Efectos compañero en contextos escolares altamente segregados; Peer effects in highly segregated school contexts Krüger, Natalia Soledad Los sistemas educativos latinoamericanos se posicionan entre los más segregados del mundo: los grupos de estudiantes provenientes de distinto contexto social se distribuyen de forma desigual entre sus escuelas, con escasa interacción entre sí. Empleando datos de PISA 2018, el trabajo evalúa la existencia de efectos compañero sobre el desarrollo de competencias en las áreas de Lectura, Matemática y Ciencia y sobre la expectativa ocupacional de los alumnos de 15 años de edad en la región. Para ello, se estiman modelos de regresión multinivel multivariados. Se constata la presencia de efectos significativos de la composición socioeconómica escolar sobre dichos resultados, lo cual permite afirmar que la situación de segregación tiende a reforzar la inequidad educativa y social. Esto es así porque los alumnos de origen social más desfavorecido suelen asistir a escuelas cuyo alumnado se encuentra en similares condiciones, potenciando su desventaja inicial. Lo contrario ocurre para aquellos de mayor nivel socioeconómico. La evidencia aportada se encuentra en línea con los antecedentes disponibles para América Latina, contribuyendo a visibilizar el fenómeno de la segregación social escolar como un problema central de sus sistemas educativos. Se insta a las autoridades y a toda la comunidad educativa a pensar y consensuar estrategias para mitigarlo.; Latin American education systems are among the most segregated in the world: since the distribution of students from different social backgrounds across schools is uneven, they scarcely interact with each other. Drawing on PISA 2018 data, this study evaluates the existence of peer effects on the development of Reading, Mathematics and Science competences and on the occupational expectation of 15-year-old students in the region. To this end, it presents the estimation of multivariate multilevel regression models. Results confirm the presence of school socioeconomic composition effects on these outcomes, which allows the conclusion that the situation of segregation tends to reinforce educational and social inequality. The reason is that students from a vulnerable background are likely to attend schools with a similar socioeconomic intake, strengthening their initial disadvantage. The opposite occurs for students from a more favorable social origin. Findings are in line with previous research in Latin America, highlighting the phenomenon of socioeconomic school segregation as a central problem in these education systems. School system authorities and the entire educational community are urged to develop and agree on strategies to mitigate it.

Immunobiotic Lactobacillus jensenii TL2937 Alleviates Dextran Sodium Sulfate-Induced Colitis by Differentially Modulating the Transcriptomic Response of Intestinal Epithelial Cells Sato, Nana; García Castillo, Valeria; Yuzawa, Mao; Islam, Md Aminul; Albarracín, Leonardo Miguel; Tomokiyo, Mikado; Ikeda Ohtsubo, Wakako; García Cancino, Apolinaria; Takahashi, Hideki; Villena, Julio Cesar; Kitazawa, Haruki Immunobiotics have emerged as a promising intervention to alleviate intestinal damage in inflammatory bowel disease (IBD). However, the beneficial properties of immunobiotics are strain dependent and, therefore, each strain has to be evaluated in order to demonstrate its potential application in IBD. Our previous in vitro and in vivo studies demonstrated that Lactobacillus jensenii TL2937 attenuates gut acute inflammatory response triggered by Toll-like receptor 4 activation. However, its effect on colitis has not been evaluated before. In this work, we studied whether the TL2937 strain was able to protect against the development of colitis in a dextran sodium sulfate (DSS)-induced mouse model and we delved into the mechanisms of action by evaluating the effect of the immunobiotic bacteria on the transcriptomic response of DSS-challenged intestinal epithelial cells. L. jensenii TL2937 was administered to adult BALB/c mice before the induction of colitis by the administration of DSS. Colitis and the associated inflammatory response were evaluated for 14 days. Mice fed with L. jensenii TL2937 had lower disease activity index and alterations of colon length when compared to control mice. Reduced myeloperoxidase activity, lower production of pro-inflammatory (TNF-α, IL-1, CXCL1, MCP-1, IL-15, and IL-17), and higher levels of immunoregulatory (IL-10 and IL-27) cytokines were found in the colon of TL2937-treated mice. In addition, the treatment of porcine intestinal epithelial (PIE) cells with L. jensenii TL2937 before the challenge with DSS differentially regulated the activation of the JNK pathway, leading to an increase in epithelial cell integrity and to a differential immunotranscriptomic response. TL2937-treated PIE cells had a significant reduction in the expression of inflammatory cytokines (TNF-α, IL-1α, IL-1β, IL-6, IL-15), chemokines (CCL2, CCL4, CCL8, CXCL4, CXCL5, CXCL9, CXCL10), adhesion molecules (SELE, SELL, EPCAM), and other immune factors (NCF1, NCF2, NOS2, SAA2) when compared to control cells after the challenge with DSS. The findings of this work indicate that (a) L. jensenii TL2937 is able to alleviate DSS-induced colitis suggesting a potential novel application for this immunobiotic strain, (b) the modulation of the transcriptomic response of intestinal epithelial cells would play a key role in the beneficial effects of the TL2937 strain on colitis, and (c) the in vitro PIE cell immunoassay system could be of value for the screening and selection of new immunobiotic strains for their application in IBD.

A decade of arbovirus emergence in the temperate southern cone of South America: dengue, Aedes aegypti and climate dynamics in Córdoba, Argentina Estallo, Elizabet Lilia; Sippy, Rachel; Stewart-Ibarra, Anna M.; Grech, Marta Gladys; Benitez, Elisabet Marina; Ludueña Almeida, Francisco; Ainete, Mariela; Frias Cespedes, María; Robert, Michael; Romero, Moory M.; Almiron, Walter Ricardo Background: Argentina is located at the southern temperate range of arboviral transmission by the mosquito Aedes aegypti and has experienced a rapid increase in disease transmission in recent years. Here we present findings from an entomological surveillance study that began in Córdoba, Argentina, following the emergence of dengue in 2009. Methods: From 2009 to 2017, larval surveys were conducted monthly, from November to May, in 600 randomly selected households distributed across the city. From 2009 to 2013, ovitraps (n = 177) were sampled weekly to monitor the oviposition activity of Ae. aegypti. We explored seasonal and interannual dynamics of entomological variables and dengue transmission. Cross correlation analysis was used to identify significant lag periods. Results: Aedes aegypti were detected over the entire study period, and abundance peaked during the summer months (January to March). We identified a considerable increase in the proportion of homes with juvenile Ae. aegypti over the study period (from 5.7% of homes in 2009–10 to 15.4% of homes in 2016–17). Aedes aegypti eggs per ovitrap and larval abundance were positively associated with temperature in the same month. Autochthonous dengue transmission peaked in April, following a peak in imported dengue cases in March; autochthonous dengue was not positively associated with vector or climate variables. Conclusions: This longitudinal study provides insights into the complex dynamics of arbovirus transmission and vector populations in a temperate region of arbovirus emergence. Our findings suggest that Córdoba is well suited for arbovirus disease transmission, given the stable and abundant vector populations. Further studies are needed to better understand the role of regional human movement.

Obtaining protoanemonin through selective oxidation of Dfructose and 5-(hydroxymethyl) furfural in a self-catalysed reaction Martínez, José J.; Páez, Luis A.; Gutiérrez, Luisa F.; Pardo Cuervo, Oscar H.; Rojas, Hugo A.; Romanelli, Gustavo Pablo; Portilla, Jaime; Castillo, Juan Carlos; Gamboa Becerra, Diana Paola Although different ways of converting 5- (hydroxymethyl)furfural (1) to various substrates with high value have been sought, few transformations have obtained building blocks that can be very useful in the area of fine chemistry. Herein, we report the synthesis of protoanemonin (5-methylenefuran-2(5H)- one) from D-fructose via compound (1), a versatile γalkylidenebutenolide, using an efficient self-catalysed process with formic acid, with high reaction performance and selectivity (up to 94% yield and 98% conversion from (1), while 28% yield from Dfructose). This efficient and simple operational process involved a two-phase aqueous-organic system between chlorinated solvents (CHxCly) and hydrogen peroxide as the initial oxidizing agent. The reaction presents a key cleavage in the 5-hydroxymethyl moiety of (1), due to the Baeyer-Villiger oxidation (BVO) process that generates formic acid in situ. Ultimately, DFF and HMF were successfully obtained in 80% and 98% yield, respectively, starting from D-fructose and using Preyssler heteropolyacids as Brønsted acid catalysts under an atmosphere of oxygen in the absence of hydrogen peroxide.

Nanostructured electrode using CMK-8/CuNPs platform for herbicide detection in environmental samples Regiart, Daniel Matias Gaston; Fernández Baldo, Martín Alejandro; Pamela Navarro; Pereira, Sirley Vanesa; Raba, Julio; Messina, Germán Alejandro A simple and sensitive nanostructured electrode was designed by electrodepositing copper nanoparticles (CuNPs) on a screen-printed carbon electrode (SPCE) modified with an ordered mesoporous carbon (CMK-8) in order to detect glyphosate (GLY) in river water samples. CMK-8 was immobilized onto an SPCE using chitosan polymer (CH) as a binder, followed by CuNPs electrodeposition. CuNPs/CMK-8-CH/SPCE was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, transmission electron microscopy, scanning electron microscopy, energy dispersive spectrometry, and N2 adsorption–desorption isotherms. CMK-8 has a high specific surface area, large pore volume, uniform mesostructure, good conductivity, and excellent electrochemical activity. This mesoporous carbon material provides the sensitivity for the indirectly electrochemical determination of GLY by square wave voltammetry. The anodic currents increased proportionally to the concentrations of GLY due to a complexation process. The detection limit achieved by the designed electrochemical device was 0.09 ng mL−1 with a linear range from 0.3 ng mL−1 to 19.75 ng mL−1 with intra and inter-assay coefficients of variation below 5%. This electrochemical platform represents an attractive strategy for on-site GLY determination in environmental samples.

On the sharp upper bound related to the weak Muckenhoupt–Wheeden conjecture Lerner, Andrei K.; Nazarov, Fedor; Ombrosi, Sheldy Javier We construct an example showing that the upper bound [w]A1log(e+[w]A1) for the L1(w)→L1,∞(w) norm of the Hilbert transform cannot be improved in general.

Espías, rusos y maximalistas en el verano de 1919: La Semana Trágica revisitada desde las fuentes diplomáticas y periodísticas; Spies, russians and maximalists in the summer of 1919: The Tragic Week revisited from the diplomatic and journalistic sources Koppmann, Walter Ludovico; Asquini, Sabrina Emilia El artículo propone revisitar la Semana Trágica de 1919 en Buenos Aires a partir del análisis sobre las fuentes de la diplomacia y el espionaje extranjeros en el país, problematizando las perspectivas y la bibliografía existente. El relevamiento de materiales poco explorados habilitan la formulación de nuevos interrogantes sobre un tema aparentemente «agotado» respecto del cual, no obstante, recientes trabajos han demostrado que aún quedan diferentes aspectos por profundizar; The aim of this paper is to revisit the Tragic Week of 1919 in Buenos Aires, analyzing new sources that belong from the foreign diplomacy and the espionage. In addition, it examines the mainstreamperspectives and bibliography.The little-explored documents enables new questions on an apparently already-known subject, with respect to which, however, recent works have shown that there are still different aspects to deepen

A meta-analysis of SMEs literature based on the survey on access to finance of enterprises of the European central bank Martinez, Lisana Belén; Guercio, María Belén; Fernández Bariviera, Aurelio Small and Medium Enterprises (SMEs) are substantial contributors to employment and to the GDP growth in many countries. Therefore, understanding their difficulties to find appropriate financial resources are a key task for policy makers. Despite being a long-debated topic, there are still several gaps in the literature, probably due to the lack of empirical data. A relatively new database, the Survey of Access to Finance of Enterprises (SAFE) emerged after the subprime crisis. It is regularly conducted by the European Central Bank and can provide new information on SMEs financing. This paper conducts a meta-analysis of the literature based upon this survey, identifying key working hypothesis, methodologies and results.

Dificultades y reacciones positivas del proceso de enseñanza-aprendizaje en el contexto de la pandemia y del aislamiento obligatorio; Difficulties and positive reactions of the teaching-learning process in the context of the pandemic and of compulsory isolation Piantanida, Fernando Martín El presente texto tiene por objeto compartir las vivencias del proceso de enseñanza-aprendizaje de la cursada del Seminario Problemáticas del Mundo Mediterráneo durante el primer cuatrimestre del 2020, en el marco de la pandemia de COVID-19 y del aislamiento social, preventivo y obligatorio. Hace referencia a los diversos problemas que docentes y estudiantes han tenido que enfrentar. Señala las prácticas pedagógicas y recursos virtuales empleados a los efectos de intentar solucionarlos. Y destaca que, pese a las dificultades del contexto, no todo fue negativo, sino que también hubo aspectos positivos a rescatar, tales como una adaptación favorable a una modalidad virtual imprevista, compelida por las circunstancias, y el esfuerzo y compromiso de docentes y estudiantes para llevar a cabo la continuidad pedagógica en una coyuntura adversa.; The aim of this text is to share the experiences of the teaching-learning process of the seminar Problems of the Mediterranean World during the first semester of 2020, in the context of COVID-19 pandemic and of social, preventive and compulsory isolation. It refers to the various problems that teachers and students have had to face. It points out the pedagogical practices and virtual resources used in order to try to solve them. In spite of these difficulties, this article emphasizes that not everything has been negative. There were also positive aspects to be rescued, such as a favourable adaptation to an unforeseen virtual modality, compelled by the circumstances, and the effort and commitment of teachers and students to carry out the pedagogical continuity in an adverse situation.

1975: Muerto Franco, ¿qué debates y qué historias nos permitimos cuestionar?; 1975: Morto Franco, que debates e que histórias nos permitimos questionar? Minardi, Adriana Elizabeth Podríamos decir que, a partir de 1975, comienza en España un proceso de repatriación de la Historia que se impuso a través de tres olvidos: el de la República, el de la Guerra civil y el del Franquismo, pautado por la Transición democrática. Si entendemos que “toda narración, autobiográfica o novelesca, histórica o inventada depende de la memoria de alguien” (Vernon, 1989: 429), uno de los primeros actos en un relato es construir y representar una memoria ficticia e imitar el proceso rememorativo atendiendo a una concepción determinada de la memoria. Esta concepción depende de una estructura específica que conjuga una poética y una narrativa. En el siguiente artículo expondremos los debates acerca de las relaciones siempre conflictivas entre memoria, historia y política para luego proyectar el análisis a un texto autobiográfico.; Podemos dizer que, a partir de 1975, iniciou-se na Espanha um processo de repatriamento da história, imposto por três esquecimentos: o da República, o da Guerra Civil e o do franquismo, pautados pela transição democrática. Se entendermos que "toda narração, autobiográfica ou fictícia, histórica ou inventada depende da memória de alguém" (VERNON, 1989, p. 429), um dos primeiros atos de um relato é construir e representar uma memória fictícia e imitar o processo rememorativo atendendo a uma determinada concepção da memória. Essa concepção depende de uma estrutura específica que conjuga uma poética e uma narrativa. No artigo a seguir, exporemos os debates sobre as sempre conflitantes relações entre memória, história e política e projetaremos a análise a um texto autobiográfico.

Contenido total y disponibilidad de micronutrientes en suelos y excretas bovinas; Total content and availability of micronutrients in soils and livestock manure Ramos, Maria Laura; Moscuzza, Carlos Hernán; Fernandez Cirelli, Alicia The use of feedlot cattle manure appears as an important source of certain trace metals in soils that can be mobilized by water modifying the surface and groundwater quality. The current study is focused on assessing the availability of copper (Cu), zinc (Zn), cobalt (Co) and molybdenum (Mo) in manure from confined beef cattle systems and different soils of the Chaco-pampean plain, using a sequential extraction scheme. Soils and bovine manure coming from intensive (IS) and extensive (ES) beef cattle systems were collected. Total contents of Cu, Zn, Co and Mo were determined after microwave assisted acid digestion. Availability was evaluated through sequential extraction, including water-soluble and exchangeable fraction (EXCH), organic matter bound fraction (OM), inorganic precipitated fraction (INOR), and residual fraction (RES). Total Cu and Zn contents found in manure coming from IS were higher than the concentration of the aforementioned trace elements determined in all soils and manure analyzed from ES. EXCH-Cu only appears in IS cattle manure samples, while EXCH-Zn found in IS manure samples were higher than the soils samples analyzed. The higher levels of total and availability forms of Cu and Zn determined in IS manure compared to soils samples, require considering when this organic amendment is applied as fertilizer. These results indicate that the reuse of intensive cattle manure as fertilizer in agricultural areas could provide available forms of metals in soils and could contribute to reduce the environmental impact caused by the accumulation of excreta in pen soils during long periods in farms.; El uso de excretas provenientes de sistemas intensivos de engorde bovino aparece como una fuente importante de ciertos metales traza en suelos, los cuales pueden ser movilizados por escorrentía y lixiviado, modificando la calidad de cursos de agua superficial y subterránea. Este trabajo propone evaluar la disponibilidad de cobre (Cu), zinc (Zn), cobalto (Co) y molibdeno (Mo) en excretas provenientes de sistemas intensivos de engorde bovino y en diferentes suelos de la llanura Chaco-pampeana, utilizando un procedimiento de extracción secuencial. Se recolectaron muestras de suelos y excretas provenientes de sistemas intensivos (SI) y extensivos (SE) de producción de ganado vacuno. Los contenidos totales de Cu, Zn, Co y Mo se determinaron mediante digestión ácida asistida por microondas. La disponibilidad fue evaluada mediante un esquema de extracción secuencial que incluyó una fracción soluble en agua e intercambiable (INT), una fracción unida a materia orgánica (MO), una fracción inorgánica (INOR) y una fracción residual (RES). Los resultados obtenidos mostraron mayores contenidos totales y de la fracción intercambiable de Cu y Zn en excretas provenientes de SI respecto de las muestras de suelos y excretas provenientes de SE. Estos resultados indicarían que el uso de las excretas de sistemas intensivos de engorde bovino incrementaría las formas más disponibles de metales en suelos, de modo tal que su empleo como enmiendas orgánicas puede contribuir a reducir el impacto ambiental que origina su acumulación en suelos de corrales.

Neonicotinoids in global agriculture: Evidence for a new pesticide treadmill? Bakker, Lieneke; Werf, Wopke van der; Tittonell, Pablo; Wyckhuys, Kris A. G.; Bianchi, Felix J. J. A. Overreliance on synthetic insecticides in global agriculture is the outcome of a “pesticide treadmill,” in which insecticideinduced pest resistance development and the depletion of beneficial insect populations aggravate farmers’ pesticide dependencies. Examples of the pesticide treadmill have been witnessed repeatedly over the past seven decades, prompting the question whether the rapid uptake and usage patterns of neonicotinoid insecticides and their associated environmental impact are in accordance with this recurrent phenomenon. We hypothesize a conceptual framework in which treadmills are enforced by enabling or disabling drivers within four domains: pest management decisions at the farm level, characteristics of farming landscapes, science and technology, and societal demands. These drivers then tend to create a self-enforcing pesticide “lock-in.” We then analyze several post-1950s historical case studies with reference to this framework, e.g., those involving sprays of the highly hazardous DDT and methyl-parathion, in which the pesticide treadmill was initiated, sustained, and broken, and compare this with current patterns in neonicotinoid use. Historical case studies further illustrate how treadmills occur in three phases in which (i) a limited number of insecticides are routinely used, (ii) resistance development of pests results in the increased crop injury, prompting increased frequency of applications with a wider range of products, (iii) breaking out of the pesticide “lock-in” by policy change and adoption of alternative technologies that lowered chemical inputs and improved agro-ecosystem functioning. The analysis shows similarities as well as differences between neonicotinoid usage patterns and historic pesticide treadmills, and provides guidance on how to effectively avoid or dismantle pesticide treadmills in global agriculture.

Relevamiento de aspectos técnicos de pH y otros parámetros de calidad establecidos por Brasil para el ingreso de productos pesqueros congelados: Valores de referencia para merluza común (Merluccius hubbsi) Massa, Agueda Elena; Agüeria, Daniela Alejandra; Campos, Carmen Adriana; Czerner, Marina; Fernández, Lorena; Miscoria, Silvia Alejandra; Primost, Monica Angelina; Volpedo, Alejandra El presente informe se realiza en base a la solicitud realizada por el Servicio Nacional de Sanidad y Calidad Agroalimentaria (SENASA) para resolver la problemática relacionada con la exportación de pescado enfriado y congelado a la República Federativa de Brasil. SENASA solicita asistencia para relevar los aspectos científico-técnicos respecto a la validez de la determinación de pH como parámetro de frescura y determinar, de ser factible, valores de referencia para las especies ícticas argentinas. En este sentido la Red de Seguridad Alimentaria de CONICET (RSA) ha conformado un grupo ad hoc interdisciplinario e interinstitucional que ha realizado un relevamiento y análisis de las publicaciones disponibles relacionadas con diferentes aspectos técnicos de pH y otros parámetros de calidad (nitrógeno básico volátil total NBVT, fósforo total, contenido de sodio y de potasio, relación humedad/proteínas, niveles de histamina) utilizados en productos pesqueros congelados, particularmente para merluza común (Merluccius hubbsi). Además, se hizo un relevamiento de las normativas de Argentina y Brasil, así también como de disposiciones internacionales (USA, Canadá, Unión Europea) en relación a valores de referencia pH y de otros parámetros de calidad aplicados a productos pesqueros congelados.

Possible Assessment of Calf Venous Pump Efficiency by Computational Fluid Dynamics Approach Niccolini, Gianni; Manuello, Andrea; Capone, Antonio; Marongiu, Giuseppe; Dell'osa, Antonio Héctor; Fois, Andrea; Velluzzi, Fernanda; Concu, Alberto Three-dimensional simulations of peripheral, deep venous flow during muscular exercise in limbs of healthy subjects and in those with venous dysfunction were carried out by a computational fluid-dynamics (CFD) approach using the STAR CCM + platform. The aim was to assess the effects of valvular incompetence on the venous calf pump efficiency. The model idealizes the lower limb circulation by a single artery, a capillary bed represented by a porous region and a single vein. The focus is on a segment of the circuit which mimics a typical deep vein at the level of the calf muscle, such as the right posterior tibial vein. Valves are idealized as ball valves, and periodic muscle contractions are given by imposing time-dependent boundary conditions to the calf segment wall. Flow measurements were performed in two cross-sections downstream and upstream of the calf pump. Model results demonstrate a reduced venous return for incompetent valves during calf exercise. Two different degrees of valvular incompetence are considered, by restricting the motion of one or both valves. Model results showed that only the proximal valve is critical, with a 30% reduction of venous return during calf exercise in case of valvular incompetence: the net flow volume ejected by the calf in central direction was 0.14 mL per working cycle, against 0.2 mL for simulated healthy limbs. This finding appeared to be consistent with a 25% reduction of the calf ejection fraction, experimentally observed in chronic venous disease limbs compared with healthy limbs.

Immunotherapy for Hepatocellular Carcinoma: Is Latin America Ready for Primetime? Mazzolini Rizzo, Guillermo Daniel; Iracheta, Alexis; Malvicini, Mariana; Bayo Fina, Juan Miguel Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death worldwide, and its mortality is increasing steadily.1 HCC incidence has grown in the last twenty years driven at least in part by the epidemic of nonalcoholic fatty liver disease (NAFLD).2 Unfortunately, overall survival rate for patients with HCC at 5 years is near 18%, which reflects how complex and resistant to systemic therapies this devastating disease is.2 Although new systemic drugs have been approved for advanced HCC in the first and second line, prolonging overall survival beyond a year is still difficult.1

Erratum: Search for photons with energies above 1018 eV using the hybrid detector of the Pierre Auger Observatory Aab, A.; Abreu, P.; Aglietta, M.; Al Samarai, I.; Albuquerque, I. F. M.; Allekotte, Ingomar; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Anastasi, G. A.; Anchordoqui, Luis A.; Andrada, B.; Andringa, S.; Aramo, C.; Arqueros, F.; Arsene, N.; Asorey, Hernán Gonzalo; Assis, P.; Aublin, J.; Avila, G.; Badescu, A. M.; Balaceanu, A.; Barreira Luz, R. J.; Beatty, J. J.; Becker, K. H.; Bellido, J.A.; Berat, C.; Bertaina, M. E.; Bertou, Xavier Pierre Louis; Sciutto, Sergio Juan 1 Exposure calculation Due to a mistake in the numerical integration following eq. (6.2) of the original article [1], the exposure shown in figure 5 of the original article was incorrect. The correct exposure is shown in figure 1. 2 Upper limits on the integral photon flux and fraction The incorrect exposure affects the calculation of the upper limits on the integral photon flux following eq. (6.1) of the original article. The correct values for the upper limits are 0.038, 0.010, 0.009, 0.008 and 0.007 km−2 sr−1 yr−1 for threshold energies of 1, 2, 3, 5 and 10 EeV. The correct values for the upper limits on the integral photon fraction subsequently derived are 0.14 %, 0.17 %, 0.42 %, 0.86 % and 2.9 % for the same threshold energies. 3 Author list The author list of this erratum also corrects a mistake made in the original article, where F. Zuccarello was missing and Z. Zong was listed twice.

Swimming behavior and performance of the marsh rat Holochilus vulpinus (Brants, 1827) (Cricetidae, Sigmodontinae) Torres Monges, Julio Cesar; Santori, Ricardo T.; Rocha Barbosa, Oscar; Candela, Adriana Magdalena; Pardiñas, Ulyses F. J. Semiaquatic habits evolved in several Sigmodontinae rodent species, but this issue remains poorly studied. The marsh rat Holochilus vulpinus (Brants, 1827) has been associated with palustrine wetland environments and exhibits several morphological traits related to the semiaquatic habit. However, its swimming behavior and the way its morphological specializations contribute to it have not been evaluated so far in this species. This note focuses on describing and quantifying the swimming behavior and swimming performance of H. vulpinus. In order to address these issues, five individuals of H. vulpinus, four adults and one subadult, were filmed while swimming and their performance was quantified. The obtained results indicate that the swimming mode is bipedal paddling, alternating the stroke of the hind feet. The quantitative indicators also qualify H. vulpinus as a good swimmer compared to other terrestrial and semiaquatic mammals.

Plastic ingestion and dispersion by vultures may produce plastic islands in natural areas Ballejo, Fernando; Plaza, Pablo; Speziale, Karina Lilian; Lambertucci, Agustina P.; Lambertucci, Sergio Agustin Rubbish dumps can become an important environmental source of plastic. Several species feed on organic waste from these sites, but at the same time are exposed to non-organic materials. Species that can gather food in these sites might at the same time disperse waste consumed, but this has rarely been evaluated. We compare the occurrence of plastic debris in regurgitated pellets of three sympatric vultures from northwest Patagonia, Andean condors (Vultur gryphus), black vultures (Coragyps atratus) and turkey vultures (Cathartes aura), foraging in different degrees of humanized sites. We also evaluate the influence of rubbish dumps in the presence of plastic debris in pellets of the studied species and their potential role in spreading plastic to the environment. Most synthetic material present in pellets was plastic. Pellets of Andean condors, which avoid disturbed anthropic sites in this area, showed almost no plastic debris compared with the other sympatric vulture species, suggesting an influence of the foraging habits on plastic ingestion. For black and turkey vultures, we found that rubbish dumps may be an important source of plastic. The occurrence of plastic debris in pellets of black vultures sampled in 2010 and 2020 increased, probably associated with the increase in urbanization and waste production in the study area. Avian scavengers were exposed to and are able to transport plastic to distant communal roosts generating “plastic islands”. It is necessary to reduce plastic generation and better waste management practices to avoid species and environments to be affected by this pollutant.

Sex differences in the use of spatial cues in two avian brood parasites Lois Milevicich, Jimena; Kacelnik, Alex; Reboreda, Juan Carlos Shiny and screaming cowbirds are avian interspecific brood parasites that locate and prospect host nests in daylight and return from one to several days later to lay an egg during the pre-dawn twilight. Thus, during nest location and prospecting, both location information and visual features are available, but the latter become less salient in the low-light conditions when the nests are visited for laying. This raises the question of how these different sources of information interact, and whether this reflects different behavioural specializations across sexes. Differences are expected, because in shiny cowbirds, females act alone, but in screaming cowbirds, both sexes make exploratory and laying nest visits together. We trained females and males of shiny and screaming cowbird to locate a food source signalled by both colour and position (cues associated), and evaluated performance after displacing the colour cue to make it misleading (cues dissociated). There were no sex or species differences in acquisition performance while the cues were associated. When the colour cue was relocated, individuals of both sexes and species located the food source making fewer visits to non-baited wells than expected by chance, indicating that they all retained the position as an informative cue. In this phase, however, shiny cowbird females, but not screaming, outperformed conspecific males, visiting fewer non-baited wells before finding the food location and making straighter paths in the search. These results are consistent with a greater reliance on spatial memory, as expected from the shiny cowbird female’s specialization on nest location behaviour.

La dictadura militar en el campo chaqueño: una aproximación a sus características, temporalidades y magnitudes; The military dictatorship in the Chaco countryside: an approximation to its characteristics, temporalities and magnitudes Calvo, Claudia Hacia fines de los años sesenta el campesinado del noreste del país, nucleado alrededor de los complejos agroindustriales, asistió a un proceso de movilización política. En noviembre de 1970 en Chaco se crearon las Ligas Agrarias, tras la confluencia de la Unión de Jóvenes cooperativistas y el Movimiento Rural de Acción Católica. Impulsaron la distribución y titulación de la tierra, la regulación de la comercialización y la producción por parte del Estado. Enfrentaron a los monopolios de la comercialización y al poder terrateniente. Partícipes del proceso de radicalización popular, las Ligas sufrieron la persecución política desde inicios de 1975. Acusados de subversivos, sus principales dirigentes fueron detenidos y las bases acosadas por fuerzas parapoliciales. Con el golpe de Estado de 1976 fueron desmanteladas. Este artículo analiza las características que asumió la represión en el campo a partir del golpe de Estado de 1976, atendiendo a las continuidades y rupturas que supuso el quiebre institucional en la dinámica y características de la violencia estatal y para estatal sobre las Ligas ya desde comienzos de la década. El trabajo apunta a reflexionar sobre la el modo en que se inscribió regionalmente el terrorismo de Estado antes y después del golpe.; Towards the end of the 1960s, the peasantry in the northeast of the country, nucleated around the agro-industrial complexes, witnessed a process of political mobilization. In November 1970 in Chaco the Agrarian Leagues were created, after the confluence of the Union of Young Cooperatives and the Rural Movement of Catholic Action. They promoted the distribution and titling of land, the regulation of commercialization and production by the State. They faced the monopolies of commercialization and landlord power. Participants in the process of popular radicalization, the Leagues suffered political persecution since the beginning of 1975. Accused of being subversives, their main leaders were arrested and the bases harassed by para-police forces. With the 1976 coup they were dismantled. This article analyzes the characteristics that repression assumed in the countryside as of the 1976 coup d’état, taking into account the continuities and ruptures that the institutional breakdown in the dynamics and characteristics of state and para-state violence on the Leagues since the beginning of the decade. The work aims to reflect on the way in which State terrorism was registered regionally before and after the coup.