533 research outputs found
Ingestive Behavior of Beef Cattle Fed Either Protein or Energy Supplements under a Rotational Grazing System
Eight Nellore bullocks were assigned to a Tanzânia grass pasture (Panicum maximum Jacq.) under a rotational grazing system, to evaluate the ingestive behavior under two different grazing residues. Stocking rate intensity was used to reach either 1000 kg DM.ha-1 (R1) or 4000 kg DM.ha-1 (R2) as residual targets. Three grazing days followed by 33 days resting period, composed a 36 day grazing cycle. Each grazing plot supported four animals, in a 4x4 Latin square design, within the following supplementation rates and sources: S1 = no supplement; S2 = 2,0 kg DM.day-1 coarsely ground corn - 8 mm sieve; S3 = 2,0 kg DM.day-1 steam flaked corn (360 g/L) and S4 = 0,7 kg DM.day-1 soybean meal. Grazing behavior measurements were taken every 15 days after 9 a day adaptation period, during two consecutive summer grazing cycles. Animal activities were recorded every 5 minutes during day time and 15 minutes during night time throughout a 24 hour period. Supplementation with S2 decreased (P \u3c 0,05) rumination time under a higher grazing residue (R2). Both grazing and rumination time were increased and led to a decreased resting time (P \u3c 0,05) in R2 animals compared with R1
Coherent vortex structures and 3D enstrophy cascade
Existence of 2D enstrophy cascade in a suitable mathematical setting, and
under suitable conditions compatible with 2D turbulence phenomenology, is known
both in the Fourier and in the physical scales. The goal of this paper is to
show that the same geometric condition preventing the formation of
singularities - 1/2-H\"older coherence of the vorticity direction - coupled
with a suitable condition on a modified Kraichnan scale, and under a certain
modulation assumption on evolution of the vorticity, leads to existence of 3D
enstrophy cascade in physical scales of the flow.Comment: 15 pp; final version -- to appear in CM
Robust ferromagnetism in the compressed permanent magnet Sm2Co17
FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPThe compound Sm2CO17 displays magnetic properties amenable to permanent magnet applications owing to both the 3d electrons of Co and the 4f electrons of Sm. The long-standing description of the magnetic interactions between the Sm and Co ions implies a truly ferromagnetic configuration, but some recent calculations challenge this axiom, suggesting at least a propensity for ferrimagnetic behavior. We have used high-pressure synchrotron x-ray techniques to characterize the magnetic and structural properties of Sm2Co17 to reveal a robust ferromagnetic state. The local Sm moment is at most weakly affected by compression, and the ordered moments show a surprising resilience to volumetric compressions of nearly 20%. Density functional theory calculations echo the magnetic robustness of Sm2Co17.9010112FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2013/14338-3We graciously thank K. Visbeck for assistance with DAC preparation and C. Kenney-Benson for assistance with setup at the Advanced Photon Source. This work was performed under LDRD (Tracking Code 12-ERD-013) and under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory (LLNL) under Contract No. DE-AC52-07NA27344. L. S. I. Veiga is supported by FAPESP (SP-Brazil) under Contract No. 2013/14338-3. Portions of this work were performed at Sector 4 and at HPCAT (Sector 16), Advanced Photon Source (APS), Argonne National Laboratory. HPCAT operations are supported by DOE-NNSA under Award No. DE-NA0001974 and DOE-BES under Award No. DE-FG02-99ER45775, with partial instrumentation funding by NSF. APS is supported by DOE-BES, under Contract No. DE-AC02-06CH11357. Beamtime was provided by the General User Proposal system and the Carnegie DOE-Alliance Center (CDAC). Identification of commercial materials or equipment does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose
Viscous-Inviscid Interactions in a Boundary-Layer Flow Induced by a Vortex Array
In this paper we investigate the asymptotic validity of boundary layer
theory. For a flow induced by a periodic row of point-vortices, we compare
Prandtl's solution to Navier-Stokes solutions at different numbers. We
show how Prandtl's solution develops a finite time separation singularity. On
the other hand Navier-Stokes solution is characterized by the presence of two
kinds of viscous-inviscid interactions between the boundary layer and the outer
flow. These interactions can be detected by the analysis of the enstrophy and
of the pressure gradient on the wall. Moreover we apply the complex singularity
tracking method to Prandtl and Navier-Stokes solutions and analyze the previous
interactions from a different perspective
A posteriori error estimates for the virtual element method
An a posteriori error analysis for the virtual element method (VEM) applied to general elliptic problems is presented. The resulting error estimator is of residual-type and applies on very general polygonal/polyhedral meshes. The estimator is fully computable as it relies only on quantities available from the VEM solution, namely its degrees of freedom and element-wise polynomial projection. Upper and lower bounds of the error estimator with respect to the VEM approximation error are proven. The error estimator is used to drive adaptive mesh refinement in a number of test problems. Mesh adaptation is particularly simple to implement since elements with consecutive co-planar edges/faces are allowed and, therefore, locally adapted meshes do not require any local mesh post-processing
Critical analysis of information security culture definitions
This article aims to advance the understanding of information security culture through a critical reflection on the wide-ranging definitions of information security culture in the literature. It uses the hermeneutic approach for conducting literature reviews. The review identifies 16 definitions of information security culture in the literature. Based on the analysis of these definitions, four different views of culture are distinguished. The shared values view highlights the set of cultural value patterns that are shared across the organization. An action-based view highlights the behaviors of individuals in the organization. A mental model view relates to the abstract view of the individual’s thinking on how information security culture must work. Finally, a problem-solving view emphasizes a combination of understanding from shared value-based and action-based views. The paper analyzes and presents the limitations of these four views of information security culture definitions
Use of cloprostenol to synchronize estrus after induction by light program in anestrous dairy goats.
This study aimed to test the possibility to synchronize estrus with cloprostenol in dairy goats submitted to light program, after estrous detection. Both estrous control techniques do not require milk discharge. The sequential association of these two tools can provide synchronous estrus during the non-breeding season, allowing AI to be performed in timed like scheme similar to the breeding season in dairy goats. [Uso de cloprostenol para sincronização do estro após indução por meio de programa de luz em caprinos leiteiros na estação de anestro estacional].Edição dos anais do XXII Congresso Brasileiro de Reprodução Animal (CBRA), Santos, SP, Brasil, maio 2017
Interior regularity criteria for suitable weak solutions of the Navier-Stokes equations
We present new interior regularity criteria for suitable weak solutions of
the 3-D Navier-Stokes equations: a suitable weak solution is regular near an
interior point if either the scaled -norm of the velocity
with , , or the -norm of the
vorticity with , , or the
-norm of the gradient of the vorticity with , , , is sufficiently small near
The usefulness of rapid diagnostic tests in the new context of low malaria transmission in zanzibar.
BACKGROUND\ud
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We assessed if histidine-rich-protein-2 (HRP2) based rapid diagnostic test (RDT) remains an efficient tool for Plasmodium falciparum case detection among fever patients in Zanzibar and if primary health care workers continue to adhere to RDT results in the new epidemiological context of low malaria transmission. Further, we evaluated the performance of RDT within the newly adopted integrated management of childhood illness (IMCI) algorithm in Zanzibar.\ud
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METHODS AND FINDINGS\ud
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We enrolled 3890 patients aged ≥2 months with uncomplicated febrile illness in this health facility based observational study conducted in 12 primary health care facilities in Zanzibar, between May-July 2010. One patient had an inconclusive RDT result. Overall 121/3889 (3.1%) patients were RDT positive. The highest RDT positivity rate, 32/528 (6.1%), was found in children aged 5-14 years. RDT sensitivity and specificity against PCR was 76.5% (95% CI 69.0-83.9%) and 99.9% (95% CI 99.7-100%), and against blood smear microscopy 78.6% (95% CI 70.8-85.1%) and 99.7% (95% CI 99.6-99.9%), respectively. All RDT positive, but only 3/3768 RDT negative patients received anti-malarial treatment. Adherence to RDT results was thus 3887/3889 (99.9%). RDT performed well in the IMCI algorithm with equally high adherence among children <5 years as compared with other age groups.\ud
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CONCLUSIONS\ud
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The sensitivity of HRP-2 based RDT in the hands of health care workers compared with both PCR and microscopy for P. falciparum case detection was relatively low, whereas adherence to test results with anti-malarial treatment was excellent. Moreover, the results provide evidence that RDT can be reliably integrated in IMCI as a tool for improved childhood fever management. However, the relatively low RDT sensitivity highlights the need for improved quality control of RDT use in primary health care facilities, but also for more sensitive point-of-care malaria diagnostic tools in the new epidemiological context of low malaria transmission in Zanzibar.\ud
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TRIAL REGISTRATION\ud
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ClinicalTrials.gov NCT01002066
The Inviscid Limit and Boundary Layers for Navier-Stokes Flows
The validity of the vanishing viscosity limit, that is, whether solutions of
the Navier-Stokes equations modeling viscous incompressible flows converge to
solutions of the Euler equations modeling inviscid incompressible flows as
viscosity approaches zero, is one of the most fundamental issues in
mathematical fluid mechanics. The problem is classified into two categories:
the case when the physical boundary is absent, and the case when the physical
boundary is present and the effect of the boundary layer becomes significant.
The aim of this article is to review recent progress on the mathematical
analysis of this problem in each category.Comment: To appear in "Handbook of Mathematical Analysis in Mechanics of
Viscous Fluids", Y. Giga and A. Novotn\'y Ed., Springer. The final
publication is available at http://www.springerlink.co
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