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Molecular and neural plasticity in the pheromone response of the corn earworm moth (Helicoverpa zea)
No full textSexual communication in the moth Helicoverpa zea (corn earworm) depends on males detecting and orienting to sex pheromone blends released by females. Trichoid sensilla on male antennae contain olfactory sensory neurons (OSNs) with olfactory receptors (ORs) which are tuned to specific chemicals in the blends of conspecific and heterospecific females. Pre-exposure of moths to pheromones can cause long-term alterations in OSN sensitivity and mating behaviors, but mechanisms underlying this plasticity are unknown. Some evidence suggests plasticity could be driven by alterations in expression of ORs detecting pheromones, although this claim is debated. My objective was to determine how pre-exposure to sex pheromone components could alter OR gene expression and/or electroantennogram (EAG) sensitivity in H. zea, and if these effects were dependent on exposure time or concentration of stimulus. Isolated, 2-4-day-old moths were exposed to different concentrations of conspecific or heterospecific pheromone components for 1 or 24 hours. Antennae were removed and used for either quantitative PCR to detect differences in OR gene expression or EAGs to measure the sensitivity of OSNs. Alterations in OR gene expression were found in three trials, but patterns of expression were inconsistent. Pre-exposure to 6 mg of Z11-16:Ald in males for 24 hours increased EAG responses to most pheromone components and linalool, while pre-exposure to 6 mg of Z9-16:Ald for 24 hours decreased EAG responses to Z9-16:Ald and linalool in females. No consistent link between OR gene expression and EAG sensitivity was found. This research will provide insight into mechanisms underlying insect olfaction and potentially improve pheromone-based pest control methods
Automated sinkhole delineation using lidar in the Cumberland Basin, Nova Scotia
No full textThe province of Nova Scotia is partially underlain by Carboniferous evaporites of the Windsor Group (e.g., anhydrate, gypsum, halite); these are weak, ductile rocks that are fundamental to local and regional geology including halokinesis. The Cumberland Basin, one of many sub-basins that define the larger Maritimes Basin, has significant amounts of Windsor Group evaporites near the surface. The tectonic history, including periods of transtension to transpression associated with movement across the Cobequid-Chedabucto fault system, has promoted planes of weakness and mobility within and adjacent to salt layers. In the more recent geologic past, karstic geomorphological features formed from the dissolution and erosion of weak evaporites near the surface that resulted in evident topographic depressions and surface collapse structures commonly known as sinkholes. Sinkhole formation has negatively impacted infrastructure across the Cumberland Basin, including adjacent to the Trans-Canada Highway and on private residences. This study has created an automated sinkhole delineation method to accurately locate sinkholes in the Cumberland Basin using Provincial LiDAR data. A geospatial workflow, utilizing ArcGIS software and 'ModelBuilder', has been produced that can locate and predict sinkhole locations. This new model allows us to better decipher the complex geological history of Windsor Group evaporites in the Cumberland Basin and to further define high-risk geohazard zones across the region. This project will improve the resolution of the current Provincial Karst Risk Map and is a first step towards creating an encompassing sinkhole database across Nova Scotia. Ultimately, this project will result in an increased understanding of evaporite-related geohazards by informing the public and professionals of sinkhole formation risk.</p
Lithology and geochemistry of the Nicola Group volcanic and volcaniclastic Host rocks to the Copper Mountain alkaline copper-gold porphyry Deposit, Princeton, British Columbia, Canada.
No full textThe upper Triassic Nicola Group is a volcanic and volcaniclastic rock succession hosting the Copper Mountain alkalic porphyry Cu-Au deposit south of Princeton, British Columbia, Canada. Mineralization occurs where diorite to monzonite Lost Horse Intrusive Complex stocks and dykes intrude the Nicola Group in a WNW-ESE trending belt bounded by the Copper Mountain Stock on the south, and the Smelter Lake and Voigt Stocks, and Lost Horse Intrusive Complex on the north. During 2021 field work, 305 field stations were mapped and sampled proximal to the Copper Mountain Mine, revealing the presence of fragmental rocks, lava flows, volcaniclastic rocks, tuffs, and cut by abundant intrusive dykes. Ninety-five volcanic and volcaniclastic rock samples were lithogeochemically analyzed and evaluated using molar element ratio (MER) techniques. Forty-eight of these samples were cut into thin sections for petrographic examination. Results illustrate that Nicola Group rocks occur in two packages in the Copper Mountain area: green, altered Wolf Creek Formation rocks, and grey, relatively unaltered Kennedy Lake formation rocks. The latter occur west of the Boundary Fault and exhibits minor alteration, amygdales, and limestone breccia fragments suggesting deposition in a shallow sub-aqueous or sub-aerial setting. The former exhibits seafloor alteration to chlorite, epidote, and calcite and lacks shallow water deposition evidence. Within Wolf Creek volcanic and volcaniclastic rocks, MER analysis reveals that plagioclase and clinopyroxene fractionation or sorting, and quartz and plagioclase sorting took place, and that significant alteration of plagioclase to chlorite and plagioclase to chlorite+quartz occurred, respectively. These alteration reactions likely took place during low-grade, sub-isochemical seafloor metasomatism in a subaqueous setting. Kennedy Lake formation rocks do not exhibit similar seafloor alteration or this plagioclase to chlorite reaction.</p
The psychological and psychosocial benefits of savouring moments with your furry loved one
No full textThe current study aimed to investigate the impact of savouring on psychological well-being and loneliness in companion animal owners. Participants (N = 98) completed an online survey to assess tendency to savour, animal attachment, psychological well-being, and loneliness. It was hypothesized that the tendency to savour moments with one's companion animal and animal attachment would be positively correlated with psychological well-being, negatively correlated with loneliness, and would also significantly predict levels of psychological well-being and loneliness. Correlation analyses were conducted to assess these relationships. Although no significant relationships were found between tendency to savour, animal attachment, psychological well-being, and loneliness, some initial findings hint at the importance of savouring moments with animals. This study is a first attempt in assessing the possible benefits of savouring time with companion animals
A preliminary examination of quantitative training and tools in Atlantic Canadian universities
No full textThe quantitative training and tools environment is rapidly changing from what it was 20 years ago. Modern tools and new approaches in how statistical analysis is taught and increased access to more sophisticated analyses in research through improved tools are fast-growing, and there is concern that university curricula are not keeping pace. In the fall of 2021, a survey was released to the Maple League and other Atlantic Canadian universities to try and capture the pulse of quantitative training (primarily through statistics courses) and quantitative tools used within statistical training and other courses. Only a small fraction of students reported learning well and gaps were identified in the teaching of collaborative work such as data management and peer training. While these results were only a preliminary analysis of a broader survey, some
conclusions were apparent including having increased group work or larger projects coupled with more attention to quantitative tool training as possible solutions to bridge some gaps. Further investigation is also required to fully understand whether issues in statistics courses are simply due to a lack of individual understanding, or students not having the tools to understand statistics as an investigative process
Effects of microplastics on vector-related physiology and infection success of Hepatozoon clamate in its mosquito host, Culex territans
No full textMosquito larvae ingest microplastics in their aquatic habitat and can retain them within their Malpighian tubules through metamorphosis into adulthood, where many go on to become vectors of disease that pose a threat to humans and wildlife. Retention of microplastics within the Malpighian tubules is significant, as this is the same developmental location of the anuran blood parasite, Hepatozoon clamatae, within its
mosquito vector, Culex territans. The objectives of this study were to determine if microplastic contamination modifies the infection success of H. clamatae in C. territans and to investigate if this contamination alters aspects of mosquito physiology that contribute to vector success. Measures of physiology that are related to vector success, such as developmental rate, post-eclosion survival, and body size were investigated in C.
territans that were raised in low (20 microplastic beads /mL), high (200 microplastic beads /mL), and control (0 microplastic beads /mL) microplastic treatments. Additionally, to measure parasite success, parasite load in infected mosquitos was quantified using qPCR and compared between treatment groups. Exposure to microplastics did not cause significant differences in the measures of vector physiology examined in this study; however, exposure may have the potential to decrease post-eclosion survival. Further, microplastic contamination did not significantly alter parasite load; however, mosquitoes in the control treatment showed higher amounts of parasite DNA compared to the treatment groups, indicating a higher level of infection, and a wider variety in parasite load. These findings suggest that exposure to microplastics has the potential to effect mosquito physiology, resulting in decreased parasite success and reduced vector competence. Future work should help illuminate these effects further
Impact, feasibility, and assessment of virtual physical activity programming for individuals with disabilities
No full textDespite its known benefits, physical activity levels have consistently been lower than recommended among Canadian youth and adults, with levels even lower for those individuals with disabilities. These levels further plummeted through the COVID-19 pandemic due to in-person program restrictions. To combat the lack of program opportunities, the Acadia S.M.I.L.E. program reinvented the typical session into a virtual format. The purpose of this study was to observe and assess the effectiveness, impact, and feasibility of virtual physical activity programming for individuals with disabilities. The program was implemented for eight weeks
between September and December of 2020. Three weeks throughout the term, a live virtual programming session occurred in addition to the weekly At-Home Activity Guides that were sent. A mixed-methodological case study approach was used to observe the effects of the program on functioning, physical literacy, physical activity of the participant, and support, regulation, and physical activity behaviours of the caregiver. Paired samples t-test analysis (p ≤ 0.05) of pre and post programming surveys showed no significant difference in physical literacy, physical activity, or caregiver support behaviours and weekly surveys showed low participation (μ=42.3%) with the At-Home Activity guides. Thematic analysis of caregiver and leader interviews presented five prominent themes: (a) program impact on physical activity, (b) virtual impact on programming, (c) program impact on social, cognitive, and motor goals, (d) impact of program design, and (e) program feasibility for families. Analysis of quantitative and qualitative data presented flaws within program creation yet showed the program to be beneficial for the physical literacy and physical activity of the participants. Future application of this program is to increase accessibility of the S.M.I.L.E. program and additional research should be conducted to further understand the effects of virtual physical literacy and physical activity programming
Investigating the use of face video data to measure mental health
No full textDue to the increase in mental distress and suicidality caused by COVID-19, as well as the growing humanitarian crises around the world, the need for mental health screening and treatment is increasing. A proactive mental health screening tool that uses face video data could help identify when individuals need help. The current exploratory study investigates the ability to associate facial behavior, specifically Eye-Blink Rate (EBR) and facial affect, with measures of depression (CESD-R), attachment style (ECR-RS), mood (POMS), and empathy (EQ). To collect facial behavior data remotely, the iMotions Home Access System was used. Facial behavior was measured using the AFFDEX automated facial affect coding algorithm and passed through an R script to determine metrics of interest. The study used a within-subject design (N = 49). Each participant completed a positive condition, which was primed with a positive YouTube Video, and negative condition, which was primed with a news clip about COVID-19. For each condition, participants completed tasks including a Passive viewing task, Narrative task, and three Motor tasks (COMMAND, IMITATE, and OPPOSITE). Key findings found individuals exhibit more positive facial expression during positive conditions (p < .001) and exhibit more facial expressions during Narrative tasks versus Passive viewing (p < .001). Findings also found differences in response time when imitating expressions compared to making OPPOSITE expressions (p < .001). Additionally, findings found EBR to be significantly affected by task (p < .001)
In times of movement, the voices fall silent investigating the role of migration policy in Cuban regime stability under Fidel Castro
No full textIn order to examine the greater issue of Cuban regime stability and resilience, my research focuses on the question of how shifts in Cuban migration policy during Fidel Castro's time in office impacted the government's overall stability. Throughout the duration of the Fidel Castro government, the Cuban state experienced several political and economic crises which threatened the overall stability of the regime. Despite this, the regime was able to remain relatively stable up to and beyond Castro's retirement in 2006. I argue that immigration was a major reason for this stability. When faced with significant political and economic crises, the Castro government repeatedly allowed for its citizens to migrate off of the island, thereby dispelling dangerous anti-government sentiment, opening new economic opportunities for the regime, and creating the conditions needed to force United States co-operation on migration formalization. To demonstrate this dynamic, I utilize a Historical Process Tracing methodology to examine the four largest periods of migration in the nation's history under Castro. Drawing on data from available secondary sources, I argue that these four cases were each proceeded by periods of significant political or economic crisis. Additionally, I show that as a direct result of migration, the potential destabilizing forces of these crises were mitigated or eliminated altogether
Successive generalized confidence intervals
No full textThe majority of work on multiple comparisons is on comparing the means of k ⩾3 populations following the work of Tukey (1953) on pairwise comparisons of k population means, of Dunnett (1955) on comparisons of several means with a control mean, and of Scheff ́e (1953) on all-contrast comparisons among the population means. This thesis focuses on five different methods to construct simultaneous confidence intervals for
successive comparisons under heteroscedasticity. Th five methods are the MaxT method and MinP method introduced by Westfall and Young (1993) along with the F1 and F2 methods introduced by Xiong and Mu (2009) and the H method introduced in Hannig et al. (2006). Two types of fiducial generalized pivotal quantities (FGPQ) based confidence intervals by Xiong and Mu (2009) and one FGPQ based confidence interval by Hannig et al. (2006). These five methods were developed for two-sided pairwise comparisons. Weprove that the FGPQ-based successive confidence intervals have asymptotically correct coverage. Simulation studies and numerical examples are presented