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La ciencia de las consecuencias
No full textLas acciones tienen consecuencias, y la capacidad de aprender de ellas revolucionó la vida en la Tierra. Aunque es bastante evidente que las consecuencias son importantes (¿dónde estaríamos sin el reforzamiento positivo?), pocos saben que existe una ciencia de las consecuencias con principios que nos afectan cada día. A pesar de su variedad, las consecuencias parecen seguir un conjunto común de principios científicos y comparten algunos efectos comunes en el cerebro, por ejemplo, en los llamados "centros de placer". El sistema genética-ambiente siempre opera de forma integrada, y los científicos han demostrado que aprender de las consecuencias activa de manera predecible los genes y reestructura nuestro cerebro. Las aplicaciones posibles de esta ciencia de las consecuencias están en todas partes, en el hogar, en el trabajo y en el ámbito escolar, por mencionar algunos ejemplos. A nivel individual y social, por ejemplo, el autocontrol se enfrenta a menudo a las consecuencias a corto y largo plazo. Después de diez años de trabajo, La Ciencia de las Consecuencias narra una historia que abarca desde la genética hasta los neurotransmisores, desde la emoción hasta el lenguaje, desde la educación infantil hasta la política, adoptando un enfoque interdisciplinario inclusivo para mostrar cómo algo tan aparentemente simple puede ayudar a dar sentido a tantas cosas. Este título ha recibido numerosos elogios de expertos reconocidos en genética, neurociencia y economía, así como en psicología, análisis de conducta y entrenamiento animal en medios como Nature, The Scientist y Science News
Examinando la relación entre los canales de distribución en línea y la satisfacción y lealtad de los turistas
No full textAlthough the Internet and e-commerce have contributed positively to
the tourism sector, there is not much empirical research on the
transformation of distribution channels or that considers the use of the
Internet in travel planning as an antecedent of tourist satisfaction and
loyalty. This paper aims to test the influence of online distribution
channels in trip planning by tourists on their general satisfaction level
and their loyalty towards the destination and to differentiate the profile
of digital and traditional tourists. Quantitative research techniques are
used to analyse the dataset of 1,387 surveys of tourists visiting the
province of Burgos, Spain. Among those surveyed, 65% search for
information online and 54% book or pay for services online. According
to ordinal regression analysis, the use of online channels does not
significantly influence the level of satisfaction, but according to binary
logistic regression, it does significantly influence loyalty. The findings
provide valuable information for developing marketing strategies in
tourism organisations and support decision-makers in creating
competitive tourism destinations that are resilient to the demographic
challenge of depopulation.A pesar de que Internet y el comercio electrónico han contribuido
positivamente al sector turístico, no existen muchas investigaciones
empíricas sobre la transformación de los canales de distribución ni que
consideren el uso de Internet en la planificación del viaje como un
antecedente de la satisfacción y lealtad del turista. Este trabajo pretende
comprobar la influencia de los canales de distribución online en la
planificación del viaje de los turistas sobre su nivel de satisfacción global
y su lealtad al destino y diferenciar el perfil de los turistas digitales y
tradicionales. Se utilizan técnicas de investigación cuantitativa para
analizar el conjunto de datos formado por 1.387 encuestas de turistas que
visitan la provincia de Burgos, España. Entre los encuestados, el 65% busca
información online y el 54% reserva o paga servicios online. Según el
análisis de regresión ordinal, el uso de los canales en línea no influye
significativamente en el nivel de satisfacción, pero según la regresión
logística binaria, influye significativamente en la lealtad. Los resultados
proporcionan información valiosa para el desarrollo de estrategias de
marketing en las organizaciones turísticas y apoyan a los responsables de
la toma de decisiones en la creación de destinos turísticos competitivos
resilientes ante el reto demográfico de la despoblación.This work was financially supported by the Society for the Development of the Province of Burgos, thanks to the collaboration agreement signed between the University of Burgos and this institution for the development of actions included in the Rural Strategic Plan of Burgos (PEBUR 15-20) in the fields of tourism, environmental economics and human capital and by the State Research Agency (Ministry of Science and Innovation of the Government of Spain) and FEDER Funds (Knowledge Generation Projects) through the project "Methodologies for solving problems with economic, social and environmental criteria. Application to healthcare resource management" (ECOSOEN-HEALTH, grant ref. PID2022- 139543OB-C44). The authors deeply appreciate the financial support received
A review on the thermal conductivity of deep eutectic solvents
No full textDeep eutectic solvents may develop a pivotal role in future technologies considering sustainability and safety as pivotal aspects for chemistry developments. The possible application of these fluids for heat transfer operations is of great relevance for which the knowledge of thermal properties such as thermal conductivity is required as well as inferring structure–property relationships which allow reverse design of the fluids according to the technological requirements. Considering the technological relevance of this property, the available literature on the thermal conductivity for deep eutectic solvents is critically discussed showing strengths and weaknesses. The analysis of the state-of-the-art shows the future needs in this research field considering the application of these solvents for thermal-related technologies. The review indicates the scarcity of reliable experimental data and the need of predictive methods, which could be used for process design and solvent screening purposes. Likewise, considering the relevance of developing predictive methods for in silico design of these fluids according to industrial needs, the available predictive theoretical approaches are analysed showing their reliability as well as future needs. Finally, considering the need of developing suitable and reliable structure–property relationship, the molecular level basis of thermal conductivity in deep eutectic solvents is discussed, showing the role of hydrogen bonding and the effects rising from the involved hydrogen bond donors and acceptors as well as the eutectic compositions. This work reports the first literature review and analysis on thermal conductivity for deep eutectic solvents considering an experimental and theoretical approach as well as providing support for the molecular basis of this technologically relevant property, thus contributing to the development of environmentally friendly materials for thermal-related technologies.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature
Silver hexacyanoferrate (II) nanocrystals as a new material to improve Raman scattering enhancement during silver surface oxidation
Get PDFRaman spectroscopy is a powerful analysis technique that shows its full potential when a high amplification of the Raman signal is achieved. In this sense, Surface-Enhanced Raman scattering (SERS) has been the most widely used phenomenon for analysis. SERS provides the amplification of the Raman intensity due to the interaction of molecules with a plasmonic nanostructured surface. The enhancement of the Raman signal can be also obtained during the electrochemical oxidation of a metal electrode; this phenomenon was denoted as Electrochemical-Surface Oxidation Enhanced Raman Scattering (EC-SOERS) and yields a good Raman signal enhancement with high reproducibility. Until now, only chloride and bromide have been employed in EC-SOERS, using a silver electrode to generate silver chloride and silver bromide nanocrystals. In this work, a new EC-SOERS substrate based on the electrogeneration of silver hexacyanoferrate (II) nanocrystals is presented which provides a very sensitive Raman response. The electrogeneration of this new material can be easily followed using spectroelectrochemistry since the characteristic Raman bands of the nanocrystals lie outside of the fingerprint region used for the analysis where the detection of most of the target molecules is performed. Indigo Carmine has been selected as target molecule, obtaining a very good response at nanomolar level under Raman resonance and non-resonance conditions.Authors acknowledge the financial support from Ministerio de Ciencia e Innovación and Agencia Estatal de Investigación (MCIN/AEI/10.13039/501100011033, PID2020–113154RB-C21), and Ministerio de Ciencia, Innovación y Universidades (RED2022–134120-T). S.H. thanks JCyL and European Social Fund for her postdoctoral fellowship and M.P.-E. thanks JCyL and European Social Fund for his predoctoral fellowship. W. Ch. acknowledges Junta de Castilla y León for his postdoctoral fellowship (Grant BU297P18) and funding received from European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 101031622
Boron nitride-reinforced porous aramid composites with enhanced mechanical performance and thermal conductivity
Get PDFAramids are materials with high-performance properties and used in advanced applications, including bulletproof vests and aerospace industry components. Consequently, research is focused on improving their properties and reducing their density to achieve fuel reduction and enhanced comfort. Herein we describe the preparation of dense, micro, and nanoporous aramid films containing hexagonal boron nitride (hBN) with two objectives: improving mechanical performance and increasing thermal conductivity (TC) in porous films for specific applications. The preparation procedure is simple and scalable, involving the addition of hBN and a porosity promoter to control the porous structure in the film's casting solution. Tensile tests revealed that the inclusion of 10% of hBN in microporous aramids led to a 130% increase in Young's modulus and 63% reduction in material's density compared to the dense commercial aramid. The orientation of the hBN in the films was also evaluated by considering the XRD and the thermal properties of the films. The films containing hBN exhibited enhanced TC and thermal diffusivity (TD) together with a very low density and improved mechanical performance, which can benefit applications in the aerospace industry, protective equipment, and battery separators.This work was supported by the Regional Government of Castilla y León (Junta de Castilla y León), the Ministry of Science and Innovation MICIN and the European Union NextGenerationEU/PRTR, and the Spanish Agencia Estatal de Investigación (State Research Agency) (PID2019-108583RJ-I00/AEI/10.13039/501100011033)
Brønsted Acid-Catalyzed Synthesis of 4-Functionalized Tetrahydrocarbazol-1-ones from 1,4-Dicarbonylindole Derivatives
Get PDFA p-toluenesulfonic acid-catalyzed cascade reaction is reported for the synthesis of 4-functionalized tetrahydrocarbazolones via the reaction of 4-(indol-2-yl)-4-oxobutanal derivatives with a variety of nucleophiles in acetonitrile or hexafluoroisopropanol. After the initial intramolecular Friedel–Crafts hydroxyalkylation, the 3-indolylmethanol intermediate is subsequently activated and reacted with the external nucleophile. The reaction conditions are crucial to avoid alternative reaction pathways, allowing direct substitution reaction with thiols, (hetero)arenes, alkenes, or sulfinates. The procedure features high overall yields to access a diverse family of compounds bearing the tetrahydrocarbazole core.We gratefully acknowledge Ministerio de Ciencia e Innovación (PID2020-115789GB-C21/AEI/10.13039/501100011033), and Junta de Castilla y León and FEDER (BU049P20) for financial support. S.G.-G. thanks Ministerio de Educación for a FPU predoctoral contract. S.S.-P. thanks a Ramón y Cajal (RYC2021-031533-I) contract funded by MCIN/AEI/10.13039/501100011033 and European Union “NextGenerationEU”/PRTR
Synthesis of 1,4-ketoaldehydes and 1,4-diketones by Mo-catalyzed oxidative cleavage of cyclobutane-1,2-diols
Get PDFA new two-step procedure for the synthesis of 1,4-dicarbonyls has
been developed involving an efficient and clean Mo-catalyzed oxidative cleavage of cyclobutane-1,2-diols with DMSO, which is used
as solvent and oxidant. The required starting glycols were prepared
by nucleophilic additions of organolithiums and Grignard reagents
to easily available 2-hydroxycyclobutanones.We gratefully acknowledge Ministerio de Ciencia e Innovación and FEDER (PID2020-115789GB-C21), and Junta de Castilla y León and FEDER (BU049P20) for financial support. S. G.-G. and R. H.-R. thank Ministerio de Educación for FPU predoctoral contracts. S. S.-P. thanks Ministerio de Ciencia e Innovación and “NextGenerationEU”/PRTR EU for a Ramón y Cajal contract (RYC2021-031533-I)
Arqueología molecular: "letras biológicas" para una época sin escritura
No full textA partir del descubrimiento de la genética y las moléculas implicadas en los
caracteres hereditarios se abrieron nuevos campos para el estudio y la utilización de este
conocimiento. La arqueología incluyó estas moléculas para el estudio de la prehistoria en
los años 90 del pasado siglo. La tecnología y empleo de moléculas, ADN principalmente, y
proteínas en los últimos diez años para el estudio de la prehistoria ha crecido de forma
exponencial llegando a publicarse una media de 3.000 publicaciones anuales en lo que
llevamos de década. Con el presente trabajo se pretende poner en valor su utilización y el
conocimiento que ha generado la arqueología molecular.From the discovery of genetics and the molecules involved in hereditary traits, new
windows were opened for the study and use of this knowledge. Archeology included these
molecules for the study of prehistory in the 90s of the twentieth century. The technology
and use of molecules, DNA, and proteins in the last decade for the study of prehistory has
grown exponentially, reaching an average of 3,000 publications per year so far this decade.
The present work intends to value its use and the knowledge that molecular archeology has
generated
Neural network modelling and prediction of an Anaerobic Filter Membrane Bioreactor
No full textAnaerobic membrane bioreactors have become an environmentally friendly solution for wastewater treatment.
The lack of sufficiently accurate mathematical procedures to model their behaviour and the fouling process of
the membranes, poses a challenge when trying to optimise their energy consumption and maintenance costs.
An accurate model of the fouling process of the membranes is critical to make the most of this technology. This
is a perfect scenario in which to introduce neural networks (NN) as an alternative to mathematical modelling.
However, the duration of the experiments and the difficulties in measuring some relevant variables, make it
hard to collect high quality datasets to train the NN. Our goal is to obtain a good prediction of the fouling
status of the membranes to enable an adjustment of operation conditions and maintenance procedures ahead
in time. To do so we must obtain high quality datasets to train our neural networks. The combination of static
and dynamic networks enables us to leverage the best prediction capabilities of each one. This combination
requires a preprocessing of the datasets that separates trends from oscillations. The outputs obtained need to
be put together to build up the predicted evolution of fouling. Accurate predictions are then extended from
25 to up to 75 filtration cycles. To maintain and even extend accuracy after sudden changes in operating
conditions, retraining the NN every 25 cycles is proposed. AI based real time predictions open a new scope
for decision making, and optimisation in the field of anaerobic membrane reactors.This work is part of the project TED2021-132393B-I00, funded by the MCIN/AEI/10.13039/501100011033 and the European Union ‘‘NextGenerationEU’’/PRTR
Dataset of the work “Raman spectroelectrochemical determination of clopyralid in tap water”
No full textClopyralid is a common herbicide used all around the world that can be dissolved in the rain stream and accumulate in underground water with the potential threat of reaching drinking water. Many methodologies have been proposed to perform quantitative analysis of this compound but, to this day, no Raman detection of clopyralid has been carried out. Here, a novel methodology to quantify clopyralid, based on Electrochemical Surface Oxidation-Enhanced Raman Scattering (EC-SOERS), is developed, using disposable silver screen-printed electrodes as substrate. The optimization of the electrolytic media is carried out, searching for the conditions where a maximum Raman enhancement is obtained. Moreover, a study about the effect of various interfering compounds, which could be present in water, on the clopyralid Raman response is performed. The results demonstrate that the presented methodology allows the determination of clopyralid in the micromolar range in tap water without any purification or preconcentration step, requiring few minutes to perform the measurement of each sample.Authors acknowledge Ministerio de Ciencia e Innovacion and Agencia Estatal de Investigacion (MCIN/AEI/10.13039/501100011033, PID2020-113154RB-C21), Junta de Castilla y Leon (Grant BU297P18) and Ministerio de Ciencia, Innovacion y Universidades (RED2018–102412-T) for the support of this work. Martín Perez and Sheila Hernandez acknowledge Junta de Castilla y Leon for their predoctoral contracts