StFX Scholar (St. Francis Xavier University)
Not a member yet
55051 research outputs found
Sort by
Solidification properties of mixed disaccharides and amino acid solutions
No full textCryopreservation of living cells and tissues has revolutionized the areas of plant and animal breeding programs, cell banking, biotechnology, and modern medicine. The protective agents known as cryoprotectants are used in the freezing process to prevent any internal damage to the biological configuration of the material due to freezing. Polymers, proteins, amino acids, sugars, polyhydroxy compounds, and amines, are some commonly known types of cryoprotectants found in nature. Since the establishment of the cryoprotective effect of glycerol, cell banking has become routine in many areas of biotechnology and medicine. Despite being so helpful in day-to-day life for various applications there are some limitations such as toxicity (when used in excess amounts) of these traditionally used cryoprotectants that cannot be neglected. This study will help to provide a safer variety of options for cryoprotectants to choose from. In this experiment, some already known cryoprotectants such as disaccharides and amino acids were chosen and mixed in six different concentrations (1, 5, 10, 20, 30, and 40 wt%) in three different wts% each i.e., 50-50%, 75-25%, and 25-75%. Each mixture is then cooled to a sub-zero temperature in differential scanning calorimetry (DSC) to analyze their ability to reduce ice formation from their melting thermograms. The cooling rate during the experiment was kept at a high rate to promote amorphicity, while heating rates were kept slow enough to measure melting enthalpies accurately. DSC used in this experiment was calibrated using standard procedure. The results obtained from the experiment are then discussed in two sections: a) amorphicity comparison among pure solutions, and b) amorphicity comparison among mixed solutions in all three ratios to pure solutions. The results indicate that both amino acids and disaccharide solutions follow a similar downward trend in amorphicity with an increase in concentration among solutions. Comparisons among the ix behavior of lysine, proline, arginine, and disaccharides (sucrose and trehalose), suggests that lysine shows the highest propensity for amorphicity, contrary to the expectations based on the Kyle and Dolittle hydrophobicity scale. On the other hand, in mixed solutions, a detailed analysis of the amorphicity behavior of various solute combinations in aqueous solutions is also provided. It concludes that the crystallization among aqueous solutions of mixed solutes depends upon various factors, such as, solute-water interactions, solute-solute interactions (self-aggregation), synergistic or anti-synergistic approach of amino acid and disaccharide mixture, and diffusion and molecular properties of solutes. It is observed that, unlike lysine, both arginine and proline display self-aggregation of molecules as soon as their concentration increases in solution. Among three different combinations of solutes i.e., 50-50%, 75-25%, and 25-75% solutions it is also observed that a 25-75 % mixed solution can reduce the amorphicity to a greater extent even though the total amount of solute used in each mixture was similar. Therefore, amorphicity was considered to not only depend upon the amount of solute present in the solution but also on the nature of interaction with their surrounding molecules. Also, the difference in amorphicity values observed between trehalose and sucrose in combination with lysine, as well as the differing effects of proline/arginine on these sugars, suggest complex interactions influenced by their individual properties and their impacts on water structure and molecular aggregation. Continued research in this area has the potential to further refine and optimize cryoprotectant formulations for a wide range of uses. Furthermore, investigating the performances of these cryoprotectants under various freezing conditions can provide valuable insights into their practical applications
The life and musical voice of Tom Harrell
No full textThe jazz trumpet tradition carries back to the turn of the 20th century with artists such as Buddy Bolden, Louis Armstrong, and Bix Beiderbecke. As time passed towards the mid-century, innovators including the names of Dizzy Gillespie, Fats Navarro, and Clifford Brown were pioneering the next era of jazz that would change the music forever. ‘Bebop’ quickly became the style of jazz that took over the scene in the 1940s and would alter the course of jazz music to come. After the release of Miles Davis’s album Kind of Blue, the modified, more melodic style ‘hard bop’ would become the new most popular style across America. Tom Harrell would find himself growing up in the ‘hard bop’ era and would utilize various influences from the deep history of jazz to become one of the next great innovators of the music. Although, with Harrell being a diagnosed schizophrenic, he had a much different experience than many of his peers. This thesis intends on analyzing the life and improvisational style of Tom Harrell together with how it has developed over the course of his lengthy career. With Harrell’s career being vast and full of many collaborators, his musical voice evolved over the years from the late 1970s all the way to present day. In order to identify any changes, I will be taking three improvised solos from different years, analyzing the melodicism, harmonic style, and personal style of each solo. Each of the three solos are different in tempo and time feel to better get a sense of the more personal side of Harrell’s playing as well as getting a broader sense of the similarity and differences between the years. Finally, a comparison will be made between each solo, examining the evolution of Harrell’s improvisational voice
Learning About Resilience from Rural Interprofessional Healthcare Teams: Insights from the “First Wave” of COVID-19
No full textPublished version.Building resilience is a key concern for adult educators today as we face unprecedented global challenges such as the coronavirus disease-19 (COVID-19). Nowhere is this more apparent than in educational initiatives with health professionals who experience many stressors in their work, now amplified by the pandemic. This paper reports the results of focus groups with three interprofessional primary healthcare teams in rural Nova Scotia, Canada, in the fall of 2021. The aim was to learn about their lived experience during the first year of the pandemic, as a basis for considering how resilience could be nurtured and supported in rural team-based collaborative practices settings. Findings reveal that, while each collaborative team experienced recognized COVID-19 workplace stressors, they leveraged a store of collective resilience to navigate the pandemic. The trust, sense of purpose, and shared problem-solving skills they derived from working in collaborative structures over time enabled them to regain equilibrium and to adapt to new norms, and to transform thier practices. The study highlights the power of collaborative learning to strengthen overall ability for resilient performance, and the adaptive capacity that is required to deliver and sustain quality healthcare. The study highlights the need for continuing professional education that values naturally occurring practice-based learning. Adult educators are well positioned to support health professionals and health systems to nurture and support resilient action. They bring an understanding of effective collaborative tools and processes that foster dialogue and collective awareness that leads to a shared identity and understanding. As this study reveals, it is this shared identity and capacity arising within a group that enables them to draw on their collective sources of support to deal with adversity
