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Sample records for quantitative bestimmung von

  1. Quantitation of canine plasma von Willebrand factor antigen using a commercial enzyme-linked immunosorbent assay.

    PubMed

    Johnstone, I B; Crane, S

    1991-01-01

    The purpose of this study was to evaluate a commercial enzyme-linked immunosorbent assay (ELISA) for human von Willebrand factor antigen (vWF:Ag) with respect to its potential value in quantitating the protein in canine plasma. The assay was a sandwich technique using F(ab')2 fragments specific for von Willebrand factor (vWF) and a peroxidase conjugated rabbit anti-vWF second antibody, with a microplate as the support surface. Canine plasmas were assayed by ELISA, and by Laurell electroimmunoassay (EIA), our reference methodology. The ELISA had a within-day variation of 1.21-4.44% and a between-day variation of 0.85-4.88% depending on the level of vWF:Ag. The sensitivity of the assay was less than 0.1% vWF:Ag. The range of vWF:Ag concentrations in plasmas from 24 clinically normal dogs compared favorably with the range for the same plasmas when assayed by EIA (ELISA = 60-152% of normal; EIA = 50-142% of normal). In 121 canine plasmas with vWF:Ag concentrations (as assessed by EIA) ranging from undetectable levels (less than 6% of normal) to 142% of normal, there was good correlation with measurements made by ELISA (correlation coefficient = 0.835). It was concluded that this commercial ELISA technique could be used to provide reliable, same-day measurements of canine plasma vWF:Ag. Since it requires no special equipment other than a microplate reader and washer it is particularly suitable for laboratories lacking the electrophoretic expertise or equipment required for EIA. PMID:1884278

  2. Reaktive Tracer zur Bestimmung der sedimentären Aquifer-Oxidationskapazität im Labor- und Feldversuch

    NASA Astrophysics Data System (ADS)

    Dethlefsen, Frank; Bliss, Fabian; Wachter, Thorsten; Dahmke, Andreas

    Kurzfassung Mikrobiell reduzierbares Eisen(III) im Aquifer kann als Elektronenakzeptor von großer Bedeutung für Natural Attenuation (NA) von aromatischen Kohlenwasserstoffen sein und bildet den Hauptbestandteil der sedimentären Oxidationskapazität (OXC) des Aquifers. Untersuchungsgegenstand war der Vergleich traditioneller, nasschemischer Methoden mit neuentwickelten, reaktiven Tracerverfahren zur Bestimmung der sedimentären OXC. Die innovativen Tracermethoden haben gegenüber nasschemischen Extraktionsverfahren den prinzipiellen Vorteil, dass sie einen integralen Ansatz zur Bestimmung der sedimentären OXC bilden, weil geochemische und hydraulische Heterogenitäten des Aquifers berücksichtigt werden. Daher wurden am RETZINA-Standort Zeitz einerseits herkömmliche Säure-Extraktionsmethoden (bestimmter Eisen(III)-Gehalt: 0,43 +/- 0,07 mg/g Aquifermaterial) und andererseits reaktive Tracertests mit Phosphat-(Eisen(III): 1,0 mg/g) und Sulfidtracern (Eisen(III): 0,31 +/- 0,02 mg/g) in Laborversuchen sowie Bioabbauversuche mit Toluol als Kohlenstoffquelle undGeobacter metallireducensals Eisen(III)-Reduzierer (Eisen(III): 1,0 mg/g) durchgeführt. Sulfid als reaktiver Tracer wurde in Form eines ?Push-Pull-Tests`` im Feldversuch eingesetzt (Eisen(III): 1,1 mg/g). Zudem bedeutet die Anwendung des Feld-Tracerverfahrens deutlich weniger Zeitaufwand in der Durchführung als die Anwendung traditioneller Extraktionsmethoden. Microbially reducible iron(III) is important as a terminal electron acceptor for the Natural Attenuation (NA) of aromatic hydrocarbons and forms the balance of the aquifer's sedimentary oxidation capacity (OXC). It was the aim of this investigation to compare traditional acid extraction methods to reactive tracer methods in quantifying the sedimentary OXC. The sedimentary OXC at the RETZINA test site in Zeitz was therefore determined through traditional acid extraction methods (determined Iron(III)-content: 0.43 +/- 0.07 mg/g aquifer material) and through reactive tracer tests with phosphate (iron(III): 1.0 mg/g) and sulphide (iron(III): 0.31 +/- 0.02 mg/g) in lab experiments. In the latter biodegradation experiments were conducted with toluene as the carbon source andGeobacter metallireducensas the iron(III) reducing bacterium (iron(III): 1.0 mg/g). A field tracer experiment designed as a push-pull-test was performed using the sulphide tracer (iron(III): 1.1 mg/g). The principal advantage of innovative tracer methods compared to wet chemical extraction methods is that they offer an integral approach for the determination of the sedimentary OXC, since geochemical and hydraulic heterogeneities are considered. Furthermore, they require less time than traditional extraction methods.

  3. Computer based quantitative analysis of capillary abnormalities in systemic sclerosis and its relation to plasma concentration of von Willebrand factor.

    PubMed Central

    Scheja, A; Akesson, A; Niewierowicz, I; Wallin, L; Wildt, M; Wollheim, F A

    1996-01-01

    OBJECTIVES--To evaluate an objective and quantitative method for assessment of capillary abnormalities in systemic sclerosis (SSc). METHODS--Nailfold capillaries were investigated by capillary microscopy and photographed in 17 consecutive SSc patients (five with diffuse cutaneous systemic sclerosis (dSSc) and 12 with limited cutaneous systemic sclerosis (lSSc)) and in 17 healthy controls. Investigators having no access to clinical data made drawings from magnified projections of coded photographs and analysed them using a computer program. Capillary density (capillary loops/mm in the distal row) and median capillary loop area were calculated. Presence of functional or organic arterial changes was evaluated by measurement of finger pressure with finger cooling. Plasma concentration of von Willebrand factor (VWF) was analysed using an enzyme linked immunosorbent assay (ELISA). RESULTS--In 16 of 17 SSc patients and 13 of 17 controls the technical quality of the photographs was sufficient for computer analysis. Capillary density was decreased in dSSc (median 6.9 loops/mm) and in lSSc (median 3.8 loops/mm) compared with healthy controls (8.9 loops/mm) and median capillary loop area was increased in dSSc (7.3 x 10(-3) mm2) and in lSSc (8.5 x 10(-3) mm2) compared with healthy controls (5.0 x 10(-3) mm2). An inverse relation was found between capillary density and median capillary loop area in SSc patients. Plasma VWF was increased in patients (median 401 IE/l in dSSc and 409 IE/l in lSSc) compared with controls matched for age and sex (median 276 IE/l). Computer based analysis showed capillary density below the control range and median capillary loop area above the control range in 14 of 16 SSc patients. Measurement of finger pressure with finger cooling showed organic vascular changes in nine of 13 SSc patients. CONCLUSION--Computer based quantitative analysis has low interobserver variability and is a quantitative and sensitive method of assessing capillary abnormalities in SSc. Images PMID:8572735

  4. Die Bestimmung der Herkunft der Marmore von Büsten der Münchener Residenz

    NASA Astrophysics Data System (ADS)

    Riederer, Josef; Hoefs, Joachim

    1980-09-01

    51 Greek, Roman and Renaissance marble busts from the Antiquarium of the Residenz in Munich were studied for their C- and O-isotopic composition. Apart from some overlapping values, this technique permits — contrary to microscopic and chemical methods — localization of different Turkish, Greek and Italian marble deposits.

  5. Bestimmung des Verteilungskoeffizienten von Si in Fe mit Hilfe Spektroskopischer Methoden

    NASA Astrophysics Data System (ADS)

    Ebenberger, Helga; Wernisch, Johann

    Spectroscopical methods have been used to determine the effective distribution coefficient of silicon within Fe-3% Si crystals, grown from Trafoperm N3 using the Bridgman method. A remarkable coincidence has been found between the values of the effective distribution coefficient determined by the method of atomic absorption spectrometry (AAS) and those determined with an electron probe microanalyser (EPMA). The investigations on single crystals, bicrystals and coarse-grained polycrystals show a strong dependence of the effective distribution coefficient k on the orientation as well as a big influence of enviromental conditions on crystal growth. Moreover, the analysis of the bicrystals prove a clear dependence of the effective distribution coefficient of one part of the bicrystal not only on its own crystallographic orientation but also on that of the other part.

  6. Einfluss von Heterogenität und Messfehler auf die Bestimmung von Abbauraten erster Ordnung eine Virtueller-Aquifer-Szenarioanalyse

    NASA Astrophysics Data System (ADS)

    Bauer, S.; Beyer, C.; Kolditz, O.

    2007-03-01

    The principal idea of the Virtual Aquifer is to simulate and evaluate monitoring strategies and remediation options for contaminated sites by modelling typical contamination scenarios. Here the determination of first order degradation rates is studied. A virtual reality is generated by simulating the spreading of a plume, originating from a defined source and subject to first order degradation. This plume is investigated using monitoring wells placed along the plume center line. From the information thus obtained, first order degradation rates are calculated by typically used methods and are then compared to the predefined value. This comparison is conducted for different degrees of heterogeneity. It is found that with increasing heterogeneity, the calculated degradation rates can overestimate the real degradation rate by several orders of magnitude and show a high uncertainty. Measurement errors are then introduced for piezometric head and concentration measurements. It is found that up to several orders of magnitude deviations can occur between the estimated first order rate constant and the true rate, with errors of the piezometric head measurement causing the dominant uncertainty.

  7. Neue biosensorische Prinzipien für die Hämoglobin-A1c Bestimmung

    NASA Astrophysics Data System (ADS)

    Stöllner, Daniela

    2002-06-01

    Hämoglobin-A1c (HbA1c) ist ein Hämoglobin (Hb)-Subtypus, der durch nicht-enzymatische Glykierung des N-terminalen Valinrestes der Hämoglobin-beta-Kette entsteht. Das gemessene Verhältnis von HbA1c zum Gesamt-Hämoglobin (5-20 % bei Diabetikern) repräsentiert den Mittelwert der Blutglucosekonzentration über einen zweimonatigen Zeitraum und stellt zur Beurteilung der diabetischen Stoffwechsellage eine Ergänzung zur Akutkontrolle der Glukosekonzentration dar. Ziel der vorliegenden Arbeit war es, einen amperometrischen Biosensor für die Bestimmung des medizinisch relevanten Parameters HbA1c zu entwickeln. Durch Selektion geeigneter Bioerkennungselemente und deren Immobilisierung unter Erhalt der Bindungsfunktion für die Zielmoleküle Hämoglobin bzw. HbA1c wurden spezifische, hochaffine und regenerationsstabile Sensoroberflächen geschaffen. Für die Entwicklung des HbA1c-Biosensors wurden zwei Konzepte - Enzymsensor und Immunosensor - miteinander verglichen. Die enzymatische Umsetzung von HbA1c erfolgte mit der Fructosylamin Oxidase (FAO) aus Pichia pastoris N 1-1 unter Freisetzung von H2O2, welches sowohl optisch über eine Indikatorreaktion als auch elektrochemisch nach Einschluss der FAO in PVA-SbQ und Fixierung des Immobilisats vor einer H2O2-Elektrode nachgewiesen wurde. Die Kalibration des Enzymsensors mit der HbA1c-Modellsubstanz Fructosyl-Valin ergab Nachweisgrenzen, die ausserhalb des physiologisch relevanten HbA1c-Konzentrationsbereich lagen. Aus der Umsetzung von glykierten Peptiden mit einer nicht HbA1c analogen Aminosäurensequenz, z.B. Fructosyl-Valin-Glycin wurde zudem eine geringe HbA1c-Spezifität abgeleitet. Für den Immunosensor wurden zwei heterogene Immunoassay-Formate unter Verwendung von hochaffinen und spezifischen Antikörpern in Kombination mit Glucose Oxidase (GOD) als Markerenzym zum Nachweis von HbA1c untersucht. Beim indirekt-kompetitiven Immunoassay wurde anstelle des kompletten HbA1c-Moleküls das glykierte Pentapeptid Fructosyl-Valin-Histidin-Leucin-Threonin-Prolin (glkPP) als Kompetitor und Affinitätsligand immobilisiert und so eine regenerierfähige Oberfläche geschaffen. Beim Sandwich-Immunoassay wurde im ersten Schritt Gesamt-Hämoglobin an die mit Haptoglobin (Hp) modifizierte Festphase angereichert und im zweiten Schritt der gebundene HbA1c-Anteil nachgewiesen. Für die Konstruktion des HbA1c-Immunosensors wurden Affinitätsmatrizen durch Modifizierung von Cellulose-Dialysemembranen mit glkPP bzw. Hp hergestellt. Grundlegend studiert wurde die Aktivierung der Cellulose-Membranen mit 1,1'-Carbonyldiimidazol (CDI) und 1-Cyano-4-dimethylaminopyridintetrafluoroborat (CDAP) als Aktivierungsagenzien. Eine gerichtete Immobilisierung der Liganden wurde realisiert, indem glkPP über dessen C-Terminus (einzige Carboxylatgruppe) und Hp über dessen periodat-oxidiertem Kohlenhydratrest an die amino- oder hydrazidfunktionalisierte Membranen kovalent gekoppelt wurden. Mit dem Einsatz der glkPP- und Hp-modifizierten Membranen in der elektrochemischen Messzelle war erstmalig der biosensorische Nachweis von HbA1c möglich. Als Transduktor diente eine Pt-Elektrode, an der das von der GOD generierte H2O2 umgesetzt und ein mit der HbA1c-Konzentration korrelierendes Stromsignal erzeugt wurde. Die Immunosensoren zeigten Ansprechzeiten von 3 s. Mit dem Immunosensor auf Basis des indirekt-kompetitiven Testprinzips wurde eine Kalibrationskurve für HbA1c im Bereich von 0,25-30 µg/ml (3,9-465 nM, CV 3-9 %) mit Assayzeiten von 60 min und mit dem Immunosensor im Sandwich-Format eine Kalibrationskurve im Bereich von 0,5-5 µg/ml (7,8-78 nM; 5-50 % HbA1c vom Gesamt-Hb, CV 6-10 %, 3 h) aufgenommen. Hemoglobin-A1c (HbA1c) is a hemoglobin subtype formed by non-enzymatic reaction of glucose with the N-terminus of the beta-polypeptide chains. As it reflects the glycemic status of diabetics over the preceding 8-12 weeks, the determination of HbA1c has become an established procedure in the management of diabetes mellitus. It is measured as the percentage of total hemoglobin. Up to 5 % HbA1c are considered as normal whereas in diabetic subjects it could be elevated from 5-20 %. In addition to amperometric biosensors for glucose self monitoring which have been successfully applied in diabetes management, biosensors for HbA1c would be an useful supplement for a comprehensive diabetes control. Objective of this work was to develop and compare amperometric biosensors for determination of HbA1c based on enzymatic and immunochemical methods. For the enzyme based HbA1c assay a novel fructosamine oxidase (FAO) derived from marine yeast Pichia pastoris, strain N1-1 was utilized. It recognizes and oxidatively degrades fructosyl-valine (FV) which corresponds to the glycated N-terminus of the beta-chain of HbA1c and therefore is regarded as a model compound for HbA1c. Hydrogen peroxide which is liberated by the FAO during FV conversion was indicated optically in a horseradish peroxidase (POD) coupled reaction and electrochemically. For the biosensor the FAO was embedded in polyvinyl alcohol-stylbazole (PVA-SbQ) and fixed it in front of a Pt-electrode. So far, the measuring range of FV did not cover the clinically relevant range of HbA1c. Low specificity was assumed since enzyme activity also was obtained with glycated peptides, e.g. fructosyl-valine-glycine, not corresponding to the glycated N-terminus of the hemoglobin-beta-chain. For the immunosensor two immunoassays formats - heterogeneous sandwich and heterogeneous competitive - were tested. The assays were designed as follows: The competitive immunoassay was based on the immobilized synthetic glycated pentapeptide fructosyl-valine-histidine-leucine-threonine-proline (glkPP) utilized as HbA1c analogue. The peptide has an amino acid sequence corresponding to the N-terminus of the hemoglobin beta-chains and is capable for competition together with the HbA1c of the sample for the amount of a glucose oxidase (GOD)-labelled anti-HbA1c antibody. In the sandwich-type assay haptoglobin (Hp), a natural hemoglobin binding molecule with antibody characteristic properties, was used as bioreceptor for enrichment of total hemoglobin onto the surface. In a subsequent step the HbA1c fraction was quantified by a GOD-labelled HbA1c specific antibody. Cellulose dialysis membrane was used as the solid support for immobilization of Hp and glkPP near the sensor surface. For activation of the membrane two reagents, 1,1‧-carbonyldiimidazole (CDI) and 1-cyano-4-dimethylamino pyridinium tetrafluoroborate (CDAP), were compared with respect to the degree of activation and coupling efficiency. Site-directed immobilization of Hp and glkPP was achieved by coupling Hp via its carbohydrate residue and glkPP via its C-terminus to the activated membrane using a bis-amine or bis-hydrazide spacer. The affinity membranes were placed in front of a modified Clark-type hydrogen peroxide electrode in an electrochemical measuring cell and HbA1c analysis was carried out within the stirred cell. Detection of the bound GOD-label was achieved by measurement of the electrocatalytic oxidation of hydrogen peroxide at +600 mV vs. Ag/AgCl. The indication was done in only 3 s. For the competitive principle a typical inhibition curve with a linear range between 0,25-30 µg/ml (3,9-465 nM, CV 3-9 %, 60 min per sample) HbA1c was obtained. Due to the high functional stability of the peptide multiple regeneration of the affinity surface was possible without loss of binding capacity. With the sandwich assay configuration the clinically relevant range could easily be covered (calibration curve: 5-50 % HbA1c corresponding to 7,8-78 nM, CV 6-10 %, 3 h per sample).

  8. Quantitative Analyse von Korallengemeinschaften des Sanganeb-Atolls (mittleres Rotes Meer). I. Die Besiedlungsstruktur hydrodynamisch unterschiedlich exponierter Außen- und Innenriffe

    NASA Astrophysics Data System (ADS)

    Mergner, H.; Schuhmacher, H.

    1985-12-01

    The Sanganeb-Atoll off Port Sudan is an elongate annular reef which rests on a probably raised block in the fracture zone along the Red Sea-graben. Its gross morphology was most likely formed by subaerial erosion during low sealevel conditions. Features of its topography and hydrography are described. The prevailing wind waves are from NE, Hence, the outer and inner reef slopes are exposed to different hydrodynamic conditions. The sessile benthos was analysed using the quadrat method. Four test quadrats (5×5 m each) were selected on the outer and inner slopes at a depth of 10 m along a SSW-NNE transect across the atoll. Cnidaria were by far the most dominating group; coralline algae, Porifera, Bryozoa and Ascidia, however, counted for just under 3 % living cover. Light and temperature intensities did not differ significantly at the sites studied; water movement, however, decreased in the following order: TQ IV (outer NE side of the reef ring) was exposed to strong swell and surf; TQ II (inner side of the SW-ring) was met by a strong longreef current; TQ I was situated on the outer lee of the SW-atoll ring and TQ III in the inner lee of the NE-side. This hydrodynamic gradient correlates with the composition of the coral communities from predominantly branching Scleractinia (staghorn-like and other Acropora species and Pocillopora) in TQ IV, through a Lobophyllia, Porites and Xenia-dominated community in TQ II, and a mixed community with an increasing percentage of xeniid and alcyoniid soft corals in TQ I, to a community in TQ III which is dominated by the soft corals Sinularia and Dendronephthya. The cnidarian cover ranged between 42.4 and 56.6 % whereby the two exposed test quadrats had a higher living coverage than the protected ones. In total, 2649 colonies comprising 124 species of stony, soft and hydrocorals were recorded by an elaborate method of accurate in-situ mapping. The 90 scleractinian species found include 3 species new to the Red Sea and 11 hitherto unknown species from its central part. Only 7 cnidarian species covered large areas, forming a Xenia macrospiculata-zone in TQ I, a Lobophyllia corymbosa-zone in TQ II, a Sinularia-Dendronephthya-zone in TQ III and an Acropora-Pocillopora verrucosa-zone in TQ IV. Hydrodynamic exposition and ratio of genus abundance Acropora: Montipora are closely correlated: on the windward side (TQ IV) it is 943:4, but on the leeward side (TQ I) 18:208. Apart from the taxonomic and quantitative distribution of species and colonies, types of growth form and categories of the dead substrate are given. Since soft corals do not contribute to the reef framework, the distribution of Scleractinia and Alcyonaria indicates that at Sanganeb-Atoll reef substance is mainly generated on the windward side.

  9. Theodore von Karman

    NASA Technical Reports Server (NTRS)

    1926-01-01

    Theodore von Karman. NACA: In the eyes of most aeronautical experts, the overall record of Max Munk in aerodynamic research falls short of that achieved by fellow immigrant Theodore von Karman (the short man in the double breasted coat in the middle), shown here visiting Langley in December 1926. People in the photo include Max Munk, aerodynamic researcher; Theodore von Karman; George Lewis, director of research; Henry Reid, engineer in charge; Fred Weick, PRT head; Paul Hemke; Elliott Reid, future Stanford University Professor.

  10. Dr. Wernher von Braun

    NASA Technical Reports Server (NTRS)

    1960-01-01

    Dr. Wernher von Braun served as Marshall Space Flight Center's first director from July 1, 1960 until January 27, 1970, when he was appointed NASA Deputy Associate Administrator for Plarning. Following World War II, Dr. von Braun and his German colleagues arrived in the United States under Project Paperclip to continue their rocket development work. In 1950, von Braun and his rocket team were transferred from Ft. Bliss, Texas to Huntsville, Alabama to work for the Army's rocket program at Redstone Arsenal and later, NASA's Marshall Space Flight Center. Under von Braun's leadership, Marshall developed the Saturn V launch vehicle which took Apollo astronauts to the moon.

  11. Rheologie von Beschichtungen

    NASA Astrophysics Data System (ADS)

    Schäffler, Michael

    Die Rheologie beschreibt die Fließ- und Deformationseigenschaften von Materialien. Der Begriff Rheologie ist aus dem Griechischen abgeleitet: rhein - fließen. Erst im Jahre 1930 entwickelte E.C. Bingham und M. Reiner in Easton (USA) die Rheologie zu einer eigenständigen Wissenschaft. Aber bereits seit dem 17. Jahrhundert wurden wesentliche Einzelbeiträge zu Fließphänomenen veröffentlich, so z.B. 1676 von R. Hooke (Hookesches Gesetz) und 1687 von I. Newton (Newtonsches Gesetz). Die Rheologie hat sich bis heute immer mehr zu einer interdisziplinären Wissenschaft entwickelt, die die mechanischen Eigenschaften von Materialien charakterisiert.

  12. Leopold von Buch

    USGS Multimedia Gallery

    This portrait of Leopold von Buch(1774-1853) was painted in the 1920s by Abner Lowe. Geologist, Paleontologist, and Graduate of the mining academy, Frieburg, Germany, von Buch is largely known for finding flaws in Abraham G. Werner's hypothesis (rocks from aqueous origins). Some of his more importan...

  13. Dr. Wernher von Braun

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Dr. von Braun is looking out from a 10th floor window of building 4200 at the Marshall Space Flight Center (MSFC). He was the first Center Director and served as the Director from July 1960 through February 1970. Following World War II, Dr. von Braun and his German colleagues arrived in the United States under the Project Paperclip (American acquisition of German rocket experts) to continue their rocket development work. In 1950, von Braun and his German Rocket Team (also called the Peenemuende Team) were transferred from Ft. Bliss, Texas to Huntsville, Alabama to work for the Army's rocket program at Redstone Arsenal and later, NASA's Marshall Space Flight Center (MSFC). Under Dr. von Braun's leadership, MSFC developed the Saturn V launch vehicle, which placed the first men, two American astronauts, on the Moon. Wernher von Braun's life was dedicated to expanding man's knowledge through the exploration of space.

  14. Energetische Verwertung von Biomasse

    NASA Astrophysics Data System (ADS)

    Zahoransky, Richard; Allelein, Hans-Josef; Bollin, Elmar; Oehler, Helmut; Schelling, Udo

    Etwa 0,1% der Solarenergie wandeln sich durch Photosynthese aus dem Kohlendioxid der Luft in Biomasse um. Die Biomassen sind als Festbrennstoff nutzbar oder zu gasförmigen Brennstoffen weiterverarbeitbar. Zwei Arten von Biomassen sind zu unterscheiden: Anfallende Biomasse

  15. Bewertung von Fahrzeuggeräuschen

    NASA Astrophysics Data System (ADS)

    Genuit, Klaus; Schulte-Fortkamp, Brigitte; Fiebig, André; Haverkamp, Michael

    Bei der Wahrnehmung und Beurteilung eines Automobils sind unzählige Merkmale und Eigenschaften von Bedeutung. Dabei können Merkmale objektiv-technisch beschrieben werden, wie Angaben zur Motorisierung, Höchstgeschwindigkeit, Drehmoment, zulässige Zuladung, Verbrauch usw. Daneben sind weitere Eigenschaften von Bedeutung, die sich einer einfachen objektiv-technischen Beschreibung entziehen. Hier sind Begriffe zu nennen, wie Sicherheit, allgemeine Qualitätsanmutung, Design, Ergonomie, Komfort, Haptik, Fahrdynamik, Zuverlässigkeit, die deutlich schwieriger objektiv erfassbar und beschreibbar sind (Abb. 4.1).

  16. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (right), Deputy Associate Administrator for Planning, National Aeronautics and Space Administration, inspects the mockup of the Saturn Workshop during a visit marking the 10th anniversary of the Marshall Center. Shown with Dr. Von Braun, from left to right, are Karl Heimburg, Director of the Astronautics Lab; Herman K. Weidner, Director of Science and Engineering, and George Hardy of the Astronautics Lab.

  17. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (right), Deputy Associate Administrator for planning, National Aeronautics and Space Administration, inspects the mockup of the Saturn Workshop during a visit marking the 10th anniversary of the Marshall Center. Shown with Dr. Von Braun, from left to right, are Karl Heimburg, Director of the astronautics lab; Herman K. Weidner, Director of Science and Engineering, and George Hardy of the Astronautics lab.

  18. Jenseits von Halley

    NASA Astrophysics Data System (ADS)

    Calder, Nigel; Lüst, R.; Fischer, D.

    GIOTTO, das spektakulärste Raumprojekt seit der Mondlandung und ein Glanzstück der europäischen Raumforschung, wird von dem versierten Autor Nigel Calder spannend dargestellt. GIOTTO hat sich bis auf 600 km dem Kometen Halley genähert, wurde dabei beschädigt, von der Erde aus repariert und hat danach noch den Kometen Grigg-Skjellerup besucht. Das Buch führt den Leser durch alle Fehlschläge und die glanzvollen Erfolge dieser internationalen Zusammenarbeit unter der Leitung der ESA. Der Autor geht auch auf das ROSETTA-Projekt ein, das derzeit in Vorbereitung ist. Der Übersetzer hat in Zusammenarbeit mit dem Autor und den wissenschaftlichen Projektleitern bei der ESA den Text für die deutsche Ausgabe aktualisiert und ergänzt.

  19. Zur Bestimmung chemischer Verschiebungen der NMR-Frequenzen bei Quadrupolkernen aus den MAS-NMR-Spektren

    NASA Astrophysics Data System (ADS)

    Müller, D.

    Die allgemeinen Ausdrücke für den NMR-Zentralübergang für Quadrupolkerne mit halbzahligem Spin bei Probenrotation, die von BEHRENS [1, 2] unter Berücksichtigung von Quadrupolwechselwirkungseffekten 2. Ordnung für beliebige Neigungswinkel der Rotationsachse abgeleitet wurden, werden für den praktisch interessierenden Fall der Probenrotation um den magischen Winkel (magic angle spinning, MAS) in einer den Ausgangsformeln für das Ruhespektrum (ohne Probenrotation) analogen Form dargestellt. Am Beispiel der 27Al-NMR-Spektren zweier Aluminate wird die Theorie überprüft und zur exakten Ermittlung der chemischen Verschiebungswerte aus den MAS-Spektren eingesetzt.Translated AbstractDetermination of Chemical Shifts of NMR-Frequencies of Quadrupolar Nuclei from the MAS-NMR SpectraThe general expressions for the NMR central transition of rotating samples with quadrupolar nuclei of half-integer spins, derived by BEHRENS [1, 2] for arbitrary angles of inclination of the spinning axis considering second-order quadrupolar effects, are presented for the practically interesting case of magic angle spinning (MAS) in a form analogous to the expressions for the resting sample. The theory is tested and used for the exact determination of the chemical shift values from the MAS-27Al-NMR spectra of two representative aluminates.

  20. Halbautomatische Segmentierung von Pulmonalgefäßen in CT Daten als Referenz zur Validierung automatischer Verfahren

    NASA Astrophysics Data System (ADS)

    Kaftan, Jens N.; Bakai, Annemarie; Maier, Florian; Aach, Til

    Das Segmentieren von Pulmonalgefäßen in Computertomographie (CT) Daten wurde schon vielfach behandelt und wird z.B. bei der computerunterstützten Detektion von Lungenembolien angewendet. Vielen Segmentierverfahren fehlt jedoch eine quantitative Validierung aufgrund mangelnder Referenzsegmentierungen. Wir stellen ein System zur halbautomatischen Segmentierung von Blutgefäßen in definierten Bereichen der Lunge basierend auf dem Random-Walker-Algorithmus vor. Durch Initialisierung der Methode mittels automatisch generierter Saatpunkte wird die Effizienz des Verfahrens erhöht und die erforderliche Benutzerinteraktion reduziert. Die resultierenden Segmentierungen können zur Validierung von automatischen Verfahren verwendet werden. Exemplarisch evaluieren wir ein vollautomatisches Segmentierverfahren basierend auf dem Fuzzy-Connectedness-Algorithmus.

  1. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Shown viewing the Apollo telescope mockup are, from left to right, Charles Donlan, deputy associate administrator for manned space flight; Dr. Wernher Von Braun, Marshall Space Flight Center director; William Horton, astrionics lab; Dr. Thomas Paine, NASA deputy administrator; Warner Kuers, director of the ME lab.

  2. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A camerman catches Dr. Wernher Von Braun, Director of the Marshall Space Flight Center, his son, Peter, and daughter, Martgrit, as they arrive at the employee picnic held to celebrate man's first landing on the moon 6 days earlier. In the foreground is David R. Newby, Director of Administration and Technical Services at the Marshall Space Flight Center.

  3. The Molecular Genetics of von Willebrand Disease

    PubMed Central

    Berber, Ergül

    2012-01-01

    Quantitative and/or qualitative deficiency of von Willebrand factor (vWF) is associated with the most common inherited bleeding disease von Willebrand disease (vWD). vWD is a complex disease with clinical and genetic heterogeneity. Incomplete penetrance and variable expression due to genetic and environmental factors contribute to its complexity. vWD also has a complex molecular pathogenesis. Some vWF gene mutations are associated with the affected vWF biosynthesis and multimerization, whereas others are associated with increased clearance and functional impairment. Moreover, in addition to a particular mutation, type O blood may result in the more severe phenotype. The present review aimed to provide a summary of the current literature on the molecular genetics of vWD. Conflict of interest:None declared. PMID:24385719

  4. Dr. von Braun at 'Wernher von Braun Day' Celebration

    NASA Technical Reports Server (NTRS)

    1970-01-01

    In 1970 Marshall Space Flight Center (MSFC) Director Dr. Wernher von Braun (right) was reassigned to NASA Headquarters to serve as Deputy Associate Administrator for Plarning. Prior to his transfer, Dr. von Braun was honored for his career in Huntsville, Alabama, with the celebration of 'Wernher von Braun Day.' Among those participating were Alabama Governor Albert Brewer (left) and Alabama Senator John Sparkman (center). (Courtesy of Huntsville/Madison County Public library)

  5. [von Recklinghausen's neurofibromatosis].

    PubMed

    Alcaz, S; Djordjevi?, M; Dragutinovi?, G; Lavrni?, S; Apostolski, S

    1991-01-01

    We present a case of unusual clinical picture of the well defined Morbus Von Recklinghausen. In a 35-year-old male patient, after an uncontrolled rapid movement of the neck, the disease was suddenly manifested with spastic quadriparesis. Three years later the clinical picture showed spastic quadriplegia. Antalgic torticollis confirmed by X-ray of the neck clearly showed vertebral subluxation at the level of C3-C4. However, additional magnetic resonance imaging revealed large extradural tumorous formation at the level of C1-C2, and two small oval tumours in the splenium of the corpus callosum as well as in the left lateral ventricle. "Café au lait" spots, "molluscum fibrosum" and few subcutaneous fibromas appeared as skin changes which explained the possible nature of the registered intracranial and intraspinal tumours. Neurosurgery has been performed at the spinal level with good results; it confirmed the diagnosis of Von Recklinghausen's Neurofibromatosis. PMID:1807001

  6. Missbrauchspotential von Verzeichnisdienst-Metadaten in LDAP-basierten System- und Benutzerverwaltungen

    NASA Astrophysics Data System (ADS)

    Pluta, Daniel

    Metadaten stellen Zusatzinformationen über elektronisch gespeicherte Kerninformationen zur Verfügung. Sie ergänzen die eigentliche Hauptinformation um nützliche Details. In vielen Bereichen werden Metadaten gespeichert und stehen zur Auswertung zur Verfügung. Alle IT-nahen Systeme, angefangen im Konsumerbereich (z.B. digitale Kameras) bis hin zu unternehmenskritischen Applikationen führen im Hintergrund Metadaten - parallel zu den eigentlichen Hauptdaten. Metadaten im Allgemeinen sind per se als neutral, d.h. weder positiv noch negativ, zu bewerten. So wirken sich diese häufig positiv auf das Finden und Sortieren von digitalen Dokumenten aus. Negativ treten Metadaten eigentlich immer nur dann in Erscheinung, sobald diese ursprünglich zusätzlichen und nützlichen (und daher im Gegensatz zu den Hauptdaten nicht besonders beachteten bzw. geschützten) Informationen entgegen ihrer Bestimmung, zweckentfremdet werden. Auch Verzeichnisdienste verfügen über solche nützlichen Metadaten zu den jeweils in ihnen gespeicherten Inhalten. Ob, und wenn ja wie weit diese nützlichen Inhalte auch ein Risiko darstellen können wird im Rahmen dieses Artikels anhand eines konkreten Szenarios aus dem Umfeld des Systemmanagements gezeigt.

  7. Theodore von Karman

    NASA Technical Reports Server (NTRS)

    1950-01-01

    Dr. Theodore von Karman, co-founder of the Jet Propulsion Laboratory (JPL) Pasadena, California was an aeronautical theoretician. His contributions in the fields of aerodynamics and aeronautical engineering are well documented and well known to every aerospace engineer. He was the first winner of the prestigious U.S. Medal of Science presented to him by President John F. Kennedy. As well as being co-founder of JPL, he also was principal founder of a major rocket propulsion firm (Aerojet-General Corp.), the top science advisor to the U.S. Air Force during its transition to jet propulsion aircraft and the top science advisor to NATO. He was, during much of this time, the fountainhead of aerodynamic thought as head of the Guggenheim Aeronautical Laboratory at the California Institute of Technology (GALCIT) in Pasadena, California. In the May 1956 issue of the Journal of Aeronautical Sciences, it was said of him that 'No other man has had so great an impact on the development of aeronautical science in this country. Hundreds of young men became his students and scientific collaborators and were inspired to greater effort.' Dr. William H. Pickering, then director of JPL said in 1960 'We wouldn't have an aeronautical science as we know it today, if it weren't for Dr. Thoedore von Karman.' Under his guidance, Caltech's 10 foot wind tunnel was designed, built and operated. Industry firms such as Douglas, Northrop, Hughes, Lockheed, North American, Vultee and Consolidated all tested new aeronautical designs and concepts in GALCIT's tunnel. Even Boeing's own high-speed wind tunnel was heavily influenced by suggestions from von Karman. The National Advisory Committee for Aeronautics (NACA) became so concerned about GALCIT's growing influence over West coast aviation, it erected the Ames Laboratory in Sunnyvale, California in part to deter an ever widening aeronautical gap that had formed between NACA and GALCIT. From 1936 to 1940, Caltech stood alone as the only university-based rocket research center. Von Karman gambled his prestige by supporting Frank Malina and H.S. Tsien's work on rocketry. Other institutions of higher learning dismissed such research as 'fantastical' and left such endeavors to visionaries like Robert Goddard. Foundational theoretical research by Von Karman gave rise to the first successful solid-fuel rocket engine firings. This led to federal funding for studies that lead to a form of aircraft rocket propulsion called Jet Assisted Take-Off or (JATO). Success in this endeavor led to von Karman establishing two more highly regarded institutions; both originally dedicated to rocketry: the Aerojet Engineering Company and the Jet Propulsion Laboratory. The last years of his life were spent in Paris, his favorite city. His interest in aeronautical research and contributions to it never waned. He organized in Paris the NATO Advisory Group for Aeronautical Research and Development (AGARD). Staffed by American and European scientists eager to serve, its many committees investigated such disciplines as propulsion, aerodynamics and electronics. The legacy of his personable leadership and 'soft touch' approach to problem solving was only equalled by his genius.

  8. Dr. Wernher Von Braun

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Thomas Paine, Deputy Administrator of the National Aeronautics and Space Administration, examines an ordinary man's shoe outfitted for use in the Saturn I workshop. Pictured from the left in the Saturn I workshop mockup are William Brooksbank, propulsion and vehicle engineering laboratory; Dr. Paine; Dr. Wernher Von Braun, Marshall Center director; Colonel Clare F. Farley, Executive Officer in the Office Of The Administrator; and Charles J. Donlan, Deputy Associate Administrator for Manned Space Flight, Technical. the shoe Dr. Paine is holding has a unique fastener built into the sole to allow an astronaut to move about on the workshop floor and to remain in one position if he desires.

  9. Entwickeln von produktbegleitenden Dienstleistungen

    NASA Astrophysics Data System (ADS)

    Strube, Michaela; Nixdorf, Steffen; Dahl, Bodo

    Leistungselektronische Komponenten werden aufgrund ihrer komplexen Baustrukturen und der häufig geringen Losgrößen hauptsächlich in zeitintensiver Handarbeit gefertigt. Damit solche Prozesse am Standort Deutschland verbleiben können, ist es notwendig, deren Effizienz zu steigern. Neue Formen der Arbeitsteilung zwischen Zulieferern, Herstellern und Kunden können einen wichtigen Beitrag leisten, sind aber ohne produktbegleitende Dienstleistungen nicht realisierbar [Lay u. Jung Erceg 2002]. Volkholz fasst das wie folgt zusammen: Wer für den Erhalt von industrieller Produktion in Deutschland ist, muss sich für Dienstleistungen interessieren" [Volkholz 1996]. Die produktbegleitende Dienstleistung als Ergänzung des Fertigungsprozesses und Erweiterung des Angebots muss konsequent, systematisch und zielgerichtet entwickelt werden. Nur dann kann diese Dienstleistungsinnovation über einen marktgerechten Preis beim Abnehmer platziert werden.

  10. John von Neumann Birthday Centennial

    SciTech Connect

    Grcar, Joseph F.

    2004-11-12

    In celebration of John von Neumann's 100th birthday, a series of four lectures were presented on the evening of February 10, 2003 during the SIAM Conference on Computational Science and Engineering in San Diego. The venue was appropriate because von Neumann spent much of the later part of his life, in the 1950's, as an unofficial ambassador for computational science. He was then the only senior American scientist who had experience with the new computers (digital, electronic, and programmable) and a vision of their future importance. No doubt he would have relished the chance to attend a meeting such as this. The first speaker, William Aspray, described the ''interesting times'' during which computers were invented. His remarks were based on his history [1] of this period in von Neumann's life. We were honored to have John von Neumann's daughter, Marina von Neumann-Whitman, as our second speaker. Other accounts of von Neumann's life can be found in books by two of his colleagues [2] and [3]. Our third speaker, Peter Lax, provided both mathematical and international perspectives on John von Neumann's career. Finally, Pete Stewart spoke about von Neumann's numerical error analysis [4] in the context of later work; this talk did not lend itself to transcription, but readers may consult the historical notes in [5]. Our thanks to all the speakers for a remarkable evening. We are grateful to the DOE Applied Mathematical Sciences (AMS) program for partially supporting these lectures. Thanks are also due to SIAM and William Kolata, to our emcee, Gene Golub, to Paul Saylor for recording and editing, and to Barbara Lytle for the transcriptions. More about von Neumann's work can be learned from the recent American Mathematical Society proceedings [6].

  11. Sulfation of von Willebrand factor

    SciTech Connect

    Carew, J.A.; Browning, P.J.; Lynch, D.C. )

    1990-12-15

    von Willebrand factor (vWF) is a multimeric adhesive glycoprotein essential for normal hemostasis. We have discovered that cultured human umbilical vein endothelial cells incorporate inorganic sulfate into vWF. Following immunoisolation and analysis by polyacrylamide or agarose gel electrophoresis, metabolically labeled vWF was found to have incorporated (35S)-sulfate into all secreted multimer species. The time course of incorporation shows that sulfation occurs late in the biosynthesis of vWF, near the point at which multimerization occurs. Quantitative analysis suggests the presence, on average, of one molecule of sulfate per mature vWF subunit. Virtually all the detectable sulfate is released from the mature vWF subunit by treatment with endoglycosidases that remove asparagine-linked carbohydrates. Sulfated carbohydrate was localized first to the N-terminal half of the mature subunit (amino acids 1 through 1,365) by partial proteolytic digestion with protease V8; and subsequently to a smaller fragment within this region (amino acids 273 through 511) by sequential digestions with protease V8 and trypsin. Thus, the carbohydrate at asparagine 384 and/or 468 appears to be the site of sulfate modification. Sodium chlorate, an inhibitor of adenosine triphosphate-sulfurylase, blocks sulfation of vWF without affecting either the ability of vWF to assemble into high molecular weight multimers or the ability of vWF multimers to enter Weible-Palade bodies. The stability of vWF multimers in the presence of an endothelial cell monolayer also was unaffected by the sulfation state. Additionally, we have found that the cleaved propeptide of vWF is sulfated on asparagine-linked carbohydrate.

  12. von Braun and German Publisher

    NASA Technical Reports Server (NTRS)

    1969-01-01

    In this photograph, Guenter Ogger of Capitol Magazine, West Germany, greets Marshall Space Flight Center Director, Dr. Wernher von Braun. Mr. Ogger interviewed the famous rocket scientist for his magazine.

  13. von Willebrand Disease (For Parents)

    MedlinePLUS

    ... in 1926. As a group, bleeding disorders (including hemophilia ) are rare. Von Willebrand disease is the most ... that is missing or defective when someone has hemophilia.) People with vWD have bleeding problems because the ...

  14. Von Willebrand Disease (For Parents)

    MedlinePLUS

    ... flow of blood ) is a complex process involving platelets and proteins called clotting factors. Von Willebrand factor ... easily Type 2B: the factor sticks to the platelets too well, leading to clumping of the platelets, ...

  15. Renaturierung von Sandökosystemen im Binnenland

    NASA Astrophysics Data System (ADS)

    Schwabe-Kratochwil, Angelika; Kratochwil, Anselm

    Das Vorkommen von Sandökosystemen im Binnenland (Flugsand- und Decksandfelder, Dünen) ist vor allem an Sand-Akkumulationen der vorletzten Eiszeit (in Nordeuropa: Saaleeiszeit und Sand-Ablagerungen an größeren Flüssen gebunden. So finden wir die Verbreitungsschwerpunkte von binnenländischen Sandökosystemen in Mitteleuropa einerseits vor allem im Bereich der flächenhaften saalezeitlichen Ablagerungen in den Niederlanden und in Norddeutschland (Castel et al. 1989), andererseits kommen Sandökosysteme des Binnenlandes linear in den Flussgebieten z.B. von Maas, Rhein, Ems, Elbe, Oder und Regnitz vor. In Niederösterreich fanden sich einst großflächige Dünen- und Flugsandgebiete im Marchfeld östlich von Wien (Wiesbauer et al. 1997). Die Flugsandbildung setzte bereits im Spätglazial ca. 11000 v. Chr. ein, als eine den Sand fixierende Vegetation noch fehlte. Es bildeten sich im norddeutschen Raum aus den leicht verwehbaren Talsanden bereits um 9000 v. Chr.

  16. Ökologische Aspekte von Thin Clients

    NASA Astrophysics Data System (ADS)

    von Knermann, Christian

    Hersteller von IT-Technologie haben angesichts der Debatte um Klimaschutz und Nachhaltigkeit erkannt, dass für Endkunden, ob privat oder gewerblich, auch ökologische Gesichtspunkte beim Kauf von PC, Laptop oder Netzwerkgeräten eine immer größere Rolle spielen und Energie- oder Ökoeffizienz der Geräte kaufentscheidend wirken können. Betrachtet und bewertet wurden bislang aber hauptsächlich isolierte Einzelaspekte, wie der Energieverbrauch in der Nutzungsphase oder der Einsatz toxikologisch unbedenklicher Stoffe. Was fehlt, ist eine ganzheitliche Ausrichtung auf Nachhaltigkeit über die Lebensphasen Produktion, Nutzung sowie Recyling/Entsorgung.

  17. Zebrafish von Willebrand Factor

    PubMed Central

    Carrillo, Maira; Kim, Seongcheol; Rajpurohit, Surendra Kumar; Kulkarni, Vrinda; Jagadeeswaran, Pudur

    2010-01-01

    von Willebrand factor (vWF) is a large protein involved in primary hemostasis. A dysfunction in this protein or an insufficient production of the protein leads to improper platelet adhesion/aggregation, resulting in a bleeding phenotype known as von Willebrand disease (vWD). To gain a better understanding of vWF interactions in vivo, the use of zebrafish as a model is ideal because of the transparency of the embryos and larvae. In this article, we examined the presence and function of vWF in hemostasis of zebrafish utilizing a variety of molecular methods. Using RT-PCR and antibody staining, we have shown that vWF mRNA is present in thrombocytes. Through antibody staining, we demonstrated vWF is synthesized in blood vessels. The role of zebrafish vWF in hemostasis was established through knockdown methods using vWF morpholino (vWF MO) antisense oligonucleotides. Embryos injected with vWF MO at the one to four cell stages resulted in a bleeding phenotype. Injection of embryos with vWF MO also caused an increase in time to occlusion within arteries in larvae upon laser induced injury. We then used vWF-specific Vivo-Morpholinos (VMO) to induce vWF knockdown in adult zebrafish by targeting the exon homologous to the human exon 28 of the vWF gene. The reduced ristocetin-mediated agglutination of thrombocytes in a plate tilting assay, using blood from adult zebrafish injected with VMO, provided evidence that vWF is involved in the hemostatic process. We also administered desmopressin acetate to larvae and adults which resulted in enhanced aggregation/agglutination of thrombocytes. Zebrafish genome database analysis revealed the presence of GPIb? gene. It also revealed the exon of zebrafish vWF gene corresponding to exon 28 of human vWF gen is highly similar to the exon 28 of human vWF gene, except that it has an insertion that leads to a translated peptide sequence that separates the two A domains coded by this exon. This exon is also conserved in other fishes. In summary, we established that zebrafish vWF has a role similar to that of vWF found in humans, thus, making zebrafish a useful model for studying the cell biology of vWF in vivo. PMID:21035359

  18. Richard von Volkmann

    PubMed Central

    Willy, Christian; Schneider, Peter; Engelhardt, Michael; Hargens, Alan R.

    2008-01-01

    Richard von Volkmann (1830–1889), one of the most important surgeons of the 19th century, is regarded as one of the fathers of orthopaedic surgery. He was a contemporary of Langenbeck, Esmarch, Lister, Billroth, Kocher, and Trendelenburg. He was head of the Department of Surgery at the University of Halle, Germany (1867–1889). His popularity attracted doctors and patients from all over the world. He was the lead physician for the German military during two wars. From this experience, he compared the mortality of civilian and war injuries and investigated the general poor hygienic conditions in civilian hospitals. This led him to introduce the “antiseptic technique” to Germany that was developed by Lister. His powers of observation and creativity led him to findings and achievements that to this day bear his name: Volkmann’s contracture and the Hueter-Volkmann law. Additionally, he was a gifted writer; he published not only scientific literature but also books of children’s fairy tales and poems under the pen name of Richard Leander, assuring him a permanent place in the world of literature as well as orthopaedics. PMID:18196438

  19. Exponential Size Distribution of von Willebrand Factor

    PubMed Central

    Lippok, Svenja; Obser, Tobias; Müller, Jochen P.; Stierle, Valentin K.; Benoit, Martin; Budde, Ulrich; Schneppenheim, Reinhard; Rädler, Joachim O.

    2013-01-01

    Von Willebrand Factor (VWF) is a multimeric protein crucial for hemostasis. Under shear flow, it acts as a mechanosensor responding with a size-dependent globule-stretch transition to increasing shear rates. Here, we quantify for the first time, to our knowledge, the size distribution of recombinant VWF and VWF-eGFP using a multilateral approach that involves quantitative gel analysis, fluorescence correlation spectroscopy, and total internal reflection fluorescence microscopy. We find an exponentially decaying size distribution of multimers for recombinant VWF as well as for VWF derived from blood samples in accordance with the notion of a step-growth polymerization process during VWF biosynthesis. The distribution is solely described by the extent of polymerization, which was found to be reduced in the case of the pathologically relevant mutant VWF-IIC. The VWF-specific protease ADAMTS13 systematically shifts the VWF size distribution toward smaller sizes. This dynamic evolution is monitored using fluorescence correlation spectroscopy and compared to a computer simulation of a random cleavage process relating ADAMTS13 concentration to the degree of VWF breakdown. Quantitative assessment of VWF size distribution in terms of an exponential might prove to be useful both as a valuable biophysical characterization and as a possible disease indicator for clinical applications. PMID:24010664

  20. Quantitative genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The majority of economically important traits targeted for cotton improvement are quantitatively inherited. In this chapter, the current state of cotton quantitative genetics is described and separated into four components. These components include: 1) traditional quantitative inheritance analysis, ...

  1. [Von Willebrand and his factor].

    PubMed

    van Gijn, Jan; Gijselhart, Joost P

    2011-01-01

    Erik Adolf von Willebrand (1870-1949) studied medicine in Helsinki, where he subsequently joined the staff at the Deaconess Hospital. Haematological disorders were his main interest. In 1924 he was consulted about 5-year-old Hjördis S. She suffered from a severe bleeding disorder, as did six of her ten siblings; three of her sisters had died. In a Finnish article in a Journal in 1926 (in the Swedish language) he plotted the family pedigree (bleeding disorder in three preceding generations, on the part of both parents). Von Willebrand also distinguished the disorder from haemophilia and thrombopathies with purpura. His conjecture that the disorder was a special form of thrombocyte dysfunction would eventually be borne out, though the key factor is severe deficiency of a specific plasma protein. In milder, autosomal dominant forms of the disease, the protein is partly deficient or abnormal. PMID:21329541

  2. Von der Quantenmechanik zum Materialdesign

    NASA Astrophysics Data System (ADS)

    Eyert, Volker; Eckern, Ulrich

    2000-11-01

    Die enormen Fortschritte der theoretischen Festkörperphysik im 20. Jahrhundert sind eng verknüpft mit der Entdeckung der Quantenmechanik und der Entwicklung von schnellen Verfahren zur Berechnung der elektronischen Struktur kondensierter Materie. Letztere bilden heute die Basis sowohl für ein vertieftes Verständnis grundlegender physikalischer Fragestellungen als auch die Herstellung neuer Materialien mit maßgeschneiderten Eigenschaften.

  3. Treatment of von Willebrand Disease.

    PubMed

    Curnow, Jennifer; Pasalic, Leonardo; Favaloro, Emmanuel J

    2016-03-01

    Congenital von Willebrand disease (VWD) and acquired von Willebrand syndrome (AVWS) reflect conditions caused by von Willebrand factor (VWF) deficiency and/or defects. VWD is the most common inherited bleeding disorder and AVWS arises from a variety of causes. Since VWF stabilizes and protects factor VIII (FVIII) in the circulation, this is also reduced in many patients with VWD. The treatment of VWD and AVWS therefore primarily entails replacement of VWF, and sometimes FVIII, to protect against bleeding. This may entail the use of VWF concentrates (currently plasma-derived) and/or FVIII concentrates (currently plasma-derived or more increasingly recombinant forms), and/or desmopressin to release endogenous VWF in subgroups of patients. For AVWS additional treatment of the underlying condition is also required. Adjunct therapies include antifibrinolytics. Globally, various formulations exist for both VWF and FVIII concentrates and are differentially available based on manufacturer marketing or regulatory approvals/clearances in different geographies. Also, guidelines for treatment of VWD vary for different localities and recombinant VWF is undergoing clinical trials. The current review provides an overview of the treatment of VWD as currently practiced in developed countries, and also provides a glimpse towards the future. PMID:26838696

  4. Dr. von Braun Briefing Walt Disney

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Dr. von Braun began his association with Walt Disney in the 1950s when the rocket scientist appeared in three Disney television productions related to the exploration of space. Years later, Dr. von Braun invited Disney and his associates to tour the Marshall Space Flight Center (MSFC) in Huntsville, Alabama. This photograph is dated April 13, 1965. From left are R.J. Schwinghamer from the MSFC, Disney, B.J. Bernight, and Dr. von Braun.

  5. Quantenphysik Interferometrie von C70-Molekülen

    NASA Astrophysics Data System (ADS)

    Ziegler, Thomas

    2002-05-01

    Interferenzversuche mit Neutronen und schweren Atomen stellen kein großes Problem mehr dar, selbst die Welleneigenschaften von C60-und C70-Molekülen wurden bereits nachgewiesen. Allerdings stößt man bei der Realisation immer feinerer Gitter mit Gitterkonstanten von etwa 100 nm im Fall dieser Moleküle auf technische Probleme. Wissenschaftlern der Universität Wien ist es jüngst gelungen, ein so genanntes Talbot-Lau-Interferometer zu realisieren und die Welleneigenschaften von C70 mit einer bislang unerreichten Qualität nachzuweisen [1].

  6. EVITA - Das Prüfverfahren zur Beurteilung von Antikollisionssystemen

    NASA Astrophysics Data System (ADS)

    Hoffmann, Jens; Winner, Hermann

    Bei der Entwicklung von Fahrerassistenzsystemen (FAS) für die Vermeidung von Unfällen sind geeignete Testmethoden für das Erzeugen von Bewertungen erforderlich. Für eine größtmögliche Übertragbarkeit der Versuche sind realitätsnahe und repräsentative Szenarien darzustellen. Dabei gilt bisher, dass eine Vergrößerung der Realitätsnähe mit einer enormen Vergrößerung des Aufwands einhergeht. Die Testmethoden mit Probanden für in kritischen Situationen unterstützende FAS müssen vor allem sicher für die beteiligten Versuchspersonen, aber auch reproduzierbar sein. Da bisher geeignete Verfahren fehlen, stellt dieser Test von Antikollisionssystemen in kritischen Situationen eine große Herausforderung dar.

  7. Reflexionseigenschaften von Windenergieanlagen im Funkfeld von Funknavigations- und Radarsystemen

    NASA Astrophysics Data System (ADS)

    Sandmann, S.; Divanbeigi, S.; Garbe, H.

    2015-11-01

    Die hier behandelte Untersuchung befasst sich mit den Störungen des elektrischen Feldes einer Doppler Very High Frequency Omnidirectional Radio Range Navigationsanlage (DVOR) in der Gegenwart von Windenergieanlagen (WEA). Hierfür wird die Feldstärke auf 25 konzentrischen Kreisbahnen, sog. Orbit Flights verschiedener Höhen und mit verschiedenen Radien rund um die DVOR-Anlage numerisch simuliert. Insbesondere werden die Einflüsse diverser Parameter der WEA wie deren Anzahl, Position, Rotorwinkel, Turmhöhe und Rotordurchmesser auf die Feldverteilung herausgestellt, sowie die Anwendbarkeit der Simulationsmethode Physical Optics (PO) durch Vergleich der Simulationsergebnisse mit denen der Multi Level Fast Multipol Method (MLFMM) untersucht.

  8. Walt Disney and Dr. Wernher von Braun

    NASA Technical Reports Server (NTRS)

    1954-01-01

    Dr. Werhner von Braun, then Chief, Guided Missile Development Operation Division at Army Ballistic Missile Agency (ABMA) in Redstone Arsenal, Alabama, was visited by Walt Disney in 1954. In the 1950's, von Braun worked with Disney Studio as a technical director, making three films about space exploration for television. A model of the V-2 rocket is in background.

  9. Dr. von Braun Tries Out the NBS

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Marshall Space Flight Center (MSFC) Director, Dr. von Braun, is shown fitted with suit and diving equipment as he prepares for a tryout in the MSFC Neutral Buoyancy Simulator (NBS). Weighted to a neutrally buoyant condition, Dr. von Braun was able to perform tasks underwater which simulated weightless conditions found in space.

  10. Dr. Wernher Von Braun greeting dignitaries.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun, left, greets vice president Spiro T. Agnew in the Launch Control Center for the Apollo 14 mission. Between Dr. Von Braun and Mr. Agnew are their Royal Highnesses, The Prince and Princess of Spain. The royal visitors greeted the launch control team in th enter after the launch of Apollo 14.

  11. Infinite Measures on von Neumann Algebras

    NASA Astrophysics Data System (ADS)

    Goldstein, Stanis?aw; Paszkiewicz, Adam

    2015-12-01

    Infinite measures on von Neumann algebras are classified according to properties analogous to those from classical measure theory. These properties are carefully examined in case of semifinite von Neumann algebras. Some examples are also given and the direction for further research indicated.

  12. Ludwig von Mises: An Annotated Bibliography.

    ERIC Educational Resources Information Center

    Gordon, David

    A 117-item annotated bibliography of books, articles, essays, lectures, and reviews by economist Ludwig von Mises is presented. The bibliography is arranged chronologicaly, and is followed by an alphabetical listing of the citations, excluding books. An index and information on the Ludwig von Mises Institute at Auburn University (Alabama) are…

  13. Dr. Wernher von Braun In His Office

    NASA Technical Reports Server (NTRS)

    1964-01-01

    Dr. Wernher von Braun served as Marshall Space Flight Center's first director from July 1, 1960 until January 27, 1970, when he was appointed NASA Deputy Associate Administrator for Planning. Following World War II, Dr. von Braun and his German colleagues arrived in the United States under Project Paperclip to continue their rocket development work. In 1950, von Braun and his rocket team were transferred from Ft. Bliss, Texas to Huntsville, Alabama to work for the Army's rocket program at Redstone Arsenal and later, NASA's Marshall Space Flight Center. Under von Braun's leadership, Marshall developed the Saturn V launch vehicle which took Apollo astronauts to the moon. This photo depicts von Braun in his office at MSFC.

  14. Quantitative analysis

    PubMed Central

    Nevin, John A.

    1984-01-01

    Quantitative analysis permits the isolation of invariant relations in the study of behavior. The parameters of these relations can serve as higher-order dependent variables in more extensive analyses. These points are illustrated by reference to quantitative descriptions of performance maintained by concurrent schedules, multiple schedules, and signal-detection procedures. Such quantitative descriptions of empirical data may be derived from mathematical theories, which in turn can lead to novel empirical analyses so long as their terms refer to behavioral and environmental events. Thus, quantitative analysis is an integral aspect of the experimental analysis of behavior. PMID:16812400

  15. Automatische Qualitätsmessung von Retina-Fundusbildern

    NASA Astrophysics Data System (ADS)

    Paulus, Jan; Meier, Jörg; Bock, Rüdiger; Hornegger, Joachim; Michelson, Georg

    Zur frühzeitigen Diagnose von Erkrankungen am Augenhintergrund existieren automatische Bildverarbeitungsmethoden. Für die Effektivität solcher Verfahren und für die ärztliche Bewertung ist die Bildqualität der Eingabedaten entscheidend. Wir stellen einen neuen segmentierungsfreien Algorithmus zur automatischen Qualitätsmessung einzelner Fundusbilder vor, der Clustering-Merkmale, Schärfemaße und globale Bildstatistiken kombiniert. Die Güte der Methode wird mit einem etablierten Verfahren zur Qualitätsmessung von Retina-Fundusbildern verglichen, das nur Clustering-Merkmale auf gefilterten Bildern verwendet. Der neue Algorithmus zeigt dabei auf 302 Fundusfotos mit einer Klassifikationsgenauigkeit von 90,3% eine deutlich höhere Zuverlässigkeit als das Vergleichsverfahren mit 69,5%.

  16. Surgery in von Willebrand's disease.

    PubMed Central

    Nilsson, I M; Bergentz, S E; Larsson, S A

    1979-01-01

    Fifty-eight major surgical procedures were performed in 38 patients with von Willebrand's disease (VWD), one of the most common of the inheritable hemorrhagic disorders. Specific treatment with fraction I-0, (AHF-Kabi) in addition to a fibrinolytic inhibitor, was given to all patients. The effect of the treatment was checked by measuring the Duke bleeding time and factor VIII:C level. A marked difference between hemophilia and VWD from a surgical point of view is demonstrated. While most of the surgery in hemophiliacs is performed for severe joint deformities, contractures and blood cysts, surgery in VWD is mostly general surgery, often necessitated by massive hemorrhages from mucous membranes. PMID:316311

  17. [Von Hippel-Lindau syndrome].

    PubMed

    Reich, H; Hollwich, F

    1984-06-01

    The von Hippel-Lindau syndrome is an autosomal dominant condition that comprises, apart from angiomas of the retina, the cerebellum, the spinal cord, and the cerebrum, also cystic and blastomatous dysplasias resulting from maldevelopment, namely cystic kidney and pancreas, hypernephroma, and pheochromocytoma. Early observers of the syndrome were the English neurologist John Hughlings Jackson (1872) and the German ophthalmologist Hugo Magnus (1874). The typical association of angiomas of the retina with the cerebellum was first described in 1905 by the Prague ophthalmologist Wilhelm Czermak, long before Lindau (1926). The fact that hypernephromas and pheochromocytomas may form parts of it characterizes the syndrome as a polyneoplastic hereditary disease and the sufferers as members of families at risk. Since the ophthalmologist is often the first to recognize this disease by direct inspection of the fundi, he is responsible for ensuring proper medical care for the affected person and his or her entire family. PMID:6384634

  18. Quantenphasenübergänge: Von Ordnung zu Unordnung durch Quantenfluktuationen

    NASA Astrophysics Data System (ADS)

    Vojta, Thomas

    Bei konventionellen Phasenübergängen wie dem Schmelzen von Eis wird die makroskopische Ordnung durch thermische Fluktuationen zerstört. Makroskopische Ordnung kann aber auch am Nullpunkt der Temperatur verloren gehen, und zwar durch Quantenfluktuationen aufgrund der Heisenbergschen Unschärfe.

  19. Von Hippel-Lindau Disease (VHL)

    MedlinePLUS

    ... NINDS Funding Information Research Programs Training & Career Awards Enhancing Diversity Find People About NINDS NINDS Von Hippel- ... Funding | News From NINDS | Find People | Training | Research | Enhancing Diversity Careers@NINDS | FOIA | Accessibility Policy | Contact Us | ...

  20. Von Glasersfeld's Radical Constructivism: A Critical Review.

    ERIC Educational Resources Information Center

    Hardy, Michael D.; Taylor, Peter C.

    1997-01-01

    Explores the promises that von Glasersfeld's constructivism holds for the reform of science and mathematics education. Argues that a powerful social epistemology is needed to serve as a referent for regenerating the culture of science education. Contains 48 references. (DDR)

  1. Genetics Home Reference: Von Willebrand disease

    MedlinePLUS

    ... mildest and most common of the three types, accounting for 75 percent of affected individuals. Type 3 ... Where can I find information about diagnosis or management of von Willebrand disease? These resources address the ...

  2. Genetics Home Reference: Von Willebrand disease

    MedlinePLUS

    ... disease is a bleeding disorder that slows the blood clotting process, causing prolonged bleeding after an injury. People ... The VWF gene provides instructions for making a blood clotting protein called von Willebrand factor, which is essential ...

  3. Von Kármán between Aachen and Pasadena

    NASA Astrophysics Data System (ADS)

    Krause, Egon; Kalkmann, Ulrich

    2013-05-01

    In the Introduction the reader is referred back to the academic ceremonials held after Theodore von Kármán's death in Aachen in May 1963. His work as the first director of the Aerodynamisches Institut (Institute of Aerodynamics) of the RWTH Aachen University of Technology from 1913 on and his initiative to re-establish international cooperation after World War I, resulting in the International Union of Theoretical and Applied Mechanics (IUTAM), are commented on. The following chapter describes von Kármán's relation to his former teacher Ludwig Prandtl. Some of von Kármán's scientific contributions during his time in Aachen are briefly reviewed. Thereafter, his first contacts to the California Institute of Technology are covered. Finally, the scientific and political circumstances, which led to von Kármán's decision to leave Germany in the early thirties, are elucidated in some detail. The English translation of the titles of the Aachen papers is given in Appendix I.

  4. Die Paketversicherung von MathPost

    NASA Astrophysics Data System (ADS)

    Daume, Peggy

    Angesichts der fundamentalen Bedeutung des Versicherungsgedankens für die menschliche Existenz kann das Versicherungswesen auf eine lange Geschichte zurückblicken. Dabei lassen sich zwei Grundformen von Versicherungen unterscheiden, die sich gegenseitig beeinflusst und gegenüber anderen Formen durchgesetzt haben.

  5. Childhood Picture of Dr. von Braun

    NASA Technical Reports Server (NTRS)

    1912-01-01

    This is a childhood picture of Dr. von Braun (center) with his brothers. Dr. Wernher von Braun was born in Wirsitz, Germany, March 23, 1912. His childhood dreams of marned space flight were fulfilled when giant Saturn rockets, developed under his direction at NASA's Marshall Space Flight Center, boosted the manned Apollo spacecraft to the Moon. His life was dedicated to expanding man's knowledge through the exploration of space.

  6. Dr. von Braun With German Rocket Experimenters

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Dr. von Braun was among a famous group of rocket experimenters in Germany in the 1930s. This photograph is believed to be made on the occasion of Herman Oberth's Kegelduese liquid rocket engine being certified as to performance during firing. From left to right are R. Nebel, Dr. Ritter, Mr. Baermueller, Kurt Heinish, Herman Oberth, Klaus Riedel, Wernher von Braun, and an unidentified person.

  7. von Willebrand factor propeptide: biology and clinical utility.

    PubMed

    Haberichter, Sandra L

    2015-10-01

    von Willebrand factor (VWF) is a large multimeric glycoprotein that mediates the attachment of platelets to damaged endothelium and also serves as the carrier protein for coagulation factor VIII (FVIII), protecting it from proteolytic degradation. Quantitative or qualitative defects in VWF result in von Willebrand disease (VWD), a common inherited bleeding disorder. VWF is synthesized with a very large propeptide (VWFpp) that is critical for intracellular processing of VWF. VWFpp actively participates in the process of VWF multimerization and is essential for trafficking of VWF to the regulated storage pathway. Mutations identified within VWFpp in VWD patients are associated with altered VWF structure and function. The assay of plasma VWFpp has clinical utility in assessing acute and chronic vascular perturbation associated with diseases such as thrombotic thrombocytopenic purpura, sepsis, and diabetes among others. VWFpp assay also has clear utility in the diagnosis of VWD subtypes, particularly in discriminating true type 3 subjects from type 1C (reduced plasma survival of VWF), which is clinically important and has implications for therapeutic treatment. PMID:26215113

  8. Die neue Kosmologie. Von Dunkelmaterie, GUTs und Superhaufen.

    NASA Astrophysics Data System (ADS)

    Cornell, J.

    This book is a German translation, by M. Röser, of the American original "Bubbles, voids, and bumps in time: the new cosmology", published 1989 (see 49.003.045). Contents: 1. Die Entdeckung des Weltalls: Eine Einleitung (A. P. Lightman). 2. Die Vermessung des Weltalls: Rotverschiebungen und Standardkerzen (R. P. Kirshner). 3. Die Kartierung des Weltalls: Scheiben und Blasen (M. J. Geller). 4. Die Bestimmung der Masse im Weltall: Dunkelmaterie und fehlende Masse (V. C. Rubin). 5. Der Beginn des Weltalls: Urknall und kosmische Inflation (A. H. Guth). 6. Die Ausweitung des Weltalls: Das Weltraumteleskop und Perspektiven für die nächsten 20 Jahre (J. E. Gunn).

  9. Genetics Home Reference: Von Hippel-Lindau syndrome

    MedlinePLUS

    ... genes are related to von Hippel-Lindau syndrome? Mutations in the VHL gene cause von Hippel-Lindau ... dividing too rapidly or in an uncontrolled way. Mutations in this gene prevent production of the VHL ...

  10. Dr. Wernher Von Braun with Dr. Christian Barnard.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Christian Barnard Tours Marshall Space Flight Center. Shown in Dr. Von Braun's office are (left to right): Dr. Ernst Sthulinger, a representative from General Electric, Dr. Wernher Von Braun, Dr. Christian Barnard, and Dr. Eberhard Rees.

  11. QUANTITATIVE MORPHOLOGY

    EPA Science Inventory

    Abstract: In toxicology, the role of quantitative assessment of brain morphology can be understood in the context of two types of treatment-related alterations. One type of alteration is specifically associated with treatment and is not observed in control animals. Measurement ...

  12. Quantitative Thinking.

    ERIC Educational Resources Information Center

    DuBridge, Lee A.

    An appeal for more research to determine how to educate children as effectively as possible is made. Mathematics teachers can readily examine the educational problems of today in their classrooms since learning progress in mathematics can easily be measured and evaluated. Since mathematics teachers have learned to think in quantitative terms and…

  13. On Quantitizing

    ERIC Educational Resources Information Center

    Sandelowski, Margarete; Voils, Corrine I.; Knafl, George

    2009-01-01

    "Quantitizing", commonly understood to refer to the numerical translation, transformation, or conversion of qualitative data, has become a staple of mixed methods research. Typically glossed are the foundational assumptions, judgments, and compromises involved in converting disparate data sets into each other and whether such conversions advance…

  14. Level-Set-Segmentierung von Rattenhirn MRTs

    NASA Astrophysics Data System (ADS)

    Eiben, Björn; Kunz, Dietmar; Pietrzyk, Uwe; Palm, Christoph

    In dieser Arbeit wird die Segmentierung von Gehirngewebe aus Kopfaufnahmen von Ratten mittels Level-Set-Methoden vorgeschlagen. Dazu wird ein zweidimensionaler, kontrastbasierter Ansatz zu einem dreidimensionalen, lokal an die Bildintensität adaptierten Segmentierer erweitert. Es wird gezeigt, dass mit diesem echten 3D-Ansatz die lokalen Bildstrukturen besser berücksichtigt werden können. Insbesondere Magnet-Resonanz-Tomographien (MRTs) mit globalen Helligkeitsgradienten, beispielsweise bedingt durch Oberfiächenspulen, können auf diese Weise zuverlässiger und ohne weitere Vorverarbeitungsschritte segmentiert werden. Die Leistungsfähigkeit des Algorithmus wird experimentell an Hand dreier Rattenhirn-MRTs demonstriert.

  15. Dr. Wernher Von Braun talkes with George Hardy.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    George Hardy of the Marshall Space Flight center's Astronautics Laboratory, talks with Dr. Wernher Von Braun (right), deputy associate administrator for planning. Dr. Von Braun was inspecting the mockup of the Saturn workshop during a visit to the Marshall Center. The visit coincided with the 10th anniversary celebration of the center of which Dr. Von Braun was director until March 1, 1970.

  16. Quantitative radiography

    SciTech Connect

    Logan, C.M.; Hernandez, J.M.; Devine, G.J.

    1991-02-01

    We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernable by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudocolor images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. Images are captured using DuPont NDT55 industrial x-ray film in Daypack{trademark} packages. X-ray cabinets are of custom design, with helium flight path and a filter wheel for positioning filters if desired. The cabinets contain baffles to reduce scattered radiation and are equipped with drawer for rapid load/unload of parts. Separate units with tungsten-anode or copper-anode tubes are available. The usual operating voltage is 15 to 35 kVp. Fixturing provides for rough part positioning and precise alignment with respect to the x-ray source. Areal density standards are placed at several locations on each film. In interpreting the image, we use the standards nearest the image of the part being quantified. Because of this, small variations in x-ray flux uniformity (heel effects) are unimportant. The usual standard is a step wedge of aluminum containing 13 steps. Films are permanently labeled by imaging a perforated metal numbering strip. Data such as part number, step wedge identification, etc. are read from barcode labels and transferred to a data base for later retrieval and use in quantifying the image.

  17. Dr. von Braun tours Manufacturing Engineering Laboratory

    NASA Technical Reports Server (NTRS)

    1961-01-01

    During his tenure as Director of the Marshall Space Flight Center (MSFC), Dr. von Braun enjoyed personally touring the Center's many space-related laboratories and facilities. This photo taken about 1961 shows him examining a test set up in the Center's Manufacturing Engineering Laboratory.

  18. Guido von Pirquet: Austrian pioneer of astronautics

    NASA Technical Reports Server (NTRS)

    Sykora, F.

    1977-01-01

    The works of Guido von Pirquet, Austrian pioneer of rocketry, were assessed. Major emphasis was given to Pirquet's calculation of the route to Venus which in fact was followed by the first Russian rocket to Venus. Of interest also is Pirquet's valuable construction of a space station and his analysis of interstellar space flight.

  19. Dr. Wernher Von Braun presents a certificate

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (left), director of the Marshall Space Flight Center, presents a humorous certificate to Major General Charles W. Eifler, commanding general of Redstone Arsenal, at the close of a farewell luncheon for the general prior to General Eifler moving to a new European duty station.

  20. Dr. von Braun Visits Huntsville Boys Club

    NASA Technical Reports Server (NTRS)

    1961-01-01

    Dr. von Braun, Director of Marshall Space Flight Center (MSFC) and chairman of this year's United Givers Fund (UGF) drive at MSFC, takes time out from the problems of sending a man to the Moon to talk baseball with 11-year-old Randy Smith at the Huntsville Boys Club.

  1. Entwicklung von Landnutzungsszenarien für landschaftsökologische Fragestellungen

    NASA Astrophysics Data System (ADS)

    Fritsch, Uta

    2002-04-01

    Die Landschaften Mitteleuropas sind das Resultat einer langwierigen Geschichte menschlicher Landnutzung mit ihren unterschiedlichen, z.T. konkurrierenden Nutzungsansprüchen. Durch eine überwiegend intensive Beanspruchung haben die direkten und indirekten Auswirkungen der Landnutzung in vielen Fällen zu Umweltproblemen geführt. Die Disziplin der Landschaftsökologie hat es sich zur Aufgabe gemacht, Konzepte für eine nachhaltige Nutzung der Landschaft zu entwickeln. Eine wichtige Fragestellung stellt dabei die Abschätzung der möglichen Folgen von Landnutzungsänderungen dar. Für die Analyse der relevanten Prozesse in der Landschaft werden häufig mathematische Modelle eingesetzt, welche es erlauben die Landschaft unter aktuellen Verhältnissen oder hinsichtlich veränderter Rahmenbedingungen zu untersuchen. Die hypothetische Änderung der Landnutzung, die als Landnutzungsszenario bezeichnet wird, verkörpert eine wesentliche Modifikation der Rahmenbedingungen, weil Landnutzung mageblich Einfluss auf die natürlichen Prozesse der Landschaft nimmt. Während die Antriebskräfte einer solchen Änderung überwiegend von sozio-ökonomischen und politischen Entscheidungen gesteuert werden, orientiert sich die exakte Verortung der Landnutzungsänderungen an den naturräumlichen Bedingungen und folgt z.T. erkennbaren Regeln. Anhand dieser Vorgaben ist es möglich, räumlich explizite Landnutzungsszenarien zu entwickeln, die als Eingangsdaten für die Modellierung verschiedener landschaftsökologischer Fragestellungen wie z.B. für die Untersuchung des Einflusses der Landnutzung auf den Wasserhaushalt, die Erosionsgefahr oder die Habitatqualität dienen können. Im Rahmen dieser Dissertation wurde das rasterbasierte deterministische Allokationsmodell luck (Land Use Change Scenario Kit) für die explizite Verortung der Landnutzungsänderungen entwickelt. Es basiert auf den in der Landschaftsökologie üblichen räumlichen Daten wie Landnutzung, Boden sowie Topographie und richtet sich bei der Szenarienableitung nach den Leitbildern der Landschaftsplanung. Das Modell fut auf der Hypothese, dass das Landnutzungsmuster als Funktion seiner landschaftsökologischen Faktoren beschrieben werden kann. Das Veränderungspotenzial einer Landnutzungseinheit resultiert im Modell aus einer Kombination der Bewertung der relativen Eignung des Standortes für die jeweilige Landnutzung und der Berücksichtigung von Standorteigenschaften der umliegenden Nachbarn. Die Durchführung der Landnutzungsänderung im Modell ist iterativ angelegt, um den graduellen Prozess des Landschaftswandels nachvollziehen zu können. Als Fallbeispiel für die Anwendung solcher räumlich expliziten Landnutzungsszenarien dient die Fragestellung, inwieweit Landnutzungsänderungen die Hochwasserentstehung beeinflussen. Um den Einfluss auf die Hochwasserentstehung für jede der Landnutzungskategorien – bebaute, landwirtschaftlich genutzte und naturnahe Flächen – abschätzen zu können, wird im Landnutzungsmodell luck exemplarisch für jede Kategorie ein Teilmodell für die Veränderung von Landnutzung angeboten: 1) Ausdehnung der Siedlungsfläche: Dieses Teilmodell fut auf der Annahme, dass sich Siedlungen nur in direkter Nachbarschaft bereits bestehender Bebauung und bevorzugt entlang von Entwicklungsachsen ausbreiten. Steile Hangneigungen stellen für potenzielle Standorte ein Hemmnis bei der Ausbreitung dar. 2) Stilllegung von Grenzertragsackerflächen: Gemä der Hypothese, dass sich die Stilllegung von Ackerflächen an der potenziellen Ertragsleistung der Standorte orientiert, werden in diesem Teilmodell alle Ackerstandorte dahingehend bewertet und die Flächen mit der geringsten Leistungsfähigkeit stillgelegt. Bei homogenen Gebietseigenschaften werden die Stilllegungsflächen zufällig auf die Ackerfläche verteilt. 3) Etablierung von Schutzgebieten in Ufer- und Auenbereichen: Ausgehend von der These, dass sich entlang von Flüssen sensible Flächen befinden, deren Schutz positive Folgen für das Leistungsvermögen der Landschaft haben kann, w

  2. From the classical to the generalized von Karman and Marguerre-von Karman equations

    NASA Astrophysics Data System (ADS)

    Ciarlet, Philippe G.; Gratie, Liliana

    2006-06-01

    In this work, we describe and analyze two models that were recently proposed for modeling generalized von Karman plates and generalized Marguerre-von Karman shallow shells.First, we briefly review the "classical" von Karman and Marguerre-von Karman equations, their physical meaning, and their mathematical justification. We then consider the more general situation where only a portion of the lateral face of a nonlinearly elastic plate or shallow shell is subjected to boundary conditions of von Karman type, while the remaining portion is free. Using techniques from formal asymptotic analysis, we obtain in each case a two-dimensional boundary value problem that is analogous to, but is more general than, the classical equations.In particular, it is remarkable that the boundary conditions for the Airy function can still be determined on the entire boundary of the nonlinearly elastic plate or shallow shell solely from the data.Following recent joint works, we then reduce these more general equations to a single "cubic" operator equation, which generalizes an equation introduced by Berger and Fife, and whose sole unknown is the vertical displacement of the shell. We next adapt an elegant compactness method due to Lions for establishing the existence of a solution to this operator equation.

  3. The von Nardroff Color Mixing Apparatus

    NASA Astrophysics Data System (ADS)

    Greenslade, Thomas B.

    2005-12-01

    Ernest von Nardroff gave his name to the color mixing apparatus shown in Fig. 1. The basic idea behind this demonstration is to produce three beams of colored light that may be projected onto a white surface. If beams of red, blue, and green are overlapped to produce a figure like a three leaf clover or a Venn diagram, the region of complete overlap will appear white, and the three regions of overlap of two colors produce the three false primaries: yellow, magenta, and cyan. A straightforward technique is to use three slide projectors, each with a colored filter. Von Nardroff's apparatus, displayed at the educational exhibit of Erasmus Hall High School at the Louisiana Purchase Exposition in St. Louis in 1904, permits the use of only one projector.

  4. Virchow's triad: Kussmaul, Quincke and von Recklinghausen.

    PubMed

    Stanifer, John W

    2016-02-01

    For most of the 19th century, Germany was the centre of the medical world. From there the most innovating research came and many of the physicians of that era are known to nearly every medical student and physician of today. Virchow, Kussmaul, Quincke, von Recklinghausen, Müller and Schönlein are familiar names in today's medicine but insofar as they are merely eponyms associated with signs, symptoms, disease and anatomy. The story of their lives, their research and their influence on each other has been little examined. This is an essay about Virchow's relationship with his mentors Müller and Schönlein and how these relationships shaped the development of Kussmaul, Quincke and von Recklinghausen as students of Virchow and their work in medicine and clinical observation after leaving Virchow's laboratory. PMID:24658214

  5. A history of von Recklinghausen's NF1.

    PubMed

    Brosius, Stephanie

    2010-10-01

    While the study of genetic diseases is a rather recent development in science, von Recklinghausen's neurofibromatosis (NF1) has a rich pictorial history, seemingly dating back to the thirteenth century. In 1768, Akenside published a scientifically-based description of NF1, recognizing that the monsters of scholars, such as Parè and Aldrovandi, in fact suffered from a disorder of the nerves. The neuromas of NF1 were first detailed by Smith in 1849, but Frederick von Recklinghausen is credited with its discovery and coined the name of the disorder in 1882. NF1 research widely increased between 1909 and 1990, due to the erroneous diagnosis of the Elephant Man, Joseph Merrick. PMID:20938857

  6. [Duodenal somatostatinomas associated with von Recklinghausen disease].

    PubMed

    Blaser, A; Vajda, P; Rosset, P

    1998-12-12

    A case of von Recklinghausen's disease with double somatostatin producing neuroendocrine tumour of the ampulla and duodenum is reported. A search of the world's literature revealed 28 patients with immunohistologically proven duodenal somatostatinoma associated with type I neurofibromatosis. These tumours are seldom associated with a recognizable "somatostatin syndrome", but often present with obstructive jaundice, duodenal obstruction, weight loss or gastrointestinal bleeding. Histologically, psammoma bodies are frequently encountered in the glandular lumina of duodenal somatostatinomas (66%), whereas their presence in other neuroendocrine tumours of the gastrointestinal tract is very rare. Metastatization is rare (27%) and mainly confined to lymph nodes (88%). In the world literature duodenal somatostatinoma is associated with von Recklinghausen's disease in 50%. PMID:9888169

  7. Herstellung von Chitosan und einige Anwendungen

    NASA Astrophysics Data System (ADS)

    Struszczyk, Marcin Henryk

    2001-05-01

    1. Die Deacetylierung von crabshell - Chitosan führte gleichzeitig zu einem drastischen Abfall der mittleren viscosimetrischen Molmasse ( Mv), insbesondere wenn die Temperatur und die Konzentration an NaOH erhöht werden. Diese Parameter beeinflussten jedoch nicht den Grad der Deacetylierung (DD). Wichtig ist jedoch die Quelle des Ausgangsmaterials: Chitin aus Pandalus borealis ist ein guter Rohstoff für die Herstellung von Chitosan mit niedrigem DD und gleichzeitig hoher mittlerer Mv, während Krill-Chitin (Euphausia superba) ein gutes Ausgangsmaterial zur Herstellung von Chitosan mit hohem DD und niedrigem Mv ist. Chitosan, das aus Insekten (Calliphora erythrocephala), unter milden Bedingungen (Temperatur: 100°C, NaOH-Konzentration: 40 %, Zeit: 1-2h ) hergestellt wurde, hatte die gleichen Eigenschaften hinsichtlich DD und Mv wie das aus Krill hergestellte Chitosan. Der Bedarf an Zeit, Energie und NaOH ist für die Herstellung von Insekten-Chitosan geringer als für crabshell-Chitosan vergleichbare Resultaten für DD und Mv. 2. Chitosan wurde durch den Schimmelpilz Aspergillus fumigatus zu Chitooligomeren fermentiert. Die Ausbeute beträgt 25%. Die Chitooligomere wurden mit Hilfe von HPLC und MALDI-TOF-Massenspektrmetrie identifiziert. Die Fermentationsmischung fördert die Immunität von Pflanzen gegen Bakterien und Virusinfektion. Die Zunahme der Immunität schwankt jedoch je nach System Pflanze-Pathogen. Die Fermentation von Chitosan durch Aspergillus fumigatus könnte eine schnelle und billige Methode zur Herstellung von Chitooligomeren mit guter Reinheit und Ausbeute sein. Eine partiell aufgereinigte Fermentationsmischung dieser Art könnte in der Landwirtschaft als Pathogeninhibitor genutzt werden. Durch kontrollierte Fermentation, die Chitooligomere in definierter Zusammensetzung (d.h. definierter Verteilung des Depolymerisationsgrades) liefert, könnte man zu Mischungen kommen, die für die jeweilige Anwendung eine optimale Bioaktivität besitzen. 3. Die aus Chitosan-Dispersionen hergestellten MCChB-Filme weisen bessere mechanische Eigenschaften (Bruchfestigkeit, Dehnung) und eine höhere Wasseraufnahmefähigkeit auf als Filme, die nach herkömmlichen Methoden aus sauerer Lösung hergestellt werden. Die Einführung von Proteinen ändert die mechanischen Eigenschaften der MCChB-Filme abhängig von der Art, der Proteine sowie des DD und der Mv des eingesetzte Chitosan. Die Zugabe von Protein beschleunigt den biologischen Abbau der MCChB-Filme. Aus den untersuchten MCChB-Filmen mit Proteinzusatz können leichte, reißfeste und dennoch elastische Materialen hergestellt werden. 4. Mit Hilfe von MCChB-Dispersion kann Papier modifiziert werden. Dadurch werden die mechanischen Eigenschaften verbessert und die Wasseraufnahme wird verringert. Die Zugabe von Proteinen verringert das Wasseraufnahmevermögen noch weiter. Ein geringes Wasseraufnahmevermögen ist der bedeutendste Faktor bei der Papierherstellung. Auch Papier, das mit einem MCChB-Protein-Komplexe modifiziert wurde, zeigt gute mechanische Eigenschaften. 5. Wird Chitosan durch unmittelbare Einführung von MCChB auf Cellulose-Fasern aufgebracht, so erhält man eine netzartige Struktur, während durch Ausfällung aufgebrachtes Chitosan eine dünne Schicht auf den Cellulose-Fasern bildet. Die netzartige Struktur erleichtert die Bioabbaubarkeit, während die Schichtstruktur diese erschwert. 6. Die guten mechanischen Eigenschaften, die geringe Wasseraufnahmefähigkeit und die mit Cellulose vergleichbare Bioabbaubarkeit von Papier, das mit MCChB modifiziert wurde, lassen MCChB für die Veredlung von Papier nützlich erscheinen. 1. Deacetylation of the crustacean chitosan causes drastically decrease in the Mv with increasing reaction temperature and time as well as the concentration of sodium hydroxide. However, the DD are relatively less affected. Pandalus borealis is a good source for production of chitosan having high Mv and low DD, whereas chitosan of medium to low Mv can ideally be prepared using krill chitin. Insect chitosan is prepared under milder condition as compared with the crustacean chitosan, showed similar Mv and DD. Moreover, the consumption of time, energy and sodium hydroxide is much lower than for crustacean chitosan used. The properties of chitin (type of source, crystallinity, DD, Mv, swelling properties, particle size) affect the deacetylated polymer parameters. 2. Fermentation of chitosan using fungus Aspergillus fumigatus resulted in a composition of oligosaccharides with controlled molecular weight and yield at least 25 wt%. The product of fermentation effectively inhibited the viral and/or bacterial infection of the plant. This method can be an excellent, inexpensive system for preparation of bioactive agent. The preliminary purified fermentation mixture due to its antiviral and antibacterial behaviour is capable to be used as a natural, plant protection agent. The controlled degradation of chitosan connected with the production of various oligosaccharides having specified molecular weight allows obtaining the product with optimum bioactivity for suitable applications. 3. The films formed form microcrystalline chitosan (MCChB) gel-like dispersion demonstrate the better mechanical properties and higher swelling behaviour than typical films prepared using acidic solution of chitosan. The introduction of proteins significantly changes the mechanical strength and swelling behaviour. Addition of proteins causes the increase in their biodecomposition. The blended films containing proteins could be the base for formation of the resistant materials showed excellent elongation at break. 4. The application of MCChB in a paper formation as a modificator of the fibre-water interactions allows producing the paper sheets indicating the high increase in the mechanical properties and significant decrease in swelling properties. The introduction of MCChB with proteins causes a slight decrease in paper mechanical strength, if determined at low relative humidity. However, the mechanical strength measured at high relative humidity differ less than for paper sheet containing only MCChB. 5. Direct introduction of MCChB to a paper pulp forms the "web-like" structure of cellulose fibres and MCChB. The "web-like" structure of MCChB enables the faster biodecomposition of formed paper sheets. The precipitation of MCChB as wells as introduction of MCChB with proteins causes the "coat-like" structure. MCChB creates a thin layers coated the cellulose fibres lowering a biodecomposition rate. 6. The properties of paper sheets modified by MCChB such as: similar to cellulose biodegradation, excellent mechanical properties at rel. high humidity and the decrease in swelling properties as well as various possibilities to introduce MCChB allow to apple microcrystalline chitosan with or without proteins as the modificator of the fibre-water interactions in paper.

  8. On Koopman-von Neumann Waves

    NASA Astrophysics Data System (ADS)

    Mauro, D.

    In this paper we study the classical Hilbert space introduced by Koopman and von Neumann in their operatorial formulation of classical mechanics. In particular we show that the states of this Hilbert space do not spread, differently from what happens in quantum mechanics. The role of the phases associated to these classical ``wave functions'' is analyzed in detail. In this framework we also perform the analog of the two-slit interference experiment and compare it with the quantum case.

  9. Portrait of Dr. Von Braun with Walt Disney, 1954.

    NASA Technical Reports Server (NTRS)

    1954-01-01

    Marshall Center Director Dr. Wernher Von Braun is pictured with Walt Disney during a visit to the Marshall Space Flight Center in 1954. In the 1950s, Dr. Von Braun while working in California on the Saturn project, also worked with Disney studios as a technical director in making three films about Space Exploration for television. Disney's tour of Marshall in 1965 was Von Braun's hope for a renewed public interest in the future of the Space Program at NASA.

  10. Numerical study of impeller-driven von Kármán flows via a volume penalization method

    NASA Astrophysics Data System (ADS)

    Kreuzahler, S.; Schulz, D.; Homann, H.; Ponty, Y.; Grauer, R.

    2014-10-01

    Studying strongly turbulent flows is still a major challenge in fluid dynamics. It is highly desirable to have comparable experiments to obtain a better understanding of the mechanisms generating turbulence. The von Kármán flow apparatus is one of those experiments that has been used in various turbulence studies by different experimental groups over the last two decades. The von Kármán flow apparatus produces a highly turbulent flow inside a cylinder vessel driven by two counter-rotating impellers. The studies cover a broad range of physical systems including incompressible flows, especially water and air, magnetohydrodynamic systems using liquid metal for understanding the important topic of the dynamo instability, particle tracking to study Lagrangian type turbulence and recently quantum turbulence in super-fluid helium. Therefore, accompanying numerical studies of the von Kármán flow that compare quantitatively data with those from experiments are of high importance for understanding the mechanism producing the characteristic flow patterns. We present a direct numerical simulation (DNS) version the von Kármán flow, forced by two rotating impellers. The cylinder geometry and the rotating objects are modelled via a penalization method and implemented in a massive parallel pseudo-spectral Navier-Stokes solver. From the wide range of different impellers used in von Kármán water and sodium experiments we choose a special configuration (TM28), in order to compare our simulations with the according set of well documented water experiments. Though this configuration is different from the one in the final VKS experiment (TM73), using our method it is quite easy to change the impeller shape to the one actually used in VKS. The decomposition into poloidal and toroidal components and the mean velocity field from our simulations are in good agreement with experimental results. In addition, we analysed the flow structure close to the impeller blades, a region hardly accessible to experiments. Depending on the blade geometry different vortex topologies are found. The very promising results imply that our numerical modelling could also be applied to other physical systems and configurations driven by the von Kármán flow.

  11. Current therapy in children and adolescents with von Willebrand disease

    PubMed Central

    Buga-Corbu, I; Arion, C

    2014-01-01

    Abstract The article represents a review of recent data about the therapy of von Willebrand disease in children and adolescents (hereditary as well as acquired forms of the disease). The treatment of bleeding events in these patients, the indications in different subtypes, and the future lines of research are mentioned. Abbreviations: Ag VWF = von Willebrand antigen, VWD = von Willebrand disease, DDAVP = arginine-vasopressin, EACA = epsilon aminocaproic acid, VWF = von Willebrand factor, VIIc F = the VIIth factor of coagulation, VIIIc F = the VIIIth factor of coagulation, IgG = immunoglobulin G, T/2 = half-time, WVF – Rco = the ristocetin cofactor. PMID:25408737

  12. Ein Konzept für den energieeffizienten Betrieb von Mobilfunknetzen

    NASA Astrophysics Data System (ADS)

    Bayer, N.; von Hugo, D.

    2015-11-01

    Der flächendeckende Betrieb mehrerer Mobilfunknetze unterschiedlicher Technologie in einem Land sorgt aufgrund der ständigen Bereithaltung von Übertragungskapazität für Dienste mit zunehmend höherem Datenvolumenbedarf für einen erheblichen Energieverbrauch. Das Forschungsförderungsprojekt ComGreen hat sich zur Aufgabe gesetzt, durch lastadaptiven Betrieb und intelligente dynamische Rekonfiguration des Funkzugangsnetzes zur Energieeinsparung beizutragen. Konzept, Herausforderungen, ausgewählte Ergebnisse von Simulationen und prototypischem Betrieb werden ebenso wie typische Erwartungswerte des künftigen Energieverbrauchs im Mobilfunkbereich vorgestellt. Sowohl Berechnungen als auch Messungen zeigen, dass durch kontext-basierte dynamische Rekonfiguration von zellularen Funknetzen Energieeinsparungen im Bereich von 25-40 % ermöglicht werden.

  13. Tight junctions in Gerbil von Ebner's gland: horseradish peroxidase and freeze-fracture studies.

    PubMed

    Huang, Anthony Y; Chen, Ming-Huei; Wu, Sandy Y; Lu, Kuo-Shyan

    2015-03-01

    The permeability of tight junctions to horseradish peroxidase (HRP) and the freeze-fracture appearance of junctional structures were investigated in the von Ebner's gland of gerbils. In the tracing study, HRP was either administered topically on the dorsal surface of tongues or injected subepithelially into the connective tissue of vallate papillae for 5-30 min. Lingual tissues containing the von Ebner's gland were sectioned and examined by light and electron microscopy. In von Ebner's glands, the reaction product for HRP was found in the intercellular and interstitial spaces, whereas HRP appeared to penetrate the tight junctions and the reaction product was localized in the lumina of serous acini. In contrast, the staining for HRP that delineated the boundary of epithelial cells was frequently observed in the superficial layers of the lingual epithelium but not the underlying tissues while applying HRP topically. Freeze-fracture replicas of acinar cells revealed that the tight junction had a depth of 0.815?±?0.023 ?m, and 4-6 parallel strands on the protoplasmic fracture face, with a branching network of joining strands with interruptions, interconnections and high linear strand density apically, and corresponding grooves on the extracellular face. Quantitative analyses showed a greater number of strands (7.217?±?0.326) in gerbils compared to those of acinar cells (3.86?±?0.22) in mice. These results demonstrate that the tight junctions in the gerbil von Ebner's gland is permeable, and that specific species differences in tight junction structures may be associated with the mechanism for survival in an extremely dry environment. PMID:25639455

  14. On Koopman-Von Neumann Waves II

    NASA Astrophysics Data System (ADS)

    Gozzi, E.; Mauro, D.

    In this paper, we continue the study started in Ref. 1, of the operatorial formulation of classical mechanics given by Koopman and von Neumann (KvN) in the 1930s. In particular, we show that the introduction of the KvN Hilbert space of complex and square integrable "wave functions" requires an enlargement of the set of the observables of ordinary classical mechanics. The possible role and the meaning of these extra observables is briefly indicated in this work. We also analyze the similarities and differences between non-selective measurements and two-slit experiments in classical and quantum mechanics.

  15. Zur ethischen Dimension von Renaturierungsökologie und Ökosystemrenaturierung

    NASA Astrophysics Data System (ADS)

    Ott, Konrad

    Die wissenschaftlich angeleitete Ökosystemrena-turierung kann mittlerweile als eine etablierte Praxis im Bereich des Naturschutzes gelten. Diese Praxis bezieht sich notwendigerweise auf Ziele und Werte und weist damit auch eine naturethische Dimension auf. Daher hat diese Praxis die Aufmerksamkeit auch von Sozialwissenschaftlern und Ethikern auf sich gezogen. Dieses Kapitel geht der Frage nach, wie sich die naturethische Dimension der Ökosystemrenaturierung analysieren und inhaltlich bestimmen lässt. Hierzu erweist sich auch die Auseinandersetzung mit Philosophen als hilfreich, die der Ökosystemrenaturierung ein technizistisches Naturverständnis vorgeworfen haben. Am Ende des Kapitels wird ein in sich gestuftes mögliches naturethisches Selbstverständnis der Ökosystemrenaturierung diskutiert, das den an dieser Praxis Beteiligten Freiheitsgrade der Positionierung belässt.

  16. Key contributors: Ernst von Glasersfeld's radical constructivism

    NASA Astrophysics Data System (ADS)

    Tobin, Kenneth

    2007-07-01

    This article reviews the significance of the contributions of Ernst von Glasersfeld to research in science education, especially through his theoretical contributions on radical constructivism. As a field shaper, Glasersfeld's subversive ideas catalyzed debate in the science education community and fuelled transformation of many facets including research methods, ways of thinking about teaching and learning, curriculum, and science teacher education. Perturbations emanating from the debates on constructivism forged new pathways that led to the development and use of many of the sociocultural frameworks employed by authors in Cultural Studies of Science Education.

  17. Approximating incompatible von Neumann measurements simultaneously

    SciTech Connect

    Heinosaari, Teiko; Jivulescu, Maria Anastasia; Reitzner, Daniel; Ziman, Mario

    2010-09-15

    We study the problem of performing orthogonal qubit measurements simultaneously. Since these measurements are incompatible, one has to accept additional imprecision. An optimal joint measurement is the one with the least possible imprecision. All earlier considerations of this problem have concerned only joint measurability of observables, while in this work we also take into account conditional state transformations (i.e., instruments). We characterize the optimal joint instrument for two orthogonal von Neumann instruments as being the Lueders instrument of the optimal joint observable.

  18. Acquired von Willebrand syndrome: von Willebrand factor propeptide to von Willebrand factor antigen ratio predicts remission status

    PubMed Central

    Lee, Adrienne; Sinclair, Gary; Valentine, Karen; James, Paula

    2014-01-01

    We investigated a case of acquired von Willebrand syndrome (AVWS) secondary to a nonneutralizing anti-von Willebrand factor (VWF) antibody associated with an autoimmune disorder. At diagnosis, VWF activity (VWF:Act), antigen (VWF:Ag), multimers, and factor VIII coagulant activity were virtually absent. VWF propeptide (VWFpp) was elevated with an infinitely high VWFpp to VWF:Ag ratio (VWFpp:Ag) consistent with rapid VWF clearance. Immunosuppressive treatment resulted in phenotypic remission 1 with normalization of VWF/factor VIII levels and multimer pattern. However, VWFpp:Ag remained elevated (?2× normal), consistent with ongoing VWF clearance by the remaining anti-VWF antibody still present by enzyme-linked immunosorbent assay. This suggests that increased VWF secretion was compensating for the incomplete remission state. Relapse occurred when VWFpp:Ag was again infinitely high, with associated decreased VWFpp but unchanged anti-VWF titers; switching the balance to favor VWF clearance over secretion. Complete remission with undetectable anti-VWF occurred only when VWFpp:Ag was normal. This case of relapsing-remitting AVWS demonstrates the use of VWFpp:Ag for predicting remission status. PMID:24951428

  19. Dr. von Braun Tries Out the Neutral Buoyancy Simulator (NBS)

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Marshall Space Flight Center (MSFC) Director, Dr. von Braun, is shown leaving the suiting-up van wearing a pressure suit prepared for a tryout in the MSFC Neutral Buoyancy Simulator (NBS). Weighted to a neutrally buoyant condition, Dr. von Braun was able to perform tasks underwater which simulated weightless conditions found in space.

  20. Dr. von Braun Tries Out the Neutral Buoyancy Simulator (NBS)

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Astronaut L. Gordon Cooper checks the neck ring of a space suit worn by Marshall Space Flight Center (MSFC) Director, Dr. von Braun before he submerges into the water of the MSFC Neutral Buoyancy Simulator (NBS). Wearing a pressurized suit and weighted to a neutrally buoyant condition, Dr. von Braun was able to perform tasks underwater which simulated weightless conditions found in space.

  1. Dr. von Braun Tries Out the Neutral Buoyancy Simulator (NBS)

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Marshall Space Flight Center (MSFC) Director, Dr. von Braun, submerges after spending some time under water in the MSFC Neutral Buoyancy Simulator (NBS). Weighted to a neutrally buoyant condition, Dr. von Braun was able to perform tasks underwater which simulated weightless conditions found in space.

  2. Die Entwicklung von Proto-Gasplaneten mit Drehimpuls. Strahlungshydrodynamische Rechnungen.

    NASA Astrophysics Data System (ADS)

    Götz, M.

    1993-04-01

    In dieser Arbeit wurde die Entstehung der Gasplaneten im Rahmen der kerninduzierten Gasinstabilitätshypothese betrachtet. Es wurden numerische strahlungshydrodynamische Modellreihen für die Struktur der Hülle eines Protoplaneten im Abstand Jupiters von der Sonne erstellt. Erstmals wurde hierbei der Einfluß von Drehimpuls in der quasisphärischen Näherung berücksichtigt.

  3. Victor or Villain? Wernher von Braun and the Space Race

    ERIC Educational Resources Information Center

    O'Brien, Jason L.; Sears, Christine E.

    2011-01-01

    Set during the Cold War and space race, this historical role-play focuses on Wernher von Braun's involvement in and culpability for the use of slave laborers to produce V-2 rockets for Nazi Germany. Students will grapple with two central questions. Should von Braun have been allowed to emigrate to the United States given his affiliation with the…

  4. Group Theoretical Interpretation of von Neumann's Theorem on Composite Systems.

    ERIC Educational Resources Information Center

    Bergia, S.; And Others

    1979-01-01

    Shows that von Neumann's mathematical theorem on composite systems acquires a transparent physical meaning with reference to a suitable physical example; a composite system in a state of definite angular momentum. Gives an outline of the theorem, and the results are restated in Dirac's notation, thus generalizing von Neumann's results which were…

  5. Victor or Villain? Wernher von Braun and the Space Race

    ERIC Educational Resources Information Center

    O'Brien, Jason L.; Sears, Christine E.

    2011-01-01

    Set during the Cold War and space race, this historical role-play focuses on Wernher von Braun's involvement in and culpability for the use of slave laborers to produce V-2 rockets for Nazi Germany. Students will grapple with two central questions. Should von Braun have been allowed to emigrate to the United States given his affiliation with the…

  6. Relative von Neumann entropy for evaluating amino acid conservation.

    PubMed

    Johansson, Fredrik; Toh, Hiroyuki

    2010-10-01

    The Shannon entropy is a common way of measuring conservation of sites in multiple sequence alignments, and has also been extended with the relative Shannon entropy to account for background frequencies. The von Neumann entropy is another extension of the Shannon entropy, adapted from quantum mechanics in order to account for amino acid similarities. However, there is yet no relative von Neumann entropy defined for sequence analysis. We introduce a new definition of the von Neumann entropy for use in sequence analysis, which we found to perform better than the previous definition. We also introduce the relative von Neumann entropy and a way of parametrizing this in order to obtain the Shannon entropy, the relative Shannon entropy and the von Neumann entropy at special parameter values. We performed an exhaustive search of this parameter space and found better predictions of catalytic sites compared to any of the previously used entropies. PMID:20981889

  7. Arg578Gln mutations in the von Willebrand factor gene in three unrelated cases of type IIB von Willebrand disease.

    PubMed

    Piao, Y C; Lavergne, J M; Boyer-Neumann, C; Schandelong, A; Alessi, M C; Meyer, D

    1993-10-01

    A recurrent heterozygous CGG-->CAG (Arg578Gln) mutation was detected in exon 28 of the von Willebrand factor gene in three additional unrelated families with inherited type IIB von Willebrand disease. This identical mutation showed a differential phenotypic expression in each family. PMID:8292729

  8. Superfluid high REynolds von Kármán experiment

    NASA Astrophysics Data System (ADS)

    Rousset, B.; Bonnay, P.; Diribarne, P.; Girard, A.; Poncet, J. M.; Herbert, E.; Salort, J.; Baudet, C.; Castaing, B.; Chevillard, L.; Daviaud, F.; Dubrulle, B.; Gagne, Y.; Gibert, M.; Hébral, B.; Lehner, Th.; Roche, P.-E.; Saint-Michel, B.; Bon Mardion, M.

    2014-10-01

    The Superfluid High REynolds von Kármán experiment facility exploits the capacities of a high cooling power refrigerator (400 W at 1.8 K) for a large dimension von Kármán flow (inner diameter 0.78 m), which can work with gaseous or subcooled liquid (He-I or He-II) from room temperature down to 1.6 K. The flow is produced between two counter-rotating or co-rotating disks. The large size of the experiment allows exploration of ultra high Reynolds numbers based on Taylor microscale and rms velocity [S. B. Pope, Turbulent Flows (Cambridge University Press, 2000)] (R? > 10000) or resolution of the dissipative scale for lower Re. This article presents the design and first performance of this apparatus. Measurements carried out in the first runs of the facility address the global flow behavior: calorimetric measurement of the dissipation, torque and velocity measurements on the two turbines. Moreover first local measurements (micro-Pitot, hot wire,…) have been installed and are presented.

  9. Approximate von Neumann entropy for directed graphs

    NASA Astrophysics Data System (ADS)

    Ye, Cheng; Wilson, Richard C.; Comin, César H.; Costa, Luciano da F.; Hancock, Edwin R.

    2014-05-01

    In this paper, we develop an entropy measure for assessing the structural complexity of directed graphs. Although there are many existing alternative measures for quantifying the structural properties of undirected graphs, there are relatively few corresponding measures for directed graphs. To fill this gap in the literature, we explore an alternative technique that is applicable to directed graphs. We commence by using Chung's generalization of the Laplacian of a directed graph to extend the computation of von Neumann entropy from undirected to directed graphs. We provide a simplified form of the entropy which can be expressed in terms of simple node in-degree and out-degree statistics. Moreover, we find approximate forms of the von Neumann entropy that apply to both weakly and strongly directed graphs, and that can be used to characterize network structure. We illustrate the usefulness of these simplified entropy forms defined in this paper on both artificial and real-world data sets, including structures from protein databases and high energy physics theory citation networks.

  10. Treatment of patients with von Willebrand disease

    PubMed Central

    Tuohy, Emma; Litt, Emma; Alikhan, Raza

    2011-01-01

    Von Willebrand disease (vWD) is the most common hereditary bleeding disorder. The aim of therapy is to correct the dual hemostatic defect, due to defective platelet adhesion-aggregation and abnormal coagulation due to Factor VIII (FVIII) deficiency. The choice of treatment depends on a number of factors, including the severity of the bleed, the procedure planned, the subtype and severity of the disease and the age and morbidity of the patient. Desmopressin (DDAVP) is the treatment of choice for type 1 vWD as it increases endogenous release of FVIII and von Willebrand factor (vWF) and is also used in some subtypes of type 2 vWD. In those patients in whom DDAVP is ineffective or contraindicated, levels can be restored by infusing vWF:FVIII concentrates. The role of antifibrinolytic treatment is an important adjunct to replacement therapy during minor or major surgery involving mucosal surfaces. The dosing and timing of vWF:FVIII concentrates is important depending on the nature of the surgical procedure. The role of secondary prophylaxis needs to be further defined. PMID:22287863

  11. Inattentional blindness and the von Restorff effect.

    PubMed

    Schmidt, Stephen R; Schmidt, Constance R

    2015-02-01

    Sometimes we fail to notice distinctive or unusual items (inattentional blindness), while other times we remember distinctive items more than expected items (the von Restorff effect). A three-factor framework is presented and tested in two experiments in an attempt to reconcile these seemingly contradictory phenomena. Memory for different types of unexpected stimuli was tested after an easy or difficult Stroop color-naming task. Highly arousing taboo words were well remembered even when the difficult Stroop task limited attentional resources. However, a conceptual isolation effect was only observed when the nature of the category change was highlighted by the Stroop task, the Stroop task was easy, and/or the isolated targets enjoyed a retrieval advantage relative to comparison targets. As proposed in the three-factor framework, the arousing qualities of the stimuli, the attentional demands of the primary task, and the relevance of isolated features at encoding and retrieval combine to produce inattentional blindness and the von Restorff effect. PMID:25169672

  12. Superfluid high REynolds von Kármán experiment.

    PubMed

    Rousset, B; Bonnay, P; Diribarne, P; Girard, A; Poncet, J M; Herbert, E; Salort, J; Baudet, C; Castaing, B; Chevillard, L; Daviaud, F; Dubrulle, B; Gagne, Y; Gibert, M; Hébral, B; Lehner, Th; Roche, P-E; Saint-Michel, B; Bon Mardion, M

    2014-10-01

    The Superfluid High REynolds von Kármán experiment facility exploits the capacities of a high cooling power refrigerator (400 W at 1.8 K) for a large dimension von Kármán flow (inner diameter 0.78 m), which can work with gaseous or subcooled liquid (He-I or He-II) from room temperature down to 1.6 K. The flow is produced between two counter-rotating or co-rotating disks. The large size of the experiment allows exploration of ultra high Reynolds numbers based on Taylor microscale and rms velocity [S. B. Pope, Turbulent Flows (Cambridge University Press, 2000)] (R? > 10000) or resolution of the dissipative scale for lower Re. This article presents the design and first performance of this apparatus. Measurements carried out in the first runs of the facility address the global flow behavior: calorimetric measurement of the dissipation, torque and velocity measurements on the two turbines. Moreover first local measurements (micro-Pitot, hot wire,…) have been installed and are presented. PMID:25362417

  13. Interactions of von Willebrand factor and ADAMTS13 in von Willebrand disease and thrombotic thrombocytopenic purpura.

    PubMed

    Budde, U; Schneppenheim, R

    2014-01-01

    The function of von Willebrand factor (VWF), a huge multimeric protein and a key factor in platelet dependent primary haemostasis, is regulated by its specific protease ADAMTS13. The ADAMTS13 dependent degradation of VWF to its proteolytic fragments can be visualized as a characteristic so-called triplet structure of individual VWF oligomers by multimer analysis. Lack of VWF high molecular weight multimers (VWF-HMWM) or their pathologically enhanced degradation underlies a particular type of von Willebrand disease, VWD type 2A with a significant bleeding tendency, and may also be observed in acquired von Willebrand syndrome due to cardiovascular disease. In these conditions multimer analysis is an obligatory and powerful tool for diagnosis of VWD. The opposite condition, the persistence of ultralarge VWF (UL-VWF) multimers may cause the microangiopathic life-threatening disorder thrombotic thrombocytopenic purpura (TTP). During the course of active TTP, UL-VWF is consumed in the hyaline thrombi formed in the microvasculature which will ultimately result in the loss of UL-VWF and VWF-HMWM. Therefore, VWF multimer analysis is not a valid tool to diagnose TTP in the active phase of disease but may be helpful for the diagnosis of TTP patients in remission. PMID:25010251

  14. Automatische Lokalisation und hämodynamische Charakterisierung von Gefäßstrukturen bei arteriovenösen Malformationen

    NASA Astrophysics Data System (ADS)

    Forkert, Nils Daniel; Säring, Dennis; Fiehler, Jens; Illies, Till; Handels, Heinz

    Im Beitrag werden Verfahren zur automatischen Detektion des Kerns der Arteriovenösen Malformation (AVM) sowie der zuleitenden (Feeder), ableitenden (Drainagevenen) und en passge" Blutgef äße präsentiert. Als Eingabe hierfür dienen hochaufgelöste 3D- sowie zeitlich-räumliche 4D-MRT-Bildsequenzen. Durch eine kombinierte Analyse der Intensität, der Geschwindigkeit und des relativen Einflusszeitpunktes des Blutes werden Gefäßstrukturen automatisch charakterisiert. Die vorgestellte Methode zur Detektion des Kerns wurde anhand von manuellen Segmentierungen validiert und ergab eine mittlere Volumen- übereinstimmung von ca. 88%. Drainagevenen und Feeder konnten mit einer Genauigkeit von 95% detektiert werden.

  15. A von Bertalanffy growth model with a seasonally varying coefficient

    USGS Publications Warehouse

    Cloern, James E.; Nichols, Frederic H.

    1978-01-01

    The von Bertalanffy model of body growth is inappropriate for organisms whose growth is restricted to a seasonal period because it assumes that growth rate is invariant with time. Incorporation of a time-varying coefficient significantly improves the capability of the von Bertalanffy equation to describe changing body size of both the bivalve mollusc Macoma balthicain San Francisco Bay and the flathead sole, Hippoglossoides elassodon, in Washington state. This simple modification of the von Bertalanffy model should offer improved predictions of body growth for a variety of other aquatic animals.

  16. Inertial Manifolds for von Karman Plate Equations

    SciTech Connect

    Chueshov, I. Lasiecka, I.

    2002-12-19

    Inertial manifolds associated with nonlinear plate models governed by dynamical von Karman equations are considered. Three different dissipative mechanisms are discussed: viscous, structural and thermal damping. Though the systems considered are subject to some dissipation, the overall dynamics may not be dissipative. This means that the energy may not be decreasing. The main result of the paper establishes the existence of an inertial manifold subject to the spectral gap condition for linearized problems. The validity of the spectral gap condition depends on the geometry of the domain and the type of damping. It is shown that the spectral gap condition holds for plates of rectangular shape. In the case of viscous damping, which is associated with hyperbolic-like dynamics, it is also required that the damping parameter be sufficiently large. This last requirement is not needed for other types of dissipation considered in the paper.

  17. Hermann von Helmholtz and his students

    NASA Astrophysics Data System (ADS)

    Mulligan, Joseph F.

    1989-01-01

    During the years 1871-1888, when Hermann von Helmholtz was professor of physics at the University of Berlin, physicists from all over the world flocked to Berlin to study and do research with him. Among these were the German physicists Max Planck, Heinrich Kayser, Eugen Goldstein, Wilhelm Wien, and Heinrich Hertz, and Americans Henry Rowland, A. A. Michelson, and Michael Pupin. Examples of Helmholtz's scientific and personal interactions with these students and research associates show why he is justly considered the outstanding physics mentor of the 19th century. Both his ideas and his students played a major role in the development of physics in the late 19th and early 20th centuries.

  18. Echtzeiterkennung von befahrbaren Bereichen in urbanen Szenarien

    NASA Astrophysics Data System (ADS)

    Berger, Kai; Linz, Christian; Lipski, Christian; Stich, Timo; Magnor, Marcus

    Unser Artikel beschreibt em Echtzeitverfahren zur kamerabasicrten Fahrbereichserkennung, welches in urbanen bzw. ländlichen Fahrszenarien eingesetzt wird. In dem Eingabebild eines monokularen Kamerasystems, weiches auf dem Dach eines Automobils in Fahrtrichtung montiert ist, wird pro Zeitschritt ein kleiner Bereich vor der Motorhaube als befahrbar vorausgesetzt. Der Algorithmus berechnet die vorherrschenden Farben innerhalb dieses befahrbaren Bereiches und vergleicht die Farben mit den Farbwerten jedes Pixels im Eingabebild: Je ähnlicher die Pixelfarben zu den vorherrschenden sind, desto hölier ist die Wahrscheinlichkeit, dass die entsprechenden Bereiche befahrbar sind. Um den Algorithmus auch im städtischen Umfeld einsetzen zu können, muss ein vorverarbeitendes Modul vorgeschaltet werden, welches Fahrspuren, Schatten und überberbelichtete Bereiche ausmaskiert und in der entgültigen Befahrbarkeitskarte als unbekannt (rot) markiert. Weiterhin wird em dynamisches Suchpolygon vorgestellt, um den Algorithmus unabhängig von weiteren Eingabesensoren zu gestalten.

  19. Biochemical specificity of von Economo neurons in hominoids

    PubMed Central

    Stimpson, Cheryl D.; Tetreault, Nicole A.; Allman, John M.; Jacobs, Bob; Butti, Camilla; Hof, Patrick R.; Sherwood, Chet C.

    2010-01-01

    Von Economo neurons (VENs) are defined by their thin, elongated cell body and long dendrites projecting from apical and basal ends. These distinctive neurons are mostly present in anterior cingulate (ACC) and fronto-insular (FI) cortex, with particularly high densities in cetaceans, elephants, and hominoid primates (i.e., humans and apes). This distribution suggests that VENs contribute to specializations of neural circuits in species that share both large brain size and complex social cognition, possibly representing an adaptation to rapidly relay socially-relevant information over long distances across the brain. Recent evidence indicates that unique patterns of protein expression may also characterize VENs, particularly involving molecules that are known to regulate gut and immune function. In this study, we used quantitative stereologic methods to examine the expression of three such proteins that are localized in VENs – activating-transcription factor 3 (ATF3), interleukin 4 receptor (IL4R?) and neuromedin B (NMB). We quantified immunoreactivity against these proteins in different morphological classes of ACC layer V neurons of hominoids. Among the different neuron types analyzed (pyramidal, VEN, fork, enveloping, and other multipolar), VENs showed the greatest percentage that displayed immunostaining. Additionally, a higher proportion of VENs in humans were immunoreactive to ATF3, IL4R?, and NMB than in other apes. No other ACC layer V neuron type displayed a significant species difference in the percentage of immunoreactive neurons. These findings demonstrate that phylogenetic variation exists in the protein expression profile of VENs, suggesting that humans might have evolved biochemical specializations for enhanced interoceptive sensitivity. PMID:21140465

  20. Quantum theory and geometry: sixty years after von Neumann

    NASA Astrophysics Data System (ADS)

    Varadarajan, V. S.

    1993-10-01

    This paper is a brief review of some of the developments in the mathematical foundations of quantum mechanics that have taken place since the publication in 1932 of John von Neumann's celebrated treatise Mathematische Grundlagen der Quantenmechanik.

  1. 61. VON BRAUN BLOCKHOUSE (BUILDING 1592): VIEW FROM SOUTHWEST, WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. VON BRAUN BLOCKHOUSE (BUILDING 1592): VIEW FROM SOUTHWEST, WITH MILL BUILDING IN BACKGROUND - White Sands Missile Range, V-2 Rocket Facilities, Near Headquarters Area, White Sands, Dona Ana County, NM

  2. 7. Historic American Buildings Survey, Charles Von Urban, Photographer June ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey, Charles Von Urban, Photographer June 23, 1936, INTERIOR-PARLOR SHOWING FIREPLACE, WINDOWN TRIM, AND CORNICE. - George Fordham House, 329 Cherry Street, New York, New York County, NY

  3. 2. Historic American Buildings Survey, Charles Von Urban, Photographer June ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey, Charles Von Urban, Photographer June 23, 1936, DETAIL OF ENTRANCE STEPS AND AREA RAILING. - George Fordham House, 329 Cherry Street, New York, New York County, NY

  4. Dr. Wernher Von Braun examines a ruby crystal.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Wernher Von Braun (right), director of the Marshall Space Flight Center, and Dr. Eberhard Rees (left), deputy director, technical, examine a ruby crystal used in laser experiments in the Marshall Center's Space Sciences Laboratory.

  5. 33. HISTORIC VIEW OF WERNHER VON BRAUN LOOKS THROUGH THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. HISTORIC VIEW OF WERNHER VON BRAUN LOOKS THROUGH THE PERISCOPE FROM THE CONTROL ROOM AT TEST STAND NO. 1, PEENEMUENDE. - Marshall Space Flight Center, Redstone Rocket (Missile) Test Stand, Dodd Road, Huntsville, Madison County, AL

  6. A proof of von Neumann's postulate in Quantum Mechanics

    SciTech Connect

    Conte, Elio

    2010-05-04

    A Clifford algebraic analysis is explained. It gives proof of von Neumann's postulate on quantum measurement. It is of basic significance to explain the problem of quantum wave function reduction in quantum mechanics.

  7. Alexander von Humboldt and the Origins of Landscape Archaeology.

    ERIC Educational Resources Information Center

    Mathewson, Kent

    1986-01-01

    Reviews the life, theories, and influence of Alexander von Humboldt, the early nineteenth century founder of modern geography. Maintains that Humboldt's novel approaches to the study of landscape antiquities have value for contemporary students in cultural and historical geography. (JDH)

  8. Wernher von Braun with German Officers and Others

    NASA Technical Reports Server (NTRS)

    1942-01-01

    General Erich Fellgiebel, head of the German Army Information Service during World War II, congratulates members of the von Braun rocket team from Peenemunde for their October 3, 1942 A4 flight. Pictured front center is General Erich Fellgiebel. Shaking hands are General Walter Dornberger (left) and General Janssen, commanding officer of Peenemuende with Rudolph Hermarn to their right. Picture left to right in the back row are Wernher von Braun, Captain Stoelzel, Luftwaffe, and Dr. Gerhard Reisig.

  9. Physik gestern und heute Von der Metallstange zum Hochenergielaser

    NASA Astrophysics Data System (ADS)

    Heering, Peter

    2002-05-01

    Im Mai 1752 wurde in Marly bei Paris auf Anregung des amerikanischen Forschers und Politikers Benjamin Franklin erstmals die elektrische Natur des Blitzes nachgewiesen. Damals beschrieb Franklin auch eine technische Vorrichtung, die als Schutz von Gebäuden vor Blitzschlägen dienen sollte: den Blitzableiter. Diese aus heutiger Sicht scheinbar triviale Vorrichtung wurde aber keineswegs unmittelbar akzeptiert. Und bis heute ist die Forschung zum Schutz von Einrichtungen vor Blitzschlägen nicht abgeschlossen.

  10. Evidence-based recommendations on the treatment of von Willebrand disease in Italy

    PubMed Central

    Mannucci, Pier Mannuccio; Franchini, Massimo; Castaman, Giancarlo; Federici, Augusto B.

    2009-01-01

    Background von Willebrand disease (VWD) is the most common hereditary bleeding disorder affecting both males and females. It arises from quantitative or qualitative defects of von Willebrand factor (VWF) and causes bleeding of mucous membranes and soft tissues. The aim of treatment is to correct the dual defect of haemostasis caused by the abnormal/reduced VWF and the concomitant deficiency of factor VIII (FVIII). Material and methods This document contains evidence-based recommendations for the management of VWD compiled by AICE (the Italian Association of Haemophilia Centres). All the evidence supporting these recommendations are based on non-randomised comparative studies or case series, because randomised controlled clinical trials or meta-analyses are not available for this disease. Results and conclusions Desmopressin (DDAVP) is the treatment of choice for patients with type 1 VWD with FVIII and VWF levels of 10 U/dL or more, while VWF/FVIII concentrates are indicated for those who are unresponsive or insufficiently responsive to DDAVP (severe type 1, type 2 and 3 VWD). VWF concentrates devoid of FVIII, not yet licensed in Italy, may be considered for short-term prophylaxis in elective surgery or for long-term secondary prophylaxis. PMID:19503633

  11. Characterization of Zebrafish von Willebrand Factor Reveals Conservation of Domain Structure, Multimerization, and Intracellular Storage

    PubMed Central

    Ghosh, Arunima; Vo, Andy; Twiss, Beverly K.; Kretz, Colin A.; Jozwiak, Mary A.; Montgomery, Robert R.; Shavit, Jordan A.

    2012-01-01

    von Willebrand disease (VWD) is the most common inherited human bleeding disorder and is caused by quantitative or qualitative defects in von Willebrand factor (VWF). VWF is a secreted glycoprotein that circulates as large multimers. While reduced VWF is associated with bleeding, elevations in overall level or multimer size are implicated in thrombosis. The zebrafish is a powerful genetic model in which the hemostatic system is well conserved with mammals. The ability of this organism to generate thousands of offspring and its optical transparency make it unique and complementary to mammalian models of hemostasis. Previously, partial clones of zebrafish vwf have been identified, and some functional conservation has been demonstrated. In this paper we clone the complete zebrafish vwf cDNA and show that there is conservation of domain structure. Recombinant zebrafish Vwf forms large multimers and pseudo-Weibel-Palade bodies (WPBs) in cell culture. Larval expression is in the pharyngeal arches, yolk sac, and intestinal epithelium. These results provide a foundation for continued study of zebrafish Vwf that may further our understanding of the mechanisms of VWD. PMID:23049555

  12. Unexpected reemergence of the von Neumann theorem

    NASA Astrophysics Data System (ADS)

    Żukowski, Marek

    2009-02-01

    It is shown here that the “simple test of quantumness for a single system” of Alicki and Van Ryn has exactly the same relation to the discussion of the problem of describing the quantum system via a classical probabilistic scheme (that is in terms of hidden variables or within a realistic theory) as the von Neumann theorem [Mathematische Grundlagen der Quantenmechanik (Springer, Berlin, 1932); Mathematical Foundations of Quantum Mechanics (Princeton University, Princeton, NJ, 1955)]. The latter one was shown by Bell [Rev. Mod. Phys. 38, 447 (1966)] to stem from an assumption that the hidden variable values for a sum of two noncommuting observables have to be, for each individual system, equal to sums of eigenvalues of the two operators. One cannot find a justification for such an assumption to hold for noncommeasurable variables. On the positive side, the criterion may be useful in rejecting models which are based on stochastic classical fields. Nevertheless, the example used by the authors has a classical optical realization.

  13. [Carl Friedrich von Weizsäcker - physicist and philosopher].

    PubMed

    Drieschner, Michael

    2014-01-01

    The subject of this paper is the philosopher Carl Friedrich von weizsäcker, especially under the aspect of the relation between physics and philosophy in his works. The decisive role of time in physics as well as in philosophy is described, and thereof is derived the comprehension of probability as a predicted relative frequency. Consequently quantum mechanics is interpreted as a theory of probability that uses "quantum logic" instead of classical propositional logic that is used in "normal" probability. The philosophical fruit of that is the interpretation of potentiality as the modality of the future. Weizsäcker's proposals for a justification of physics a priori are dealt with as well as his approach to a theory of "ur-objects", which are atoms in the strictest sense: q-bits.--Questions of Weizsäcker's personality are addressed: His role in the development of the nuclear reactor and atomic bomb in Nazi time, his enthusiasm and his religiousness as well as his efforts towards world peace. PMID:24974618

  14. Periodontal manifestations of von Recklinghausen neuro fibromatosis.

    PubMed

    Shetty, Bhavya; Umesh, Y; Kranti, K; Seshan, Hema

    2013-03-01

    Neurofibroma is an uncommon benign tumor of the oral cavity derived from the cells that constitute the nerve sheath neurofibromatosis type 1 (NF1), also known as von Recklinghausen's disease, is the most common type of neurofibromatosis and accounts for about 90% of all cases. It is one of the most frequent human genetic diseases, with the prevalence of one case in 3,000 births. Neurofibroma is seen either as a solitary lesion or as part of the generalized syndrome of neurofibromatosis. The solitary form does not differ from the disseminated form or the multiple form of the disease, except that systemic and hereditary factors present in the disseminated form are absent in the solitary type. Oral cavity involvement by a solitary and peripheral plexiform neurofibroma in patients with no other signs of neurofibromatosis is uncommon. The expressivity of NF1 is extremely variable, with manifestations ranging from mild lesions to several complications and functional impairment. Oral manifestations can be found in almost 72% of NF1 patients. This is a case report of a 40-year-old lady with a history of multiple faint rounded densities in the skin, chest pain occasionally since 8 months and breathlessness since 1 year and swelling of the right side of the angle of the mandible with limited mouth opening. PMID:23869137

  15. von Neumann spin measurements with Rashba fields

    NASA Astrophysics Data System (ADS)

    Sherman, E. Ya; Sokolovski, D.

    2014-01-01

    We show that dynamics in the spin-orbit coupling field simulate the von Neumann measurement of a particle spin. We demonstrate how the measurement influences the spin and coordinate evolution of a particle by comparing two examples of such a procedure. The first example is a simultaneous measurement of spin components, σx and σy, corresponding to non-commuting operators, which cannot be accurately obtained together at a given time instant due to the Heisenberg uncertainty ratio. By mapping spin dynamics onto a spatial walk, such a procedure determines measurement-time averages of σx and σy, which can already be precisely evaluated in a single short-time measurement. The other, qualitatively different, example is the spin of a one-dimensional particle in a magnetic field. Here, the measurement outcome depends on the angle between the spin-orbit coupling and magnetic fields. These results can be applied to studies of spin-orbit coupled cold atoms and electrons in solids.

  16. Locally Compact Quantum Groups. A von Neumann Algebra Approach

    NASA Astrophysics Data System (ADS)

    Van Daele, Alfons

    2014-08-01

    In this paper, we give an alternative approach to the theory of locally compact quantum groups, as developed by Kustermans and Vaes. We start with a von Neumann algebra and a comultiplication on this von Neumann algebra. We assume that there exist faithful left and right Haar weights. Then we develop the theory within this von Neumann algebra setting. In [Math. Scand. 92 (2003), 68-92] locally compact quantum groups are also studied in the von Neumann algebraic context. This approach is independent of the original C^*-algebraic approach in the sense that the earlier results are not used. However, this paper is not really independent because for many proofs, the reader is referred to the original paper where the C^*-version is developed. In this paper, we give a completely self-contained approach. Moreover, at various points, we do things differently. We have a different treatment of the antipode. It is similar to the original treatment in [Ann. Sci. & #201;cole Norm. Sup. (4) 33 (2000), 837-934]. But together with the fact that we work in the von Neumann algebra framework, it allows us to use an idea from [Rev. Roumaine Math. Pures Appl. 21 (1976), 1411-1449] to obtain the uniqueness of the Haar weights in an early stage. We take advantage of this fact when deriving the other main results in the theory. We also give a slightly different approach to duality. Finally, we collect, in a systematic way, several important formulas. In an appendix, we indicate very briefly how the C^*-approach and the von Neumann algebra approach eventually yield the same objects. The passage from the von Neumann algebra setting to the C^*-algebra setting is more or less standard. For the other direction, we use a new method. It is based on the observation that the Haar weights on the C^*-algebra extend to weights on the double dual with central support and that all these supports are the same. Of course, we get the von Neumann algebra by cutting down the double dual with this unique support projection in the center. All together, we see that there are many advantages when we develop the theory of locally compact quantum groups in the von Neumann algebra framework, rather than in the C^*-algebra framework. It is not only simpler, the theory of weights on von Neumann algebras is better known and one needs very little to go from the C^*-algebras to the von Neumann algebras. Moreover, in many cases when constructing examples, the von Neumann algebra with the coproduct is constructed from the very beginning and the Haar weights are constructed as weights on this von Neumann algebra (using left Hilbert algebra theory). This paper is written in a concise way. In many cases, only indications for the proofs of the results are given. This information should be enough to see that these results are correct. We will give more details in forthcoming paper, which will be expository, aimed at non-specialists. See also [Bull. Kerala Math. Assoc. (2005), 153-177] for an 'expanded' version of the appendix.

  17. Die Wirtschaftliche Bedeutung von Cyberphysical Systems aus der Sicht Eines Global Players

    NASA Astrophysics Data System (ADS)

    Beetz, Klaus

    Langfristiges und nachhaltiges Denken ist ein wichtiger Teil unserer Tradition. Nachhaltigkeit heißt für uns, in unseren Handlungen die Belange von Ökologie, Ökonomie und sozialer Verantwortung ausgewogen zu berücksichtigen.", sagte Peter Löscher, CEO von Siemens, im Januar 2010.

  18. An Alternative to Von Glasersfeld's Subjectivism in Science Education: Deweyan Social Constructivism.

    ERIC Educational Resources Information Center

    Garrison, Jim

    1997-01-01

    Discusses von Glasersfeld's view of constructivism in science and mathematics educational research and practice. Provides a social constructivist alternative to von Glaserfeld's subjectivist constructivism. Discusses the practical art of experimental construction and objectivity in science education. (Author/JRH)

  19. Changes in von Willebrand factor level and von Willebrand activity with age in type 1 von Willebrand disease

    PubMed Central

    Rydz, Natalia; Grabell, Julie; Lillicrap, David; James, Paula D.

    2015-01-01

    In a normal population, VWF plasma levels (VWF:Ag) and VWF activity (VWF:RCo) increase by approximately 0.17 and 0.15 IU/ml per decade, but the influence of age is unknown in patients with type 1 von Willebrand disease (VWD). In a retrospective cohort study, the medical records of 31 type 1 VWD patients over the age of 30, who had been followed for ?5 years, were reviewed for baseline clinical data and previously performed VWF:Ag, VWF:RCo and factor VIII levels (FVIII:C). VWF multimer analysis was normal in 27/31 cases performed. Mean bleeding score was 9.4 (range 2-21). Mean age at diagnosis was 33 (range 16-60 years), and duration of follow-up ranged from 5-26 years (mean 11 years). Patients had 2-10 time points of VWD testing (mean of 5.2). The mean VWF:Ag, VWF:RCo and FVIII:C at time of diagnosis were 0.44 IU/ml 0.34 IU/ml and 0.75 IU/ml. At last follow-up, the mean VWF:Ag, VWF:RCo and FVIII:C were significantly increased to 0.71 IU/L, 0.56 IU/ml and 0.90 IU/ml (p=<0.001, <0.001, and 0.0081, respectively). 18/31 patients had VWF:Ag, VWF:RCo and FVIII:C levels that increased into the normal range. The rate of change in VWF:Ag and VWF:RCo was 0.30 IU/ml (0.214-0.386, CI 95%, p<0.0001) and 0.20 IU/ml per year (0.126-0.274, CI 95%, p=0.0001). Patients with type 1 VWD experience age-related increases to VWF:Ag and VWF:RCo which can result in normalization of VWF levels. Further studies are required to determine if the bleeding phenotype resolves with the increases in VWF:Ag and VWF:RCo levels. PMID:25756206

  20. Kohärenz in linearen Anordungen von Josephsonverbindungen mit induktiver Kopplung

    NASA Astrophysics Data System (ADS)

    Krech, W.

    Mit Hilfe von verkürzten Gleichungen für die Phasen der Spannungsoszillationen untersuchen wir das Synchronisationsverhalten einer linearen Anordnung von Josephsonverbindungen mit induktiver Kopplung. Als Beispiele dienen die Kopplung zwischen nächsten Nachbarn, die Kopplung großer Reichweite und die SQUID-Kopplung. Wir betrachten insbesondere die Ausprägung von kohärenten Moden und deren Stabilitätsverhalten, den Effekt der Gleichstromleitfähigkeit auf das phase-locking and die Toleranz der kritischen Ströme der Josephsonverbindungen.Translated AbstractCoherence in Linear Arrays of Josephson Junctions with Inductive CouplingUsing reduced equations for the phases of the voltage oscillations we investigate the synchronization in a linear array of Josephson junctions with inductive coupling. The examples under consideration are the coupling between next neighbours, the large range coupling and the SQUID coupling. Especially, we investigate the formation of coherent modes and their stability, the effect of the de conductivity on the phase locking and the tolerance of the junctions critical currents.

  1. Gamma Stability in Free Product von Neumann Algebras

    NASA Astrophysics Data System (ADS)

    Houdayer, Cyril

    2015-06-01

    Let be a free product of arbitrary von Neumann algebras endowed with faithful normal states. Assume that the centralizer is diffuse. We first show that any intermediate subalgebra which has nontrivial central sequences in M is necessarily equal to M 1. Then we obtain a general structural result for all the intermediate subalgebras with expectation. We deduce that any diffuse amenable von Neumann algebra can be concretely realized as a maximal amenable subalgebra with expectation inside a full nonamenable type III1 factor. This provides the first class of concrete maximal amenable subalgebras in the framework of type III factors. We finally strengthen all these results in the case of tracial free product von Neumann algebras.

  2. Gunther von Hagens' BODY WORLDS: selling beautiful education.

    PubMed

    Burns, Lawrence

    2007-04-01

    In the BODY WORLDS exhibitions currently touring the United States, Gunther von Hagens displays human cadavers preserved through plastination. Whole bodies are playfully posed and exposed to educate the public. However, the educational aims are ambiguous, and some aspects of the exhibit violate human dignity. In particular, the signature cards attached to the whole-body plastinates that bear the title, the signature of Gunther von Hagens, and the date of creation mark the plastinates as artwork and von Hagens as the artist in a gesture that strips the personal dignity from the donors. I conclude that the educational use of cadavers is compatible with respect for dignity if: 1) the utility of such use is great enough; 2) there are no other ways of achieving these ends; and 3) every effort is made to honor the dignity of the donors. PMID:17454986

  3. Anwendung von Methoden der Logistik und Netzplantechnik zur präzedenz- und ressourcenbeschränkten Ablaufplanung von Echtzeitsystemen

    NASA Astrophysics Data System (ADS)

    Gumzej, Roman; Lipi?nik, Martin

    Grundlegende Zusammenhänge zwischen Logistik, Netzplantechnik und Echtzeit sowie den zugehörigen Arten der Ablaufplanung und ihrer Nutzung werden dargestellt. Das Echtzeitprinzip beinhaltet Rechtzeitigkeit von Abläufen, wobei es für eine frühzeitige Beendigung eines Ablaufs keinen Bonus gibt; im Gegensatz zum verspäteten Ablauf, dessen Konsequenzen in der Regel negativ und unabschätzbar sind. Das Just-in-Time-Prinzip gleicht dem der Echtzeit und wird vor allem in der Logistik zur Bezeichnung reibungsloser Abläufe in Beschaffungsketten verwendet. In der Netzplantechnik werden die kritischen Aktivitäten binnen eines Projektes bestimmt, die nicht verzögert werden dürfen, um das Projekt rechtzeitig zu beenden. Außerdem haben die drei Bereiche noch eine Gemeinsamkeit: um realistische Ablaufszenarien darzustellen, müssen in den Analysen auch begrenzte Ressourcen angemessen berücksichtigt werden.

  4. Pulmonary hypertension and von Recklinghausen's disease: association and therapeutic difficulties.

    PubMed

    Ennibi, K; El Kassimi, I; Asfalou, I; Chaari, J; Benyass, A

    2015-01-01

    The neurofibromatosis type 1 (NF1) or Von Recklinghausen's disease is a genetic disorder. The café-au-lait spots and neurofibromas are the most common manifestations. Respiratory symptoms are rare in this disease, described as neurofibromas, infiltrative lesions, cysts, bubbles or emphysema. Pulmonary hypertension is rarely reported. It is due to the plexiform lesions in pulmonary arterioles or to parenchymal lung lesions reducing the vascular bed. We report a case of idiopathic precapillary pulmonary hypertension in a young patient with Von Recklinghausen's disease. PMID:26738373

  5. An Accurate von Neumann's Law for Three-Dimensional Foams

    SciTech Connect

    Hilgenfeldt, Sascha; Kraynik, Andrew M.; Koehler, Stephan A.; Stone, Howard A.

    2001-03-19

    The diffusive coarsening of 2D soap froths is governed by von Neumann's law. A statistical version of this law for dry 3D foams has long been conjectured. A new derivation, based on a theorem by Minkowski, yields an explicit analytical von Neumann's law in 3D which is in very good agreement with detailed simulations and experiments. The average growth rate of a bubble with F faces is shown to be proportional to F{sup 1/2} for large F , in contrast to the conjectured linear dependence. Accounting for foam disorder in the model further improves the agreement with data.

  6. Henry Cavendish, Johann von Soldner, and the deflection of light

    NASA Astrophysics Data System (ADS)

    Will, Clifford M.

    1988-05-01

    The gravitational deflection of light based on Newtonian theory and the corpuscular model of light was calculated, but never published, around 1784 by Henry Cavendish, almost 20 years earlier than the first published calculation by Johann Georg von Soldner. The two results are slightly different because, while Cavendish treated a light ray emitted from infinity, von Soldner treated a light ray emitted from the surface of the gravitating body. At the first order of approximation, they agree with each other; both are one-half the value predicted by general relativity and confirmed by experiment.

  7. The smooth entropy formalism for von Neumann algebras

    NASA Astrophysics Data System (ADS)

    Berta, Mario; Furrer, Fabian; Scholz, Volkher B.

    2016-01-01

    We discuss information-theoretic concepts on infinite-dimensional quantum systems. In particular, we lift the smooth entropy formalism as introduced by Renner and collaborators for finite-dimensional systems to von Neumann algebras. For the smooth conditional min- and max-entropy, we recover similar characterizing properties and information-theoretic operational interpretations as in the finite-dimensional case. We generalize the entropic uncertainty relation with quantum side information of Tomamichel and Renner and discuss applications to quantum cryptography. In particular, we prove the possibility to perform privacy amplification and classical data compression with quantum side information modeled by a von Neumann algebra.

  8. Non-von Recklinghausen's neurofibromatosis resembling a giant pigmented nevus.

    PubMed

    Bousema, M T; Vuzevski, V D; Oranje, A P; Heule, F; Stolz, E; van Joost, T

    1989-02-01

    We report the case of a 30-year-old female patient with non-von Recklinghausen's neurofibromatosis. In our opinion it does not fit within a system of classification recently described. Clinically, the abnormality resembled a giant pigmented nevus; however, light- and electron microscopy findings were consistent with those of a neurofibroma. No other symptoms of classic neurofibromatosis or other diseases were present. The family history showed no evidence of neurofibromatosis. To the best of our knowledge this manifestation of non-von Recklinghausen's neurofibromatosis has not been previously described. The cause and the inheritance pattern of this variant are not clear. PMID:2492569

  9. Quantitative nuclear hepatology

    SciTech Connect

    Gilbert, S.A.; Brown, P.H.; Krishnamurthy, G.T.

    1987-03-01

    This is the first in a series of four Continuing Education articles on quantitative imaging techniques. After studying this article, the reader should be able to: 1) compare the radiopharmaceuticals available for hepatobiliary imaging; 2) discuss quantitation of hepatobiliary studies; and 3) discuss the clinical applications of these techniques.

  10. Quantitative plant proteomics.

    PubMed

    Bindschedler, Laurence V; Cramer, Rainer

    2011-02-01

    Quantitation is an inherent requirement in comparative proteomics and there is no exception to this for plant proteomics. Quantitative proteomics has high demands on the experimental workflow, requiring a thorough design and often a complex multi-step structure. It has to include sufficient numbers of biological and technical replicates and methods that are able to facilitate a quantitative signal read-out. Quantitative plant proteomics in particular poses many additional challenges but because of the nature of plants it also offers some potential advantages. In general, analysis of plants has been less prominent in proteomics. Low protein concentration, difficulties in protein extraction, genome multiploidy, high Rubisco abundance in green tissue, and an absence of well-annotated and completed genome sequences are some of the main challenges in plant proteomics. However, the latter is now changing with several genomes emerging for model plants and crops such as potato, tomato, soybean, rice, maize and barley. This review discusses the current status in quantitative plant proteomics (MS-based and non-MS-based) and its challenges and potentials. Both relative and absolute quantitation methods in plant proteomics from DIGE to MS-based analysis after isotope labeling and label-free quantitation are described and illustrated by published studies. In particular, we describe plant-specific quantitative methods such as metabolic labeling methods that can take full advantage of plant metabolism and culture practices, and discuss other potential advantages and challenges that may arise from the unique properties of plants. PMID:21246733

  11. Dr. von Braun With a Model of a Launch Vehicle

    NASA Technical Reports Server (NTRS)

    1950-01-01

    Dr. von Braun stands beside a model of the upper stage (Earth-returnable stage) of the three-stage launch vehicle built for the series of the motion picture productions of space flight produced by Walt Disney in the mid-1950's.

  12. Dr. Wernher Von Braun near the mobile launcher.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. George Mueller, NASA associate administrator for manned space flight, and Dr. Wernher Von Braun (right), director of the Marshall Space Flight Center, are seen near the mobile launcher carrying a 363 foot tall Saturn V space launch vehicle as the rocket is rolled from the vehicle assembly building at KSC for its three mile trip to the launch pad.

  13. Wilhelm von Humboldt's Idea of "Bildung" and Education.

    ERIC Educational Resources Information Center

    Stubbs, Elsina

    The importance of Wilhelm von Humboldt's work in educational philosophy is little known outside of Germany and even there he is more often criticized than praised. This is unfortunate because his contributions to education and other areas had an important impact on other philosophers of his period and are well worth considering today. In his main…

  14. Ernst von Glasersfeld's Radical Constructivism and Truth as Disclosure

    ERIC Educational Resources Information Center

    Joldersma, Clarence W.

    2011-01-01

    In this essay Clarence Joldersma explores radical constructivism through the work of its most well-known advocate, Ernst von Glasersfeld, who combines a sophisticated philosophical discussion of knowledge and truth with educational practices. Joldersma uses Joseph Rouse's work in philosophy of science to criticize the antirealism inherent in…

  15. Dr. Wernher Von Braun with Congressman Gerald R. fod

    NASA Technical Reports Server (NTRS)

    1999-01-01

    On a visit to the Marshall Space Flight Center in April, 1964, Congressman Gerald R. Ford, Jr. Republican of Michigan, was warmly greeted by Dr. Wernher Von Braun, Marshall Space Flight Center director. Ford, along with two other congressmen, visited the center for a briefing on the Saturn program and for a tour of the facilities.

  16. Treasure in the Library Attic: Von Ranke at Syracuse.

    ERIC Educational Resources Information Center

    Coville, Bruce

    1984-01-01

    Traces history of private library of German scholar, Leopold von Ranke, which was purchased by Syracuse University in 1888. Efforts of librarian Charles W. Bennett in 1870s and Professor James Powell beginning in late 1960s, and restoration and cataloging of collection are highlighted. Items from the collection are noted. (EJS)

  17. Ernst von Glasersfeld's Radical Constructivism and Truth as Disclosure

    ERIC Educational Resources Information Center

    Joldersma, Clarence W.

    2011-01-01

    In this essay Clarence Joldersma explores radical constructivism through the work of its most well-known advocate, Ernst von Glasersfeld, who combines a sophisticated philosophical discussion of knowledge and truth with educational practices. Joldersma uses Joseph Rouse's work in philosophy of science to criticize the antirealism inherent in…

  18. Wernher von Braun: Reflections on His Contributions to Space Exploration

    NASA Technical Reports Server (NTRS)

    Goldman, Arthur E.

    2012-01-01

    In 1950, Dr. Wernher von Braun and approximately 100 of his team members came to Huntsville, Alabama, to begin work with the Army on what would later become America's historic space program. He would later serve as the first director of the Marshall Space Flight Center and led the development of the Saturn V launch vehicle that launched seven crewed American mission to the moon, as well as America s first space station, Skylab. Von Braun is best known for his team s technical achievements. He realized his dream of exploring outer space by helping place humans on the moon. His engineering and managerial talent during the Apollo era had contributed to a technological revolution. He was by all accounts a good engineer, but he was only one among many. What set Von Braun apart were his charisma, his vision, and his leadership skills. He inspired loyalty and dedication in the people around him. He understood the importance of communicating his vision to his team, to political and business leaders and the public. Today, the Marshall Center continues his vision by pursuing engineering and scientific projects that will continue to open space to exploration. This presentation will discuss Von Braun's impact on Huntsville, the Marshall Center, the nation and the world and look at his contributions in context of where world space exploration is today.

  19. Primary carcinoma of the lung in von Recklinghausen neurofibromatosis.

    PubMed

    Gupta, K B; Kumar, Vipul; Tandon, Sanjeev; Gill, Meenu

    2009-10-01

    von Recklinghausen neurofibromatosis (NF-1) is the most common inherited syndrome predisposing to neoplasia, particularly neural crest-derived tumors. However, lung malignancies reported in association with neurofibromatosis are sparse. We present a case of a 48-year-old man with NF-1 that manifested as carcinoma of lung, in order to discuss the linkage between these two entities. PMID:20531996

  20. Mol-Gastronomie Von Weihnachtsplätzchen und anderen granularen Backwerken

    NASA Astrophysics Data System (ADS)

    Vilgis, Thomas

    2003-11-01

    Weihnachten steht vor der Tür, und aus den Backöfen duften die ersten Plätzchen als Vorboten. Die isst man auch bei Physikers so gern, dass kaum ein Krumen übrig bleibt. Dabei sind die Krümel besonders interessant, denn sie zeigen eine Vielzahl von Merkmalen und lassen auf die verschiedenen Teigarten schließen, deren Reiz nicht nur im Geschmack, sondern auch in Herstellungsweise und Teigklasse liegt.

  1. [Clinical and fluorescein angiographic aspects in retinal angiomatosis (von Hippel)].

    PubMed

    Samoil?, O; C?lug?ru, D; C?lug?ru, M

    2007-01-01

    Retinal angiomas represent a rare condition consisting of hamartomas isolated or associated with a systemic disease (Von Hippel-Lindau Disease). We present a patient with multiple retinal angiomas, with atypical fluorescein angiography possible due to vascular thrombotic phenomena. Visual acuity was slightly diminished because of hemorrhagic complications. Systemic involvement was excluded with imaging studies. PMID:17937036

  2. Freiheit als Substanz - Metaphysische Aspekte von Initialemergenz und kosmischer Evolution.

    NASA Astrophysics Data System (ADS)

    Zimmermann, R. E.

    Der Autor konzentriert sich auf den expliziten Vermittlungszusammenhang von initialer Emergenz und kosmischer Evolution. Dabei zeigt er Möglichkeiten für eine Neuformulierung modern gefaßter Substanz-Metaphysik auf, an den neueren Ergebnissen der Naturwissenschaft orientiert und auf die unterstellte Ganzheit alles Welthaften gestützt.

  3. Hemostatic efficacy, safety, and pharmacokinetics of a recombinant von Willebrand factor in severe von Willebrand disease.

    PubMed

    Gill, Joan C; Castaman, Giancarlo; Windyga, Jerzy; Kouides, Peter; Ragni, Margaret; Leebeek, Frank W G; Obermann-Slupetzky, Ortrun; Chapman, Miranda; Fritsch, Sandor; Pavlova, Borislava G; Presch, Isabella; Ewenstein, Bruce

    2015-10-22

    This phase 3 trial evaluated the safety and hemostatic efficacy of a recombinant von Willebrand factor (rVWF) for treatment of bleeds in severe von Willebrand disease (VWD). rVWF was initially administered together with recombinant factor VIII (rFVIII) and subsequently alone, as long as hemostatic factor VIII activity (FVIII : C) levels were maintained. Pharmacokinetics (PK) were evaluated in a randomized cross-over design (rVWF vs rVWF:rFVIII at 50 IU VWF:ristocetin cofactor activity [RCo]/kg). Bleed control for all treated bleeds (N = 192 bleeds in 22 subjects) was rated good or excellent (96.9% excellent; 119 of 122 minor, 59 of 61 moderate, and 6 of 7 major bleeds) on a 4-point scale (4 = none to 1 = excellent). A single infusion was effective in 81.8% of bleeds. Treatment success, defined as the number of subjects with a mean efficacy rating of <2.5, was 100%. The PK profile of rVWF was not influenced by rFVIII (mean VWF:RCo terminal half-life: 21.9 hours for rVWF and 19.6 hours for rVWF:rFVIII). FVIII : C levels increased rapidly after rVWF alone, with hemostatic levels achieved within 6 hours and sustained through 72 hours after infusion. Eight adverse events (AEs; 6 nonserious AEs in 4 subjects and 2 serious AEs [chest discomfort and increased heart rate, without cardiac symptomatology] concurrently in 1 subject) were associated with rVWF. There were no thrombotic events or severe allergic reactions. No VWF or FVIII inhibitors, anti-VWF binding antibodies, or antibodies against host cell proteins were detected. These results show that rVWF was safe and effective in treating bleeds in VWD patients and stabilizes endogenous FVIII : C, which may eliminate the need for rFVIII after the first infusion. This trial was registered at www.clinicaltrials.gov as #NCT01410227. PMID:26239086

  4. Hemostatic efficacy, safety, and pharmacokinetics of a recombinant von Willebrand factor in severe von Willebrand disease

    PubMed Central

    Gill, Joan C.; Castaman, Giancarlo; Windyga, Jerzy; Kouides, Peter; Ragni, Margaret; Leebeek, Frank W. G.; Obermann-Slupetzky, Ortrun; Chapman, Miranda; Fritsch, Sandor; Pavlova, Borislava G.; Presch, Isabella

    2015-01-01

    This phase 3 trial evaluated the safety and hemostatic efficacy of a recombinant von Willebrand factor (rVWF) for treatment of bleeds in severe von Willebrand disease (VWD). rVWF was initially administered together with recombinant factor VIII (rFVIII) and subsequently alone, as long as hemostatic factor VIII activity (FVIII:C) levels were maintained. Pharmacokinetics (PK) were evaluated in a randomized cross-over design (rVWF vs rVWF:rFVIII at 50 IU VWF:ristocetin cofactor activity [RCo]/kg). Bleed control for all treated bleeds (N = 192 bleeds in 22 subjects) was rated good or excellent (96.9% excellent; 119 of 122 minor, 59 of 61 moderate, and 6 of 7 major bleeds) on a 4-point scale (4 = none to 1 = excellent). A single infusion was effective in 81.8% of bleeds. Treatment success, defined as the number of subjects with a mean efficacy rating of <2.5, was 100%. The PK profile of rVWF was not influenced by rFVIII (mean VWF:RCo terminal half-life: 21.9 hours for rVWF and 19.6 hours for rVWF:rFVIII). FVIII:C levels increased rapidly after rVWF alone, with hemostatic levels achieved within 6 hours and sustained through 72 hours after infusion. Eight adverse events (AEs; 6 nonserious AEs in 4 subjects and 2 serious AEs [chest discomfort and increased heart rate, without cardiac symptomatology] concurrently in 1 subject) were associated with rVWF. There were no thrombotic events or severe allergic reactions. No VWF or FVIII inhibitors, anti-VWF binding antibodies, or antibodies against host cell proteins were detected. These results show that rVWF was safe and effective in treating bleeds in VWD patients and stabilizes endogenous FVIII:C, which may eliminate the need for rFVIII after the first infusion. This trial was registered at www.clinicaltrials.gov as #NCT01410227. PMID:26239086

  5. HCG blood test - quantitative

    MedlinePLUS

    A quantitative human chorionic gonadotropin (HCG) test measures the specific level of HCG in the blood. HCG is a hormone produced in the body during pregnancy. Other HCG tests include: HCG urine test HCG blood test - qualitative

  6. On Quantitative Rorschach Scales.

    ERIC Educational Resources Information Center

    Haggard, Ernest A.

    1978-01-01

    Two types of quantitative Rorschach scales are discussed: first, those based on the response categories of content, location, and the determinants, and second, global scales based on the subject's responses to all ten stimulus cards. (Author/JKS)

  7. Quantitative film radiography

    SciTech Connect

    Devine, G.; Dobie, D.; Fugina, J.; Hernandez, J.; Logan, C.; Mohr, P.; Moss, R.; Schumacher, B.; Updike, E.; Weirup, D.

    1991-02-26

    We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernible by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudo-color images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. This report discusses: the method; film processor monitoring and control; verifying film and processor performance; and correction of scatter effects.

  8. Quantitative receptor autoradiography

    SciTech Connect

    Boast, C.A.; Snowhill, E.W.; Altar, C.A.

    1986-01-01

    Quantitative receptor autoradiography addresses the topic of technical and scientific advances in the sphere of quantitative autoradiography. The volume opens with a overview of the field from a historical and critical perspective. Following is a detailed discussion of in vitro data obtained from a variety of neurotransmitter systems. The next section explores applications of autoradiography, and the final two chapters consider experimental models. Methodological considerations are emphasized, including the use of computers for image analysis.

  9. The Vanadium(V) Oxoazides [VO(N3)3], [(bipy)VO(N3)3], and [VO(N3)5](2-).

    PubMed

    Haiges, Ralf; Vasiliu, Monica; Dixon, David A; Christe, Karl O

    2015-07-27

    Vanadium(V) oxoazide [VO(N3)3] was prepared through a fluoride-azide exchange reaction between [VOF3] and Me3SiN3 in acetonitrile solution. When the highly impact- and friction-sensitive compound [VO(N3)3] was reacted with 2,2?-bipyridine, the adduct [(bipy)VO(N3)3] was isolated. The reaction of [VO(N3)3] with [PPh4]N3 resulted in the formation and isolation of the salt [PPh4]2[VO(N3)5]. The adduct [(bipy)VO(N3)3] and the salt [PPh4]23[VO(N3)5] were characterized by vibrational spectroscopy and single-crystal X-ray structure determination, making these compounds the first structurally characterized vanadium(V) azides. PMID:26072899

  10. Eine FPAA-Architektur zur rekonfigurierbaren Instantiierung von zeitkontinuierlichen Analogfiltern

    NASA Astrophysics Data System (ADS)

    Becker, J.; Manoli, Y.

    2005-05-01

    Im Folgenden wird eine neue Methodik von FPAAs (Field Programmable Analog Arrays) gezeigt, die speziell für die Instantiierung von zeitkontinuierlichen (continuous-time, CT) Analogfiltern in Hardware entwickelt wurde. Die Chiptopologie beinhaltet 17 digital konfigurierbare analoge Blöcke (configurable analog blocks, CABs), die durch ein hexagonales Netzwerk miteinander verbunden sind. Jeder CAB ist aus einstellbaren Gm-C Integratoren aufgebaut, welche das analoge Signal sowohl formen und seinen Weg durch die Matrix festlegen, gleichzeitig aber auch die Grundbausteine für zeitkontinuierliche Hochfrequenzfilter darstellen. Intelligente Pufferspeicher für die Ein-/Ausgänge (IO-buffer) garantieren die Rekonfigurierung der Matrix mit minimaler Störung des kontinuierlichen Analogsignals. Die Architektur wird als Hardwareplattform für beliebige Schaltungen, welche aus einer gegebenen Anzahl an Gm-C-Zellen bestehen, eingeführt und verifiziert bevor eine exemplarische Instantiierung eines Butterworth Filters 4. Ordnung in Biquad Anordnung gezeigt wird.

  11. Von eingebetteten Systemen zu Cyber-Physical Systems

    NASA Astrophysics Data System (ADS)

    Wedde, Rorst F.; Lehnhoff, Sebastian; Rehtanz, Christian; Krause, Olav

    Das Hauptanliegen des Papiers ist, ein Paradigma für Probleme mit neuartigen Integrationsanforderungen für Forschung und Entwicklung in verteilten eingebetteten Echtzeitsystemen zu motivieren und vorzustellen, nämlich den Begriff Cyber-Physical Systems. Bei einer in letzter Zeit stark zunehmenden Anzahl von Realzeitanwendungen können ohne die Berücksichtigung solcher Forderungen keine praktisch brauchbaren Lösungen erwartet werden. Einige Anwendungsfelder werden angesprochen. Im Einzelnen werden dann für Elektroautos, die mit erneuerbaren Energien betrieben werden sollen, einerseits die Management-, verteilte Verhandlungs- und Verteilungsprobleme der benötigten Energie in einem bottom-up Ansatz gelöst. Andererseits wird als Teil unserer Projektarbeit die Bereitstellung von Reserveenergie für den allgemeinen Bedarf durch Autobatterien vorgestellt. Es zeigt sich, dass dies effizienter und wesentlich kurzfristiger in unserem verteilten Vorgehen geschehen kann als in traditionellen Verfahren.

  12. Spontaneous hemothorax in patients with von Recklinghausen's disease.

    PubMed

    Miura, Takashi; Kawano, Yozo; Chujo, Masao; Miyawaki, Michiyo; Mori, Hiromu; Kawahara, Katsunobu

    2005-12-01

    Spontaneous massive intrathoracic bleeding is rare except for the rupture of aortic aneurysm or pleural adhesions in association with pneumothorax. We encountered two cases of critical massive hemothorax in patients with von Recklinghausen's disease (type I neurofibromatosis). Case 1; a 59-year-old female suddenly experienced severe back pain followed by syncope and shock. The hemothorax was caused by a bleeding of diffuse type neurofibroma of the parietal pleura and she underwent thoracotomy and surgical ligation of the bleeding vessels. Case 2; a 46-year-old male suddenly suffered back pain and fainted while driving. An intercostal aneurysmal rupture caused a spontaneous hemothorax and he underwent chest tube drainage followed by endovascular coil embolization. We reviewed 23 cases reported in the literature, including our two cases. Spontaneous hemothorax in patients with von Recklinghausen's disease is a life-threatening syndrome and may require emergency surgical or endovascular embolization. PMID:16408472

  13. Marshall-Stickler phenotype associated with von Willebrand disease

    SciTech Connect

    MacDonald, M.R.; Baker, K.S.; Schaefer, G.B.

    1997-01-20

    We report on 6 individuals from three different kindreds with Marshall-Stickler (MS) phenotype, with characteristic orofacial abnormalities, arthropathy, deafness, and eye findings, all of whom were discovered to have a mild bleeding diathesis and coagulation-study findings consistent with mild von Willebrand disease (vWD). MS syndrome has been linked in some cases to the type II procollagen gene (COL2A1) on chromosome 12q, and to the collagen XI gene (COL11A2) on chromosome 6. The von Willebrand factor (vWF) is encoded by a 180-Kb gene located on the short arm of chromosome 12. This is the first reported association of these two disorders. 26 refs., 5 figs., 1 tab.

  14. Instrumentation for Studies of Cochlear Mechanics: From von Békésy forward

    PubMed Central

    Nuttall, Alfred L; Fridberger, Anders

    2012-01-01

    Georg von Békésy designed the instruments needed for his research. He also created physical models of the cochlea allowing him to manipulate the parameters (such as volume elasticity) that could be involved in controlling traveling waves. This review is about the specific devices that he used to study the motion of the basilar membrane thus allowing the analysis that lead to his Nobel Prize Award. The review moves forward in time mentioning the subsequent use of von Békésy’s methods and later technologies important for motion studies of the organ of Corti. Some of the seminal findings and the controversies of cochlear mechanics are mentioned in relation to the technical developments. PMID:22975360

  15. The molecular characterization of von Willebrand disease: Good in parts

    PubMed Central

    James, P.D.; Lillicrap, D.

    2014-01-01

    Summary Since the cloning of the gene that encodes von Willebrand factor (VWF), 27 years ago, significant progress has been made in our understanding of the molecular basis of the most common inherited bleeding disorder, von Willebrand disease (VWD). The molecular pathology of this condition represents a range of genetic mechanisms, some of which are now very well characterized, and others that are still under investigation. In general, our knowledge of the molecular basis of type 2 and 3 VWD is now well advanced, and in some instances this information is being used to enhance clinical management. In contrast, our understanding of the molecular pathogenesis of the most common form of VWD, type 1 disease, is still at an early stage, with preliminary evidence that this phenotype involves a complex interplay between environmental factors and the influence of genetic variability both within and outside of the VWF locus. PMID:23406206

  16. Quantitative Decision Support Requires Quantitative User Guidance

    NASA Astrophysics Data System (ADS)

    Smith, L. A.

    2009-12-01

    Is it conceivable that models run on 2007 computer hardware could provide robust and credible probabilistic information for decision support and user guidance at the ZIP code level for sub-daily meteorological events in 2060? In 2090? Retrospectively, how informative would output from today’s models have proven in 2003? or the 1930’s? Consultancies in the United Kingdom, including the Met Office, are offering services to “future-proof” their customers from climate change. How is a US or European based user or policy maker to determine the extent to which exciting new Bayesian methods are relevant here? or when a commercial supplier is vastly overselling the insights of today’s climate science? How are policy makers and academic economists to make the closely related decisions facing them? How can we communicate deep uncertainty in the future at small length-scales without undermining the firm foundation established by climate science regarding global trends? Three distinct aspects of the communication of the uses of climate model output targeting users and policy makers, as well as other specialist adaptation scientists, are discussed. First, a brief scientific evaluation of the length and time scales at which climate model output is likely to become uninformative is provided, including a note on the applicability the latest Bayesian methodology to current state-of-the-art general circulation models output. Second, a critical evaluation of the language often employed in communication of climate model output, a language which accurately states that models are “better”, have “improved” and now “include” and “simulate” relevant meteorological processed, without clearly identifying where the current information is thought to be uninformative and misleads, both for the current climate and as a function of the state of the (each) climate simulation. And thirdly, a general approach for evaluating the relevance of quantitative climate model output for a given problem is presented. Based on climate science, meteorology, and the details of the question in hand, this approach identifies necessary (never sufficient) conditions required for the rational use of climate model output in quantitative decision support tools. Inasmuch as climate forecasting is a problem of extrapolation, there will always be harsh limits on our ability to establish where a model is fit for purpose, this does not, however, limit us from identifying model noise as such, and thereby avoiding some cases of the misapplication and over interpretation of model output. It is suggested that failure to clearly communicate the limits of today’s climate model in providing quantitative decision relevant climate information to today’s users of climate information, would risk the credibility of tomorrow’s climate science and science based policy more generally.

  17. [Carl Friedrich von Weizsäcker's philosophy of the mind].

    PubMed

    Lyre, Holger

    2014-01-01

    The paper deals with Carl Friedrich von Weizsäcker's position within the philosophy of mind. It turns out that Weizsäcker's ontology is based on an unorthodox conception both in the philosophy of physics and in the philosophy of mind. His quantum information theoretic reductionism is based on a subtle combination of atomism and holism, his philosophy of mind connected to this is a neutral monism, which proposes a bold intertwining of mind, matter, and space. PMID:24974603

  18. Dr. von Braun In Front of a Display of Missiles

    NASA Technical Reports Server (NTRS)

    1960-01-01

    In this photo, Director of the US Army Ballistic Missile Agency (ABMA) Development Operations Division, Dr. Wernher von Braun, is standing before a display of Army missiles celebrating ABMA's Fourth Open House. The missiles in the background include (left to right) a satellite on a Juno II shroud with a Nike Ajax pointing left in front of a Jupiter missile. The Lacrosse is in front of the Juno II. The Nike Hercules points skyward in front of the Juno II and the Redstone.

  19. Kernschmelze Der nachhaltige Einfluss von Nuklearwaffen auf Politik und Wirtschaft

    NASA Astrophysics Data System (ADS)

    Greiner, Bernd

    "Was sollen wir von einer Kultur halten, der die Ethik stets als wesentliches Element des menschlichen Lebens galt, die aber - außer in fachlicher oder spieltheoretischer Terminologie - nicht in der Lage war, über die Möglichkeit zu sprechen, nahezu alle Menschen zu töten?" Der Fragesteller gehört zu den berühmtesten Physikern des 20. Jahrhunderts und zu den nach wie vor Umstrittensten. über ihn wurde in den 1960er Jahren ein international viel beachtetes Theaterstück geschrieben, vor wenigen Jahren gar eine Oper.

  20. Dr. Wernher Von Braun at the launch of Apollo 11.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mission officials relax, all smiles, a few moments after the successful launch of the Apollo 11 spacecraft by Saturn V vehicle AS-506. Relieved of the tension of waiting through the countdown are (left to right) Charles W. Matthews, NASA deputy associate administrator for manned space flight; Dr. Wernher Von Braun, Director of the Marshall Space Flight Center; Dr. George E. Meuller, NASA associate administrator for manned spaceflight, and Lt. General Samuel C. Phillips, director of the Apollo program.

  1. Malignant duodenal somatostatinoma presenting in association with von Recklinghausen disease.

    PubMed

    Patel, Vijaykumar G; Henderson, Vernon J; Fairweather, David A; Fortson, James K; Weaver, William L; Martin, David M; Lyons, Ralph; Hamami, Amir

    2003-12-01

    Somatostatinomas are extremely rare periampullary malignant neuroendocrine tumors that may be associated with von Recklinghausen disease or type-I neurofibromatosis. Duodenal somatostatinomas are distinguished from pancreatic somatostatinomas by their frequent association with type-I neurofibromatosis and typically absence of somatostatinoma syndrome. We report a very rare and atypical case of malignant duodenal somatostatinoma presenting with somatostatinoma syndrome in association with type-I neurofibromatosis. PMID:14700294

  2. Ehlers-Danlos syndrome combined with von Recklinghausen neurofibromatosis.

    PubMed

    Hashiguchi, T; Maruyama, I; Sonoda, K; Nakashima, H; Nakamura, N; Sonoda, Y; Osame, M

    1992-05-01

    We recently had the opportunity to study a 25-year-old male with both Ehlers-Danlos syndrome (EDS) and von Recklinghausen neurofibromatosis (VRNF). We describe the clinical manifestations of the case and discuss the probable pathomechanism of the combination of the two syndromes, with a review of the literature. As recent literature suggests that both syndromes are linked to chromosome 17, we conclude that their combination is not coincidental, but genetically linked. PMID:1504434

  3. Nutzergerechte Entwicklung der Mensch-Maschine-Interaktion von Fahrerassistenzsystemen

    NASA Astrophysics Data System (ADS)

    König, Winfried

    Durch langjährige Forschungen bei Kfz-Herstellern, Zulieferfirmen und an Hochschulen sind umfangreiche, aber dennoch lückenhafte Erkenntnisse über das Zusammenspiel zwischen FAS und Nutzer gewonnen worden. In deutschen und internationalen Projekten wie z. B. PROMETHEUS, DRIVE, MOTIV, INVENT, RESPONSE und AKTIV haben sich Kfz-Hersteller, Zulieferfirmen, Hochschulen und weitere staatliche und private Forschungseinrichtungen zusammengefunden, um die vorwettbewerbliche Forschung für derartige Systeme voranzutreiben. Im folgenden Kapitel sollen einige der gewonnenen Kenntnisse dargelegt werden, um die Entwicklung des HMI von FAS zu erleichtern.

  4. Baron von Zach's business relations with the Munich entrepreneur Joseph von Utzschneider (German Title: Geschäftsbeziehungen des Barons von Zach zu dem Münchner Unternehmer Joseph von Utzschneider)

    NASA Astrophysics Data System (ADS)

    Schneider, Ivo

    The relationship between the astronomer von Zach on the one side and the entrepreneur Joseph von Utzschneider and his partner Georg von Reichenbach on the other dates presumably from the year 1807 when Zach spent two months in Munich. Already in the same year Zach had ordered an instrument for himself and began to solicit business for the institute of Reichenbach, Utzschneider, and Liebherr, which was founded in 1804. One of the clients canvassed by Zach was the director of the observatory in Naples Zuccari. Zuccari had ordered the whole equipment for the new observatory from this institute in 1813. The instruments for Naples, which were completed in 1814, were sent accompanied by Reichenbach by land and sea to their destination where Reichenbach supervised their setup. At that time Reichenbach had separated from Utzschneider who kept the optical institute in Benediktbeuern with his new partner Joseph von Fraunhofer whereas Reichenbach became owner of the mathematical-mechanical institute in Munich. For personal and economical reasons Utzschneider began soon after to produce not only optical glass but also optical devices similar to those offered by Reichenbach. As soon as two institutes in Munich competed against each other on the market for sophisticated geodetical and astronomical instruments Zach sided with Utzschneider. Zach's main professional argument for this decision was that both competitors got the optical glass for their instruments from Utzschneider's optical institute in Benediktbeuern. This meant that Utzschneider had first choice and so the optical part of his instruments could be considered as better than that of Reichenbach`s instruments. Zach's role as an agent in Italy and France for the sale of products coming from Utzschneider's manufactories is highlighted by three of Zach's letters to Utzschneider from 1817 and 1818, two of which are reproduced here for the first time.

  5. Interpolatability distinguishes LOCC from separable von Neumann measurements

    SciTech Connect

    Childs, Andrew M.; Leung, Debbie; Man?inska, Laura; Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario N2L 3G1 ; Ozols, Maris; Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario N2L 3G1; IBM TJ Watson Research Center, Yorktown Heights, New York 10598

    2013-11-15

    Local operations with classical communication (LOCC) and separable operations are two classes of quantum operations that play key roles in the study of quantum entanglement. Separable operations are strictly more powerful than LOCC, but no simple explanation of this phenomenon is known. We show that, in the case of von Neumann measurements, the ability to interpolate measurements is an operational principle that sets apart LOCC and separable operations.

  6. Observations of minor planets at the Dresden Lohrmann Observatory.

    NASA Astrophysics Data System (ADS)

    Asenjo, E.

    Von 1949 bis 1974 wurden mehr als 21000 photographische Beobachtungen von zehn durch das Institut für Theoretische Astronomie (ITA) der AdW der UdSSR in Leningrad ausgewählten kleinen Planeten in verschiedenen Sternwarten der Welt durchgeführt. Eine Tabelle zeigt eine Zusammenstellung der Ergebnisse zur Bestimmung der Verbesserung von Äquinoktium und Äquator des FK4.

  7. Möglichkeiten und Grenzen der Kompression von Femtosekunden-Lichtimpulsen

    NASA Astrophysics Data System (ADS)

    Wilhelmi, Bernd

    Aus der Wellengleichung werden Beziehungen zur Beschreibung des simultanen Einflusses von Dispersion und Nichtlinearität verschiedener Ordnung auf ultrakurze Lichtimpulse in Materialien, deren Eigenfrequenzen weit von der Mittenfrequenz des Lichtes entfernt liegen, hergeleitet. Unter bestimmten Voraussetzungen über Eingangsimpuls und Material nehmen diese Beziehungen die Struktur der nichtlinearen Schrödinger-Gleichung an, deren Anwendungsbereich dadurch abgesteckt werden kann. Es werden Bedingungen für die Erzeugung von komprimierten, chirp-freien Impulsen angegeben und Grenzen für die erreichbare Impulsdauer diskutiert.Translated AbstractPossibilities and Limitations of Compression of Femtosecond Light PulsesRelations have been derived that describe the simultaneous action of dispersion and nonlinearities of various orders on ultrashort light pulses in samples, the eigen frequencies of which are far from the center frequency of the incoming light. Under certain assumptions, with respect to input pulse and material, these relations attain the structure of the nonlinear Schrödinger-equation, the application range of which has been estimated in this way. Conditions for the generation of compressed, chirp-free pulses are given and limits for the minimum obtainable pulse duration are discussed.

  8. Sequence and structure relationships within von Willebrand factor.

    PubMed

    Zhou, Yan-Feng; Eng, Edward T; Zhu, Jieqing; Lu, Chafen; Walz, Thomas; Springer, Timothy A

    2012-07-12

    In the present study, we re-annotated von Willebrand factor (VWF), assigned its entire sequence to specific modules, and related these modules to structure using electron microscopy (EM). The D domains are assemblies of smaller modules visible as lobes in EM. Modules in the D-domain assemblies include von Willebrand D, 8-cysteine, trypsin inhibitor-like, E or fibronectin type 1-like domains, and a unique D4N module in D4. The D1-D2 prodomain shows 2 large connected assemblies, each containing smaller lobes. The previous B and C regions of VWF are re-annotated as 6 tandem von Willebrand C (VWC) and VWC-like domains. These 6 VWC domains correspond to 6 elongated domains that associate in pairs at acidic pH in the stem region of VWF dimeric bouquets. This correspondence is demonstrated by binding of integrin α(IIb)β(3) to the fourth module seen in EM, VWC4, which bears the VWF Arg-Gly-Asp motif. The C-terminal cystine knot domain dimerizes end-to-end in a manner predicted by homology to TGF-β and orients approximately perpendicular to the VWC domains in dimeric bouquets. Homologies of domains in VWF to domains in other proteins allow many disulfide bonds to be tentatively assigned, which may have functional implications. PMID:22490677

  9. Einflüsse von Fahrerassistenzsystemen auf die Systemarchitektur im Kraftfahrzeug

    NASA Astrophysics Data System (ADS)

    Reichart, Günter; Bielefeld, Jürgen

    Die Komplexität der Systeme bei modernen, hoch ausgestatteten Fahrzeugen hat ein hohes Niveau erreicht. Auch in Zukunft werden Innovationen im Kraftfahrzeug vermehrt nur über hochvernetzte und komplexe Systeme zu realisieren sein. Dies gilt in besonderem Maße für das Gebiet der Fahrerassistenz. Aufgrund der Nutzung von sensorisch erfasster Information über die Fahrumgebung, fahrzeuglokaler Daten und der Nutzung der bereits im Fahrzeug verbauten Aktorik sind Fahrerassistenzsysteme geradezu ein Synonym für verteilte hochvernetzte Funktionen. Umfang und Qualität der sensorisch erfassbaren Information und ihre Interpretation bestimmen den Funktionsumfang und die Komplexität der jeweiligen Assistenzfunktion wesentlich. Die technische Sensorik, z. B. Radar oder Kamerasysteme, nutzt gleiche oder ähnliche Information wie der Fahrer. Es wird allerdings auch auf längere Sicht keine Sensorik geben, die die Gesamtheit der Wahrnehmungsleistungen des Menschen und seine Fähigkeit der Interpretation dieser Daten in unterschiedlichen Kontexten erreicht. In einzelnen Aspekten sind technische Sensoren aber durchaus der menschlichen Wahrnehmung überlegen, wie beispielsweise bezüglich Daueraufmerksamkeit, Geschwindigkeitsbestimmung bewegter Objekte oder aufgrund von Empfindlichkeit in anderen Wellenlängenbereichen als der des menschlichen Auges. Insbesondere die Verknüpfung der Sensorinformationen, die so genannte Sensorfusion, bietet ein hohes Potenzial, den Fahrer zu entlasten und die Fahrsicherheit zu erhöhen bzw. kritischen Fahrsituationen vorzubeugen. Durch die Sensorfusion wird die Qualität der Interpretation von mit technischer Sensorik erfassten Daten deutlich erhöht. Hierzu sind Entscheidungen über die Fusionsebene wie Rohdaten, aufbereitete oder interpretierte Daten zu treffen sowie geeignete Fusionsarchitekturen im Fahrzeug vorzusehen (siehe Kapitel 17).

  10. The British Interplanetary Society - Val Cleaver and Wernher von Braun

    NASA Astrophysics Data System (ADS)

    Willhite, I. P.

    This article is concerned with the early relationship between Wernher von Braun and the British Interplanetary Society (BIS). The BIS/Wernher von Braun/Val Cleaver correspondence files located here at the US Space & Rocket Center in Huntsville, Alabama are unparalleled. As one reads the stimulating comments between Cleaver and von Braun, the need to share their thoughts prevails. Following is an excerpt from one letter that whets ones appetite for more. 10 June 1951 Cleaver writes, “I'm so glad you enjoyed my last letter, and look forward to your promised further contribution to our discussion of the ethics of science in general and astronautics in particu- lar. As regards the one particular point on which you found yourself unable to hold your fire, I should say there are really two distinct issues at stake:. . .” This article attempts to represent the best of the letters as they goad each other on scientific principles, means to prevent wars, and other philosophic ideas.

  11. Quantitative photoacoustic tomography

    PubMed Central

    Yuan, Zhen; Jiang, Huabei

    2009-01-01

    In this paper, several algorithms that allow for quantitative photoacoustic reconstruction of tissue optical, acoustic and physiological properties are described in a finite-element method based framework. These quantitative reconstruction algorithms are compared, and the merits and limitations associated with these methods are discussed. In addition, a multispectral approach is presented for concurrent reconstructions of multiple parameters including deoxyhaemoglobin, oxyhaemoglobin and water concentrations as well as acoustic speed. Simulation and in vivo experiments are used to demonstrate the effectiveness of the reconstruction algorithms presented. PMID:19581254

  12. Quantitative Hydrocarbon Surface Analysis

    NASA Technical Reports Server (NTRS)

    Douglas, Vonnie M.

    2000-01-01

    The elimination of ozone depleting substances, such as carbon tetrachloride, has resulted in the use of new analytical techniques for cleanliness verification and contamination sampling. The last remaining application at Rocketdyne which required a replacement technique was the quantitative analysis of hydrocarbons by infrared spectrometry. This application, which previously utilized carbon tetrachloride, was successfully modified using the SOC-400, a compact portable FTIR manufactured by Surface Optics Corporation. This instrument can quantitatively measure and identify hydrocarbons from solvent flush of hardware as well as directly analyze the surface of metallic components without the use of ozone depleting chemicals. Several sampling accessories are utilized to perform analysis for various applications.

  13. Defective dimerization of von Willebrand factor subunits due to a Cys-> Arg mutation in type IID von Willebrand disease.

    PubMed Central

    Schneppenheim, R; Brassard, J; Krey, S; Budde, U; Kunicki, T J; Holmberg, L; Ware, J; Ruggeri, Z M

    1996-01-01

    The same heterozygous T -> C transition at nt 8567 of the von Willebrand factor (vWF) transcript was found in two unrelated patients with type III) von Willebrand disease, with no other apparent abnormality. In one family, both alleles were normal in the parents and one sister; thus, the mutation originated de novo in the proposita. The second patient also had asymptomatic parents who, however, were not available for study. The structural consequences of the identified mutation, resulting in the CyS2010 -> Arg substitution, were evaluated by expression of the vWF carboxyl-terminal domain containing residues 1366-2050. Insect cells infected with recombinant baculovirus expressing normal vWF sequence secreted a disulfide linked dimeric molecule with an apparent molecular mass of 150 kDa before reduction, yielding a single band of 80 kDa after disulfide bond reduction. In contrast, cells expressing the mutant fragment secreted a monomeric molecule of apparent molecular mass of 80 kDa, which remained unchanged after reduction. We conclude that CyS2010 is essential for normal dimerization of vWF subunits through disulfide bonding of carboxyl-terminal domains and that a heterozygous mutation in the corresponding codon is responsible for defective multimer formation in type III) von Willebrand disease. Images Fig. 1 Fig. 2 Fig. 4 PMID:8622978

  14. Acquired type 2a von Willebrand's disease: response to immunoglobulin infusion.

    PubMed

    Sampson, B; Anderson, D R; Dugal, M; Ing, V W; Zayed, E

    1997-01-01

    A 75-year-old male presented with new symptoms of a bleeding diathesis associated with a decline in the functional activity of von Willebrand factor (type 2a von Willebrand's disease). Replacement therapy was ineffective and he was subsequently treated with intravenous immunoglobulin (IvIg). IvIg not only caused symptomatic improvement but was shown to transiently restore the depleted von Willebrand factor intermediate and high molecular weight multimers. Subsequent periodic IvIg infusions have been used successfully to treat bleeding complications in this patient over the past 3 years. A secondary cause for the acquired von Willebrand's disease has not been identified. PMID:9731109

  15. Quantitative Simulation Games

    NASA Astrophysics Data System (ADS)

    ?erný, Pavol; Henzinger, Thomas A.; Radhakrishna, Arjun

    While a boolean notion of correctness is given by a preorder on systems and properties, a quantitative notion of correctness is defined by a distance function on systems and properties, where the distance between a system and a property provides a measure of "fit" or "desirability." In this article, we explore several ways how the simulation preorder can be generalized to a distance function. This is done by equipping the classical simulation game between a system and a property with quantitative objectives. In particular, for systems that satisfy a property, a quantitative simulation game can measure the "robustness" of the satisfaction, that is, how much the system can deviate from its nominal behavior while still satisfying the property. For systems that violate a property, a quantitative simulation game can measure the "seriousness" of the violation, that is, how much the property has to be modified so that it is satisfied by the system. These distances can be computed in polynomial time, since the computation reduces to the value problem in limit average games with constant weights. Finally, we demonstrate how the robustness distance can be used to measure how many transmission errors are tolerated by error correcting codes.

  16. Quantitative Decision Making.

    ERIC Educational Resources Information Center

    Baldwin, Grover H.

    The use of quantitative decision making tools provides the decision maker with a range of alternatives among which to decide, permits acceptance and use of the optimal solution, and decreases risk. Training line administrators in the use of these tools can help school business officials obtain reliable information upon which to base district…

  17. Critical Quantitative Inquiry in Context

    ERIC Educational Resources Information Center

    Stage, Frances K.; Wells, Ryan S.

    2014-01-01

    This chapter briefly traces the development of the concept of critical quantitative inquiry, provides an expanded conceptualization of the tasks of critical quantitative research, offers theoretical explanation and justification for critical research using quantitative methods, and previews the work of quantitative criticalists presented in this…

  18. Variabilität des Reviergesangs des Buchfinken (Fringilla coelebs) zur Raum-Zeit-Beschreibung von Metapopulationen

    NASA Astrophysics Data System (ADS)

    Nolte, Björn

    2003-10-01

    Der Buchfinkengesang wurde in Potsdam in zwei Hauptpopulationen über drei Jahre aufgenommen. Jedes Individuum wurde eindeutig am individuellen Strophentypenrepertoire identifiziert. Ein weiterer Punkt der die individuelle Wiedererkennung bestätigt ist die hohe Standorttreue der adulten Männchen. Die beschriebene Methode eignet sich für die Untersuchung von gesamten Populationen, um den Wandel des Gesangs von Populationen in Raum und Zeit zu beschreiben. Die Haupterkenntnisse der Arbeit sind: - Die Gesamtanzahl der Grundstrophentypen innerhalb einer Population bleibt über Jahre konstant. - Die relative Häufigkeit jedes einzelnen Strophentyps variiert von Jahr zu Jahr und von Population zu Population. - Gesangslernen erfolgt exakt mit einem Korrektheitsgrad von mindestens 96%. - Das Song-Sharing ist innerhalb der Population hoch. Die diskutierten Mechanismen für das Song-Sharing sind: Die Lebenserwartung, das Zugverhalten, das Lernverhalten, die Etabliertheit von Strophentypen, Weibchenpräferenzen und die Reaktionen der territorialen Männchen. - Weiterhin wurde ein Modell zur kulturellen Evolution des Buchfinkengesangs programmiert, um die Rolle der Einflussfaktoren, wie Fehlerquote, Abwanderungsrate und Laufzeit zu ermitteln. Der Wandel des Dialektes erfolgt graduell in Raum und Zeit. Daher sind keine scharfen Dialektgrenzen anzutreffen. Trotz dieser Tatsache markieren die etablierten Strophentypen die Population. 50 % der Juvenilen siedeln am Geburtsort, auf diese Weise bleibt der Dialekt erhalten und Inzest wird vermieden. -Analysiert man das Repertoire benachbarten Männchen bei isolierten Alleen, so entspricht die Gesangsangleichung in etwa dem Zufall. -Intraindividuelle Vergleiche der quantitativen Parameter des jeweiligen Strophentyps wurden saisonal und annuell durchgeführt. Saisonal konnten für einen Strophentyp ein Trend ermittelt werden. Bei jährlichen Vergleichen konnten intraindividuell ausschließlich nicht signifikante Ergebnisse ermittelt werden, wohingegen die interindividuelle Variation in zwei Fällen signifikant war. In einem Fall bestand ein Trend und in einem weiteren Fall war die Variationsunterschiede nicht signifikant. - Der Verlauf der Brutsaison lässt sich an der jährlichen Gesangsaktivität nachvollziehen. Chaffinch song was recorded in Potsdam in two major populations of chaffinches over a period of three years. Each male was identified unambiguously because of their individual song type repertoires. These are usually easy to distinguish from sonagrams as the variation is discontinuous. A further point for individual recognition is the fixed territorial behaviour of adult males. The described method is employed to examine whole populations and to observe changes with space and time in the song of a population. The major findings of the study are: - The total amount of basic song types in each population is constant over years. - The quantity of each basic song type is different and varies from year to year and from population to population. - Song copying is extremely accurate on at least 96% of occasions. - Song-type sharing is high within populations. Discussed mechanisms for song neighbourhoods are: expectation of life, semi-migratory behaviour, learning skills, establishment of song types, female choice and male vs male interaction. Furthermore a model of cultural evolution of chaffinch song was programmed to determine the role of factors like error rate, rate of emigration and running time. The changes are gradual in space and time. Hence the dialect borders are smooth. Despite this fact established song types mark the population. As every second juvenile bird settles in the population of his birth inbreeding is avoided and the dialect structure is retained. - Analysing the repertoires of neighbouring males (“next door neighbours”) in isolated avenues to examine mutual influences suggests that these have the same amount of song types in common than would be expected by chance. - Within intraindividual comparisons the quantitative parameters of the same song types remain seasonal and annual constant, whereas interindividual variations within the same song tip are statistically significant. - The breeding biology of the chaffinch can be observed by seasonal singing activity during the breeding cycle.

  19. AB110. The first prenatal diagnosis of von Hippel-Lindau syndrome in Chinese mainland

    PubMed Central

    Peng, Shuanghe; Li, Teng; Wang, Jiangyi; Gong, Kan

    2015-01-01

    Objective Von Hippel-Lindau (VHL) syndrome is an autosomal dominantly inherited familial cancer syndrome caused by germline mutations in VHL tumor suppressor gene. It is characterized by multisystem neoplastic disorder which cannot be cured radically now, and the gold diagnosis standard is the genetic test of VHL gene. The purpose of this study is to explore the feasibility of applying VHL gene detesting technology combined with short tandem repeats analysis to finish the prenatal diagnosis of VHL syndrome. Methods This was the first pregnancy of a 30-year-old woman diagnosed with VHL syndrome 2 years ago. At 20 weeks of gestation, the woman underwent amniocentesis. We apply VHL gene detesting technology (PCR-direct sequencing and universal primer quantitative fluorescent multiplex PCR) combined with short tandem repeats analysis to test the fetal DNA in amniotic fluid. Results Under the premise of excluding maternal cells pollution by short tandem repeats analysis, fetal VHL gene analysis detected c.499C>T p.Arg167Trp mutation as the same as the mother. Conclusions We finished the first prenatal diagnosis of VHL syndrome in Chinese mainland. Combining VHL gene detesting technology with short tandem repeats analysis can be used to finish the prenatal diagnosis of VHL syndrome.

  20. Berkeley Quantitative Genome Browser

    SciTech Connect

    2008-02-29

    The Berkeley Quantitative Genome Browser provides graphical browsing functionality for genomic data organized, at a minimum, by sequence and position. While supporting the annotation browsing features typical of many other genomic browsers, additional emphasis is placed on viewing and utilizing quantitative data. Data may be read from GFF, SGR, FASTA or any column delimited format. Once the data has been read into the browser's buffer, it may be searched. filtered or subjected to mathematical transformation. The browser also supplies some graphical design manipulation functionality geared towards preparing figures for presentations or publication. A plug-in mechanism enables development outside the core functionality that adds more advanced or esoteric analysis capabilities. BBrowse's development and distribution is open-source and has been built to run on Linux, OSX and MS Windows operating systems.

  1. Berkeley Quantitative Genome Browser

    Energy Science and Technology Software Center (ESTSC)

    2008-02-29

    The Berkeley Quantitative Genome Browser provides graphical browsing functionality for genomic data organized, at a minimum, by sequence and position. While supporting the annotation browsing features typical of many other genomic browsers, additional emphasis is placed on viewing and utilizing quantitative data. Data may be read from GFF, SGR, FASTA or any column delimited format. Once the data has been read into the browser's buffer, it may be searched. filtered or subjected to mathematical transformation.more » The browser also supplies some graphical design manipulation functionality geared towards preparing figures for presentations or publication. A plug-in mechanism enables development outside the core functionality that adds more advanced or esoteric analysis capabilities. BBrowse's development and distribution is open-source and has been built to run on Linux, OSX and MS Windows operating systems.« less

  2. Energy & Climate: Getting Quantitative

    NASA Astrophysics Data System (ADS)

    Wolfson, Richard

    2011-11-01

    A noted environmentalist claims that buying an SUV instead of a regular car is energetically equivalent to leaving your refrigerator door open for seven years. A fossil-fuel apologist argues that solar energy is a pie-in-the-sky dream promulgated by na"ive environmentalists, because there's nowhere near enough solar energy to meet humankind's energy demand. A group advocating shutdown of the Vermont Yankee nuclear plant claims that 70% of its electrical energy is lost in transmission lines. Around the world, thousands agitate for climate action, under the numerical banner ``350.'' Neither the environmentalist, the fossil-fuel apologist, the antinuclear activists, nor most of those marching under the ``350'' banner can back up their assertions with quantitative arguments. Yet questions about energy and its environmental impacts almost always require quantitative answers. Physics can help! This poster gives some cogent examples, based on the newly published 2^nd edition of the author's textbook Energy, Environment, and Climate.

  3. Relevance of quantitative assessment of bleeding in haemorrhagic disorders.

    PubMed

    Rodeghiero, F; Kadir, R A; Tosetto, A; James, P D

    2008-07-01

    In the last few years, there has been a growing interest in the diagnosis of mild bleeding disorders (MBD) to find reliable tools for the assessment of their inherent bleeding risk and minimum criteria for the definition of a clinically useful diagnosis. Unlike in more severe haemorrhagic disorders, in MBD, the bleeding history may overlap with that reported by normal people. This problem has required the development of strategies that could allow the assessment of bleeding symptoms from both a qualitative (presence or absence) and quantitative (bleeding severity) aspect. An example of high quality clinical research in bleeding disorders was given by the systematic approach used for the evaluation of menorrhagia. For this symptom, the most common in women with bleeding disorders, the use of pictorial charts provided many new insights. Dr Kadir will review its use in a clinical context. The assessment of the whole bleeding history requires first, the development of reproducible tools to collect symptoms and secondly, formulation of easily applicable criteria to convert the collected data into clinical information. Dr Tosetto will propose a bleeding questionnaire in which clinical criteria were developed and validated, and show how a summative, quantitative index of bleeding severity (the Bleeding Score) could be used in von Willebrand disease. Finally, Dr James will review the development of quantitative analysis in children, a particularly important and difficult application, but one that needs to be tackled urgently. PMID:18510525

  4. Primary enzyme quantitation

    DOEpatents

    Saunders, G.C.

    1982-03-04

    The disclosure relates to the quantitation of a primary enzyme concentration by utilizing a substrate for the primary enzyme labeled with a second enzyme which is an indicator enzyme. Enzyme catalysis of the substrate occurs and results in release of the indicator enzyme in an amount directly proportional to the amount of primary enzyme present. By quantifying the free indicator enzyme one determines the amount of primary enzyme present.

  5. [On the centennial of Ernst von Bergmann's death].

    PubMed

    Czymek, R; Düsel, W

    2007-03-01

    "dear aunt lina. i do not know any big letters yet, but i want to thank you in small letters for the beautiful pens. say hello to grandpa and to everybody. yours truly, ernst." These are the first surviving written words of Ernst von Bergmann. Between them and his last words about his suspected colon cancer on 25 March 1907 ("I diagnosed this 5 years ago, and now it has come to pass.") lie many years in a vigorous life characterised by untiring activity and creativity, self-discipline, and care for patients and his family. They were years of enormous success in surgery and private happiness but also of professional setbacks and tragic family loss. Ernst von Bergmann became a leading German surgeon not only because of his surgical and scientific achievements, particularly in the fields of asepsis and war surgery, but also due to his exemplary character, reliability, engaging personality, and commitment to medical training in various medical societies. Of these, the German Society of Surgery is most indebted to him. After assuming a chair in surgery in 1882, he continued to play a leading role in this society, not least as its five-time president from 1888 to 1890 and in 1896 and 1900. A worthy successor to Bernhard von Langenbeck, he was a full professor at the Berlin University Hospital for 25 years. He also taught at the Medical and Surgical Academy for the Military after being appointed there by Emperor Wilhelm I on 16 November 1882. This position was important to him and corresponded to his patriotic views. PMID:17287931

  6. Spin torque oscillator neuroanalog of von Neumann's microwave computer.

    PubMed

    Hoppensteadt, Frank

    2015-10-01

    Frequency and phase of neural activity play important roles in the behaving brain. The emerging understanding of these roles has been informed by the design of analog devices that have been important to neuroscience, among them the neuroanalog computer developed by O. Schmitt and A. Hodgkin in the 1930s. Later J. von Neumann, in a search for high performance computing using microwaves, invented a logic machine based on crystal diodes that can perform logic functions including binary arithmetic. Described here is an embodiment of his machine using nano-magnetics. Electrical currents through point contacts on a ferromagnetic thin film can create oscillations in the magnetization of the film. Under natural conditions these properties of a ferromagnetic thin film may be described by a nonlinear Schrödinger equation for the film's magnetization. Radiating solutions of this system are referred to as spin waves, and communication within the film may be by spin waves or by directed graphs of electrical connections. It is shown here how to formulate a STO logic machine, and by computer simulation how this machine can perform several computations simultaneously using multiplexing of inputs, that this system can evaluate iterated logic functions, and that spin waves may communicate frequency, phase and binary information. Neural tissue and the Schmitt-Hodgkin, von Neumann and STO devices share a common bifurcation structure, although these systems operate on vastly different space and time scales; namely, all may exhibit Andronov-Hopf bifurcations. This suggests that neural circuits may be capable of the computational functionality as described by von Neumann. PMID:26135205

  7. Structure and coarsening of foams: Beyond von Neumann's law

    NASA Astrophysics Data System (ADS)

    Roth, Adam E.

    We report on the statistics of bubble size, topology, and shape and on their role in the coarsening dynamics for foams consisting of bubbles compressed between two parallel plates. We find that in the scaling regime, all bubble distributions are independent not only of time, but also of liquid content. For coarsening, the average rate decreases with liquid content due to the blocking of gas diffusion by Plateau borders inflated with liquid. By observing the growth rate of individual bubbles, we find that von Neumann's law becomes progressively violated with increasing wetness and decreasing bubble size. We successfully model this behavior by explicitly incorporating the border-blocking effect into the von Neumann argument. We report on bubble growth rates and on the statistics of bubble topology for the coarsening of a dry foam contained in the gap between two hemispheres. By contrast with coarsening in flat space, we observe that six-sided bubbles grow with time at a rate that depends on their size. We measure the statistics of bubble topology, and find distributions that differ from the scaling state of a flat two dimensional foam. We report on the statistics of bubble distribution and coarsening of the two dimensional surface of a three dimensional foam. The surface of a three dimensional foam obeys Plateau's laws, but does not obey von Neumann's law on the individual bubble level, although it holds on average. We measure bubble distributions, which to not change with time, but have different values from an ordinary two dimensional foam. We report on a method for optical tomography of three dimensional foams. Using a bottle filled with dry foam that is mounted on a rotation stage, we take pictures of the foam at many different angles. Using these images, it is possible to reconstruct horizontal slices of the foam. By controlling the parameters of this system, it is possible to get good slices, for possible use in reconstruction of the foam structure.

  8. Reevaluation of McCulloch-Pitts-von Neumann's clock.

    PubMed

    Ohta, Hiroyuki

    2015-01-01

    In neuroscience research, a firing pattern expression, called a firing snapshot, defined by firing counts of multiple neurons in discrete time-bin is frequently used. However, the firing pattern expression over multiple neurons requires synchronization commonly known as a "central clock" in computation circuits to externally control or observe multi-neuron firing. Since it is not appropriate to hypothesize the central clock in the brain, we have to reconsider the synchronization assumption. We found the historical origins of central clock synchronization in the works of McCulloch, Pitts and von Neumann and propose an alternative perspective to study neural processing without the central clock. In the "First draft of a report on the EDVAC" known as the first proposal of store-program type computer, von Neumann incorporated McCulloch and Pitts' arbitrary assumption of constant synaptic delay into the logical circuit modeling. He introduced a constant pulse delay stabilized by a central clock to synchronize multiple pulse lines. This constant delay carried over to automaton theory by von Neumann and then theoretical neuroscience as an integral part of distributed representation and firing pattern analysis. Instead, we propose a rethinking of neuronal processing by focusing on a variable synaptic delay. We review neuron-type dependent differences and point out that the maximum inter-stimulus interval which can affect the last stimulus response is longer than the minimum inter-spike interval, indicating the possibility of asynchronous input summation without a firing rate level clock. This fundamental baseline contributes to the investigation of time consuming processes: e.g., the compression of appositional synaptic inputs with duration into a single firing. PMID:25458264

  9. Computational vaccinology: quantitative approaches.

    PubMed

    Flower, Darren R; McSparron, Helen; Blythe, Martin J; Zygouri, Christianna; Taylor, Debra; Guan, Pingping; Wan, Shouzhan; Coveney, Peter V; Walshe, Valerie; Borrow, Persephone; Doytchinova, Irini A

    2003-01-01

    The immune system is hierarchical and has many levels, exhibiting much emergent behaviour. However, at its heart are molecular recognition events that are indistinguishable from other types of biomacromolecular interaction. These can be addressed well by quantitative experimental and theoretical biophysical techniques, and particularly by methods from drug design. We review here our approach to computational immunovaccinology. In particular, we describe the JenPep database and two new techniques for T cell epitope prediction. One is based on quantitative structure-activity relationships (a 3D-QSAR method based on CoMSIA and another 2D method based on the Free-Wilson approach) and the other on atomistic molecular dynamic simulations using high performance computing. JenPep (http://www.jenner.ar.uk/ JenPep) is a relational database system supporting quantitative data on peptide binding to major histocompatibility complexes, TAP transporters, TCR-pMHC complexes, and an annotated list of B cell and T cell epitopes. Our 2D-QSAR method factors the contribution to peptide binding from individual amino acids as well as 1-2 and 1-3 residue interactions. In the 3D-QSAR approach, the influence of five physicochemical properties (volume, electrostatic potential, hydrophobicity, hydrogen-bond donor and acceptor abilities) on peptide affinity were considered. Both methods are exemplified through their application to the well-studied problem of peptide binding to the human class I MHC molecule HLA-A*0201. PMID:14712934

  10. [Prolonged action of vecuronium in neurofibromatosis (von Recklinghausen's disease)].

    PubMed

    Mitterschiffthaler, G; Maurhard, U; Huter, O; Brezinka, C

    1989-01-01

    It is reported on an abnormally prolonged action of vecuronium in a female patient with known neurofibromatosis (Morbus von Recklinghausen). In this female patient an increased sensitivity to vecuronium (0.06 mg/kg) was observed during anaesthesia for Caesarean section. A 100% block lasted 50 minutes and the neuromuscular recovery from 75% block to 25% block amounted to 25 minutes. This prolonged neuromuscular block can also be due to overdosing, relative hypovolaemia during arterial hypertension and the previous application of suxamethonium. PMID:2568840

  11. Kosteneffiziente Honbearbeitung durch intelligente und flexible Verknüpfung von autarken Honzentren

    NASA Astrophysics Data System (ADS)

    Roth, Günther

    Die Planungsabteilungen in der Automobilindustrie werden vor immer größere Herausforderungen gestsellt. Der zur Verfügung stehende Zeitraum zu einer seriensicheren Umsetzung der entwicklungs- und produktionstechnischen Forderungen wird von Projekt zu Projekt kürzer. Aufgrund des hohen Wettbewerbsdrucks und daraus resultierenden erforderlichen Kostenoptimierungen, die schnelleren Timeto-market-und Innovationszyklen und die vermeintlich zur Kundenbindung erforderlichen, kaum mehr überschaubaren Diversifizierungen in den Modellpaletten lassen den Planungshorizont immer kürzer werden. Die zu beschaffenden Fertigungsanlagen sollen aber in den nächsten 8-12 Jahren all die Varianten produzieren können, die heute nur teilweise oder noch gar nicht bekannt sind.

  12. Otto von Guericke and 17th century cosmology

    NASA Astrophysics Data System (ADS)

    Knobloch, Eberhard

    Otto von Guericke's scientific method was based on reason and experimental science. His cosmology was embedded in theology and can be interpreted as a refutation of Descartes' worldview. He used Nicolaus Cusanus' theory of quantities in order to characterize space. The notion of space has to be distinguished from that of world or heaven. Forces play a crucial role in this respect described by Athanasius Kircher in his "Celestial Journey". Guericke read this work very diligently. In spite of some obvious similarities between Guericke's and Newton's scientific aims and methods there are crucial differences between the scientific convictions and results of these scholars.

  13. von Kármán Vortex Street within an Impacting Drop

    NASA Astrophysics Data System (ADS)

    Thoraval, Marie-Jean; Takehara, Kohsei; Etoh, Takeharu Goji; Popinet, Stéphane; Ray, Pascal; Josserand, Christophe; Zaleski, Stéphane; Thoroddsen, Sigurdur T.

    2012-06-01

    The splashing of a drop impacting onto a liquid pool produces a range of different sized microdroplets. At high impact velocities, the most significant source of these droplets is a thin liquid jet emerging at the start of the impact from the neck that connects the drop to the pool. We use ultrahigh-speed video imaging in combination with high-resolution numerical simulations to show how this ejecta gives way to irregular splashing. At higher Reynolds numbers, its base becomes unstable, shedding vortex rings into the liquid from the free surface in an axisymmetric von Kármán vortex street, thus breaking the ejecta sheet as it forms.

  14. Karl Ernst von Baer (1792-1876) and evolution.

    PubMed

    Brauckmann, Sabine

    2012-01-01

    The research program of Karl Ernst von Baer (1792-1876) intended to enhance the comparative approach of animal classification by demonstrating vertebrate affinities (homology). Baer visualized his ideas on development and evolution with an unpublished figure of a branching tree. To buttress his reflections on how species-specific embryogenesis produces a branching tree, he worked out a cladogram-like chart, depicting the ontogeny and phylogeny of vertebrate embryos. For Baer, changes in development were responsible for changes in phenotype. I will offer a new interpretation of Baer's ideas about evolution showing that he believed in the transformation of species and announced such views publicly. PMID:23319342

  15. Botschaften aus einer fernen Welt. Landung von Huygens auf Titan ein voller Erfolg

    NASA Astrophysics Data System (ADS)

    Althaus, Tilmann

    2005-03-01

    Am 14. Januar 2005 trat die europäische Raumsonde Huygens in die dichte Gashülle des größten Saturnmonds Titan ein und sendete von dort zahlreiche Messdaten und Bilder zur Erde. Wie sich die kurze Mission von Huygens auf der Erde im Kontrollzentrum ESOC in Darmstadt darstellte, davon handelt dieser Bericht.

  16. Giant cell tumor of the occipital bone in a case of von Recklinghausen neurofibromatosis.

    PubMed

    Opitz, H; Petersen, D; Heiss, E; Duffner, F; Meyermann, R

    1996-01-01

    Von Recklinghausen neurofibromatosis (NF1) is the most common hereditary syndrome predisposing to neoplasia. The most common symptomatic manifestation of NF1 is the plexiform neurofibroma. We describe the case of a patient with classical von Recklinghausen neurofibromatosis presenting with a giant cell tumor (GCT) of the occipital bone infiltrating a surrounding plexiform neurofibroma. PMID:8836608

  17. Dr. von Braun with the Front Page of the Huntsville Times

    NASA Technical Reports Server (NTRS)

    1963-01-01

    Dr. von Braun is presented with the front page of the Huntsville Times arnouncing the launch of Explorer I, the first U.S. Earth satellite, which was boosted by the Jupiter-C launch vehicle developed by Army Ballistic Missile Agency (ABMA) under the direction of Dr. von Braun. The occasion was the fifth Anniversary of the Explorer I launch in January 1958.

  18. [Correspondence between Winkler and Von Monakow. I. Personal affairs and visions].

    PubMed

    Koehler, P J; Jagella, C

    2001-12-22

    Cornelis Winkler (1855-1941) and Constantin von Monakow (1853-1930) are considered to be pioneers in neurology in the Netherlands and Switzerland respectively. Winkler became the first professor of Psychiatry and Neurology in Utrecht (1893) and Von Monakow the first professor of Neurology in Zürich (1894). They first met in Amsterdam (1907). Many other meetings followed and they maintained a lively correspondence. Winkler's letters to Von Monakow (1908-1927) are archived at the Institute of Medical History in Zürich and are the principal source for two articles. This first article considers personal affairs and views: the friendly relationship, the experiences during World War I, the personal struggle with respect to the emancipation of neurology at the start of the 19th century, Von Monakow's manuscript of Vita Mea and finally Von Monakow's succession. PMID:11789152

  19. Klassifikation von Standardebenen in der 2D-Echokardiographie mittels 2D-3D-Bildregistrierung

    NASA Astrophysics Data System (ADS)

    Bergmeir, Christoph; Subramanian, Navneeth

    Zum Zweck der Entwicklung eines Systems, das einen unerfahrenen Anwender von Ultraschall (US) zur Aufnahme relevanter anatomischer Strukturen leitet, untersuchen wir die Machbarkeit von 2D-US zu 3D-CT Registrierung. Wir verwenden US-Aufnahmen von Standardebenen des Herzens, welche zu einem 3D-CT-Modell registriert werden. Unser Algorithmus unterzieht sowohl die US-Bilder als auch den CT-Datensatz Vorverarbeitungsschritten, welche die Daten durch Segmentierung auf wesentliche Informationen in Form von Labein für Muskel und Blut reduzieren. Anschließend werden diese Label zur Registrierung mittels der Match-Cardinality-Metrik genutzt. Durch mehrmaliges Registrieren mit verschiedenen Initialisierungen ermitteln wir die im US-Bild sichtbare Standardebene. Wir evaluierten die Methode auf sieben US-Bildern von Standardebenen. Fünf davon wurden korrekt zugeordnet.

  20. von Baer's law for the ages: lost and found principles of developmental evolution.

    PubMed

    Abzhanov, Arhat

    2013-12-01

    In 1828, Karl Ernst von Baer formulated a series of empirically defined rules, which became widely known as the 'Law of Development' or 'von Baer's law of embryology'. This was one the most significant attempts to define the principles that connected morphological complexity and embryonic development. Understanding this relation is central to both evolutionary biology and developmental genetics. Von Baer's ideas have been both a source of inspiration to generations of biologists and a target of continuous criticism over many years. With advances in multiple fields, including paleontology, cladistics, phylogenetics, genomics, and cell and developmental biology, it is now possible to examine carefully the significance of von Baer's law and its predictions. In this review, I argue that, 185 years after von Baer's law was first formulated, its main concepts after proper refurbishing remain surprisingly relevant in revealing the fundamentals of the evolution-development connection, and suggest that their explanation should become the focus of renewed research. PMID:24120296

  1. Karl ernst von Baer's 'Uber Entwickelungsgeschichte der Thiere II' and its unpublished drawings.

    PubMed

    Tammiksaar, Erki; Brauckmann, Sabine

    2004-01-01

    In 1828 Karl Ernst von Baer (1792-1876) published his seminal Uber Entwickelungsgeschichte der Thiere. Beobachtung und Reflexion. In the preface he announced that a second volume with one copper plate would be finished 'in a few weeks'. However, it took nine years until the unfinished second volume was released, with four copperplates. In his 'Autobiography', von Baer did not clarify the reasons why he did not finish his research program of comparative embryology. The paper attempts to elucidate them, furnished by archival documents and von Baer's unpublished embryological drawings. Our sketch of a few figures will show that (1) von Baer searched for 'analogies' (homologies) as a unifying principle and (2) explained the mechanisms of embryogenesis by physiological reasoning (electromagnetism). The main objective is to show that technical problems in illustrating and conceptual difficulties impeded von Baer's ambitious research program. PMID:16302690

  2. Evaluation of von Willebrand factor during pregnancy, lactation and oestrous cycle in bitches affected and unaffected by von Willebrand disease.

    PubMed

    Mattoso, C R S; Takahira, R K; Beier, S L; Araujo, J P; Corrente, J E

    2013-06-01

    Plasmatic concentrations of von Willebrand Factor (vWF) increase during pregnancy in humans and dogs; however the mechanism of such increase is still not well defined. The aims of this study were: (i) to evaluate changes in vWF concentration during pregnancy and during the subsequent oestrous cycle in bitches affected and unaffected by von Willebrand Disease (vWD); (ii) to correlate the vWF levels and cortisol levels in both groups. Seven vWD affected (GI) and nine unaffected (GII) bitches were used. The animals were assessed during pregnancy, parturition, lactation and non-gestational oestrous cycle in 11 moments (Pregnancy 1, Pregnancy 2, Parturition, Lactation 1, Lactation 2, Lactation 3, Anestrus, Proestrus, Oestrus, Diestrus 1, and Diestrus 2). The following tests were performed; measurement of von Willebrand factor antigen (vWF:Ag), albumin and cortisol. In both groups, vWF concentration remained stable during the non-gestational oestrous cycle, but increased during pregnancy, with the highest value observed at parturition. Increases of 70% and 124% in vWF were seen in GI and GII, respectively, compared to anestrus. No correlation was found between vWF and cortisol. Values of vWF:Ag changed during pregnancy, with a peak at parturition, both in vWD affected and unaffected animals. Values of vWF were not altered in the different phases of the oestrous cycle following pregnancy in both groups. Evaluation of vWF during pregnancy can cause false negative results for vWD, but assessment can be performed at any point in the oestrous cycle of non-pregnant bitches. PMID:23035816

  3. Zum Gefrieren von Wasser in porösen Festkörpern, Glas- oder Phasenübergang?

    NASA Astrophysics Data System (ADS)

    Pfeifer, H.; Oehme, W.; Siegel, H.

    In der vorliegenden Arbeit werden poröse Festkörper mit definierten Hohlraumstrukturen und homogener innerer Oberfläche (Sauerstoffatome bei Zeolithen und porösen Gläsern) verwendet, um das Gefrieren von Aggregaten bestehend aus wenigen Wassermolekülen experimentell zu untersuchen. Es zeigt sich, daß Aggregate mit weniger als etwa fünf Wassermolekülen beim Abkühlen ohne Strukturänderung erstarren (Glasübergang), während für etwa zehn bis dreißig Wassermoleküle die Ergebnisse von Molwärme- und magnetischen Protonenresonanzmessungen mit einer semiempirischen Theorie durch einen diffusen Phasenübergang 1. Ordnung und mehr oder weniger stark reduzierter integraler Schmelzwärme erklärt werden können.Translated AbstractFreezing of Water in Porous Solids, Glass Transition or Phase Transition?This paper is concerned with the freezing of small water aggregates in solids with a homogeneous pore distribution and a homogeneous interior surface (oxygen atoms for zeolites and porous glasses). Aggregates containing less than about five water molecules freeze without any change in their structure (glass transition). However, molar heat and proton magnetic resonance studies on aggregates of about ten to thirty water molecules could be explained by a diffuse phase transition of first order with a more or less strongly reduced integral melting heat.

  4. The von Neumann model of measurement in quantum mechanics

    SciTech Connect

    Mello, Pier A.

    2014-01-08

    We describe how to obtain information on a quantum-mechanical system by coupling it to a probe and detecting some property of the latter, using a model introduced by von Neumann, which describes the interaction of the system proper with the probe in a dynamical way. We first discuss single measurements, where the system proper is coupled to one probe with arbitrary coupling strength. The goal is to obtain information on the system detecting the probe position. We find the reduced density operator of the system, and show how Lüders rule emerges as the limiting case of strong coupling. The von Neumann model is then generalized to two probes that interact successively with the system proper. Now we find information on the system by detecting the position-position and momentum-position correlations of the two probes. The so-called 'Wigner's formula' emerges in the strong-coupling limit, while 'Kirkwood's quasi-probability distribution' is found as the weak-coupling limit of the above formalism. We show that successive measurements can be used to develop a state-reconstruction scheme. Finally, we find a generalized transform of the state and the observables based on the notion of successive measurements.

  5. Von Braun Rocket Team at Fort Bliss, Texas

    NASA Technical Reports Server (NTRS)

    1940-01-01

    The German Rocket Team, also known as the Von Braun Rocket Team, poses for a group photograph at Fort Bliss, Texas. After World War II ended in 1945, Dr. Wernher von Braun led some 120 of his Peenemuende Colleagues, who developed the V-2 rocket for the German military during the War, to the United Sttes under a contract to the U.S. Army Corps as part of Operation Paperclip. During the following five years the team worked on high altitude firings of the captured V-2 rockets at the White Sands Missile Range in New Mexico, and a guided missile development unit at Fort Bliss, Texas. In April 1950, the group was transferred to the Army Ballistic Missile Agency (ABMA) at Redstone Arsenal in Huntsville, Alabama, and continued to work on the development of the guided missiles for the U.S. Army until transferring to a newly established field center of the National Aeronautic and Space Administration (NASA), George C. Marshall Space Flight Center (MSFC).

  6. von Willebrand factor, Jedi knight of the bloodstream.

    PubMed

    Springer, Timothy A

    2014-08-28

    When blood vessels are cut, the forces in the bloodstream increase and change character. The dark side of these forces causes hemorrhage and death. However, von Willebrand factor (VWF), with help from our circulatory system and platelets, harnesses the same forces to form a hemostatic plug. Force and VWF function are so closely intertwined that, like members of the Jedi Order in the movie Star Wars who learn to use "the Force" to do good, VWF may be considered the Jedi knight of the bloodstream. The long length of VWF enables responsiveness to flow. The shape of VWF is predicted to alter from irregularly coiled to extended thread-like in the transition from shear to elongational flow at sites of hemostasis and thrombosis. Elongational force propagated through the length of VWF in its thread-like shape exposes its monomers for multimeric binding to platelets and subendothelium and likely also increases affinity of the A1 domain for platelets. Specialized domains concatenate and compact VWF during biosynthesis. A2 domain unfolding by hydrodynamic force enables postsecretion regulation of VWF length. Mutations in VWF in von Willebrand disease contribute to and are illuminated by VWF biology. I attempt to integrate classic studies on the physiology of hemostatic plug formation into modern molecular understanding, and point out what remains to be learned. PMID:24928861

  7. Attractors and Long Time Behavior of von Karman Thermoelastic Plates

    SciTech Connect

    Chueshov, Igor Lasiecka, Irena

    2008-10-15

    This paper undertakes a study of asymptotic behavior of solutions corresponding to von Karman thermoelastic plates. A distinct feature of the work is that the model considered has no added dissipation-particularly mechanical dissipation typically added to plate equation when long time-behavior is considered. Thus, the model consists of undamped oscillatory plate equation strongly coupled with heat equation. Nevertheless we are able to show that the ultimate (asymptotic) behavior of the von Karman evolution is described by finite dimensional global attractor. In addition, the obtained estimate for the dimension and the size of the attractor are independent of the rotational inertia parameter {gamma} and heat/thermal capacity {kappa}, where the former is known to change the character of dynamics from hyperbolic ({gamma}>0) to parabolic like ({gamma}=0). Other properties of attractors such as additional smoothness and upper-semicontinuity with respect to parameters {gamma} and {kappa} are also established. The main ingredients of the proofs are (i) sharp regularity of Airy's stress function, and (ii) newly developed (Chueshov and Lasiecka in Memoirs of AMS, in press) 'compensated' compactness methods applicable to non-compact dynamics.

  8. Von Hippel-Lindau disease in a pregnant lady.

    PubMed

    Choudhury, T; Jahan, S; Kamal, M; Hossain, M M; Khan, Z R

    2012-01-01

    Von Hippel-Lindau disease is a rare genetic disorder characterized by various tumours and cysts in the central nervous system and other viscera. Here a case was described in a young female who was pregnant at the time of initial presentation with the complaints of occasional headache, low back pain and pain in the upper abdomen. After the birth of a healthy baby she was admitted to the hospital and the CT scan of upper abdomen suggested a multiloculated pancreatic cyst. MRI of thoracolumbar spine revealed an intracanalicular extradural mass and CT scan of brain revealed a cerebellar cystic mass. The spinal and cerebellar masses both were diagnosed histologically as haemangioblastoma. After a month she underwent laparotomy with near total pancreatectomy. Microscopically it was a microcystic cystadenoma. Based on the clinical presentation, imaging and histopathology of spinal, cerebellar and pancreatic lesions as well as a family history of her father's death due to brain tumour the final diagnosis was Von Hippel-Lindau disease. PMID:22314480

  9. von Willebrand factor, Jedi knight of the bloodstream

    PubMed Central

    2014-01-01

    When blood vessels are cut, the forces in the bloodstream increase and change character. The dark side of these forces causes hemorrhage and death. However, von Willebrand factor (VWF), with help from our circulatory system and platelets, harnesses the same forces to form a hemostatic plug. Force and VWF function are so closely intertwined that, like members of the Jedi Order in the movie Star Wars who learn to use “the Force” to do good, VWF may be considered the Jedi knight of the bloodstream. The long length of VWF enables responsiveness to flow. The shape of VWF is predicted to alter from irregularly coiled to extended thread-like in the transition from shear to elongational flow at sites of hemostasis and thrombosis. Elongational force propagated through the length of VWF in its thread-like shape exposes its monomers for multimeric binding to platelets and subendothelium and likely also increases affinity of the A1 domain for platelets. Specialized domains concatenate and compact VWF during biosynthesis. A2 domain unfolding by hydrodynamic force enables postsecretion regulation of VWF length. Mutations in VWF in von Willebrand disease contribute to and are illuminated by VWF biology. I attempt to integrate classic studies on the physiology of hemostatic plug formation into modern molecular understanding, and point out what remains to be learned. PMID:24928861

  10. Quantitative Hyperspectral Reflectance Imaging

    PubMed Central

    Klein, Marvin E.; Aalderink, Bernard J.; Padoan, Roberto; de Bruin, Gerrit; Steemers, Ted A.G.

    2008-01-01

    Hyperspectral imaging is a non-destructive optical analysis technique that can for instance be used to obtain information from cultural heritage objects unavailable with conventional colour or multi-spectral photography. This technique can be used to distinguish and recognize materials, to enhance the visibility of faint or obscured features, to detect signs of degradation and study the effect of environmental conditions on the object. We describe the basic concept, working principles, construction and performance of a laboratory instrument specifically developed for the analysis of historical documents. The instrument measures calibrated spectral reflectance images at 70 wavelengths ranging from 365 to 1100 nm (near-ultraviolet, visible and near-infrared). By using a wavelength tunable narrow-bandwidth light-source, the light energy used to illuminate the measured object is minimal, so that any light-induced degradation can be excluded. Basic analysis of the hyperspectral data includes a qualitative comparison of the spectral images and the extraction of quantitative data such as mean spectral reflectance curves and statistical information from user-defined regions-of-interest. More sophisticated mathematical feature extraction and classification techniques can be used to map areas on the document, where different types of ink had been applied or where one ink shows various degrees of degradation. The developed quantitative hyperspectral imager is currently in use by the Nationaal Archief (National Archives of The Netherlands) to study degradation effects of artificial samples and original documents, exposed in their permanent exhibition area or stored in their deposit rooms.

  11. Variable content of von Willebrand factor mutant monomer drives the phenotypic variability in a family with von Willebrand disease.

    PubMed

    Chen, Junmei; Hinckley, Jesse D; Haberichter, Sandra; Jacobi, Paula; Montgomery, Robert; Flood, Veronica H; Wong, Randall; Interlandi, Gianluca; Chung, Dominic W; López, José A; Di Paola, Jorge

    2015-07-01

    Von Willebrand disease (VWD) is an inherited bleeding disorder characterized by incomplete penetrance and variable expressivity. We evaluated a 24-member pedigree with VWD type 2 caused by a T>G mutation at position 3911 that predicts a methionine to arginine (M1304R) change in the platelet-binding A1 domain of von Willebrand factor (VWF). This mutation manifests as an autosomal-dominant trait, with clinical and biochemical phenotypic variability among affected individuals, including differences in bleeding tendency and VWF quantity, activity, and multimer pattern. Sequencing of all VWF coding regions in 3 affected individuals did not identify additional mutations. When expressed in heterologous cells, M1304R was secreted in lower quantities, failed to drive formation of storage granules, and was defective in multimerization and platelet binding. When cotransfected in equal quantities with the wild-type complementary DNA, the mutant complementary DNA depressed VWF secretion, although multimerization was only mildly affected. A llama nanobody (AU/VWFa-11) that detects the mutant A1 domain demonstrated highly variable binding to VWF from different affected members, indicating that the VWF contained different percentages of mutant monomers in different individuals. Thus, the observed variability in VWD phenotypes could in part be determined by the extent of mutant monomer incorporation in the final multimer structure of plasma VWF. PMID:26019279

  12. Mutations in the D1 domain of von Willebrand factor impair their propeptide-dependent multimerization, intracellular trafficking and secretion.

    PubMed

    Yin, Jie; Ma, Zhenni; Su, Jian; Wang, Jiong-Wei; Zhao, Xiaojuan; Ling, Jing; Bai, Xia; Ouyang, Wanyan; Wang, Zhaoyue; Yu, Ziqiang; Ruan, Changgeng

    2015-01-01

    We identified three novel mutations (p.Gly39Arg, p.Lys157Glu, p.Cys379Gly) and one previously known mutation (p.Asp141Asn) in the von Willebrand factor propeptide from three von Willebrand disease patients. All four mutations impaired multimerization of von Willebrand factor, due to reduced oxidoreductase activity of isomeric propeptide. These mutations resulted in the endothelial reticulum retention and impaired basal and stimulated secretions of von Willebrand factor. Our results support that the mutations in the D1 domain lead to defective multimerization, intracellular trafficking, and secretion of von Willebrand factor and result in bleeding of patients. PMID:26088471

  13. von Willebrand factor mutation enhancing interaction with platelets in patients with normal multimeric structure.

    PubMed Central

    Holmberg, L; Dent, J A; Schneppenheim, R; Budde, U; Ware, J; Ruggeri, Z M

    1993-01-01

    Variant von Willebrand disease designated as type I New York or type Malmö is characterized by enhanced ristocetin-induced platelet agglutination with normal von Willebrand factor multimeric distribution in plasma. We have studied four such patients belonging to three unrelated families and found in all of them a unique cytosine-to-thymine transition changing the codon for Pro503 (CCG) to Leu (CTG). In three patients the mutant allele also had a silent mutation in the codon for Ser500 (TCG-->TCA). Both nucleotide changes are present in the von Willebrand factor pseudogene; however, the characterization of distinctive markers where the gene and pseudogene differ, as well as the examination of amplified cDNA derived from platelet mRNA, confirmed that the abnormality occurs in the von Willebrand factor gene of the patients. Moreover, recombinant expression of the isolated glycoprotein Ib-binding domain of von Willebrand factor provided direct evidence that the Pro503-->Leu mutation is responsible for enhanced platelet reactivity to lower ristocetin concentrations. These results define a new structural element affecting the affinity of von Willebrand factor for glycoprotein Ib and establish the molecular basis of a variant form of von Willebrand disease. Images PMID:8486782

  14. Nature of von Willebrand factor: a new assay and a specific inhibitor.

    PubMed

    Sarji, K E; Stratton, R D; Wagner, R H; Brinkhous, K M

    1974-08-01

    Platelet-active "von Willebrand factor" is a poorly characterized activity of a plasma-protein macromolecular complex. A new simple assay for von Willebrand factor is based on the dose response relation of the factor and the ristocetin platelet aggregation time. This assay uses the "snowstorm" macroscopic endpoint. A multiply transfused subject with von Willebrand's disease was observed to have a circulating inhibitor that blocks normal ristocetin aggregation of platelets, but not ADP-, epinephrine-, or collagen-induced aggregation. The inhibitor was not adsorbed by normal platelets, and was stable to heating at 56 degrees for 30 min and to repeated freezings and thawings. This inhibitor also prevents action on human platelets by platelet-aggregating factor of bovine plasma, indicating this bovine factor activity is a function of von Willebrand factor. Three inhibitors were compared: (1) the von Willebrand factor inhibitor specifically blocked von Willebrand factor activity, (2) a human antibody from a hemophiliac inhibited only antihemophilic factor activity, and (3) a rabbit antiserum to a preparation of human antihemophilic factor inhibited both activities. The active site for von Willebrand factor on the macromolecular complex appears to be spaced some distance from the antihemophilic factor site. PMID:4547258

  15. Assessment of long-term habituation correlates in event-related potentials using a von Mises model.

    PubMed

    Mortezapouraghdam, Z; Haab, L; Corona-Strauss, F I; Steidl, G; Strauss, D J

    2015-05-01

    In our preliminary work we were able to demonstrate habituation by analyzing attention correlates in single-trial sequences of auditory event-related potentials (ERPs). Despite different quantitative studies of instantaneous phase of ERPs in long-term habituation, there have been no former studies in generative process underlying the distribution of instantaneous phase information in the context of long-term habituation and its relation to attentional binding. For this means we used a von Mises model, representing the phase information over a set of single trial responses. Additionally we use a quantitative neurofunctional model to predict the dynamics of the instantaneous phase in single-trial ERP data during the long-term habituation. Measured habituation data is used to cross-validate the model's prediction. We conclude that the described method allows for an assessment of dynamic changes in the course of long-term habituation. The results also reinforce our neurofunctional multiscale model of long-term habituation and show the applicability of the described method for the experimental/clinical neurodiagnostic assessment of attentional binding. PMID:25361510

  16. Quantitative evolutionary design

    PubMed Central

    Diamond, Jared

    2002-01-01

    The field of quantitative evolutionary design uses evolutionary reasoning (in terms of natural selection and ultimate causation) to understand the magnitudes of biological reserve capacities, i.e. excesses of capacities over natural loads. Ratios of capacities to loads, defined as safety factors, fall in the range 1.2-10 for most engineered and biological components, even though engineered safety factors are specified intentionally by humans while biological safety factors arise through natural selection. Familiar examples of engineered safety factors include those of buildings, bridges and elevators (lifts), while biological examples include factors of bones and other structural elements, of enzymes and transporters, and of organ metabolic performances. Safety factors serve to minimize the overlap zone (resulting in performance failure) between the low tail of capacity distributions and the high tail of load distributions. Safety factors increase with coefficients of variation of load and capacity, with capacity deterioration with time, and with cost of failure, and decrease with costs of initial construction, maintenance, operation, and opportunity. Adaptive regulation of many biological systems involves capacity increases with increasing load; several quantitative examples suggest sublinear increases, such that safety factors decrease towards 1.0. Unsolved questions include safety factors of series systems, parallel or branched pathways, elements with multiple functions, enzyme reaction chains, and equilibrium enzymes. The modest sizes of safety factors imply the existence of costs that penalize excess capacities. Those costs are likely to involve wasted energy or space for large or expensive components, but opportunity costs of wasted space at the molecular level for minor components. PMID:12122135

  17. von Willebrand factor binds to the surface of dendritic cells and modulates peptide presentation of factor VIII.

    PubMed

    Sorvillo, Nicoletta; Hartholt, Robin B; Bloem, Esther; Sedek, Magdalena; Brinke, Anja Ten; van der Zwaan, Carmen; van Alphen, Floris P; Meijer, Alexander B; Voorberg, Jan

    2016-03-01

    It has been proposed that von Willebrand factor might affect factor VIII immunogenicity by reducing factor VIII uptake by antigen presenting cells. Here we investigate the interaction of recombinant von Willebrand factor with immature monocyte-derived dendritic cells using flow cytometry and confocal microscopy. Surprisingly, von Willebrand factor was not internalized by immature dendritic cells, but remained bound to the cell surface. As von Willebrand factor reduces the uptake of factor VIII, we investigated the repertoire of factor VIII presented peptides when in complex with von Willebrand factor. Interestingly, factor VIII-derived peptides were still abundantly presented on major histocompatibility complex class II molecules, even though a reduction of factor VIII uptake by immature dendritic cells was observed. Inspection of peptide profiles from 5 different donors showed that different core factor VIII peptide sequences were presented upon incubation with factor VIII/von Willebrand factor complex when compared to factor VIII alone. No von Willebrand factor peptides were detected when immature dendritic cells were pulsed with different concentrations of von Willebrand factor, confirming lack of von Willebrand factor endocytosis. Several von Willebrand factor derived peptides were recovered when cells were pulsed with von Willebrand factor/factor VIII complex, suggesting that factor VIII promotes endocytosis of small amounts of von Willebrand factor by immature dendritic cells. Taken together, our results establish that von Willebrand factor is poorly internalized by immature dendritic cells. We also show that von Willebrand factor modulates the internalization and presentation of factor VIII-derived peptides on major histocompatibility complex class II. PMID:26635035

  18. von Zeipel surfaces and convective instability of accretion discs in modified gravity

    NASA Astrophysics Data System (ADS)

    Alipour, N.; Khesali, A. R.; Nozari, K.

    2015-12-01

    It is assumed that von Zeipel surfaces would play an important role in determining the structure and stability properties of equilibrium configuration of a barotropic fluid. The present study has investigated von Zeipel surfaces and instability of an accretion disc in modified gravity. The findings show that in the framework of modified gravity, the rate of mass accretion in an accretion disc is larger in the inner edge, middle region and the outer edge of the accretion disc much in the same way. However, in the scale of Solar system, von Zeipel surfaces with modified gravity are similar to the standard case.

  19. Robuste Verzweigungserkennung von Gefäßen in CTA-Datensätzen zur modellbasierten Extraktion der Centerline

    NASA Astrophysics Data System (ADS)

    Beck, Thomas; Fritz, Dominik; Biermann, Christina; Dillmann, Rüdiger

    Bei der Befundung und Visualisierung von Blutgefäßen ist deren Centerline von zentraler Bedeutung. Die Unterscheidung zwischen unverzweigten Abschnitten des Gefäßes und Verzweigungsbereichen ermöglicht den Einsatz spezialisierter und sehr effizienter Algorithmen zur modellbasierten Extraktion der Centerline. In diesem Artikel wird ein robustes Verfahren zur Verzweigungserkennung vorgestellt. Das Verfahren beruht auf einem Front-Propagation-Ansatz mit dynamisch angepassten Schwellwerten und einer anschließenden Clusteranalyse. Die vorgestellte Methode zur Verzweigungserkennung wurde als Komponente einer Architektur zur Extraktion der Centerline auf handannotierten Datensätzen getestet. Erste Ergebnisse sind sehr vielversprechend und ermöglichen auch bei pathologischen Gefäßen eine robuste Detektion von Gefäßverzweigungen.

  20. On conjugate families and Jeffreys priors for von Mises–Fisher distributions

    PubMed Central

    Hornik, Kurt; Grün, Bettina

    2013-01-01

    This paper discusses characteristics of standard conjugate priors and their induced posteriors in Bayesian inference for von Mises–Fisher distributions, using either the canonical natural exponential family or the more commonly employed polar coordinate parameterizations. We analyze when standard conjugate priors as well as posteriors are proper, and investigate the Jeffreys prior for the von Mises–Fisher family. Finally, we characterize the proper distributions in the standard conjugate family of the (matrix-valued) von Mises–Fisher distributions on Stiefel manifolds. PMID:23805026

  1. [Ernst von der Porten : looking for facts before and after forced emigration].

    PubMed

    Goerig, M; Bruijn, L

    2014-10-01

    The Ernst von der Porten medal has been awarded for many years to exceptional personalities by the Alliance of German Anesthesiologists to honor the outstanding achievements of the physician Ernst von der Porten from Hamburg in the development of anesthesiology as an autonomous discipline Only recent access to hitherto inaccessible documents enabled the reconstruction of his final years. He was persecuted and excluded by the National Socialist (NS) regime due to his Jewish roots and finally forced to emigrate. Records revealed that even in the so-called safe exile, degrading treatment and humiliation continued for Ernst von der Porten and his family. He eventually evaded this situation by committing suicide. PMID:25185861

  2. Voluntarism in early psychology: the case of Hermann von Helmholtz.

    PubMed

    De Kock, Liesbet

    2014-05-01

    The failure to recognize the programmatic similarity between (post-)Kantian German philosophy and early psychology has impoverished psychology's historical self-understanding to a great extent. This article aims to contribute to recent efforts to overcome the gaps in the historiography of contemporary psychology, which are the result of an empiricist bias. To this end, we present an analysis of the way in which Hermann von Helmholtz's theory of perception resonates with Johann Gottlieb Fichte's Ego-doctrine. It will be argued that this indebtedness is particularly clear when focusing on the foundation of the differential awareness of subject and object in perception. In doing so, the widespread reception of Helmholtz's work as proto-positivist or strictly empiricist is challenged, in favor of the claim that important elements of his theorizing can only be understood properly against the background of Fichte's Ego-doctrine. PMID:24818740

  3. Using genetic diagnostics in hemophilia and von Willebrand disease.

    PubMed

    Swystun, Laura L; James, Paula

    2015-12-01

    Most bleeding disorders encountered in clinical practice will be diagnosed, at least initially, by phenotypic assays. However, since the characterization of the genes that encode coagulation factors in the 1980s, significant progress has been made in translating this knowledge for diagnostic and therapeutic purposes. For hemophilia A and B, molecular genetic testing to determine carrier status, prenatal diagnosis, and likelihood of inhibitor development or anaphylaxis to infused coagulation factor concentrates is an established component of comprehensive clinical management. In contrast, although significant recent advances in our understanding of the molecular genetic basis of von Willebrand disease (VWD) have allowed for the development of rational approaches to genetic diagnostics, questions remain about this complex genetic disorder and how to incorporate emerging knowledge into diagnostic strategies. This article will review the state-of-the-art for molecular diagnostics for both hemophilia and VWD. PMID:26637715

  4. Franz von Leydig (1821-1908), pioneer of comparative histology.

    PubMed

    Schneider, Marlon R

    2012-05-01

    Franz von Leydig, a German histologist and zoologist, is known to every student of human or animal anatomy because of the testicular testosterone-producing cells carrying his name. However, he made many contributions to our knowledge of the fine structure of animal tissues, including more than 200 scientific articles and several books. His most important work, the book Lehrbuch der Histologie des Menschen und der Thiere, established him as a pioneer if not the founder of comparative histology. Leydig taught at three different universities (Würzburg, Tübingen and Bonn) and received many honours from scientific organizations worldwide, including the Royal Society. He died in Rothenburg ob der Tauber, the town of his birth, aged 86 years. PMID:22791874

  5. von Karman Vortex Streets Generated by Different Shaped Rods

    NASA Astrophysics Data System (ADS)

    Kim, Ildoo; Cerbus, Rory; Wu, Xiao-Lun

    2008-03-01

    von Karman vortex street is a pattern of vortices behind a bluff body in a uniform stream. Strouhal number St, a non-dimensional frequency of vortex shedding, depends on Reynolds number Re, however the precise relationship is not known although there were several proposals. To test these proposals and to investigate the nature of vortex shedding, we have generated Karman vortex streets in two-dimensional soap film using conic bodies with different croess-sectional geometric shapes and orientations. We found that the structure-based St-Re relationship, St=1/(A+B/Re), is in good agreement with our experimental data using different shapes and orientations. Two coefficients A and B are functions of geometries and orientations of bluff bodies. Also, we found under certain conditions, two adjacent vortices merge into a big vortex downstream.

  6. Alexander von Humboldt's perceptions of colonial Spanish America.

    PubMed

    Rebok, Sandra

    2009-01-01

    This study presents an in-depth analysis of Alexander von Humboldt's descriptions and critical comments on the colonial society of the different regions he visited during his well-known expedition through the Americas (1799-1804). The criticisms of colonialism that he expressed, reflecting his personal convictions, have already been the focal point of many studies, but Humboldt also was able to offer a more differentiated assessment through comparisons of regional and local traditions and developments. This essay focuses on his personal diaries, which offer many interesting comments on colonial societies. These considerations and impressions made during the expedition are of particular scholarly value since they were not subject to censorship of any kind. PMID:19852391

  7. A Powerful Friendship: Theodore von Karman and Hugh L. Dryden

    NASA Technical Reports Server (NTRS)

    Gorn, Michael

    2003-01-01

    During their long personal friendship and professional association, Theodore von Karman (1882-1963) and Hugh L. Dryden (1898-1965) exercised a pivotal if somewhat elusive influence over American aeronautics and spaceflight. Both decisive figures in organizing scientists and engineers at home and abroad, both men of undisputed eminence in their technical fields, their range of contacts in government, academia, the armed forces, industry, and professional societies spanned the globe to an extent unparalleled then as now. Moreover, because they coordinated their activities closely, their combined influence far exceeded the sum of each one s individual contributions. This paper illustrates their personal origins as well as the foundations of their friendship, how their relationship became a professional alliance, and their joint impact on the world of aeronautics and astronautics during the twentieth century.

  8. Von Glaserfeld`s Radical Constructivism: A Critical Review

    NASA Astrophysics Data System (ADS)

    Hardy, Michael D.

    We explore Ernst von Glaserfelds radical constructivism, its criticisms, and our own thoughts on what it promises for the reform of science and mathematics teaching. Our investigation reveals that many criticisms of radical constructivism are unwarranted; nevertheless, in its current cognitivist form radical constructivism may be insufficient to empower teachers to overcome objectivist cultural traditions. Teachers need to be empowered with rich understandings of philosophies of science and mathematics that endorse relativist epistemologies; for without such they are unlikely to be prepared to reconstruct their pedagogical practices. More importantly, however, is a need for a powerful social epistemology to serve as a referent for regenerating the culture of science education. We recommend blending radical constructivism with Habermas theory of communicative action to provide science teachers with a moral imperative for adopting a constructivist epistemology.

  9. [Carl Friedrich von Weizsäcker's design of a unity of physics].

    PubMed

    Görnitz, Thomas

    2014-01-01

    As I learned in many conversations with Carl Friedrich von Weizsäcker, he saw his place in the history of science deriving from his "Theory of Urs". This theory will establish the unity of science on the basis of quantum bits. Any attempts to find some "fundamental bricks"--of whatever kind--must fail because of the antinomies of atomism. An abstract quantum bit is a structure quantum that cannot be conceived as a particle in space and time. However, it is clear, solely for logical reasons, that a quantum bit is an ultimate and indecomposable entity. Weizsäcker's revolutionary goal was--already 50 years ago--to unite quantum theory with cosmology and, on these grounds, proceed to a theory of elementary particles. The article gives a short overview of Weizsäcker's approach to the unity of physics, ending with a brief summary of what has been achieved in that endeavour up to now. PMID:24974600

  10. Ludwig von Bertalanffy's organismic view on the theory of evolution.

    PubMed

    Drack, Manfred

    2015-03-01

    Ludwig von Bertalanffy was a key figure in the advancement of theoretical biology. His early considerations already led him to recognize the necessity of considering the organism as a system, as an organization of parts and processes. He termed the resulting research program organismic biology, which he extended to all basic questions of biology and almost all areas of biology, hence also to the theory of evolution. This article begins by outlining the rather unknown (because often written in German) research of Bertalanffy in the field of theoretical biology. The basics of the organismic approach are then described. This is followed by Bertalanffy's considerations on the theory of evolution, in which he used methods from theoretical biology and then introduced his own, organismic, view on evolution, leading to the demand for finding laws of evolution. Finally, his view on the concept of homology is presented. PMID:25727202

  11. ADAMTS13 and von Willebrand Factor in Thrombotic Thrombocytopenic Purpura

    PubMed Central

    Zheng, X. Long

    2015-01-01

    Pathogenesis of thrombotic thrombocytopenic purpura (TTP) was a mystery for over half a century until the discovery of ADAMTS13. ADAMTS13 is primarily synthesized in the liver, and its main function is to cleave von Willebrand factor (VWF) anchored on the endothelial surface, in circulation, and at the sites of vascular injury. Deficiency of plasma ADAMTS13 activity (<10%) resulting from mutations of the ADAMTS13 gene or autoantibodies against ADAMTS13 causes hereditary or acquired (idiopathic) TTP. ADAMTS13 activity is usually normal or modestly reduced (>20%) in other forms of thrombotic microangiopathy secondary to hematopoietic progenitor cell transplantation, infection, and disseminated malignancy or in hemolytic uremic syndrome. Plasma infusion or exchange remains the initial treatment of choice to date, but novel therapeutics such as recombinant ADAMTS13 and gene therapy are under development. Moreover, ADAMTS13 deficiency has been shown to be a risk factor for the development of myocardial infarction, stroke, cerebral malaria, and preeclampsia. PMID:25587650

  12. SNAP23 Regulates Endothelial Exocytosis of von Willebrand Factor

    PubMed Central

    Zhu, Qiuyu; Yamakuchi, Munekazu; Lowenstein, Charles J.

    2015-01-01

    Endothelial exocytosis regulates vascular thrombosis and inflammation. The trafficking and release of endothelial vesicles is mediated by SNARE (Soluble NSF Attachment protein REceptors) molecules, but the exact identity of endothelial SNAREs has been unclear. Three SNARE molecules form a ternary complex, including isoforms of the syntaxin (STX), vesicle-associated membrane protein (VAMP), and synaptosomal-associated protein (SNAP) families. We now identify SNAP23 as the predominant endothelial SNAP isoform that mediates endothelial exocytosis of von Willebrand Factor (VWF). SNAP23 was localized to the plasma membrane. Knockdown of SNAP23 decreased endothelial exocytosis, suggesting it is important for endothelial exocytosis. SNAP23 interacted with the endothelial exocytic machinery, and formed complexes with other known endothelial SNARE molecules. Taken together, these data suggest that SNAP23 is a key component of the endothelial SNARE machinery that mediates endothelial exocytosis. PMID:26266817

  13. Stochastic resonance in a generalized Von Foerster population growth model

    SciTech Connect

    Lumi, N.; Mankin, R.

    2014-11-12

    The stochastic dynamics of a population growth model, similar to the Von Foerster model for human population, is studied. The influence of fluctuating environment on the carrying capacity is modeled as a multiplicative dichotomous noise. It is established that an interplay between nonlinearity and environmental fluctuations can cause single unidirectional discontinuous transitions of the mean population size versus the noise amplitude, i.e., an increase of noise amplitude can induce a jump from a state with a moderate number of individuals to that with a very large number, while by decreasing the noise amplitude an opposite transition cannot be effected. An analytical expression of the mean escape time for such transitions is found. Particularly, it is shown that the mean transition time exhibits a strong minimum at intermediate values of noise correlation time, i.e., the phenomenon of stochastic resonance occurs. Applications of the results in ecology are also discussed.

  14. Zu Newtons Erde-Mond-Test von 1665/66

    NASA Astrophysics Data System (ADS)

    Richter, G.

    Newtons Erde-Mond-Test zur Frage, ob die Schwerkraft der Erde, welche frei fallenden Körpern nahe der Erdoberfläche eine Beschleunigung von g 982 cm sec-2 erteilt, bei Annahme ihrer Abschwächung mit dem inversen Quadrat der Entfernung vom Erdmittelpunkt die beim Umlauf des Mondes um die Erde entstehende Zentrifugalkraft exakt kompensiert, wird im folgenden mit neueren Beobachtungsdaten über g, die Erddimensionen sowie die astronomischen Konstanten der Mondbahn erneut diskutiert.Bei Berücksichtigung der Störung der Mondbewegung durch die Sonne ergibt sich bereits in erster Näherung, daß das Verhältnis der Massen von Mond und Erde nahe bei 1:81 liegen muß, wenn als mittlere Mondentfernung der konventionelle Wert 384400 km zugrunde gelegt wird.Translated AbstractOn Newton's Earth-Moon-Test of 1665/66Newton's proof on the earth-moon-system - whether the gravitation of the earth which gives freely falling bodies near the earth's surface an acceleration of g 982 cm/sec2 and decreasing proportional to the inverse square of the distance from the earth's centre fully compensates the centrifugal force of the moon orbiting around the earth - is reexamined using new observational values for g, the earth's dimensions and the constants of the moon's motion.A first order calculation of the disturbances in the moon's orbit caused by the gravitation of the sun shows that the mass of the moon in relation to the mass of the earth must be near to 1:81 if the moons average distance from the earth's center is assumed to be 384 400 km.

  15. [Reference relationships between human and animal in Hildegard von Bingen].

    PubMed

    Riethe, Peter

    2012-01-01

    In "De animalibus", the 7th book in the "Liber simplicis medicinae", Hildegard von Bingen describes the characteristics of four-footed land animals. Some of these have a special relationship with humans in that they embody moral qualities. An explanation for this is already given in the preface, which states that human intelligence recognizes these qualities, declaring that "You are this or that sort of creature". Since the relationship that animals have with nature shares a degree of similarity with that of man's, they can be regarded as symbolic representatives for particular human traits and characteristics. The article at hand presents Hildegard von Bingen's descriptions of the monkey, the lion, the bear, the rabbit, the dog, the cat, the wolf, the lynx, and the donkey. While the monkey just mimics man's behaviour and is imperfect in both settings, the lion embodies will power. The bear on the other hand stands for unbridled sexual desire, while in the rabbit the gentleness of a sheep is united with the bounce of a deer. The lynx is regarded as hedonistic, the donkey as stupid, and the wolf as surrounded by dangerous sylphs. In Hildegard's depictions, exotic and native animal species display rather extraordinary behavioural traits, and the medieval Christian world view of the author conveys unexpected relationships between humans and animals. In addition to empirical observation and experience, Hildegard also relies on folkloristic beliefs and magical practices related to explanatory models of her time. She allows largely unknown sources into her animal lore but never strays from her ultimate goal of having it serve to instruct people. In doing so, Hildegard removed herself far from the common tradition of medieval animal portraits. PMID:23155757

  16. John von Neumann and Klaus Fuchs: an Unlikely Collaboration

    NASA Astrophysics Data System (ADS)

    Bernstein, Jeremy

    2010-03-01

    I discuss the origin of the idea of making a fusion (hydrogen) bomb and the physics involved in it, and then turn to the design proposed for one by the unlikely collaborators John von Neumann and Klaus Fuchs in a patent application they filed at Los Alamos in May 1946, which Fuchs passed on to the Russians in March 1948, and which with substantial modifications was tested on the island of Eberiru on the Eniwetok atoll in the South Pacific on May 8, 1951. This test showed that the fusion of deuterium and tritium nuclei could be ignited, but that the ignition would not propagate because the heat produced was rapidly radiated away. Meanwhile, Stanislaw Ulam and C.J. Everett had shown that Edward Teller’s Classical Super could not work, and at the end of December 1950, Ulam had conceived the idea of super compression, using the energy of a fission bomb to compress the fusion fuel to such a high density that it would be opaque to the radiation produced. Once Teller understood this, he invented a greatly improved, new method of compression using radiation, which then became the heart of the Ulam-Teller bomb design, which was tested, also in the South Pacific, on November 1, 1952. The Russians have freely acknowledged that Fuchs gave them the fission bomb, but they have insisted that no one gave them the fusion bomb, which grew out of design involving a fission bomb surrounded by alternating layers of fusion and fission fuels, and which they tested on November 22, 1955. Part of the irony of this story is that neither the American nor the Russian hydrogen-bomb programs made any use of the brilliant design that von Neumann and Fuchs had conceived as early as 1946, which could have changed the entire course of development of both programs.

  17. Dynamics of Diffusion Flames in von Karman Swirling Flows Studied

    NASA Technical Reports Server (NTRS)

    Nayagam, Vedha; Williams, Forman A.

    2002-01-01

    Von Karman swirling flow is generated by the viscous pumping action of a solid disk spinning in a quiescent fluid media. When this spinning disk is ignited in an oxidizing environment, a flat diffusion flame is established adjacent to the disk, embedded in the boundary layer (see the preceding illustration). For this geometry, the conservation equations reduce to a system of ordinary differential equations, enabling researchers to carry out detailed theoretical models to study the effects of varying strain on the dynamics of diffusion flames. Experimentally, the spinning disk burner provides an ideal configuration to precisely control the strain rates over a wide range. Our original motivation at the NASA Glenn Research Center to study these flames arose from a need to understand the flammability characteristics of solid fuels in microgravity where slow, subbuoyant flows can exist, producing very small strain rates. In a recent work (ref. 1), we showed that the flammability boundaries are wider and the minimum oxygen index (below which flames cannot be sustained) is lower for the von Karman flow configuration in comparison to a stagnation-point flow. Adding a small forced convection to the swirling flow pushes the flame into regions of higher strain and, thereby, decreases the range of flammable strain rates. Experiments using downward facing, polymethylmethacrylate (PMMA) disks spinning in air revealed that, close to the extinction boundaries, the flat diffusion flame breaks up into rotating spiral flames (refs. 2 and 3). Remarkably, the dynamics of these spiral flame edges exhibit a number of similarities to spirals observed in biological systems, such as the electric pulses in cardiac muscles and the aggregation of slime-mold amoeba. The tail of the spiral rotates rigidly while the tip executes a compound, meandering motion sometimes observed in Belousov-Zhabotinskii reactions.

  18. Die Bedeutung der Volumen- und Oberflächeneigenschaften von Biomaterialien für die Adsorption von Proteinen und nachfolgende zelluläre Reaktionen

    NASA Astrophysics Data System (ADS)

    Groth, Thomas

    2003-04-01

    Es ist schon seit längerer Zeit bekannt, dass nach Kontakt des Biomaterials mit der biologischen Umgebung bei Implantation oder extrakorporaler Wechselwirkung zunächst Proteine aus dem umgebenden Milieu adsorbiert werden, wobei die Oberflächeneigenschaften des Materials die Zusammensetzung der Proteinschicht und die Konformation der darin enthaltenden Proteine determinieren. Die nachfolgende Wechselwirkung von Zellen mit dem Material wird deshalb i.d.R. von der Adsorbatschicht vermittelt. Der Einfluss der Oberflächen auf die Zusammensetzung und Konformation der Proteine und die nachfolgende Wechselwirkung mit Zellen ist von besonderem Interesse, da einerseits eine Aussage über die Anwendbarkeit ermöglicht wird, andererseits Erkenntnisse über diese Zusammenhänge für die Entwicklung neuer Materialien mit verbesserter Biokompatibilität genutzt werden können. In der vorliegenden Habilitationsschrift wurde deshalb der Einfluss der Zusammensetzung von Polymeren bzw. von deren Oberflächeneigenschaften auf die Adsorption von Proteinen, den Aktivitätszustand der plasmatischen Gerinnung und die Adhäsion von Zellen untersucht. Dabei wurden auch Möglichkeiten zur Beeinflussung dieser Vorgänge über eine Veränderung der Volumenzusammensetzung oder durch Oberflächenmodifikationen von Biomaterialien vorgestellt. Erkenntnisse aus diesen Arbeiten konnten für die Entwicklung von Membranen für Biohybrid-Organe genutzt werden. The implantation of biomaterials or the contact of blood with extracorporal devices leads to the rapid adsorption of proteins from the surrounding biological fluids. The surface properties of materials determine the composition of the adsorption layer and the conformation of adsorbed proteins. Hence, the subsequent interaction of cells with biomaterials is dependent on the adsorption layer of proteins. The detailed knowledge on the role of surface properties in protein adsorption and cellular interactions is a useful means to learn about the biomedical applicability of materials and to develop novel materials with improved biocompatibility. The thesis describes the influence of polymer composition and surface properties on protein adsorption, the activation of blood clotting and adhesion of cells. The thesis presents options to modify the reactions of the biological system by the modification of bulk or surface composition of polymers. Results of these studies have been used to develop polymer membranes for biohybrid organs.

  19. Fluid Shear Induces Conformation Change in Human Blood Protein von Willebrand Factor in Solution

    PubMed Central

    Singh, Indrajeet; Themistou, Efrosyni; Porcar, Lionel; Neelamegham, Sriram

    2009-01-01

    Many of the physiological functions of von Willebrand Factor (VWF), including its binding interaction with blood platelets, are regulated by the magnitude of applied fluid/hydrodynamic stress. We applied two complementary strategies to study the effect of fluid forces on the solution structure of VWF. First, small-angle neutron scattering was used to measure protein conformation changes in response to laminar shear rates (G) up to 3000/s. Here, purified VWF was sheared in a quartz Couette cell and protein conformation was measured in real time over length scales from 2–140 nm. Second, changes in VWF structure up to 9600/s were quantified by measuring the binding of a fluorescent probe 1,1′-bis(anilino)-4-,4′-bis(naphtalene)-8,8′-disulfonate (bis-ANS) to hydrophobic pockets exposed in the sheared protein. Small angle neutron scattering studies, coupled with quantitative modeling, showed that VWF undergoes structural changes at G < 3000/s. These changes were most prominent at length scales <10 nm (scattering vector (q) range >0.6/nm). A mathematical model attributes these changes to the rearrangement of domain level features within the globular section of the protein. Studies with bis-ANS demonstrated marked increase in bis-ANS binding at G > 2300/s. Together, the data suggest that local rearrangements at the domain level may precede changes at larger-length scales that accompany exposure of protein hydrophobic pockets. Changes in VWF conformation reported here likely regulate protein function in response to fluid shear. PMID:19289057

  20. [The Roots of Idiographic Paleontology: Karl Alfred von Zittel's Methodology and Conception of the Fossil Record].

    PubMed

    Tamborini, Marco

    2015-12-01

    This paper examines Karl Alfred von Zittel’s practice in order to uncover the roots of so-called idiographic paleontology.The great American paleontologist Stephen Jay Gould (1941–2002) defined the discipline of idiographic paleontology as illustration and description of the morphological features of extinct species. However, this approach does not investigate macroevolutionary patterns and processes. On the contrary, the paleobiological revolution of the 1970s implemented an epistemic methodology that illustrates macrovelutionary patterns and laws by combining idiographic data with a nomothetic form of explanation. This article elucidates the features of the idiographic data as well as the acquired knowledge coupled with this approach. First of all, Heinrich G. Bronn’s (1800–1862) statistical method is analyzed. Zittel’s practice arose as a reaction against the approximate conclusions reached by Bronn’s quantitative approach. Second, the details of Zittel’s methodology are described in order to bring out its peculiarities.The microscope played a pivotal role in creating and forming Zittel’s morphological data. This analysis sheds new light on the reasons behind the so-called ideographic paleontology, thus revising Gould’s historical reconstruction, as well as on the notion of paleontological data. However, even though Zittel aimed at reaching precise and stable conclusions,his data cannot be used for elucidating evolutionary mechanisms: they are scientific in a purely descriptive sense, but completely useless for biological investigations. Finally, this paper examines how Zittel’s methodology affects the contemporary paleobiological enterprise and thereby reflects upon the notion of natural history. PMID:26507378

  1. Von Willebrand Factor permeates small vessels in CADASIL and inhibits smooth muscle gene expression

    PubMed Central

    Zhang, Xiaojie; Meng, He; Blaivas, Mila; Rushing, Elisabeth J.; Moore, Brian E.; Schwartz, Jessica; Lopes, M. Beatriz S.; Worrall, Bradford B.; Wang, Michael M.

    2011-01-01

    Background and Purpose CADASIL (cerebral autosomal dominant arteriopathy subcortical infarcts and leukoencephalopathy) is a genetic disorder hallmarked by ischemic stroke and vascular dementia. Characteristic pathological changes in the vasculature include thickening of small arteries and accumulation of heterogeneous material within the vessel wall. We tested whether endothelial von Willebrand factor (vWF) accumulates in CADASIL vessels and whether exposure of smooth muscle cells to vWF alters the expression of smooth muscle gene expression. Methods Brain sections obtained at autopsy from six North American CADASIL patients were examined using immunohistochemistry for vWF and IgG. Rat aortic smooth muscle cells (A7R5 cells) were tested for binding to infrared-tag labeled vWF. Finally, A7R5 cells were exposed to vWF, and expression of mature smooth muscle marker genes was analyzed by quantitative reverse transcriptase PCR. Results vWF is expressed in the penetrating arterial walls in all CADASIL samples. IgG, a marker of serum extravasation, was present only in a minority of arterial walls. vWF binds to smooth muscle cells in vitro, and low concentrations of vWF rapidly activate c-fos, EGR, TSP1, and c-myc while specifically inhibiting RNA encoding smooth muscle actin, calponin, and SM22. Conclusions These data demonstrate that vWF, likely produced by the endothelium, permeates the vessel wall of CADASIL brains. Exposure of smooth muscle cells to vWF results in reduction of specific RNAs required for normal vascular homeostasis. This is the first report of accumulation of a protein within CADASIL vessels that inhibits vascular gene expression and implicates a role for vWF beyond hemostasis. PMID:22639698

  2. Quantitative Techniques in Volumetric Analysis

    NASA Astrophysics Data System (ADS)

    Zimmerman, John; Jacobsen, Jerrold J.

    1996-12-01

    Quantitative Techniques in Volumetric Analysis is a visual library of techniques used in making volumetric measurements. This 40-minute VHS videotape is designed as a resource for introducing students to proper volumetric methods and procedures. The entire tape, or relevant segments of the tape, can also be used to review procedures used in subsequent experiments that rely on the traditional art of quantitative analysis laboratory practice. The techniques included are: Quantitative transfer of a solid with a weighing spoon Quantitative transfer of a solid with a finger held weighing bottle Quantitative transfer of a solid with a paper strap held bottle Quantitative transfer of a solid with a spatula Examples of common quantitative weighing errors Quantitative transfer of a solid from dish to beaker to volumetric flask Quantitative transfer of a solid from dish to volumetric flask Volumetric transfer pipet A complete acid-base titration Hand technique variations The conventional view of contemporary quantitative chemical measurement tends to focus on instrumental systems, computers, and robotics. In this view, the analyst is relegated to placing standards and samples on a tray. A robotic arm delivers a sample to the analysis center, while a computer controls the analysis conditions and records the results. In spite of this, it is rare to find an analysis process that does not rely on some aspect of more traditional quantitative analysis techniques, such as careful dilution to the mark of a volumetric flask. Figure 2. Transfer of a solid with a spatula. Clearly, errors in a classical step will affect the quality of the final analysis. Because of this, it is still important for students to master the key elements of the traditional art of quantitative chemical analysis laboratory practice. Some aspects of chemical analysis, like careful rinsing to insure quantitative transfer, are often an automated part of an instrumental process that must be understood by the analyst. This video material carefully documents several options in the process of quantitatively weighing and transferring a solid, quantitatively transferring a liquid aliquot with a pipet, and the process of quantitative volumetric titration. There are many local variants in each of these procedures. For example, some prefer to transfer solid with a weighing spoon, some with a finger held bottle, and some with a paper-strap held bottle. Students should follow the local preference, but should be aware of other acceptable options. Whatever the technique option chosen, the procedure must be done reproducibly, if analysis quality is to be optimized. Acknowledgments Quantitative Techniques in Volumetric Analysis was created with support from Project SERAPHIM and the NSF Directorate for Education and Human Resources, grant MDR-9154099.

  3. Quantitive DNA Fiber Mapping

    SciTech Connect

    Lu, Chun-Mei; Wang, Mei; Greulich-Bode, Karin M.; Weier, Jingly F.; Weier, Heinz-Ulli G.

    2008-01-28

    Several hybridization-based methods used to delineate single copy or repeated DNA sequences in larger genomic intervals take advantage of the increased resolution and sensitivity of free chromatin, i.e., chromatin released from interphase cell nuclei. Quantitative DNA fiber mapping (QDFM) differs from the majority of these methods in that it applies FISH to purified, clonal DNA molecules which have been bound with at least one end to a solid substrate. The DNA molecules are then stretched by the action of a receding meniscus at the water-air interface resulting in DNA molecules stretched homogeneously to about 2.3 kb/{micro}m. When non-isotopically, multicolor-labeled probes are hybridized to these stretched DNA fibers, their respective binding sites are visualized in the fluorescence microscope, their relative distance can be measured and converted into kilobase pairs (kb). The QDFM technique has found useful applications ranging from the detection and delineation of deletions or overlap between linked clones to the construction of high-resolution physical maps to studies of stalled DNA replication and transcription.

  4. Quantitative environmental risk analysis

    SciTech Connect

    Klovning, J.; Nilsen, E.F.

    1995-12-31

    According to regulations relating to implementation and rise of risk analysis in the petroleum activities issued by the Norwegian Petroleum Directorate, it is mandatory for an operator on the Norwegian Continental Shelf to establish acceptance criteria for environmental risk in the activities and carry out environmental risk analysis. This paper presents a {open_quotes}new{close_quotes} method for environmental risk analysis developed by the company. The objective has been to assist the company to meet rules and regulations and to assess and describe the environmental risk in a systematic manner. In the environmental risk analysis the most sensitive biological resource in the affected area is used to assess the environmental damage. The analytical method is based on the methodology for quantitative risk analysis related to loss of life. In addition it incorporates the effect of seasonal fluctuations in the environmental risk evaluations. The paper is describing the function of the main analytical sequences exemplified through an analysis of environmental risk related to exploration drilling in an environmental sensitive area on the Norwegian Continental Shelf.

  5. Quantitative Electron Nanodiffraction.

    SciTech Connect

    Spence, John

    2015-01-30

    This Final report summarizes progress under this award for the final reporting period 2002 - 2013 in our development of quantitive electron nanodiffraction to materials problems, especially devoted to atomistic processes in semiconductors and electronic oxides such as the new artificial oxide multilayers, where our microdiffraction is complemented with energy-loss spectroscopy (ELNES) and aberration-corrected STEM imaging (9). The method has also been used to map out the chemical bonds in the important GaN semiconductor (1) used for solid state lighting, and to understand the effects of stacking sequence variations and interfaces in digital oxide superlattices (8). Other projects include the development of a laser-beam Zernike phase plate for cryo-electron microscopy (5) (based on the Kapitza-Dirac effect), work on reconstruction of molecular images using the scattering from many identical molecules lying in random orientations (4), a review article on space-group determination for the International Tables on Crystallography (10), the observation of energy-loss spectra with millivolt energy resolution and sub-nanometer spatial resolution from individual point defects in an alkali halide, a review article for the Centenary of X-ray Diffration (17) and the development of a new method of electron-beam lithography (12). We briefly summarize here the work on GaN, on oxide superlattice ELNES, and on lithography by STEM.

  6. 76 FR 36166 - Culturally Significant Objects Imported for Exhibition; Determinations: “Gabriel von Max: Be...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-21

    ... and Phantasms of the Soul'' SUMMARY: Notice is hereby given of the following determinations: Pursuant... the exhibition ``Gabriel von Max: Be-Tailed Cousins and Phantasms of the Soul,'' imported from...

  7. Classification of exon 18 linked variants of VWF gene in von Willebrand disease

    PubMed Central

    Shahbazi, Shirin; Alavi, Sara; Mahdian, Reza

    2012-01-01

    Defects in von Willebrand factor, a crucial protein in haemostasis, lead to the most common inherited coagulopathy in man, von Willebrand disease. To date, over 350 mutations and 170 single nucleotide polymorphisms of VWF gene have been reported. In the present study, the distribution of two linked VWF gene variants, rs1063856 and rs1063857 have been assessed. The proportional frequency of rs1063856 (2365A/G) and rs1063857 (2385T/C) in healthy individuals were 0.70/0.30. Frequency of polymorphisms was in agreement with predicted geographical distribution. von Willebrand disease was more common in subjects with 2365A and 2385T alleles (odds ratio=1.35), although the difference was not statistically significant (p-values>0.05). The perfect correlation between these two single nucleotide polymorphisms supports their joint contribution in von Willebrand factor biology. PMID:22493754

  8. Dr. Wernher Von Braun leads a tour of the S-IC checkout area.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. Eberhard Rees, Charles Schultze, James Webb, Elmer Staats, Comptroller General of the United States, and Dr. Wernher Von Braun tour the S-IC checkout area in the Marshall Space Flight Center quality lab.

  9. von Neumann's Law: Theoretical and Microgravity Experimental Comparison for Coarsening Diffusion in Bubble Lattices

    NASA Technical Reports Server (NTRS)

    Noever, David A.

    2000-01-01

    The effects of gravity in influencing the theoretical limit for bubble lattice coarsening and aging behavior, otherwise called von Neumann's law, is examined theoretically and experimentally. Preliminary microgravity results will be discussed.

  10. Statement of Andrew von Eschenbach, M.D. - February 22, 2002

    Cancer.gov

    Statement of Andrew von Eschenbach, M.D. Director, National Cancer Institute National Institutes of Health U.S. Department of Health and Human Services Before the United States Senate Committee on Appropriations Subcommittee on Labor, Health and

  11. SUSCEPTIBILITY TO ATHEROSCLEROSIS IN AORTAS AND CORONARY ARTERIES OF SWINE WITH VON WILLEBRAND'S DISEASE

    EPA Science Inventory

    The development of coronary and aortic atherosclerosis was determined after balloon catheter injury of coronary arteries and administration of an atherogenic diet in normal pigs and pigs that were homozygous and heterozygous for von Willebrand's disease. Coronary atherosclerosis ...

  12. Variationen über Walther von Dyck und Dyck-Sprachen

    NASA Astrophysics Data System (ADS)

    Diekert, Volker; Lange, Klaus-Jörn

    Die Dyck-Sprachen sind ein Grundbegriff aus dem Bereich der formalen Sprachen. Ausgehend von der Person des Namensgebers werden ihre Geschichte und ihre Bedeutung in der theoretischen Informatik in diesem Überblick dargestellt.

  13. Alexander von Humboldt's charts of the Earth's magnetic field: an assessment based on modern models

    NASA Astrophysics Data System (ADS)

    Mandea, M.; Korte, M.; Soloviev, A.; Gvishiani, A.

    2010-11-01

    The 19th century witnessed a resurgence of interest in Earth's magnetic field. Both observational and theoretical aspects were involved, and one of the emblematic figures of this period was Alexander von Humboldt. Throughout a long life he maintained a strong interest in a broad area of subjects, however, here we are interested in his role in geomagnetism, and particularly in his pioneering contributions to charting the geomagnetic field. Alexander von Humboldt efforts in measuring and charting the Earth's magnetic field are recounted and the maps of declination, inclination and total intensity he had prepared are compared, favorably, with maps for the same epoch based on a modern model of the geomagnetic field, gufm1. This modern assessment of the accuracy of von Humboldt's geomagnetic charts illustrates the importance of his work, being also our homage to the 150th anniversary of the death of Alexander von Humboldt.

  14. Der Einsatz der Dermatoskopie in der Diagnose und Therapie von nichtmelanozytären Hautkrebsformen.

    PubMed

    Deinlein, Teresa; Richtig, Georg; Schwab, Christoph; Scarfi, Federica; Arzberger, Edith; Wolf, Ingrid; Hofmann-Wellenhof, Rainer; Zalaudek, Iris

    2016-02-01

    Die Dermatoskopie stellt heute einen integrativen Teil jeder klinischen Hautkrebsuntersuchung dar, da sie die Früherkennung von melanozytären und nichtmelanozytären Hautkrebsformen im Vergleich zur Untersuchung mit dem bloßen Auge deutlich verbessert. Neben ihrem diagnostischen Einsatz nimmt diese nichtinvasive Methode auch eine zunehmende Rolle in der Wahl und Bewertung unterschiedlicher Therapien von nichtmelanozytären Hauttumoren wie Basalzellkarzinomen, aktinischen Keratosen, Plattenepithelkarzinomen, aber auch seltenen Tumoren wie dem Merkelzellkarzinom, Angiosarkom oder dem Dermatofibrosarcoma protuberans ein. So ist die Dermatoskopie ein valides Werkzeug zur präoperativen Tumorrandbestimmung von Basalzellkarzinomen, kann aber auch zur Verlaufskontrolle nach erfolgter topischer Therapie von aktinischen Keratosen eingesetzt werden. In diesem Artikel soll ein Überblick über den Einsatz der Dermatoskopie in der Diagnose und Therapie unterschiedlicher Formen des nichtmelanozytären Hautkrebses gegeben werden. PMID:26819108

  15. Fehler begehen - Mathematik verstehen Über die Bedeutung von Fehlern für das Verstehen

    NASA Astrophysics Data System (ADS)

    Käser, Udo

    Auch wenn eine historisch oder systematisch umfassende Darstellung zur Fehlerthematik bislang nicht vorliegt, ist die Idee, einer Fehleranalyse unter der Leitfrage, welche Fehler von Schülerinnen und Schülern aufgrund welcher epistemologischen Überzeugungen begangen werden, zentralen Raum für die Betrachtung von Verstehensprozessen einzuräumen, nicht neu. So ist es geradezu ein Charakteristikum einer modernen konstruktivistischen Didaktik, die eigenen Fehler von Lernenden als ihre individuellen Lerngelegenheiten zu begreifen, die einen wichtigen Motor für den subjektiven Lernfortschritt bilden. Diese Sichtweise wurzelt aus psychologischer Perspektive in Analysen in der Tradition Piagets, der in Abkehr von einer quantitativen, psychometrischen Beschreibung kognitiver Prozesse, wie sie sich zum Beispiel in Intelligenztheorien nach Binet findet, qualitativ zu beschreiben versuchte, in welcher Weise Kinder und Jugendliche denken und urteilen. Doch auch schon in der klassischen Philosophie sind entsprechende Ansätze zu finden. Prominente Beispiele hierfür sind die Idolenlehre Bacons und die Ideenlehre Platons.

  16. In memory of Eugene (Jenő) von Gothard: a pioneering nineteenth century Hungarian astrophysicist

    NASA Astrophysics Data System (ADS)

    Vincze, Ildikő J.; Jankovics, István

    2012-07-01

    Eugene von Gothard was a Hungarian engineer/scientist, instrument-maker and astrophysicist who founded the Herény Astrophysical Observatory in 1881 and carried out pioneering work in astronomical photography and spectroscopy. In this paper we provide biographical material about von Gothard and describe his observatory, before discussing his astronomical observations and the contribution that hemade to the early development of astrophysics.

  17. Dr. von Braun with Gen. Ostrander, Dr. Rees, and Gen. Barclay

    NASA Technical Reports Server (NTRS)

    1959-01-01

    In this 1959 photo, taken at Cape Canaveral, Florida, Dr. von Braun (2nd from left) Director of the U.S. Army Ballistic Missile Agency's (ABMA) Development Operations Division, is shown conferring with Air Force Major General Donald R. Ostrander (left), on assignment at NASA as launch vehicle director; Dr. Eberhard Rees, deputy to Dr. von Braun, and Army Brigadier General John Barclay, commander of the ABMA.

  18. Dr. von Braun Presents a Hard Hat to Lady Bird Johnson

    NASA Technical Reports Server (NTRS)

    1964-01-01

    Marshall Space Flight Center Director Dr. Wernher von Braun presents Lady Bird Johnson with an inscribed hard hat during the First Lady's March 24, 1964 visit. While at the Marshall Center, Mrs. Johnson addressed Center employees, toured facilities and witnessed test firings of a Saturn I first stage and an F-1 engine. Dr. von Braun is wearing a Texas hat presented to him months earlier by Lyndon Johnson during a visit to the Johnson ranch in Texas.

  19. Quantitative Spectroscopy of Deneb

    NASA Astrophysics Data System (ADS)

    Schiller, Florian; Przybilla, N.

    We use the visually brightest A-type supergiant Deneb (A2 Ia) as benchmark for testing a spectro- scopic analysis technique developed for quantitative studies of BA-type supergiants. Our NLTE spectrum synthesis technique allows us to derive stellar parameters and elemental abundances with unprecedented accuracy. The study is based on a high-resolution and high-S/N spectrum obtained with the Echelle spectrograph FOCES on the Calar Alto 2.2 m telescope. Practically all inconsistencies reported in earlier studies are resolved. A self-consistent view of Deneb is thus obtained, allowing us to discuss its evolutionary state in detail by comparison with the most recent generation of evolution models for massive stars. The basic atmospheric parameters Teff = 8525 ± 75 K and log g = 1.10 ± 0.05 dex (cgs) and the distance imply the following fundamental parameters for Deneb: M spec = 17 ± 3 M? , L = 1.77 ± 0.29 · 105 L? and R = 192 ± 16 R? . The derived He and CNO abundances indicate mixing with nuclear processed matter. The high N/C ratio of 4.64 ± 1.39 and a N/O ratio of 0.88 ± 0.07 (mass fractions) could in principle be explained by evolutionary models with initially very rapid rotation. A mass of ˜ 22 M? is implied for the progenitor on the zero-age main se- quence, i.e. it was a late O-type star. Significant mass-loss has occurred, probably enhanced by pronounced centrifugal forces. The observational constraints favour a scenario for the evolu- tion of Deneb where the effects of rotational mixing may be amplified by an interaction with a magnetic field. Analogous analyses of such highly luminous BA-type supergiants will allow for precision studies of different galaxies in the Local Group and beyond.

  20. Quantitative Luminescence Imaging System

    SciTech Connect

    Batishko, C.R.; Stahl, K.A.; Fecht, B.A.

    1992-12-31

    The goal of the MEASUREMENT OF CHEMILUMINESCENCE project is to develop and deliver a suite of imaging radiometric instruments for measuring spatial distributions of chemiluminescence. Envisioned deliverables include instruments working at the microscopic, macroscopic, and life-sized scales. Both laboratory and field portable instruments are envisioned. The project also includes development of phantoms as enclosures for the diazoluminomelanin (DALM) chemiluminescent chemistry. A suite of either phantoms in a variety of typical poses, or phantoms that could be adjusted to a variety of poses, is envisioned. These are to include small mammals (rats), mid-sized mammals (monkeys), and human body parts. A complete human phantom that can be posed is a long-term goal of the development. Taken together, the chemistry and instrumentation provide a means for imaging rf dosimetry based on chemiluminescence induced by the heat resulting from rf energy absorption. The first delivered instrument, the Quantitative Luminescence Imaging System (QLIS), resulted in a patent, and an R&D Magazine 1991 R&D 100 award, recognizing it as one of the 100 most significant technological developments of 1991. The current status of the project is that three systems have been delivered, several related studies have been conducted, two preliminary human hand phantoms have been delivered, system upgrades have been implemented, and calibrations have been maintained. Current development includes sensitivity improvements to the microscope-based system; extension of the large-scale (potentially life-sized targets) system to field portable applications; extension of the 2-D large-scale system to 3-D measurement; imminent delivery of a more refined human hand phantom and a rat phantom; rf, thermal and imaging subsystem integration; and continued calibration and upgrade support.

  1. Workshop on quantitative dynamic stratigraphy

    SciTech Connect

    Cross, T.A.

    1988-04-01

    This document discusses the development of quantitative simulation models for the investigation of geologic systems. The selection of variables, model verification, evaluation, and future directions in quantitative dynamic stratigraphy (QDS) models are detailed. Interdisciplinary applications, integration, implementation, and transfer of QDS are also discussed. (FI)

  2. QUANTITATIVE 15N NMR SPECTROSCOPY

    EPA Science Inventory

    Line intensities in 15N NMR spectra are strongly influenced by spin-lattice and spin-spin relaxation times, relaxation mechanisms and experimental conditions. Special care has to be taken in using 15N spectra for quantitative purposes. Quantitative aspects are discussed for the 1...

  3. Helping Students Become Quantitatively Literate

    ERIC Educational Resources Information Center

    Piatek-Jimenez, Katrina; Marcinek, Tibor; Phelps, Christine M.; Dias, Ana

    2012-01-01

    In recent years, the term "quantitative literacy" has become a buzzword in the mathematics community. But what does it mean, and is it something that should be incorporated into the high school mathematics classroom? In this article, the authors will define quantitative literacy (QL), discuss how teaching for QL differs from teaching a traditional…

  4. Quantitative analysis of 'calanchi

    NASA Astrophysics Data System (ADS)

    Agnesi, Valerio; Cappadonia, Chiara; Conoscenti, Christian; Costanzo, Dario; Rotigliano, Edoardo

    2010-05-01

    Three years (2006 - 2009) of monitoring data from two calanchi sites located in the western Sicilian Appennines are analyzed and discussed: the data comes from two networks of erosion pins and a rainfall gauge station. The aim of the present research is to quantitatively analyze the effects of erosion by water and to investigate their relationships with rainfall trends and specific properties of the two calanchi fronts. Each of the sites was equipped with a grid of randomly distributed erosion pins, made of 41 nodes for the "Catalfimo" site, and 13 nodes for the "Ottosalme" site (in light of the general homogeneity of its geomorphologic conditions); the erosion pins consist in 2 cm graded iron stakes, 100 cm long, with a section having a diameter of 1.6 cm. Repeated readings at the erosion pins allowed to estimate point topographic height variations; a total number of 21 surveys have been made remotely by acquiring high resolution photographs from a fixed view point. Since the two calanchi sites are very close each other (some hundred meters), a single rainfall gauge station was installed, assuming a strict climatic homogeneity of the investigated area. Rainfall data have been processed to derive the rain erosivity index signal, detecting a total number of 27 erosive events. Despite the close distance between the two sites, because of a different geologic setting, the calanchi fronts are characterized by the outcropping of different levels of the same formation (Terravecchia fm., Middle-Late Miocene); as a consequence, both mineralogical, textural and geotechnical (index) properties, as well as the topographic and geomorphologic characteristics, change. Therefore, in order to define the "framework" in which the two erosion pin grids have been installed, 40 samples of rock have been analyzed, and a geomorphologic detailed survey has been carried out; in particular, plasticity index, liquid limit, carbonate, pH, granulometric fractions and their mineralogic properties, electrical conductivity and sodium adsorption ratio (SAR), have been characterized. The analysis of the data allows to define relationships between the response of each erosion pin and the erosive rainfall events, the micro-hydrologic of its position and lithotechnical properties of the outcropping rocks. The estimations of the mean annual erosion rate and of the erosivity index, as well as results of the terrain analysis, largely agree with available data from literature observed in similar sites affected by calanchi development. Moreover, the gained results well reflect the differences of the morphologic features and their distribution on the two calanchi fronts; of particular interest is the spatial distribution and variability of piping landforms that markedly influence the development of gullies, specially on "Catalfimo" site, where a high frequency of pipes of different typologies can be detected.

  5. Bayesian estimation of slip distribution based on von Karman autocorrelation

    NASA Astrophysics Data System (ADS)

    Hooper, A. J.; Bekaert, D. P.

    2014-12-01

    Geodetic observations from techniques such as InSAR and GNSS are routinely used to invert for earthquake fault slip distributions. However, in order to regularize the inversions, extra arbitrary assumptions about the smoothness of the slip distribution are usually included. In previous work we explored a new approach for constraining the slip distribution based on a random vector model following a von Karman autocorrelation function, which has empirical support from a stochastic analysis of seismic finite-source slip inversions. We implemented the random vector constraint in a Bayesian fashion and used a Markov chain Monte Carlo (MCMC) algorithm to derive the posterior joint probability distribution for each of the slipping patches. The von Karman function depends on two parameters: correlation length and Hurst number (related to fractal dimension). In our inversions we used the empirically derived maximum likelihood values for these two parameters, which differ in along-strike and down-dip directions, and with fault mechanism. However, the inversion results depend strongly on the chosen values for correlation length and Hurst number, and the empirically derived histograms show that there is in fact quite some variation between earthquakes with the same mechanism. In our extended approach we treat these two parameters as hyperparameters, with the prior probability distribution constrained by the empirical histograms. The values are thus also allowed to vary in our Bayesian inversion scheme. In this way, the uncertainty in the parameters that define the autocorrelation function is also included in the posterior probability distribution for the slipping patches. To ensure that our MCMC algorithm converges rapidly, we have implemented a variation to the usual MCMC approach, in which the maximum step size for each of the model parameters is initially updated regularly, until optimal values are achieved. In comparisons between our new approach and a more standard approach based on smoothing, we find the solutions with maximum posterior probability sometimes differ markedly. Even more significant, however, is the difference in the uncertainty of our results, with our new method leading to a solution with a much tighter constraint.

  6. Ansätze zur Ordnungsreduktion von nichtlinearen Oszillatormodellen zur Anwendung im Schaltungsentwurf

    NASA Astrophysics Data System (ADS)

    Reit, M.; Bremer, J.-K.; Mathis, W.; Stoop, R.

    2010-10-01

    Im Rahmen dieser Arbeit wird ein Konzept zur Ordnungsreduktion von höherdimensionalen nichtlinearen Oszillatormodellen vorgestellt. Hierbei werden zwei wesentliche Ziele verfolgt. Zum einen wird eine höherdimensionale Modellierung der Oszillatorschaltung verwendet. Hierdurch lassen sich die Einflüsse parasitärer Effekte sowie struktureller Erweiterungen auf das dynamische Verhalten des Systems berücksichtigen. Zum anderen wird durch eine anschließende Ordnungsreduktion über die Methode der Zentrumsmannigfaltigkeit eine zweidimensionale Systembeschreibung erzeugt, deren wesentliche Dynamik derjenigen des höherdimensionalen Systems entspricht. Durch diese, in der Ordnung reduzierte, nichtlineare und parameterabhängige Systembeschreibung wird die Anwendbarkeit nichtlinearer Analysemethoden ermöglicht bzw. vereinfacht. Mit der Anwendung der Andronov-Hopf-Bifurkationsanalyse auf das reduzierte System lässt sich eine Stabilitätsuntersuchung durchführen sowie die Amplitude und Frequenz aller Zustandsgrößen approximieren. Das vorgestellte Konzept wird anhand des Beispielsystems eines LC-Tank-VCOs durchgeführt. In this paper, an order reduction technique for higher-dimensional nonlinear oscillator models, based on a center manifold approach, is presented. By modeling the oscillator circuit in the higher-dimensional state space, influences of parasitic elements and of structural extensions of the oscillator architecture on the dynamical system behavior can be examined. Using the proposed order reduction technique, a generalized second order model will be derived, which includes selected design parameters of the higher order model. By using an Andronov-Hopf bifurcation analysis, the reduced system can be studied with respect to stability as well as the amplitude and frequency of the individual state variables. The concept is applied to the design of LC-tank VCOs.

  7. Ludwig von Bertalanffy's Organismic View on the Theory of Evolution

    PubMed Central

    Drack, Manfred

    2015-01-01

    Ludwig von Bertalanffy was a key figure in the advancement of theoretical biology. His early considerations already led him to recognize the necessity of considering the organism as a system, as an organization of parts and processes. He termed the resulting research program organismic biology, which he extended to all basic questions of biology and almost all areas of biology, hence also to the theory of evolution. This article begins by outlining the rather unknown (because often written in German) research of Bertalanffy in the field of theoretical biology. The basics of the organismic approach are then described. This is followed by Bertalanffy's considerations on the theory of evolution, in which he used methods from theoretical biology and then introduced his own, organismic, view on evolution, leading to the demand for finding laws of evolution. Finally, his view on the concept of homology is presented. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 77–90, 2015. © 2015 The Authors. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution published by Wiley Periodicals, Inc. PMID:25727202

  8. Minimal Coupling in Koopman-von Neumann Theory

    NASA Astrophysics Data System (ADS)

    Gozzi, E.; Mauro, D.

    2002-03-01

    Classical mechanics (CM), like quantum mechanics (QM), can have an operatorial formulation. This was pioneered by Koopman and von Neumann (KvN) in the 1930s. They basically formalized, via the introduction of a classical Hilbert space, earlier work of Liouville who had shown that the classical time evolution can take place via an operator, nowadays known as the Liouville operator. In this paper we study how to perform the coupling of a point particle to a gauge field in the KvN version of CM. So we basically implement at the classical operatorial level the analog of the minimal coupling of QM. We show that, differently than in QM, not only the momenta but also other variables have to be coupled to the gauge field. We also analyze in detail how the gauge invariance manifests itself in the Hilbert space of KvN and indicate the differences with QM. As an application of the KvN method we study the Landau problem proving that there are many more degeneracies at the classical operatorial level than at the quantum one. As a second example we go through the Aharonov-Bohm phenomenon showing that, at the quantum level, this phenomenon manifests its effects on the spectrum of the quantum Hamiltonian while at the classical level there is no effect whatsoever on the spectrum of the Liouville operator.

  9. Keeping von Willebrand Factor under Control: Alternatives for ADAMTS13.

    PubMed

    Tersteeg, Claudia; Fijnheer, Rob; Pasterkamp, Gerard; de Groot, Philip G; Vanhoorelbeke, Karen; de Maat, Steven; Maas, Coen

    2016-02-01

    Von Willebrand factor (VWF) is one of the most important proteins of the hemostatic system. Its multimeric state is essential for its natural function to guide platelets to sites of injury. ADAMTS13 is the key protease that regulates the multimeric state of VWF. Without ADAMTS13, VWF multimers can grow to pathologically large sizes. This is a risk factor for the life-threatening condition thrombotic thrombocytopenic purpura (TTP). In this condition, VWF-rich thrombi occlude the microvasculature of various tissues. Intriguingly, a complete ADAMTS13 deficiency does not cause continuous TTP, either in patients or genetically targeted mice. Instead, TTP occurs in episodes of disease, separated by extended periods of remission. This indicates that regulating factors beyond ADAMTS13 are likely involved in this pathologic cascade of events. This raises the question of what really happens when ADAMTS13 is (temporarily) unavailable. In this review, we explore the possible role of complementary mechanisms that are capable of modifying the thrombogenic potential of VWF. PMID:26595154

  10. Secreting von Willebrand factor in a G?-SNAP.

    PubMed

    Isakson, Brant E

    2014-01-16

    In this issue of Blood, Rusu et al use a state-of-the-art combination of pharmacological, genetic, and molecular techniques to dissect a mechanism for von Willebrand factor (vWF) secretion from endothelial cells mediated via Gaq/11 and Ga12 that can be triggered in basal or stimulated conditions. Indeed, although the storage of vWF in Weibel-Palade bodies (WPBs) of endothelial cells has been known for decades, the molecular mechanisms governing WPB docking with plasma membrane and vWF secretion remains undefined. One of the reasons this is still a very active area of investigation is that understanding the mechanism behind WPB docking is crucial for understanding potential pharmacological targets for pathological conditions associated with platelet aggregation/thrombi (e.g., stroke), where vWF levels directly correlate with severity of disease progress. The work by Rusu et al opens up a new area of investigation into G-protein-coupled receptors as triggers for WPB fusion at the plasma membrane and for vWF secretion. PMID:24434997

  11. Darwin the geologist: Between Lyell and von Buch.

    PubMed

    Gohau, Gabriel

    2010-02-01

    Upon returning from his voyage on the Beagle, Darwin prepared reports of his geological observations. Together, these reveal Darwin's approach to reasoning about geology. Darwin argued that successive terraces prove a very gradual elevation of the coast that lagoon islands show a reciprocal sinking of the oceanic floor. Hence, Darwin reinforced Lyell's uniformitarian, or steady state theory. Unlike lagoon islands, the movement of erratic boulders onto the plains is evidence of forces, which do not now exist. Darwin and Lyell attributed this movement to floating icebergs. However, mountain formation remained difficult for them to explain with reference to contemporary causes. Lyell discovered uplifts in Scandinavia, which resulted from epirogenesis, whereas mountain formation is an orogenesis, which involves both folding and uplift. Darwin was more impressed by uplift than by folds. However, when in Cordillera he saw strata overturned by masses of injected rock, proving successive periods of violence, Darwin took a position, which was closer to the plutonic theories of von Buch and Humboldt than it was to Lyell's uniformitarian views. PMID:20338524

  12. Allosteric activation of ADAMTS13 by von Willebrand factor.

    PubMed

    Muia, Joshua; Zhu, Jian; Gupta, Garima; Haberichter, Sandra L; Friedman, Kenneth D; Feys, Hendrik B; Deforche, Louis; Vanhoorelbeke, Karen; Westfield, Lisa A; Roth, Robyn; Tolia, Niraj Harish; Heuser, John E; Sadler, J Evan

    2014-12-30

    The metalloprotease ADAMTS13 cleaves von Willebrand factor (VWF) within endovascular platelet aggregates, and ADAMTS13 deficiency causes fatal microvascular thrombosis. The proximal metalloprotease (M), disintegrin-like (D), thrombospondin-1 (T), Cys-rich (C), and spacer (S) domains of ADAMTS13 recognize a cryptic site in VWF that is exposed by tensile force. Another seven T and two complement C1r/C1s, sea urchin epidermal growth factor, and bone morphogenetic protein (CUB) domains of uncertain function are C-terminal to the MDTCS domains. We find that the distal T8-CUB2 domains markedly inhibit substrate cleavage, and binding of VWF or monoclonal antibodies to distal ADAMTS13 domains relieves this autoinhibition. Small angle X-ray scattering data indicate that distal T-CUB domains interact with proximal MDTCS domains. Thus, ADAMTS13 is regulated by substrate-induced allosteric activation, which may optimize VWF cleavage under fluid shear stress in vivo. Distal domains of other ADAMTS proteases may have similar allosteric properties. PMID:25512528

  13. Emperor Ashoka: Did he suffer from von Recklinghausen's diseases?

    PubMed Central

    Wig, N. N.; Sharma, Sheetal

    2015-01-01

    Emperor Ashoka is widely regarded as one of the greatest rulers of India. This paper mainly deals with his medical condition as recorded in the Buddhist texts of Sri Lanka as well as in the Buddhist texts of North India and Nepal. These sources mention his skin disorder which is described as very rough and unpleasant to touch. He is also known to have episodes of loss of consciousness at various times in his life. One of the earliest representations of Ashoka, about 100 years after his death at one of the gates of Sanchi Stupa, shows Ashoka fainting when visiting the Bodhi tree and being held by his queens. In this sculpture, Emperor Ashoka is shown as a man of short height, large head and a paunchy abdomen. In this paper, it is speculated that Emperor Ashoka was probably suffering from von Recklinghausen disease (Neurofibromatosis Type 1), which could explain his skin condition, episodes of loss of consciousness (probably epilepsy) and other bodily deformities. PMID:25657467

  14. Basal secretion of von Willebrand factor from human endothelial cells.

    PubMed

    Giblin, Jonathan P; Hewlett, Lindsay J; Hannah, Matthew J

    2008-08-15

    Endothelial cells store the adhesive glycoprotein von Willebrand factor (VWF) in Weibel-Palade bodies (WPBs), distinctively shaped regulated secretory organelles that undergo exocytosis in response to secretagogue. A significant proportion of newly synthesized VWF is also secreted spontaneously from nonstimulated cells, through what is thought to be the constitutive secretory pathway. To learn more about VWF trafficking, we performed kinetic analyses of the storage and nonstimulated secretion of VWF in cultured human endothelial cells. We found that most VWF was secreted through a route that was significantly delayed compared with constitutive secretion, although this pathway was responsible for secretion of a small amount of uncleaved VWF precursor. Disruption of pH-dependent sorting processes with ammonium chloride converted the secretion kinetics of mature VWF to that of its precursor. Conversely, preventing constitutive secretion of nascent protein with brefeldin A had only a modest effect on the spontaneous release of VWF, showing that most VWF secreted by nonstimulated cells was not constitutive secretion but basal release of a post-Golgi storage organelle, presumably the WPB. These data suggest that VWF is sorted to the regulated secretory pathway in endothelial cells much more efficiently than previously reported. PMID:18344423

  15. Front End Schaltung zur Online Auswertung von EKG-Signalen

    NASA Astrophysics Data System (ADS)

    Ayari, E.; Tielert, R.

    2007-06-01

    Ein mobiles EKG-System zur Online Auswertung von EKG-Signalen wird dargestellt. Die Auswertung beruht auf ein energiesparendes Verfahren, das den Vorteil einer zulässigen Unterabtastung des Signals bietet und eine Interaktion zwischen der messenden Elektronik und dem funkgebundenen Auswertungsrechner ermöglicht. Diese Interaktion besteht darin, sowohl die Front End Schaltung im EKG-Sensor als auch den im ATmega8L eingebetteten A/D-Wandler vom Auswertungsrechner zu steuern und den Datenbedarf des Rechners dynamisch an die Erfordernisse des Analyseprogramms anzupassen. Das entwickelte EKG-System liefert erfolgreiche Charakterisierungen erfasster Elektrokardiogramme. A mobile ecg-system for an online analysis of electrocardiogram signals is presented. The analysis is based on an energy-saving procedure, which offers the advantage of an acceptable undersampling of the signal, and which allows an interaction between the measuring electronic and the radio-bound analysis-computer. In this interaction both the front-end circuit in the ecg-sensor and the A/D converter, which is embedded in the ATmega8L, are steered by the analysis computer. The data requirement of the computer is also dynamically adapted to the requirements of the analysis-program. The developed ecg-system supplies successful characterisations of measured electrocardiograms.

  16. On the Periodicity of Atmospheric von Kármán Vortex Streets

    NASA Astrophysics Data System (ADS)

    Nunalee, Christopher; Basu, Sukanta

    2013-11-01

    For over one hundred years, a similarity relationship between Strouhal number (Sr), a non-dimensional metric for vortex shedding frequency (N), and Reynolds number (Re) has been aggressively pursued in the context of von Kármán vortex streets (VKVSs). In this study, we document the Sr - Re relationship of atmospheric VKVSs (i.e., in the extremely high Re regime) in order to gain new insight into a regime of the similarity theory which has never before been investigated. Through quasi-idealized numerical simulations of realistic atmospheric VKVS events, we observe a range of Re in which mesoscale VKVSs are clearly present yet Sr remains in a steady range of 0.15 - 0.22 (irrespective of Re). This relationship resembles what has been observed for VKVSs in the much lower 102 < Re <104 regime suggesting eddy viscosity as a proxy for molecular viscosity with regards to Sr - Re similarity theory at high- Re . In addition, we find the dominant length scale dictating the Sr - Re relationship in the atmosphere to be the cross-stream mountain diameter, specifically at the height of the boundary layer thermal inversion. The authors acknowledge financial support received from the Department of Defense AFSOR grant under award number (FA9550-12-1-0449).

  17. Third International Meeting on von Hippel-Lindau disease.

    PubMed

    Zbar, B; Kaelin, W; Maher, E; Richard, S

    1999-05-01

    Five years after the identification of the von Hippel-Lindau (VHL) gene, physicians, scientists and concerned VHL family members met to review the current state of knowledge on the diagnosis and treatment of VHL and to summarize the latest information on the biochemistry of the VHL protein (pVHL). The NIH and University of Pennsylvania groups reported the detection of germ-line mutations in 100% (93 of 93) of VHL families studied. Several studies determined the frequency of VHL germ-line mutations in individuals with a single manifestation of VHL without a family history of VHL. National groups to improve the diagnosis and treatment of individuals with VHL disease have been established in Great Britain, Denmark, France, Holland, Italy, Japan, Poland, and the United States. Evidence for the existence of genes that modify the expression of VHL was presented. The VHL protein appears to have several distinct functions: (a) down-regulation of hypoxia-inducible mRNAs; (b) proper assembly of the extracellular fibronectin matrix; (c) regulation of exit from the cell cycle; and (d) regulation of expression of carbonic anhydrases 9 and 12. PMID:10232616

  18. von Kármán-Howarth relationship for helical magnetohydrodynamic flows.

    PubMed

    Politano, H; Gomez, T; Pouquet, A

    2003-08-01

    We derive an exact equation for homogeneous isotropic magnetohydrodynamic (MHD) turbulent flows with nonzero helicity; this result is of the same nature as the classical von Kármán-Howarth (VKH-HM) formulation for the kinetic energy of turbulent fluids. Helical MHD is relevant to the astrophysical flows such as in the solar corona, or the interstellar medium, and in the dynamo problem. The derivation involves the new writing of the general form of tensors for that case, for either vectors or (pseudo)axial vectors. It is shown that, for general third-order tensors, four generating functions are needed when taking into account the nonmirror invariance of helical fluids, instead of two as in the fully isotropic case. The new equation obtained, denoted by VKH-HM, links the dissipation of magnetic helicity to the third-order correlations involving combinations of the components of the velocity, the magnetic field, and the magnetic potential. Finally, in the long-time and nonresistive limit, this relationship leads to a linear scaling with separation of the third-order tensor, correlating the two normal components of the electromotive force and of the magnetic potential. PMID:14525113

  19. Dizziness and renal failure revealing the Von Hippel Lindau disease.

    PubMed

    Sekkouri, Kawtar Alaoui; Alaoui, S Rachidi; Batta, F; Belghiti, K Alaoui; Alaoui, H; El Fadil, C; Husseini, T Sqalli

    2015-01-01

    The germinal mutation of the Von Hippel Lindeau (VHL) tumor suppressor gene predisposes to the development of benign or malignant richly vascularized tumors. VHL disease is an autosomal-dominant disorder with complete penetrance at the age of 60 years. Screening for people at risk is strongly recommended, and careful monitoring allows treatment of the tumor lesions as early as possible. A 42-year-old man sought medical consult for hematuria, disabling dizziness and balance disorders lasting for two months. The neurological examination revealed the presence of a kinetic cerebellar syndrome. The cerebro-spinal magnetic resonance imaging revealed multiple hemangioblastomas, both encephalic and medullar. Abdominal computed tomography revealed a big solid mass in the left kidney and multiple intra-parenchymal cystic lesions in the right kidney and the pancreas. The diagnosis of VHL disease was strongly suspected. The operative indication of brain damage and renal mass have been submitted. The pathological study of the renal surgical specimen revealed a clear cell carcinoma. The post-operative course was uneventful and all the symptoms have disappeared. Genetic study and close follow-up are recommended for this disease. PMID:26586070

  20. Blocking von Willebrand factor for treatment of cutaneous inflammation.

    PubMed

    Hillgruber, Carina; Steingräber, Annika K; Pöppelmann, Birgit; Denis, Cécile V; Ware, Jerry; Vestweber, Dietmar; Nieswandt, Bernhard; Schneider, Stefan W; Goerge, Tobias

    2014-01-01

    Von Willebrand factor (VWF), a key player in hemostasis, is increasingly recognized as a proinflammatory protein. Here, we found a massive accumulation of VWF in skin biopsies of patients suffering from immune complex (IC)-mediated vasculitis (ICV). To clarify the impact of VWF on cutaneous inflammation, we induced experimental ICV either in mice treated with VWF-blocking antibodies or in VWF(-/-) mice. Interference with VWF led to a significant inhibition of the cutaneous inflammatory response. We confirmed the major findings in irritative contact dermatitis, a second model of cutaneous inflammation. In vivo imaging of cutaneous inflammation in the dorsal skinfold chamber revealed unaffected leukocyte rolling on anti-VWF treatment. However, we identified that reduced leukocyte recruitment is accompanied by reduced vascular permeability. Although VWF-mediated neutrophil recruitment to the peritoneum was described to require the VWF receptor on platelets (glycoprotein Ib? (GPIb?)), the VWF/GPIb? axis was dispensable for cutaneous inflammation. As assessed in tail bleeding assays, we could exclude interference of VWF blockade with hemostasis. Of particular importance, anti-VWF treatment was effective both in prophylactic and therapeutic administration. Thus, VWF represents a promising target for the treatment of cutaneous inflammation, e.g., leukocytoclastic vasculitis. PMID:23812299

  1. Empathy and identification in Von Donnersmarck's The Lives of Others.

    PubMed

    Diamond, Diana

    2008-09-01

    Florian Henckel von Donnersmarck's The Lives of Others, set in the German Democratic Republic in 1984, five years before the fall of the Berlin Wall, has been called the first accurate depiction of the psychological terror wielded by the Stasi, the East German secret police, who safeguarded the dictatorship of the proletariat. The film is about the psychological and political transformation of a Stasi officer, Wiesler, who undertakes the surveillance of a prominent playwright and his actress lover. The mechanisms through which Wiesler comes to empathize and identify with the subjects of his investigation, as he observes and listens in on the rich blend of passion, poetry, and politics that characterizes their lives, are explored in depth. Wiesler's transformation is based in part on the capacity to form implicit models of the behavior and experiences of others, based on the mirror neuron system, that Gallese and his colleagues call "embodied simulation." Underpinning the processes of empathy and identification so central to this film, embodied simulation is an unconscious and prereflexive mechanism through which the actions, emotions, and sensations we observe activate internal representations of the bodily and mental states of the other. Embodied simulation also expands our understanding of the power of the primal scene, which has long been identified as a major organizer of unconscious fantasies and conflicts throughout life, and which forms the central metaphor of the film. Embodied simulation scaffolds our aesthetic response to art, music, and literature, underlies the dynamics of spectatorship, and potentially catalyzes resistance to totalitarian mass movements. PMID:18802131

  2. Ferdinand Adolph Freiherr von Ende (1760-1816) - cornerstones for his biography. (German Title: Ferdinand Adolph Freiherr von Ende (1760-1816) - Ecksteine zu seiner Biographie)

    NASA Astrophysics Data System (ADS)

    Schwemin, Friedhelm

    2011-08-01

    The lawyer, politician and astronomer Baron von Ende is even today sometimes mentioned in astronomical literature, in most cases in connection with the discovery, by Piazzi in 1801, of the first minor planet Ceres, and especially with the associated "overture", the founding of the "Vereinigte astronomische Gesellschaft" that took place in Lilienthal near Bremen in 1800. He was one of the six founding members.

  3. News Note: Quantitative Imaging Program

    Cancer.gov

    NCI is launching a new program to qualify existing NCI designated Cancer Centers with an added attribute -- as Centers of Quantitative Imaging Excellence. This program will significantly decrease potential variability in image procedures done while a pati

  4. A monomeric von Willebrand factor fragment, Leu-504--Lys-728, inhibits von Willebrand factor interaction with glycoprotein Ib-IX [corrected

    PubMed Central

    Gralnick, H R; Williams, S; McKeown, L; Kramer, W; Krutzsch, H; Gorecki, M; Pinet, A; Garfinkel, L I

    1992-01-01

    von Willebrand factor interaction with glycoprotein Ib alpha (GPIb alpha) plays a critical role in the initial phase of platelet adhesion at high shear rates, and it may also play a role in platelet thrombus formation in partially occluded arteries. Previous studies have indicated that two peptides, Cys-474--Pro-488 (peptide 153) and Ser-692--Pro-708 (peptide 154), inhibit von Willebrand factor--GPIb alpha interaction. We have expressed a recombinant fragment of von Willebrand factor, Leu-504--Lys-728 [corrected], with a single intrachain disulfide bond linking residues Cys-509--Cys-695 and examined its ability to inhibit von Willebrand factor--GPIb alpha interactions and platelet adhesion at high shear forces. This recombinant fragment, named VCL, inhibits ristocetin-induced, botrocetin-induced, and asialo-von Willebrand factor-induced platelet aggregation and binding to platelets at an IC50 = 0.011-0.260 microM, significantly lower than the IC50 of peptide 153 or 154, IC50 = 86-700 microM. Peptides 153 and 154 did not result in any inhibition of platelet adhesion (IC50 greater than 500 microM). In contrast, VCL inhibited 50% of platelet adhesion at 0.94 microM and at 7.6 microM inhibited greater than 80% of platelet adhesion to human umbilical artery subendothelium at high shear forces. VCL inhibited the contact and spreading of platelets and also caused a marked decrease in thrombus formation. These studies indicate that VCL may be an effective antithrombotic agent in preventing arterial thrombus formation in areas of high shear force. PMID:1518808

  5. Neurocognitive profile of a young adolescent with DK phocomelia/von Voss phocomelia/von Voss Cherstvoy syndrome.

    PubMed

    Antonini, Tanya N; Van Horn Kerne, Valerie; Axelrad, Marni E; Karaviti, Lefkothea P; Schwartz, David D

    2015-07-01

    DK phocomelia/von Voss Cherstvoy syndrome is a rare condition characterized by upper limb and urogenital abnormalities and various brain anomalies. Previously reported cases have noted significant developmental delays, although no formal testing of cognitive abilities has been reported. In this paper we describe results from a comprehensive neuropsychological evaluation of a 12-year-old male with DK phocomelia syndrome. Test findings indicated mild impairment in intellectual functioning, with more significant impairment in adaptive skills and academic achievement. The neuropsychological profile converged with neurological findings, showing a distinct pattern of strengths and weaknesses that suggests functional compromise of posterior brain regions with relatively well-preserved functioning of more anterior regions. Specifically, impairments were evident in perceptual reasoning, visual perception, and visuomotor integration, whereas normal or near normal functioning was evident in memory, receptive language, social cognition, attention, and most aspects of executive functioning. To our knowledge this is the first report to describe the neurocognitive profile of an individual with DK phocomelia syndrome. PMID:25899150

  6. Precocious quantitative cognition in monkeys.

    PubMed

    Ferrigno, Stephen; Hughes, Kelly D; Cantlon, Jessica F

    2016-02-01

    Basic quantitative abilities are thought to have an innate basis in humans partly because the ability to discriminate quantities emerges early in child development. If humans and nonhuman primates share this developmentally primitive foundation of quantitative reasoning, then this ability should be present early in development across species and should emerge earlier in monkeys than in humans because monkeys mature faster than humans. We report that monkeys spontaneously make accurate quantity choices by 1 year of age in a task that human children begin to perform only at 2.5 to 3 years of age. Additionally, we report that the quantitative sensitivity of infant monkeys is equal to that of the adult animals in their group and that rates of learning do not differ between infant and adult animals. This novel evidence of precocious quantitative reasoning in infant monkeys suggests that human quantitative reasoning shares its early developing foundation with other primates. The data further suggest that early developing components of primate quantitative reasoning are constrained by maturational factors related to genetic development as opposed to learning experience alone. PMID:26187058

  7. Diagnose und Therapie einer Depression im höheren Lebensalter – Einflüsse von Patienten- und Arztmerkmalen

    PubMed Central

    von dem Knesebeck, Olaf; Bönte, Markus; Siegrist, Johannes; Marceau, Lisa; Link, Carol; McKinlay, John

    2013-01-01

    Zusammenfassung Studienergebnissee aus dem englischsprachigen Raum zeigen, dass diagnostische und therapeutische Entscheidungen von Hausärzten bei der Versorgung von depressiven Patienten systematischen Einflüssen unterliegen, und dass sowohl Merkmale des Arztes als auch des Patienten unabhängig vom Krankheitsbild Einfluss auf diese Entscheidungen haben. In der vorliegenden Arbeit werden Ergebnisse einer deutschen Studie präsentiert, in der die Einflüsse von Patienten- und Arztmerkmalen auf diagnostische und therapeutische ärztliche Entscheidungen bei einer Depression untersucht wurden. Unter Anwendung eines faktoriellen Experimentaldesigns spielten professionelle Schauspieler in Videofilmen die Rolle von Patienten, die Symptome für eine depressive Erkrankung äußern. In den Videofilmen, die alle auf einem identischen Skript basieren, wurden systematisch die Patientenmerkmale Alter (55 vs. 75 Jahre), Geschlecht und sozialer Status (Hausmeister vs. Lehrer) variiert. Die randomisierte Ärztestichprobe wurde nach dem Arztgeschlecht und professioneller Erfahrung (< 5 vs. > 15 Jahre) geschichtet. Der Videofilm wurde insgesamt 128 niedergelassenen Ärzten für Allgemeinmedizin und hausärztlich tätigen Internisten in ihrer Praxis vorgespielt. Danach wurden die Ärzte zu unterschiedlichen Aspekten von Diagnose und Therapie befragt. Es wurde erhoben, ob der Arzt dem Patienten über das gezeigte Gespräch hinausgehende Fragen stellen würde, welche Diagnosen er für wahrscheinlich hält, wie sicher er sich mit seiner Diagnose ist, welche diagnostischen Tests er anordnen würde, ob er den Patienten überweisen würde oder ob er Medikamente verordnen oder ihm Empfehlungen zur Änderung seines Lebensstils geben würde. Die Ergebnisse weisen darauf hin, dass sowohl die Diagnose als auch die Therapie einer Depression durch niedergelassene Hausärzte in Deutschland nur geringfügig durch die untersuchten Merkmale der Patienten und der behandelnden Ärzte beeinflusst wird. PMID:19274607

  8. Test of Von Baer's law of the conservation of early development.

    PubMed

    Poe, Steven

    2006-11-01

    One of the oldest and most pervasive ideas in comparative embryology is the perceived evolutionary conservation of early ontogeny relative to late ontogeny. Karl Von Baer first noted the similarity of early ontogeny across taxa, and Ernst Haeckel and Charles Darwin gave evolutionary interpretation to this phenomenon. In spite of a resurgence of interest in comparative embryology and the development of mechanistic explanations for Von Baer's law, the pattern itself has been largely untested. Here, I use statistical phylogenetic approaches to show that Von Baer's law is an unnecessarily complex explanation of the patterns of ontogenetic timing in several clades of vertebrates. Von Baer's law suggests a positive correlation between ontogenetic time and amount of evolutionary change. I compare ranked position in ontogeny to frequency of evolutionary change in rank for developmental events and find that these measures are not correlated, thus failing to support Von Baer's model. An alternative model that postulates that small changes in ontogenetic rank are evolutionarily easier than large changes is tentatively supported. PMID:17236417

  9. von Willebrand factor is dimerized by protein disulfide isomerase.

    PubMed

    Lippok, Svenja; Kolšek, Katra; Löf, Achim; Eggert, Dennis; Vanderlinden, Willem; Müller, Jochen P; König, Gesa; Obser, Tobias; Röhrs, Karoline; Schneppenheim, Sonja; Budde, Ulrich; Baldauf, Carsten; Aponte-Santamaría, Camilo; Gräter, Frauke; Schneppenheim, Reinhard; Rädler, Joachim O; Brehm, Maria A

    2016-03-01

    Multimeric von Willebrand factor (VWF) is essential for primary hemostasis. The biosynthesis of VWF high-molecular-weight multimers requires spatial separation of each step because of varying pH value requirements. VWF is dimerized in the endoplasmic reticulum by formation of disulfide bonds between the C-terminal cysteine knot (CK) domains of 2 monomers. Here, we investigated the basic question of which protein catalyzes the dimerization. We examined the putative interaction of VWF and the protein disulfide isomerase PDIA1, which has previously been used to visualize endoplasmic reticulum localization of VWF. Excitingly, we were able to visualize the PDI-VWF dimer complex by high-resolution stochastic optical reconstruction microscopy and atomic force microscopy. We proved and quantified direct binding of PDIA1 to VWF, using microscale thermophoresis and fluorescence correlation spectroscopy (dissociation constants KD = 236 ± 66 nM and KD = 282 ± 123 nM by microscale thermophoresis and fluorescence correlation spectroscopy, respectively). The similar KD (258 ± 104 nM) measured for PDI interaction with the isolated CK domain and the atomic force microscopy images strongly indicate that PDIA1 binds exclusively to the CK domain, suggesting a key role of PDIA1 in VWF dimerization. On the basis of protein-protein docking and molecular dynamics simulations, combined with fluorescence microscopy studies of VWF CK-domain mutants, we suggest the following mechanism of VWF dimerization: PDI initiates VWF dimerization by forming the first 2 disulfide bonds Cys2771-2773' and Cys2771'-2773. Subsequently, the third bond, Cys2811-2811', is formed, presumably to protect the first 2 bonds from reduction, thereby rendering dimerization irreversible. This study deepens our understanding of the mechanism of VWF dimerization and the pathophysiological consequences of its inhibition. PMID:26670633

  10. Functional anatomy of cortical areas characterized by Von Economo neurons.

    PubMed

    Cauda, Franco; Torta, Diana M E; Sacco, Katiuscia; D'Agata, Federico; Geda, Elisabetta; Duca, Sergio; Geminiani, Giuliano; Vercelli, Alessandro

    2013-01-01

    Von Economo's neurons (VENs) are large, bipolar or corkscrew-shaped neurons located in layers III and V of the frontoinsular and the anterior cingulate cortices. VENs are reported to be altered in pathologies such as frontotemporal dementia and autism, in which the individual's self control is seriously compromised. To investigate the role of VENs in the active human brain, we have explored the functional connectivity of brain areas containing VENs by analyzing resting state functional connectivity (rsFC) in 20 healthy volunteers. Our results show that cortical areas containing VENs form a network of frontoparietal functional connectivity. With the use of fuzzy clustering techniques, we find that this network comprises four sub-networks: the first network cluster resembles a "saliency detection" attentional network, which includes superior frontal cortex (Brodmann's Area, BA 10), inferior parietal lobe, anterior insula, and dorsal anterior cingulate cortex; the second cluster, part of a "sensory-motor network", comprises the superior temporal, precentral and postcentral areas; the third cluster consists of frontal ventromedial and ventrodorsal areas constituted by parts of the "anterior default mode network"; and the fourth cluster encompasses dorsal anterior cingulate cortex, dorsomedial prefrontal, and superior frontal (BA 10) areas, resembling the anterior part of the "dorsal attentional network". Thus, the network that emerges from analyzing functional connectivity among areas that are known to contain VENs is primarily involved in functions of saliency detection and self-regulation. In addition, parts of this network constitute sub-networks that partially overlap with the default mode, the sensory-motor and the dorsal attentional networks. PMID:22286950

  11. The neurofibroma in von Recklinghausen neurofibromatosis has a unicellular origin.

    PubMed

    Skuse, G R; Kosciolek, B A; Rowley, P T

    1991-09-01

    von Recklinghausen neurofibromatosis (NF1) is the most common hereditary syndrome predisposing to neoplasia. NF1 is an autosomal dominant disease caused by a single gene which maps to chromosome 17q11.2. The most common symptomatic manifestation of NF1 is the benign neurofibroma. Our previous studies of tumors in NF1, studies which detected a loss of heterozygosity for DNA markers from the NF1 region of chromosome 17 in malignant tumors, did not detect a loss in neurofibromas. We report here that a more extensive study, including the analysis of neurofibromas from 19 unrelated NF1 patients by using seven probes, failed to detect a single instance of loss of heterozygosity. This finding suggests that neurofibromas are either polyclonal or monoclonal in origin but arise by a mechanism different from that of NF1 malignancies. In order to investigate the first possibility, we analyzed neurofibromas from female NF1 patients by using an X chromosome-specific probe, from the phosphoglycerokinase (PGK) gene, which detects an RFLP. The detected alleles carry additional recognition sites for the methylation-sensitive enzyme HpaII, so that the allele derived from the active X chromosome is digested by HpaII while the one from the hypermethylated, inactive X chromosome is not. We analyzed neurofibromas from 30 unrelated females with NF1. Eight patients were heterozygous for the PGK RFLP. By this assay, neurofibromas from all eight appeared monoclonal in origin. These results suggest that benign neurofibromas in NF1 arise by a mechanism that is different from that of malignant tumors.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1715669

  12. Evaluation of von Willebrand factor in COPD patients*

    PubMed Central

    Bártholo, Thiago Prudente; da Costa, Cláudia Henrique; Rufino, Rogério

    2014-01-01

    OBJECTIVE: To compare the absolute serum von Willebrand factor (vWF) levels and relative serum vWF activity in patients with clinically stable COPD, smokers without airway obstruction, and healthy never-smokers. METHODS: The study included 57 subjects, in three groups: COPD (n = 36); smoker (n = 12); and control (n = 9). During the selection phase, all participants underwent chest X-rays, spirometry, and blood testing. Absolute serum vWF levels and relative serum vWF activity were obtained by turbidimetry and ELISA, respectively. The modified Medical Research Council scale (cut-off score = 2) was used in order to classify COPD patients as symptomatic or mildly symptomatic/asymptomatic. RESULTS: Absolute vWF levels were significantly lower in the control group than in the smoker and COPD groups: 989 ± 436 pg/mL vs. 2,220 ± 746 pg/mL (p < 0.001) and 1,865 ± 592 pg/mL (p < 0.01). Relative serum vWF activity was significantly higher in the COPD group than in the smoker group (136.7 ± 46.0% vs. 92.8 ± 34.0%; p < 0.05), as well as being significantly higher in the symptomatic COPD subgroup than in the mildly symptomatic/asymptomatic COPD subgroup (154 ± 48% vs. 119 ± 8%; p < 0.05). In all three groups, there was a negative correlation between FEV1 (% of predicted) and relative serum vWF activity (r2 = −0.13; p = 0.009). CONCLUSIONS: Our results suggest that increases in vWF levels and activity contribute to the persistence of systemic inflammation, as well as increasing cardiovascular risk, in COPD patients. PMID:25210959

  13. Quantitative high-resolution acoustic imaging of the seafloor

    NASA Astrophysics Data System (ADS)

    Holland, C. W.; Dettmer, J.; Steininger, G.; Dosso, S. E.

    2013-12-01

    Quantifying the properties of the seafloor interface and near surface (a few tens of meters) is of considerable interest to science as well as industry. Scales of interest range from the order of tens of kilometers (survey size) down to less than a centimeter. These scales can be probed using an AUV equipped with a broadband source and a short streamer. The data are processed for energy (rather than peak) reflection coefficients and scattering cross-section versus bi-static angle. In order to tackle spatial scales ranging over 8 orders of magnitude of, it is useful to divide the parameter space into deterministic and stochastic parameters. The energy reflection coefficients contain information on deterministic properties including sound speed, density and attenuation vs depth in the upper tens of meters of sediment. Vertical resolution is a function of depth, but typically of order 0.1 m near surface. The statistical properties of the smaller scales, i.e., seafloor roughness and/or volume heterogeneities are obtained from the bi-static scattering data. Physics-based models are used to relate the sediment micro-structure (the Buckingham model) and sediment fluctuations (the Von Karman spectrum) to the acoustic observables. Quantitative parameter and inter-parameter uncertainties are obtained from Bayesian methods for both deterministic and stochastic parameters.

  14. An Alternative to Von Glasersfeld's Subjectivism in Science Education: Deweyan Social Constructivism

    NASA Astrophysics Data System (ADS)

    Garrison, Jim

    An influential view of constructivism in science and mathematics educational research and practice is that of Ernst von Glasersfeld. It is a peculiarly subjectivist form of constructivism that should not be attractive to science and mathematics educators concerned with retaining some sort of realism that leaves room for objectivity. The subjectivist constructivism of von Glasersfeld also becomes entangled in untenable mind/body and subject/object dualisms. Finally, these dualisms are unnecessary for social constructivism. I will provide one example of a social constructivist alternative to social constructivism, that of the pragmatic philosopher John Dewey. In presenting Dewey's position I will appeal to Ockham's razor, that is, the admonition not to multiply entities beyond necessity, to shave off the needless mentalistic and psychic entities that lead von Glasersfeld into his subjectivism and dualism.

  15. [Viktor Borisovich von Gyubbenet--a military physician, a surgeon and a social activist].

    PubMed

    Ishutin, O S

    2015-02-01

    The current article is dedicated to a talented surgeon, an organizer of military health care, an extraordinary personality and a public figure--Doctor of Medicine, a privy councilor Victor Borisovich von Guebbenet. A talent of von Gyubbenea as a doctor-surgeon and an organizer of the surgical help on theater of war was especially brightly shown during two big military conflicts of the beginning of the XX century--the Russo-Japanese War (1904-1905) and the First World War I (1914-1918). In the first case doctor von Gyubbenet, being a surgeon of the 3rd Siberian corps successfully manage the activity of military-medical divisions and establishments of Port Arthur garrison. In the second military conflict Victor Borisovich as a doctor and an organizer headed sanitary part of armies of the Western front and successfully directed a medical support of armies of the front since 1915 and until the end of war. PMID:25920178

  16. Modelling complex geological circular data with the projected normal distribution and mixtures of von Mises distributions

    NASA Astrophysics Data System (ADS)

    Lark, R. M.; Clifford, D.; Waters, C. N.

    2014-07-01

    Circular data are commonly encountered in the earth sciences and statistical descriptions and inferences about such data are necessary in structural geology. In this paper we compare two statistical distributions appropriate for complex circular data sets: the mixture of von Mises and the projected normal distribution. We show how the number of components in a mixture of von Mises distribution may be chosen, and how one may choose between the projected normal distribution and the mixture of von Mises for a particular data set. We illustrate these methods with a few structural geological data, showing how the fitted models can complement geological interpretation and permit statistical inference. One of our data sets suggests a special case of the projected normal distribution which we discuss briefly.

  17. IntegraTUM Teilprojekt E-Mail: Rezentralisierung von E-Mail-Services

    NASA Astrophysics Data System (ADS)

    Diehn, Max; Haarer, Ado; Schreiner, Alexander; Storz, Michael

    Das Teilprojekt E-Mail hatte ursprünglich die Aufgabe einen zentralen Mailservice mit verteilter Administration der Mailadressen für die TUM aufzubauen und diesen durch Anti-Spam- und Anti-Viren-Maßnahmen zu schützen. Auf diesen Mailservice sollten sowohl die am LRZ gehosteten Maildomains als auch die vielen lokal betriebenen Mailserver - soweit von deren Betreibern gewünscht - migriert werden. Neben einigen Rückschlägen und Hindernissen kam es im Laufe des Projektes auch zu einer Änderung der Anforderungen, sodass zum Ende des Projektes statt eines reinen Mailsystems ein Doppelsystem mit "shared SMTP address space" bestehend aus einem klassischen Message-Store mit POP/IMAP-Zugriff auf Basis von Postfix + Dovecot und einem Groupware-System auf Basis von Microsoft Exchange in Produktion ging, wobei jeder Mitarbeiter und Student der TUM wählen kann, auf welchem der beiden Systeme sich seine Mailbox befindet.

  18. Display considerations for quantitative radiology.

    PubMed

    Badano, Aldo

    2007-01-01

    The early prediction of the response to treatment using quantitative imaging holds great promise for streamlining the development, assessment, approval and personalization of new therapies. However, to realize this potential, quantitative radiology needs to develop an understanding of several limitations that might hinder the application of quantitation tools and techniques. Among these limitations, the fidelity of the display device used to interpret the image data is a significant factor that affects the accuracy and precision of quantitative visual tasks, particularly those involving large, volumetric, multi-dimensional and multi-modality image sets. This paper reviews several aspects of display performance and display image quality that are likely to contribute negatively to the robustness of quantitative imaging methods. Display characteristics that will be addressed include the grayscale and color performance of different classes of display devices, the angular distribution of the emissions of liquid crystal technologies, and the temporal response for stack mode viewing. The paper will also summarize current efforts for the metrology, standardization and image quality assessment methods for display devices.: PMID:24980719

  19. "'And They Lived Happily Ever After": The Fairy Tale of Radical Constructivism and Von Glasersfeld's Ethical Disengagement

    ERIC Educational Resources Information Center

    d'Agnese, Vasco

    2015-01-01

    Is von Glasersfeld's constructivism actually radical? In this article, I respond to this question by analyzing von Glasersfeld's main works. I argue that the essential theoretical move of radical constructivism--namely the assertion that reality is the construction of a human mind that only responds to the subjective perception of "what…

  20. "'And They Lived Happily Ever After": The Fairy Tale of Radical Constructivism and Von Glasersfeld's Ethical Disengagement

    ERIC Educational Resources Information Center

    d'Agnese, Vasco

    2015-01-01

    Is von Glasersfeld's constructivism actually radical? In this article, I respond to this question by analyzing von Glasersfeld's main works. I argue that the essential theoretical move of radical constructivism--namely the assertion that reality is the construction of a human mind that only responds to the subjective perception of "what…

  1. Human von Willebrand factor gene and pseudogene: Structural analysis and differentiation by polymerase chain reaction

    SciTech Connect

    Mancuso, D.J.; Tuley, E.A.; Westfield, L.A.; Lester-Mancuso, T.L.; Sorace, J.M.; Sadler, J.E. ); Le Beau, M.M. )

    1991-01-01

    Structural analysis of the von Willebrand factor gene located on chromosome 12 is complicated by the presence of a partial unprocessed pseudogene on chromosome 22q11-13. The structures of the von Willebrand factor pseudogene and corresponding segment of the gene were determined, and methods were developed for the rapid differentiation of von Willebrand factor gene and pseudogene sequences. The pseudogene is 21-29 kilobases in length and corresponds to 12 exons (exons 23-34) of the von Willebrand factor gene. Approximately 21 kilobases of the gene and pseudogene were sequenced, including the 5{prime} boundary of the pseudogene. The 3{prime} boundary of the pseudogene lies within an 8-kb region corresponding to intron 34 of the gene. The presence of splice site and nonsense mutations suggests that the pseudogene cannot yield functional transcripts. The pseudogene has diverged {approximately}3.1{percent} in nucleotide sequence from the gene. This suggests a recent evolutionary origin {approximately}19-29 million years ago, near the time of divergence of humans and apes from monkeys. Several repetitive sequences were identified, including 4 Alu, one Line-1, and several short simple sequence repeats. Several of these simple repeats differ in length between the gene and pseudogene and provide useful markers for distinguishing these loci. Sequence differences between the gene and pseudogene were exploited to design oligonucleotide primers for use in the polymerase chain reaction to selectivity amplify sequences corresponding to exons 23-34 from either the von Willebrand factor gene or the pseudogene. This method is useful for the analysis of gene defects in patients with von Willebrand disease, without interference from homologous sequences in the pseudogene.

  2. Quantitative Proteome Mapping of Nitrotyrosines

    SciTech Connect

    Bigelow, Diana J.; Qian, Weijun

    2008-02-10

    An essential first step in the understanding disease and environmental perturbations is the early and quantitative detection of the increased levels of the inflammatory marker nitrotyrosine, as compared with its endogenous levels within the tissue or cellular proteome. Thus, methods that successfully address a proteome-wide quantitation of nitrotyrosine and related oxidative modifications can provide early biomarkers of risk and progression of disease as well as effective strategies for therapy. Multidimensional separations LC coupled with tandem mass spectrometry (LC-MS/MS) has, in recent years, significantly expanded our knowledge of human (and mammalian model system) proteomes including some nascent work in identification of post-translational modifications. In the following review, we discuss the application of LC-MS/MS for quantitation and identification of nitrotyrosine-modified proteins within the context of complex protein mixtures presented in mammalian proteomes.

  3. An Integrated Approach to von Willebrand Disease and Surgical Myocardial Revascularization

    PubMed Central

    Jiritano, Federica; Cristodoro, Lucia; Bevacqua, Egidio; Malta, Emanuele; Mastroroberto, Pasquale

    2015-01-01

    Cardiac surgery in patients with preexisting bleeding disorders can be a challenge. Cardiopulmonary bypass can lead to bleeding disorders, above all in patients with coagulopathy. We report the case of a 42-year-old woman, with type I von Willebrand disease, who underwent off-pump coronary artery bypass grafting. Beating heart surgery associated with an adequate replacement of von Willebrand factor and factor VIII levels were chosen to prevent bleeding disorders. Her postoperative course was uneventful and she was discharged home after 5 postoperative days. PMID:26693126

  4. (Never) Mind your p's and q's: Von Neumann versus Jordan on the foundations of quantum theory

    NASA Astrophysics Data System (ADS)

    Duncan, A.; Janssen, M.

    2013-03-01

    In 1927, in two papers entitled "On a new foundation [Neue Begründung] of quantum mechanics," Pascual Jordan presented his version of what came to be known as the Dirac-Jordan statistical transformation theory. Jordan and Paul Dirac arrived at essentially the same theory independently of one another at around the same time. Later in 1927, partly in response to Jordan and Dirac and avoiding the mathematical difficulties facing their approach, John von Neumann developed the modern Hilbert space formalism of quantum mechanics. We focus on Jordan and von Neumann. Central to the formalisms of both are expressions for conditional probabilities of finding some value for one quantity given the value of another. Beyond that Jordan and von Neumann had very different views about the appropriate formulation of problems in quantum mechanics. For Jordan, unable to let go of the analogy to classical mechanics, the solution of such problems required the identification of sets of canonically conjugate variables, i.e., p's and q's. For von Neumann, not constrained by the analogy to classical mechanics, it required only the identification of a maximal set of commuting operators with simultaneous eigenstates. He had no need for p's and q's. Jordan and von Neumann also stated the characteristic new rules for probabilities in quantum mechanics somewhat differently. Jordan and Dirac were the first to state those rules in full generality. Von Neumann rephrased them and, in a paper published a few months later, sought to derive them from more basic considerations. In this paper we reconstruct the central arguments of these 1927 papers by Jordan and von Neumann and of a paper on Jordan's approach by Hilbert, von Neumann, and Nordheim. We highlight those elements in these papers that bring out the gradual loosening of the ties between the new quantum formalism and classical mechanics. This paper was written as part of a joint project in the history of quantum physics of the Max Planck Institut für Wissenschaftsgeschichte and the Fritz-Haber-Institut in Berlin.

  5. Von Donuts und Zucker: Mit Neutronen biologische Makromoleküle erforschen

    NASA Astrophysics Data System (ADS)

    May, Roland P.

    2003-05-01

    Für die Erforschung von Biomolekülen bieten Neutronen einzigartige Eigenschaften. Vor allem ihre unterschiedliche Wechselwirkung mit dem natürlichen Wasserstoff und seinem schweren Isotop Deuterium ermöglicht tiefe Einblicke in Struktur, Funktion und Dynamik von Proteinen, Nukleinsäuren und Biomembranen. Bei vielen Fragestellungen zur Strukturaufklärung gibt es kaum oder keine Alternative zum Neutron. Das Institut Laue-Langevin trägt Bahnbrechendes zum Erfolg der Neutronen-Methoden in der Biologie bei.

  6. Somatostatinoma of the first jejunal loop in a patient with neurofibromatosis von Recklinghausen and bilateral pheochromocytoma.

    PubMed

    Constantinoiu, Silviu; Constantin, Adrian; Predescu, Dragos; Iosif, Cristina; Hoara, Petre; Achim, Florin; Surugiu, Paul; Bacanu, Florin; Cociu, Luminita

    2012-09-01

    Somatostatinoma is a rare neuroendocrine tumor which especially develops in the pancreas. There are few communicated cases about extra-pancreatic localization, having as a particularity the absence of somatostatin hypersecretion syndrome and frequent association with von Recklinghausen neurofibromatosis. We present the case of a 42-year old patient with Von Recklinghausen neurofibromatosis admitted in our clinic with a chronic upper digestive obstruction syndrome. The presence of a first jejunal loop somatostatinoma was an intraoperative surprising diagnosis that imposed jejunal resection and association of complementary specific treatment. Despite the therapeutic correct management, the status of the patient deteriorated very fast, confirming the aggressiveness of this neoplasia. PMID:22819908

  7. Experimental Bullard-von Karman dynamo: MHD saturated regimes

    NASA Astrophysics Data System (ADS)

    Miralles, Sophie; Plihon, Nicolas; Pinton, Jean-François

    2014-05-01

    The dynamo instability, converting kinetic energy into magnetic energy, creates the magnetic fields of many astrophysical bodies for which the flows are highly turbulent. Those turbulent fluctuations restricts the range of parameters of numerical and theoretical predictions. As laboratory experiments are closer from natural parameters, this approach is favored in this work. In the past decades, dynamo action has been observed in experiments involving laminar flows [1] or fully turbulent flows [2] in liquid sodium. Nevertheless, the saturation of the velocity field by the Lorentz force due to the dynamo magnetic field is weak in those experiment because the control parameter is always close to the threshold of the instability (which is not the case in astrophysical situations). The details of the mechanism of the back reaction of Lorentz force on the flow are not known. We present here an experimental semi-synthetic dynamo, for which a fluid turbulent induction mechanism ('omega' effect) is associated to an external amplification applying a current into a pair of coils. The flow, called von-Karman, is produced by the counter rotation of two coaxial propellers in a cylindrical tank filled with liquid gallium. The resulting flow is highly turbulent (Re > 10 ^ 5). The amplification, mimicking a turbulent 'alpha' effect, allow to observe the dynamo instability at low magnetic Reynolds number (Rm ~ 2), far below the threshold of natural homogeneous dynamo. This experiment reaches non linear regimes, for which the saturation is a MHD process, at control parameter several times the critical value. The instability grows through an on-off intermittent regime evolving into a full MHD saturated regime for which the Lorentz force is in balance with the inertial one. The power budget is strongly modified by the dynamo magnetic field and we give an insight of the estimated rate of conversion of kinetic energy into magnetic one from experimental data. Very rich regimes such as chaotic reversals of polarity are also observed and presented. Finally, a sub-critical instability has been observed under certain conditions, reminding some hypothesis formulated for geophysical situations. [1] R. Stieglitz and U. Müller, Phys. Fluids, 13, 561 (2001); A. Gailitis et al., Phys. Rev. Lett. 86, 3024 (2001) [2] Monchaux et al., Phys. Rev. Lett., 98, 044502 (2006).

  8. Zur Ganggeschwindigkeit von Uhren auf der rotierenden Erde

    NASA Astrophysics Data System (ADS)

    Richter, Gustav

    ALBERT EINSTEINS Bemerkung von 1905, daß eine am Erdäquator aufgestellte Unruh-Uhr etwas langsamer liefe als eine gleichartige, an einem der Erdpole befindliche Uhr, wird durch einen entgegenwirkenden Gravitationseffekt gerade aufgehoben, so daß alle an beliebigen Orten auf Meeresniveau befindlichen Uhren gleichschnell gehen: Die kinematische Zeitverzögerung der mit der Erddrehung bewegten Uhr erweist sich als genau entgegengesetzt gleich der Gangbeschleunigung derselben Uhr durch den Gravitationseffekt auf dem Äquatorwulst der Erde.Ferner werden das sog. Uhrenparadoxon und das Hafele-Keating-Experiment in einer etwas anderen als der meist üblichen Weise diskutiert.Translated AbstractOn the Rates of Advance of Clocks on the Rotating EarthIn 1905 ALBERT EINSTEIN came from his Special Theory of Relativity to the conclusion that a balance clock located at the earth's equator is somewhat slowed down compared with a clock resting at one of the earth's poles P (see Fig. 2 below). But interestingly, this retardation of time is fully compensated by an opposing gravitational effect which (according to the General Theory of Relativity, discovered later by EINSTEIN, 1908 - 1915) causes all (atomic) clocks even at any point A on earth's surface at normal sea-level at arbitrary latitudes to advance at the same rate as the clock at the pole: The kinematic time-dilatation of a clock A moving with the velocity v of the earth's daily revolution around its axis turns out to be precisely equal in magnitude to the acceleration of the advance of the same clock A with respect to the clock at P due to the gravitational potential-difference between A and P, resulting from the ellipsoidal figure of the rotating earth.These two variations in the clock-rates, amounting relatively to 1/2 (v/c)2, where c denotes the velocity of light in vacuum, exactly cancel each other.Furthermore the so called clock-paradox and the Hafele-Keating-Experiment are rediscussed in a somewhat different way than usual.

  9. "The captain and canon" C. W. A. von Wahl (1760-1846) (German Title: "Der Hauptmann und Kanonikus" C. W. A. von Wahl (1760-1846) )

    NASA Astrophysics Data System (ADS)

    Brosche, Peter

    Von Wahl was an active member of the group of independent scholars, who were working in the German states within Goethe's time, and who performed astrometric and geodetic observations and calculations. Here we present some cornerstones of his life; longer intervals of it took place in Allstedt south of the Harz and in Halberstadt. Small scientific assets have been preserved at the Universitäts-Sternwarte Bonn. Therein, a lecture on secular variations of the ecliptic is of singular nature.

  10. A Quantitative Infrared Spectroscopy Experiment.

    ERIC Educational Resources Information Center

    Krahling, Mark D.; Eliason, Robert

    1985-01-01

    Although infrared spectroscopy is used primarily for qualitative identifications, it is possible to use it as a quantitative tool as well. The use of a standard curve to determine percent methanol in a 2,2,2-trifluoroethanol sample is described. Background information, experimental procedures, and results obtained are provided. (JN)

  11. Quantitative Research in Written Composition.

    ERIC Educational Resources Information Center

    Gebhard, Ann O.

    Offered as an introductory guide to teachers interested in approaching written English as a "second dialect" that students must master, this review covers quantitative investigations of written language. The first section deals with developmental studies, describing how a variety of researchers have related written structure to writer maturity.…

  12. Quantitative assessment of radiation hormesis

    SciTech Connect

    Rogers, V.C.; Wilde, T.S.; Sandquist, G.M.

    1997-12-01

    A mathematical model for radiation hormesis has been developed and is graphically and quantitatively evaluated here. The model incorporates both cancer induction based on the linear dose model and cancer suppression by hormesis. The hormesis model is assessed for its ability to predict observed cancer incidence for arbitrary radiation release distribution.

  13. Towards quantitative assessment of calciphylaxis

    NASA Astrophysics Data System (ADS)

    Deserno, Thomas M.; Sárándi, István.; Jose, Abin; Haak, Daniel; Jonas, Stephan; Specht, Paula; Brandenburg, Vincent

    2014-03-01

    Calciphylaxis is a rare disease that has devastating conditions associated with high morbidity and mortality. Calciphylaxis is characterized by systemic medial calcification of the arteries yielding necrotic skin ulcerations. In this paper, we aim at supporting the installation of multi-center registries for calciphylaxis, which includes a photographic documentation of skin necrosis. However, photographs acquired in different centers under different conditions using different equipment and photographers cannot be compared quantitatively. For normalization, we use a simple color pad that is placed into the field of view, segmented from the image, and its color fields are analyzed. In total, 24 colors are printed on that scale. A least-squares approach is used to determine the affine color transform. Furthermore, the card allows scale normalization. We provide a case study for qualitative assessment. In addition, the method is evaluated quantitatively using 10 images of two sets of different captures of the same necrosis. The variability of quantitative measurements based on free hand photography is assessed regarding geometric and color distortions before and after our simple calibration procedure. Using automated image processing, the standard deviation of measurements is significantly reduced. The coefficients of variations yield 5-20% and 2-10% for geometry and color, respectively. Hence, quantitative assessment of calciphylaxis becomes practicable and will impact a better understanding of this rare but fatal disease.

  14. Quantitative Literacy for Social Justice

    ERIC Educational Resources Information Center

    Wiest, Lynda R.; Higgins, Heidi J.; Frost, Janet Hart

    2007-01-01

    In this article, we argue that many adults lack the "numeracy" needed to function in a maximally effective manner in their vocational, civic, and personal lives. We believe schools need to foster skills in quantitative literacy (QL), an inclination and ability to make reasoned decisions using general world knowledge and fundamental mathematics in…

  15. Quantitative assessment of scientific quality

    NASA Astrophysics Data System (ADS)

    Heinzl, Harald; Bloching, Philipp

    2012-09-01

    Scientific publications, authors, and journals are commonly evaluated with quantitative bibliometric measures. Frequently-used measures will be reviewed and their strengths and weaknesses will be highlighted. Reflections about conditions for a new, research paper-specific measure will be presented.

  16. Quantitative genomics of female reproduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous quantitative trait loci (QTL) for reproductive traits in domestic livestock have been described in the literature. In this chapter, the components needed for detection of reproductive trait QTL are described, including collection of phenotypes, genotypes, and the appropriate statistical ana...

  17. BOOK REVIEW: Meilensteine der Astronomie - Von Aristoteles bis Hawking

    NASA Astrophysics Data System (ADS)

    Duerbeck, H. W.; Hamel, J.

    2006-12-01

    A writer, more specific a writer on the history of astronomy, might from time to time look at the collected document folders with all the research material and reprints, and might wonder: has this been all? Especially at a time when recycling is in vogue? And, perhaps with a request or an invitation to submit something, he or she might consider re-using the material before its definitive disposal. Well, such are my feelings when I looked at Jurgen Hamel's new book Milestones of Astronomy - From Aristoteles to Hawking . A slight chance for survival of medium-sized publishers like Kosmos is to offer popular books, and a title must attract potential buyers: Aristoteles means the "old" times, and as concerns the "mad scientist" of modern times, Stephen Hawking has by now dethroned Einstein. In 1998, Hamel had published a Geschichte der Astronomie - Von den Anfangen bis zur Gegenwart (History of astronomy, from the beginnings to the present), which, of course, he could not simply copy. This time, he selected some stones from his research areas - milestones, touchstones, stumbling blocks in the long road of astronomical evolution - and put them between the covers of his new book. So let us look at these (mile)stones . The reader is informed about Aristoteles on 2 pages, but his medieval interpreter Johannes de Sacrobosco gets 8 pages! Copernicus' life and achievements are described on 9 pages, closely followed by his devotee and translator Rothmann with 8 pages; Copernicus' contemporary, Peter Apian, however, gets about 13! Bessel's and Herschel's lifes and works are described on well-deserved 13 and 15 pages, while the achievements of the two Lucasian professors, Isaac Newton and Stephen Hawking, are just outlined in a single paragraph! Thus, importance is sometimes inversely proportional to text length... But let us become serious now. Why should an active historian outline, for the hundreth time, the life of Copernicus, while there are so many interesting, and often neglected, other astronomers? Before the chapter dealing with Aristoteles and other Greek thinkers, the author presents a very good introduction to prehistoric astronomy. Subsequent chapters cover medieval times (Sacrobosco), Copernicus, instruments (Apian), calendars and their makers, telescopes and theological conflicts, women in astronomy and celestial mechanics, "amateur" astronomers (Herschel and Bessel), philosophy and science (Kant and successors). "At the limits of knowledge" is the title of the last, somewhat scanty chapter on 20th century astronomy. The only confusing text is found on p. 43: Die exzentrische Lage der Spharen wurde von Hipparch im 2. Jahrhundert v. Chr. eingefuhrt. Cum grano salis, this is correct; Hipparchos assumed an eccentric orbit for the Sun. Furthermore, die Erde steht im Mittelpunkt des Deferenten, jedoch um den Betrag der Exzentrizitat E vom Mittelpunkt des Exzenters entfernt. A figure showing a deferent circle (and attached epicycle) with center M, and a lower point E called center of world = center of Earth in the caption, tries to illustrate this. The desperate reader does not find the eccenter in the figure, and also does not appreciate why the Earth is in the center of the deferent M when the caption says it is in E. The explanation is that for a planet, having two anomalies, the epicycle does not run on a concentric circle, usually called deferent, but on an eccenter. Thus, in the figure, the circle labelled deferent is the eccenter. In Cellarius' Harmonia Macrocosmica, Table 14, a similar figure explains it all: Eccentricus deferens epicyclum - the eccenter that carries around the epicycle. Since we have switched to Latin, we should mention that on p. 158, we encountered the sentence "in dubia pro res". Perhaps we are permitted to reply "si tacuisses, philosophus mansisses". The reader is cautioned: if this book is used as a road atlas for the history of astronomy, the reader will often find very rough sketches of the progress of astronomy, but from time to time a very detailed map of a very beautiful town or village will be encountered. This well-written and inspiring book can be recommended to everyone who wants to learn about astronomical history somewhat off the beaten track.

  18. Ansätze für eine Bifurkationsanalyse von RF LC-Tank VCOs unter Berücksichtigung nichtlinearer Bauelementegleichungen

    NASA Astrophysics Data System (ADS)

    Zorn, C.; Bremer, J.-K.; Mathis, W.

    2008-05-01

    Es wird ein alternativer Ansatz zum Entwurf von vollintegrierten LC Oszillatoren mit Hilfe der Andronov-Hopf Bifurkationsanalyse unter Einbeziehung eines nichtlinearen Overall-Modells für MOS-Transistoren (EKV-Modell) vorgestellt. Das in dieser Arbeit vorgestellte Verfahren beschreibt die MOS-Kapazität des VCOs über geometrische Gundgrößen, die damit nur als Längen- und Weitenverhältnisse in die Bifurkationsanalyse eingehen. Zur Beschreibung der MOS-Kapazität wurde ein Basic-Charge-Modell, wie es in den Arbeiten von Enz und Vittoz vorgestellt wurde, in Verbindung einer expliziten analytischen Näherung des Oberflächenpotenzials verwendet. Das Verfahren ermöglicht es, als zusätzlichen Freiheitsgrad für den Designer auch die Amplitude zur Optimierung der Bauteilparameter heranzuziehen und vorab eine genauere Abschätzung der Parameter des Varaktors zu erhalten. Zusammengefasst in einer Toolbox führt die Anwendung des Verfahrens auf einen grafischen Optimierungsprozess, mit dessen Hilfe die Parameter analytisch bestimmt werden können. Die verwendete Methode erweitert den von Hajimiri und Ham vorgestellten Entwurfsprozess von LC-Tank VCOs um eine Stabilitätsanalyse, die Berücksichtigung harmonischer höherer Ordnung und die physikalisch exakte Modellierung der Varaktorkapazitäten.

  19. Untersuchung der Störwirkung von LTE auf SRD Anwendungen bei 868 MHz

    NASA Astrophysics Data System (ADS)

    Welpot, M.; Wunderlich, S.; Gaspard, I.

    2014-11-01

    Moderne Hausautomatisierungssysteme, Alarmanlagen oder auch Funk-Zugangssysteme in Haus und Automobil setzen auf frei nutzbare Frequenzen in ISM/SRD-Bändern. Die rasante Zunahme an privaten und kommerziell genutzten Applikationen im SRD-Band bei 868 MHz und der Ausbau der LTE-Mobilfunknetze im Frequenzbereich unterhalb von 1 GHz ("Digital Dividend") wirft zunehmend die Frage nach der Funkverträglichkeit dieser Systeme untereinander auf. Während die SRD-Funkmodule auf eine geringe Sendeleistung von ~ +14 dBm beschränkt sind (Ralf and Thomas, 2009), beträgt die maximale LTE-Sendeleistung im Uplink nach (ETSI-Norm, 2011) +23 dBm. Zusammen mit der Einführung von LTE im Frequenzbereich unterhalb 1 GHz als DSL-Ersatz vor allem in ländlichen Gebieten, ergibt sich damit als mögliches Störszenario, dass durch die Aussendung des LTE-Endgerätes im Bereich von ca. 850 MHz die SRD-Funkverbindungen bei 868 MHz insbesondere dann gestört werden, wenn die Antennen beider Funksysteme räumlich nahe zueinander angeordnet sind und folglich nur eine geringe zusätzliche Entkopplung der Systeme bieten. In der vorliegenden Arbeit wird das LTE-Störpotential auf SRD-Empfänger praxisnah untersucht.

  20. Perfecting the Individual: Wilhelm von Humboldt's Concept of Anthropology, "Bildung" and Mimesis

    ERIC Educational Resources Information Center

    Wulf, Christoph

    2003-01-01

    In the works of Wilhelm von Humboldt education took on a new quality, focusing firmly on the importance of the individual. "Bildung" was to become the principal task with a view to preparing the individual for the requirements of future life. In this article, the author investigates two aspects relating to the "Bildung" of the individual. First,…

  1. Einheit von Forschung und Lehre: Implications for State Funding of Universities

    ERIC Educational Resources Information Center

    Frolich, Nicoline; Coate, Kelly; Mignot-Gerard, Stephanie; Knill, Christoph

    2010-01-01

    The Humboldtian educational ideal is based on the idea of the unity of teaching and research in universities ("Einheit von Forschung und Lehre"). The role of the state, according to Humboldt, was to fund universities in such a way that their autonomy was maintained. Much has changed in the funding mechanisms of higher education systems since the…

  2. Post-selected von Neumann measurement with Hermite-Gaussian and Laguerre-Gaussian pointer states

    NASA Astrophysics Data System (ADS)

    Turek, Yusuf; Kobayashi, Hirokazu; Akutsu, Tomotada; Sun, Chang-Pu; Shikano, Yutaka

    2015-08-01

    Through the von Neumann interaction followed by post-selection, we can extract not only the eigenvalue of an observable of the measured system but also the weak value. In this post-selected von Neumann measurement, the initial pointer state of the measuring device is assumed to be a fundamental Gaussian wave function. By considering the optical implementation of the post-selected von Neumann measurement, higher-order Gaussian modes can be used. In this paper, we consider the Hermite-Gaussian (HG) and Laguerre-Gaussian (LG) modes as pointer states and calculate the average shift of the pointer states of the post-selected von Neumann measurement by assuming the system observable \\hat{A} with {\\hat{A}}2=\\hat{I} and {\\hat{A}}2=\\hat{A} for an arbitrary interaction strength, where \\hat{I} represents the identity operator. Our results show that the HG and LG pointer states for a given coupling direction have advantages and disadvantages over the fundamental Gaussian mode in improving the signal-to-noise ratio. We expect that our general treatment of the weak values will be helpful for understanding the connection between weak- and strong-measurement regimes and may be used to propose new experimental setups with higher-order Gaussian beams to investigate further the applications of weak measurement in optical systems such as the optical vortex.

  3. [Diagnostic algorithm for von Willebrand Disease (vWD) in a Mexican population].

    PubMed

    Hernández-Juárez, Jesús; Moreno-Hernández, Manuel; Majluf-Cruz, Abraham

    2015-01-01

    Distinguido editor: Sirva la presente para hacer algunas puntualizaciones en relación con el trabajo de revisión intitulado «Algoritmo diagnóstico para la enfermedad de von Willebrand (EVW) en población mexicana» (Gac Med Mex. 2015;151:399-402), ya que consideramos que tiene algunas deficiencias importantes que podrían guiar inadecuadamente al lector. PMID:26581542

  4. Citizenship Ceremony for Dr. von Braun and German-Born Scientists and Engineers

    NASA Technical Reports Server (NTRS)

    1955-01-01

    In a swearing-in ceremony held at Huntsville High School, one hundred and three German-born scientists and engineers, along with family members, took the oath of citizenship to become United States citizens. Among those taking the oath was Dr. Wernher von Braun, located in the second row, right side, third from the end.

  5. Verknüpfung von DQ-Indikatoren mit KPIs und Auswirkungen auf das Return on Investment

    NASA Astrophysics Data System (ADS)

    Block, Frank

    Häufig ist nicht klar, welche Beziehungen zwischen Datenqualitätsindikatoren (DQI, Definition folgt weiter unten) und Key Performance Indicators (KPI, s. Abschnitt 1.3 für weitere Details) eines Unternehmens oder einer Organisation bestehen. Dies ist insbesondere deshalb von Bedeutung, da die Kenntnis dieser Beziehungen maßgeblich die Ausprägung eines Datenqualitätsprojekts beeinflusst.

  6. Displacements Of Brownian Particles In Terms Of Marian Von Smoluchowski's Heuristic Model

    ERIC Educational Resources Information Center

    Klein, Hermann; Woermann, Dietrich

    2005-01-01

    Albert Einstein's theory of the Brownian motion, Marian von Smoluchowski's heuristic model, and Perrin's experimental results helped to bring the concept of molecules from a state of being a useful hypothesis in chemistry to objects existing in reality. Central to the theory of Brownian motion is the relation between mean particle displacement and…

  7. [Neurofibromatosis of the breast in a patient with Morbus von Recklinghausen].

    PubMed

    Fink, D; Schneider, C; Wight, E; Perucchini, D; Haller, U

    2000-01-01

    Neurofibromatosis is a rare autosomal dominant disorder with several subtypes. Common is the appearance of specific skin alterations. Neurofibromas occurring in the breast are very rare, and in such cases they are most common in the areolar area. A case of a 46-year-old woman with von Recklinghausen's disease of the breast is reported, and the literature will be discussed. PMID:10867496

  8. A Von Karman integral approach to a two phase boundary layer problem

    NASA Technical Reports Server (NTRS)

    Henry, R.; Pasamehmetoglu, P.; Eno, B.; Anderson, L.

    1987-01-01

    A Von Karman integral approximation of a two phase boundary layer is developed for bodies of arbitrary shape. The flow field considered is that of the injection of water through a porous airfoil. A solution for the special case of a flat plate is presented. The equations for the airfoil solution are developed and possible effects on airflow separation are discussed.

  9. Finite dimensional attractors for von Karman systems with nonlinear dissipation and noncompact nonlinearity

    SciTech Connect

    Lasiecka, I.

    1994-12-31

    We consider the model of a nonlinear plate with nonlinear damping described by the von Karman system. Here, the variable w represent respectively, a vertical displacement and the plane displacement of a thin plate occupying a two dimensional domain {Omega} with a sufficiently smooth boundary {Tau}.

  10. Numerical solutions of the Von Karman equations for a thin plate

    SciTech Connect

    Da Silva, P.P.; Krauth, W.

    1997-04-01

    In this paper, we present an algorithm for the solution of the von Karman equations of elasticity theory and related problems. Our method of successive reconditioning is able to avoid convergence problems at any ratio of the nonlinear stretching and the pure bending energies. We illustrate the power of the method by numerical calculations of pinched or compressed plates subject to fixed boundaries.

  11. Identifikationsverfahren zur Analyse von EEG-Signalen bei Epilepsie mit Reaktions-Diffusions Netzwerken

    NASA Astrophysics Data System (ADS)

    Gollas, F.; Tetzlaff, R.

    2007-06-01

    Partielle Differentialgleichungen des Reaktions-Diffusions-Typs beschreiben Phänomene wie Musterbildung, nichtlineare Wellenausbreitung und deterministisches Chaos und werden oft zur Untersuchung komplexer Vorgänge auf den Gebieten der Biologie, Chemie und Physik herangezogen. Zellulare Nichtlineare Netzwerke (CNN) sind eine räumliche Anordnung vergleichsweise einfacher dynamischer Systeme, die eine lokale Kopplung untereinander aufweisen. Durch eine Diskretisierung der Ortsvariablen können Reaktions-Diffusions-Gleichungen häufig auf CNN mit nichtlinearen Gewichtsfunktionen abgebildet werden. Die resultierenden Reaktions-Diffusions-CNN (RD-CNN) weisen dann in ihrer Dynamik näherungsweise gleiches Verhalten wie die zugrunde gelegten Reaktions-Diffusions-Systeme auf. Werden RD-CNN zur Identifikation neuronaler Strukturen anhand von EEG-Signalen herangezogen, so besteht die Möglichkeit festzustellen, ob das gefundene Netzwerk lokale Aktivität aufweist. Die von Chua eingeführte Theorie der lokalen Aktivität Chua (1998); Dogaru und Chua (1998) liefert eine notwendige Bedingung für das Auftreten von emergentem Verhalten in zellularen Netzwerken. Änderungen in den Parametern bestimmter RD-CNN könnten auf bevorstehende epileptische Anfälle hinweisen. In diesem Beitrag steht die Identifikation neuronaler Strukturen anhand von EEG-Signalen durch Reaktions-Diffusions-Netzwerke im Vordergrund der dargestellten Untersuchungen. In der Ergebnisdiskussion wird insbesondere auch die Frage nach einer geeigneten Netzwerkstruktur mit minimaler Komplexität behandelt.

  12. Einstellung und Wissen von Lehramtsstudierenden zur Evolution - ein Vergleich zwischen Deutschland und der Türkei

    NASA Astrophysics Data System (ADS)

    Graf, Dittmar; Soran, Haluk

    Es wird eine Untersuchung vorgestellt, in der Wissen und Überzeugungen von Lehramtsstudierenden aller Fächer zum Thema Evolution an zwei Universitäten in Deutschland und der Türkei erhoben worden sind. Die Befragung wurde in Dortmund und in Ankara durchgeführt. Es stellte sich heraus, dass ausgeprägte Defizite im Verständnis der Evolutionsmechanismen herrschen. Viele Studierende, insbesondere aus der Türkei, sind nicht von der Faktizität der Evolution überzeugt. Dies gilt sowohl für Studierende mit Fach Biologie als auch für Studierende mit anderen Fächern. Näher untersucht worden sind die Faktoren, die die Überzeugungen zur Evolution beeinflussen können, was ja in Anbetracht der hohen Ablehnungsrate der Evolution von besonderem Interesse ist. Das Vertrauen in die Wissenschaft spielt hierbei eine besondere Rolle: Wer der Wissenschaft vertraut, ist auch eher von der Evolution überzeugt, als diejenigen, die skeptisch gegenüber der Wissenschaft sind.

  13. Dr. Wernher Von Braun greeting dignitaries at the Redstone Arsenal airfield.

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Dr. George E. Mueller, center, associate administrator for manned space flight, is flanked by Dr. Wernher Von Braun, left, and Dr. Eberhard Rees at the Redstone Arsenal airstrip. the associate adminstrator was making his annual staff visit to the Marshall Space Flight Center.

  14. Dr. Wernher Von Braun on Tour With U.S. congressman Armistead Seldon

    NASA Technical Reports Server (NTRS)

    1999-01-01

    U.S. representative Armistead Seldon (D.-Al) tries on an astronaut maneuvering unit mockup during a tour of the Saturn I workshop at the Marshall Space Flight center. Explaining the unit and the workshop to Representative Seldon is Dr. Wernher Von Braun, director of the Marshall Center.

  15. Asymptotic Power Properties of the Cramer-von Mises Test Under Contiguous Alternatives

    ERIC Educational Resources Information Center

    Neuhaus, Georg

    1976-01-01

    The asymptotic power of the Cramer-von Mises test when parameters are estimated from the data is studied under certain local (contiguous) alternatives. Notion of (asymptotic) direction and distance from the null hypothesis of alternatives is introduced, and it is shown that there exist directions with maximum, minimum, and arbitrary intermediate…

  16. [Correspondence between Winkler and Von Monakow. 2. Developments in psychiatry and neurology (1900-1930)].

    PubMed

    Koehler, P J; Jagella, C

    2001-12-22

    In this second article Winkler's and Von Monakow's views on the evolution of psychiatry and neurology (1900-1930) are described. They discussed a number of scientific subjects in their correspondence, such as the localisation of functions in the central nervous system and in particular Von Monakow's concept of 'diaschisis'. This concept explained the phenomenon that symptoms during the acute phase of central nervous system disorders are more extensive and of a different nature than those during the chronic phase. The controversy between the neuron theory and the reticular theory was also discussed in the correspondence. One of the reasons for the correspondence and meetings was the plan to compile an atlas of the brain although due to the outbreak of World War I this did not come to fruition. Finally there was an extensive correspondence concerning the psychoanalytic movement within the psychiatry, of which Winkler and Von Monakow, as biologically orientated neuropsychiatrists, were highly critical. German language neuropsychiatry has had a considerable influence in the Netherlands and this is in part due to the relationship Winkler had with German neuropsychiatrists and Von Monakow in particular. PMID:11789153

  17. Assoziativspeicher und eine erste Skizze von Konrad Zuse aus dem Jahre 1943

    NASA Astrophysics Data System (ADS)

    Waldschmidt, Klaus

    In dem Beitrag wird eine Handskizze von Konrad Zuse aus dem Jahre 1943 eines assoziativen Speichers in Relaistechnik diskutiert. Die Diskussion ist eingebettet in die Grundlagen des assoziativen Speicherproblems. Zum Schluss des Beitrages werden einige Vorschläge zu MOSRealisierung der Zuse-Schaltung unterbreitet.

  18. Dr. von Braun Relaxes After the Successful Launch of Apollo 11

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Dr. Wernher von Braun, first director of the Marshall Space Flight Center, relaxes following the successful launch of the Saturn V carrying Apollo 11 to the moon. The towering 363-foot Saturn V was a multi-stage, multi-engine launch vehicle standing taller than the Statue of Liberty. Altogether, the Saturn V engines produced as much power as 85 Hoover Dams.

  19. Von Steuben and the German Contribution to the American Revolution: A Selective Bibliography.

    ERIC Educational Resources Information Center

    Krewson, Margrit B.

    This Library of Congress selected bibliography highlights the efforts of Baron Friedrich Wilhelm von Steuben, other German and German-American military leaders, and the Hessian auxiliary military forces in assisting the American colonies during the Revolutionary War. The booklet is divided into five parts. Part 1 provides historical information…

  20. Beyond victimhood. The struggle of Munich anatomist Titus von Lanz during National Socialism.

    PubMed

    Schütz, Mathias; Waschke, Jens; Marckmann, Georg; Steger, Florian

    2015-09-01

    The article analyzes the life and career of the anatomist Titus von Lanz (1897-1967) of Munich focusing on the period of National Socialism (NS). Von Lanz lost his position as an associate professor at the Anatomical Institute of Munich University because of his marriage to a "half-Jewish" woman in 1938. In contrast to most of his colleagues affected by National Socialist measures, von Lanz had opportunities to save his career and made extensive use of them. His story is that of a complicated struggle for the continuation of his work, involving a wide range of supporters from prestigious physicians to high-ranking National Socialist officials as well as the alienation of his colleagues at the Munich department of anatomy. The article tries to clarify these developments through the presentation of his social background, his supporters, his enemies, the research he conducted during NS and von Lanz' own remembrance of these developments from the post-war period. It aims at laying out a critical appreciation of his motives and actions, thereby contributing to the understanding of individual behavior of anatomists under NS. PMID:26208340

  1. Space: The Long-Range Future: An Interview with Jesco von Puttkamer.

    ERIC Educational Resources Information Center

    Lawler, Andrew

    1985-01-01

    Jesco von Puttkamer manages long-range planning in NASA's Office of Space Flight. He believes that space offers the opportunity to ease global tensions, help the developing world, and create a new global culture off the planet. (Author/RM)

  2. Displacements Of Brownian Particles In Terms Of Marian Von Smoluchowski's Heuristic Model

    ERIC Educational Resources Information Center

    Klein, Hermann; Woermann, Dietrich

    2005-01-01

    Albert Einstein's theory of the Brownian motion, Marian von Smoluchowski's heuristic model, and Perrin's experimental results helped to bring the concept of molecules from a state of being a useful hypothesis in chemistry to objects existing in reality. Central to the theory of Brownian motion is the relation between mean particle displacement and…

  3. Wilhelm von Humboldt and the "Orient": On Edward W. Said's Remarks on Humboldt's Orientalist Studies

    ERIC Educational Resources Information Center

    Messling, Markus

    2008-01-01

    From an epistemological perspective, Wilhelm von Humboldt's studies on the Oriental and East Asian languages and writing systems (Egyptian hieroglyphs, Sanskrit, Chinese, Polynesian) raise the question of his position in the Orientalist discourse of his time. Said [Said, E.W., 1978. "Orientalism. Western Conceptions of the Orient, fourth ed."…

  4. Wilhelm von Humboldt and the "Orient": On Edward W. Said's Remarks on Humboldt's Orientalist Studies

    ERIC Educational Resources Information Center

    Messling, Markus

    2008-01-01

    From an epistemological perspective, Wilhelm von Humboldt's studies on the Oriental and East Asian languages and writing systems (Egyptian hieroglyphs, Sanskrit, Chinese, Polynesian) raise the question of his position in the Orientalist discourse of his time. Said [Said, E.W., 1978. "Orientalism. Western Conceptions of the Orient, fourth ed."…

  5. On the Relation of Von Mises Equation with Acoustic Black Holes

    NASA Astrophysics Data System (ADS)

    Cherubini, Christian; Filippi, Simonetta

    2015-01-01

    In this article a discussion of Analogue Gravity is presented in relation with its recently discovered relation, valid at any perturbative order, with the nonlinear Von Mises wave equation of fluid dynamics. A discussion of the role of the acoustic metric at nonlinear level is presented.

  6. The natural history of occult or angiodysplastic gastrointestinal bleeding in von Willebrand disease.

    PubMed

    Makris, M; Federici, A B; Mannucci, P M; Bolton-Maggs, P H B; Yee, T T; Abshire, T; Berntorp, E

    2015-05-01

    Recurrent gastrointestinal bleeding is one of the most challenging complications encountered in the management of patients with von Willebrand disease (VWD). The commonest cause is angiodysplasia, but often no cause is identified due to the difficulty in making the diagnosis. The optimal treatment to prevent recurrences remains unknown. We performed a retrospective study of VWD patients with occult or angiodysplastic bleeding within the setting of the von Willebrand Disease Prophylaxis Network (VWD PN) to describe diagnostic and treatment strategies. Centres participating in the VWD PN recruited subjects under their care with a history of congenital VWD and gastrointestinal (GI) bleeding due to angiodysplasia, or cases in which the cause was not identified despite investigation. Patients with acquired von Willebrand syndrome or those for whom the GI bleeding was due to another cause were excluded. Forty-eight patients from 18 centres in 10 countries were recruited. Seven individuals had a family history of GI bleeding and all VWD types except 2N were represented. Angiodysplasia was confirmed in 38%, with video capsule endoscopy and GI tract endoscopies being the most common methods of making the diagnosis. Recurrent GI bleeding in VWD is associated with significant morbidity and required hospital admission on up to 30 occasions. Patients were treated with multiple pharmacological agents with prophylactic von Willebrand factor concentrate being the most efficient in preventing recurrence of the GI bleeding. The diagnosis and treatment of recurrent GI bleeding in congenital VWD remains challenging and is associated with significant morbidity. Prophylactic treatment with von Willebrand factor concentrate was the most effective method of preventing recurrent bleeding but its efficacy remains to be confirmed in a prospective study. PMID:25381842

  7. Quantitative phase imaging of arthropods

    NASA Astrophysics Data System (ADS)

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-11-01

    Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy.

  8. A quantitative ELISA for dystrophin.

    PubMed

    Morris, G E; Ellis, J M; Nguyen, T M

    1993-05-01

    A novel approach to the quantitation of the muscular dystrophy protein, dystrophin, in muscle extracts is described. The two-site ELISA uses two monoclonal antibodies against dystrophin epitopes which lie close together in the rod domain of the dystrophin molecule in order to minimize the effects of dystrophin degradation. Dystrophin is assayed in its native form by extracting with non-ionic detergents and avoiding the use of SDS. PMID:8486926

  9. Contribution of the collagen binding activity (VWF:CB) in the range of tests for the diagnosis and classification of von Willebrand disease.

    PubMed

    Ferhat-Hamida, Meriem Yasmine; Boukerb, Houda; Hariti, Ghania

    2015-01-01

    Von willebrand disease (VWD) is a common inherited bleeding disorder. The diagnosis may need a large panel of tests that differ in term of sensibility and specificity, and because of the effect of multifactorial modifiers (genetic or environmental); there is difficulty in defining diagnostic limits. We performed a panel of tests on 19 patients suffering from recurrent bleeding, to diagnose and classify VWD subtypes, by introducing the von Willebrand factor (VWF) collagen binding test (VWF:CB), then comparing the results with the activity of VWF risticetin cofactor (VWF:RCo) and multimer pattern. We considered 30% limit rate of VWF, as described by many authors, to make the diagnosis of VWD. The diagnosis of type 1 of VWD has been confirmed in 7patients, subtype 2A in 2 patients, subtype 2M in 2 patients and type 3 in 2 patients. We also defined a new group of 6 patients named "uncertain type 1" that didn't fill into the type 1 diagnostic criterion. The comparison between VWF:CB and VWF:RCo showed good correlation for all types of VWD except for type 2 while comparison between VWF:CB and multimer pattern showed good concordance for all types of VWD diagnosed. In conclusion, VWF:CB can be a good alternative to VWF:RCo for the diagnosis of quantitative deficiencies of VWF. It can also replace the multimer pattern study. However, the introduction of VWF:CB didn't help in the diagnosis of the "uncertain type 1" group of patients and cannot be a replacement for qualitative defect. PMID:26411913

  10. Quantitative Relaxometry of the Brain

    PubMed Central

    Deoni, Sean C.L.

    2011-01-01

    The exquisite soft tissue contrast provided by magnetic resonance imaging arises principally from differences in the intrinsic relaxation properties, T1 and T2. Though the intricate relationships that link tissue microstructure and the longitudinal and transverse relaxation times remain to be firmly established, quantitative measurement of these parameters, also referred to as quantitative relaxometry, can be informative of disease-related tissue change, developmental plasticity, and other biological processes. Further, relaxometry studies potentially offer a more detailed characterization of tissue, compared with conventional qualitative or weighted imaging approaches. The purpose of this review is to briefly review the biophysical basis of relaxation, focusing specifically on the T1, T2 and T2* relaxation times, and to detail some of the more widely used and clinically feasible techniques for their in vivo measurement. We will focus on neuroimaging applications, though the methods described are equally well suited to cardiac, abdominal and musculoskeletal imaging. Potential sources of error, and methods for their correction, are also touched on. Finally, the combination of relaxation time data with other complementary quantitative imaging data, including diffusion tensor imaging, is discussed, with the aim of more thoroughly characterizing brain tissue. PMID:21613875

  11. Herausforderungen und Best Practices bei der Speicherung von multi-valued Attributen in LDAP-basierten Verzeichnisdiensten

    NASA Astrophysics Data System (ADS)

    Hommel, Wolfgang; Pluta, Daniel

    LDAP-basierte Verzeichnisdienste unterscheiden sich von relationalen Datenbankmanagementsystemen unter anderem stark bezüglich der Datenmodellierung. Dieser Artikel vertieft eingangs die Herausforderungen bei der LDAP-spezifischen Abbildung von Relationen zwischen mehreren multivalued Attributen. Die Diskussion erfolgt vor dem Hintergrund, dass einerseits Verzeichnisdienste generell nur bedingt zur Speicherung von Relationen geeignet sind und dass andererseits multi-valued Attribute ein mächtiges LDAP-Instrument sind, zu dem es in relationalen Datenbanksystemen keine direkte Entsprechung gibt. Anschließend werden Lösungskonzepte vorgestellt und mögliche Weiterentwicklungen des IntegraTUM-LDAP-Schemas zu deren Umsetzung skizziert, eine exemplarische Implementierung präsentiert und die Ergebnisse der bisherigen Entwicklung des IntegraTUM-Schemas gegenübergestellt.

  12. Aspects of hydrodynamic shear regulating shear-induced platelet activation and self-association of von Willebrand factor in suspension.

    PubMed

    Shankaran, Harish; Alexandridis, Paschalis; Neelamegham, Sriram

    2003-04-01

    The binding of plasma von Willebrand factor (VWF) to platelet receptor GpIb under high hydrodynamic shear leads to platelet activation and subsequent shear-induced platelet aggregation (SIPA). We quantitatively examined the aspects of fluid flow that regulate platelet activation by subjecting human blood and isolated platelets to well-defined shear conditions in a cone-plate viscometer. We made the following observations. First, Annexin V binding to phosphatidyl serine expressed on activated cells was detectable within 10 seconds of shear application. Second, fluid shear stress rather than shear rate controls platelet activation, and a threshold shear stress of approximately 80 dyn/cm(2) is necessary to induce significant activation. Under these conditions, individual domains of soluble VWF and platelet GpIb are subjected to similar magnitudes of fluid forces on the order of 0.1 pN, whereas GpIb with bound VWF is subjected to 1 pN. Third, cell-cell collisions and time-varying stresses are not essential for platelet activation. Fourth, the mechanism of platelet activation can be resolved in 2 steps based on the contribution of VWF and fluid forces. Fluid shear and VWF are required during the first step, when GpIb-VWF binding likely occurs. Subsequently, high shear forces alone in the absence of VWF in suspension can induce platelet activation. In other experiments, purified VWF was subjected to shear in the viscometer, and VWF morphology was assessed using light scattering. These studies demonstrate, for the first time, the ability of hydrodynamic forces to induce VWF aggregation in suspension. This VWF self-association may be an additional feature involved in controlling cell adhesion rates in circulation. PMID:12456504

  13. A molten globule intermediate of the Von Willebrand Factor A1 domain firmly tethers platelets under shear flow

    PubMed Central

    Tischer, Alexander; Madde, Pranathi; Blancas-Mejia, Luis. M.; Auton, Matthew

    2014-01-01

    Clinical mutations in patients diagnosed with Type 2A von Willebrand disease (vWD) have been identified that break the single disulfide bond linking N- and C-termini in the vWF A1 domain. We have modeled the effect of these mutations on the disulfide-bonded structure of A1 by reducing and carboxy-amidating these cysteines. Solution biophysical studies show that loss of this disulfide bond induces a molten globule conformational state lacking global tertiary structure but retaining residual secondary structure. The conformational dependence of platelet adhesion to these native and molten globule states of A1 is quantitatively compared using real-time high-speed video microscopy analysis of platelet translocation dynamics under shear flow in a parallel plate micro-fluidic flow chamber. While normal platelets translocating on surface-captured native A1 domain retain the catch-bond character of pause times that increase as a function of shear rate at low shear and decrease as a function of shear rate at high shear, platelets that interact with A1 lacking the disulfide bond remain stably attached and do not translocate. Based on these findings, we propose that the shear stress-sensitive regulation of the A1-GPIb interaction is due to folding the tertiary structure of this domain. Removal of the tertiary structure by disrupting the disulfide bond destroys this regulatory mechanism resulting in high-strength interactions between platelets and vWF A1 that are dependent only on residual secondary structure elements present in the molten globule conformation. PMID:24265179

  14. Influence of the fluid density on the statistics of power fluctuations in von Kármán swirling flows

    NASA Astrophysics Data System (ADS)

    Opazo, A.; Sáez, A.; Bustamante, G.; Labbé, R.

    2016-02-01

    Here, we report experimental results on the fluctuations of injected power in confined turbulence. Specifically, we have studied a von Kármán swirling flow with constant external torque applied to the stirrers. Two experiments were performed at nearly equal Reynolds numbers, in geometrically similar experimental setups. Air was utilized in one of them and water in the other. With air, it was found that the probability density function of power fluctuations is strongly asymmetric, while with water, it is nearly Gaussian. This suggests that the outcome of a big change of the fluid density in the flow-stirrer interaction is not simply a change in the amplitude of stirrers' response. In the case of water, with a density roughly 830 times greater than air density, the coupling between the flow and the stirrers is stronger, so that they follow more closely the fluctuations of the average rotation of the nearby flow. When the fluid is air, the coupling is much weaker. The result is not just a smaller response of the stirrers to the torque exerted by the flow; the PDF of the injected power becomes strongly asymmetric and its spectrum acquires a broad region that scales as f-2. Thus, the asymmetry of the probability density functions of torque or angular speed could be related to the inability of the stirrers to respond to flow stresses. This happens, for instance, when the torque exerted by the flow is weak, due to small fluid density, or when the stirrers' moment of inertia is large. Moreover, a correlation analysis reveals that the features of the energy transfer dynamics with water are qualitatively and quantitatively different to what is observed with air as working fluid.

  15. Die nuklearen Anlagen von Hanford (1943-1987) Eine Fallstudie über die Schnittstellen von Physik, Biologie und die US-amerikanische Gesellschaft zur Zeit des Kalten Krieges

    NASA Astrophysics Data System (ADS)

    Macuglia, Daniele

    Die Geschichte des Kalten Krieges eröffnet viele Möglichkeiten, sich näher mit den Schnittstellen von Physik und Biologie während des 20. Jahrhunderts zu befassen. Nicht nur das Unglück in Tschernobyl aus dem Jahr 1986, auch das Beispiel der nuklearen Anlagen in Hanford in den Vereinigten Staaten zeigt die biologischen Folgen von nuklearer Physik.

  16. Versuche zur Gewinnung von katalytischen Antikörpern zur Hydrolyse von Arylcarbamaten und Arylharnstoffen. (English Title: Attempts to produce catalytic antibodies for hydrolysis of arylcarbamates and arylureas)

    NASA Astrophysics Data System (ADS)

    Werner, Deljana

    2002-05-01

    Im Rahmen dieser Arbeit gelang es, katalytische Antikörper zur Hydrolyse von Benzylphenylcarbamaten sowie zahlreiche monoklonale Antikörper gegen Haptene herzustellen. Es wurden verschiedene Hapten-Protein-Konjugate unter Verwendung unterschiedlicher Kopplungsmethoden hergestellt und charakterisiert. Zur Generierung der hydrolytisch aktiven Antikörper wurden Inzuchtmäuse mit KLH-Konjugaten von 4 Übergangszustandsanaloga (ÜZA) immunisiert. Mit Hilfe der Hybridomtechnik wurden verschiedene monoklonale Antikörper gegen diese ÜZA gewonnen. Dabei wurden sowohl verschiedene Immunisierungsschemata als auch verschiedene Inzuchtmausstämme und Fusionstechniken verwendet. Insgesamt wurden 32 monoklonale Antikörper gegen die verwendeten ÜZA selektiert. Diese Antikörper wurden in groen Mengen hergestellt und gereinigt. Zum Nachweis der Antikörper-vermittelten Katalyse wurden verschiedene Methoden entwickelt und eingesetzt, darunter immunologische Nachweismethoden mit Anti-Substrat- und Anti-Produkt-Antikörpern und eine photometrische Methode mit Dimethylaminozimtaldehyd. Der Nachweis der hydrolytischen Aktivität gelang mit Hilfe eines Enzymsensors, basierend auf immobilisierter Tyrosinase. Die Antikörper N1-BC1-D11, N1-FA7-C4, N1-FA7-D12 und R3-LG2-F9 hydrolysierten die Benzylphenylcarbamate POCc18, POCc19 und Substanz 27. Der Nachweis der hydrolytischen Aktivität dieser Antikörper gelang auch mit Hilfe der HPLC. Der katalytische Antikörper N1-BC1-D11 wurde kinetisch und thermodynamisch untersucht. Es wurde eine Michaelis-Menten-Kinetik mit Km von 210 µM, vmax von 3 mM/min und kcat von 222 min-1 beobachtet. Diese Werte korrelieren mit den Werten der wenigen bekannten Diphenylcarbamat-spaltenden Abzyme. Die Beschleunigungsrate des Antikörpers N1-BC1-D11 betrug 10. Das ÜZA Hei3 hemmte die hydrolytische Aktivität. Dies beweist, dass die Hydrolyse in der Antigenbindungsstelle stattfindet. Weiter wurde zwischen der Antikörperkonzentration und der Umsatzgeschwindigkeit eine lineare Abhängigkeit festgestellt. Die thermodynamische Gleichtgewichtsdissoziationskonstante KD des Abzyms von 2,6 nM zeugt von einer sehr guten Affinität zum ÜZA. Hydrolytisch aktiv waren nur Antikörper, die gegen das Übergangszustandsanalogon Hei3 hergestellt worden waren. Es wird vermutet, dass die Hydrolyse der Benzylphenylcarbamate über einen Additions-Eliminierungsmechanismus unter Ausbildung eines tetraedrischen Übergangszustandes verläuft, dessen analoge Verbindung Hei3 ist. Im Rahmen der Generierung von Nachweisantikörpern zur Detektion der Substratabnahme bei der Hydrolyse wurden Anti-Diuron-Antikörper hergestellt. Einer der Antikörper (B91-CG5) ist spezifisch für das Herbizid Diuron und hat einen IC50-Wert von 0,19 µg/l und eine untere Nachweisgrenze von 0,04 µg/l. Ein anderer Antikörper (B91-KF5) reagiert kreuz mit einer Palette ähnlicher Herbizide. Mit diesen Antikörpern wurde ein empfindlicher Labortest, der ein Monitoring von Diuron auf Grundlage des durch die Trinkwasserverordnung festgeschriebenen Wertes für Pflanzenschutzmittel von 0,1 µg/l erlaubt, aufgebaut. Der Effekt der Anti-Diuron-Antikörper auf die Diuron-inhibierte Photosynthese wurde in vitro und in vivo untersucht. Es wurde nachgewiesen, dass sowohl in isolierten Thylakoiden, als auch in intakten Algen eine Vorinkubation der Anti-Diuron-Antikörper mit Diuron zur Inaktivierung seiner Photosynthese-hemmenden Wirkung führt. Wurde der Elektronentransport in den isolierten Thylakoiden oder in Algen durch Diuron unterbrochen, so führte die Zugabe der Anti-Diuron-Antikörper zur Reaktivierung der Elektronenübertragung. Attempts to produce catalytic antibodies for hydrolysis of arylcarbamates and arylureas: The aim of the investigations was to produce antibodies which are able to cleave herbicides resistant to naturally occuring enzymes. Structurally similar carbamate and urea derivatives were chosen for the experiments. Phosphonate derivatives were synthesized that mimick possible transition state analogues in structure and charge. Mice were immunized with 4 different derivatives after conjugating them to carrier proteins. 32 hybridomas were established that produce monoclonal antibodies binding to these derivatives. The possible cleavage of substrates was determined by immunoassays with monoclonal antibodies against the substrate and the products and with a photometric method based on dimethylaminocinammonaldehyde. The measuring of cleavage products was succeeded by an amperometric method. The enzyme sensor was based on immobilized tyrosinase which oxidizes p-chlorophenol and phenol. The antibodies N1-BC1-D11, N1-FA7-C4, N1-FA7-D12 und R3-LG2-F9 hydrolysed the benzylphenylcarbamates POCc18, POCc19 und Substance 27. The hydrolytic activity of these antibodies was also succeeded with HPLC. The catalytic antibody N1-BC1-D11 was investigated kinetically and thermodynamically. A Michaelis-Menten-Kinetic was observed (at pH 8.0 exhibited a Km 210 µM, a vmax 3 mM/min and a kcat 222 min-1). These values are in the range of the values obtained for the antibody-catalysed hydrolysis of diphenylcarbamates. The rate enhancement of N1-BC1 was 10. The reaction was completely inhibited by stoichiometric quantities of the transition state analogue Hei3. This is consistent with the affinity of the abzyme to Hei3 of 2.6 nM, determined by BIAcore assay. Only antibodies generated against Hei3 showed hydrolytic activity. The hydrolysis of benzylphenylcarbamates presumably occurs via an addition-elimination-Mechanism involving a tetrahedral intermediate. In summary, this work presents the first example of antibody-catalysed hydrolysis of benzylphenylcarbamates. Monoclonal anti-diuron antibodies were generated that bind to the herbicide diuron with an extremely low equilibrium dissociation constant. A sensitive immunoassay with a low detection limit of 0.2 nM for diuron was established. This is the most sensitive immunological method for detection of diuron known so far. These antibodies were also used in vitro and in vivo to prevent diuron-dependent inhibition of photosynthesis or to restore photosynthesis after inhibition. In isolated thylakoids prepared from spinach leaves (Spinacia oleracea L.) the diuron-inhibited Hill reaction was reconstituted immediately following the addition of the monoclonal antibodies. In an in vivo approach the photosynthetic oxygen evolution of the cell wall deficient mutant (cw 15) of the green alga Chlamydomonas reinhardtii Dangeard was monitored. The antibodies prevented the diuron-dependent inhibition of photosynthesis and restored photosynthesis after inhibition. Transgenic plants that synthesize and accumulate these antibodies or antibody fragments and are therefore diuron-resistant can be created.

  17. Further exclusion data for the Von Recklinghausen neurofibromatosis gene: a genetic linkage study of 19 polymorphic markers.

    PubMed Central

    Upadhyaya, M; Sarfarazi, M; Huson, S M; Harper, P S

    1987-01-01

    Linkage analysis on a panel of 15 Von Recklinghausen neurofibromatosis (VRNF) families with 19 polymorphic markers was carried out using the computer programme M-Link. Our findings have excluded VRNF from a significant proportion of the genome. PMID:3118035

  18. Baron Vincenz von Augustin and his Raketenbatterien: A history of Austrian rocketry in the 19th century

    NASA Technical Reports Server (NTRS)

    Winter, F. H.

    1977-01-01

    The pioneer work of Baron Vincenz von Augustin in the field of rocket weaponry is discussed. Austrian war rockets were also examined in their utilization throughout the 19th century in colonial uprisings and later colonial wars.

  19. Einfluss der Strontiumdotierung auf die Supraleitung von BaPb 0.75Bi 0.25O 3

    NASA Astrophysics Data System (ADS)

    Bredthauer, Jörg; Jansen, Martin

    1990-06-01

    ZusammenfassungBaPb 0.75Bi 0.25O 3 löst Strontium unter Bildung homogener Mischkristalle. Im Bereich 0 ? x ? 0.3 bezogen auf Ba 1- xSr xPb 0.75Bi 0.25O 3 ändert sich die pseudokubische Gitterkonstante von a = 429.9 pm auf a = 426.9 pm mit steigendem Strontiumgehalt. Mit dieser geringfügigen Änderung der Gitterkonstanten gehen deutliche Veränderungen der Parameter der Supraleitung einher. So verschiebt sich Tc ("onset") von 11.5 K auf 8 K bei x = 0.1. Der an reinen Proben von BaPb 0.75Bi 0.25O 3 (Pulver und Einkristalle) gefundene Meissner Effekt von 22.3% reduziert sich bereits bei x = 0.05 auf 12.4% bei 10.5 Gauss. Proben mit x = 0.3 sind nicht supraleitend.

  20. Georg von Bekesy, Nobel Laureate in Physiology, Experimental Physicist and Art Collector Was Born 100 Years Ago.

    ERIC Educational Resources Information Center

    Kovacs, Laszlo

    2001-01-01

    Describes the life and accomplishments of Georg von Bekesy. Discusses his educational background and research career, and describes his extensive work on the ear, particularly the inner ear or cochlea. (SAH)

  1. Quantitative biology of single neurons

    PubMed Central

    Eberwine, James; Lovatt, Ditte; Buckley, Peter; Dueck, Hannah; Francis, Chantal; Kim, Tae Kyung; Lee, Jaehee; Lee, Miler; Miyashiro, Kevin; Morris, Jacqueline; Peritz, Tiina; Schochet, Terri; Spaethling, Jennifer; Sul, Jai-Yoon; Kim, Junhyong

    2012-01-01

    The building blocks of complex biological systems are single cells. Fundamental insights gained from single-cell analysis promise to provide the framework for understanding normal biological systems development as well as the limits on systems/cellular ability to respond to disease. The interplay of cells to create functional systems is not well understood. Until recently, the study of single cells has concentrated primarily on morphological and physiological characterization. With the application of new highly sensitive molecular and genomic technologies, the quantitative biochemistry of single cells is now accessible. PMID:22915636

  2. Automated Quantitative Nuclear Cardiology Methods.

    PubMed

    Motwani, Manish; Berman, Daniel S; Germano, Guido; Slomka, Piotr

    2016-02-01

    Quantitative analysis of SPECT and PET has become a major part of nuclear cardiology practice. Current software tools can automatically segment the left ventricle, quantify function, establish myocardial perfusion maps, and estimate global and local measures of stress/rest perfusion, all with minimal user input. State-of-the-art automated techniques have been shown to offer high diagnostic accuracy for detecting coronary artery disease, as well as predict prognostic outcomes. This article briefly reviews these techniques, highlights several challenges, and discusses the latest developments. PMID:26590779

  3. RECENT ADVANCES IN QUANTITATIVE NEUROPROTEOMICS

    PubMed Central

    Craft, George E; Chen, Anshu; Nairn, Angus C

    2014-01-01

    The field of proteomics is undergoing rapid development in a number of different areas including improvements in mass spectrometric platforms, peptide identification algorithms and bioinformatics. In particular, new and/or improved approaches have established robust methods that not only allow for in-depth and accurate peptide and protein identification and modification, but also allow for sensitive measurement of relative or absolute quantitation. These methods are beginning to be applied to the area of neuroproteomics, but the central nervous system poses many specific challenges in terms of quantitative proteomics, given the large number of different neuronal cell types that are intermixed and that exhibit distinct patterns of gene and protein expression. This review highlights the recent advances that have been made in quantitative neuroproteomics, with a focus on work published over the last five years that applies emerging methods to normal brain function as well as to various neuropsychiatric disorders including schizophrenia and drug addiction as well as of neurodegenerative diseases including Parkinson’s disease and Alzheimer’s disease. While older methods such as two-dimensional polyacrylamide electrophoresis continued to be used, a variety of more in-depth MS-based approaches including both label (ICAT, iTRAQ, TMT, SILAC, SILAM), label-free (label-free, MRM, SWATH) and absolute quantification methods, are rapidly being applied to neurobiological investigations of normal and diseased brain tissue as well as of cerebrospinal fluid (CSF). While the biological implications of many of these studies remain to be clearly established, that there is a clear need for standardization of experimental design and data analysis, and that the analysis of protein changes in specific neuronal cell types in the central nervous system remains a serious challenge, it appears that the quality and depth of the more recent quantitative proteomics studies is beginning to shed light on a number of aspects of neuroscience that relates to normal brain function as well as of the changes in protein expression and regulation that occurs in neuropsychiatric and neurodegenerative disorders. PMID:23623823

  4. High speed quantitative digital microscopy

    NASA Technical Reports Server (NTRS)

    Castleman, K. R.; Price, K. H.; Eskenazi, R.; Ovadya, M. M.; Navon, M. A.

    1984-01-01

    Modern digital image processing hardware makes possible quantitative analysis of microscope images at high speed. This paper describes an application to automatic screening for cervical cancer. The system uses twelve MC6809 microprocessors arranged in a pipeline multiprocessor configuration. Each processor executes one part of the algorithm on each cell image as it passes through the pipeline. Each processor communicates with its upstream and downstream neighbors via shared two-port memory. Thus no time is devoted to input-output operations as such. This configuration is expected to be at least ten times faster than previous systems.

  5. Einfluss von Methaneinträgen auf die Hydrochemie des Münsterländer Kiessandzuges

    NASA Astrophysics Data System (ADS)

    Strobel, M.; Wisotzky, F.

    2009-03-01

    The Münsterländer Kiessandzug, a Quaternary trench structure, forms an important groundwater reservoir and is of great importance for the regional drinking water supply in north-west Germany (“Münsterland”). Since 2004, the Ruhr-University Bochum has been investigating the Aldruper Mark, evaluating the quantitative and qualitative potential for drinking water abstraction in the area. Due to intensive agricultural utilisation, a high nitrate influx into groundwater is expected. Therefore, this study was focused on contamination of groundwater with nitrate as well as on the nitrate degradation capacity of the sediments. However, present analyses show low nitrate concentrations and a reductive groundwater environment. To find the causes of these reducing conditions, it is necessary to examine the geological and hydrochemical situation with respect to the environment and the substratum of the investigated area: the MünsterländerCretaceous basin is underlain by Carboniferous sand- and mudstones which are degasing methane to some extent. This methane was detected in deep observation wells in the second aquifer of the Münsterländer Kiessandzug. In its central area, low concentrations of nitrate as well as low sulphate concentrations and positive ?34Ssulfate-isotope data indicate active sulphate reduction is occurring in the groundwater. Furthermore, a corresponding sulphide content was found in these Quaternary soils (“secondary pyrite”). An input of methane in the aquifer is discussed as a possible reason for sulphate reduction in the deep aquifer.

  6. Quantitative Prediction of Spacing Effects in Learning

    ERIC Educational Resources Information Center

    Reed, Adam

    1977-01-01

    The introduction of laboratory computers has facilitated investigation of quantitative theories in the investigation of memory. Data from a recent qualitative study was used to test two quantitative theories. The strength-resistance theory fitted the data quantitatively without significant deviations. Statistical tables and references are…

  7. Quantitative risk assessment system (QRAS)

    NASA Technical Reports Server (NTRS)

    Weinstock, Robert M (Inventor); Smidts, Carol S (Inventor); Mosleh, Ali (Inventor); Chang, Yung-Hsien (Inventor); Swaminathan, Sankaran (Inventor); Groen, Francisco J (Inventor); Tan, Zhibin (Inventor)

    2001-01-01

    A quantitative risk assessment system (QRAS) builds a risk model of a system for which risk of failure is being assessed, then analyzes the risk of the system corresponding to the risk model. The QRAS performs sensitivity analysis of the risk model by altering fundamental components and quantifications built into the risk model, then re-analyzes the risk of the system using the modifications. More particularly, the risk model is built by building a hierarchy, creating a mission timeline, quantifying failure modes, and building/editing event sequence diagrams. Multiplicities, dependencies, and redundancies of the system are included in the risk model. For analysis runs, a fixed baseline is first constructed and stored. This baseline contains the lowest level scenarios, preserved in event tree structure. The analysis runs, at any level of the hierarchy and below, access this baseline for risk quantitative computation as well as ranking of particular risks. A standalone Tool Box capability exists, allowing the user to store application programs within QRAS.

  8. Quantitative Characterization of Nanostructured Materials

    SciTech Connect

    Dr. Frank Bridges, University of California-Santa Cruz

    2010-08-05

    The two-and-a-half day symposium on the "Quantitative Characterization of Nanostructured Materials" will be the first comprehensive meeting on this topic held under the auspices of a major U.S. professional society. Spring MRS Meetings provide a natural venue for this symposium as they attract a broad audience of researchers that represents a cross-section of the state-of-the-art regarding synthesis, structure-property relations, and applications of nanostructured materials. Close interactions among the experts in local structure measurements and materials researchers will help both to identify measurement needs pertinent to “real-world” materials problems and to familiarize the materials research community with the state-of-the-art local structure measurement techniques. We have chosen invited speakers that reflect the multidisciplinary and international nature of this topic and the need to continually nurture productive interfaces among university, government and industrial laboratories. The intent of the symposium is to provide an interdisciplinary forum for discussion and exchange of ideas on the recent progress in quantitative characterization of structural order in nanomaterials using different experimental techniques and theory. The symposium is expected to facilitate discussions on optimal approaches for determining atomic structure at the nanoscale using combined inputs from multiple measurement techniques.

  9. Quantitative evaluation of Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Duchesne, S.; Frisoni, G. B.

    2009-02-01

    We propose a single, quantitative metric called the disease evaluation factor (DEF) and assess its efficiency at estimating disease burden in normal, control subjects (CTRL) and probable Alzheimer's disease (AD) patients. The study group consisted in 75 patients with a diagnosis of probable AD and 75 age-matched normal CTRL without neurological or neuropsychological deficit. We calculated a reference eigenspace of MRI appearance from reference data, in which our CTRL and probable AD subjects were projected. We then calculated the multi-dimensional hyperplane separating the CTRL and probable AD groups. The DEF was estimated via a multidimensional weighted distance of eigencoordinates for a given subject and the CTRL group mean, along salient principal components forming the separating hyperplane. We used quantile plots, Kolmogorov-Smirnov and χ2 tests to compare the DEF values and test that their distribution was normal. We used a linear discriminant test to separate CTRL from probable AD based on the DEF factor, and reached an accuracy of 87%. A quantitative biomarker in AD would act as an important surrogate marker of disease status and progression.

  10. Quantitative approaches to computational vaccinology.

    PubMed

    Doytchinova, Irini A; Flower, Darren R

    2002-06-01

    This article reviews the newly released JenPep database and two new powerful techniques for T-cell epitope prediction: (i) the additive method; and (ii) a 3D-Quantitative Structure Activity Relationships (3D-QSAR) method, based on Comparative Molecular Similarity Indices Analysis (CoMSIA). The JenPep database is a family of relational databases supporting the growing need of immunoinformaticians for quantitative data on peptide binding to major histocompatibility complexes and to the Transporters associated with Antigen Processing (TAP). It also contains an annotated list of T-cell epitopes. The database is available free via the Internet (http://www.jenner.ac.uk/JenPep). The additive prediction method is based on the assumption that the binding affinity of a peptide depends on the contributions from each amino acid as well as on the interactions between the adjacent and every second side-chain. In the 3D-QSAR approach, the influence of five physicochemical properties (steric bulk, electrostatic potential, local hydrophobicity, hydrogen-bond donor and hydrogen-bond acceptor abilities) on the affinity of peptides binding to MHC molecules were considered. Both methods were exemplified through their application to the well-studied problem of peptides binding to the human class I MHC molecule HLA-A*0201. PMID:12067414

  11. Clinical Utility of Quantitative Imaging

    PubMed Central

    Rosenkrantz, Andrew B; Mendiratta-Lala, Mishal; Bartholmai, Brian J.; Ganeshan, Dhakshinamoorthy; Abramson, Richard G.; Burton, Kirsteen R.; Yu, John-Paul J.; Scalzetti, Ernest M.; Yankeelov, Thomas E.; Subramaniam, Rathan M.; Lenchik, Leon

    2014-01-01

    Quantitative imaging (QI) is increasingly applied in modern radiology practice, assisting in the clinical assessment of many patients and providing a source of biomarkers for a spectrum of diseases. QI is commonly used to inform patient diagnosis or prognosis, determine the choice of therapy, or monitor therapy response. Because most radiologists will likely implement some QI tools to meet the patient care needs of their referring clinicians, it is important for all radiologists to become familiar with the strengths and limitations of QI. The Association of University Radiologists Radiology Research Alliance Quantitative Imaging Task Force has explored the clinical application of QI and summarizes its work in this review. We provide an overview of the clinical use of QI by discussing QI tools that are currently employed in clinical practice, clinical applications of these tools, approaches to reporting of QI, and challenges to implementing QI. It is hoped that these insights will help radiologists recognize the tangible benefits of QI to their patients, their referring clinicians, and their own radiology practice. PMID:25442800

  12. [Autopsy case of von Recklinghausen's disease associated with lung cancer, gastrointestinal stromal tumor of the stomach, and duodenal carcinoid tumor].

    PubMed

    Satoh, Miki; Wakabayashi, Osamu; Araya, Yoshikazu; Jinushi, Eisei; Yoshida, Fumiaki

    2009-09-01

    A 58-year-old man with von Recklinghausen's disease was admitted for further investigation of right chest pain. Chest X-ray revealed multiple emphysematous bullae in both lungs and a tumor shadow in the right upper lobe. Bronchofiberscopy was performed, but an adequate specimen was not obtained. The tumor was diagnosed as a non-small-cell lung cancer with direct invasion to the adjacent rib. Although chemotherapy and radiotherapy resulted in decrease in tumor size, the tumor subsequently increased in size and the patient died 14 months after the first admission. Autopsy revealed multiple emphysematous bullae, poorly differentiated adenosquamous cell carcinoma of the lung, gastrointestinal stromal tumor of the stomach, and duodenal carcinoid tumor. This case suggests the possibility that von Recklinghausen's disease associated with emphysematous bullae is a risk factor for lung cancer. It has also been suggested that the genetic abnormality responsible for von Recklinghausen's disease increases the risk for various types of malignancy. Although von Recklinghausen's disease is reportedly associated with various malignant tumors, it is quite rare for von Recklinghausen's disease to be associated with triple non-neurogenic tumors. Careful observation is mandatory for patients with von Recklinghausen's disease. PMID:19827584

  13. A Case of Acute Generalized Pustular Psoriasis of von Zumbusch Triggered by Hypocalcemia

    PubMed Central

    Guerreiro de Moura, Carlos Antônio Gusmão; de Assis, Luiz Henrique; Góes, Paulo; Rosa, Fabiana; Nunes, Victor; Gusmão, Ítalo Magalhães; Cruz, Constança Margarida Sampaio

    2015-01-01

    Psoriasis is an autoimmune disease triggered by different conditions in genetically susceptible people. It is characterized by variable cutaneous manifestations including localized or disseminated pustules. Generalized pustular psoriasis (GPP) has two main clinical forms: von Zumbusch psoriasis, characterized by severe erythrodermia and scaling skin after the resolution of pustules, and the annular form. GPP may also present severe extracutaneous manifestations including pneumonitis, heart failure and hepatitis. Old reports showed a relationship between hypoparathyroidism and hypocalcemia as triggers for GPP highlighting the importance of adequate workup of the patient and possible therapeutic changes in acute situations. Here, we present a case of severe von Zumbusch psoriasis with life-threatening complications triggered by severe hypocalcemia secondary to hypoparathyroidism successfully treated with aggressive calcium reposition. PMID:26955330

  14. [On the Awarding of the First Nobel Prize for Physiology or Medicine to Emil von Behring].

    PubMed

    Hansson, Nils; Enke, Ulrike

    2015-12-01

    In his will of 1895, the Swedish inventor Alfred Nobel laid the foundation for prizes in physics, chemistry, physiology or medicine, literature, and peace to those who had "conferred the greatest benefit on mankind" during the last year. The Nobel Prize is today widely considered as the most prestigious international symbol of scientific excellence, but it still is an exciting research question how it gained such prestige. Drawing on files from the Emil von Behring Archive in Marburg, Germany, and the Archive of the Nobel Assembly for Physiology or Medicine in Stockholm this essay aims at shedding light on why the first Nobel Prize for Physiology or Medicine in 1901 was awarded the German immunologist Emil von Behring, and how this decision was viewed at that time. This study is part of a research project that explores mechanisms leading to scientific recognition by using the example of the Nobel Prize for Physiology or Medicine. PMID:26676474

  15. Charakterisierung von CMOS RF Blöcken mittels Volterra-Reihen zur Optimierung des Designprozesses

    NASA Astrophysics Data System (ADS)

    Fei, B.; Darrat, A. H.; Mathis, W.

    2009-05-01

    Im Rahmen dieser Arbeit werden die Volterra-Reihen zur Analyse der Nichtlinearität in RF Schaltungen verwendet, um den Designprozess für RF Systeme zu optimieren. Die auf Volterra-Reihen basierende Nichtlinearitätsanalyse wurde in eine Matlab-Toolbox implementiert. Diese Toolbox kann mittels Volterra-Reihen die symbolische Berechnung der Nichtlinearitätsparameter (harmonische Verzerrungen und Intermodulationsverzerrungen) eines RF Blocks für eine gegebene Architektur und Technologie durchführen. Danach können die symbolische Ausdrücke der Nichtlinearitätsparameter in Abhängigkeit von den Architekturparametern und Technologieparametern erhalten werden. Dies ermöglicht die Beschränkung der Wertebereiche der Architekturparameter und die Überprüfung auf die Erfüllung der Nichtlinearitätsspezifikationen für unterschiedliche Kombinationen von Architekturen und Technologien. Somit ist eine Beschränkung der Klassen der Architekturen und Technologien möglich. Die Toolbox wurde zur Verdeutlichung auf einen Low Noise Amplifier (LNA) der Inductive Source Degeneration (ISD) Architektur angewandt. Zur Verifikation wurde diese LNA-Schaltung auch in Cadence SpectreRF Design Tool simuliert.

  16. Deafness due to bilateral endolymphatic sac tumours in a case of von Hippel-Lindau syndrome.

    PubMed Central

    Kempermann, G; Neumann, H P; Scheremet, R; Volk, B; Mann, W; Gilsbach, J; Laszig, R

    1996-01-01

    A case of bilateral endolymphatic sac tumours is reported. In a patient with von Hippel-Lindau syndrome, tumour growth in the right cerebellopontine angle caused deafness. The tumour was removed and classified as a metastasis from a thyroid carcinoma. However, on thyroidectomy no primary neoplasm could be found. Eight years later a similar tumour was operated on in the left petrosal bone. Histological appearance, immunocytochemical findings, and the clinical context gave evidence that the tumours had to be reclassified as endolymphatic sac tumours--extremely rare entities. The report supports the hypothesis, suggested by the few earlier case reports, that endolymphatic sac tumours could be one of the inherent tumour manifestations in von Hippel-Lindau syndrome. Images PMID:8795608

  17. Papillary neoplasm of the endolymphatic sac in a patient with von Hippel-Lindau disease.

    PubMed Central

    Delisle, M B; Uro, E; Rouquette, I; Yardeni, E; Rumeau, J L

    1994-01-01

    Glandular tumours involving the middle ear and the mastoid are rare, and distinguishing between adenoma and adenocarcinoma is difficult. Two distinct histopathological patterns are accepted. While their clinical presentation differs, both require primary surgical treatment and both have a high rate of local recurrence. The papillary form takes a more aggressive course and wider regional spread. This pattern occurs predominantly in women. Its microscopic appearance and clinical course have been extensively described by Heffner who considered it as "low-grade adenocarcinoma of probable endolymphatic sac origin". A few cases have been associated with von Hippel-Lindau disease. The case of a 32 year old black woman is described. It is suggested that papillary adenocarcinoma of the endolymphatic sac should be considered in the spectrum of neoplasms seen in von Hippel-Lindau disease. Images PMID:7962613

  18. Commutation of Projections and Characterization of Traces on von Neumann Algebras. III

    NASA Astrophysics Data System (ADS)

    Bikchentaev, A. M.

    2015-12-01

    We obtain new necessary and sufficient commutation conditions for nonnegative operators and projections in terms of operator inequalities. It is shown that in the general case in this inequalities the projections cannot be replaced by arbitrary nonnegative operators with preservation of operators commutativity. We also present new necessary and sufficient commutation conditions for projections in terms of operator inequalities. These inequalities are applied for trace characterization on von Neumann algebras in the class of all positive normal functionals. We also consider the following problems: I. Characterization of traces among arbitrary weights on von Neumann algebras. II. Characterization of tracial functionals among all positive linear functionals on C ∗-algebras. III. Characterization of commutativity for C ∗-algebras.

  19. New three-dimensional plastic potentials for porous solids with a von Mises matrix

    NASA Astrophysics Data System (ADS)

    Cazacu, Oana; Revil-Baudard, Benoit

    2015-02-01

    In this paper, new 3-D plastic potentials for a porous solid with a von Mises matrix are obtained. First, a strain rate based potential is derived, the noteworthy result being its centro-symmetry. Moreover, it is revealed that the couplings between invariants are very specific, the most important influence of the third invariant being for axisymmetric states. It is demonstrated that the exact stress-based potential of the porous material should have the same key properties. Furthermore, it is deduced a new analytic 3-D stress-based potential that satisfies these properties. Compared to the existing criteria for porous solids with a von Mises matrix, this model is the only one that captures the specific couplings between all stress invariants and is exact for axisymmetric states.

  20. Meningeal Supratentorial Hemangioblastoma in a Patient with Von Hippel-Lindau Disease Mimicking Angioblastic Menigioma

    PubMed Central

    Kim, Hoon; Park, Ik-Seong

    2013-01-01

    Hemangioblastomas are sporadic tumors found in the cerebellum or spinal cord. Supratentorial hemangioblastomas are rare, and those with meningeal involvement are extremely rare and have been reported in only approximately 130 patients. Here, we report the case of a 51-year-old female patient with supratentorial meningeal hemangioblastoma detected 5 years after surgical resection of an infratentorial hemangioblastoma associated with von Hippel-Lindau disease. Patients with von Hippel-Lindau syndrome are at risk for developing multiple hemangioblastomas, with new tumor formation and growth and possible meningeal infiltration. Regular lifelong follow-up in at-risk patients is recommended and should include the differential diagnosis of dural-based tumors such as angioblastic meningioma and metastatic renal cell carcinoma. PMID:24379949

  1. [Acquired von Willebrand's disease type 2A following arteriovenous fistula for haemodialysis?].

    PubMed

    Leimkühler, K; Bach, F; Kuhlmann, S; Feidicker, B; Heim, M U; Susemihl, C; Schmidt, B; Mertzlufft, F

    2011-05-01

    Acquired von Willebrand's disease (aVWD) is considered to be an underestimated cause of unexplained bleeding. Adsorption of von Willebrand factor (VWF) to tumour cells or hydroxyethyl starch and elimination of VWF by autoantibodies as well as shear stress-induced mechanical alteration of VWF with concomitant cleavage by enzymes may lead to an acquired deficiency of VWF and a bleeding disorder. We report a 39-year-old woman who developed spontaneous bleeding five years after surgical creation of an arteriovenous fistula (AVF) for haemodialysis treatment. AVWD type 2A was diagnosed after successful renal transplantation. One year after surgical closure of the AVF, the aVWD could not be verified again. Thus, the aVWD may have developed because of altered blood flow and shear stress inside the arteriovenous fistula. PMID:21152674

  2. Untersuchung der Richtwirkung der Einkopplung von ebenen Wellen in eine Leitung

    NASA Astrophysics Data System (ADS)

    Magdowski, M.; Vick, R.

    2013-07-01

    Elektrische Leitungen und Kabel stellen häufig die Haupteinfallstore für elektromagnetische Felder in die daran angeschlossenen Geräte und Systeme dar. Für die Einkopplung einer ebenen Welle kann der in eine Leitung eingekoppelte Strom unter bestimmten Voraussetzungen mit Hilfe der Leitungstheorie sehr effizient bestimmt werden. Er hängt dabei von den Abmessungen der Leitung, den Leitungsabschlüssen sowie der Amplitude, der Wellenlänge und der Einfallsrichtung der ebenen Welle ab. In dieser Arbeit wird die Abhängigkeit der Einkopplung von der Einfallsrichtung näher untersucht. Dazu werden Richtdiagramme der Einkopplung berechnet, dargestellt und hinsichtlich der mittleren und maximalen Einkopplung über alle Einfallsrichtungen und Polarisationen ausgewertet. Die Ergebnisse werden genutzt, um die maximale Direktivität der Einkopplung in eine Leitung zu bestimmen. Fasst man die Einkopplung externer Felder in eine Leitung als einen Störfestigkeitstest auf, so kann die maximale Direktivität benutzt werden, um einen Vergleich zwischen unterschiedlichen Messumgebungen wie Absorberhallen und Modenverwirbelungskammern herzustellen.

  3. Synthese von analogen Filtern auf einer rekonfigurierbaren Hardware-Architektur mittels eines Genetischen Algorithmus

    NASA Astrophysics Data System (ADS)

    Trendelenburg, S.; Becker, J.; Henrici, F.; Manoli, Y.

    2008-05-01

    Rekonfigurierbare Analog-Arrays (FPAAs) sind der Versuch, die Vorteile der aus der digitalen Welt bekannten FPGAs (Flexibilität, Entwurfsgeschwindigkeit) auch für analoge Anwendungen verfügbar zu machen. Aufgrund der Vielfalt der analogen Schaltungstechnik ist die Abbildung von vorgegebenen Schaltungskonzepten auf eine FPAA-Architektur nicht immer einfach lösbar. Diese Arbeit stellt einen neuen Ansatz für die Synthese von Filtern auf einer FPAA-Architektur für zeitkontinuierliche Analogfilter mittels eines Genetischen Algorithmus (GA) vor. Anhand eines Matlab-Modells des FPAA, das eine gute übereinstimmung mit Simulationen des FPAA auf Transistorebene aufweist, wurde gezeigt, dass eine große Vielzahl verschiedener Filterstrukturen auf dieser Architektur dargestellt werden kann. Daraufhin wurde ein Genetischer Algorithmus entwickelt, der es erlaubt, aus einer gegebenen Filterspezifikation Konfigurationsdatensätze zu synthetisieren, die den gewünschten Filter auf die FPAA-Architektur abbilden.

  4. Modeling individual specific fish length from capture-recapture data using the von Bertalanffy growth curve.

    PubMed

    Schofield, Matthew R; Barker, Richard J; Taylor, Peter

    2013-12-01

    We use Bayesian methods to explore fitting the von Bertalanffy length model to tag-recapture data. We consider two popular parameterizations of the von Bertalanffy model. The first models the data relative to age at first capture; the second models in terms of length at first capture. Using data from a rainbow trout Oncorhynchus mykiss study we explore the relationship between the assumptions and resulting inference using posterior predictive checking, cross validation and a simulation study. We find that untestable hierarchical assumptions placed on the nuisance parameters in each model can influence the resulting inference about parameters of interest. Researchers should carefully consider these assumptions when modeling growth from tag-recapture data. PMID:24117027

  5. Jahre Entwicklung der Instandhaltung - von der ausfallorientierten Instandhaltung zum gemeinsamen TPM und RCM

    NASA Astrophysics Data System (ADS)

    Iske, Friedhelm

    Zur Einleitung meines Beitrages möchte ich von einem Gespräch mit einem Mitarbeiter berichten, das ich als junger Vorgesetzter einer Instandhaltungsgruppe 1988 führte. Der engagierte Mitarbeiter feierte damals sein vierzigjähriges Dienstjubiläum und war stolz auf das von ihm Geleistete sowie auf den besonderen Einsatz seiner Altersgruppe, die nach dem Zweiten Weltkrieg das Werk wieder aufgebaut hatte. Auf meine Frage, was denn damals die erste Aufgabe in der Firma war, bekam ich kurz und knapp und mit einer Selbstverständlichkeit die selbstbewusste Antwort: "Unser Pferd füttern und mit dem Pferd die innerbetrieblichen Transporte erledigen“. Als junger, technisch orientierter Vorgesetzter war ich über diese Antwort sehr überrascht. Gedanklich weit entfernt war die Vorstellung, dass in der Vergangenheit Transporte mit einem Pferd erledigt wurden.

  6. Up to date concepts about Von Willebrand disease and the diagnose of this hemostatic disorder

    PubMed Central

    Buga-Corbu, I; Arion, C

    2014-01-01

    Abstract The authors review the current data in literature regarding the recent knowledge about hemostase, coagulation and clinical and laboratory diagnostic algorithms of hemostatic disorders. They also present the pathological classification of bleeding disorders - the basis to clinical approach of these diseases. Abbreviations: AD=autosomal dominant; Ag=antigen; DNA=deoxyribonucleic acid; ADAMTS13=serum metalloproteinase; AR=autosomal recessive; Arg=arginine; RNA=ribonucleic acid; VWD=von Willebrand disease; Cys=cysteine; C1—C9=factors of the seric complement; ELISA=enzyme linked immuno assay; FI---FXIII=plasmatic factors of coagulation; Glu=glutamines; Pg=platelet glycoprotein; HMW=high molecular weight; IL=interleukin; SLE=systemic lupus erythematosus; Met=methionine; PFA=automated study test of platelets aggregation; RCo=ristocetin cofactor; RI PA=ristocetin induced platelet aggregation; Tyr=tyrosine; VWF= von Willebrand factor PMID:25408749

  7. L'atteinte vésicale au cours de la neurofibromatose de Von Recklinghausen

    PubMed Central

    Benazzouz, Mohamed Hicham; Hajjad, Tilila; Essatara, Younes; El Sayegh, Hachem; Iken, Ali; Benslimane, Lounis; Nouini, Yassine

    2014-01-01

    La neurofibromatose de type 1 ou maladie de Von Recklinghausen est une maladie génétique autosomique dominante en rapport avec des mutations dans le gène suppresseur de tumeur NF1. L'atteinte uro-génitale au cours de cette maladie est rare et moins de 80 cas ont été rapportés à ce jour dans la littérature mondiale. Les auteurs rapportent un nouveau cas d'atteinte vésicale découverte fortuitement au cours du suivi d'une patiente atteinte de la maladie de Von Recklinghausen. A travers cette observation et une revue de la littérature les auteurs discutent également les difficultés diagnostiques, thérapeutiques ainsi que les modalités de suivi dans cette maladie. PMID:25328590

  8. [Color vision of animals. Views from Carl von Hess to today].

    PubMed

    Autrum, H

    1990-08-01

    In 1912 Carl von Hess, Professor of Ophthalmology in Munich, published the first comprehensive monograph on color vision in animals. He concluded that fish and all invertebrates are color-blind. At the same time, Karl von Frisch demonstrated that fish and honeybees can see and distinguish colors. The theory of trichromacy (Young-Helmholtz) is valid only for primates and some (e.g., bees) but not all insects. Almost all animals can see colors, and the eyes of some invertebrates contain up to 11 types of spectrally different receptor cells. Most animals - with the exception of mammals and cephalopods - can see ultraviolet and/or far red light. Therefore, many animals perceive more colors than human beings. PMID:2243484

  9. A Laboratory Phenotype/Genotype Correlation of 1167 French Patients From 670 Families With von Willebrand Disease: A New Epidemiologic Picture.

    PubMed

    Veyradier, Agnès; Boisseau, Pierre; Fressinaud, Edith; Caron, Claudine; Ternisien, Catherine; Giraud, Mathilde; Zawadzki, Christophe; Trossaert, Marc; Itzhar-Baïkian, Nathalie; Dreyfus, Marie; d'Oiron, Roseline; Borel-Derlon, Annie; Susen, Sophie; Bezieau, Stéphane; Denis, Cécile V; Goudemand, Jenny

    2016-03-01

    von Willebrand disease (VWD) is a genetic bleeding disease due to a defect of von Willebrand factor (VWF), a glycoprotein crucial for platelet adhesion to the subendothelium after vascular injury. VWD include quantitative defects of VWF, either partial (type 1 with VWF levels <50 IU/dL) or virtually total (type 3 with undetectable VWF levels) and also qualitative defects of VWF (type 2 variants with discrepant antigenic and functional VWF levels). The most bleeding forms of VWD usually do not concern type 1 patients with the mildest VWF defects (VWF levels between 30 and 50 IU/dL).The French reference center for VWD performed a laboratory phenotypic and genotypic analysis in 1167 VWD patients (670 families) selected by their basic biologic phenotype: type 3, type 2, and type 1 with VWF levels <30 IU/dL. In these patients indeed, to achieve an accurate diagnosis of VWD type and subtype is crucial for the management (treatment and genetic counseling).A phenotype/genotype correlation was present in 99.3% of cases; 323 distinct VWF sequence variations (58% of novel) were identified (missense 67% versus truncating 33%). The distribution of VWD types was: 25% of type 1, 8% of type 3, 66% of type 2 (2A: 18%, 2B: 17%, 2M: 19%, 2N: 12%), and 1% of undetermined type. Type 1 VWD was related either to a defective synthesis/secretion or to an accelerated clearance of VWF. In type 3 VWD, bi-allelic mutations of VWF were found in almost all patients. In type 2A, the most frequent mechanism was a hyper-proteolysis of VWF. Type 2B showed 85% of patients with deleterious mutations (distinct from type 2B New York). Type 2M was linked to a defective binding of VWF to platelet glycoprotein Ib or to collagen. Type 2N VWD included almost half type 2N/3.This biologic study emphasizes the complex mechanisms for both quantitative and qualitative VWF defects in VWD. In addition, this study provides a new epidemiologic picture of the most bleeding forms of VWD in which qualitative defects are predominant. PMID:26986123

  10. Dr. von Braun and Dr. Stuhlinger With a Model of the Nuclear-Electric Vehicles

    NASA Technical Reports Server (NTRS)

    2004-01-01

    In this photo, taken at the Walt Disney Studios in California, Dr. Wernher von Braun and Dr. Ernst Stuhlinger are shown discussing the concepts of nuclear-electric spaceships designed to undertake the mission to the planet Mars. As a part of the Disney 'Tomorrowland' series on the exploration of space, the nuclear-electric vehicles were shown in the last three television films, entitled 'Mars and Beyond,' which first aired in December 1957.

  11. ["Living with the bomb" - Carl Friedrich von Weizsäcker's path from physics to politics].

    PubMed

    Walker, Mark

    2014-01-01

    Carl Friedrich von Weizsäcker spanned a spectrum from physics to politics, with philosophy in-between. This chapter surveys the most controversial part of his career, including his work on nuclear weapons and participation in cultural propaganda during the Second World War, his subsequent active political engagement during the postwar Federal German Republic, in particular the role of nuclear weapons, and his participation in myths surrounding Hitler's Bomb". PMID:24974611

  12. Werner Heisenberg and Carl Friedrich Freiherr von Weizsäcker: A Fifty-Year Friendship*

    NASA Astrophysics Data System (ADS)

    Cassidy, David C.

    2015-03-01

    This paper follows Werner Heisenberg and Carl Friedrich von Weizsäcker during their fifty-year friendship from 1926, when they first met in Copenhagen, to Heisenberg's death in Munich in 1976. The relationship underwent profound changes during that period, as did physics, philosophy, and German society and politics, all of which exerted important influences on their lives, work, and interactions with each other. The nature of these developments and their impact are explored in this paper.

  13. Verknüpfung von DQ-Indikatoren mit KPIs und Auswirkungen auf das Return on Investment

    NASA Astrophysics Data System (ADS)

    Block, Frank

    Häufig ist nicht klar, welche Beziehungen zwischen Datenqualitätsindikatoren (DQI, Definition folgt weiter unten) und Key Performance Indicators (KPI, s. Abschnitt 1.3 für weitere Details) eines Unternehmens oder einer Organisation bestehen. Dies ist insbesondere deshalb von Bedeutung, da die Kenntnis dieser Beziehungen maßgeblich die Ausprägung eines Datenqualitätsprojekts beeinflusst. Sie ist als Entscheidungsgrundlage unabdingbar und gibt Antworten auf folgende Fragen: Was kostet unserem Unternehmen/unserer Organisation1 schlechte Datenqualität? Können wir uns das leisten?

  14. Differential proteolytic activation of factor VIII-von Willebrand factor complex by thrombin

    SciTech Connect

    Hill-Eubanks, D.C.; Parker, C.G.; Lollar, P. )

    1989-09-01

    Blood coagulation factor VIII (fVIII) is a plasma protein that is decreased or absent in hemophilia A. It is isolated as a mixture of heterodimers that contain a variably sized heavy chain and a common light chain. Thrombin catalyzes the activation of fVIII in a reaction that is associated with cleavages in both types of chain. The authors isolated a serine protease from Bothrops jararacussu snake venom that catalyzes thrombin-like heavy-chain cleavage but not light-chain cleavage in porcine fVIII as judged by NaDodSO{sub 4}/PAGE and N-terminal sequence analysis. Using a plasma-free assay of the ability of activated {sup 125}I-fVIII to function as a cofactor in the activation of factor X by factor IXa, they found that fVIII is activated by the venom enzyme. The venom enzyme-activated fVIII was isolated in stable form by cation-exchange HPLC. von Willebrand factor inhibited venom enzyme-activated fVIII but not thrombin-activated fVIII. These results suggest that the binding of fVIII to von Willebrand factor depends on the presence of an intact light chain and that activated fVIII must dissociate from von Willebrand factor to exert its cofactor effect. Thus, proteolytic activation of fVIII-von Willebrand factor complex appears to be differentially regulated by light-chain cleavage to dissociate the complex and heavy-chain cleavage to activate the cofactor function.

  15. Stufenweise Integration von eLearning an der Technischen Universität München

    NASA Astrophysics Data System (ADS)

    Pätzold, Sebastian; Graf, Stephan; Gergintchev, Ivan; Pongratz, Hans; Rathmayer, Sabine

    Der vorliegende Beitrag beschreibt als Best Practice Beispiel die stufenweise Integration eines Learning Management Systems (LMS) in die Infrastruktur von Information und Kommunikation (IuK) der Technischen Universität München (TUM). Dabei wird sowohl die Konsolidierung mehrfach angebotener Funktionalitäten und Dienste in den verschiedenen Portalen der Universität als auch die sukzessive Optimierung der Abläufe aufgezeigt. Gleichzeitig wird auf zukünftige weitere Entwicklungen hin zu einer vollständigen Integration der IuK, aber auch auf die Probleme in den unterschiedlichen Stadien der Entwicklung eingegangen.

  16. Relationship between ABO blood group and von Willebrand factor levels: from biology to clinical implications

    PubMed Central

    Franchini, Massimo; Capra, Franco; Targher, Giovanni; Montagnana, Martina; Lippi, Giuseppe

    2007-01-01

    Although a number of studies have demonstrated the influence of ABO blood group on plasma levels of von Willebrand factor (VWF), the nature of this association and its clinical importance is still largely unknown. In this review, the most recent advances in our understanding of the mechanisms by which ABO blood group determines plasma VWF levels and their clinical impact will be discussed. PMID:17894864

  17. Dynamic contact problem for a bridge modeled by a viscoelastic full von Kármán system

    NASA Astrophysics Data System (ADS)

    Bock, I.; Jarušek, J.

    2010-10-01

    The existence of solutions is proved for a full system of dynamic von Kármán equations expressing vibrations of geometrically nonlinear viscoelastic plate, the viscosity of which has the character of a short memory. The system models the behaviour of a bridge. The in-plane acceleration terms are taken into account. The boundary contact conditions for plane displacements and possibly the contact with the rigid support are considered.

  18. Finite element approximation of an optimal control problem for the von Karman equations

    NASA Technical Reports Server (NTRS)

    Hou, L. Steven; Turner, James C.

    1994-01-01

    This paper is concerned with optimal control problems for the von Karman equations with distributed controls. We first show that optimal solutions exist. We then show that Lagrange multipliers may be used to enforce the constraints and derive an optimality system from which optimal states and controls may be deduced. Finally we define finite element approximations of solutions for the optimality system and derive error estimates for the approximations.

  19. An efficient method for calculating RMS von Mises stress in a random vibration environment

    SciTech Connect

    Segalman, D.J.; Fulcher, C.W.G.; Reese, G.M.; Field, R.V. Jr.

    1998-02-01

    An efficient method is presented for calculation of RMS von Mises stresses from stress component transfer functions and the Fourier representation of random input forces. An efficient implementation of the method calculates the RMS stresses directly from the linear stress and displacement modes. The key relation presented is one suggested in past literature, but does not appear to have been previously exploited in this manner.

  20. Lagenwechsel minimieren - oder das Bohren von Löchern in Leiterplatten

    NASA Astrophysics Data System (ADS)

    Grötschel, Martin; Koch, Thorsten; Hoàng, Nam Dũng

    Diese Aufgabe behandelt ein Problem, das beim Entwurf von Leiterplatten auftritt. Die Aufgabe ist rein kombinatorischer Natur, man benötigt keine Kenntnisse der Elektromechanik. Einfache Leiterplatten haben zwei Seiten (auch Lagen genannt), auf die Strom leitende Bahnen (genannt Leiterbahnen) aufgebracht werden können. Wir nennen diese Lagen obere und untere Lage. Abbildung 1 zeigt eine unbestückte Leiterplatte und ihren "Schatten", der die Löcher in der Leiterplatte sichtbar macht.

  1. Benard-von Karman Vortex Street in a Bose-Einstein Condensate

    SciTech Connect

    Sasaki, Kazuki; Suzuki, Naoya; Saito, Hiroki

    2010-04-16

    Vortex shedding from an obstacle potential moving in a Bose-Einstein condensate is investigated. Long-lived alternately aligned vortex pairs are found to form in the wake, which is similar to the Benard-von Karman vortex street in classical viscous fluids. Various patterns of vortex shedding are systematically studied and the drag force on the obstacle is calculated. It is shown that the phenomenon can be observed in a trapped system.

  2. [Potenzielle Inanspruchnahme von Gesundheitsprofessionen durch privat Versicherte unter Berücksichtigung komplementärmedizinischer Versorgungsleistungen].

    PubMed

    Ostermann, Thomas; Vollmar, Horst Christian; Raak, Christa; Jacobi, Frank; Büssing, Arndt; Matthiessen, Peter F

    2015-01-01

    Hintergrund: Patientenpräferenzen gewinnen zunehmend an Bedeutung und werden auch in der Versorgungsforschung vermehrt untersucht. Ziel der Arbeit war es, Aufschlüsse über die potenzielle Inanspruchnahme von Gesundheitsprofessionen unter Berücksichtigung komplementärmedizinischer Versorgungsleistungen bei Versicherten einer privaten Krankenkasse zu erhalten. Methodik: Auf der Basis von 7 hypothetischen Beschwerden (Brustdruck, Allergie, Verdauungsbeschwerden, depressive Verstimmung, Knieschwellung, Suchtmittelreduzierung sowie Kind mit fieberhaftem Infekt) sollten die Befragten ihre erste und zweite Wahl des Ansprechpartners nennen. Als Optionen standen zur Wahl: schulmedizinisch orientierter Hausarzt, schulmedizinisch orientierter Facharzt, naturheilkundlich spezialisierter Arzt (NHK-Arzt), Heilpraktiker, Apotheker und sonstige. Übereinstimmungen in Bezug auf die Erstpräferenzen wurden mithilfe des Kappa-Koeffizienten berechnet. Ergebnisse: 1960 Versicherte (74,1% männlich, mittleres Alter 62,4 ± 10,2 Jahre) gaben vollständige Angaben zu ihren Präferenzen an. Bei allen Beschwerden würden die Versicherten primär den schulmedizinisch orientierten Hausarzt und erst im Folgenden einen Facharzt präferieren. Lediglich bei der Behandlung von Allergien (12,5%) und Depressionen (11,8%) oder bei einer Suchtmittelreduzierung (18,6%) würde auch ein NHK-Arzt verstärkt als Erstkontakt zurate gezogen werden. Bei der Suchtmittelentwöhnung spielt auch die Kompetenz des Heilpraktikers in der Zweitwahl eine größere Rolle (15,5%). Vor allem die Angaben zu Konsultationen bei depressiven Verstimmungen, Allergien, Verdauungsbeschwerden und Angina pectoris besaßen mit Kappa-Werten von über 0,5 ein hohes Übereinstimmungspotenzial. Eine Sensitivitätsanalyse in Bezug auf Geschlecht und Bildung zeigte darüber hinaus, dass bei einer Homogenisierung des Kollektivs die Übereinstimmungswerte deutlich höher werden. Diskussion: Ungeachtet der Beschwerdeart scheint für die Mehrheit der Befragten der konventionelle Haus- bzw. Facharzt erster Ansprechpartner bei gesundheitlichen Problemen zu sein, während eine naturheilkundliche Kompetenz nur bei bestimmten Erkrankungen relevant zu sein scheint. PMID:26840419

  3. Von Frey's hairs--a review of their technology and use--a novel automated von Frey device for improved testing for hyperalgesia.

    PubMed

    Lambert, Geoffrey A; Mallos, George; Zagami, Alessandro S

    2009-03-15

    We describe a device which allows the mechanical sensitivity of trigeminovascular sensory neurons to be monitored over extended time periods. The device can be used to stimulate either the skin or dura mater and consists of a solenoid-driven plunger to which are fixed interchangeable von Frey hairs. The solenoid can be attached to a stereotaxic carrier and mounted on a stereotaxic frame to allow precise positioning over the receptive field. The device is driven from the synchronization signals of a standard stimulator via TTL circuitry and a relay driver, to allow stimulation by a single or multiple stimuli. The advantages of the device over manual stimulation include the reproducibility of the site of stimulation; the ability to apply a known force for a known time; the ability to measure response latencies to millisecond precision and to compare them to latencies to other stimuli and; easy interface with computer-control. We discuss some of the drawbacks of the von Frey system as usually used and illustrate the use of the new device with results from experiments on peripherally induced sensitization. PMID:19041344

  4. An Alternative to Von Glasersfeld's Subjectivism in Science Education: Deweyan Social Constructivism

    NASA Astrophysics Data System (ADS)

    Garrison, Jim

    An influential view of constructivism in science and mathematics educational research and practice is that of Ernst von Glasersfeld. It is a peculiarly subjectivist form of constructivism that should not be attractive to science and mathematics educators concerned with retaining some sort of realism that leaves room for objectivity. The subjectivist constructivism of von Glasersfeld also becomes entangled in untenable mind/body and subject/object dualisms. Finally, these dualisms are unnecessary for social constructivism. I will provide one example of a social constructivist alternative to social constructivism, that of the pragmatic philosopher JohnDewey. In presenting Deweys position I will appeal to Ockhams razor, that is, the admonition not to multiply entities beyond necessity, to shave off the needless mentalistic and psychic entities that lead von Glasersfeld into his subjectivism and dualism.In outward forms, experimental science is infinitely varied. In principle, it is simple. We know an object when we knowhow it is made, and we know how it is made in the degree in which we ourselves make it.

  5. Otto von Gericke (1602-1686) and his pioneering vacuum experiments.

    PubMed

    Harsch, Viktor

    2007-11-01

    The German scholar Otto von Guericke (1602-1686) is regarded as one of the most prominent figures of the scientific revolution in the 17th century. A politician, physicist, engineer, and natural philosopher, von Guericke invented the world's first air pump in 1650. By performing and interpreting some pioneering vacuum experiments, he made important contributions to the basic principles of the physics of fluids and gases. He is most recognized for his so-called Magdeburg experiments, in which two copper hemispheres were placed together, the interior evacuated, and two teams of horses were unable to pull the evacuated hemispheres apart until the air was readmitted. In this way in 1654 he first demonstrated the enormous power of the atmosphere. Through this and other experiments, Otto von Guericke significantly contributed to the understanding of high altitude physiology, and was the first to experiment with an artificial vacuum. However, it took more than three centuries before his pioneering book, Experimenta Nova Magdeburgica de Vacua Spatio (1672), was translated into English in 1994, bringing his genius, scientific ideas, and philosophical understanding to a wider audience. PMID:18018443

  6. From Mill via von Kries to Max Weber: Causality, Explanation, and Understanding

    NASA Astrophysics Data System (ADS)

    Heidelberger, Michael

    In the second part of his "Critical studies in the logic of the cultural sciences" published in 1906, which carries the title "Objective possibility and adequate causation in historical explanation" (Weber 1906, 164-188/266-290)1 Max Weber (1864-1920) wrote that he feels "almost embarrassed in view of the extent to which here again, as in so much of the preceding argument, I am 'plundering' von Kries' ideas" (Weber 1906, 186/288).2 Weber thus admits a very strong influence on his approach by the physiologist, philosopher, and theoretician of probability, von Kries (1853-1928), who was for sometime his colleague in Freiburg in southwest Germany. Von Kries had suggested a legal criterion for attributing a deed to an agent that exerted a strong influence on German civil law and was also taken up by the legal system of other countries. This earned him the title of an honorary doctor of the law faculty of the University of Erlangen in 1897.

  7. Invited commentary: The context and challenge of von Pettenkofer's contributions to epidemiology.

    PubMed

    Oppenheimer, Gerald M; Susser, Ezra

    2007-12-01

    Max von Pettenkofer is largely remembered for swallowing cholera vibrio, trying thereby to falsify the claim of his rival, the contagionist Robert Koch, that the bacillus he had isolated was cholera's sufficient cause. In this issue of the American Journal of Epidemiology, Alfredo Morabia reminds us that von Pettenkofer was more than this futile gesture. He was a 19th century public health leader whose multifactorial theory of cholera etiology deeply influenced the dominant anticontagionist school of disease transmission. His authority was undercut by the massive 1892 cholera epidemic in Hamburg, Germany. As it took off, the German government sent in Koch, who successfully contained the epidemic through interventions that von Pettenkofer regularly repudiated-quarantine, disinfection, and the boiling of water. The authors situate the antagonism between these two individuals within a broader scientific and political context that includes the evolution of miasma theory and debates over the role of governments confronted by epidemic disease. They also note that Koch's approach, which focused narrowly on the agent and its eradication, was missing key elements required for applying germ theory to public health. As scientists later incorporated biologic, host, and environmental factors into the germ theory paradigm, they reintroduced some of the complexity that had previously characterized the miasma model. PMID:17934199

  8. Interactions between the surface gravity waves and the Von Karman streets: a numerical study

    NASA Astrophysics Data System (ADS)

    Gunnoo, Hans; Bennis, Anne-Claire; Rivier, Aurélie; Abcha, NIzar; Ezersky, Alexander

    2015-04-01

    The growth of renewable energy over the past decade is impressive. Offshore wind farms are planned to construct along the site of Courseulles s/mer (Normandy, France) in 2018. The ofelia project leads to study the environmental impacts of the offshore wind farms in the Channel. In parallel with the regional modeling of the changes in hydrodynamic and in sediment transport due to monopiles (Rivier et al., 2014), studies at local scales are also carried out. Laboratory experiments show that the resonance between the surface gravity waves and the Von Karman streets leads to modify the synchronisation of the vortex (Gunnoo et al., 2014). Numerical simulations are performed to reproduce this mechanism. The CFD code, IHFOAM, based on an OpenFoam Kernel, allows to simulate the wave-current interactions at local scales. First, bi-dimensional and three-dimensional simulations without waves are set-up to validate our modeling plateform. The well-known Von Karman streets are obtained. Results are in agreement with the experimental data. Second, waves are included in the simulations. The free-surface is explicitely solved by the Volume Of Fluid method. Regular and irregular wave spectrums are tested. Changes in Von Karman Streets due to waves are observed. In the future, some comparisons with the experimental results will be done.

  9. A Quantitative Fitness Analysis Workflow

    PubMed Central

    Lydall, D.A.

    2012-01-01

    Quantitative Fitness Analysis (QFA) is an experimental and computational workflow for comparing fitnesses of microbial cultures grown in parallel1,2,3,4. QFA can be applied to focused observations of single cultures but is most useful for genome-wide genetic interaction or drug screens investigating up to thousands of independent cultures. The central experimental method is the inoculation of independent, dilute liquid microbial cultures onto solid agar plates which are incubated and regularly photographed. Photographs from each time-point are analyzed, producing quantitative cell density estimates, which are used to construct growth curves, allowing quantitative fitness measures to be derived. Culture fitnesses can be compared to quantify and rank genetic interaction strengths or drug sensitivities. The effect on culture fitness of any treatments added into substrate agar (e.g. small molecules, antibiotics or nutrients) or applied to plates externally (e.g. UV irradiation, temperature) can be quantified by QFA. The QFA workflow produces growth rate estimates analogous to those obtained by spectrophotometric measurement of parallel liquid cultures in 96-well or 200-well plate readers. Importantly, QFA has significantly higher throughput compared with such methods. QFA cultures grow on a solid agar surface and are therefore well aerated during growth without the need for stirring or shaking. QFA throughput is not as high as that of some Synthetic Genetic Array (SGA) screening methods5,6. However, since QFA cultures are heavily diluted before being inoculated onto agar, QFA can capture more complete growth curves, including exponential and saturation phases3. For example, growth curve observations allow culture doubling times to be estimated directly with high precision, as discussed previously1. Here we present a specific QFA protocol applied to thousands of S. cerevisiae cultures which are automatically handled by robots during inoculation, incubation and imaging. Any of these automated steps can be replaced by an equivalent, manual procedure, with an associated reduction in throughput, and we also present a lower throughput manual protocol. The same QFA software tools can be applied to images captured in either workflow. We have extensive experience applying QFA to cultures of the budding yeast S. cerevisiae but we expect that QFA will prove equally useful for examining cultures of the fission yeast S. pombe and bacterial cultures. PMID:22907268

  10. Bestimmung thermischer Eigenschaften der Gesteine des Unteren und Mittleren Buntsandsteins

    NASA Astrophysics Data System (ADS)

    Franz, Claudia; Schulze, Marcellus

    2016-02-01

    For accurate planning of vertical borehole heat exchanger systems, knowledge of thermo-physical ground parameters is critical. This study reports laboratory-measured thermal conductivity and diffusivity values of Mesozoic sandstones (Lower and Middle Buntsandstein) from four wells. The measurements were made on drill core using an optical scanning method. The mean thermal conductivities of the sandstones range between 2.6 ± 0.3 W / (m · K) and 3.1 ± 0.4 W / (m · K) for dry conditions and between 3.6 ± 0.3 W / (m · K) and 4.1 ± 0.6 W / (m · K) after saturation with water. The mean thermal diffusivity values range between (1.6 ± 0.2) · 10- 6 m2 / s for dry and (2.0 ± 0.6) · 10- 6 m2 / s for water-saturated sandstones. Thermal properties are closely related to the petrography and lithostratigraphy of the sandstones. Additionally, three temperature correction methods were applied for the purpose of evaluating the comparative accuracy and the correction schemes with respect to local in-situ conditions. The results show that the temperature corrections proposed by Somerton (Thermal properties on temperature-related behavior of rock/fluid systems, Elsevier, New York, S 257, 1992) and Sass et al. (J Geophys Res, 97:5017-5030, 1992) are most suited for the respective sandstone data set.

  11. Mikrobielle Kurzzeitteste zur Bestimmung der mutagenen Potenz chemischer Substanzen

    NASA Astrophysics Data System (ADS)

    Gericke, Dietmar

    1983-04-01

    During the last 20 years it became much more interesting to test new chemicals as fast as possible for their carcinogenic potency. Therefore new test models were developed. Mutagenicity seems to be one sign for carcinogenicity. Therefore test systems using microorganisms were studied which are influenced by mutagenic substances. These systems are described, first of all the Ames-Test, using revertants of Salmonella typhimurium, secondly the Escherichia coli system deficient of DNA-polymerase A (DNA-Pol A-). The yeast Saccharomyces cerevisiae was introduced some years ago and finally the Neurospora crassa system serves as an additional test to define exactly the localisation of mutations. The tests and their problems are discussed.

  12. Teaching quantitative biology: goals, assessments, and resources

    PubMed Central

    Aikens, Melissa L.; Dolan, Erin L.

    2014-01-01

    More than a decade has passed since the publication of BIO2010, calling for an increased emphasis on quantitative skills in the undergraduate biology curriculum. In that time, relatively few papers have been published that describe educational innovations in quantitative biology or provide evidence of their effects on students. Using a “backward design” framework, we lay out quantitative skill and attitude goals, assessment strategies, and teaching resources to help biologists teach more quantitatively. Collaborations between quantitative biologists and education researchers are necessary to develop a broader and more appropriate suite of assessment tools, and to provide much-needed evidence on how particular teaching strategies affect biology students' quantitative skill development and attitudes toward quantitative work. PMID:25368425

  13. Estimation of quantitative genetic parameters

    PubMed Central

    Thompson, Robin

    2008-01-01

    This paper gives a short review of the development of genetic parameter estimation over the last 40 years. The need to analyse genetic processes in both animal selection experiments and animal breeding improvement programmes motivated the majority of this work. The usage of animal model in conjunction with residual maximum likelihood (REML) techniques for mixed models has revolutionized the methods. These methods to estimate quantitative genetic parameters have recently been advocated for use in evolutionary studies of natural populations. Therefore, it is perhaps timely to discuss the development of REML methods and their application to the analysis of artificial selection experiments and breeding programmes in animals. This should give extra insight into the methods and hopefully lead to synergy between both the areas. PMID:18211869

  14. Quantitative multiplexed quantum dot immunohistochemistry

    SciTech Connect

    Sweeney, E.; Ward, T.H.; Gray, N.; Womack, C.; Jayson, G.; Hughes, A.; Dive, C.; Byers, R.

    2008-09-19

    Quantum dots are photostable fluorescent semiconductor nanocrystals possessing wide excitation and bright narrow, symmetrical, emission spectra. These characteristics have engendered considerable interest in their application in multiplex immunohistochemistry for biomarker quantification and co-localisation in clinical samples. Robust quantitation allows biomarker validation, and there is growing need for multiplex staining due to limited quantity of clinical samples. Most reported multiplexed quantum dot staining used sequential methods that are laborious and impractical in a high-throughput setting. Problems associated with sequential multiplex staining have been investigated and a method developed using QDs conjugated to biotinylated primary antibodies, enabling simultaneous multiplex staining with three antibodies. CD34, Cytokeratin 18 and cleaved Caspase 3 were triplexed in tonsillar tissue using an 8 h protocol, each localised to separate cellular compartments. This demonstrates utility of the method for biomarker measurement enabling rapid measurement of multiple co-localised biomarkers on single paraffin tissue sections, of importance for clinical trial studies.

  15. Quantitative evaluation of dermatological antiseptics.

    PubMed

    Leitch, C S; Leitch, A E; Tidman, M J

    2015-12-01

    Topical antiseptics are frequently used in dermatological management, yet evidence for the efficacy of traditional generic formulations is often largely anecdotal. We tested the in vitro bactericidal activity of four commonly used topical antiseptics against Staphylococcus aureus, using a modified version of the European Standard EN 1276, a quantitative suspension test for evaluation of the bactericidal activity of chemical disinfectants and antiseptics. To meet the standard for antiseptic effectiveness of EN 1276, at least a 5 log10 reduction in bacterial count within 5 minutes of exposure is required. While 1% benzalkonium chloride and 6% hydrogen peroxide both achieved a 5 log10 reduction in S. aureus count, neither 2% aqueous eosin nor 1 : 10 000 potassium permanganate showed significant bactericidal activity compared with control at exposure periods of up to 1 h. Aqueous eosin and potassium permanganate may have desirable astringent properties, but these results suggest they lack effective antiseptic activity, at least against S. aureus. PMID:26456933

  16. Quantitative DEM of granular packings

    NASA Astrophysics Data System (ADS)

    Brodu, Nicolas; Dijksman, Joshua; Behringer, Robert

    2014-03-01

    We introduce a new model for simulating granular assemblies. This model explicitely accounts for the cross-influence of multiple contacts on grains. It maintains the surface deformations of the grains induced by the contacts, improving on the classical non-deformable interpenetrable spheres model, for a reasonable computational cost. We show that both multiple contacts and surface deformations are necessary for reproducing quantitatively the 3D force measurements we recently demonstrated. We also show that friction has a dramatic effect on the forces and number of contacts, so it cannot be ignored even for very small values. This work was funded by NASA grant NNX10AU01G, NSF grant DMR12-06351 and ARO grant W911NF-1-11-0110.

  17. Estimation of quantitative genetic parameters.

    PubMed

    Thompson, Robin

    2008-03-22

    This paper gives a short review of the development of genetic parameter estimation over the last 40 years. The need to analyse genetic processes in both animal selection experiments and animal breeding improvement programmes motivated the majority of this work. The usage of animal model in conjunction with residual maximum likelihood (REML) techniques for mixed models has revolutionized the methods. These methods to estimate quantitative genetic parameters have recently been advocated for use in evolutionary studies of natural populations. Therefore, it is perhaps timely to discuss the development of REML methods and their application to the analysis of artificial selection experiments and breeding programmes in animals. This should give extra insight into the methods and hopefully lead to synergy between both the areas. PMID:18211869

  18. Quantitative microdialysis under transient conditions.

    PubMed

    Olson, R J; Justice, J B

    1993-04-15

    A microdialysis method is described which allows for the quantitative determination of extracellular analyte concentration under transient conditions. The method provides the extracellular concentration and the in vivo probe recovery as a function of time. The technique is based on the method for steady-state conditions but differs in the use of a between-group rather than a within-group design. Following cocaine and amphetamine administration, a significantly greater increase in extracellular DA was found than was estimated from the dialysate using conventional microdialysis methods. The discrepancy is due to microdialysis probe recovery decreasing concurrently with the increase observed in extracellular DA following cocaine and amphetamine injections. The method estimates the extracellular concentration independently of any changes in recovery. PMID:8494171

  19. Quantitative analysis of qualitative images

    NASA Astrophysics Data System (ADS)

    Hockney, David; Falco, Charles M.

    2005-03-01

    We show optical evidence that demonstrates artists as early as Jan van Eyck and Robert Campin (c1425) used optical projections as aids for producing their paintings. We also have found optical evidence within works by later artists, including Bermejo (c1475), Lotto (c1525), Caravaggio (c1600), de la Tour (c1650), Chardin (c1750) and Ingres (c1825), demonstrating a continuum in the use of optical projections by artists, along with an evolution in the sophistication of that use. However, even for paintings where we have been able to extract unambiguous, quantitative evidence of the direct use of optical projections for producing certain of the features, this does not mean that paintings are effectively photographs. Because the hand and mind of the artist are intimately involved in the creation process, understanding these complex images requires more than can be obtained from only applying the equations of geometrical optics.

  20. Quantitative patterns in drone wars

    NASA Astrophysics Data System (ADS)

    Garcia-Bernardo, Javier; Dodds, Peter Sheridan; Johnson, Neil F.

    2016-02-01

    Attacks by drones (i.e., unmanned combat air vehicles) continue to generate heated political and ethical debates. Here we examine the quantitative nature of drone attacks, focusing on how their intensity and frequency compare with that of other forms of human conflict. Instead of the power-law distribution found recently for insurgent and terrorist attacks, the severity of attacks is more akin to lognormal and exponential distributions, suggesting that the dynamics underlying drone attacks lie beyond these other forms of human conflict. We find that the pattern in the timing of attacks is consistent with one side having almost complete control, an important if expected result. We show that these novel features can be reproduced and understood using a generative mathematical model in which resource allocation to the dominant side is regulated through a feedback loop.

  1. Recent developments in quantitative proteomics.

    PubMed

    Becker, Christopher H; Bern, Marshall

    2011-06-17

    Proteomics is the study of proteins on a large scale, encompassing the many interests scientists and physicians have in their expression and physical properties. Proteomics continues to be a rapidly expanding field, with a wealth of reports regularly appearing on technology enhancements and scientific studies using these new tools. This review focuses primarily on the quantitative aspect of protein expression and the associated computational machinery for making large-scale identifications of proteins and their post-translational modifications. The primary emphasis is on the combination of liquid chromatography-mass spectrometry (LC-MS) methods and associated tandem mass spectrometry (LC-MS/MS). Tandem mass spectrometry, or MS/MS, involves a second analysis within the instrument after a molecular dissociative event in order to obtain structural information including but not limited to sequence information. This review further focuses primarily on the study of in vitro digested proteins known as bottom-up or shotgun proteomics. A brief discussion of recent instrumental improvements precedes a discussion on affinity enrichment and depletion of proteins, followed by a review of the major approaches (label-free and isotope-labeling) to making protein expression measurements quantitative, especially in the context of profiling large numbers of proteins. Then a discussion follows on the various computational techniques used to identify peptides and proteins from LC-MS/MS data. This review article then includes a short discussion of LC-MS approaches to three-dimensional structure determination and concludes with a section on statistics and data mining for proteomics, including comments on properly powering clinical studies and avoiding over-fitting with large data sets. PMID:20620221

  2. Recent Developments in Quantitative Proteomics

    PubMed Central

    Becker, Christopher H.; Bern, Marshall

    2010-01-01

    Proteomics is the study of proteins on a large scale, encompassing the many interests scientists and physicians have in their expression and physical properties. Proteomics continues to be a rapidly expanding field, with a wealth of reports regularly appearing on technology enhancements and scientific studies using these new tools. This review focuses primarily on the quantitative aspect of protein expression and the associated computational machinery for making large-scale identifications of proteins and their post-translational modifications. The primary emphasis is on the combination of liquid chromatography-mass spectrometry (LC-MS) methods and associated tandem mass spectrometry (LC-MS/MS). Tandem mass spectrometry, or MS/MS, involves a second analysis within the instrument after a molecular dissociative event in order to obtain structural information including but not limited to sequence information. This review further focuses primarily on the study of in vitro digested proteins known as bottom-up or shotgun proteomics. A brief discussion of recent instrumental improvements precedes a discussion on affinity enrichment and depletion of proteins, followed by a review of the major approaches (label-free and isotope-labeling) to making protein expression measurements quantitative, especially in the context of profiling large numbers of proteins. Then a discussion follows on the various computational techniques used to identify peptides and proteins from LC-MS/MS data. This review article then includes a short discussion of LC-MS approaches to three-dimensional structure determination and concludes with a section on statistics and data mining for proteomics, including comments on properly powering clinical studies and avoiding over-fitting with large data sets. PMID:20620221

  3. Evaluation of a rapid von Willebrand factor activity latex immuno assay for monitoring of patients with von Willebrand disease (VWD) receiving DDAVP or VWF replacement therapy.

    PubMed

    Vinayagam, S; Simons, L R; Chowdary, P; Thurlow, P; Brooks, S V; Riddell, A F

    2014-07-01

    Haemostatic management of surgery in patients with von Willebrand disease (VWD) includes DDAVP or von Willebrand factor (VWF)-containing concentrates. Although the recommendations are for monitoring by VWF activity assays, it is quite common for clinicians to use factor VIII due usually to longer turnaround times required for VWF ristocetin cofactor assay (VWF:RCo) measurements. The aim of this study was to evaluate use of the rapid HaemosIL VWF activity (VWF:Act) latex immuno assay (LIA) on an automated coagulometer (ACL TOP(™) 700; Instrumentation Laboratory, Bedford, MA, USA) compared to platelet-based VWF:RCo assays in this setting. One hundred and sixty-seven plasma samples from 42 patients [Type 1 (n = 22), Type 2A (n = 2), Type 2B (n = 3), Type 2M (n = 10), Type 3 (n = 3)] and acquired von Willebrand syndrome (n = 2) with VWD treated with DDAVP or VWF-containing concentrates were included in the study. Method comparison and method bias were evaluated by Bland-Altman analysis (BA) and Passing and Bablok regression modelling respectively. BA of baseline samples (n = 39) showed a mean difference of -3.0 (±1.96 SD -25.2 to +19.4). Post (treatment) samples (n = 120) were separated into two groups. Group 1 contained samples with VWF:RCo levels 10 to ?175 IU dL(-1) (n = 97) and group 2, samples with VWF:RCo levels >175 IU dL(-1) (n = 23). BA of group 1 postsamples showed a mean difference of +3.4 (±1.96 SD -44.6 to +51.5), and the BA of Group 2 samples was -23.9 (±1.96 SD -136.1 to +88.3). In conclusion, use of HaemosIL VWF:Act LIA test on an automated coagulometer is a reproducible and rapid assay that can be used as an alternative test for monitoring VWF replacement therapy, facilitating dose adjustments on a real-time basis. PMID:24758424

  4. [The search for "od." Karl Ludwig Freiheer von Reichenbach (1788-1869) and Karl Wilhelm Mayrhofer (1806-1853), two joined against Justus von Liebig].

    PubMed

    Habacher, M

    1980-05-01

    The author describes the controversy between Justus von Liebig on one side and Reichenbach and Mayrhofer on the other side. It is a controversy about problems of science and medicine which are characteristic for the late 18th and the first half of the 19th century, when Mesmerism and similar ideas of occultic and comparative phenomenona were discussed and often refused as being "not scientific". Justus von Liebig and Karl Ludwig Freiherr von Reichenbach were both chemists, both interested in scientific progress and working in this field. They were friends in the years 1830 to 1848. But later on this friendship ended when Reichenbach--who in the mean time moved to Vienna--became more and more interested in phenomenons seen by sensitive persons concerning effects of light. Although Reichenbach himself was not able to recognize the phenomenons he was sure that other persons had this ability. He had the impression that there is a special force floating through the universe, and this force he called "od". Liebig, who was not able to follow this theory and rejected it has speculation, turned against Reichenbach in 1852-3. So the controversy began and their old friendship came to an end. Reichenbach's theory of the "od", characteristic for the time of the romanticism and leading back to Mesmerism was accepted and supported by the Austrian physician Dr. Karl Wilhelm Mayrhofer who had aroused his interest by describing similar phenomenos some of this patients had. The letters of both men, the chemist and the doctor, which are well preserved (Technical Museum of Vienna) and discussed here, give a good impression of Reichenbach's ideas concerning his theory of the "od" and his philosophical ideas. As Reichenbach tried to find a philosophy corresponding to his theory and as he meant to have found this in the philosophy of Friedrich Eduard Beneke his remarks in those letters give a good information about Beneke's discussion of Reichenbach's theory. Mayrhofer, on the other hand, following Reichenbach's theory of the "od", rejected Beneke's philosophy because he himself joined another philisophy on the basis of the christian religion. However, when Reichenbach's latest book on these problems appeared in 1854, Beneke and Mayrhofer had died shortly before and no further discussion was possible. But Reichenbach's theory, based on the ideas of Mesmerism, and the controversial discussion about new explanations of the phenomenona seen by sensitive persons are characteristic for this time and also for our time as such perceptions are not entirely denied but thought over in a new way. PMID:6156792

  5. Environmental probabilistic quantitative assessment methodologies

    NASA Astrophysics Data System (ADS)

    Crovelli, Robert A.

    1995-10-01

    Probabilistic methodologies developed originally for one area of application may be applicable in another area. Therefore, it is extremely important to communicate across disciplines. Of course, a physical reinterpretation is necessary and perhaps some modification of the methodology. This seems to be the situation in applying resource assessment methodologies as environmental assessment methodologies. In this paper, four petroleum resource assessment methodologies are presented as possible pollution assessment methodologies, even though petroleum as a resource is desirable, whereas pollution is undesirable. It is ironic that oil as a precious resource in the ground can become a serious pollutant as a spill in the ocean. There are similarities in both situations where the quantity of undiscovered crude oil and natural gas resources, and the quantity of a pollutant or contaminant are to be estimated. Obviously, we are interested in making a quantitative assessment in order to answer the question, "How much material is there?" For situations in which there are a lack of statistical data, risk analysis is used rather than classical statistical analysis. That is, a relatively subjective evaluation is made rather than an evaluation based on random sampling which may be impossible. Hence, probabilistic quantitative assessment methodologies are needed for the risk analysis. A methodology is defined in this paper to consist of a probability model and a probabilistic method, where the method is used to solve the model. The following four basic types of probability models are considered: (1) direct assessment, (2) accumulation size, (3) volumetric yield, and (4) reservoir engineering. Three of the four petroleum resource assessment methodologies were written as microcomputer systems, viz., TRIAGG for direct assessment, APRAS for accumulation size, and FASPU for reservoir engineering. A fourth microcomputer system termed PROBDIST supports the three assessment systems. TRIAGG is the simplest assessment system, and therefore, more general in application. APRAS is more complex, and FASPU is the most complex. TRIAGG and PROBDIST are completely generic, or general probability systems, in that they are not dependent on the physical context, only on the structure. Hence, they would require no modifications for pollution assessment application. APRAS would require some modification, and FASPU even more; however, many of the ideas of both would be applicable. The three assessment systems have different probability models but the same type of probabilistic method. The type of probabilistic method is analytic probability theory instead of Monte Carlo simulation. Among the advantages of the analytic method are its computational speed and flexibility, making it ideal for a microcomputer. All four IBM-PC compatible microcomputer systems are available from the U.S. Geological Survey Books and Open-File Reports Section.

  6. Quantitative approach of speleothems fluorescence

    NASA Astrophysics Data System (ADS)

    Quiers, Marine; Perrette, Yves; Poulenard, Jérôme; Chalmin, Emilie; Revol, Morgane

    2014-05-01

    In this study, we propose a framework to interpret quantitatively the fluorescence of speleothems organic matter (OM) by the way of a bank of water-extracted organic matter. Due to its efficiency to described dissolved organic matter (DOM) characteritics, fluorescence has been used to determined DOM signatures in natural systems, water circulations, OM transfer from soils, OM evolution in soils or recently, DOM changes in engineered treatment systems. Fluorescence has also been used in speleothems studies, mainly as a growth indicator. Only few studies interpret it as an environmental proxy. Indeed, the fluorescence of OM provides information on the type of organic molecules trapped in speleothems and their evolutions. But the most direct information given by fluorescence is the variation of OM quantities. Actually, increase of fluorescence intensity is generally related to an increase in OM quantity but may also be induced by calcite optical effect or qualitative change of OM. However, analytical technics used in water environments cannot be used for speleothem samples. In this study we propose to give a frame to interpret quantitatively the fluorescence signal of speleothems. 3 different samples of stalagmites from french northern Prealps were used. To allow the quantification of the fluorescence signal, we need to measure the fluorescence and the quantity of organic matter on the same sample. OM of speleothems was extracted by an acid digestion method and analysed with a spectrofluorimeter. However, it was not possible to quantify directly the OM, as the extract solvant was a high-concentrated acid. To solve this problem, a calibration using soil extracts was realised. Soils were chosen in order to represent the diversity of OM present in the environment above the caves. Attention was focused on soil and vegetation types, and landuse. Organic material was water extracted from soils and its fluorescence was also measured. Total organic carbon was performed on the same samples. This allow to compare the two fluorescence signals. A range of OM concentrations can be then attributed to the speleothem signal. Fluorescence measurements were also realised on solid samples, using the MUESLI (Muesli Uses Emission Fluorescence for Line scanning and Imaging). Comparison with the two fluorescence signals, will evaluate the adaptability of the concentrations range for solid measurements, generally used. This method offers the possibility to associate a fluorescence signal on solid speleothem, with a non-destructive method, to an environmental range of organic carbon quantities.

  7. Quantitative imaging as cancer biomarker

    NASA Astrophysics Data System (ADS)

    Mankoff, David A.

    2015-03-01

    The ability to assay tumor biologic features and the impact of drugs on tumor biology is fundamental to drug development. Advances in our ability to measure genomics, gene expression, protein expression, and cellular biology have led to a host of new targets for anticancer drug therapy. In translating new drugs into clinical trials and clinical practice, these same assays serve to identify patients most likely to benefit from specific anticancer treatments. As cancer therapy becomes more individualized and targeted, there is an increasing need to characterize tumors and identify therapeutic targets to select therapy most likely to be successful in treating the individual patient's cancer. Thus far assays to identify cancer therapeutic targets or anticancer drug pharmacodynamics have been based upon in vitro assay of tissue or blood samples. Advances in molecular imaging, particularly PET, have led to the ability to perform quantitative non-invasive molecular assays. Imaging has traditionally relied on structural and anatomic features to detect cancer and determine its extent. More recently, imaging has expanded to include the ability to image regional biochemistry and molecular biology, often termed molecular imaging. Molecular imaging can be considered an in vivo assay technique, capable of measuring regional tumor biology without perturbing it. This makes molecular imaging a unique tool for cancer drug development, complementary to traditional assay methods, and a potentially powerful method for guiding targeted therapy in clinical trials and clinical practice. The ability to quantify, in absolute measures, regional in vivo biologic parameters strongly supports the use of molecular imaging as a tool to guide therapy. This review summarizes current and future applications of quantitative molecular imaging as a biomarker for cancer therapy, including the use of imaging to (1) identify patients whose tumors express a specific therapeutic target; (2) determine whether the drug reaches the target; (3) identify an early response to treatment; and (4) predict the impact of therapy on long-term outcomes such as survival. The manuscript reviews basic concepts important in the application of molecular imaging to cancer drug therapy, in general, and will discuss specific examples of studies in humans, and highlight future directions, including ongoing multi-center clinical trials using molecular imaging as a cancer biomarker.

  8. Quantitative relationships in delphinid neocortex

    PubMed Central

    Mortensen, Heidi S.; Pakkenberg, Bente; Dam, Maria; Dietz, Rune; Sonne, Christian; Mikkelsen, Bjarni; Eriksen, Nina

    2014-01-01

    Possessing large brains and complex behavioral patterns, cetaceans are believed to be highly intelligent. Their brains, which are the largest in the Animal Kingdom and have enormous gyrification compared with terrestrial mammals, have long been of scientific interest. Few studies, however, report total number of brain cells in cetaceans, and even fewer have used unbiased counting methods. In this study, using stereological methods, we estimated the total number of cells in the neocortex of the long-finned pilot whale (Globicephala melas) brain. For the first time, we show that a species of dolphin has more neocortical neurons than any mammal studied to date including humans. These cell numbers are compared across various mammals with different brain sizes, and the function of possessing many neurons is discussed. We found that the long-finned pilot whale neocortex has approximately 37.2 × 109 neurons, which is almost twice as many as humans, and 127 × 109 glial cells. Thus, the absolute number of neurons in the human neocortex is not correlated with the superior cognitive abilities of humans (at least compared to cetaceans) as has previously been hypothesized. However, as neuron density in long-finned pilot whales is lower than that in humans, their higher cell number appears to be due to their larger brain. Accordingly, our findings make an important contribution to the ongoing debate over quantitative relationships in the mammalian brain. PMID:25505387

  9. Quantitative bacteriology in adenoid tissue.

    PubMed

    Pillsbury, H C; Kveton, J F; Sasaki, C T; Frazier, W

    1981-01-01

    Over the past several years the indications for adenoidectomy have become increasingly controversial. Attempts to justify the operation in recurrent otitis media by correlating cultures of the nasopharynx with cultures of middle ear fluid have been inconclusive. Using quantitative bacteriologic techniques, we have studied the levels of aerobic and anaerobic bacteria per gram of tissue in adenoids removed from 48 patients. In seven patients, adenoidectomy was performed for nasal obstruction alone, in 17 patients for chronic serous otitis media, and in 24 patients for recurrent suppurative and serous otitis media. Using the criterion that greater than 10(5) organisms/gm of tissue constitutes infection, we found that 83% (20) of patients in the third group had infected adenoids, as opposed to only 15% (4) in the first and second group combined. Adenoid size measured radiographically did not correlate with the presence of infection. Adenoid size measured radiographically did not correlate with the presence of infection. When recurrent suppurative and serous otitis media are unresponsive to medical therapy including antibiotics and decongestants, adenoidectomy should be considered in addition to myringotomy and ventilation tubes. PMID:6791091

  10. Quantitative dynamics of adipose cells.

    PubMed

    Jo, Junghyo; Shreif, Zeina; Periwal, Vipul

    2012-04-01

    Adipose cells are unique in the dynamism of their sizes, a requisite for their main function of storing and releasing lipid. Lipid metabolism is crucial for energy homeostasis. However, the regulation of lipid storage capacity in conditions of energy excess and scarcity is still not clear. It is not technically feasible to monitor every process affecting storage capacity such as recruitment, growth/shrinkage and death of individual adipose cells in real time for a sufficiently long period. However, recent computational approaches have allowed an examination of the detailed dynamics of adipose cells using statistical information in the form of precise measurements of adipose cell-size probability distributions. One interesting finding is that the growth/shrinkage of adipose cells (> 50 μm diameter) under positive/negative energy balance is proportional to the surface area of cells, limiting efficient lipid absorption/release from larger adipose cells. In addition to the physical characteristics of adipose cells, quantitative modeling integrates dynamics of adipose cells, providing the mechanism of cell turnover under normal and drug-treated conditions. Thus, further use of mathematical modeling applied to experimental measurements of adipose cell-size probability distributions in conjunction with physiological measurements of metabolic state may help unravel the intricate network of interactions underlying metabolic syndromes in obesity. PMID:23700516

  11. Nanoliter high throughput quantitative PCR

    PubMed Central

    Morrison, Tom; Hurley, James; Garcia, Javier; Yoder, Karl; Katz, Arrin; Roberts, Douglas; Cho, Jamie; Kanigan, Tanya; Ilyin, Sergey E.; Horowitz, Daniel; Dixon, James M.; Brenan, Colin J.H.

    2006-01-01

    Understanding biological complexity arising from patterns of gene expression requires accurate and precise measurement of RNA levels across large numbers of genes simultaneously. Real time PCR (RT-PCR) in a microtiter plate is the preferred method for quantitative transcriptional analysis but scaling RT-PCR to higher throughputs in this fluidic format is intrinsically limited by cost and logistic considerations. Hybridization microarrays measure the transcription of many thousands of genes simultaneously yet are limited by low sensitivity, dynamic range, accuracy and sample throughput. The hybrid approach described here combines the superior accuracy, precision and dynamic range of RT-PCR with the parallelism of a microarray in an array of 3072 real time, 33 nl polymerase chain reactions (RT-PCRs) the size of a microscope slide. RT-PCR is demonstrated with an accuracy and precision equivalent to the same assay in a 384-well microplate but in a 64-fold smaller reaction volume, a 24-fold higher analytical throughput and a workflow compatible with standard microplate protocols. PMID:17000636

  12. Quantitative relationships in delphinid neocortex.

    PubMed

    Mortensen, Heidi S; Pakkenberg, Bente; Dam, Maria; Dietz, Rune; Sonne, Christian; Mikkelsen, Bjarni; Eriksen, Nina

    2014-01-01

    Possessing large brains and complex behavioral patterns, cetaceans are believed to be highly intelligent. Their brains, which are the largest in the Animal Kingdom and have enormous gyrification compared with terrestrial mammals, have long been of scientific interest. Few studies, however, report total number of brain cells in cetaceans, and even fewer have used unbiased counting methods. In this study, using stereological methods, we estimated the total number of cells in the neocortex of the long-finned pilot whale (Globicephala melas) brain. For the first time, we show that a species of dolphin has more neocortical neurons than any mammal studied to date including humans. These cell numbers are compared across various mammals with different brain sizes, and the function of possessing many neurons is discussed. We found that the long-finned pilot whale neocortex has approximately 37.2 × 10(9) neurons, which is almost twice as many as humans, and 127 × 10(9) glial cells. Thus, the absolute number of neurons in the human neocortex is not correlated with the superior cognitive abilities of humans (at least compared to cetaceans) as has previously been hypothesized. However, as neuron density in long-finned pilot whales is lower than that in humans, their higher cell number appears to be due to their larger brain. Accordingly, our findings make an important contribution to the ongoing debate over quantitative relationships in the mammalian brain. PMID:25505387

  13. A quantitative philology of introspection.

    PubMed

    Diuk, Carlos G; Slezak, D Fernandez; Raskovsky, I; Sigman, M; Cecchi, G A

    2012-01-01

    The cultural evolution of introspective thought has been recognized to undergo a drastic change during the middle of the first millennium BC. This period, known as the "Axial Age," saw the birth of religions and philosophies still alive in modern culture, as well as the transition from orality to literacy-which led to the hypothesis of a link between introspection and literacy. Here we set out to examine the evolution of introspection in the Axial Age, studying the cultural record of the Greco-Roman and Judeo-Christian literary traditions. Using a statistical measure of semantic similarity, we identify a single "arrow of time" in the Old and New Testaments of the Bible, and a more complex non-monotonic dynamics in the Greco-Roman tradition reflecting the rise and fall of the respective societies. A comparable analysis of the twentieth century cultural record shows a steady increase in the incidence of introspective topics, punctuated by abrupt declines during and preceding the First and Second World Wars. Our results show that (a) it is possible to devise a consistent metric to quantify the history of a high-level concept such as introspection, cementing the path for a new quantitative philology and (b) to the extent that it is captured in the cultural record, the increased ability of human thought for self-reflection that the Axial Age brought about is still heavily determined by societal contingencies beyond the orality-literacy nexus. PMID:23015783

  14. A quantitative philology of introspection

    PubMed Central

    Diuk, Carlos G.; Slezak, D. Fernandez; Raskovsky, I.; Sigman, M.; Cecchi, G. A.

    2012-01-01

    The cultural evolution of introspective thought has been recognized to undergo a drastic change during the middle of the first millennium BC. This period, known as the “Axial Age,” saw the birth of religions and philosophies still alive in modern culture, as well as the transition from orality to literacy—which led to the hypothesis of a link between introspection and literacy. Here we set out to examine the evolution of introspection in the Axial Age, studying the cultural record of the Greco-Roman and Judeo-Christian literary traditions. Using a statistical measure of semantic similarity, we identify a single “arrow of time” in the Old and New Testaments of the Bible, and a more complex non-monotonic dynamics in the Greco-Roman tradition reflecting the rise and fall of the respective societies. A comparable analysis of the twentieth century cultural record shows a steady increase in the incidence of introspective topics, punctuated by abrupt declines during and preceding the First and Second World Wars. Our results show that (a) it is possible to devise a consistent metric to quantify the history of a high-level concept such as introspection, cementing the path for a new quantitative philology and (b) to the extent that it is captured in the cultural record, the increased ability of human thought for self-reflection that the Axial Age brought about is still heavily determined by societal contingencies beyond the orality-literacy nexus. PMID:23015783

  15. Identification of a point mutation in type IIB von Willebrand disease illustrating the regulation of von Willebrand factor affinity for the platelet membrane glycoprotein Ib-IX receptor.

    PubMed Central

    Ware, J; Dent, J A; Azuma, H; Sugimoto, M; Kyrle, P A; Yoshioka, A; Ruggeri, Z M

    1991-01-01

    von Willebrand factor (vWF) supports platelet adhesion on thrombogenic surfaces by binding to platelet membrane glycoprotein (GP) Ib in the GP Ib-IX receptor complex. This interaction is physiologically regulated so that it does not occur between circulating vWF and platelets but, rather, only at a site of vascular injury. The abnormal vWF found in type IIB von Willebrand disease, however, has a characteristically increased affinity for GP Ib and binds to circulating platelets. We have analyzed the molecular basis of this abnormality by sequence analysis of a type IIB vWF cDNA and have identified a single amino acid change, Trp550 to Cys550, located in the GP Ib-binding domain of the molecule comprising residues 449-728. Bacterial expression of recombinant fragments corresponding to this vWF domain yielded molecules that, whether containing a normal Trp550 or a mutant Cys550 residue, bound directly to GP Ib in the absence of modulators and with similar affinity. In contrast, mammalian cell expression of the same segment of sequence yielded molecules that, when containing the normal Trp550, did not bind to GP Ib directly but, like native vWF, bound in the presence of ristocetin. However, molecules containing the point mutation (Cys550) behaved like type IIB vWF--namely, bound to GP Ib even without ristocetin modulation and, in the presence of ristocetin, had 10-fold higher affinity than molecules with normal sequence. These results identify a region of vWF that, although not thought to be directly involved in binding to GP Ib, may modulate the interaction through conformational changes. Images PMID:2011604

  16. Functional domains on von Willebrand factor. Recognition of discrete tryptic fragments by monoclonal antibodies that inhibit interaction of von Willebrand factor with platelets and with collagen.

    PubMed Central

    Sixma, J J; Sakariassen, K S; Stel, H V; Houdijk, W P; In der Maur, D W; Hamer, R J; de Groot, P G; van Mourik, J A

    1984-01-01

    We have identified two functional domains on the von Willebrand factor (VWF) moiety of the Factor VIII-von Willebrand factor complex (FVIII-VWF), one interacting with blood platelets, and one interacting with vessel wall collagens, by means of two monoclonal antibodies directed against the VWF molecule, CLB-RAg 35 and CLB-RAg 201. The monoclonal antibody CLB-RAg 35 inhibited virtually all platelet adherence to artery subendothelium and to purified vessel wall collagen type III, at relatively high wall shear rates. CLB-RAg 35 also inhibited the ristocetin-induced platelet aggregation and the binding of FVIII-VWF to the platelet in the presence of ristocetin but did not affect the binding of FVIII-VWF to collagen. The monoclonal antibody CLB-RAg 201 inhibited the binding of FVIII-VWF to purified vessel wall collagen type I and III and all platelet adherence to collagen type III and the platelet adherence to subendothelium that was mediated by FVIII-VWF in plasma. The two functional domains on FVIII-VWF that were recognized by CLB-RAg 35 and CLB-RAg 201 were identified by means of immunoprecipitation studies of trypsin-digested FVIII-VWF. The domains resided on different polypeptide fragments, with a Mr of 48,000 for the collagen binding domain and a Mr of 116,000 for the platelet binding domain. The 116,000-mol wt fragment consisted of subunits of 52,000/56,000 mol wt and 14,000 mol wt after reduction. The 52,000/56,000-mol wt subunits possessed the epitope for CLB-RAg 35. Images PMID:6332119

  17. Hardware-Abbildung eines videobasierten Verfahrens zur echtzeitfähigen Auswertung von Winkelhistogrammen auf eine modulare Coprozessor-Architektur

    NASA Astrophysics Data System (ADS)

    Flatt, H.; Tarnowsky, A.; Blume, H.; Pirsch, P.

    2010-10-01

    Dieser Beitrag behandelt die Abbildung eines videobasierten Verfahrens zur echtzeitfähigen Auswertung von Winkelhistogrammen auf eine modulare Coprozessor-Architektur. Die Architektur besteht aus mehreren dedizierten Recheneinheiten zur parallelen Verarbeitung rechenintensiver Bildverarbeitungsverfahren und ist mit einem RISC-Prozessor verbunden. Eine konfigurierbare Architekturerweiterung um eine Recheneinheit zur Auswertung von Winkelhistogrammen von Objekten ermöglicht in Verbindung mit dem RISC eine echtzeitfähige Klassifikation. Je nach Konfiguration sind für die Architekturerweiterung auf einem Xilinx Virtex-5-FPGA zwischen 3300 und 12 000 Lookup-Tables erforderlich. Bei einer Taktfrequenz von 100 MHz können unabhängig von der Bildauflösung pro Einzelbild in einem 25-Hz-Videodatenstrom bis zu 100 Objekte der Größe 256×256 Pixel analysiert werden. This paper presents the mapping of a video-based approach for real-time evaluation of angular histograms on a modular coprocessor architecture. The architecture comprises several dedicated processing elements for parallel processing of computation-intensive image processing tasks and is coupled with a RISC processor. A configurable architecture extension, especially a processing element for evaluating angular histograms of objects in conjunction with a RISC processor, provides a real-time classification. Depending on the configuration of the architecture extension, 3 300 to 12 000 look-up tables are required for a Xilinx Virtex-5 FPGA implementation. Running at a clock frequency of 100 MHz and independently of the image resolution per frame, 100 objects of size 256×256 pixels are analyzed in a 25 Hz video stream by the architecture.

  18. New Developments in Lung Endothelial Heterogeneity: von Willebrand factor, P-selectin, and the Weibel-Palade Body

    PubMed Central

    Ochoa, Cristhiaan D.; Wu, Songwei; Stevens, Troy

    2010-01-01

    Quiescent pulmonary endothelium establishes an anti-thrombotic, anti-inflammatory surface that promotes blood flow. However, the endothelium rapidly responds to injury and inflammation by promoting thrombosis and enabling the directed transmigration of inflammatory cells, such as neutrophils, into the alveolar airspace. While the endothelial cell signals responsible for establishing a pro-thrombotic surface are distinct from those responsible for recognizing circulating neutrophils, these processes are highly inter-related. Von Willebrand factor stimulated secretion plays an important role in thrombus formation, while P-selectin surface expression plays a key role in neutrophil binding necessary for transmigration. Both von Willebrand factor and P-selectin are located within Weibel-Palade bodies in pulmonary arteries and arterioles, yet Weibel-Palade bodies are absent in capillaries. Despite the absence of the Weibel-Palade bodies, pulmonary capillaries express both von Willebrand factor and P-selectin. The physiological and pathophysiological significance of these observations is unclear. In this review, we address some anatomic and physiologic features that distinguish pulmonary artery, capillary, and vein endothelium. In addition, we review our current understanding regarding the stimulated secretion of von Willebrand factor and P-selectin in pulmonary artery and capillary endothelium. This information is considered in the context of vasculitis and pneumonia, two pathophysiological processes to which the stimulated secretion of von Willebrand factor and P-selectin contribute. PMID:20490980

  19. Nox4 is critical for hypoxia-inducible factor 2-alpha transcriptional activity in von Hippel-Lindau-deficient renal cell carcinoma.

    PubMed

    Maranchie, Jodi K; Zhan, Ye

    2005-10-15

    Inactivation of the von Hippel-Lindau tumor suppressor (VHL) is an early event in >60% of sporadic clear cell renal cell carcinoma (RCC). Loss of VHL E3 ubiquitin ligase function results in accumulation of the alpha-subunit of the hypoxia-inducible heterodimeric transcription factor (HIF-alpha) and transcription of an array of genes including vascular endothelial growth factor, transforming growth factor-alpha, and erythropoietin. Studies have shown that HIF-alpha can be alternatively activated by reactive oxygen species. Nox4 is an NADP(H) oxidase that generates signaling levels of superoxide and is found in greatest abundance in the distal renal tubules. To determine if Nox4 contributes to HIF activity in RCC, we examined the impact of Nox4 expression on HIF-alpha expression and transactivation. We report here that small inhibitory RNA (siRNA) knockdown of Nox4 in 786-0 human renal tumor cells expressing empty vector (PRC) or wild-type VHL (WT) results in 50% decrease in intracellular reactive oxygen species as measured by a fluorescent 2',7'-dichlorofluorescin diacetate assay, and >85% reduction in HIF2-alpha mRNA and protein levels by quantitative reverse transcription-PCR and Western blot analysis. Furthermore, expression of the HIF target genes, vascular endothelial growth factor, transforming growth factor-alpha, and Glut-1 was abrogated by 93%, 74%, and 99%, respectively, after stable transfection with Nox4 siRNA relative to nontargeting siRNA, as determined by quantitative reverse transcription-PCR. Thus, renal Nox4 expression is essential for full HIF2-alpha expression and activity in 786-0 renal tumor cells, even in the absence of functional VHL. We propose the use of Nox4 as a target in the treatment of clear cell RCC. PMID:16230378

  20. Quantitative historical hydrology in Europe

    NASA Astrophysics Data System (ADS)

    Benito, G.; Brázdil, R.; Herget, J.; Machado, M. J.

    2015-08-01

    In recent decades, the quantification of flood hydrological characteristics (peak discharge, hydrograph shape, and runoff volume) from documentary evidence has gained scientific recognition as a method to lengthen flood records of rare and extreme events. This paper describes the methodological evolution of quantitative historical hydrology under the influence of developments in hydraulics and statistics. In the 19th century, discharge calculations based on flood marks were the only source of hydrological data for engineering design, but were later left aside in favour of systematic gauge records and conventional hydrological procedures. In the last two decades, there has been growing scientific and public interest in understanding long-term patterns of rare floods, in maintaining the flood heritage and memory of extremes, and developing methods for deterministic and statistical application to different scientific and engineering problems. A compilation of 46 case studies across Europe with reconstructed discharges demonstrates that (1) in most cases present flood magnitudes are not unusual within the context of the last millennium, although recent floods may exceed past floods in some temperate European rivers (e.g. the Vltava and Po rivers); (2) the frequency of extreme floods has decreased since the 1950s, although some rivers (e.g. the Gardon and Ouse rivers) show a reactivation of rare events over the last two decades. There is a great potential for gaining understanding of individual extreme events based on a combined multiproxy approach (palaeoflood and documentary records) providing high-resolution time flood series and their environmental and climatic changes; and for developing non-systematic and non-stationary statistical models based on relations of past floods with external and internal covariates under natural low-frequency climate variability.

  1. Quantitative historical hydrology in Europe

    NASA Astrophysics Data System (ADS)

    Benito, G.; Brázdil, R.; Herget, J.; Machado, M. J.

    2015-04-01

    In the last decades, the quantification of flood hydrological characteristics (peak discharge, hydrograph shape, and runoff volume) from documentary evidence has gained scientific recognition as a method to lengthen flood records of rare and extreme events. This paper describes the methodological evolution of the quantitative historical hydrology under the influence of developments in hydraulics and statistics. In the 19th century, discharge calculations based on flood marks was the only source of hydrological data for engineering design, but later was left aside on favour of systematic gauge records and conventional hydrological procedures. In the last two decades, there is growing scientific and public interest to understand long-term patterns of rare floods, maintain the flood heritage and memory of extremes, and to develop methods for deterministic and statistical application to different scientific and engineering problems. A compilation of 45 case studies across Europe with reconstructed discharges demonstrates that (1) in most cases present flood magnitudes are not unusual within the context of the last millennium, although recent floods may exceed past floods in some temperate European rivers (e.g. the Vltava and Po rivers), (2) frequency of extreme floods have decreased since the 1950s, although some rivers (e.g. the Gardon and Ouse rivers) show a reactivation of rare events over the last two decades. There is a great potential of gaining understanding of individual extreme events based on a combined multiproxy approach (palaeoflood and documentary records) providing high-resolution time flood series and their environmental and climatic changes; and to develop non-systematic and non-stationary statistical models based on relations of past floods with external and internal covariates under natural low-frequency climate variability.

  2. Quantitative analyses of bifunctional molecules.

    PubMed

    Braun, Patrick D; Wandless, Thomas J

    2004-05-11

    Small molecules can be discovered or engineered to bind tightly to biologically relevant proteins, and these molecules have proven to be powerful tools for both basic research and therapeutic applications. In many cases, detailed biophysical analyses of the intermolecular binding events are essential for improving the activity of the small molecules. These interactions can often be characterized as straightforward bimolecular binding events, and a variety of experimental and analytical techniques have been developed and refined to facilitate these analyses. Several investigators have recently synthesized heterodimeric molecules that are designed to bind simultaneously with two different proteins to form ternary complexes. These heterodimeric molecules often display compelling biological activity; however, they are difficult to characterize. The bimolecular interaction between one protein and the heterodimeric ligand (primary dissociation constant) can be determined by a number of methods. However, the interaction between that protein-ligand complex and the second protein (secondary dissociation constant) is more difficult to measure due to the noncovalent nature of the original protein-ligand complex. Consequently, these heterodimeric compounds are often characterized in terms of their activity, which is an experimentally dependent metric. We have developed a general quantitative mathematical model that can be used to measure both the primary (protein + ligand) and secondary (protein-ligand + protein) dissociation constants for heterodimeric small molecules. These values are largely independent of the experimental technique used and furthermore provide a direct measure of the thermodynamic stability of the ternary complexes that are formed. Fluorescence polarization and this model were used to characterize the heterodimeric molecule, SLFpYEEI, which binds to both FKBP12 and the Fyn SH2 domain, demonstrating that the model is useful for both predictive as well as ex post facto analytical applications. PMID:15122906

  3. Torque and pressure fluctuations in turbulent von Karman swirling flow between two counter-rotating disks. I

    NASA Astrophysics Data System (ADS)

    Burnishev, Yuri; Steinberg, Victor

    2014-05-01

    We report the experimental studies of the statistical and scaling properties of the fully developed turbulent regime in von Karman swirling flow between counter-rotating disks with and without blades using the only global measurements of the spatially averaged torque ? and pressure p fluctuations in water and water-sugar solutions of different viscosities in the same cell geometry. We show that for all fluids under investigation probability distribution functions (PDFs) of the torque fluctuations ??/?rms are Gaussian in both the laminar and turbulent regimes and for the both types of the stirrers. On the contrary, PDFs of the pressure fluctuations change from Gaussian in the laminar regime into the skewed shape with the exponential tails toward low-pressure events for both the entrainment methods. Both the friction coefficient Cf and normalized rms of the pressure fluctuations Cp are independent of Re in the fully developed turbulent regime for all fluids under study and found in a good quantitative agreement with the previous results. We also observe that the internal flow variables such as the normalized torque bar{? }/Vp_{rms} versus the "internal" Reynolds number Rerms = (prms/?)1/2R?/? instead of the global variables Cf, Cp versus Re show sharp transition into the well developed turbulent regime. We find that the scaling exponents of the fundamental characteristics based only on ? and p measurements in the range of fully developed turbulent flow, namely, the integral, Taylor, and Kolmogorov dissipation lengths, as well as the Taylor-based Reynolds number R?, are in rather fair agreement with the predictions. We would like to emphasize that scaling of the main turbulent parameters R?, ?, ?d obtained via the global variables is a very non-trivial result. It is not obvious that measurements based on the global quantities will provide the predicted scaling relations. The result on such scaling obtained previously strongly disagrees with the scaling predictions. Indeed, both bar{? } and prms are averaged over the cell volume as well as all spatial scales, whereas the swirling flow is neither isotropic nor homogeneous. So the global variables being averaged over all spatial scales get contributions from the scales larger and smaller than those from the inertial range of scales. And finally, the normalized characteristic frequencies fp/frot found in both the torque and pressure frequency power spectra in the fully developed turbulent regime have close values, are independent of Re, and associated with either the rotation or oscillation frequency of the main vortex.

  4. Bilateral papillopathy as a presenting sign of pheochromocytoma associated with von Hippel-Lindau disease.

    PubMed

    Shah, Veeral; Zlotcavitch, Leonid; Herro, Angela M; Dubovy, Sander R; Yehoshua, Zohar; Lam, Byron L

    2014-01-01

    A 7-year-old girl presented with decreased vision in both eyes for 1 month. Examination showed visual acuity of 20/50 and 20/60, no afferent pupillary defect, cecocentral scotomas, and bilateral optic disc edema with extensive peripapillary and macular exudates. Magnetic resonance imaging showed multiple cortical and subcortical white matter lesions. Both the laboratory workup and the systemic examination were unrevealing. However, on follow-up, the patient showed episodic elevations of blood pressure as high as 240/160. Further workup revealed elevated urine catecholamines and a right supra-adrenal mass proven to be a pheochromocytoma by histopathologic analysis. The paroxysmal hypertension resolved, and the visual acuity, visual fields, fundus exam, and neuroimaging improved. The patient was lost to follow-up until age 18 when she developed shortness of breath and was found to have multiple pulmonary metastases identified as pheochromocytoma by biopsy. Genetic testing identified a 3p25-26 (c.482 G>A) VHL gene chromosomal mutation consistent with von Hippel-Lindau disease genotype. Multiple peripheral retinal vascular dilations and small retinal capillary hemangioblastomas were also found. This case highlights the importance of recognizing the lability of blood pressure often seen with pheochromocytomas, which may mask the underlying cause of hypertensive papillopathy and retinopathy, a diagnosis of low clinical suspicion in the pediatric population. The case also underscores the importance of thorough systemic workup, including genotyping to detect conditions where pheochromocytoma may be the presenting sign of the disease, such as multiple endocrine neoplasia 2A and 2B, von Hippel-Lindau disease, von Recklinghausen disease, tuberous sclerosis, and Sturge-Weber syndrome. PMID:24707167

  5. Electrophysiological analysis of the role of novelty in the von Restorff effect

    PubMed Central

    Rangel-Gomez, Mauricio; Meeter, Martijn

    2013-01-01

    Items that are distinctive with respect to their context tend to be recalled better than nondistinctive items, a finding known as the von Restorff effect. The goal of this study was to elucidate the role of novelty in this effect. In two experiments, participants performed a dual task in which they had to study words presented visually while to-be ignored sounds were played over earphones. Sounds could be either standard or novel, and words could be presented in standard or novel font. Sounds were presented either simultaneously with the words (Experiment 1) or preceding them (Experiment 2). Electrophysiological correlates of novelty processing, the N2b and P3a ERP components, were recorded while the words were studied. It was seen that cued recall was better for words presented in novel fonts than for words in a standard font (the von Restorff effect). Words presented while novel sounds were played were remembered worse (Experiment 1) or equally well (Experiment 2) than those combined with standard sounds. Words presented in novel fonts elicited enhanced N2b, P3a, P3b, and N400 components; however, none of these components were specifically larger for subsequently recalled novel-font words. A larger N2b was found for recalled than for nonrecalled words, but this effect was not specific for words presented in novel font. We hypothesized that if novelty was beneficial for memory processing, the N2–P3 complex would be more enhanced for novel words that were later recalled than for those not recalled. The data showed otherwise. This suggests that novelty processing, as indexed by the N2–P3 novelty components, is not the main cause of the von Restorff effect. PMID:23531713

  6. 6 Principles for Quantitative Reasoning and Modeling

    ERIC Educational Resources Information Center

    Weber, Eric; Ellis, Amy; Kulow, Torrey; Ozgur, Zekiye

    2014-01-01

    Encouraging students to reason with quantitative relationships can help them develop, understand, and explore mathematical models of real-world phenomena. Through two examples--modeling the motion of a speeding car and the growth of a Jactus plant--this article describes how teachers can use six practical tips to help students develop quantitative…

  7. A Primer on Disseminating Applied Quantitative Research

    ERIC Educational Resources Information Center

    Bell, Bethany A.; DiStefano, Christine; Morgan, Grant B.

    2010-01-01

    Transparency and replication are essential features of scientific inquiry, yet scientific communications of applied quantitative research are often lacking in much-needed procedural information. In an effort to promote researchers dissemination of their quantitative studies in a cohesive, detailed, and informative manner, the authors delineate…

  8. A Primer on Disseminating Applied Quantitative Research

    ERIC Educational Resources Information Center

    Bell, Bethany A.; DiStefano, Christine; Morgan, Grant B.

    2010-01-01

    Transparency and replication are essential features of scientific inquiry, yet scientific communications of applied quantitative research are often lacking in much-needed procedural information. In an effort to promote researchers dissemination of their quantitative studies in a cohesive, detailed, and informative manner, the authors delineate…

  9. Development and Measurement of Preschoolers' Quantitative Knowledge

    ERIC Educational Resources Information Center

    Geary, David C.

    2015-01-01

    The collection of studies in this special issue make an important contribution to our understanding and measurement of the core cognitive and noncognitive factors that influence children's emerging quantitative competencies. The studies also illustrate how the field has matured, from a time when the quantitative competencies of infants and young…

  10. Using Popular Culture to Teach Quantitative Reasoning

    ERIC Educational Resources Information Center

    Hillyard, Cinnamon

    2007-01-01

    Popular culture provides many opportunities to develop quantitative reasoning. This article describes a junior-level, interdisciplinary, quantitative reasoning course that uses examples from movies, cartoons, television, magazine advertisements, and children's literature. Some benefits from and cautions to using popular culture to teach…

  11. Development and Measurement of Preschoolers' Quantitative Knowledge

    ERIC Educational Resources Information Center

    Geary, David C.

    2015-01-01

    The collection of studies in this special issue make an important contribution to our understanding and measurement of the core cognitive and noncognitive factors that influence children's emerging quantitative competencies. The studies also illustrate how the field has matured, from a time when the quantitative competencies of infants and young…

  12. QUANTITATIVE TRAIT LOCUS ANALYSIS AND METABOLIC PATHWAYS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of molecular markers for crop plants has enabled research on the genetic basis of quantitative traits. However, despite more than a decade of these studies, called quantitative trait locus (QTL) analyses, the molecular basis for variation in most agronomic traits is still largely unk...

  13. Applying Knowledge of Quantitative Design and Analysis

    ERIC Educational Resources Information Center

    Baskas, Richard S.

    2011-01-01

    This study compared and contrasted two quantitative scholarly articles in relation to their research designs. Their designs were analyzed by the comparison of research references and research specific vocabulary to describe how various research methods were used. When researching and analyzing quantitative scholarly articles, it is imperative to…

  14. Ferdinand von Mueller's interactions with Charles Darwin and his response to Darwinism.

    PubMed

    Lucas, A M

    2010-01-01

    Although Ferdinand Mueller (later von Mueller), Government Botanist of Victoria, opposed Darwin's theories when "On the origin of species" was published, there has been little detailed study of the nature of Mueller's opposition from 1860, when he received a presentation copy of "Origin," to his death in 1896. Analysis of Mueller's correspondence and publications shows that he remained a theist and misunderstood key aspects of Darwin's theory. However, Mueller did come to accept that natural selection could operate within a species, although never accepting it could produce speciation. Despite these differences he retained a cordial relationship with Darwin. PMID:20480981

  15. Nutzung von FlexRay als zeitgesteuertes automobiles Bussystem im AUTOSAR-Umfeld

    NASA Astrophysics Data System (ADS)

    Reichelt, Stephan; Schmidt, Karsten; Gesele, Frank; Seidler, Nils; Hardt, Wolfram

    Der vorliegende Beitrag diskutiert das Nutzungspotential des deterministischen Bussystems FlexRay im Automobil. Dabei wird sowohl auf das Konzept einer zeitgesteuerten System- und Knotenarchitektur sowie deren mögliche Umsetzung näher eingegangen. In Verbindung mit dem Standard AUTOSAR und geeigneter Betriebssystemunterstützung lässt sich ein deterministisches Zeitverhalten und dadurch eine erhebliche Verbesserung in der Qualität von Fahrwerkregelsystemen erreichen. Ergänzt wird der Artikel um praktische Erfahrungen bei der Anwendung der aktuellen Entwicklungsumgebung.

  16. Vorhersage des Krankheitsverlaufes von leichten kognitiven Beeinträchtigungen durch automatisierte MRT Morphometrie

    NASA Astrophysics Data System (ADS)

    Fritzsche, Klaus H.; Schlindwein, Sarah; Stieltjes, Bram; Essig, Marco; Meinzer, Hans-Peter

    Die leichte kognitive Beeinträchtigung (LKB) gilt als Anzeichen für ein erhöhtes Risiko der Entwicklung einer Alzheimerdemenz. Eine fundierte klinische Prognose für den Krankheitsverlauf kann aber bis dato nicht gegeben werden. Das Ziel dieser Arbeit besteht darin, eine möglichst präzise Vorhersage mittels automatisierter Morphometrie des Hippokampus im MRT-Bild zu treffen. In einer Studie mit 18 Probanden mit LKB wurde eine Prädiktionsgenauigkeit für die Entwicklung einer späteren Demenz von 83.3% erzielt. Eine manuelle Vergleichsmethode erreichte mit 55.6% Trefferquote keine signifikante Vorhersagegenauigkeit. Das automatische Verfahren erfüllt viele wichtige Voraussetzungen für den routinemäßigen klinischen Einsatz mit dem Potential, die klinische Vorhersage des Krankheitsverlaufes bei der LKB zu verbessern.

  17. Congenital Type III von Willebrand’s disease unmasked by hypothyroidism in a Shetland sheepdog

    PubMed Central

    Scuderi, Margaret; Bessey, Lauren; Snead, Elisabeth; Burgess, Hilary; Carr, Anthony

    2015-01-01

    A 7-year-old, spayed female Shetland sheepdog had sudden onset of right-sided epistaxis. Diagnostic tests revealed Type III von Willebrand’s disease and primary hypothyroidism leading to an acute hypothyroid crisis and acquired factor VIII (FVIII) deficiency. Levothyroxine therapy normalized the serum thyroxine and FVIII concentrations. The delayed onset of disease and the reversible FVIII deficiency that was corrected with levothyroxine therapy, support a role for hypothyroidism in the pathogenesis of this dog’s sudden bleeding tendency as has been seen with hypothyroidism in humans. PMID:26347307

  18. [Johannes Anton von Mikulicz-Radecki (1850-1905). His contributions to the development of urology].

    PubMed

    Zajaczkowski, T; Zamann, A M

    2010-02-01

    On June 14, 1905, Johann Anton von Mikulicz-Radecki, one of the most famous surgeons of the time, died. He was a disciple of famous Theodor Billroth of Vienna and the teacher of Ferdinand Sauerbruch in Breslau. Mikulicz-Radecki's merits in the field of the history of medicine are based on his achievements in developing the system of antisepsis and asepsis. He also devoted himself to urological surgery, and his name is linked with diseases, operations, and construction of new medical instruments. Mikulicz-Radecki created two surgical schools, one in Cracow and a second one in Breslau, where he worked for over 15 years until his death. PMID:20084361

  19. The influence of Hermann von Helmholtz on Heinrich Hertz's contributions to physics

    NASA Astrophysics Data System (ADS)

    Mulligan, Joseph F.

    1987-08-01

    Heinrich Hertz, the discoverer of radio-frequency electromagnetic radiation, also made important contributions to our knowledge of the photoelectric effect, cathode rays, electromagnetic theory, classical mechanics, and meteorology. In 1878 Hertz enrolled at the University of Berlin to study physics under Professor Hermann von Helmholtz. For the rest of his life he maintained a very close personal and scientific relationship with his mentor. The influence of Helmholtz on Hertz's choice of research topics and on the kind of physicist Hertz became is documented from the writings of these two famous physicists.

  20. A Case of von Hippel–Lindau Disease with Colorectal Adenocarcinoma, Renal Cell Carcinoma and Hemangioblastomas

    PubMed Central

    Heo, Su Jin; Lee, Choong-kun; Hahn, Kyu Yeon; Kim, Gyuri; Hur, Hyuk; Choi, Sung Hoon; Han, Kyung Seok; Cho, Arthur; Jung, Minkyu

    2016-01-01

    von Hippel–Lindau (VHL) disease is an autosomal dominant inherited tumor syndrome associated with mutations of the VHL tumor suppressor gene located on chromosome 3p25. The loss of functional VHL protein contributes to tumorigenesis. This condition is characterized by development of benign and malignant tumors in the central nervous system (CNS) and the internal organs, including kidney, adrenal gland, and pancreas. We herein describe the case of a 74-year-old man carrying the VHL gene mutation who was affected by simultaneous colorectal adenocarcinoma, renal clear cell carcinoma, and hemangioblastomas of CNS. PMID:25715769

  1. An investigation of the 'von Restorff' phenomenon in post-test workload ratings

    NASA Technical Reports Server (NTRS)

    Thornton, D. C.

    1985-01-01

    The von Restorff effect in post-task ratings of task difficulty is examined. Nine subjects performed a hovercraft simulation task which combined elements of skill-based tracking and rule- and knowledge-based process control for five days of one hour sessions. The effects of isolated increases in workload on rating of task performance, and on the number of command errors and river band hits are analyzed. It is observed that the position of the workload increase affects the number of bank hits and command errors. The data reveal that factors not directly related to the task performance influence subjective rating, and post-task ratings of workload are biased.

  2. Von Hippel-Lindau Disease Associated Pulmonary Carcinoid with Cranial Metastasis

    PubMed Central

    Zhang, Chao; Yang, Andrew I.; Vasconcelos, Lucas; Moon, Seog; Yang, Chunzhang; Nesvick, Cody L.; Saidkhodjaeva, Lola; Abdullaev, Ziedulla; Pack, Svetlana D.; Ghosh, Arunima; Chittiboina, Prashant; Heiss, John D.; Zhuang, Zhengping

    2014-01-01

    Context: Carcinoids have rarely been described in von Hippel-Lindau (VHL) disease. Objective: We describe the first reported case of a patient with VHL who developed a pulmonary carcinoid that subsequently metastasized to a pre-existent cranial hemangioblastoma. Results: Histological and immunohistochemical features of the metastatic lesion were similar to the primary carcinoid. Both lesions demonstrated heterozygous VHL gene deletions with fluorescence in situ hybridization analysis. Conclusions: This case provides direct molecular genetic evidence of an association between VHL and carcinoids. PMID:24878057

  3. [Urinary and nephrologic aspects of Von Recklinghausen disease. Two case reports and review of the literature].

    PubMed

    Ameur, A; Touiti, D; Jira, H; el Alami, M; Ouahbi, Y; Abbar, M

    2003-08-01

    Urinary tract involvement in neurofibromatosis type 1 is rare and uncommon entity. The syndrome is transmitted as an autosomal dominant trait and is characterized by cutaneous pigmentation and tumors as neural crest origin. Two cases of kidney involvement by Von rechlinghausen's disease with in one case a consequent hydronephrosis with arterial hypertension and in the second a nephrocalcinos without hyperparathyroidism are present. The literature of urogenital and nephrologic neurofibromatosis is reviewed. The authors suggest that the patient with neurofibromatosis be screened annually with medical history, physical examination, urinalysis and serum chemistry for tumors that affect the urinary particularly in children. PMID:12951702

  4. Phakomatosis pigmentovascularis and Lisch nodules. Relationship between Von Recklinghausen and phakomatosis pigmentovascularis?

    PubMed

    Ruiz Villaverde, R; Viera Ramirez, A; Linares Solano, J; Naranjo Sintes, R; Gutierrez Salmerón, M T

    2003-01-01

    In 1947, Ota described a malformative syndrome associating a vascular component (nevus flammeus) with melanocytic or epidermic nevi, which he named phakomatosis pigmentovascularis (PPV). We will discuss the case of a 10-year-old boy presenting giant nevus flammeus, nevus spillus, asymmetry in the development of both lower limbs, characteristic of PPV, together with interventricular communication and Lisch nodules, representative of Von Recklinghausen's disease. We believe that this case can be classified as PPV type IIb, associated with Lisch nodules and rarely described in Caucasian individuals. PMID:12602970

  5. Diagnosis of von Recklinghausen neurofibromatosis and the Albright syndrome. Two case reports.

    PubMed

    Bachmann Andersen, L; Sørensen, S A

    1988-01-01

    We describe two females who were diagnosed as suffering from the Albright syndrome early in childhood. Both have close relatives with neurofibromatosis; it has been established that one of the two, in fact, has von Recklinghausen neurofibromatosis, while it remains uncertain if the other one also has this disorder. Apart from the pattern of café-au-lait hyperpigmentation, these two patients have several symptoms in common: repeated and spontaneous bone fractures leading to pseudarthrosis, frontal bossing, and kyphoscoliosis. Distinguishing between the two diseases is important for genetic counseling since neurofibromatosis, in contrast to the Albright syndrome, is heritable. PMID:3152533

  6. On the von Staudt-Clausen theorem for q-Euler numbers

    NASA Astrophysics Data System (ADS)

    Kim, T.

    2013-03-01

    The q-Euler numbers and polynomials were recently constructed [T. Kim, "The Modified q-Euler Numbers and Polynomials," Adv. Stud. Contemp. Math., 16, 161-170 (2008)]. These q-Euler numbers and polynomials have interesting properties. In this paper, we prove a theorem of the von Staudt-Clausen type for q-Euler numbers; namely, we prove that the q-Euler numbers are p-adic integers. Finally, we prove Kummer-type congruences for the q-Euler numbers.

  7. Gravity Effects in Diffusive Coarsening of Bubble Lattices: von Neumann's Law

    NASA Technical Reports Server (NTRS)

    Noever, David A.

    2000-01-01

    von Neumann modelled the evolution of two-dimensional soap froths as a purely diffusive phenomenon; the area growth of a given cell was found to depend only on the geometry of the bubble lattice. In the model, hexagons are stable, pentagons shrink and heptagons grow. The simplest equivalent to the area growth law is / approximately t(sub beta). The result depends on assuming (1) an incompressible gas; (2) bubble walls which meet at 120 deg and (3) constant wall thickness and curvature. Each assumption is borne out in experiments except the last one: bubble wall thickness between connecting cells varies in unit gravity because of gravity drainage. The bottom part of the soap membrane is thickened, the top part is thinned, such that gas diffusion across the membrane shows a complex dependence on gravity. As a result, experimental tests of von Neumann's law have been influenced by effects of gravity; fluid behavior along cell borders can give non-uniform wall thicknesses and thus alter the effective area and gas diffusion rates between adjacent bubbles. For area plotted as a function of time, Glazier (J.A. Glazier, S.P. Gross, and I. Stavans, Phys. Rev. A. 36, 306 (1987); J. Stavans, J.A, Glazier, Phys. Rev. Lett. 62, 1318 (1989).) suggest that in some cases their failure to observe von Neumann's predicted growth exponent ((sup beta)theor(sup =1; beta)exp(sup =0.70 + 0.10)) may have been the result of such "fluid drainage onto the lower glass plate". Additional experiments which varied plate spacing gave different beta exponents in a fashion consistent with this suggestion. During preliminary long duration experiments (approximately 100 h) aboard Spacelab-J, a low-gravity test of froth coarsening has examined (1) power law scaling of von Neumann's law (beta values) in the appropriate diffusive limits; (2) new bubble lattice dynamics such as greater fluid wetting behavior on froth membranes in low gravity; and (3) explicit relations for the gravity dependence of the second moment (or disorder parameter) governing the geometric spread in cell-sidedness around the mean of perfect hexagonal filling. By reducing the gravity-induced distortion in lattice wall thickness, the diffusion-limited regime of bubble coarsening becomes available for performing critical tests of network dynamics.

  8. An acutely painful elbow as a first presentation of von Willebrand's disease.

    PubMed Central

    Poncia, H D; Ryan, J

    1999-01-01

    A 26 year old woman presented to the accident and emergency department with a painful right elbow. There had been no history of trauma. Clinical examination suggested an effusion, which was confirmed on radiological examination. Her elbow was aspirated and revealed a haemarthrosis. Subsequent investigations revealed a diagnosis of von Willebrand's disease (vWD). A spontaneously occurring effusion of the elbow may be due to a haemarthrosis. Aspiration of blood in the absence of trauma may lead to a diagnosis of an occult coagulopathy in addition to relieving pain. The diagnosis and treatment of vWD is discussed. Images Figure 1 PMID:10191460

  9. Modulare LDAP-Server-, -Protokoll und - Funktionserweiterungen am Beispiel von OpenLDAP

    NASA Astrophysics Data System (ADS)

    Pluta, Daniel

    In diesem Artikel wird ein Standardisierungsvorschlag für eine LDAP-Protokollerweiterung und deren Referenzimplementierung in Form einer modularen Erweiterung für die LDAP-Software-Suite des OpenLDAPProjektes vorgestellt. Nach einer Einführung in und einem Überblick über die wichtigsten OpenLDAP-Komponenten stellen wir unseren Lösungsansatz vor und gehen auf seine technischen Details ein. Ziel dieses Overlays ist die Implementierung einer neuen Funktionalität, die vom LDAP-Protokoll bisher nicht vorgesehen ist: Der Umfang der Suchergebnismenge soll serverseitig, dezentral und in der Granularität ganzer Objekte in Abhängigkeit von der aktuellen Serverzeit (konfigurierbar) eingeschränkt werden.

  10. A Pitfall in the Diagnosis of Unresectable Liver Metastases: Multiple Bile Duct Hamartomas (von Meyenburg Complexes)

    PubMed Central

    Fuks, David; Le Mouel, Jean-Philippe; Chatelain, Denis; Sabbagh, Charles; Demuynck, Fabien; Brevet, Marie; Brehant, Olivier; Nguyen-Khac, Eric; Yzet, Thierry; Dumont, Frederic; Verhaeghe, Pierre; Regimbeau, Jean-Marc

    2009-01-01

    Von Meyenburg complexes (VMC) are a cluster of benign liver malformations including biliary cystic lesions, with congenital fibrocollagenous stroma. This rare entity can mimick multiple secondary hepatic lesions. We report a case of a 56-year-old woman who had multiples liver lesions 12 years after operation for breast cancer. Biopsy of the hepatic lesion confirmed the diagnosis of VMC. Preoperative discovery of multiple gray-white nodular lesions scattered on the surface of the liver should not always contraindicate curative liver resection. The diagnosis of VMC should be known and confirmed with liver biopsy. PMID:21103275

  11. A Pitfall in the Diagnosis of Unresectable Liver Metastases: Multiple Bile Duct Hamartomas (von Meyenburg Complexes).

    PubMed

    Fuks, David; Le Mouel, Jean-Philippe; Chatelain, Denis; Sabbagh, Charles; Demuynck, Fabien; Brevet, Marie; Brehant, Olivier; Nguyen-Khac, Eric; Yzet, Thierry; Dumont, Frederic; Verhaeghe, Pierre; Regimbeau, Jean-Marc

    2009-01-01

    Von Meyenburg complexes (VMC) are a cluster of benign liver malformations including biliary cystic lesions, with congenital fibrocollagenous stroma. This rare entity can mimick multiple secondary hepatic lesions. We report a case of a 56-year-old woman who had multiples liver lesions 12 years after operation for breast cancer. Biopsy of the hepatic lesion confirmed the diagnosis of VMC. Preoperative discovery of multiple gray-white nodular lesions scattered on the surface of the liver should not always contraindicate curative liver resection. The diagnosis of VMC should be known and confirmed with liver biopsy. PMID:21103275

  12. Application of stochastic Liouville-von Neumann equation to electronic energy transfer in FMO complex

    NASA Astrophysics Data System (ADS)

    Imai, Hajime; Ohtsuki, Yukiyoshi; Kono, Hirohiko

    2015-01-01

    A stochastic Liouville-von Neumann approach to solving a spin-boson model is applied to electronic energy transfer in Fenna-Matthews-Olson (FMO) complexes as a case study of the dynamics in biological systems. We modify a noise generation method to treat an experimentally obtained highly structured spectral density. By considering the population dynamics in a two-site system with a model structured spectral density, we numerically observe two kinds of coherent motions associated with inter-site coupling and system-bath coupling, the latter of which is mainly attributed to the peak structure of the spectral density.

  13. Echtzeit- und Regelungstechnische Aspekte bei der automatischen Transformation von Matlab/Simulink in SPS-basierten Steuerungscode

    NASA Astrophysics Data System (ADS)

    Bayrak, G.; Wannagat, A.; Vogel-Heuser, B.

    Die manuelle übertragung von Modellen aus Werkzeugen der Reglungstechnik und in Werkzeuge der Automatisierungstechnik ist fehleranfällig und zeitraubend. In diesem Beitrag wird ein Codegenerator vorgestellt, welcher automatisch nahezu beliebige Modelle aus Matlab/Simulink direkt in ein ablauffähiges Steuerungsprogramm nach IEC 61131-3 transformiert. Die ursprüngliche graphische modulare Struktur von Simulink bleibt auch in der Zielumgebung durch die Verwendung des Continuous Function Chart (CFC), welcher von nahezu allen namhaften Herstellern unterstützt wird, erhalten. Die Ähnlichkeit der Abbildung erleichtert es, den generierten Code zu verifizieren und zu warten. Bisher konnte an einigen Beispielapplikationen, unter anderem eine Pitchregelung einer Windkraftanlage, das exakt gleiche zeitliche Verhalten des generierten Codes im Vergleich zum Simulink-Modell nachgewiesen werden.

  14. Smooth attractors of finite dimension for von Karman evolutions with nonlinear frictional damping localized in a boundary layer

    NASA Astrophysics Data System (ADS)

    Geredeli, Pelin G.; Lasiecka, Irena; Webster, Justin T.

    In this paper dynamic von Karman equations with localized interior damping supported in a boundary collar are considered. Hadamard well-posedness for von Karman plates with various types of nonlinear damping are well known, and the long-time behavior of nonlinear plates has been a topic of recent interest. Since the von Karman plate system is of "hyperbolic type" with critical nonlinearity (noncompact with respect to the phase space), this latter topic is particularly challenging in the case of geometrically constrained, nonlinear damping. In this paper we first show the existence of a compact global attractor for finite energy solutions, and we then prove that the attractor is both smooth and finite dimensional. Thus, the hyperbolic-like flow is stabilized asymptotically to a smooth and finite dimensional set.

  15. Third Åland islands conference on von Willebrand disease, 26–28 September 2012: meeting report

    PubMed Central

    BERNTORP, E.; FUCHS, B.; MAKRIS, M.; MONTGOMERY, R.; FLOOD, V.; O’DONNELL, J. S.; FEDERICI, A. B.; LILLICRAP, D.; JAMES, P.; BUDDE, U.; MORFINI, M.; PETRINI, P.; AUSTIN, S.; KANNICHT, C.; JIMÉNEZ-YUSTE, V.; LEE, C.

    2014-01-01

    Summary The first meeting of international specialists in the field of von Willebrand disease (VWD) was held in the Åland islands in 1998 where Erik von Willebrand had first observed a bleeding disorder in some members of a family from Föglö and a summary of the meeting was published in 1999. The second meeting was held in 2010 and a report of the meeting was published in 2012. Topics covered included progress in understanding of VWD over the last 50 years; multimers; classification of VWD; pharmacokinetics and laboratory assays; genetics; treating the paediatric patient; prophylaxis; geriatrics; gene therapy and treatment guidelines. This third meeting held over 3 days covered the structure and function of von Willebrand factor (VWF); type 1 VWD, the most common form of the disease; a lifespan of pharmacokinetics in VWD; detecting inhibitors in VWD patients; and special challenges in understanding and treating the female VWD patient. PMID:23383607

  16. Gesellschaft, Lebensgemeinschaft, Ökosystem - Über die Kongruenz von politischen und ökologischen Theorien der Entwicklung

    NASA Astrophysics Data System (ADS)

    Voigt, Annette

    Im Jahr 1859 veröffentlichte Charles Darwin "On the Origin of Species“. Seine Evolutionstheorie ist das wohl spektakulärste Beispiel einer naturwissenschaftlichen Theorie großer gesellschaftlicher Relevanz. Ihre verschiedenen Facetten wurden in der Öffentlichkeit kontrovers diskutiert, unter anderem auch ihre Anwendung zur Erklärung von Zuständen und Prozessen menschlicher Gesellschaften. Zum Teil wurde die Seiensweise der Natur - scheinbar unabhängig von gesellschaftlichen Interessen - für die Erklärung und Legitimation gesellschaftlicher Zustände oder die Legitimation von politischen Ideologien herangezogen (Sozialdarwinismus). Denn Gesellschaft funktioniere ja so, wie Darwin die Natur erklärt habe: es herrsche z. B. Konkurrenzkampf, Auslese und Arbeitsteilung, Erfolg hätten diejenigen, die sich an die Bedingungen am Besten anpassten.

  17. Logo and Von Neumann Ideas [and] Towards a Humanistic Use of Computers in Education = Hacia una insercion humanista de las computadoras en la educacion.

    ERIC Educational Resources Information Center

    Reggini, Horacio C.

    The first article, "LOGO and von Neumann Ideas," deals with the creation of new procedures based on procedures defined and stored in memory as LOGO lists of lists. This representation, which enables LOGO procedures to construct, modify, and run other LOGO procedures, is compared with basic computer concepts first formulated by John von Neumann.…

  18. Life-threatening bleeding in a patient with mild hemophilia A and heterozygosity for von Willebrand disease Type 2N.

    PubMed

    Allan, John N; Friedman, Kenneth D; DeSancho, Maria T

    2014-12-01

    Hemophilia A and von Willebrand disease (VWD) are distinct bleeding disorders with a spectrum of clinical phenotypes. They are characterized by mutations in either factor VIII (F8) or von Willebrand factor (VWF) genes, respectively. The pattern of inheritance and appropriate laboratory evaluation differentiates these diseases, and treatment strategies for both are different. Here, we report a male patient with hemophilia A and VWD Type 2 Normandy (N) mutations who presented with life-threatening bleeding. We document his medical history, clinical course, management, and diagnostic work up. PMID:25212677

  19. Congenital platelet disorder and type I von Willebrand disease presenting as prolonged bleeding after cleft lip and palate repair.

    PubMed

    Pang, John; Zelken, Jonathan; Dorafshar, Amir H; Strouse, John J; Redett, Richard

    2014-11-01

    Cleft lip and palate can be associated with coagulopathy. Here, we report the first known case of congenital platelet disorder and von Willebrand disease presenting as prolonged bleeding after cleft lip and palate repair. After identifying the underlying pathology, platelet infusions and aminocaproic acid were given to decrease bleeding from a second surgical procedure. Whole exome sequencing identified a von Willebrand factor gene mutation, an adenine to guanine substitution at the c.475A location. A high index of suspicion should be had for coagulopathy in patients with syndromic cleft lip and palate. PMID:24237226

  20. Charakterisierung von Sulfotransferasen im Gastrointestinaltrakt von Mensch und Ratte und Aktivierung von Promutagenen in V79-Zellen, die eine intestinale Form (1B1) des Menschen und der Ratte exprimieren

    NASA Astrophysics Data System (ADS)

    Teubner, Wera

    2001-05-01

    Die Ausstattung der gastrointestinalen Mukosa des Menschen und der Ratte mit Sulfotransferasen wurde mit Hilfe von Immunodetektion und Enzymaktivitätsmessungen untersucht. In Proben aus Colon und Rektum von 39 Personen wurden die Formen h1A1, h1A3 und h1B1 identifiziert, wobei in einer weiteren Probe, die als einzige von einem an Colitis Ulcerosa erkrankten Patienten stammte, keine Sulfotransferasen nachgewiesen werden konnten. Bei der Immunblot-Analyse war das Expressionsmuster der einzelnen Formen in allen Proben ähnlich. In wenigen Proben waren die relativen Signalintensitäten der h1A1 und der h1B1 um die Hälfte erniedrigt. Der Gehalt von SULT an zytosolischem Protein zeigte einen bis zu 8 - 10fachen Unterschied, er betrug jedoch bei zwei Dritteln der Proben zwischen 0,15 und 0,3 (h1A1 und h1A3) bzw. 0,6 und 0,8 Promille (h1B1). Die Variation konnte nicht auf Alter, Geschlecht oder Krankheitsbild der Patienten zurückgeführt werden. Auch der für die allelischen Varianten der h1A1 beschriebene Effekt auf die Enzymaktiviät bzw. Stabilität konnte in der Menge an immunreaktivem Protein nicht in diesem Ausma detektiert werden. Die Allelhäufigkeit von h1A1*R und h1A1*H war gegenüber der gesunden Bevölkerung nicht verändert. In den sieben Proben aus dem Dünndarm (Coecum, viermal Ileum, Jejunum) konnten zusätzlich die Formen h1E1 und h2A1 identifiziert werden. Ein möglicherweise der Form h1C1 entsprechendes Protein wurde im Magen detektiert. Im Vergleich zum Menschen war die Expression in der Ratte stärker auf die Leber konzentriert. Während beim Menschen in allen untersuchten Abschnitten Sulfotransferasen in Mengen detektiert wurden, die in zwei Fällen (h1B1 und h1A3) sogar den Gehalt in der Leber überstiegen, beschränkte sich die Expression in der Ratte auf im Vergleich zur Leber geringe Mengen im Magen und Dickdarm. Nachgewiesen wurden die r1B1, r1A1 sowie eine nicht identifizierte Form von 35kD, bei der es sich vermutlich um die r1C2 handelt. Im Vergleich zur Leber enthielt der Dickdarm der Ratte 20 - 30 % an r1B1 und 3 % an r1A1, während im Dickdarm des Menschen die 3 - 5fache Menge an h1B1 und 25 - 50 % an h1A1 gefunden wurden. Die nicht identifizierte Form verhielt sich wie die r1B1. Die für die Leber der Ratte bekannte geschlechtsabhängige Expression wurde im Gastrointestinaltrakt nicht beobachtet. Die Verteilung der Sulfotransferasen im Colon und Ileum des Menschen wurde immunhistochemisch untersucht; für die Gewebe der Ratte war die Spezifität der zur Verfügung stehenden Antiseren nicht ausreichend. Im Colon traten h1B1-spezifische Färbungen in den differenzierten Enterozyten am oberen Ende der Krypten auf, im Dünndarm wurden die Epithelzellen der Zotten gefärbt. Die Färbung konzentrierte sich auf das Zytoplasma. Eine ähnliche Verteilung zeigte sich für h1A1 und h1A3, auer da zusätzlich eine intensive Färbung der Endothelzellen der Kapillaren in der Submukosa des Ileums auftrat. Im Dickdarm war dies nur bei den Kapillaren in den Lymphfollikeln zu erkennen. Die h2A1 war lediglich im Zytoplasma der Epithelzellen der Zotten des Ileums nachzuweisen, während im Colon keine Farbreaktion auftrat. Durch die Verwendung der rekombinanten Indikatorstämme TA1538-h1A1, -h1A3 und -h1B1 und des Ausgangsstammes Salmonella typhimurium TA1538 im Ames-Test wurde gezeigt, da verschiedene benzylische und allylische Alkohole durch im humanen Colon exprimierte Sulfotransferasen zu Mutagenen aktiviert werden. In den meisten Fällen erwies sich eine der drei Sulfotransferasen als besonders effizient in der Bioaktivierung, während durch die anderen Formen kein oder nur ein schwacher Effekt verursacht wurde. Die Bioaktivierung von Promutagenen durch Sulfotransferasen im Colon mu im Zusammenhang mit der Lokalisation diskutiert werden. Die Zellen im Darm, in denen immunhistochemisch Sulfotransferasen detektiert wurden, haben mit Ausnahme des Endothels je nach Abschnitt eine Lebensdauer von maximal fünf Tagen und machen keine weiteren Zellteilungen mehr durch. Daher sind DNA-Schäden in diesen Zellen ein sehr geringes Risiko für den Organismus. Soweit die reaktiven Metabolite in diesen Zellen gefangen bleiben, kann die Bioaktivierung in diesen Zellen und die Bildung von Addukten als protektiv betrachten werden, da letztere nach wenigen Tagen mit den toten Zellen in das Darmlumen abgegeben werden. Für den Vergleich der Bioaktiverung von Promutagenen durch die Form 1B1 des Menschen und der Ratte wurden aus V79 Lungenfibroblasten des Chinesischen Hamsters abgeleitete Zellinien hergestellt, die je eine der beiden Formen stabil exprimieren. Damit standen 1B1-profiziente Indikatorzellen für den HPRT-Genmutationstest zur Verfügung, und die 1B1-abhängige Bioaktivierung konnte in einem System untersucht werden, die dem eukaryontischen Organismus näher steht als die für die Ames-Tests verwendeten Bakterien. So war z.B. die Sulfotransferase wie im Gewebe im Zytoplasma lokalisiert. Als Modellsubstanzen wurden hierbei die bereits in TA1538-h1B1 mutagen wirkenden benzylischen Alkohole 6-Hydroxymethylbenzo[a]pyren und 4-Hydroxycyclopenta-[def]chrysen getestet. Da die Sensitivität einer Sulfotransferase-exprimierenden V79-Zellinie sowohl durch die Menge an Sulfotransferase als auch durch die Verfügbarkeit des Sulfodonors limitiert sein könnte, wurden die Mutagenitätsexperimente mit V79-r1B1-Zellinien durchgeführt, die sich in ihrer Enzymaktivität um das Zwanzigfache unterschieden: V79-r1B1/A und -/B. Eine starke Erhöhung der Mutantenfrequenz wurde nur in der hoch exprimierenden Zellinie V79-r1B1/A (1019 ± 224 pmol/mg/min) beobachtet, so da eine gravierende Beeinträchtigung der Sensitivität durch einen Mangel an Kosubstrat ausgeschlossen wurde. In der niedriger exprimierenden Zellinie V79-r1B1/B (57 ± 9 pmol/mg/min) war nur mit 6-Hydroxymethylbenzo[a]pyren ein schwacher Anstieg der Mutantenfrequenz zu erkennen, der mit 0,3 µM bei einer in etwa 100fach höheren Konzentration begann als bei V79-r1B1/A. Die zytosolische Fraktion aus V79-r1B1/B-Zellen enthielt in etwa die dreifache Menge an r1B1-Protein wie die aus Colonmucosa der Ratte. Da zumindest für die humane Mukosa gezeigt wurde, da die 1B1 nur im einschichtigen Epithel, nicht aber in allen Zellen der Mukosa exprimiert wird, repräsentiert die zytosolische Fraktion aus der Mukosa nur bedingt die Expression in den Epithelzellen und der Vergleich mit den V79-1B1-Zellen ist grob. Im Gegensatz zu V79-r1B1/B war die Zellinie V79-h1B1, die ebenfalls nur mit Darm und Leber vergleichbare Mengen an h1B1 exprimierte, in der Lage, beide benzylischen Alkohole zu aktivieren. Der Erhöhung der Mutantenfrequenz im Vergleich zur KontrollZellinie war ähnlich wie bei der stark exprimierenden Zellinie V79-r1B1/A, erforderte aber 10fach höhere Konzentrationen. Somit unterscheiden sich Mensch und Ratte nicht nur insgesamt in ihrer Ausstattung des Gastrointestinaltrakts mit Sulfotransferasen, auch bei Betrachtung einer einzelnen Form zeigten sich deutliche Unterschiede in der Aktivierung von zwei Promutagenen. Die Ratte ist daher ein ungeeignetes Modell, um die Rolle von Sulfotransferasen bei tumorinitiierenden Prozessen im Darm zu untersuchen. Dies unterstreicht die Bedeutung von rekombinanten in-vitro-Systemen für die Erfassung des humanen Metabolismus von Fremdstoffen. Insgesamt kennt man nur eine geringe Anzahl von Substanzen, die im Tierexperiment Colontumore erzeugen, und mit Ausnahme der heterozyklischen aromatischen Amine sind diese lediglich von experimenteller Bedeutung. Dies spricht für effiziente Schutzmechanismen der Darmmukosa gegenüber Mutagenen und lät die Frage nach der hohen Inzidenz des Kolorektalkarzinoms offen. Cytosolic fractions of human and rat gastro-intestinal mucosa were electrophoresed, blotted and probed with six antibodies with differing specificities for sulfotransferase (SULT) forms. Using SULTs heterologously expressed in bacteria for comparison of electrophoretic and immunoreactive properties the following SULTs could be identified in the different parts of the human (h) gastro-intestinal tract: h1A1, h1A3 and h1B1 were detected in all parts analyzed (rectum, colon, caecum, ileum, jejunum, stomach), h1E1 and h2A1 only in the small intestine and h1C1 only in stomach. The presence of h2A1 and h1E1 in the small intestine was also confirmed by enzyme activity measurements using radiolabelled dehydroepiandrosterone and b-estradiol as substrates. SULTs were detected in almost all of the samples analyzed (rectum: 8 of 8, colon: 22 of 23, ileum 5 of 5 and one each of coecum, jejunum and stomach). The colon sample void of SULT protein was the only one taken from a patient suffering from ulcerative colitis. Using an antibody which crossreacts with all human SULT1 forms, a similar pattern of immunoreactivity was observed for all positive samples of rectum and colon mucosa. However, the total amount of immunoreactive protein varied 8 - 10 fold. SULT content in two thirds of the samples was between 0.15 and 0.3 ‰ (h1A1 and h1A3) and 0.6 and 0.8 ‰ (h1B1). This variation could neither be related to age, gender nor disease. The distribution of the allelic variants h1A1*Arg and h1A1*His was analyzed by restriction fragment length polymorphism and the allele frequency in patients suffering from colorectal carcinoma (n = 39) was found not to differ from the values published for normal population. The reduced enzyme activity and stability that has been described for h1A 1*His in platelats was not reflected in the amount of h1A1 protein in the samples of colon and rectum mucosa. Expression of h1A1 and h1A3 was approximately four times higher in ileum than in colon, whereas amounts of h1B1 were comparable in both parts of the intestine. Some of these forms were also expressed at similar, or higher levels in the liver. However, the level of h1B1 protein was higher in the gut than in the liver, and h1A3 was hardly expressed in liver. In rat (r), unlike human, SULTs were poorly expressed in the intestine. r1B1 and an unidentified immunoreactive protein of 35kD were found in the large intestine (rectum, colon, coecum), the proximal jejunum and glandular stomach. r1A1 protein was detected in the large intestine and forestomach. However, the highest levels of these forms in the intestine reached only 3% (r1A1) and 20% (r1B1 and 35kD-protein) of those detected in liver. Unlike in liver, SULT expression in the intestine was independent on gender. Immunohistochemical analysis of human colon and ileum using antibodies specific for either h1B1, h2A1 or all forms of h1A showed that all forms were expressed in the cytosol of the short-lived absorptive cells. In ileum, expression was restricted to villus cells with no staining of crypt cells; except for h1A forms, which were also detected in the endothelial cells of capillaries in the submucosa. In colon, h1B1 and h1A forms, but not h2A1 were detected in the upper third of the crypts. Sensitivities of the antibodies were insufficient for analysis of rat intestine. As 1B1 was the most prominent form in the intestine of both species, Ames tests and hprt gene mutation assays were performed using indicator cells constructed for heterologous expression of 1B1. 6-Hydroxymethylbenzo[a]pyrene and 4-hydroxycyclo-penta[def]chrysene were detected as strong mutagens in Salmonella typhimurium TA1538-h1B1 but neither in the SULT-deficient parental strain nor in bacteria expressing h1A1 or h1A3. Other benzylic or allylic alcohols were mutagenic in Salmonella typhimurium TA1538-h1A1 or h1A3, but not in the h1B1-expressing strain. For the mammalian system, one cell line with high 1B1 activity as determined by turnover of a-naphthol at 1µM and two cell lines with lower activity were established: V79-r1B1/A (1019 ± 224 pmol/mg/min), V79-r1B1/B (57 ± 9 pmol/mg/min) and V79-h1B1 (19 ± 5 pmol/mg/min). 1B1 expression in cytosolic fractions was comparable to rat liver and human colon for V79-r1B1/B and V79-h1B1 respectively. Subcellular distribution was analyzed by immunostaining of cultured cells fixed with methanol. Strong staining of the cytosol was observed in most, but not all of the V79-r1B1/A cells. No staining was observed in V79-r1B1/B, V79-h1B1 or the parental V79 cells. In all cell lines, expression was stable over at least 25 passages and could be detected after 24, 48 and 72 h of cultivation. Population doubling times were 13,1 ± 0.6 h for V79-h1B1 (n = 4), 14.1 ± 1.3 h for V79-r1B1/A (n = 6) and 14.1 ± 1.7 h (n = 3) for V79-r1B1/B. 6-Hydroxymethylbenzo[a]pyrene and 4-hydroxycyclopenta[def]chrysene were detected as strong mutagens in V79-1B1 cells, but not in SULT-deficient control cells. The effect was strong in V79-r1B1/A and V79-h1B1, but weak and occurring at higher concentrations in V79-r1B1/B. Comparing immunoreactivity in cytosolic fractions and fixed cells, h1B1 was expressed more strongly in colonic epithelial cells than in V79-h1B1. It is therefore probable that the compounds tested are also activated in the human gut; however, due to the cellular localization of the enzyme, differentiated cells may be affected primarily. Since these cells are discarded into the gut lumen after a few days and do not undergo further cell divisions, the risk of causing mutations should be low. This mechanism may lead to a presystemic elimination of dangerous compounds. For the study of SULT1B1 mediated mutagenicity in human intestine, rat is a poor model since rat 1B1 was much less capable of activating the benzylic alcohols and was also found to be present in this organ in lower amounts than the human form.