1,946 research outputs found

    In The Astronomy Tradition at Augustana

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    Abstract: “In the Astronomy Tradition at Augustana was written as a response to a suggestion made by Dr. Conrad Bergendoff, president emeritus at Augustana College, Rock Island, Illinois. I had prepared a paper for the Contemporary Club of Davenport, Iowa which dealt with the program of the John Deere Planetarium on the campus and its contribution to the Quad-Cities community. Dr. Bergendoff felt that a more inclusive report was needed, and he convinced me that I should write the complete history of the astronomy department. His many creative suggestions have made the story most interesting and I am indebted to him for all his help. My wife has spent numerous hours proofreading the original manuscript and its many revisions. Nancy Johnson, Director of Alumni Relations at Augustana, entered the manuscript in her computer where material could be added or deleted with minimal effort on my part. I am grateful to Dr. Erick Schonstedt, member of the Augustana College Board of Trustees, for his generous financial contribution to help defray the cost of publication. -- Harry E. Nelson” - Front matter Table of Contents: Foreword / Astronomy Professors / Search for Meteorites / Carl Gamble and the Popular Astronomy Club / John Deere Planetarium / Visiting Astronomers / United States Space Program / Eclipse Chasers Club / Recent Acquisitions / Bibliography / Other Historical Society Publications.https://digitalcommons.augustana.edu/ahsbooks/1001/thumbnail.jp

    Twirling of Actin by Myosins II and V Observed via Polarized TIRF in a ModiïŹed Gliding Assay

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    The force generated between actin and myosin acts predominantly along the direction of the actin filament, resulting in relative sliding of the thick and thin filaments in muscle or transport of myosin cargos along actin tracks. Previous studies have also detected lateral forces or torques that are generated between actin and myosin, but the origin and biological role of these sideways forces is not known. Here we adapt an actin gliding filament assay in order to measure the rotation of an actin filament about its axis (“twirling”) as it is translocated by myosin. We quantify the rotation by determining the orientation of sparsely incorporated rhodamine-labeledactin monomers, using polarized total internal reflection (polTIRF) microscopy. In order to determine the handedness of the filament rotation, linear incident polarizations in between the standard s- and p-polarizations were generated, decreasing the ambiguity of our probe orientation measurement four-fold. We found that whole myosin II and myosin V both twirl actin with a relatively long (~ ”m), left-handed pitch that is insensitive to myosin concentration, filament length and filament velocity

    Proceedings, Pot Chrysanthemum School, 1971

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    Space management / Robert W. Langhans -- Soils / D. C. Kiplinger -- Nutrition / George L. Staby -- Temperature and photoperiod / Joseph W. Love -- Automated short day control -- R. A. Aldrich -- Growth regulators / James B. Shanks -- Programming for insect-free pot mums / Richard K. Lindquist -- Programming for disease-free pot mums / Lester P. Nichols and Paul E. Nelson -- Where you go wrong / Harry K. Tayam

    Lipodistrofia congénita generalizada tipo 2 en la cultura Moche

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    The Moche artist are among the most outstanding plastic representatives in the central Andes during the pre-Hispanic era, within this scenario, we could analyze a sculptural ceramic piece (code C-1335) recorded in the Huaca de la Luna archaeological site in Trujillo, PerĂș. The vessel corresponds to two individuals with morphological characteristics that allow them to be associated with type 2 congenital generalized lipodystrophy. Considering the geographical, the physical features, and the current cases of this disease, allow us to indicate that people with generalized congenital lipodystrophy probably existed in Mochica society during pre-Hispanic times.Los artistas moches (50 y 850 años d. C.) son unos de los mayores representantes plĂĄsticos en los andes centrales durante la Ă©poca prehispĂĄnica, dentro de este escenario fue posible el anĂĄlisis de una pieza de cerĂĄmica registrada en el sitio arqueolĂłgico Huaca de la Luna, ubicada en Trujillo. La vasija corresponde a dos individuos con caracterĂ­sticas morfolĂłgicas que permite asociarlos con el padecimiento de lipodistrofia congĂ©nita generalizada tipo 2. Considerando la zona geogrĂĄfica, los rasgos fĂ­sicos y los casos actuales de esta enfermedad nos permite indicar que en la sociedad Mochica probablemente existieron personas con lipodistrofia congĂ©nita generalizada

    Impact of the Deepwater Horizon oil spill on a deep-water coral community in the Gulf of Mexico

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    To assess the potential impact of the Deepwater Horizon oil spill on offshore ecosystems, 11 sites hosting deep-water coral communities were examined 3 to 4 mo after the well was capped. Healthy coral communities were observed at all sites \u3e20 km from the Macondo well, including seven sites previously visited in September 2009, where the corals and communities appeared unchanged. However, at one site 11 km southwest of the Macondo well, coral colonies presented widespread signs of stress, including varying degrees of tissue loss, sclerite enlargement, excessmucous production, bleached commensal ophiuroids, and covering by brown flocculent material (floc). On the basis of these criteria the level of impact to individual colonies was ranked from 0 (least impact) to 4 (greatest impact). Of the 43 corals imaged at that site, 46% exhibited evidence of impact onmore than half of the colony,whereas nearly a quarter of all of the corals showed impact to \u3e90% of the colony. Additionally, 53% of these corals\u27 ophiuroid associates displayed abnormal color and/or attachment posture. Analysis of hopanoid petroleumbiomarkers isolated from the floc provides strong evidence that this material contained oil fromtheMacondowell. The presence of recently damaged and deceased corals beneath the path of a previously documented plume emanating from the Macondo well provides compelling evidence that the oil impacted deep-water ecosystems. Our findings underscore the unprecedented nature of the spill in terms of its magnitude, release at depth, and impact to deep-water ecosystems

    Comparative chromosome painting discloses homologous Segments in distantly related mammals

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    Comparative chromosome painting, termed ZOO-FISH, using DNA libraries from flow sorted human chromosomes 1,16,17 and X, and mouse chromosome 11 discloses the presence of syntenic groups in distantly related mammalian Orders ranging from primates (Homo sapiens), rodents (Mus musculus), even-toed ungulates (Muntiacus muntjak vaginalis and Muntiacus reevesi) and whales (Balaenoptera physalus). These mammalian Orders have evolved separately for 55-80 million years (Myr). We conclude that ZOO-FISH can be used to generate comparative chromosome maps of a large number of mammalian species

    Twirling of actin by myosins II and V observed via polarized TIRF in a modified gliding assay

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    The force generated between actin and myosin acts predominantly along the direction of the actin filament, resulting in relative sliding of the thick and thin filaments in muscle or transport of myosin cargos along actin tracks. Previous studies have also detected lateral forces or torques that are generated between actin and myosin, but the origin and biological role of these sideways forces is not known. Here we adapt an actin gliding filament assay in order to measure the rotation of an actin filament about its axis (twirling) as it is translocated by myosin. We quantify the rotation by determining the orientation of sparsely incorporated rhodamine-labeled actin monomers, using polarized total internal reflection (polTIRF) microscopy. In order to determine the handedness of the filament rotation, linear incident polarizations in between the standard s- and p-polarizations were generated, decreasing the ambiguity of our probe orientation measurement four-fold. We found that whole myosin II and myosin V both twirl actin with a relatively long (micron), left-handed pitch that is insensitive to myosin concentration, filament length and filament velocity
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