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German
(1994)
Germanistische Linguistik
(1994)
Schreiben : Rechtschreiben
(1994)
Throughfall measurements were made under primary terra firme rainforest in the Rio Pichis valley, in the Upper Amazon Basin of Peru. Based on 214 precipitation events over nearly 18 months, throughfall was estimated to be 83.1±8.8% of gross precipitation. Regression analysis of all events revealed that gross precipitation is the only significant explanatory variable; the use of one-burst events does not significantly improve the regression relationship. Gross precipitation is, however, a poor predictor of throughfall for small rainfall events. The two forest structure parameters, canopy capacity, S, and free throughfall coefficient, p, were determined to be 1.3±0.2 mm and 0.32±0.18 mm. Rainfall intensity was found to influence these parameters. New methods which attempt to minimize the influence of meteorologic variables are used to estimate the potential values of these canopy parameters.
Solubilization by polysoaps
(1994)
The aqueous solubilization power of several series of micellar homopolymers and copolymers (polysoaps) is investigated. Using five insoluble or poorly water-soluble dyes, comparisons of the capacities are made with respect ot the influence of structural variables such as the polymer backbone, the polymer geometry, the comonomer content, and the charge of the hydrophilic group. Some guidelines for polysoap structures suited for efficient solubilization are established. Noteworthy is that the solubilization capacities of the polysoaps are neither linked to the ability to reduce the surface tension of water, nor to the polarity of the solubilization sites deduced from spectroscopic probes.
Die ehemalige Brandenburg auf der Brandenburger Dominsel, der alte Fürstensitz der slawischen Heveller, gab der Mark Brandenburg ihren Namen. 1150 konnte der Markgraf der sächsischen Nordmark, Albrecht der Bär aus dem Geschlecht der am Ostharz begüterten Askanier, die Havelfeste nach dem Tod des letzten Hevellerherrschers besetzen. Zu den bis heute ungeklärten Problemen im Zusammenhang mit der Entstehung der Mark Brandenburg gehört die Frage, wann Albrecht die Burg wieder verlor, so daß er gezwungen war, sie durch eine Belagerung zum zweiten Male in seine Gewalt zu bringen, was am 11. Juni 1157 geschah. In der folgenden Untersuchung soll erneut der Frage nachgegangen werden, zu welchem Zeitpunkt dem Markgrafen die Brandenburg noch einmal entrissen worden war.
Sinnkrise des Wissens
(1994)
Cognitive acceleration
(1994)
In this paper, we show that symplectic partitioned Runge-Kutta methods conserve momentum maps corresponding to linear symmetry groups acting on the phase space of Hamiltonian differential equations by extended point transformation. We also generalize this result to constrained systems and show how this conservation property relates to the symplectic integration of Lie-Poisson systems on certain submanifolds of the general matrix group GL(n).
Inhalt: 1. Vorbemerkungen 2. Zu einigen philosophischen und theoretisch-linguistischen Grundlagen einer kommunikativ orientierten Betrachtung der Sprache 3. Sprache und menschliche Gesellschaft 4. Der Euphemismus 5. Euphemismen im Golfkrieg - Zur Analyse der Untersuchungsergebnisse 6. Zusammenfassung und Schlußfolgerungen 7. Perspektiven der kommunikativen Sprachforschung bezüglich 215der Untersuchung des politischen Euphemismus - Forschungsausblick und Schlußbemerkungen
In cultured rat hepatocytes the key gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PCK) is known to be induced by glucagon via an elevation of cAMP. Prostaglandin E₂ has been shown to antagonize the glucagon-activated cAMP formation, glycogen phosphorylase activity and glucose output in hepatocytes. It was the purpose of the current investigation to study the potential of PGE₂ to inhibit the glucagon-induced expression of PCK on the level of mRNA and enzyme activity. PCK mRNA and enzyme activity were increased by 0.1 nM glucagon to a maximum after 2 h and 4 h, respectively. This increase was completely inhibited if 10 μM PGE2 was added concomitantly with glucagon. This inhibition by PGE₂ of glucagon-induced PCK activity was abolished by pertussis toxin treatment. When added at the maximum of PCK mRNA at 2 h, PGE₂ accelerated the decay of mRNA and reduced enzyme activity. This effect was not reversed by pertussis toxin treatment. Since in liver PGE₂ is derived from Kupffer cells, which play a key role in the local inflammatory response, the present data imply that during inflammation PGE₂ may reduce the hepatic gluconeogenic capacity via a Gᵢ-linked signal chain.
Rat hepatocytes have previously been reported to possess prostaglandin E₂ receptors of the EP₃-type (EP₃-receptors) that inhibit glucagonstimulated glycogenolysis by decreasing cAMP. Here, the isolation of a functional EP₃ϐ receptor cDNA clone from a rat hepatocyte cDNA library is reported. This clone can be translated into a 362-amino-acid protein, that displays over 95% homology to the EP₃ϐ receptor from mouse mastocytoma. The amino- and carboxy-terminal region of the protein are least conserved. Transiently transfected HEK 293 cells expressed a single binding site for PGE₂ with an apparent Kd of 15 nM. PGE₂ > PGF₂α > PGD₂ competed for [³H]PGE₂ binding sites as did the EP₃ receptor agonists M&B 28767 = sulprostone > misoprostol but not the EP₁ receptor antagonist SC 19220. In stably transfected CHO cells M&B 28767 > sulprostone = PGE₂ > misoprostol > PGF₂α inhibited the forskolin-elicited cAMP formation. Thus, the characteristics of the EP₃ϐ receptor of rat hepatocytes closely resemble those of the EP₃ϐ receptor of mouse mastocytoma.
We have studied bifurcation phenomena for the incompressable Navier-Stokes equations in two space dimensions with periodic boundary conditions. Fourier representations of velocity and pressure have been used to transform the original partial differential equations into systems of ordinary differential equations (ODE), to which then numerical methods for the qualitative analysis of systems of ODE have been applied, supplemented by the simulative calculation of solutions for selected initial conditions. Invariant sets, notably steady states, have been traced for varying Reynolds number or strength of the imposed forcing, respectively. A complete bifurcation sequence leading to chaos is described in detail, including the calculation of the Lyapunov exponents that characterize the resulting chaotic branch in the bifurcation diagram.
Linguistics in Potsdam
(1994)
Nasledujúci príspevok poslal časopisu Viera a život vedecký pracovník katolíckej teologickej fakulty na Regensburskej univerzite (Nemecko) pán Stefan Gatzhammer, M. A., Líc. iur. can. Podkladom pre článok bola rozpracovaná vedecká štúdia, preto aj nemecká pôvodina príspevku mala bohaté a dôkladné poznámky. S láskavým súhlasom autora sme pre potreby našich čitateľov poznámky zjednodušili. Pôvodný nemecký titul článku znie: „Die Ausweisung der Jesuiten aus Portugal 1759/60. Der Brasilienmissionar P. Josef Keyling SJ aus Schemnitz." Príspevok do slovenčiny preložila Zuzana Vaňová.
Inhalt: 1. CHARAKTER DER ANLAGE 2. AUFGABENSTELLUNG 3. ZIEL DER ARBEIT 4. ANTIKE QUELLEN 5. FORSCHUNGSGESCHICHTE 6. VERMESSUNG DER ANLAGE (Blatt 1) 7. BESTANDSAUFNAHME (Blatt 2) 8. GRABUNGSARBEITEN 8.1 Die Plana - schichtenweises Abtragen (Blätter 2, 3, 4) 8.2 Anlegen von Schnitten (Blätter 5, 6, 7) 8.3 Zeichnen der Profile (Blätter 8, 9, 10) 8.4 Beschreibung 9. ARCHITEKTURELEMENTE 9.1. Architrave (Blatt 11) 9.2. Säulenfragmente (Blatt 12) 9.3. Hohlkehlen, Steine mit dem Uräusschlangenmotiv und andere Architekturelemente (Blätter 11, 13, 14, 15) 9.4. Fundamentsteine ( Blatt 16) 10. SKULPTUREN (Blätter 17, 18, 19) 11. KLEINFUNDE (Blatt 20) 12. SONSTIGE FUNDE (Blätter 21, 22, 23) 13. KERAMIK 13.1. Vereinfachte Keramikbearbeitung (Blätter 24, 25) 13.2. Verfeinerte Methode der Keramikbearbeitung (Blatt 26) 13.3. Vollständige Keramikgefäße 14. FOTOARBEITEN 15. REKONSTRUKTION
The site of confluence of the artery and the portal vein in the liver still appears to be controversial. Anatomical studies suggested a presinusoidal or an intrasinusoidal confluence in the first, second or even final third of the sinusoids. The objective of this investigation was to study the problem with functional biochemical techniques. Rat livers were perfused through the hepatic artery and simultaneously either in the orthograde direction from the portal vein to the hepatic vein or in the retrograde direction from the hepatic vein to the portal vein. Arterial how was linearly dependent on arterial pressure between 70 cm H2O and 120 cm H2O at a constant portal or hepatovenous pressure of 18 cm H2O. An arterial pressure of 100 cm H2O was required for the maintenance of a homogeneous orthograde perfusion of the whole parenchyma and of a physiologic ratio of arterial to portal how of about 1:3. Glucagon was infused either through the artery or the portal vein and hepatic vein, respectively, to a submaximally effective ''calculated'' sinusoidal concentration after mixing of 0.1 nmol/L. During orthograde perfusions, arterial and portal glucagon caused the same increases in glucose output. Yet during retrograde perfusions, hepatovenous glucagon elicited metabolic alterations equal to those in orthograde perfusions, whereas arterial glucagon effected changes strongly reduced to between 10% and 50%. Arterially infused trypan blue was distributed homogeneously in the parenchyma during orthograde perfusions, whereas it reached clearly smaller areas of parenchyma during retrograde perfusions. Finally, arterially applied acridine orange was taken up by all periportal hepatocytes in the proximal half of the acinus during orthograde perfusions but only by a much smaller portion of periportal cells in the proximal third of the acinus during retrograde perfusions. These findings suggest that in rat liver, the hepatic artery and the portal vein mix before and within the first third of the sinusoids, rather than in the middle or even last third.
Inhalt: 1. Kritische Erläuterung der Bilder und Texte jeder Folge - 1. Folge: Funde der Bronzezeit (Ein Film von Uschi Demitter) - 2. Folge: Germanische Stämme (Ein Film von Uschi Demitter) - 3. Folge: Siedlung der Slawen (Ein Film von Kurt Barthel - 4. Folge: Das verschwundene Heiligtum (Ein Film von Kurt Barthel) - 5. Folge: Von der Kaiserpfalz zur Stadt (Ein Film von Uschi Demitter und Richard Krause) 2. Einordnung der historischen Details der Folgen in den Geschichtsprozeß - 1. Folge: Funde der Bronzezeit - 2. Folge: Germanische Stämme - 3. Folge: Siedlung der Slawen - 4. Folge: Das verschwundene Heiligtum - 5. Folge: Von der Kaiserpfalz zur Stadt 3. Didaktisch-methodische Empfehlungen zum Einsatz der Sendereihe 3.1 Zuordnung der Sendefolgen zu den Rahmenplänen 3.2 Hinweise für die Unterrichtsarbeit des Lehrers 4. Ergänzende Medien zu den Themenbereichen in der Sammlung des MPZ
Earlier investigations at South Creek in northeastern Queensland established the importance of overland flow as a hydrologic pathway in this tropical rainforest environment. Since this pathway is ‘fast’, transmitting presumably ‘new’ water, its importance should be reflected in the stormflow chemistry of South Creek: the greater the volumentric contribution to the stormflow hydrograph, the more similarity between the chemical composition of streamwater and of overland flow is to be expected. Water samples were taken during two storm events in an ephemeral gully (gully A), an intermittent gully (gully B) and at the South Creek catchment outlet; additional spot checks were made in several poorly defined rills. The chemical composition of ‘old’ water was determined from 45 baseflow samples collected throughout February. The two events differed considerably in their magnitudes, intensities and antecedent moisture conditions. In both events, the stormflow chemistry in South Creek was characterized by a sharp decrease in Ca, Mg, Na, Si, Cl, EC, ANC, alkalinity and total inorganic carbon. pH remained nearly constant with discharge, whereas K increased sharply, as did sulfate in an ill-defined manner. In event 1, this South Creek stormflow pattern was closely matched by the pattern in gully A, implying a dominant contribution of ‘new’ water. This match was confirmed by the spot samples from rills. Gully B behaved like South Creek itself, but with a dampened ‘new’ water signal, indicating less overland flow generation in its subcatchment. In event 2, which occurred five days later, the initial ‘new’ water signal in gully A was rapidly overwhelmed by a different signal which is attributed to rapid drainage from a perched water table. This study shows that stormflow in this rainforest catchment consists predominantly of ‘new’ water which reaches the stream channel via ‘fast’ pathways. Where the ephemeral gullies delivering overland flow are incised deeply enough to intersect a perched water table, a delayed, ‘old’ water-like signal may be transmitted.