This study examines synchronous computer-mediated communication (SCMC) discourse in a bilingual chat setting consisting of Spanish-speaking learners of English and Englishspeaking learners of Spanish. Participants were members of a telecollaboration involving 80 students at North Carolina State University and the University of Puerto Rico. Data were derived from two chat groups, one of four students and the other of five students, engaged in nine 1-hour chat sessions (a half hour in English and a half hour in Spanish). The ecological affordance construct (van Lier, 1996, 2000) frames three research questions: (a) What types of linguistic affordances emerge in the bilingual chat sessions? (b) How do learners respond to linguistic affordances provided by native speakers? and (c) What are learners' perceptions regarding linguistic affordances in their chat discourse? Findings reveal that participants provide a range of affordances to each other, although affordances appear to have a limited role in the overall telecollaborative context.

Agriculture is a diverse field that produces a wide array of products vital to society. As global populations continue to grow the competition for natural resources will increase pressure on agricultural production of food, fiber, energy, and various high value by-products. With elevated concerns related to environmental impacts associated with the needs of a growing population, a life cycle assessment (LCA) framework can be used to determine areas of greatest impact and compare reduction strategies for agricultural production systems. The LCA methodology was originally developed for industrial operations but has been expanded to a wider range of fields including agriculture. There are various factors that increase the complexity of determining impacts associated with agricultural production including multiple products from a single system, regional and crop specific management techniques, temporal variations (seasonally and annually), spatial variations (multilocation production of end products), and the large quantity of nonpoint emission sources. The lack of consistent methodology of some impacts that are of major concern to agriculture (e.g., land use and water usage) increases the complexity of this analysis. This paper strives to review some of these issues and give perspective to the LCA practitioner in the field of agriculture.

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The accurate characterization of biomass is critical for development of bioenergy feedstocks and their utilization. Most analytical approaches involve acid hydrolysis of the polysaccharides in biomass, leaving most of the lignin as insoluble residue. A limitation of this approach is that the same conditions used to hydrolyze polysaccharides also degrade the liberated monosaccharides. The NREL-compiled procedures account for this effect with “Sugar Recovery Standards”, in which a solution of the expected monosaccharides is prepared and subjected to the dilute-hydrolysis portion of the procedure; however, this tends to overestimate monosaccharide degradation and introduce bias between polysaccharides of different lability. The following recommended method modifications are intended to reduce these errors: (1) quantification of immediate degradation products of monosaccharides and their stoichiometric addition to the monosaccharide yield; (2) the adjustment of this combined yield with sugar recovery standards; and (3) preautoclave analysis of hydrolyzates to improve the estimation of monosaccharide concentration profiles for adjustment calculations.