1,127 research outputs found

    Microflanging of CuZn30 Specimens Using Electromagnetic Forming

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    In this research, electro-magnetic (EM) forming was investigated as an alternative process to form microscale components. Both EM and quasi-static flanging experiments were conducted with CuZn30 specimens of 0.127, 0.508 and 1.588 mm thicknesses that were heat treated to achieve 2 and 10 grains through the thickness to assess this parameter. Results from the quasi-static tests showed that as the sample size decreased with a constant grain size through thickness ratio, the springback angle increased. For the 0.127mm and 0.508mm thickness specimens, the EM results showed that the flanging angle increased as the power input increased from 1.7 to 3.7 kJ. For 3.7 kJ energies and above, complete 90 degree flanging with no springback was achieved for the 0.508mm specimens. However, EM flanging could not be achieved for the 1.588mm case. Microhardness testing conducted on specimens of similar flanging angles yielded no observable change in deformation between the EM and quasi-static processes for the 0.508mm specimens

    Relationship between red blood cell lifespan and endogenous carbon monoxide in the common bottlenose dolphin and beluga

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    Certain deep-diving marine mammals (i.e., northern elephant seal (Mirounga angustirosis), Weddell seal (Leptonychotes weddellii)) have blood carbon monoxide (CO) levels that are comparable to those of chronic cigarette smokers. Most CO produced in humans is a by-product of heme degradation, which is released when red blood cells (RBC) are destroyed. Elevated CO can occur in humans when RBC lifespan decreases. The contribution of RBC turnover to CO concentrations in marine mammals is unknown. Here, we report the first RBC lifespans in two healthy, marine mammal species with different diving capacities and heme stores, the shallow diving bottlenose dolphin (Tursiops truncatus) and deep-diving beluga (Delphinapterus leucas) and relate the lifespans to the levels of CO in blood and breath. The belugas, with high blood heme stores, had the longest mean RBC lifespan compared to humans and bottlenose dolphins. Both cetacean species were found to have three times higher blood CO content compared to humans. The estimated CO production rate from heme degradation indicates some marine mammals may have additional mechanisms for CO production, or delay CO removal from the body, potentially from long duration breath-holds

    The Lantern Vol. 7, No. 2, March 1939

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    • Editorial • Easter Eggs • Fever • Sonnets to the Planet We Call Earth • Asking Her Father • New Hampshire Ghost Story • Mary • On Approaching Death • On Turning Over a New Leaf • In Defense of Americanism • What is this Love? • Martyrs of Progress • Recurring • Splintershttps://digitalcommons.ursinus.edu/lantern/1013/thumbnail.jp

    The Lantern Vol. 7, No. 2, March 1939

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    • Editorial • Easter Eggs • Fever • Sonnets to the Planet We Call Earth • Asking Her Father • New Hampshire Ghost Story • Mary • On Approaching Death • On Turning Over a New Leaf • In Defense of Americanism • What is this Love? • Martyrs of Progress • Recurring • Splintershttps://digitalcommons.ursinus.edu/lantern/1013/thumbnail.jp

    Atomic Resonance and Scattering

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    Contains reports on four research projects.U.S. Air Force - Office of Scientific Research (Grant AFOSR-76-2972)National Science Foundation (Grant CHE79-02967)National Science Foundation (Grant PHY79-09743)Joint Services Electronics Program (Contract DAAG29-78-C-0020)Joint Services Electronics Program (Contract DAAG29-80-C-0104

    The Lantern Vol. 6, No. 1, December 1937

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    • After Thinking Things Over • Ho! Ho! The Mistletoe! • Unrealized Dreams • Two Preeminent Victorians • The Thing • Progression • It Wasn\u27t in the Lines • He Was the Most Perfect Man • College (C)lasses • Robins and Roses • The Commuter • When the Rose is Dead • Truth in Print • Alias Mike Romanoff • Winslow Homer • When I Was Young • Maurice Evans, a Great Shakespearean • Among Our Contributors • Of Manx and Man • A Sanguinary Pirate • Conversation Has an Adventure • Ursinus\u27 Neediest Casehttps://digitalcommons.ursinus.edu/lantern/1016/thumbnail.jp

    Diacylglycerol lipase beta inhibition reverses nociceptive behaviour in mouse models of inflammatory and neuropathic pain

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    Background and PurposeInhibition of diacylglycerol lipase (DGL) prevents LPS-induced pro-inflammatory responses in mouse peritoneal macrophages. Thus, the present study tested whether DGL inhibition reverses allodynic responses of mice in the LPS model of inflammatory pain, as well as in neuropathic pain models. Experimental ApproachInitial experiments examined the cellular expression of DGL and inflammatory mediators within the LPS-injected paw pad. DAGL- (-/-) mice or wild-type mice treated with the DGL inhibitor KT109 were assessed in the LPS model of inflammatory pain. Additional studies examined the locus of action for KT109-induced antinociception, its efficacy in chronic constrictive injury (CCI) of sciatic nerve and chemotherapy-induced neuropathic pain (CINP) models. Key ResultsIntraplantar LPS evoked mechanical allodynia that was associated with increased expression of DGL, which was co-localized with increased TNF- and prostaglandins in paws. DAGL- (-/-) mice or KT109-treated wild-type mice displayed reductions in LPS-induced allodynia. Repeated KT109 administration prevented the expression of LPS-induced allodynia, without evidence of tolerance. Intraplantar injection of KT109 into the LPS-treated paw, but not the contralateral paw, reversed the allodynic responses. However, i.c.v. or i.t. administration of KT109 did not alter LPS-induced allodynia. Finally, KT109 also reversed allodynia in the CCI and CINP models and lacked discernible side effects (e.g. gross motor deficits, anxiogenic behaviour or gastric ulcers). Conclusions and ImplicationsThese findings suggest that local inhibition of DGL at the site of inflammation represents a novel avenue to treat pathological pain, with no apparent untoward side effects.United States Department of Health & Human Services - DA009789 - DA017259 - DA032933 - DA033934-01A1 DA035864 - DA038493-01A1National Institutes of Health (NIH) - USANIH-NINDS Center core grant - 5P30NS047463United States Department of Health & Human ServicesNational Institutes of Health (NIH) - USA - P30NS047463NIH National Institute of Neurological Disorders & Stroke (NINDS)United States Department of Health & Human ServicesNational Institutes of Health (NIH) - USA - R01DA032933 - K99DA035864 - P01DA017259 - P01DA009789 - F32DA038493 - R00DA035864 - P30DA033934NIH National Institute on Drug Abuse (NIDA)European Commissio

    Diverse styles of submarine venting on the ultraslow spreading Mid-Cayman Rise

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    Author Posting. © The Authors, 2010. This is the author's version of the work. It is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of America 107 (2010): 14020-14025, doi:10.1073/pnas.1009205107.Thirty years after the first discovery of high-temperature submarine venting, the vast majority of the global Mid Ocean Ridge remains unexplored for hydrothermal activity. Of particular interest are the world’s ultra-slow spreading ridges which were the last to be demonstrated to host high-temperature venting, but may host systems particularly relevant to pre-biotic chemistry and the origins of life. Here we report first evidence for diverse and very deep hydrothermal vents along the ~110 km long, ultra-slow spreading Mid-Cayman Rise. Our data indicate that the Mid- Cayman Rise hosts at least three discrete hydrothermal sites, each representing a different type of water-rock interaction, including both mafic and ultra-mafic systems and, at ~5000 m, the deepest known hydrothermal vent. Although submarine hydrothermal circulation, in which seawater percolates through and reacts with host lithologies, occurs on all mid-ocean ridges, the diversity of vent-types identified here and their relative geographic isolation make the Mid-Cayman Rise unique in the oceans. These new sites offer prospects for: an expanded range of vent-fluid compositions; varieties of abiotic organic chemical synthesis and extremophile microorganisms; and unparalleled faunal biodiversity - all in close proximity.This research was funded through NASA (ASTEP) and WHOI (Ocean Ridge Initiative)

    Caribbean-wide decline in carbonate production threatens coral reef growth

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    This a post-print, author-produced version of an article accepted for publication in Nature Communications. Copyright © 2013 Nature Publishing Group . The definitive version is available at http://www.nature.com/ncomms/journal/v4/n1/full/ncomms2409.htmlGlobal-scale deteriorations in coral reef health have caused major shifts in species composition. One projected consequence is a lowering of reef carbonate production rates, potentially impairing reef growth, compromising ecosystem functionality and ultimately leading to net reef erosion. Here, using measures of gross and net carbonate production and erosion from 19 Caribbean reefs, we show that contemporary carbonate production rates are now substantially below historical (mid- to late-Holocene) values. On average, current production rates are reduced by at least 50%, and 37% of surveyed sites were net erosional. Calculated accretion rates (mm year(-1)) for shallow fore-reef habitats are also close to an order of magnitude lower than Holocene averages. A live coral cover threshold of ~10% appears critical to maintaining positive production states. Below this ecological threshold carbonate budgets typically become net negative and threaten reef accretion. Collectively, these data suggest that recent ecological declines are now suppressing Caribbean reef growth potential
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