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Context/Purpose: The stress-dominance hypothesis (SDH) is a model of community assembly predicting that the relative importance of environmental filtering increases and competition decreases along a gradient of increasing environmental stress. Therefore, trait variation at the community level should increase as resources are more available. Although the SDH was designed to explain spatial changes in plant communities based on aboveground traits, it is possible that root communities show similar switches in strategies at temporal scales in response to pulses in resource availability. Methods: To test this hypothesis we sampled for two years the morphological changes in root systems in a mature tropical forest in Central Amazon. Thirty-six samples along a 500 m transect were taken each three months from February 2016 to February 2018, separating the uppermost organic layer (0-5 cm) from the mineral soil (5-15 cm). Besides root biomass, we scanned approximately 20% of the total root systems to calculate specific root length (SRL), average diameter (D), root tissue density (RTD), and branching index (BI). Spatially, we expected shifts from acquisitive to conservative syndromes as roots penetrate in the mineral soil. Temporarily, we hypothesized that traits associated with resource acquisition (SRL, SRTA, BI) will increase with soil moisture. Moreover, we expected that trait range will increase as resources become more available. Results: We found significant differences in biomass and morphological traits between the organic and mineral soils. We found no patterns between biomass increases in seasonality, but mean community traits change significantly with seasonal rain patterns. More interestingly, changes in mean and range values were more strongly associated with rain events three months before the collecting date, suggesting a lagging between rain events and belowground community responses. Conclusions: Belowground dynamics are structured spatially and temporarily in tropical forests, in synchrony with the availability of resources, as predicted by the SHD. Our results suggest that species tend to show similar traits during stressful times but diverge during acquisition periods. The results suggest a belowground dimension to niche segregation little explored in tropical biomes to date.

Injuries for animal bites are a common cause of consultation to emergency services. However there are still controversies about some aspects of their treatment. It is not recommended to brush the wound area but to flush the surface with isoosmolar saline. The primary wound closure is justified when improves the cosmetic outcome and has no increase risk of infection. Antibiotic prophylaxis is allways indicated in cats or humans bites. The drug of choice is amoxicillin clavulanate.The tetanus vaccine should be indicated when the patient has not full vaccination scheme and rabies vaccine in cases of suspected or confirmed infected animals.

During the last deglaciation, the Bolivian Altiplano (15-23 degrees S, 66-70 degrees W) was occupied by paleolake Tauca covering, at least, similar to 51,000 km(2) at its maximum highstand between 16.5 and 15 ka. Twenty-five hundred years later, after a massive regression, a new transgressive phase, produced paleolake Coipasa, smaller than Tauca and restricted to the southern part of the basin. These paleolakes were overlooked at the west by the Sajama ice cap. The latter provides a continuous record of the oxygen isotopic composition of paleo-precipitation for the last 25 ka. Contemporaneously to the end of paleolake Tauca, around 14.3 ka, the Sajama ice cap recorded a significant increase in ice oxygen isotopic composition (delta O-18(ice)). This paper examines to what extent the disappearance of Lake Tauca contributed to precipitation on the Sajama summit and this specific isotopic variation. The water delta O-18 values of paleolakes Tauca and Coipasa (delta O-18(lake)) were quantitatively reconstructed from 18.5 to 11.7 ka based on diatom isotopic composition (delta O-18(diatoms)) and ostracod isotopic composition (delta O-18(carbonates)) retrieved in lacustrine sediments. At a centennial time scale, a strong trend appears: abrupt decreases of delta O-18(lake) during lake fillings are immediately followed by abrupt increases of delta O-18(lake) during lake level stable phases. The highest variation occurred at similar to 15.8 ka with a delta O-18(lake) decrease of about similar to 10%o, concomitant with the Lake Tauca highstand, followed similar to 400 years later by a 7 parts per thousand increase in delta O-18(lake). A simple hydro-isotopic modeling approach reproduces consistently this rapid "decrease-increase" feature. Moreover, it suggests that this unexpected re-increase in delta O-18(lake) after filling phases can be partly explained by an equilibration of isotopic fluxes during the lake steady-state. Based on isotopic calculations during lake evaporation and a simple water stable isotopes balance between potential moisture sources at Sajama (advection versus lake evaporation), we show that total or partial evaporation (from 5 to 60%) of paleolake Tauca during its major regression phase at 14.3 ka could explain the pronounced isotopic excursion at Sajama ice cap. These results suggest that perturbations of the local hydrological cycle in lacustrine areas may substantially affect the paleoclimatic interpretation of the near-by isotopic signals (e.g. ice core or speleothems).

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Introduccion. La legislacion espanola vigente establece los criterios de muerte encefalica (ME) y las pruebas complementarias de confirmacion ?que no siempre es necesario realizar?. Entre ellas, la mas utilizada en nuestro pais es el electroencefalograma (EEG), que tiene limitaciones en pacientes con sedacion barbiturica. El Doppler transcraneal (DTC) presenta numerosas ventajas para el diagnostico de ME, pero tambien algunas limitaciones. En esos casos, la gammagrafia de perfusion cerebral (GPC) con HMPAO puede ser de gran utilidad. Casos clinicos. Se presentan dos pacientes jovenes que ingresan en la Unidad de Cuidados Intensivos tras traumatismo craneoencefalico grave. Evolucionan desfavorablemente y presentan exploracion clinica compatible con ME. Los EEG, al tratarse ambos pacientes con barbituricos, son de interpretacion compleja. El DTC es dificil de realizar en ambos casos, por presentar perdida de masa encefalica y desplazamiento de estructuras intracraneales, respectivamente. La GPC, sin embargo, permitio confirmar el diagnostico de ME. Conclusion. El DTC, aunque presenta evidentes ventajas, no siempre puede realizarse para confirmar el diagnostico de ME. En esos casos, la GPC puede ser muy util.

The length of time that carbon remains in forest biomass is one of the largest uncertainties in the global carbon cycle, with both recent historical baselines and future responses to environmental change poorly constrained by available observations. In the absence of large-scale observations, models used for global assessments tend to fall back on simplified assumptions of the turnover rates of biomass and soil carbon pools. In this study, the biomass carbon turnover times calculated by an ensemble of contemporary terrestrial biosphere models (TBMs) are analysed to assess their current capability to accurately estimate biomass carbon turnover times in forests and how these times are anticipated to change in the future. Modelled baseline 1985–2014 global average forest biomass turnover times vary from 12.2 to 23.5 years between TBMs. TBM differences in phenological processes, which control allocation to, and turnover rate of, leaves and fine roots, are as important as tree mortality with regard to explaining the variation in total turnover among TBMs. The different governing mechanisms exhibited by each TBM result in a wide range of plausible turnover time projections for the end of the century. Based on these simulations, it is not possible to draw robust conclusions regarding likely future changes in turnover time, and thus biomass change, for different regions. Both spatial and temporal uncertainty in turnover time are strongly linked to model assumptions concerning plant functional type distributions and their controls. Thirteen model-based hypotheses of controls on turnover time are identified, along with recommendations for pragmatic steps to test them using existing and novel observations. Efforts to resolve uncertainty in turnover time, and thus its impacts on the future evolution of biomass carbon stocks across the world's forests, will need to address both mortality and establishment components of forest demography, as well as allocation of carbon to woody versus non-woody biomass growth.

Muñoz-Écija, Teresa; Vargas-Quesada, Benjamín; Chinchilla-Rodríguez, Zaida; Gómez-Núñez, Antonio Jesús; Moya-Anegón, Félix. Nanoscience and Nanotechnology in Scopus: Journal Identification and Visualization. 14th International Society of Scientometrics and Informetrics Conference, Vienna (Austria), 15th-19th July 2013, This document presents a new query for the retrieval of information about Nanoscience & Nanotechnology (N&N) based on the combination of previously published search strategies, contrasted by the scientific community. It led us to identify 80 core journals of N&N in Scopus, then map and analyze the underlying structure of N&N output using visualization techniques. N&N is established as a productive young discipline, crosscutting other fields in its rapid evolution, for which reason it has poorly defined limits to date, and needs some time to consolidate its identity as a discipline. Materials & Methods On 06/11/2012 we launched a search against the Scopus database using the combination of different queries proposed previously. Query 1 included terms with the root nano*, while excluding any terms containing the root nano* yet not related with N&N. To this end, we referred to the combination of proposals made by Noyons et al., 2003; Glänzel et al., 2003; Huang et al., 2003; and Meyer, Debackere and Glänzel, 2010. In turn, query 2 combined instruments and processes utilized in N&N with different types of materials, functions and other terms, in the wake of proposals by Noyons et al., 2003, Glänzel et al., 2003, Kostoff, Koytcheff and Lau, 2007 and Porter et al., 2008. Finally, query 3 included a series of terms related with N&N and was based on the work of Noyons et al., 2003; Glänzel et al., 2003; Huang et al., 2003; Kostoff, Koytcheff and Lau, 2006; Porter et al., 2008; and Lv et al., 2011. The combination of these three searches led to a new query which we believe can be perfectly adopted for the identification of N&N documents in any specialized or multidisciplinary database (Annex).