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Zooplanktonic copepods represent a major biological mass in the marine food chain that can be affected by climate change. Monitoring the health of this critical biomass is essential for increasing our understanding of the impact of environmental changes on marine environments. Since the lipidomes of marine organisms are known to adapt to alterations in pH, temperature, and availability of metabolic precursors, lipidomics is one technology that can be used for monitoring copepod adaptations. Among the key lipid parameters that can be monitored are the fatty acid substituents of glycerolipids and glycerophospholipids. We utilized high-resolution tandem mass spectrometry (≤2 ppm mass error) to characterize the fatty acid substituents of triacylglycerols, glycerophosphocholines, ceramides, and sphingomyelins of Labidocerca aestiva. This included monitoring for furan fatty acid substituents, a family of fatty acids unique to marine organisms. These data will contribute to establishing a lipid database of the fatty acid substituents of essential structural lipids. The key findings were that polyunsaturated fatty acids (PUFAs) were only major substituents in glycerophosphocholines with 36 to 44 carbons. Triacylglycerols, ceramides, and sphingomyelins contained minimal PUFA substituents. Furan fatty acids were limited to mono- and di-acylglycerols. In summary, we have built a baseline database of the fatty acid substituents of key structural lipids in Labidocerca aestiva. With this database, we will next evaluate potential seasonal changes in these lipid substituents and long-term effects of climate change. [ABSTRACT FROM AUTHOR]

Fast radio bursts (FRBs) are high-energy, short-duration phenomena in radio astronomy. Identifying their host galaxies can provide insights into their mysterious origins. In this paper, we introduce a novel approach to identifying potential host galaxies in three-dimensional space. We use FRB 20190425A and GW190425 as examples to illustrate our method. Recently, due to spatial and temporal proximity, the potential association of GW190425 with FRB 20190425A has drawn attention, leading to the identification of a likely host galaxy, UGC 10667, albeit without confirmed kilonova emissions. We search for the host galaxy of FRB 20190425A with a full CHIME localization map. Regardless of the validity of the association between GW190425 and FRB 20190425A, we identify an additional potential host galaxy (SDSS J171046.84+212732.9) from the updated GLADE galaxy catalog, supplementing the importance of exploring the new volume. We employed various methodologies to determine the most probable host galaxy of GW190424 and FRB 20190425A, including a comparison of galaxy properties and constraints on their reported observation limits using various kilonova models. Our analysis suggests that current observations do not definitively identify the true host galaxy. Additionally, the kilonova models characterized by a gradual approach to their peak are contradicted by the observational upper limits of both galaxies. Although the absence of optical emission detection raises doubts, it does not definitively disprove the connection between the gravitational wave (GW) and FRB. [ABSTRACT FROM AUTHOR]

In the emerging era of big data astrophysics, large-scale extragalactic surveys will soon provide high-quality imaging for billions of celestial objects to answer major questions in astrophysics such as the nature of dark matter and dark energy. Precision cosmology with surveys requires accurate photometric redshift (photo- z) estimation with well-constrained uncertainties as inputs for weak lensing models to measure cosmological parameters. Machine learning methods have shown promise in optimizing the information gained from galaxy images in photo- z estimation; however, many of these methods are limited in their ability to estimate accurate uncertainties. In this work, we present one of the first applications of Bayesian convolutional neural networks (BCNNs) for photo- z estimation and uncertainties. In addition, we use conformal mapping to calibrate the photo- z uncertainties to achieve good statistical coverage. We use the public GalaxiesML data set of ∼300k galaxies from the Hyper Suprime-Cam survey containing five-band photometric images and known spectroscopic redshifts from 0 < z < 4. We find that the performance is much improved when using images compared to photometry, with the BCNN achieving 0.098 rms error, a standard outlier rate of 3.9%, a 3 σ outlier rate of 4.5%, and a bias of 0.0007. The performance drops significantly beyond z > 1.5 due to the relative lack of training data beyond those redshifts. This investigation demonstrates the power of using images directly and we advocate that future photo- z analysis of large-scale surveys include galaxy images. [ABSTRACT FROM AUTHOR]

We present an atmospheric retrieval analysis of the Y0 brown dwarf WISE J035934.06−540154.6 using the low-resolution 0.96–12 μ m James Webb Space Telescope (JWST) spectrum presented in Beiler et al. We obtain volume number mixing ratios of the major gas-phase absorbers (H2O, CH4, CO, CO2, PH3, and H2S) that are three to five times more precise than previous work that used Hubble Space Telescope (HST) spectra. We also find an order-of-magnitude improvement in the precision of the retrieved thermal profile, a direct result of the broad wavelength coverage of the JWST data. We used the retrieved thermal profile and surface gravity to generate a grid of chemical forward models with varying metallicity, (C/O)atm, and strengths of vertical mixing as encapsulated by the eddy diffusion coefficient K zz. Comparison of the retrieved abundances with this grid of models suggests that the deep atmosphere of WISE 0359−54 shows signs of vigorous vertical mixing with K zz = 109 [cm2 s−1]. To test the sensitivity of these results to our five-knot spline thermal profile model, we performed a second retrieval using the Madhusudhan & Seager thermal profile model. While the results of the two retrievals generally agree well, we do find differences between the retrieved values of mass and volume number mixing ratio of H2S with fractional differences of the median values of −0.64 and −0.10, respectively. In addition, the five-knot thermal profile is consistently warmer at pressure between 1 and 70 bar. Nevertheless, our results underscore the power that the broad-wavelength infrared spectra obtainable with the JWST have to characterize the atmospheres of cool brown dwarfs. [ABSTRACT FROM AUTHOR]

Many accretion-powered pulsars rotate in magnetocentrifugal disequilibrium, spinning up or down secularly over multiyear intervals. The magnetic dipole moment μ of such systems cannot be inferred uniquely from the time-averaged aperiodic X-ray flux 〈 L (t)〉 and pulse period 〈 P (t)〉, because the radiative efficiency of the accretion is unknown and degenerate with the mass accretion rate. Here, we circumvent the degeneracy by tracking the fluctuations in the unaveraged time series L (t) and P (t) using an unscented Kalman filter, whereupon μ can be estimated uniquely, up to the uncertainties in the mass, radius, and distance of the star. The analysis is performed on Rossi X-ray Timing Explorer observations for 24 X-ray transients in the Small Magellanic Cloud, which have been monitored regularly for ∼16 yr. As well as independent estimates of μ, the analysis yields time-resolved histories of the mass accretion rate and the Maxwell stress at the disk–magnetosphere boundary for each star, and hence auto- and cross-correlations involving the latter two state variables. The inferred fluctuation statistics convey important information about the complex accretion physics at the disk–magnetosphere boundary. [ABSTRACT FROM AUTHOR]

En este trabajo se aborda el estudio artístico de la Cabalgata alegórica en el marco de la Sevilla industrial y lúdica de 1900.

Analyses of pulsar timing data have provided evidence for a stochastic gravitational wave background in the nanohertz frequency band. The most plausible source of this background is the superposition of signals from millions of supermassive black hole binaries. The standard statistical techniques used to search for this background and assess its significance make several simplifying assumptions, namely (i) Gaussianity, (ii) isotropy, and most often, (iii) a power-law spectrum. However, a stochastic background from a finite collection of binaries does not exactly satisfy any of these assumptions. To understand the effect of these assumptions, we test standard analysis techniques on a large collection of realistic simulated data sets. The data-set length, observing schedule, and noise levels were chosen to emulate the NANOGrav 15 yr data set. Simulated signals from millions of binaries drawn from models based on the Illustris cosmological hydrodynamical simulation were added to the data. We find that the standard statistical methods perform remarkably well on these simulated data sets, even though their fundamental assumptions are not strictly met. They are able to achieve a confident detection of the background. However, even for a fixed set of astrophysical parameters, different realizations of the universe result in a large variance in the significance and recovered parameters of the background. We also find that the presence of loud individual binaries can bias the spectral recovery of the background if we do not account for them. [ABSTRACT FROM AUTHOR]

Tendo como pano de fundo o texto "Varandas" (presente na obra "Infância Berlinense: 1900), o presente artigo teve por objetivo refletir sobre a noção de autor na obra benjaminiana a partir de alguns dos seus textos que tratam da temática ("Experiência e pobreza", "O autor como produtor" e "O narrador: considerações sobre a obra de Nikolai Leskov"). Assim, pôde-se observar que o relato "autobiográfico" de Benjamin se encontra amparado, em um primeiro momento, no conceito de "rememoração". Desta maneira, ao tratar de sua infância burguesa na cidade de Berlim, Benjamin procura, na verdade, trazer à tona elementos para pensar criticamente a realidade social do momento presente, especialmente no que diz respeito ao avanço da técnica, do desencantamento do mundo e da desigualdade de classes no capitalismo. Neste sentido, Benjamin apresenta o autor como aquele que tem duas faces principais: (a) aquela que insere a sua experiência no texto narrativo; e (b) aquela que insere seu posicionamento político aliada a uma preocupação acerca da qualidade do texto literário.

Quantifying the connection between galaxies and their host dark matter halos has been key for testing cosmological models on various scales. Below M ⋆ ∼ 109 M ⊙, such studies have primarily relied on the satellite galaxy population orbiting the Milky Way (MW). Here we present new constraints on the connection between satellite galaxies and their host dark matter subhalos using the largest sample of satellite galaxies in the Local Volume (D ≲ 12 Mpc) to date. We use 250 confirmed and 71 candidate dwarf satellites around 27 MW-like hosts from the Exploration of Local VolumE Satellites (ELVES) Survey and use the semianalytical SatGen model for predicting the population of dark matter subhalos expected in the same volume. Through a Bayesian model comparison of the observed and the forward-modeled satellite stellar mass functions (SSMFs), we infer the satellite stellar-to-halo mass relation. We find that the observed SSMF is best reproduced when subhalos at the low-mass end are populated by a relation of the form M ⋆ ∝ M peak α , with a moderate slope of α const = 2.10 ± 0.01 and a low scatter, constant as a function of the peak halo mass, of σ const = 0.06 − 0.05 + 0.07 . A model with a steeper slope (α grow = 2.39 ± 0.06) and a scatter that grows with decreasing M peak is also consistent with the observed SSMF but is not required. Our new model for the satellite–subhalo connection, based on hundreds of Local Volume satellite galaxies, is in line with what was previously derived using only MW satellites. [ABSTRACT FROM AUTHOR]

Several features in the mass spectrum of merging binary black holes (BBHs) have been identified using data from the Third Gravitational Wave Transient Catalog (GWTC-3). These features are of particular interest as they may encode the uncertain mechanism of BBH formation. We assess if the features are statistically significant or the result of Poisson noise due to the finite number of observed events. We simulate catalogs of BBHs whose underlying distribution does not have the features of interest, apply the analysis previously performed on GWTC-3, and determine how often such features are spuriously found. We find that one of the features found in GWTC-3, the peak at ∼35 M ☉, cannot be explained by Poisson noise alone: peaks as significant occur in 1.7% of catalogs generated from a featureless population. This peak is therefore likely to be of astrophysical origin. The data is suggestive of an additional significant peak at ∼10 M ☉, though the exact location of this feature is not resolvable with current observations. Additional structure beyond a power law, such as the purported dip at ∼14 M ☉, can be explained by Poisson noise. We also provide a publicly available package, GWMockCat, that creates simulated catalogs of BBH events with correlated measurement uncertainty and selection effects according to user-specified underlying distributions and detector sensitivities. [ABSTRACT FROM AUTHOR]

Galaxy stellar mass is known to be monotonically related to the size of the galaxy's globular cluster (GC) population for Milky Way sized and larger galaxies. However, the relation becomes ambiguous for dwarf galaxies, where there is some evidence for a downturn in GC population size at low galaxy masses. Smaller dwarfs are increasingly likely to have no GCs, and these zeros cannot be easily incorporated into linear models. We introduce the Hierarchical Errors-in-variables ERrors-in-variables BAyesian Lognormal hurdle (HERBAL) model to represent the relationship between dwarf galaxies and their GC populations, and apply it to the sample of Local Group galaxies, where the luminosity range coverage is maximal. This bimodal model accurately represents the two populations of dwarf galaxies: those that have GCs and those that do not. Our model thoroughly accounts for all uncertainties, including measurement uncertainty, uncertainty in luminosity to stellar mass conversions, and intrinsic scatter. The hierarchical nature of our Bayesian model also allows us to estimate galaxy masses and individual mass-to-light ratios from luminosity data within the model. We find that 50% of galaxies are expected to host GC populations at a stellar mass of log 10 (M *) = 6.996 , and that the expected mass of GC populations remains linear down to the smallest galaxies. Our hierarchical model recovers an accurate estimate of the Milky Way stellar mass. Under our assumed error model, we find a nonzero intrinsic scatter of 0.59 − 0.21 + 0.3 (95% credible interval) that should be accounted for in future models. [ABSTRACT FROM AUTHOR]

Young supernova remnant (SNR) shocks are believed to be the main sites of galactic cosmic-ray production, showing X-ray synchrotron-dominated spectra in the vicinity of their shock. While a faint thermal signature left by the shocked interstellar medium (ISM) should also be found in the spectra, proofs for such an emission in Tycho's SNR have been lacking. We perform an extended statistical analysis of the X-ray spectra of five regions behind the blast wave of Tycho's SNR using Chandra archival data. We use Bayesian inference to perform extended parameter space exploration and sample the posterior distributions of a variety of models of interest. According to Bayes factors, spectra of all five regions of analysis are best described by composite three-component models taking nonthermal emission, ejecta emission, and shocked ISM emission into account. The shocked ISM stands out the most in the northern limb of the SNR. We find for the shocked ISM a mean electron temperature kT e = 0.96 − 0.51 + 1.33 keV for all regions and a mean ionization timescale n e t = 2.55 − 1.22 + 0.5 × 10 9 cm−3 s resulting in a mean ambient density n e = 0.32 − 0.15 + 0.23 cm−3 around the remnant. We performed an extended analysis of the northern limb and show that the measured synchrotron cutoff energy is not well constrained in the presence of a shocked ISM component. Such results cannot currently be further investigated by analyzing emission lines in the 0.5–1 keV range, because of the low Chandra spectral resolution in this band. We show with simulated spectra that Athena X-ray Integral Field Unit future performances will be crucial to address this point. [ABSTRACT FROM AUTHOR]

Cosmological parameters encoding our understanding of the expansion history of the universe can be constrained by the accurate estimation of time delays arising in gravitationally lensed systems. We propose TD-CARMA, a Bayesian method to estimate cosmological time delays by modeling observed and irregularly sampled light curves as realizations of a continuous auto-regressive moving average (CARMA) process. Our model accounts for heteroskedastic measurement errors and microlensing, an additional source of independent extrinsic long-term variability in the source brightness. The semiseparable structure of the CARMA covariance matrix allows for fast and scalable likelihood computation using Gaussian process modeling. We obtain a sample from the joint posterior distribution of the model parameters using a nested sampling approach. This allows for "painless" Bayesian computation, dealing with the expected multimodality of the posterior distribution in a straightforward manner and not requiring the specification of starting values or an initial guess for the time delay, unlike existing methods. In addition, the proposed sampling procedure automatically evaluates the Bayesian evidence, allowing us to perform principled Bayesian model selection. TD-CARMA is parsimonious, and typically includes no more than a dozen unknown parameters. We apply TD-CARMA to six doubly lensed quasars HS2209+1914, SDSS J1001+5027, SDSS J1206+4332, SDSS J1515+1511, SDSS J1455+1447, and SDSS J1349+1227, estimating their time delays as −21.96 ± 1.448, 120.93 ± 1.015, 111.51 ± 1.452, 210.80 ± 2.18, 45.36 ± 1.93, and 432.05 ± 1.950, respectively. These estimates are consistent with those derived in the relevant literature, but are typically two to four times more precise. [ABSTRACT FROM AUTHOR]

We have investigated the systematic differences introduced when performing a Bayesian-inference analysis of the equation of state (EOS) of neutron stars employing either variable- or constant-likelihood functions. The former has the advantage of retaining the full information on the distributions of the measurements, making exhaustive usage of the data. The latter, on the other hand, has the advantage of a much simpler implementation and reduced computational costs. In both approaches, the EOSs have identical priors and have been built using the sound speed parameterization method so as to satisfy the constraints from X-ray and gravitational waves observations, as well as those from chiral effective theory and perturbative quantum chromodynamics. In all cases, the two approaches lead to very similar results and the 90% confidence levels essentially overlap. Some differences do appear, but in regions where the probability density is extremely small and are mostly due to the sharp cutoff on the binary tidal deformability Λ ˜ ≤ 720 set in the constant-likelihood approach. Our analysis has also produced two additional results. First, an inverse correlation between the normalized central number density, n c,TOV/ n s , and the radius of a maximally massive star, R TOV. Second, and most importantly, it has confirmed the relation between the chirp mass and the binary tidal deformability. The importance of this result is that it relates  chirp , which is measured very accurately, and Λ ˜ , which contains important information on the EOS. Hence, when  chirp is measured in future detections, our relation can be used to set tight constraints on Λ ˜ . [ABSTRACT FROM AUTHOR]

We combine data sets from the CGM2 and CASBaH surveys to model a transition point, R cross, between circumgalactic and intergalactic media (CGM and IGM, respectively). In total, our data consist of 7244 galaxies at z < 0.5 with precisely measured spectroscopic redshifts, all having impact parameters of 0.01–20 comoving Mpc from 28 QSO sightlines with high-resolution UV spectra that cover H i Ly α. Our best-fitting model is a two-component model that combines a 3D absorber–galaxy cross-correlation function with a simple Gaussian profile at inner radii to represent the CGM. By design, this model gives rise to a determination of R cross as a function of galaxy stellar mass, which can be interpreted as the boundary between the CGM and IGM. For galaxies with 108 ≤ M ⋆/ M ⊙ ≤ 1010.5, we find that R cross(M ⋆) ≈ 2.0 ± 0.6 R vir. Additionally, we find excellent agreement between R cross(M ⋆) and the theoretically determined splashback radius for galaxies in this mass range. Overall, our results favor models of galaxy evolution at z < 0.5 that distribute T ≈ 104K gas to distances beyond the virial radius. [ABSTRACT FROM AUTHOR]

Dark sirens, i.e., gravitational-wave (GW) sources without electromagnetic counterparts, are new probes of the expansion of the universe. The efficacy of this method relies on correctly localizing the host galaxies. However, recent theoretical studies have shown that astrophysical environments could mislead the spatial localization by distorting the GW signals. It is unclear whether and to what degree the incorrect spatial localizations of dark sirens would impair the accuracy of the measurement of the cosmological parameters. To address this issue, we consider the future observations of dark sirens using the Cosmic Explorer and the Einstein Telescope, and we design a Bayesian framework to access the precision of measuring the Hubble–Lemaître constant H 0. Interestingly, we find that the precision is not compromised when the number of well-localized dark sirens is significantly below 300, even in the extreme scenario that all the dark sirens are localized incorrectly. As the number exceeds 300, the incorrect spatial localizations start to produce statistically noticeable effects, such as a slow convergence of the posterior distribution of H 0. We propose several tests that can be used in future observations to verify the spatial localizations of dark sirens. Simulations of these tests suggest that incorrect spatial localizations will dominate a systematic error of H 0 if as much as 10% of a sample of 300 well-localized dark sirens are affected by their environments. Our results have important implications for the long-term goal of measuring H 0 to a precision of <1% using dark sirens. [ABSTRACT FROM AUTHOR]

New analyses of gravitational-wave events raise questions about the nature of some events. For example, LIGO–Virgo–KAGRA initially determined GW151226 to be a merger with a mass ratio q ≈ 0.5 and effective inspiral spin χ eff ≈ 0.2. However, recent works offer an alternative picture: GW151226 is a lower mass ratio event q ≈ 0.3 with slightly higher spin χ eff ≈ 0.3. This discrepancy has been challenging to resolve, as a wide range of differences are employed for each analysis. This work introduces a "deep follow-up" framework to efficiently compute the posterior odds between two different peaks in parameter space. In doing so, we aim to help resolve disputes about the true nature of gravitational-wave events associated with conflicting astrophysical interpretations. Our proposal is not a replacement for standard inference techniques; instead, our method provides a diagnostic tool to understand discrepancies between conflicting results. We demonstrate this method by studying three q–χ eff peaks proposed for GW151226. We find that the (q ∼ 0.5, χ eff ∼ 0.2) interpretation is only slightly preferred over the (q ∼ 0.3, χ eff ∼ 0.3) hypothesis with posterior odds of ∼1.7 ± 0.4, suggesting that neither of the two peaks can be ruled out. We discuss strategies to produce more reliable parameter estimation studies in gravitational-wave astronomy. [ABSTRACT FROM AUTHOR]

Current research indicates that (sub)surface ocean worlds essentially devoid of subaerial landmasses (e.g., continents) are common in the Milky Way and that these worlds could host habitable conditions, thence raising the possibility that life and technological intelligence (TI) may arise in such aquatic settings. It is known, however, that TI on Earth (i.e., humans) arose on land. Motivated by these considerations, we present a Bayesian framework to assess the prospects for the emergence of TIs in land- and ocean-based habitats (LBHs and OBHs). If all factors are equally conducive for TIs to arise in LBHs and OBHs, we demonstrate that the evolution of TIs in LBHs (which includes humans) might have very low odds of roughly 1 in 103 to 1 in 104, thus outwardly contradicting the Copernican principle. Hence, we elucidate three avenues whereby the Copernican principle can be preserved: (i) the emergence rate of TIs is much lower in OBHs, (ii) the habitability interval for TIs is much shorter in OBHs, and (iii) only a small fraction of worlds with OBHs comprise appropriate conditions for effectuating TIs. We also briefly discuss methods for empirically falsifying our predictions and comment on the feasibility of supporting TIs in aerial environments. [ABSTRACT FROM AUTHOR]

The detection of gravitational waves from the binary neuron star merger GW170817 and electromagnetic counterparts GRB170817A and AT2017gfo kick-started the field of gravitational-wave multimessenger astronomy. The optically red to near-infrared emission ("red" component) of AT2017gfo was readily explained as produced by the decay of newly created nuclei produced by rapid neutron capture (a kilonova). However, the ultraviolet to optically blue emission ("blue" component) that was dominant at early times (up to 1.5 days) received no consensus regarding its driving physics. Among many explanations, two leading contenders are kilonova radiation from a lanthanide-poor ejecta component and shock interaction (cocoon emission). In this work, we simulate AT2017gfo-like light curves and perform a Bayesian analysis to study whether an ultraviolet satellite capable of rapid gravitational-wave follow-up, could distinguish between physical processes driving the early "blue" component. We find that ultraviolet data starting at 1.2 hr distinguishes the two early radiation models up to 160 Mpc, implying that an ultraviolet mission like Dorado would significantly contribute to insights into the driving emission physics of the postmerger system. While the same ultraviolet data and optical data starting at 12 hr have limited ability to constrain model parameters separately, the combination of the two unlocks tight constraints for all but one parameter of the kilonova model up to 160 Mpc. We further find that a Dorado-like ultraviolet satellite can distinguish the early radiation models up to at least 130 (60) Mpc if data collection starts within 3.2 (5.2) hr for AT2017gfo-like light curves. [ABSTRACT FROM AUTHOR]

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A finales del siglo XIX, la fotografía de paisaje en Colombia contribuyó a crear las primeras imágenes de la región. La manera de representar el espacio, comparado con técnicas pictóricas, implicó la creación de una imagen que reconociera una unidad visual. En la presente investigación se analizaron cerca de 800 fotografías de diversos acopios documentales que permitieron interpretar cómo, mediante el desarrollo de estas imágenes y de su popularización a través de medios como la tarjeta postal, se impulsó el desarrollo de emblemas simbólicos del paisaje. Siguiendo de cerca la idea de unidad desde el pensamiento de Georg Simmel, profundizando a través de la noción de cliché de Gilles Deleuze en su seminario sobre pintura, y tomando el mismo concepto desde la obra de la lingüista Ruth Amossy, analizaremos cómo en Colombia, por medio de las adaptaciones visuales de la fotografía, el paisaje adquirió la forma visual que le permitió transformar un lugar en un ícono.

Through the lenses of urban planning, consumerism, and print and visual culture, this paper explores Theodore Dreiser’s unsettled vision of the fin de siècle American metropolis as expressed in Sister Carrie (1900). The novel’s troubling discrepancy between the appearance and true nature of things calls into question the apparent success achieved by the title character and envisioned by others. To tease out the implications of this discrepancy, it is important to consider the novel’s representations of windows and newspapers—the media of modern perception through which the novel’s protagonists, Carrie Meeber and G.W. Hurstwood, view the city. Acts of window-gazing and newspaper-reading trigger idealized images of life that challenge each character to transform his or her fantasy into reality. Yet, whether in the workplace, the home, or the streets, successfully bridging the two ultimately remains illusory.

At the beginning of the twentieth century, many Latin-Americans traveled to Paris. Settled there or in transit, they sought an education and an artistic life difficult to achieve in their countries of origin. Individual or collective visits to "lighthouse artists" constituted an important part of their sociability and bohemia. The sculptor Auguste Rodin was among the best incarnations of the ideals of the modern "genius". After his big exhibition of 1900, a commercial success and its launching in the international arena, its workshop in Meudon and its Parisian residence became must-sees for every intellectual or artist in Paris. This article analyzes the traces that the workshop and the figure of the sculptor left in the Latin American artists and intellectuals who knew him in Paris. His figure had big relevance for a generation of artists responsible for the introduction of modernism in their native countries. The exchanges, product of these encounters, and the texts of those who expressed their passionate impressions about him are examples of an early moment of internationalization of modern sculpture.

Caras y Caretas, una de las publicaciones argentinas de mayor éxito hacia 1900, se identificó plenamente con los rasgos emergentes de la ciudad capital, afectada por un flujo inmigratorio sin precedentes y por los cambios de una modernización acelerada. El carácter heterogéneo y la lógica mercantil eran rasgos que la revista compartía con Buenos Aires. Ambas convocaban a la multitud heterogénea, y eran lugares de cruce y mezcla. Lo misceláneo, presente en la configuración formal y temática de la revista, coincidía con la presencia y circulación aleatoria de personas, objetos y mercancías en la urbe. Allí, como en la revista, se discutían los hábitos cerrados y tradicionales, mostrando el dinamismo de una sociedad (y una cultura) que cuestionaba los elementos restrictivos y liberaba las mercancías. En este marco, se exploran ciertas imágenes de la ciudad (el mercado, la calle, el balcón) que ayudan a comprender cómo la revista se representaba a sí misma en el espacio urbano.

Using a broad notion of materialities, the article touches upon some aspects of Viennese modernity with the aim of highlighting several dimensions of the practice of writing that offer relevant parallels to the work of Fernando Pessoa.