Recursos para una historia de las culturas musicales: la Revista de la Asociación Wagneriana de Buenos Aires (1914-1926); Recursos para uma história das culturas musicais: a Revista de la Asociación Wagneriana de Buenos Aires (1914-1926); Resources for a History of Musical Cultures: The Revista de la Asociación Wagneriana de Buenos Aires (1914-1926) Irurzun, Maria Josefina El objetivo general del presente trabajo es complejizar los abordajes tradicionales de las revistas de música para concebirlas como dispositivos y prácticas de acción social que caracterizan a las culturas musicales, así como interpelan diversas esferas de la opinión pública. Para ello, se analiza el caso de la Revista de la Asociación Wagneriana de Buenos Aires (publicada por la Asociación homónima), a partir de la periodización de los momentos vitales o editoriales de la misma, atendiendo a la pluralidad de contextos y los aspectos relacionados con ellos, su forma de organización colectiva como espacio de enunciación, sus modos de ser, estilo, recursos, etc. Se argumenta que, si bien la dependencia de la publicación respecto a la entidad condicionó su forma y contenido, operó también como una institución en sí misma (“una tribuna de arte y cultura”). Por último, se señalan las múltiples posibilidades de indagación de las revistas de música (con frecuencia concebidas como “manifestaciones” de procesos que ocurren por fuera de ellas), la dinámica de sus cambios e intervenciones y las distintas significaciones –otorgadas a través del tiempo–, que las convierten también en revistas culturales.; O objetivo geral do presente trabalho é complexificar as abordagens tradicionais das revistas de música para concebê-las como dispositivos e práticas de ação social que caracterizam as culturas musicais, assim como interpelam diversas esferas de opinião pública. Para tal, analisa-se o caso da Revista de la Asociación Wagneriana de Buenos Aires (publicada pela associação homónima), a partir da periodização dos momentos vitais ou editoriais da mesma, atendendo à pluralidade de contextos e aspectos relacionados com eles, sua forma de organização coletiva como espaço de enunciação, seus modos de ser, estilo, recursos, etc. Argumenta-se que, embora a dependência da revista em relação à entidade condicionou a sua forma e conteúdo, operou também como uma instituição em si mesma (“uma tribuna de arte e cultura”). Por último, assinala-se a dificuldade inerente à indagação das revistas de música (com frequência concebidas como “manifestações” de processos que ocorrem por fora delas), a dinâmica de suas mudanças e intervenções e as diferentes significações –outorgadas através do tempo– que as convertem também em revistas culturais.; The main objective of this paper is to rethink traditional approaches by music magazines and conceive of them as social action devices and practices that gave distinctive characteristics to musical cultures and took place in different spheres of public opinion. The analysis is based on the Revista de la Asociación Wagneriana de Buenos Aires (published by the association of the same name), starting from the periodization of its vital or editorial phases, taking into account the plurality of contexts and the aspects related to them, their collective organization as a space of enunciation, their style, resources, etc. It was found that, while the institutional dependency of the publication conditioned its form and content, it also operated as an entity in itself (“a forum for art and culture”). Finally, attention is drawn to the multiple possibilities of researching music journals (often conceived as “manifestations” of processes occurring outside them), the dynamics of their changes and interventions, and the different meanings granted through time-, that turn them into cultural magazines.

¿Cuándo podemos fijar la fecha de esquila? Gonzalez, Ezequiel Bernardo; Easdale, Marcos Horacio; Sacchero, Diego Mariano La elección del momento de esquila es una de las decisiones de manejo predial más importante de los sistemas ganaderos ovinos. En este artículo presentamos información actualizada de la distribución temporal y espacial de las esquilas en la provincia de Río Negro.

Linear segmented polyurethanes. III. Mathematical model for a two-steps polymerization Polo, Mara Lis; Spontón, Marisa Elisabet; Huespe, Alfredo Edmundo; Estenoz, Diana Alejandra; Meira, Gregorio Raul In the first article of this sequel (J. Appl. Polym. Sci., 2018, 135, 45747), an experimental and theoretical investigation was developed on the two-steps synthesis of linear segmented thermoplastic polyurethanes. The reactions were carried out at 60°C, with methylene diphenyl diisocyanate (MDI), two poly(tetramethylene oxide) macrodiols, and 1,4-butanediol (BD) as chain extender. In our second article (J. Appl. Polym. Sci., 2019, 136, 46946), a mathematical model for the prepolymerization was developed, that involved integrating a differential equation for each generated polymer species. The present article extends such model, and predicts the molecular structure along the finishing stage. In each stage, the new model first solves the molar balances at polymer topologies level (i.e.,: Disregarding the molar mass distribution [MMD] of the reacted macrodiol chains), and then calculates the MMD of the evolving polymer and its main subsets through an algebraic convolution procedure. The model reproduces the prepolymerization predictions of our previous article, but is three orders of magnitude faster. In the finishing stage, up to 156,000 polymer topologies and 4.53 × 108 polymer species were calculated; and the rate constant was readjusted to (k2 = 0.00129 L mol−1 s−1), in order to fit the measured MMDs.

El "siempreverde" (Ligustrum lucidum) ¿altera la composición de las comunidades de hongos micorrícicos arbusculares en el chaco serrano? Borda, Valentina; Cofré, María Noelia; Longo, Maria Silvana; Grilli, Gabriel; Urcelay, Roberto Carlos Las invasiones biológicas representan una gran amenaza para la biodiversidad y la integridad de los ecosistemas dado que alteran las comunidades bióticas. Entre las comunidades bióticas del suelo se destacan los hongos micorrícicos arbusculares (HMA), que establecen asociaciones simbióticas con la mayoría de las plantas terrestres. Las especies de HMA no responden del mismo modo a los cambios ambientales, por lo que se propuso la existencia de grupos de especies de HMA con estrategias ecológicas compartidas (ruderales, competidoras y estrés tolerantes). Las plantas invasoras son capaces de alterar las comunidades de HMA para su propio beneficio. Este podría ser el caso del ?siempreverde? (Ligustrum lucidum), un árbol asiático que invade numerosos sectores de la Argentina y forma, en algunas zonas, bosques monoespecíficos densos. En este estudio se compararon las comunidades de esporas de HMA entre bosques monoespecíficos de siempreverde y bosques chaqueños serranos nativos. Se seleccionaron 6 áreas con ambos tipos de bosque. De cada área se tomaron muestras de suelo, a las que se les midieron características físico-químicas y se les extrajeron las esporas de HMA. De acuerdo con lo esperado, la composición de las comunidades de esporas de estos bosques monoespecíficos fue diferente a la presente en suelos de bosques nativos. La riqueza de morfoespecies de esporas de HMA no mostró diferencias entre ambos tipos de bosque, pero la abundancia total fue mayor en los suelos de bosque de siempreverde, que presentan un mayor número de esporas de especies ruderales. Este estudio provee evidencia que sugiere que la expansión del siempreverde altera las comunidades de esporas de HMA y algunas propiedades químicas del suelo. Estos cambios posiblemente sean parte del mecanismo que promueve la formación de bosques monoespecíficos.

Riqueza potencial de murciélagos en el sur de las Yungas: aportes para la conservación de especies; Bat potential species richness in the southern Yungas: contribution to the conservationof species Castilla, María Cecilia; Cuyckens, Griet An Erica; Zucarelli, Verónica; Díaz, María Mónica Dentro de las Yungas en Argentina, la porción austral presenta ecotonos con eco-regionesmás áridas como el Chaco, la Puna y el Monte de Sierras y Bolsones. Posee alta diversidad de murciélagos, pero la riqueza disminuye drásticamente encima de los 23°S a 24°S. Este trabajo deriva de un estudio acerca de una colonia de Tadarida brasiliensis ubicada en el Dique Escaba (Tucumán), reconocida como Sitio de Importancia para la Conservación de los Murciélagos (SICOM). El objetivo fue evaluar, desde los factores bioclimáticos, la distribución y riqueza de especies de murciélagos en la porción austral de las Yungas, para contextualizar la importancia de ensambles locales y la utilización de la riqueza potencial como insumo para la designación de Áreas de Importancia para la Conservación de los Murciélagos (AICOMs). A partir de registros de presencia se estimaron distribuciones potenciales mediante el software MaxEnt, para lo quese seleccionaron previamente las variables mediante un Análisis de Componente Principales (pendiente, rango anual de la temperatura y temperatura media del trimestre más frío). El mapa de riqueza de especies se obtuvo sumando los modelos con un buen rendimiento y puntos de presencia de especies no modeladas. Se registraron 27 especies de murciélagos predominantemente insectívoras. La riqueza potencial de especies aumentó asociada a la distribución las Yungas, los cordones montañosos y los ecotonos con las zonas áridas.Los modelos de distribución son buenas herramientas para identificar AICOMs en función de su riqueza potencial, como los alrededores del Dique de Escaba (Tucumán)-Cuesta la Higuerilla (Catamarca) y la cuesta del Totoral y Dique Sumampa (Catamarca), donde se han realizado relevamientos de murciélagos y por eso se han declarado como tales.; In Argentina, the Yungas austral portion presents ecotones with arid eco-regions such as Chaco,Puna, and Monte of Mountains and Isolated Valley. It has a high diversity of bats, but the richness decreasesdrastically above 23°S and 24°S. This research derives from a study on a colony ofTadarida brasiliensislocatedin the Escaba Dam (Tucumán), and recognized as an Important Site for Bat Conservation (SICOM in Spanish).The objective was to assess, from bioclimatic factors, the distribution and richness of bat species in thesouthern portion of the Yungas, to contextualize the importance of local assemblages, and the use of potentialrichness as an input for the designation of Important Areas for Bat Conservation (AICOMs in Spanish). Fromthe presence records, potential distributions were estimated using the MaxEnt software, for which the variableswere previously selected through a Principal Component Analysis (slope, annual temperature range, andaverage temperature of the coldest quarter). The species richness map was obtained by adding the signi cantmodels and points of presence of non-modeled species. 27 species of bats predominantly insectivorous wererecorded. Potential species richness increased within the Yungas, across mountain ranges and at the ecotoneswith arid zones. Distribution models are appropriate tools to detect AICOMs based on their potential richness,such as the surroundings of the Escaba Dam (Tucumán) - Cuesta Higuerilla (Catamarca), and the Totoralslope and Sumampa Dam (Catamarca), where bat surveys have been performed and thereafter, they have beendeclared as such.

Regional development gaps in Argentina: A multidimensional approach to identify the location of policy priorities Niembro, Andrés Alberto; Sarmiento, Jesica Isabel Spatial inequalities within Latin American countries have historically attracted the interest ofacademics, policy-makers, and international agencies. This article aims to provide amultidimensional diagnosis of provincial development gaps in Argentina, in order to identifythe location of policy priorities. Therefore, we built a large database, which covers sevendevelopment dimensions, and applied multivariate analysis techniques to overcome someanalytical limitations of previous studies. Results show the stability of provincial developmentgaps between 2003 and 2013 and some heterogeneity within geographic regions. Instead,cluster analysis offers a better classification of Argentine provinces according to theirdevelopment gaps, which can help the government to prioritize the places wheredevelopment policies are strategic.

Designing a wider superelastic window la Roca, Paulo Matías; Sade Lichtmann, Marcos Leonel Conventional metal alloys can only recover their original shape if subjected to very small elastic deformations. Superelastic alloys (also named pseudoelastic alloys) can recover their shape after deformations as great as 20% (1) just by unloading the force on the material. They are part of the larger group of shape-memory alloys but do not require a temperature change for recovery, and they have found applications in areas including robotics, structural engineering of buildings, and aerospace engineering (2, 3). A superelastic alloy usually exhibits this property only over a well-determined and often small temperature range normally called a “superelastic window.” On page 855 of this issue, Xia et al. (4) describe superelastic “invar” alloys with functional properties that are independent of temperature over the largest superelastic window reported, from 10 to 473 K.

Advantages of rainfall partitioning by the global invader Ligustrum lucidum over the dominant native Lithraea molleoides in a dry forest Whitworth Hulse, Juan Ignacio; Magliano, Patricio Nicolás; Zeballos, Sebastián Rodolfo; Gurvich, Diego Ezequiel; Spalazzi, María Florencia; Kowaljow, Esteban Vegetation canopy plays a key role in the local water balance by partitioning rainfall into interception, throughfall and stemflow in dry forests. Many invasive plants have the capacity to replace native species and alter the net amount and spatial distribution of rainfall reaching the soil. In this paper, we aimed to compare the rainfall partitioning for the invader Ligustrum lucidum and the dominant native Lithraea molleoides, to evaluate the influence of morphological characteristics on stemflow generation in both species, and to explore spatio-temporal patterns of throughfall at stand scale. Stemflow percentage for L. lucidum was hugely higher than for L. molleoides (18 and 1%, respectively), which overcompensated its lower throughfall percentage (58.1 and 68.6%, respectively). Interception losses were lower for L. lucidum than for L. molleoides (23.2 and 30.6%, respectively). The minimum rainfall amount needed to generate throughfall and stemflow was 1.8 and 0.5 mm for L. lucidum, while 2.2 and 7.2 mm for L. molleoides. The differences in morphological characteristics between species mainly explained the stemflow generation. The increment on tree basal area, projected canopy area, and number of branches favored stemflow in L. lucidum, but not in L. molleoides. The throughfall spatial patterns showed that the dripping from different canopy densities was homogenous in L. lucidum stands, whereas throughfall increase towards more opened-canopies in L. molleoides stands. Lateral inflows were registered from small-scale crown sections at both forest stands, but less frequent in L. lucidum stands. The time stability of throughfall pattern differed between forest stands. Based on our results, relatively higher stemflow and lower interception losses for L. lucidum than for L. Molleoides may represent a competitive advantage in terms of plant invasion in water-limited ecosystems. These findings highlight the need for further inquiries determining the underlying role of rainfall partitioning in the invasion process of woody species.

Reflexiones sobre Responsabilidad Internacional de un Estado por la propagación del COVID-19 Castillo Argañarás, Luis Fernando Al surgir la enfermedad de COVID-19, el Estado donde se originó, no cumplió con las obligaciones del Reglamento Sanitario Internacional (2005) de la Organización Mundial de la Salud. Frente a este hecho ¿Surge responsabilidad internacional conforme la Resolución 56/83 de Asamblea General de la ONU del año 2001?.

Una App para conocer la calidad de vida de cualquier lugar de la República Argentina Velázquez, Guillermo Ángel; Zunino Suarez, Alejandro Octavio; Mikkelsen, Claudia Andrea; Linares, Santiago; Celemin, Juan Pablo; la Macchia, Maria Lorena; Manzano, Fernando; Tisnés, Adela Durante las últimas décadas, las innovaciones tecnológicas y transformaciones sociales están promoviendo un cambio de paradigma en la divulgación científica, en donde, la interactividad, la colaboración, el acceso remoto a la información y la liberación progresiva de los datos son sus elementos más representativos. Dentro de este proceso evolutivo, el campo de la Información Geográfica no ha quedado exceptuado, sino que por el contrario, ha sido una de las áreas más impactadas por el aumento de la capacidad computacional, dando origen a un número creciente de nuevas bases de datos, accesibilidad digital a las mismas y algoritmos de consulta y transformación de dicha información geográfica que poco a poco van reemplazando a aquella almacenada en los tradicionales mapas analógicos…

Experience and results with a telehealth treatment program in patients with cognitive disorders during the COVID-19 pandemic Dorman, Guido; Alvarez Dengra, Agustín; Fiorini, Adriana; Failla, Belén; Vallejos, Florencia; Pontello, Noelia; Roca, María; Bustin, Julian The COVID‐19 pandemic has led to the adoption of social quarantine measures in numerous countries. In this context, both COVID‐19 and quarantine can have a substantial impact in the mental health of affected populations. Health care services have had to adapt themselves to this new reality.

The impact of an early strict nationwide lockdown on the pattern of consultation for neurological diseases Calandri, I.L.; Hawkes, Maximiliano Alberto; Marrodán, María Dolores; Ameriso, Sebastian Francisco; Correale, Jorge; Allegri, Ricardo Francisco A massive disruption of healthcare systems, a profound economic depressionand a distressing social situation [1]. Most countries enteredinto a lockdown in an attempt to slow the spread of the virus once theywere already suffering a serious hit. Based on the experience observed in Europe, Argentina closed its borders on March 15thonly one week afterthe firstperson died of COVID-19, and implemented an early nationwidelockdown limiting the circulation of 90% of its population, on March20th, with 128 cases and 3 deaths of COVID-19 [2-3]. Most health careresources were reassigned in anticipation of a catastrophic situation. Themassive communication media and the medical community warned thepopulation about the necessity of avoiding ?non-urgent? consults to theemergency rooms to avoid the overload of the system.To evaluate the impact of the national lockdown policy during theCOVID-19 pandemic,we compared the pattern of consultation to a tertiaryneurological center.Patients who attended to our ED have primaryneurological complaints or presented chronic neurological conditionswith varied medical problems. The period evaluated was the quarantineperiod (March 20st to April 26th 2020) with the same timeframeof 2019.Descriptive summaries are presented as mean or median (standarddeviation, SD) for continuous variables and proportions for categoricalvariables. The t-test or Mann-Whitney test were used to comparequantitative variables as appropriate. Pearson Chi-Square test or Fisher´sexact test were used to comparefrequencies of categorical variables asappropriate.A p-value < 0.05 was considered significant. The statisticalanalysis was performed with R-3.6.1, and the tydiverse, ggpubr, andggplot2 packages. This research has been approved by the Institutional Ethics Committee.

Soybean yield, protein content and oil quality in response to interaction of arbuscular mycorrhizal fungi and native microbial populations from mono and rotation-cropped soils Marro, Nicolás Alejandro; Cofré, María Noelia; Grilli, Gabriel; Alvarez, Carolina; Labuckas, Diana Ondina; Maestri, Damián; Urcelay, Roberto Carlos Two main soil management practices are generally used for soybean production: monoculture (MC) and crop rotation (CR). These strategies have different impacts on soil microbial communities. Among them, arbuscular mycorrhizal fungi (AMF) are well known to provide access to nutrients in a majority of cultivated plants. AMF communities have been shown to be more diverse in CR than in MC. Because AMF species differ in their effects on nutrition and development of plants, it could be expected that soil biota from different soil management practices affect soybean yield and quality. Therefore the objective of this study was to examine the combined effects of soil microbial communities and soil management practices (MC and CR) on yield, protein content, and oil quality of soybean grown under greenhouse conditions. The effects of three soil treatments, namely: sterile (S); microorganisms without AMF (MO); and microorganisms with AMF (AMF) were evaluated. These treatments were applied to soils from two crop management practices (CR and MC). Sterile soil promoted lower numbers of pods and seed weight per plant in MC but not in CR. AMF showed increased seed protein content (12?14%) whereas MO presented increased oil concentration (20?27%) (mainly within CR). Soybean grown with AMF from CR soil showed significantly higher amounts of oleic acid (21?25%), and lower linoleic acid (9%) when compared with other treatments. Findings from this study suggest that soybean yield and quality are affected by crop management practices and soil biota composition. Further, these parameters should be considered at the time of selecting agricultural strategies.

Smaug membraneless organelles regulate mitochondrial function Fernández Alvarez, Ana Julia; Thomas, Maria Gabriela; Pascual, Malena Lucía; Habif, Martin; Pimentel, Jerónimo; Corbat, Agustín Andrés; Pessoa, Joao; la Spina, Pablo Ezequiel; Boscaglia, Lara; Plessis, Anne; Carmo Fonseca, Maria; Grecco, Hernan Edgardo; Casado Pinna, Marta; Boccaccio, Graciela Lidia Smaug is a conserved translational repressor that recognizes specific RNA motifs in a large number of mRNAs, including nuclear transcripts that encode mitochondrial enzymes. Smaug orthologs have been shown to form membraneless organelles (MLOs) in several organisms and cell types. Using single-molecule FISH we show here that SDHB and UQCRC1 mRNAs associate with Smaug1 MLOs in the human cell line U2OS. Simultaneous loss of function of Smaug1 and Smaug2 affects both mitochondrial respiration and mitochondrial network morphology. Deletion of specific Smaug1 protein regions resulted in impaired MLO formation that correlates with mitochondrial defects. In addition, rotenone but not the respiratory chain uncoupling agent CCCP rapidly induces Smaug1 MLO dissolution. Finally, metformin elicits a similar effect on Smaug1 MLOs and provokes the release of bounded mRNAs. We propose that mitochondrial activity affects Smaug1 MLO dynamics, thus allowing for regulation of nuclear mRNAs that encode key mitochondrial proteins.

Data governance: Organizing data for trustworthy Artificial Intelligence Janssen, Marijn; Brous, Paul; Estevez, Elsa Clara; Barbosa, Luís Soares; Janowski, Tomasz The rise of Big, Open and Linked Data (BOLD) enables Big Data Algorithmic Systems (BDAS) which are often based on machine learning, neural networks and other forms of Artificial Intelligence (AI). As such systems are increasingly requested to make decisions that are consequential to individuals, communities and society at large, their failures cannot be tolerated, and they are subject to stringent regulatory and ethical requirements. However, they all rely on data which is not only big, open and linked but varied, dynamic and streamed at high speeds in real-time. Managing such data is challenging. To overcome such challenges and utilize opportunities for BDAS, organizations are increasingly developing advanced data governance capabilities. This paper reviews challenges and approaches to data governance for such systems, and proposes a framework for data governance for trustworthy BDAS. The framework promotes the stewardship of data, processes and algorithms, the controlled opening of data and algorithms to enable external scrutiny, trusted information sharing within and between organizations, risk-based governance, system-level controls, and data control through shared ownership and self-sovereign identities. The framework is based on 13 design principles and is proposed incrementally, for a single organization and multiple networked organizations.

Non-polar extracts of Nicotiana glauca (Solanaceae) induce apoptosis in human rhabdomyosarcoma cells Musso, Florencia Antonella; Pronsato, Lucía; Milanesi, Lorena Magdalena; Vasconsuelo, Andrea Anahi; Faraoni, María Belén Rhabdomyosarcoma (RMS) is the most common soft-tissue tumour in children andadolescents. It originates in normal skeletal muscle from myogenic cells that have failed tofully differentiate, and it usually has a poor prognosis. Current RMS therapy has manyadverse effects. Hence, new treatments are needed. Various pharmacological properties,such as analgesic, antineoplastic, antimicrobial, and antiparasitic properties, have beendemonstrated in species of the Solanaceae family. We performed ethanolic extraction fromleaves of Nicotiana glauca (Solanaceae), and the extract was successively partitioned withn-hexane, chloroform, and ethyl acetate. We evaluated the effects of extracts on RMScells, and we found that the extracts trigger apoptosis. By bio-guided fractionation assays,we identified the apoptotic agents. Morphological assessment after apoptotic cell inductionof cultured cells, mitochondrial and nuclear morphology by Mitotracker, and 4,6-diamidino-2-phenylindole (DAPI) staining, respectively, were analysed in fluorescentmicroscopy. The capacity of the cells to migrate or proliferate was analysed by the Petitassay, followed by methylene blue staining. NMR and GC-MS spectrometry were used toidentify palmitic acid and scopoletin as the phytochemicals responsible for the observedeffects. These results indicate that these compounds are apoptotic inducers and they couldbe useful as chemotherapeutic agents against muscle tumours.; Rabdomiossarcoma (RMS) é o tumor de tecidos moles mais comum em crianças e adolescentes. Ele se origina no músculo esquelético normal a partir de las células miogênicas que no conseguiram-se diferenciar completamente e pelo general tem um prognóstico ruim. A terapia atual com RMS tem muitos efeitos adversos e portanto, novos tratamentos são necessários. Várias propriedades farmacológicas, como propriedades analgésica, antineoplásica, antimicrobiana e antiparasitária, foram demostradas em espécies da família Solanaceae. Neste trabalho, foi realizada a extração etanólica das folhas de Nicotiana glauca (Solanaceae), eo extrato foi particionado sucessivamente com n-hexano, clorofórmio y acetato de etila. Avaliamos os efeitos dos extratos nas células RMS e descobrimos que os extratos desencadeiam apoptose. Pelos ensaios de fracionamento bio-guiado, identificamos os agentes apoptóticos. Avaliação morfológica após indução da apoptose das células cultivadas ea morfologia mitocondrial e nuclear por coloração com Mitotracker e 4,6-diamidino-2-fenilindol (DAPI), respectivamente, foram analisadas com microscopia fluorescente. A capacidade das células para migrar ou proliferar foi analisada hair ensaio Petit, seguido pelacoloração com azul de metileno. Una espectrometría de RMN y GC-MS para uso utilizado para una identificación de ácido palmítico y una escopoletina como fitoquímicos responsáveis ​​pelos efeitos observados.

The origin of matter at the base of relativistic jets in active galactic nuclei Romero, Gustavo Esteban; Gutiérrez, Eduardo Mario The generation of relativistic jets in active sources such as blazars is a complex problem with many aspects, most of them still not fully understood. Relativistic jets are likely produced by the accretion of matter and magnetic fields onto spinning black holes. Ergospheric dragging effects launch a Poynting-dominated outflow in the polar directions of these systems. Observations with very high resolution of the jet in the nearby radio galaxy M87 and evidence of extremely fast variability in the non-thermal radiation of several other objects indicate that charged particles produce synchrotron emission and gamma rays very close to the base of the jet. How these particles are injected into the magnetically shielded outflow is a mystery. Here we explore the effects of various processes in the hot accretion inflow close to the black hole that might result in the copious production of neutral particles which, through annihilation and decay in the jet´s funnel, might load the outflow with mass and charged particles on scales of a few Schwarzschild radii.

On some graph classes related to perfect graphs: A survey Bonomo-Braberman, Flavia; Durán, Guillermo; Safe, Martin Dario; Wagler, Annegret K. Perfect graphs form a well-known class of graphs introduced by Berge in the 1960s in terms of a min–max type equality involving two famous graph parameters. In this work, we survey certain variants and subclasses of perfect graphs defined by means of min–max relations of other graph parameters; namely: clique-perfect, coordinated, and neighborhood-perfect graphs. We show the connection between graph classes and both hypergraph theory, the clique graph operator, and some other graph classes. We review different partial characterizations of them by forbidden induced subgraphs, present the previous results, and the main open problems. Computational complexity problems are also discussed.

Acute glyphosate exposure does not condition the response of microbial communities to a dry-rewetting disturbance in a soil with long history of glyphosate-based herbicides Allegrini, Marco; Gomez, Elena del Valle; Zabaloy, Maria Celina Dry-rewetting perturbations are natural disturbances in the edaphic environment and particularly in dryland cultivation areas. The interaction of this disturbance with glyphosate-based herbicides (GBHs) deserves special attention in the soil environment due to the intensification of agricultural practices and the acceleration of climate change with an intensified water cycle. The objective of this study was to assess the response of microbial communities in a soil with long history of GBHs to a secondary imposed perturbation (a single dry-rewetting event). A factorial microcosm study was conducted to evaluate the potential conditioning effect of an acute glyphosate exposure on the response to a following dry-rewetting event. A Respiratory Quotient (RQ) based on an ecologically relevant substrate (p-coumaric acid) and basal respiration was used as physiological indicator. Similarly, DNA-based analyses were considered, including quantitative PCR (qPCR) of functional sensitive microbial groups linked to cycles of carbon (Actinobacteria) and nitrogen (ammonia-oxidizing microorganisms), qPCR of total bacteria and denaturing gradient gel electrophoresis (DGGE) of ammonia-oxidizing bacteria (AOB). Significant effects of Herbicide and of Dry-rewetting perturbations were observed in the RQ and in the copy number of amoA gene of AOB, respectively. However, no significant interaction was observed between them when analyzing the physiological indicator and the copy number of the evaluated genes. PCR-DGGE results were not conclusive regarding a potential effect of Dry-rewetting × Herbicide interaction on AOB community structure, suggesting further analysis by deep sequencing of amoA gene. The results of this study indicate that the perturbation of an acute glyphosate exposure in a soil with long-history of this herbicide does not have a conditioning effect on the response to a subsequent dry-rewetting disturbance according to a physiological indicator or the quantified bacterial/archaeal genes. This is particularly relevant for the sustainability of soils in rainfed agriculture, where frequent exposure to GBHs along with intensification of hydrological cycles are expected to occur. Further studies considering multiple dry-rewetting disturbances and in different soil types should be conducted to simulate those conditions and to validate our results.

Potential threat of plastic waste during the navigation of ships through the Turkish straits Kaptan, Mehmet; Sivri, Nüket; Blettler, Martin Cesar Maria; Ugurlu, Özkan The Turkish Straits System (TSS) is a dangerous and narrow waterway extending between the Black Sea and the Aegean Sea, including the Bosphorus, the Dardanelles, and the Marmara Sea and the Gulf of Izmit. The western banks of the TSS constitute the geographic starting point of the European continent, while the banks to the east are the beginnings of the Asia. TSS is considered one of the most strategically significant waterways of the world. This waterway is the main trading routes linking the Black Sea riparian countries to the world markets. As a result, the density in marine traffic through the TSS has recently reached alarmingly high levels. The aim of this study was to estimate the amount of plastic waste generated aboard merchant ships during their passage through the TSS during the period 2006?2017. This potential resource of waste would potentially impact on the Marmara Sea and its natural environment. The results of this study revealed that merchant ships crossing the TSS generated an average of 187.6 m3 of plastic waste per year. This result suggests that the threat given by the ships crossing this strait is approximately 1% of the total amount of waste recorded in the TSS coastals.