Decrease in the occurrence of the South American fur seal (Arctocephalus australis) in San Matías Gulf after a sudden episode of reoccupation; Disminución en la ocurrencia del lobo marino sudamericano Arctocephalus australis en el Golfo San Matías después de un episodio repentino de reocupación Bartés, Saia Nahir; Svendsen, Guillermo Martin; Romero, Maria Alejandra; González, Raúl Alberto The colonies of South American fur seals,Arctocephalus australis (SAFS), are currently experiencing population recovery, and as a consequence many coastal areas have been reoccupied. These areas are often haul-out sites used by SAFS for resting during the post-reproductive (winterly) season, andmay be playing a key role in the population recovery process since they seem to be located close to winter feeding areas that are far from the breeding colonies. This study reports on the trend in abundance of SAFS in a recently reoccupied winter area, the San Matías Gulf (SMG). The trend was evaluated with generalized linear models between 2007 and 2017 in two sectors of the SMG, Islote Lobos, the only rookery of this species in the area, and the northwest marine area of the gulf. Both sectors showed a negative trend. For Islote Lobos, the best selected models estimated a mean annual rate between -12.2% and -17.6%, and for the northwest area, between -19.02% and -29.9%. The population context suggests that most SAFS observed in 2007 may have been selecting other habitats over the following years; however, simultaneous censuses throughout their distribution range are needed in order to understand the redistribution and recolonization processes.; Las colonias del lobo marinode dos pelos sudamericano, Arctocephalus australis(SAFS), están experimentando una recuperación poblacional y como consecuencia muchas áreas costeras han sido reocupadas nuevamente. Muchas de estas áreas son apostaderos utilizados por los SAFS para descansar durante la temporada post-reproductiva (invernal). Las mismas pueden estar jugando un papel clave en el proceso de recuperación ya que estarían ubicadas cerca de áreas de alimentación invernales que se encuentran distantes de las colonias reproductivas. El presente estudio reporta la tendencia en la abundancia de SAFS en un área invernal recientemente ocupada, el Golfo San Matías (GSM). La tendencia se evaluó con modelos lineales generalizados entre los años 2007 y 2017 para dos sectores del golfo: el Islote Lobos, el único apostadero de esta especie, y el área marina del noroeste del golfo. Ambos sectores mostraron una tendencia negativa. Para el Islote Lobos, los modelosseleccionados estimaron una tasa promedio anual entre -12.2% y -17.6%, y para el área marina noroesteentre -19.02% y -29.9%. El contexto a nivel poblacional sugiere que la mayoría de los SAFS observados en 2007 pueden haber seleccionado otros hábitats durante los siguientes años. Sin embargo, para comprender los procesos de redistribución y recolonización se necesitan censos simultáneos en todo su rango de distribución.

Silencios y pandemia Lavagnino, Nicolas Jose; Lamberti, Matias; Grupo de Filosofía de la Biología ¿Qué dice un silencio? En la canción Necesito de Sui Generis, la flauta y el piano de las primeras estrofas dan lugar a la voz de un Nito Mestre que hasta el undécimo compás permanece en silencio, aunque no ausente. Un Charly García ansioso y aga- zapado aguarda su momento para ingresar en el compás diecinueve. En el tiempo que dura la canción, voces como las de Nito y Charly cantan y callan, alternándose con la de otros instrumentos. En la partitura se indican unos y otros; sonidos y silencios como cara y contracara de la expresión artística. Lo interesante de la obra musical es que ninguna voz o instrumento desaparece de la partitura al silenciarse, sino que simplemente permanece en potencia a la espera de otros compases. La presencia incontestable de los silencios en la música los convierte en elementos ineludibles a la hora de explicar, comprender y ejecutar la totalidad de cualquier pieza musical. Resulta que, sin embargo, por fuera de la música, los silencios pueden no ser una contribución positiva a la comprensión de un todo complejo. Sobre esto y a propósito de los tiempos extraños de pandemia que nos tocan vivir trata el presente texto colectivo. Como ya deja entrever esta breve introducción, el trabajo surge de la convicción de que la reflexión acerca de la actual crisis y su administración al igual que la ejecución de una pieza musical? depende también de los silencios involucrados.

Invasive ascidians: How predators reduce their dominance in artificial structures in cold temperate areas Giachetti, Clara Belen; Battini, Nicolás; Castro, Karen Lidia; Schwindt, Evangelina Artificial structures can provide suitable space for invasive species through a colonisable surface and refuge against predators. Besides several physical factors, invasive species can present different colonization success and dominance on structures that are connected to the sea floor (i.e. fixed) compared to structures that are suspended, depending on the differential predation pressure that affect both structures. Benthic and nektonic predators can reach fouling communities on fixed structures, while only nektonic predators can affect communities growing on suspended structures, depending on the distance to the sea floor. Only few studies tested both communities of predators at the same time in different artificial structures. In this study, we evaluated the effect of benthic and nektonic predators on the cover, composition and diversity on fouling communities and on the dominance of invasive ascidians on these communities, in two different types of artificial structures. We performed an experiment in the port area of Puerto Madryn (Southwestern Atlantic, Argentina) to compare the fouling community development between fixed and suspended structures and among different predator exclusion treatments. Results showed that benthic predators exerted a higher predation pressure than nektonic predators on the cover, composition and diversity of the fouling communities. In the absence of benthic predators, and even where nektonic predators were not excluded, communities were greatly dominated by two invasive ascidians, Ascidiella aspersa (Müller, 1776) and Ciona robusta Hoshino and Tokioka, 1967. Our results suggest that in this type of cold temperate ports, fouling organisms find refuge from benthic predators growing on suspended structures, where nektonic predators exert low predation pressure. We propose that, since benthic predators in temperate latitudes have an essential role decreasing invasive ascidians dominance and the cover of fouling communities, future studies should consider both predator communities, i.e. nektonic and benthic, in experimental designs performed to test biotic resistance and predation pressure.

Measurements and modeling of snow albedo at Alerce Glacier, Argentina: effects of volcanic ash, snow grain size and cloudiness Gelman Constantin, Julián; Ruiz, Lucas Ernesto; Villarosa, Gustavo; Outes, Ana Valeria; Bajano, Facundo N.; He, Cenlin; Bajano, Héctor; Dawidowski, Laura Elena The relevance of light absorbing impurities in snow albedo (and its effects in seasonal snow or glacier mass balance) have been under study for several decades. However, the effect of volcanic ash has been much less studied, and most articles studied only the effect of thick layers after direct deposition. There is also a knowledge gap in field measurements of seasonal snow and glaciers of the southern Andes, that only recently has started to be filled.We present here the first field measurements on Argentinian Andes, combined with albedo and mass balance modeling activities.Measured impurities content (1.1mgkg−1 to 30000 mgkg−1) varied abruptly in snow pits and snow/firn cores, due to high surface enrichment during ablation season and possibly local/regional wind driven resuspension and redeposition of dust and volcanic ash. In addition, we observed a high spatial hetereogeneity, due to seasonality, glacier topography and prevailing wind direction. Microscopical characterization showed that the major component was ash from recent Calbuco (2015) and Cordón Caulle (2011) volcanic eruption, with 10 minor presence of mineral dust and Black Carbon. We also found a wide range of measured snow albedo (0.26 to 0.81), whichreflected mainly the impurities content and the snow/firn grain size (due to aging). SNICAR model has been updated to model snow albedo taking into account the effect of cloudiness on incident radiation spectra, improving the match of modeled and measured values. We also ran sensitivity studies on the main measured parameters (impurities content and composition, snow grain size, layer thickness, etc) to assess which field measurements precision can improve the uncertainty of albedo modeling. Finally, we studied the impact of these albedo reductions in Alerce glacier using a spatially distributed surface mass-balance model. We found a large impact of albedo changes in glacier mass balance, and we estimated that the effect of observed ash concentrations can be as high as a 1.25mwe decrease in the glacier-wide annual mass balance (due to a 34 % of increase inthe melt during the ablation season).

Transformaciones en los modos de habitar Tilcara (Jujuy, Argentina): reflexiones antropológicas desde la pandemia; Transformations in the ways of dwelling in tilcara (Jujuy, Argentina): Anthropological reflections from the pandemic Carreras, Jesica Tamara; Petit de Murat, Facundo En este trabajo nos proponemos dar cuenta de algunas transformaciones ocurridas en la dinámica y la fisonomía de Tilcara (Jujuy, Argentina) durante la pandemia del COVID-19 y el aislamiento. En el texto, dialogamos con otros y otras habitantes del pueblo, a quienes hemos entrevistado para esta ocasión. Nos concentramos, así, en dejar un registro etnográfico sobre los cambios en los modos de habitar Tilcara en cuanto a ciertas problemáticas que se han evidenciado en este contexto, relacionadas con la movilidad, la economía, las prácticas culturales y el sector sanitario. Con este horizonte, presentamos, en primer lugar, algunas características de la Tilcara pre-pandémica, luego ofrecemos un contexto general de la provincia, para finalmente analizar las transformaciones producidas en Tilcara durante la pandemia.; In this article we present some of the transformations in the dynamics and physonomy of Tilcara (Jujuy, Argentina) during the COVID-19 pandemic and the lockdown. Throughout the text, we dialogue with other inhabitants of the town, whom we interviewed for the occasion. We focus on ethnographically recording the changes in the ways of dwelling in Tilcara in relation to certain problems that arose in this context, regarding mobility, economy, cultural practices and the health sector. With this outlook, in the text we present, firstly, some of the characteristics of pre-pandemic Tilcara, then we offer a general contextualization of the province, and finally we analyze the transformations produced in Tilcara during the pandemic.

A combined approach of MALDI-TOF mass spectrometry and multivariate analysis as a potential tool for the detection of SARS-CoV-2 virus in nasopharyngeal swabs Rocca, María Florencia; Zintgraff, Jonathan Cristian; Dattero, María Elena; Santos, Leonardo Silva; Ledesma, Martin Manuel; Vay, Carlos Alberto; Prieto, Mónica Raquel; Benedetti, Estefanía; Avaro, Martín; Russo, Mara Laura; Nachtigall, Fabiane Manke; Baumeister, Elsa Coronavirus disease 2019, known as COVID-19, is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The early, sensitive and specific detection of SARS-CoV-2 virus is widely recognized as the critical point in responding to the ongoing outbreak. Currently, the diagnosis is based on molecular real time RT-PCR techniques, although their implementation is being threatened due to the extraordinary demand for supplies worldwide. That is why the development of alternative and / or complementary tests becomes so relevant. Here, we exploit the potential of mass spectrometry technology combined with machine learning algorithms, for the detection of COVID-19 positive and negative protein profiles directly from nasopharyngeal swabs samples. According to the preliminary results obtained, accuracy =67.66 %, sensitivity =61.76 %, specificity =71.72 %, and although these parameters still need to be improved to be used as a screening technique, mass spectrometry- based methods coupled with multivariate analysis showed that it is an interesting tool that deserves to be explored as a complementary diagnostic approach due to the low cost and fast performance. However, further steps, such as the analysis of a large number of samples, should be taken in consideration to determine the applicability of the method developed.

Immediate and transgenerational effects of thymol supplementation, inactivated Salmonella and chronic heat stress on representative immune variables of Japanese quail Videla, Emiliano Ariel; Giayetto, Octavio; Fernández, María Emilia; Chacana, Pablo Anibal; Marin, Raul Hector; Nazar, Franco Nicolas Environmental challenges are integrated in the inmunoneuroendocrine interplay, impacting the immune system of the challenged individuals, and potentially implying transgenerational effects on their offspring. This study addressed whether dietary supplementation with thymol can modulate the immune response of adult Japanese quail when simultaneously exposed to an inoculum of inactivated Salmonella Enteritidis and a chronic heat stress (CHS). We also evaluated whether the experienced situations by adults can affect the immune response of their undisturbed offspring. In the parental generation, supplemented quail exposed to CHS had a higher inflammatory response and similar values of the heterophil/lymphocyte (H/L) ratio than those that were not supplemented. In their offspring, those chicks whose parents were exposed to CHS showed higher inflammatory response and lower antibody production. Regarding the H/L ratio, chicks whose parents were supplemented showed lower H/L ratio values. Dietary supplementation with thymol partially and positively modulated the inflammatory response and avoided H/L ratio alteration in the parental generation exposed to high environmental temperatures, suggesting these adults were better at dealing with the challenge. The lower H/L ratio values in the offspring suggests that chicks are more capable to deal with potential stressful situations associated with conventional breeding conditions.

Meteorological variables associated with the temporal oviposition rate of Aedes aegypti (Diptera: Culicidae) in Resistencia city, Chaco province, Northeastern Argentina Gimenez, Javier Orlando; Alvarez, Carla Noel; Almiron, Walter Ricardo; Stein, Marina Aedes aegypti is the main vector of dengue virus in South America. In the last fifteen years, Argentina has suffered three large dengue outbreaks: one in 2009, another one in 2016 and the current 2020 outbreak, with 26,000, 66,000 and more than 43,000 confirmed cases, respectively. These outbreaks are associated with the circulation of the virus in neighboring countries due to the constant movement of people across the frontier. In 2009, the main province affected was Chaco province, with 11,037 confirmed cases (50% of total cases). Thus, the aim of this study was to characterize the temporal oviposition rate of Aedes aegypti in Resistencia, the capital city of this province, in relation to meteorological variables. Mosquitoes were sampled weekly, from April 2015 to March 2017, using ovitraps located in houses randomly selected within the urban area. Oviposition rate was evaluated by means of the total number of eggs collected per week and the proportion of positive ovitraps per week. The coefficient of variation for these two indicators was estimated for the whole study period and then compared using the Wilcoxon Pair test. A generalized linear model (GLM) was performed to infer association between meteorological variables and oviposition rate without time lag and with a time lag of 1 to 4 weeks, considering the biology of this mosquito species. Comparisons between the coefficient of variation of egg number versus the proportion of positive ovitraps showed significant differences, being the former more variable than the latter. The most significant time lag was 2 weeks for the minimum temperature. The number of Ae. aegypti eggs increased 4.05 times when the minimum temperature increased 1°C two weeks before, and decreased 0.69 times with an increase of 1 unit in relative humidity. No eggs were collected when the temperature was below 8°C. The oviposition rate was associated with the increase in the critical minimum temperature (over 8°C) and the weekly frequency of precipitation and dissociated with relative humidity. The maximum oviposition rate was recorded between November and January of both years. The GLM could not explain the relation between meteorological variables and the proportion of positive ovitraps. The peaks of Ae. aegypti egg abundance occurred simultaneously with dengue autochthonous cases recorded in Chaco province, resulting in a good indicative of the period of greatest epidemiological risk.

Gastropods as intermediate hosts of angiostrongylus spp: In the americas. Bioecological characteristics and geographical distribution Valente, Romina; Robles, Maria del Rosario; Diaz, Julia Inés BACKGROUND Intermediate hosts are key organisms in maintaining parasite life cycles, because they can act as amplifiers in the transmission from natural reservoirs to humans. One of the most important groups of intermediate hosts for zoonotic nematode infections are gastropods,slugs and snails. These are essential organisms in the larval development of Angiostrongylus species. OBJECTIVES The objective of this paper is to review reports of Angiostrongylus spp. in naturally infected gastropods from the Americas, taking into account the diagnostic methods used in their identification, to be able to provide more accurate list of their intermediate hosts. We also discuss the factors that aid the dispersion of Angiostrongylus spp. in the Americas. METHODS This study reviews scientific publications and book sections on Angiostrongylus spp. in the Americas, including original works assessing larvae of Angiostrongylus in intermediate hosts. The eligible reports were classified accordingly to their geographical location, year of first record, and the larvae identification methodologies used. Digital repositories were used for the search. The bioecological characteristics of the main intermediate hosts are summarised. FINDINGS A total of 29 gastropod species that are naturally infected with Angiostrongylus spp. have been reported as intermediate hosts, 16 of which are land snails, two are freshwater snails, and 11 land slugs. MAIN CONCLUSIONS This study highlights the importance of integrative studies, analysing both the etiological agent and its transmission dynamic in the environment, the biological and ecological characteristics of the hosts, and the impact on host populations. It is necessary to increase interdisciplinary studies to determine the potential epidemiological health risk of angiostrongyliasis in the Americas, and thus be able to establish prevention, monitoring and contingency strategies in the region.

Diurnal variation of heart rate variability as a physiological index of mood and emotion regulation processes in Major Depression and Borderline Personality Disorder Wainsztein, Agustina Edith; Abulafia, Carolina Andrea; Goldberg, Ximena; Camacho Téllez, Vicente; Vulcano, Mercedes; Vigo, Daniel Eduardo; Menchón, José M.; Soriano Mas, Carles; Nemeroff, Charles B.; Guinjoan, Salvador Martín; Castro, Mariana Nair Background: Heart rate variability (HRV), a measure of autonomic nervous system activity, has been studied in a number of psychiatric disorders during the resting state but evidence on its circadian patterns in Major Depressive Disorder (MDD) and Borderline Personality Disorder (BPD) is scarce. We sought to identify and differentiate HRV circadian patterns in MDD, BPD and healthy controls (HC) while exploring potential physiological mechanisms associated with mood and emotion dysregulation. Methods: 24-Hour electrocardiographic recordings were obtained from fifty subjects (16 HC, 18 BPD, 16 MDD). HRV was calculated during sleep and wake periods. Associations with mood and affect measures, and with cognitive emotion regulation strategies and self-reported difficulties in emotion regulation (DERS) were examined. Participant’s resilience traits were explored in relation to mood and emotion regulation variables. Results: Lower diurnal measures of HRV (i.e, RMSSD and HF) were observed in MDD subjects compared to HCs. Decreased HF was observed during wake vs. sleep in MDD patients. HAM-D and negative affect scores negatively correlated with HRV in MDD and BPD respectively. MDD and BPD exhibited a positive relationship between the implementation of emotion regulation strategies and HRV compared to HC. Increased resilience was associated with lower HAM-D and DERS scores in BPD and HC. Conclusion: HRV alterations characterized by low diurnal cardiac parasympathetic control constitute a potential trait biomarker of major depression and psychiatric vulnerability to depressive episodes in BPD. HRV anomalies in MDD may persist during clinical remission. Diurnal HRV may represent a psychophysiological index of mood and emotion regulation

Otro estilo científico y tecnológico es posible; Another scientific and technological style is possible; Outro estilo científico e tecnológico é possível Red de Pensamiento Latinoamericano en Ciencia, Tecnología y Sociedad; Gonzalez-Jose, Rolando En junio de 2020 fue creada la Red de Pensamiento Latinoamericano en Ciencia, Tecnología y Sociedad (Red PLACTS). Conformada por integrantes del sector científico, tecnológico y universitario, impulsa una agenda que ponga el conocimiento, los recursos y el complejo CyT en proyectos destinados a resolver necesidades y problemas de nuestra sociedad. Se propone participar e incidir en las decisiones que se toman en la gestión de los organismos de CyT, contribuyendo con propuestas e ideas que apor-ten a construir un proyecto de país popular, igualitario, democrático, soberano, solidario, con perspectiva feminista y desde una mirada federal. Rescata y recupera en proyectos y acciones concretas los aportes de lo que fue históricamente el PLACTED (Pensamiento Latinoamericano en Ciencia, Tecnología, Desarrollo y Dependencia). En este primer docu-mento se describen las características principales de la dinámica tecnocientífica domi-nante a nivel global y se presentan algunas propuestas para impulsar un estilo científico tecnológico propio en nuestro país y la región.; In June 2020, the Latin American Thought Network in Science, Technology and Society (PLACTS Network) was created. Made up of members of the scientific, technological and university sectors, it promotes an agenda that puts knowledge, resources and the S&T complex in projects aimed at solving the needs and problems of our society. It is proposed to participate and influence the decisions made in the management of S&T organizations, contributing with proposals and ideas that contribute to building a project of a popular, egalitarian, democratic, sovereign, supportive country, with a feminist perspective and from a perspective federal. It rescues and recovers in projects and concrete actions the contributions of what was historically PLACTED (Latin American Thought in Science, Technology, Development and Dependency). This first document describes the main characteristics of the dominant techno-scientific dynamics at a global level and presents some proposals to promote a technological scientific style of its own in our country and the region; Em junho de 2020, foi criada a Rede Latino-americana do Pensamento em Ciência, Tecnologia e Sociedade (Rede PLACTS). Composto por membros dos setores científico, tecnológico e universitário, promove uma agenda que coloca o conhecimento, os recursos e o complexo da C&T em projetos que visam a resolução das necessidades e dos problemas da nossa sociedade. Propõe-se participar e influenciar as decisões tomadas na gestão das organizações de C&T, contribuindo com propostas e ideias que contribuam para a construção de um projeto de país popular, igualitário, democrático, soberano, solidário, com uma perspectiva feminista e sob uma perspectiva Federal. Resgata e resgata em projetos e ações concretas as contribuições do que foi historicamente PLACTED (Pensamento Latino-Americano em Ciência, Tecnologia, Desenvolvimento e Dependência). Neste primeiro documento são descritas as principais características da dinâmica técnico-científica dominante a nível global e apresentadas algumas propostas para promover um estilo científico tecnológico próprio no nosso país e na região.

Las transformaciones de un fandomen tiempos de aislamiento: El caso del Círculo de Lectores de Harry Potter Argentina; Fandom Transformation in Times of Isolation: The Case of Harry Potter Reading Club in Argentina Aller, Roberta; Cuestas, Paula En el artículo se muestran las transformaciones que atravesó un club de fans de Harry Potter, a partir de las medidas de aislamiento social dispuestas frente al avance del COVID-19. Se describen los orígenes del club, ligados a un momento de expansión de las tecnologías digitales y los encuentros "cara-a-cara" habitualmente organizados por el club. Como objetivo central, mediante una metodología de etnografía digital se analizan las nuevas dinámicas que lleva adelante el CHP en un contexto de obligada "virtualidad"; The article shows the transformations that a Harry Potter fan`s club went through as a result of the social isolation measures set out in the face of COVID-19’s spread. The origins of the club are described, bound to a time characterized by the expansion of digital technologies and the "face-to-face" gatherings habitually organized by the club. As a central objective, by a digital ethnography methodology, the new dynamics carried out by the CHP are analyzed in a context of mandatory "virtuality".

Trace element composition of amphibole and petrogenesis of hornblendites and plutonic suites of Cretaceous magmatic arcs developed in the Fuegian Andes, southernmost South America Torres García, M.F.; Calderón, M.; Ramírez de Arellano, C.; Hervé, Francisco; Opitz, J.; Theye, T.; Fanning, Christopher Mark; Pankhurst, Robert; Gonzalez Guillot, Mauricio Alberto; Fuentes, F.; Babinski, M. The evolution of continental crust in convergent margins can be explored in southernmost South America (54-56°S). Plutonic rocks of the Fuegian Batholith and the rear-arc satellite Ushuaia Pluton were emplaced within the magmatic arc and the Fuegian fold-and-thrust belt, respectively. They record subduction zone processes in two distinct tectonic settings during the evolution of the Rocas Verdes Basin. We report new U-Pb zircon geochronology, bulk rock chemistry, Sr-Nd isotope data, and EPMA and in-situ LA-ICP-MS analyses of amphibole from ‘hornblendites’ and gabbroic-granitoid suites in order to evaluate the origin and evolution of the magmatic plumbing systems in the upper plate of the subduction zone. Textural relationships and amphibole compositions in hornblendite indicate crystallization at lower crustal depths with pressures of 7-8 kbar in the Fuegian Batholith and of 5-6 kbar in the Ushuaia Pluton. Lower Cretaceous suites of hornblendite and calc-alkaline hornblende-gabbro, diorite and tonalite in the Fuegian Batholith have εNdt values ranging between +2 and +4. They were emplaced within an island arc coeval with mid-oceanic type spreading in the Rocas Verdes back-arc basin. Isotope ratios and amphibole compositions in hornblendite indicate crystallization from primitive and hydrous sub-alkaline basaltic melts with relatively low LREE/HREE and low alkali contents. The Late Cretaceous plutons in the fold-and-thrust belt were emplaced after the tectonic juxtaposition of Rocas Verdes ophiolitic complexes. The Ushuaia Pluton, consisting of clinopyroxene-hornblende cumulates, hornblende-gabbro, diorite and monzodiorite, was emplaced during the waning stage of Late Cretaceous magmatism. In this case hornblendite amphiboles show high contents of alkalis, LREE and incompatible elements with a strong crustal affinity (Th, Ba, Rb). The enriched incompatible trace element patterns indicate their derivation from K-rich transitional magmas formed in supra-subduction settings. Chemical variations in amphibole from hornblendites and spatially related plutonic rocks are evaluated in terms of fluid flux from the subducted slab and partial melting of the sub-arc mantle, ultimately controlled by the thermal state of the subducted slab and convergence rates.

Nanosystems Applied to HIV Infection: Prevention and Treatments Macchione, Micaela Alejandra; Aristizabal, Dariana; Figueroa, Francisco Nicolas; Muñoz Fernández, María Ángeles; Strumia, Miriam Cristina Sexually-transmitted infections (STIs) are a global health concern worldwide as they cause acute diseases, infertility, and significant mortality. Among the bacterial, viral, and parasitic pathogens that can be sexually transmitted, human immunodeficiency virus (HIV) has caused one of the most important pandemic diseases, which is acquired immune deficiency syndrome (AIDS). 32.7 million people have died from AIDS-related illnesses since the start of the epidemic. Moreover, in 2019, 38 million people were living with HIV worldwide. The need to deal with this viral infection becomes more obvious, because it represents not only a problem for public health, but also a substantial economic problem. In this context, it is necessary to focus efforts on developing methods for prevention, detection and treatment of HIV infections that significantly reduce the number of newly infected people and provide a better quality of life for patients. For several decades, biomedical research has been developed allowing quick solutions through the contribution of effective tools. One of them is the use of polymers as vehicles, drug carrier agents, or as macromolecular prodrugs. Moreover, nanosystems (NSs) play an especially important role in the diagnosis, prevention, and therapy against HIV infection. The purpose of this work is to review recent research into diverse NSs as potential candidates for prevention and treatment of HIV infection. Firstly, this review highlights the advantages of using nanosized structures for these medical applications. Furthermore, we provide an overview of different types of NSs used for preventing or combating HIV infection. Then, we briefly evaluate the most recent developments associated with prevention and treatment alternatives. Additionally, the implications of using different NSs are also addressed.

Seasonality dictates changes in the ecological interactions among spatial dominants Gastaldi, Marianela; Firstater, Fausto Nahuel; Romero, María Alejandra; Pereyra, Patricio Javier; Narvarte, Maite Andrea Marine coasts are dynamic environments where spatial-physical gradients interact with seasonality. In the Patagonia in particular, high temperatures and strong winds lead to stressing physical conditions that shape intertidal communities. In a previous study, we found that the interaction between the sponge Hymeniacidon perlevis and the macroalga Ulva lactuca was context-dependent, switching from positive at the harsher intertidal to negative at the milder subtidal environment. Temporal variation in the physical variables, however, may also affect species performance and interaction strength. Since Patagonian shores are strongly seasonal environments, we evaluated how the interactions (competitive or cooperative) among these twospatially dominant species changed over a temporal-stress gradient throughout a year. We predicted that the macroalga would facilitate the sponge in seasons with more severe environmental conditions, whereas negative or neutral interactions would prevail when environmental conditions were milder. Our results demonstrated that the sign and intensity of the interaction between Hymeniacidon and Ulva changed over the seasons and coincided with a hump-shaped model, involving a neutral interaction in the milder seasons of autumn and winter, then switching to a positive one in the inclement springtime, and finally shifting to a negative relationship in the harshness of the summer. The amelioration of stressful conditions through shading did not satisfactorily explain the underlying mechanism for this varying interaction, an aspect that still remains unclear. Nevertheless, several mechanisms are discussed both within the context of the stress gradient hypothesis and the specific physiological constraints of intertidal organisms.

La percepción del tiempo: un abordaje psicofisiológico; A percepção do tempo: uma abordagem psicofisiológica; La perception du temps: une approche psychophysiologique; Time perception: a psychophysiological approach Squillace, Mario Rodolfo; Picón Janeiro, Jimena Cristina; Menéndez, Javier; Azzollini, Susana Celeste La cronobiología ha establecido la presencia de relojes internos en los organismos que miden diferentes frecuencias o ritmos. Este artículo aborda en una revisión cómo son esos relojes en el caso de la percepción subjetiva del paso del tiempo. A partir del modelo temprano de un marcapasos general para la estimación del tiempo hoy se concibe la presencia de modelos intrínsecos con mecanismos y áreas cerebrales diferenciadas. Si la estimación del tiempo requiere procesos controlados u automáticos será procesada por sistemas distintos; así como las tareas que implican procesamiento temporal de origen sensorial o motor. Poblaciones de neuronas procesan diferentes tareas de estimación temporal. Los mecanismos de rampa y de relojes poblacionales son propuestas teóricas de lo que ocurre a nivel sináptico y de redes neurales. Finalmente, se discuten factores que afectan la estimación subjetiva de la percepción del tiempo. Se ha mostrado que la edad, la motivación, la atención y el estado emocional afectan la velocidad con que se percibe el tiempo. La motivación intrínseca, la atención centrada en la tarea y el estado de baja activación emocional provocan enlentecimiento de la percepción del tiempo lo que lleva a su subestimación. Por otra parte, la motivación extrínseca, la atención focalizada en el paso del tiempo y la alta activación emocional provocan el efecto contrario, la percepción acelerada del tiempo, lo que provoca su sobreestimación.; A cronobiologia estabeleceu a presença de relógios internos nos organismos que medem diferentes frequências ou ritmos. Esse artigo aborda em uma revisão como esses relógios são no caso da percepção subjetiva da passagem do tempo. Partindo do modelo inicial de um marcapasso geral para estimativa de tempo, atualmente, se concebe a presença de modelos intrínsecos com áreas e mecanismos cerebrais diferenciados. Hipotetiza-se que se a estimativa de tempo requer processos controlados, ou automáticos, ela poderá ser processada por diferentes sistemas; bem como tarefas que envolvem processamento temporal de origem sensorial ou motora. Populações de neurônios processam diferentes tarefas de estimativa temporal. Os mecanismos de rampa e os relógios populacionais são propostas teóricas do que acontece no nível da rede sináptica e neural. Finalmente, os fatores que afetam a estimativa subjetiva da percepção do tempo, ainda, são discutidos. Encontrou-se que a idade, a motivação, a atenção e o estado emocional afetam a velocidade com que o tempo é percebido. A motivação intrínseca, a atenção voltada para a tarefa e o estado de baixa ativação emocional causam um abrandamento na percepção do tempo, levando à sua subestimação. Por outro lado, a motivação extrínseca, a atenção voltada para a passagem do tempo e a alta ativação emocional causam o efeito oposto a percepção acelerada do tempo que causa sua superestimação.; La chronobiologie a établi la présence d'horloges internes dans des organismes qui mesurent différentes fréquences ou rythmes. Cet article aborde dans une revue comment ces horloges sont dans le cas de la perception subjective du passage du temps. À partir du modèle précoce d'un stimulateur cardiaque général pour l'estimation du temps, on conçoit aujourd'hui la présence de modèles intrinsèques avec des zones et des mécanismes cérébraux différenciés. Si l'estimation de temps nécessite des processus contrôlés ou automatiques, elle sera traitée par différents systèmes; ainsi que les tâches qui impliquent un traitement temporel d'origine sensorielle ou motrice. Les populations de neurones traitent différentes tâches d'estimation temporelle. Les mécanismes de rampe et les horloges de population sont des propositions théoriques de ce qui se passe au niveau des réseaux synaptiques et neuronaux. Enfin, les facteurs qui affectent l'estimation subjective de la perception du temps sont discutés. Il a été démontré que l'âge, la motivation, l'attention et l'état émotionnel affectent la vitesse à laquelle le temps est perçu. La motivation intrinsèque, l'attention focalisée sur la tâche et l'état de faible activation émotionnelle provoquent un ralentissement de la perception du temps, ce qui conduit à sa sous-estimation. En revanche, la motivation extrinsèque, l'attention focalisée sur le passage du temps et la forte activation émotionnelle provoquent l'effet inverse, la perception accélérée du temps, qui provoque sa surestimation.; Chronobiology has established the presence of internal clocks in the organisms that measure at different frequencies or rhythms. This article addresses in a review how these clocks are in the case of the subjective perception of the passage of time. Today, the presence of intrinsic models with different brain areas and mechanisms is conceived from the early model of a general pacemaker for time estimation. If the time estimate requires controlled or automatic processes, it will be processed by different systems. As well as, tasks that involve temporal processing of sensory or motor origin. Neuron populations process different temporal estimation tasks. The ramp mechanisms and population clocks are theoretical proposals of what happens at the synaptic and neural network level. Finally, factors that affect the subjective estimation of time perception are discussed. Age, motivation, attention, and emotional state have been shown to affect the speed with which time is perceived. Intrinsic motivation, attention focused on the task and the state of low emotional activation cause the slowing of the perception of time, leading to its underestimation. On the other hand, extrinsic motivation, attention focused on the passage of time and high emotional activation cause the opposite effect, accelerated perception of time, leading to its overestimation.

Objetos durables, mundos inestables: Modos de hacer y prácticas referenciales en las sociedades precoloniales de la región de Soto, Córdoba, Argentina.; Durable objects, unstable worlds: Ways of doing and referential practices in pre-colonial societies of the Soto region, Córdoba, Argentina Laguens, Andres Gustavo Se intenta una aproximación a los modos del habitar y la producción y reproducción de los mundos locales de las sociedades precoloniales de la localidad de Villa de Soto, Córdoba, Argentina. Se reflexiona cómo distintas materialidades y formas de hacer se entrelazan en un juego de referencias mutuas, que ponen en realce ciertos modos locales de entender y estar en el mundo. Encontramos una relación estrecha entre las formas de hacer cerámica en base a cestas y redes y otras materialidades tales como las de otros estilos cerámicos, las marcas corporales como se manifiestan en estatuillas de cerámica, algunos objetos líticos y el tratamiento de los cuerpos humanos, que permite postular la existencia local de ciertos principios relacionales en las interacciones entre las personas, las cosas y el mundo, que giran en torno a la noción de inestabilidad crónica y la vigencia de prácticas socio-materiales que apuntan a su opuesto, la perduración, congruente con cosmologías nativas sudamericanas, como el perspectivismo.; An approach is attempted to the ways of living and the production and reproduction of the local worlds of the pre-Hispanic agro-pottery societies of the town of Villa de Soto, Córdoba, Argentina. It reflects on how different materialities and ways of doing are intertwined in a game of mutual references, which highlight certain local ways of understanding and being in the world. We find a close relationship between the ways of making ceramics based on baskets and nets, and other materialities such as other ceramic styles, body marks as manifested in ceramic statuettes, some lithic objects and the treatment of human bodies, which allows us to postulate the local existence of certain relational principles in interactions between people, things and the world, which revolve around the notions of chronic instability and the validity of socio-material practices pointing to its opposite, permanence, congruent with native South American cosmologies, such as perspectivism.

On the strain-induced martensitic transformation process of the commercial AISI 304 stainless steel during cyclic loading Farias, Francisco David; Alvarez, Iris; Armas, Alberto Franklin Low-cycle fatigue tests were performed on metastable austenitic steel at two initial material states, the as-received, with a high crystal defect density, and the solution treated one, with fewer crystal defects. Cyclic curves have shown different hardening behavior depending on the initial material states. To understand these differences, the back and friction stresses were studied from the hysteresis loop analysis. The correlation of these results with the volume fraction of induced martensite and the observed microstructure revealed that the cyclic hardening behavior strongly depends on the existence of potential martensite nucleation sites.

Células madre/estromales mesenquimales: su potencial terapéutico en medicina; Mesenchymal stem/stromal cells: their therapeutic potential in medicine Domínguez, Luciana María; Fiore, Esteban Juan; Mazzolini Rizzo, Guillermo Daniel La terapia celular y la medicina regenerativa son áreas en gran desarrollo en la investigación biomédica. En la mayoría de los tejidos existen mecanismos de auto-reparación llevados a cabo, principalmente, por células madre o progenitoras residentes con capacidad para diferenciarse y reemplazar a las células dañadas o para secretar factores tróficos que induzcan el proceso regenerativo. Dado que estos mecanismos de reparación no siempre son suficientes, se postula que la terapia celular puede contribuir a la regeneración de los tejidos sometidos a injuria. Las células madre/estromales mesenquimales (MSCs, del inglés Mesenchymal Stem/Stromal Cells) son un tipo de progenitor adulto multipotente, que tienen la capacidad de expandirse in vitro con facilidad cuando son aisladas de su nicho in vivo, migrar selectivamente a los tejidos lesionados, modular y evadir el sistema inmunológico, y secretar factores tróficos que ayudan a la reparación tisular. Asimismo, la fácil manipulación ex vivo permitiría también usarlas como vehículos de genes terapéuticos. Las principales fuentes de obtención son la médula ósea, el tejido adiposo y cordón umbilical. Los numerosos estudios pre-clínicos y clínicos han demostrado que las MSCs parecieran ser seguras tanto para uso autólogo como alogénico. En este trabajo se resumen las propiedades de las MSCs y su potencial terapéutico para una amplia gama de enfermedades, también presentamos los distintos ensayos clínicos avanzados que las posicionan en el ámbito biomédico como una herramienta interesante para la regeneración de tejidos y el tratamiento de enfermedades inflamatorias.; Cell therapy and regenerative medicine are currently active areas for biomedical research. In most tissues, there are self-repair mechanisms carried out mainly by resident stem cells that can differentiate and replace dead cells or secrete trophic factors that stimulate the regenerative process. These mechanisms often fail in degenerative diseases; thus it is postulated that exogenous cell therapy can contribute to tissue regeneration and repair. Mesenchymal stem cells (MSCs) are multipotent adult stem/progenitor cells, which could be easily expanded in vitro and have the ability to selectively migrate toward injured tissues, evade the immune system recognition, and secrete trophic factors to support tissue repair. Furthermore, MSCs could be engineered for the delivery of therapeutic genes. The main sources for MSCs are bone marrow, adipose tissue, and umbilical cord. A number of pre-clinical and clinical studies have shown that MSCs therapy is safe for both autologous and allogeneic uses. This review summarizes information about the properties of MSCs and their therapeutic potential for a broad spectrum of diseases. We also present here the last data about clinical trials that position the use of MSCs as an interesting tool for tissue regeneration and the treatment of inflammatory diseases.

Determinación de la eficacia de antihelmínticos para el tratamiento de la gastroenteritis verminosa en caprinos de la provincia de Tucumán; Determination of the efficacy of anthelmintics used in the control of gastrointestinal nematodes of goats from Tucumán, Argentina Chocobar, Marianna Laura Elis; Diambra, Priscila; Terán Alurralde, María del Rosario; Bustos, María José; Prado, María José; Gonzalez Moreno, Candelaria; Fernández, Jorge Luis; Salinas, Carmen; Solaligue, Paola Blanca del Valle; Rosa, Ramiro José En la Argentina, el 93% de la producción caprina en la Argentina es desarrollada por pequeños productores deagriculturas de subsistencia, quienes, por lo general, utilizan antihelmínticos sin asesoramiento profesional, lo que, probablemente, hallevado al desarrollo de resistencia, comprometiendo seriamente la sustentabilidad del control de nematodos. El objetivo de esteestudio es determinar la eficacia de la ivermectina, el albendazol y el levamisol para el tratamiento de la gastroenteritis verminosa encuatro grupos de ocho caprinos cada uno, mediante el Test de Reducción del Conteo de Huevos (TRCH). Los resultados demostraronun 100% de reducción del número de HPG para los grupos tratados con albendazol y levamisol y un 17% de reducción para el grupotratado con ivermectina, con respecto al grupo control, lo que permite inferir que existe resistencia a este fármaco.; Almost 93% of goat production in Argentina is developed by small farmers, who generally use anthelmintics without professional advice, which has led to the development of resistance, seriously compromising the sustainability of nematode control. This study aims to determine the efficacy of ivermectin, albendazole and levamisole for the treatment of verminous gastroenteritis in four groups of eight goats each, using the Faecal Egg Count Reduction Test (FECRT). The results showed a 100% reduction in the number of EPG for the groups treated with albendazole and levamisole and a 17% reduction for the group treated with ivermectin, compared to the control group, which allows us to infer that there is resistance to this drug.