Moluscos del yacimiento paleontológico de "Lo Hueco" (Cretácico Superior, Cuenca, España): Implicaciones paleoambientales y secuenciales

In the exceptional site of "Lo Hueco" (Cuenca, Spain) more than 8500 macroremains of plants, invertebrates and vertebrates, including titanosaur sauropod dinosaurs, have been collected in a succession of Upper Cretaceous "Garumn" facies. This work describes the molluscs found together, interpreting their palaeoenvironmental and sequential meaning. The sample is comparatively scarce due to the urgency of the excavation, and to constraints of the preservational scenario, seemingly not ideal for the fossilization of carbonated remains. Thus, the absence of well preserved shells has motivated the use of open nomenclature. Bivalves are recorded by unarticulated marly mudstone moulds of Margaritifera sp., Anodonta sp., ?Corbicula sp. and Pisidium sp., and most gastropods by gypsum moulds of Faunus sp. This association indicates a typical freshwater palaeofauna, where the presence of Melanopsidae gastropods can suggest the sporadic influence of moderately brackish-water episodes. These data confirm previous palaeoenvironmental interpretations proposed for the site. Additionally, the presence of the terrestrial gastropod Palaeocyclophorus sp. in underlying beds with high proportion of vegetal terrestrial organic matter, and situated over an important erosive discordance, has allowed to locate the beginning of the depositional sequence of "Lo Hueco".En el excepcional yacimiento paleontológico de "Lo Hueco" (Cuenca, España) se han obtenido más de 8500 macrorrestos de plantas, invertebrados y vertebrados, incluyendo dinosaurios saurópodos titanosaurios, en una sección del Cretácico Superior en facies "Garumn". El presente trabajo describe los moluscos recogidos, interpretando su significado paleoambiental y secuencial. La muestra obtenida resulta relativamente reducida debido a la urgencia de la excavación, y a que las condiciones diagenéticas posiblemente no han favorecido la preservación de restos carbonatados. En consecuencia, la ausencia de conchas bien preservadas ha obligado a la utilización de nomenclatura abierta. Los bivalvos identificados se encuentran representados por moldes margosos desarticulados de Margaritifera sp., Anodonta sp., ?Corbicula sp. y Pisidium sp., y la mayoría de los gasterópodos por moldes de yeso de Faunus sp. Esta asociación corresponde a una típica paleofauna de agua dulce, en la que la presencia de gasterópodos melanópsidos parece sugerir la influencia esporádica de episodios de agua salobre. Estos datos confirman las interpretaciones paleoambientales previas propuestas para el yacimiento. Adicionalmente, la presencia del gasterópodo terrestre Palaeocyclophorus sp. en niveles infrayacentes con una elevada proporción de materia orgánica vegetal, situados sobre una importante discordancia erosiva, ha permitido localizar el inicio de la secuencia deposicional correspondiente a "Lo Hueco"

Bandgap behavior and singularity of the domain-induced light scattering through the pressure-induced ferroelectric transition in relaxor ferroelectric A(x)Ba(1-x)Nb(2)O(6) (A: Sr,Ca)

[EN] In this letter, we have investigated the electronic structure of A(x)Ba(1-x)Nb(2)O(6) relaxor ferroelectrics on the basis of optical absorption spectroscopy in unpoled single crystals with A = Sr and Ca under high pressure. The direct character of the fundamental transition could be established by fitting Urbach's rule to the photon energy dependence of the absorption edge yielding bandgaps of 3.44(1) eV and 3.57(1) eV for A = Sr and Ca, respectively. The light scattering by ferroelectric domains in the pre-edge spectral range has been studied as a function of composition and pressure. After confirming with x-ray diffraction the occurrence of the previously observed ferroelectric to paraelelectric phase transition at 4 GPa, the light scattering produced by micro-and nano-ferroelectric domains at 3.3 eV in Ca0.28Ba0.72Nb2O6 has been probed. The direct bandgap remains virtually constant under compression with a drop of only 0.01 eV around the phase transition. Interestingly, we have also found that light scattering by the polar nanoregions in the paraelectric phase is comparable to the dispersion due to ferroelectric microdomains in the ferroelectric state. Finally, we have obtained that the bulk modulus of the ferroelectric phase of Ca0.28Ba0.72Nb2O6 is B-0 = 222(9) GPa. Published by AIP Publishing.J.R.-F. acknowledges the Spanish MINECO for the Juan de la Cierva (IJCI-2014-20513) Program and Dr. Bayarjargal from the Goethe-Universitat Frankfurt for providing the CBN28 samples. This work was supported by Spanish MINECO under Grant No. MAT2016-75586-C4-1-P/2-P. The high pressure x-ray diffraction experiments were performed at MSPD beamline at ALBA Synchrotron (Project 2016021588) with the collaboration of ALBA staff.Ruiz-Fuertes, J.; Gomis, O.; Segura, A.; Bettinelli, M.; Burianek, M.; Muehlberg, M. (2018). Bandgap behavior and singularity of the domain-induced light scattering through the pressure-induced ferroelectric transition in relaxor ferroelectric A(x)Ba(1-x)Nb(2)O(6) (A: Sr,Ca). Applied Physics Letters. 112(4). https://doi.org/10.1063/1.5012111S112

Finitely fibered Rosenthal compacta and trees

We study some topological properties of trees with the interval topology. In particular, we characterize trees which admit a 2-fibered compactification and we present two examples of trees whose one-point compactifications are Rosenthal compact with certain renorming properties of their spaces of continuous functions.Comment: Small changes, mainly in the introduction and in final remark

The Effect of Impacts on the Martian Climate

Evidence for the presence of liquid water early in Mars history continues to accumulate. The most recent evidence for liquid water being pervasive early in Mars history is the discoveries of sulfate and gypsum layers by the Mars Exploration Rovers and Mars Express. However, the presence of liquid water at the surface very early in Mars history presents a conundrum. The early sun was most likely approximately 75% fainter than it is today. About 65-70 degrees of greenhouse warming is needed to bring surface temperatures to the melting point of water. To date climate models have not been able to produce a continuously warm and wet early Mars. This may be a good thing as there is morphological and mineralogical evidence that the warm and wet period had to be relatively short and episodic. The rates of erosion appear to correlate with the rate at which Mars was impacted thus an alternate possibility is transient warm and wet conditions initiated by large impacts. It is widely accepted that even relatively small impacts (approximately 10 km) have altered the past climate of Earth to such an extent as to cause mass extinctions. Mars has been impacted with a similar distribution of objects. The impact record at Mars is preserved in the abundance of observable craters on it surface. Impact induced climate change must have occurred on Mars

An XMM-Newton Study of the Bright, Nearby Supernova Remnant G296.1-0.5

We present a detailed study of the supernova remnant G296.1-0.5, performed using observations with the EPIC and RGS instruments of the XMM-Newton satellite. G296.1-0.5 is a bright remnant that displays an incomplete multiple-shell morphology in both its radio and X-ray images. We use a set of observations towards G296.1-0.5, from three distinct pointings of EPIC, in order to perform a thorough spatial and spectral analysis of this remnant, and hence determine what type of progenitor gave rise to the supernova explosion, and describe the evolutionary state of the SNR. Our XMM-Newton observations establish that the spectral characteristics are consistent across the X-ray bright regions of the object, and are best described by a model of the emission from a nonequilibrium ionization collisional plasma. The study reveals that the emission from the shell is characterized by an excess of N and an underabundance of O, which is typical of wind material from red supergiant (RSG) and Wolf-Rayet (WR) stars. Additionally, we have detected transient X-ray source 2XMMi J115004.8-622442 at the edge of the SNR whose properties suggest that it is the result of stellar flare, and we discuss its nature in more detail.Comment: 10 pages, 7 figures, 3 tables. Accepted for publication in Ap

Rasgos de personalidad y burnout en médicos de familia

ObjetivoInvestigar los rasgos de personalidad que podrían asociarse con puntuaciones altas en las escalas de burnout (Maslach Burnout Inventory) en médicos de atención primaria.DiseñoEstudio observacional, descriptivo, transversal.EmplazamientoNoventa y tres centros de atención primaria de la ciudad de Barcelona y las comarcas del norte de la provincia: Vallès Oriental, Vallès Occidental, Maresme, Osona, Bages y Berguedà (región sanitaria centro).MétodoEncuesta directa por entrevista personal o grupal a 528 médicos de atención primaria. Se administraron 3 cuestionarios: uno de datos sociodemográficos generales, el Maslasch Burnout Inventory (MBI) y el test de personalidad de Cattell 16 PF-5.ResultadosUn 40% de los encuestados presentaba algún síntoma de burnout sin diferencia entre sexos. De éstos, un 12,4% manifestaba niveles muy altos de «quemazón» profesional. Los sujetos con criterios de burnout obtuvieron puntuaciones significativamente diferentes en los rasgos de estabilidad, tensión y vigilancia y en la dimensión ansiedad.ConclusionesAlgunos rasgos de personalidad, como la baja estabilidad emocional, la tensión y la ansiedad, se asocian de manera significativa a puntuaciones altas de burnoutExisten algunas diferencias entre estos factores internos por sexo.ObjectiveWith this research we try to study personality traits that could be associated with high punctuation at burnout scales (Maslach Burnout Inventory) in primary care physicians.DesignObservational descriptive transversal studySetting93 primary care centres in Barcelona-city and the northern province's region: Vallès Oriental, Vallès Occidental, Maresme, Osona, Bages and Berguedà (centre sanitary region).MethodIndividual or collective direct interview to 528 primary care physicians. Three questioners were administrated: a sociodemographyc items one, the Maslach Burnout Inventory (MBI) and the Cattell personality test 16-PF.ResultsThe 40% of the interviewed physicians had some burnout symptom without any difference between sexes. The 12.4% of these ones showed very high burnout levels. Those subjects with burnout criteria punctuated different at stability, tension and vigilance traits and anxiety dimension.ConclusionSome personality traits like low stability, the tension and the anxiety are associated with high punctuation of burnout

Exploring the Design Space for Body Transformation Wearables to Support Physical Activity through Sensitizing and Bodystorming

Negative or disturbed body perceptions are often interwoven with people's physical inactivity. While wearables can support body perception changes (body transformation), the design space of body transformation wearables supporting physical activity remains narrow. To expand this design space, we conducted an embodied co-design workshop with users. Using conceptual and tangible sensitizing tools, we explored/reflected on bodily sensations at three moments of movement execution (before/during/after). Conceptual tools were used to evoke/reflect/capture past lived experiences, while tangible tools were used as ideation probes for sensory bodystorming. Two design concepts emerged, reflecting diverging approaches to body transformation wearables: one focused on reminders and movement correction; the other on sensory augmentation and facilitation. We reflect on how each facilitates useful representations of body sensations during movement, and present methodological recommendations for designing technology for sensory augmentation in this area. Finally, we propose a preliminary prototype based on our design concepts and discuss future steps

Determination of the high-pressure crystal structure of BaWO4 and PbWO4

We report the results of both angle-dispersive x-ray diffraction and x-ray absorption near-edge structure studies in BaWO4 and PbWO4 at pressures of up to 56 GPa and 24 GPa, respectively. BaWO4 is found to undergo a pressure-driven phase transition at 7.1 GPa from the tetragonal scheelite structure (which is stable under normal conditions) to the monoclinic fergusonite structure whereas the same transition takes place in PbWO4 at 9 GPa. We observe a second transition to another monoclinic structure which we identify as that of the isostructural phases BaWO4-II and PbWO4-III (space group P21/n). We have also performed ab initio total energy calculations which support the stability of this structure at high pressures in both compounds. The theoretical calculations further find that upon increase of pressure the scheelite phases become locally unstable and transform displacively into the fergusonite structure. The fergusonite structure is however metastable and can only occur if the transition to the P21/n phases were kinetically inhibited. Our experiments in BaWO4 indicate that it becomes amorphous beyond 47 GPa.Comment: 46 pages, 11 figures, 3 table

A large Venous-Arterial PCO2 Is Associated with Poor Outcomes in Surgical Patients

Background. This study evaluated whether large venous-arterial CO2 gap (PCO2 gap) preoperatively is associated to poor outcome. Method. Prospective study which included adult high-risk surgical patients. The patients were pooled into two groups: wide [P(v-a)CO2] versus narrow [P(v-a)CO2]. In order to determine the best value to discriminate hospital mortality, it was applied a ROC (receiver operating characteristic) curve for the [P(v-a)CO2] values collected preoperatively, and the most accurate value was chosen as cut-off to define the groups. Results. The study included 66 patients. The [P(v-a)CO2] value preoperatively that best discriminated hospital mortality was 5.0 mmHg, area = 0.73. Preoperative patients with [P(v-a)CO2] more than 5.0 mmHg presented a higher hospital mortality (36.4% versus 4.5% P = 0.004), higher prevalence of circulatory shock (56.8% versus 22.7% P = 0.01) and acute renal failure postoperatively (27.3% versus 4.5% P = 0.02), and longer hospital length of stays 20.0 (14.0–30.0) versus 13.5 (9.0–25.0) days P = 0.01. Conclusions. The PCO2 gap values more than 5.0 mmHg preoperatively were associated with worse postoperatively outcome

Variability and evolution of the optical polarization of a sample of gamma-ray blazars

We present a polarization variability analysis of a sample of 26 $\gamma$-ray blazars monitored by the Steward Observatory between 2008 and 2018 in the optical band. We investigate the properties and long-term variability of their optical polarization, searching for differences between blazar types. We observe that BL Lac objects are typically less polarized and less variable than flat spectrum radio quasars (FSRQs). Moreover, BL Lacs display a distribution of their polarization angle typically oriented in a preferential direction, contrary to the rather random distribution of FSRQs. For the latter blazar type, as well as those sources showing a bright stellar emission, we take into account the depolarizing effect introduced by the broad line region and the host galaxy on the measured polarization degree. In this sample we also observe that BL Lacs present an uncorrelated evolution of the flux and the polarization. Contrary, FSRQs show a correlation before the depolarization correction, that is lost however after considering this effect. In addition, we study the behaviour of the polarization angle, searching for angle rotations in its long-term evolution. We derive that the FSRQs studied here show rotations more frequently than BL Lac objects by a factor $\sim$1.5. During these periods we also observe a systematic decrease of the polarization fraction, as well as a marginal flux increase, not significant however to connect rotations with optical flares. We interpret these results within the extended shock-in-jet scenario, able to explain the overall features observed here for the polarization of the blazar sample.Comment: Accepted for publication in MNRA