Universidad de Sevilla
Recent publications
This letter addresses the problem of trajectory planning in a marsupial robotic system consisting of an unmanned aerial vehicle (UAV) linked to an unmanned ground vehicle (UGV) through a non-taut tether with controllable length. To the best of our knowledge, this is the first method that addresses the trajectory planning of a marsupial UGV-UAV with a non-taut tether. The objective is to determine a synchronized collision-free trajectory for the three marsupial system agents: UAV, UGV, and tether. First, we present a path planning solution based on optimal Rapidly-exploring Random Trees (RRT*) with novel sampling and steering techniques to speed-up the computation. This algorithm is able to obtain collision-free paths for the UAV and the UGV, taking into account the 3D environment and the tether. Then, the letter presents a trajectory planner based on non-linear least squares. The optimizer takes into account aspects not considered in the path planning, like temporal constraints of the motion imposed by limits on the velocities and accelerations of the robots, or raising the tether's clearance. Simulated and field test results demonstrate that the approach generates obstacle-free, smooth, and feasible trajectories for the marsupial system.
Applications for carbon nanotubes (CNT) and the reuse of iron ore tailings (IOT) have been explored in the literature about nanostructured cementitious materials. Reinforced iron ore tailings (R-IOT) was produced growing CNT from an external catalyst directly on particles of IOT, regardless of its iron content. In this work, analyses by infrared spectroscopy detail the chemical bonds between IOT grains and the external catalyst. Also, different in situ CNT concentrations (0.05%, 0.2%, and 0.8%) in R-IOT were used for preparing a mortar which 25% of its aggregate’s composition is reused IOT. R-IOT increased flexural strength (up to 29% with 0.8% CNT) and delivered better reinforcement efficiency (up to 60%) when compared to functionalized CNT. The electrical conductivity of the nanostructured composites was also higher (up to 370%) when compared nanostructured mortar to the mortar prepared from plain IOT. Contrary to the chemical CNT functionalization process to dispersion, the use of R-IOT to produce mortar is an easy and simple process that does not require additives, admixtures, surfactants, or any other additional chemical procedure. In terms of circular economy, the process combines innovation and sustainability since it reinserts IOT in the productive flow, representing an efficient application for this residue of mining activities. Graphical abstract
Territorial species are unlikely to show extensive movements between breeding seasons. This is especially true for long-lived species, which often have strong pair bonding and can occupy the same territory for years. However, also in such species, individuals may face situations that can lead to a territory shift. Here, we use a comprehensive dataset documenting 40 years of breeding behavior in tawny owl (Strix aluco) – a long-lived species with high site tenacity and mate fidelity – to examine the factors affecting the decisions whether or not to move to another breeding territory and how far, as well as the fitness consequences thereof. We found that the likelihood and distance of movement in either sexes is strongly associated with a change of partner, indicating that mate loss may cause breeding dispersal. Moreover, mate change, not movement to a new territory, had negative effects on subsequent reproductive performance: individuals that changed partner were more likely to skip reproduction in the subsequent year and, in those cases they bred, they produced smaller clutches and raised fewer offspring. Our findings indicate that tawny owls change territory almost exclusively when searching for a new partner and that mate change has profound consequences on their subsequent breeding performance. Overall, our study provides evidence that in tawny owls territoriality and monogamy are associated and strongly linked to fitness, but mate fidelity may be more important than site fidelity, likely because sexes are involved in specific tasks and their cooperation ensures breeding success and, consequently, increases fitness. Significance statement Breeding dispersal, the movement of individuals between breeding sites, can entail high costs for animal fitness, especially for territorial species, which display strong site fidelity. We studied the factors associated with breeding dispersal and the consequences on breeding performances in tawny owl (Strix aluco), a highly territorial species. We found that tawny owls moved more frequently to another breeding territory when the mate died. Either sexes showed an equal probability to move, but the effect was stronger in females than in males after a mate change. Moreover, owls that changed partner showed delayed reproduction, smaller clutch and a higher probability to skip reproduction. Our findings show that in tawny owls territoriality and monogamy are associated and strongly linked to fitness, but mate fidelity may be more important than site fidelity, likely because sexes share the costs of holding the territory.
The article analyses the determinants of acquisition of flamenco albums. Flamenco is a musical genre recognized by UNESCO as intangible heritage of humanity. A methodology divided into three phases has been used for this purpose: firstly, interviews with experts from the Spanish music industry where new variables are identified that can affect flamenco consumption habits; then 586 surveys of flamenco spectators who valued these variables and, finally, the application of econometric models to obtain the coefficients of the variables. The results show how the valuation of the composition, the performer and its virtuosity, of the existing trends, and the sociodemographic characteristics of the spectators directly affect the acquisition of flamenco-recorded music. The article contributes to the scarce empirical literature that relates the determinants of recorded music acquisition with traditional popular genres, by adding never studied before variables, focusing on the case of flamenco. JEL Classification: C2; D2; Z1. MSC2010: 00A65; 00A66.
Abstract The green synthesis method was used to prepare SnO2 nanoparticles (NPs) from Laurus nobilis L. aqueous extract. Gelatin-based films are a promising substitute for traditional plastics due to their eco-friendliness, low cost, and pliability. However, they have some drawbacks such as high water solubility, poor opacity, and permeability to vapor. The use of synthesized SnO2 NPs can help address these concerns. The GEL/SnO2 film has enhanced morphological and physicochemical properties, with antibacterial properties that could extend the shelf life of perishable items like strawberries, contributing to reducing food waste. To improve their antibacterial activity, the SnO2 NPs were functionalized with the cefazolin (CEF) drug. The synthesized SnO2 NPs and the CEF@SnO2 nanocomposite (NC) were characterized using various techniques such as UV-vis, FTIR, SEM, and XRD. The results showed that the particle sizes of SnO2 NPs and CEF@SnO2 NC were 28 nm and 35 nm, respectively, and SEM analysis revealed spherical-shaped agglomerated particles for both. The optical bandgap energy was calculated to be 3.3 and 2.34 eV for SnO2 NPs and CEF@SnO2 NC, respectively. The antibacterial activity exhibits an excellent inhibition zone for synthesized SnO2 NPs and the CEF@SnO2 NC with different concentrations (1, 3, and 5 mM) against E.coli, P. aeruginosa, and S. aureus. CEF@SnO2 NC revealed a strong effect compared to SnO2 NPs, where 5 mM shows the highest inhabitation zone. Molecular docking studies supported the experimental data, indicating the interaction between proteins and the CEF@SnO2. This approach offers an innovative way of synthesizing drug-loaded SnO2 NPs as functional biomaterials.
In this paper we present a novel mathematical optimization-based methodology to construct tree-shaped classification rules for multiclass instances. Our approach consists of building Classification Trees in which, except for the leaf nodes, the labels are temporarily left out and grouped into two classes by means of a SVM separating hyperplane. We provide a Mixed Integer Non Linear Programming formulation for the problem and report the results of an extended battery of computational experiments to assess the performance of our proposal with respect to other benchmarking classification methods.
The realised ecological niches of species may change in response to dynamic abiotic and biotic environments, particularly under fast global change. To fully understand the dynamics of niche features and their drivers, it is essential to have a long‐term view of species distributions and the factors that may have influenced them. Here, we analysed the distribution and niche dynamics of the Italian crayfish ( Austropotamobius fulcisianus ) in the Iberian Peninsula over the past 200 years. The Italian crayfish was introduced to Spain in the 16th century, and spread due to multiple stocking events until the 1970s, when two North American crayfish (red swamp crayfish Procambarus clarkii , and signal crayfish Pacifastacus leniusculus ) were introduced. Both North American species are carriers of a pathogen ( Aphanomyces astaci , the causal agent of crayfish plague) lethal to the Italian crayfish. We hypothesised that the realised niche of the Italian crayfish, both in breadth and in position, has changed over time following changes in its range. The distribution of the Italian crayfish expanded from the mid‐19th century until the mid‐20th century, in association with an enlargement of its realised niched, mostly towards less abrupt and more coastal‐influenced areas. After the introduction of the North American crayfishes, the collapse of the Italian crayfish involved a niche shift towards rough terrains in mountain areas. North American crayfish have eventually occupied most of the Italian crayfish's niche space, with the few no‐coexistence areas being relegated to the most abrupt and high‐elevation territories. Our historical approach allowed us to document and understand the highly dynamic distribution and niche of the Italian crayfish in the presence of invader counterparts, and to explore the environmental conditions under which their coexistence is minimised.
We propose in this paper a new nonlinear mathematical model of an oscillating water column (OWC). The one-dimensional shallow water equations in the presence of this device are reformulated as a transmission problem related to the interaction between waves and a fixed partially immersed structure. By imposing the conservation of the total fluid-OWC energy in the non-damped scenario, we are able to derive a transmission condition that involves a time-dependent air pressure inside the chamber of the device, instead of a constant atmospheric pressure as in Bocchi et al. (ESAIM Proc Surv 70:68–83, 2021). We then show that the transmission problem can be reduced to a quasilinear hyperbolic initial boundary value problem with a semi-linear boundary condition determined by an ODE depending on the trace of the solution to the PDE at the boundary. Local well-posedness for general problems of this type is established via an iterative scheme by using linear estimates for the PDE and nonlinear estimates for the ODE.
Schizophrenia is a debilitating psychiatric disorder associated with a reduced fertility and decreased life expectancy, yet common predisposing variation substantially contributes to the onset of the disorder, which poses an evolutionary paradox. Previous research has suggested balanced selection, a mechanism by which schizophrenia risk alleles could also provide advantages under certain environments, as a reliable explanation. However, recent studies have shown strong evidence against a positive selection of predisposing loci. Furthermore, evolutionary pressures on schizophrenia risk alleles could have changed throughout human history as new environments emerged. Here in this study, we used 1000 Genomes Project data to explore the relationship between schizophrenia predisposing loci and recent natural selection (RNS) signatures after the human diaspora out of Africa around 100,000 years ago on a genome-wide scale. We found evidence for significant enrichment of RNS markers in derived alleles arisen during human evolution conferring protection to schizophrenia. Moreover, both partitioned heritability and gene set enrichment analyses of mapped genes from schizophrenia predisposing loci subject to RNS revealed a lower involvement in brain and neuronal related functions compared to those not subject to RNS. Taken together, our results suggest non-antagonistic pleiotropy as a likely mechanism behind RNS that could explain the persistence of schizophrenia common predisposing variation in human populations due to its association to other non-psychiatric phenotypes.
AstroDART is a Python package that implements a pipeline for processing, analyzing, and managing files derived from observations performed by ground-based optical telescopes. The main goal is to develop a software capable of retrieving information about satellites’ tracklets. In between its functionalities the following are included: perform astrometric reduction using Astrometry.net, detect tracklets using contour tracing techniques with ASTRiDE Python Package, refine the detected tracklets and perform telescope calibration by comparing the observations of known objects with catalogue data and obtaining the celestial coordinates of the object at the observation epoch. In addition, it produces the light curve and TDM files derived from the observations. The computation times are in the order of 15 s per image when no astrometric reduction is performed, increased to 50 s when the astrometric reduction and light curve analysis are included. The average residuals for both right ascension and declination are found to be lower than 9 arcsecs for all of the three test campaigns.
Bovine tuberculosis is considered a re-emerging disease caused by different species from the Mycobacterium tuberculosis complex (MTC), important not only for the livestock sector but also for public health due to its zoonotic character. Despite the numerous efforts that have been carried out to improve the performance of the current antemortem diagnostic procedures, nowadays, they still pose several drawbacks, such as moderate to low sensitivity, highlighting the necessity to develop alternative and innovative tools to complement control and surveillance frameworks. Volatilome analysis is considered an innovative approach which has been widely employed in animal science, including animal health field and diagnosis, due to the useful and interesting information provided by volatile metabolites. Therefore, this study assesses the potential of gas chromatography coupled to ion mobility spectrometry (GC-IMS) to discriminate cattle naturally infected (field infections) by MTC from non-infected animals. Volatile organic compounds (VOCs) produced from feces were analyzed, employing the subsequent information through chemometrics. After the evaluation of variable importance for the projection of compounds, the final discriminant models achieved a robust performance in cross-validation, as well as high percentages of correct classification (>90%) and optimal data of sensitivity (91.66%) and specificity (99.99%) in external validation. The tentative identification of some VOCs revealed some coincidences with previous studies, although potential new compounds associated with the discrimination of infected and non-infected subjects were also addressed. These results provide strong evidence that a volatilome analysis of feces through GC-IMS coupled to chemometrics could become a valuable methodology to discriminate the infection by MTC in cattle. IMPORTANCE Bovine tuberculosis is endemic in many countries worldwide and poses important concerns for public health because of their zoonotic condition. However, current diagnostic techniques present several hurdles, such as low sensitivity and complexity, among others. In this regard, the development of new approaches to improve the diagnosis and control of this disease is considered crucial. Volatile organic compounds are small molecular mass metabolites which compose volatilome, whose analysis has been widely employed with success in different areas of animal science including animal health. The present study seeks to evaluate the combination of fecal volatilome analysis with chemometrics to detect field infections by bovine tuberculosis ( Mycobacterium tuberculosis complex) in cattle. The good robust performance of discriminant models as well as the optimal data of sensitivity and specificity achieved highlight volatilome analysis as an innovative approach with huge potential.
O Programa Farmácia Viva (FV) foi planejado com o objetivo de produzir fitoterápicos de qualidade com garantia de segurança e eficácia a partir de plantas medicinais validadas, buscando oferecer uma opção terapêutica, além de desenvolver trabalhos educativos sobre o uso correto de plantas medicinais. Este artigo tem por objetivo descrever a implantação de projeto piloto de FV na Unidade de Saúde da Família (USF) de Araraquara, com a finalidade de oferecer a fitoterapia como recurso terapêutico, promovendo o uso racional de plantas medicinais na Atenção Primária à Saúde (APS), resgatando o saber popular e baseado no conhecimento científico. Foi realizado um levantamento das principais doenças que acometem a população local e, a partir daí, foram selecionadas as plantas medicinais do projeto. Posteriormente iniciou-se o preparo do terreno para cultivo das mudas. Concomitantemente, foram realizadas rodas de conversa, cursos e oficinas com a comunidade e a equipe de saúde da USF sobre preparo de mudas e uso racional de plantas medicinais. Os resultados mostraram que ansiedade, problemas respiratórios, gástricos e inflamação são as patologias que mais acometem a população local. As seguintes espécies foram selecionadas para serem cultivadas: Curcuma longa (cúrcuma), Cymbopogon citratus (capim limão), Lippia alba (lípia), Maytenus ilicifolia (espinheira santa), Mikania glomerata (guaco) e Plectrantus barbatus (boldo nacional), seguindo o Formulário Fitoterápico da Farmacopeia Brasileira. As rodas de conversa, oficinas e cursos possibilitaram à comunidade e equipe de saúde local o acesso às informações científicas, em linguagem simples, valorizando trocas de experiências, descrevendo as plantas medicinais, suas propriedades terapêuticas, forma de preparo, dosagem e contraindicações. As oficinas de chá permitiram aos participantes resgatar a memória afetiva da família, fator importante para o sucesso do projeto FV. A FV é um projeto social que tem demonstrado resgatar a autoestima da comunidade e a capacidade de orientar o uso racional de plantas medicinais, valorizando a fitoterapia como recurso terapêutico de escolha no sistema de saúde.
Bacterial SOS response is an inducible system of DNA repair and mutagenesis. Streptococci lack a canonical SOS response, but an SOS-like response was reported in some species. The mef (A)- msr (D)-carrying prophage Ф1207.3 of Streptococcus pyogenes contains a region, spanning orf6 to orf11 , showing homology to characterized streptococcal SOS-like cassettes. Genome-wide homology search showed the presence of the whole Φ1207.3 SOS-like cassette in three S . pyogenes prophages, while parts of it were found in other bacterial species. To investigate whether this cassette confers an SOS-mutagenesis phenotype, we constructed Streptococcus pneumoniae R6 isogenic derivative strains: (i) FR172, streptomycin resistant, (ii) FR173, carrying Φ1207.3, and (iii) FR174, carrying a recombinant Φ1207.3, where the SOS-like cassette was deleted. These strains were used in survival and mutation rate assays using a UV-C LED instrument, for which we designed and 3D-printed a customized equipment, constituted of an instrument support and swappable-autoclavable mini-plates and lids. Upon exposure to UV fluences ranging from 0 to 6,400 J/m ² at four different wavelengths, 255, 265, 275, and 285 nm, we found that the presence of Φ1207.3 SOS-like cassette increases bacterial survival up to 34-fold. Mutation rate was determined by measuring rifampicin resistance acquisition upon exposure to UV fluence of 50 J/m ² at the four wavelengths by fluctuation test. The presence of Φ1207.3 SOS-like cassette resulted in a significant increase in the mutation rate (up to 18-fold) at every wavelength. In conclusion, we demonstrated that Φ1207.3 carries a functional SOS-like cassette responsible for an increased survival and increased mutation rate in S. pneumoniae . IMPORTANCE Bacterial mutation rate is generally low, but stress conditions and DNA damage can induce stress response systems, which allow for improved survival and continuous replication. The SOS response is a DNA repair mechanism activated by some bacteria in response to stressful conditions, which leads to a temporary hypermutable phenotype and is usually absent in streptococcal genomes. Here, using a reproducible and controlled UV irradiation system, we demonstrated that the SOS-like gene cassette of prophage Φ1207.3 is functional, responsible for a temporary hypermutable phenotype, and enhances bacterial survival to UV irradiation. Prophage Φ1207.3 also carries erythromycin resistance genes and can lysogenize different pathogenic bacteria, constituting an example of a mobile genetic element which can confer multiple phenotypes to its host.
Gut microbiota plays a crucial role in regulating the response to immune checkpoint therapy, therefore modulation of the microbiome with bioactive molecules like carotenoids might be a very effective strategy to reduce the risk of chronic diseases. This review highlights the bio-functional effect of carotenoids on Gut Microbiota modulation based on a bibliographic search of the different databases. The methodology given in the preferred reporting items for systematic reviews and meta-analyses (PRISMA) has been employed for developing this review using papers published over two decades considering keywords related to carotenoids and gut microbiota. Moreover, studies related to the health-promoting properties of carotenoids and their utilization in the modulation of gut microbiota have been presented. Results showed that there can be quantitative changes in intestinal bacteria as a function of the type of carotenoid. Due to the dependency on several factors, gut microbiota continues to be a broad and complex study subject. Carotenoids are promising in the modulation of Gut Microbiota, which favored the appearance of beneficial bacteria, resulting in the protection of villi and intestinal permeability. In conclusion, it can be stated that carotenoids may help to protect the integrity of the intestinal epithelium from pathogens and activate immune cells.
Background Many patients with depression refuse treatment. Moreover, suicide attempters often display low perceived need of treatment and impaired decision-making. These observations raise questions about the capacity to treatment consent in depressed suicide attempters (SA). Methods In patients with current depressive episode ( N = 33 SAs and N = 27 non-SAs), consent capacity was evaluated with the MacArthur Competence Assessment Tool for Treatment (MacCAT-T), insight with the Beck Cognitive Insight Scale, and depression severity with the Beck Depression Inventory (BDI). Results The median BDI score in the whole sample ( N = 60) was 21 [10;36], and was higher in SAs than non-SAs (27 [11;36] vs. 15 [10:33], p < 0.001). Consent capacity was impaired in 30% (appreciation), 53% (reasoning) and 60% (understanding) of all patients. MacCAT-T sub-scores were lower in SAs than non-SAs (understanding: 4.4 [2.35;5.8] vs. 5.3 [3.13;6]); appreciation: 3 [1;4] vs. 4 [2;4]); reasoning (4 [1;7] vs. 7 [3;8]), and ability to express a choice: 1 [0;2] vs. 2 [0;2]; all p < 0.001). In multivariate analyses, suicide attempt history and depression severity (but not insight) were negatively associated with MacCAT-T sub-scores. Conclusion More research is needed on the capacity to consent to treatment of patients with depression, particularly suicidal individuals, to make informed choices about their treatment. Trial registration The Montpellier University Hospital Institutional Review Board approved the study (No. 202100714).
The well-suited discretization of the Keller–Segel equations for chemotaxis has become a very challenging problem due to the convective nature inherent to them. This paper aims to introduce a new upwind, mass-conservative, positive and energy-dissipative discontinuous Galerkin scheme for the Keller–Segel model. This approach is based on the gradient-flow structure of the equations. In addition, we show some numerical experiments in accordance with the aforementioned properties of the discretization. The numerical results obtained emphasize the really good behaviour of the approximation in the case of chemotactic collapse, where very steep gradients appear.
Dehesas are Mediterranean agro-sylvo-pastoral systems sensitive to climate change. Extreme climate conditions forecasted for Mediterranean areas may change soil C turnover, which is of relevance for soil biogeochemistry modeling. The effect of climate change on soil organic matter (SOM) is investigated in a field experiment mimicking environmental conditions of global change scenarios (soil temperature increase, +2-3 °C, W; rainfall exclusion, 30%, D; a combination of both, W+D). Pyrolysis-compound-specific isotope analysis (Py-CSIA) is used for C and H isotope characterization of SOM compounds and to forecast trends exerted by the induced climate shift. After 2.5 years, significant δ13C and δ2H isotopic enrichments were detected. Observed short- and mid-chain n-alkane δ13C shifts point to an increased microbial SOM reworking in the W treatment; a 2H enrichment of up to 40‰ of lignin methoxyphenols was found when combining W+D treatments under the tree canopy, probably related to H fractionation due to increased soil water evapotranspiration. Our findings indicate that the effect of the tree canopy drives SOM dynamics in dehesas and that, in the short term, foreseen climate change scenarios will exert changes in the SOM dynamics comprising the biogeochemical C and H cycles.
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11,613 members
David Leon
  • Plant Biology and Ecology
Manuel Pérez-Ruiz
  • Aerospace Engineering and Fluid Mechanics
Isidoro Caraballo
  • Pharmacy and Pharmaceutical Technology
C/ San Fernando, 4, 41004, Sevilla, Spain
Head of institution
Miguel Ángel Castro Arroyo