University of Maine

About: University of Maine is a education organization based out in Orono, Maine, United States. It is known for research contribution in the topics: Population & Ice sheet. The organization has 8637 authors who have published 16932 publications receiving 590124 citations. The organization is also known as: University of Maine at Orono.

Butanol production from lignocellulosics

Abstract: Clostridium spp. produce n-butanol in the acetone/butanol/ethanol process. For sustainable industrial scale butanol production, a number of obstacles need to be addressed including choice of feedstock, the low product yield, toxicity to production strain, multiple-end products and downstream processing of alcohol mixtures. This review describes the use of lignocellulosic feedstocks, bioprocess and metabolic engineering, downstream processing and catalytic refining of n-butanol.

Tradeoffs Between Local Taxes and Government Spending as Determinants of Business Location

Abstract: This paper investigates the effects of local fiscal policy on the location decisions of 3,763 establishments that began operations in Maine between 1993 and 1995. Empirical results, estimated from Poisson and negative binomial regression models, indicate that businesses favor municipalities that spend high amounts on public goods and services, even when these expenditures are financed by an increase in local taxes. This suggests that a local fiscal policy of reduced government spending, to balance a tax cut, may attract fewer new businesses than a policy featuring additional spending and higher taxes.

Catchment land‐use, macroinvertebrates and detritus processing in headwater streams: taxonomic richness versus function

Abstract: 1. We used a litter bag technique to assess the effect of catchment land-use (forest, wetland, agriculture, urban) on the processing of red maple (Acer rubrum L.) litter in 17 streams in Maine, U.S.A. Litter processing by fungi was predicted to increase with nutrient concentrations along a gradient of land use, from relatively unmodified to highly modified. Litter processing by litter-shredding macroinvertebrates was predicted to decline along this gradient because of a decline in their taxonomic richness and biomass. 2. Land use was associated with the anticipated gradient in nutrient and macroinvertebrate attributes, and a significant relationship was found between land use and nitrate concentration. There was, however, no significant relationship between land use and soluble reactive phosphorus (SRP) concentration. Similarly, shredder taxonomic richness was significantly related to land use type, whereas shredder biomass showed no significant relationship to land use. 3. Attributes of the shredder assemblage structure and nutrient concentrations were both strong determinants of litter processing. Increasing biomass and taxonomic richness of shredders was significantly related to increasing rates of litter mass loss. Increasing concentrations of nitrate and SRP were significantly related to increasing rates of litter softening below threshold concentrations (approximately 0.20 mg NO3-N L–1 and 5 μg SRP L–1). 4. The potentially additive effects of nitrate and SRP concentrations or shredder richness and biomass on litter processing rates were confounded by the lack of significant correlation between these pairs of variables. Consequently, rates of litter processing (as rates of softening or mass loss) did not vary systematically among different land use regimes.

Pyrrolizidine alkaloids as larval feeding deterrents for spruce budworm, Choristoneura fumiferana (Lepidoptera: Tortricidae)

Abstract: Sixth instars of the spruce budworm, Choristoneura fumiferana (Clemens), were exposed to an ethanol extract of roots of the composite coltsfoot, Tussilago farfara L., in a laboratory feeding bioassay. The extract had feeding deterrent activity, and the active ingredient, senkirkine, was isolated. Senkirkine, a pyrrolizidine alkaloid, is to our knowledge the first member of this class of compounds shown to have feeding deterrent activity in Lepidoptera. Thirteen additional pyrrolizidine alkaloids were bioassayed to determine possible structure-activity correlations. Most of the pyrrolizidine alkaloids tested were inactive, and high levels of feeding deterrence were not observed in those compounds lacking lactone or diester side chains. The most active compounds, senkirkine and lasiocarpine, bore α, β unsaturation in the side chain.