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In recent years, social networks have become an important communication platform through which candidates promote the political engagement of their constituents.One of the variables that could influence this ability to generate engagement through social networks is the use of messages with a significant emotional charge, both positive and negative. Our research aims to delve into the analysis of this relationshipbetween political engagement and emotions in social networks, through the Sentiment Analysis in the tweets of the main candidates in the general elections of April and November 2019 in Spain. For this we resort to the technique of text extraction and its analysis with the Linguistic Inquiry and Word Count (LIWC) software, relating the level of presence of positive and negative emotions, with the level of engagement reached by the candidates during the electoral campaign. Our analysis helps to demonstrate the existence of a relationship between the emotional charge of the discourse on social networks and the level of engagement it generates, although this seems to be also mediated by the political agenda and the campaign strategy of the parties. We also verify that the relationship between emotional discourse and engagement towards a leader is not exclusively endogenous, but may also be due to exogenous elements due to the presence of shared digital communities. Las redes sociales se han convertido en los últimos años en una importante plataforma de comunicación a través de la que los candidatos promueven el compromiso político de sus electores. Una de las variables que podría influir en esa capacidad de generar engagementa través de las redes sociales es la utilización de mensajes con una importante carga emocional, tanto positiva como negativa. Nuestra investigación tiene como objetivo profundizar en el análisis de dicha relación entre el compromiso político y las emociones en las redes sociales, mediante el Análisis de Sentimientos en los tuits de los principales candidatos en las elecciones generales de abril y noviembre de 2019 en España. Para ello recurrimos a la técnica de extracción de textos y su análisis con el software Linguistic Inquiry and Word Count (LIWC), poniendo en relación el nivel de presencia de emociones positivas y negativas, con el nivel de compromiso alcanzado por los candidatos durante la campaña electoral. Nuestro análisis contribuye a demostrar la existencia de relación entre la carga emocional del discurso en las redes sociales y el nivel de engagement que genera, aunque este parece estar mediatizado además por la agenda política y la estrategia de campaña de los partidos. Comprobamos además que la relación entre discurso emocional y engagement hacia un líder no es exclusivamente endógena, sino que puede obedecer también a elementos exógenos debido a la presencia de comunidades digitales compartidas.

espanolIntroduccion: El objetivo que persigue este trabajo es analizar si los diversos usos que los ciudadanos realizan de las redes sociales tienen relacion con el voto a los partidos politicos y con las emociones que los ciudadanos sienten hacia los lideres politicos. De ser asi, podriamos asumir que la plataformizacion es un proceso politizado y emocionado y que esa politizacion y emocionalidad del proceso vincula el tipo de uso que los ciudadanos hacen de las redes. Metodologia: Este trabajo se ha planteado como un estudio de caso mediante un enfoque metodologico cuantitativo que plantea tanto un analisis descriptivo e interdependencia de los datos. Resultados: el analisis del consumo de redes en funcion del voto muestra la existencia de un patron diferenciado en funcion de este ultimo. Una tendencia que se replica en lo relativo al uso especifico de las redes concretas. Discusion: los datos respecto a la expresion emocional de enfado y miedo concuerdan con las posturas defendidas en la literatura. Conclusiones: estos hallazgos se suman a los ya existentes respecto a la importancia de las redes como “camaras de eco” que amplifican los debates que en ellas se producen, en una suerte de “espiral emocional”. EnglishIntroduction: The objective pursued by this research is to determine if there is a diversified use of social networks in our country and what is the relationship that such use has with the vote for political parties that citizens express, as well as with the presence emotional towards political leaders. If so, we could assume that the plataformizacion is a politicized and excited process and that this politicization and emotionality of the process links the type of use those citizens make of the networks. Methodology: This work has been proposed as a case study using a quantitative methodological approach that proposes both a descriptive and interdependency analysis of the data. Results: the analysis of the consumption of networks according to the vote shows the existence of a differentiated pattern according to the latter. A trend that is replicated in relation to the specific use of specific networks. Discussion: the data regarding emotional expression of anger and fear agree with the positions defended in the literature. Conclusions: these findings are in addition to those already existing regarding the importance of networks as "echo chambers" that amplify the debates that occur in them, in a kind of "emotional spiral".

We report the structure and charge transport properties of a novel solid-state proton conductor obtained by acid-base chemistry via proton transfer from 12-tungstophosphoric acid to imidazole. The resulting material (henceforth named Imid3WP) is a solid salt hydrate that, at room temperature, includes four water molecules per structural unit. To our knowledge, this is the first attempt to tune the properties of a heteropolyacid-based solid-state proton conductor by means of a mixture of water and imidazole, interpolating between water-based and ionic liquid-based proton conductors of high thermal and electrochemical stability. The proton conductivity of Imid3WP·4H2O measured at truly anhydrous conditions reads 0.8 × 10-6 S cm-1 at 322 K, which is higher than the conductivity reported for any other related salt hydrate, despite the lower hydration. In the pseudoanhydrous state, that is, for Imid3WP·2H2O, the proton conductivity is still remarkable and, judging from the low activation energy (Ea = 0.26 eV), attributed to structural diffusion of protons. From complementary X-ray diffraction data, vibrational spectroscopy, and solid-state NMR experiments, the local structure of this salt hydrate was resolved, with imidazolium cations preferably orienting flat on the surface of the tungstophosphate anions, thus achieving a densely packed solid material, and water molecules of hydration that establish extremely strong hydrogen bonds. Computational results confirm these structural details and also evidence that the path of lowest energy for the proton transfer involves primarily imidazole and water molecules, while the proximate Keggin anion contributes with reducing the energy barrier for this particular pathway.

[Abstract] We study the microscopic structure and transport properties of ions in mixtures of 1-butyl-3-methylimidazolium and 1-butyl-3-ethylimidazolium iodide with ethanol using atomistic molecular dynamics simulations and conductivity measurements. Compared with the same ionic liquids in water, we reveal essential differences in ionic structure that are closely related to the differences in the solubility mechanisms of both types of solvents. In particular, unlike for aqueous solutions, we find a homogeneous distribution of solvent molecules in the system, i.e., we observe no cluster formation, which agrees with the nano-structured solvation paradigm. In addition, we calculate the conductivities of these systems in the whole concentration range and compare them with experimental data. Although the simulated values slightly underestimate the experimental ones, they reproduce the shape of the experimental conductivity dome reasonably well. We also show that the pseudo-lattice random-alloy model, which is based on microscopic ion jumping frequencies, describes the conductivity data accurately. We compute the average jumping frequencies directly from simulations and find that they agree well with those obtained by fitting the simulation conductivity data. These results show that the pseudo-lattice random-alloy model provides a valuable tool to describe the conductivities of ionic liquid–solvent mixtures and particularly their concentration dependence. It shall also apply to other systems, e.g., inorganic electrolytes and dispersed ionic conductors. The financial support of the Spanish Ministry of Economy and Competitiveness (Projects MAT2017-89239-C2-1-P and MAT2017-89239- C2-2-P) is gratefully acknowledged. Moreover, this work was funded by the Xunta de Galicia (ED431D 2017/06, ED431E 2018/08, GRC ED431C 2016/001 and GRC ED431C 2020/10). All these research projects were partially supported by FEDER. The help of the technician M. C. V. from UDC for some of the measurements presented is also acknowledged. H. M-C. and J. M. O-M. thank the Spanish Ministry of Education for their FPU grant, and H. M-C. thanks the USC for his “Convocatoria de Recualificación do Sistema Universitario Español-Margarita Salas” postdoc grant under the “Plan de Recuperación Transformación” program funded by the Spanish Ministry of Universities with European Union’s NextGenerationEU funds Xunta de Galicia; ED431D 2017/06 Xunta de Galicia; ED431E 2018/08 Xunta de Galicia; ED431C 2016/001 Xunta de Galicia; ED431C 2020/10

Asystematic review of the Mediterranean region species of the sylvicola group of Corticaria Marsham, 1802 is carried out. An identification key for the determination of those 21 species is provided. Morphological structures of the studied species are re-appraised and figures are provided of head, antennae, pronotum, and aedeagus with internal armature. The true identity of Corticaria tunisiensis Brisout de Barneville, 1884 is established by examination of the specimens of the collection of National Museum of Natural History, Paris, here designating a male lectotype and paralectotypes of both sexes.

Over the last few years, European public broadcasters have promoted the concept of public service media as one of their main values. To this end, transparency policies have been implemented as a mechanism of corporate projection by strengthening their role as an essential service. The objective of this article is to ascertain the existence of this type of policies among European public broadcasters. To this end, a nominal group was made with 24 experts who were surveyed, thus generating new indicators of transparency and accountability strategies around sustainability and digitalization. The contents of the websites of RTVE (Spain), RTP (Portugal), France TV (France), RAI (Italy), BBC (UK), RTÉ (Ireland), ZDF (Germany), VRT (Belgium), and SVT (Sweden) were also analyzed, paying attention to such indicators and strategies. The main results include the identification of differences on the basis of the ideal models described by Hallin and Mancini, a commitment to credibility (fact-checking) to the detriment of diversity of opinions, and a connection between the political system and the media system, which, preliminarily, determines the level of transparency of these public entities.

Graphical abstract, Highlights • A novel thermophilic esterase discovered from hot-spring metagenomic library. • EstD11 shows broad substrate specificity including substrates of industrial interest. • Atomic resolution crystallographic complexes reveal hot-spots in the active site. • High-T structures provide unique evidence on cap dynamics as occurs in vivo. • Met zipper at active site essential in thermo-stability and substrate promiscuity., A novel esterase, EstD11, has been discovered in a hot spring metagenomic library. It is a thermophilic and thermostable esterase with an optimum temperature of 60°C. A detailed substrate preference analysis of EstD11 was done using a library of chromogenic ester substrate that revealed the broad substrate specificity of EstD11 with significant measurable activity against 16 substrates with varied chain length, steric hindrance, aromaticity and flexibility of the linker between the carboxyl and the alcohol moiety of the ester. The tridimensional structures of EstD11 and the inactive mutant have been determined at atomic resolutions. Structural and bioinformatic analysis, confirm that EstD11 belongs to the family IV, the hormone-sensitive lipase (HSL) family, from the α/β-hydrolase superfamily. The canonical α/β-hydrolase domain is completed by a cap domain, composed by two subdomains that can unmask of the active site to allow the substrate to enter. Eight crystallographic complexes were solved with different substrates and reaction products that allowed identification of the hot-spots in the active site underlying the specificity of the protein. Crystallization and/or incubation of EstD11 at high temperature provided unique information on cap dynamics and a first glimpse of enzymatic activity in vivo. Very interestingly, we have discovered a unique Met zipper lining the active site and the cap domains that could be essential in pivotal aspects as thermo-stability and substrate promiscuity in EstD11.

Capture of pharmaceutical pollutants from water was studied using a novel fluorine-bearing covalent organic framework TpBD-(CF3)(2), which showed ibuprofen adsorption capacity of 119 mg g(-1) at neutral pH. This value is further enhanced at pH 2, highlighting the potential of this class of materials to serve as adsorbents even under harsh conditions. The adsorbed pharmaceutical can be recovered from TpBD-(CF3)(2) in high yield, offering the option of recycling both the adsorbent and the pharmaceutical. The high efficiency of ibuprofen capture as compared to other less lipophilic pharmaceuticals suggests that COFs can be pre-designed for selective capture of contaminants.

Micrambe micoae sp. n. (Coleoptera: Cryptophagidae) from the Iberian Peninsula, the Cabañeros National Park, Ciudad Real, Spain, is described. Differential diagnosis with M. ulicis (Stephens, 1830) is established.

The stability of binary mixtures of several protic ionic liquids (ethylammonium nitrate, ethylammonium acetate and ethylammonium tetrafluoroborate) with polyethylene oxide is studied by means of molecular dynamics simulations. The solubility range is seen to be wider for ethylammonium acetate, and the structure and single-particle dynamics of its ternary mixtures with lithium acetate are then studied. The structure of liquid mixtures of lithium acetate with the ionic liquid is seen to be seldom modified by the addition of the polymer, with very limited hydrogen bonding between the ionic liquid and the polymer taking place. Moreover, lithium is seen to be solvated in the liquid phase forming [Li(ACE)4]−3 tetrahedral complexes irrespective of the presence of the polymer, with very limited binding of metal cations to oxygen atoms in the polymer backbone. Hence, the registered single particle dynamics and lithium transport takes place in practically the same way as in the liquid phase with almost no interference of the polymer, contrarily to previously reported results for other ionic liquids.

Anew species, Monotoma (Monotomina) bousqueti, is described. It was found in La Manga, Province of Murcia, Spain.We present its differences with the nearest known species, M. (M.) quadrifoveolata Aubé, 1837.

We perform molecular dynamics simulations of ionic liquids confined between graphene walls under a large variety of conditions (pure ionic liquids, mixtures with water and alcohols, mixtures with lithium salts and defective graphene walls). Our results show that the formation of striped and hexagonal patterns in the Stern layer can be considered as a general feature of ionic liquids at electrochemical interfaces, the transition between patterns being controlled by the net balance of charge in the innermost layer of adsorbed molecules. This explains previously reported experimental and computational results and, for the first time, why these pattern changes are triggered by any perturbation of the charge density at the innermost layer of the electric double layer (voltage and composition changes, and vacancies at the electrode walls, among others), which may help tuning electrode-ionic liquid interfaces. Using Monte Carlo simulations we show that such structures can be reproduced by a simple two-dimensional lattice model with only nearest-neighbour interactions, governed by highly screened ionic interactions and short-range and excluded volume interactions. We also show that the results of our simulations are consistent with those inferred from the Landau-Brazovskii theory of pattern formation in self-assembling systems. The presence of these patterns at the ionic liquid graphene-electrode interfaces may have a strong impact on the process of ionic transfer from the bulk mixtures to the electrodes, on the differential capacitance of the electrode-electrolyte double layer or on the rates of redox reactions at the electrodes, among other physicochemical properties, and is therefore an effect of great technological interest., 8 pages, 5 figures, Physical Chemistry Chemical Physics

Targeted irreversible inhibitors bearing electrophiles that become activated towards covalent bond formation upon binding to a specific protein/enzyme is an emerging area in drug discovery. Targeting lysine residues is challenging due to the intrinsically low reactivity of the amino group at physiological pH. Herein we report the first example of a hydroxylammonium derivative that causes a specific covalent modification of an active-site and a sterically inaccessible lysine residue of an enzyme. The described ligands, compounds 1–3, were rationally designed to be activated towards covalent bond formation upon binding to the type I dehydroquinase (DHQ1) enzyme for the development of new anti-virulence agents to combat the widespread resistance to antibiotics. Evidence in atomic detail for the covalent modifications caused by the ligands to the catalytic Lys170 by the formation of a stable secondary amine is provided by the resolution at 1.08–1.25 Å of the crystal structures of DHQ1 from Salmonella typhi enzyme adducts. In addition, the first crystal structure of the addition intermediate adduct at 1.4 Å of a Schiff base formation reaction by using an analog of the natural substrate, compound 4, is also reported. Molecular dynamics simulation studies on non-covalent enzyme/ligand complexes and a two-dimensional QM/MM umbrella sampling simulation study suggested that a direct displacement by Lys170 with the release of NH2OH would be feasible. These studies might open up new opportunities for the development of novel lysine-targeted irreversible inhibitors bearing a methylhydroxylammonium moiety as a latent electrophile., Financial support from the Spanish Ministry of Economy and Competiveness (SAF2016-75638-R), the Xunta de Galicia [Centro singular de investigación de Galicia accreditation 2016-2019 (ED431G/09) and ED431B 2018/04] and the European Union (European Regional Development Fund – ERDF) is gratefully acknowledged.

A density functional theory study of the effect of the adsorption of a mixture of potassium salt and an imidazolium-based ionic liquid on the electronic and optical properties of graphene and borophene is performed. This addition leads to a downward shift of the Dirac cone for both structures due to the electron transferred from potassium to the graphene and borophene sheets. The transferred charge to the wall and the binding energy of potassium are bigger than in the case of the adsorption of potassium on pristine graphene. The Bader analysis shows that the presence of potassium makes the charge distributions in graphene and the layers of boron atoms in borophene more homogenous and the electronic distribution in the sheets is consequently less affected by the electromagnetic interaction with the ions in the mixture. Moreover, the results show that the optical properties are altered by the metallic cation, especially at low frequencies where ionic liquid-enhanced 2D plasmons are registered due to the doping of 2D sheets by electrons transferred from the potassium atoms leading to near zero values of the parallel components of the dielectric function and refractive index.

In this work we study how the properties of ionic liquids change upon confinement between two walls at various nanometric distances. We also find a correlation between the dynamic properties and the structure of this system under these extremely nanoconfined circumstances. We report that for ethylammonium nitrate, the ionic structure inside the simulation boxes is a consequence of a subtle combination of ion packing, hydrogen bonding, electrostatic and van der Waals forces. We also study how the dynamical properties of this material change in these conditions, showing a decrease in the ionic mobility for very low slit sizes, recovering the bulk behavior as the distance between walls increases. Moreover, when short wall separations are considered, we show that the ionic mobility at short times is a minimum when the hydrogen bonding is also a minimum. Finally, we show that the effect of the interface in the long time ion dynamics only extends to a quite small region (ca. 1.35 nm) next to the walls. We show that the overall behavior of the nanoconfined liquid in the slit pore can be described by the superposition of a bulk and a confined simulation with a fitted wall separation. To our knowledge, there are no similar studies characterizing this kind of dense ionic systems in such a fine-grain way under these ultra-nanoconfined conditions.

In this paper, we present a molecular dynamics study of ammonia solutions in a protic ionic liquid with a structurally similar cation, ethylammonium nitrate. Using two different models of the ammonia molecule, a conventional 4-site model and a 6-site model optimizing the dipolar and quadrupolar electron distributions, we evaluate their effect on the microstructure and single-particle dynamics of these mixtures, as well as on their behaviour at the electrochemical interface. Quite significant differences are found on the solvation of ammonia in these dense ionic solvents, the 6-atom model predicting a stronger affinity of solvent molecules for the cations of the solvent as well as a caging effect on NH3 solvation shells, not predicted by the 4-site model. Finally, we discuss the structure of the liquid layers near charged graphene walls. The structure in the layer next to the wall varies with the charge on the wall and varies with the model used for ammonia.

12 pags., 17 figs., 1 tab., Molecular dynamics simulations are reported for a protic (ethylammonium nitrate) and an aprotic (1-ethyl-3-methylimidazolium tetrafluoroborate) ionic liquid nanoconfined inside a faujasite-templated carbon. The structure and dynamics of ionic species inside nanotubes of relevant sizes are studied in order to understand the behavior of the dense ionic solvents in the zeolite-templated carbon. The structure (density, coordination numbers) of the confined fluid reflects a mixed dimensionality inside the zeolite-templated carbon, while the single-particle dynamics shows fundamental changes relative to that of ionic liquids confined in carbon nanotubes. Finally, no significant differences are found between the protic and the aprotic ionic liquids, which seems to suggest that the influence of hydrogen bonding is heavily suppressed inside the zeolite-templated carbon., The financial support of the Spanish Ministry of Economy and Competitiveness (Projects MAT2017-89239-C2-1-P and MAT2017-89239-C2-2-P) is gratefully acknowledged. Moreover, this work was fundedby the Xunta de Galicia (ED431D 2017/06, ED431E 2018/08 and GRCED431C 2016/001). All these research projects were partially supportedby FEDER. H.M.-C. and J.M.O.-M. thank the Spanish Ministry of Education for their FPU grant. T. M.-M. thanks the Spanish Ministry of Science,Innovation and Universities for her Juan de la Cierva grant (IJC2018-036774-I). E.L acknowledges the support from the Agencia Estatal deInvestigación and Fondo Europeo de Desarrollo Regional (FEDER) undergrant No. FIS2017-89361-C3-2-P. Facilities provided by the Galician Supercomputing Centre (CESGA) are also acknowledged.

We present a comparative density functional theory study of the electronic and optical properties of graphene and borophene with an adsorbed ionic liquid. The Dirac cones of these two-dimensional nanostructures are not affected by the presence of the ionic liquid close to these sheets, not even in the borophene one in which a very small charge transfer to the ionic liquid anion is detected. However, Bader analysis and charge density calculations showed that the polarization of the ionic liquid induces a redistribution of the electric charge in both sheets as a consequence of the electromagnetic interaction between the anion and cation of the ionic liquid and the electrons on the two-dimensional materials, the effect being notably stronger in graphene than in borophene. Our calculations reveal that several changes take place in the dielectric constant and electron energy loss spectra, including shifts and damping of plasmon bands, related to electrostatically induced changes in the adsorbent surface electron charge distributions and to plasmon loss channels associated to excitations of electrons in the energy levels of the adsorbed ionic liquid species close to the Fermi level of the surface material. While only minor changes are registered in borophene plasmon spectra and in the IR and visible regions of the graphene spectra, important changes in the graphene ultraviolet C and X-ray spectra are registered due to the existence of IL electronic energy levels close to the Fermi level of graphene that are absent in borophene.

The synthesis of highly functionalized bicyclic and cyclic β-amino acids from β-nitrosugars is reported. Specifically, our strategy for the synthesis of polyhydroxylated cyclopentane β-amino acids via the intramolecular C-alkylation of 6-nitro-2-O-triflates of furanosides has been applied to the preparation of the first two examples of a novel class of bicyclic β-amino acids and a novel cyclopentene β-amino acid. Also, our Henry reaction mediated strategy for the synthesis of polyhydroxylated cyclohexane β-amino acids has been extended to a divergent, stereoselective synthesis of new polysubstituted cyclohexane and cyclopentane β-amino acids.

Mixtures of the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate with amphiphilic cosolvents, such as methanol and ethanol, nanoconfined between graphene walls are studied by means of molecular dynamics simulations and the results are compared with those of the pure ionic liquid and its mixtures with water confined in the same conditions. We investigate the adsorption of cosolvent molecules at the graphene walls as well as their distribution across the system. The results show that, due to a higher affinity of the polar groups to be close to the anions in combination with the electrostatic and excluded volume interactions, there exists a high tendency of the OH groups to lie close to the anode, inducing small changes in the first cation layer. The orientation of cosolvent molecules is found to be closely related to the alignment of the molecular dipole moment. We also investigate the lateral ionic distribution in the layers close to the electrodes, which shows a structural transition from liquid-like lamellar ordering to solid-like hexagonal patterns as the size of the cosolvent molecules increases leading to smaller position fluctuations of the ions. The dependence of the specific patterns on the nature of the electrodes is also studied. This study strongly suggests that the ionic patterns formed in the first ionic layers next to the charged interfaces are universal since their existence does not crucially depend on the atomic composition of the interfacial material, but only on the net charge density of the considered ionic layer, which significantly changes the ionic mobility in this region.

The first example of an ammonium derivative that causes a specific modification of the active site of type I dehydroquinase (DHQ1), a dehydratase enzyme that is a promising target for antivirulence drug discovery, is described. The resolution at 1.35 Å of the crystal structure of DHQ1 from Salmonella typhi chemically modified by this ammonium derivative revealed that the ligand is covalently attached to the essential Lys170 through the formation of an amine. The detection by mass spectroscopy of the reaction intermediates, in conjunction with the results of molecular dynamics simulations, allowed us to explain the inhibition mechanism and the experimentally observed differences between S. typhi and Staphylococcus aureus enzymes. The results presented here reveal that the replacement of Phe225 in St-DHQ1 by Tyr214 in Sa-DHQ1 and its hydrogen bonding interaction with the conserved water molecule observed in several crystal structures protects the amino adduct against further dehydration/aromatization reactions. In contrast, for the St-DHQ1 enzyme, the carboxylate group of Asp114, with the assistance of this water molecule, would trigger the formation of a Schiff base that can undergo further dehydration reactions until full aromatization of the cyclohexane ring is achieved. Moreover, in vitro antivirulence studies showed that the reported compound is able to reduce the ability of Salmonella Enteritidis to kill A459 respiratory cells. These studies have identified a good scaffold for the design of irreversible inhibitors that can be used as drugs and has opened up new opportunities for the development of novel antivirulence agents by targeting the DHQ1 enzyme Financial support from the Spanish Ministry of Science and Innovation (SAF2013-42899-R), Xunta de Galicia (GRC2013-041), and the European Regional Development Fund (ERDF) is gratefully acknowledged. E.L. thanks the Xunta de Galicia for his postdoctoral fellowship. A.B. thanks the Miguel Servet Programme ISCIII-FEDER (CP13/00226) and the ISCIIIGeneral Subdirection of Assesment and Promotion of the Research (PI14/00059) for financial support SI

The integration of units of differing natures which are found in different parts of some multilevel personality models is one of the most thought-provoking paths in contemporary research. In the field of compulsive buying, little is known about the interrelationships between the comparative and stable units such as personality traits (basic tendencies or Level I units) and goals (a kind of middle-level unit) which are more related to motivational processes and intentions governing peoplersquo;s behavior.Self-reporting measures of compulsive buying, Big Five personality traits, and extrinsic life aspirations were administered to a general population sample consisting of 2,159 participants aged 15 to 65 (48.1% males; Mage= 35.4, SD= 13.24).Our results confirmed statistically significant associations with compulsive buying for the traits as well as the extrinsic goals. Furthermore, an important relationship between both levels in personalityndash; traits vs . extrinsic life aspirationsndash; was found. Finally, extrinsic life aspirations (specially, image, popularity, and conformity) contribute to the potentiation of the prediction of compulsive buying beyond the Five Factor Model.Current findings emphasize the advisability of considering both levels in personality, traits and middle-level units like life aspirations, not only in the prediction of compulsive buying, but also as potential targets for preventive and treatment programs.

The structural and dynamical properties of bulk mixtures of long-chained primary and secondary alcohols (propanol, butanol, and 2-pentanol) with protic ionic liquids (ethylammonium and butylammonium nitrate) were studied by means of molecular dynamics simulations and small angle X-ray scattering (SAXS). Changes in the structure with the alcohol concentration and with the alkyl chain length of the alcohol moieties were found, showing variations in the radial distribution function and in the number of hydrogen bonds in the bulk liquids. Moreover, the structural behaviour of the studied mixtures is further clarified with the spatial distribution functions. The global picture in the local scale is in good agreement with the nanostructured solvation paradigm [T. Mendez-Morales et al. Phys. Chem. B 118, 761 (2014)], according to which alcohols are accommodated into the hydrogen bonds’ network of the ionic liquid instead of forming clusters in the bulk. Indeed, our study reveals that the alcohol molecules are placed with their polar heads at the interfaces between polar and nonpolar nanodomains in the ionic liquid, with their alkyl chains inside the nonpolar organic nanodomains. The influence of alcohol chain length in the single-particle dynamics of the mixtures is also reported calculating the velocity autocorrelation function and vibrational densities of states of the different species in the ionic liquid-alcohol mixtures, and a weak caging effect for the ethylammonium cations independent of the chain size of the alcohols was found. However, the SAXS data collected for the studied mixtures show an excess of the scattering intensities which indicates that there are also some structural heterogeneities at the nanoscale.

Solvation in mixtures of 1-ethyl-3-methylimidazolium acetate ionic liquid with water in a molar concentration of 5% is studied by means of atomistic molecular dynamics (MD) simulations. We employed a spherical coarse-grained parameterization to describe a model solute and we performed MD simulations with positively charged, negatively charged and neutral model spheres and compare the results with those previously reported in pure ionic liquids. Our study reveals that water does not significantly perturb the structure of the electric double layer neither the orientation of ions in the neighborhood of the solute particle. Although water does not seem to play any significant role in the solvation of neutral solutes, there is an excess of water in the first and second ionic solvation shell of both charged solutes, respectively. We also studied the correlation between the electric field around the negatively charged model solute and the orientation of the dipole moment of water molecules, finding that, although the dynamic properties of water molecules are almost unaltered in the presence of the solutes, and the ionic cage around the central solutes is only slightly affected upon water addition, the mobility of the spheres is drastically enhanced.

In order to investigate the effect of defects on the structure of an electrode on the electric double layer of ionic-liquid-based electrolytes, we perform classical molecular dynamic simulations on mixtures of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) and lithium tetrafluoroborate (LiBF4) near charged graphene electrodes with different percentages of single defect vacancies, assuming planarity of the defected graphene, as follows from our density-functional theory calculations. Defects on the electrode's surface modify the surface charge density at the innermost layer of the electrochemical interface, which allows studying the structure of the electric double layer at a constant density of ions without changing either the voltage or the electrolyte composition. Indeed, we report that the presence of defects on the graphene electrodes can induce structural transitions in the innermost layer of the electric double layer. This result is supported by a thorough analysis of the structural properties of the layer and its energy landscape, particularly showing that there is a direct correlation between this defect-induced layer structure and the adsorption of the salt cations at the electrode, which is of utmost importance for the usage of these novel electrolytic mixtures in actual electrochemical devices.

Intrigued by the not fully extended hairpin monomeric structure of the previously reported cyclo-(αβ3αβ 2α)2 peptide 2, as well as its nanochannel crystallographic assembly, we here investigate the structural properties of a series of turn derivatives (3-17). Five crystallographic monomeric structures of the symmetric and asymmetric cyclo- (αβ3αβ2α)2 peptides 3-17 are found; the novel saddlelike (4 and 16) and the twisted hairpin (6) conformers, as well as the not fully extended hairpins 7 and 14. The pentafluorophenyl/1-naphthyl and pentafluorophenyl/9-phenanthryl derivatives 7 and 14, respectively, adopt the anticipated hexagon-shaped crystalline nanotube assemblies, resembling the crystal packing of the parent peptide 2. The structural analysis of the compounds as described here can serve as a basis for biological applications, such as the design of β-sheet mimics or for the development of functional nanomaterials. © 2013 American Chemical Society.

In the search for alternative non‐metabolizable inducers in the l ‐rhamnose promoter system, the synthesis of fifteen 6‐deoxyhexoses from l ‐rhamnose demonstrates the value of synergy between biotechnology and chemistry. The readily available 2,3‐acetonide of rhamnonolactone allows inversion of configuration at C4 and/or C5 of rhamnose to give 6‐deoxy‐d ‐allose, 6‐deoxy‐d ‐gulose and 6‐deoxy‐l ‐talose. Highly crystalline 3,5‐benzylidene rhamnonolactone gives easy access to l ‐quinovose (6‐deoxy‐l ‐glucose), l ‐olivose and rhamnose analogue with C2 azido, amino and acetamido substituents. Electrophilic fluorination of rhamnal gives a mixture of 2‐deoxy‐2‐fluoro‐l ‐rhamnose and 2‐deoxy‐2‐fluoro‐l ‐quinovose. Biotechnology provides access to 6‐deoxy‐l ‐altrose and 1‐deoxy‐l ‐fructose.

The first stereocontrolled synthesis of (3R,4R,5R,6S)-2,2-bis-(hydroxymethyl)azepane-3,4,5,6-tetraol is described herein. The method involves a novel double Henry reaction of the 3,5-di-O-benzyl-6-deoxy-1,2-O-isopropylidene-6-nitro-α-d-glucofuranose with formaldehyde followed by a reductive ring closure to give the first branched 1,6-dideoxy-1,6-heptitol described. © 2008 Elsevier Ltd. All rights reserved.

This work describes the behaviour of water molecules in 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid under nanoconfinement between graphene sheets. By means of molecular dynamics simulations, an adsorption of water molecules at the graphene surface is studied. A depletion of water molecules in the vicinity of the neutral and negatively charged graphene surfaces and their adsorption at the positively charged surface are observed in line with the preferential hydration of the ionic liquid anions. The findings are appropriately described using a two-level statistical model. The confinement effect on the structure and dynamics of the mixtures is thoroughly analyzed using the density and the potential of mean force profiles, as well as by the vibrational densities of states of water molecules near the graphene surface. The orientation of water molecules and the water-induced structural transitions in the layer closest to the graphene surface are also discussed., Comment: 14 pages, 7 figures, to appear in Journal of Physics: Condensed Matter

A series of gramicidin S derivatives 4-15 are presented that have four ornithine residues as polar protonated side chains and two central hydrophobic amino acids with unaltered turn regions. These peptides were screened against human erthrocytes and our standard panel of Gram negative- and Gram positive bacteria, including four MRSA strains. Based on the antibacterial- and hemolytic data, peptides 13 and 14 have an improved biological profile compared to the clinically applied topical antibiotic gramicidin S. © 2012 Elsevier Ltd. All rights reserved.

Enoyl-acyl carrier protein reductase (ENR; the product of the fabI gene) is an important enzyme that is involved in the type II fatty-acid-synthesis pathway of bacteria, plants, apicomplexan protozoa and mitochondria. Harmful pathogens such as Mycobacterium tuberculosis and Plasmodium falciparum use the type II fatty-acid-synthesis system, but not mammals or fungi, which contain a type I fatty-acid-synthesis pathway consisting of one or two multifunctional enzymes. For this reason, specific inhibitors of ENR are attractive antibiotic candidates. Triclosan, a broad-range antibacterial agent, binds to ENR, inhibiting fatty-acid synthesis. As humans do not have an ENR enzyme, they are not affected. Here, high-resolution structures of Thermus thermophilus (Tth) ENR in the apo form, bound to NAD(+) and bound to NAD(+) plus triclosan are reported. Differences from and similarities to other known ENR structures are reported; in general, the structures are very similar. The cofactor-binding site is also very similar to those of other ENRs and, as reported for other species, triclosan leads to greater ordering of the loop that covers the cofactor-binding site, which, together with the presence of triclosan itself, presumably provides tight binding of the dinucleotide, preventing cycling of the cofactor. Differences between the structures of Tth ENR and other ENRs are the presence of an additional β-sheet at the N-terminus and a larger number of salt bridges and side-chain hydrogen bonds. These features may be related to the high thermal stability of Tth ENR.

The first stereocontrolled nitro sugar-mediated synthesis of polyhydroxylated β-amino acids and their incorporation into peptides is described. The key steps of this approach are a Michael addition of the lithium salt of tris(phenylthio)methane (a carboxyl synthetic equivalent) to sugar nitro olefins, and the reduction of the nitro group to an amino group. Specifically, two glyceraldehyde-based β-amino acids and a polyhydroxylated cyclohexyl β-amino acid were prepared. The latter, which could act as a water-soluble mimic of the proline-glycine δ-turn, was easily transformed into the corresponding 5-amino-6-(hydroxymethyl)cyclohexane-1,2,3,4-tetraol, a novel amino-carbasugar. However, this did not show significant glycosidase inhibiting properties. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A strategy for the synthesis of the novel (6b R ,7 R ,8 S ,9 S ,10 S ,10a R )-8-(benzyloxy)-7,9,10-trihydroxy-6b,7,8,9,10,10a-hexahydro-11 H -benzo[ a ]carbazole-5,6-dione is reported. The key steps were the Michael addition of 2-hydroxy-1,4-naphthoquinone to 1-nitrocyclohexene or 3- O -benzyl-5,6-dideoxy-1,2- O -isopropylidene-6-nitro-α- d - xylo -hex-5-enefuranose and the diastereoselective intramolecular Henry reaction of 3- O -benzyl-5,6-dideoxy-5-C-(3′-hydroxy-1′,4′-naphthoquinon-2′-yl)-1,2- O -isopropylidene-6-nitro-α- d -glucofuranose to give the key (1 S ,2 S ,3 S ,4 R ,5 R ,6 R )-3-(benzyloxy)-1,2,4-trihydroxy-5-(3′-hydroxy-1′,4′-naphthoquinon-2′-yl)-6-nitrocyclohexane. When 2-hydroxy-1,4-naphthoquinone was replaced by (1,4-dimethoxynaphthalen-2-yl)lithium, the novel (1 R ,2 S ,3 S ,4 R ,4a S ,11b S )-2-(benzyloxy)-1,3,4-trihydroxy-1,2,3,4,4a,5-hexahydro-11b H -benzo[ b ]carbazole-6,11-dione was obtained.

β-Secretase is one of the aspartic proteases involved in the formation of amyloid plaques in Alzheimer's disease patients. Our previous results using a combination of surface plasmon resonance experiments with molecular modeling calculations suggested that the Asp dyad in β-secretase bound to hydroxylethylene containing inhibitors adopts a neutral charged state. In this work, we show that the Asp dyad diprotonated state reproduced the binding ranking of a set of these inhibitors better than alternative protonation states.

Monobenzylated sugar amino acids (SAAs) that differ in ether ring size (containing an oxetane, furanoid, and pyranoid ring) were synthesized and incorporated in one of the β-turn regions of the cyclo-decapeptide gramicidin S (GS). CD, NMR spectroscopy, modeling, and X-ray diffraction reveal that the ring size of the incorporated SAA moieties determines the spatial positioning of their cis-oriented carboxyl and aminomethyl substituents, thereby subtly influencing the amide linkages with the adjacent amino acids in the sequence. Unlike GS itself, the conformational behavior of the SAA-containing peptides is solvent dependent. The derivative containing the pyranoid SAA is slightly less hydrophobic and displays a diminished haemolytic activity, but has similar antimicrobial properties as GS.

The main objective of this study is analyze the inter-relationships between the main stressors posing difficulties for school coexistence (students’ disruptive behavior, the teachers’ perception of a lack of social support and conflict), different personal variables (Type A behavior pattern, optimism, hardiness) and burnout. Furthermore, personal variables will be tested to see whether they mediate the influence of the different sources of stress analyzed in burnout. From the results obtained, using a sample of 1537 secondary education teachers, the covariation between the different sets of variables analyzed is not only confirmed but also significant support is given for the mediation hypothesis (stressors would have an indirect influence on burnout through personal variables). Another interesting finding is the need to include in the resulting model a direct effect between the students’ disruptive behavior and the teacher’s burnout experience. In short, the resulting path confirms the personal variables analyzed as a necessary filter in the analysis of the stressors-burnout link, while at the same time integrating the direct effect that students’ disruptive behavior has on teacher’s occupational malaise. .

A divergent synthesis of the two novel polyhydroxylated azepanes (2R,3R,4R,5R,6R)-2-(hydroxymethyl)azepane-3,4,5,6-tetraol and (2R,3R,4R,5R,6S)-2-(hydroxymethyl)azepane-3,4,5,6-tetraol from d -mannose is described. The method involves a Henry reaction between dimethyl-tert-butylsilyl 2,3-O-isopropylidene-α- d -lyxo-pentodialdo-1,4-furanoside and 2-nitroethanol followed by a reductive ring closure of the resulting epimeric nitro aldols. Glycosidase inhibition tests showed that (2R,3R,4R,5R,6S)-2-(hydroxymethyl)azepane-3,4,5,6-tetraol exhibits a weak but selective inhibition against α- l -fucosides.

The synthesis of new analogues of the cationic antimicrobial peptide gramicidin S, having a modified D-phenylalanine residue, their antibacterial properties against several Gram positive and negative strains, as well as their hemolytic activity is reported. (C) 2009 Elsevier Ltd. All rights reserved.

The natural product Gramicidin S is a promising scaffold for novel oligopeptide-based bisphosphine ligands, combining the advantageous rigid chiral backbone with the close proximity of phosphine substituents. The required unnatural, phosphine-containing, amino acid building blocks were synthesized by means of a novel protocol that involves the enantioselective alkylation of a chiral nickel Schiff base template. Three Ni complexes were prepared with different alkyl chains between the phosphine group and the α-carbon atom of the incorporated glycine; the absolute stereochemistry of two of them was determined by single-crystal X-ray structure analysis. By detaching the template, enantiopure L-phosphine amino acids resulted enabling the solid-phase, stepwise construction of a linear sequence of the phosphine-modified oligopeptides. On cyclization three bisphosphine-substituted Gramicidin S analogues resulted, differing only in the size and shape of the linkage between the phosphine groups and the oligopeptides backbone. Their crystal structures suggest these species to have potential as chelating ligands. © 2009 Wiley-VCH Verlag GmbH & Co.

This study examines not only the role of students‟ disruptive be haviour and/or attitudes but also the difficulties perceived by teachers in managing conflicts as a function of the different sociodemographic and occupational variables (gender, age, professional experience, teaching cycle). The results obtained from a sample consisting in 1386 ESO teachers allow us to conclude that both types of stressors validly discriminate as a function of sociodemographic and occupational variables. Specifically, the stress associated to students‟ disruptive behaviour and to the difficulties faced by teachers in managing conflict has a greater incidence on female teachers, on second cycle teachers and on intermediate stages in the profession. If these findings are corroborated by further research, it would be important to design prevention and/or intervention programmes that are sensitive to these risk factors.

En este trabajo se examina, en función de distintas variables sociodemográficas y ocupacionales (sexo, edad, experiencia profesional, ciclo de docencia), no sólo el papel de las conductas y/o actitudes problemáticas de los alumnos, sino también las dificultades percibidas por los profesores en el manejo de conflictos. Los resultados obtenidos, a partir de una muestra de 1.386 docentes de ESO, permiten concluir que ambos tipos de estresores diferencian válidamente en función de las variables sociodemográficas y ocupacionales. Concretamente, el estrés asociado a los problemas de comportamiento de los alumnos y a las dificultades del docente en el manejo de conflictos, incide en mayor medida en las profesoras, en los docentes de segundo ciclo y en aquellas etapas intermedias de la profesión. En definitiva, si estos hallazgos se ratifican en futuras investigaciones, se trataría de diseñar programas preventivos y/o de intervención que sean sensibles a estos factores de riesgo.Palabras clave: Estrés, profesores, conductas problema alumnos, manejo conflictos. This study examines not only the role of students’ disruptive behaviour and/or attitudes but also the difficulties perceived by teachers in managing conflicts as a function of the different sociodemographic and occupational variables (gender, age, professional experience, teaching cycle). The results obtained from a sample consisting in 1386 ESO teachers allow us to conclude that both types of stressors validly discriminate as a function of sociodemographic and occupational variables. Specifically, the stress associated to students’ disruptive behaviour and to the difficulties faced by teachers in managing conflict has a greater incidence on female teachers, on second cycle teachers and on intermediate stages in the profession. If these findings are corroborated by further research, it would be important to design prevention and/or intervention programmes that are sensitive to these risk factors.Key words: Stress, teachers, students’ disruptive behaviour, conflict management.

We describe herein preliminary results on the novel Michael addition of naphthoquinones to nitroolefins and its application to the first synthesis of the novel (6b R,10a S)-7,8,9,10,10a,11-hexahydro-6b H-benzo[ A]carbazole-5,6-diones and (4a R,11b S)-1,2,3,4,4a,5-hexahydro-11b H-benzo[ B]carbazole-6,11-diones, together with a novel synthesis of 1,2,3,4-tetrahydro-5 H-benzo[ B]carbazole-6,11-diones.

A novel promising strategy for the transformation of nitrosugars into branched pyrrolidines, based on double Henry reaction with formaldehyde followed by reductive ring closure, allowed the first enantiospecific synthesis of a 4-C-hydroxymethyl branched derivative of the well-known glycosidase inhibitor 1,4-dideoxy-1,4-imino-pentanol. This strategy also afforded a new route to some other interesting derivatives, such as N-hydroxy, N-propyloxy, and imino derivatives, a new kind of compounds with promising biological properties. [reaction: see text].

The irreversible inhibition of type I dehydroquinase (DHQ1), the third enzyme of the shikimic acid pathway, is investigated by structural, biochemical and computational studies. Two epoxides, which are mimetics of the natural substrate, were designed as irreversible inhibitors of the DHQ1 enzyme and to study the binding requirements of the linkage to the enzyme. The epoxide with the S configuration caused the covalent modification of the protein whereas no reaction was obtained with its epimer. The first crystal structure of DHQ1 from Salmonella typhi covalently modified by the S epoxide, which is reported at 1.4 Å, revealed that the modified ligand is surprisingly covalently attached to the essential Lys170 by the formation of a stable Schiff base. The experimental and molecular dynamics simulation studies reported here highlight the huge importance of the conformation of the C3 carbon of the ligand for covalent linkage to this type of aldolase I enzyme, revealed the key role played by the essential His143 as a Lewis acid in this process and show the need for a neatly closed active site for catalysis Financial support from the Spanish Ministry of Science and Innovation (SAF2013-42899-R), Xunta de Galicia (GRC2013-041) and the European Regional Development Fund (ERDF) is gratefully acknowledged. LT, AP and MM thank the Spanish Ministry of Education for their respective FPU fellowships. EL and JMO thank and the Xunta de Galicia for their respective postdoctoral fellowships SI

A stereoselective synthesis of two complex 1,2-dialkyl-2-amino-1-ethanols [(5S,6S)-6-amino-2,8-dimethylnonan-5-ol and (5S,6S)-6-amino-7-cyclohexyl-2- methylheptan-5-ol] is described from 5-azido-3,5,6-trideoxy-6-isopropyl-L-idose and 5-azido-3,5,6-trideoxy-6-cyclohexyl-Lidose respectively. ©ARKAT USA, Inc.