MacEwan Open Journals (MacEwan University)
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Phage Cd2 and Lactic Acid Bacteria, New Strategies in Food Safety and Quality Preservation
No full textLactic Acid Bacteria (LAB) play a key role in the food industry. They are essential for the production of fermented foods and they can also inhibit the growth of pathogenic bacteria, such as Listeria, since they naturally produce an array of antimicrobial peptides. However, certain species of LAB, such as Carnobacteria, are also associated with food spoilage. As such, the selective control of LAB is an important quest in the food industry. Recently, we is0lated bacteriophage cd2, a phage that selectively kills Carnobacterium divergens. To better understand the potential use of this phage for the biocontrol of C. divergens, we have examined its biochemical and genetic features. Our results indicate that phage cd2 is a virulent phage with an infection cycle of 70 minutes, is fully active across a broad pH range (4-12) and is heat-sensitive (fully inactivated by treated at 60oC). Genome sequencing and analysis shows that the 55 kb genome shares limited homology with several enterococcal phages, and likely encodes ~90 genes. Future work is focused on identifying and studying the mechanisms by which phage cd2 selectively recognizes and kills C. divergens.
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Muscle development and function in a Magel2 mouse model of Prader-Willi syndrome
No full textPrader-Willi syndrome (PWS) is a multigene disorder commonly associated with hyperphagia and obesity. Children with PWS have increased fat mass and decreased lean mass before the onset of hyperphagia and obesity. Severe hypotonia and reduced muscle strength are typically present in PWS infants. The process of autophagy is essential in maintaining musculoskeletal homeostasis, and increased or decreased autophagy can lead to muscle atrophy. Autophagic markers such as ubiquitin (Ub), p62/SQSTM1 (p62) and microtubule associated protein 1-light chain 3 (LC3) are hypothesized to be connected to the MAGE family of proteins that includes MAGEL2, suggesting that loss of MAGEL2 could modulate autophagy in muscle. Expression of Magel2 was detected in the murine nervous system and in developing muscle, connective tissue and bone. Immunohistochemistry (IHC), and immunoblotting were used to determine whether loss of Magel2 affects the accumulation of autophagic markers or expression of genes associated with muscle atrophy, in neonatal mice. The p62 positive aggregates were increased in muscle from magel2 mice and atrophy genes were up-regulated. Abnormal autophagic processes likely contribute to muscle atrophy in mice lacking Magel2. Further studies are needed to determine how the inactivation of Magel2 causes muscle phenotypes at a cellular level. Our mouse strain carrying loss of Magel2 provides a model for muscular dysfunction in Prader-Willi syndrome.
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Effectiveness of benzoyl peroxide application in the treatment of acne
No full textAcne is a skin condition involving the oil-producing glands in the skin that affects roughly 5 million Canadians. A common medication used to treat acne contains the organic compound benzoyl peroxide that works to remove acne causing bacteria in the epidermis. Benzoyl peroxide is an extremely volatile substance and, therefore, only constitutes 2% active ingredient of related acne care products. A multimedia fugacity model was used to determine the amount of chemical effectively emitted or absorbed into the skin. The parameters used in the model were set to fit a single application of medicated lotion to the face, with the non-aqueous phase liquid component being the sole receiver of the chemical. Assuming these parameters, it is estimated that 4.58x10-5 kg of benzoyl peroxide is deposited into the skin per application. The model demonstrates that humans are the main recipient of the chemical with over two-thirds being absorbed and the remaining is lost to the atmosphere through evaporation with negligible emissions to the water and soil environments. Since benzoyl peroxide is the most common chemical used to treat acne, it is important to determine how much penetrates the skin and the effectiveness of each application.
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The Effects of Osmotic Crowding on the Hydrolysis of p-Nitrophenyl Phosphate by E.coli Alkaline Phosphatase
No full textMost enzymes function in a very crowded environment within the cell. The kinetics of the enzymes have evolved to function under such conditions. However in most in vitro studies, enzyme kinetics are studied under comparatively highly dilute conditions. This experiment is designed to study the hydrolysis p-nitrophenyl phosphate catalyzed by E.coli alkaline phosphatase using osmotic crowding to simulated in vivo conditions. The results of this experiment will be compared to our previous studies using calf intestinal alkaline phosphatase. Ultimately, these experiments will help us better understand the behavior of drugs under more cell-like conditions, allowing for better drug design and testing.
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Associations of personality and substance use
No full textSubstance use, for the purpose of this study, has been defined as the non-medical use of substances (tobacco, alcohol, cannabis, cocaine, amphetamines-type stimulants, inhalants, sedatives or sleeping pills, hallucinogens, and opioids). Although there are several personality theories as to why individuals engage in substance use, there has yet to be a study conducted looking at correlations between substance use and the HEXACO model of personality. Previous research has indicated associations between substance use and personality, such as cocaine use being correlated with Extraversion and Openness to Experiences. It has also been shown that an individuals’ confidence in recovery rate correlated with higher scores in Agreeableness, Extraversion, and Conscientiousness. However, these previous studies used inconsistent and outdated personality measurements and definitions of substance use. Our study examines whether or not certain personality traits are associated with substance of choice. We used various social media outlets to administer the HEXACO Personality Inventory, a modified version of ASSIST, and the PHQ-9 on a sample of 291 individuals. Participants ranged in age from 17 to 64 and lived across North America. Along with correlating personality traits and substances, this study looked to measure personality traits in relation to seeking treatment. Results indicated statistical significance between individuals who used the same substances with Honesty/Humility and Conscientiousness, and no statistically significant correlations with treatment and personality traits. Although research in this field is not relatively new, it is important to replicate studies with up-to-date measurements in order to gain the most accurate measurement of possible correlations.
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Comparing depositional environments and porous zones in the 400 million-year-old sabkhas of subsurface Alberta
No full textUsing subsurface core and well logs, a comparison of sedimentary deposits in evaporite-containing formations of the Devonian hypersaline seas of Alberta was done. Thin sections from the Nisku Formation were examined using a petrographic microscope to determine how and when brine and hydrocarbons moved through two porous zones, identified by well logs from the same area. These two zones within core and thin sections were compared with other zones from which only well logs were available. Through measurements of the porosity, permeability, and timing of diagenesis from petrography, it is determined that areas of high neutron and density log responses correlate with cemented zones within the core. This research has a direct impact on the understanding of how evaporitic facies can cause different responses within well logs. Our understanding of how well logs, accompanied by core and thin section analysis, can give insight into the movement of fluids and gases in subsurface Alberta is also aided.
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MRU active office study: Is there a relationship between cognitive function and neurovascular coupling?
No full textNeurovascular coupling (NVC) is the matching of local cerebral blood flow to neuronal activity. NVC magnitude may be linked to cognitive performance (CP). We aimed to determine the relationship between NVC and CP, using tests designed to asses working memory (Digit Span; DS) and executive function (Stroop). We hypothesized that individuals with larger NVC responses would have increased working memory and executive function test scores. Participants (41.2±1.3yrs; n=62; 12 males) were recruited as a part of the MRU Active Office Study. Participants were instrumented with transcranial Doppler ultrasound for posterior cerebral artery velocity (PCAv) in a seated position, and underwent a 3-min eyes closed baseline prior to an NVC test with a strobe light (6Hz; 30sec on/off x5). Participants then performed the cognitive tests on an iPad. Peak PCAv from baseline
( P) and slope (
P/ T) were calculated during the NVC test. There
was no correlation between DS test performance and
P (r=-0.07,
P=0.62) or P/
T (r=0.03, P=0.8). There was no correlation between
Stroop test response time for P (r=-0.1, P=0.47) or
P/ T (r=-0.09,
P=0.48). These preliminary results suggest that there is no functional link between NVC magnitude and CP in a large group of MRU employees.
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Inter-institutional collaborative chemistry assignments
No full textTo help students learn the disciplinary language of chemistry, disciplinary communication was set up between chemistry learners who are in their first organic chemistry course at the University of Illinois Springfield and Mount Royal University. Students were assigned a series of organic compounds or reactions that they must describe using IUPAC nomenclature and correct chemical terminology to their partner at the other campus. The partners would then interpret the description provided to them and sketch the appropriate chemical representation. The students are then encouraged to discuss if the drawing is correct and if not, where the misunderstandings lie. We will discuss how instructional technologies were used to foster a valuable experience between learners from different campuses. An overview will be provided that shows different types of problems students worked on with their partners and model how they exchanged information. Successes and difficulties in integrating the interinstitutional collaborative assignments will be presented as well as how some difficulties have been addressed and future development needs.
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Models of Generalized Anxiety Disorder: Does The Emotion Dysregulation Model Aid Understanding?
No full textWhile models of generalized anxiety disorder (GAD) are available, the literature continues to explore and expand upon the different conceptualizations. Among these models, one of the most recent is the Emotion Dysregulation Model (EDM). According to the EDM, individuals with GAD have issues understanding, expressing, and managing emotions. The EDM proposes that individuals with GAD experience the following: emotional hyperarousal, involving low emotional thresholds; poor understanding of emotions, including problems with describing and labelling; negative attitudes towards emotions; and unsuccessful emotion regulation and management strategies. However, there is a lack of research providing support for the utility of the EDM. Furthermore, a gap exists in the literature comparing the EDM to more established models. The proposed study extends the current literature by examining whether the EDM helps explain GAD symptoms when compared to a well-established model of GAD, the Metacognitive Model (MCM). The MCM emphasizes that individuals with GAD have negative beliefs about the dangerousness and uncontrollability of worry. Several self-report measures previously used in research of the EDM and the MCM will be administered to non-clinical university participants (N = 400) to investigate which measures uniquely predict GAD symptoms. The proposed study hypothesizes the following: GAD symptoms will positively correlate with emotion dysregulation; GAD symptoms will positively correlate with negative beliefs about worry; and emotion dysregulation will predict GAD symptoms independent of negative beliefs about worry. Expected findings have implications for treatment of GAD, encouraging an approach focusing on emotion psychoeducation and development of effective emotional regulation strategies.
Discipline: Psychology Honours
Faculty Mentor: Dr. Alexander Penney 
Behavioural Interventions for Sleep: Who Prefers what?
No full textMany university students have trouble sleeping because their minds are too active with worries and other sleep disruptive thoughts they are unable to control. Previous research has compared two self-help intervention: Structured Problem-solving, which involves scheduling time earlier in the day to write out worries and steps toward solutions; and Beaudoin’s Somnotest APP, which uses mental imagery to prevent sleep disruptive thoughts. Both interventions were equally effective alone or in combination. Nevertheless, there were individual differences in how students responded to the interventions. Our study extends previous research by examining these individual differences. We examined students’ preferences for interventions in relation to their circadian preference (morning types and evening types) and their preferred way of coping with stress (i.e, emotion focused vs. problem focused). We predict that students who prefer problem-focused coping will also prefer Structured Problem-solving, whereas those who prefer emotion-focused coping will favour the APP. Since evening types take longer to fall asleep, we predict that they may find the APP less effective because it could be arousing. Participants consisted of 131 MacEwan University students who were poor sleepers. They completed standardized measures of sleep and arousal (Sleep Quality Scale, Glasgow Sleep Effort Scale and Pre-Sleep Arousal Scale), ways of coping with stress (COPE) and circadian preference ( Composite Scale of Morningness). Data analysis will be completed by April. Results and implications will be discussed.
Discipline: Psychology
Faculty Mentor: Dr. Nancy Digdo