Vanishing Viscosity Limits and Boundary Layers for Circularly Symmetric 2D Flows

We continue the work of Lopes Filho, Mazzucato and Nussenzveig Lopes [LMN], on the vanishing viscosity limit of circularly symmetric viscous flow in a disk with rotating boundary, shown there to converge to the inviscid limit in $L^2$-norm as long as the prescribed angular velocity $\alpha(t)$ of the boundary has bounded total variation. Here we establish convergence in stronger $L^2$ and $L^p$-Sobolev spaces, allow for more singular angular velocities $\alpha$, and address the issue of analyzing the behavior of the boundary layer. This includes an analysis of concentration of vorticity in the vanishing viscosity limit. We also consider such flows on an annulus, whose two boundary components rotate independently. [LMN] Lopes Filho, M. C., Mazzucato, A. L. and Nussenzveig Lopes, H. J., Vanishing viscosity limit for incompressible flow inside a rotating circle, preprint 2006

Testing demand responsive shared transport services via agent-based simulations

Demand Responsive Shared Transport DRST services take advantage of Information and Communication Technologies ICT, to provide on demand transport services booking in real time a ride on a shared vehicle. In this paper, an agent-based model ABM is presented to test different the feasibility of different service configurations in a real context. First results show the impact of route choice strategy on the system performance

Ocorrência de bactérias diazotróficas e fungos micorrízicos arbusculares na cultura da mandioca

Este trabalho teve como objetivo avaliar a ocorrência, isolar e identificar fungos micorrízicos arbusculares associados à cultura da mandioca (Manihot esculenta). Amostras de solo rizosférico e de várias partes da planta (raízes, tubérculos, manivas e folhas) de locais nos Estados do Rio de Janeiro, São Paulo e Paraná, foram inoculadas nos meios LGI-P, NFb-malato e NFb-GOC, avaliando-se o número mais provável de células e a atividade de redução de acetileno. Bactérias diazotróficas foram isoladas de todas as partes da planta, com exceção das folhas, sendo identificadas como Klebsiella sp., Azospirillum lipoferum e uma bactéria denominada "E", provavelmente pertencente ao gênero Burkholderia. A Bactéria E acumulou de 7,63 mg a 14,84 mg de N/g de C em meio semi-sólido, isento de N, e conseguiu manter a capacidade de fixação biológica de N, mesmo após uma dezena de repicagens consecutivas. A colonização micorrízica variou de 31% a 69%, e a densidade de esporos de 10 a 384 esporos/100 mL de solo, predominando as espécies Entrophospora colombiana e Acaulospora scrobiculata no Rio de Janeiro, A. scrobiculata e Scutellospora heterogama no Paraná e em Piracicaba (São Paulo) e A. appendicula e S. pellucida em Campinas (São Paulo)

Antimicrobial resistance patterns of Salmonella enterica subsp. enterica serovar Derby and Typhimurium isolated from pigs slaughtered in southern Brazil

Salmonella enterica subsp. enterica serovar (S.) Derby and S. Typhimurium were commonly isolated from slaughter pigs and pork. Thus, the monitoring of the resistance profile exhibited by strains of both serovars should be regularly conducted. This study aimed to assess the antimicrobial resistance pattern of strains isolated form pig carcasses and to investigate the genetic relatedness with isolates from intestinal content and lairage environment. Thirty-four S. Derby and seventeen S. Typhimurium strains isolated from carcasses (n=30), intestinal contents (n=16), and lairage environment (n=3) were tested. The antimicrobial resistance was determined by the agar disk diffusion test according to the document M31-A2 of the CLSI using twelve antimicrobials

Experimental determination of the non-extensive entropic parameter qq

We show how to extract the $q$ parameter from experimental data, considering an inhomogeneous magnetic system composed by many Maxwell-Boltzmann homogeneous parts, which after integration over the whole system recover the Tsallis non-extensivity. Analyzing the cluster distribution of La$_{0.7}$Sr$_{0.3}$MnO$_{3}$ manganite, obtained through scanning tunnelling spectroscopy, we measure the $q$ parameter and predict the bulk magnetization with good accuracy. The connection between the Griffiths phase and non-extensivity is also considered. We conclude that the entropic parameter embodies information about the dynamics, the key role to describe complex systems.Comment: Submitted to Phys. Rev. Let

Resposta do arroz apura, à adubação NPK, sob regime de irrigação natural (várzea do Rio Caeté - município de Bragança-PA).

bitstream/item/114592/1/COMUNICADO-TECNICO-14.pdfPublicado também na serie Comunicado Técnico do IPEAN, n. 14