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Cardiac and neurobehavioral impairments in three phylogenetically distant aquatic model organisms exposed to environmentally relevant concentrations of boscalid
Get PDFBoscalid (2-Chloro-N-(4′-chlorobiphenyl-2-yl) nicotinamide), a pyridine carboxamide fungicide, is an inhibitor of the complex II of the respiration chain in fungal mitochondria. As boscalid is only moderately toxic for aquatic organisms (LC50 > 1–10 mg/L), current environmental levels of this compound in aquatic ecosystems, in the range of ng/L-μg/L, are considered safe for aquatic organisms. In this study, we have exposed zebrafish (Danio rerio), Japanese medaka (Oryzias latipes) and Daphnia magna to a range of concentrations of boscalid (1–1000 μg/L) for 24 h, and the effects on heart rate (HR), basal locomotor activity (BLA), visual motor response (VMR), startle response (SR), and habituation (HB) to a series of vibrational or light stimuli have been evaluated. Moreover, changes in the profile of the main neurotransmitters have been determined. Boscalid altered HR in a concentration-dependent manner, leading to a positive or negative chronotropic effect in fish and D. magna, respectively. While boscalid decreased BLA and increased VMR in Daphnia, these behaviors were not altered in fish. For SR and HB, the response was more species- and concentration-specific, with Daphnia exhibiting the highest sensitivity. At the neurotransmission level, boscalid exposure decreased the levels of L-aspartic acid in fish larvae and increased the levels of dopaminergic metabolites in D. magna. Our study demonstrates that exposure to environmental levels of boscalid alters cardiac activity, impairs ecologically relevant behaviors, and leads to changes in different neurotransmitter systems in phylogenetically distinct vertebrate and invertebrate models. Thus, the results presented emphasize the need to review the current regulation of this fungicide.info:eu-repo/semantics/publishedVersio
Unpacking Stimuli and Barriers to Internationalization Across Export Stages: The Case of Spanish Wine Firms in China
Get PDFFirm internationalization has been analyzed from different angles based on various theories. However, qualitative research on the stability of the factors that motivate and hinder internationalization across the export stages in emerging markets is limited. This study builds on the “stages” theories of internationalization, providing a detailed analysis of the perceived stability of stimuli and barriers during the exploration, entry, and expansion stages. We focus on a sample of Spanish wine firms exporting to China—a key wine market, with annual growth rates of over 25% between 2000 and 2020. The results suggest that the perception of most barriers is stage-dependent, varying over time as commitment levels evolve. The main stimuli, on the other hand, remain constant across the different export stages. Moreover, we find that firm size, international experience, and access to local and international networks are key factors that influence the evolution of firms' internationalization in China, while lateral rigidity continues to constrain the expansion of smaller companies. These findings contribute to a deeper understanding of the opportunities and challenges of doing business in an emerging market, particularly in the institutional context in China, as well as their evolution over different stages of internationalization. Furthermore, they offer insights into the dynamics of the Chinese wine market and the implications for European exporters.info:eu-repo/semantics/publishedVersio
Comunicación en la Universidad en tiempos de pandemia: impacto de la COVID-19 en los estudiantes
Get PDFLa investigación analiza la comunicación que se ha dado en la Universidad durante las primeras semanas de confinamiento derivado de la crisis del COVID-19 en España, así como la repercusión de la situación en las actividades académicas. Se ha seguido una metodología mixta mediante una encuesta ad hoc con escala likert además de focus groups con estudiantes de universidades presenciales y online. La investigación está basada en estudiantes de Educación Social de Barcelona (España). Los estudiantes confirman la dificultad para seguir adecuadamente sus estudios universitarios y dan importancia a los mensajes que la Universidad formulaba durante la situación de la crisis, aunque no fueran con decisiones totalmente cerradas. También admiten ciertas mejoras organizativas después de las primeras semanas de confinamiento. Los resultados pueden ayudar a mejorar la gestión de crisis similares que se den en el ámbito universitario.info:eu-repo/semantics/publishedVersio
Analysis of the centre of pressure in bipedal stance among individuals with and without intellectual disabilities, individuals with Down syndrome and dancers with Down syndrome
Get PDFBackground :
Individuals with intellectual disabilities (IDs) often present deficiencies in motor, balance and postural control. On the other hand, the practice of physical activity and dance usually reduces these deficiencies. Therefore, in this study, we aimed to compare the control of the centre of pressure (COP) in people with Down syndrome (DS) or other causes of ID in relation to people without disabilities and to observe the influence of vision and the practice of dance.
Methods:
This cross-sectional study analyses the COP in a static standing position with open and closed eyes in four study groups. A total of 273 people were recruited (80 adults without ID, 46 adults with DS, 120 adults with other causes of ID and 27 dancers with DS).
Results:
A greater area of oscillation and path of the COP was observed in the participants with ID compared with the participants without ID, especially in the sway area of the COP. The oscillation speed of the COP was also higher. When analysing the displacement of the COP, anteroposterior and mediolateral components, there were also differences, except when comparing the group of dancers with DS with respect to the group without ID. The visual condition only influenced the group of participants without disabilities.
Conclusions:
The results of our study show that there is a less efficient static postural control in people with ID, as greater displacements were observed in the COP of the participants with ID. The differences in some specific variables that analyse the displacement of the COP were smaller when comparing the group of dancers with DS and the individuals without ID.info:eu-repo/semantics/publishedVersio
Hybrid analytical surrogate-based process optimization via Bayesian symbolic regression
Get PDFModular chemical process simulators are widespread in chemical industries to design and optimize production processes with sufficient accuracy. However, convergence issues and entrapment in local optima during process optimization are still challenges to overcome. To circumvent them, surrogate models of first principles simulations have attracted attention as they are easier to handle, with hybrid surrogates combining data-driven surrogate models with mechanistic equations becoming particularly appealing. In this context, this work explores the use of Bayesian symbolic regression to construct and globally optimize hybrid analytical surrogate models of process flowsheets, where some units are approximated with tailored analytical expressions rather than with neural networks or Gaussian processes, which might be harder to globally optimize. Comparing with other prevalent black-box surrogate modeling & optimization approaches, such as kriging and Bayesian optimization, we find that our approach can find better solutions than those identified with pure black-box methodologies, yet model building is much more computationally demanding.info:eu-repo/semantics/publishedVersio
In Vivo Efficacy of an Adhesive Bioresorbable Patch to Treat Aortic Dissections
Get PDFEndovascular repair of aortic dissection still presents significant limitations. Preserving the mechanical and biological properties set by the aortic microstructure is critical to the success of implantable grafts. In this paper, we present the performance of an adhesive bioresorbable patch designed to cover the entry tear of aortic dissections. We demonstrate the power of using a biomimetic scaffold in a vascular environment.info:eu-repo/semantics/publishedVersio
From ethical codes to ethical culture in social and educational action
Get PDFEl presente artículo plantea los elementos para la construcción de una cultura ética en las organizaciones. Inicialmente, se describe el reto de hacer presente la ética en el día a día de la actividad profesional, pero también la dificultad de convertir los ideales en acciones coherentes con los principios y valores institucionales. Se sitúa el contexto profesional en el marco de las teorías de la complejidad y se realiza un análisis sobre la cultura ética desde esta perspectiva. Después de realizar un breve repaso a las principales teorías éticas,
se propone la creación de un sistema o constelación de elementos éticos como definidores de la idea de cultura que supere los planteamientos principialistas. Por último, después de describir los elementos de este sistema, se sugieren unos criterios de aplicación.This article discussed the elements needed to construct an ethical culture within organisations. To this end, firstly, it describes the challenge of making ethics present in day-to-day professional acti-vity, but also the difficulty of converting ideals into actions consistent with institutional principles and values. The professional context is considered within the framework of complexity theory and an analysis is made of ethical culture from this perspective. After a brief review of the main ethical theories, the creation of a system or constellation of ethical elements is proposed to support an idea of culture that goes beyond approaches based on principialism. Finally, after a description of the elements of this system, criteria for its application are suggested.info:eu-repo/semantics/publishedVersio
Jurisdictional approaches to sustainable agro-commodity governance: The state of knowledge and future research directions
Get PDFinfo:eu-repo/semantics/publishedVersio
Assessing the Effects of User Accountability in Contracting Out
Get PDFHow does contracting out affect service performance? Evidence to date is mixed. We argue that this is partially due to prior studies focusing often on whether—not how—services are contracted. Yet, how services are contracted matters. In particular, we argue that whether users pay user fees for services to contractors affects efficiency. Where they do, contractor revenue depends on user satisfaction and contractors face incentives to provide quality services to users to retain revenue. Where, by contrast, governments fund services, information asymmetry about the quality of services users receive allows contractors to shirk quality. The assertion is substantiated by empirical evidence derived from a comprehensive analysis of conditional efficiency within the water supply services across 2,111 municipalities in Spain, employing a two-stage conditional order-m data panel estimation. Our results show that contracting out where users pay service fees and thus have incentives to hold contractors accountable outperforms contracting out without user fees in quality-adjusted service provision.info:eu-repo/semantics/publishedVersio
Relationship between sex, APOE genotype, endocannabinoids and cognitive change in older adults with metabolic syndrome during a 3-year Mediterranean diet intervention
Get PDFBackground
The Mediterranean diet (MedDiet) has demonstrated efficacy in preventing age-related cognitive decline and modulating plasma concentrations of endocannabinoids (eCBs) and N-acylethanolamines (NAEs, or eCB-like compounds), which are lipid mediators involved in multiple neurological disorders and metabolic processes. Hypothesizing that eCBs and NAEs will be biomarkers of a MedDiet intervention and will be related to the cognitive response, we investigated this relationship according to sex and apolipoprotein E (APOE) genotype, which may affect eCBs and cognitive performance.
Methods
This was a prospective cohort study of 102 participants (53.9% women, 18.8% APOE-ɛ4 carriers, aged 65.6 ± 4.5 years) from the PREDIMED-Plus-Cognition substudy, who were recruited at the Hospital del Mar Research Institute (Barcelona). All of them presented metabolic syndrome plus overweight/obesity (inclusion criteria of the PREDIMED-Plus) and normal cognitive performance at baseline (inclusion criteria of this substudy). A comprehensive battery of neuropsychological tests was administered at baseline and after 1 and 3 years. Plasma concentrations of eCBs and NAEs, including 2-arachidonoylglycerol (2-AG), anandamide (AEA), oleoylethanolamide (OEA), palmitoylethanolamide (PEA), and N-docosahexaenoylethanolamine (DHEA), were also monitored. Baseline cognition, cognitive changes, and the association between eCBs/NAEs and cognition were evaluated according to gender (crude models), sex (adjusted models), and APOE genotype.
Results
At baseline, men had better executive function and global cognition than women (the effect size of gender differences was − 0.49, p = 0.015; and − 0.42, p = 0.036); however, these differences became nonsignificant in models of sex differences. After 3 years of MedDiet intervention, participants exhibited modest improvements in memory and global cognition. However, greater memory changes were observed in men than in women (Cohen’s d of 0.40 vs. 0.25; p = 0.017). In men and APOE-ε4 carriers, 2-AG concentrations were inversely associated with baseline cognition and cognitive changes, while in women, cognitive changes were positively linked to changes in DHEA and the DHEA/AEA ratio. In men, changes in the OEA/AEA and OEA/PEA ratios were positively associated with cognitive changes.
Conclusions
The MedDiet improved participants’ cognitive performance but the effect size was small and negatively influenced by female sex. Changes in 2-AG, DHEA, the OEA/AEA, the OEA/PEA and the DHEA/AEA ratios were associated with cognitive changes in a sex- and APOE-dependent fashion. These results support the modulation of the endocannabinoid system as a potential therapeutic approach to prevent cognitive decline in at-risk populations.info:eu-repo/semantics/publishedVersio