In this article, we attempt to estimate the contemporary phytoplankton species pool of a particular lake, by assessing the rate of floral change over a period of 15 years. Phytoplankton time series data from Lake Stechlin, an oligo-mesotrophic lake in the Baltic Lake District (Germany) were used. Of the 254 algal species recorded during the 15-year of studies with roughly biweekly sampling, 212 species were planktonic. In the individual plankton years, the recorded total number of species changed between 97 and 122, of which the number of dominants ([1% contribution to the annual average of total biomass) was only 10-19. The 15-year cumulative number of species exhibited an almost linear increase after an initial saturation phase. This increase was attributed to two reasons: increase of sample size and immigration of species new to the flora. Based on a probabilistic model developed in this study, we estimated the number of co-existing planktonic species of the lake as some 180, and the rate of floral change as 1-2 species per year. Of these coexisting species, only few maintain the matter-energy processing ecosystem functions in any particular plankton year. Selection of these dominants is probably driven by mesoclimatic cycles, coupled with human-induced forcing, like eutrophication. All others are hiding as an ecological memory, in the sense of the capacity or experiences of past states to influence present or future responses of the community. Data analyses suggest that selection of the 'memory species' that show temporary abundance increases over shorter (several years) periods are Electronic supplementary material The online version of this article (largely dependent upon the dominants. These results show that interspecific interactions and the particular autecological features of the dominants, together with their effects on the whole ecosystem, act as a major organizing force. Some phytoplankton species, like Planktothrix rubescens, are efficient ecosystem engineers with cascading effects of both a top-down and bottom-up nature. Historical scientific data on Planktothrix blooms in Lake Stechlin suggest cyclic patterns in long-term development of phytoplankton which, as the legend of the Red Cock suggests, dates back much further than scientific archives.

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Molten commercial aluminium was oast in sand mould in the presence of high electric current. Grain refinement was enhanced as the current was increased. In case of alternating external magnetic field, however, there was no proportionality between the refinement and magnetic field strength. The ingot acquired fine equiaxed grains when the magnetic field was about 0.3 kilo gauss. At all other values, ingots showed mixed structure of equiaxed and columnar areas to varying proportions. The ingot cast in this experiment was about 100g.The behaviour of the 4-kg ingot cast in an experimental semi-continuous casting machine was almost the same.The number of grains/cm2 in both experiments was about 700.

Prevalently occur in electronic components, which are also programmable analog circuits. Particularly promising is a symbiosis in which the circuit can be programmed and cooperation of a microcontroller can be realized. Because of these types of devices are becoming more common, a classic circuit and system techniques storey enjoying a renaissance, which was previously difficult to achieve because of the much less important.Typical such application the robust electronics analog systems. Its function then efficient, if the electronic circuit is certain his behavior, its certain parameters, the changed according to conditions, we can modify it. If we place an embedded controller in the environment of the analogous system, that for us important parameters values it, then the controller because of depends of an algorithm, it may intervene in the function of an analogous electronic circuit. We place one or more programmable system on chip (PSoC) 1 circuit -mostly inside of a microcontroller-if it is analogous in an electronic circuit system, on suitable places, then these parametrical and you are topology configuring we may intervene very efficiently[5] [2].Other hand, the use of Field Programmable Analog Arrays (FPAA) or newer version of them, PSoC device suggests on a great opportunity to give additional advantages. More great opportunity is the co-operation of the PSoC's microcontrollers. It is very important to develop such an architecture that allows maximum flexibility and circuit-freedom too[3].