Bridge in micron-sized Bi2Sr2CaCu2O8+y sample act as converging lens for vortices Puig, Joaquín; Cejas Bolecek, Néstor René; Aragón Sánchez, Jazmín; Dolz, Moira Ines; Konczykowski, Marcin; Fasano, Yanina We report on direct imaging of vortex matter nucleated in micron-sized Bi2Sr2CaCu2O8+y superconducting samples that incidentally present a bridge structure. We find that when nucleating vortices in a field-cooling condition the deck of the bridge acts as a converging lens for vortices. By means of Bitter decoration images allowing us to quantify the enhancement of vortex-vortex interaction energy per unit length in the deck of the bridge, we are able to estimate that the deck is thinner than ∼0.6 μm. We show that the structural properties of vortex matter nucleated in micron-sized thin samples are not significantly affected by sample-thickness variations of the order of half a micron, an important information for type-II superconductors-based mesoscopic technological devices.

Migraciones fílmicas: Análisis crítico de Aufstellung de Harun Farocki; Filmic migrations: Critical analysis of Aufstellung by Harun Farocki Molina, Manuel Este trabajo se propone realizar un análisis crítico del ensayo fílmico Aufstellung (2005) del director checo-alemán Harun Farocki, a través de tres puntos entrelazados: (1) En un nivel fílmico se propone pensar la reducción de la diversidad cultural de les inmigrantes turcos en la Alemania de posguerra en la construcción de un monigote; (2) en un nivel sociohistórico se intenta trazar la conexión entre la historia de la migración alemana que plantea el film con el contexto histórico de les trabajadores invitades o Gastarbeiters; (3) en un nivel estético-político se retoman las reflexiones del filósofo alemán Theodor W. Adorno a propósito de las palabras extranjeras, para interpretar Aufstellung bajo el concepto de extranjerismo. Luego, por último, se proponen una serie de reflexiones divergentes que permiten pensar la crítica de Aufstellung al nacionalismo de manera anacrónica y más allá de las fronteras alemanas.; This paper proposes a critical analysis of the film-essay Aufstellung (2005) by the Czech-German director Harun Farocki, through three intertwined points: (1) On a filmic level, it is proposed to think about the reduction of the cultural diversity of Turkish immigrants in post-war Germany in the construction of a muppet; (2) on a socio-historical level, it is attempted to trace the connection between the history of German migration that the film presents with the historical context of the guest workers or Gastarbeiters; (3) on an aesthetic-political level, the reflections of the German philosopher Theodor W. Adorno are taken up. Adorno on the subject of foreign words, in order to interpret Aufstellung under the concept of foreignness. Then, finally, a series of divergent reflections are proposed, that allow us to think Aufstellung’s critique of nationalism anachronistically and beyond German borders.

Design method of optical detection systems based on transimpedance amplifiers Vázquez, Patricia María Elena; Veiras, Francisco Ezequiel; Ciocci Brazzano, Ligia; Sorichetti, Patricio Aníbal Designing detection systems based on transimpedance amplifiers is a complex task because noise, frequency response, and stability are coupled constraints. This work presents a straightforward design method of detection systems based on transimpedance amplifiers. We take into account the objectives, scope of the design, and requirements and specifications, including the input signal levels. According to the small-signal model, the noise and stability are analyzed in detail. We present a systematic procedure to search for the acceptable values of the feedback network components based on these analyses. Then, we define a merit function to compare the performance of the acceptable combinations of feedback network components. For every acceptable combination, the function gives a quantitative measure of the degree of compliance for each design parameter: signal-to-noise ratio, highest operating frequency, and phase margin. As an example, we apply the method to optimize the design of an optical detection system using a PIN photodiode and a low-noise operational amplifier.

Un bypass a la administración pública: El caso del régimen de promoción industrial en argentina (1982- 1992); A bypass to the public administration: The case of the industrial promotion regime in Argentina (1982- 1992) Karamaneff, Luis Esteban Las políticas de desgravaciones y ventajas impositivas para la relocalización de empresas son una constante en todo el mundo como una forma de promover el desarrollo económico en territorios desfavorecidos. En el caso de Argentina se canalizaron mediante un régimen de promoción industrial regional que otorgó subsidios para relocalizar empresas en provincias económicamente deprimidas. Este artículo muestra cómo el gobierno de una provincia caracterizada como patrimonialista, San Luis, transformó su estructura productiva en un plazo de 10 años (1982-1992), al radicar una cantidad ingente de industrias en su territorio. Mediante la técnica de process tracing y una serie de entrevistas en profundidad se argumenta que el gobierno realizó una delegación informal de competencias burocráticas a un agente no institucionalizado, con la finalidad de que realice tareas que el aparato estatal no tenía capacidad de llevar a cabo y, de esa manera, promover la llegada de las inversiones a su territorio.; Tax relief policies and tax advantages for the relocation of companies are a constant throughout the world as a way of promoting economic development in disadvantaged territories. In the case of Argentina, they were channeled through a regional industrial promotion regime that granted subsidies to relocate companies in economically depressed provinces. This article shows how the government of a province characterized as patrimonialist, San Luis, transformed its productive structure in a period of 10 years (1982-1992), by locating a vast of industries in its territory. Using the process tracing technique and a series of in-depth interviews, it is argued that the government informally delegated bureaucratic competences to a non-institutionalized agent in order to perform tasks that the state apparatus did not have the capacity to carry out and, in this way, promote the arrival of investments in its territory

La interpelación del espejo: La Directora, una serie sobre la mercantilización y la diversidad en el capitalismo académico Muñiz Terra, Leticia Magali En este artículo se presenta una reflexión sobre la mercantilización de la educación universitaria y la diversidad de género y etnia en el sistema universitario de Estados Unidos. En particular se analiza críticamente la serie La Directora (netflix) mostrando las particularidades de la docencia y la educación individualista y neoliberal de los países desarrollados

Comparing Genomic Prediction Models by Means of Cross Validation Schrauf, Matías Florián; de los Campos, Gustavo; Munilla Leguizamon, Sebastian In the two decades of continuous development of genomic selection, a great variety of models have been proposed to make predictions from the information available in dense marker panels. Besides deciding which particular model to use, practitioners also need to make many minor choices for those parameters in the model which are not typically estimated by the data (so called “hyper-parameters”). When the focus is placed on predictions, most of these decisions are made in a direction sought to optimize predictive accuracy. Here we discuss and illustrate using publicly available crop datasets the use of cross validation to make many such decisions. In particular, we emphasize the importance of paired comparisons to achieve high power in the comparison between candidate models, as well as the need to define notions of relevance in the difference between their performances. Regarding the latter, we borrow the idea of equivalence margins from clinical research and introduce new statistical tests. We conclude that most hyper-parameters can be learnt from the data by either minimizing REML or by using weakly-informative priors, with good predictive results. In particular, the default options in a popular software are generally competitive with the optimal values. With regard to the performance assessments themselves, we conclude that the paired k-fold cross validation is a generally applicable and statistically powerful methodology to assess differences in model accuracies. Coupled with the definition of equivalence margins based on expected genetic gain, it becomes a useful tool for breeders.

Pensar el cine militante hoy: sobre la estética realista y la relación entre cine y política; Thinking militant cinema today: on realist aesthetics and the relationship between cinema and politics de la Puente, Maximiliano Ignacio Este artículo se propone reflexionar sobre las principales características que definen al cine militante argentino contemporáneo. Con este fin, se nutre de bibliografía especializada de autores que han abordado principalmente el videoactivismo surgido en los años noventa del siglo pasado en adelante, así como sus vínculos con el cine militante revolucionario de las décadas del sesenta y setenta. Más allá de las diferentes coyunturas, sostenemos que el cine militante es aquel que amplía el horizonte de posibilidades de lo visible y decible socialmente en una época determinada, a través de un objetivo contrainformativo, que pone en evidencia aquello que los medios masivos de comunicación hegemónicos se encargan de ocultar sistemáticamente. Abordamos también las posibilidades de una estética realista en torno a este tipo de producciones, y nos referimos a las tensiones que existen entre las preocupaciones formales y políticas en el marco del cine militante actual. Señalamos, finalmente, que la representación de los sectores populares subalternos, a los que este tipo de cine pretende alcanzar como público objetivo, implica una perspectiva que repone las complejidades éticas y estético/políticas de dar cuenta del otro.; This article sets out to reflect on the main characteristics that define contemporary Argentine militant cinema. To this end, it draws on the specialized bibliography of authors who have mainly dealt with the video activism that emerged in the 1990s and onwards, as well as its links with the revolutionary militant cinema of the 1960s and 1970s. Beyond the different conjunctures, we argue that militant cinema is that which broadens the horizon of possibilities of what is visible and socially decipherable in a given era, through a counter-informative objective, which brings to light what the hegemonic mass media systematically conceals. We also address the possibilities of a realist aesthetic in this type of production, and we refer to the tensions that exist between formal and political concerns in the framework of current militant cinema. Finally, we point out that the representation of the subaltern popular sectors, which this type of cinema aims to reach as a target audience, implies a perspective that replenishes the ethical and aesthetic/political complexities of accounting for the other.

Medios violentos y fiestas gauchas: el salto cinematográfico de Juan Moreira y el espíritu del Centenario; Violent Media and Gaucho Celebrations: The Cinematic Leap of Juan Moreira and the Spirit of the Centennial Suárez, Nicolás Este artículo aborda, en primer lugar, la relación entre las versiones circenses del Juan Moreira (1879-1880) de Gutiérrez y la llegada del cine a la Argentina, en tanto espectáculos que figuran la entrada en la modernidad como un salto. A partir de tal configuración, se postula que cada aparición de Moreira en el cine se articula sobre: un uso de la violencia como medio legítimo, un estado de la técnica cinematográfica y una idea de fiesta. Finalmente, tomando como estudio de caso la versión entrenada en el Centenario de 1910, se plantea que, al ser un éxito de público pero un intento fallido de hacer de Moreira un gaucho patriota, la película visibiliza las fisuras de un proyecto de nacionalización de masas que avanzaba por vías escurridizas, no controlables por las élites modernizadoras.; This paper examines, in the first place, the relationship between the circus versions of Gutiérrez’s Juan Moreira (1879-1880) and the arrival of cinema to Argentina, considered as shows that represent the entrance to modernity as a leap. Based on this configuration, secondly, we argue that every appearance of Moreira on screen is founded on: a use of violence as a legitimate medium, a state of the cinematographic technique, and an idea of celebration. Finally, taking the adaptation released during the 1910 Centennial as a case study, we affirm that, being a public success but a failed attempt to turn Moreira into a patriotic gaucho, the film makes visible the cracks in a project of nationalization of the masses that was moving along elusive paths, not entirely controlled by the modernizing elites.

Las violencias de género en Exactas: Resultados de la primera encuesta (2017-2019) y desafíos pendientes Dulbecco, Paloma; Mendiluce, Mauricio Javier; Lucaccini, Mirna; Quaglino, Ana La “Primera encuesta de percepción e incidencia sobre violencia de género y/o discriminación” fue lanzada en noviembre de 2017 y permaneció abierta hasta marzo de 2019. La iniciativa de la encuesta fue una de las primeras acciones públicas del Programa por la Igualdad de Género (=GenEx) de la Facultad de Ciencias Exactas y Naturales (FCEyN) de la Universidad de Buenos Aires (UBA), que fue creado en julio de 2016 y funciona, desde entonces, en el ámbito de la Secretaría de Extensión, Cultura Científica y Bienestar de la FCEyN.El trabajo de =GenEx puede sintetizarse en tres ejes: recibir e intervenir en consultas y denuncias conforme al “Protocolo de acción institucional para la prevención e intervención ante situaciones de violencia o discriminación de género u orientación sexual” de la UBA (en adelante, Protocolo); realizar actividades y campañas de concientización y prevención de las posibles violencias ejercidas en razón de diferencias de género, orientación sexual y expresión de género; y construir vínculos interinstitucionales al interior de la FCEyN y con otras facultades de la UBA y universidades nacionales para fortalecer su funcionamiento y las redes de trabajo.Para identificar la percepción e incidencia de la violencia de género en la comunidad, se elaboró una encuesta con preguntas en torno a distintas situaciones que son contempladas en el artículo 3º del Protocolo como acoso sexual, hechos con connotación sexista o hechos de violencia sexual. En caso de respuesta afirmativa a la pregunta sobre si se había vivido alguna de esas situaciones, se preguntó también sobre su frecuencia, el contexto en el cual sucedió, el género de la persona que actuó de manera violenta u ofensiva y el tipo de relación que existía entre las personas implicadas.

Response to clinical evaluation of the effectiveness of fusion-induced asymmetric transcription assay-based reverse transcription droplet digital PCR for ALK detection in formalin-fixed paraffin-embedded samples from lung cancer Peñaloza Coronas, Cynthia; Montilla Fonseca, Silvia Mariela; Sanchez, Mirna Lorena We value the work published by Dr Liu et al.1on the design and application of a fusion induced asymmetric transcription assay (FIATA)-based RT-ddPCR for the detection of ALK rearrangements in non-small cell lung cancer (NSCLC) samples. It is known that the actual gold standard method for the detection of gene rearrangements are FISH-based assays, and it is mainly because of the number of fusion variants for each marker, and the fact that it is not necessary for some genes to know the exact fusion product but to prove that the gene is rearranged, in order to provide target therapy that can counter the effects of these rearrangements. Given that the design of the probes is based on the fundamentals of a break-apart FISH assay, we agree that the protocol proposed in the article will represent an upgrade in contrast to the actual methods for the detection of ALK rearrangements and has the advantage of a quantitative set; thus, providing an invaluable tool in patient monitoring for disease progression.

Assessment of solar radiation data quality in typical meteorological years and its influence on the building performance simulation Bre, Facundo; e Silva Machado, Rayner M.; Linda Lawrie; Crawley, Drury B.; Lamberts, Roberto Solar radiation along with other weather variables are commonly processed on typical meteorological years (TMYs) to be applied in the design of various energy systems. However, in several regions of the world, solar radiation data usually lacks a suitable and/or representative measurement, which leads to its modeling and prediction to properly fill this information in the databases. Consequently, the accuracy of these models can influence the viability and proper design of such energy systems. Within this context, the present contribution aims to assess the quality of solar radiation data included in the most recent TMY databases with Brazilian data and how that quality can influence the selection of months that create TMYs as well as the building performance simulation (BPS) results. Because two different approaches to generate the solar radiation data are used, we evaluate the global horizontal irradiation data in the two latest versions of recent Brazilian TMY databases against the corresponding satellite-derived ones obtained from the POWER database (NASA). Simultaneously, as another alternative approach, global solar radiation data are calculated for the same studied locations and period through the modeling method used to generate the current version of the International Weather for Energy Calculations (IWEC2), and its performance is also compared against the corresponding reanalysis data (POWER). Finally, a set of case studies applying the local building performance regulations are exhaustively analyzed to quantify the impact of the uncertainty of solar radiation models on BPS results throughout Brazil. The results indicate that the accuracy of solar radiation models can highly influence the resulting TMY configurations. These changes can drive differences up to 40% on the prediction of the ideal annual loads of the residential buildings while, regardless of design performance, differences lower than 10% are found for the commercial case studies in most locations. Conversely, the prediction of peak loads for cooling shows to be more sensitive to the climate data changes in the commercial buildings than in the residential ones.

Heregulin Activity Assays for Residual Testing of Cell Therapy Products Monje, Paula; Bacallao, Ketty; Aparicio, Gabriela Inés; Lalwani, Anil Background: Heregulin is a ligand for the protooncogene product ErbB/HER that acts as a key mitogenic factor for human Schwann cells (hSCs). Heregulin is required for sustained hSC growth in vitro but must be thoroughly removed before cell collection for transplantation due to potential safety concerns. The goal of this study was to develop simple cell-based assays to assess the effectiveness of heregulin addition to and removal from aliquots of hSC culture medium. These bioassays were based on the capacity of a β1-heregulin peptide to elicit ErbB/HER receptor signaling in adherent ErbB2+/ErbB3+ cells. Results: Western blotting was used to measure the activity of three different β1-heregulin/ErbB-activated kinases (ErbB3/HER3, ERK/MAPK and Akt/PKB) using phospho-specific antibodies against key activating residues. The duration, dose-dependency and specificity of β1-heregulin-initiated kinase phosphorylation were investigated, and controls were implemented for assay optimization and reproducibility to detect β1-heregulin activity in the nanomolar range. Results from these assays showed that the culture medium from transplantable hSCs elicited no detectable activation of the aforementioned kinases in independent rounds of testing, indicating that the implemented measures can ensure that the final hSC product is devoid of bioactive β1-heregulin molecules prior to transplantation. Conclusions: These assays may be valuable to detect impurities such as undefined soluble factors or factors for which other biochemical or biological assays are not yet available. Our workflow can be modified as necessary to determine the presence of ErbB/HER, ERK, and Akt activators other than β1-heregulin using native samples, such as fresh isolates from cell- or tissue extracts in addition to culture medium.

Changes in the mechanical, micro-, and nano-structural properties of reinforced vulcanized natural rubber compounds: their dependence on the sio2/cb ratio Marzocca, Angel José; Rodriguez Garraza, Ana Lucia; Anbinder, Pablo Sebastián; Macchi, Carlos Eugenio; Somoza, Alberto Horacio A systematic study on the influence of fillers on the structural properties at micro and nanoscale of vulcanized compounds based on a natural rubber matrix reinforced with silica and/or carbon black is presented. Several compounds with different SiO2/CB ratios (1.5/1, 2.25/1, and 3/1) and total filler contents (55, 60, and 65 phr) were prepared and vulcanized at 150 °C. The experimental techniques used were rheometric, swelling and dynamic mechanical tests, and positron lifetime spectroscopy. From these techniques, cure reaction parameters, the fraction at the maximum degree of swelling, storage modulus, loss tangent, and fractional free volume were measured. Using a recent model based on a hydrodynamic description and the percolation of aggregates in a rubber matrix, it was found that regardless of the filler combinations, the dynamic storage modulus is well represented as a function of the filler volume fraction. Besides, beyond a critical SiO2/CB ratio (2.25/1) in the formulations of the compounds, the loss tangent does not depend on the SiO2/CB ratio. The results obtained show a direct correlation among mechanical properties, swelling and fractional free volume, and the type and amount of fillers in the reinforced compounds.

Mixed approach on Chroodactylon ornatum (Stylonematophyceae, Rhodophyta) tolerance to hyposalinity: growth, photosynthetic performance and carbohydrate analysis Daglio, Yasmin; Romero, Juan Manuel; Lagorio, María Gabriela; Stortz, Carlos Arturo; Rodriguez, Maria Cecilia Chroodactylon ornatum is a cosmopolitan non-Florideophycean red alga with a simple morphology, generally described as a euryhaline species. Herein, we compared the response of a marine strain under exposure to different salinities (3, 7.5, 15 and 30 psu) through the analyses of growth, morphology, chlorophyll a fluorescence, floridean starch properties, and mucilage composition. In 3 psu, the cultures consisted of solitary cells whereas the typical pseudofilamentous morphology of increasing length was found at higher salinities. The species grew in the whole range of salinities, although growth response together with photosynthetic efficiency were maximum in full seawater. The maximum relative electron transport rate (rETR) was significantly lower under hyposaline conditions, concomitant with the increase in photophysical decay but not in non-photochemical quenching of chlorophyll fluorescence (NPQ). Higher phycocyanin content at the highest salinity tested (30 psu) could be related to a more efficient energy transfer to the reaction centre. The amylopectin:amylose ratios were higher in 7.5 and 30 psu. Agarans extracted at different salinities showed similar sulphation degrees, but there was an increase in xylose content in the mucilage from lower salinities. This could be related to a change in physical properties of the sheath polysaccharide, yielding a polymer with lower gelling capacity which hampered the formation and/or elongation of pseudofilaments.

Case Report: Relevance of an Accurate Diagnosis and Monitoring of Infective Dermatitis Associated With Human T-Lymphotropic Virus Type 1 in Childhood Benencio, Paula; Ducasa, Nicolás; Arruvito, Maria Lourdes; Irurzun, Inés; Praino, Laura; Lamberti, Magdalena; Beraza, María; Berini, Carolina Andrea; Biglione, Mirna Marcela Human T-lymphotropic virus type 1 (HTLV-1) is a neglected retrovirus distributed worldwide and the ethiological agent of several pathologies, such as adult T-cell leukemia/lymphoma (ATLL), a chronic myelopathy known as HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) and infective dermatitis associated with HTLV-1 (IDH). HTLV-1 presents tropism for CD4+ T cells and induces deregulation of the cytokine profile. IDH is a severe, chronic superinfected eczema generally associated with Staphylococcus aureus and/or Streptococcus beta haemolyticus infection that responds partially to antibiotic therapy but prompt recurrence develops upon treatment withdrawal. IDH could be a risk factor for progression toward both HAM/TSP and ATLL and, similarly to other diseases associated with HTLV-1, it is sub-diagnosed particularly in non-endemic areas. Here, we present a case of IDH in a young boy living in Buenos Aires with symptoms since 2010, at the age of 5. HTLV-1 infection was suspected and confirmed in 2016. The patient exhibited chronic dermatosis with exudative eruption involving mainly the scalp, retroauricular regions, neck and abdomen. Clinical evaluations, routine laboratory tests, full blood count, and HTLV-1 diagnosis for this case are included.

Reduced non-Gaussianity by 30s rapid update in convective-scale numerical weather prediction Ruiz, Juan Jose; Lien, Guo-Yuan; Kondo, Keiichi; Otsuka, Shigenori; Miyoshi, Takemasa Non-Gaussian forecast error is a challenge for ensemble-based data assimilation (DA), particularly for more nonlinear convective dynamics. In this study, we investigate the degree of the non-Gaussianity of forecast error distributions at 1km resolution using a 1000-member ensemble Kalman filter, and how it is affected by the DA update frequency and observation number. Regional numerical weather prediction experiments are performed with the SCALE (Scalable Computing for Advanced Library and Environment) model and the LETKF (local ensemble transform Kalman filter) assimilating phased array radar observations every 30s. The results show that non-Gaussianity develops rapidly within convective clouds and is sensitive to the DA frequency and the number of assimilated observations. The non-Gaussianity is reduced by up to 40% when the assimilation window is shortened from 5min to 30s, particularly for vertical velocity and radar reflectivity.

Black holes with topological charges in Chern-Simons AdS5 supergravity Andrianopoli, Laura; Giribet, Gaston Enrique; López Díaz, Darío; Miskovic, Olivera We study static black hole solutions with locally spherical horizons coupled to non-Abelian field in N = 4 Chern-Simons AdS5 supergravity. They are governed by three parameters associated to the mass, axial torsion and amplitude of the internal soliton, and two ones to the gravitational hair. They describe geometries that can be a global AdS space, naked singularity or a (non-)extremal black hole. We analyze physical properties of two inequivalent asymptotically AdS solutions when the spatial section at radial infinity is either a 3-sphere or a projective 3-space. An important feature of these 3-parametric solutions is that they possess a topological structure including two SU(2) solitons that wind nontrivially around the black hole horizon, as characterized by the Pontryagin index. In the extremal black hole limit, the solitons’ strengths match and a soliton-antisoliton system unwinds. That limit admits both non-BPS and BPS configurations. For the latter, the pure gauge and non-pure gauge solutions preserve 1/2 and 1/16 of the original supersymmetries, respectively. In a general case, we compute conserved charges in Hamiltonian formalism, finding many similarities with standard supergravity black holes.

Palynology of a short sequence of the Lower Devonian Beartooth Butte Formation at Cottonwood Canyon (Wyoming): age, depositional environments and plant diversity Noetinger, Maria Sol; Bippus, Alexander C.; Tomescu, Alexander M. F. The Beartooth Butte Formation hosts the most extensive Early Devonian macroflora of western North America. The age of the flora at Cottonwood Canyon (Wyoming) has been constrained to the Lochkovian–Pragian interval, based on fish biostratigraphy and unpublished palynological data. We present a detailed palynological analysis of the plant-bearing layers at Cottonwood Canyon. The palynomorphs consist of 32 spore, five cryptospore, two prasinophycean algae and an acritarch species. The stratigraphic ranges of these palynomorphs indicate a late Lochkovian or Pragian age, confirming previous age assignments. Analysis of samples from three different depositional environments of the plant-bearing sequence (layers with in situ lycophyte populations, flood layers that buried those populations and an organic matter accumulation zone within a flood layer) demonstrate distinct palynofacies. Comparisons between palynomorph and plant macrofossil diversity reveal some discrepancies. Whereas zosterophylls and lycophytes, most diverse and abundant among the macrofossils, have only one known corresponding spore type (assignable to zosterophylls) in the palynomorph assemblage, the trimerophytes, rare in the macrofossil assemblage, are represented by three spore types. Some of these discrepancies reflect taphonomic differences between the macrofossils and palynomorphs, while others could be due to the fact that the parent plants of most palynomorph types in the Cottonwood Canyon assemblage are unknown. These observations emphasize the need for concerted efforts to bring together the knowledge of macro- and microfloras within Early Devonian localities. Nevertheless, given the palaeophytogeographic significance of the Beartooth Butte Formation flora, its palynofossil and macrofossil assemblages, taken together, provide new data relevant to future discussions of Early Devonian biogeography.

Elemental speciation analysis in environmental studies: Latest trends and ecological impact Llaver, Mauricio; Fiorentini Chirino, Emiliano Franco; Oviedo, Maria Natalia; Quintas, Pamela Yanina; Wuilloud, Rodolfo German Speciation analysis is a key aspect of modern analytical chemistry, as the toxicity, environmental mobility, and bioavailability of elemental analytes are known to depend strongly on an element’s chemical species. Henceforth, great efforts have been made in recent years to develop methods that allow not only the determination of elements as a whole, but also each of its separate species. Environmental analytical chemistry has not ignored this trend, and this review aims to summarize the latest methods and techniques developed with this purpose. From the perspective of each relevant element and highlighting the importance of their speciation analysis, different sample treatment methods are introduced and described, with the spotlight on the use of modern nanomaterials and novel solvents in solid phase and liquid-liquid microextractions. In addition, an in-depth discussion of instrumental techniques aimed both at the separation and quantification of metal and metalloid species is presented, ranging from chromatographic separations to electrochemical speciation analysis. Special emphasis is made throughout this work on the greenness of these developments, considering their alignment with the precepts of the Green Chemistry concept and critically reviewing their environmental impact.

La muerte acecha en mares grises: experiencias del cruce marítimo entre Argentina y Europa durante la primera guerra mundial; Death lurks in grey seas: Experiences of the maritime crossing between Argentina and Europe during the First World War Desiderato, Agustín Daniel In recent years, the repercussions of the First World War in Latin America have received increasing attention in the academic literature. However, the impact of the war at sea on the continent has not been exhaustively investigated. With the belligerents fighting for control of overseas communication and trade routes, passengers and sailors embarked on ocean liners and cargo ships to travel between South America and Europe. This article explores and analyses the experiences of those who crossed the Atlantic to and from the Argentine Republic. In so doing, it adds a Latin American dimension to the knowledge and understanding of the 1914-18 naval war.; En los últimos años, las repercusiones de la Primera Guerra Mundial en América Latina han recibió una atención creciente en la literatura académica. Sin embargo, el impacto de la guerra en el mar en el continente no ha sido investigada exhaustivamente. Con los beligerantes luchando por el control de las rutas comerciales y de comunicación en el exterior, los pasajeros y marineros se embarcaron en transatlánticos y buques de carga para viajar entre Sudamérica y Europa. Este artículo explora y analiza las experiencias de los que cruzaron el Atlántico hacia y desde la República Argentina. Al hacerlo, añade una dimensión latinoamericana al conocimiento y comprensión de la 1914-18 guerra naval.