2,732 research outputs found

    Mr. R. K. Heald, Proprietor of the R. K. Heald Company That Manufactured Agricultural Implements and Was Located at Tenth and River Streets, Sent a Statement to Rev. Albertus C. Van Raalte That His Bill Had Been Paid in Full.

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    Mr. R. K. Heald, proprietor of the R. K. Heald company that manufactured agricultural implements and was located at Tenth and River Streets, sent a statement to Rev. Albertus C. Van Raalte that his bill had been paid in full.https://digitalcommons.hope.edu/vrp_1870s/1123/thumbnail.jp

    HALOGAS: HI Observations and Modeling of the Nearby Edge-on Spiral Galaxy NGC 4565

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    We present 21-cm observations and models of the neutral hydrogen in NGC 4565, a nearby, edge-on spiral galaxy, as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. These models provide insight concerning both the morphology and kinematics of HI above, as well as within, the disk. NGC 4565 exhibits a distinctly warped and asymmetric disk with a flaring layer. Our modeling provides no evidence for a massive, extended HI halo. We see evidence for a bar and associated radial motions. Additionally, there are indications of radial motions within the disk, possibly associated with a ring of higher density. We see a substantial decrease in rotational velocity with height above the plane of the disk (a lag) of -40 +5/-20 km/s/kpc and -30 +5/-30 km s/kpc in the approaching and receding halves, respectively. This lag is only seen within the inner ~4.75' (14.9 kpc) on the approaching half and ~4.25' (13.4 kpc) on the receding, making this a radially shallowing lag, which is now seen in the HI layers of several galaxies. When comparing results for NGC 4565 and those for other galaxies, there are tentative indications of high star formation rate per unit area being associated with the presence of a halo. Finally, HI is found in two companion galaxies, one of which is clearly interacting with NGC 4565.Comment: 17 pages, 16 figures, accepted for publication in the Astrophysical Journal, modified affiliatio

    The Valuation of Unprotected Works: A Case Study of Public Domain Images on Wikipedia

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    Seeking large-scale magnetic fields in a pure-disk dwarf galaxy NGC 2976

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    It is still unknown how magnetic field-generation mechanisms could operate in low-mass dwarf galaxies. Here, we present a detailed study of a nearby pure-disk dwarf galaxy NGC 2976. Unlike previously observed dwarf objects, this galaxy possesses a clearly defined disk. For the purpose of our studies, we performed deep multi-frequency polarimetric observations of NGC 2976 with the VLA and Effelsberg radio telescopes. Additionally, we supplement them with re-imaged data from the WSRT-SINGS survey. The magnetic field morphology discovered in NGC 2976 consists of a southern polarized ridge. This structure does not seem to be due to just a pure large-scale dynamo process (possibly cosmic-ray driven) at work in this object, as indicated by the RM data and dynamo number calculations. Instead, the field of NGC 2976 is modified by past gravitational interactions and possibly also by ram pressure inside the M 81 galaxy group environment. The estimates of total (7 muG) and ordered (3 muG) magnetic field strengths, as well as degree of field order (0.46), which is similar to those observed in spirals, suggest that tidally generated magnetized gas flows can further enhance dynamo action in the object. NGC 2976 is apparently a good candidate for the efficient magnetization of its neighbourhood. It is able to provide an ordered (perhaps also regular) magnetic field into the intergalactic space up to a distance of about 5 kpc. Tidal interactions (and possibly also ram pressure) can lead to the formation of unusual magnetic field morphologies (like polarized ridges) in galaxies out of the star-forming disks, which do not follow any observed component of the interstellar medium (ISM), as observed in NGC 2976. These galaxies are able to provide ordered magnetic fields far out of their main disks.Comment: 16 page

    Lifestyle intervention in individuals with impaired glucose regulation affects Caveolin-1 expression and DNA methylation

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    © 2020, © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Aims: We investigated whether a lifestyle intervention could influence expression and DNA methylation of diabetes-related genes in patients with impaired glucose regulation (IGR), the results were compared to bariatric surgery, considering it an intensive change. Methods: Twenty participants with IGR had adipose tissue biopsy and blood collected pre- and post-lifestyle (6 months) intervention; 12 obese patients had subcutaneous fat taken before and after bariatric surgery. RNA/DNA was extracted from all samples and underwent qPCR. DNA was bisulphite converted and 12 CpG sites of Caveolin-1 (CAV1) promoter were pyrosequenced. Results: lifestyle intervention resulted in opposite direction changes in fat tissue and blood for CAV1 expression and DNA methylation and these changes were correlated between tissues, while no significative differences were found in CAV1 expression after bariatric surgery. Conclusions: Our findings suggest a role for CAV1 in modulating adipocyte function as a consequence of lifestyle changes, as exercises and diet. These results may provide insights into new therapeutic targets for diabetes prevention

    Global modeling of secondary organic aerosol formation from aromatic hydrocarbons: high- vs low-yield pathways

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    Formation of SOA from the aromatic species toluene, xylene, and, for the first time, benzene, is added to a global chemical transport model. A simple mechanism is presented that accounts for competition between low and high-yield pathways of SOA formation, wherein secondary gas-phase products react further with either nitrogen oxide (NO) or hydroperoxy radical (HO2) to yield semi- or non-volatile products, respectively. Aromatic species yield more SOA when they react with OH in regions where the [NO]/[HO2] ratios are lower. The SOA yield thus depends upon the distribution of aromatic emissions, with biomass burning emissions being in areas with lower [NO]/[HO2] ratios, and the reactivity of the aromatic with respect to OH, as a lower initial reactivity allows transport away from industrial source regions, where [NO]/[HO2] ratios are higher, to more remote regions, where this ratio is lower and, hence, the ultimate yield of SOA is higher. As a result, benzene is estimated to be the most important aromatic species with regards to formation of SOA, with a total production nearly equal that of toluene and xylene combined. In total, while only 39% percent of the aromatic species react via the low-NOx pathway, 72% of the aromatic SOA is formed via this mechanism. Predicted SOA concentrations from aromatics in the Eastern United States and Eastern Europe are actually largest during the summer, when the [NO]/[HO2] ratio is lower. Global production of SOA from aromatic sources is estimated at 3.5 Tg/yr, resulting in a global burden of 0.08 Tg, twice as large as previous estimates. The contribution of these largely anthropogenic sources to global SOA is still small relative to biogenic sources, which are estimated to comprise 90% of the global SOA burden, about half of which comes from isoprene. Compared to recent observations, it would appear there are additional pathways beyond those accounted for here for production of anthropogenic SOA. However, owing to differences in spatial distributions of sources and seasons of peak production, there are still regions in which aromatic SOA produced via the mechanisms identified here are predicted to contribute substantially to, and even dominate, the local SOA concentrations, such as outflow regions from North America and South East Asia during the wintertime, though total SOA concentrations there are small (~0.1 μg/m^³)

    Copyright and the Value of the Public Domain: an empirical assessment

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    This Report is the outcome of a knowledge exchange scheme which brings together academics (from the disciplines of law, media & communication studies, management and economics), policy makers from the Intellectual Property Office (an executive agency of the Department for Business, Innovation and Skills) and media businesses (in particular transmedia SMEs) to generate and disseminate new knowledge about the use of public domain works

    The SKA view of the Neutral Interstellar Medium in Galaxies

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    Two major questions in galaxy evolution are how star-formation on small scales leads to global scaling laws and how galaxies acquire sufficient gas to sustain their star formation rates. HI observations with high angular resolution and with sensitivity to very low column densities are some of the important observational ingredients that are currently still missing. Answers to these questions are necessary for a correct interpretation of observations of galaxy evolution in the high-redshift universe and will provide crucial input for the sub-grid physics in hydrodynamical simulations of galaxy evolutions. In this chapter we discuss the progress that will be made with the SKA using targeted observations of nearby individual disk and dwarf galaxies.Comment: 22 pages, 4 figures, to appear as part of 'Neutral Hydrogen' in Proceedings 'Advancing Astrophysics with the SKA (AASKA14)', PoS(AASKA14)12

    HALOGAS: HI Observations and Modeling of the Nearby Edge-on Spiral Galaxy NGC 4244

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    We present 21-cm observations and models of the HI kinematics and distribution of NGC 4244, a nearby edge-on Scd galaxy observed as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. Our models give insight into the HI kinematics and distribution with an emphasis on the potential existence of extra-planar gas as well as a negative gradient in rotational velocity with height above the plane of the disk (a lag). Our models yield strong evidence against a significantly extended halo and instead favor a warp component along the line of sight as an explanation for some of the observed thickening of the disk. Based on these models, we detect a lag of -9 +3/-2 km s-1 kpc-1 in the approaching half and -9 +/-2 km s-1 kpc-1 in the receding half. This lag decreases in magnitude to -5+/-2 km s-1 kpc-1 and -4+/-2 km s-1 kpc-1 near a radius of 10 kpc in the approaching and receding halves respectively. Additionally, we detect several distinct morphological and kinematic features including a shell that is probably driven by star formation within the disk.Comment: 18 pages, 14 figures, Full resolution version may be found at: http://www.astron.nl/halogas/papers/NGC4244.Zschaechner.arXiv.p
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