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19 páginas.- 5 figuras. 2 tablas.- 50 referencias.- Supplemental information for this article can be found online at http://dx.doi.org/10.7717/peerj.10994#supplemental-information. ; oils are highly heterogeneous and support highly diverse microbial communities. Microbial extracellular enzymes breakdown complex polymers into small assimilable molecules representing the limiting step of soil organic matter mineralization. This process occurs on to soil particles although currently it is typically estimated in laboratory aqueous solutions. Herein, estimates of microbial extracellular enzyme activity were obtained over a broad range of temperatures and water availabilities frequently observed at soil upper layers. A Pseudomonas strain presented optimum extracellular enzyme activities at high water activity whereas a desiccation resistant bacterium (Deinococcus) and a soil thermophilic isolate (Parageobacillus) showed optimum extracellular enzyme activity under dried (i.e., water activities ranging 0.5-0.8) rather that wet conditions. Different unamended soils presented a distinctive response of extracellular enzyme activity as a function of temperature and water availability. This study presents a procedure to obtain realistic estimates of microbial extracellular enzyme activity under natural soil conditions of extreme water availability and temperature. Improving estimates of microbial extracellular enzyme activity contribute to better understand the role of microorganisms in soils. ; This study was supported by funding through projects from the Spanish Ministry of Economy and Competitiveness (CGL2014-58762-P) and the Regional Government of Andalusia (RNM2529 and BIO288). These projects have been cofunded by FEDER funds. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript ; Peer reviewed

5 páginas.- 2 figuras.- 18 referencias ; Halogenated compounds are environmental pollutants toxic to humans and wildlife. Certain microorganisms degrade these halogenated compounds. However, little is known about the potential of microorganisms in bioremediation under extreme conditions, specifically in arid and semi-arid soils frequently exposed to high temperatures and desiccation periods. Arid and semi-arid environments and deserts make up vast areas of Earth's landmass. To investigate the degradation of 2-chlorophenol (2-CP) in soils as a function of temperature and water availability, three bacterial species were tested, two soil mesophiles of the genus Rhodococcus, R. opacus and R. erythropolis, and a soil thermophilic isolate, Parageobacillus thermoglucosidasius. Degradation trials in soil samples with these species were performed over a range of water activity from 1 to 0.4. At their optimum growth temperature, R. opacus showed maximum 2-CP degradation at water activity 0.9 sharply decreasing when lowering water activity. Nevertheless, the Parageobacillus isolate (optimum growth temperature 60°C) showed maximum 2-CP degradation rates at water activity 0.5 which represented highly desiccating conditions. Parageobacillus degradation of 2-CP was very low at water activity above 0.9. Thus, biodegradation of 2-CP in soils is possible even under arid conditions although different microbial species might be involved in this task depending on the interactions of abiotic factors and the diversity of microbial communities in soils. These results contribute to understand the potential biodegradation of specific halogenated compounds in the environment which is of great relevance to comprehend the fate of halogenated pollutants (i.e., 2-CP) in deserts, arid and semi-arid soils. ; This study was supported through funding from the Spanish Ministry of Economy and Competitiveness (CGL2014-58762-P; PCIN2016-129) and the Regional Government of Andalusia (RNM2529). These projects have been cofunded by FEDER funds. EM acknowledges funding through a Fullbright fellowship. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). ; Peer reviewed

Hoy en día, adoptar un enfoque organizacional de prácticas sostenibles para fomentar el uso responsable de los recursos puede representar una ventaja competitiva para las empresas, quienes así pueden mantener los costos bajos y la reputación alta. Un ejemplo de empresa que adopta este enfoque es Petróleos Mexicanos (PEMEX). Por eso, para esta investigación se realizó un análisis de su estructura de gestión externa –con base en la información proporcionada en su página web–, la cual incluye en sus Grupos de Interés a comunidades indígenas, sociedad civil, gobierno, medios de comunicación, proveedores y clientes. La evaluación del desempeño de la organización en cuanto a su relación con los grupos de interés relevantes se realizó con los informes proporcionados por la empresa anualmente, utilizando una matriz que incluye los resultados obtenidos en cada año en materia de gestión de grupos de interés. Los resultados muestran una tendencia decreciente de la empresa en la inversión en prácticas socialmente responsables, lo cual contradice la justificación de dicha inversión para promover y potenciar la ventaja competitiva de la empresa. ; Nowadays, adopting an organizational approach focused on sustainable practices aimed at promoting the responsible use of resources can represent a competitive advantage for companies, which can thus keep costs low and reputation high. An example of a company that adopts this approach is Petróleos Mexicanos (PEMEX). For this research, an analysis of the external management structure of the company –whose Interest Groups includes indigenous communities, civil society, government, media, suppliers and customers— was carried out based on the information provided on its website. The evaluation of the organization's performance in terms of its relationship with relevant stakeholders includes the annual reports provided by the company, using a matrix that includes the results obtained each year in terms of stakeholder management. The results show a decreasing tendency of the company on its ...

Purification of methane from other light hydrocarbons in natural gas is a topic of intense research due to its fundamental importance in the utilization of natural gas fields. Porous materials have emerged as excellent alternative platforms to conventional cryogenic methodologies to perform this task in a cost- and energy-efficient manner. Here we report a new family of isoreticular chiral MOFs, prepared from oxamidato ligands derived from natural amino acids L-alanine, L-valine and L-leucine, where, by increasing the length of the alkyl residue of the amino acid, the charge density of the MOF's channels can be tuned (1 > 2 > 3), decreasing the adsorption preference towards methane over light hydrocarbons thus improving this purification process. The validity of our rational design strategy has been proved by a combination of single-component adsorption isotherms, adsorption kinetics of CH4, C2H6, C3H8 and n-C4H10, and breakthrough experiments of binary CH4/C2H6 and CH4/C3H8 mixtures. ; This work was supported by the mineco (Spain) (Projects CTQ2013-46362-P, MAT2013-45008-P, MAT2016-81732-ERC, CTQ2016-75671-P and Excellence Unit "Maria de Maeztu" MDM-2015-0538), the Generalitat Valenciana (Spain) (Project PROMETEOII/2014/070, PROMETEOII/2014/004) and the Ministero dell'Istruzione, dell'Università e della Ricerca (Italy). T. G. and M. M. thank the Universitat de València and the mineco for predoctoral contracts. Thanks are also extended to the Ramón y Cajal Program (E. P. and E. V. R.-F. (RYC-2012-11427)). B. S. and J. G. acknowledge the financial support of the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement no. 335746, CrystEng-MOF-MMM.

La valoración del daño o perjuicio estético que ocasionan las cicatrices resultantes de accidentes de tráfico es una tarea no exenta de un gran componente de subjetividad. Presentamos un estudio de la valoración que de cuatro cicatrices, resultantes de sendos accidentes de tráfico, siguiendo las reglas de utilización de la tabla VI del Sistema para la valoración de los daños y perjuicios causados a las personas en accidentes de circulación (RD Legislativo 8/2004), han efectuado tres colectivos encuestados de diferentes procedencias: "jurídico" (Magistrados-Jueces y Jueces, Fiscales, abogados con ejercicio profesional en el ámbito de compañías de seguros o en el ámbito privado y estudiantes de la Escuela de Práctica Jurídica), "peritos médicos" (médicos forenses y médicos valoradores del daño corporal) y "resto de población" (estudiantes universitarios de Bellas Artes, sanitarios no médicos y otros estudiantes universitarios). Se han recogido 448 encuestas procedentes de estos tres colectivos en las que puntuaban el daño estético siguiendo la tabla VI. Se ha utilizado una metodología descriptiva y un análisis estadístico con pruebas no paramétricas. Se han encontrado diferencias estadísticamente significativas entre las valoraciones del perjuicio estético realizadas por los tres colectivos profesionales sometidos a encuesta: jurídico, peritos médicos y resto de población, al nivel de significación de α = 0.05. Los peritos médicos (médicos forenses y médicos valoradores del daño corporal) han valorado las cicatrices muy por debajo del colectivo jurídico, y éste a su vez, algo por debajo del resto de población. ; The assessment of damage or disfigurement caused by scars resulting from accidents is a task that inevitably involves a certain degree of subjectivity. We present a study of the assessment of four scars resulting from traffic accidents, according to the rules of use of Table VI of the system for the assessment of damages caused to people in traffic accidents (RDL 8/2004). The assessment was carried out by three groups of different origins: "legal professionals" (Judges, prosecutors, lawyers from the area of insurance companies or the private sector and students of the School of Legal Practice), "medical experts" (forensic doctors and doctors of the assessment of bodily harm) and other members of the population (students of fine art, other healthcare staff who are not doctors and other university students). 448 surveys were collected in from the three groups in which they gave a numerical value to the aesthetic damage based on Table VI. We used a descriptive methodology and statistical analysis using nonparametric tests. Significant statistical differences between the assessments of aesthetic damage carried out by the three professional groups in the survey were found: legal, medical experts and other members of the population, were found with a level of significance of α = 0.05. The medical experts (forensic doctors and medical assessors of bodily harm) rated the scars well below the level of the legal experts and at the same time they rated them below the level of the rest of the population.

The hydrogenation of nitroarenes to produce the corresponding amines using dihydrogen as reducing agent has an important industrial role, since it allows to obtain important added-value products. This reaction needs the help of a catalyst to proceed. Many catalysts have been already tested and studied. Most of them are based on noble metals supported on metal oxides. These catalysts perform well, but they are expensive and thus, alternative systems are needed. In this context, cobalt-based catalysts have emerged as adequate alternatives, despite cobalt nanoparticles per se are not very active for this reaction. A way to improve the catalytic activity of cobalt nanoparticles is by supporting them on a support with functional groups that are able to change their intrinsic properties and to enhance their catalytic properties. In this sense, N-containing carbons are promising candidates to be used as support, since nitrogen functionalities may modify the catalytic properties of cobalt. In this work, cobalt nanoparticles supported on N-doped activated carbons have been prepared and studied as catalysts for the hydrogenation of 1-chloro-4-nitrobencene to the corresponding chloro-aniline. It is demonstrated that the catalytic activity is enhanced by the presence of nitrogen species in the support. When the temperature of the catalyst activation treatment (reduction under flowing hydrogen) is increased, the catalytic activity increases drastically in the presence of nitrogen functionalities on the support. The catalysts have been characterised by transmission electron microscopy (TEM), temperature-programmed reduction (TPR), X-ray diffraction, X-ray photoelectron spectroscopi (XPS) and N2 adsorption at 77 K. It has been found that the enhanced catalytic activity was due to two different factors, namely the interaction of the cobalt particles with the nitrogen functional groups (forming Co4N), and the development of mesopores in the support during the activation process that increases the accessibility of reactants to the active sites. ; Authors acknowledge financial support by MINECO (Spain) through the projects MAT2017-86992-R and MAT2016-80285-P and the European Union for the project "eForFuel", grant agreement 763911. J. C. S. R. would like to thank the Spanish Ministry of Science and Innovation for financial support through the Ramón y Cajal Program, Grant: RYC-2015-19230 J. C. S. R. would also like to thank Junta de Andalucía for financial support through the projects PY18-RE-0012 and IE18_0047_FUNDACIÓN LOYOLA.

Una de las actividades de mayor importancia en la medicina forense práctica es la valoración del daño corporal. Dentro de la misma, en ocasiones, el médico forense se enfrenta a la difícil tarea de tener que valorar el daño o perjuicio estético que ocasionan cicatrices resultantes de agentes externos, valoración no exenta de un gran componente de subjetividad. Presentamos un estudio de la valoración que de cuatro cicatrices, resultantes de sendos accidentes de tráfico, han efectuado médicos forenses de los Institutos de Medicina Legal de Cataluña, Alicante y Galicia siguiendo las reglas de utilización de la tabla VI del Sistema para la valoración de los daños y perjuicios causados a las personas en accidentes de circulación (RD Legislativo 8/2004).Se ha utilizado una metodología descriptiva (medidas de tendencia central, de dispersión y de forma) y un análisis estadístico con pruebas no paramétricas. Se han obtenido puntuaciones medias en el Instituto de Medicina Legal de Cataluña en las cuatro cicatrices sometidas a valoración inferiores a las del Instituto de Medicina Legal de Alicante y del Instituto de Medicina Legal de Galicia. No se han encontrado diferencias entre las medidas de tendencia central en las valoraciones efectuadas por los médicos forenses de los tres Institutos de Medicina Legal al nivel de significación utilizado de a = 0.05 para los casos B y C mientras que para los casos A y D se han hallado diferencias estadísticamente significativas entre las medianas de las valoraciones efectuadas por los médicos forenses de los IML de Cataluña, Alicante y Galicia. ; One of the most important activities in forensic practice is the assessment of bodily harm. Within this field, the medical examiner sometimes faces the difficult task of having to assess damage or disfigurement resulting from scars caused by external agents. This assessment is not without a large element of subjectivity. We present a study of the assessment of four scars, from two separate traffic accidents, carried out by coroners from the Institute of Legal Medicine of Catalonia, Alicante and Galicia following the rules of Table VI using the System for assessing the damages caused to people in road accidents (RDL 8/2004). We used a descriptive methodology (measures of central tendency, dispersion and form) and statistical analysis with nonparametric tests. Mean scores were obtained at the Institute of Legal Medicine of Catalonia in the four inferior valuation of scars at the Legal Medicine Institute of Alicante and the Institute of Legal Medicine of Galicia. No differences were found between measures of central tendency of assessments by medical examiners of the three Institutes of Legal Medicine at the significance level of a = 0.05 used for cases B and C while for cases A and D statistically significant differences between the medians of the assessments made by the medical examiner of the Institute of Legal Medicine of Catalonia, Alicante and Galicia have been found.

Understanding/visualizing the established interactions between gases and adsorbents is mandatory to implement better performance materials in adsorption/separation processes. Here we report the unique behavior of a rare example of a hemilabile chiral three-dimensional metal–organic framework (MOF) with an unprecedented qtz-e-type topology, with formula CuII2(S,S)-hismox·5H2O (1) (hismox = bis[(S)-histidine]oxalyl diamide). 1 exhibits a continuous and reversible breathing behavior, based on the hemilability of carboxylate groups from l-histidine. In situ powder (PXRD) and single crystal X-ray diffraction (SCXRD) using synchrotron radiation allowed us to unveil the crystal structures of four different host–guest adsorbates (Ar@1, N2@1, CO2@1, and C3H6@1), rationalize the breathing motion, and unravel the mechanisms governing the adsorption of these gases. Then this information was transferred to implement efficient separations of mixtures of industrial and environmental relevance, CO2/N2, CO2/CH4, and C3H8/C3H6, using 1 in packed columns as the stationary phase and dispersed in a mixed matrix membrane. ; This work was supported by the MINECO (Spain) (projects CTQ2016-75671-P, MAT2017-86992-R, and MAT-80285-P and Excellence Unit "Maria de Maeztu" MDM-2015-0538) and the Ministero dell'Istruzione, dell'Università e della Ricerca (Italy). M.M. and E.T. thank the MINECO, and R.B. thanks the MIUR (project PON R&I FSE-FESR 2014-2020) for predoctoral grants. Thanks are also extended to the "Programa post-Ramón y Cajal de la Universidad de Valencia (E.P.)", the "Fondo per il finanziamento delle attivita base di ricerca" (D.A.), and the "Atracció de talent-contractes postdoctorals de la Universitat de Valencia" and "Juan de la Cierva-Incorporación-2017" programs (J.F.-S.). E.P. acknowledges the financial support of the European Research Council under the European Union's Horizon 2020 research and innovation programme/ERC grant agreement no. 814804, MOF-reactors.

20 pages, 18 figures.-- et al. ; Baryon Acoustic Oscillations (BAOs) provide a "standard ruler" of known physical length, making it one of the most promising probes of the nature of dark energy (DE). The detection of BAOs as an excess of power in the galaxy distribution at a certain scale requires measuring galaxy positions and redshifts. "Transversal" (or "angular") BAOs measure the angular size of this scale projected in the sky and provide information about the angular distance. "Line-of-sight" (or "radial") BAOs require very precise redshifts, but provide a direct measurement of the Hubble parameter at different redshifts, a more sensitive probe of DE. The main goal of this paper is to show that it is possible to obtain photometric redshifts with enough precision (σz) to measure BAOs along the line of sight. There is a fundamental limitation as to how much one can improve the BAO measurement by reducing σz . We show that σz ~ 0.003(1 + z) is sufficient: a much better precision will produce an oversampling of the BAO peak without a significant improvement on its detection, while a much worse precision will result in the effective loss of the radial information. This precision in redshift can be achieved for bright, red galaxies, featuring a prominent 4000 Å break, by using a filter system comprising about 40 filters, each with a width close to 100 Å, covering the wavelength range from ~4000 to ~8000 Å, supplemented by two broad-band filters similar to the Sloan Digital Sky Survey u and z bands. We describe the practical implementation of this idea, a new galaxy survey project, Physics of the Accelerating Universe (PAU): http://www.ice.cat/pau, to be carried out with a telescope/camera combination with an etendue about 20 m2 deg2, equivalent to a 2 m telescope equipped with a 6 deg2 field of view camera, and covering 8000 deg2 in the sky in four years. We expect to measure positions and redshifts for over 14 million red, early-type galaxies with L > L* and i(AB) ~ 10–3 Mpc–3 h3 galaxies within the 9 Gpc3 h–3 volume to be sampled by our survey, ensuring that the error in the determination of the BAO scale is not limited by shot noise. By itself, such a survey will deliver precisions of order 5% in the dark-energy equation of state parameter w, if assumed constant, and can determine its time derivative when combined with future cosmic microwave background measurements. In addition, PAU will yield high-quality redshift and low-resolution spectroscopy for hundreds of millions of other galaxies, including a very significant high-redshift population. The data set produced by this survey will have a unique legacy value, allowing a wide range of astrophysical studies. ; This work was carried out in the framework of the PAU Consolider Collaboration, supported in part by the Spanish Ministry of Education and Science (MEC) through the Consolider Ingenio-2010 program, under project CSD2007-00060 "Physics of the Accelerating Universe (PAU)". Additional support comes from the Barcelona Supercomputer Center, as well as from the European Commission, the Spanish High Council for Scientific Research (CSIC), and the regional governments of Andalusia, Aragon, Catalonia, Madrid, and Valencia. ; Peer reviewed

Heterogeneous single-site catalysts consist of isolated, well-defined, active sites that are spatially separated in a given solid and, ideally, structurally identical. In this review, the potential of metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) as platforms for the development of heterogeneous single-site catalysts is reviewed thoroughly. In the first part of this article, synthetic strategies and progress in the implementation of such sites in these two classes of materials are discussed. Because these solids are excellent playgrounds to allow a better understanding of catalytic functions, we highlight the most important recent advances in the modelling and spectroscopic characterization of single-site catalysts based on these materials. Finally, we discuss the potential of MOFs as materials in which several single-site catalytic functions can be combined within one framework along with their potential as powerful enzyme-mimicking materials. The review is wrapped up with our personal vision on future research directions. ; S. M. J. Rogge, J. Hajek, and V. Van Speybroeck acknowledge the Fund for Scientific Research – Flanders (FWO), the Research Board of Ghent University (BOF) and BELSPO in the frame of IAP/7/05 for financial support. V. Van Speybroeck acknowledges funding from the European Union's Horizon 2020 research and innovation programme (consolidator ERC grant agreement no. 647755 – DYNPOR (2015–2020)). This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 641887 (project acronym: DEFNET). W. Dewitte and C. Caratelli are acknowledged for technical support with the figures. J. Gascon acknowledges funding from the European Union's 2020 research and innovation programme (ERC grant agreement no. 335746 – CrystEng-MOF-MMM) and from the Dutch Organization for Scientific Research (NWO, VIDI grant agreement 723.012.107 – MetMOFCat).