Misleading Discourse on Instagram : a Multimodal Study of Latin American Presidential Candidates in the Face of COVID-19

Instagram as a multimodal information network has helped politicians to position both their brand and their campaign. We analyzed whether the images and texts published during the pandemic contained misinformation. We studied from a multimodal perspective the Instagram accounts of the presidential candidates of four Latin American countries which held elections in 2021 to identify how much of the discourse was related to controlling the pandemic. The discourse was analyzed using different taxonomies. In the correlation between the discourse and following the recommendations of the World Health Organization (WHO), Chile stood out with the highest level of pandemic compliance; Peru and Ecuador were placed in the middle, while Honduras showed little if any interest. The conclusion was that politicians focused primarily on their campaigns and marginally on the pandemic. The omission of COVID-19 from most publications reflected a misinformative discourse which could potentially confuse the public.Instagram com a xarxa multimodal ajuda els polítics a posicionar la seva marca i campanya. Analitzem si existeix informació errònia en les imatges i textos publicats en plena pandèmia. S'estudien les publicacions a Instagram dels candidats presidencials de 4 països llatinoamericans amb eleccions el 2021 i es pretén identificar quant del discurs està relacionat amb la prevenció davant la pandèmia des d'una perspectiva multimodal. S'analitza el discurs a través de diferents taxonomies. En la correlació entre el discurs i el seguiment de les recomanacions de l'OMS destaca Xile amb el seguiment més gran, el Perú i l'Equador queden en un terme mitjà, i Hondures no desprèn cap interès. Es conclou que els polítics se centren en la seva campanya i molt poc en la pandèmia. L'omissió de la COVID-19 en la majoria de les publicacions projecta un discurs amb informació errònia que pot confondre la ciutadania.Instagram como red multimodal ayuda a los políticos a posicionar su marca y campaña. Analizamos si existe información errónea en las imágenes y textos publicados en plena pandemia. Se estudian las publicaciones en Instagram de los candidatos presidenciales de 4 países latinoamericanos con elecciones en 2021 y se pretende identificar cuánto del discurso está relacionado con la prevención frente a la pandemia desde una perspectiva multimodal. Se analiza el discurso a través de diferentes taxonomías. En la correlación entre el discurso y el seguimiento de las recomendaciones de la OMS destaca Chile con mayor seguimiento, Perú y Ecuador quedan en un término medio, y Honduras desprende interés nulo. Se concluye que los políticos se centran en su campaña y muy poco en la pandemia. La omisión de la COVID-19 en la mayoría de las publicaciones proyecta un discurso con información errónea que puede confundir a la ciudadanía

Soil Water Movement in a Watershed in the Chilean Patagonia

Magallanes region, located southern Chile, contains about 1.9 million sheep heads, in about 5 million hectares of rangelands. However, forage production is concentrated in small wetlands meadows called locally “Vegas” that only represent about 300.000 hectares. Those ecosystems that sustain patagonian ranches, produce 20 times more forage biomass than the surrounding natural rangelands. Patagonian vegas have concave topography with a hydrophyte (wet) center, and mesic slopes and xeric highlands of Festuca gracillima. Although the moisture content is controled by topography, there is scarce information about the movement of water through this concave topography. Also, the spatial variability of the soil between the Xeric to the Hydrophyte parts must be taking in account. It is essential to evaluate the movement of water inside the soil, to define agronomic managements to promote the storage and conduction of water. The study was conducted in a watershed dominated by vegas at the Kampenaike Experimental Station in Magallanes region, in Chilean Patagonia (-52,7 ° Lat.; -70.97° Long). Soil was monitored by instruments in five pits, two at East and West of Xeric side; two at East and West of mesic side; and the last at the middle of the vega. Soil moisture sensors (n = 2) and water tension (n = 1) were placed in three soil horizons (5, 30 and 80 cm deep). A weather station was set up in the middle of the vega. Differences in the physical properties that govern the storage and conduction of water between all the sectors were founded. The differences were due to the great spatial variability of the type of soil, because the topography and the genesis

AGN-Host Galaxy Connection: Morphology and Colours of X-ray Selected AGN at z < 2

The connection between AGN and their host galaxies has been widely studied over recent years, showing it to be of great importance for providing answers to some fundamental questions related with AGN fueling mechanisms, their formation and evolution. Using X-ray and one of the deepest broad-band optical data sets, we studied morphology and colours in relationship with X-ray properties for sources at redshifts z < 2.0, using a sample of 262 AGN in the Subaru/XMM-Newton Deep Survey (SXDS). Morphological classification was obtained using the galSVM code, one of the new methods useful especially when dealing with high-redshift sources and low-resolution data. Colour-magnitude diagrams were studied in relationship with redshift, morphology, X-ray obscuration, and X-ray-to-optical flux ratio. Finally, the significance of different regions was analysed on colour-magnitude diagrams, relating the observed properties of AGN populations with some models of their formation and evolution.Comment: 24 pages, 19 figures, accepted for publication in Astronomy&Astrophysic

Are luminous radio-loud active galactic nuclei triggered by galaxy interactions?

We present the results of a comparison between the optical morphologies of a complete sample of 46 southern 2Jy radio galaxies at intermediate redshifts (0.05<z<0.7) and those of two control samples of quiescent early-type galaxies: 55 ellipticals at redshifts z<0.01 from the Observations of Bright Ellipticals at Yale (OBEY) survey, and 107 early-type galaxies at redshifts 0.2<z<0.7 in the Extended Groth Strip (EGS). Based on these comparisons, we discuss the role of galaxy interactions in the triggering of powerful radio galaxies (PRGs). We find that a significant fraction of quiescent ellipticals at low and intermediate redshifts show evidence for disturbed morphologies at relatively high surface brightness levels, which are likely the result of past or on-going galaxy interactions. However, the morphological features detected in the galaxy hosts of the PRGs (e.g. tidal tails, shells, bridges, etc.) are up to 2 magnitudes brighter than those present in their quiescent counterparts. Indeed, if we consider the same surface brightness limits, the fraction of disturbed morphologies is considerably smaller in the quiescent population (53% at z<0.2 and 48% at 0.2<z<0.7) than in the PRGs (93% at z<0.2 and 95% at 0.2<z<0.7 considering strong-line radio galaxies only). This supports a scenario in which PRGs represent a fleeting active phase of a subset of the elliptical galaxies that have recently undergone mergers/interactions. However, we demonstrate that only a small proportion (<20%) of disturbed early-type galaxies are capable of hosting powerful radio sources.Comment: 20 pages, 7 figures, accepted for publication in MNRA

Contrasting Physiological Responses of Two Populations of the Razor Clam Tagelus dombeii with Different Histories of Exposure to Paralytic Shellfish Poisoning (PSP)

Artículo de publicación ISIThis study describes the physiological performance of two populations of the razor clam Tagelus dombeii from two geographic areas with different histories of exposure to paralytic shellfish poisoning (PSP) linked to the toxic dinoflagellate Alexandrium catenella. Clams from Melinka-Ayse´n, which are frequently exposed to PSP, were not affected by the presence of toxins in the diet. However, clams from Corral-Valdivia, which have never been exposed to PSP, exhibited significantly reduced filtration activity and absorption, affecting the energy allocated to scope for growth (SFG). Ammonia excretion and oxygen uptake were not affected significantly by the presence of A. catenella in the diet. Measurements of energy acquisition and expenditure were performed during a 12-day intoxication period. According to three-way repeated measure ANOVAs, the origin of the clams had a highly significant effect on all physiological variables, and the interaction between diet and origin was significant for the clearance and absorption rates and for the scope for growth. The scope for growth index showed similar positive values for both the toxic and non-toxic individuals from the Melinka-Ayse´n population. However, it was significantly reduced in individuals from Corral-Valdivia when exposed to the diet containing A. catenella. The absence of differences between the physiological response of the toxic and non-toxic clams from Melinka-Ayse´n may be related to the frequent presence of A. catenella in the environment, indicating that this bivalve does not suffer negative consequences from PSP. By contrast, A. catenella has a negative effect on the physiological performance, primarily on the energy gained from the environment, on T. dombeii from Corral-Valdivia. This study supports the hypothesis that the history of PSP exposure plays an important role in the physiological performance and fitness of filter feeding bivalves.File S1 Data for the different physiological variables measured are included in the file S1. (XLSX

Two-way repeated-measures ANOVA for clearance rate, ammonia excretion, oxygen uptake and scope for growth in the razor clam <i>Tagelus dombeii</i>. TE = time of exposure.

<p>* <i>p</i><0.05.</p><p>** <i>p</i><0.01.</p><p>*** <i>p</i><0.001.</p

<i>Tagelus dombeii</i>.

<p>Oxygen uptake measured for a period of 12 days in individuals with different histories of exposure to PSP and exposed to toxic and non-toxic diets (3 replicates per experimental group at each sampling time). A, Melinka, Aysén (with previous PSP exposure); B, Corral, Valdivia (without previous PSP exposure).</p

<i>Tagelus dombeii</i>.

<p>Clearance rate measured on <i>Alexandrium catenella</i> cells for a period of 12 days in individuals with different histories of exposure to PSP. A, Melinka, Aysén (with previous PSP exposure); B, Corral, Valdivia (without previous PSP exposure).</p

Characterization of toxic and non-toxic diets supplied to the razor clam <i>Tagelus dombeii</i>.

<p>Characterization of toxic and non-toxic diets supplied to the razor clam <i>Tagelus dombeii</i>.</p