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Die Haftung der Kreditinstitute bei Finanzierung von Anteilen an geschlossenen Immobilienfonds
(2003)
Mixotrophs combine resource use to outcompete specialists: Implications for aquatic food webs
(2003)
The majority of species can be grouped into those relying solely on photosynthesis (phototrophy) or those relying solely on the assimilation of organic substances (heterotrophy) to meet their requirements for energy and carbon. However, a special life history trait exists in which organisms combine both phototrophy and heterotrophy. Such 'mixotrophy' is a widespread phenomenon in aquatic habitats and is observed in many protozoan and metazoan organisms. The strategy requires investment in both photosynthetic and heterotrophic cellular apparatus, but the benefits must outweigh these costs. In accordance with the mechanistic resource competition theory, laboratory experiments revealed that pigmented mixotrophs combined light and prey as substitutable resources. Thereby, they reduced prey abundance below the critical food concentration of competing specialist grazers [Rothhaupt, K. O. (1996) Ecology 77, 716-724]. Here, we demonstrate for the first time the important consequences of this strategy for an aquatic community. In the illuminated surface strata of a lake, mixotrophs reduced prey abundance so steeply that grazers from higher trophic levels, consuming both the mixotrophs and their prey, could not persist. Thus, the mixotrophs escaped from both competition and grazing, and remained dominant. Furthermore, the mixotrophs structured the prey abundance along the vertical light gradient creating low densities near the surface and a pronounced maximum of their algal prey at depth. Such deep algal accumulations are typical features of nutrient poor aquatic habitats, previously explained by resource availability. We hypothesize instead that the mixotrophic grazing strategy is responsible for deep algal accumulations in many aquatic environments.
The new animacy category in slavic languages : open questions of syntax, semantics and morphology
(2003)
The article gives an extensive analyses of the subgender animacy within the whole range of 12 Slavic languages and concentrates then on the new constructions with semantically inanimate nouns that indicate the Gen.-Acc.-case for animates (type Czech Petr si koupil Mercedesa(Gen.-Acc.) instead of Acc Mercedes. "Peter bought a Mercedes". A syntactic and semantic hierarchy of features that determine and drive the selectional properties is considered as well as the morphological (derivational) properties of these nouns. The languages under consideration are: Russian (including Old Russian), Ukrainian, Belorussian; Polish, Czech, Slovak, Lower and Upper Sorbian; Macedonian, Bulgarian, Slovenian and Serbo-Croatian.