Environmental assessment of the production and addition of bioethanol produced from <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> to gasoline in Chile

Purpose

Bioethanol is not currently produced in Chile. However, mixtures of bioethanol-gasoline at 2 and 5 % have been authorized. The production and use of the bioethanol-gasoline blend “E5” has been assessed using life cycle assessment (LCA) with the aim to compare the environmental profiles of bioethanol produced from Eucalyptus globulus with gasoline in Chile and to determine the potential of this biofuel-replacing gasoline in the transport sector.

Methods

The standard framework of LCA described by ISO was selected to assess the ecological burdens derived from the biofuel production using the SimaPro v7.8 software. The system boundaries included eucalyptus cultivation, bioethanol production, E5 blend production, and final use of E5. The inventory data for Eucalyptus cultivation were previously collected through surveys with forest managers. Inventory data for bioethanol production were obtained by process simulation models using Aspen Plus v7.1, and for non-simulated or modeled information, secondary information (scientific articles and reports) was used. Conventional gasoline, produced and used in Chile, was used as base scenario for comparison with E5 scenario.

Results and discussion

The environmental results showed reduction of the environmental impacts in most of the assessed categories when E5 blend is assessed and compared with gasoline. Reduction was evident for climate change, photochemical oxidation formation, terrestrial acidification, marine eutrophication, terrestrial ecotoxicity, marine ecotoxicity, depletion of water, and fossil resources. However, there was an increase in other impact categories, such as ozone layer depletion, human toxicity, terrestrial ecotoxicity, and marine eutrophication. The hotspots for E5 blend were the blending production and the combustion in the engine, whereas in the production process, the electricity production was the major contributor to most of the impact categories. When increasing the bioethanol content from E5 to E10 blend, the environmental impact increases in most of the evaluated categories except in the CC, WD, and FD categories. However, compared with other studies related to wood-based E10, the values for the environmental impacts obtained were lower than the reported.

Conclusions

The use of E5 blend can help to reduce the environmental impact in 8 of the 12 categories analyzed. Environmental impacts obtained are lower compared with other studies reported for E10 blend production from wood resources.

     

Nanostructure,composition and magnetic properties in soft and hard Co–Ni nanoparticles: The effect on the magnetic anisotropy

The magnetic properties of Co–Ni alloys nanoparticles with composition Co₈₀Ni₂₀ and Co₅₀Ni₅₀ and dispersed in a silica matrix are investigated. The effective magnetic anisotropies are evaluated from the analysis of the temperature dependence of the zero-field-cooling magnetizations and from the hysteresis loops at 3 K considering the coherent rotation model. The results show that, on the contrary of what expected, Co₈₀Ni₂₀ nanoparticles have smaller anisotropy than the Co₅₀Ni₅₀ one showing that the magnetic properties of the system can be tuned from soft to hard by simply adjusting the alloy composition. This behaviour can be explained on the basis of the different size and composition of the two systems. Moreover we found that the evaluation of the anisotropy constant depends on the experimental method adopted due to the modifications by interparticle dipolar interactions of the reversal process.     

Modulation of lyso-platelet activating factor:acetyl-CoA acetyltransferase from rat splenic microsomes. The role of cyclic AMP-dependent protein kinase

Incubation of rat splenic microsomes with the catalytic subunit of cyclic AMP-dependent protein kinase in the presence of Mg-ATP stimulated 2-3-fold lyso-platelet-activating factor:acetyltransferase activity. This activation was due to an increase in the $\text{V}{}_{\mathrm{<mtext>max</mtext>}}$ of the acetylation reaction, whereas the $\text{K}{}_{\mathrm{<mtext>m</mtext>}}$ for acetyl-CoA was not affected. The ATP derivative, AMPPNP, could not replace ATP and preincubation of the microsomes with the heat-stable inhibitor of protein kinase prevented the activation by Mg-ATP obtained in the presence of the protein kinase. Activation of the acetylation reaction by the protein kinase was reversible. Evidence is provided that the reversal of activation is due to dephosphorylation of the enzyme. These data provide evidence that in vitro lyso-platelet-activating factor:acetyltransferase from splenic microsomes is regulated by phosphorylation.     

Antibiotic-Resistant Organisms Cultured from Atlantic Bottlenose Dolphins (Tursiops truncatus) Inhabiting Estuarine Waters of Charleston, SC and Indian River Lagoon, FL

Bottlenose dolphins (Tursiops truncatus) from estuarine waters of Indian River Lagoon, FL (IRL) and Charleston, SC (CHS) were cultured to screen for microorganism colonization and to assess antibiotic sensitivity. Swabs (n = 909) were collected from the blowhole, gastric fluid, and feces of 171 individual dolphins The most frequently cultured organisms were Plesiomonas shigelloides (n = 161), Aeromonas hydrophila (n = 144), Escherichia coli (n = 85), and Pseudomonas fluorescens (n = 82). In descending frequency, organisms demonstrated resistance to erythromycin, ampicillin, and cephalothin. Human and animal pathogens resistant to antibiotics used in human and veterinary medicine were cultured. Escherichia coli (E. coli) more often was resistant in IRL dolphins. Three cases of methicillin-resistant Staphylococcus aureus (MRSA) were found at CHS. Emergence of antibiotic resistance is not confined to humans. Bottlenose dolphins may serve as sentinels for transfer of resistance from humans and animals or indicate that antibiotics are reaching the marine environment and causing resistance to emerge through selective pressure and genetic adaptation.     

Isozyme diversity in some Canarian woody endemisms of the genus Echium L. (Boraginaceae)

Oceanic archipelagos are considered hot-spots of biodiversity because they harbor unique biota with a high level of endemicity. However, the endemic biodiversity of oceanic islands is very vulnerable to extinction. In recent decades, intensive exploitation of these territories and human-mediated introduction of alien species have posed unprecedented threats to the long-term survival of the endemic contingent. The very limited population genetic information available until now for the 28 Canarian endemic Echium taxa has hindered the development of conservation strategies for the ca. 25% of them that are under threat. In this paper, we analyze the levels and distribution of genetic isozyme diversity in 23 natural populations of three endangered endemics of restricted distribution (E. acanthocarpum, CR; E. onosmifolium ssp. spectabile, EN; and E. callithyrsum, VU), and two endemics of wide distribution and in principle free of threat (E. decaisnei and E. onosmifolium). Our results reveal high levels of genetic variability in all these taxa that have plausibly been reached despite a predominance of selfing. They also point out a high incidence of inbreeding in the reproductive dynamics of populations and suggest the potential value of hybridisation processes in shaping the genetic makeup of these species. Among-population differentiation, as estimated by Gst, and genetic distances within taxa are low overall, but they do support the current taxonomic separation between the two subspecies of E. onosmifolium and do not furnish evidence that the current status of the endangered species may be attributed to genetic factors. We use the genetic parameters to suggest some guidelines to help implement a conservation strategy of these taxa.     

Aluminum accumulation and its relationship with mineral plant nutrients in 12 pteridophytes from Venezuela

The purpose of this study was to investigate the aluminum (Al) concentration in Lycopodium clavatum, Dicranopteris flexuosa, Sticherus nudus, Anemia villosa, Cyathea gibbosa, Pteridium arachnoideum, Pteris vittata, Thelypteris dentata, Blechnum occidentale, Elaphoglossum sporadolepis, Nephrolepis cordifolia and Polypodium pseudoaureum, species from 11 families with different phylogenetic position, found on soils with a high concentration of Al (up to 13 g kg^?1 dry mass (DM)). When Al concentration and mineral nutrients in aerial organs were considered, pteridophytes were classified into three groups: group one included pteridophytes with Al concentrations over 1000 mg kg^?1 DM in their aerial organs, a ratio between Al and essential plant nutrients such as Ca, Mg and P higher than one and a K/Al ratio between 0.68 and 2.56 mol mol^?1. In group 1 was the well known Al-accumulator L. clavatum (Lycophyte) as well as the Neotropical ferns D. flexuosa, S. nudus (both basal leptosporangiate ferns), and C. gibbosa (core leptosporangiate tree fern). Group 2, ferns which accumulate Al over 1000 mg kg^?1 DM in their fronds, and had an Al/Ca and Al/Mg ratio <1. Species in this group included E. sporadolepis and N. cordifolia (derived polypod ferns). Group 3, ferns classified as Al-excluders, showing Al concentration <782 mg kg^?1 DM in the fronds, had Al/Ca and Al/Mg ratios <1, Al/P ratio ≤1 and a K/Al ratio between 18.10 and 80.36 mol mol^?1. In group 3, were A. villosa (basal leptosporangiate fern) and the derived polypod ferns P. arachnoideum, P. vittata, T. dentata, B. occidentale and P. pseudoaureum. The translocation factor of Al from subterranean to aerial organs was up to 4 in S. nudus, and subterranean organs from E. sporadolepis showed the highest concentration of Al (12 g kg^?1 DM). We coincide with early literature in that other criteria in addition to the Al concentration should be considered to define the Al accumulation, such as its relationship with macronutrients. For example, we propose the inclusion of K/Al ratio. We conclude that out of six Al-excluders five belonged to the derived polypods while two species from Polypodiales showed high Al concentrations. We reconfirm accumulation of Al in L. clavatum and C. gibbosa and discover two new Al-accumulating species in the more ancient ferns: S. nudus and D. flexuosa.     

Premotor nonspiking neurons regulate coupling among motoneurons that innervate overlapping muscle fiber population

Recent work indicated that co-activity of different motoneurons (MNs) in the leech can be regulated through a network that is centered on a pair of nonspiking (NS) neurons. Here, we investigate whether this effect generalizes to different types of MNs that display differential co-activity patterns in different motor behaviors: the dorsal longitudinal excitors DE-3 and the dorsal and ventral excitors MN-L. The data indicates that both motoneurons are coupled to the NS neurons through rectifying junctions that are activated when the motoneuron membrane potential becomes more negative than that of the NS, and that they exert an inhibitory synaptic potential on NS via a polysynaptic pathway. In addition, DE-3 and MN-L are linked by junctions that allow mutual excitation but the transmission of excitatory signals from MN-L to DE-3 depended on NS membrane potential. The results support the view that NS neurons can play a central role in orchestrating the co-activity of MNs during motor behaviors.