9,137 research outputs found

    Pathobiochemical mechanisms in inflammation

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    Protons as the prime contributors to the storm time ring current

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    Following a large magnetic storm (17 June 1972), Explorer 45 measured the equatorial particle populations and magnetic field. Using data obtained during the symmetic recovery phase, it is shown that through a series of self-consistent calculations, the measured protons with energies from 1 to 872 keV, can account for the observed ring current magnetic effects within experimental uncertainities. This enables an upper limit to be set for the heavy ion contribution to the storm time ring current

    Optimization conditions of UV-C radiation combined with ultrasound-assisted extraction of cherry tomato (Lycopersicon esculentum) lycopene extract

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    The aim of this work was to study the effect of UV-C radiation on ultrasound assisted extraction (UAE) of cherry tomato bioactive compounds. Cherry tomatoes were exposed to two UV-C radiation doses (0.5 and 1.0 J cm−2 ) and stored at 20 ± 0.5 oC for 7 days. Next, they were lyophilized, and the bioactive compounds were extracted by UAE at 20 KHz. To evaluate the effectiveness of the extraction process of the bioactive compounds, a CCRD (central composite rotational design) was used together with RSM (response surface methodology), for extraction times from 4 to 12 minutes and concentrations (g of lyophilized product / L of ethanol) of 1:10, 1:20 and 1:30. The extracts obtained from the irradiated tomatoes presented 5.8 times more lycopene content than the controls and higher antioxidant activity was obtained for 4 and 8 min, in the concentrations 1:10 and 1:20 (m v−1). Through numerical model optimization, optimal extraction conditions were obtained. The results demonstrated that by previously irradiating tomatoes with UV-C light, the UAE yielded considerably higher amounts of lycopene and other bioactives.CNPq (National Council of Technological and Scientific Development, Brazil), Erasmus Mundus action 2; Fellow Mundus Project; Department of Chemical Engineering and Food Engineering (UFSC - Brazil) and the Department of Food Engineering (UAlg - Portugal) .info:eu-repo/semantics/publishedVersio

    Satellite detection of vegetative damage and alteration caused by pollutants emitted by a zinc smelter

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    The author has identified the following significant results. Field observations and data collected by low flying aircraft were used to verify the accuracy of maps produced from the satellite data. Although areas of vegetation as small as six acres can accurately be detected, a white pine stand that was severely damaged by sulfur dioxide could not be differentiated from a healthy white pine stand because spectral differences were not large enough. When winter data were used to eliminate interference from herbaceous and deciduous vegetation, the damage was still undetectable. The analysis was able to produce a character map that accurately delineated areas of vegetative alteration due to high zinc levels accumulating in the soil. The map depicted a distinct gradient of less damage and alteration as the distance from the smelter increased. Although the satellite data will probably not be useful for detecting small acreages of damaged vegetation, it is concluded that the data may be very useful as an inventory tool to detect and delineate large vegetative areas possessing differing spectral signatures

    Transport Properties of a Chain of Anharmonic Oscillators with random flip of velocities

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    We consider the stationary states of a chain of nn anharmonic coupled oscillators, whose deterministic hamiltonian dynamics is perturbed by random independent sign change of the velocities (a random mechanism that conserve energy). The extremities are coupled to thermostats at different temperature TT_\ell and TrT_r and subject to constant forces τ\tau_\ell and τr\tau_r. If the forces differ ττr\tau_\ell \neq \tau_r the center of mass of the system will move of a speed VsV_s inducing a tension gradient inside the system. Our aim is to see the influence of the tension gradient on the thermal conductivity. We investigate the entropy production properties of the stationary states, and we prove the existence of the Onsager matrix defined by Green-kubo formulas (linear response). We also prove some explicit bounds on the thermal conductivity, depending on the temperature.Comment: Published version: J Stat Phys (2011) 145:1224-1255 DOI 10.1007/s10955-011-0385-

    Differential Parental Care by Adult Mountain Plovers, Charadrius montanus

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    We studied chick survival of the Mountain Plover (Charadrius montanus) in Montana and found that chicks tended by females had higher survival rates than chicks tended by males, and that chick survival generally increased during the nesting season. Differences in chick survival were most pronounced early in the nesting season, and may be related to a larger sample of nests during this period. When compared to information about the nest survival of male- and female-tended plover nests, our chick data suggest a trade-off for adult plovers between the egg and chick phases of reproduction. Because Mountain Plover pairs have clutches at two nests at two different locations and show differential success between the sexes during the egg and chick phases, we offer that the Mountain Plover breeding system favours optimizing annual recruitment in a dynamic ecologic setting driven by annually unpredictable drought, grazing, and predation pressures
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