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Fast analysis of different species of molecules in soils is investigated by capillary electrophoresis (CE). Several CE techniques for the analysis of inorganic ions and carbohydrates have been tested. With regard to the intents of pedologists and the usually large number of soil analyses a bundle of CE systems is proposed, capable of effecting time-saving soil analyses. Adapted electrolyte systems recently published and new separation systems are described. Examples of the application of these methods to two different soil samples are presented.
Chemical fingerprints of hydrological compartments and flow paths at La Cuenca, western Amazonia
(1995)
A forested first-order catchment in western Amazonia was monitored for 2 years to determine the chemical fingerprints of precipitation, throughfall, overland flow, pipe flow, soil water, groundwater, and streamflow. We used five tracers (hydrogen, calcium, magnesium, potassium, and silica) to distinguish “fast” flow paths mainly influenced by the biological subsystem from “slow” flow paths in the geochemical subsystem. The former comprise throughfall, overland flow, and pipe flow and are characterized by a high potassium/silica ratio; the latter are represented by soil water and groundwater, which have a low potassium/silica ratio. Soil water and groundwater differ with respect to calcium and magnesium. The groundwater-controlled streamflow chemistry is strongly modified by contributions from fast flow paths during precipitation events. The high potassium/silica ratio of these flow paths suggests that the storm flow response at La Cuenca is dominated by event water.
Previous hydrometric studies demonstrated the prevalence of overland flow as a hydrological pathway in the tropical rain forest catchment of South Creek, northeast Queensland. The purpose of this study was to consider this information in a mixing analysis with the aim of identifying sources of, and of estimating their contribution to, storm flow during two events in February 1993. K and acid-neutralizing capacity (ANC) were used as tracers because they provided the best separation of the potential sources, saturation overland flow, soil water from depths of 0.3, 0.6, and 1.2 m, and hillslope groundwater in a two-dimensional mixing plot. It was necessary to distinguish between saturation overland flow, generated at the soil surface and following unchanneled pathways, and overland flow in incised pathways. This latter type of overland flow was a mixture of saturation overland flow (event water) with high concentrations of K and a low ANC, soil water (preevent water) with low concentrations of K and a low ANC, and groundwater (preevent water) with low concentrations of K and a high ANC. The same sources explained the streamwater chemistry during the two events with strongly differing rainfall and antecedent moisture conditions. The contribution of saturation overland flow dominated the storm flow during the first, high-intensity, 178-mm event, while the contribution of soil water reached 50% during peak flow of the second, low-intensity, 44-mm event 5 days later. This latter result is remarkably similar to soil water contributions to storm flow in mountainous forested catchments of the southeastern United States. In terms of event and preevent water the storm flow hydrograph of the high-intensity event is dominated by event water and that of the low-intensity event by preevent water. This study highlights the problems of applying mixing analyses to overland flow-dominated catchments and soil environments with a poorly developed vertical chemical zonation and emphasizes the need for independent hydrometric information for a complete characterization of watershed hydrology and chemistry.
We consider the numerical treatment of Hamiltonian systems that contain a potential which grows large when the system deviates from the equilibrium value of the potential. Such systems arise, e.g., in molecular dynamics simulations and the spatial discretization of Hamiltonian partial differential equations. Since the presence of highly oscillatory terms in the solutions forces any explicit integrator to use very small step size, the numerical integration of such systems provides a challenging task. It has been suggested before to replace the strong potential by a holonomic constraint that forces the solutions to stay at the equilibrium value of the potential. This approach has, e.g., been successfully applied to the bond stretching in molecular dynamics simulations. In other cases, such as the bond-angle bending, this methods fails due to the introduced rigidity. Here we give a careful analysis of the analytical problem by means of a smoothing operator. This will lead us to the notion of the smoothed dynamics of a highly oscillatory Hamiltonian system. Based on our analysis, we suggest a new constrained formulation that maintains the flexibility of the system while at the same time suppressing the high-frequency components in the solutions and thus allowing for larger time steps. The new constrained formulation is Hamiltonian and can be discretized by the well-known SHAKE method.
Aus dem Inhalt: Die Jahre 1780-1806 gelten als die Epoche der ersten, nunmehr weltbekannten jüdischen Salons von Berlin. Während die amerikanische Forscherin Deborah Hertz insgesamt neun jüdische Salons aufzählt, werden üblicherweise als die drei wichtigsten die folgenden genannt: die der Henriette Herz, Rahel Varnhagen und Dorothea Schlegel. Diese drei Frauen haben - als Frauen und Jüdinnen - die doppelte Leistung des Ausbruchs aus ihrer gesellschaftlichen Stellung vollbracht, der später Emanzipation genannt wurde, zugleich haben sie durch Taufe die Emanzipation überschritten und dadurch die - zumindest äußere - Assimilation vollzogen. Unter Historikern gab es über sie geteilte Meinungen: Den jüdischen waren sie zu wenig, den nicht-jüdischen zu sehr jüdisch gewesen. Wer sich aber mit der deutsch-jüdischen Geschichte der Aufklärung und der Romantik befaßt, kann an ihren kurzen Schöpfungen, den kulturprägenden Salons, kaum vorbei.
Excerpt: Hasidic Ashkenazi literature is known to scholars of Jewish religion as one of the most prolific sources of medieval Jewish magic or magical beliefs. This is all the more astonishing as the non esoteric writings of the Hasidey Ashkenaz represent a rather traditional Jewish piety as known to us from talmudic sources. Considering this duality of an almost traditional Jewish piety on the one hand and very distinct magic tenets on the other, we may ask whether the Hasidey Ashkenaz themselves perceived any difference between magic and religion. There are indeed a number of modern historians of religion who completely deny the validity of such a distinction, for in most historical religions magic and religion are in fact intertwined to a certain degree, thus permitting almost no differentiation between the two.
Reversible changes in the self-organization of polysoaps may be induced by controlling their charge numbers via covalently bound redox moieties. This is illustrated with two viologen polysoaps, which in response to an electrochemical stimulus, change their solubility and aggregation in water, leading from homogeneously dissolved and aggregated molecules to collapsed ones and vice verse. Using the electrochemical quartz crystal microbalance (EQCM), it could be shown that the reversibility of this process is better than 95% in 16 cycles.
A series of amphiphilic copolymers is prepared by copolymerization of choline methacrylate with 1,1,2,2-tetrahydroperfluorooctyl methacrylate in varying amounts. The copolymers bearing fluorocarbon chains are studied concerning their effects on viscosity, solubilization and surface activity in aqueous solution, exhibiting a general behavior characteristic for polysoaps. The results are compared with the ones obtained for an analogous series of amphiphilic copolymers bearing hydrocarbon chains.
Περιεχόμενα: - Εισαγωγή - Αφετηρία 1. Η εκπαιδευτική κατάσταστη στην ΟΔΓ 1.1. Η κατάσταση στο κανονικό γερμανικό σχολείο 1.2 Η κατάσταση διδασκαλίας της μητρικής γλώσσας στην ΟΔΓ 2. Η σχολική κατάσταση στην Ελλάδα μετά την παλιννόστηση 2.1. Η κατάσταση στο κανονικό ελληνικό σχολείο - Σχολικές επιδόσεις - Κοινωνιοψυχολογική κατάσταση 2.2. Η κατάσταση σε ό,τι αφορά την πρόσθετη διδασκαλία για παλιννοστούντες στην Ελλάδα 3. Συμπεράσματα
The existence of the Soviet Union was a remarkable anomalie in the history of the 20th century, which was also characterized by the collapse of multinational and colonial empires. Starting with the structural definitions of empires, the author describes the particularities of the Soviet empire. He analyzes the order, ideology and culture of the Soviet Empire. Looking for the reasons of its collapse, he presents a genesis of the longterm and short-term reasons. He is focusing on the breakdown of the post-totalitarian Leviathan, the cultural decline, the renaissance of nationalism and of the imperial overstretching. Finally he asseses the role of the policy of Perestroika in the breakdown of the Soviet Empire in the beginning of the 1990s.
Based on the discussion on Germany´s new 'central location', the author tries to sketch Germany´s geopolitical position in view of the constellation of powers in Europe from a national point of view. This favourable position offers a great chance for the country to play an active role in Europe’s integration. However, German historical heritage as well as the delicate relationship of Germany´s political elite to the use of power are reasons for the country´s hesitation to fulfill her neighbours’ and her allies’ expectations. Anyhow, Summaries 192 rooted in the West-European and transatlantic integration is Germany the natural dooropener for its Eastern, South-Eastern and Baltic neighbours to become 'members of the club'. )</a> Jahresabo: 40,00 € (ermäßigt: 25,00 €)
The Chinese coastal cities play an increasing economic role in the Yellow Sea region. The inclusion of these cities into the intra Asian economic cooperation is accomplished not only in the conventional sphere of trade but also by a growing involvement in telecommunication networks, technological exchange and the circulation of human resources. That is why these cities emerge as autonomous actors in the East Asian integration process. In this context national states face deep structural change, especially in the field of sovereignty and territory. Concerning the internal situation of China, this change could also cause a turn over of the relationship between the central government and the regions.
The article argues that the concept of statehood is not functioning any longer. It exists a crisis for the international legal order which is represented by the failure of state to maintain order within its borders. The problem of violence in international relations are connected to the implosion of a considerable number of the state entities in the contemporary international society. The federalist institutional approach in international law and international theory could not contribute in an appropriate way to the solution of the "problem of violence", because it supposes a willingness on the part of states to do so. Only the concept of "national interest", in a sociological sense, connected to the development of a discource of solidarity and mutual responsibility between the "West" and the "rest of the world" offers the possibility to create a common consciousness which could make it easier to overcome the contemporary crises for the international legal order.
The failure of politics is closely connected with deeply rooted misconceptions about the term politics. The author argues that a re-reading of Immanuel Kant's work "The Perpetual Peace" written 200 years ago offers a challenging possibility for a new conceptualization of politics, morality and peace. Morality is seen by Kant as an essential dimension of politics and the implementation and acknowledgement of laws by moral demands is defined as a precondition for a community of free citizens. In its public discourse politics does require law and morality. Deriving future rights from existing laws is one of the most favored argumentation used by politicians in the public. If the needs of law and justice are interpretated by politicians in their own interest, i.e. above all guarantees for the realization of political selfdetermination, then a real chance will exist for improving peace in the future.
Prostaglandins, released from Kupffer cells, have been shown to mediate the increase in hepatic glycogenolysis by various stimuli such as zymosan, endotoxin, immune complexes, and anaphylotoxin C3a involving prostaglandin (PG) receptors coupled to phospholipase C via a G(0) protein. PGs also decreased glucagon-stimulated glycogenolysis in hepatocytes by a different signal chain involving PGE(2) receptors coupled to adenylate cyclase via a G(i) protein (EP(3) receptors). The source of the prostaglandins for this latter glucagon-antagonistic action is so far unknown. This study provides evidence that Kupffer cells may be one source: in Kupffer cells, maintained in primary culture for 72 hours, glucagon (0.1 to 10 nmol/ L) increased PGE(2), PGF(2 alpha), and PGD(2) synthesis rapidly and transiently. Maximal prostaglandin concentrations were reached after 5 minutes. Glucagon (1 nmol/L) elevated the cyclic adenosine monophosphate (cAMP) and inositol triphosphate (InsP(3)) levels in Kupffer cells about fivefold and twofold, respectively. The increase in glyco gen phosphorylase activity elicited by 1 nmol/L glucagon was about twice as large in monocultures of hepatocytes than in cocultures of hepatocytes and Kupffer cells with the same hepatocyte density. Treatment of cocultures with 500 mu mol/L acetylsalicylic acid (ASA) to irreversibly inhibit cyclooxygenase (PGH-synthase) 30 minutes before addition of glucagon abolished this difference. These data support the hypothesis that PGs produced by Kupffer cells in response to glucagon might participate in a feedback loop inhibiting glucagon-stimulated glycogenolysis in hepatocytes.
There is sufficient evidence of integration processes in the Asia-Pacific rim. But these processes differ profoundly from the European case. On the other hand integration theory up to the present day has been based mainly on the European evidence. Does this mean, that conventional integration theory is irrelevant in the case of the Asia-Pacific development? This contributuion tries to re-examine the theoretical capacity of various approaches (institionalism, functionalism, regionalism, flying geese pattern, regime-theory) when applied to the realities of transnational interaction and international organization in the Asia-Pacific rim.
The article reviews water-soluble polymers characterized by surfactant side chains, and related amphiphilic polymers. Various synthetic approaches are presented, and rules for useful molecular architectures are given. Models for the self-organization of such polymers in water are presented comparing them with the micellization of low molecular weight surfactants. Highlighting key properties of aqueous polysoap solutions such as viscosity, surface tension and solubilization power, some structure-property relationships are established. Further, the formation of mesophases and of superstructures in bulk is addressed. Finally, the functionalization of polysoaps, and potential applications are discussed.
Steuern und Finanzierung
(1995)
Inhalt: I. Problemstellung 1. Die Relevanz von Steuern für die Finanzierung 2. Zur Entscheidungsneutralität von Steuern und zur Messung der Steuerbelastung 3. Finanzierungsrelevante Steuern II. Steuerliche Einflüsse auf die Außenfinanzierung 1. Beteiligungs- bzw. Einlagen finanzierung versus langfristige Kreditfinanzierung 2. Kurzfristige versus langfristige Kreditfinanzierung 3. Gesellschafter-Fremdfinanzierung 4. Leasing (als Alternative zum fremdfinanzierten Kauf) III. Steuerliche Einflüsse auf die Innenfinanzierung 1. Stille Selbstfinanzierung 2. Offene Selbstfinanzierung 3. Rückstellungen, insbes. Pensionsrückstellungen IV. Finanzplanung und Steuern V. Empirische Relevanz von Steuern für Finanzierungsentscheidungen
Manipulations of presentation time have a long history in research on the development of memory, with a number of paradoxical results deriving from methodological shortcomings as well as from insufficient theoretical specifications. After a look at some of the problems in earlier research, a psychophysics approach to investigate episodic memory functions is presented in which criterion-referenced manipulation of presentation time is used to estimate the effects of experimental manipulations and the effects of individual differences. Criterion'referenced presentation time (CRPT), defined as the time required to score at an a priori specified level of accuracy, is interpreted as a preliminary indicator of internal processing time. CRPTs are shown to be valid predictors of traditional measures of memory accuracy. Moreover, an extension of this psychophysics approach yields estimates of complete condition-specific timeaccuracy functions and of function-specific processing times (plus other parameters) for individual subjects. It is argued that both from a cognitive and a developmental perspective it is often advantageous to trade experimental equivalence in presentation times for functional equivalence in accuracy of performance; this applies not only to episodic memory processes.