4,764 research outputs found

    A metabolic study of the isolated perfused snake liver

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    A metabolic study was made on the isolated, perfused liver of Natrix fasciata fasciata (Linnaeus, 1776). Uric acid production, perfusate protein levels, serum protein patterns, perfusate glucose levels, and bile production were evaluated in this study as criteria of liver function. The perfused liver was found to produce uric acid up through the fourth hour of perfusion. No significant differences (between the perfusions) were found in uric acid production/ gm of liver tissue. Perfusate protein and glucose levels were found to be of a fluctuating or cyclic nature. There was found to be an inverse relationship between these two levels: that is, a rise in the protein level was accompanied by a characteristic decrease in the glucose level, the reverse also holding true. Also, both levels were found to be inversely related to liver weight. Plasma protein pattern studies showed that definite changes were produced within certain specific bands which corresponded to the fluctuations found in the total protein levels. The chemical nature of these bands was also determined. Bile production was recorded in onzy two. of the five perfusions cecause of the difficulty encountered in cannulating the minute bile duct. Histological studies revealed some necrosis of the perfused liver tissue. It was concluded that the isolated liver of N. fasciata fasciata could be perfused in this system from 4 to 5 hours without significant decreases in the functional activities that were examined

    A Canadian Perspective

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    This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Advocates the need to continue innovative efforts to provide convenient access to credible information about known existing clinical trials

    The Advanced Reusable Technologies Project

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    Currently, NASA and its industry partners are performing ground testing of hydrogen-fueled rocket based combined-cycle flowpaths. Successful ramjet and scramjet testing at Mach 6 and scramjet testing at Mach 8 have been performed. Cold flow mixing tests have also been successfully performed as have inlet operability tests. Additional testing of RBCC flowpaths at air augmented rocket and rocket only modes is underway

    NuSTAR hard X-ray data and Gemini 3D spectra reveal powerful AGN and outflow histories in two low-redshift Lyman-α\alpha blobs

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    We have shown that Lyman-α\alpha blobs (LABs) may still exist even at z∼0.3z\sim0.3, about 7 billion years later than most other LABs known (Schirmer et al. 2016). Their luminous Lyα\alpha and [OIII] emitters at z∼0.3z\sim0.3 offer new insights into the ionization mechanism. This paper focuses on the two X-ray brightest LABs at z∼0.3z\sim0.3, SDSS J0113++0106 (J0113) and SDSS J1155−-0147 (J1155), comparable in size and luminosity to `B1', one of the best-studied LABs at z≳z \gtrsim 2. Our NuSTAR hard X-ray (3--30 keV) observations reveal powerful active galactic nuclei (AGN) with L2−10  keV=(0.5L_{2-10{\;\rm keV}}=(0.5--3)×10443)\times10^{44} erg cm−2^{-2} s−1^{-1}. J0113 also faded by a factor of ∼5\sim 5 between 2014 and 2016, emphasizing that variable AGN may cause apparent ionization deficits in LABs. Joint spectral analyses including Chandra data constrain column densities of NH=5.1−3.3+3.1×1023N_{\rm H}=5.1^{+3.1}_{-3.3}\times10^{23} cm−2^{-2} (J0113) and NH=6.0−1.1+1.4×1022N_{\rm H}=6.0^{+1.4}_{-1.1}\times10^{22} cm−2^{-2} (J1155). J0113 is likely buried in a torus with a narrow ionization cone, but ionizing radiation is also leaking in other directions as revealed by our Gemini/GMOS 3D spectroscopy. The latter shows a bipolar outflow over 1010 kpc, with a peculiar velocity profile that is best explained by AGN flickering. X-ray analysis of J1155 reveals a weakly absorbed AGN that may ionize over a wide solid angle, consistent with our 3D spectra. Extinction corrected [OIII] log-luminosities are high, ∼43.6\sim43.6. The velocity dispersions are low, ∼100\sim100--150150 km s−1^{-1}, even at the AGN positions. We argue that this is a combination of high extinction hiding the turbulent gas, and previous outflows that have cleared the escape paths for their successors.Comment: 15 pages, 17 Figures, accepted for publication in Ap

    Valuing Avoided Soil Erosion by Considering Private and Public Net Benefits

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    The population in New Zealand is expected to increase to over five million by the mid 2020’s from the current level of 4.3 million (Statistics New Zealand, 2009). An increasing demand for primary produce as a result may put pressure on marginal land to be farmed. Understanding the economic value of avoided erosion in New Zealand is therefore an important factor in policy making to optimise the soil related activities in the economy. Establishing a methodology for estimating the economic value of avoided soil erosion is the first step in assessing the problem. This study uses the future forest scenarios developed by Scion to identify potential afforestation areas and thereby compare the current erosion/sedimentation status under current land-use (non woody vegetation) with potential future afforestation. The study aims to quantify the incremental public and private net benefits from the change in scenario. The notion has come under different headings in the literature, such as on-site and off-site erosion effects or sediment and soil erosion effects, all of which recognize the importance of separation of effects to avoid double-counting. The separation into public and private benefits and costs in this case, while avoiding double-counting, will also help identify appropriate policy instruments to avoid soil erosion damage using the private and public net benefit framework (Pannell, 2008).Environmental Economics and Policy, Land Economics/Use,

    Risk Bearing in Individual and Occupational Pension Plans

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    Soil Shear Strength Losses In Two Fresh Marshes With Variable Increases In N And P Loading

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    We measured soil shear strength (SSS) from 2009 to 2018 in two hydrologically distinct freshwater marshes dominated by Panicum hemitomon after nitrogen (N) and phosphorous (P) were applied to the surface in spring. The SSS averaged over 100-cm depth in the floating and anchored marshes declined up to 30% throughout the profiles and with no apparent differences in the effects of the low, medium, and high N + P dosing. Plots with only N or P additions exhibited significant changes in SSS at individual depths below 40 cm for the anchored marsh, but not the floating marsh. The average SSS for the anchored marsh over the entire 100 cm profile declined when N and P were added separately or together. At the floating marsh, however, the SSS decreased when N and P were added in combination, or P alone, but not for the N addition. Increasing nutrient availability to these freshwater marsh soils makes them weaker, and perhaps lost if eroded or uplifted by buoyant forces during storms. These results are consistent with results from multi-year experiments demonstrating higher decomposition rates, greenhouse gas emissions, and carbon losses in wetlands following increased nutrient availability
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