Big Data Analytics is an emerging field since massive storage and computing capabilities have been made available by advanced e-infrastructures. Earth and Environmental sciences are likely to benefit from Big Data Analytics techniques supporting the processing of the large number of Earth Observation datasets currently acquired and generated through observations and simulations. However, Earth Science data and applications present specificities in terms of relevance of the geospatial information, wide heterogeneity of data models and formats, and complexity of processing. Therefore, Big Earth Data Analytics requires specifically tailored techniques and tools. The EarthServer Big Earth Data Analytics engine offers a solution for coverage-type datasets, built around a high performance array database technology, and the adoption and enhancement of standards for service interaction (OGC WCS and WCPS). The EarthServer solution, led by the collection of requirements from scientific communities and international initiatives, provides a holistic approach that ranges from query languages and scalability up to mobile access and visualization. The result is demonstrated and validated through the development of lighthouse applications in the Marine, Geology, Atmospheric, Planetary and Cryospheric science domains.

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Bacterial inactivation by 405 nm light is accredited to the photoexcitation of intracellular porphyrin molecules resulting in energy transfer and the generation of reactive oxygen species that impart cellular oxidative damage. The specific mechanism of cellular damage, however, is not fully understood. Previous work has suggested that destruction of nucleic acids may be responsible for inactivation; however, microscopic imaging has suggested membrane damage as a major constituent of cellular inactivation. This study investigates the membrane integrity of Escherichia coli and Staphylococcus aureus exposed to 405 nm light. Results indicated membrane damage to both species, with loss of salt and bile tolerance by S. aureus and E. coli, respectively, consistent with reduced membrane integrity. Increased nucleic acid release was also demonstrated in 405 nm light-exposed cells, with up to 50 % increase in DNA concentration into the extracellular media in the case of both organisms. SYTOX green fluorometric analysis, however, demonstrated contradictory results between the two test species. With E. coli, increasing permeation of SYTOX green was observed following increased exposure, with >500 % increase in fluorescence, whereas no increase was observed with S. aureus. Overall, this study has provided good evidence that 405 nm light exposure causes loss of bacterial membrane integrity in E. coli, but the results with S. aureus are more difficult to explain. Further work is required to gain greater understanding of the inactivation mechanism in different bacterial species, as there are likely to be other targets within the cell that are also impaired by the oxidative damage from photo-generated reactive oxygen species.

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Summary The cytotoxic properties of quinones, such as menadione, are mediated through one electron reduction to yield semi-quinone radicals which can subsequently enter redox cycles with molecular oxygen leading to the formation of reactive oxygen radicals. In this study the role of reduction and oxidation in the toxicity of mitoxantrone was studied and its toxicity compared with that of adriamycin and menadione. The acute toxicity of mitoxantrone was not mediated through one-electron reduction, since inhibition of the enzymes glutathione reductase and catalase, responsible for protecting the cells against oxidative damage, did not affect its toxicity. Adriamycin was the most potent inhibitor of protein and RNA synthesis of the three quinones. Menadione, at concentrations up to 25 ftM, did not inhibit either protein or RNA synthesis unless dicoumarol, an inhibitor of DT-diaphorase, was also present. The two-electron reduction of menadione by DT-diaphorase is therefore a protective mechanism in the cell. This enzyme also protected against the toxicity of high concentrations (100 pM) of mitoxantrone. The inhibitory effect of mitoxantrone, but not of menadione or adriamycin, on cell growth was prevented by inhibiting the activity of cytochrome P450-dependent mixed function oxidase (MFO) system using metyrapone. This suggests that mitoxantrone is oxidised to a toxic intermediate by the MFO system.

The cytochrome P-450 content of rat hepatocytes declined rapidly over 72 h in culture, due primarily to denaturation to cytochrome P-420. Six different media were investigated for their ability to conserve cytochrome P-450 during culture, and the most successful was a modified Earle's medium. After 72 h culture in this medium, cytochromes P-450 and b, NADH~~~~orne b, and NADPH~yt~hrome c-reductases were maintained at 40, 100, 35 and 52% of fresh cell values, respectively. Cytochrome P-450 showed differential functional stability during culture with ethoxyresorufin O-deethylation being more stable than either pentoxyphenoxazone O-depentylation or biphenyl Chydroxylation. Monooxygenase activities declined faster than did cytochrome P-450 content. This discrepancy was not explained by loss of the flavin nucleotides, FMN or FAD.Cytochrome P-450 aged-fiction oxidase NADH-cytochrome bs reductase ~ADPH-cyto~hrome c reductase

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1. Human hepatocytes were cryopreserved for up to 14 days at -80 degrees C and the cryoprotection offered by different media investigated in terms of post-thaw cell viability and function. 2. Optimal cryoprotection was offered by a solution containing dimethylsulphoxide, propylene glycol, acetamide and polyethylene glycol 8000 in Leibowitz L15 medium. 3. The cytochrome P450 content and activities of the microsomal P450 dependent mixed function oxidase system were well maintained at above 70% of fresh cell values throughout the cryopreservation period. However, the activities of the cytosolic enzymes studied, glutathione S-transferase and glutathione reductase, were not well maintained; they declined to < 40% of fresh cell values after storage of cells for 14 days at -80 degrees C. The membrane environment may protect microsomal enzymes from denaturation by freeze-thaw damage. 4. After cryopreservation, viability of human hepatocytes was higher than that of rat hepatocytes preserved under identical conditions. For human cells maximum post-cryopreservation viability was 67% after 24 h at -80 degrees C; this declined to 49% after 14 days storage at -80 degrees C. In addition post-cryopreservation human hepatocytes remained > 70% viable when incubated at 37 degrees C in suspension compared with only 46% of rat hepatocytes. This indicates that human hepatocytes can withstand freeze-thaw damage better than those from rat. 5. The results of this study define optimal conditions for cryopreserving human hepatocytes. Although microsomal enzyme activities are retained post-cryopreservation, the decrease in viability of thawed cells upon incubation at 37 degrees C suggests that caution should be exercized when using cryopreserved cells to study integrated drug metabolizing pathways in man in vitro.