7 resultados para New production

em Brock University, Canada


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How does fire affect the plant and animal community of the boreal forest? This study attempted to examine the changes in plant composition and productivity, and small mammal demography brought about by fire in the northern boreal environment at Chick Lake, N.W.T. (65053fN, 128°14,W). Two 5*6 ha plots measuring 375m x 150m were selected for study during the summers of 1973 and 197^. One had been unburned for 120 years, the other was part of a fire which burned in the spring of 1969. Grids of 15m x 15m were established in each plot and meter square quadrats taken at each of the 250 grid intersections in order to determine plant composition and density. Aerial primary production was assessed by clipping and drying 80 samples of terminal new production for each species under investigation. Small mammal populations were sampled by placing a Sherman live trap at each grid intersection for ten days in every month. The two plots were similar in plant species composition which suggested that most regrowth in the burned area was from rootstocks which survived the fire. The plant data were submitted to a cluster analysis that revealed nine separate species associations, six of which occured in the burned area and eight of which occured in the control. These were subsequently treated as habitats for purposes of comparison with small mammal distributions. The burned area showed a greater productivity in flowers and fruits although total productivity in the control area was higher due to a large contribution from the non-vascular component. Maximum aerial productivity as dry wieght was measured at 157.1 g/m and 207.8 g/m for the burn and control respectively. Microtus pennsylvanicus and Clethrionomys rutilus were the two most common small mammals encountered; Microtus xanthognathus, Synaptomys borealis, and Phenacomys intermedius also occured in the area. Populations of M. pennsylvanicus and C. rutilus were high during the summer of 1973; however, M. pennsylvanicus was rare on the control but abundant on the burn, while C. rutilus was rare on the burn but abundant in the control. During the summer of 197^ populations declined, with the result that few voles of any species were caught in the burn while equal numbers of the two species were caught in the control. During the summer of 1973 M. pennsylvanicus showed a positive association to the most productive habitat type in the burn which was avoided by C. rutilus. In the control £• rutilus showed a similar positive association to the most productive habitat type which was avoided by M. pennsylvanicus. In all cases for the high population year of 1973# the two species never overlapped in habitat preference. When populations declined in 197^f "both species showed a strong association for the most productive habitat in the control. This would suggest that during a high population year, an abundant species can exclude competitors from a chosen habitat, but that this dominance decreases as population levels decrease. It is possible that M. pennsylvanicus is a more efficient competitor in a recently burned environment, while C. rutilus assumes this role once non-vascular regrowth becomes extensive.

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Icewine is a sweet dessert wine fermented from the juice of grapes naturally frozen on the vine. The production of Icewine faces many challenges such as sluggish fermentation, which often yields wines with low ethanol, and an accumulation of high concentration of volatile acidity, mainly in the form of acetic acid. This project investigated three new yeast strains as novel starter cultures for Icewine fermentation with particular emphasis on reducing acetic acid production: a naturally occurring strain of S. bayanus/S. pastorianus isolated from Icewine grapes, and two hybrids between S. cerevisiae and S. bayanus, AWRI 1571 and AWRI 1572. These strains were evaluated for sugar consumption patterns and metabolic production of ethanol, glycerol and acetic acid, and were compared to the performance of a standard commercial wine yeast KI-VI116. The ITS rONA region of the two A WRI crosses was also analyzed during fermentations to assess their genomic stability. Icewine fermentations were performed in sterile filtered juice, in the absence of indigenous microflora, and also in unfiltered juice in order to mirror commercial wine making practices. The hybrid A WRI 1572 was found to be a promising candidate as a novel starter culture for Icewine production. I t produced 10.3 % v/v of ethanol in sterile Riesling Icewine fermentations and 11.2 % v/v in the unfiltered ones within a reasonable fermentation time (39 days). Its acetic acid production per gram sugar consumed was approximately 30% lower in comparison with commercial wine yeast K I -V 1116 under both sterile filtered and unfiltered fermentations. The natural isolate S. bayanus/S. pastorianus and AWRI 1571 did not appear to be suitable for commercial Icewine production. They reached the target ethanol concentration of approximately 10 % v/v in 39 day fermentations and also produced less acetic acid as a function of both time and sugar consumed in sterile fermentations compared to KI-V1116. However, in unfiltered fermentations, both of them failed to produce the target concentration of ethanol and accumulated high concentration of acetic acid. Both A WRI crosses displayed higher loss of or reduced copies in ITS rDNA region from the S. bayanus parent compared to the S. cerevisiae parent; however, these genomic losses could not be related to the metabolic profile.

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Neoliberalism is having a significant and global impact on political, social and economic life across spaces. This work illustrates how neoliberalism is attempting to change the ways in which the urban poor - particularly those that participate in street vending - use urban spaces in Lima, Peru. Using municipal policies, newspaper articles and local academic texts I argue that there is a changing marginality in Lima that is being experienced by street vendors, and currently in los canas of Lima. In particular, I discuss formalization, a neoliberal strategy in street vending policy, which is used with eradication and social assistance strategies in attempts to re-regulate street vendors.

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The work to be presented herein illustrates several important facts. First, the synthesis of BIBOL (19), a 1,4-diol derived from the monoterpene camphor has allowed us to demonstrate that oxidative dimerizations of enolates can, and do proceed with nearly complete diastereoselectivity under kinetically controlled conditions. The yield of BIBOL is now 50% on average, with a 10% yield of a second diastereomer, which is likely the result of a non-kinetic hydride reduction, thereby affording the epimeric alcohol, 20, coupled on the exo face of camphor. This implies the production of 60% of a single coupling diastereomer. No other diastereomers from the reduction were observed. The utility of BEBOL has been illustrated in early asymmetric additions of diethylzinc to aryl aldehydes, with e.e.'s as high as 25-30%. '^' To further the oxidative coupling work, the same methodology which gave rise to BIBOL was applied to the chiral pool ketone, menthone. Interestingly, this gave an excellent yield of the a-halohydrin (31), which is the result of a chlorination of menthone. This result clearly indicates the high stereoselectivity of the process regardless of the outcome, and has illustrated an interesting dichotomy between camphor and menthone. The utility of the chlorination product as a precursor other chiral ligands is currently being investigated. > ' Finally, a new series of 1,3-diols as well as a new aminoalcohol have successfully been synthesized from highly diastereoselective aldol/mannich reactions. Early studies have indicated their potential in asymmetric catalysis, while employing pi-stack interactions as a means of controlling enantioselective aldol reactions.

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The fatty acid composition of the total cellular lipids of Choanephora cucurbitarum incubated for 96 hrs on either glucose-ammonium sulfate or malt-weast extract media was determined. The major fatty acids were palmitic, palmitoleic, stearic and linoleic acids. The saturated fatty acid possessing the longest acyl chain was stearate (C 18:0). The presence of glutamic acid (2.0 x 10-1% or 1.36 x la-2M) in either of the above growth media resulted in increase in percent of 1f-linolenic acid, decrease in percent of linoleic ~iCid and appearance of a new series of fatty acid> C ~8 e.g. C ",,,,'V' C2k:O, C26,O. The addition of glutamic acid had no effect on the lipid yield but slightly decreased the degree of unsaturation. Compounds which duplicated the effect of glutamic acid were acetate, malate, citrate, succinate, 0( -ketoglutarate, prOline, -y -aminobutyric acid and glucose (3%) but not aspartic acid or alanine. ~o correlation was found between glutamic acid pool concentration and the presence in the growth medium of those compounds which stimulate long chain fatty acid production. Four hours of incubation with 27 JJ 1-1 glutamate supported the production of long chain fatty acids. This stimulation is inhibited if 272 .u M isophthalic acid is added with 27 AJ M glutamate. But, long chain fatty acids were detected when 27 JJ M eX -ketoglutarate is also present in the incubation mixture. Five hours of incubation with 100 ,Mg/ml of cycloheximide resulted in over 9CY/o inhibition of cytoplasmic :protein synthesise Glutamate (27 .uM) enhanced the synthesis of long chain fatty acids under these conditions. These findings are discussed in an attempt to provide a plausible explanation COmmon to compounds that support the production of long chain fatty acids.

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Film sequels are a pervasive part of film consumption practices and have become an important part of the decision making process for Hollywood studios and producers. This thesis indicates that sequels are not homogenous groups of films, as they are often considered, but offer a variety of story construction and utilize a variety of production methods. Three types of blockbuster sequel sets are identified and discussed in this thesis. The Traditional Blockbuster Sequel Set, as exemplified by Back to the Future (1985, 1989, 1990) films, is the most conventional type of sequel set and capitalizes on the winning formula of the first film in the franchise. The MultiMedia Sequel Set, such as The Matrix (1999,2003) trilogy, allows the user/viewer to experience and consume the story as well as the world of the film through many different media. The Lord a/ the Rings (2001, 2002, 2003) set of films is an illustration of The Saga Sequel Set where plot lines are continuous over the entire franchise thus allowing the viewer to see the entire set as a unified work. The thesis also demonstrates how the blockbuster sequel sets, such as the Pirates a/ the Caribbean (2003, 2006, 2007) franchise, restructure the production process of the Hollywood film industry.

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As a major manufacturing hub in southern Ontario, Hamilton enjoyed considerable economic stability during the twentieth century. However, like most industrial-based cities, Hamilton’s role as a North American manufacturing producer has faded since the 1970’s. This has resulted in dramatic socio-economic impacts, most of which are centered on the inner city. There have been many attempts to revive the core. This includes Hamilton’s most recent urban renewal plans, based upon the principles of Richard Florida’s creative city hypothesis and Ontario’s Places to Grow Act (2005). Common throughout all of Hamilton’s urban renewal initiatives has been the role of the local press. In this thesis I conduct a discourse analysis of media based knowledge production. I show that the local press reproduces creative city discourses as local truths to substantiate and validate a revanchist political agenda. By choosing to celebrate the creative class culture, the local press fails to question its repercussions