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et al., Materials that exhibit ferromagnetism, interfacial stability, and tunability are highly desired for the realization of emerging magnetoelectronic phenomena in heterostructures. Here we present the GdAg monolayer alloy, which possesses all such qualities. By combining X-ray absorption, Kerr effect, and angle-resolved photoemission with ab initio calculations, we have investigated the ferromagnetic nature of this class of Gd-based alloys. The Curie temperature can increase from 19 K in GdAu to a remarkably high 85 K in GdAg. We find that the exchange coupling between Gd atoms is barely affected by their full coordination with noble metal atoms, and instead, magnetic coupling is effectively mediated by noble metal-Gd hybrid s,p-d bands. The direct comparison between isostructural GdAu and GdAg monolayers explains how the higher degree of surface confinement and electron occupation of such hybrid s,p-d bands promote the high Curie temperature in the latter. Finally, the chemical composition and structural robustness of the GdAg alloy has been demonstrated by interfacing them with organic semiconductors or magnetic nanodots. These results encourage systematic investigations of rare-earth/noble metal surface alloys and interfaces, in order to exploit them in magnetoelectronic applications., This work was supported by the Spanish Government (MAT2013-46593-C6-4-P, MAT2013-46593-C6-5-P, FIS2013-48286-C02-02-P, FIS2013-48286-C02-01-P), the Basque Government (IT621-13,IT627-13,IT756-13), the Diputación de Gipuzkoa (RF-0061/2015), and the Deutsche Forschungsgemeinschaft (SFB 1083 “Structure and Dynamics of Internal Interfaces”). A.Mu., M.A.V., and M.G. acknowledge the Severo Ochoa program SEV-2013-0295. B.X. and M.J.V. acknowledge two A.R.C. grants (TheMoTherm 10/15-03 and AIMED 15/19-09) from the Communauté Francaise de ̧ Belgique. Computer time was made available by PRACE-2IP and 3IP (EU FP7 Grant No. RI-283493 and RI-312763), CECI, SEGI-ULg, and the DIPC.

Recent experiments [L. Ju, et al., Nature, 2015, 520, 650] confirm the existence of gapless states at domain walls created in gated bilayer graphene, when the sublattice stacking is changed from AB to BA. These states are significant because they are topologically protected, valley-polarized and give rise to conductance along the domain wall. Current theoretical models predict the appearance of such states only at domain walls, which preserve the sublattice order. Here we show that the appearance of the topologically protected states in stacking domain walls can be much more common in bilayer graphene, since they can also emerge in unexpected geometries, e.g., at grain boundaries with atomic-scale topological defects. We focus on a bilayer system in which one of the layers contains a line of octagon-double pentagon defects that mix graphene sublattices. We demonstrate that gap states are preserved even with pentagonal defects. Remarkably, unlike previous predictions, the number of gap states changes by inverting the gate polarization, yielding an asymmetric conductance along the grain boundary under gate reversal. This effect, linked to defect states, should be detectable in transport measurements and could be exploited in electrical switches., This work was partially supported by the Polish Ministry of Science and Higher Education (The “WZROST” Program) and the Spanish Ministry of Economy and Competitiveness under Grants No. FIS2012-33521, FIS2015-64654-P and FIS2013-48286-C2-1-P.

Liquidambar formosana (also known as maple) is a tall deciduous tree widely distributed in various regions of the South of the Qinling Mountains and Huaihe River in China, and also found in Northern Vietnam, Laos and South Korea. L. formosana is a famous ornamental plant for leaves are green in spring and summer, and red in autumn. Different plant parts of L. formosana, such as leaf, fruit, bark, and resin, are proved to be treasures as natural medicinal plant resources [1]. Among the bioactive constituents, several diterpenoid acids of the abietane family have been identified. Abietic acid (1) occurs in plants of the genus Abies and is the first member of a class of plant metabolites, the abietane-type diterpenoids. They are characterized by a tricyclic ring system and have shown a wide range of chemical diversity and biological activity.[2,3] Medicinal chemists have studied derivatives of two readily available materials such as dehydroabietic acid (2) and dehydroabietylamine (3, DHAA).[3] To date, there is only one commercial drug, Ecabet® [ecabet sodium (4)], based on abietanes, which is used for the treatment of reflux esophagitis and peptic ulcer disease. Ferruginol (5) exhibits anticancer effects in human ovarian cancer and inhibition of cancer cell migration. Recent studies of sugiol (6) demonstrated in vivo antitumor activity in DU145 prostate xenografts. These biological reports and the simultaneous isolation, (in 2014) by Hua and co-workers, of the new abietane liquiditerpenoic acid A (7), a sugiol analogue, from the resin of Liquidambar formosana [4] and from Pinus massoniana,[5] by Kuo and co-workers named independently as abietopinoic acid, prompted us to synthesize it and study its biological properties along with some analogues. References [1] Ouyang, X. L.; Yi, S.; Lu, H. Y.; Wu, S. M.; Zhao, H. Q. Eur. J. Med. Plants 2016, 17, 1-11. [2] For a review on this topic, see: Gonzalez, M. A. Nat. Prod. Rep. 2015, 32, 684-704. [3] For a review on this topic, see: Gonzalez, M. A. Eur. J. Med. Chem. 2014, 87, 834-842. [4] Shang, H.-J.; Li, D.-Y.; Wang, W.-J.; Li, Z.-L.; Hua, H.-M. Nat. Prod. Res. 2014, 28, 1-6. [5] Mohamed, H. A.; Hsieh, C.-L.; Hsu, C.; Kuo, C.-C.; Kuo, Y.-H. Helv. Chim. Acta 2014, 97, 1146-1151.

Shortly after mixing cement grains with water, a cementitious fluid paste is formed that immediately transforms into a solid form by a phenomenon known as setting. Setting actually corresponds to the percolation of emergent network structures consisting of dissolving cement grains glued together by nanoscale hydration products, mainly calcium-silicate-hydrates. As happens in many percolation phenomena problems, the theoretical identification of the percolation threshold (i.e. the cement setting) is still challenging, since the length scale where percolation becomes apparent (typically the length of the cement grains, microns) is many times larger than the nanoscale hydrates forming the growing spanning network. Up to now, the long-lasting gap of knowledge on the establishment of a seamless handshake between both scales has been an unsurmountable obstacle for the development of a predictive theory of setting. Herein we present a true multi-scale model which concurrently provides information at the scale of cement grains (microns) and at the scale of the nano-hydrates that emerge during cement hydration. A key feature of the model is the recognition of cement setting as an off-lattice bond percolation process between cement grains. Inasmuch as this is so, the macroscopic probability of forming bonds between cement grains can be statistically analysed in smaller local observation windows containing fewer cement grains, where the nucleation and growth of the nano-hydrates can be explicitly described using a kinetic Monte Carlo Nucleation and Growth model. The most striking result of the model is the finding that only a few links (~12%) between cement grains are needed to reach setting. This directly unveils the importance of explicitly including nano-texture on the description of setting and explains why so low amount of nano-hydrates is needed for forming a spanning network. From the simulations, it becomes evident that this low amount is least affected by processing variables like the water-to-cement ratio and the presence of large quantities of nonreactive fillers. These counter-intuitive predictions were verified by ex-professo experiments that we have carried out to check the validity of our model., This study was carried out under the umbrella of the BASKRETE initiative and supported by the Basque Government under the ELKARTEK Program (project SUPER). Te computing facilities of TECNALIA, DIPC, and the Supercomputing Center of Galicia CESGA are likewise acknowledged. A.P. acknowledges fnancial support from the TIFER program of TECNALIA and S.A.-I. acknowledges the fnancial support from project IT-654-13 by the Basque government.

The crystal structure of solid-state matter greatly affects its electronic properties. For example in multilayer graphene, precise knowledge of the lateral layer arrangement is crucial, since the most stable configurations, Bernal and rhombohedral stacking, exhibit very different electronic properties. Nevertheless, both stacking orders can coexist within one flake, separated by a strain soliton that can host topologically protected states. Clearly, accessing the transport properties of the two stackings and the soliton is of high interest. However, the stacking orders can transform into one another and therefore, the seemingly trivial question how reliable electrical contact can be made to either stacking order can a priori not be answered easily. Here, we show that manufacturing metal contacts to multilayer graphene can move solitons by several $\mu$m, unidirectionally enlarging Bernal domains due to arising mechanical strain. Furthermore, we also find that during dry transfer of multilayer graphene onto hexagonal Boron Nitride, such a transformation can happen. Using density functional theory modeling, we corroborate that anisotropic deformations of the multilayer graphene lattice decrease the rhombohedral stacking stability. Finally, we have devised systematics to avoid soliton movement, and how to reliably realize contacts to both stacking configurations.

A critical challenge in reducing anthropogenic impacts on the environment is to decrease the carbon footprint of the cement industry. A key concern in the search for more sustainable cement designs is the understanding and control of the depolymerization process that eventually determines the integrity of their silicate chains under mechanical, chemical, or thermal stresses. Herein, we use metadynamics to show that the depolymerization of cement silicate skeletons consists of hydroxylation followed by bond-breaking. We then clarify the local effects of doping the silicate chains: a stable pentacoordinate state following hydroxylation is promoted by aluminum atoms but restrained by phosphorus additions, the presence of two dopants being related to energy landscapes less favorable to bond-breaking. The role of these dopants is explained in cement-based materials and is key to the quest for low-cost opportunities to preserve the strength of cement for high temperatures or even over time., This work was supported by the Spanish Government (FIS2016-76617-P), the Basque Government through the ELKARTEK project (SUPER), and the University of the Basque Country (Grant No. IT-756-13).

Educating our early career researchers is becoming far more difficult. The model of supervision should be flexible and adjusted along the way. There is not a universal model that is beneficial for all the student-supervisor relationships. It is important to find which model is more suitable depending on the stage of the PhD (1-4 year) but also the characteristics of both PhD student and supervisor. Becoming an effective supervisor requires training. Higher research institutions should implement strategies and plans of action to enhance the supervision skills of their staff. This work analyses the PhD student perspective about which model of supervision is considered as the most suitable in Spain.

Silicate-chains polymerization is a crucial process in calcium silicate hydrate minerals, with large relevance for improving the durability and reducing the environmental impact of cement-based materials. To better understand the evolutionary mechanisms underlying the polymerization of silicate-chains in layered calcium silicate hydrates, we herein propose to trace the evolution of the polymerization degree by using silicon isotopes. The method requires tabulating the isotopic fractionation of several basic chemico–physical mechanisms that we obtained by performing atomistic simulations. The calculations reveal that the highly polymerized structures have longer Si–O bonds and that the Ca2+ cations play a dual role in the stretching and bending mode properties of silicates, such as isotopic fractionation is able to discern not only between the polymerization order of calcium silicate hydrate minerals, but even between cement gels suffering calcium leaching. Silicon isotopic fractionation can, therefore, be used to quantify the different evolutions of calcium silicon hydrate phases in a sample of man-made gel cement in order to improve its sustainability along lifetime stages in the quest for green cement., This work was supported by the Spanish Government (FIS2016-76617-P), the Basque Government through the ELKARTEK project (SUPER), and the University of the Basque Country (Grant No. IT-756-13).

Mn and Fe-doped GaN are widely studied prototype systems for hole-mediated magnetic semiconductors. The nature of the hole states around the Mn and Fe impurities, however, remains under debate. Our self-interaction corrected density-functional calculations show that the charge neutral Mn0 and positively charged Fe+ impurities have symmetry-broken d5+h ground states, in which the hole is trapped by one of the surrounding N atoms in a small polaron state. We further show that both systems also have a variety of other d5+h configurations, including symmetric, delocalized states, which may be stabilized by axial strain. This finding opens a pathway to promote long-range hole-mediated magnetic interactions by strain engineering and clarifies why highly strained thin-films samples often exhibit anomalous magnetic properties., This work was funded by JSPS Grant-in-Aid for Scientific Research (C) No. 17K05494. H.R. is grateful to the São Paulo Research Foundation FAPESP and S.B. thanks the Rotary Yoneyama Memorial Foundation for support. A.A. acknowledges support of the Project FIS2016-76617-P of the Spanish Ministry of Economy and Competitiveness MINECO.

Experiments in gated bilayer graphene with stacking domain walls present topological gapless states protected by no-valley mixing. Here we research these states under gate voltages using atomistic models, which allow us to elucidate their origin. We find that the gate potential controls the layer localization of the two states, which switches non-trivially between layers depending on the applied gate voltage magnitude. We also show how these bilayer gapless states arise from bands of single-layer graphene by analyzing the formation of carbon bonds between layers. Based on this analysis we provide a model Hamiltonian with analytical solutions, which explains the layer localization as a function of the ratio between the applied potential and interlayer hopping. Our results open a route for the manipulation of gapless states in electronic devices, analogous to the proposed writing and reading memories in topological insulators., This work was partially supported by Projects FIS2015-64654-P and FIS2016-76617-P of the Spanish Ministry of Economy and Competitiveness MINECO, the Basque Government under the ELKARTEK project (SUPER), and the University of the Basque Country (Grant No. IT-756-13).

Oligonucleotides used for the molecular identification and characterization of Giardia duodenalis in this study. (DOCX 13 kb)

Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://link.springer.com/article/10.1007%2Fs11030-018-9830-7 This is the peer reviewed version of the following article: Sánchez Salgado, JC., Bilbao Ramos, P., Dea Ayuela, MA., Hernández Luis, F., Bolás Fernández, F., Medina Franco, JL. & Rojas Aguirre, Y. (2018). Systematic search for benzimidazole compounds and derivatives with antileishmanial effects. Molecular Diversity, vol. 22, n. 4 (nov.), pp. 779-790, which has been published in final form at https://doi.org/10.1007/s11030-018-9830-7. Este es el post-print del siguiente artículo: Sánchez Salgado, JC., Bilbao Ramos, P., Dea Ayuela, MA., Hernández Luis, F., Bolás Fernández, F., Medina Franco, JL. & Rojas Aguirre, Y. (2018). Systematic search for benzimidazole compounds and derivatives with antileishmanial effects. Molecular Diversity, vol. 22, n. 4 (nov.), pp. 779-790, que se ha publicado de forma definitiva en https://doi.org/10.1007/s11030-018-9830-7. Leishmaniasis is a neglected tropical disease that currently affects 12 million people, and over 1 billion people are at risk of infection. Current chemotherapeutic approaches used to treat this disease are unsatisfactory, and the limitations of these drugs highlight the necessity to develop treatments with improved efficacy and safety. To inform the rational design and development of more efficient therapies, the present study reports a chemoinformatic approach using the ChEMBL database to retrieve benzimidazole as a target scaffold. Our analysis revealed that a limited number of studies had investigated the antileishmanial effects of benzimidazoles. Among this limited number, L. major was the species most commonly used to evaluate the antileishmanial effects of these compounds, whereas L. amazonensis and L. braziliensis were used least often in the reported studies. The antileishmanial activities of benzimidazole derivatives were notably variable, a fact that may depend on the substitution pattern of the scaffold. In addition, we investigated the effects of a benzimidazole derivative on promastigotes and amastigotes of L. infantum and L. amazonensis using a novel fluorometric method. Significant antileishmanial effects were observed on both species, with L. amazonensis being the most sensitive. To the best of our knowledge, this chemoinformatic analysis represents the first attempt to determine the relevance of benzimidazole scaffolds for antileishmanial drug discovery using the ChEMBL database. The present findings will provide relevant information for future structure–activity relationship studies and for the investigation of benzimidazole-derived drugs as potential treatments for leishmaniasis.

BACKGROUND: Giardia duodenalis is one of the most common enteric parasites in domestic animals including dogs. Young animals are more prone to the infection, with clinical manifestations ranging from asymptomatic to acute or chronic diarrhoea. Dogs are primarily infected by canine-specific (C-D) assemblages of G. duodenalis. However, zoonotic assemblages A and B have been increasingly documented in canine isolates, raising the question of whether and to which extent dogs can act as natural reservoirs of human giardiosis. METHODS: In this cross-sectional epidemiological survey we assessed the molecular diversity of G. duodenalis in dogs in the province of Castellón, Eastern Spain. A total of 348 individual faecal samples from sheltered (n = 218), breeding (n = 24), hunting (n = 68), shepherd (n = 24), and pet (n = 14) dogs were collected between 2014 and 2016. Detection of G. duodenalis cysts in faecal material was carried out by direct fluorescence microscopy as a screening test, whereas a qPCR targeting the small subunit ribosomal RNA gene of the parasite was subsequently used as a confirmatory method. RESULTS: Giardia duodenalis was detected in 36.5% (95% CI: 31.6-41.7%) of dogs. No significant differences in prevalence rates could be demonstrated among dogs according to their sex and geographical origin, but breeding (45.8%; 95% CI: 27.9-64.9%) and sheltered (40.4%; 95% CI: 34.1-47.0%) dogs harboured significantly higher proportions of G. duodenalis. Multi-locus sequence-based genotyping of the glutamate dehydrogenase and β-giardin genes of G. duodenalis allowed the characterization of 35 canine isolates that were unambiguously assigned to assemblages A (14.3%), B (22.9%), C (5.7%), and D (37.1%). A number of inter-assemblage mixed infections including A + B (11.4%), A + D (2.9%), and A + B + D (5.7%) were also identified. CONCLUSIONS: Data presented here are strongly indicative of high infection pressures in kennelled animals. Zoonotic sub-assemblages AII, BIII, and BIV were responsible for a considerable proportion of the G. duodenalis infections detected, but very few of the genotypes identified have been previously documented in Spanish human populations. Although possible, zoonotic transmission between dogs and humans seems an infrequent event in this Spanish region. This study was funded by the Health Institute Carlos III, Ministry of Economy and Competitiveness under project CP12/03081. Additional funding was obtained from the CEU-Santander/Zoocan Study. Sí

Thermoelectric measurements for graphene ribbons are currently performed on samples that include atomic disorder via defects and irregular edges. In this work, we investigate the thermopower or Seebeck coefficient of graphene ribbons within the linear response theory and the Landauer formalism, and we consider the diffusive regime taken as a limit of the ribbon aspect ratio. We find that the thermopower and the electronic conductivity depend not only on the aspect ratio, but also on chemical potential and temperature, which are set here as key parameters. The obtained numerical results with temperature and doping are brought into contact with the thermoelectric measurements on disordered graphene ribbons with good agreement., Comment: 5 pages and 3 figures

Histogram of cycle threshold (Ct) values obtained by real-time PCR for the detection of Giardia duodenalis in DNA isolates from canine faecal samples. (DOCX 31 kb)

Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://pubs.acs.org/doi/10.1021/acs.molpharmaceut.8b00097 This is the pre-peer reviewed version of the following article: Smith, L., Serrano, DR., Mauger, M., Bolás-Fernández, F., Dea-Ayuela, MA. & Lalatsa, A. (2018). Orally bioavailable and effective Buparvaquone lipid-based nanomedicines for visceral leishmaniasis. Molecular Pharmaceutics, vol. 15, n. 7 (15 may), pp. 2570-2583, which has been published in final form at https://doi.org/10.1021/acs.molpharmaceut.8b00097. Este es el pre-print del siguiente artículo: Smith, L., Serrano, DR., Mauger, M., Bolás-Fernández, F., Dea-Ayuela, MA. & Lalatsa, A. (2018). Orally bioavailable and effective Buparvaquone lipid-based nanomedicines for visceral leishmaniasis. Molecular Pharmaceutics, vol. 15, n. 7 (15 may), pp. 2570-2583, que se ha publicado de forma definitiva en https://doi.org/10.1021/acs.molpharmaceut.8b00097. Nano-enabled lipid based drug delivery systems offer a platform to overcome challenges encountered with current failed leads in the treatment of parasitic and infectious diseases. When prepared with FDA or EMA approved excipients, they can be readily translated without the need for further toxicological studies, while they remain affordable and amenable to scale-up. Buparvaquone (BPQ), a hydroxynapthoquinone with in vitro activity in the nanomolar range, failed to clinically translate as a viable treatment for visceral leishmaniasis due to its poor oral bioavailability limited by its poor aqueous solubility (BCS Class II drug). Here we describe a self-nanoemulsifying system (SNEDDS) with high loading and thermal stability up to 6 months in tropical conditions able to enhance the solubilisation capacity of BPQ in gastrointestinal media as demonstrated by flow-through cell and dynamic in vitro lipolysis studies. BPQ SNEDDS demonstrated an enhanced oral bioavailbility compared to aqueous BPQ dispersions (probe – sonicated) resulting in an increased plasma AUC0-24 by 55% that is four fold higher than any previous reported values for BPQ formulations. BPQ SNEDDS can be adsorbed on low molecular glycol chitosan polymers forming solid dispersions that when compressed into tablets allow the complete dissolution of BPQ in gastrointestinal media. BPQ SNEDDS and BPQ solid SNEDDS demonstrated potent in vitro efficacy in the nanomolar range (

Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: http://www.eurekaselect.com/167132/article Este es el post-print del siguiente artículo: Dea Ayuela, MA. and Serrano López, DR. (2018). New drugs and therapeutic-diagnostic targets for fungal and parasitic diseases. Part II. Current Topics in Medicinal Chemistry, vol. 18, n. 16, p. 1357, que se ha publicado de forma definitiva en https://doi.org/10.2174/156802661816181107142130 This is the peer reviewed version of the following article: Dea Ayuela, MA. and Serrano López, DR. (2018). New drugs and therapeutic-diagnostic targets for fungal and parasitic diseases. Part II. Current Topics in Medicinal Chemistry, vol. 18, n. 16, p. 1357, which has been published in final form at https://doi.org/10.2174/156802661816181107142130.