Wall shear stress from jetting cavitation bubbles

The collapse of a cavitation bubble near a rigid boundary induces a high-speed transient jet accelerating liquid onto the boundary. The shear flow produced by this event has many applications, examples of which are surface cleaning, cell membrane poration and enhanced cooling. Yet the magnitude and spatio-temporal distribution of the wall shear stress are not well understood, neither experimentally nor by simulations. Here we solve the flow in the boundary layer using an axisymmetric compressible volume-of-fluid solver from the OpenFOAM framework and discuss the resulting wall shear stress generated for a non-dimensional distance,γ = 1.0 (γ = h/Rmax, where h is the distance of the initial bubble centre to the boundary, and Rmax is the maximum spherical equivalent radius of the bubble). The calculation of the wall shear stress is found to be reliable once the flow region with constant shear rate in the boundary layer is determined. Very high wall shear stresses of 100 kPa are found during the early spreading of the jet, followed by complex flows composed of annular stagnation rings and secondary vortices. Although the simulated bubble dynamics agrees very well with experiments, we obtain only qualitative agreement with experiments due to inherent experimental challenges

On the future of Gamma-Ray Burst Cosmology

With the understanding that the enigmatic Gamma-Ray Burts (GRBs) are beamed explosions, and with the recently discovered ``Ghirlanda-relation'', the dream of using GRBs as cosmological yardsticks may have come a few steps closer to reality. Assuming the Ghirlanda-relation is real, we have investigated possible constraints on cosmological parameters using a simulated future sample of a large number of GRBs inspired by the ongoing SWIFT mission. Comparing with constraints from a future sample of Type Ia supernovae, we find that GRBs are not efficient in constraining the amount of dark energy or its equation of state. The main reason for this is that very few bursts are available at low redshifts.Comment: 5 pages, 2 figures, matches version accepted for publication in JCA

Constraining primordial non-Gaussianity with cosmological weak lensing: shear and flexion

We examine the cosmological constraining power of future large-scale weak lensing surveys on the model of \emph{Euclid}, with particular reference to primordial non-Gaussianity. Our analysis considers several different estimators of the projected matter power spectrum, based on both shear and flexion, for which we review the covariances and Fisher matrices. The bounds provided by cosmic shear alone for the local bispectrum shape, marginalized over $\sigma_8$, are at the level of $\Delta f_\mathrm{NL} \sim 100$. We consider three additional bispectrum shapes, for which the cosmic shear constraints range from $\Delta f_\mathrm{NL}\sim 340$ (equilateral shape) up to $\Delta f_\mathrm{NL}\sim 500$ (orthogonal shape). The competitiveness of cosmic flexion constraints against cosmic shear ones depends on the galaxy intrinsic flexion noise, that is still virtually unconstrained. Adopting the very high value that has been occasionally used in the literature results in the flexion contribution being basically negligible with respect to the shear one, and for realistic configurations the former does not improve significantly the constraining power of the latter. Since the flexion noise decreases with decreasing scale, by extending the analysis up to $\ell_\mathrm{max} = 20,000$ cosmic flexion, while being still subdominant, improves the shear constraints by $\sim 10$ when added. However on such small scales the highly non-linear clustering of matter and the impact of baryonic physics make any error estimation uncertain. By considering lower, and possibly more realistic, values of the flexion intrinsic shape noise results in flexion constraining power being a factor of $\sim 2$ better than that of shear, and the bounds on $\sigma_8$ and $f_\mathrm{NL}$ being improved by a factor of $\sim 3$ upon their combination. (abridged)Comment: 30 pages, 4 figures, 4 tables. To appear on JCA

Monitoramento de Helicoverpa armigera na cultura da soja, em Mato Grosso do Sul.

bitstream/item/136410/1/31-Eunice-Monitoramento.pd

Is the treatment with biological or non-biological DMARDS a modifier of periodontal condition in patients with rheumatoid arthritis?

Background and objective: Experimental models suggest the use of different therapy protocols in rheumatoid arthritis (RA) as modulators on periodontal condition. This study evaluated the effects of conventional drug treatment and anti-TNF therapy in patients with RA on microbiological and periodontal condition, establishing the association of markers of periodontal infection with indexes of rheumatic activity. Materials and methods: One hundred seventy nine individuals with RA were evaluated (62 with anti-TNF-. and 115 with only DMARDs). The periodontal evaluation included plaque and gingival indexes, bleeding on probing (BOP), clinical attachment loss (CAL), pocket depth (PD) and subgingival plaque samples for microbiological analysis. Rheumatologic evaluations included a clinical examination, rheumatoid factor (RF), antibodies against cyclic-citrullinated peptides (ACPAs), and activity markers (DAS28-ERS), high sensitive C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR). Results: Anti-TNF-alpha therapy influenced periodontal microbiota with a higher frequency of T. denticola (p=0.01). Methotrexate combined with leflunomide exhibited a higher extension of CAL (p=0.005), and anti-TNF-alpha therapy with methotrexate was associated with a lower extension of CAL (p=0.05). The use of corticosteroids exerted a protective effect on the number of teeth (p=0.027). The type of DMARD affected P. gingivalis, T. forsythia and E. nodatum presence. Elevated ACPAs titers were associated with the presence of red complex periodontal pathogens (p=0.025). Bleeding on probing was associated with elevated CPR levels (p=0.05), and ESR was associated with a greater PD (p=0.044) and presence of red complex (p=0.030). Conclusion: Different pharmacological treatments for RA affect the clinical condition and subgingival microbiota

Spectral variability of a sample of extreme variability quasars and implications for the MgII broad-line region

FINANCIADORA DE ESTUDOS E PROJETOS - FINEPFUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQWe present new Gemini/GMOS optical spectroscopy of 16 extreme variability quasars (EVQs) that dimmed bymore than 1.5mag in the g band between the Sloan Digital Sky Survey (SDSS) and the Dark Energy Survey epochs (separated by a few years in the quasar res493457735787FINANCIADORA DE ESTUDOS E PROJETOS - FINEPFUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFINANCIADORA DE ESTUDOS E PROJETOS - FINEPFUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQSem informaçãoSem informação465376/2014-2We thank the referee, Andy Lawrence, for useful comments that improved the manuscript. QY and YS acknowledge support from an Alfred P. Sloan Research Fellowship (YS) and NSF grant AST-1715579. We thank Patrick Hall, Tamara Davis, Shu Wang, and Hengxiao G

Simulation of the CMS Resistive Plate Chambers

The Resistive Plate Chamber (RPC) muon subsystem contributes significantly to the formation of the trigger decision and reconstruction of the muon trajectory parameters. Simulation of the RPC response is a crucial part of the entire CMS Monte Carlo software and directly influences the final physical results. An algorithm based on the parametrization of RPC efficiency, noise, cluster size and timing for every strip has been developed. Experimental data obtained from cosmic and proton-proton collisions at $\sqrt{s}=7$ TeV have been used for determination of the parameters. A dedicated validation procedure has been developed. A good agreement between the simulated and experimental data has been achieved.Comment: to be published in JINS

Ocorrência de insetos-pragas e de seus predadores em diferentes sistemas de produção de soja.

bitstream/item/148546/1/27-ocorrencia.pd

Web-based monitoring tools for Resistive Plate Chambers in the CMS experiment at CERN

The Resistive Plate Chambers (RPC) are used in the CMS experiment at the trigger level and also in the standard offline muon reconstruction. In order to guarantee the quality of the data collected and to monitor online the detector performance, a set of tools has been developed in CMS which is heavily used in the RPC system. The Web-based monitoring (WBM) is a set of java servlets that allows users to check the performance of the hardware during data taking, providing distributions and history plots of all the parameters. The functionalities of the RPC WBM monitoring tools are presented along with studies of the detector performance as a function of growing luminosity and environmental conditions that are tracked over time

Operational experience with the GEM detector assembly lines for the CMS forward muon upgrade

The CMS Collaboration has been developing large-area triple-gas electron multiplier (GEM) detectors to be installed in the muon Endcap regions of the CMS experiment in 2019 to maintain forward muon trigger and tracking performance at the High-Luminosity upgrade of the Large Hadron Collider (LHC); 10 preproduction detectors were built at CERN to commission the first assembly line and the quality controls (QCs). These were installed in the CMS detector in early 2017 and participated in the 2017 LHC run. The collaboration has prepared several additional assembly and QC lines for distributed mass production of 160 GEM detectors at various sites worldwide. In 2017, these additional production sites have optimized construction techniques and QC procedures and validated them against common specifications by constructing additional preproduction detectors. Using the specific experience from one production site as an example, we discuss how the QCs make use of independent hardware and trained personnel to ensure fast and reliable production. Preliminary results on the construction status of CMS GEM detectors are presented with details of the assembly sites involvement