In silico molecular studies of antiophidic properties of the amazonian tree Cordia nodosa Lam

We carried out surveys on the use of Cordia nodosa Lam. in the jungles of Bobonaza (Ecuador). We documented this knowledge to prevent its loss under the Framework of the Convention on Biological Diversity and the Nagoya Protocol. We conducted bibliographic research and identified quercetrin as a significant bioactive molecule. We studied its in silico biological activity. The selected methodology was virtual docking experiments with the proteins responsible for the venomous action of snakes. The molecular structures of quercetrin and 21 selected toxins underwent corresponding tests with SwissDock and Chimera software. The results point to support its antiophidic use. They show reasonable geometries and a binding free energy of −7 to −10.03 kcal/mol. The most favorable values were obtained for the venom of the Asian snake Naja atra (5Z2G, −10.03 kcal/mol). Good results were also obtained from the venom of the Latin American Bothrops pirajai (3CYL, −9.71 kcal/mol) and that of Ecuadorian Bothrops asper snakes (5TFV, −9.47 kcal/mol) and Bothrops atrox (5TS5, −9.49 kcal/mol). In the 5Z2G and 5TS5 L-amino acid oxidases, quercetrin binds in a pocket adjacent to the FAD cofactor, while in the myotoxic homologues of PLA2, 3CYL and 5TFV, it joins in the hydrophobic channel formed when oligomerizing, in the first one similar to α-tocopherol. This study presents a case demonstration of the potential of bioinformatic tools in the validation process of ethnobotanical phytopharmaceuticals and how in silico methods are becoming increasingly useful for sustainable drug discover

Observation of quantum entanglement with top quarks at the ATLAS detector

Entanglement is a key feature of quantum mechanics with applications in fields such as metrology, cryptography, quantum information and quantum computation. It has been observed in a wide variety of systems and length scales, ranging from the microscopic to the macroscopic. However, entanglement remains largely unexplored at the highest accessible energy scales. Here we report the highest-energy observation of entanglement, in top–antitop quark events produced at the Large Hadron Collider, using a proton–proton collision dataset with a centre-of-mass energy of √s = 13 TeV and an integrated luminosity of 140 inverse femtobarns (fb)−1 recorded with the ATLAS experiment. Spin entanglement is detected from the measurement of a single observable D, inferred from the angle between the charged leptons in their parent top- and antitop-quark rest frames. The observable is measured in a narrow interval around the top–antitop quark production threshold, at which the entanglement detection is expected to be significant. It is reported in a fiducial phase space defined with stable particles to minimize the uncertainties that stem from the limitations of the Monte Carlo event generators and the parton shower model in modelling top-quark pair production. The entanglement marker is measured to be D = −0.537 ± 0.002 (stat.) ± 0.019 (syst.) for 340 GeV < mtt < 380 GeV. The observed result is more than five standard deviations from a scenario without entanglement and hence constitutes the first observation of entanglement in a pair of quarks and the highest-energy observation of entanglement so far

In-situ Raman spectroscopy study of Ru/TiO2 catalyst in the selective methanation of CO

Raman spectroscopic technique has been used to characterize a Ru/TiO2 catalyst and to follow in situ their structural changes during the CO selective methanation reaction (S-MET). For a better comprehension of the catalytic mechanism, the in-situ Raman study of the catalysts activation (reduction) process, the isolated CO and CO2 methanation reactions and the effect of the composition of the reactive stream (H2O and CO2 presence) have been carried out. Raman spectroscopy evidences that the catalyst is composed by islands of TiO2¿RuO2 solid solutions, constituting Ru¿TiO2 interphases in the form of RuxTi1 xO2 rutile type solid solutions. The activation procedure with H2 at 300 °C promotes the reduction of the RuO2¿TiO2 islands generating Ruo ¿Ti3+ centers. The spectroscopic changes are in agreement with the strong increase in chemical reactivity as increasing the carbonaceous intermediates observed. The selective methanation of CO proceeds after their adsorption on these Ruo ¿Ti3+ active centers and subsequent C-O dissociation throughout the formation of CHx/CnHx/CnHxO/CHx-CO species. These intermediates are transformed into CH4 by a combination of hydrogenation reactions. The formation of carbonaceous species during the methanation of CO and CO2 suggests that the CO presence is required to promote the CO2 methanation. Similar carbonaceous species are detected when the selective CO methanation is carried out with water in the stream. However, the activation of the catalysts occurs at much lower temperatures, and the carbon oxidation is favored by the oxidative effect of water.Peer Reviewe

Assessing extinction-risk of endangered plants using species distribution models: a case study of habitat depletion caused by the spread of greenhousesBenito, B.M

The species distribution models (SDMs) are useful tools for investigating rare and endangered species as well as the environmental variables affecting them. In this paper, we propose the application of SDMs to assess the extinction-risk of plant species in relation to the spread of greenhouses in a Mediterranean landscape, where habitat depletion is one of the main causes of biodiversity loss. For this purpose, presence records of the model species (Linaria nigricans, a endemic and threatened species) and the greenhouses, a dataset of environmental variables, and different only presence-based modelling algorithms (Bioclim, Domain, GARP, MaxEnt and ENFA) were used to build SDMs for L. nigricans as well as for greenhouses. To evaluate the models a modified approach of the area-under-curve ROC was applied. Combining the most accurate models, we generated an extinction-risk model of L. nigricans populations, which enabled us to assess the sustainability of the most threatened populations. Our results show that is possible to model greenhouses spreading as a “biological invasion”. The procedure explained and used in this work is quite novel, and offers an objective spatial criterion intended for the management of natural resources and for the conservation of the biodiversity in areas threatened by habitat depletion processes as particular as greenhouses expansion

Metal micromonoliths for the cleaning of H2 by means of methanation reactions

Esta versión es la versión aceptada por la revista en la que aparecen resaltados los cambios hechos en el documento original por sugerencia de los revisores.The present manuscript presents for the first time the structuring of a Ru/TiO2 catalyst that was achieved by means of the washcoating procedure using homemade metal micromonoliths (Fecralloy®) of 1330 cpsi. For this, an optimized formulation of the slurried catalyst as well as a reproducible protocol for the coating of the micromonoliths were successfully achieved. The obtained structured systems were tested in the selective CO methanation reaction and the effect of different variables over the catalytic performance were analyzed such as the amount of loaded catalyst in the micromonoliths, the temperature of reaction, the space velocity, and the amount of CO and H2 within the feed-stream. The study of all of these parameters allowed to establish optimal conditions to maximize the performance of the structured Ru/TiO2 catalyst and subsequently, this was tested under those cited conditions in long-term tests (~375 h), including shut-down/start-up cycles, aiming to evaluate its catalytic stability. The system presented a considerable stability along the different test without loss of catalytic activity, being specially remarkable its resistance to the inclusion of shut-down/start-up cycles. Therefore, this study lays the foundations for future development of more sophisticated structured systems for the selective CO methanation based on the structuring strategy proposed.Universidad de Jaén a través del programa “Acci´on 6 del Plan de Apoyo a la Investigaci´on de la Universidad de Ja´en (2017-2019)” para el contrato de O.H. LagunaMinisterio de Economía y Competitividad a través de la beca CTQ2015-73901-JIN, cofinanciada con fondos FEDER de la Unión Europea.Ministerio de Economía y Competitividad a través de la financiación del proyecto RTI2018-096294-B-C33, cofinanciado con fondos FEDER de la Unión Europea.Junta de Andalucía a través de su apoyo económico a la unidad TEP10

Effect of noble metal addition over active Ru/TiO2 catalyst for CO selective methanation from H2 rich-streams

Selective CO methanation from H2-rich stream has been regarded as a promising route for deep removal of low CO concentration and catalytic hydrogen purification processes. This work is focused on the development of more efficient catalysts applied in practical conditions. For this purpose, we prepared a series of catalysts based on Ru supported over titania and promoted with small amounts of Rh and Pt. Characterization details revealed that Rh and Pt modify the electronic properties of Ru. The results of catalytic activity showed that Pt has a negative effect since it promotes the reverse water gas shift reaction decreasing the selectivity of methanation but Rh increases remarkably the activity and selectivity of CO methanation. The obtained results suggest that RuRh-based catalyst could become important for the treatment of industrial-volume streams.Financial support for this work has been obtained from the Spanish Ministerio de Ciencia, Innovación y Universidades (Grant: RTI2018-096294-B-C33) and Junta de Andalucía project with reference US-1263288, both programs being co-funded by the European Union FEDER.Peer reviewe

Las plantas medicinales en el inventario español sobre los conocimientos Tradicionales relativos al patrimonio natural y a la biodiversidad

En las últimas décadas las organizaciones internacionales han puesto de manifiesto la importancia de los conocimientos ecológicos tradicionales para la conservación y el uso sostenible de la diversidad biológica, como se refleja en el Convenio sobre la Diversidad Biológica (CBD 1992). En España, el marco jurídico que recoge las normas y recomendaciones de esta estrategia es la Ley de Patrimonio Natural y Biodiveresidad 42/2007 que establece la creación del Inventario Español de Conocimientos Tradicionales (IECT) relevantes para la conservación y el uso sostenible de la biodiversidad y geodiversidad. Desde hace más de un año un equipo de más de 60 investigadores, incluyendo botánicos, zoólogos, antropólogos, ecólogos y geólogos de más de 20 centros de investigación y universidades del estado español, están trabajando en el IEDT, con el objetivo de recopilar y difundir la información publicada sobre los conocimientos tradicionales relativos a la flora, fauna, geodiversidad y el manejo de los ecosistemas