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The production of food for a growing world population is a great challenge. In particular, protein and the long-chain n-3 fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), which exert a series of potential health effects, are scarce resources in the context of global food security. Fish from wild capture and aquaculture production cannot meet the current demand for EPA and DHA; therefore, a supplementation with alternative sources is crucial. Specific microalgae species have been shown to be a lucrative source of EPA, DHA, and protein, in particular, the oleaginous microalgae Nannochloropsis sp. and Phaeodactylum tricornutum. This study aimed to compare different cultivation scenarios of Nannochloropsis sp. and P. tricornutum with the production of aquaculture and capture fish as traditional sources of EPA and DHA in terms of environmental impacts. Scenarios included borosilicate glass and acrylic glass as photobioreactor (PBR) materials, two different tube diameters, and three different cultivation seasons. In these scenarios, carbon dioxide was modeled as an avoided burden. Additionally, all scenarios were modeled with the burdens resulting from carbon dioxide production. Environmental impacts of selected fish species were obtained from systematic literature research. Life cycle assessment following ISO 14040/44 was used to analyze the global warming potential, acidification, eutrophication, cumulative energy demand, water footprint, and land use. The system boundaries were set from "cradle-to-store," where the target store is located in Germany. Microalgae biomass as a source of EPA, DHA, and protein was found to have similar or lower environmental impacts than fish fillet from wild capture and aquaculture production when carbon dioxide was modeled as an avoided burden. Microalgae production that included the full burden of carbon dioxide production still caused similar or lower environmental impacts than aquaculture fish. It was found that the distinct microalgae species can significantly influence the results if the comparison is conducted based on nutritional values. Regarding the recommended daily intake of 250–500 mg EPA+DHA, microalgae are an advisable source of nutrients to lessen the environmental pressure on marine ecosystems. [ABSTRACT FROM AUTHOR]

Specific microalgae species are an adequate source of EPA and DHA and are able to provide a complete protein, which makes them highly interesting for human nutrition. However, microalgae cultivation has also been described to be energy intensive and environmentally unfavorable in pilot-scale reactors. Moreover, production in cold temperature zones has not been sufficiently investigated. In particular, the effects of tube materials and cultivation season length have rarely been previously investigated in the context of a comparative LCA of microalgae cultivation. A computational "top-down" model was conducted to calculate input flows for Nannochloropsis sp. and Phaeodactylum tricornutum cultivation in a hypothetical tubular photobioreactor. Cultivation processes were calculated according to detailed satellite climatic data for the chosen location in Central Germany. This model was applied to a set of different scenarios, including variations in photobioreactor material, tube diameter, microalgae species, and cultivation season length. Based on these data, a life cycle assessment (LCA) was performed following ISO standard 14040/44. The impact assessment comprised the global warming potential, acidification, eutrophication, cumulative energy demand, and water scarcity. The results showed that a long cultivation season in spring and fall was always preferable in terms of environmental impacts, although productivity decreased significantly due to the climatic preconditions. Acrylic glass as a tube material had higher environmental impacts than all other scenarios. The cultivation of an alternative microalgae species showed only marginal differences in the environmental impacts compared with the baseline scenario. Critical processes in all scenarios included the usage of hydrogen peroxide for the cleaning of the tubes, nitrogen fertilizer, and electricity for mixing, centrifugation, and drying. Microalgae cultivation in a tubular photobioreactor in a "cold-weather" climate for food is sustainable and could possibly be a complement to nutrients from other food groups. The added value of this study lies in the detailed description of a complex and flexible microalgae cultivation model. The new model introduced in this study can be applied to numerous other scenarios to evaluate photoautotrophic microalgae cultivation in tubular photobioreactors. Thus, it is possible to vary the facility location, seasons, scale, tube dimensions and material, microalgae species, nutrient inputs, and flow velocity. Moreover, single processes can easily be complemented or exchanged to further adjust the model individually, if, for instance, another downstream pathway is required. [ABSTRACT FROM AUTHOR]

Presents a study that examined the expression and functional activity of endogenous voltage-gated chloride (Cl) channels in glioma cells. Methods used in proving the importance of voltage-gated chloride channels for cell proliferation; Attempts made to demonstrate and analyze the expression of ClC-2, CLC-3 and ClC5 at the mNRA and protein levels and of patch-clamp recordings of chloride currents; Suggestions with regard to an upragulated occurrence of ClC-2 and CLC-3 channels in glioma membranes.

The purpose of this paper is to contribute to the definition of a European perspective on Digital Earth (DE), identify some actions that can contribute to raise the awareness of DE in the European context and thus strengthen the European contribution to the International Society for Digital Earth (ISDE). The paper identifies opportunities and synergies with the current policy priorities in Europe (Europe 2020, Innovation Union and Digital Agenda) and highlights a number of key areas to advance the development of DE from a European perspective: (1) integrating scientific research into DE; (2) exploiting the Observation Web with human-centred sensing; and (3) governance, including the establishment of stronger linkages across the European landscape of funding streams and initiatives. The paper is offered also as a contribution to the development of this new vision of DE to be presented at the next International DE Conference in Perth, Australia, in August 2011. The global recognition of this new vision will then reinforce the European component and build a positive feedback loop for the further implementation of DE across the globe. [ABSTRACT FROM AUTHOR]

The benthic protozoans were investigated along a transect in the eastern Mediterranean Sea from the Ionian to the Levantine Sea. Sediment samples were taken during Meteor cruise 25/1 in May and June 1993 at water depths of between 156 and 4617 m with a box corer and a multiple corer. A semi-quantitative cultivation technique was applied by placing sediment in petri dishes and diluting with sterile biotope water. Microscopic analyses of the protozoan taxa were conducted immediately after sampling, and then daily after enrichment with organic substrate. A total of 134 protozoan morphospecies were recorded, including 87 flagellates, 12 naked amoebae and 35 ciliates. 58% of the species could be attributed to genera known from shallow waters, demonstrating the wide distribution of these taxa. The number of recorded species per location ranged from 0 to 35 and decreased with increasing water depth. At stations deeper 1300 m very low species numbers as well as low potential abundances were recorded. Qualitative changes in the taxonomic composition with increasing depth were recorded as a decrease in the proportion of amoebae and euglenid flagellates and as an increase in the proportion of dinoflagellates. Ciliates were found down to a depth of 4260 m. The number of species was also dependent on the chloroplastic pigment equivalent (CPE), indicating a dependency on sedimented phytodetritus. The observed species included picophagous species, which feed mostly on bacteria, as well as nano- and microphagous species, which generally feed on protists, suggesting the existence of several trophic levels within the deep sea microbial food web. [Copyright &y& Elsevier]

Examines the response of internal transport barriers to central electron heating and current drive on Axi-symmetric divertor experiment. Application of central electron cyclotron heating and current drive to negative central shear discharges; Discussion on magnetohydrodymic stability.

The effect of the outer membrane (outer sheath) of Treponema denticola on bone resorption was studied. Bone resorption was measured by the release of previously incorporated 45Ca from the shafts of the radii and ulnae of 19-day fetal rats. A treated-over-control ratio (T/C ratio) significantly greater than 1 indicated the stimulation of bone resorption by the test substance. The addition of outer membrane of T. denticola increased the release of 45Ca from the assay bones. The minimum concentrations required to yield significant 45Ca release from the assay bones were 15, 22 and 75 μg protein/ml for serovars a, b and c, respectively. These protein values corresponded to estimated lipopolysaccharide contents of 0.6, 0.8 and 2.8 μg/ml, based on 3-deoxy-2-manno-octulosonate analysis. Heat treatment of outer membrane (60° for 30 min) did not change the effect on 45Ca release. Parathyroid hormone or prostaglandin E2, known to act synergistically with lipopolysaccharides in bone resorption, was also added to the assay system. Neither prostaglandin E2 at 10-7 M nor parathyroid hormone at 40 ng/ml, by itself, increased 45Ca release. However, in the presence of 10 μg protein/ml of outer membrane of serovar b at 120 h, the T/C ratio was increased to 1.31 ± 0.07 and 1.58 ± 0.118, respectively. These results suggest that a lipopolysaccharide-like material is present in the outer membrane of T. denticola that may be responsible for bone resorption in the in vitro system. [ABSTRACT FROM AUTHOR]