The relationship between stem-form, stand-closure and site -conditions : the influence of environmental conditions on tree allometry and forest structure in west-central Alberta

Changes in the configuration of a tree stern result insignificant differences in its total volume and in the proportion of that volume that is merchantable timber. Tree allometry, as represented by stem-fo~, is the result of the vertical force of gravity and the horizontal force of wind. The effect of wind force is demonstrated in the relationship between stem-form, standclosure and site-conditions. An increase in wind force on the individual tree due to a decrease in stand density should produce a more tapered tree. The density of the stand is determined by the conditions that the trees are growing under. The ability of the tree to respond to increased wind force may also be a function of these conditions . This stem-form/stand-closure/site-conditions relationship was examined using a pre-existing database from westcentral Alberta. This database consisted of environmental, vegetation, soils and timber data covering a wide range of sites. There were 653 sample trees with 82 variables that formed the basis of the analysis. There were eight tree species consisting of Pinus contorta, Picea mariana, Picea engelmannii x glauca, Abies lasiocarpa, Larix laricina, Populus tremuloides, Betula papyrifera and Populus balsamifera plus a comprehensive all-species data set. As the actual conformation of the stern is very individual, stem-fo~was represented by the diameter at breast height to total height r~tio. The four stand-closure variables, crown closure, total basal area, total volume and total number of stems were reduced to total basal area and total number of stems utilizing a bivariate correlation matrix by species. Site-conditions were subdivided into macro, meso and micro variables and reduced in number 3 using cross-tabulations, bivariate correlation and principal components analysis as screening tools. The stem-fo~/stand-closure relationship was examined using bivariate correlation coefficients for stem-fo~ with total number of stems and stem-fo~ with total basal area. The stem-fo~/site-conditions and the stand-closure/site- conditions relationships were examined using multiple correlation coefficients. The stem-form/stand-closure/site-conditions relationship was examined using multiple correlation coefficients in separate analyses for both total number of stems and total basal area. An increase in stand-closure produced a decrease in stem-form for both total number of stems and total basal area for most species. There was a significant relationship between stem-form and site-conditions and between stand-closure and site-conditions for both total number of stems and total basal area for most species. There was a significant relationship between the stemform and site-conditions, including the stand-closure, for most species; total number of stems was involved independently of the site-conditions in the prediction of stem-form and total basal area was not. Larix laricina and Betula papyrifera were the exceptions to the trends observed with most species. The influence of both stand-closure (total number of stems in particular) and site-conditions (elevation in particular) suggest that forest management practices should include these- ecological parameters in determining appropriate restocking levels.

The versatility and utilization of phosphorus based compounds in classic carbon-carbon bond forming and esterification reactions

The phosphonium salt room temperature ionic liquid tetradecyltrihexylphosphonium chloride (THPC) has been employed as an efficient reusable media for the palladium catalyzed Suzuki cross-coupling reaction of aryl halides, including aryl chlorides, under mild conditions. The cross-coupling reactions were found to proceed in THPC containing small amounts ofwater and toluene (single phase) using potassium phosphate and 1% Pd2(dba)3'CHCI3. Variously substituted iodobenzenes, including electron rich derivatives, reacted efficiently in THPC with a variety of arylboronic acids and were all complete within 1 hour at 50°C. The corresponding aryl bromides also reacted under these conditions with the addition of a catalytic amount of triphenylphosphine that allowed for complete conversion and high isolated yields. The reactions involving aryl chlorides were considerably slower, although the addition of triphenylphosphine and heating at 70°C allowed high conversion of electron deficient derivatives. Addition of water and hexane to the reaction products results in a triphasic system, from which the catalyst was then recycled by removing the top (hexanes) and bottom (aqueous) layers and adding the reagents to the ionic liquid which was heated again at 50°C; resulting in complete turnover of iodobenzene. Repetition of this procedure gave the biphenyl product in 82-97% yield (repeated five times) for both the initial and recycled reaction sequences. IL ESTERIFICATIONREACTION A new class oftrialkylphosphorane has been prepared through reaction of a trialkylphosphine with 2-chlorodimethylmalonate in the presence oftriethylamine. These new reagents promote the condensation reaction of carboxylic acids with alcohols to provide esters along with trialkylphosphine oxide and dimethylmalonate. The condensation reaction of chiral secondary alcohols can be controlled to give either high levels of inversion or retention through a subtle interplay involving basicity of the reaction media, solvent, and tuning the electronic and steric nature of the carboxylic acid and stenc nature of the phosphorane employed. A coherent mechanism is postulated to explain these observations involving reaction via an initial acyloxyphosphonium ion.

Modifications to the Suzuki reaction and mechanistic insights on the NBS mediated cleavage of benzylidene acetals /

One of the most challenging tasks for a synthetic organic chemist today, is the development of chemo, regio, and stereoselective methodologies toward the total synthesis of macromolecules. r . The objective of my thesis was to develop methodologies towards this end. The first part of my project was to develop highly functionalized chirons from D-glucose, a cheap, chiral starting material, to be utilized in this capacity. The second part of the project dealt with modifying the carbon-carbon bond forming Suzuki reaction, which is utilized quite often as a means of combining molecular sub units in total synthesis applications. As previously stated the first area of the project was to develop high value chirons from D-glucose, but the mechanism of their formation was also investigated. The free radical initiated oxidative fragmentation of benzylidene acetals was investigated through the use of several test-case substrates in order to unravel the possible mechanistic pathways. This was performed by reacting the different acetals with N-bromosuccinimide and benzoyl peroxide in chlorobenzene at 70^C in all cases. Of the three mechanistic pathways discussed in the literature, it was determined, from the various reaction products obtained, that the fragmentation of the initial benzylic radical does not occur spontaneously but rather, oxidation proceeds to give the benzyl bromide, which then fragments via a polar pathway. It was also discovered that the regioselectivity of the fragmentation step could be altered through incorporation of an allylic system into the benzylidene acetal. This allows for the acquisition of a new set of densely functionalized. chiral, valuable synthetic intermediates in only a few steps and in high yields from a-Dglucose. The second part of the project was the utilization of the phosphonium salt room temperature ionic liquid tetradecyltrihexylphosphonium chloride (THPC) as an efficient reusable medium for the palladium catalyzed Suzuki cross-coupling reaction of aryl halides, including aryl chlorides, under mild conditions. The cross-coupling reactions were found to proceed in THPC containing small amounts of water and toluene using potassium phosphate and 1% Pd2(dba)3. Variously substituted iodobenzenes, including electron rich derivatives, reacted efficiently in THPC with a variety of arylboronic acids and afforded complete conversion within 1 hour at 50 ^C. The corresponding aryl bromides also reacted under these conditions with the addition of a catalytic amount of triphenylphosphine that allowed for complete conversion and high isolated yields. The reactions involving aryl chlorides were considerably slower, although the addition of triphenylphosphine and heating at 70 ^C allowed high conversion of electron deficient derivatives. Addition of water and hexane to the reaction products results in a triphasic system in which the top hexane phase contained the biaryl products, the palladium catalyst remained fully dissolved in the central THPC layer, while the inorganic salts were extracted into the lower aqueous phase. The catalyst was then recycled by removing the top and bottom layers and adding the reagents to the ionic liquid which was heated again at 50 ^C; resulting in complete turnover of iodobenzene. Repetition of this procedure gave the biphenyl product in 82-97% yield (repeated five times) for both the initial and recycled reaction sequences.

Examining the Nature of Published Research About Mentoring in Higher Education

The various forms of mentoring relationships in higher education have all proven to be valuable, offering numerous benefits to mentors and protégés. Research into mentoring provides critical insight into aspects of these relationships, which can be used to advance theoretical and practical understandings of the topic. However, little is known about the methodological characteristics of the mentoring research itself. Using descriptive quantitative content analysis, I examined five years of articles published in five scholarly journals to determine the prevalence of research about mentoring in higher education. Not surprisingly, the prevalence of these articles differed significantly among journals in higher education (1.07% to 3.13%) compared to the considerably higher prevalence rate of 53.15% for the mentoring journal, Mentoring & Tutoring [χ2 (4, N = 82) = 143.98, p < .01]. I also report findings related to the prevalence of different empirical research traditions, research designs, and data sources, as well as various populations, such as faculty members or graduate students who serve as mentors or protégés. Given the limited number of mentoring articles published in higher education journals, I was unable to compare methodological characteristics across journals. Implications for theory, research, and practice in the area of mentoring in higher education are also suggested. Understanding the methodological characteristics of the current literature allows researchers to tailor their current studies by either continuing with existing trends in methodological approaches or seeking opportunities to incorporate under-utilized research traditions, designs, or data sources, with the aim of continuing to improve mentoring knowledge and outcomes.

HG 82.50-82.65

Dark brown sediment with well dispersed clasts ranging from small to medium in size. Clast shape ranges from sub-angular to sub-rounded. Lineations can commonly be seen throughout the sample. Comet structures can also be seen in minor amounts.

Barnes Wines, Limited By-Law no. 82

A by-law "to fix the remuneration and expense allowances of directors". It reads "Be it enacted as a By-law of Barnes Wines Limited: 1. That each Director of the Company be paid the sum of Seventy-five ($75,00) Dollars annually in respect of general services rendered by the Director in his capacity as Director, such remuneration to accrue from the date of his election or appointment as a Director. 2. That each Director shall be paid and allowed travelling and other expenses properly incurred in connection with the affairs of the Company. 3. That this provision shall be and remain in force and effect in the fiscal years of the Company, 1971 to 1973 both inclusive. Enacted this 8th day of February, 1971."

Barnes Wines, Limited By-Law No. 87

The By-Law reads: "Being a By-Law to fix the remunerations and expense allowances of a director. Be it a and it is hereby enacted as a By-Law of the Company as follows: By-Law No. 87 that By-Law No. 82 be and it is hereby repealed."