Artículos

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The OTELO survey: New evidence of downsizing from the specific star formation rates, stellar mass functions, and star formation histories of a sample of low-mass galaxies at 0.38
(Astronomy and Astrophysics, 2025) Cedrés, Bernabé; Bongiovanni, Ángel; Cepa, Jordi; Padilla Torres, Carmen P.; Nadolny, Jakub; Lara López, Maritza Arlene; González Serrano, J. Ignacio; Alfaro, Emilio J.; Cerviño, Miguel; Gallego Maestro, Jesús; González Otero, Mauro; Sánchez Portal, Miguel; de Diego, José A.; Pérez Martínez, Ricardo; Pérez García, Ana María; Pović, Mirjana
Aims. We present an analysis of the emitters (Hα, Hβ, and [O II]) from the OTELO survey, in order to characterize the star formation properties of low-mass galaxies (< 109 M⊙ stellar masses). Methods. We calculated the specific star formation rate function, the stellar mass function, and, by integrating them, the associated densities for both quantities: the specific star formation rate density and the stellar mass density. We obtained the star formation history of our low-mass sample galaxies by fitting the spectral energy distribution of the galaxies. We also compared our results with those from the literature at different mass regimes and redshifts. Results. The specific star formation rate density and the stellar mass density for low-mass galaxies do not depend on the redshift, contrary to the behaviour presented by the high-mass galaxies. We found that the star formation histories of low-mass galaxies are characterized by a constant star formation rate, in contrast to high-mass galaxies. We interpret these results, in the context of the downsizing effect, as representative of the faster evolution of massive galaxies compared with low-mass ones.
Isolated teeth of small theropods from the El Gallo Formation, Baja California, Mexico
(Cretaceous Research, 2026) García-Gil, Vanessa Alexandra; Torices Hernández, Angélica; López Miguel, Mirella; Montellano-Ballesteros, Marisol
In this work, 47 isolated small theropod teeth from different microsites of “El Gallo” Formation, Baja California, Mexico are studied. Isolated theropod teeth constitute important evidence to analyse theropod diversity, since they are quite common in the fossil record. For their identification, we conducted morphological comparisons using multivariate and cladistic analyses comparing them with previously described small theropod teeth from Upper Cretaceous North America Formations. This dental material can be assigned mainly to two families: Dromaeosauridae, Troodontidae; and one subfamily: Saurornitholestinae. Also, some of the teeth were assigned to Richardoestesia and two specimens were indeterminate. Dromaeosaurids represent the most abundant group of theropods in “El Gallo” followed by the Richardoestesia dental Morphotype. This diversity pattern is similar to the one reported in the Aguja Formation of Texas for the same period of time. The use of multivariate statistical techniques and cladistic analyses allowed us to evaluate the similarity between specimens, however, taxonomical assignments are difficult due to the lack of knowledge of intraspecific morphological and/or ontogenetic variation that can lead to misinterpretations. Even so, the sample of 47 specimens yields valuable information that allows suggesting the presence of certain taxa and providing knowledge of the diversity of the continental Cretaceous fauna in Mexico.
Latitude affects continental acidity in the Smithian–Spathian boundary biotic crisis
(Geological Magazine, 2026) Fernández Barrenechea, José María; Borruel Abadía, Violeta; Galán Abellán, Ana Belén; López Gómez, José; Esterle, Joan; McCann, Tom; Horra Del Barco, Raúl De La; Ronchi, Ausonio; Gianolla, Piero; Luque Del Villar, Francisco Javier
The extent to which continental acidity during the Early Triassic varied with latitude remains insufficiently constrained, despite its relevance for understanding environmental stress and biotic recovery patterns across the Smithian–Spathian boundary (SSB). We examined the abundance, textures and compositions of strontium-rich hydrated aluminium phosphate–sulphate (APS) minerals in 179 continental samples spanning tropical to high paleolatitudes in both hemispheres. APS minerals display broadly comparable early-diagenetic features across sections, indicating formation shortly after deposition under acidic meteoric conditions. Their distribution suggests a latitudinal trend: APS contents commonly exceed 0.1 vol.% in equatorial western peri-Tethyan basins, where faunal and floral records are sparse during the SSB, whereas concentrations decrease towards higher latitudes and are rare beyond ∼40° in both hemispheres. This pattern does not appear to correlate with lithological or textural variability and may reflect spatial differences in the intensity or duration of acidification linked to Siberian Traps volcanism. Equatorial basins thus likely experienced more prolonged or recurrent acidic episodes, whereas higher-latitude areas may have been subject to comparatively attenuated effects, potentially contributing to earlier ecological recovery. These results provide a useful framework for evaluating continental acidification and its environmental implications during the interval following the end-Permian mass extinction (EPME).
Viral haemorrhagic septicaemia virus, infectious haematopoietic necrosis virus and HPR‐deleted infectious salmon anaemia virus – Risk of introduction in free areas through fertilised eggs and gametes
(EFSA Journal, 2025) Nielsen, Søren Saxmose; Álvarez Sánchez, Julio; Boklund, Anette; Dippel, Sabine; Figuerola, Jordi; Herskin, Mette S.; Michel, Virginie; Miranda Chueca, Miguel Angel; Nannoni, Eleonora; Nonno, Romolo; Riber, Anja B.; Ståhl, Karl; Stegeman, Jan Arend; Thulke, Hans‐Hermann; Tuyttens, Frank; Winckler, Christoph; Christiansen, Debes Hammershaimb; Olesen, Niels Jørgen; Rimstad, Espen; Toffan, Anna; Vendramin, Niccolò; Papaleo, Stella; Preite, Ludovica; Baldinelli, Francesca; Dórea, Fernanda
EFSA assessed the risk of introducing viral haemorrhagic septicaemia virus (VHSV), infectious haematopoietic necrosis virus (IHNV) and highly polymorphic region-deleted infectious salmon anaemia virus (HPR-deleted ISAV) into free areas through movement of fertilised eggs and gametes. No evidence of true vertical transmission of these viruses was found. However, viral contamination of the surface of fertilised eggs and gametes cannot be ruled out. Assuming full compliance with the recommendations in the new draft 4.Z chapter of the Aquatic Animal Health Code of the World Organisation for Animal Health, including individual testing of broodfish at stripping, the median probability of introduction following importation of fertilised eggs was 0.36% for VHSV and IHNV, and 0.4% for HPR-deleted ISAV. The median probabilities were reduced to 0.02% and 0.01%, respectively, if fertilised eggs were disinfected twice (as green and as eyed eggs) at origin. Additional disinfection upon arrival in the importing establishment reduced the median probability to 0.02% for all viruses with one disinfection at the origin, and to virtually zero when two disinfections were applied at the origin. The assessment also evaluated probability of introduction when only population testing before stripping is applied. Two disinfections at the origin plus one at destination also resulted in virtually zero probability of introduction. For gametes, individual testing of broodfish at stripping, along with the other risk mitigation measures recommended in the new chapter resulted in a probability of introduction ranging from 0% to 0.3%. Implementation of the measures included in the new draft 4.Z chapter is recommended to prevent the introduction of VHSV, IHNV and HPR-deleted ISAV when moving gametes and fertilised eggs from non-free to free areas. In addition, it is recommended that fertilised eggs are disinfected twice before being traded and, to further reduce the risk, also disinfected at the establishment receiving the imported materials.
Tailored hotspots from Airy-based surface plasmon polaritons
(Physical Review B, 2025) Martínez Herrero, María Rosario; Sanz Ortiz, Ángel Santiago; Hernández Rueda, Francisco Javier
Surface plasmons have attracted growing interest from the photonics community due to their inherent ability to controllably confine light below the diffraction limit and their direct application in trapping and transporting matter at the nanoscale. This method, known as plasmonic tweezers, employs confined fields generated by either localized plasmons or surface plasmon polaritons (SPP), which originate in the vicinity of nanostructure-based traps or across structureless platforms, respectively. Herein, we present a theoretical method for generating intense light hotspots and engineering their features by overlapping Airy SPPs (ASPP) at a smooth dielectric-metal interface. We coherently add pairs of Hermite-Gauss modes that belong to a complete basis set of finite-energy ASPPs, which yield highly confined plasmonic hotspots (approximate to lambda/10) without the need of using any nanostructured platform. Mode order and relative spacing parameters can be used to tailor the intensity and size of said hotspots, largely outperforming their Gaussian-only-based counterparts. Our method opens a promising venue to confine light at the nanoscale using ASPP-based structured light, which helps to advance the development of structureless plasmonic tweezers and holds promising potential for its application in optical signal processing and plasmonic circuitry.
The last of Europe: systematics and palaeoecology of the ictitheres (Hyaenidae) from Venta del Moro (Spain)
(Journal of Mammalian Evolution, 2026) Kargopoulos, Nikolaos; Morales Flores, David; Montoya, Plini; Valenciano Vaquero, Alberto; De Miguel, Daniel; Morales, Jorge; Abella, Juan
Venta del Moro is one of the most exceptional localities in the Miocene of Europe due to its chronostratigraphic position and its unusual fauna, which includes taxa of African and Asian origin. The hyaenids of this locality belong to the group of ictitheres, dog-like hyenas that roamed Eurasia and Africa until their sudden decline at the latest Miocene and their subsequent ecological replacement by the canids. The ictithere record of Venta del Moro is crucial to our understanding of hyaenid evolution, since it represents the last accurately dated occurrence of ictitheres in Europe, and one of the very few cases of coexistence between ictitheres and canids. The bulk of the discovered craniodental material is identified as Hyaenictitherium wongii, an abundant species with a wide distribution and morphometric range in the Turolian of Eurasia. However, four isolated teeth correspond to a larger, unidentified ictithere that may represent one of the Asian immigrants present at the locality. A preliminary review of the genus Hyaenictitherium is conducted, emphasising the importance of intraspecific variability throughout its temporospatial range. This allows us to discuss the validity of several species, noting that a thorough review with firsthand study of old material is required. In palaeoecological terms, H. wongii was, according to our current knowledge, a coyote-like, cursorial animal, with advanced adaptations for durophagy, larger and more robust than the coexisting Eucyon debonisi. This relationship between canids and ictitheres is seen in other localities in Eurasia and Africa, showing that the dynamics of the aforementioned transition are complex and cannot be explained solely by the Eurasian dispersal of canids.
Evaluation of the new role of the invasive species (Procambarus clarkii) as an environmental indicator in polluted watersheds
(Environmental Geochemistry and Health, 2026) Barquero Peralbo, Jose Ignacio; Higueras Higueras, Pablo; Esbrí Víctor, José María; Jaeger, Judith L.; García Ordiales, Efrén
Procambarus clarkii represents an invasive species of crayfish common in the rivers of the Iberian Peninsula, which replaced a previous invasive species of crayfish (Austropotamobius pallipes) and is now being replaced by a new invasive species (Pacifastacus leniusculus) in northern rivers. Leaving aside the ecological problems that these invasive species can cause, these organisms can be excellent candidates to act as environmental indicators in pollution processes that involves the interface water–sediment. In this work, the potential role of Procambarus clarkii as a bioindicator of pollution processes of mining origin is evaluated. Unlike previous research, which often focuses on snapshot assessments of contamination levels, our approach integrates historical data and continuous monitoring to provide a dynamic perspective on the impact of Hg and other metals on biotic and abiotic media over an extended period. A total of 330 crayfish were collected from 10 sites in Valdeazogues river, grouped by size, and analyzed for Hg, Pb, Cd, Cu, Zn, As, and Sb in abdominal muscle and hepatopancreas, with a complete characterization of sediment and water media. Crayfish data have shown that hepatopancreas and muscle present the highest average content of Zn (1,325 and 377 mg kg−1, respectively) and Cu (1,297 and 179 mg kg−1 respectively). Levels of Hg were higher in muscle (1.6 mg kg−1) than hepatopancreas (1.0 mg kg−1), with all muscle samples exceeding the EU maximum permissible level of 0.5 mg kg−1 for food. The sensitivity of P. clarkii has been sufficient to identify different sources of Hg, Pb and Zn contamination in the drainage system, and even agricultural sources of Cd downstream of the mining district. This versatile capability can be of application to large mining areas in the south of the Iberian Peninsula, especially throughout the Iberian Pyrite Belt.
Wildlife risk mitigation protocols reduce risk species visits and pathogen marker detection in open-air farms
(Veterinary Research, 2025) Marín-Rojo, Ángela; Herrero-García, Gloria; Herranz Benito, Carmen; Barroso, Patricia; Relimpio, David; García-Seco Romero, María Teresa; Perelló, Alberto; Díez Guerrier, Alberto Antoine; Pozo Piñol, Pilar; Balseiro, Ana; Domínguez Rodríguez, Lucas José; Pérez Sancho, Marta; Gortázar, Christian
Outdoor farming systems may favor the dilution effect of biodiversity on pathogen exposure and contribute to biodiversity conservation through the preservation of valuable habitats. However, owing to the implicit closer interaction with wildlife, outdoor farms are also more at risk for disease maintenance at the wildlife–livestock interface. Disease control options in outdoor farming systems include the development and application of wildlife risk mitigation protocols (RMPs). However, while the nature of the proposed mitigation actions and the degree of farmer uptake have repeatedly been assessed, only limited information exists on their effectiveness. In this study, we revisited 14 farms of a pilot study to quantify the effect of applying RMPs on the detection rates of risk wildlife (assessed by means of camera traps [CTs]) and of selected pathogen markers (using sponges for environmental nucleic acid detection [ENAD]). The application of farm-specific RMPs resulted in a 30% reduction in farm visits by high-risk wildlife and an 18% reduction in the frequency of pathogen marker detection. High-risk species detection declined on 11 farms and increased on 3, all of them small ruminant farms. Regarding pathogen markers, we observed frequency reductions for four markers and increases for two markers. These changes were statistically significant for the Salmonella spp. marker invA. At the farm level, the reduction in the detection frequency of wild boar (Sus scrofa) correlated with the reduction in the detection frequency of the invA marker. These noninvasive methods may be relevant for assessing other interventions at the wildlife–livestock interface, regardless of the farmed species, farming system, and target pathogen.
Endolithic microbial habitats as refuges for life in polyextreme environment of the Atacama Desert
(Current Opinion in Microbiology, 2018) Wierzchos, Jacek; Casero Chamorro, María Cristina; Artieda, Octavio; Ascaso, Carmen
The extremely harsh conditions of hyperarid deserts are a true challenge for microbial life. Microorganisms thriving in such polyextreme environments are fascinating as they can tell us more about life, its strategies and its boundaries than other groups of organisms. The Atacama Desert (North Chile) holds two world records of extreme environmental characteristics: the lowest rainfall and greatest surface ultraviolet radiation and total solar irradiance ever measured on Earth. Despite these limiting conditions for life, we recently identified several remarkable examples of endolithic habitats colonized by phototrophic and heterotrophic microorganisms in the hyperarid core of the Atacama Desert.
Prevalencia de malnutrición en pacientes hospitalizados por descompensación de insuficiencia cardiaca crónica; valoración subjetiva global como indicador pronóstico
(Nutrición hospitalaria, 2015) Guerra Sánchez, Luis; Martínez Rincón, María Del Carmen; Fresno Flores, Mar
Existe una gran variabilidad en los estudios sobre la prevalencia de malnutrición en pacientes con insuficiencia cardiaca crónica. La proporción de pacientes desnutridos depende del método de valoración utilizado y del momento en que se realice. Se ha descrito la relación entre desnutrición y aumento de las complicaciones, así como de la estancia hospitalaria, la mortalidad y el reingreso hospitalario. Por lo que merece la pena señalar y tratar a estos pacientes. Objetivos: El objetivo fue aproximarnos a la prevalencia de la desnutrición, en los pacientes con insuficiencia cardiaca crónica ingresados por descompensación, en nuestro medio y analizar cuál de los dos métodos de valoración nutricional utilizados, era mejor predictor de mortalidad. Métodos: Estudio observacional, transversal, en el que se evaluaron mediante la Valoración Subjetiva Global y Mini Nutritional Assesment , el estado nutricional de 377 pacientes ingresados en un hospital terciario de alta complejidad con diagnósticos compatibles con descompensación de insuficiencia cardiaca crónica. Resultados: La edad media fue de 75±10. El 51,5% (n=194) fueron hombres. Según la Valoración Subjetiva Global, el 50,7% (45,6%-55,7%) estaban normonutridos, el 41,9% (37,0%-46,9%) presentaban riesgo o sospecha de desnutrición y el 7,4% (5,2%-10,5%) presentaban desnutrición franca. Conclusiones: La prevalencia de desnutrición de los pacientes hospitalizados por descompensación de insuficiencia cardiaca crónica en nuestro ámbito es alta. La Valoración Subjetiva Global es un buen predictor de la mortalidad.
Algebrability and Riemann integrability of the composite function
(Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas (RACSAM), 2024) D'Aniello, E.; Fernández Sánchez, Juan; Maiuriello, M.; Seoane Sepúlveda, Juan Benigno
In this note, we show that there exist a 2c-generated free algebra S ⊂ RR of Riemann integrable functions and a free algebra C ⊂ R[0,1] of continuous functions, having c-generators, such that r ◦ c is not Riemann integrable for any r ∈ S and c ∈ C. This result is the best possible one in terms of lineability within these families of functions and, at the same time, an improvement of a previous result ([6, Theorem 2.7]). In order to achieve our results we shall employ set theoretical tools such as the Fichtenholz-Kantorovich-Hausdorff theorem, Cantor-Smith-Volterra–type sets, and classical real analysis techniques.
Beyond conglomerates: a minimalist model of the Viedma Deracemization of dl-amino acids
(Crystal Growth and Design, 2025) Micheau, Jean-Claude; Buhse, Thomas; Cintas Moreno, Pedro; Ortiz, José E.; Ribó, Josep M.; Viedma Molero, Cristóbal
A comprehensive kinetic rate equation model is proposed for a better understanding of the Viedma deracemization of dl-amino acids. This model includes monomer plus cluster and cluster plus cluster growth, and involves both homochiral and heterochiral interactions. Our approach employs a fully microreversible growth and dissolution kinetic scheme. It works with an irreversible cluster breaking by grinding under racemizing condition of molecules. The model which is consistent with experimental observations has been parametrized on the amplification of the enantiomeric excess during the total deracemization of a scalemic mixture of dl- and l-crystals of aspartic acid. After parametrization, numerical simulations show the possibility of spontaneous mirror symmetry breaking (SMSB). Furthermore, we identify a bifurcation scenario where it is predicted that, as long as the energy difference between racemic and enantiopure crystals is not too high, Viedma deracemization may be possible under sufficient nonequilibrium conditions. However, there are situations where the deracemization success requires an initial enantiomeric excess higher than a critical value. Our model predictions have been validated by the complete deracemization of two proteinogenic amino acids, namely dl-aspartic acid and dl-valine racemic crystals.
Toxoplasma gondii and Neospora caninum in naturally infected synanthropic (Muridae) and wild (Cricetidae) rodents from Argentina
(Parasitology International, 2026) Bentancourt Rossoli, Judith V.; Campero, Lucía María; Moré, Gastón; Soto-Cabrera, Agustina; Moore, Dadín P.; Morrell, Eleonora L.; Scioli, María V.; Basso, Walter; Hecker, Yanina Paola; Scioscia, Nathalia P.
Rodents serve as reservoir hosts for many parasites, including the closely related intracellular protozoan parasites Toxoplasma gondii and Neospora caninum, which are regarded as major causes of abortion in ruminants. This study investigated T. gondii and N. caninum infections in synanthropic (Muridae) and wild (Cricetidae) rodents from rural areas in the Pampas Region, Argentina, using histological, serological, and molecular methods. We also genetically characterized T. gondii isolates. A total of 356 rodents were captured, comprising both murid (Mus musculus, Rattus norvegicus, R. rattus) and cricetid (Oxymycterus rufus, Necromys spp., Akodon azarae, Oligoryzomys flavescens, Calomys musculinus, C. laucha) species. Histological examination did not reveal tissue cysts of these parasites. However, antibodies for T. gondii and N. caninum were detected in 9.8 % (35/356) and 1.7 % (6/356) of the samples using the indirect immunofluorescent antibody test (IFAT). T. gondii DNA was detected by qPCR in brain samples from two of the 41 seropositive rodents. Multilocus PCR-RFLP revealed atypical T. gondii genotypes in both samples. N. caninum DNA was not detected by PCR in any sample. This study provides the first serological and molecular evidence of T. gondii and N. caninum in Cricetidae rodents from Argentina, including the first genotyping data. The detection of T. gondii DNA exclusively in wild rodents highlights the role of wildlife in parasite transmission.
Características de la insuficiencia tricúspide grave inducida por dispositivos de estimulación intracardiacos
(Medicina Clínica, 2024) De Agustín Loeches, José Alberto; Orlando Figueroa; Carmen Olmos Blanco; Eduardo Pozo Osinalde; Patricia Casado; Luaces Méndez, María; María Rivadeneira; Pedro Marcos-Alberca; Jose Juan Gómez de Diego; Collado Yurrita, Luis Rodolfo; Fernández Ortiz, Antonio Ignacio; Pérez Villacastín Domínguez, Julián
Introducción y objetivos La insuficiencia tricúspide (IT) inducida por el implante de dispositivos de estimulación intracardiacos (DEIC) es una causa cada vez más frecuente de IT grave. Nuestro objetivo fue describir las características ecocardiográficas de la IT grave inducida por DEIC. Métodos Estudio de cohortes retrospectivo que incluyó a los pacientes con IT grave relacionada con DEIC diagnosticada en la unidad de imagen cardiaca de un hospital terciario español. Resultados Un total de 37 pacientes con IT grave inducida por la interferencia del cable/electrodo formaron nuestro grupo de estudio. La IT fue predominante grave (68%), seguida de masiva (21%) y torrencial (11%). El velo más afectado por la interferencia fue el septal. Un 58% de la muestra presentó dilatación grave de la aurícula derecha (AD) (media de área AD 28 cm2). La media del anillo tricúspide fue de 42 mm. Los parámetros usuales de cuantificación de la función sistólica del VD se encontraron en promedio dentro del rango normal (media TAPSE 19 mm, onda S’ 10 mm, FAC 41%), mientras que el strain global del VD (RVGLS -15%) y el strain de pared libre (RVFWLS -19%) se encontraron reducidos. Se evidenció un grado incipiente de desacoplamiento ventrículo/arterial pulmonar (media TAPSE/PSAP 0,34, SGLVD/PSAP 0,27%/mmHg). Conclusiones Nuestros pacientes con IT grave inducida por DEIC se caracterizan por un fenotipo heterogéneo con alta prevalencia de dilatación grave de AD y anillo tricúspide. El RVGLS, RVFWLS y el acoplamiento ventriculoarterial resultaron los parámetros más sensibles para la evaluación precoz de la disfunción sistólica del VD.
Cribado nutricional en pacientes con insuficiencia cardiaca: análisis de 5 métodos
(Nutrición Hospitalaria, 2015) Guerra Sánchez, Luis; Martínez Rincón, María Del Carmen; Fresno Flores, Mar
Introduccion: La malnutrición aumenta la mortalidad y la estancia hospitalaria. Cada vez más instituciones sanitarias adoptan medidas de cribado nutricional con el fin de detectar precozmente la malnutrición o el riesgo de desarrollarla. No existe un método universalmente aceptado para la valoración nutricional. Objetivo: Determinar un método rápido y fiable, que no precise de entrenamiento previo, para el cribado nutricional de pacientes con insuficiencia cardiaca. Métodos: Estudio observacional, transversal, en el que se evaluaron mediante la valoración subjetiva global (VSG), el Mini nutritional assesment (MNA) tanto en su versión abreviada o de cribado (MNA-SF) como en su versión extendida o de valoración (MNA-LF), el nutritional Risk Screnning (NRS 2002), el Conocimiento nutricional o método Ulibarri (CONUT), el método Cardona y el Malnutrition Universal Screening Tool (MUST), el estado nutricional de 242 pacientes ingresados en un hospital terciario de alta complejidad con diagnósticos compatibles con descompensación de insuficiencia cardiaca crónica. Se analizaron la sensibilidad, especificidad, los valores predictivos, las razones de verosimilitud, la odds ratio diagnostica y el índice de correlación kappa, de los distintos métodos comparados con la valoración subjetiva global, que fue considerada como prueba cierta. Resultados: La edad media fue de 75±9. El 50,8% (n=123) fueron hombres. El índice de correlación kappa de los distintos métodos de cribado con respecto a la valoración subjetiva global fueron MNA valoración =0,637; MNA cribado =0,556; NRS =0,483; MUST =0,197; Cardona =0,188; CONUT =0,076. Discusión: El Mini Nutritional Assesment fue el método que mejor relación ofreció, tanto en su etapa de cribado como en la de valoración con la Valoración subjetiva global.
Aportación del laboratorio de microbiología al diagnóstico de la neumonía asociada a la ventilación mecánica
(Enfermedades infecciosas y microbiología clínica, 2005) Bouza Santiago, Emilio; Torres, María V.; Burillo Albizua, Almudena
Este artículo analiza de forma detallada el papel del laboratorio de microbiología en el diagnóstico etiológico de la neumonía asociada a la ventilación mecánica (NAVM), una de las principales causas de infección nosocomial y de mortalidad en las unidades de cuidados intensivos. Los autores subrayan que la NAVM debe considerarse una urgencia microbiológica, dado que el retraso en el inicio de un tratamiento antimicrobiano adecuado se asocia a peor pronóstico. Se revisan los microorganismos más frecuentemente implicados, destacando Staphylococcus aureus, enterobacterias y bacilos gramnegativos no fermentadores como Pseudomonas aeruginosa y Acinetobacter baumannii, así como el limitado papel de anaerobios, hongos y virus en pacientes inmunocompetentes. El trabajo aborda de manera crítica los distintos métodos de obtención de muestras del tracto respiratorio inferior, comparando procedimientos broncoscópicos y no broncoscópicos, y resalta la importancia de los cultivos cuantitativos para diferenciar colonización de infección. Se analiza el valor diagnóstico del aspirado endotraqueal, el catéter telescopado y el lavado broncoalveolar, así como la utilidad de la tinción de Gram como herramienta rápida para orientar el tratamiento empírico inicial. Finalmente, se revisan los procedimientos de antibiograma rápido realizados directamente sobre muestras clínicas y se enfatiza la necesidad de una comunicación estrecha entre microbiólogos e intensivistas para optimizar el uso de antimicrobianos y mejorar el pronóstico de los pacientes.
Viable microorganisms on fibers collected within and beyond the planetary boundary layer
(Environmental Science & Technology Letters, 2020) González Pleiter, Miguel; Edo, Carlos; Casero, María Cristina; Aguilera, Ángeles; González Toril, Elena; Wierzchos, Jacek; Leganés, Francisco; Fernández Piñas, Francisca; Rosal, Roberto
Fibers are found in all environments. However, the impact of their presence on ecosystems and human health is not yet well understood, especially in the case of the atmosphere. In this work, we presented evidence that fibers traveling through the atmosphere act as vectors to spread microorganisms. Here, we investigated the presence of viable microorganisms on fibers collected within and beyond the planetary boundary layer during flights of C-212 aircraft over Central Spain. In total, seven fibers, six of which transported viable microorganisms, were isolated in two flights. The viability of the microorganisms was determined by confocal microscopy by means of the fluorescent probes SYBR-Green to detect microorganisms and CTC redox dye to assess their cellular respiration activity. The fibers that transported viable microorganisms were spectroscopically analyzed by micro-FTIR and identified as wool-silk and cellulose-cotton. Taken together, the results demonstrated that fibers host viable microorganisms when traveling through the lower free troposphere.
Percepciones y usos de la inteligencia artificial en el profesorado universitario: un análisis desde la perspectiva de género
(Investigaciones Feministas, 2025) Blázquez Rodríguez, María Isabel; Vartabedian Cabral, Julieta Luciana; Mancha Cáceres, Olga Inmaculada; Pichardo Galán, José Ignacio
Introducción: Este artículo analiza las percepciones del profesorado universitario sobre el uso de la inteligencia artificial (IA) en los procesos de enseñanza-aprendizaje desde una perspectiva de género. El objetivo principal es explorar cómo las herramientas de IA son utilizadas en la actividad docente y examinar posibles diferencias sexo-genéricas en las actitudes y preocupaciones del profesorado sobre su impacto. Metodología: Se aplicó un cuestionario, completado por 133 docentes universitarios de diversas áreas del conocimiento, incorporando un enfoque con perspectiva de género para identificar patrones en el uso y las actitudes hacia la IA. Resultados: Los datos muestran un uso generalizado de herramientas de IA entre el profesorado universitario, con diferencias moderadas en las actitudes y preocupaciones entre hombres y mujeres. Aunque estas diferencias no resultan estadísticamente significativas, se observan tendencias como una mayor cautela y reflexión crítica entre las docentes respecto al impacto y al uso de la IA en los procesos de enseñanza-aprendizaje. Discusión/Aportación: Aunque esta investigación no puede generalizar sus hallazgos al conjunto del profesorado universitario, el alto número de respuestas y la diversidad disciplinar aportan información empírica valiosa en un campo poco estudiado. Los resultados subrayan la necesidad de desarrollar estrategias formativas e institucionales que promuevan un uso ético, inclusivo y efectivo de la IA en la educación superior.
Analytic families of operators in extrapolation theory with application to average operators
(The mathematical heritage of Guido Weiss, 2026) Carro Rossell, María Jesús
Our goal is to prove weak type boundedness for an operator which is given as an average of a family of operators satisfying certain estimates in the context of weighted Lebesgue spaces. Our main technique is inspired on the theory of analytic families of operators and it is closely related to the Rubio de Francia’s extrapolation theory.
The Zaremba problem in two-dimensional Lipschitz graph domains
(Transactions of the American Mathematical Society, 2025) Carro Rossell, María Jesús; Luque Martínez, Teresa Elvira; Naibo, V.
We study the Zaremba problem, or mixed problem associated to the Laplace operator, in two-dimensional Lipschitz graph domains with mixed Dirichlet and Neumann boundary data in Lebesgue and Lorentz spaces. We obtain an explicit value such that the Zaremba problem is solvable in for Lp and in the Lorentz space L(p,1). Applications include those where the domain is a cone with vertex at the origin and, more generally, a Schwarz–Christoffel domain. The techniques employed are based on results of the Zaremba problem in the upper half-plane, the use of conformal maps and the theory of solutions to the Neumann problem. For the case when the domain is the upper half-plane, we work in the weighted setting, establishing conditions on the weights for the existence of solutions and estimates for the non-tangential maximal function of the gradient of the solution. In particular, in the unweighted case, where known examples show that the gradient of the solution may fail to be squared-integrable, we prove restricted weak-type estimates.

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