Improvements in Life Cycle Energy Efficiency and Greenhouse Gas Emissions of Corn-Ethanol

Corn-ethanol production is expanding rapidly with the adoption of improved technologies to increase energy efficiency and profitability in crop production, ethanol conversion, and coproduct use. Life cycle assessment can evaluate the impact of these changes on environmental performance metrics. To this end, we analyzed the life cycles of corn-ethanol systems accounting for the majority of U.S. capacity to estimate greenhouse gas (GHG) emissions and energy efficiencies on the basis of updated values for crop management and yields, biorefinery operation, and coproduct utilization. Direct-effect GHG emissions were estimated to be equivalent to a 48% to 59% reduction compared to gasoline, a twofold to threefold greater reduction than reported in previous studies. Ethanol-to-petroleum output/input ratios ranged from 10:1 to 13:1 but could be increased to 19:1 if farmers adopted high-yield progressive crop and soil management practices. An advanced closed-loop biorefinery with anaerobic digestion reduced GHG emissions by 67% and increased the net energy ratio to 2.2, from 1.5 to 1.8 for the most common systems. Such improved technologies have the potential to move corn-ethanol closer to the hypothetical performance of cellulosic biofuels. Likewise, the larger GHG reductions estimated in this study allow a greater buffer for inclusion of indirect-effect land-use change emissions while still meeting regulatory GHG reduction targets. These results suggest that corn-ethanol systems have substantially greater potential to mitigate GHG emissions and reduce dependence on imported petroleum for transportation fuels than reported previously.     

Effects of light and turbidity on feeding,growth, and survival of larval Delta Smelt (Hypomesus transpacificus,Actinopterygii, Osmeridae)

Hydrobiologia - Understanding how environmental factors—here, light intensity and turbidity—influence the feeding, growth, and survival of larval Delta Smelt is critical for optimizing...     

Replication-competent gamma-retrovirus Mo-MuLV expressing green fluorescent protein as efficient tool for screening of inhibitors of retroviruses that use heparan sulfate as primary cell receptor

The effect of sulfated polysaccharides on the efficiency of the infection of mouse transplantable fibroblast SC-1 and NIH-3T3 cell lines by replication-competent recombinant Moloney murine leukemia virus (Mo-MuLV), which carries the eGFP gene, was investigated. It was found that sulfated polysaccharides have no cytostatic and cytotoxic effects on SC-1 and NIH-3T3 cells in the concentration range of 0.01–100 μg/mL and have virucidal activity against Mo-MuLV. Polysaccharides in the indicated concentrations inhibit Mo-MuLV infection that prevents the further development of viral infection. It was shown that sulfated polysaccharides are also effective inhibitors of other retroviruses, including lentiviruses, which use sulfated polysaccharides as primary cell receptors.     

Gadolinium chloride-induced shifts in intrahepatic distributions of liposomes

Intravenously administered gadolinium chloride caused only a slight decrease in the rate of elimination of small unilamellar liposomes from the blood and had no influence on the total hepatic uptake of these vesicles, but did alter their intrahepatic distribution substantially. Uptake by the non-parenchymal cells was substantially decreased, whereas uptake by the parenchymal cells showed a concomitant increase. Our earlier observations (Roerdink et al. (1981) Biochim. Biophys. Acta 677, 79-89) on the effect of lanthanides on the in vivo distribution of multilamellar liposomes have been extended, in that we demonstrate, in addition to the drop in elimination rate from the blood and in the over-all hepatic uptake, a shift of liposome distribution within the Kupffer cell population. While the larger Kupffer cells, which normally take up a major fraction of an injected liposome dose, were strongly inhibited in liposome uptake, the more numerous small macrophages showed a 3-4-fold increase in uptake.     

The prokaryotic neomycin-resistance-encoding gene acts as a transcriptional silencer in eukaryotic cells

The gene encoding neomycin resistance (neo) mediates a cis-acting negative effect on expression from promoters in transient and stable transfectants of mammalian cell lines. Inserting the neo gene either into retroviral vectors or into plasmids containing reporter genes results in a five- to tenfold decrease of expression from proximal promoters like the simian virus 40 early or the retroviral myeloproliferative sarcoma virus promoter. The silencing effect is not dependent on the insertion site or the orientation of the fragment. The neo gene is frequently used in eukaryotic vectors as a dominant selectable gene. Other selectable genes were tested for potential cis-activity. We found that the gene conferring resistance to puromycin from Streptomyces alboniger does not influence adjacent promoters.