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    The use of interactive whiteboards by Prince Edward Island high school teachers

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    This Masters of Education thesis used a questionnaire to examine Prince Edward Island high school teachers’ self-reported practices related to interactive whiteboards in their classrooms and the factors influencing their interactive whiteboard use. Despite research suggesting that interactive whiteboards have the potential to improve student academic achievement, the extent to which this technology can actually achieve these claims was likely dependent on many factors. Factors identified in this thesis as hindering teachers’ interactive whiteboard use and by extension, students’ learning, were the understanding of what interactivity with an interactive whiteboard is, teachers’ attitudes towards using interactive whiteboards, and the theoretical and practical training provided to teachers

    Light and ultramicroscopical aspects of the in vitro development of Hematodinium sp. (Dinoflagellata) from Atlantic snow crabs (Chionoecetes opilio)

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    Hematodinium is a parasitic dinoflagellate of numerous crustacean species, including the economically important Atlantic snow crab, Chionoecetes opilio. The parasite was isolated from C. opilio in the fall of 2010 and 2011 and cultured in vitro. Several media were tested, with Nephrops medium yielding superior results. Life stages were characterized using light, scanning and transmission electron microscopy. This is the first time Hematodinium has been isolated from C. opilio and cultured in vitro, and is only the second in vitro study on Hematodinium which used electron microscopy. Numerous life stages were observed: amoeboid trophonts, sporonts, sheet-like and arachnoid coenocytes, dinospores, post-dinospores, and schizonts. In crab hemolymph, amoeboid trophonts and sporonts were observed. In cultures that were seeded with sporonts, further progression to motile dinospore stages occurred; however, those seeded with amoeboid trophonts did not progress to dinospores, often remaining as amoeboid trophonts or occasionally forming schizonts. Additionally, two types of coenocytes were associated with sporonts: sheet-like and arachnoid coenocytes. Only sheet-like coenocytes were associated with trophonts. Trophonts that were morphologically different were ultrastructurally similar, thus no distinction between filamentous and amoeboid trophonts was made. Ultrastructurally, trophonts possessed amphiesmal vesicle membranes, nuclei with permanently condensed chromosomes, mitochondria with tubular cristae, lipid droplets, and lipofuscin granules. Lipofuscin granules were characterized by their autofluorescence and ultrastructural similarity to lipofuscin granules found in other invertebrates and vertebrates. Additionally, lipofuscin granules appeared to degranulate or to be expelled from the cell during in vitro cultivation. The exact mechanism of this is unknown. Sporonts possessed all the features noted for trophonts and also had trichocysts. Mature trichocysts were long, rectangular shaped organelles with a width of 223 ± 2.11 nm (n=100) and of unknown length. Trichocyst development was examined ultrastructurally. Developing trichocysts were associated with the Golgi apparatus and first appeared as large vesicles containing a homogeneous, granular material. During development, the granular material condensed to form a crystalline core. Mature trichocysts were characterized by an electron dense crystalline core surrounded with a tightly juxtaposed single membrane. Early sporonts appeared similar to amoeboid trophonts in morphology; but became more spherical prior to dinospore formation. Late sporonts divided into four daughter cells, indicating a significant replicative step. Dinospores shared all ultrastructural features of sporonts, but possessed two flagella: one transverse and one longitudinal for motility. All dinospores were morphologically identical and resembled the macrodinospores observed in other Hematodinium spp. No microdinospores were observed; this lack of detection is likely due to the low number of observed cultures that progressed to the dinospore stage. After ~ 2 weeks in vitro, dinospores lost their flagella, and became more spherical. Furthermore, the nuclear structure was dissimilar to other stages, with beaded chromatin only evident along the periphery of the nucleus in addition to a single bead in the centre, rather than ubiquitous throughout the nucleus. Thus these were termed ‘post-dinospores’. Additionally, schizonts were noted as very large cells with large, relatively empty lipofuscin granules. Schizonts were only seen in contaminated or old cultures, and were thus considered as an abnormal form. Notably, no viable gorgonlocks or clump colonies were observed as noted in Hematodinium sp. from other crustacean hosts. In the present study, unique filopodia-like structures were observed protruding from early sporonts and trophonts and attached to neighbouring cells. Cryopreservation of Hematodinium was also attempted on sporonts and trophonts. Although recovery rates were very low, viable Hematodinium survived ~ 3 months in cryostorage. Two cryoprotectants, 3% glycerol and 10% DMSO, yielded positive results. This is the first successful cryopreservation of Hematodinium

    An in vitro comparison of the osteogenic potential of equine stem cell populations and subpopulations from multiple tissue sources

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    An in vitro comparison of the osteogenic potential of equine stem cell populations and subpopulations from multiple tissue sources was made to identify the ideal equine donor tissue as a source of MSCs to promote bone healing. Equine muscle tissue– and periosteal tissue–derived cells where characterized as mesenchymal stem cells (MSCs) and their proliferation capacity and osteogenic potential was assessed in comparison with bone marrow– and adipose tissue–derived MSCs. Cells were isolated from skeletal muscle, periosteal, and adipose tissues, and sternal bone marrow aspirates. Morphology, adherence to plastic, trilineage differentiation, and detection of stem cell surface markers CD44 and CD90 were used to characterize cells as MSCs. Osteogenic potential of MSCs was measured by osteocalcin gene expression. Mesenchymal stromal cell cultures were counted at 24, 48, 72, and 96 hours to determine tissue-specific MSC proliferative capacity. Muscle MSCs (MMSCs), periosteum MSCs (PMSCs), and adipose MSCs (AMSCs) proliferated significantly faster than did bone marrow MSCs (BMSCs) at 72 and 96 hours. Non-equilibrium gravitational field-flow fractionation (GrFFF) was validated as a method for sorting MSCs from four donor sources (muscle, periosteum, bone marrow, and adipose tissue) into subpopulations. Aliquots of MSCs from each tissue source were consistently separated into 6 fractions by continuous flow (GrFFF proprietary system) and these fractions remained viable for use in further assays. Absorbencies (OD) were compared, and trilineage assays performed. Statistical analysis of the fraction absorbencies (OD) revealed a P-value of <0.05 when fraction 2 and 3 were compared to fractions 1, 4, 5, and 6. GrFFF was used to sort MMSCs and BMSCs into subpopulations and perform assays allowing comparison of their osteogenic capabilities. Aliquots of MMSCs and BMSCs were sorted into 5 fractions using non-equilibrium GrFFF. Pooled fractions were cultured and expanded for assays including: flow cytometry, histochemistry, bone nodule assays, and real time PCR to identify upregulation of osteocalcin, RUNX2, and osterix. There was significant upregulation of osteocalcin, RUNX2, and osterix for the BMSC fraction 4 with P<0.00001 indicating high osteogenic potential. Flow cytometry revealed different cell size and granularity for BMSC fraction 4 and MMSC fraction 2 when compared with unsorted controls and other fractions. Histochemistry and bone nodule assays revealed positive staining nodules but no significant differences between tissues or fractions. It was concluded that 1) equine muscle and periosteum are sources of MSCs that have osteogenic potential comparable to that of equine adipose- and bone marrow–derived MSCs, 2) non-equilibrium GrFFF is a valid method for sorting equine MMSCs, PMSCs, BMSCs, AMSCs into subpopulations that remain viable and 3) subpopulations of MSCs exist and have different osteogenic capacities within equine muscle and bone marrow derived sources. These findings are important contributions to equine stem cell therapy and bone healing in veterinary medicine

    The lived experiences of female leaders in two university settings: Perceived supports, barriers, and challenges

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    The dearth of women in higher education both as full professors and senior administrators is alarming, and the factors impeding their entrance and limiting their advancement are relatively unknown. The purpose of this research was to document the lived experiences of women leaders who were full professors or who held senior leadership positions in two universities in Atlantic Canada. I researched the perceived supports, challenges, and barriers that women leaders faced in their professional lives, as well as the influence of gender in their leadership positions. I approached the research from a social constructivism standpoint and utilized a phenomenological research design. I used standpoint theory to analyze the data. Data sources included two interviews with each participant and a seven-day leadership journal from each participant. Women noted multiple supports, challenges, and barriers in their personal and professional lives. Supports include husbands, mentors, workshops, and networking. Challenges and barriers included children, colleagues, work/life conflicts, invisibility, and a lack of leadership development programs. Findings indicated that gender equality has not been achieved in the postsecondary setting, and gendered expectations, sexism, and discrimination remain strong barriers for women. Applying standpoint theory, the social location of the participants impacted their lives, opinions, and views of leadership in postsecondary institutions. Their lived realities and experiences changed over time as the academic and institutional culture changed over time, and, as such, their views about women and leadership were altered. Implications of this work are that university leaders need to create supports for women and make them easily accessible, and create a women-friendly environment that will increase the ease with which women can enter, advance, and succeed in the institution. Keywords: women‘s studies, leadership, higher education, senior administration, professorshi

    Immunotoxic effects of benzo[a]pyrene on rainbow trout (Oncorhynchus mykiss)

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    Polycyclic aromatic hydrocarbons (PAHs) are a group of compounds with immunotoxic and carcinogenic potential that may pose a threat to fish populations. The mechanism underlying immune toxicity of PAHs in fishes remains unclear. Some evidence supports the requirement for metabolism to more toxic metabolites. This twopart study aims to utilize a newly developed fish immunotoxicology model to determine the immune tissue/cell population level effects of PAHs on rainbow trout, using benzo[a]pyrene (BaP) as a representative immunotoxic PAH. In the first part of the study, intraperitoneal injection of 25 or 100 mg/kg BaP resulted in sustained exposure as indicated by biliary fluorescence at BaP wavelengths for up to 42 d. A new flow cytometry method for absolute counts of differential leukocyte distributions in spleen, blood, and head kidney was developed by combining absolute quantitative counts of total leukocytes in the tissue (3,3′-dihexyloxacarbocyanine iodide (DiOC6) dye) with relative differential counts using monoclonal antibodies for B cells, T cells, myeloid cells, and thrombocytes. Experiments indicated dose- and time-dependent decreases in the absolute number of B cells, myeloid cells, or T cells in blood, spleen, or head kidney after 7, 14 or 21 d of exposure. There was no change in the absolute numbers of erythrocytes or thrombocytes in any tissue. When rainbow trout were exposed to inactivated Aeromonas salmonicida after a 21 d exposure to 100 mg/kg BaP, circulating antibody concentrations were decreased by 56%. It was concluded that BaP has a cell lineage-specific toxic effect on some immune cells of rainbow trout, and causes a decrease in circulating antibody levels. The second part of the study examined whether intraperitoneal exposure of rainbow trout to BaP caused leukocyte mRNA expression changes in five cytochrome P450 (CYP) enzymes; to their transcription factor, AhR; or to an extrinsic pathway apoptosis checkpoint, p53. mRNA expression was analyzed in immunomagnetically isolated B cells and thrombocytes from blood, spleen, or head kidney in an effort to clarify the tissue and cell specific toxicity of BaP. Significant inductions above control levels were observed in CYP1A1 in liver, blood B cells, and blood thrombocytes; CYP1B1 in blood B cells, and blood thrombocytes; CYP1A3 in liver, blood and spleen B cells; and AhR in spleen thrombocytes. No significant changes were found in CYP1C1, CYP1C2, or p53. Increased mRNA expression was observed 14 d after exposure, indicating a prolonged physiological effect of a single BaP injection. Although there were differences in expression, it was concluded that variations in the presence or induction of CYP enzymes is not enough to explain the difference in toxicity observed between B cells and thrombocytes. An induction of AhR in thrombocytes is interesting, but difficult to explain given current knowledge on endogenous AhR regulation and the limited toxicity in thrombocytes. Overall, our findings provide support for a complex mechanism of toxicity for chronic PAH exposure, and suggest that CYP expression profiles do not fully explain these effects

    Scholarship in abundance: Influence, engagement, and attention in scholarly networks

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    In an era of knowledge abundance, scholars have the capacity to distribute and share ideas and artifacts via digital networks, yet networked scholarly engagement often remains unrecognized within institutional spheres of influence. The purpose of this dissertation study is to explore the meanings constructed and enacted within the networked practices of 13 scholars actively engaged in both institutional and networked participatory scholarship. Using ethnographic methods including participant observation, interviews, and document analysis, the study investigates networks as sites of scholarship, with the intent of furthering institutional academia’s understanding of networked practices. The three papers that make up the dissertation each articulate a specific thread of intersection between institutional and networked scholarship: the first focuses on what counts as academic influence within networked circles, the second on networks’ terms of value and reward, and the third on the relationships between attention, care, and vulnerability in scholarly networks. Together, the papers conclude that networked scholarly practices of engagement align broadly with those of academia, yet enable and demand scholars’ individual cultivation of influence, visibility, and audiences. Thus networked scholarship rewards connection, collaboration, and curation between individuals rather than roles or institutions, fostering cross-disciplinary and public engagement and a bridging of the personal/professional divide. The study contributes to knowledge by situating networked scholarly practices within the scholarly tradition, while articulating the terms on which knowledge abundance and networked practices open up new spheres of opportunity and vulnerability for scholars

    Use of Fourier-transform infrared spectroscopy to determine immunoglobulin status in camelid and equine species

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    Measurement of systemic immunoglobulin (Ig) concentrations in horses and camelids is important for early and accurate diagnosis of immunodeficiencies in order to provide proper medical intervention. As a consequence, there is a demand for up-to-date, economic, rapid and precise diagnostic assays for Igs. Accordingly, multiple methods for the evaluation of Ig concentrations have been evaluated in equine and camelid species, each with particular advantages and disadvantages. Fourier-transform infrared (FTIR) spectroscopy has recently emerged as a powerful diagnostic tool for the quantitative characterization of biological fluids in human and veterinary medicine. In particular, FTIR spectroscopy has proven to be an accurate, economical and reagent-free method for immunoglobulin G (IgG) quantitation in horses. Further research to investigate its potential application in the quantitation of other equine Ig isotypes and IgG subclasses is warranted. Additionally, as rapid quantitative assays for the measurement of camelid serum IgG are limited, further work to assess the use of FTIR spectroscopy in this area is desirable. The objectives of this thesis were: (1) to develop an FTIR-based assay for the measurement of IgG concentrations in alpaca serum and to compare its performance to that of the radial immunodiffusion (RID) assay, and (2) to develop FTIR-based assays for the measurement IgGa, IgGb, IgG(T), IgA, and IgM for equine plasma using ELISA assays as reference tests. The first objective of this thesis was achieved by performing RID IgG assays and collecting FTIR spectra for 175 alpaca serum samples. A FTIR-based assay was built using partial least squares regression to convert the spectroscopic data into quantitative IgG values which were compared to the RID results. Correlation coefficients and scatter plots indicated good to excellent levels of agreement between the assays. The results suggest that FTIR spectroscopy may be a useful method for IgG measurement in alpaca serum. For the second objective, IgGa, IgGb, IgG(T), IgA, and IgM concentrations were determined by ELISA assays and FTIR spectra were collected for 100 equine plasma samples. The spectra were randomly divided into training and prediction sets. The training set was used to build a calibration model for each Ig isotype or IgG subclass using partial least squares regression, while the prediction set was used to test the performance of the developed models. Pearson correlation coefficients and scatter plots displayed moderate to good agreement between FTIR and ELISA IgGb assay results but poor overall agreement for IgGa, IgG(T), IgA and IgM assay results. As well, significant differences were noted between the ELISA results of this study and the reviewed studies from the published literature. At present, a FTIR spectroscopic approach is an inaccurate technique for the measurement of Ig isotypes or IgG subclasses in equine plasma

    Emerging technologies for the assessment of bovine immunoglobulins in biofluids

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    Measurement of bovine serum and colostrum immunoglobulin G (IgG) concentration is critical for colostrum and calf health monitoring in order to determine the colostrum quality and failure of transfer of passive immunity (FTPI), which is considered the main reason for increased morbidity and mortality rates in newborn calves. Several qualitative and quantitative assays are available, but radial immunodiffusion assay is acknowledged as the reference method. However, it is expensive and takes a long time to obtain the results, which prevents the identification of calves with FTPI prior to gut closure. As a consequence, there is a demand for rapid, accurate and inexpensive diagnostic assays for IgG. The objectives of this thesis were: (1) to develop and validate an infrared (IR) spectroscopy based assay for quantification of bovine serum and colostrum IgG concentration, and (2) to validate a novel and rapid on-farm tool for detection of FTPI in dairy calves and for assessing colostrum quality of dairy cows. Infrared spectroscopy has recently emerged as a powerful, reagent-free diagnostic tool for the quantitative characterization of biological fluids in human and veterinary medicine. We set out to develop a quantitative assay based on IR spectroscopy to measure bovine serum and colostrum IgG concentration and to compare the values with that of the RID assay. Although there are a number of IR spectroscopic sampling techniques, in this research, transmission-IR and attenuated total reflectance (ATR-IR) spectroscopy were used. For quantification of bovine serum IgG concentration, transmission-IR and ATR-IR assays were developed using 250 serum samples collected from calves. The IgG concentration measured by both assays showed excellent correlation with RID-measured IgG. Also, both IR-based assays showed potential for detection of FTPI with good to excellent sensitivity, specificity and accuracy. The transmission-IR assay showed slightly higher precision than the ATR-IR assay. However, the ATR-IR assay is more appropriate for farm and veterinary clinic use. For quantification of colostral IgG concentration, a transmission-IR assay was developed using 251 colostrum samples. The IgG measured by the IR assay showed excellent levels of agreement with the RID assay. The results suggest that IR spectroscopy may be a useful method for colostrum monitoring programs. Evaluation of an initial version of ZAPvet Bovine IgG test for detection of calves with and without FTPI revealed that the ZAPvet test is relatively sensitive and would be acceptable as an initial screening test for diagnosis of FTPI in dairy calves. However, the low specificity of ZAPvet test would result in over prediction of FTPI incidence, which could result in unnecessary interventions for calves with adequate transfer of passive immunity. Validation of refractometers, either digital Brix (Atago Co. Ltd; WA) or optical STP (Westover RHC-200ATC handheld refractometer, Woodinville, WA), for detection of FTPI in 202 dairy calves, and digital Brix (Atago Co. Ltd; WA) or optical Brix (model 300001; SPER Scientific, Scottsdale, AZ), for assessing of quality of 251 colostrum samples, revealed that the digital and optical refractometers have good potential for being a useful and practical on-farm management tools to be included in colostrum and calf health monitoring program on dairy operations. Furthermore, the two refractometers performed similarly for detection of FTPI in dairy calves and for assessing of colostrum quality of dairy cows with cut-points slightly higher than that reported in recent studies

    Assessment of balance behaviour, eye-movement, and attention: A step towards a more comprehensive concussion return-to-play protocol

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    Concerns associated with head injuries have come to the forefront as head trauma events in the National Hockey League (NHL) and National Football League (NFL) bring to light the prevalence and effects of concussions. Accordingly, proper assessment and management of head injuries are growing areas of interest among the general public and researchers. At this point, most sports leagues and teams have established the need for concussion protocols and have set standards that must be met when an injury occurs or is suspected. In an effort to make assessments accessible to the general public, many tests are simplified to computer tests that require very little training or cost to administer. However, these assessment protocols are often not thorough enough to detect the various potential deficits and symptoms that can occur after a head injury. Of the various possible symptoms of a concussion, the highest testable deficits are balance dysfunction and dizziness. Further, most tests used to evaluate athletes comprehensively, are not ecologically relevant. The increased challenges athletes incur through their participation in sport in their everyday lives must be considered when developing baseline testing. The present research study aimed to aid in the correction of the previously mentioned inadequacies. A test-retest design used 4 instruments to evaluate 20 healthy individuals ranging in age from 17-25. The BESS, ANT, Wii Fit Balance Board, and Mobile Eye XG glasses were used to measure static and dynamic balance, attention, and gaze. The results indicate that the selected measures were stable and consistent with traditionally used protocols for healthy individuals. By analyzing the test-retest reliability of the Soccer Heading Game on the Wii Fit Balance Board while wearing an eye-tracking device, a more ecologically relevant and comprehensive test is available to assess an athlete's balance

    Discovery of novel molecular immune mediators in the American lobster (Homarus americanus) during bacterial, eukaryotic parasitic and viral challenges

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    The American lobster (Homarus americanus) is the most economically significant commercial fishery species in Canada. The Canadian lobster fishery provides tens of thousands of jobs, and is the economic driver of hundreds of rural communities in Atlantic Canada and Quebec. The adult lobster is susceptible to relatively few pathogens but very little is known about how its immune system is capable of mediating this pathogen resistance. Additionally, there is no definitive clinical biomarker that is capable of assessing overall lobster health, something that would be valuable to a fishery where lobsters are the most lucrative when they are sold as a live product. The purpose of this project was to discover how the H. americanus humoral immune system responds to bacterial, eukaryotic parasitic and viral pathogens. This was performed by using high-throughput transcriptomics, in the form of microarray gene-expression analysis, to monitor the expression of classical immune molecules, as well as discover novel immune mediators. This project discovered hundreds of new H. americanus genes that have not previously been associated with either lobster or crustacean immunity. The expression of these novel immune-related genes is especially interesting because over half of them have no similarity to proteins in GenBank, little if any functional characterization, and pathogen class-specific expression. The conventional immune paradigm for any crustacean innate immune response is that it is non-specific and responds similarly to all microorganisms, pathogenic or not. These studies have determined that this is not the case. There is consistent and unique differential expression of genes for each of the pathogen classes examined, and even differential expression of isoforms within gene families that is pathogen dependent. Among the most interesting genes that have been discovered are the six isoforms of anti-lipopolysaccharide factor family (ALFHa-1, ALFHa-2, ALFHa-3, ALFHa-4, ALFHa-6 and ALFHa-7), acute phase serum amyloid protein A (SAA) and trypsin 1b. Four ALFHa family isoforms are differentially expressed during bacterial, Aerococcus viridans var. homari, and parasitic, Anophryoides haemophila, infections, where the differential expression of ALFHa-4 and ALFHa-2 isoforms are the most significant during bacterial and parasitic infections respectively. However, none of the six ALFHa genes are differentially expressed during viral, White Spot Syndrome Virus, infection. SAA is important because its expression is significantly increased in moribund lobsters during bacterial and parasitic infections, although not in viral infections. The protein sequence of SAA is highly conserved between humans and H. americanus suggesting the conservation of an important biological function such as innate immune activation. Trypsin 1b is the only gene that was differentially expressed during all three pathogen challenges. It is unclear what immunological role this gene plays in lobster or crustacean immunity but it is likely pivotal to immune activation, and a promising lobster health biomarker. These findings have made significant advances to our understanding of lobster immunity which can be applied to crustacean immunology as a whole. The lobster immune response can no longer be thought of a generalized non-specific response, but as one tailored to the invading pathogen


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