Comparación de la composición química de los metabolitos secundarios volátiles de cuatro plantas de la familia piperaceae obtenidos por destilación–extracción simultánea

Se estudiaron las composiciones de las fracciones volátiles obtenidas por destilación – extracción con solvente simultánea (DES), de las hojas de cuatro plantas de la familia Piperaceae: Piper marginatum Jacq, P. aduncum L., P. hispidum Sw. y Pothomorphe peltata L. Las fracciones fueron analizadas por cromatografía de gases acoplada a espectrometría de masas (GC-MS)

Bat functional traits associated with environmental, landscape, and conservation variables in Neotropical dry forests

Tropical dry forests are among the most threatened ecosystems worldwide. Bats' role in those ecosystems is critical because of multiple bat-mediated processes. Such processes are strongly related to bats' functional traits. However, it is poorly known which bat's functional traits could relate to variations in environmental conditions in tropical dry forests. In this study, we tested the hypotheses that bat functional traits would be significantly associated with landscape variables, climatic variables, and land-use intensity. For testing these hypotheses, we used data from phyllostomid and mormoopid bats captured in mist nets and data from non-phyllostomid insectivorous bat species registered by passive acoustic monitoring. We considered six functional traits for phyllostomid and mormoopid bats, and for non-phyllostomid insectivorous bats, we added two echolocation parameters. We measured five environmental variables, two of local climate (daily maximum temperature and wind speed) and three of landscape features (total area of water and closeness, probability of finding caves, and conservation status). The relationships between bat functional traits and environmental variables were evaluated using the RLQ and the fourth-corner analysis. We captured 360 individuals belonging to 14 species with mist nets (Phyllostomidae and Mormoopidae), and we identified 18 species and six sonotypes with acoustic sampling (Emballonuridae, Mormoopidae, Molossidae, Natalidae, Noctilionidae, and Vespertilionidae). We found that bats' functional traits related to environmental conditions were pulse structure, diet, vertical foraging stratification, and trophic level, although these relationships varied among bats' ecological roles. The hematophagous were related to water bodies' closeness, and animalivorous bats, mostly mormoopids, showed a relationship with the probability of finding caves. Insectivorous bats that mostly forage on the canopy and emit qCF calls were significantly related to more conserved sites, and bats that emit qCF pulses were significantly associated with less area covered by water. Our findings provide insights into how bat functional traits vary in their relationships with environmental conditions in harsh environments such as dry forests

Improving Scientific Knowledge of Mallorca Channel Seamounts (Western Mediterranean) within the Framework of Natura 2000 Network

The scientific exploration of Mallorca Channel seamounts (western Mediterranean) is improving the knowledge of the Ses Olives (SO), Ausias March (AM), and Emile Baudot (EB) seamounts for their inclusion in the Natura 2000 network. The aims are to map and characterize benthic species and habitats by means of a geological and biological multidisciplinary approach: high-resolution acoustics, sediment and rock dredges, beam trawl, bottom trawl, and underwater imagery. Among the seamounts, 15 different morphological features were differentiated, highlighting the presence of 4000 pockmarks, which are seafloor rounded depressions indicators of focused fluid flow escapes, usually gas and/or water, from beneath the seabed sediments. So far, a total of 547 species or taxa have been inventoried, with sponges, fishes, mollusks, and crustaceans the most diverse groups including new taxa and new geographical records. Up to 29 categories of benthic habitats have been found, highlighting those included in the Habitats Directive: maërl beds on the summits of AM and EB, pockmarks around the seamounts and coral reefs in their rocky escarpments as well as fields of Isidella elongata on sedimentary bathyal bottoms. Trawling is the main demersal fishery developed around SO and AM, which are targeted to deep water crustaceans: Parapenaeus longirostris, Nephrops norvegicus, and Aristeus antennatus. This study provides scientific information for the proposal of the Mallorca Channel seamounts as a Site of Community Importance and for its final declaration as a Special Area of Conservation

Posible efecto cardioprotector de Solanum sisymbriifolium LAM. (SOLANACEAE) en ratas hipertensas por Nω-Nitro-L-Arginina metilester.

"En este trabajose propone evaluar la potencial actividad cardioprotectora- antihipertensiva del extracto bruto de la raíz de S. sisymbriifolium en ratas con hipertensión inducida por el Nω-Nitro-L-arginina metilester (L-NAME). "CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Hidratos de gas marinos: ¿un recurso futuro de gas natural para Europa? M.

Los hidratos de gas son compuestos cristalinos donde una molécula de gas, principalmente metano, queda atrapada en una red de moléculas de agua en forma de hielo. La importancia de los hidratos de gas en la naturaleza es muy alta ya que constituye una fuente alternativa de energía y a su vez juegan un papel importante en el delicado equilibrio del clima a nivel global y en los riesgos geológicos en el ámbito marino. La acción COST MIGRATE está diseñada con el fin de integrar la experiencia de un gran número de grupos de investigación europeos y agentes del sector para promover el desarrollo de conocimientos multidisciplinarios sobre el potencial de los hidratos de gas como fuente de energía en Europa. Dos de los objetivos de esta acción son realizar un inventario europeo de hidratos de gas explotables y evaluar los riesgos ambientales. En este trabajo se muestran los principales indicios de hidratos de gas en los márgenes europeos incluida la Península Ibérica, con una primera aproximación sobre el espesor y situación de la zona de estabilidad de hidratos de gas en el margen Ibérico.Gas hydrates are crystalline compounds where a molecule of gas, mainly methane, is trapped in a cage of icewater molecules. The importance of gas hydrates in nature is very high because it is an alternative source of energy and play a major role in the delicate balance of the global climate and in the marine geological risks. MIGRATE COST action is designed to integrate the experience of a large number of European research groups and industrial players to promote the development of multidisciplinary knowledge on the potential of gas hydrates as energy resource in Europe. Two of the objectives of the action aim to estimate the European inventory of exploitable gas hydrates and to assess environmental risks. In this work we show the occurrences of gas hydrates described in European margins including the Iberian Peninsula, with a first approximation on the thickness and location of the area of stability of gas hydrates in the Iberian margin.COST Action ES1405 (MIGRATE)Versión del edito

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO