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Papiliotrema huenov was previously reported to be highly tolerant of a range of extremely toxic heavy metals. This study aimed to identify the potential of P. huenov to remove manganese and copper from aqueous solution. Physical conditions which affect removal of Mn(II) and Cu(II) were determined. Optimal temperature for adsorption of both metal ions was 30 °C, and optimal pH for maximum uptake of Mn(II) and Cu(II) were 5 and 6, respectively. Under these conditions, living cells of P. huenov accumulated up to 75.58% of 110mg/L Mn(II) and 70.5% of 128mg/L Cu(II) over 120 h, whereas, the removal efficiency of metal ions by dead cells over 1 h was 60.3% and 56.5%, respectively. These results indicate that living cells are more effective than dead biomass for bioremediation, but that greater time is required. The experimental data extends the potential use of P. huenov in biosorption and bioaccumulation of toxic heavy metals to copper and manganese, two of the most common industrial contaminants. [ABSTRACT FROM AUTHOR]

We analyze the performance of firms from the German business-related service sector for 1994-2000. Performance is measured by ordinal assessment of changes in total sales. We estimate first-order Markov chain models using extensions of the multinomial logit model: a linear index model with alternative specifications of heterogeneity and a semiparametric model. The preferred specification involves heterogeneity connected to the firm and the type of transition. Our findings include that size has a positive effect on performance, young firms outperform older competitors, a single creditor has a stabilizing effect, diversification has a negative impact, and performance is significantly affected by legal status. Measuring performance through profit rather than sales does not alter the qualitative results. [ABSTRACT FROM AUTHOR]