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Effect of catnip (Nepeta cataria L.) essential oil on the blacklegged tick (Ixodes scapularis) chemosensory system
No full textNatural products provide a large reservoir of active ingredients that can be used for pest management. Essential oils are an interesting alternative to synthetic pesticides, because they are environmentally friendly and are safer products that can protect humans and animals against pest vectors such as ticks. Because of global warming, the rise in tick population has resulted in an increased risk for the transmission of vector borne diseases, such as Lyme disease which is vectored by the blacklegged tick (Ixodes scapularis Say), and an increase in demand for effective yet safe repellent products. Repellent activity of catnip (Nepeta cataria L.) essential oils (EOs) and the main chemical components were evaluated against I. scapularis adult female ticks. Seven varieties of catnip EOs were analyzed using
GC-MS to determine their chemical compositions. Nepetalactone isomers (76.6 ± 0.3% and 16.9 ± 0.4% relative overall abundance) were detected in only one EO variety. These compounds were linked to the highly repellent action (100% repellency up to 8 hours post-exposure) exerted by the oil in repellent bioassays. The isolation of the nepetalactone isomers was performed through liquid chromatography, and chemical identity of the isomers was confirmed by GC-MS and NMR. Quantification (using a calibration curve and the internal standard method) of catnip EO main components (i.e., nepetalactone, L-menthone, a-pinene, and b-caryophyllene) was performed through GC-MS. The concentration of the major isomer, (4aS, 7S, 7aS)-nepetalactone, was determined to be 80 ± 10 wt% in the New Directions Aromatics Inc. catnip EO. The exposure of repellents and their impact on the tick chemosensory system was also investigated through electrophysiology. The electrophysiological response of adult tick females to a known attractant and host volatile (i.e., butyric acid), pre- and post-exposure to catnip EO, was recorded. Exposure was performed by fumigation assay, where it was found that pre-exposure to catnip EO significantly reduced tick response to butyric acid. Results of this study will contribute to better understanding the response of tick chemosensory system to different essential oil components and better select effective active ingredients for the development of repellent products
Effects of microplastics on mosquito physiology and susceptibility of hepatozoon clamatae in culex territans
No full textMicroplastic pollution poses a threat to environments around the world. Mosquito larvae readily ingest microplastics encountered in aquatic environments and potentially retain them in the Malpighian tubules of terrestrial adults. The influence of microplastics on mosquitoes remains unclear and requires further research. The objectives of this study were to determine whether microplastic contamination alters aspects of vector physiology that contribute to vector competence, and to investigate if this contamination affects the response of Culex territans to the protozoan blood parasites of the genus Hepatozoon. Wild-caught Culex territans were reared in increasing concentrations of polystyrene microplastics, including control (0 beads/mL), low (20 beads/mL), high (200 beads/mL),
and ultra (2000 beads/mL) conditions. Measurements of vector physiology included mortality of larvae, pupae, and adults, developmental rate of larvae, body size of adults, and post-infection survival in the presence of Hepatozoon parasites. Exposure to different levels of microplastics did not significantly affect aspects of vector physiology; however, the time of year when larvae were collected influenced aspects of vector physiology. To investigate potential interactions of microplastics and parasites, the intensity of H. clamatae in infected mosquitoes under different treatments was quantified using qPCR. Parasite intensity was not significantly influenced by microplastic exposure; however, mosquitoes in the control treatment showed higher levels of parasite DNA compared to those exposed to microplastics. Additionally, parasite intensity may correlate with the size of a blood meal ingested by the female mosquito. These findings suggest that microplastic exposure does not affect aspects of vector physiology, but may influence parasite success within the host
Do implicit theories of sexuality shape relationship well-being differently for LGBTQ+ versus NON-LGBTQ+ individuals?
No full textImplicit theories of sexuality are individuals' beliefs as to how sexual satisfaction can be maintained (Maxwell et al., 2017). There are sexual growth beliefs, where effort and work is how sexual satisfaction is maintained, and sexual destiny beliefs, where being with the right partner is how sexual satisfaction is maintained (Maxwell et al., 2017). However, research on implicit theories of sexuality have yet to investigate how these beliefs differ or are similar with LGBTQ+ people. The goal of the current project was to expand the scientific understanding of relationships by asking how LGBTQ+ people and implicit theories of sexuality work together. There were two research questions: (1) do LGBTQ+ people differ on sexual growth and/or sexual destiny beliefs when compared to non-LGBTQ+ people, which we hypothesised that LGBTQ+ would hold higher sexual growth beliefs than non-LGBTQ+ people based on sexual script theory, and (2) does Maxwell et al.'s (2017) findings wherein sexual incompatibility and
sexual destiny beliefs are negatively associated with relationship satisfaction generalize to LGBTQ+ people. Using an online cross-sectional study design, participants (n = 685) were assessed on their sexual growth and destiny beliefs, compatibility, and relationship satisfaction using four measures. LGBTQ+ people did have lower sexual destiny scores than non-LGBTQ+ people, but the finding was so small that it is unlikely to be clinically significant; LGBTQ+ and non-LGBTQ+ people did not differ in levels of sexual growth belief. The interaction between sexual destiny beliefs and sexual incompatibility on relationship satisfaction generalized to an LGBTQ+ sample
Attachment style and texting with specific secure base figures
No full textThe present study investigated the relationship between anxious and avoidant attachment styles and texting behaviour, with attachment and texting being operationalized overall as well as broken down by specific kinds of attachment relationships. Participants, n = 90, were undergraduate students who reported on their texting behaviour over the previous 24 hours from their iPhone and they then completed the Experiences in Close Relationships – Relationship Structures questionnaire (ECR-RS) to measure adult attachment style. The results revealed that anxious attachment style with the mother figure was significantly negatively correlated with texting behaviour with the mother figure, and similarly, anxious attachment style with the partner figure was significantly negatively correlated with the texting behaviour with the partner figure. In other words, those who have an anxious attachment style to their mother and/or partner texted them less. Further, anxious attachment style with the mother figure was correlated with texting behaviour with the partner figure. On the other hand, an anxious attachment style with the father figure was not correlated with texting behaviour with the father figure. Significant relations between attachment style and texting were not found for non-attachment figures, and these relations held even when restricted to people who had actually texted with a partner during the 24-hour text period. The results suggest that mothers have a strong impact on their children's attachment style and texting behaviour with others, and that primary attachment figures are mothers and partners
The witch and the wife: female roles in Homers Odyssey, a reception study of Margaret Atwood's Circe/Mud Poems and the Penelopiad
No full textThis thesis will analyze Homer's characters Circe and Penelope as they appear in the Odyssey alongside the contemporary author Margaret Atwood's version of these two figures in Circe Mud/Poems (1971) and the Penelopiad (2005). Circe and Penelope are the only two figures who explicitly have sex with Odysseus in the Odyssey; despite this connection, they do not oppose each other in the Odyssey but are dichotomized in post-Homeric literature. I will show that Homer's Penelope is highly sexually alluring while Homer's Circe is not, despite her sexual relations with Odysseus. This thesis shows how post-Homeric literature and scholarship effectively desexualize Homer's Penelope and hyper-sexualize Homer's Circe. It also shows that Atwood's works do not participate in this dichotomy but are a return to Homer
Alterations in aerobic performance in female runners across phases of the menstrual cycle
No full textThere is a growing number of females participating in sport and reaching higher levels of performance. Although research around female physiology and menstrual cycles (MC) is a rowing field, the influence of MC phase on female athlete performance remains unclear. The study investigated the alterations in aerobic performance across the ovulation, mid-luteal, and menstruation phases of the MC in female runners. Through an observational repeated measures study design, five subjects monitored their MC timeline, using daily MC logs and ovulation testing (OVRY® Corduroy Enterprises Ltd), and MC symptoms across three MCs. Performance was measured using a 5km self-paced time trail during the mid-luteal, ovulation, and menstruation phases across two MCs, in which heart rate (HR) and rate of perceived exertion (RPE) were recorded. MC symptoms, motivation levels, and discomfort levels were measured prior to each performance test to compliment the quantitively performance values. Through a
one-way ANOVA with repeated measures, there were no statistically significant differences in performance found between ovulation, mid-luteal, and menstruation phases of the MC, F(2, 8) = 1.006, p = 0.408. Trends showed that subjects had a poorer performance during the menstruation phase when compared to the ovulation and mid-luteal phases. HR was 6.7 bpm lower at lap 5 of the performance test during menstruation compared to the ovulation phase. Subject's pace at lap 5 was 0.11 m/s slower during the menstruation phase when compared to the ovulation phase. These findings suggest performing aerobic activity during the menstruation phase may be more difficult and tailoring aerobic training to be completed during the ovulation phase may be beneficial for coaches to get the highest performance output from athletes
Developing eDNA primers for the monitoring and conservation of isoetes prototypus in Nova Scotia
No full textRare and elusive species often lack sufficient monitoring to efficiently carry out conservation efforts, and this is the case for the aquatic lycophyte Isoetes prototypus in Nova Scotia. This species is known from only 20 locations globally, 10 of which are in Nova Scotia. Due to the difficulties of accessing, identifying, and surveying this species, no monitoring has been conducted since 2004. However, eDNA analysis provides a solution to these challenges as it presents a simple, cost effective, and reliable alternative to visual surveys and physical monitoring techniques. The technique of eDNA also reduces uncertainty related to species identification as it is based on genetic sequences unique to that species, also known as DNA barcoding. This project involved conducting a series of surveys for I. prototypus in Nova Scotia
to establish a baseline of population changes since 2004, developing eDNA primers, and conducting a pilot study to test efficacy of this technique. The field surveys were carried out to the extent of the required scope of this project, and samples were collected for the remainder of the research. Methods were optimized to extract DNA from plant tissue, and primers were designed and tested for PCR amplification. Genetic sequencing revealed that the primers were amplifying the correct region and that they could reliably distinguish I. prototypus from other native Isoetes species. Extractions for eDNA analysis from positive control samples were analysed and the process is ready to be applied to samples collected from field sites. The eDNA protocols for this species have not been finalized, however, results suggest that with further optimization, eDNA will be a valuable additional tool for ongoing monitoring of I. prototypus
A bundle of joy or a ball of misery?: elucidating the relationship between parenthood, happiness, and savouring
No full textThe focus of the present study is examining the role savouring plays in explaining happiness differences between parents and non-parents. Seventy-seven participants over the age 18 were recruited through organizations and social media. They completed an online survey measuring their tendency to savour, and their level of positive affect and satisfaction with life. It was hypothesized that there would be significant mean differences among parent groups and savouring groups on positive affect and satisfaction with life, and an interaction effect between levels of savouring and parenting status. Data was analyzed using Pearson r correlations, and a two-way MANOVA. I found that savouring was significantly and positively correlated with positive affect and life satisfaction both in parents and non-parents, and both high and moderate savourers were significantly happier than low savourers
Comparing the thermal performance of mosquito immunity among species and life stages
No full textClimate change is affecting the global distribution of insect species and exposing them to new thermal environments. The immune system of insects is sensitive to temperature and is important for determining the outcome of infection. However, we have little understanding of how the immune system of different species and even life stages reacts to temperature. To help improve our baseline understanding of how temperature affects the insect immune system, my project objectives were: 1) to compare the immune performance of adult and juvenile life stages of lab-reared Aedes aegypti, and 2) to determine if temperature affects the immune system of different mosquito species in the same way, using wild-caught Culex territans, Culex pipiens, and Aedes japonicus as models. Melanization and encapsulation responses to Sephadex beads revealed high individual variation across species and life stages as well as robust responses mounted by larvae. Temperature had relatively little effect on the strength of responses by larvae, with most individuals mounting stronger responses relative to adults. Mortality rates in larvae following exposure to the fungus, Metarhizium brunneum, were significantly faster at 18°C. Higher temperatures (26°C and 32°C) increased the expression of the antimicrobial peptide defensin A in adults but did not impact expression in the larvae, potentially indicating different strategies mounted by different life stages when responding to pathogens. Of the three wild-caught species, temperature only significantly affected the performance of Cx. territans adults, but I observed differences in the strength of responses mounted by the different species, potentially due to varying life histories and investment strategies between the species. Differing responses mounted by different life stages and species indicate that we cannot make generalizable predictions about how the immune performance of different species or life stages will be impacted by changing thermal environments. This exemplifies the need to conduct further baseline studies to help understand the implications of shifting thermal environments for different insect species and how this will impact both terrestrial and aquatic ecosystems
Real-time REM sleep classification
No full textWe investigate and compare the ability of Convolutional Neural Networks (CNN) and Re-current Neural Networks (RNN) to classify Rapid Eye Movement (REM) sleep in real-time
using data from a commercial smartwatch.
iPhone and Apple Watch applications are developed that collect data from the Apple Watch sensors in real-time and store the data for model development and evaluation. Alternatively, this data could be provided to a model embedded in an iPhone app to classify the current sleep stage in real-time. Heart rate and acceleration data is collected and aggregated into 2-minute frames for input to the model. Ground truth data is also collected using interpreted polysomnography provided by a Cerebra Sleep Study system. Working with a psychology student at Acadia University we ran four sleep studies with four differentparticipants to gather data for our research.
Deep learning models are trained and evaluated using cross-validation on data from asingle subject, and then from multiple subjects. We conclude that a one layer convolution model with batch normalization and max-pooling and a recurrent model with two gated recurrent unit (GRU) layers perform the best overall. We recommend the double GRU model for it's higher true positive rate (TPR). The double GRU model achieved an AUC of 0.81, a correlation of 0.373, an accuracy of 77.3%, a TPR of 62.8%, and a TNR of 79% on the dataset from multiple subjects