889 resultados para Work in groups


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Phenolic compounds are important components of grapes and wines. They have been found to have important roles in grape and wine systems and properties that are beneficial for human health. Vanillin (3-methoxy-4-hydroxybenzaldehyde) is a phenolic compound coming from the oxidative degradation of lignin in oak-barrels during the aging of wine. Vanillin is an important flavour component of wine and its concentration in wine influences significantly the aroma and flavour of wine. The concentration of vanillin in wine is affected by various factors including the presence of metal ions. In this work, by using HPLC, HPLC-MS, and MS technologies, iron (III) cations were found to affect the oxidation of vanillin in a model system of wine, and the product of the oxidation was identified as divanillin. The mechanism of the redox reaction between vanillin and Fe^"^ is thought to follow that of other phenol oxidations. Increasing the concentration of Fe ^ in the model system accelerates divanillin production. The best pH condition for the divanillin production in the system is the range of 3.0 ~ 3.5. Increasing temperature from 20°C to 40°C accelerates the divanillin production. Divanillin was found to exist in three commercial red wines in this work. Keeping the storage temperature cool and decreasing the contact of grapes and wines with iron are two major measures suggested by this work in order to decrease the oxidation of vanillin during the making and aging of wine.

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Thesis (Ph.D.)--Brock University, 2010.

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The inverse relationship between arboreal lichen species richness and sulphur dioxide in ambient air has been thoroughly documented in the literature. Previous work in southern Ontario has shown that lichen bioindication can identify areas of potential concern regarding air quality. The EMAN suite of l i chens was applied in the City of Samia by surveying 458 Sugar Maple trees, in order to test the applicability of lichen bioindication under conditions of high mean S02 levels and high species richness values. The results of the survey were explored using Geographic Information Systems. A spatial relationship between lichen community variables, the Bluewater Bridge and the highway was identified. Lichen species richness, lichen percent cover and Index of Atmospheric Purity values were higher along the bridge and highway. No strong gradients were found between other known pollution sources and no lichen deserts were identified. The most common community grouping consisted of Physcia millegrana Degel, Candelaria concolor (Dicks) B. Stein, Physcia aipolia (Ehrh ex Humb.) Furnrohr; all of which are known nitrophytes. The relationship between substrate pH and lichen species richness was examined. Sites with a known source of anthropogenic chemical contamination were found to have a correlation of l=0.8 between lichen species richness and pH. The inverse was found for sites with no known source of contamination with a correlation of r 2 =-0.72. The findings suggest that species richness may be influenced by altering substrate pH which promotes the growth of nitrophytic species capable of tolerating high S02 levels.

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George Cran was the son of a farmer in the parish of Forgue in Aberdeen Shire, Scotland. He became a member of the church at Huntley, Scotland where his devotion to God inspired him to become a Sunday school teacher. He subsequently became a member of the London Missionary Society. In 1801 he was sent to study at the seminary in Gosport, England where he spent two to three years. His desire was to preach Christ to the “heathens”. Messrs. Ringeltaube, Des Granges and Cran were designated to work in India. No ships for the East India Company would grant passage to missionaries due to the open hostility of the government therefore they set sail from Copenhagen on April 20, 1804 and reached Tranquebar on December 5th, 1805. Cran and Des Granges were designated to supervise the churches in Tinnevelly and they were to begin a mission among the northern Circars. This would have meant that they would have to work in two different places which would have separated them by over 500 miles. The society didn’t seem to be aware of the vast hindrances that the missionaries had to face. Cran and Des Granges decided instead to work in Vizagapatam where they were welcomed by many of the European residents. They conducted English services for which they were paid a monthly salary by the governor. They also conducted services for the natives and opened a school for native children. By November of 1806 a mission house had been built and a “charity” school for Eurasian children was opened. Cran and Des Granges were also diligently studying the native language and they began to translate the Bible into Telugu (spoken by the Hindus who live along the lower basins of the Kistna and Godaveri Rivers). In November of 1808 Cran was almost killed by a fever which left him severely weakened. He was only partially recovered, but accepted an invitation by the general who commanded the local district to accompany him on a journey around the province. The journey proved to be too much for Cran and he died on January 6th, 1809. He is buried at Chicacole, India. He is remembered for his successful work at Vizagapatam and his translation of the Bible. The fact that it was 27 years after the arrival of Cran before a single native was converted attests to the fact that this was a very difficult undertaking. The London Missionary Society was formed in 1795 in England by evangelical Anglicans and nonconformists. It is a non-denominational society and now forms part of the Council for World Mission. with information from The Voice of God to the Churches a Sermon on the Death of George Cran, Augustus Des Granges and Jonathan Brain by David Bogue and The History of the London Missionary Society 1795-1895 by Richard Lovett