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Preventive maintenance of frequency converters has been based on pre-planned replace-ment of wearing or ageing components. Exchange intervals follow component life-time expectations which are based on empirical knowledge or schedules defined by manufac-turer. However, the lifetime of a component can vary significantly, because drives are used in very different operating environments and applications. The main objective of the research was to provide information on methods, i.e. how in-verter's operating condition can be measured reliably under field conditions. At first, the research focused on critical components such as current transducers, IGBTs and DC link capacitor bank, because these aging have already been identified. Of these, the DC link capacitor measurement method was selected for closer examination. With this method, the total capacitance and its total series resistance can be measured. The suitability of the measuring procedure was estimated on the basis of practical measurements. The research was made by using so called triangulation method, including a literature review, simulations and practical measurements. Based on the results, the new measu-rement method seems suitable with some reservations to practical measurements. How-ever, the measuring method should be further developed in order to improve its reliability.

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Collectionneur : Lesouëf, Auguste (1829-1906)

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Dr. Deeks and Dr. Gibson admiring the Brock Unviersity sign at the Glenrdige Campus. Renovations to the old refigerator factory were only just underway at this time.

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Dr. Deeks and Dr. Gibson touring the recently acquired Decew Campus site along a stretch of Merrittville Highway in early 1964. The Sanatorium can be seen in the background.

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Dr. Deeks and Dr. Gibson examining the sign at the Decew Campus site along the stretch of Merrittville Highway just north of St. Davids Road. This photo was taken in March of 1964.

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Members of Brock University's Founders Committee and the Ontario Advisory Committee on Univesity Affairs tour the Decew site along with Premier John Robarts on June 5, 1963. Premier Robarts had just announced provincial assistance totalling $393,000 for the Brock University project. Pictured here from left to right are Dr. Deeks, Brock University Vice President; Premier Robarts; and James Allan, Provincial Treasurer.

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Fifty kHz rat vocalizations are theorized to reflect a positive affective state, and index the reward value of stimuli (Knutson, Burgdorf & Panksepp, 2002; Panksepp & Burgdorf, 2003; Brudzynski,2005). Previous studies have identified the neurochemical substrate of this behaviour to be dependent on dopaminergic activity at the nucleus accumbens shell (Burgdorf, Knutson, Panksepp & Ikemoto, 2001; Thompson, Leonard & Brudzynski, 2006). The utilization of d-amphetamine (a non-selective dopamine agonist) in these studies does not address the specific dopamine receptor types involved. The present study aims to identify the role of the D2- like family of receptors in the nucleus accumbens shell in the production of 50 kHz vocalizations in adult rats. Single injections of quinpirole in a saline vehicle were administered to the nucleus accumbens shell of 57 rats, and the number of 50 kHz vocalizations were recorded. An inverted V-shaped relationship was found between quinpirole dose (0.5 ~g, 3 ~g, 6 ~g, 1 0 ~g and 20 ~g, all in 0.2~1 saline) and the mean number of 50 kHz calls produced. Quinpirole successfully elicited significantly more 50 kHz calls than did a saline control at the 6 ~g dose, as did 7 ~g/0.2 ~l of d-amphetamine injections into the same brain site. To test whether a selective D2 antagonist could reverse elicited 50 kHz calling, double injections were given that used either saline or raclopride as a pretreatment before quinpirole injections. Saline followed by 6 ~g/0.2 ~l of quinpirole elicited significantly more 50 kHz vocalizations than did a double injection of saline, while pretreatment with an equimolar dose of raclopride reduced elicited calls to control levels. Raclopride was also used as a pretreatment of 7 ~g/0.2 ~l d-amphetamine, which elicited significantly fewer 50 kHz vocalizations than saline followed by amphetamine, replicating the finding of Thompson, Leonard & Brudzynski (2006).Subcutaneous injections of 0.5 mg/kg and 1.5 mg/kg of quinpirole produced a similar number of 50 kHz vocalizations as subcutaneous injection of saline. Wider dose ranges may be explored in fiiture research. Thus, direct activation of the Da-like receptors in the nucleus accumbens shell was sufficient to elicit 50 kHz vocalizations in adult rats, an effect which was reversed with selective local antagonism of Da-like receptors. The Da-like receptor family also appears necessary for pharmacological activation of 50 kHz calling, as d-amphetamine was no longer able to effectively elicit these vocalizations from the nucleus accumbens shell when the Da-receptor family was antagonized with raclopride. The acoustic parameters of elicited vocalizations remained typical of rat 50 kHz calls. Detailed analyses of the acoustic characteristics of elicited calls indicated significant increases in call duration and peak frequency across drug injection groups, particularly among quinpirole dose groups. The implications of these findings are not yet clear, but may represent an important direction for future research into the coding of semiotic content into affective signals in rats.

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Euclidean distance matrix analysis (EDMA) methods are used to distinguish whether or not significant difference exists between conformational samples of antibody complementarity determining region (CDR) loops, isolated LI loop and LI in three-loop assembly (LI, L3 and H3) obtained from Monte Carlo simulation. After the significant difference is detected, the specific inter-Ca distance which contributes to the difference is identified using EDMA.The estimated and improved mean forms of the conformational samples of isolated LI loop and LI loop in three-loop assembly, CDR loops of antibody binding site, are described using EDMA and distance geometry (DGEOM). To the best of our knowledge, it is the first time the EDMA methods are used to analyze conformational samples of molecules obtained from Monte Carlo simulations. Therefore, validations of the EDMA methods using both positive control and negative control tests for the conformational samples of isolated LI loop and LI in three-loop assembly must be done. The EDMA-I bootstrap null hypothesis tests showed false positive results for the comparison of six samples of the isolated LI loop and true positive results for comparison of conformational samples of isolated LI loop and LI in three-loop assembly. The bootstrap confidence interval tests revealed true negative results for comparisons of six samples of the isolated LI loop, and false negative results for the conformational comparisons between isolated LI loop and LI in three-loop assembly. Different conformational sample sizes are further explored by combining the samples of isolated LI loop to increase the sample size, or by clustering the sample using self-organizing map (SOM) to narrow the conformational distribution of the samples being comparedmolecular conformations. However, there is no improvement made for both bootstrap null hypothesis and confidence interval tests. These results show that more work is required before EDMA methods can be used reliably as a method for comparison of samples obtained by Monte Carlo simulations.

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The spatial limits of the active site in the benzylic hydroxylase enzyme of the fungus Mortierella isabellina were investigated. Several molecular probes were used in incubation experiments to determine the acceptability of each compound by this enzyme. The yields of benzylic alcohols provided information on the acceptability of the particular compound into the active site, and the enantiomeric excess values provided information on the "fit" of acceptable substrates. Measurements of the molecular models were made using Cambridge Scientific Computing Inc. CSC Chem 3D Plus modeling program. i The dimensional limits of the aromatic binding pocket of the benzylic hydroxylase were tested using suitably substituted ethyl benzenes. Both the depth (para substituted substrates) and width (ortho and meta substituted substrates) of this region were investigated, with results demonstrating absolute spatial limits in both directions in the plane of the aromatic ring of 7.3 Angstroms for the depth and 7.1 Angstroms for the width. A minimum requirement for the height of this region has also been established at 6.2 Angstroms. The region containing the active oxygen species was also investigated, using a series of alkylphenylmethanes and fused ring systems in indan, 1,2,3,4-tetrahydronaphthalene and benzocycloheptene substrates. A maximum distance of 6.9 Angstroms (including the 1.5 Angstroms from the phenyl substituent to the active center of the heme prosthetic group of the enzyme) has been established extending directly in ii front of the aromatic binding pocket. The other dimensions in this region of the benzylic hydroxylase active site will require further investigation to establish maximum allowable values. An explanation of the stereochemical distributions in the obtained products has also been put forth that correlates well with the experimental observations.

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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.

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The Women's Literary Club of St. Catharines was founded in 1892 by a local author, Emma Harvey (Mrs. J.G.) Currie (1829-1913) and held its last official meeting on February 19, 1994. The Club developed, flourished and eventually waned. After more than one hundred successful years, the last members deposited the Club's archives at Brock University for the benefit of researchers, scholars and the larger community. The ‘object of the Club’ was established as “the promotion of literary pursuits.” The Club was a non-profit social organization composed of predominantly white, upper middle class women from the St. Catharines and surrounding areas. Club meetings were traditionally held fortnightly from March to December each year. The last meeting of the year was a celebration of their Club anniversary. The early meetings of the Club include papers presented and music performed by Club members. The literary pursuits that would dominate the agendas for the entire life of the Club reflected an interest in selected authors, national and local history, classical history, musical performances and current cultural and newsworthy events. For example in 1893 a typical meeting agendas would contain papers on Henry Wadsworth Longfellow, Hawaii, Brook Farm, Miss Louisa May Alcott and “Education of Women 100 years Ago.” Within the first year of the Club’s existence, detailed minute books became the norm and an annual agenda or program developed. The WLC collection contains a near complete set of meeting minutes from 1892 until 1995 and a comprehensive collection of yearly programs from 1983-1967 which members took great care to publish each year. Mrs. Currie brought together a group of women with a shared interest in literature and history, who wanted to pursue that interest in a formal and structured manner. She was well educated and influenced at an early age by her tutor and mentor William Kirby, local historian, writer and newspaper editor from Niagara-on-the-Lake. While Currie’s private education influenced her love of literature and history, the Club movement of the 1890’s offered a more public forum for her to share knowledge and learning with other women. Mrs. Currie was the wife of St. Catharines lawyer, James G. Currie, who also served as a Member of Parliament for the county of Lincoln. Mrs. W.H. McClive, who was also married to a St. Catharines lawyer, worked closely with Currie and they began research into the possibility of a literary Club in St. Catharines. Currie corresponded with a variety of literary Clubs across North America before she and Mrs.McClive tagged onto the momentum of the Club movement and published “A Clarion call for Women of St. Catharines To Form a Literary Club” in the local paper The St. Catharines Evening Journal. in 1892 and asked like Clubs to publish the news of their new Club. The early years of the WLC set the foundation of how the Club meetings and events would unfold for the next 80 plus years. Photos and minutes from the first ten years reveal an excitement and interest in organized Club outings. One particular event, an annual pilgrimage to the homestead of Laura Secord, became a yearly celebration for the Club. Club President, Mrs. Currie’s own personal work on Laura Secord amplified the Club’s interest in the ‘heroine of 1812’ and she allocated the profits from her publication on Secord in order to create a commemorative plaque/monument in the name of Laura Secord. The Club celebrated this event with a regular pilgrimage to this site. The connection felt by Club members and this memorial would continue until the Club’s last meetings. The majority of members in the early years were of the upper middle classes in the growing city of St. Catharines. Many of the charter members were the wives of merchants, business men, lawyers, doctors, even a hatter. Furthermore, the position of president was most often held by a woman with a comprehensive list of interests. This is particularly the case in Isabel Brighty McComb (1876-1941). Brighty who became a member in 1903, became Club president in 1932 and stayed in her post until her death in 1941. Similar to Mrs. Currie, Brighty was a local historian and published 2 booklets on local history. Her obituary indicates her position in the community as an author and involved community member committed to lifetime memberships in the Imperial Order of Daughters of Empire, I.O.D.E., the National Organization of Women, N.O.W. and the United Empire Loyalist Society, as well as the WLC. She was a locally known ‘teacher of elocution’ and a devoted researcher of Upper Canadian history. In a Club scrapbook dedicated to her, the biographical sketch illustrates the professionalism surrounding Brighty. There is very little personal history mentioned and the focus is on her literary works, her published essay, booklets and poetry. This professional focus, evident in both her obituary and the scrapbook, illustrate the diversity of these women, especially in their roles outside of the home. The WLC collection contains a vast array of essay, lectures clippings and scrapbooks from past meetings. Organized predominantly by topic or author, the folders and scrapbooks offer a substantial amount of research opportunity in the literary history of Canada. The dates, scope of topics and authors covered offer historians an exciting opportunity to examine the consumption of particular literary trends, artists and topics within the context of a midsized industrial city in English Canada. This is especially important because the agenda adhered to by the Club was bent on promoting, discussing and reviewing predominantly Canadian material. By connecting when and what these women were studying, scholars many gain a better understanding of the broader consumption and appreciation of literary and social trends of Canadian women outside of publishing and institutional records. Furthermore, because the agendas were set by and for these women, outside of the constructs of an institutionalized canon or agenda, they offer a fresh and on the ground examination of literary consumption over an extensive length of time.

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The proce-ss ofoxygenic photosynthesis is vital to life on Earth. the central event in photosynthesis is light induced electron transfer that converts light into energy for growth. Ofparticular significance is the membrane bound multisubunit protein known as Photosystem I (PSI). PSI is a reaction centre that is responsible for the transfer of electrons across the membrane to reduce NADP+ to NADPH. The recent publication ofa high resolution X-ray structure of PSI has shown new information about the structure, in particular the electron transfer cofactors, which allows us to study it in more detail. In PSI, the secondary acceptor is crucial for forward electron transfer. In this thesis, the effect of removing the native acceptor phylloquinone and replacing it with a series of structurally related quinones was investigated via transient electron paramagnetic resonance (EPR) experiments. The orientation of non native quinones in the binding site and their ability to function in the electron transfer process was determined. It was found that PSI will readily accept alkyl naphthoquinones and anthraquinone. Q band EPR experiments revealed that the non-native quinones are incorporated into the binding site with the same orientation of the headgroup as in the native system. X band EPR spectra and deuteration experiments indicate that monosubstituted naphthoquinones are bound to the Al site with their side group in the position occupied by the methyl group in native PSI (meta to the hydrogen bonded carbonyl oxygen). X band EPR experiments show that 2, 3- disubstituted methyl naphthoquinones are also incorporated into the Al site in the same orientation as phylloquinone, even with the presence of a halogen- or sulfur-containing side chain in the position normally occupied by the phytyl tail ofphylloquinone. The exception to this is 2-bromo-3-methyl --.- _. -. - -- - - 4 _._ _ _ - _ _ naphthoquinone which has a poorly resolved spectrum, making determination of the orientation difficuh. All of the non-native quinones studied act as efficient electron acceptors. However, forward electron transfer past the quinone could only be demonstrated for anthraquinone, which has a more negative midpoint potential than phylloquinone. In the case of anthraquinone, an increased rate of forward electron transfer compared to native PSI was found. From these results we can conclude that the rate ofelectron transfer from Al to Fx in native PSI lies in the normal region ofthe Marcus Curve.

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Municipalities that engage in recreation planning have the potential to use their resources more effectively. However, successful planning means getting the plan off the shelf and implemented. This study investigated the factors that influenced municipal recreation plan implementation in three municipalities. Interviews were conducted with eleven key informants (recreation directors, planning consultants, a city councillor, and members of plan steering committees). The findings of this study suggested that because the implementation of recreation plans occurs in a highly political environment, recreation professionals will need effective strategies to get their plans implemented and that implementation can be facilitated by developing or expanding strategies that: (l) build the power of the recreation department within the municipal government structure; (2) build support for recreation within the local community; and (3) build the political and organizational capacity in the recreation department.