4,292 research outputs found

    Aportaciones al conocimiento de la estructura del sinclinorio de Verín

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    Resumen] Los materiales precámbricos, ordovícicos y silúricos del Sinclinorio de Ver!n están afectados por una deformación polifásica, acompañada de un metamorfismo regional de presión intermedia-baja durante el hercínico. Los datos estructurales obtenidos indican una disposición subhorizontal para la esquistosidad primaria, en toda la sucesión metasedimentaria, antes de ser afectada por las fases posteriores. Este hecho, difiere de lo considerado anteriormente en el sentido de la existencia de una importante fase de deformación a comienzos del Silúrico, atestiguada por la existencia de una esquistosidad primaria en abanico, a escala del sinclinorio, afectando únicamente a los materiales presilúricos. La verticalización de la esquistosidad primaria en los flancos del sinclinorio, sus suaves buzamientos en el sector S de la zona de charnela central y el desarrollo de una esquistosidad de crenulación muy.penetrativa en el sector N de la misma, son hechos explicables teniendo en cuenta el papel que ha jugado el basamento granítico irregular y el macizo básico de Braganza su-oprayacente.[Abstract] The precambrian, ordovician and silurian materials outcropping in the Verín sinclyne have undergone the effects of a poliphase deformation during the Hercynian cycle. The deformation is synchronous with an intermediate low pressure type regional metamorphism. The existence of·a pre-silurian deformation phase is discarded. It is shown that the sttitude of the cleavages within the sinclyne is controlled by the irregular granitic basement and the overlying Braganza massi

    Gender bias in ecosystem restoration: from science to practice

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    The declaration of the United Nations Decade on Ecosystem Restoration 2020–2030 has established the need to focus on human rights in restoration initiatives, including gender equality. Although this goal raises a need to monitor gender biases on ecosystem restoration, we still lack basic gender information and evaluations on the current situation. The main purpose of this study is to analyze gender bias in ecosystem restoration covering three dimensions: research, outreach, and practice. We used scientific publications from the Restoration Ecology journal, mentions of these articles in Altmetric Explorer and Twitter, and projects from the Society for Ecological Restoration's database. First, we study gender bias among people leading ecosystem restoration initiatives in the three dimensions. Second, we assessed factors that could influence gender bias, including year, target ecosystem, and socioeconomic country development. Third, we analyzed whether the impact of scientific knowledge in society depends on the gender of the scientific team. Our results indicate that men were primary leaders in research, outreach, and practice initiatives in ecosystem restoration. There seems to be a trend over time toward equality in research, but gender inequality is still present in most types of ecosystems, with women leading more projects in more developed countries. The impact of scientific knowledge is independent of the author's gender, but research of male senior authors seems to reach society more easily. This broad perspective of inequality in the three dimensions can evolve toward gender equality, by applying gender approaches in restoration policies and initiatives. © 2022 Society for Ecological Restoration.Raw data is publicly available thanks to Web of Science, Altmetrics, Twitter and SER. Data and scripts used for the analysis are available via Figshare (Cruz‐Alonso et al. 2022 ). Funding: V.C.‐A.—Real Colegio Complutense postdoc fellowship; A.R.‐U.—Spanish State Research Agency through María de Maeztu Excellence Unit accreditation 2018–2022 (MDM‐2017‐0714); L.M.—Swiss National Science Foundation (PCEFP2_181115) and a Margarita Salas Postdoctoral Fellowship from Universidad de Alcalá; L.M.‐B.—Ministerio de Ciencia e Innovación (PID2019‐106806GB‐I00) and a Margarita Salas Postdoctoral Fellowship from Universidad de Alcalá; N.M.—predoctoral grant from Universidad de Alcalá; E.V.‐A.—European Commission (project SHOWCASE, H2020: 862480). We appreciate the support of the FIRE Foundation and the comments of M. Almaraz, M. Pajares, A. S. Moya, and D. Rohrer to improve the manuscript.Raw data is publicly available thanks to Web of Science, Altmetrics, Twitter and SER. Data and scripts used for the analysis are available via Figshare (Cruz‐Alonso et al. 2022 ). Funding: V.C.‐A.—Real Colegio Complutense postdoc fellowship; A.R.‐U.—Spanish State Research Agency through María de Maeztu Excellence Unit accreditation 2018–2022 (MDM‐2017‐0714); L.M.—Swiss National Science Foundation (PCEFP2_181115) and a Margarita Salas Postdoctoral Fellowship from Universidad de Alcalá; L.M.‐B.—Ministerio de Ciencia e Innovación (PID2019‐106806GB‐I00) and a Margarita Salas Postdoctoral Fellowship from Universidad de Alcalá; N.M.—predoctoral grant from Universidad de Alcalá; E.V.‐A.—European Commission (project SHOWCASE, H2020: 862480). We appreciate the support of the FIRE Foundation and the comments of M. Almaraz, M. Pajares, A. S. Moya, and D. Rohrer to improve the manuscript

    Heuristics in creating and solving probability problem statements

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    III Congreso Internacional Virtual de Educación Estadística (CIVEEST), 21-24 febrero de 2019. [www.ugr.es/local/fqm126/civeest.html]La resolución de problemas es una tarea cognitiva de vital importancia en el aprendizaje de las matemáticas, ya que permite desarrollar el razonamiento matemático. En este trabajo se ha planteado una experiencia a través del campus virtual universitario para la que se solicitó al alumnado del tercer curso del Grado en Maestro/a en educación primaria que planteasen y resolviesen un problema de probabilidad adaptado a nivel de 6º de primaria. El objetivo del estudio ha sido averiguar qué heurísticos y técnicas son puestas en práctica por los alumnos en la creación y resolución de problemas adaptados a este nivel, así como la detección de patrones de actuación en dicho proceso. Durante el análisis se ha detectado el uso de varios heurísticos (entre ellos se encuentran el tanteo, trabajar marcha atrás o el uso de gráficos) encontrando, además, un patrón interesante que se ve repetido en varias ocasiones.Problem-solving is a very important cognitive task in the process of learning mathematics, as it allows developing mathematical reasoning. in this work, an experience has been carried out through a university online Campus. Students in the third year of the Bachelor’s Degree of Primary Education participated in the experience. They were asked to raise and solve a probability problem adapted to 6th level of primary education. The aim of the study was to find out which heuristics and techniques were used by the students for creating and solving problems adapted to a specific primary level, as well as the detection of action patterns in this process. During the analysis the use of several heuristics has been detected (among them are trial-and-error, work backwards or the use of graphics) finding an interesting pattern that was repeated several times

    Stratigraphy and structure of the Punta Negra Anticline. Implications on the structural evolution of the Argentine Precordillera

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    The Punta Negra Anticline is a thrust-related fold, several kilometres wide, located at the front of the Argentine Central Precordillera. A stratigraphic succession including Ordovician, Silurian and Devonian rocks is exposed in its core, instead of a Devonian and Carboniferous succession as previously had been considered. The Punta Negra Anticline also involves a Tertiary sequence displaying syntectonic uncon­formities in the transition between the Albarracín and Mogna formations, recording the timing of thrusting and folding at the front of the Central Precordillera. This anticline folds thrust systems detached at the Silurian and Devonian shales, which we interpret as pre-Andean (Gondwanan) thrusts in this part of the Precordillera. The pre-Andean age of these thrusts is also consistent with their truncation by Tertiary subvolcanic intrusive bodies that predate the onset of the Andean deformation in the Punta Negra area. Moreover, the size and structural style of the Punta Negra Anticline, Andean in age, is in contrast with the other folds of the Central Precordillera, whose sizes do not exceed the hectometric scale and can be related to Gondwanan thrusting. This implies an Andean deeper thrust, probably detached at the bottom of the Cambrian succession.El Anticlinal de Punta Negra es un pliegue de varios kilómetros de anchura, relacionado con el cabalgamiento frontal de la Precordillera Central Argentina. Previamente se había considerado que las rocas más antiguas expuestas en dicho anticlinal eran devónicas, pero la sucesión estratigráfica que aflora en su charnela incluye también rocas ordovícicas y silúricas. El Anticlinal de Punta Negra también invo­lucra una sucesión de edad terciaria, la cual muestra discordancias sintectónicas en el tránsito entre las formaciones Albarracín y Mogna, proporcionando información sobre la edad y evolución de dicha estructura. El anticlinal pliega cabalgamientos despegados en las pizarras silúricas y devónicas, que interpretamos como de edad pre-Andina (Gondwánicos). Estos cabalgamientos están cortados por cuerpos intru­sivos subvolcánicos que son anteriores a la edad propuesta para el comienzo de la deformación Andina en el área de Punta Negra. Además, el tamaño y estilo del Anticlinal de Punta Negra, de edad Andina, contrastan con el resto de los pliegues de la Precordillera Central, cuyos tamaños no exceden de centenares de metros y pueden ser atribuidos a la deformación Gondwánica. Ello implica un cabalgamiento mas profundo en el Anticlinal de Punta Negra, probablemente enraizado en la base de la sucesión cámbrica

    Fresh perspectives for classic forest restoration challenges

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    Restoration ecology is a young scientific discipline whose limitations can compromise the recovery of ecosystem biodiversity and functions. Specifically for limitations on forest restoration, we first recommend considering measures prior to land use changes to deal with the common lack of efforts to anticipate and plan restoration. Second, we suggest using multiple references in restoration planning to avoid simplified reference characterization, and we advise assessing ecosystem recovery with indicators that better incorporate ecosystem complexity in recovery assessments. Finally, we propose initiatives to encourage scientific communication outside academia to diminish the communication gap between scientists and practitioners. © 2019 Society for Ecological RestorationA.R.U. was funded by Environmental Fellowship Programme of Tatiana Pérez de Guzmán el Bueno Foundation (2016) and María de Maeztu excellence accreditation (MDM-2017-0714) from the Spanish Government; V.C.A. by REMEDINAL4 (Madrid Government, TE-CM S2018/EMT-4338); Z.R. by the LafargeHolcim, FIRE Foundation, and UAH partnership; and L.M.B. by the FPI Fellowship (BES-2015-075276) from the Spanish Government

    Integral Field Spectroscopy based H\alpha\ sizes of local Luminous and Ultraluminous Infrared Galaxies. A Direct Comparison with high-z Massive Star Forming Galaxies

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    Aims. We study the analogy between local U/LIRGs and high-z massive SFGs by comparing basic H{\alpha} structural characteristics, such as size, and luminosity (and SFR) surface density, in an homogeneous way (i.e. same tracer and size definition, similar physical scales). Methods. We use Integral Field Spectroscopy based H{\alpha} emission maps for a representative sample of 54 local U/LIRGs (66 galaxies). From this initial sample we select 26 objects with H{\alpha} luminosities (L(H{\alpha})) similar to those of massive (i.e. M\ast \sim 10^10 M\odot or larger) SFGs at z \sim 2, and observed on similar physical scales. Results. The sizes of the H{\alpha} emitting region in the sample of local U/LIRGs span a large range, with r1/2(H{\alpha}) from 0.2 to 7 kpc. However, about 2/3 of local U/LIRGs with Lir > 10^11.4 L\odot have compact H{\alpha} emission (i.e. r1/2 < 2 kpc). The comparison sample of local U/LIRGs also shows a higher fraction (59%) of objects with compact H{\alpha} emission than the high-z sample (25%). This gives further support to the idea that for this luminosity range the size of the star forming region is a distinctive factor between local and distant galaxies of similar SF rates. However, when using H{\alpha} as a tracer for both local and high-z samples, the differences are smaller than the ones recently reported using a variety of other tracers. Despite of the higher fraction of galaxies with compact H{\alpha} emission, a sizable group (\sim 1/3) of local U/LIRGs are large (i.e. r1/2 > 2 kpc). These are systems showing pre-coalescence merger activity and they are indistinguishable from the massive high-z SFGs galaxies in terms of their H{\alpha} sizes, and luminosity and SFR surface densities.Comment: Accepted for publication in A&A. (!5 pages, 7 figures, 2 tables

    Roman mining works and gold ore deposits in the San Pedro de Olleros sector (El Bierzo, León)

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    [Abstract] The gold mining in the Bierzo Region, NW Spain had great importance, not only in the well known Las Médulas site, but also in the north sector of El Bierzo Basin, (San Pedro de Olleros Valle de Finolledo). This work have recognised the roman exploitation sites, differentiating the fertile facies within the tertiary sequences. Although no data about ages have still found, an approach to the tectonosedimentary evolutive history is carried out, taking into account the geometry and characteristics of the deposits[Abstract] The gold mining in the Bierzo Region, NW Spain had great importance, not only in the well known Las Médulas site, but also in the north sector of El Bierzo Basin, (San Pedro de Olleros -Valle de Finolledo). This work have recognised the roman exploitation sites, differentiating the fertile facies within the tertiary sequences. Although no data about ages have still found, an approach to the tectonosedimentary evolutive history is carried out, taking into account the geometry and characteristics of the deposit

    On the existence of a compact generator on the derived category of a noetherian formal scheme

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    In this paper, we prove that for a noetherian formal scheme X, its derived category of sheaves of modules with quasi-coherent torsion homologies D_qct(X) is generated by a single compact object. In an appendix we prove that the category of compact objects in D_qct(X) is skeletally small.Comment: 13 page

    Influencia de la espesura de un pinar albar (Sistema Central, España) en la disponibilidad de luz y agua en el sotobosque, y la supervivencia de robles plantados en su interior

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    Information of tree-nurse shelterwood effects on survival of underplanted seedlings is particularly scant in Mediterranean forest ecosystems. To study light and water resources availability and survival associated to overstory density, two-year-old seedlings of Quercus petraea (Matt.) Liebl. (sessile oak) and Quercus pyrenaica Willd. (pyrenean oak) were planted in the understory of an even-aged Scots pine (Pinus sylvestris L.) plantation located in central Spain, which had been previously assigned to three density treatments: uncut, 33% thinned and 50% thinned of the original density, each replicated four times. Soil moisture was measured with a TDR during the first growing season after planting. Light conditions were estimated by hemispherical photography. Survival was measured at the end of the first growing season in the field and at the beginning of the next two growing seasons. The reduction in density after thinning had a positive effect on light availability and on near-surface soil moisture. Pyrenean oak had higher survival rates than sessile oak, which showed similarly high mortality rates in all three overstory treatments. Thinning had a positive effect on the survival of pyrenean oak, though irrespective of the intensity. Overall, these results point to the necessity to reduce canopy tree density in Mediterranean mountain pinewoods before carrying out enrichment plantations beneath.Con el fin de estudiar el efecto de la espesura de la cubierta forestal en la disponibilidad de luz y agua para las plantas y su supervivencia, se plantaron brinzales de dos savias de Quercus petraea (Matt.) Liebl. (roble albar) y Quercus pyrenaica Willd. (melojo) en el interior de un pinar de Pinus sylvestris L. (pino albar) situado en el NE de la provincia de Madrid sometido previamente a tres tratamientos: clara del 33% de la densidad original, clara del 50% y ausencia de clara. Se midió la humedad volumétrica del suelo con un TDR y la disponibilidad de luz en el sotobosque por medio de fotografias hemisféricas. La supervivencia se midió al final del primer año y al comienzo del verano de los dos años siguientes. La reducción de la densidad del dosel incrementó la luz disponible en el sotobosque, la humedad de los primeros 10 cm de suelo y la supervivencia de las plantas de melojo, aunque no se apreció un efecto diferente segun la intensidad de la clara aplicada. La mortalidad de las plantas de roble albar fue elevada en todos los tratamientos, y superior a la del melojo. Estos resultados apuntan a la necesidad de reducir la espesura del pinar albar en la zona de estudio antes de llevar a cabo plantaciones con melojo en su interior

    Evolución costera de la desembocadura del Guadalquivir en los últimos 6000 años (SW de España)

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    3 páginas, 2 figuras, 5 referencias.Since the last Holocene sea level rise, about 6,900 yr BP, a series of depositional littoral landforms has been generated at the outlet of the Guadalquivir river, with progradation along the predominant longshore drift (towards the east). The littoral spit systems mapped constitute fur progradation phases. The first is dated between the Flandrian maximum (6,900 yr BP) and 4,500 yr BP; the second between 4,200-3,900 yr BP and 2,700-2,600 yr BP; the third between 2,300 yr BP and 1,100 yr BP; and the fourth between 1,000 yr BP and the present. There were separations of successive erosional phases between 4,500-4,200 yr BP, 2,600-2,300 yr BP and, 1,100-1,000 yr BP. Thus, cycles of higher sedimentation are established, with a slight fall and then stability of sea level. Littoral barrier constructions dominate, with the genesis of extensive tidal flats that decrease the size of the estuaries. These sedimentary phases are interrupted by rapid rises in sea level lasting from 100 to 300 years, when the previously constructed littoral barriers are eroded. The cliffs retreat, causing migration inland of dunar constructions, with frequent overlapping layers. Marine influence within the estuaries in creases.Este trabajo ha sido subvencionado por los proyectos coordinados de la DGICYT PB91-0622-C03-0 1 y PB94-1090-C03-0l. Es una contribución al IGCP-367.Peer reviewe
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