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Phloridzin docosahexaenoate ester, a novel acylated phytochemical originating from apples and fish oil, inhibits colon cancer cell growth in vitro
No full textPhytochemicals, a diverse group of naturally occurring compounds found within plants, have shown beneficial properties for human health, specifically anticancer properties. Phloridzin (PZ), a flavonoid based phytochemical commonly found in the seed, peel, and bark of apples, has specifically been found to display antioxidant properties and the ability to reduce cancer growth in vitro. Other food-derived biomolecules, such as docosahexaenoic acid (DHA) commonly found in fish oils, have also been shown to prevent the replication of cancer cells while not having harmful effects on non-cancerous cells in vitro and in vivo. PZ and DHA were synthesized together through an acetyl reaction to produce PZ-DHA increasing the products bioavailability, cellular uptake, and lipophilicity. PZ-DHA has been found to be selectively cytotoxic to various cancer types. In HCT-116 colon cancer cells, preliminary data have demonstrated that PZ-DHA significantly decreases in vitro-spheroid growth in a three-dimensional model in a dose-dependent manner. Flow cytometric analysis suggests that PZ-DHA may regulate the cell cycle of HCT-116 cells. PZ-DHA has displayed regulatory effects on proteins associated with the PI3K/AKT pathway and decreases the expression of extra cellular matrix (ECM) degradation protein matrix metallopeptidase (MMP)2. With colon cancer presenting as the third most common cancer in Canada, there is the need for less toxic and limiting treatments for the disease. PZ-DHA is being presented as a potential novel treatment alternative, with the need for further investigation.</p
It's pointless anyway: understanding dire messaging, fatalism, and low intentions to address the climate crisis
No full textClimate change messaging can be inherently threatening, which may precipitate counterproductive responses to the climate problem. The present study sought to apply a terror management perspective to investigate how climate change messaging promotes fatalism towards the climate crisis and subsequently reduces environmental behavioural intentions. Individual differences in investment in an environmental worldview and trait self-esteem were examined as potential moderators of these reactions. Participants were randomly assigned to a climate change or a control messaging condition and then completed self-report measures of fatalism and intentions to engage in pro-environmental behaviour. Although not fully anticipated, results indicated that people high in self-esteem but low in environmental worldview presented an increase in fatalism and a decrease in behavioural intentions following the climate change messaging condition. These results may suggest that people who obtain high self-esteem from sources that are unrelated to the environment become strategically fatalistic towards the climate crisis, and maintain very little intension to engage in pro-environmental behaviours because they are firmly buffered against death-related anxiety. Discussion focuses on implications for understanding individual differences in response to climate change messaging, and the persistent problem of non-action in the face of a growing problem for humanity
Petrological and U-Pb zircon age constraints for metamorphic rocks of the northeastern Cape Breton Highlands, Nova Scotia: new insights into the geological history of the Aspy terrane
No full textGeological mapping, petrological studies and U-Pb (zircon) dating were done to better characterize metasedimentary and metaigneous rock units in the northeastern Aspy terrane, Cape Breton Highlands, Nova Scotia. Foliated biotite monzogranite of the newly recognized South Aspy River pluton has a Silurian age (440.3± 2.1Maor 421.6 ± 4.0 Ma). An early Devonian age for the Glasgow Brook granodiorite pluton was confirmed at 415.7± 2.7Ma, consistent with a previously reported age of 416.0±1.9 Ma. U-Pb (zircon) ages from the Cheticamp Lake Gneiss of 416.9± 1.3 Ma and 415.9± 1.9 Ma, combined with mineralogical and textural similarities, suggests that the Cheticamp Lake orthogneiss and Glasgow Brook pluton may be related. Both the South Aspy River pluton and Glasgow Brook pluton were emplaced in a volcanic-arc tectonic setting and combined with ages of volcanic and plutonic rocks from other parts of the Aspy terrane indicate an extended history of arc magmatism from the early Silurian through the early Devonian. The plutonic units intruded metasedimentary rocks previously assigned to the Money Point Group but now named the Little Southwest Brook formation. The youngest detrital zircon population in a semi-pelitic schist sample provides a maximum depositional age of 441.2 ± 2.5 Ma. Mineral assemblages, lack of evidence for melting, and thermobarometry constrain peak prograde metamorphic conditions to <650 °Cat 5.5 –7kbar. Based on similar lithologies, includingcharac teristic pelitic rocks interlayered with amphibolite and marble as well as similar detrital zircon signatures, the Little Southwest Brook formation is interpreted to be part of the Cape North Group and correlative with high-grade metamorphic rocks elsewhere in the northern, western, and central Aspy terrane. The igneous, metamorphic and deformational history of the area records the Salinic and Acadian orogenies and the Silurian-Devonian collision between the Aspy and Bras d'Or terranes
Anthropogenic subsidies and contaminant biotransport by herring gull (Larus argentatus) in southern Nova Scotia
No full textSeabirds can biotransport contaminants, moving them from marine to terrestrial environments around breeding colonies. This process can have marked impacts on receiving environments and biota. Generalist predators such as herring gulls (Larus argentatus) can exploit a wide range of natural and anthropogenic food items such as waste from fish processing or mink (Mustela vision) farms. The impact of gulls transporting contaminants from anthropogenically sourced food has not been assessed in southern Nova Scotia. To examine foraging patterns, GPS tags were deployed on herring gulls caught at breeding colonies in southern Nova Scotia in 2014, 2015 2018 and 2019. Gulls from all study colonies used anthropogenic food sources extensively. I measured total mercury (THg), persistent organic pollutants (POPs) and a suite of trace elements (TEs) in surface soils from gull colonies and nearby gull-free reference sites to determine if gulls were depositing contaminants from anthropogenic food sources. Additionally, I collected soil cores at different depths from gull colonies to examine deposition of these contaminants temporally. I found little evidence of gull or atmospheric deposition of contaminants through time in cores. I found a consistent THg biotransport signal, but local conditions and other seabird species also likely impact THg accumulation in soils. I also detected a signal of biotransport with respect to some TEs, including zinc and copper. In contrast I did not find that POPs were accumulating in soils at high concentrations. Overall, results suggest that highly mobile and scavenging gulls are biovectors for some contaminants likely derived from anthropogenic food sources and
that generalist predators increase the environmental footprint of these industries that produce abundant waste
Building and maintaining authentic learning experiences: educators' experiences with Mi'kmaw and treaty education in Nova Scotia's public high school social studies classrooms
No full textAs efforts to decolonize education in Canada continue, Nova Scotia models their work after that of Saskatchewan by implementing Treaty Education initiatives and curricula into public schools that speak to the histories and knowledges of Mi'kmaq peoples. However, minimal research has been conducted on the success of such initiatives in the classroom settings. Drawing on data collected through analysis of two curricular documents and five interviews with educators teaching Citizenship 9 and Mi'kmaw Studies 11, this thesis presents the importance of Treaty and Mi'kmaw Studies education, the ways in which several educators incorporate culturally responsive teaching practices and curricula into the classroom, methods of student engagement, and barriers educators face in terms of professional development and classroom resources. My research concludes that although there are current strides to improve the quality of culturally responsive education in Nova Scotia, some educators believe efforts must continue to create authentic learning experiences
Sub-lethal effects of mercury in Leach's Storm-petrels (Oceanodroma leucorhoa)
No full textMercury occurs in food webs both naturally and from human inputs. Methylmercury is toxic, and bioaccumulates and biomagnifies in food webs. Leach's Storm-petrels (Oceanodroma leucorhoa) are an abundant seabird in the North Atlantic, and their diets and tissues can have high levels of mercury. I tested for sublethal associations among blood mercury, feather mercury,
haemoglobin, and blood glucose in breeding storm-petrels. Results from a sample of 26 birds suggested blood mercury concentrations were not associated with levels of haemoglobin (r= -0.28, p = 0.27) or glucose (r 0.23, p = 0.24). Similarly, feather mercury was not a significant predictor of blood glucose (r = 0.13, p = 0.52) or haemoglobin (r = -0.03, p = 0.88). However, I detected higher mercury in storm-petrel feathers than in blood, consistent with predictions that birds shunt toxic heavy metals to inert feather tissues during moulting, reducing body burdens
The effect of age and sex on lower limb biomechanics, and investigating lower limb biomechanical relationships during a vertical drop jump
No full textThe anterior cruciate ligament (ACL) is a passive stabilizer for the knee joint, and functions to primarily restrict anterior tibial translation on the femur. Injury to the ACL is a devastating injury to endure and has become increasingly more common in youth. ACL injury not only takes an athlete out of sport in the short term, but also greatly increases the risk of accelerated osteoarthritis in the knee.Age and sex have shown to be two important determinants of ACL injury risk, as post-pubescent females are to be 2-8 times more likely to sustain a potential ACL injury compared to their male counterparts. There are hormonal and anatomical differences between age and sex groups to be considered, however biomechanical risk factors which have shown to be modifiable, need to be studied further in order to ultimately work on reducing
injury risk through training interventions. While there have been studies that have identified the biomechanical profiles of age and sex groups, little research has attempted to observe the relationship
between adjacent joints during a drop jump task. Therefore, the purpose of the current study was to identify differences in biomechanical patterns between sexes and age groups. It also serves to identify potential relationships between adjacent lower-limb joints during a drop jump task. Male and female athletes were recruited (male=69, female=71) from Acadia University summer camps, Acadia varsity and club sports teams, local soccer and basketball sporting clubs, as well as through word of mouth. Of the 69 males, 33 were considered pre-pubescent (age = 10.6±1.8yrs, height 148.8 ±15.0 cm, weight 40.8 ± 12.0 kg), and
36 were considered post-pubescent (age=20.6±2.1 yrs, height = 182.3 ± 6.6 cm, weight 83.2 ± 10.6 kg). Of the 71 females participating in the study, 31 were considered pre-pubescent (age=11.2 ± 1.5 yrs, height 151.3 ± 9.2 cm, weight 41.5 ± 9.1 kg), and 40 were considered post-pubescent (age= 20.1 ± 1.5 yrs, height 168.2 ± 6.9 cm, weight 69.4 ± 11.3 kg). A double-leg drop-jump protocol was employed to analyze group
mean joint angles at initial contact (IC), maximum joint angles during stance, as well as joint range of motion (ROM) from IC to max. Peak joint moments for the hip, knee and ankle were also analyzed. Joint
angles were calculated in the sagittal plane, with knee frontal plane joint angles also being calculated, while peak joint moments were also calculated in both the sagittal and the frontal planes. Two-way ANOVAs
(p>0.05) were used to calculate age (pre vs post-pubertal) and sex (male vs female) effects as well as age by sex interaction effects. Bonferroni pairwise comparisons were used when an interaction effect was
identified. It was observed that pre-pubescent individuals displayed significantly greater joint angle ROMs in all measures, while post-pubescent individuals displayed greater peak joint moments compared to pre-pubescent participants for all measures except peak knee abduction moment. It is notable that females displayed a greater peak knee abduction angle during the drop jump task. Males displayed a significantly greater peak hip extension moment, knee extension moment, ankle plantarflexion moment, and ankle supination moment, while females displayed greater hip abduction moments. Linear regression analyses show knee flexion ROM to be a significant predictor of ankle and hip ROM in pre-pubescent females, post-pubescent males, and post-pubescent females. These findings provide insight on the difference in biomechanical patterns between age groups and sexes. Future studies should continue to test the validity of using regression analyses between lower-extremity joint biomechanics during athletic movements
Development of statistical tools to analyze young athletes' biomechanics during movement tasks
No full textEvery year in the United States alone, over 200 000 people tear their anterior cruciate ligament (ACL) which is a primary stabilizer of the knee. Of these injuries, 100 000 need reconstructive surgery, and this costs 2 billion USD and places a significant financial burden on the healthcare system. Non-contact sports such as basketball, soccer and volleyball contribute to 70% of all ACL injuries. Female athletes aged 15 to 25 years are two to eight times more likely to tear their ACL compared to their male counterparts. The purpose of this study was to investigate fitting high-dimensional logistic regression models to identify features of athletes' biomechanical waveform data collected at the John MacIntyre motion Lab of Applied Biomechanics. The waveforms were individually summarized by a regression of measured values vs time, using B-spline basis functions. This summarized and reduced the dimensionality from 2424 columns of waveform data down to 264. Each column of waveform data following the B-spline reduction represented a tenth of its original waveform. The B-spline coefficients were then used as the predictors in the logistic regression model with shrinkage penalty. The shrinkage method used in this thesis was the elastic net, which is a hybrid between ridge regression and lasso regression. The elastic net penalty was used since there were more predictor variables than observations, and there was high pairwise correlation between predictors coming from the same waveform. The process was tested on three different classification problems, with a 2-class problem and two 3-class problems. The analysis used 20% of the data as a test set. Within the remaining 80%, 5-fold cross-validation was used to select the elastic net penalty parameters. A logistic regression with elastic net penalty was used to predict participants' age class (young vs old), puberty class (pre vs during vs post-puberty) and a mix of puberty and gender (pre-puberty male and females vs post-puberty males vs post-puberty females). For classifying young vs old participants the model performed with 89% test set accuracy. For classifying pre vs during vs post-puberty the model performed with approximately 67% accuracy. When classifying pre-puberty males and females vs post-puberty males vs post-puberty females the model achieved an accuracy of 95%. The elastic net logistic regression models were able to correctly identify areas of difference between classes' movement patterns. The model built using the elastic net penalty performed significantly better than models built using the ridge regression or lasso regression penalty. The models created were able to accurately separate classes and identify differences in movement patterns while maintaining high levels of interpretabilit
Behavioural and neural effects of prism adaptation in children
No full textBackground. Spatial neglect is a common neurological condition following right-hemisphere stroke that can occur across the lifespan. Prism adaptation (PA) is a promising experimental treatment for spatial neglect but its use has not yet been studied extensively in children. Furthermore, the neuromechanisms underlying the development of PA effects are unknown which has been a barrier to the clinical implementation of the procedure. Method. A new home-friendly PA protocol (Peg-the-Mole or PTM) was used in the present study that examined the effectiveness of this procedure in healthy children. Forty healthy children (8-13 years old) alternated between using prism (5- or 15-degree rightward deviating goggles) and sham goggles with PTM to allow for repeated adaptation. After-effects were measured with proprioceptive and visual pointing outcome tasks administered before and after PTM. Electroencephalographic data was collected during PTM for examination of a possible neurocognitive mechanism (the P300 wave recorded at electrode Pz) that could underlie the development of after-effects. Results. Significant direct effects and after-effects were observed (p < 0.05). PA effects were larger in the 15-degree condition than in the 5-degree condition. A P300 wave was observed during the use of PTM, with a larger amplitude during prism than sham blocks, but only for the 5-degree condition. Implications. The findings confirmed significant adaptation and after-effects in healthy children using PTM. A P300 wave was observed during PTM suggesting that it could reflect a neuromechanism underlying the development of PA after-effects.Keywords: prism adaptation, after-effects, children, EEG, P300</p
Mu Na Kesinukutiwek: engaging the 'Sick Indian' with perspectives of Mi'kmaq on healing and sickness
No full textThis thesis engages with a narrative on Indigenous peoples, one that is created purposefully to maintain current systems of power between Indigenous people and the colonial state by promoting notions of essential difference, essential sickness, and dysfunction. It is in recognition of these notions that the narrative has been named the "Sick Indian". This narrative is directly implicated in the creation of discriminatory policies,
state coercive force in stealing land and resources, issues of sovereignty, and the creation and perpetuation of a specific power relationship between nations. By using Indigenous research methods associated with oral story in recruitment and knowledge generation, the thesis investigates how this narrative emerges in the truths revealed by co-researchers on their lives and their experiences as Mi'kmaw. Conversations with co-
researchers surrounded power, ideas of health, and this concept of the Sick Indian. These interviews explicitly showed that the idea of the purposeful framing of sickness is understood by my Mi'kmaw co-researchers and reveals how the influence of these structures is experienced