Ecological context determines the choice between prey of different salinities

Food choice has profound implications for the relative intakes of water and salts, and thus for an animal’s physiological state. Discrimination behaviors with respect salt intake have been documented in a number of vertebrate species, but few studies have considered the ecological context in which they occur. Here, we report on the results of a 2-choice experiment designed to examine the influence of dietary salt content and freshwater availability in food discrimination behaviors in red knots Calidris canutus (Aves: Scolopacidae) that feed on mud snails Peringia ulvae (Gastropoda: Hydrobiidae) whose body fluids have either relatively low (25‰) or high (42‰) salinity. Birds ate more and spent longer time foraging on low-salinity mud snails when their salt gland sizes—an indicator of excretory capacity—were relatively small and when they were deprived of freshwater. However, as they enlarged salt glands—following a prolonged exposure to salty diet without access to freshwater—and regained access to freshwater, their preference for low-salinity prey disappeared. Such a change of preference illustrates the context dependency of discrimination. As the birds were able to maintain salt–water balance—inferred from plasma sodium concentration—under all conditions, changes in salinity preferences may occur without measurable physiological signs of osmotic stress. Our results highlight the importance of ecological context for understanding foraging responses. We argue that areas with high salinities could act as refuges for euryhaline invertebrates and fish from top vertebrate predators

Dinámicas socioecológicas y ecoturismo comunitario: Un análisis comparativo en el eje fluvial Guayabero-Guaviare

The effects of the ecotourism in the relationships between inhabitants and their environment are complex and multidimensional. To explore these effects, two community ecotourism initiatives in the Guaviare Province were comparatively analyzed. This territory has been historically affected by the armed conflict and today is given priority as a scenery for the peace construction. The analysis herein articulates approaches both from the political ecology and the socio-ecological systems and considers how important it is to understand the power relations emerging in community ecotourism contexts that, in turn, help to measure how this kind of tourism impacts the socio-ecological dynamics and the strategies by the peasant families who try to diversify their economies to made them sustainable. © 2018, Pontificia Universidad Javeriana. All rights reserved

Rate-equation calculations of the current flow through two-site molecular device and DNA-based junction

Here we present the calculations of incoherent current flowing through the two-site molecular device as well as the DNA-based junction within the rate-equation approach. Few interesting phenomena are discussed in detail. Structural asymmetry of two-site molecule results in rectification effect, which can be neutralized by asymmetric voltage drop at the molecule-metal contacts due to coupling asymmetry. The results received for poly(dG)-poly(dC) DNA molecule reveal the coupling- and temperature-independent saturation effect of the current at high voltages, where for short chains we establish the inverse square distance dependence. Besides, we document the shift of the conductance peak in the direction to higher voltages due to the temperature decrease.Comment: 12 pages, 6 figure

Storm evolution characterization for analysing stone armour damage progression

Storm evolution is fundamental for analysing the damage progression of the different failure modes and establishing suitable protocols for maintaining and optimally sizing structures. However, this aspect has hardly been studied and practically the whole of the studies dealing with the subject adopt the Equivalent triangle storm. As against this approach, two new ones are proposed. The first is the Equivalent Triangle Magnitude Storm model (ETMS), whose base, the triangular storm duration, D, is established such that its magnitude (area describing the storm history above the reference threshold level which sets the storm condition),HT, equals the real storm magnitude. The other is the Equivalent Triangle Number of Waves Storm (ETNWS), where the base is referred in terms of the real storm's number of waves,Nz. Three approaches are used for estimating the mean period, Tm, associated to each of the sea states defining the storm evolution, which is necessary to determine the full energy flux withstood by the structure in the course of the extreme event. Two are based on the Jonswap spectrum representativity and the other uses the bivariate Gumbel copula (Hs, Tm), resulting from adjusting the storm peaks. The representativity of the approaches proposed and those defined in specialised literature are analysed by comparing the main armour layer's progressive loss of hydraulic stability caused by real storms and that relating to theoretical ones. An empirical maximum energy flux model is used for this purpose. The agreement between the empirical and theoretical results demonstrates that the representativity of the different approaches depends on the storm characteristics and point towards a need to investigate other geometrical shapes to characterise the storm evolution associated with sea states heavily influenced by swell wave components

Climatic and soil factors explain the two-dimensional spectrum of global plant trait variation

Plant functional traits can predict community assembly and ecosystem functioning and are thus widely used in global models of vegetation dynamics and land–climate feedbacks. Still, we lack a global understanding of how land and climate affect plant traits. A previous global analysis of six traits observed two main axes of variation: (1) size variation at the organ and plant level and (2) leaf economics balancing leaf persistence against plant growth potential. The orthogonality of these two axes suggests they are differently influenced by environmental drivers. We find that these axes persist in a global dataset of 17 traits across more than 20,000 species. We find a dominant joint effect of climate and soil on trait variation. Additional independent climate effects are also observed across most traits, whereas independent soil effects are almost exclusively observed for economics traits. Variation in size traits correlates well with a latitudinal gradient related to water or energy limitation. In contrast, variation in economics traits is better explained by interactions of climate with soil fertility. These findings have the potential to improve our understanding of biodiversity patterns and our predictions of climate change impacts on biogeochemical cycles

Consenso colombiano de atención, diagnóstico y manejo de la infección por SARS-COV-2/COVID-19 en establecimientos de atención de la salud Recomendaciones basadas en consenso de expertos e informadas en la evidencia

The “Asociación Colombiana de Infectología” (ACIN) and the “Instituto de Evaluación de Nuevas Tecnologías de la Salud” (IETS) created a task force to develop recommendations for Covid 19 health care diagnosis, management and treatment informed, and based, on evidence. Theses reccomendations are addressed to the health personnel on the Colombian context of health services. © 2020 Asociacion Colombiana de Infectologia. All rights reserved

Emerging themes to support ambitious UK marine biodiversity conservation

Healthy marine ecosystems provide a wide range of resources and services that support life on Earth and contribute to human wellbeing. Marine Protected Areas (MPAs) are accepted as an important tool for the restoration and maintenance of marine ecosystem structure, function, health and ecosystem integrity through the conservation of significant species, habitats, or entire ecosystems. In recent years there has been a rapid expansion in the area of ocean designated as an MPA. Despite this progress in spatial protection targets and the progressive knowledge of the essential interdependence between the human and the ocean system, marine biodiversity continues to decline, placing in jeopardy the range of ecosystem services benefits humans rely on. There is a need to address this shortcoming. Ambitious marine conservation:• Requires a shift from managing individual marine features within MPAs to whole-sites to enable repair and renewal of marine systems;• Reflects an ambition for sustainable livelihoods by fully integrating fisheries management with conservation (Ecosystem Based Fisheries Management) as the two are critically interdependent;• Establishes a world class and cost effective ecological and socio-economic monitoring and evaluation framework that includes the use of controls and sentinel sites to improve sustainability in marine management; and• Challenges policy makers and practitioners to be progressive by integrating MPAs into the wider seascape as critical functional components rather than a competing interest and move beyond MPAs as the only tool to underpin the benefits derived from marine ecosystems by identifying other effective area-based conservation measures (OECMs) to establish synergies with wider governance frameworks

Fungal Planet description sheets: 1383–1435

Novel species of fungi described in this study include those from various countries as follows: Australia, Agaricus albofoetidus, Agaricus aureoelephanti and Agaricus parviumbrus on soil, Fusarium ramsdenii from stem cankers of Araucaria cunninghamii, Keissleriella sporoboli from stem of Sporobolus natalensis, Leptosphaerulina queenslandica and Pestalotiopsis chiaroscuro from leaves of Sporobolus natalensis, Serendipita petricolae as endophyte from roots of Eriochilus petricola, Stagonospora tauntonensis from stem of Sporobolus natalensis, Teratosphaeria carnegiei from leaves of Eucalyptus grandis × E. camaldulensis and Wongia ficherai from roots of Eragrostis curvula. Canada, Lulworthia fundyensis from intertidal wood and Newbrunswickomyces abietophilus (incl. Newbrunswickomyces gen. nov.)on buds of Abies balsamea. Czech Republic, Geosmithia funiculosa from a bark beetle gallery on Ulmus minor and Neoherpotrichiella juglandicola (incl. Neoherpotrichiella gen. nov.)from wood of Juglans regia. France, Aspergillus rouenensis and Neoacrodontium gallica (incl. Neoacrodontium gen. nov.)from bore dust of Xestobium rufovillosum feeding on Quercus wood, Endoradiciella communis (incl. Endoradiciella gen. nov.)endophyticin roots of Microthlaspi perfoliatum and Entoloma simulans on soil. India, Amanita konajensis on soil and Keithomyces indicus from soil. Israel, Microascus rothbergiorum from Stylophora pistillata. Italy, Calonarius ligusticus on soil. Netherlands , Appendopyricularia juncicola (incl. Appendopyricularia gen. nov.), Eriospora juncicola and Tetraploa juncicola on dead culms of Juncus effusus, Gonatophragmium physciae on Physcia caesia and Paracosmospora physciae (incl. Paracosmospora gen. nov.)on Physcia tenella, Myrmecridium phragmitigenum on dead culm of Phragmites australis, Neochalara lolae on stems of Pteridium aquilinum, Niesslia nieuwwulvenica on dead culm of undetermined Poaceae, Nothodevriesia narthecii (incl. Nothodevriesia gen. nov.) on dead leaves of Narthecium ossifragum and Parastenospora pini (incl. Parastenospora gen. nov.)on dead twigs of Pinus sylvestris. Norway, Verticillium bjoernoeyanum from sand grains attached to a piece of driftwood on a sandy beach. Portugal, Collybiopsis cimrmanii on the base of living Quercus ilex and amongst dead leaves of Laurus and herbs. South Africa , Paraproliferophorum hyphaenes (incl. Paraproliferophorum gen. nov.) on living leaves of Hyphaene sp. and Saccothecium widdringtoniae on twigs of Widdringtonia wallichii. Spain, Cortinarius dryosalor on soil, Cyphellophora endoradicis endophytic in roots of Microthlaspi perfoliatum, Geoglossum laurisilvae on soil, Leptographium gemmatum from fluvial sediments, Physalacria auricularioides from a dead twig of Castanea sativa , Terfezia bertae and Tuber davidlopezii in soil. Sweden, Alpova larskersii, Inocybe alpestris and Inocybe boreogodeyi on soil. Thailand, Russula banwatchanensis, Russula purpureoviridis and Russula lilacina on soil. Ukraine, Nectriella adonidis on over wintered stems of Adonis vernalis. USA, Microcyclus jacquiniae from living leaves of Jacquinia keyensis and Penicillium neoherquei from a minute mushroom sporocarp. Morphological and culture characteristics are supported by DNA barcodes