10 research outputs found

    Closed-Form transformation between geodetic and ellipsoidal coordinates

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    We present formulas for direct closed-form transformation between geodetic coordinates(Φ, λ, h) and ellipsoidal coordinates (β, λ, u) for any oblate ellipsoid of revolution.These will be useful for those dealing with ellipsoidal representations of the Earth's gravityfield or other oblate ellipsoidal figures. The numerical stability of the transformations for nearpolarand near-equatorial regions is also considered

    Progress and Challenges in Coupled Hydrodynamic-Ecological Estuarine Modeling

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    Insights into the high-energy γ-ray emission of Markarian 501 from extensive multifrequency observations in the Fermi era

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    We report on the γ-ray activity of the blazar Mrk 501 during the first 480 days of Fermi operation. We find that the average Large Area Telescope (LAT) γ-ray spectrum of Mrk 501 can be well described by a single power-law function with a photon index of 1.78 ± 0.03. While we observe relatively mild flux variations with the Fermi-LAT (within less than a factor of two), we detect remarkable spectral variability where the hardest observed spectral index within the LAT energy range is 1.52 ± 0.14, and the softest one is 2.51 ± 0.20. These unexpected spectral changes do not correlate with the measured flux variations above 0.3 GeV. In this paper, we also present the first results from the 4.5 month long multifrequency campaign (2009 March 15-August 1) on Mrk 501, which included the Very Long Baseline Array (VLBA), Swift, RXTE, MAGIC, and VERITAS, the F-GAMMA, GASP-WEBT, and other collaborations and instruments which provided excellent temporal and energy coverage of the source throughout the entire campaign. The extensive radio to TeV data set from this campaign provides us with the most detailed spectral energy distribution yet collected for this source during its relatively low activity. The average spectral energy distribution of Mrk 501 is well described by the standard one-zone synchrotron self-Compton (SSC) model. In the framework of this model, we find that the dominant emission region is characterized by a size ≲0.1 pc (comparable within a factor of few to the size of the partially resolved VLBA core at 15-43 GHz), and that the total jet power (≃1044 erg s-1) constitutes only a small fraction (∼10-3) of the Eddington luminosity. The energy distribution of the freshly accelerated radiating electrons required to fit the time-averaged data has a broken power-law form in the energy range 0.3 GeV-10 TeV, with spectral indices 2.2 and 2.7 below and above the break energy of 20 GeV. We argue that such a form is consistent with a scenario in which the bulk of the energy dissipation within the dominant emission zone of Mrk 501 is due to relativistic, proton-mediated shocks. We find that the ultrarelativistic electrons and mildly relativistic protons within the blazar zone, if comparable in number, are in approximate energy equipartition, with their energy dominating the jet magnetic field energy by about two orders of magnitude. © 2011. The American Astronomical Society

    Aceleração da recuperação após protocolo cirúrgico versus cuidados perioperatórios convencionais em cirurgia colorretal. Um estudo de coorte em centro único [Enhanced recovery after surgery protocol versus conventional perioperative care in colorectal surgery. A single center cohort study]

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    Justificativa: O protocolo ERAS – do Inglês Enhanced Recovery After Surgery – consiste em um conjunto de medidas perioperatórias destinadas a melhorar a recuperação do paciente e diminuir o tempo de internação e as complicações pós-operatórias. Avaliamos a implantação e os resultados de um protocolo ERAS para cirurgia colorretal. Métodos: Estudo observacional em centro único. Os dados foram coletados de pacientes consecutivos submetidos à cirurgia colorretal aberta ou laparoscópica durante dois períodos: três anos antes (pré-ERAS) e dois anos após (pós-ERAS) a implantação de um protocolo ERAS. As características basais de ambos os grupos foram comparadas. O desfecho primário foi o número de pacientes com 180 dias de acompanhamento com complicações moderadas ou graves. Os desfechos secundários foram tempo de internação pós-cirurgia e complicações específicas. Os dados foram extraídos de prontuários dos pacientes. Resultados: O grupo pré-ERAS foi composto por 360 pacientes e o grupo pós-ERAS por 319. No grupo pré ERAS, 214 pacientes (59, 8%) desenvolveram pelo menos uma complicação versus 163 (51, 10%) no grupo pós-ERAS. Um número maior de pacientes do grupo pré-ERAS desenvolveu complicações moderadas ou graves (31, 9% vs. 22, 26%, p = 0, 009); e complicações graves (15, 5% vs. 5, 3%; p < 0, 0001). A mediana do tempo de internação foi de 13 (17) dias no grupo pré-ERAS e de 11 (10) dias no grupo pós-ERAS (p = 0, 034). Não houve diferença nas taxas de mortalidade (4, 7% vs. 2, 5%; p = 0, 1554) ou de reinternação (6, 39% vs. 4, 39%; p = 0, 31). A conformidade geral do protocolo ERAS na coorte pós-ERAS foi de 88%. Conclusões: A implantação do protocolo ERAS para cirurgia colorretal foi associada a uma redução significativa das complicações pós-operatórias e do tempo de internação. Background: Enhanced recovery after surgery (ERAS) protocols consist of a set of perioperative measures aimed at improving patient recovery and decreasing length of stay and postoperative complications. We assess the implementation and outcomes of an ERAS program for colorectal surgery. Methods: Single center observational study. Data were collected from consecutive patients undergoing open or laparoscopic colorectal surgery during 2 time periods, 3 years before (Pre-ERAS) and 2 years after (Post-ERAS) the implementation of an ERAS protocol. Baseline characteristics of both groups were compared. The primary outcome was the number of patients with 180 days follow-up with moderate or severe complications; secondary outcomes were postoperative length of stay, and specific complications. Data were extracted from patient records. Results: There were 360 patients in the Pre-ERAS group and 319 patients in the Post-ERAS Group. 214 (59.8%) patients developed at least one complication in the pre ERAS group, versus 163 patients in the Post-ERAS group (51.10%). More patients in the Pre-ERAS group developed moderate or severe complications (31.9% vs. 22.26%, p = 0.009); and severe complications (15.5% vs. 5.3%; p < 0.0001). The median length of stay was 13 (17) days in Pre-ERAS Group and 11 (10) days in the Post-ERAS Group (p = 0.034). No differences were found on mortality rates (4.7% vs. 2.5%; p = 0.154), or readmission (6.39% vs. 4.39%; p = 0.31). Overall ERAS protocol compliance in the Post-ERAS cohort was 88%. Conclusions: The implementation of ERAS protocol for colorectal surgery was associated with a significantly reduction of postoperative complications and length of stay

    The Global Soil Mycobiome consortium dataset for boosting fungal diversity research.

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    Fungi are highly important biotic components of terrestrial ecosystems, but we still have a very limited understanding about their diversity and distribution. This data article releases a global soil fungal dataset of the Global Soil Mycobiome consortium (GSMc) to boost further research in fungal diversity, biogeography and macroecology. The dataset comprises 722,682 fungal operational taxonomic units (OTUs) derived from PacBio sequencing of full-length ITS and 18S-V9 variable regions from 3200 plots in 108 countries on all continents. The plots are supplied with geographical and edaphic metadata. The OTUs are taxonomically and functionally assigned to guilds and other functional groups. The entire dataset has been corrected by excluding chimeras, index-switch artefacts and potential contamination. The dataset is more inclusive in terms of geographical breadth and phylogenetic diversity of fungi than previously published data. The GSMc dataset is available over the PlutoF repository

    Global patterns in endemicity and vulnerability of soil fungi.

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    Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms

    Oscillations

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