Reliability of a new measure of motoneuron excitability

Objectlve:--This study examined the intraclass reliability· of different measures of the excitability of the Hoffmann reflex, derived from stimulus-response curves. The slope of the regression line of the H-reflex stimulus-response curve advocated by Funase et al. (1994) was also compared to the peak of the first derivative of the H-reflex stimulus-response curve (dHIdVmax), a new measure introduced in this investigation. A secondary purpose was to explore the possibility of mood as a covariate when measuring excitability of the H-reflex arc. Methods: The H-reflex amplitude at a stimulus intensity corresponding to 5% of the maximum M-wave (Mmax) is an established measure that was used as an additional basis of comparison. The H-reflex was elicited in the soleus for 24 subjects (12 males and 12 females) on five separate days. Vibration was applied to the Achilles tendon prior to stimulation to test the sensitivity of the measures on test day four. The means of five evoked potentials at each gradually increasing intensity, from below H-reflex threshold to above Mmax, were used to create both the H-reflex and M-wave stimulus response curves for each subject across test days. The mood of the subjects was assessed using the Subjective Exercise Experience Scale (SEES) prior to the stimulation protocol each day. Results: There was a modest decrease in all H-reflex measures from the first to third test day, but it was non-significant (P's>0.05). All measures of the H-reflex exhibited a profound reduction following vibration on test day four, and then returned to baseline levels on test day five (P's<0.05). The intraclass correlation coefficient (ICC) for H-reflex amplitude at 5% of Mmax was 0.85. The ICC for the slope of the regression line was 0.79 while it was 0.89 for dH/dVmax. Maximum M-wave amplitude had an ICC of 0.96 attesting to careful methodological controls. The SEES subscales of fatigue and psychological well-being remained unchanged IV across the five days. The psychological distress subscale (PO.05). Conclusions: The peak of the first derivative of the H-reflex stimulus-response curve (dH/dVmax) was shown to have comparable reliability and sensitivity to other more established measures of excitability. Psychological distress and the amplitude of the H-reflex at 5% Mmax follow similar trends across days, however there was no significant correlation between the two measures. Significance: The proposed method appears to be a more robust measure ofH-reflex excitability than the other methods tested. As such it would be an advantageous method to apply in clinical and investigative settings. Additionally, the results suggest that the relationship between psychological distress and H-reflex amplitude should be investigated further.

Understanding value congruence : a sport organization case study

With the recent growth in cultural complexity, many organizations are faced with increasingly diverse employee pools. Gaining a greater understanding of the values that employees possess is the first step in effectively satisfying their needs and achieving a more productive workforce (lung & Avolio, 2000). Values playa significant role in influencing individual behaviours. It is therefore necessary to assess the qualities of employee value systems and directly link them to the values of the organization. The importance of values and value congruence has been emphasized by many organizational behaviour researchers (cf. Adkins & Caldwell, 2004; Erdogan, Kraimer, & Liden, 2004; Jung & Avolio, 2000; Rokeach, 1973); however the emphasis on value studies remains fairly stagnant within the sport industry (Amis, Slack, & Hinings, 2002). In order to examine the realities that were constructed by the participants in this study a holistic view of the impact of values within a specific sport organization were provided. The purpose of this case study was to examine organizational and employee values to understand the effects of values and value congruence on employee behaviours within the context of a large Canadian sport organization. A mUltiple methods case study approach was adopted in order to fully serve the purpose and provide a comprehensive view of the organization being examined. Document analysis, observations, surveys, as well as semi-structured interviews were conducted. The process allowed for triangulation and confirmability of the findings. Each method functioned to create an overarching understanding of the values and value congruence within this organization. The analysis of the findings was divided into qualitative and quantitative sections. The qualitative documents were analyzed twice, once manually by the researcher and once via AtIas.ti Version 4 (1998). The a priori and emergent coding that took place was based on triangulating the findings and uncovering common themes throughout the data. The Rokeach Value Survey (1973) that was incorporated into the survey design of the study was analyzed using descriptive statistics, as well as Mann-Whitney U, and Kruskal Wallis formulas. These were deemed appropriate for analysis given the non-parametric nature of the survey instrument (Kinnear & Gray, 2004). The quantitative survey served to help define the values and value congruence that was then holistically examined through the qualitative interviews, document analyses, and observations. The results of the study indicated incongruent value levels between employees and those stated or perceived as the organization's values. Each finding demonstrated that varying levels of congruence may have diverse affects on individual behaviours. These behaviours range from production levels to interactions with fellow employees to turnover. In addition to the findings pertaining to the research questions, a number of other key issues were uncovered regarding departmentalization, communication, and board relations. Each has contributed to a greater understanding of the organization and has created direction for further research within this area of study.

Epidemiology and phylogenetic analysis of West Nile virus in Ontario, Canada, 2002-2003 /

Since the discovery of West Nile (WN) virus in the Western Hemisphere many surveillance programs have been implemented to monitor the epidemiology and genetic variation of WN virus in North America. This project was based on the WN virus Adult Mosquito Identification and Diagnostic Program conducted at Brock University for Ontario, Canada, during the 2002 and 2003 transmission seasons. There are three sections to this thesis. The first section investigated which mosquito species carry WN virus in Ontario, Canada throughout the 2002-2003 transmission seasons. It was found that from the 2002 data, eight mosquito species were detected with WN virus (Aedes vexans, Anopheles punctipennis, Coquilleltidia perlurbans, Culex salinarius, Cx. pipiens, Cx. resluans, Ochlerolalus Irivillalus and Och. Iriserialus) and 7.19% of the total mosquito pools tested were found to be WN virus positive (129 positive poolsll, 793 total pools tested). In 2003, WN virus was detected in only five mosquito species (Ae. vexans, Cx. salinarius, Och. Iriserialus, Cx. pipiens and Cx. resluans) and 1.42% of the total mosquito pools tested were WN virus positive (101 positive poolsl7,1 01 total pools tested). WN virus positive mosquito pools were detected 3-4 weeks earlier in 2002 compared to 2003 data. The second section investigated the actual infection rate (IR) of clearly identified Cx. pipiens and Cx. resluans from the 2002 outbreak. It was found that significantly more ex. resluans were infected with WN virus compared to ex. pipiens. The third section investigated the degree of variability of the WN virus genome. A 879 nucleotide section of the WN virus genome was amplified from 21 American Crows and 20 adult female mosquitoes from Ontario, Canada, and compared to the homologous region of the original New York 1999 Chilean Flamingo sequence (NY99FL). Seventy-two nucleotides from Ontario WN virus sequences showed variability compared to NY99FL with 10 synapotypic changes. Phylogenetic analysis revealed a close relationship between Ontario and US WN virus sequences.

Engineering an improved adenovirus packaging cell line

Recombinant human adenovirus (Ad) vectors are being extensively explored for their use in gene therapy and recombinant vaccines. Ad vectors are attractive for many reasons, including the fact that (1) they are relatively safe, based on their use as live oral vaccines, (2) they can accept large transgene inserts, (3) they can infect dividing and postmitotic cells, and (4) they can be produced to high titers. However, there are also a number of major problems associated with Ad vectors, including transient foreign gene expression due to host cellular immune responses, problems with humoral immunity, and the creation of replication competent adenoviruses (RCA). Most Ad vectors contain deletions in the E1 region that allow for insertion of a transgene. However, the E1 gene products are required for replication and thus must be supplied in trans by a helper ceillille that will allow for the growth and packaging of the defective virus. For this purpose the 293 cell line (Graham et al., 1977) is used most often; however, homologous recombination between the vector and the cell line often results in the generation of RCA. The presence of RCA in batches of adenoviral vectors for clinical use is a safety risk because tlley . may result in the mobilization and spread of the replication-defective vector viruses, and in significant tissue damage and pathogenicity. The present research focused on the alteration of the 293 cell line such that RCA formation can be eliminated. The strategy to modify the 293 cells involved the removal of the first 380 bp of the adenovirus genome through the process of homologous recombination. The first step towards this goal involved identifying and cloning the left-end cellular-viral jUl1ction from 293 cells to assemble sequences required for homologous recombination. Polymerase chain reaction (PCR) was performed to clone the junction, and the clone was verified through sequencing. The plasn1id PAM2 was then constructed, which served as the targeting cassette used to modify the 293 cells. The cassette consisted of (1) the cellular-viral junction as the left-end region of homology, (2) the neo gene to use for positive selection upon tranfection into 293 cells, (3) the adenoviral genome from bp 380 to bp 3438 as the right-end region of homology, and (4) the HSV-tk gene to use for negative selection. The plasmid PAM2 was linearized to produce a double strand break outside the region of homology, and transfected into 293 cells using the calcium-phosphate technique. Cells were first selected for their resistance to the drug G418, and subsequently for their resistance to the drug Gancyclovir (GANC). From 17 transfections, 100 pools of G418f and GANCf cells were picked using cloning lings and expanded for screening. Genomic DNA was isolated from the pools and screened for the presence of the 380 bps using PCR. Ten of the most promising pools were diluted to single cells and expanded in order to isolate homogeneous cell lines. From these, an additional 100 G41Sf and GANef foci were screened. These preliminary screening results appear promising for the detection of the desired cell line. Future work would include further cloning and purification of the promising cell lines that have potentially undergone homologous recombination, in order to isolate a homogeneous cell line of interest.

Upper Lakes Shipping Ltd. fonds 1955-1990, n.d. (non-inclusive)

In March 1931, Captain Bruce Angus was sent to Sarnia by Gordon C. Leitch, general manager of Toronto Elevators. He was sent to inspect the Sarnian to ensure it was still seaworthy. Leitch was a savvy business man, who had been active in the business community for a number of years. Leitch began his career with a partner in the lumber business. When that went under he moved into graineries and worked for the Winnipeg Wheat Pool for 12 years. After Winnipeg he moved to Toronto, which was closer to his home town of Ridgetown, Ontario. In Toronto Leitch became manager of the Toronto branch of the Canadian Wheat Pool. While managing the wheat pools in Toronto Leitch became aware of huge costs associated with shipping the grains from the praries into the Toronto area. He felt that there was no need for such costs and decided to do something to make them better and cheaper for the business. Originally the grain was loaded onto Lakers that would bring the grain from the praries to Lake Huron and Georgian Bay. It was stored there until needed by the Toronto graineries and then hauled across land by either truck or train. The land journey was the most expensive and the one which Leitch wanted to eliminate. This was a fine plan except for 2 obstacles that were quickly overcome. First of all the Welland canals were not large enough to accommodate the large carriers that were bringing in the grain. This was changing as the expansion and widening of the canals was already underway. The second issue was the lack of storage in Toronto for the grain. The grain elevators had been destroyed by fire in the late 1880s and never replaced. Leitch propsed his company built its own storage elevators along the water front to allow not only for easier access to the grain, and more timely production of products. The elevators would aslo create a reduction in shipping costs and an overall more competitoive price for the customers of the grainery. The company refused, so Leitch went elsewhere to friends and contacts within the grain industry. The elevators were built and Leitch quit his job with the Canadian Wheat Pool and became the general manager of the elevators. Although the elevators were built and ready for storage the next issue was filling them. None of the carriers wanted to do business with Leitch because the competition in Georgian Bay threatened to cancel their contracts if they did. Leitch saw no way around this, but to provide his own transportation. This is when he sent Captain Bruce Angus to scout out potential ships. The ship was purchased for $37,000 and after another $30,000 was spent to fix it up, it was ready for business. The need for transportation and the finding of a seaworthy ship, lead to the beginnings of the Northland Steamship Company. The Sarnian proved to not be enough for the business underway. Leitch decided another ship was necessary. He joined forces with James Norris the owner of the Norris Grain Company. He proposed they join forces to create a more economical means of transportating their products.

Aspects of spatial and habitat ecology of multiple Anopheles species (Diptera: Culicidae): malaria vectors in the highlands and foothills of Ecuador

The resurgence of malaria in highland regions of Africa, Oceania and recently in South America underlines the importance of the study of the ecology of highland mosquito vectors of malaria. Since the incidence of malaria is limited by the distribution of its vectors, the purpose of this PhD thesis was to examine aspects of the ecology of Anopheles mosquitoes in the Andes of Ecuador, South America. A historical literature and archival data review (Chapter 2) indicated that Anopheles pseudopunctipennis transmitted malaria in highland valleys of Ecuador prior to 1950, although it was eliminated through habitat removal and the use of chemical insecticides. Other anopheline species were previously limited to low-altitude regions, except in a few unconfirmed cases. A thorough larval collection effort (n=438 attempted collection sites) in all road-accessible parts of Ecuador except for the lowland Amazon basin was undertaken between 2008 - 2010 (Chapter 3). Larvae were identified morphologically and using molecular techniques (mitochondrial COl gene), and distribution maps indicated that all five species collected (Anopheles albimanus, An. pseudopunctipennis, Anopheles punctimacula, Anopheles oswaldoi s.l. and Anopheles eiseni) were more widespread throughout highland regions than previously recorded during the 1940s, with higher maximum altitudes for all except An. pseudopunctipennis (1541 m, 1930 m, 1906 m, 1233 m and 1873 m, respectively). During larval collections, to characterize species-specific larval habitat, a variety of abiotic and biotic habitat parameters were measured and compared between species-present and species-absent sites using chi-square tests and stepwise binary logistic regression analyses (Chapter 4). An. albimanus was significantly associated with permanent pools with sand substrates and An. pseudopunctipennis with gravel and boulder substrates. Both species were significantly associated with floating cyanobacterial mats and warmer temperatures, which may limit their presence in cooler highland regions. Anopheles punctimacula was collected more often than expected from algae-free, shaded pools with higher-than-average calculated dissolved oxygen. Anopheles oswaldoi s.l., the species occurring on the Amazonian side of the Andes, was associated with permanent, anthropogenic habitats such as roadside ditches and ponds. To address the hypothesis that human land use change is responsible for the emergence of multiple highland Anopheles species by creating larval habitat, common land uses in the western Andes were surveyed for standing water and potential larval habitat suitability (Chapter 5). Rivers and road edges provided large amounts of potentially suitable anopheline habitat in the western Andes, while cattle pasture also created potentially suitable habitat in irrigation canals and watering ponds. Other common land uses surveyed (banana farms, sugarcane plantations, mixed tree plantations, and empty lots) were usually established on steep slopes and had very little standing water present. Using distribution and larval habitat data, a GIS-based larval habitat distribution model for the common western species was constructed in ArcGIS v.l 0 (ESRI 2010) using derived data layers from field measurements and other sources (Chapter 6). The additive model predicted 76.4 - 97.9% of the field-observed collection localities of An. albimanus, An. pseudopunctipennis and An. punctimacula, although it could not accurately distinguish between species-absent and speciespresent sites due to its coarse scale. The model predicted distributional expansion and/or shift of one or more anopheline species into the following highland valleys with climate warming: Mira/Chota, Imbabura province, Tumbaco, Pichincha province, Pallatanga and Sibambe, Chimborazo province, and Yungilla, Azuay province. These valleys may serve as targeted sites of future monitoring to prevent highland epidemics of malaria. The human perceptions of malaria and mosquitoes in relation to land management practices were assessed through an interview-based survey (n=262) in both highlands and lowlands, of male and female land owners and managers of five property types (Chapter 7). Although respondents had a strong understanding of where the disease occurs in their own country and of the basic relationship among standing water, mosquitoes and malaria, about half of respondents in potential risk areas denied the current possibility of malaria infection on their own property. As well, about half of respondents with potential anopheline larval habitat did not report its presence, likely due to a highly specific definition of suitable mosquito habitat. Most respondents who are considered at risk of malaria currently use at least one type of mosquito bite prevention, most commonly bed nets. In conclusion, this interdisciplinary thesis examines the occurrence of Anopheles species in the lowland transition area and highlands in Ecuador, from a historic, geographic, ecological and sociological perspective.