2020 Abstracts
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Sexual dimorphism and sexual selection in Alfaro cultratus and the effects of predation on these attributes
Bonnett, Kelsie; Golden, Kaitlyn; Johnson, Jerry (Brigham Young University)
Faculty Advisor: Johnson, Jerald (Brigham Young University, Biology)
Understanding life-history strategies allows us to know how a changing environment affects species and communities. Livebearing Poeciliid fish are commonly used as models to gain a better understanding of these strategies, but some species like Alfaro cultratus have been neglected in this process. A. cultratus is a freshwater fish with a unique keel-shaped anal fin commonly found along the eastern coast of Central America. To understand the life-history strategies of this species and use it as a future model, I am performing an experiment to: 1) determine if there is sexual selection in Alfaro cultratus considering both body size and anal fin length; 2) determine whether A. cultratus displays sexual selection; and 3) understand how predation influences both dimorphism and selection. To do this I will be performing a two-part experiment in which I will first analyze previously collected samples for morphological differences, and second perform a live experiment to test Alfaro female preference. By doing so I will be able to not only advance our understanding of A. cultratus, but of life-history theory and conservation strategies.
Faculty Advisor: Johnson, Jerald (Brigham Young University, Biology)
Understanding life-history strategies allows us to know how a changing environment affects species and communities. Livebearing Poeciliid fish are commonly used as models to gain a better understanding of these strategies, but some species like Alfaro cultratus have been neglected in this process. A. cultratus is a freshwater fish with a unique keel-shaped anal fin commonly found along the eastern coast of Central America. To understand the life-history strategies of this species and use it as a future model, I am performing an experiment to: 1) determine if there is sexual selection in Alfaro cultratus considering both body size and anal fin length; 2) determine whether A. cultratus displays sexual selection; and 3) understand how predation influences both dimorphism and selection. To do this I will be performing a two-part experiment in which I will first analyze previously collected samples for morphological differences, and second perform a live experiment to test Alfaro female preference. By doing so I will be able to not only advance our understanding of A. cultratus, but of life-history theory and conservation strategies.
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Smyd1 Histone Methyltransferase Activity in Heart Failure and Cardiac Hypertrophy Models
Szulik, Marta; Wang, Li; Franklin, Sarah. (University of Utah)
Faculty Advisor: Franklin, Sarah (Medicine, Internal Medicine)
Heart failure (HF) is a type of heart disease characterized by the structural and functional impairment of ventricular filling. In 2016, HF was the underlying cause of death in approximately 78,000 individuals and today more than 6.2 million Americans suffer from heart failure. HF is the final stage for many types of heart disease including cardiac hypertrophy. During hypertrophy, the ventricular walls thicken to help maintain the proper workload needed to continue supplying the body with oxygenated blood. In addition to increase in cell size, cardiac hypertrophy leads to cell death, fibrosis, metabolic reprogramming and reactivation of fetal gene expression. Gene expression is often modulated by changes in chromatin and histone structure via post-translational modifications (PTMs). Histone methylation, a covalent PTM, has been shown to play a significant role in cardiac development.
Smyd1 is a muscle specific lysine histone methyltransferase protein that has a role in early cardiac development and is known to methylate histone H3 on lysine-4. Additionally, loss of Smyd1 in adult mice models has been shown to induce heart failure and hypertrophy whereas overexpression of Smyd1 has been shown to restrict hypertrophic growth in cell model. Although Smyd1 knockdown experiments have been performed in vivo, the effects of knocking down Smyd1 in isolated cardiomyocytes has not been examined. Furthermore, the effects Smyd1 overexpression in adult mammalian heart failure is unknown.
This project seeks to characterize changes in global levels of histone PTM's as a result of either overexpressing or silencing Smyd1. Using proteomic analysis, we have identified the changes in histone methylation and consequently gene expression in the adult heart and isolated cells in response to Smyd1. Our results help us better understand Smyd1 role in the failing heart and help determine it therapeutic potential.
Faculty Advisor: Franklin, Sarah (Medicine, Internal Medicine)
Heart failure (HF) is a type of heart disease characterized by the structural and functional impairment of ventricular filling. In 2016, HF was the underlying cause of death in approximately 78,000 individuals and today more than 6.2 million Americans suffer from heart failure. HF is the final stage for many types of heart disease including cardiac hypertrophy. During hypertrophy, the ventricular walls thicken to help maintain the proper workload needed to continue supplying the body with oxygenated blood. In addition to increase in cell size, cardiac hypertrophy leads to cell death, fibrosis, metabolic reprogramming and reactivation of fetal gene expression. Gene expression is often modulated by changes in chromatin and histone structure via post-translational modifications (PTMs). Histone methylation, a covalent PTM, has been shown to play a significant role in cardiac development.
Smyd1 is a muscle specific lysine histone methyltransferase protein that has a role in early cardiac development and is known to methylate histone H3 on lysine-4. Additionally, loss of Smyd1 in adult mice models has been shown to induce heart failure and hypertrophy whereas overexpression of Smyd1 has been shown to restrict hypertrophic growth in cell model. Although Smyd1 knockdown experiments have been performed in vivo, the effects of knocking down Smyd1 in isolated cardiomyocytes has not been examined. Furthermore, the effects Smyd1 overexpression in adult mammalian heart failure is unknown.
This project seeks to characterize changes in global levels of histone PTM's as a result of either overexpressing or silencing Smyd1. Using proteomic analysis, we have identified the changes in histone methylation and consequently gene expression in the adult heart and isolated cells in response to Smyd1. Our results help us better understand Smyd1 role in the failing heart and help determine it therapeutic potential.
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Substrate specificity in variants of an aldehyde oxidoreductase
Carter, Riley; Hertig, Jess; Durrant, Doran (Southern Utah University)
Faculty Advisor: Pierce, Elizabeth (Science and Engineering, Physical Science)
Aldehyde oxidoreductases (AOR) are enzymes used to catalyze the conversion between aldehydes and carboxylic acids. Certain bacteria use these enzymes as a source of metabolism or to detoxify aldehydes to less toxic carboxylic acids: Desulfovibrio gigas uses a highly efficient enzyme (DgAOR) to oxidize benzaldehyde in metabolism while E. coli uses a periplasmic AOR (PaoABC) to detoxify aldehydes. These AORs are members of the xanthine oxidase family, but they don't metabolize many of the normal substrates characteristic of this enzyme family, namely purines. Moreover, the active sites of these enzymes have very different environments. Correia, et al (2014) characterized the kinetics and structure of DgAOR with several substrates and found that the Phe425 and Tyr535 residues at the active site likely stabilize aromatic aldehydes by pi stacking. This active site was also buried away from solvent. The active site of PaoABC lacked any significant aromatic residues and was positioned at the surface of the protein. The substrate stabilizing elements at this active site are Leu246 and Pro352. We are interested in why these active sites both are unreactive towards purines given their different chemical and location compared to the solvent. We propose that by mutating PaoABC to have smaller, nonpolar residues at the 246 and 352 position, we may be able to change the specificity of PaoABC to include purines. We also will mutate these residues to aromatic groups to probe at the chemical environment of the active site and its similarities to DgAOR.
Faculty Advisor: Pierce, Elizabeth (Science and Engineering, Physical Science)
Aldehyde oxidoreductases (AOR) are enzymes used to catalyze the conversion between aldehydes and carboxylic acids. Certain bacteria use these enzymes as a source of metabolism or to detoxify aldehydes to less toxic carboxylic acids: Desulfovibrio gigas uses a highly efficient enzyme (DgAOR) to oxidize benzaldehyde in metabolism while E. coli uses a periplasmic AOR (PaoABC) to detoxify aldehydes. These AORs are members of the xanthine oxidase family, but they don't metabolize many of the normal substrates characteristic of this enzyme family, namely purines. Moreover, the active sites of these enzymes have very different environments. Correia, et al (2014) characterized the kinetics and structure of DgAOR with several substrates and found that the Phe425 and Tyr535 residues at the active site likely stabilize aromatic aldehydes by pi stacking. This active site was also buried away from solvent. The active site of PaoABC lacked any significant aromatic residues and was positioned at the surface of the protein. The substrate stabilizing elements at this active site are Leu246 and Pro352. We are interested in why these active sites both are unreactive towards purines given their different chemical and location compared to the solvent. We propose that by mutating PaoABC to have smaller, nonpolar residues at the 246 and 352 position, we may be able to change the specificity of PaoABC to include purines. We also will mutate these residues to aromatic groups to probe at the chemical environment of the active site and its similarities to DgAOR.
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Small Mammal Communities of the Darhad Valley, Mongolia
Smith, Chyanne; Jal, Tumursukh; Duuji, Nyam-Ochir; Tumur, Battogtokh; Mull, John (Weber State University)
Faculty Advisor: Mull, John (Weber State University, College of Science; Zoology)
The Darhad Valley, Mongolia, is a sparsely populated area with abundant wildlife and numerous livestock, including: goats, yaks, horses, and sheep. Few studies completed in this location have placed an importance on obtaining baseline species data. To our knowledge, no data have been collected on small mammal diversity, density, and distribution. This study focused on live-trapping small mammals, with an emphasis on rodents, in six locations throughout the Darhad. We aimed to identify species currently present and develop protocols for future work. Captured rodents represented four families: Sciuridae, Arvicolinae, Cricetidae, and Muridae. Common species included striped dwarf hamsters (Cricetulus barabensis), Mongolian silver voles (Alticola semicanus), and Korean field mice (Apodemus peninsulae). Challenges encountered, which must be mitigated in future studies, include: curious humans, resource and waste management, grazing animals, and novel food sources. These studies should also emphasize community composition, range, and presence of ectoparasites, which could transfer zoonotic diseases.
Faculty Advisor: Mull, John (Weber State University, College of Science; Zoology)
The Darhad Valley, Mongolia, is a sparsely populated area with abundant wildlife and numerous livestock, including: goats, yaks, horses, and sheep. Few studies completed in this location have placed an importance on obtaining baseline species data. To our knowledge, no data have been collected on small mammal diversity, density, and distribution. This study focused on live-trapping small mammals, with an emphasis on rodents, in six locations throughout the Darhad. We aimed to identify species currently present and develop protocols for future work. Captured rodents represented four families: Sciuridae, Arvicolinae, Cricetidae, and Muridae. Common species included striped dwarf hamsters (Cricetulus barabensis), Mongolian silver voles (Alticola semicanus), and Korean field mice (Apodemus peninsulae). Challenges encountered, which must be mitigated in future studies, include: curious humans, resource and waste management, grazing animals, and novel food sources. These studies should also emphasize community composition, range, and presence of ectoparasites, which could transfer zoonotic diseases.
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Proteomic Analysis of Trichopteran Silk Fibre
Frandsen, Paul; Bursell, Madeline; Taylor, Adam; Wilson, Seth; Steeneck, Amy; Stewart, Russell (Brigham Young University)
Faculty Advisor: Frandsen, Paul (Life Sciences, Plant and Wildlife Sciences)
Caddisfly (Insecta: Trichoptera) silk is unique from other insect's silk in that it retains its adhesive capabilities, strength and viscoelasticity when submerged in water. To understand how caddisfly silk is capable of possessing these characteristics, it is essential to understand the protein foundation of the silk proteins. Caddisfly silk is complex and made up of different structures generated by processes that are unique to caddisfly silk. H-Fibroin and L-Fibroin have been identified as two of the major protein components within caddisfly silk (Hatano & Nagashima, 2015). The caddisfly silk fibre experiences unique structures not typically seen in nature. An understanding of the primary structure of the silk fibre is essential in understanding the complexity of the silk's capabilities. In this study, we used proteomic techniques to analyze the complex H-Fibroin protein and the silk fibre in order to look at the underlying structural features of the protein. In doing so, we identified post-translational phosphorylation, metal cation incorporation, and other structural features which contributes to Caddisfly silk's adhesive capabilities, strength and viscoelasticity when submerged in water.
Faculty Advisor: Frandsen, Paul (Life Sciences, Plant and Wildlife Sciences)
Caddisfly (Insecta: Trichoptera) silk is unique from other insect's silk in that it retains its adhesive capabilities, strength and viscoelasticity when submerged in water. To understand how caddisfly silk is capable of possessing these characteristics, it is essential to understand the protein foundation of the silk proteins. Caddisfly silk is complex and made up of different structures generated by processes that are unique to caddisfly silk. H-Fibroin and L-Fibroin have been identified as two of the major protein components within caddisfly silk (Hatano & Nagashima, 2015). The caddisfly silk fibre experiences unique structures not typically seen in nature. An understanding of the primary structure of the silk fibre is essential in understanding the complexity of the silk's capabilities. In this study, we used proteomic techniques to analyze the complex H-Fibroin protein and the silk fibre in order to look at the underlying structural features of the protein. In doing so, we identified post-translational phosphorylation, metal cation incorporation, and other structural features which contributes to Caddisfly silk's adhesive capabilities, strength and viscoelasticity when submerged in water.
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Prophylactic Treatment of Post-Traumatic Stress Disorder with Mifepristone and Propranolol
Boyce, Zach; Smith, Calvin; Martin, Ashlyn; Ketch, Yuko; Dugan, James; Wright, Cole (Brigham Young University)
Faculty Advisor: Jeffrey, Edwards (Brigham Young University, Physiology and Developmental Biology)
Post-traumatic stress disorder (PTSD) is a complex psychological disorder that affects about 1 of 4 individuals after a stressful/traumatic experience. One common model to induce PTSD in rats is social defeat (SD) combined with chronic light exposure. First, we screened rats for natural anxiety to use in the SD protocol. Next, elevated plus maze (EPM) and light-dark transition (LDT) tests were used to detect anxious behavior after SD. The SD protocol induced significant anxious behavior when compared to controls. Next, we performed long-term potentiation (LTP) field electrophysiology synaptic plasticity physiology experiments in brain slices of the ventral hippocampus (VH) and basolateral amygdala (BLA), regions known to have altered enhanced plasticity in PTSD. SD significantly increased LTP in the VH (~25% greater than control) and BLA (~35% greater than control). To determine whether a prophylactic treatment could prevent the physiological changes of PTSD, we simultaneously administered two drugs at 10 mg/kg doses by intraperitoneal injection one week prior to and for the duration of SD. The first, propranolol, is a beta-adrenergic receptor antagonist, and the second, mifepristone, is a glucocorticoid receptor antagonist; thus, treatment would target the action of stress hormones altered in PTSD. To determine whether a prophylactic treatment could prevent the physiological changes of PTSD, propranolol and mifepristone, antagonists of two stress receptors, were simultaneously administered at 10 mg/kg doses by intraperitoneal (IP) injection one week prior to and for the duration of SThese drugs significantly decreased LTP in the VH and BLA back to near-control levels while SD rats with vehicle injections still had elevated LTP. However, SD drug-treated rats did not show significant reductions in anxious behavior compared to non-injected SD rats and also exhibited significantly more anxious behavior than control rats, suggesting the IP injection induced added stress. Next, we used rtPCR to examine gene expression of drug targets and plasticity markers to determine potential mechanisms for observed LTP changes. In both the VH and BLA, SD was associated with a significant decrease in glucocorticoid and mineralocorticoid receptor expression, which was restored to control levels under drug treatment. Overall, our data suggest that propranolol and mifepristone together may be a potential prophylactic treatment for preventing PTSD through a mechanism likely mediated by glucocorticoid/mineralocorticoid receptors.
Faculty Advisor: Jeffrey, Edwards (Brigham Young University, Physiology and Developmental Biology)
Post-traumatic stress disorder (PTSD) is a complex psychological disorder that affects about 1 of 4 individuals after a stressful/traumatic experience. One common model to induce PTSD in rats is social defeat (SD) combined with chronic light exposure. First, we screened rats for natural anxiety to use in the SD protocol. Next, elevated plus maze (EPM) and light-dark transition (LDT) tests were used to detect anxious behavior after SD. The SD protocol induced significant anxious behavior when compared to controls. Next, we performed long-term potentiation (LTP) field electrophysiology synaptic plasticity physiology experiments in brain slices of the ventral hippocampus (VH) and basolateral amygdala (BLA), regions known to have altered enhanced plasticity in PTSD. SD significantly increased LTP in the VH (~25% greater than control) and BLA (~35% greater than control). To determine whether a prophylactic treatment could prevent the physiological changes of PTSD, we simultaneously administered two drugs at 10 mg/kg doses by intraperitoneal injection one week prior to and for the duration of SD. The first, propranolol, is a beta-adrenergic receptor antagonist, and the second, mifepristone, is a glucocorticoid receptor antagonist; thus, treatment would target the action of stress hormones altered in PTSD. To determine whether a prophylactic treatment could prevent the physiological changes of PTSD, propranolol and mifepristone, antagonists of two stress receptors, were simultaneously administered at 10 mg/kg doses by intraperitoneal (IP) injection one week prior to and for the duration of SThese drugs significantly decreased LTP in the VH and BLA back to near-control levels while SD rats with vehicle injections still had elevated LTP. However, SD drug-treated rats did not show significant reductions in anxious behavior compared to non-injected SD rats and also exhibited significantly more anxious behavior than control rats, suggesting the IP injection induced added stress. Next, we used rtPCR to examine gene expression of drug targets and plasticity markers to determine potential mechanisms for observed LTP changes. In both the VH and BLA, SD was associated with a significant decrease in glucocorticoid and mineralocorticoid receptor expression, which was restored to control levels under drug treatment. Overall, our data suggest that propranolol and mifepristone together may be a potential prophylactic treatment for preventing PTSD through a mechanism likely mediated by glucocorticoid/mineralocorticoid receptors.
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Positioning Nucleosomes with 601 DNA Sequence to Restore GFP Expression
Hales, Emily; Lundgren, Jane; Carter, John; Kempton, Colton; Johnson, Steven (Brigham Young University)
Faculty Advisor: Johnson, Steven (Brigham Young University, Molecular and Microbiology)
The mechanisms of transgene silencing in C. elegans are poorly understood, despite the importance of the nematode as a model for genetic research. Insertion of a transgene led to the expression of GFP in both the body wall and pharyngeal muscle cells of C. elegans as expected. However, subsequent generations stopped expressing body wall GFP. To reverse silencing, we have flanked the enhancers responsible for GFP expression with 601 sequences. The 601 sequence strongly positions nucleosomes. We hypothesize that this positioning will eliminate transgenerational gene silencing of body wall GFP.
Faculty Advisor: Johnson, Steven (Brigham Young University, Molecular and Microbiology)
The mechanisms of transgene silencing in C. elegans are poorly understood, despite the importance of the nematode as a model for genetic research. Insertion of a transgene led to the expression of GFP in both the body wall and pharyngeal muscle cells of C. elegans as expected. However, subsequent generations stopped expressing body wall GFP. To reverse silencing, we have flanked the enhancers responsible for GFP expression with 601 sequences. The 601 sequence strongly positions nucleosomes. We hypothesize that this positioning will eliminate transgenerational gene silencing of body wall GFP.
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Sex differences in MAP kinase activation in the periaqueductal gray after morphine treatment
Ashley McCarty, Akila Ram, Max V. McDermott, Erin N. Bobeck (Utah State University)
Faculty Advisor: Bobeck, Erin (College of Science, Biology Department)
Morphine is a potent opioid analgesic, but its long term use can lead to negative side effects, including tolerance, which is a decrease in the effectiveness of the opioid. An area of active interest is looking into the molecular effects of chronic morphine treatment in the Periaqueductal gray (PAG), a brain region that controls descending pain modulation. One such molecular target within the PAG is extracellular-signal regulated kinase 1/2 (ERK). Previous studies have shown that pharmacological inhibition of ERK enhanced morphine tolerance, indicating that ERK activity is associated with better responsiveness to morphine. The PAG is known to contain a heterogenous population of neurons including GABA and glutamate subtypes. However, which neurons ERK is activated in within the PAG following morphine tolerance is unknown. Further, there are known differences in PAG activity between male and female mice. However, these sex-differences have not been well studied after morphine tolerance using acute pain tests. The purpose of this research is to investigate differences in ERK activation following morphine tolerance in male and female mice. We treated wild-type male and female mice with morphine (10 mg/kg, i.p.) or saline for 5 days to induce morphine tolerance, following which both behavior and protein immunofluorescence were assessed. We observe sex-specific differences in ERK activation levels and morphine antinociceptive tolerance in mice. We also assessed co-localization of ERK with GABA and glutamate neurons after morphine tolerance. The study will help us understand the cell-type specificity of kinase activation following morphine tolerance. Further this will give us more information about the nature of neurons that are contributing to sex-differences in opioid functions within the PAG
Faculty Advisor: Bobeck, Erin (College of Science, Biology Department)
Morphine is a potent opioid analgesic, but its long term use can lead to negative side effects, including tolerance, which is a decrease in the effectiveness of the opioid. An area of active interest is looking into the molecular effects of chronic morphine treatment in the Periaqueductal gray (PAG), a brain region that controls descending pain modulation. One such molecular target within the PAG is extracellular-signal regulated kinase 1/2 (ERK). Previous studies have shown that pharmacological inhibition of ERK enhanced morphine tolerance, indicating that ERK activity is associated with better responsiveness to morphine. The PAG is known to contain a heterogenous population of neurons including GABA and glutamate subtypes. However, which neurons ERK is activated in within the PAG following morphine tolerance is unknown. Further, there are known differences in PAG activity between male and female mice. However, these sex-differences have not been well studied after morphine tolerance using acute pain tests. The purpose of this research is to investigate differences in ERK activation following morphine tolerance in male and female mice. We treated wild-type male and female mice with morphine (10 mg/kg, i.p.) or saline for 5 days to induce morphine tolerance, following which both behavior and protein immunofluorescence were assessed. We observe sex-specific differences in ERK activation levels and morphine antinociceptive tolerance in mice. We also assessed co-localization of ERK with GABA and glutamate neurons after morphine tolerance. The study will help us understand the cell-type specificity of kinase activation following morphine tolerance. Further this will give us more information about the nature of neurons that are contributing to sex-differences in opioid functions within the PAG
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Supplemental treatment options for diabetes: how DHE induces Nr4a1 expression and subsequent β-cell function
Brown, Nathan; Herring, Jacob; Tessem, Jeffery (Brigham Young University)
Faculty Advisor: Tessem, Jeffery (Brigham young University; Nutrition, Dietetics, and Food Science)
Diabetes is a global epidemic affecting millions of people. The total estimated cost of diabetes in the U.S. during 2017 was 327 billion dollars. Diabetes is characterized by the loss of pancreatic β-cell function which is caused by an autoimmune disorder in Type 1 diabetes or insulin resistance and β-cell exhaustion in Type 2 (T2D) diabetes.
It is shown that β-cell mitochondrial respiration is dependent on the nuclear receptor Nr4a1. Respiration rates of cells lacking Nr4a1 in the presence of 16 mM glucose resulted in a significant decrease in glucose-stimulated insulin secretion by impeding the production of ATP. It was also found that knockdown of Nr4a1 results in decreased expression of mitochondrial dehydrogenase subunits Idh3g and Sdhb. Thus, the orphan nuclear receptor Nr4a1 is critical for β-cell mitochondrial function and insulin secretion.
In subsequent studies it was shown that dihydroergotamine (DHE) induces Nr4a1 expression via recruitment of the super elongation complex to enable elongation of Nr4a1 promoter paused RNA polymerase II. While these experiments have been shown in cancer cells, I hypothesize that DHE will up-regulate Nr4a1 and other downstream targets. To test this I will use an in-vitro model to culture INS-1 832/3 rat insulinoma cell lines as a useful model for insulin secretion regulation and pancreatic islet beta-cell function studies. This study will shed further light on the regulation of the Nr4a1 nuclear receptor in pancreatic β-cells.
Faculty Advisor: Tessem, Jeffery (Brigham young University; Nutrition, Dietetics, and Food Science)
Diabetes is a global epidemic affecting millions of people. The total estimated cost of diabetes in the U.S. during 2017 was 327 billion dollars. Diabetes is characterized by the loss of pancreatic β-cell function which is caused by an autoimmune disorder in Type 1 diabetes or insulin resistance and β-cell exhaustion in Type 2 (T2D) diabetes.
It is shown that β-cell mitochondrial respiration is dependent on the nuclear receptor Nr4a1. Respiration rates of cells lacking Nr4a1 in the presence of 16 mM glucose resulted in a significant decrease in glucose-stimulated insulin secretion by impeding the production of ATP. It was also found that knockdown of Nr4a1 results in decreased expression of mitochondrial dehydrogenase subunits Idh3g and Sdhb. Thus, the orphan nuclear receptor Nr4a1 is critical for β-cell mitochondrial function and insulin secretion.
In subsequent studies it was shown that dihydroergotamine (DHE) induces Nr4a1 expression via recruitment of the super elongation complex to enable elongation of Nr4a1 promoter paused RNA polymerase II. While these experiments have been shown in cancer cells, I hypothesize that DHE will up-regulate Nr4a1 and other downstream targets. To test this I will use an in-vitro model to culture INS-1 832/3 rat insulinoma cell lines as a useful model for insulin secretion regulation and pancreatic islet beta-cell function studies. This study will shed further light on the regulation of the Nr4a1 nuclear receptor in pancreatic β-cells.
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Simulated Physiological Environment Stimulates Corrosion in Stainless Steel Substrates following Carbon-Infiltrated Carbon Nanotube Surface Modification
Bowden, Lucy; Monroe, Jacquelyn; Bowden, Anton E.; Jensen, Brian D. (Brigham Young University)
Faculty Advisor: Bowden, Anton (Engineering, Mechanical Engineering); Jensen, Brian (Engineering, Mechanical Engineering)
Previously our lab has shown that carbon-infiltrated carbon nanotube (CI-CNT) surfaces enhance osseointegration and resist biofilm formation, making them attractive possibilities as orthopedic implant materials. For these applications, CI-CNTs and their underlying substrate material must be able to withstand aqueous physiologic conditions. Due to microstructural changes that occur during CI-CNT production, we hypothesized that stainless steel substrate materials experience a loss of their protective, passivating layer, subsequently corroding when immersed in a simulated biological environment. The purpose of the study was to compare corrosion resistance of CI-CNT coated stainless steel substrates to bare stainless steel control samples after two days of incubation in different physiological analog media.
CI-CNTs were grown on 316L stainless steel samples which were sonicated for 20 minutes in isopropyl alcohol and given a 2 minute heat treatment in air at 800°C, followed by a 20 minute growth at the same temperature in ethylene and argon. Carbon infiltration was done for 5 minutes in the same gases at 900°C. The samples were autoclaved and placed into different media including deionized water, phosphor buffered saline solution (PBS), and DMEM culture media. The samples were then incubated for 48 hours at 37°C.
Macroscopic observation showed no obvious signs of corrosion (e.g., discoloration of the liquid media, cloudiness, physical changes in sample appearance) for any of the control samples, or for CI-CNT coated samples in deionized water. In contrast, the CI-CNT coated samples immersed in PBS and culture media exhibited significant discoloration and a cloudy appearance. Subsequent SEM images of the CI-CNT coated samples which had been immersed in culture media and PBS showed foreign residue. Energy dispersive x-ray analysis characterized this residue as having markedly higher levels of sodium and phosphorus than a baseline CI-CNT coated stainless steel sample. SEM images of the bare stainless steel samples and the CI-CNT samples cultured in deionized water showed no signs of corrosion or residue.
Our preliminary results illustrate that media containing salts initiated corrosion of CI-CNT coated stainless steel samples, likely due to disruption of the passivating layer in the substrate. Future work will explore methods for re-establishing the passivating layer in stainless steel materials.
Faculty Advisor: Bowden, Anton (Engineering, Mechanical Engineering); Jensen, Brian (Engineering, Mechanical Engineering)
Previously our lab has shown that carbon-infiltrated carbon nanotube (CI-CNT) surfaces enhance osseointegration and resist biofilm formation, making them attractive possibilities as orthopedic implant materials. For these applications, CI-CNTs and their underlying substrate material must be able to withstand aqueous physiologic conditions. Due to microstructural changes that occur during CI-CNT production, we hypothesized that stainless steel substrate materials experience a loss of their protective, passivating layer, subsequently corroding when immersed in a simulated biological environment. The purpose of the study was to compare corrosion resistance of CI-CNT coated stainless steel substrates to bare stainless steel control samples after two days of incubation in different physiological analog media.
CI-CNTs were grown on 316L stainless steel samples which were sonicated for 20 minutes in isopropyl alcohol and given a 2 minute heat treatment in air at 800°C, followed by a 20 minute growth at the same temperature in ethylene and argon. Carbon infiltration was done for 5 minutes in the same gases at 900°C. The samples were autoclaved and placed into different media including deionized water, phosphor buffered saline solution (PBS), and DMEM culture media. The samples were then incubated for 48 hours at 37°C.
Macroscopic observation showed no obvious signs of corrosion (e.g., discoloration of the liquid media, cloudiness, physical changes in sample appearance) for any of the control samples, or for CI-CNT coated samples in deionized water. In contrast, the CI-CNT coated samples immersed in PBS and culture media exhibited significant discoloration and a cloudy appearance. Subsequent SEM images of the CI-CNT coated samples which had been immersed in culture media and PBS showed foreign residue. Energy dispersive x-ray analysis characterized this residue as having markedly higher levels of sodium and phosphorus than a baseline CI-CNT coated stainless steel sample. SEM images of the bare stainless steel samples and the CI-CNT samples cultured in deionized water showed no signs of corrosion or residue.
Our preliminary results illustrate that media containing salts initiated corrosion of CI-CNT coated stainless steel samples, likely due to disruption of the passivating layer in the substrate. Future work will explore methods for re-establishing the passivating layer in stainless steel materials.
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Examining the Influence of Science-Infused Literacy Instruction on Reading Motivation and Quality of Informational Text
Judd, Emma J.; Clark, Sarah K. (Brigham Young University)
Faculty Advisor: Clark, Sarah (Education, Teacher Education)
The study examined the integration of science into literacy instruction for the early grades. The study specifically explored how science-infused literacy instruction influenced the quality of compare and contrast science informational text produced by second graders, compared to literacy instruction alone. Additionally, the motivation of the students to read was examined in connection to the quality of the informational text they produced. The participants were second-graders (N = 72) between the ages of 7 – 9 and were enrolled in the first quarter of the school year at a Title 1 school. Seventy-three percent of these students were White, 22% were Hispanic, 2% were Asian, and 1% were Black, with 63% of the students eligible for free or reduced lunch. The treatment group (N = 35) received science-infused literacy instruction and the control group (N = 37) received their regular literacy instruction. Two instruments for measurement were used: a motivation survey which measured the students’ motivation to read, and a weighted writing rubric with an emphasis on signal words, content-specific vocabulary words, and word count, which was used to score the informational text writing samples produced by the students. The students took the reading motivation survey and answered the same informational text writing prompt before and after the instruction. The instruction for compare and contrast writing took place over the course of a four-week unit, and consisted of three 30-minute lessons weekly. The research was designed as quasi-experimental using a paired samples t-test with follow-up effect size measures. The results demonstrate that students in the treatment group produced significantly higher reading motivation scores but wrote lower-quality text, while students in the control group produced lower motivation scores but wrote higher-quality informational text. Implications from this study will be provided for educators and literacy instructional practices, and for researchers and future studies.
Faculty Advisor: Clark, Sarah (Education, Teacher Education)
The study examined the integration of science into literacy instruction for the early grades. The study specifically explored how science-infused literacy instruction influenced the quality of compare and contrast science informational text produced by second graders, compared to literacy instruction alone. Additionally, the motivation of the students to read was examined in connection to the quality of the informational text they produced. The participants were second-graders (N = 72) between the ages of 7 – 9 and were enrolled in the first quarter of the school year at a Title 1 school. Seventy-three percent of these students were White, 22% were Hispanic, 2% were Asian, and 1% were Black, with 63% of the students eligible for free or reduced lunch. The treatment group (N = 35) received science-infused literacy instruction and the control group (N = 37) received their regular literacy instruction. Two instruments for measurement were used: a motivation survey which measured the students’ motivation to read, and a weighted writing rubric with an emphasis on signal words, content-specific vocabulary words, and word count, which was used to score the informational text writing samples produced by the students. The students took the reading motivation survey and answered the same informational text writing prompt before and after the instruction. The instruction for compare and contrast writing took place over the course of a four-week unit, and consisted of three 30-minute lessons weekly. The research was designed as quasi-experimental using a paired samples t-test with follow-up effect size measures. The results demonstrate that students in the treatment group produced significantly higher reading motivation scores but wrote lower-quality text, while students in the control group produced lower motivation scores but wrote higher-quality informational text. Implications from this study will be provided for educators and literacy instructional practices, and for researchers and future studies.
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Aggies Go Green: Sustainable Transportation
Kaytriauna Flint, Allison Fishler, Mosese Manu, and Justus Te'i (Utah State University)
Faculty Advisor: Soyer, Mehmet (College of Humanities and Social Sciences; Sociology, Social Work and Anthropology Department)
Here at Utah State, there are many resources available for students, staff, faculty, and administration to travel to and from campus in eco-friendly ways. While there are many resources readily available, they are not well known across campus. Our initiative is to bring awareness to these hard-working groups and generous programs while incentivizing those who participate in our social media campaign where they will submit creative photos of their sustainable transportation to and from campus. Not only will it be extremely beneficial for these groups and programs across campus to get well-deserved recognition through this initiative, but it will give Aggies the greater opportunity to Go Green and travel to and from campus in an eco-friendly way!
Faculty Advisor: Soyer, Mehmet (College of Humanities and Social Sciences; Sociology, Social Work and Anthropology Department)
Here at Utah State, there are many resources available for students, staff, faculty, and administration to travel to and from campus in eco-friendly ways. While there are many resources readily available, they are not well known across campus. Our initiative is to bring awareness to these hard-working groups and generous programs while incentivizing those who participate in our social media campaign where they will submit creative photos of their sustainable transportation to and from campus. Not only will it be extremely beneficial for these groups and programs across campus to get well-deserved recognition through this initiative, but it will give Aggies the greater opportunity to Go Green and travel to and from campus in an eco-friendly way!
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Coding and Mathematics Skills: Case Studies
Evans, Hannah; Peterson, Rebecca (Utah State University)
Faculty Advisor: Shumway, Jessica (Emma Eccles Jones College of Education & Human Services, School of Teacher Education and Leadership); Clarke-Midura, Jody (Emma Eccles Jones College of Education & Human Services, Instructional Teachnology and Learning Sciences Department); Lee, Victor (Emma Eccles Jones College of Education & Human Services, Instruction Technology and Learning Sciences Department); Silvis, Deborah (Emma Eccles Jones College of Education & Human Services, Instruction Technology and Learning Sciences Department)
The push for computer science integration in kindergarten classrooms is a surfacing topic in public education in the United States. One approach to this is to integrate computer science with mathematics. However, there is minimal research on computer science and computational thinking as it relates to mathematics in early childhood education. In order to address this need, we are part of a larger research project that is studying the integration of computer science and mathematics in kindergarten classrooms. Specifically, we are exploring computational thinking (CT) elements that we see students engaging in (e.g., algorithmic thinking, debugging, and decomposition) while at the same time exploring mathematics skills that emerge (e.g., measurement, spatial reasoning, and pattern recognition). We study these skills and elements as we teach formal coding instruction using play-based, screen free coding robots. In this presentation, we will present early results of this integration in local kindergarten classrooms. Our main research question is: What CT and mathematics skills and strategies emerge as a result of this formal coding instruction?
Our sample consists of 16 kindergarten students. Groups of 3-4 students participated in six 30-minute coding lessons, followed by an assessment interview. Our data set is made up of video data from both the coding instruction and the assessment interviews, as well as field notes and assessment score sheets. We will present descriptive statistics regarding these assessments, as well as in-depth case studies of 2 students (one student who scored high on their post-test, and one who scored low). We will present data from the videos of their individual experiences as they engaged in formal instruction, as well as data regarding their assessments, in order to answer our research question and analyze what CT and mathematics skills and strategies emerged as a result of their formal coding instruction.
Faculty Advisor: Shumway, Jessica (Emma Eccles Jones College of Education & Human Services, School of Teacher Education and Leadership); Clarke-Midura, Jody (Emma Eccles Jones College of Education & Human Services, Instructional Teachnology and Learning Sciences Department); Lee, Victor (Emma Eccles Jones College of Education & Human Services, Instruction Technology and Learning Sciences Department); Silvis, Deborah (Emma Eccles Jones College of Education & Human Services, Instruction Technology and Learning Sciences Department)
The push for computer science integration in kindergarten classrooms is a surfacing topic in public education in the United States. One approach to this is to integrate computer science with mathematics. However, there is minimal research on computer science and computational thinking as it relates to mathematics in early childhood education. In order to address this need, we are part of a larger research project that is studying the integration of computer science and mathematics in kindergarten classrooms. Specifically, we are exploring computational thinking (CT) elements that we see students engaging in (e.g., algorithmic thinking, debugging, and decomposition) while at the same time exploring mathematics skills that emerge (e.g., measurement, spatial reasoning, and pattern recognition). We study these skills and elements as we teach formal coding instruction using play-based, screen free coding robots. In this presentation, we will present early results of this integration in local kindergarten classrooms. Our main research question is: What CT and mathematics skills and strategies emerge as a result of this formal coding instruction?
Our sample consists of 16 kindergarten students. Groups of 3-4 students participated in six 30-minute coding lessons, followed by an assessment interview. Our data set is made up of video data from both the coding instruction and the assessment interviews, as well as field notes and assessment score sheets. We will present descriptive statistics regarding these assessments, as well as in-depth case studies of 2 students (one student who scored high on their post-test, and one who scored low). We will present data from the videos of their individual experiences as they engaged in formal instruction, as well as data regarding their assessments, in order to answer our research question and analyze what CT and mathematics skills and strategies emerged as a result of their formal coding instruction.
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Optogenetics in Engineered Cardiac Tissue Maturation
Moncada, Silvia; Allen, Bryce; Hafen, Tanner; Valencia-Amores, Sebastian; Hanson, Luke; Dorian, Sariah; Bechtel, Matth;ew; Smith, Seth; Myres, Isaac; Holding, Clayton; Jacobs, Dallin; Hellwig, Lexi; White, Joshua; Evanson, Davin; Cheney, Cladin; Taylor, Sloan; Grossman, Jesse; Donaldson, Jesse; Jepsen, Emily; Johnston, Maren; Porter, Kaiden; Jardine, Alyson; Garfield, Seth; Larson, Spencer; Gardiner (Brigham Young University)
Faculty Advisor: Mizrachi, Dario (College of Life Sciences, Physiology & Molecular Biology)
Heart disease is the leading cause of death in the United States. During myocardial infarction cardiac tissue suffers a lack of nutrients and oxygen that leads to the formation of unregenerable scar tissue which causes a loss of myocardial functionality. With the advent of human induced pluripotent stem cells (hiPSC), the promise of engineering autologous cardiac tissues (ECTs) as a translatable treatment to cardiac disease and as a model for pharmaceutical research is ever closer. We create ECTs using iPS-human induced cardiomyocytes (hiCMs) and extra cellular matrix (ECM) derived from a decellularized left ventricle of a porcine heart. Decellularized matrices allow the preservation of important architectural cues found in the native heart for hiCMs development (Momtahan, 2015). Nevertheless, ECTs still face some challenges before they can be useful in a clinical or pharmaceutical research setting i.e. poor ECT contractile force, hiCM maturity, proper cell morphology and architecture, etc. (Dwenger, 2018). In this study, we seek to combine the mechanical cues of the preserved architecture of a decellularized matrix with the spatiotemporal accuracy of optogenetics as a novel technique to stimulate ECT functionality assessed through contractile force, proper hiCM elongation, and alignment.
Faculty Advisor: Mizrachi, Dario (College of Life Sciences, Physiology & Molecular Biology)
Heart disease is the leading cause of death in the United States. During myocardial infarction cardiac tissue suffers a lack of nutrients and oxygen that leads to the formation of unregenerable scar tissue which causes a loss of myocardial functionality. With the advent of human induced pluripotent stem cells (hiPSC), the promise of engineering autologous cardiac tissues (ECTs) as a translatable treatment to cardiac disease and as a model for pharmaceutical research is ever closer. We create ECTs using iPS-human induced cardiomyocytes (hiCMs) and extra cellular matrix (ECM) derived from a decellularized left ventricle of a porcine heart. Decellularized matrices allow the preservation of important architectural cues found in the native heart for hiCMs development (Momtahan, 2015). Nevertheless, ECTs still face some challenges before they can be useful in a clinical or pharmaceutical research setting i.e. poor ECT contractile force, hiCM maturity, proper cell morphology and architecture, etc. (Dwenger, 2018). In this study, we seek to combine the mechanical cues of the preserved architecture of a decellularized matrix with the spatiotemporal accuracy of optogenetics as a novel technique to stimulate ECT functionality assessed through contractile force, proper hiCM elongation, and alignment.
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UAV Photogrammetry Ground Truth Spacing Methodology to Accurately Model Reservoir Shorelines
(Pace, Jenessa; Ence, Elodie; Kunz, Allison; Stevens, Rebecca; Kunz, Amber; Cooper, Izaak; Nelson, Alicia; Asplund, Alyssa; Stock, Julianna) (Brigham Young University)
Faculty Advisor: Williams, Gustavious (Ira A. Fulton College of Engineering and Technology, Civil and Environmental Engineering)
Photogrammetry using Unmanned Aerial Vehicles (UAV) has become more relevant to water resources issues. The models generated can be highly accurate and detailed. The use of ground truth is an integral part of ensuring the accuracy of such models. Ground truth based on GPS-obtained data of visual targets gathered in the field prior to UAV data collection are used to improve post processing accuracy. Proper spacing of ground truth is primarily dependent on the flight path of the UAV during data collection, flight height, and image resolution.
One developing task is creating models of full-pool bathymetric maps for reservoirs - using UAVs for above the waterline and sonar for below. Due to their erratic shapes, capturing the shorelines of reservoirs requires erratic flight paths. Planning ground truth spacing requires special care.
To determine proper ground truth spacing we completed a field survey at Starvation Reservoir, near Duchesne, Utah. We selected a two mile stretch along the north side of the reservoir to test various ground truth spacings. We flew the test stretch with two flights, one taking nadir photos and one with the photos taken at an angle of about 30 degrees, more normal to the shoreline. The primary placement of ground truth points was approximately 0.25 miles apart. After the data was recorded, we created models using Metashape software using different ground truth spacing, using spacings of 0.25, 0.5 and 1 mile. We used Cloud Compare software to determine the error between each model. We assumed that the model generated using 0.25 points/mile was "truth". We used this preliminary information to determine that for bathymetry maps, a ground truth spacing of 1 mile/point was acceptable, we are continuing our research to refine this finding.
Faculty Advisor: Williams, Gustavious (Ira A. Fulton College of Engineering and Technology, Civil and Environmental Engineering)
Photogrammetry using Unmanned Aerial Vehicles (UAV) has become more relevant to water resources issues. The models generated can be highly accurate and detailed. The use of ground truth is an integral part of ensuring the accuracy of such models. Ground truth based on GPS-obtained data of visual targets gathered in the field prior to UAV data collection are used to improve post processing accuracy. Proper spacing of ground truth is primarily dependent on the flight path of the UAV during data collection, flight height, and image resolution.
One developing task is creating models of full-pool bathymetric maps for reservoirs - using UAVs for above the waterline and sonar for below. Due to their erratic shapes, capturing the shorelines of reservoirs requires erratic flight paths. Planning ground truth spacing requires special care.
To determine proper ground truth spacing we completed a field survey at Starvation Reservoir, near Duchesne, Utah. We selected a two mile stretch along the north side of the reservoir to test various ground truth spacings. We flew the test stretch with two flights, one taking nadir photos and one with the photos taken at an angle of about 30 degrees, more normal to the shoreline. The primary placement of ground truth points was approximately 0.25 miles apart. After the data was recorded, we created models using Metashape software using different ground truth spacing, using spacings of 0.25, 0.5 and 1 mile. We used Cloud Compare software to determine the error between each model. We assumed that the model generated using 0.25 points/mile was "truth". We used this preliminary information to determine that for bathymetry maps, a ground truth spacing of 1 mile/point was acceptable, we are continuing our research to refine this finding.
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Validating Ductility Scaling Relationships Using DIC
Buxton, Ashley; Ahmed, Jasmin; Smith, Adam; Rowley, Robert; Kingstedt, Owen; Berke, Ryan (Utah State University)
Faculty Advisor: Berke, Ryan (College of Engineering, Menanical and Aerospace Engineering Department)
As nuclear facilities grow older, the Department of Energy (DOE) seeks to understand how materials degrade under irradiation conditions. However, engineering-scale radioactive specimens are expensive to irradiate and difficult to handle. Thus, there is significant interest in new methods to characterize materials using miniaturized specimens. In recent years, several promising techniques have gained popularity (for example: nano-indentation, MEMs-based micro-tension, or nano-pillar compression), but there remains a significant gap in translating measurements at a micro- or nano-scale to material properties at an engineering scale.
In the late stages of ductility testing, localized necking means that two specimens of the same material but differing dimensions can produce drastically different elongation measurements. Barba's Law addresses this through scaling relationships. The law's key assumption is that similarly sized tensile specimens develop geometrically similar necked regions. The presented work utilizes this relationship to bridge ductility tests across length scales.
Throughout this research, full-field displacements are measured using Digital Image Correlation (DIC). In brief, DIC works by recording images of a specimen before and after deformation with a digital camera, then comparing the images to compute deformation. The gauge region is then varied to assess whether Barba's Law can be satisfied with a single long specimen and multiple shorter gauge regions. Multiple physical specimen lengths are then measured to validate the DIC results.
Faculty Advisor: Berke, Ryan (College of Engineering, Menanical and Aerospace Engineering Department)
As nuclear facilities grow older, the Department of Energy (DOE) seeks to understand how materials degrade under irradiation conditions. However, engineering-scale radioactive specimens are expensive to irradiate and difficult to handle. Thus, there is significant interest in new methods to characterize materials using miniaturized specimens. In recent years, several promising techniques have gained popularity (for example: nano-indentation, MEMs-based micro-tension, or nano-pillar compression), but there remains a significant gap in translating measurements at a micro- or nano-scale to material properties at an engineering scale.
In the late stages of ductility testing, localized necking means that two specimens of the same material but differing dimensions can produce drastically different elongation measurements. Barba's Law addresses this through scaling relationships. The law's key assumption is that similarly sized tensile specimens develop geometrically similar necked regions. The presented work utilizes this relationship to bridge ductility tests across length scales.
Throughout this research, full-field displacements are measured using Digital Image Correlation (DIC). In brief, DIC works by recording images of a specimen before and after deformation with a digital camera, then comparing the images to compute deformation. The gauge region is then varied to assess whether Barba's Law can be satisfied with a single long specimen and multiple shorter gauge regions. Multiple physical specimen lengths are then measured to validate the DIC results.
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Pluronic Micelles Shield Antiviral Cargo from Oxidation
Kjar, Andrew; Heap, Mitchell; Wadsworth, Ian; Vargis, Elizabeth; Britt, David (Utah State University)
Faculty Advisor: Britt, David (College of Engineering, Biological Engineering Department); Vargis, Elizabeth (College of Engineering, Biological Engineering Department)
Quercetin is a flavonoid that exhibits antiviral activity against cytomegalovirus infection, the leading cause of non-genetic sensorineural hearing loss in infants. However, delivering quercetin as an antiviral treatment is challenging as it is sparingly soluble in water and highly susceptible to oxidation once solubilized. This study investigated quercetin encapsulation in micelles formed from self-assembled nanocariiers of differing hydrophobic and hydrophilic chain lengths (specifically, F127, P123, and F68). Samples were investigated weekly for two months using UV-vis spectroscopy and dynamic light scattering to determine quercetin chemical stability and micelle size, respectively. Free quercetin and F68-encapsulated quercetin oxidized within one week in PBS, while quercetin encapsulated by Pluronics F127 and P123 remained stable and encapsulated over two months. Pluronics F127 and F68 have similar PEO chain lengths, but the lower hydrophobic PPO content of F68 was insufficient to allow quercetin-loaded F68 to form stable carriers. As a consequence, F68 also did not protect quercetin against oxidation. The decreased PEO chain length of P123 did not inhibit micelle formation nor oxidative protection. These data suggest the length of the hydrophilic chain is not a determining factor in the chemical stability of encapsulated quercetin. Instead, shielding effects appear to correlate to longer hydrophobic segment lengths, as in F127 and P123.
Conclusions: The ability of the selected Pluronics to encapsulate quercetin in stable micelles and inhibit oxidation was highly dependent on PEO/PPO ratios. This work indicates selection of the appropriate delivery vehicle is necessary to improve quercetin's efficacy as an antiviral and antioxidant for inhibiting CMV and associated SNHL.
Faculty Advisor: Britt, David (College of Engineering, Biological Engineering Department); Vargis, Elizabeth (College of Engineering, Biological Engineering Department)
Quercetin is a flavonoid that exhibits antiviral activity against cytomegalovirus infection, the leading cause of non-genetic sensorineural hearing loss in infants. However, delivering quercetin as an antiviral treatment is challenging as it is sparingly soluble in water and highly susceptible to oxidation once solubilized. This study investigated quercetin encapsulation in micelles formed from self-assembled nanocariiers of differing hydrophobic and hydrophilic chain lengths (specifically, F127, P123, and F68). Samples were investigated weekly for two months using UV-vis spectroscopy and dynamic light scattering to determine quercetin chemical stability and micelle size, respectively. Free quercetin and F68-encapsulated quercetin oxidized within one week in PBS, while quercetin encapsulated by Pluronics F127 and P123 remained stable and encapsulated over two months. Pluronics F127 and F68 have similar PEO chain lengths, but the lower hydrophobic PPO content of F68 was insufficient to allow quercetin-loaded F68 to form stable carriers. As a consequence, F68 also did not protect quercetin against oxidation. The decreased PEO chain length of P123 did not inhibit micelle formation nor oxidative protection. These data suggest the length of the hydrophilic chain is not a determining factor in the chemical stability of encapsulated quercetin. Instead, shielding effects appear to correlate to longer hydrophobic segment lengths, as in F127 and P123.
Conclusions: The ability of the selected Pluronics to encapsulate quercetin in stable micelles and inhibit oxidation was highly dependent on PEO/PPO ratios. This work indicates selection of the appropriate delivery vehicle is necessary to improve quercetin's efficacy as an antiviral and antioxidant for inhibiting CMV and associated SNHL.
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Scientific Research Accessibility in an Open Access World
Tucker, Ryan W.; Bundy, Bradley C. (Brigham Young University)
Faculty Advisor: Bundy, Bradley (Engineering, Chemical Engineering)
Peer-reviewed journal articles publications and their citation rate is the primary measure of research productivity and impact. Many measure of this impact have been developed and this has motivated many researchers to advertise and market their work. However, there are challenges with this system in that much of the scientific literature is not openly available and there are often high fees associated with making an article open access. Here I discuss this challenge and how engineering researchers are working to better make their research more available to the community.
Faculty Advisor: Bundy, Bradley (Engineering, Chemical Engineering)
Peer-reviewed journal articles publications and their citation rate is the primary measure of research productivity and impact. Many measure of this impact have been developed and this has motivated many researchers to advertise and market their work. However, there are challenges with this system in that much of the scientific literature is not openly available and there are often high fees associated with making an article open access. Here I discuss this challenge and how engineering researchers are working to better make their research more available to the community.
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