Soluciones estables en juegos cooperativos bajo incertidumbre

Los juegos cooperativos con múltiples escenarios modelan situaciones de decisión bajo incertidumbre, cuando se tiene que repartir un bien entre un conjunto de individuos, teniendo en cuenta los valores de las coaliciones bajo diferentes escenarios simultáneamente o bajo diferentes estados de la naturaleza. En este trabajo se proponen y analizan diferentes conceptos de solución para este tipo de juegos y se proporcionan procedimientos para calcular los repartos que generan. En particular, se introducen los núcleos de ponderación como solución y se analizan las relaciones entre estos y los conceptos existentes en la literatura: núcleo de preferencia y núcleo de dominancia. A continuación, se considera la posibilidad de incorporar información parcial sobre las probabilidades de ocurrencia de los distintos escenarios con objeto de obtener conjuntos de repartos que sean estables cuando se dispone de información probabilística. Para ello se presentan nuevos conceptos de núcleo con información parcial que extienden las nociones de núcleo de preferencia y núcleo de dominancia. Se investigan las relaciones entre ellos y se proporciona el procedimiento para el cálculo de los resultados que generan.Multiple scenario cooperative games model situations where the worth of the coalitions is valued in several scenarios simultaneously or under diferent states of nature. We focus on the identification of those allocations which are stable in the sense that agents have no incentives to abandon the group. The stability of an allocation depends on how the quantities the coalitions obtain are compared with the vector-valued worth of the coalition, therefore, different extensions of the notion of core emerge, depending on how these comparisons are made. We introduce the new notions of weighting cores and analize the relationships between them and the existing core solutions. We also address the inclusion in the model of partial information about the probabilities of occurrence of the scenarios. In order to identify allocations which are also stable in the presence of probability information, we extend the notions of core to this new setting, and provide results which permit the efective calculation of the corresponding sets of allocations

Soluciones Estables en Juegos Cooperativos bajo Incertidumbre

Los juegos cooperativos con múltiples escenarios modelan situaciones de decisión bajo incertidumbre, cuando se tiene que repartir un bien entre un conjunto de individuos, teniendo en cuenta los valores de las coaliciones bajo diferentes escenarios simult ́aneamente o bajo diferentes estados de la naturaleza. En este trabajo se proponen y analizan diferentes conceptos de solución para este tipo de juegos y se proporcionan procedimientos para calcular los repartos que generan. En particular, se introducen los núcleos de ponderaci ́on como solución y se analizan las relaciones entre ́estos y los conceptos existentes en la literatura: núcleo de preferencia y núcleo de dominancia. A continuación, se considera la posibilidad de incorporar informaci ́on parcial sobre las probabilidades de ocurrencia de los distintos escenarios con objeto de obtener conjuntos de repartos que sean estables cuando se dispone de información probabilística. Para ello se presentan nuevos conceptos de núcleo con información parcial que extienden las nociones de núcleo de preferencia y núcleo de dominancia. Se investigan las relaciones entre ellos y se proporciona el procedimiento para el c ́alculo de los resultados que generan.Multiple scenario cooperative games model situations where the worth of the coalitions is valued in several scenarios simultaneously or under different states of nature. We focus on the identification of those allocations which are stable in the sense that agents have no incentives to abandon the group. The stability of an allocation depends on how the quantities the coalitions obtain are compared with the vector-valued worth of the coalition, therefore, different extensions of the notion of core emerge, depending on how these comparisons are made. We introduce the new notions of weighting cores and analize the relationships between them and the existing core solutions. We also address the inclusion in the model of partial information about the probabilities of occurrence of the scenarios. In order to identify allocations which are also stable in the presence of probability information, we extend the notions of core to this new setting, and provide results which permit the efective calculation of the corresponding sets of allocations

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe

Base de datos de abejas ibéricas

Las abejas son un grupo extremadamente diverso con más de 1000 especies descritas en la península ibérica. Además, son excelentes polinizadores y aportan numerosos servicios ecosistémicos fundamentales para la mayoría de ecosistemas terrestres. Debido a los diversos cambios ambientales inducidos por el ser humano, existen evidencias del declive de algunas de sus poblaciones para ciertas especies. Sin embargo, conocemos muy poco del estado de conservación de la mayoría de especies y de muchas de ellas ignoramos cuál es su distribución en la península ibérica. En este trabajo presentamos un esfuerzo colaborativo para crear una base de datos de ocurrencias de abejas que abarca la península ibérica e islas Baleares que permitirá resolver cuestiones como la distribución de las diferentes especies, preferencia de hábitat, fenología o tendencias históricas. En su versión actual, esta base de datos contiene un total de 87 684 registros de 923 especies recolectados entre 1830 y 2022, de los cuales un 87% presentan información georreferenciada. Para cada registro se incluye información relativa a la localidad de muestreo (89%), identificador y colector de la especie (64%), fecha de captura (54%) y planta donde se recolectó (20%). Creemos que esta base de datos es el punto de partida para conocer y conservar mejor la biodiversidad de abejas en la península ibérica e Islas Baleares. Se puede acceder a estos datos a través del siguiente enlace permanente: https://doi.org/10.5281/zenodo.6354502ABSTRACT: Bees are a diverse group with more than 1000 species known from the Iberian Peninsula. They have increasingly received special attention due to their important role as pollinators and providers of ecosystem services. In addition, various rapid human-induced environmental changes are leading to the decline of some of its populations. However, we know very little about the conservation status of most species and for many species, we hardly know their true distributions across the Iberian Peninsula. Here, we present a collaborative effort to collate and curate a database of Iberian bee occurrences to answer questions about their distribution, habitat preference, phenology, or historical trends. In total we have accumulated 87 684 records from the Iberian Peninsula and the Balearic Islands of 923 different species with 87% of georeferenced records collected between 1830 and 2022. In addition, each record has associated information such as the sampling location (89%), collector and person who identified the species (64%), date of the capture (54%) and plant species where the bees were captured (20%). We believe that this database is the starting point to better understand and conserve bee biodiversity in the Iberian Peninsula. It can be accessed at: https://doi.org/10.5281/zenodo.6354502Esta base de datos se ha realizado con la ayuda de los proyectos EUCLIPO (Fundação para a Ciência e a Tecnologia, LISBOA-01-0145-FEDER-028360/EUCLIPO) y SAFEGUARD (ref. 101003476 H2020 -SFS-2019-2).info:eu-repo/semantics/publishedVersio

Obtención y purificación de Ficocianinas mediante cromotagrofía de adsorción en lecho expandido. Escalado del proceso, caracterización fisicoquímica y aplicación como colorantes naturales

En esta Tesis, se ha llevado a cabo la purificación de ficocianinas procedentes de microalgas a través de una metodología escalable. Las ficocianinas se extraen de las células utilizando choque osmótico y se purifican por cromatografía de adsorción en lecho expandido (CALE) usando Streamline-DEAE como adsorbente. La disolución rica en C-PC que se obtiene, se purifica con cromatografía convencional de lecho empaquetado usando DEAE-celulosa (intercambio iónico). Tanto las condiciones de extracción como las de operación de CALE han sido optimizadas. Las etapas de purificación se monitorizan utilizando SDS-PAGE y la pureza de las ficocianinas recuperadas se confirma por espectroscopía de absorción y de emisión y RP-HPLC. Los resultados muestran que el método CALE es una tecnología escalable que permite obtener grandes cantidades de ficocianinas, manteniendo una alta recuperación de proteína, a la vez que se reducen el tiempo de operación y el coste. Además, se ha demostrado el potencial de las ficocianinas como colorantes naturales en alimentos y bebidas utilizando diferentes productos comerciales.In this Thesis a large and scaleable method for purification of phycocyanins from cyanobacteria microalgae has been developed. Phycocyanins are extracted from the cells by osmotic shock and separated by expanded bed adsorption chromatography (EBAC) using Streamline-DEAE as adsorbent. The eluted phycocyanins rich solution is finally purified by packed-bed chromatography using DEAE-cellulose. Both the extraction conditions and the operation of EBAC are optimized. To obtain pure C-PC, conventional ion-exchange chromatography with DEAE-cellulose is utilized. The purification steps are monitored using SDS-PAGE and the purity of recovered phycocyanins is confirmed by absorption and emission spectroscopy and RP-HPLC. Results show that EBAC method is a scalable technology that allows large quantities of phycocyanins to be obtained without product loss, maintaining a high protein recovery while reducing both processing cost and time. So, the potential of phycocyanins as natural colorants is demonstrated using different food and drink commercial products.Tesis Univ. Jaén. Departamento de Química Física y Analítica. Leída el 28 de abril de 201

Soluciones Estables en Juegos Cooperativos bajo Incertidumbre.

Multiple scenario cooperative games model situations where the worth of the coalitions is valued in several scenarios simultaneously or under di erent states of nature. We focus on the identification of those allocations which are stable in the sense that agents have no incentives to abandon the group. The stability of an allocation depends on how the quantities the coalitions obtain are compared with the vector-valued worth of the coalition, therefore, diferent extensions of the notion of core emerge, depending on how these comparisons are made. We introduce the new notions of weighting cores and analize the relationships between them and the existing core solutions. We also address the inclusion in the model of partial information about the probabilities of occurrence of the scenarios. In order to identify allocations which are also stable in the presence of probability information, we extend the notions of core to this new setting, and provide results which permit the efective calculation of the corresponding sets of allocations.Los juegos cooperativos con múltiples escenarios modelan situaciones de decisión bajo incertidumbre, cuando se tiene que repartir un bien entre un conjunto de individuos, teniendo en cuenta los valores de las coaliciones bajo diferentes escenarios simultáneamente o bajo diferentes estados de la naturaleza. En este trabajo se proponen y analizan diferentes conceptos de solución para este tipo de juegos y se proporcionan procedimientos para calcular los repartos que generan. En particular, se introducen los núcleos de ponderación como solución y se analizan las relaciones entre éstos y los conceptos existentes en la literatura: núcleo de preferencia y núcleo de dominancia. A continuación, se considera la posibilidad de incorporar información parcial sobre las probabilidades de ocurrencia de los distintos escenarios con objeto de obtener conjuntos de repartos que sean estables cuando se dispone de información probabilitica. Para ello se presentan nuevos conceptos de núcleo con información parcial que extienden las nociones de nucleo de preferencia y nucleo de dominancia. Se investigan las relaciones entre ellos y se proporciona el procedimiento para el cálculo de los resultados que generan

Utilización de biliproteínas como colorantes naturales en alimentación

En la actualidad, la mayor parte de los colorantes que se utilizan son de origen sintético y muchos de ellos pueden provocar reacciones tóxicas en individuos susceptibles. Así, existe un interés creciente en la búsqueda de nuevas moléculas con capacidad colorante, que puedan contribuir a ampliar el catálogo de los colorantes naturales existentes en el mercado. Nuestro grupo de investigación, ha desarrollado una nueva metodología para la obtención de biliproteínas procedentes de microalgas y ha ensayado su capacidad colorante en diversos alimentos

Local Unfolding Is Required for the Site-Specific Protein Modification by Transglutaminase

The transglutaminase (TGase) from <i>Streptomyces mobaraensis</i> catalyzes transamidation reactions in a protein substrate leading to the modification of the side chains of Gln and Lys residues according to the A-CONH₂ + H₂N-B → A-CONH-B + NH₃ reaction, where both A and B can be a protein or a ligand. A noteworthy property of TGase is its susbstrate specificity, so that often only a few specific Gln or Lys residues can be modified in a globular protein. The molecular features of a globular protein dictating the site-specific reactions mediated by TGase are yet poorly understood. Here, we have analyzed the reactivity toward TGase of apomyoglobin (apoMb), α-lactalbumin (α-LA), and fragment 205–316 of thermolysin. These proteins are models of protein structure and folding that have been studied previously using the limited proteolysis technique to unravel regions of local unfolding in their amino acid sequences. The three proteins were modified by TGase at the level of Gln or Lys residues with dansylcadaverine or carbobenzoxy-l-glutaminylglycine, respectively. Despite these model proteins containing several Gln and Lys residues, the sites of TGase derivatization occur over restricted chain regions of the protein substrates. In particular, the TGase-mediated modifications occur in the “helix F” region in apoMb, in the β-domain in apo-α-LA in its molten globule state, and in the N-terminal region in fragment 205–316 of thermolysin. Interestingly, the sites of limited proteolysis are located in the same chain regions of these proteins, thus providing a clear-cut demonstration that chain flexibility or local unfolding overwhelmingly dictates the site-specific modification by both TGase and a protease