local tension Oregioni, María Soledad; Avondet, Laura; Durán, María Sol La ciencia y la tecnología han ganado relevancia en las agendas de política pública en la medida en que se las reconoce como componentes imprescindibles de cualquier estrategia que pretenda hacer frente a «desafíos actuales», muchos de los cuales son definidos como tales por los países del Norte global. Posicionadas desde el Sur global, y bajo el entendimiento de la no neutralidad de los conocimientos, indagamos sobre dinámicas de producción de conocimiento y nos cuestionamos si las temáticas en agenda responden a problemáticas situadas. El presente trabajo muestra cómo, a partir de la identificación de una problemática concreta –la producción de cannabis medicinal– fue posible generar redes de cooperación sur-sur formales e informales, integradas por diferentes actores (territoriales e inter-nacionales) en las que se habilitaron nuevas dinámicas de producción de conocimiento a partir de la convergencia de diferentes tipos de saberes y actores. Específicamente, se analizó como caso de estudio la producción de conocimiento sobre cannabis medicinal en la Universidad Nacional del Centro de la Provincia de Buenos Aires (UNICEN). Los resultados de la investigación permiten entender a la universidad como un actor fundamental en la producción de conocimiento y nos muestran cómo, a partir de una de sus funciones, la extensión, es posible crear nuevas dinámicas integrales de internacionalización en producción de conocimiento, destacando la importancia de las redes de cooperación sur-sur a la hora de dar respuesta a la tensión internacional-local en producción de conocimiento.; Science and technology have gained relevance in public policy agendas to the extent that they are recognized as essential components of any strategy that seeks to face «current challenges», many of which are defined as such by the countries of the global north. Positioned from the global South, and under the understanding of the non-neutrality of knowledge, we investigate the dynamics of knowledge production and question whether the topics on the agenda respond to situated problems. This paper shows how, based on the identification of a specific problem –the production of medical cannabis– it was possible to generate formal and informal South-South cooperation networks, made up of different actors (territorial and international) in which new dynamics of knowledge production from the convergence of different types of knowledge and actors. Specifically, the production of knowledge on medicinal cannabis at the National University of the Center of the Province of Buenos Aires (UNICEN) was analyzed as a case study. The results of the research allow us to understand the university as a fundamental actor in the production of knowledge; and they show us how from one of its functions, extension, it is possible to create new integral dynamics of internationalization in knowledge production, highlighting the importance of South-South cooperation networks when responding to tension international-local knowledge production.

How effective is camera trapping in monitoring grassland species in the southern Pampas ecoregion?; ¿Qué tan efectivo es el fototrampeo para el monitoreo de especies de pastizal en el sur de la ecorregión Pampas? Trofino Falasco, Clara; Simoy, Maria Veronica; Aranguren, Maria Florencia; Pizzarello, María Gimena; Cortelezzi, Agustina; Vera, David Gustavo; Simoy, Mario Ignacio; Marinelli, Claudia Beatriz; Cepeda, Rosana Esther; Di Giacomo, Adrian Santiago; Berkunsky, Igor We assessed the efficiency of camera trapping in monitoring bird and mammal species in the grasslands of Tandilia Mountains by calculating the naïve occupancy, capture rate, and time to the first detection for each species. We compared the observed richness with the reported richness from online databases. We performed species accumulation curves to estimate the sampling effort necessary to detect bird and mammal species. We detected 50 bird and 15 mammal species. The top 5 bird species (Chalk-browed Mockingbird, Rufous-collared Sparrow, Rufous Hornero, Great Pampa-Finch, and Spotted Nothura) accounted for 48% of all detected individual birds, with naïve occupancy of 21-25% and mean times for the first detection between 6 and 9 days. The top 5 mammal species (Pampas fox, large hairy armadillo, European hare, Molina’s hog-nosed skunk, and Geoffroy’s cat) accounted for 81% of all detected individual mammals, with naïve occupancy of 32-77% and mean times for the first detection between 4 and 7 days. A sampling effort of 2 weeks was the optimal balance between effort and result qualities. We detected all the reported richness of mammals and half of the reported grassland-associated birds. We provide valuable information for future grassland species monitoring with camera trapping in Neotropical grasslands.; Evaluamos la eficiencia del fototrampeo para monitorear aves y mamíferos en pastizales del sistema de Tandilia mediante la ocupación naïve, tasa de captura y tiempo hasta la primera detección de cada especie. Comparamos la riqueza observada con aquella reportada en bases de datos en línea. Realizamos curvas de acumulación de especies para estimar el esfuerzo de muestreo necesario para detectar la riqueza de especies. Detectamos 50 especies de aves y 15 de mamíferos. Las principales especies de aves (calandria común, chingolo, hornero, verdón e inambú campestre) representaron 48% de todas las detecciones de este grupo, con una ocupación naïve de 21-25% y tiempos promedios hasta la primera detección de entre 6 y 9 días. Las principales especies de mamíferos (zorro pampeano, peludo, liebre europea, zorrino y gato montés) contituyeron 81% de las detecciones de este grupo, con una ocupación naïve de 32- 77% y tiempos promedios hasta la primera detección de entre 4 y 7 días. Un muestreo de 2 semanas fue el balance óptimo entre esfuerzo y calidad de los resultados. Se detectó toda la riqueza reportada de mamíferos y la mitad de las aves asociadas a pastizales. Brindamos información valiosa para futuros monitoreos con fototrampeo en pastizales neotropicales.

Prediction of the physico-chemical properties of vegetable oils using optimal non-linear polynomials Alviso, Dario; Aguerre, Horacio Javier; Nigro, Norberto Marcelo; Artana, Guillermo Osvaldo Vegetable oils (VOs) comprise 90%–98% triglycerides (three fatty acids esters and glycerol), with trace amounts of mono-glycerides and di-glycerides. The content of glycerides in VOs can vary depending on the specific type of oil, the processing methods used, and other factors such as the cultivar and harvest date. VOs have been examined for usage in different applications due to their physicochemical properties, including stationary engines, big ships, and Diesel engines of low and medium speed. There are around 350 VOs that have the potential to be used as fuel sources, the vast majority of which have yet to have their physicochemical properties investigated. Regression models based purely on VOs fatty acid content are beneficial in this context. This study conducts a regression analysis of VOs density (DE), kinematic viscosity (KV), flash point (FP), and low and high heating values (LHV and HHV) as a function of their fatty acids. Several experimental databases were selected, including the values of VOs fatty acid composition and physico-chemical properties. Optimal non-linear polynomials were chosen for the regression procedure. Scheffé polynomials offer different fitting alternatives to adjust the VOs experimental databases using their five main fatty acids: from simple linear polynomials (including five terms) to full cubic polynomials (including 35 terms). The polynomials are validated by showing how well their results correspond with the experimental databases. The standard error values for the proposed full polynomials concerning the databases for DE, KV, FP, LHV, and HHV are 0.70%, 7.79%, 7.86%, 1.66%, and 0.19%, respectively.

Abordaje de la figura de Joaquín Víctor González a partir del análisis del patrimonio histórico cultural de la finca Samay Huasi (Chilecito, La Rioja); Approach to the Figure of Joaquín Víctor González from the Analysis of the Historical Cultural Heritage of the Samay Huasi Farm (Chilecito, La Rioja) Oliva, Camila; Sempe, Maria Carlota; Oliva, Fernando Walter Pablo A partir del estudio del patrimonio histórico y cultural de la Finca Samay Huasi -localizada en el distrito de San Miguel, municipalidad de Chilecito, La Rioja- analizamos la figura de Joaquín Víctor González, ilustre político, jurista educador y masón, cuyo accionar impactó profundamente en la conformación moderna de las instituciones del Estado argentino. Para ello partimos del estudio del patrimonio histórico y cultural de la Finca Samay Huasi propiedad de la Universidad Nacional de La Plata, ubicada en el distrito de San Miguel del departamento Chilecito, La Rioja. Los bienes culturales presentes en la misma poseen un importante valor patrimonial, material e inmaterial, sobre cuyos significados ahondamos en este escrito, para lo cual relevamos monumentos, placas y soportes conmemorativos emplazados en el predio, considerados como soportes de su memoria e identidad. Aquí presentamos su análisis y el de su obra escrita, así como los homenajes y artículos que trataron su figura, realizados por sus contemporáneos y generaciones posteriores. Su finca Samay Huasi, donada en vida a la Universidad Nacional de La Plata representa un patrimonio histórico, administrado por esta institución desde 1941. Esperamos que los resultados aquí expuestos aporten a la puesta en valor del patrimonio existente en la finca y a la apropiación de ese conocimiento por parte de la comunidad local.; From the study of the cultural historical heritage of Finca Samay Huasi, in the district of San Miguel, municipality of Chilecito, La Rioja, we analyze the figure of Joaquin Victor Gonzalez, illustrious politician, jurist, educator and freemason, whose actions profoundly affected the modern conformation of the institutions of the Argentine State. For this, we start from the study of the historical and cultural heritage of the Samay Huasi Farm owned by the National University of La Plata, located in the district of San Miguel of the Chilecito department, La Rioja. The cultural goods present in it have an important patrimonial, material and intangible value, on whose meanings we delve into in this writing, for which we relieve monuments, plaques and commemorative supports located on the property, considered as supports of their memory and identity. Here we present his analysis and that of his written work, as well as the tributes and articles that dealt with his figure, made by his contemporaries and later generations. His farm Samay Huasi, donated in life to the National University of La Plata represents a historical heritage, administered by this institution since 1941. We hope that the results presented here will contribute to the enhancement of the existing heritage on the farm and the appropriation of that knowledge by the local community.

Alteración térmica de artefactos líticos durante el Holoceno medio: Análisis de los conjuntos de Casa del Minero 1, Meseta Central de Santa Cruz; Thermal alteration of lithic artifacts during the middle Holocene: Analyses of the assemblages from Casa del Minero 1, Central Plateau of Santa Cruz Frank, Ariel David En este trabajo analizo los conjuntos líticos termoalterados de la unidad 3 superior de Casa del Minero 1 (Santa Cruz, Argentina), correspondiente al Holoceno medio. Investigo si se aplicó tratamiento térmico durante talla lítica y comparo los hallazgos con aquellos de los componentes finipleistocénicos del sitio. También estudio si otros procesos termoalteraron los conjuntos. Para ello, analizo la ubicación de los indicadores de termoalteración dentro de cada pieza, las características tecnomorfológicas de los artefactos y su distribución en la cueva.Los resultados indican que se aplicó el tratamiento térmico previo al retoque, durante la formatización final de instrumentos. Este procedimiento tendría características distintas a lo registrado para los componentes finipleistocénicos en términos de tipo de materia prima empleada y secuencias operativas en las cuales se implementó, con un uso menos frecuente que en momentos previos. Por otro lado, un grupo de artefactos pudo dañarse térmicamente por la acción de fuegos encendidos con posterioridad a la ocupación o bien por la caída accidental en fogones. No obstante, distintos procesos postdepositacionales habrían alterado la distribución de los restos y/o la conservación de las estructuras de combustión.; In this paper I study the thermally modified lithic assemblages from stratigraphic unit Upper 3, Casa del Minero 1 site (Santa Cruz, Argentina) which dates to the middle Holocene. I analyze if heat treatment was applied during flintknapping, and I compare the results with those obtained from the final Pleistocene layers of the site. I also study if other thermal processes have altered the assemblages. To achieve these goals, I analyze the location of thermal alteration traits within each artifact, the techno-morphological characteristics of the archaeological remains and their distribution within the cave. Results show that heat treatment was applied during the final shaping of tools, before retouch. This procedure had different characteristics to what has been recorded for the final Pleistocene layers, in terms of the kind of raw material used and the chaine operatoire in which it was applied. Furthermore, the use of heat treatment was less frequent during the middle Holocene. Apart from that, a group of artifacts could have become thermally damaged due to the action of fires lit after the occupation or else due to the accidental fall of lithics inside the hearths. However, different post-depositional processes might have modified the distribution of the remains and/or the conservation of the combustion structures.

Electrochemical studies on β-carbolines alkaloids: Kinetics of irreversible oxidation processes Madriz Ruiz, Lorean Mercedes; Cabrerizo, Franco Martín; Vargas Balda, Ronald Eduardo The comprehension of the kinetic processes involved in redox reactions with alkaloids such as β-carbolines (βCs) is crucial to unveil differences in the reactivity of these substances. To this end, electrochemical studies on a screen-printed carbon electrode were conducted, revealing the irreversible nature of the process associated with the first oxidation step of norharmane (nHo), harmine (Ha), harmaline (Hlina), harmol (Hol), and harmalol (Hlol). Results from chronoamperometric (CA) studies indicated that in all cases, the oxidation follows a first order reaction. Additionally, cyclic voltammetry (CV) enabled the estimation of the number of electrons transferred (n) as well as the charge transfer coefficient (αa). Finally, square wave voltammetry (SWV) allowed the investigation of the irreversible nature of the oxidative transformations, determining the oxidation potential (EOx) values, and elucidating of the dependency of the frequency-normalized peak current (ip/f) with the frequency (f). For the first time, the rate constant (k) for the selected βCs was determined from the maximum observed in the ip/f vs. f plot. By correlating Ln(k) with EOx values, a linear free energy relationship that show the relevance of molecular structure in reaction pathways was revealed, which constitutes the novelty of this work. These findings are discussed in the context of other redox processes involving βC alkaloids.

First identification of plant remains in earthen architecture of Argentina: constructive and domestic archaeological data from early colonial contexts (16th and 17th centuries) Castillón, Vanina Gisele; Lopez, María Laura; Igareta, Ana Teresa; Capparelli, Aylen This paper analyses, from an archaeological and ethnobotanical perspective, the botanical remains recovered from earthen architecture of Ibatín and Esteco I/II sites, ruins of the first cities established and depopulated in North-western Argentina along the Spanish advance during the 16th and 17th centuries. Sampling procedure, processing of the sediments and identification of botanical macro and microremains, predominantly opal silica phytoliths, were carried out on the basis of standard methodology to identify botanical remains. Diatoms and microcharcoals were also recorded. Additionally, ethnobotanical research was conducted in order to obtain data from local inhabitants related to traditional earth construction techniques and vegetable fibres used in the process. The integration of the results obtained from both approaches allowed us to generate some proposals regarding the techniques for obtaining and using the plants used in the construction activity and associated practices in the region during the colonial period.

Meat Quality Traits in Beef from Heifers: Effect of including Distiller Grains in Finishing Pasture-Based Diets Merayo, Manuela; Pighín, Darío Gabriel; Cunzolo, Sebastian Abel; Veggetti, Mariela Iris; Soteras, Trinidad; Chamorro, Veronica Celeste; Pazos, Adriana Alejandra; Grigioni, Gabriela Maria Distiller grains (DG), which are the by-product from the bioethanol industry, represent an interesting alternative as animal feedstock. To our knowledge, little information is available on the inclusion of DG on the quality of meat from pasture-fed heifers. Thus, the aim of the present study was to evaluate the effect of DG inclusion in pasture-based systems on the main meat quality attributes of Charolais x Aberdeen Angus heifers. For this purpose, meat from heifers fed with a pasture-based diet without supplementation (P) or with 0.75% of live weight DG supplementation (PDG; DG plus dry-rolled corn, 50:50) or with 0.75% of live weight dry-rolled corn supplementation (PRC) was evaluated. Physical (pH, WHC, color, texture), sensory and nutritional (fat content, fatty acid, and amino acid profile) attributes were evaluated in beef samples. No effect of supplementation was observed on meat pH or color (p > 0.05). Meat from PDG heifers showed higher values of WBSF than meat from P heifers (p = 0.039). However, the overall tenderness evaluated by trained panelists showed no differences due to supplementation (p > 0.05). Our results indicate that the inclusion of DG as a partial corn-replacement supplementation for heifers under grazing represents a strategic tool not only related to meat quality, but also as an alternative to reduce food–feed competition.

Population genetic analyses reveal host association and genetically distinct populations of social parasite Solenopsis daguerrei (Hymenoptera: Formicidae) Dekovich, Allyson; Ryan, Sean; Bouwma, Andrew; Calcaterra, Luis Alberto; Silvestre, Rogerio; Staton, Margaret; Shoemaker, DeWayne Inquiline ant social parasites exploit other ant species for their reproductive benefit because they do not possess a worker caste. Due to their relative rarity in nature, the biology and natural history of inquilines are largely unknown. Likewise, not much research exists that details the close relationship between inquilines and their host(s), and how each organism influences the genetic structure of the other. Here, we conducted a comparative population genetics study to assess patterns of genetic structure within and among populations of inquiline Solenopsis daguerrei and its known fire ant hosts, which includes invasive Solenopsis invicta. Using nuclear and mitochondrial markers, we show that four genetically distinct groups of S. daguerrei likely exist, each with different degrees of host association. Consistent with previous inferences of the inquiline lifestyle, we find that inbreeding is common in S. daguerrei, presumably a result of intranidal mating and restricted dispersal. Results from this study, specifically host association patterns, may inform future biological control strategies to mitigate invasive S. invicta populations.

Uso de fototerapia LED para el tratamiento de heridas: amputación en ciervo Axis hembra Vieta, Cecilia; Rivulgo, Virginia Margarita; Sanchez Bruni, Sergio Fabian; Dángelo, Cristian; Lester, Marcelo Fabian; Rosatti, Juan José; Brusco, Jose; García, Jorge El uso de fuentes de luz de radiaciones no ionizantes como Light Emiting Diode (LED) para el tratamiento y el alivio del dolor e inflamación, se conoce como Fototerapia o Fotobiomodulación. La Fototerapia de LEDs de alta potencia instantánea, se genera por la estimulación del diodo semiconductor que produce una luz de muy baja potencia de emisión (1-5 mWatt). Los equipos de LEDs de alta potencia instantánea tienen mayor profundidad de penetración (véase fig. 1) que los LEDs comunes (acción más superficial). Las luces LED se utilizan con una longitud de onda que van desde los 380 a 436 nm (luz violeta), 436 a 495 nm (luz azul), 495 a 566 nm (luz verde), 566 a 589 nm (luz amarilla), 589 a 627 nm (luz naranja), 627 a 780 (luz roja), 770a 940 nm (luz infrarroja). Las mismas son responsables de diversas acciones sobre la célula, incluyendo su permeabilidad, su estimulación de mitocondrias, la síntesis de ATP y sobre proteínas como colágeno y elastina. (McGowan y Goff, 2016;Millis y Levine, 2014; Russel, 2005). A su vez, está documentado que además de acelerar el proceso de cicatrización de heridas, poseen efecto antimicrobiano, antiinflamatorio y analgésico, dependiendo de la longitud de onda utilizada (Tomazoni et al., 2017; Redondo y Sthepens, 2019). Desafortunadamente, al presente hay pocos estudios experimentales en especies superiores sobre los efectos favorables de fototerapia LED en el proceso de cicatrización de heridas (Dall-algon et al. 2009, Farouk et al. 2003, Meyer et al. 2010, Channal, et al., 2008; Deland et al., 2007).

Reducción de Sodio en Quesos Cremosos: Diseño del Proceso de Salado mediante Simulación Computacional Gill, Tomás Ramón; Lanteri, Mario Nicolas; Lespinard, Alejandro Rafael La alta ingesta de sal se asocia con un mayor riesgo de hipertensión arterial y enfermedades cardiovasculares. Los alimentos ricos en sodio, como los lácteos y embutidos, contribuyen significativamente a esta ingesta, lo que resalta la necesidad de reducir el contenido de sal durante su procesamiento. El objetivo de este estudio fue evaluar y diseñar el proceso de salado para quesos cremosos (con humedad del 53% p/p) con concentración estándar de sal (1,2 g/100 g de queso) y versiones reducidas en sodio (0,6 g/100 g de queso). Para lograr este objetivo, se desarrolló un modelo de simulación computacional 3D para predecir la difusión de NaCl en una horma de queso (dimensiones: 0,22 m x 0,22 m x 0,07 m) durante el proceso de salado a diferentes temperaturas (6, 12 y 18°C). El modelo de simulación se basó en la Segunda Ley de Fick y se resolvió numéricamente mediante el Método de Elementos Finitos, utilizando el software COMSOL Multiphysics. Los coeficientes de difusión empleados en el modelo se obtuvieron a partir de estudios previos y variaron según la temperatura, siendo de 3,14x10-10m²s-1 a 6°C, 5,47x10-10 m²s-1 a 12°C y 9,81x10-10 m²s-1 a 18°C. Las simulaciones permitieron predecir la distribución y contenidos medios de sal durante el salado a las diferentes condiciones. Con estos resultados, se determinaron los tiempos de salado necesarios para alcanzar una concentración de sal objetivo. Estos tiempos resultaron ser de 195, 100 y 60 minutos a 6, 12 y 18°C, respectivamente, para los quesos con concentración estándar de sal, mientras que, para los quesos reducidos en sodio, los tiempos fueron de 45, 25 y 15 minutos, respectivamente. El modelo desarrollado demostró ser efectivo para calcular los tiempos de salado a diferentes temperaturas. Además, se observó una reducción significativa del tiempo de salado al aumentar la temperatura y al reducir la concentración de NaCl en un 50%. Los resultados de este estudio serán de gran utilidad para optimizar la producción de quesos cremosos de manera más eficiente y saludable, contribuyendo así a la reducción del riesgo de enfermedades cardiovasculares asociadas con el alto consumo de sodio.