36 research outputs found

    Branch xylem density variations across Amazonia

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    International audienceMeasurements of branch xylem density, Dx, were made for 1466 trees representing 503 species, sampled from 80 sites across the Amazon basin. Measured values ranged from 240 kg m?3 for a Brosimum parinarioides from Tapajos in West Pará, Brazil to 1130 kg m?3 for an Aiouea sp. from Caxiuana, Central Pará, Brazil. Analysis of variance showed significant differences in average Dx across the sample plots as well as significant differences between families, genera and species. A partitioning of the total variance in the dataset showed that geographic location and plot accounted for 33% of the variation with species identity accounting for an additional 27%; the remaining "residual" 40% of the variance accounted for by tree to tree (within species) variation. Variations in plot means, were, however, hardly accountable at all by differences in species composition. Rather, it would seem that variations of xylem density at plot level must be explained by the effects of soils and/or climate. This conclusion is supported by the observation that the xylem density of the more widely distributed species varied systematically from plot to plot. Thus, as well as having a genetic component branch xylem density is a plastic trait that, for any given species, varies according to where the tree is growing and in a predictable manner. Exceptions to this general rule may be some pioneers belonging to Pourouma and Miconia and some species within the genera Brosimum, Rinorea and Trichillia which seem to be more constrained in terms of this plasticity than most species sampled as part of this study

    The Mars Environmental Dynamics Analyzer, MEDA. A Suite of Environmental Sensors for the Mars 2020 Mission

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    86 pags., 49 figs., 24 tabs.NASA’s Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.This work has been funded by the Spanish Ministry of Economy and Competitiveness, through the projects No. ESP2014-54256-C4-1-R (also -2-R, -3-R and -4-R) and AYA2015-65041-P; Ministry of Science, Innovation and Universities, projects No. ESP2016-79612-C3-1-R (also -2-R and -3-R), ESP2016-80320-C2-1-R, RTI2018-098728-B-C31 (also -C32 and -C33) and RTI2018-099825-B-C31; Instituto Nacional de Técnica Aeroespacial; Ministry of Science and Innovation’s Centre for the Development of Industrial Technology; Grupos Gobierno Vasco IT1366-19; and European Research Council Consolidator Grant no 818602. The US co-authors performed their work under sponsorship from NASA’s Mars 2020 project, from the Game Changing Development program within the Space Technology Mission Directorate and from the Human Exploration and Operations Directorate

    Ecological approaches in veterinary epidemiology: mapping the risk of bat-borne rabies using vegetation indices and night-time light satellite imagery

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    Rabies remains a disease of significant public health concern. In the Americas, bats are an important source of rabies for pets, livestock, and humans. For effective rabies control and prevention, identifying potential areas for disease occurrence is critical to guide future research, inform public health policies, and design interventions. To anticipate zoonotic infectious diseases distribution at coarse scale, veterinary epidemiology needs to advance via exploring current geographic ecology tools and data using a biological approach. We analyzed bat-borne rabies reports in Chile from 2002 to 2012 to establish associations between rabies occurrence and environmental factors to generate an ecological niche model (ENM). The main rabies reservoir in Chile is the bat species Tadarida brasiliensis; we mapped 726 occurrences of rabies virus variant AgV4 in this bat species and integrated them with contemporary Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS). The correct prediction of areas with rabies in bats and the reliable anticipation of human rabies in our study illustrate the usefulness of ENM for mapping rabies and other zoonotic pathogens. Additionally, we highlight critical issues with selection of environmental variables, methods for model validation, and consideration of sampling bias. Indeed, models with weak or incorrect validation approaches should be interpreted with caution. In conclusion, ecological niche modeling applications for mapping disease risk at coarse geographic scales have a promising future, especially with refinement and enrichment of models with additional information, such as night-time light data, which increased substantially the model’s ability to anticipate human rabies

    RICORS2040 : The need for collaborative research in chronic kidney disease

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    Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true

    The Mars Environmental Dynamics Analyzer, MEDA. A Suite of Environmental Sensors for the Mars 2020 Mission

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    86 pags, 49 figs, 24 tabsNASA's Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.This work has been funded by the Spanish Ministry of Economy and Competitiveness, through the projects No. ESP2014-54256-C4-1-R (also -2-R, -3-R and -4-R) and AYA2015-65041-P; Ministry of Science, Innovation and Universities, projects No. ESP2016-79612-C3-1-R (also -2-R and -3-R), ESP2016-80320-C2-1-R, RTI2018-098728-B-C31 (also -C32 and -C33) and RTI2018-099825-B-C31; Instituto Nacional de Tecnica Aeroespacial; Ministry of Science and Innovation's Centre for the Development of Industrial Technology; Grupos Gobierno Vasco IT1366-19; and European Research Council Consolidator Grant no 818602.Peer reviewe

    An evaluation of algorithms for the remote sensing of cyanobacterial biomass

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    Most remote sensing algorithms for phytoplankton in inland waters aim at the retrieval of the pigment chlorophyll a (Chl a), as this pigment is a useful proxy for phytoplankton biomass. More recently, algorithms have been developed to quantify the pigment phycocyanin (PC), which is characteristic of cyanobacteria, a phytoplankton group of relative importance to inland water management due to their negative impact on water quality in response to eutrophication. We evaluated the accuracy of three published algorithms for the remote sensing of PC in inland waters, using an extensive database of field radiometric and pigment data obtained in the Netherlands and Spain in the period 2001–2005. The three algorithms (a baseline, single band ratio, and a nested band ratio approach) all target the PC absorption effect observed in reflectance spectra in the 620 nm region. We evaluated the sensitivity of the algorithms to errors in reflectance measurements and in All algorithms performed best in moderate to high PC concentrations (50–200 mg m− 3) and showed the most linear response to increasing PC in cyanobacteria-dominated waters. The highest errors showed at PC < 50 mg m− 3. In eutrophic waters, the presence of other pigments explained a tendency to overestimate the PC concentration. In oligotrophic waters, negative PC predictions were observed. At very high concentrations (PC > 200 mg m− 3), PC underestimations by the baseline and single band ratio a

    Obesidad e indicadores antropométricos en una muestra de varones con Síndrome Coronario Agudo, en un Área de Salud que incluye reclusos: estudio caso-control

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    Objetivos: la obesidad es un factor de riesgo cardiovascular con alta prevalencia, y relacionado con la cardiopatia isquemica. El objetivo fue analizar mediante antropometria, una muestra de varones con Síndrome Coronario Agudo (SCA) diagnosticado en un hospital de referencia penitenciaria, y un grupo control. Material y método: estudio caso-control en un Área de Salud que integraba a un Centro Penitenciario. Los participantes fueron 204 varones, 102 infartados y un control por cada caso. Se midió peso, talla, cintura minima (CC), cintura umbilical (CU) y cadera. Se calcularon el IMC y otros indicadores. Se realizo un análisis descriptivo y se obtuvieron las áreas bajo la curva (ABC) "receiver operating characteristich", las odds ratio (OR), y las correlaciones en SCA. Resultados: la obesidad presentó mayor prevalencia en SCA (31,4% vs 9,1%; OR: 4,7), otros indicadores mostraron asociación discriminatoria: IMC (ABC: 0,699; OR: 3,9), CC (ABC: 0,750; OR: 6,3), CU (ABC: 0,777; OR: 10), talla inversa (ABC: 0,619; OR: 2,1), índice cintura/cadera (ABC: 0,832; OR: 11,6); índice CU/cadera (ABC: 0,857; OR: 15,6), índice CU/talla (ABC: 0,800; OR: 8,9). Las correlaciones entre las cinturas y los índices cintura-talla fueron fuertes (todas r >0,90; p <0,001). Discusión: los indicadores antropométricos de obesidad están asociados al SCA. La CU es la medida simple más asociada. El IMC presenta una asociación débil; el índice CU/talla presenta alto poder discriminatorio y la mejor correlación antropométrica de riesgo, apoyando su uso en la identificación de varones con riesgo de infarto de miocardio tanto en la población general como penitenciaria

    Aplicación práctica de los test cognitivos breves

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    Resumen: Introducción: Los test cognitivos breves (TCB) pueden ayudar a detectar el deterioro cognitivo (DC) en el ámbito asistencial. Se han desarrollado y/o validado varios TCB en nuestro país, pero no existen recomendaciones específicas para su uso. Desarrollo: Revisión de estudios sobre el rendimiento diagnóstico en la detección del DC llevados a cabo en España con TCB que requieran menos de 20 min y recomendaciones de uso consensuadas por expertos, sobre la base de las características de los TCB y de los estudios disponibles. Conclusión: El Fototest, el Memory Impairment Screen (MIS) y el Mini-Mental State Examination (MMSE) son las opciones más recomendables para el primer nivel asistencial, pudiendo añadirse otros test (Test del Reloj [TR] y test de fluidez verbal [TFV]) en caso de resultado negativo y queja o sospecha persistente (aproximación escalonada). En el segundo nivel asistencial es conveniente una evaluación sistemática de las distintas áreas cognitivas, que puede llevarse a cabo con instrumentos como el Montreal Cognitive Assessment, el MMSE, el Rowland Universal Dementia Assessment o el Addenbrooke's Cognitive Examination, o bien mediante el uso escalonado o combinado de herramientas más simples (TR, TFV, Fototest, MIS, Test de Alteración de la Memoria y Eurotest). El uso asociado de cuestionarios cumplimentados por un informador (CCI) aporta valor añadido a los TCB en la detección del DC.La elección de los instrumentos vendrá condicionada por las características del paciente, la experiencia del clínico y el tiempo disponible. Los TCB y los CCI deben reforzar —pero nunca suplantar— el juicio clínico, la comunicación con el paciente y el diálogo interprofesional. Abstract: Introduction: Brief cognitive tests (BCT) may help detect cognitive impairment (CI) in the clinical setting. Several BCT have been developed and/or validated in our country, but we lack specific recommendations for use. Development: Review of studies on the diagnostic accuracy of BCT for CI, using studies conducted in Spain with BCT which take less than 20 min. We provide recommendations of use based on expert consensus and established on the basis of BCT characteristics and study results. Conclusion: The Fototest, the Memory Impairment Screen (MIS) and the Mini-Mental State Examination (MMSE) are the preferred options in primary care; other BCT (Clock Drawing Test [CDT], test of verbal fluency [TVF]) may also be administered in cases of negative results with persistent suspected CI or concern (stepwise approach). In the specialised care setting, a systematic assessment of the different cognitive domains should be conducted using the Montreal Cognitive Assessment, the MMSE, the Rowland Universal Dementia Assessment, the Addenbrooke's Cognitive Examination, or by means of a stepwise or combined approach involving more simple tests (CDT, TVF, Fototest, MIS, Memory Alteration Test, Eurotest). Associating an informant questionnaire (IQ) with the BCT is superior to the BCT alone for the detection of CI.The choice of instruments will depend on the patient's characteristics, the clinician's experience, and available time. The BCT and IQ must reinforce — but never substitute — clinical judgment, patient-doctor communication, and inter-professional dialogue. Palabras clave: Test cognitivos breves, Deterioro cognitivo, Detección, Cribado, Atención primaria, Atención especializada, Keywords: Brief cognitive tests, Cognitive impairment, Detection, Screening, Primary care, Specialised car
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