3,755 research outputs found

    Impact pressures of turbulent high-velocity jets plunging in pools with flat bottom

    Get PDF
    Dynamic pressures created by the impact of high-velocity turbulent jets plunging in a water pool with flat bottom were investigated. Pressure fluctuations were sampled at 1kHz at the jet outlet and at the pool bottom using piezo-resistive pressure transducers, jet velocities of up to 30m/s and pool depth to jet diameter ratios from 2.8 to 11.4. The high-velocity jets entrain air in the pool in conditions similar to prototype applications at water release structures of dams. The intermittent character of plunge pool flows was investigated for shallow and deep pools, based on high order moments and time correlations. Maximum intermittency was observed for pool depths at 5.6 jet diameters, which approximate the core development length. Wall pressure skewness was shown to allow identifying the zone of influence of downward and upward moving current

    Classification of areas using pixel-by-pixel and sample classifiers

    Get PDF
    There are no author-identified significant results in this report

    The Spitzer South Pole Telescope Deep Field Survey: Linking galaxies and halos at z=1.5

    Full text link
    We present an analysis of the clustering of high-redshift galaxies in the recently completed 94 deg2^2 Spitzer-SPT Deep Field survey. Applying flux and color cuts to the mid-infrared photometry efficiently selects galaxies at z1.5z\sim1.5 in the stellar mass range 10101011M10^{10}-10^{11}M_\odot, making this sample the largest used so far to study such a distant population. We measure the angular correlation function in different flux-limited samples at scales >6>6^{\prime \prime} (corresponding to physical distances >0.05>0.05 Mpc) and thereby map the one- and two-halo contributions to the clustering. We fit halo occupation distributions and determine how the central galaxy's stellar mass and satellite occupation depend on the halo mass. We measure a prominent peak in the stellar-to-halo mass ratio at a halo mass of log(Mhalo/M)=12.44±0.08\log(M_{\rm halo} / M_\odot) = 12.44\pm0.08, 4.5 times higher than the z=0z=0 value. This supports the idea of an evolving mass threshold above which star formation is quenched. We estimate the large-scale bias in the range bg=24b_g=2-4 and the satellite fraction to be fsat0.2f_\mathrm{sat}\sim0.2, showing a clear evolution compared to z=0z=0. We also find that, above a given stellar mass limit, the fraction of galaxies that are in similar mass pairs is higher at z=1.5z=1.5 than at z=0z=0. In addition, we measure that this fraction mildly increases with the stellar mass limit at z=1.5z=1.5, which is the opposite of the behavior seen at low-redshift.Comment: 32 pages, 22 figures. Published in MNRA

    The effect of different remineralizing agents on caries-like lesions – a pilot study

    Get PDF
    Poster apresentado no XXV Congresso da Ordem dos Médicos Dentistas, 10-12 Novembro 2016, Porto, PortugalSob uma licença CC-BY-NC - http://creativecommons.org/licenses/by-nc/4.0/Aim: To quantify the surface microhardness of enamel when using different remineralizing agents, after the induction of artificial dental caries.N/

    BEC-BCS crossover in a cold and magnetized two color NJL model

    Get PDF
    The BEC-BCS crossover for a NJL model with diquark interactions is studied in the presence of an external magnetic field. Particular attention is paid to different regularization schemes used in the literature. A thorough comparison of results is performed for the case of a cold and magnetized two-color NJL model. According to our results, the critical chemical potential for the BEC transition exhibits a clear inverse magnetic catalysis effect for magnetic fields in the range 1eB/mπ220 1 \lesssim eB/m_\pi^2 \lesssim 20 . As for the BEC-BCS crossover, the corresponding critical chemical potential is very weakly sensitive to magnetic fields up to eB9 mπ2eB \sim 9\ m_\pi^2, showing a much smaller inverse magnetic catalysis as compared to the BEC transition, and displays a strong magnetic catalysis from this point on.Comment: 15 pages, 8 figures; v2 PRD versio

    Characterization of enamel surface after orthodontic brackets debonding: an in vitro study

    Get PDF
    Poster presented at the SPMicros Congress “Microscopy in Research” - XLVII Annual Congress of the Portuguese Society for Microscopy. Egas Moniz, Monte de Caparica, 9-10 December 2013PEst-OE/CTM-UI0084/2011 grant (Fundação para a Ciência e a Tecnologia

    Characterization of enamel surface after orthodontic brackets debonding: an in vitro study

    Get PDF
    Abstract of the poster presented at the SPMicros Congress “Microscopy in Research” - XLVII Annual Congress of the Portuguese Society for Microscopy. Egas Moniz, Monte de Caparica, 9-10 December 2013.PEst-OE/CTM-UI0084/2011 grant (Fundação para a Ciência e a Tecnologia

    Letter to the editor: Measles outbreak linked to an international dog show in Slovenia - primary cases and chains of transmission identified in Italy, November to December 2014

    Get PDF
    In the letter epidemiological and virological investigations on Italian measles cases associated to a measles outbreak in Slovenia, linked to an international dog show from 8 to 9 November 2014, are described

    Prescribed Fire Plus Grazing Horses: A Sustainable Model to Decrease Fire Hazard in a Mountain Landscape

    Get PDF
    The mountain landscapes of northern Portugal have been modified through rural depopulation and the absence of rangeland management. As such, increased above-ground biomass and higher fire hazard resulted, as well as decreased ecosystem biodiversity. The objectives of the OpentoPreserve Interreg SUDOE project are to evaluate the effects of the combined use of prescribed fire with grazing horses, and also to develop strategies of socio-economic valorization of this model. Concerning the evaluation of prescribed fire and grazing effects, the experimental design consisted of three plots in the Natura 2000 Alvão/Marão Site, respectively Control, Fire x Grazing, and Fire. The Fire plots were burned in early spring and vegetation percent cover and height were measured in all plots in late spring. We have implemented four transects in the three different plots, used the line intercept method and subsequently estimated vegetation volume. This methodology is also applied on Forestation of Agricultural Land with More Silviculture, Silvopasture, Innovation and Value project. Concerning socio-economic valorization, the stakeholders related to the native horse breed, were interviewed and a focus-group was held. The study intends to identify both the benefits resulting from the adoption of a management system that includes the native horse breed, named Garrano, and the main weaknesses related to environmental, economic and social sustainability. Initial results for total vegetation in each plot show a high reduction in vegetation percent cover and its volume in the burned plots (33.5% and 268.3 m3 ha-1) in comparison to the control plot (183.7% and 12862.5 m3 ha-1). Furthermore, a fast recovery was observed in July, mainly of the Pterospartum tridentatum shrub species. Interviews and focus-group results shows the important role of these grazing animals in vegetation control as well as in other ecosystems services, involving an environmental and a socio-economic dimension. A strategy to value contribution to the economy of agricultural holdings has been proposed
    corecore