3,200 research outputs found
Presencia de laminación oblicua a gran escala en las turbiditas senoenses del flysch de los alrededores de la Pobla de Segur (prov. Lérida)
En un corte cerca de la Pobla de Segur (Pirineos meridionales), se encuentran unas capas con laminación cruzada a gran escala, de hasta 30 cm de espesor, en una formación de turbiditas del Cretáceo Superior. Estas capas tienen generalmente forma de cuña o lentejón y se caracterizan por poseer superficies netas de contacto en el techo y yacente. Sólo en pocos casos están cubiertas por un delgado intervalo de limolitas con ripples de corriente.La laminación cruzada tiene un buzamiento de 5 a 30° y está uniformemente inclinada, al igual que los flute-casts, en la misma dirección que la corriente. Estos últimos se encuentran en el yacente de las mencionadas capas o en la base de las turbiditas asociadas.Estas caracterÃsticas representan formas geométricas de dunas o barras originadas por un régimen de corriente menos intenso
Presencia de laminación oblicua a gran escala en las turbiditas senoenses del flysch de los alrededores de la Pobla de Segur (prov. Lérida)
En un corte cerca de la Pobla de Segur (Pirineos meridionales), se encuentran unas capas con laminación cruzada a gran escala, de hasta 30 cm de espesor, en una formación de turbiditas del Cretáceo Superior. Estas capas tienen generalmente forma de cuña o lentejón y se caracterizan por poseer superficies netas de contacto en el techo y yacente. Sólo en pocos casos están cubiertas por un delgado intervalo de limolitas con ripples de corriente.La laminación cruzada tiene un buzamiento de 5 a 30° y está uniformemente inclinada, al igual que los flute-casts, en la misma dirección que la corriente. Estos últimos se encuentran en el yacente de las mencionadas capas o en la base de las turbiditas asociadas.Estas caracterÃsticas representan formas geométricas de dunas o barras originadas por un régimen de corriente menos intenso
Obesidad, diagnóstico etiológico
I. CONCEPTO Y DEFINICION La obesidad es un problema frecuente en pediatrÃa, con una prevalencia superior al 5 % en la mayoria de series españolas y extranjeras. En muchas ocasiones no constituye de por sà el motivo de consulta al pediatra, detectándose en visitas de control o en consultas por otra patologÃa...
Depositional models of lacustrine evaporites in the SE margin of the Ebro Basin (Paleogene, NE Spain)
An important evaporitic sedimentation occurred during the Paleogene (Eocene to lower Oligocene) in the Barberà sector of the southeastern margin of the Tertiary Ebro Basin. This sedimentation took place in shallow lacustrine environments and was controlled by a number of factors: 1) the tectonic structuration of the margin; 2) the high calcium sulphate content in the meteoric waters coming from the marginal reliefs; 3) the semiarid climate; and 4) the development of large alluvial fans along the basin margin, which also conditioned the location of the saline lakes. The evaporites are currently composed of secondary gypsum in surface and anhydrite at depth. There are, however, vestiges of the local presence of sodium sulphates. The evaporite units, with individual thicknesses ranging between 50 and 100 m, are intercalated within various lithostratigraphic formations and exhibit a paleogeographical pattern. The units located closer to the basin margin are characterized by a massive gypsum lithofacies (originally, bioturbated gypsum) bearing chert, and also by meganodular gypsum locally (originally, meganodules of anhydrite) in association with red lutites and clastic intercalations (gypsarenites, sandstones and conglomerates). Chert, which is only linked to the thickest gypsum layers, seems to be an early diagenetic, lacustrine product. Cyclicity in these proximal units indicates the progressive development of low-salinity, lacustrine bodies on red mud flats. At the top of some cycles, exposure episodes commonly resulted in dissolution, erosion, and the formation of edaphic features. In contrast, the units located in a more distal position with regard to the basin margin are formed by an alternation of banded-nodular gypsum and laminated gypsum layers in association with grey lutites and few clastic intercalations. These distal units formed in saline lakes with a higher ionic concentration. Exposure episodes in these lakes resulted in the formation of synsedimentary anhydrite and sabkha cycles. In some of these units, however, outer rims characterized by a lithofacies association similar to that of the proximal units occur (nodular gypsum, massive gypsum and chert nodules)
Metastatic non-small-cell lung cancer: consensus on pathology and molecular tests, first-line, second-line, and third-line therapy: 1st ESMO Consensus Conference in Lung Cancer; Lugano 2010
The 1st ESMO Consensus Conference on lung cancer was held in Lugano, Switzerland on 21 and 22 May 2010 with the participation of a multidisciplinary panel of leading professionals in pathology and molecular diagnostics, medical oncology, surgical oncology and radiation oncology. Before the conference, the expert panel prepared clinically relevant questions concerning five areas: early and locally advanced non-small-cell lung cancer (NSCLC), first-line metastatic NSCLC, second-/third-line NSCLC, NSCLC pathology and molecular testing, and small-cell lung cancer to be addressed through discussion at the Consensus Conference. All relevant scientific literature for each question was reviewed in advance. During the Consensus Conference, the panel developed recommendations for each specific question. The consensus agreement on three of these areas: NSCLC pathology and molecular testing, the treatment of first-line, and second-line/third-line therapy in metastatic NSCLC are reported in this article. The recommendations detailed here are based on an expert consensus after careful review of published data. All participants have approved this final updat
Use of stable isotope probing to assess the fate of emerging contaminants degraded by white-rot fungus
The widespread of emerging contaminants in the environment and their potential impact on humans is a matter of concern. White-rot fungi are cosmopolitan organisms able to remove a wide range of pharmaceuticals and personal care products (PPCP) through cometabolism (i.e. laccases and peroxidases) or detoxification mechanisms (i.e. cytochrome P450 system). However, the use of PPCP as carbon source for these organisms is largely unexplored. Here, we used carbon stable isotope tracer experiments to assess the fate of anti-inflammatory diclofenac (DCF) and UV filter benzophenone-3 (BP3) during degradation by Trametes versicolor. The comparison between carbon isotopic composition of emitted carbon dioxide from 13C-labelled DCF ([acetophenyl ring-13C6]-DCF) and 13C-BP3 ([phenyl-13C6]-BP3) versus their 12C-homologue compounds showed mineralization of about 45% and 10% of the 13C contained in their respective molecules after 9 days of incubation. The carbon isotopic composition of the bulk biomass and the application of amino acid-stable isotope probing (SIP) allowed distinguishing between incorporation of 13C from BP3 into amino acids, which implies the use of this emerging contaminant as carbon source, and major intracellular accumulation of 13C from DCF without implying the transformation of its labelled phenyl ring into anabolic products. A mass balance of 13C in different compartments over time provided a comprehensive picture of the fate of DCF and BP3 across their different transformation processes. This is the first report assessing biodegradation of PPCP by SIP techniques and the use of emerging contaminants as carbon source for amino acid biosynthesis
Constant theoretical conductance, changes in vessel diameter and number, with height growth in Moringaoleifera
As trees grow taller, hydraulic resistance can be expected to increase, causing photosynthetic productivity to decline. Yet leaves maintain productivity over vast height increases; this maintenance of productivity suggests that leaf-specific conductance remains constant as trees grow taller. Here we test the assumption of constant leaf-specific conductance with height growth and document the anatomical adjustments involved. We measured the scaling of total leaf area, mean vessel diameter at terminal twigs and at the stem base, and total vessel number in 139 individuals of Moringaoleifera of different heights, and estimated a whole-plant conductance index from these measurements. Whole-plant conductance and total leaf area scaled at the same rate with height. Congruently, whole-plant conductance and total leaf area scaled isometrically. Constant conductance is made possible by a complex adjustment in anatomy, with conduit diameters in terminal twigs becoming wider, lowering per-vessel resistance, with a concomitant decrease in vessel number per unit leaf area with height growth. Selection maintaining constant conductance per unit leaf area with height growth (or at least minimizing drops in conductance) is likely a potent selective pressure shaping plant hydraulics, and is crucially involved in the maintenance of photosynthetic productivity per leaf area across the terrestrial landscape
Evaluation of ethyl tert-butyl ether biodegradation in a contaminated aquifer by compound specific isotope analysis and in situ microcosms
Ethyl tert-butyl ether (ETBE) is an upcoming groundwater pollutant in Europe whose environmental fate has been less investigated thus far. In the present study, we investigated the in situ biodegradation of ETBE in a fuel-contaminated aquifer using compound-specific stable isotope analysis (CSIA) and in situ microcosms in combination with total lipid fatty acid (TLFA)-stable isotope probing (SIP). In a first field investigation, CSIA revealed no significant carbon isotope fractionation but low hydrogen isotope fractionation of up to +14 ¿ along the prevailing anoxic ETBE plume suggesting biodegradation of ETBE. Ten months later, oxygen injection was conducted to enhance the biodegradation of petroleum hydrocarbons (PH) at the field site. Within the framework of this remediation measure, in situ microcosms loaded with [13C6]-ETBE (BACTRAP®s) were exposed for 119 days in selected groundwater wells to assess the biodegradation of ETBE by TLFA-SIP under the following conditions: (i) ETBE as main contaminant; (ii) ETBE as main contaminant subjected to oxygen injection; (iii) ETBE plus other PH; (iv) ETBE plus other PH subjected to oxygen injection. Under all conditions investigated, significant 13C-incorporation into microbial total lipid fatty acids extracted from the in situ microcosms was found, providing clear evidence of ETBE biodegradation
Food caching behavior of the Eurasian beaver in northern Europe
Food storage (caching, hoarding), which is observed in many species of animals, increases food availability during times of food insecurity. Both species of beaver (Eurasian beaver, Castor fiber, and the North American beaver, C. canadensis) living at northern latitudes where food may be scarce during winter are larder-hoarders, constructing a food cache of branches of woody species during autumn. We studied the food caching behavior of the Eurasian beaver in three northern European countries (Sweden, Norway, Lithuania) to provide additional insight into this important behavior. Thirty-seven of forty-seven (79%) active family groups had food caches by mid-November and 41 of 47 (87%) had caches by December. Water depth of caches ranged from 1 to 2.3 m and depths at caches in Sweden were significantly deeper than in either Norway or Lithuania. Construction of caches began as early as late September (week 39/40) in Sweden and Lithuania and by mid-October (week 42) in Norway. We observed plasticity in timing of cache initiation but the majority of active sites in all areas had food caches by the beginning of November (week 45). Declining air temperature and mean minimum temperatures of 0 degrees C or below were associated with cache initiation. Caches in Lithuania were larger than in Sweden and Norway, which may be associated with colder winter temperatures. We did not find any relationship between family size or length of territory occupancy and cache size at our Norway sites where population demographics were available. Our results are generally consistent with other studies of food caching behavior in both species and suggest general similarities as well as behavioral plasticity in this important evolutionary strategy
A new approach to model oxygen dependent benthic phosphate fluxes in the Baltic Sea
Highlights
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A new description of sediment phosphorus dynamics was implemented in a 3D-model.
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Oxygen consumption affects oxygen penetration in coastal sediments.
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Low oxygen concentrations determine the oxygen penetration in deeper water sediments.
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More than 80% of the phosphorus loads (1980–2008) are retained in the Baltic Sea.
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Phosphorus is released from anoxic sediments and retained in oxic sediments.
Abstract
The new approach to model the oxygen dependent phosphate release by implementing formulations of the oxygen penetration depths (OPD) and mineral bound inorganic phosphorus pools to the Swedish Coastal and Ocean Biogeochemical model (SCOBI) is described. The phosphorus dynamics and the oxygen concentrations in the Baltic proper sediment are studied during the period 1980–2008 using SCOBI coupled to the 3D-Rossby Centre Ocean model. Model data are compared to observations from monitoring stations and experiments.
The impact from oxygen consumption on the determination of the OPD is found to be largest in the coastal zones where also the largest OPD are found. In the deep water the low oxygen concentrations mainly determine the OPD. Highest modelled release rate of phosphate from the sediment is about 59 × 103 t P year− 1 and is found on anoxic sediment at depths between 60–150 m, corresponding to 17% of the Baltic proper total area. The deposition of organic and inorganic phosphorus on sediments with oxic bottom water is larger than the release of phosphorus, about 43 × 103 t P year− 1. For anoxic bottoms the release of total phosphorus during the investigated period is larger than the deposition, about 19 × 103 t P year− 1. In total the net Baltic proper sediment sink is about 23.7 × 103 t P year− 1. The estimated phosphorus sink efficiency of the entire Baltic Sea is on average about 83% during the period
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