Universidad Pablo de Olavide
  • Sevilla, Andalucia, Spain
Recent publications
Over the last decade, the use of different artificial intelligence (AI) tools has increased. To shed some light on the emerging trend of AI disclosure, the aim of this paper is to analyse the current practices of major Western European companies regarding the automated decision-making (ADM) disclosure in their annual or sustainability reports. This paper proposes a methodology based on bigrams that enables the automatic extraction of the information on ADM that companies disclose. The sample consisted of 962 annual/sustainability reports, published in 2018 and 2019, of 337 companies listed on 13 Western European countries’ stock markets. Our findings show that ADM disclosure is still at an early stage and that the first adopters are mostly companies operating in the financial sector.
Feature selection is becoming more and more a challenging task due to the increase of the dimensionality of the data. The complexity of the interactions among features and the size of the search space make it unfeasible to find the optimal subset of features. In order to reduce the search space, feature grouping has arisen as an approach that allows to cluster feature according to the shared information about the class. On the other hand, metaheuristic algorithms have proven to achieve sub-optimal solutions within a reasonable time. In this work we propose a Scatter Search (SS) strategy that uses feature grouping to generate an initial population comprised of diverse and high quality solutions. Solutions are then evolved by applying random mechanisms in combination with the feature group structure, with the objective of maintaining during the search a population of good and, at the same time, as diverse as possible solutions. Not only does the proposed strategy provide the best subset of features found but it also reduces the redundancy structure of the data. We test the strategy on high dimensional data from biomedical and text-mining domains. The results are compared with those obtained by other adaptations of SS and other popular strategies. Results show that the proposed strategy can find, on average, the smallest subsets of features without degrading the performance of the classifier.
Floodplain forests are sensitive to climate warming and increased drought, as showed by recent oak (Quercus robur) dieback and mortality episodes. However, a comprehensive comparison of coexisting tree species under different climate settings or biomes are lacking. Herein, we compared growth rates, growth responses to climate and drought severity, and modeled climate mediated growth of oak and three coexisting tree species (ash, Fraxinus angustifolia; alder, Alnus glutinosa; elm, Ulmus minor). Two floodplain forests subjected to cooler (temperate climate, Ticino) and warmer (Mediterranean climate, Bosco Pantano) conditions in northern and southern Italy, respectively, were analyzed. Ash seemed to be the most sensitive to drought, particularly at the Mediterranean site where oak and elm growth were also negatively affected by water shortages. Alder appeared to be the least sensitive species in terms of growth variability to drought under both temperate and Mediterranean climate conditions. Furthermore, the growth model revealed the influence of soil moisture in spring and summer on the constrained growth of ash and oak and illustrated how oak growth could be severely reduced during drastic hotter droughts. Alder seemed to be the most drought-resistant species under both environmental conditions. These results could represent the first attempts in documenting the ecological consequences of drought in terms of projected climate trends in less investigated Mediterranean floodplain forests. Furthermore, these results highlight how climate and tree-ring data combined with growth models could be useful tools to detect early warning signals of growth decline and impending dieback in floodplain forests in response to dry spells.
The growing processes of the socioeconomic inequality resulting from the neoliberal political model are evident in large Spanish cities, with a spatial dimension that allows us to visualise its contradictions with great clarity. These social contradictions are particularly marked among the most vulnerable and foreign population groups. For this reason, the study of the spaces and services termed Social Infrastructures (SI), as facilities which favour social integration and cohesion in the city, is of special importance. Our study addresses the distribution of SI in the Spanish cities of Madrid and Barcelona, their relationship with the level of vulnerability in the neighbourhoods and the distribution of the Spanish and foreign population in a novel way, by creating a synthetic SI index and using a non-hierarchical clustering method. Our results show two completely different city models: in Barcelona, SI are distributed following the criterion of socio-territorial equity, while in Madrid, there is a greater presence of SI in the wealthier areas. This leads us to reflect on the social and political implications of our results in both cities.
Soil salinization is a widespread environmental problem adversely impacting global food production. Increasing soil organic matter (SOM) could alleviate salt stress, but soil salinity and SOM have differing effects on microbial diversity and activities. We explored how the relationships between soil biodiversity and multifunctionality were altered by soil salinity and SOM. We collected soils from the wheat-maize cropping system in the North China Plain and categorized soils according to salinity and SOM. Soil functions related to carbon, nitrogen, phosphorus, and micronutrient processing were measured as metrics of soil multifunctionality (SMF) characterization. We found significant positive relationships between SMF and bacterial diversity but not fungal diversity in soils with high SOM (>15 mg/kg) and low EC (<4 ds/m). The diversity and abundance of sensitive bacteria were more strongly correlated with SMF than those of non-sensitive bacteria. SOM directly and indirectly impacted SMF through changes in sensitive bacterial abundance, while soil EC impacted SMF via altered sensitive bacterial diversity. With respective to individual soil function, carbon and micronutrient cycling were predominantly determined by bacterial diversity. Our findings suggest coupling decreased salinization with the increase of SOM could increase soil multifunctionality by increasing diversity and abundance of sensitive soil microbes. These findings highlight the importance of sensitive microbial taxa to sustaining soil ecosystem functioning in croplands.
Cholesterol and the immune system are involved in Alzheimer's Disease (AD). To investigate the relations among them, we compared the cholesterol content in peripheral blood mononuclear cells (PBMC) of cognitively healthy controls and patients with mild cognitive impairment (MCI) and AD in two independent samples. Free cholesterol content of PBMC was lower in MCI and AD patients, and was modulated by APOE genotype. A decrease of CD8+ and an increase of CD16+ was also found in AD patients. These results suggest that cholesterol levels in PBMCs may represent an early signature of the disease and support the involvement of immune system in AD.
Fermentation of orange juice (OJ) by Pichia kluyveri enhances the content of melatonin, a molecule with potent antioxidant effect. This study explores the levels of urine 6- sulfatoxymelatonin (6-SMT) in healthy subjects after fermented orange juice (FOJ) intake, and their association with antioxidant activity status. Nine participants ingested 500 mL of FOJ and their urine was collected at baseline and after 2, 5, 10, 15 and 24 h. After a two-week washout period, the intervention was repeated with OJ. 6-SMT levels were quantified by ELISA and antioxidant activity by TAC, FRAP and ORAC assays. A significant increase in both 6-SMT levels and antioxidant activity in urine was observed after FOJ ingestion compared to OJ. A positive correlation between TAC and 6-SMT levels was observed only after FOJ intake. This study shows for the first time that fermentation process increases melatonin bioavailability of OJ associated with an enhancement in antioxidant status.
Although most arcuate orogens are deformed as progressive arcs—curvature is acquired during shortening‐, they have been scarcely simulated by analog modeling. To investigate factors that control the growth of progressive curves in fold‐and‐thrust belts, we developed seven analog models where the backstop shape changed over time, and distinctive geometric heterogeneities were set in the detachment layer. These heterogeneities, often described in natural cases, include diapirs, thickness lateral variations (including pinch‐outs) of the viscous detachment layer as well as frontal pinch‐outs. Our results show that strain was partitioned between shortening structures showing radial transport directions, and both normal and oblique strike‐slip faults that accommodated arc‐lengthening. The location of any heterogeneity conditioned the nucleation of structures and thus, the wedge evolution and its resulting geometry. The presence of both diapirs and frontal silicone pinch‐outs favored the stagnation of the deformation front, and the subsequent wedge thickening up to reach the supercritical angle. Both diapirs and thickness lateral variations of the viscous layer localized arc‐parallel stretching. In addition, their configuration determined the amount and distribution of salients and recesses along the arcuate belt, diapirs and more frictional detachments favoring thicker wedges and less frontal propagation. The differential displacement between salients and recesses was accommodated by strongly partitioned transfer zones, localized by the boundaries between distinctive detachment domains. These results may be useful to investigate geometric and kinematic changes along natural progressive arcs such as the Gibraltar, Sulaiman and Zagros cases.
Organic livestock farming can help to make agroecosystems more sustainable. We hypothesized, however, that not all organic farm management models contribute in the same way. One way to assess this is to perform energy analyses of livestock farms, establishing not only how efficient the systems are at producing goods and services for society, but also the investment in the fund elements that sustain the system itself and its environmental sustainability. But to be effective, such studies must go beyond a classic input-output analysis: they must also address the internal energy flows that maintain the quality of agroecosystem fund elements as well as some ecosystem services they provide. In the present work, we implemented the energy return on investment methodology and combined classic economic energy indicators with new agroecological measurements that allow to assess the quality of agroecosystem fund elements. We applied these agroecological energy indicators to organic pig and beef cattle farms with the aim of differentiating the organic forms of management that best contribute to sustainability. This is the first time that this methodology has been applied on pig farms. Based on this methodology, we identified five management models of organic beef and pork production in Mediterranean systems that presented different degrees of sustainability. The most efficient and environmentally sustainable model was the breeding of beef cattle/pigs in agrosilvopastoral dehesa pasturelands. These dehesa systems include farms that are highly self-sufficient in terms of animal feed as well as farms that import certain feed stuffs because they fatten animals until slaughter. It was the breed together with the stocking densities that conditioned livestock functionality more than the livestock species orientation. The results allowed us to distinguish the various forms of organic livestock management implemented and their degree of sustainability, thus providing public policy orientations on the most efficient models. https://rdcu.be/c0ilQ
Abstract Homonota taragui is an endemic gecko of the northeast of Argentina. We estimate demographic parameters: number of individuals by populations, sex and ontogenetic stage; sexual dimorphism; survival of this species; and describe the use of microhabitat and movement patterns. We measured 11 morphological variables, determined the sex and marked individually. We found bigger head width in males. Some factors contribute to the vulnerability of this species such as its constrained geographical distribution, use of the specific microhabitat and the isolation of their populations. We highlight demography studies as an essential data source for management and conservation of critically endangered species.
Fungi are major drivers of ecosystem functioning. Increases in aridity are known to negatively impact fungal community composition in dryland ecosystems globally; yet, much less is known on the potential influence of other environmental drivers, and whether these relationships are linear or nonlinear. 2017–2021. Global. Fungi. We re‐analysed multiple datasets from different dryland biogeographical regions, for a total of 912 samples and 1,483 taxa. We examined geographical patterns in community diversity and composition, and spatial, edaphic and climatic factors driving them. UV index, climate seasonality, and sand content were the most important environmental predictors of community shifts, showing the strongest association with the richness of putative plant pathogens and saprobes. Important nonlinear relationships existed with each of these fungal guilds, with increases in UV and temperature seasonality above 7.5 and 900 SD (standard deviation x 100 of the mean monthly temperature), respectively, being associated with an increased probability of plant pathogen and unspecified saprotroph occurrence. Conversely, these environmental parameters had a negative relationship with litter and soil saprotroph richness. Consequently, these ecological groups might be particularly sensitive to shifts in UV radiation and climate seasonality, which is likely to disturb current plant–soil dynamics in drylands. Our synthesis integrates fungal community data from drylands across the globe, allowing the investigation of fungal distribution and providing the first evidence of shifts in fungal diversity and composition of key fungal ecological groups along diverse spatial, climatic and edaphic gradients in these widely distributed ecosystems. Our findings imply that shifts in soil structure and seasonal climatic patterns induced by global change will have disproportionate consequences for the distribution of fungal groups linked to vegetation and biogeochemical cycling in drylands, with implications for plant–soil interactions in drylands.
Purpose Weight self-stigma may be defined as a self-devaluation due to one’s identification with the group of people with obesity. The Weight Self-Stigma Questionnaire (WSSQ) is an instrument specifically designed to measure weight self-stigma in populations with overweight or obesity. The objective of this study was to adapt the WSSQ to the Spanish population (S-WSSQ) following the guidelines for cross-cultural adaptations. Methods The sample comprised 165 participants with obesity seeking weight loss treatment (65% women) at the “ Hospital de Valme ” (Seville, Spain). Scales to measure life satisfaction, self-esteem, positive and negative affect, and antifat attitudes were used to analyze the convergent and divergent validity of the S-WSSQ. Results A confirmatory factor analysis showed adequate values of the goodness of fit indexes of a two-factor model ( χ ² /df = 2.01 CFI = 0.92, IFI = 0.92, SRMR = 0.08, RMSEA = 0.078), replicating the structure found by the original authors. Cronbach’s alphas of the two factors were 0.76 (self-devaluation) and 0.77 (fear of enacted stigma). Composite Reliability values were 0.72 (self-devaluation) and 0.76 (fear of enacted stigma). Self-devaluation and fear of enacted stigma were negatively related to self-esteem, and positive affect, and positively related to negative affect and antifat attitudes. Finally, life satisfaction was negatively correlated to fear of enacted stigma. Conclusions Based on these results, it is concluded that the S-WSSQ has good psychometric properties and might be used by the Spanish-speaking scientific community to measure weight self-stigma. Level of evidence Level V, descriptive study.
We demostrate for the first time the potential of zeolitic-imidazolate framework-8 nanoparticles to be incorporated within a renal scaffold while retaining their ability to remove uremic toxins (mainly hydrophobic toxins...
Studying current and future geographic distribution is essential for conserving endangered species such as the Boreal Owl and Eurasian Pygmy Owl. The main aim of this study was to determine the potential distribution of both species in the Balkan Peninsula by using spatial distribution models (SDMs) in MaxEnt. We used data from field surveys, the scientific and grey literature, and an online database. We considered the current time and two future periods, 2041–2060 and 2061–2080. For future periods, we included different climate scenarios (SSP 126, 245, 370, and 585) in studying the potential geographic distribution of both species. We identified two types of potential future refugia for species: in situ and ex situ. Our study shows the highly suitable area for the Boreal Owl increased during the 2041–2060 period compared with the current area in all scenarios, except in SSP 585. However, during the 2061–2080 period, the highly suitable areas contracted. For the Eurasian Pygmy Owl, highly suitable areas decreased during 2041–2060, but during the 2061–2080 period, it was larger than the current area. Our study is of importance for conservation and preserving areas of potential distribution and refugia for Boreal and Eurasian Pygmy Owls in the face of climate change.
We study an air-fluidized granular monolayer composed of plastic spheres which roll on a metallic grid. The air current is adjusted so that the spheres never lose contact with the grid and so that the dynamics may be regarded as pseudo two dimensional (or two dimensional, if the effects of the sphere rolling are not taken into account). We find two surprising continuous transitions, both of them displaying two coexisting phases. Moreover, in all the cases, we found the coexisting phases display a strong energy non-equipartition. In the first transition, at a weak fluidization, a glass phase coexists with a disordered fluid-like phase. In the second transition, a hexagonal crystal coexists with the fluid phase. We analyze, for these two-phase systems, the specific diffusive properties of each phase, as well as the velocity correlations. Surprisingly, we find a glass phase at a very low packing fraction and for a wide range of granular temperatures. Both phases are also characterized by strong anticorrelated velocities upon a collision. Thus, the dynamics observed for this quasi two-dimensional system unveil phase transitions with peculiar properties, very different from the predicted behavior in well-know theories for their equilibrium counterparts.
Background Amphioxus are non-vertebrate chordates characterized by a slow morphological and molecular evolution. They share the basic chordate body-plan and genome organization with vertebrates but lack their 2R whole-genome duplications and their developmental complexity. For these reasons, amphioxus are frequently used as an outgroup to study vertebrate genome evolution and Evo-Devo. Aside from whole-genome duplications, genes continuously duplicate on a smaller scale. Small-scale duplicated genes can be found in both amphioxus and vertebrate genomes, while only the vertebrate genomes have duplicated genes product of their 2R whole-genome duplications. Here, we explore the history of small-scale gene duplications in the amphioxus lineage and compare it to small- and large-scale gene duplication history in vertebrates. Results We present a study of the European amphioxus (Branchiostoma lanceolatum) gene duplications thanks to a new, high-quality genome reference. We find that, despite its overall slow molecular evolution, the amphioxus lineage has had a history of small-scale duplications similar to the one observed in vertebrates. We find parallel gene duplication profiles between amphioxus and vertebrates and conserved functional constraints in gene duplication. Moreover, amphioxus gene duplicates show levels of expression and patterns of functional specialization similar to the ones observed in vertebrate duplicated genes. We also find strong conservation of gene synteny between two distant amphioxus species, B. lanceolatum and B. floridae, with two major chromosomal rearrangements. Conclusions In contrast to their slower molecular and morphological evolution, amphioxus’ small-scale gene duplication history resembles that of the vertebrate lineage both in quantitative and in functional terms.
Structural determination of protein assemblies in their native environment is essential to understand the molecular mechanisms that regulate cellular processes. This is crucial for basic research in cell biology, but it also impacts other fields such as protein engineering and drug development. However, technical constraints prevent resolving structural details at high resolution directly in the cell, whereas in vitro methods are limited to study protein complexes withdrawn from their functional context. Fundamental insight such as structural dynamics that mediate proteins' function remains largely unexplored. The challenge relies on determining the physiological architecture and dynamism of cellular molecules at high resolution. This chapter presents an overview of the dominant techniques for the structural determination of molecular assemblies and the main limitations of these methods. We highlight the importance of recent integrative approaches that overcome current technical barriers and provide detailed insights into the structure of protein complexes and their function in the native environment. As an example, we provide the practical case of the exocyst complex, a conserved multimer that is indispensable in exocytosis. Advanced imaging nanotools and integrative modeling worked together to resolve exocyst structural switches during exocytosis. This example demonstrates the potential of introducing live‐cell imaging within integrative structural biology to derive mechanistic insights, pushing the limits found in individual techniques. We finish the chapter with a discussion on future directions of integrative structural biology and some approaches that can complement existing strategies to transform the field of structural cell biology.
We examine the impact of employees' perceptions of management control systems (MCS) as a threat on two forms of misconduct: deliberate ignorance and workplace deviance. Drawing on the theory of cognitive dissonance, we predict that a perceived threat is associated with a decrease in workplace deviance but may also trigger unintended consequences, such as deliberate ignorance. Hypotheses are tested using survey data from three large hospitals. Taken together, our results suggest that employees' perceptions of MCS as a threat have (1) a negative curvilinear effect on workplace deviance and (2) a positive linear association with deliberate ignorance. Additionally, we find that the need for professional autonomy shapes the effect of employees' perception of MCS as a threat on both forms of misconduct. Overall, by providing new empirical evidence on how employees perceive MCS and their (un)intended consequences, we add to the growing body of research on the effects of control systems on employees' behaviour.
Playa‐lakes developed in closed watersheds have been used as environmental impacts indicators (global warming, water extractions...), but they could be also sensitive to active tectonics. . Our study area is located in the main watershed in the western Betics, the northern branch of the Gibraltar arc, which is within the fold‐and‐thrust belt. This area is characterized by an endorheic zone that includes some playa‐lakes floored by low‐permeable rocks. Our study shows the reduction or disappearance of playa‐lake flooded surfaces due to the reduction of their watershed area. This area reduction is favoured by stream catchments related to knick‐points, which seem to be generated by the quaternary activity of a dextral‐transpressive band within the Betics fold‐and‐thrust belt. χ map also shows the higher erosion power of Mediterranean streams, which will likely catch this endorheic area in tectonics quiescence.
Aim: Palaeoclimate legacies have been reported to influence microbial communities and carbon (C) stocks even after thousands of years. However, the direct and indirect influences of climate legacies on microbial C processes remain poorly understood and thus limit our capacity to predict how climate legacies regulate C cycling. Here, we conducted microbial, soil and vegetation surveys along a continental latitudinal tran-sect of 4200 km covering a wide range of forest biomes. With these data, we evaluated the potential capacity of climate legacies to predict direct and indirect variations in microbial metabolic quotient (MMQ) across and within three main forest biomes: tropical, subtropical and temperate forests. Location: North-south transect (4200 km), China. Time period: 2019. Major taxa studied: Soil microbes. Methods: We used molecular ecology technology to determine microbial biomass and diversity, in addition to a soil incubation experiment to measure MMQ. Results: Palaeoclimate explained a unique portion of the variation in the continental distribution of MMQ, which showed a hump-shaped pattern with latitude. Locations with increased isothermality (an index of temperature) over the last 20,000 years also showed the highest MMQ in the present day. Moreover, we found multiple indirect effects of climate legacies on MMQ caused either by changes in key soil properties, such as soil organic carbon and ammonium (NH 4 +), in lower latitudinal regions or by plant traits in higher latitudinal regions. Furthermore, MMQ was positively related to bacterial richness but negatively to fungal richness across forest biomes.
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2,935 members
Martina Carrete
  • Department of Physical, Chemical and Natural Systems
David Cobos Sanchiz
  • Fac. Ciencias Sociales
Yolanda Rebollo
  • Economic Analysis
Juan Antonio Prieto Velasco
  • Department of Philology and Translation
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Address
Ctra. Utrera km. 1, 41013, Sevilla, Andalucia, Spain
Head of institution
Universidad Pablo de Olavide
Website
www.upo.es