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HARVEST

University of Saskatchewan's Repository for Research, Scholarship, and Artistic Work

Welcome to HARVEST, the repository for research, scholarship, and artistic work created by the University of Saskatchewan community. Browse our collections below or find out more and submit your work.

 

Recent Submissions

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Microbial Decontamination of Egg Surface via Cold Plasma
(2024-03-18) Movasaghi, Mina; Zhang, Lifeng; Schwean-Lardner, Karen; Kirychuk, Shelley; Lin, Yen-Han; Zhang, Haixia
Eggs and egg products are widely consumed worldwide. In North America, eggshells are cleaned to eliminate contamination by microorganisms such as Salmonella and Escherichia coli. The most common commercial decontamination method in the egg industry is washing eggshells with hot water and a chemical solution. Egg washing reduces the bacterial load, however, the use of chemicals can produce a considerable amount of chemically contaminated wastewater. More recently, cold plasma or non-thermal plasma has attracted global attention as an emerging non-thermal technology for food decontamination. Cold plasma is an emerging green technology‎, generating several reactive species that can be used effectively for microorganism inactivation and is attracting global attention for food safety purposes. Investigating the application of this technology as a chemical-free and non-thermal approach for decontaminating egg surfaces‎ and assessing its potential as an alternative to the conventional method of washing eggs was the primary objective of this study. For optimizing the process, various operation conditions of a cold plasma jet device were examined to decontaminate eggshells inoculated with Escherichia coli and Salmonella.‎ The different operating variables, including the distance between the nozzle and egg surface (1, 2, or 3 cm), device power ‎‎(300, 350, or 400 W), gas flow rate (30, 32.5, or 35 l/min), feed gas (air, N2, He and air mixture), relative humidity of the feed gas (20%, 40%, 65%), and exposure time (20, 40, or 60 s)‎ were examined in the study. To evaluate the potential impact of cold plasma on egg quality, different properties such as eggshell thickness, specific gravity, albumen pH, Haugh unit, yolk index, moisture content, and qualitative analysis of the egg albumen and yolk were measured after the treatment with cold plasma. The results showed that 60 seconds of direct exposure time resulted in the optimal cold plasma operating conditions that led to the highest deactivation percentage for bacteria inoculated on the egg surface included an air (RH=65%) flow rate of 35 l/min, a distance of 1 cm, and a power of 400 W. At these conditions, the system achieved a maximum reduction of 1.94 log CFU/egg and a deactivation percentage of 98.64 % for E. coli and 92.20 % deactivation percentage with a 1.11 log reduction for Salmonella. Statistical analyses of the physical properties of treated eggs showed that there was no significant difference in physical properties between the cold plasma-treated eggs and the control eggs (unwashed and washed eggs) when measured one week after the treatment. The intensity of protein bands of SDS-PAGE gel image was analyzed, and the results indicated that there was no significant variation in protein content between the three sets of eggs (cold plasma-treated, washed, and unwashed eggs). The research has demonstrated that cold plasma jet can be used as a promising and environmentally friendly method for decontaminating eggshell surfaces. However, the study was limited in scale, and further investigations are required to scale up and apply the cold plasma system for large-scale commercial applications.
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COMPASSIONATE SPORT BODIES: EXPLORING RACIALIZED YOUNG WOMEN ATHLETES’ INTERSECTING IDENTITIES AND BODY-RELATED SPORT EXPERIENCES
(2024-03-15) Eke, Abimbola O; Ferguson, Leah J; Erlandson, Marta C; Humbert, Louise M; Martin, Stephanie L; Williams, Toni
Body image is an important part of women athletes’ sport experiences. The perception of one’s athletic body may be different for people of racialized backgrounds playing sport in Western society. However, body self-compassion, a kind and non-judgemental attitude towards one’s body, has been linked to more positive body image. My research program comprised of three interrelated studies aimed at exploring the body-related sport experiences of racialized young women athletes in Canada. In Study 1, I focused on the identity and body-related sport experiences of racialized young women athletes. Employing a qualitative description strategy of inquiry, Study 1 involved eight racialized young women athletes (ages 14–18 years), who engaged in one-on-one interviews and reflexive photography. A reflexive thematic analysis identified three overarching themes—(a) Who I am vs who they say I am; (b) My unique body in sport; and (c) The importance of representation. Through reflexive thematic analysis, I identified that intersectionality, discrimination, and diversity are critical factors influencing the quality of sport experiences for racialized young women athletes in Canada. Building upon Study 1, Study 2 focused on body self-compassion, exploring its potential benefits for racialized young women athletes in sport. This study involved eight racialized young women athletes (ages 14-18 years), adopting semi-structured one-on-one interviews and reflexive photography. Following a reflexive thematic analysis, three themes were developed—(a) Representing my racialized body authentically; (b) Accepting my racialized body for performance; and (c) Understanding the attitudes and emotions about my racialized body. Despite the unique challenges racialized young women athletes may have in sport, my findings in Study 2 suggested that body self-compassion fosters body acceptance, emphasizing the importance of promoting a compassionate approach to the body in sport for a more inclusive and accepting environment. Study 3 took a narrative approach, exploring the practical application of body self-compassion with seven racialized young women athletes (ages 13-18years). Using focus group discussions and body mapping, this study developed three overarching narrative themes—(a) Racialization and compassion; (b) The importance of compassionate support systems; and (c) Culture, religion, and sport. Presented through creative non-fiction, Study 3’s findings, represented through five portrait vignettes, demonstrated how body self-compassion can nurture a focus on function. This study highlights that for athletes navigating the complex intersections of racialization, cultural backgrounds, and religious beliefs, body self-compassion could help foster a more positive body image. Collectively, my studies contribute valuable insights to the understanding of the sports experiences of racialized young women athletes, advocating for a more inclusive and compassionate approach that honors their multifaceted identities within the sport context.
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Master Thesis
(2024-03-15) You, Yun; Samuel, Butler; Igor, Morozov; James, Merriam; Artur, Sowa
With a given fixed array of electrodes, a very large number of four electrode measurements can be made. However, most of the possible measurements are not linearly independent, indicating that a smaller number of measurements can be made in order to save time, and the results of other measurements can be calculated later. In some cases, this calculation process can amplify measurement errors and so a robust quality control criterion is needed. In the past, it has been demonstrated that pole-pole, pole-dipole and pseudo-pole-dipole data can be used as a basis for calculating other measurements. In this study, we consider pseudopole- pole datasets as a basis. We define a pseudo-pole-pole array as one in which there is always a fixed current and potential reference electrode, but these reference electrodes are not necessarily far from the rest of the measurement array. We show that all four-electrode measurements can be easily calculated from pseudo-pole-pole data in ways that are similar to pole-pole data. We additionally show that good quality pseudosections and inversion results can be recovered from transformed data from pseudo-pole-pole data, especially for transformed data in configurations similar to the Wenner-α array. We also show that independent normal and reciprocal four electrode measurements can be calculated for each four electrode array and the comparison of these can be used as a quality control criterion.
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Empirical Study and Modelling of Leaf Surface and Angular Optical Properties
(2024-03-15) Peters, Reisha D; Noble, Scott D; Tabil, Lope; Bueckert, Rosalind; Baik, Oon-Doo; Bourassa, Adam; He, Yuhong
Leaf optical property modelling is a tool that has been used for many decades to describe the interactions of light with plant leaves. Using these tools, measurements of light reflected and transmitted from plant leaves can be used to estimate the biochemical and biophysical properties remotely. Light in the ultraviolet, visible, and near infrared regions of the spectrum is affected by different biochemical components within the leaf sample and the biophysical properties have the potential to affect the whole wavelength spectrum. Furthermore, the angle of illumination and observation affect both the spectral shape and intensity of the reflected and transmitted light spectra. Some of the most widely used leaf optical property models use spectral data that do not describe the angular components of reflectance and transmittance. While this simplifies the model and results in a more predictable spectral result from defined biochemical parameters, it is difficult to apply this model to field data. The data used in these models requires hemispherical measurements of reflected and transmitted light whereas data collected in the field are typically limited to single angle with variable illumination angle and polarization. These single angles are not always representative of the hemispherical spectra expected by the model and are affected to a greater degree by the biophysical attributes of the leaf. In this work, an extension to the PROSPECT-D leaf optical property model was developed to combine the effective hemispherical modelling developed by previous researchers with the spatial component that is related to the angular measurements obtained in a field setting. This was done by connecting physically measured attributes of plant leaves to the spatial distribution of the reflected spectra. Through the course of this work, it was hypothesized that the modelling capabilities could be further improved by calibrating the model with a more diverse and agriculturally-based calibration dataset. However, it was found that the approach to this problem may be better aligned with calibrating the model with species specific datasets for targeted applications. In short, a one-size-fits-all model may not be the best solution to improve biochemical and biophysical parameter acquisition using leaf optical property modelling.
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Global Water Futures Observatories : a solutions oriented network of world class observation sites and laboratories
(2024-03) DeBeer, Chris
Global Water Futures Observatories vision, principles of operation, and Priority Research Support Directions 2023-2029.
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Jigging our Health
(2024-03-05) Mainra, Nisha; Foulds, Heather; Oates, Alison; Lovo, Stacey; Marks, Wendy
The Red River Jig (RRJ) is a traditional Métis dance practiced among Indigenous and non- Indigenous Peoples. Though exercise benefits physical health and fitness, the benefits of cultural dances to improve wholistic aspects of health are less clear. This study aimed to investigate social, psychosocial (cultural and mental), physical function, and physical fitness benefits of participation in an RRJ intervention. Indigenous and Non-Indigenous adults (N=27,38±14 years, 20 females) completed an 8-week RRJ intervention. Social support index, multigroup ethnic identity measures of cultural connectedness, and mental well-being questionnaires, as well as seated blood pressure and heart rate, weight, grip strength, six-minute walk test, and one-leg and tandem balance measures were assessed before and after the intervention. Cultural connectedness and mental well-being scores were similar before and after the intervention. Community components of social support scores (7.7 ± 1.4 vs. 10.3 ± 1.4, p<0.001), six-minute walk test distance (551.5 ± 96.6 m vs. 581.3 ± 100.8 m, p=0.002), and tandem eyes closed balance (86.0 ± 45.9 s vs. 102.8 ± 31.9 s, p=0.02) increased after the intervention. Seated systolic blood pressure (117.6 ± 6.1 mmHg vs. 112.9 ± 10.8 mmHg, p=0.02) and heart rate (62.2 ± 6.3 beats·min -1 vs. 59.8 ± 5.6 beats·min -1 , p=0.02), weight (80.6 ±23.1 kg vs. 79.4 ± 23.2 kg, p=0.04), and one leg eyes closed balance (26.0 ± 17.2 s vs. 22.6 ±16.3 s, p=0.04) decreased after the intervention. A RRJ intervention can improve social support, physical function, and physical fitness for Indigenous and Non-Indigenous adults. (Funding: Saskatchewan Health Research Foundation)
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Language and Acculturation Among Iranian Immigrants in Canada
(2024-03-12) Davoodizadeh, Fatemeh; Makarova, Veronika; Li, Zhi; Cenerini, Chantale
Since Canada is one of the world’s major recipients of immigrants and refugees, their social accommodation remains one of the priorities in immigrant studies, bilingualism studies, and immigrant language research (Green & Worswick, 2017; Picot, 2008). However, since the cultural and linguistic accommodation needs differ by the group of immigrants, it is essential to increase the diversity of ethnic groups in the scope of research (Shea et al., 2022). More specifically, linguistic and acculturation experiences of Persian-speaking immigrants in Canada have been under-investigated despite a steady increase in the population of Iranian immigrants in Canada over the last decade (Rahnama, 2020). This study investigates how Persian-speaking immigrants adjust to life in Canadian society, acquire English, and whether they are preserving their heritage culture and maintaining the Persian language. The research is grounded in bilingualism and multilingualism theory (Lorenz et al., 2023), as well as in the bidimensional model of immigrant acculturation theory (Berry, 1997). The study adopts a mixed methodology based on a descriptive and quantitative analysis of survey responses and a qualitative analysis of interviews with participants. The study thus falls into “Explanatory Design” (Creswell, 2006, p. 37) informed by Model 4 of Steckler et al. (1992) classification of mixed methods designs in which qualitative and quantitative methods are used equally and in parallel. The results of the present study are based on the responses of 67 participants (age group of 18 years old and above) who spoke Farsi as the first language and also had some knowledge of the English language. The analysis of survey questions was conducted using Chi-square test and Kruskal-Wallis tests by rank. The participant responses to interview questions were first transcribed using Otteri.ai, and the analysis of interview responses was conducted through thematic analysis with NVivo software. The findings demonstrate a significant increase in the participants’ perceived importance of maintaining Persian language over time of immigration (at the time of immigration and at the time of the study), whereas the importance of acquiring English skills remains relatively stable. Proficiency in English emerged as a key factor in employment opportunities. Furthermore, bilingualism in English and Farsi was found to play a critical role in shaping and enriching the participants’ social interactions. iv The participants also suggested several measures that the government could apply to facilitate the integration of newcomers in Canada. These suggestions include organizing social events and gatherings where immigrants can interact and share their culture, government sponsored language training programs to help immigrants improve their English or French skills and offering other government programs and services for newcomers. Additionally, the development of Persian language learning programs in education was identified as a valuable strategy for preserving the Persian culture, which the government could facilitate. The current study extends the understanding of acculturation among Persian-speaking immigrants in Canada, offering insights that could be helpful in developing a more supportive and welcoming environment for newcomers.
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Advancing Design and Fabrication of Microfluidic Devices for Biomedical Applications
(2024-03-12) Tony, Anthony; Zhang, Chris; Badea, Ildiko; Oguocha, Ikechukwuka; Chen, Li; Bugg, Jim; Chen, Daniel; Selvaganapathy, Ravi
Applications of engineering methods to biology have grown with a desire to build devices for integrating various tests on cells, called Lab-On-a-Chip (LOC), and for mimicking biological systems, called Organ-On-a-Chip (OOC). Such devices have “small” channels (around micrometer to nanometer) and manipulate “small” amounts of fluids to flow (typically micro-litre, nano-litre up to milli litre) and therefore are called microfluidic devices. While LOC is useful for diseases diagnosis, OOC goes much beyond, not only for the improved capability of diseases diagnosis but also for drug development at cellular levels, as well as research into more understanding of cellular behaviours, by providing a biomimetic environment for cells, including the facility of stressing cells. There is no doubt that the OOC technology is a disruptive one to biology and medicine. Due to the need of high compatibility (chemical, physical and biological) with LOC and OOC, polymer materials are usually employed. This thesis aims to advance the technology of design and fabrication of (polymeric based) microfluidic devices of both LOC and OOC for biomedical and healthcare applications. This thesis conducted four specific studies. The first study aims to advance our understanding of the additive manufacturing (AM) technology with the material of polydimethylsiloxane (PDMS). This is achieved by categorizing and classifying all AM processes in literature. As a result, AM processing of PDMS is divided into two categories, namely (1) direct approach and (2) indirect approach. The literature in both categories was critically reviewed, leading to the identification of five knowledge gaps. The study also presented the author’s preliminary experiment on the indirect approach, printed mold approach in this case. Specifically, the experiment leads to the finding of the optimal post heat treatment of the mold for PDMS casting for the material of Full cure835 Vero white plus, namely (1) the heat treatment of the mold at 65° C for a time duration of 4 h and overnight cooling, followed by (2) oxygen plasma treatment at 50 watts, 45 millitorrs of O2, for a time duration of 30 s and (3) silanization of mold for a time duration of 1 h, and (4) casting of the PDMS and curing it under room temperature for curing at 24 °C) for a time duration of 24 h. The second study concerns bonding of two polydimethylsiloxane (PDMS) parts, an important step to construct PDMS microfluidic devices. Two main requirements on the bonding are such that (1) the bonding strength is as high as possible, and (2) the alignment of two parts is as accurate as possible. The study developed a simple yet effective bonding process for PDMS-to-PDMS using isopropyl alcohol (IPA). Specifically, the process aligns two PDMS parts and adheres them with IPA prior to the plasma treatment and subsequent post treatment of the assembly, followed by natural curing of the assembly. The result with this process significantly improves bonding strength from 1.9 MPa (the best bonding strength reported in literature) to 3.060 MPa. The mechanism behind this improved performance with the proposed process is also proposed in this study. The study can conclude that the proposed bonding process is very promising in the bonding of two PDMS parts with high strength as well as the potentially improved accuracy in alignment of two PDMS parts. The third study concerns the development of a biocompatible OOC, which is capable of (1) programmable stretching of cells in the X, Y, Z directions (3D stretching in short), (2) generation of static, cyclic, and randomized stretching forces to cells, (3) nutrients transfer, and (4) wastes discharge. Design as well as fabrication of such an OOC made from PDMS is a challenge. In this study, the OOC was designed to have three layered modules (top, middle, bottom) with each having a chamber. The middle module and the bottom module are separated by a porous membrane, so the chamber of the middle module is on the top side of the membrane, and the chamber of the bottom module is on the bottom side of the membrane. The middle module, porous membrane, and bottom modules are bonded together. Cells are anchored upon the top side of the porous membrane, and they reside in the middle chamber, while the nutrients and wastes are inside the bottom chamber. Four ports (two along the X direction, the other two along the Y direction) surround the middle chamber and bottom chamber, respectively, and these ports are filled with the air. By regulating the air pressures inside these ports, the side walls of the chambers deform in the X and Y directions, so does the porous membrane, thereby resulting in the stretching of cells in the X and Y directions. The top module is responsible for the stretching of cells in the Z direction by regulating the air inside its chamber to deform its bottom part, thereby generating the pressure on cells along the Z direction. All these modules were made from PDMS, and they were fabricated using the printed mold approach. In this study, the preliminary experiment was performed on (1) the deformations in the X, Y, and Z directions, (2) the programmability of these deformations, and (3) characteristics of the deformations (static, cycle, randomized). By preliminary it was meant that the quantitative measurement and assessment of the deformation response of the device were not attempted. The result of the experiment showed that the foregoing requirements were satisfied with however one problem, that is, the bonding of the porous membrane with the middle module as well as bottom module is weak in terms of fatigue strength. The study can conclude that (1) the developed OOC has a potential to meet the requirements and (2) the problem of weak bonding needs to be addressed and a potential solution may be to use a stronger bonding process or to change the design of the interface structure between the porous membrane and the middle or bottom module. The fourth study concerns the so-called sliding microfluidic device. The main challenge with such a device was in the interface of two components which can perform a relative sliding motion. This challenge was addressed by a new design concept called a “step” structure. This structure also eliminates the need for putting “chemical lubricant” on the interface to prevent leakage, which was used extensively in literature. Another challenge was the difficulty to fabricate a high aspect ratio step structure by using the traditional lithography approach. The study found that the AM technology can overcome this difficulty. The developed devices was tested for sorting poly(vinyl alcohol) (PVA) particles, which were regarded a good substitute of real cells in literature. The study can conclude that (1) the design concept of the step structure is valid, and (2) the sorting accuracy (85%) can be achieved, which was excellent at that time. Overall, besides the specific conclusions drawn in each of the four specific studies, this thesis has the following general conclusions: First, the current AM technology can build PDMS microfluidic devices to meet the requirements of OOC. Second, there is room to further improve the functionality of the PDMS microfluidic device by improving the fabrication technology, including the AM and the development of new materials that possess the merits of PDMS but with improved manufacturability by AM.
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Intersections of Historical Consciousness: The Meeting of Indigenous and Settler Histories in Canada’s Storied Places
(2024-03-11) Desveaux, Michelle; Carlson, Keith; Handy, Jim; Korinek, Valerie; Bidwell, Kristina; Campbell, Claire
The abstract of this item is unavailable due to an embargo.
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Characterization Of Chemical, Nutritional, And Techno-functional Properties of Protein-rich Fractions Obtained From Canola Cold-pressed Cake
(2024-03-08) Majumder, Dipika; Wanasundara, Janitha; Nickerson, Michael T; Tanaka, Takuji; Vujanovic, Vladimir; Ghosh, Supratim
The present study explored proteins of canola cold-pressed cake (CCC) for value-addition prospects. The protein and fiber fractionation developed by Agriculture and Agri-Food Canada (AAFC) was applied to CCC as-it-is (N-CCC) and after de-oiling with ethanol (E-CCM) or hexane (H-CCM). De-oiling with hexane and ethanol provided < 1% oil containing meal with protein levels of 40.6% in E-CCM, 35.4% in H-CCM compared to 31.1% in N-CCC. The fractionation generated two protein-rich and three fiber-rich fractions of each meal. The napin protein isolates (NPI) had the highest protein content (96.2%-97.9%) followed by cruciferin protein concentrates (CPC) (55.3%-74.2%) and intermediate protein fractions (IPF) (25.2%-29.7%). The soluble sugar rich fractions (SSF), and seed coat fractions (SCF) had 15.0%-16.3% and 21.4%-24.7% protein, respectively. These fractions recovered 99.8%-99.9% of total meal dry matter and 102.4%-102.7% of starting meal protein. Total phenolic content (TPC) was found to be 1.3-1.4 mg/g in N-CCC, E-CCM, and H-CCM, and NPI from N-CCC showed higher TPC than the other fractions. De-oiling did not affect meal phytate content (2.5-3.0 g/100g). The IPF of all meals had higher phytate values (15.3-19.3g/100g) than other fractions. The amino acid composition of the meals and their respective protein fractions followed their signature compositions. The presence of napin and cruciferin in NPI and CPC, respectively was confirmed. Selected functional properties of NPI and CPC of all three meals were studied. Proteins of NPI gave solubility values of 80-100% at pH 4.0, 7.4, and 9.5, regardless of the meal origin while CPC had values between 14-59%. The surface hydrophobicity values and negative zeta potential values of proteins in CPC were larger than NPI. Both NPI and CPC of all meals had higher oil holding capacity than commercial soy protein isolates at the same protein level but lower water holding capacity for CPC (<2.2 g/g protein). NPI emulsified more oil than CPC under the conditions of 0.5 M NaCl, and 10% sucrose, regardless of the meal origin, however, the stability of formed emulsions was similar. NPI of ethanol de-oiled meal exhibited better foaming properties at pH 4.0 than N-CCC with a foam capacity and stability similar to commercial whey protein isolate at equal protein level. The proteins of NPIs showed denaturation temperatures that aligned with constituent proteins and denatured completely at ~100ºC. The AAFC meal fractionation process can successfully be applied to CCC with or without defatting to obtain highly pure NPI, however, product composition and functional characteristics of CPC fraction depend on the residual oil that is portioned from the meal. This process allows obtaining protein-rich products from CCC with unique protein types and functional properties.