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Die Nachhaltigkeit des Waldes wird heute im Allgemeinen als die gleichrangige Berücksichtigung ökonomischer, ökologischer und sozialer Waldfunktionen beschrieben. Insbesondere das Konzept des naturnahen Waldbaus "verbindet in hohem Maße die verschiedenen ökonomischen, ökologischen und sozialen Teilziele der Nachhaltigkeit" (Kleinschmit 2007: 133). Die in der Praxis teilweise zu beobachtende übermäßige Ausrichtung an ökonomischen Gesichtspunkten und an der Sicht auf den Wald als primären Holzproduzenten wird von vielen Akteuren und Akteurinnen kritisiert; im Zuge des Klimawandels und der Klimawandelforschung rücken zwar die ökologischen Funktionen des Waldes – bspw. als Kohlenstoffsenke, Biodiversitäts-Potential, aber auch als Energieressource – mehr in den Blickpunkt. Wie steht es jedoch um den dritten Pfeiler der Nachhaltigkeit, die sozialen Funktionen des Waldes? Ulrich Schraml (Forstpolitikwissenschaftler an der Universität Freiburg) zufolge "führen die sozialen Funktionen des Waldes neben Walderhaltung, Sicherung der Biodiversität, Rohstoffversorgung und den Klimaprogrammen in den laufenden Prozessen ein Schattendasein" (Schraml 2009: 2). Der vorliegende Text wird sich diesem "blinden Fleck" der aktuellen forstwissenschaftlichen Forschung zuwenden und die Frage stellen, (1) welche sozialen Funktionen der Wald erfüllen soll und (2) wie diese gewährleistet werden können. Während erstere Fragestellung auf den gesellschaftlichen Anspruch an Wald, d.h. auf die Art und Weise der sozialen Nutzung, abzielt, erfordert letztere den Einbezug forstpolitischer Rahmenbedingungen und deren Verhältnis zur Sicherstellung dieser Nutzungsformen. Die Frage lautet also, wie sich die Veränderung der forstpolitischen Rahmenbedingungen auf die sozialen Funktionen der Wälder und auf die Möglichkeiten sozialer Nutzungen auswirken oder in Zukunft auswirken könnten. ...
In this work we present the setup and first tests of our new BIO IN detector. This detector is designed to classify atmospheric ice nuclei (IN) for their biological content. Biological material is identified via its auto-fluorescence (intrinsic fluorescence) after irradiation with UV radiation. Ice nuclei are key substances for precipitation development via the Bergeron–Findeisen process. The level of scientific knowledge regarding origin and climatology (temporal and spatial distribution) of IN is very low. Some biological material is known to be active as IN even at relatively high temperatures of up to –2°C (e.g. pseudomonas syringae bacteria). These biological IN could have a strong influence on the formation of clouds and precipitation. We have designed the new BIO IN sensor to analyze the abundance of IN of biological origin. The instrument will be flown on one of the first missions of the new German research aircraft ''HALO'' (High Altitude and LOng Range).
Gauging risk with higher moments : handrails in measuring and optimising conditional value at risk
(2009)
The aim of the paper is to study empirically the influence of higher moments of the return distribution on conditional value at risk (CVaR). To be more exact, we attempt to reveal the extent to which the risk given by CVaR can be estimated when relying on the mean, standard deviation, skewness and kurtosis. Furthermore, it is intended to study how this relationship can be utilised in portfolio optimisation. First, based on a database of 600 individual equity returns from 22 emerging world markets, factor models incorporating the first four moments of the return distribution have been constructed at different confidence levels for CVaR, and the contribution of the identified factors in explaining CVaR was determined. Following this the influence of higher moments was examined in portfolio context, i.e. asset allocation decisions were simulated by creating emerging market portfolios from the viewpoint of US investors. This can be regarded as a normal decisionmaking process of a hedge fund focusing on investments into emerging markets. In our analysis we compared and contrasted two approaches with which one can overcome the shortcomings of the variance as a risk measure. First of all, we solved in the presence of conflicting higher moment preferences a multi-objective portfolio optimisation problem for different sets of preferences. In addition, portfolio optimisation was performed in the mean-CVaR framework characterised by using CVaR as a measure of risk. As a part of the analysis, the pair-wise comparison of the different higher moment metrics of the meanvariance and the mean-CVaR efficient portfolios were also made. Throughout the work special attention was given to implied preferences to the different higher moments in optimising CVaR. We also examined the extent to which model risk, namely the risk of wrongly assuming normally-distributed returns can deteriorate our optimal portfolio choice. JEL Classification: G11, G15, C61
According to the metalexicographical theory, there are three main components in a semasiological dictionary: macro-, micro- and middles structure. The aim of this article is to describe and analyze the microstructure of three general semasiological dictionaries of the German language. As methodological framework, it takes in account the distinction between formal and semantic comment and between definition and density of the constant information program.
Resenha : Karl-Heinz Göttert. Neues Deutsches Wörterbuch. Köln: Helmut Lingen Verlag, 2007 (1150 p.)
(2009)
Aptamers that can be regulated with light allow precise control of protein activity in space and time and hence of biological function in general. In a previous study, we showed that the activity of the thrombin-binding aptamer HD1 can be turned off by irradiation using a light activatable "caged" intramolecular antisense-domain. However, the activity of the presented aptamer in its ON state was only mediocre. Here we studied the nature of this loss in activity in detail and found that switching from 5'- to 3'-extensions affords aptamers that are even more potent than the unmodified HD1. In particular we arrived at derivatives that are now more active than the aptamer NU172 that is currently in phase 2 clinical trials as an anticoagulant. As a result, we present light-regulatable aptamers with a superior activity in their ON state and an almost digital ON/OFF behavior upon irradiation.
Waldlaubsänger
(2009)