712 research outputs found
Guandu: planta forrageira para a produção de proteína.
O guandu (Cajanus cajan), leguminosa de origem africana, adaptada a região Tropical, é enfocada no documento apenas quanto a seu emprego na alimentação de bovinos. São apresentadas recomendações de adubação; época de plantio; cálculo de produção; utilização em pastejo e na produção de forragem. O emprego do guandu, introduzido em pastagens de gramíneas ja existentes, é recomendado para a produção de forragem especial e recuperação de solo.bitstream/item/138535/1/COT-21.pdfCNPG
Antimicrobial resistant Escherichia coli in hospitalised companion animals and their hospital environment
Effect of Fourier filters in removing periodic systematic effects from CMB data
We consider the application of high-pass Fourier filters to remove periodic
systematic fluctuations from full-sky survey CMB datasets. We compare the
filter performance with destriping codes commonly used to remove the effect of
residual 1/f noise from timelines. As a realistic working case, we use
simulations of the typical Planck scanning strategy and Planck Low Frequency
Instrument noise performance, with spurious periodic fluctuations that mimic a
typical thermal disturbance. We show that the application of Fourier high-pass
filters in chunks always requires subsequent normalisation of induced offsets
by means of destriping. For a complex signal containing all the astrophysical
and instrumental components, the result obtained by applying filter and
destriping in series is comparable to the result obtained by destriping only,
which makes the usefulness of Fourier filters questionable for removing this
kind of effects.Comment: 10 pages, 8 figures, published in Astronomy & Astrophysic
Cosmological origin of anomalous radio background
The ARCADE 2 collaboration has reported a significant excess in the isotropic radio background, whose homogeneity cannot be reconciled with clustered sources. This suggests a cosmological origin prior to structure formation. We investigate several potential mechanisms and show that injection of relativistic electrons through late decays of a metastable particle can give rise to the observed excess radio spectrum through synchrotron emission. However, constraints from the cosmic microwave background (CMB) anisotropy, on injection of charged particles and on the primordial magnetic field, present a challenge. The simplest scenario is with a gtrsim9 GeV particle decaying into e+e− at a redshift of z ~ 5, in a magnetic field of ~ 5μG, which exceeds the CMB B-field constraints, unless the field was generated after decoupling. Decays into exotic millicharged particles can alleviate this tension, if they emit synchroton radiation in conjunction with a sufficiently large background magnetic field of a dark U(1)' gauge field
Engineering an endocrine Neo-Pancreas by repopulation of a decellularized rat pancreas with islets of Langerhans
Decellularization of pancreata and repopulation of these non-immunogenic
matrices with islets and endothelial cells could provide transplantable,
endocrine Neo- Pancreata. In this study, rat pancreata were perfusion
decellularized and repopulated with intact islets, comparing three perfusion
routes (Artery, Portal Vein, Pancreatic Duct). Decellularization effectively
removed all cellular components but conserved the pancreas specific
extracellular matrix. Digital subtraction angiography of the matrices showed a
conserved integrity of the decellularized vascular system but a contrast
emersion into the parenchyma via the decellularized pancreatic duct. Islets
infused via the pancreatic duct leaked from the ductular system into the peri-
ductular decellularized space despite their magnitude. TUNEL staining and
Glucose stimulated insulin secretion revealed that islets were viable and
functional after the process. We present the first available protocol for
perfusion decellularization of rat pancreata via three different perfusion
routes. Furthermore, we provide first proof-of-concept for the repopulation of
the decellularized rat pancreata with functional islets of Langerhans. The
presented technique can serve as a bioengineering platform to generate
implantable and functional endocrine Neo-Pancreata
Software defect prediction: do different classifiers find the same defects?
Open Access: This article is distributed under the terms of the Creative Commons Attribution 4.0 International License CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.During the last 10 years, hundreds of different defect prediction models have been published. The performance of the classifiers used in these models is reported to be similar with models rarely performing above the predictive performance ceiling of about 80% recall. We investigate the individual defects that four classifiers predict and analyse the level of prediction uncertainty produced by these classifiers. We perform a sensitivity analysis to compare the performance of Random Forest, Naïve Bayes, RPart and SVM classifiers when predicting defects in NASA, open source and commercial datasets. The defect predictions that each classifier makes is captured in a confusion matrix and the prediction uncertainty of each classifier is compared. Despite similar predictive performance values for these four classifiers, each detects different sets of defects. Some classifiers are more consistent in predicting defects than others. Our results confirm that a unique subset of defects can be detected by specific classifiers. However, while some classifiers are consistent in the predictions they make, other classifiers vary in their predictions. Given our results, we conclude that classifier ensembles with decision-making strategies not based on majority voting are likely to perform best in defect prediction.Peer reviewedFinal Published versio
Wide-Field InfraRed Survey Telescope (WFIRST) Final Report
In December 2010, NASA created a Science Definition Team (SDT) for WFIRST,
the Wide Field Infra-Red Survey Telescope, recommended by the Astro 2010
Decadal Survey as the highest priority for a large space mission. The SDT was
chartered to work with the WFIRST Project Office at GSFC and the Program Office
at JPL to produce a Design Reference Mission (DRM) for WFIRST. Part of the
original charge was to produce an interim design reference mission by mid-2011.
That document was delivered to NASA and widely circulated within the
astronomical community. In late 2011 the Astrophysics Division augmented its
original charge, asking for two design reference missions. The first of these,
DRM1, was to be a finalized version of the interim DRM, reducing overall
mission costs where possible. The second of these, DRM2, was to identify and
eliminate capabilities that overlapped with those of NASA's James Webb Space
Telescope (henceforth JWST), ESA's Euclid mission, and the NSF's ground-based
Large Synoptic Survey Telescope (henceforth LSST), and again to reduce overall
mission cost, while staying faithful to NWNH. This report presents both DRM1
and DRM2.Comment: 102 pages, 57 figures, 17 table
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