pH effect on the susceptibility to parasitoid infection in the marine diatom Coscinodiscus spp. (Bacillariophyceae)

The pH on the frustule of individual cells of the marine centric diatoms Coscinodiscus granii and Coscinodiscus wailesii (Bacillariophyceae) was measured with pH microsensors in culture media with increasing pH values of 8.04, 8.14, and 8.22, respectively. In 85–96% of the C. granii cells the pH on the frustule was up to 0.4 units higher than that of the medium, reaching a maximum pH 8.95. Only in 2–3% the surface pH exceeded that of the medium by up to 0.7 pH units. These results strongly suggest that diatoms in batch cultures differ, at least temporarily, in their individual photosynthetic activities. Infection experiments with the parasitoid nanoflagellate Pirsonia diadema (Stramenopile) showed that flagellates failed to infect when the culture pH was 8.8 and above. pH measurements on freshly infected C. granii showed that the prevalence of infection was higher in tendency on diatoms with low surface pH. Application of these results to parasitoid-diatom interactions in natural waters suggests that within phytoplankton populations a strong photosynthetic activity might prevent diatom cells temporarily from infection by pH-sensitive parasitoids.     

Environmental equity and electric power generation: Disparate community outcomes within Texas?

The examinations conducted in this study focus at the community level to test for disparate outcomes involving utility-based electric power generation within the crucial state of Texas. Potential policy implications are discussed as relevant to the general thesis of environmental racism postulated by justice advocates and the civil rights strategies advanced by justice advocates. Cross-sectional and longitudinal perspectives are used in testing for distributive inequities involving locations of fossil fuel power plants and emissions and output rates of emissions originating from such power plants. These tests provide empirical basis for assessing outcomes of the siting and emissions regulatory processes. While the civil rights strategies that would use Title VI of the Civil Rights Act of 1964 and the disparate impact standard are inapplicable, some limited findings indicate disparate outcomes involving other disadvantaged populations that are difficult to justify in context of legitimate market dynamics. Issues raised in this study have relevance to national energy policy proposals that promote many more power plants across the USA and encourage emissions trading.     

An Ecologically Destabilized Environment: Its Effect on Small-Mammal Populations

Characteristics of the small-mammal populations inhabiting forest biocenoses in the Middle Ural state reserves have been analyzed over in the period from 1987 to 2002. During this period, the habitats of these animals were considerably destabilized due to windfalls and fires. The environmental characteristics of animal microhabitats at different stages of environment destabilization have been described quantitatively. Changes in the long-term cycles of the population dynamics of the dominant forest vole species caused by the destabilizing factors have been found. Redistribution of species dominance with respect to abundance has been demonstrated.     

Kenntnisdefizite bei Stoffeigenschaften und ihre Folgen

The data situation to chemical substances is unsatisfactory— in spite of in part considerable efforts in the last decades. One knows still very little on the subject of the dangerous characteristics of chemical substances. The consequences of this ignorance have primarily the employees to carry. They get sick due to a dealing with substances whose characteristics were not completely enlightened. But as well the enterprises have to suffer under it, after all, lose her experienced staff member and have to pay the costs about the Berufsgenossenschaften for these knowledge deficits. In the EU, the future European chemical policy is therefore discussed. The contribution explains the range of the sicknesses through dealing with substances with unknown characteristics.     

Lipopeptide als natürliche Adjuvantien für Impfstoffe aus Gram-negativen Bakterien

Bacterial cell wall components such as lipopolysaccharide, a variety of membrane proteins, murein, and lipoprotein can act as immunoadjuvants for bacterial vaccines, thus enhancing protection from bacterial infections. Synthetically prepared N-terminal parts of the lipoprotein from Enterobacteria carrying three fatty acid residues or lipopeptide analogs containing one to four aminoacids bound to S-glycerylcysteine act as potent immunoadjuvants in vivo in combination with or covalently linked to antiges. Here we demonstrate that the supplementation ofSalmonella vaccines with these synthetic lipopeptides significantly enhances their vaccine efficiency in mice. Variations in the native lipopeptide structure regarding chain length and amino acid sequence of the peptide moiety, as well as modifications of the lipoamino acid, lead to reduction or even complete loss of the adjuvant activity. The immunoadjuvant properties of the lipopeptides as described here are mediated by an enhancement of the humoral immune response.