40 research outputs found

    Análise Espacial Da Produtividade De Serapilheira Em Uma Mata De Galeria

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    The gallery forests have great genetic diversity and important ecological functions, such as protecting the headwaters, controlling erosion, and functioning as buffer zones and filtering chemicals. Litterfall, which can be used as an indicator of ecological productivity, is widely collected using litter traps that are randomly distributed in a forest plot. However, vegetation distribution may present spatial dependence, thus the yield of the litterfall can be mapped using geostatistical techniques allowing the delineation of management zones. Therefore, the objective of this study was to evaluate the efficiency of geostatistical methods using the zoning management productivity of litterfall on a gallery forest in central Brazil. The study was conducted on the gallery forest along the ‘Lava-pés’ stream in Goiás State, Brazil where the experimental site (3 ha) was structured in a grid of 60 litterfall traps, each of 0.33 m2 held 0.65 m above the ground, georeferenced, spaced at 32 x 32 m intervals. Litterfall was monthly collected from December 2011 to November 2012. All litterfall samples were manually separated into three fractions: leaves (LE), branch bark (BB), and reproductive parts (RP) and they were expressed in kg ha-1. Statistical analyses consisted of data description and geostatistics. The litterfall of for LE and total showed strong spatial dependence. The BB and RP showed pure nugget effect. The total litterfall maps obtained by the Kriging interpolation method indicated zones in the map ranging from 900 to 10,900 kg ha-1 per yr. The kriging interpolation technique delineate management zones of productivity in the gallery forest litterfall studied, which allowed the specific forest management of litterfall. © 2016, Universidade Federal de Santa Maria. All Rights Reserved.26248950

    Identification of orthologous regions associated with tissue growth under water-limited conditions

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    Plant recovery from early season drought is related to the amount of biomass retained during stress and biomass production after the end of stress. Reduction in leaf expansion is one of the first responses to water deficit. It is assumed that the control of tissue development under water deficit contributes to traits such as early vigor, as well as maintenance of growth of reproductive organs. To dissect the underlying mechanisms controlling tissue expansion under water-limited conditions, we used a multilevel approach combining quantitative genetics and genomics. To identify orthologous genetic regions controlling tissue growth under water-limited conditions a series of QTL mapping and microarray gene expression studies were conducted in rice and maize. Results of differentially expressed genes from microarray experiments, QTLs and candidate genes related to growth in the different species are compared on consensus maps (within species) and then on synteny maps (between species), to identify common genetic regions between rice and maize

    Desafios políticos para a consolidação do Sistema Único de Saúde: uma abordagem histórica

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    Collider aspects of flavour physics at high Q

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    This review presents flavour related issues in the production and decays of heavy states at LHC, both from the experimental side and from the theoretical side. We review top quark physics and discuss flavour aspects of several extensions of the Standard Model, such as supersymmetry, little Higgs model or models with extra dimensions. This includes discovery aspects as well as measurement of several properties of these heavy states. We also present public available computational tools related to this topic.Comment: Report of Working Group 1 of the CERN Workshop ``Flavour in the era of the LHC'', Geneva, Switzerland, November 2005 -- March 200

    Mapping geographical inequalities in access to drinking water and sanitation facilities in low-income and middle-income countries, 2000-17

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    Background: Universal access to safe drinking water and sanitation facilities is an essential human right, recognised in the Sustainable Development Goals as crucial for preventing disease and improving human wellbeing. Comprehensive, high-resolution estimates are important to inform progress towards achieving this goal. We aimed to produce high-resolution geospatial estimates of access to drinking water and sanitation facilities. Methods: We used a Bayesian geostatistical model and data from 600 sources across more than 88 low-income and middle-income countries (LMICs) to estimate access to drinking water and sanitation facilities on continuous continent-wide surfaces from 2000 to 2017, and aggregated results to policy-relevant administrative units. We estimated mutually exclusive and collectively exhaustive subcategories of facilities for drinking water (piped water on or off premises, other improved facilities, unimproved, and surface water) and sanitation facilities (septic or sewer sanitation, other improved, unimproved, and open defecation) with use of ordinal regression. We also estimated the number of diarrhoeal deaths in children younger than 5 years attributed to unsafe facilities and estimated deaths that were averted by increased access to safe facilities in 2017, and analysed geographical inequality in access within LMICs. Findings: Across LMICs, access to both piped water and improved water overall increased between 2000 and 2017, with progress varying spatially. For piped water, the safest water facility type, access increased from 40·0% (95% uncertainty interval [UI] 39·4–40·7) to 50·3% (50·0–50·5), but was lowest in sub-Saharan Africa, where access to piped water was mostly concentrated in urban centres. Access to both sewer or septic sanitation and improved sanitation overall also increased across all LMICs during the study period. For sewer or septic sanitation, access was 46·3% (95% UI 46·1–46·5) in 2017, compared with 28·7% (28·5–29·0) in 2000. Although some units improved access to the safest drinking water or sanitation facilities since 2000, a large absolute number of people continued to not have access in several units with high access to such facilities (>80%) in 2017. More than 253 000 people did not have access to sewer or septic sanitation facilities in the city of Harare, Zimbabwe, despite 88·6% (95% UI 87·2–89·7) access overall. Many units were able to transition from the least safe facilities in 2000 to safe facilities by 2017; for units in which populations primarily practised open defecation in 2000, 686 (95% UI 664–711) of the 1830 (1797–1863) units transitioned to the use of improved sanitation. Geographical disparities in access to improved water across units decreased in 76·1% (95% UI 71·6–80·7) of countries from 2000 to 2017, and in 53·9% (50·6–59·6) of countries for access to improved sanitation, but remained evident subnationally in most countries in 2017. Interpretation: Our estimates, combined with geospatial trends in diarrhoeal burden, identify where efforts to increase access to safe drinking water and sanitation facilities are most needed. By highlighting areas with successful approaches or in need of targeted interventions, our estimates can enable precision public health to effectively progress towards universal access to safe water and sanitation

    Whole-genome sequencing reveals host factors underlying critical COVID-19

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    Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

    Método para la determinación de la densidad de una muestra de granos enteros de alubia por procesamiento digital de imágenes

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    En este trabajo se presenta una metodología alternativa para la determinación de la densidad de una muestra de granos enteros de alubia (Phaselous vulgaris L) basada en procesamiento digital de imágenes, caracterizada por su sencillez y fácil implementación. Requiere de las medidas de la masa y del volumen de la muestra, las que son realizadas con una balanza y con un modelo tridimensional del grano respectivamente. En este modelo tridimensional se asume que el volumen de cada grano es proporcional a su largo y al cuadrado de su ancho. Estos dos últimos valores son determinados a partir del empleo de técnicas de procesamiento digital de imágenes aplicadas a la imagen de muestras de granos enteros obtenidas con un escáner de escritorio. La constante de proporcionalidad se determina experimentalmente por comparación con el volumen de la muestra obtenido posteriormente por el método de desplazamiento de tolueno. Se prepararon diez muestras para determinar y analizar el comportamiento de la constante de proporcionalidad y cinco para validación del modelo propuesto. La densidad obtenida con esta metodología para las muestras de validación se contrastó con la obtenida con el método de desplazamiento de tolueno siendo la diferencia relativa porcentual inferior al 5%

    Weakly driven anomalous diffusion in non-ergodic regime: an analytical solution

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    We derive the probability density of a diffusion process generated by nonergodic velocity fluctuations in presence of a weak potential, using the Liouville equation approach. The velocity of the diffusing particle undergoes dichotomic fluctuations with a given distribution ψ(τ)\psi(\tau) of residence times in each velocity state. We obtain analytical solutions for the diffusion process in a generic external potential and for a generic statistics of residence times, including the non-ergodic regime in which the mean residence time diverges. We show that these analytical solutions are in agreement with numerical simulations.Comment: 7 pages, 4 figure
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