1,805 research outputs found
Robert C. Drews, Miles C. Whitener, and August W. Geise Oral History
No full textRobert C. Drews, Miles C. Whitener, and August W. Geise were interviewed by Paul G. Anderson on May 8, 1980 for approximately 63 minutes.https://digitalcommons.wustl.edu/oralhistories/1099/thumbnail.jp
Aleuroglandulus striatus Sampson & Drews 1941
No full textAleuroglandulus striatus Sampson & Drews (Figs 28, 88) Aleuroglandulus striatus Sampson & Drews, 1941: 157–159. Syntypes, Mexico. DISTRIBUTION. Neotropical Region: Belize, Costa Rica, Guatemala, Honduras, Mexico. COMMENTS. See key to species, above, for distinguishing characters. The author has only encountered A. striatus in very small numbers, usually widely scattered. Even with dorsal glandular areas inevident, this species exhibits all other generic characters.Published as part of Martin, Jon H., 2005, Whiteflies of Belize (Hemiptera: Aleyrodidae) Part 2 - a review of the subfamily Aleyrodinae Westwood, pp. 1-116 in Zootaxa 1098 (1) on page 15, DOI: 10.11646/zootaxa.1098.1.1, http://zenodo.org/record/505154
Konstruierte Normalitäten - normale Abweichungen
No full textDer Sammelband vereint Beiträge der Tagung „Konstruierte Norm[alität][en] – normale Abweichung[en]“, die vom Konstanzer Netzwerk internationaler (Post-)Doktorandinnen organisiert wurde. Prozesse der Normbildungen und der Grenzziehung zwischen Normalitäten und Abweichungen werden in vier interdisziplinären Sektionen diskutiert. Die AutorInnen thematisieren normative Relationalität und Abhängigkeit von Kontexten wie Ort, Zeit, Raum, Kultur, Geschlecht oder Tradition sowie den Verlust ihrer Orientierungsfunktion in zunehmend pluralistischen Gesellschaften. Sie zeigen, wie die starke Individualisierung von Normen und Normalitäten zur Vervielfältigung der Abweichungen führt, die in neuen Normbildungsprozessen und der Konstruktion neuer Normalitäten münden und diese zugleich hinterfragen. Das Buch wendet sich an Dozierende und Studierende der Literaturwissenschaften, Linguistik, Gender Studies, Medienwissenschaften, Soziologie, Kulturwissenschaften, BWL, Psychologie sowie an LehrerInnen in Schul- und Erwachsenenbildung, SozialarbeiterInnen, Migrations- und Integrationsbeauftragte.
Il volume, che raccoglie contributi del convegno interdisciplinare „Konstruierte Norm[alität][en] – normale Abweichung[en], tenutosi all’Università di Konstanz, riflette sui processi dinamici che presiedono alla formazione dei concetti di “norma” e “normalità ”e al complesso rapporto tra la norma/normalità e le sue deviazioni in ambito sociale, culturale, letterario, linguistico ed economico. Gli autori e le autrici mettono in luce la stretta dipendenza delle norme dal contesto (storico, geografico, culturale, linguistico) e la progressiva perdita della loro funzione di orientamento nella società pluralista e dimostrano come non solo la sociologia e l’economia ma anche nella letteratura e nella linguistica la definizione delle norme porti a una proliferazione delle deviazioni dalle stesse, nonché a processi che tendono a formarne di nuove e alternative. Il volume si rivolge a docenti e studenti di letteratura, linguistica, Gender Studies, arti visive, sociologia, psicologica, economia e a insegnanti di scuola, assistenti sociali e mediatori culturali
Acknowledgements for Brush's article "Persistent Generation of Heat in Some Rocks and Minerals; and Its Probable Significance" (1927 paper), 1928
No full textTyped letter from Mildred G. Drews to Charles F., Sr., thanking Brush on behalf of Joel B. Hayden for sending a copy of the paper, Persistent Generation of Heat in Some Rocks by Brush, to HaydenCharles F. Brush, Sr., PapersSeries 1: CorrespondenceSubseries 2: Acknowledgments (1921-1929)Box 3Folder
Arthur Drews, Die Leugnung der Geschichtlichkeit Jesu in Vergangenheit und Gegenwart (Wissen und Wirken, 33), Karlsruhe (G. Braun), 1925
No full textAlfaric Prosper. Arthur Drews, Die Leugnung der Geschichtlichkeit Jesu in Vergangenheit und Gegenwart (Wissen und Wirken, 33), Karlsruhe (G. Braun), 1925. In: Revue d'histoire et de philosophie religieuses, 6e année n°6, Novembre-décembre 1926. pp. 589-590
J. Willard Marriott Library Information Visualization Lecture Series presents Dr. Kirsten R. Butcher... Dr. Frank A. Drews, ... James Agutter, ... Dr. Ben Fry
No full textPoster publicizing the "Information Visualization Lecture Series" held during Winter Semester of 2013 in the Gould Auditorium of the J. Willard Marriott Library. Presenters included Dr. Kirsten R. Butcher (Educational Psychology), Dr. Frank A. Drews (Cognitive Psychology); James Agutter (College of Architecture and Planning); and Dr. Ben Fry (author of "Visualizing Data.
Petrarca spricht Deutsch? Aneignung, Transformation, Metamorphose der Fremde ins Eigene
No full textIm Beitrag werden einige der Wege rekonstruiert, die in der deutschsprachigen Literatur zur Entstehung eines interkulturellen Dialogs zwischen dem Eigenen und dem Fremden und zu einer graduellen und progressiven Integration des Fremden im Eigenen f hrten. Insbesondere wird durch die Bestimmung von einigen Etappen in der Begegnung der italienischen mit der deutschen Kultur diskutiert, wie sich die deutsche Literatur in Fortf hrung und Transformation fremder Kulturen bildete: Sie stiftete ihre Normalit t zuerst durch Aneignung ( bersetzungen), sp ter durch Verwandlung und progressive Verinnerlichung (Nachdichtungen von fremden Mustern) und in j ngerer Zeit durch die radikale Transformation und Manipulation des Fremden im Eigenen. Daraus entsteht ein internationales, kosmopolitisches Bild der deutschen Dichtung, die als ein Treffpunkt von fremden Kulturen ihre Identit t aus der Dialektik zwischen dem Eigenen und dem Fremden entwickelte und durch den Austausch mit dem Fremden ihre Originalit t bzw. Normalit t entdeckte. Leitfaden des Beitrags ist die Figur und die vielf ltige Rezeption von Petrarcas Dichtung auf deutschsprachigem Boden
Die Dynamik magnetischer Vortices und Antivortices
No full textThe dynamics of magnetic vortices and antivortices in ferromagnetic thin-film elements
is investigated by numerical simulations and analytical calculations. For the numerical
calculations the Landau-Lifshitz-Gilbert equation is solved by the Object Oriented Micromagnetic
Framework (OOMMF). For the analytical calculations a two-dimensional
oscillator model is used. The response of vortices and antivortices to external fields and
spin-polarized currents is studied for increasing amplitudes of the exciting alternating
magnetic fields and currents, which result in vortex motions in the linear, non-linear, and
in the highly non-linear regime of vortex creation.
In the linear regime vortex dynamics is described by a harmonic oscillator model.
Micromagnetic simulations yield the eigenfrequency and the damping of gyration in dependence
on the size of the sample. The oscillator model is compared to the simulations.
The elliptical shape of the trajectories and the phase between gyration and alternating
excitation show good accordance. Resonance curves illustrate the dependence of the
semiaxes and the phase on the exciting frequency. The harmonic oscillator model can
be extended to a nonlinear oscillator model. The nonlinear equation of motion is solved
by a Runge-Kutta-method. A comparison of the trajectories from this model with the
trajectories from micromagnetic simulations yields the strength of the nonlinearities in
dependence on the size of the sample. The limit between nonlinear gyration and the
onset of the creation of vortices is estimated by a characteristic velocity of the vortex.
In the highly non-linear regime of core gyration micromagnetic simulations reach their
limits due to the formation of a magnetic singularity, the so-called Bloch point, where
the polarization of the vortex core switches. A general description is used to explain the
occurance of intermediate states at vortex formation.
Finally a possible application of vortices in memory cells is illustrated using the insights
from the investigations of the linear and the highly non-linear regime. The write
and the read process in the vortex random access memory (VRAM) or antivortex random
access memory (AVRAM) are implemented by vortex core switching and gyration.In dieser Arbeit wird die Bewegung magnetischer Vortices und Antivortices in ferromagnetischen
dünnen Schichten mit Hilfe von numerischen Simulationen und analytischen
Rechnungen untersucht. Das verwendete mikromagnetische Simulationsprogramm Object
Oriented Micromagnetic Framework (OOMMF) löst die Landau-Lifshitz-Gilbert
Gleichung numerisch. Die analytischen Rechnungen werden mit einem zweidimensionalen
Oszillatormodell durchgeführt. Dabei wird das dynamische Ansprechverhalten von
Vortices und Antivortices auf externe Felder und spinpolarsierte Ströme betrachtet. Eine
Anregung mit steigender Amplitude bewirkt eine Bewegung im linearen, nicht linearen
und hochgradig nichtlinearen Bereich der Vortexentstehung.
Im linearen Bereich wird die Vortexbewegung mit einem harmonischen Oszillatormodell
beschrieben. Mikromagnetische Simulationen ergeben die Eigenfrequenz und die
Dämpfung der Gyration in Abhängigkeit von der Probengröße. Das Oszillatormodell und
die Simulationen werden miteinander verglichen. Die elliptische Form der Trajektorien
und die Phase zwischen Gyration und alternierender Anregung zeigen gute Übereinstimmung.
Resonanzkurven stellen die Abhängigkeit der Halbachsen und der Phase
von der Anregungsfrequenz dar. Das harmonische Oszillatormodell läßt sich auf ein
nichtlineares Oszillatormodell erweitern. Die nichtlineare Bewegungsgleichung wird mit
einem Runge-Kutta Verfahren gelöst. Ein Vergleich der Trajektorien des nichtlinearen
Oszillatormodells mit den Trajektorieren der mikromagnetischen Simulationen ergibt
die Stärke der Nichtlinearitäten in Abhängigkeit von der Probengröße. Die Grenze
zwischen nichtlinearer Gyration und Vortexentstehung wird durch eine charakteristische
Vortexgeschwindigkeit bestimmt. Im hochgradig nichtlinearen Bereich erreicht das
mikromagnetische Modell seine Grenzen aufgrund der Entstehung einer magnetischen
Singularität, des Bloch-Punkts, bei dem die Polarization des Vortexkerns umschaltet. Ein
allgemeiner Formalismus beschreibt die Ursache für die Bildung der Zwischenzustände
beim Vortexschalten.
Abschließend wird eine mögliche Anwendung von Vortices in Speicherzellen präsentiert.
Dabei werden die Erkenntnisse über die Vortexdynamik aus den vorherigen
Kapiteln benutzt. Der Schreib- und Leseprozess sind in dem Vortex Random Access
Memory (VRAM) oder dem Antivortex Random Access Memory (AVRAM) über das
Vortexschalten und die Vortexgyration realisiert
Aleuropleurocelus Drews & Sampson
No full text<i>ALEUROPLEUROCELUS</i> Drews & Sampson <p> <i>Aleuropleurocelus</i> Drews & Sampson, 1956: 282. Type species <i>Aleuropleurocelus laingi</i> by original designation.</p> <p> DIAGNOSIS AND COMMENTS. As interpreted here, <i>Aleuropleurocelus</i> comprises species with the following combination of characters: venter smaller than dorsum, resulting in deflexion of dorsum (Fig 133–134), with morphological margin being ventrally located and usually crenulate [this character is also seen in species of <i>Aleurovitreus</i> <b>gen. nov.</b>, figures 22–23, <i>q.v.</i>]; puparia black; vasiform orifice slightly elevated (sometimes appears to be surrounded by a sclerotised ring) and variously shaped, but smooth internally and fully occupied by operculum; lingula concealed by operculum; transverse moulting sutures usually reach beyond apparent margin, onto deflexed part of morphological dorsum; cephalic setae present or absent, but first abdominal setae always absent.</p> <p> Drews & Sampson (1956, 1958) considered that their new genus, <i>Aleuropleurocelus</i>, should accommodate New World species which have black puparia with the dorsal surface deflexed to meet a smaller venter. They stated that this genus differed from the Old World genus <i>Tetralicia</i> Harrison (1917) through the latter having its true (ventrally located) margin smooth or irregular, its operculum not fully occupying the vasiform orifice and the vasiform orifice being toothed internally. However, <i>Tetralicia</i> then only included the type species, <i>T. ericae</i> Harrison and, as more species have become available for study in both hemispheres, this suite of separation characters has become unreliable. However, Old and New World assemblages of whitefly species have often proved to be generically separate (see comments on <i>Aleurocybotus</i>, p. 10), and therefore <i>Aleuropleurocelus</i> and <i>Tetralicia</i> are both retained pending further clarification of their respective diagnostic characters.</p> <p> Puparia of <i>Aleurotrachelus cecropiae</i> Bondar (1923) in BMNH, (probably syntypes, see Martin, 2004:56), have their morphological margin substantially deflexed and are characteristically tiny, and the opportunity is therefore taken here to transfer this species to <i>Aleuropleurocelus</i> (<b>comb. nov.</b>).</p> <p> Slides of <i>Aleurodes abnormis</i> Quaintance (1900) in BMNH (ex­USNM) had been labelled as “ <i>Tetralicia</i> ” <i>abnormis</i>, but Quaintance & Baker (1914) had transferred this species to <i>Tetraleurodes.</i> As far as the author is aware, the combination <i>Tetralicia abnormis</i> has never been published. However, examination of these puparia reveals the morphological true margin to be significantly deflexed, and this species is here transferred to <i>Aleuropleurocelus</i> <b>comb. nov.</b>. The uncertain relationship between <i>Aleuropleurocelus</i> and <i>Tetralicia</i> is discussed two paragraphs above.</p> <p> There are presently ten described species included in <i>Aleuropleurocelus</i> but, in Belize, ten undescribed species are considered to belong to this genus (see Appendix 1). Each of the Belize <i>Aleuropleurocelus</i> species is represented only by a small numbers of specimens, and none warrants description here, although two are illustrated to show generic characters (Figs 133–134).</p>Published as part of <i>Martin, Jon H., 2005, Whiteflies of Belize (Hemiptera: Aleyrodidae) Part 2 - a review of the subfamily Aleyrodinae Westwood, pp. 1-116 in Zootaxa 1098 (1)</i> on pages 19-20, DOI: 10.11646/zootaxa.1098.1.1, <a href="http://zenodo.org/record/5051548">http://zenodo.org/record/5051548</a>
In situ hydrocarbon concentrations from pressurized cores in surface sediments, northern Gulf of Mexico
No full textTwo newly developed coring devices, the Multi-Autoclave-Corer and the Dynamic Autoclave Piston Corer were deployed in shallow gas hydrate-bearing sediments in the northern Gulf of Mexico during research cruise SO174 (Oct–Nov 2003). For the first time, they enable the retrieval of near-surface sediment cores under ambient pressure. This enables the determination of in situ methane concentrations and amounts of gas hydrate in sediment depths where bottom water temperature and pressure changes most strongly influence gas/hydrate relationships. At seep sites of GC185 (Bush Hill) and the newly discovered sites at GC415, we determined the volume of low-weight hydrocarbons (C1 through C5) from nine pressurized cores via controlled degassing. The resulting in situ methane concentrations vary by two orders of magnitudes between 0.031 and 0.985 mol kg? 1 pore water below the zone of sulfate depletion. This includes dissolved, free, and hydrate-bound CH4. Combined with results from conventional cores, this establishes a variability of methane concentrations in close proximity to seep sites of five orders of magnitude. In total four out of nine pressure cores had CH4 concentrations above equilibrium with gas hydrates. Two of them contain gas hydrate volumes of 15% (GC185) and 18% (GC415) of pore space. The measurements prove that the highest methane concentrations are not necessarily related to the highest advection rates. Brine advection inhibits gas hydrate stability a few centimeters below the sediment surface at the depth of anaerobic oxidation of methane and thus inhibits the storage of enhanced methane volumes. Here, computerized tomography (CT) of the pressure cores detected small amounts of free gas. This finding has major implications for methane distribution, possible consumption, and escape into the bottom water in fluid flow systems related to halokinesis
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