MacEwan Open Journals (MacEwan University)
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The First Inventory of Katydids on the Osa Peninsula, Costa Rica
No full textThis study was undertaken to create the first inventory of katydids (Tettigoniidae) on the Osa peninsula, Costa Rica during the dry season. In addition to creating this first inventory we also collected data on environmental factors in order to allow for future comparison regarding patterns in katydid populations. We were able to sample 207 katydids using three different sampling methods and recording: time, temperature, humidity, GPS location, sex, and subfamily for each katydid found. We sampled three forest types: old growth, secondary, and riparian each three times. We organized each katydid with the help of our identification material first by subfamily and then by morphospecies using the photos we took of their distinguishing features. From this study we were able to come to the conclusion that our point sampling at night along a 200 meter transect was the most successful, as we collected data on 155 katydids using this method. We determined by our results that the subfamily Pseudophyllinae was the most abundant. Our inventory indicated that even during the dry season on the Osa peninsula it still showed a high diversity and evenness for these katydids based on our rank abundance graph. We have determined that this makes Osa peninsula an ideal location for sampling these insects, as there was such a healthy and stable katydid population.
*Indicates faculty mentor
Population dynamics of garlic mustard (Alliaria petiolata): A new invader to Alberta’s central parkland subregion
No full textGarlic mustard (Alliaria petiolata), a highly invasive biennial plant species, was first discovered in Alberta in 2010. It is present in two urban ravines in Edmonton and one in St. Albert. Introduced from Europe, this invasive species can be found in 37 US states and 7 Canadian provinces. This species rapidly invades forest ecosystems by dominating native vegetation. Garlic mustard is a threat to Edmonton’s River Valley due to its highly interconnected nature and the many native flora and fauna that inhabit this area. Understanding the population dynamics of an invasive species is critical to making informed management decisions. Previous research on the population dynamics of garlic mustard in other regions has reported high mortality in the first year and low second year mortality. The goal of our project was to assess garlic mustard mortality in its first and second year of growth within Edmonton’s central parkland subregion. To assess first year mortality fifteen 0.5 m2 quadrats were established in spring and monitored with biweekly counts over the first growing season in 2014 and 2015. To assess second year mortality fifteen 0.5 m2 quadrats were established in fall and then relocated in spring and monitored with biweekly counts over the second growing season in 2013-2014 and 2014-2015. Overall, first year mortality was 27% in 2014 and 2015 and second year mortality was 31% and 47%, respectively. This research will contribute to a broader understanding of the population dynamics of this species and may inform management decisions.
*Indicates faculty mentor
A Binaural Beamforming Approach to Resolve Complex Auditory Scenes for Humanoid Robots
No full textAwareness of the auditory scene dramatically enhances our ability to interact with the world, however many robots lack sound awareness. We present a novel approach to introduce sounds awareness to robotics by resolving complex acoustic scenes to determine the number of distinct sound sources and their approximate locations. Our approach utilizes the interaural time difference que in the implementation of recursive steered beamformer with a Bayesian updating step to create accurate auditory “map” of the space around the robot. The approach was implemented for the iCub humanoid and tested with up to five sound sources in free field. By first decomposing the scene spectrally and then taking advantage of the interaction between egocentric and allocentric auditory “maps”, we achieved localization accuracy within a few degrees and were able to resolve the sound sources with few errors.
* Indicates faculty mento
Complementation of hOLA1 in ychF E.coli
No full textHuman Obg-like ATPase 1 (hOLA1) is a protein that is expressed in human cells, and highly expressed in several cancer cells.. The study of hOLA 1 and its E. coli homologue YchF is important to gain a better understanding of their role within the cell, specifically the role hOLA1 serves in the cancer cells. Creating a simple vector for the expression of hOLA1 in ychF E.coli, will allow us to compare the functions of YchF and hOLA1 by competing the hOLA1 expressing cells with wild type E.coli. This was accomplished by the creation of a pBAC-hOLA1 plasmid that was transformed into ychF E.coli. These cells were found to be unable to compete with wild type cells. Further testing is required to demonstrate conclusively whether or not hOLA1 can replace the function of YchF in E.coli. This testing includes expressing hOLA1 genomically in E.coli under the natural promoter of ychF.
* Indicates faculty mento
Cardiorespiratory Responses During High Altitude Ascent to 5160m in Nepal: Relationships to Self-reported AMS
No full textIndividuals ascending to high altitude risk developing acute mountain sickness (AMS). The Lake Louise AMS scoring system is a self-reporting tool without quantitative physiological metrics. The purpose of this study was to assess cardiorespiratory acclimatization and AMS severity during an ascent to high altitude. A group of 20 participants trekked to 5160m over nine days in the Nepal Himalaya.
Cardiorespiratory variables were measured every morning following one night at each altitude, including oxygen saturation (SpO2; %), heart rate (HR; min-1), pressure of end-tidal (PET)CO2 (Torr) and respiratory rate (RR; min-1). These measures (delta from 1400m) were correlated with AMS scores during ascent at six altitudes (n=120). Correlations with AMS were as follows: SpO2, significant, moderate negative correlation (ρ=-0.35, PETCO2, no significant correlation (ρ=-0.16, P=0.08); RR, significant, weak negative correlation (ρ=0.24, P=0.008). However, an index combining these four variables ((HR/SpO2)*(RR/PETCO2)) vs. AMS revealed a significant, moderate positive correlation (ρ=0.48, P
* Indicates faculty mento
Terrestrial burrows represent low sea level events within the marine sediments of the Cretaceous Cardium Formation, Alberta
No full textDetailed core study of the Cardium Formation in west-central Alberta showed that terrestrial trace fossil (Taenidium) is present on a possible sequence boundary after a rapid sea level drop on a 4th- 5th order scale. The Cardium Formation represents the Western Interior Seaway during the Late Cretaceous, and provides evidence of several sea level fluctuations. Four wells were studied and total of 40m of core was logged from these wells. These cores demonstrated that terrestrial traces occurred above the regressive surface of erosion, during a period of relative sea level fall. A distinct pattern of mudstone being abruptly overlain by coarser sandstone was seen in the studied cores. The terrestrial trace (Taenidium) was found in the coarser and sandier marine sediments of the selected cores. The majority of the cored intervals contain marine traces including Zoophycos, so the presence of a terrestrial burrows suggests landward movement of the shoreline at that time. This example of terrestrial traces in the Cardium Formation helps to demonstrate that terrestrial traces can be used to help interpret sea level fluctuations in the rock record.
* Indicates faculty mentor
Modern calibration of biomarkers in the marine channels of the Canadian Arctic Archipelago using the PIP25 approach
No full textTwo lipid biomarkers, IP25 (a highly branched isoprenoid hydrocarbon; an ice proxy containing 25 carbon atom skeleton) and brassicasterol (phytoplankton derived biomarker), accumulate and become preserved in the marine sediments on the seafloor. IP25 is produced by sea ice algae (marine diatoms) while brassicasterol is produced by a suite of open-water algae (dinoflagellates, diatoms), allowing for determination of sea surface conditions in relation to sea ice conditions during accumulation. Absence of IP25 in marine sediments can indicate permanent sea ice coverage or absence of sea ice completely. High IP25 concentrations reveal sea ice conditions by which sea ice algae can thrive. High brassicasterol concentrations are an indicator of ice free surface conditions, whereas, an absence of brassicasterol would suggest sea ice coverage. Following extraction and quantification via Gas Chromatography Mass Spectroscopy, their respective concentrations can be related to each other in a ratio known as PIP25 (Phytoplankton-IP25 index) to reconstruct specific sea ice conditions (marginal ice zone, perennial ice cover, ice free, etc.). The PIP25 approach allows for currently accumulating IP25 and brassicasterol to be related to observed modern sea ice conditions, therefore providing a regionally appropriate calibration for the study of past conditions in the geological record. This study focuses on the modern calibration of these biomarkers in the marine channels of the Canadian Arctic Archipelago.
* Indicates faculty mentor
Does hysteresis in cardiorespiratory variables during high altitude ascent and descent quantify the magnitude of acclimatization?
No full textAcute mountain sickness (AMS) is common during ascent to high altitude. We aimed to quantify ventilatory acclimatization in the context of high altitude hypoxia by comparing oxygen saturation (SpO2) and end-tidal CO2 (PETCO2) during ascent and descent. We hypothesized
(1) the hysteresis area formed by differential cardiorespiratory values during ascent and descent would quantify the magnitude of acclimatization, (2) prolonged stays above 5000m would lead to larger areas than shorter stays, and (3) larger areas would be correlated with lower AMS symptoms. In 2012, a single male participant (P1) ascended to 5050m in Nepal and stayed approximately three weeks. P1 returned in 2016 as part of a group of 20 participants (P20), and stayed only one night above 5000m. In P1, the calculated SpO2 hysteresis area was 72% larger in 2012 than 2016. In P20, there was a weak positive correlation between SpO2 and PETCO2 hysteresis areas (r=0.43, P=0.06), but these values were not correlated with AMS severity when arriving above 5000m (r=0.06, P=0.8; r=0.3, P=0.2, respectively). We conclude that calculation of hysteresis in cardiorespiratory variables may hold promise as a simple method to quantify the magnitude of ventilatory acclimatization when staying at altitude for prolonged periods.
* Indicates faculty mentor
Mathematical modelling of the West African Ebola virus epidemic
No full textWe present a variant of the SEIR (susceptible-exposed-infectious-recovered) stochastic population-based compartment model of epidemiology to capture the spatial transmission dynamics of the Ebola virus disease epidemic in Sierra Leone, Liberia, and Guinea. Using registered data from the World Health Organization (WHO) situation reports we attempt to capture the transmission dynamics and the spatial spread of the Ebola epidemic. The projected number of newly infected and death cases are estimated and presented. Our objective is to achieve optimal Bayesian tracking of Ebola epidemic in both space and time with data that is (a) irregularly aggregated, and (b) only episodic in its availability. We use Ebola disease incidence as a posterior from the WHO reports. The ensemble optimal statistical interpolation (EnOSI) data assimilation method has been shown to produce optimal Bayesian statistical tracking of emerging epidemics (Cobb et al., 2014). We observe that the prediction improves as data is assimilated over time. The analysis thus provides a realization conditioned on all prior data and newly arrived data. We also found that EnOSI can efficiently adjust its estimated spatial distribution of the number of infected, if and when the epidemic jumps to a new city.
* Indicates faculty mentor
Foraminifera microfossils as a Proxy for Environmental Conditions in the Canadian Arctic
No full textForaminifera are microscopically small, marine organisms with a shell which preserves easily in the geological record. Therefore, they are used as prime indicators for environmental conditions such as temperature and salinity in both past and present settings. The project presented here aims to use foraminifera as a proxy for the environments of Arctic Canada. Sediment samples from and below the seabed were obtained during an expedition onboard the CCGS Amundsen icebreaker in Aug-Sep 2016. Aside from classifying the foraminifera populations, these samples will also be used for stable isotope analyses of oxygen and carbon, allowing for greater inference of overall environmental conditions both past and present. Results of this research will also contribute to an atlas of foraminifera for Arctic Canada.
Discipline: Earth and Planetary Sciences
Faculty Mentor: Dr. Anna Pieńkowsk