Matching Items (176)
Description
A previous study demonstrated that learning to lift an object is context-based and that in the presence of both the memory and visual cues, the acquired sensorimotor memory to manipulate an object in one context interferes with the performance of the same task in presence of visual information about a different context (Fu et al, 2012).
The purpose of this study is to know whether the primary motor cortex (M1) plays a role in the sensorimotor memory. It was hypothesized that temporary disruption of the M1 following the learning to minimize a tilt using a ‘L’ shaped object would negatively affect the retention of sensorimotor memory and thus reduce interference between the memory acquired in one context and the visual cues to perform the same task in a different context.
Significant findings were shown in blocks 1, 2, and 4. In block 3, subjects displayed insignificant amount of learning. However, it cannot be concluded that there is full interference in block 3. Therefore, looked into 3 effects in statistical analysis: the main effects of the blocks, the main effects of the trials, and the effects of the blocks and trials combined. From the block effects, there is a p-value of 0.001, and from the trial effects, the p-value is less than 0.001. Both of these effects indicate that there is learning occurring. However, when looking at the blocks * trials effects, we see a p-value of 0.002 < 0.05 indicating significant interaction between sensorimotor memories. Based on the results that were found, there is a presence of interference in all the blocks but not enough to justify the use of TMS in order to reduce interference because there is a partial reduction of interference from the control experiment. It is evident that the time delay might be the issue between context switches. By reducing the time delay between block 2 and 3 from 10 minutes to 5 minutes, I will hope to see significant learning to occur from the first trial to the second trial.
The purpose of this study is to know whether the primary motor cortex (M1) plays a role in the sensorimotor memory. It was hypothesized that temporary disruption of the M1 following the learning to minimize a tilt using a ‘L’ shaped object would negatively affect the retention of sensorimotor memory and thus reduce interference between the memory acquired in one context and the visual cues to perform the same task in a different context.
Significant findings were shown in blocks 1, 2, and 4. In block 3, subjects displayed insignificant amount of learning. However, it cannot be concluded that there is full interference in block 3. Therefore, looked into 3 effects in statistical analysis: the main effects of the blocks, the main effects of the trials, and the effects of the blocks and trials combined. From the block effects, there is a p-value of 0.001, and from the trial effects, the p-value is less than 0.001. Both of these effects indicate that there is learning occurring. However, when looking at the blocks * trials effects, we see a p-value of 0.002 < 0.05 indicating significant interaction between sensorimotor memories. Based on the results that were found, there is a presence of interference in all the blocks but not enough to justify the use of TMS in order to reduce interference because there is a partial reduction of interference from the control experiment. It is evident that the time delay might be the issue between context switches. By reducing the time delay between block 2 and 3 from 10 minutes to 5 minutes, I will hope to see significant learning to occur from the first trial to the second trial.
ContributorsHasan, Salman Bashir (Author) / Santello, Marco (Thesis director) / Kleim, Jeffrey (Committee member) / Helms Tillery, Stephen (Committee member) / Barrett, The Honors College (Contributor) / W. P. Carey School of Business (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Electromyography (EMG) and Electroencephalography (EEG) are techniques used to detect electrical activity produced by the human body. EMG detects electrical activity in the skeletal muscles, while EEG detects electrical activity from the scalp. The purpose of this study is to capture different types of EMG and EEG signals and to determine if the signals can be distinguished between each other and processed into output signals to trigger events in prosthetics. Results from the study suggest that the PSD estimates can be used to compare signals that have significant differences such as the wrist, scalp, and fingers, but it cannot fully distinguish between signals that are closely related, such as two different fingers. The signals that were identified were able to be translated into the physical output simulated on the Arduino circuit.
ContributorsJanis, William Edward (Author) / LaBelle, Jeffrey (Thesis director) / Santello, Marco (Committee member) / Barrett, The Honors College (Contributor) / Computer Science and Engineering Program (Contributor)
Created2013-12
Description
Dental caries also known as tooth decay is a bacterial infection that causes demineralization and destruction of enamel dentin and cementum in the tooth. This bacterium, Streprococcus mutans, feeds on the carbohydrates in the mouth and produces lactic acids that result in dental caries. This thesis discusses the use of plants to produce antibodies, Guy 13 and anti-GTFB to treat this dental disease. We believe these plant-derived antibodies will be effective to treat dental caries and economical to produce.
ContributorsSayegh, Luvenia Crystal (Author) / Chen, Qiang (Thesis director) / Garg, Vikas (Committee member) / Barrett, The Honors College (Contributor) / School of Letters and Sciences (Contributor)
Created2014-12
Description
Ebola hemorrhagic fever (EHF) is a severe and often fatal disease in human and nonhuman primates, caused by the Ebola virus. Approximately 30 years after the first epidemic, there is no vaccine or therapeutic medication approved to counter the Ebola virus. In this dissertation, a geminiviral replicon system was used to produce Ebola immune complex (EIC) in plant leaves and tested it as an Ebola vaccine. The EIC was produced in Nicotiana benthamiana leaves by fusing Ebola virus glycoprotein (GP1) to the C-terminus of heavy chain of 6D8 monoclonal antibody (mAb), which is specific to the 6D8 epitope of GP1, and co-expressing the fusion with the light chain of 6D8 mAb. EIC was purified by ammonium sulfate precipitation and protein A or protein G affinity chromatography. EIC was shown to be immunogenic in mice, but the level of antibody against Ebola virus was not sufficient to protect the mice from lethal the Ebola challenge. Hence, different adjuvants were tested in order to improve the immunogenicity of the EIC. Among several adjuvants that we used, Poly(I:C), which is a synthetic analog of double-stranded ribonucleic acid that can interact with a Toll-like receptor 3, strongly increased the efficacy of our Ebola vaccine. The mice immunized with EIC co-administered with Poly(I:C) produced high levels of neutralizing anti-Ebola IgG, and 80% of the mice were protected from the lethal Ebola virus challenge. Moreover, the EIC induced a predominant T-helper type 1 (Th1) response, whereas Poly(I:C) co-delivered with the EIC stimulated a mixed Th1/Th2 response. This result suggests that the protection against lethal Ebola challenge requires both Th1 and Th2 responses. In conclusion, this study demonstrated that the plant-produced EIC co-delivered with Poly(I:C) induced strong and protective immune responses to the Ebola virus in mice. These results support plant-produced EIC as a good vaccine candidate against the Ebola virus. It should be pursued further in primate studies, and eventually in clinical trials.
ContributorsPhoolcharoen, Waranyoo (Author) / Mason, Hugh S (Thesis advisor) / Chen, Qiang (Thesis advisor) / Arntzen, Charles J. (Committee member) / Change, Yung (Committee member) / Ma, Julian (Committee member) / Arizona State University (Publisher)
Created2010
Description
Coronavirus disease 2019 (COVID-19), an illness caused by severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2), has been responsible for significant social and economic
disruption, prompting an urgent search for therapeutic solutions. The spike protein of the virus
has been examined as an immunogenic target because of its role in viral binding and fusion
necessary for infection of host cells. Previous studies have identified a recombinant protein
(denoted as S1) that has been shown to potentially induce a neutralizing antibody response by
mimicking the structure of the SARS-CoV-2 spike protein. We have produced the S1 in plants
using agroinfiltration, a plant transformation technique whereby plasmid-containing
Agrobacterium tumefaciens is injected into Nicotiana benthamiana plants, resulting in transfer of
the desired gene from bacteria to plant cells. S1 was expressed to high levels within 5 days of
infiltration, and Western blot analysis showed recognition of the S1 by an anti-S1 antibody.
ELISA results exhibited increased binding activity to anti-S1 with increasing concentrations of
S1, indicating their specific interaction. This ongoing study will demonstrate the potential of a
plant-produced S1 as a vaccine, therapeutic, and diagnostic tool against COVID-19 that is not
only effective, but also cost-efficient and scalable in comparison to conventional mammalian cell
culture production methods.
coronavirus 2 (SARS-CoV-2), has been responsible for significant social and economic
disruption, prompting an urgent search for therapeutic solutions. The spike protein of the virus
has been examined as an immunogenic target because of its role in viral binding and fusion
necessary for infection of host cells. Previous studies have identified a recombinant protein
(denoted as S1) that has been shown to potentially induce a neutralizing antibody response by
mimicking the structure of the SARS-CoV-2 spike protein. We have produced the S1 in plants
using agroinfiltration, a plant transformation technique whereby plasmid-containing
Agrobacterium tumefaciens is injected into Nicotiana benthamiana plants, resulting in transfer of
the desired gene from bacteria to plant cells. S1 was expressed to high levels within 5 days of
infiltration, and Western blot analysis showed recognition of the S1 by an anti-S1 antibody.
ELISA results exhibited increased binding activity to anti-S1 with increasing concentrations of
S1, indicating their specific interaction. This ongoing study will demonstrate the potential of a
plant-produced S1 as a vaccine, therapeutic, and diagnostic tool against COVID-19 that is not
only effective, but also cost-efficient and scalable in comparison to conventional mammalian cell
culture production methods.
ContributorsNguyen, Katherine (Author) / Chen, Qiang (Thesis director) / Ghirlanda, Giovanna (Committee member) / Jugler, Collin (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
Tactile and proprioceptive sensory feedback are the two sensory modalities that make up haptic sensation. The degree which these two sensory modalities are integrated together is not very well known. To investigate this issue a set of experiments were set into motion separating these sensory modalities and testing what happens when a person’s proprioceptive system is perturbed. A virtual reality system with haptic feedback along with a weighted object were utilized in a reach, grasp, and lift task. The subjects would lift two objects sequentially and try to judge which one was heavier. This project was split into three different experiments to measure the subject’s perception in different situations. The first experiment utilized the virtual reality system to measure the perception when the subject only has proprioceptive inputs. The second experiment would include the virtual reality system and the weighted object to act as a comparison to the first experiment with the additional tactile input. The third experiment would then add perturbations to the proprioceptive inputs through the virtual reality system to investigate how perception will change. Results from experiment 1 and 2 showed that subjects are almost just as accurate with weight discrimination even if they only have proprioceptive inputs however, subjects are much more consistent in their weight discrimination with both sensory modalities. Results from experiment 3 showed that subjective perception does change when the proprioception is perturbed but the magnitude of that change in perception depends on the perturbation performed.
ContributorsPerrine, Jacob (Author) / Santello, Marco (Thesis director) / Toma, Simone (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
Honey bee workers display remarkable flexibility in the aging process. This plasticity is closely tied to behavioral maturation. Workers who initiate foraging behavior at earlier ages have shorter lifespans, and much of the variation in total lifespan can be explained by differences in pre-foraging lifespan. Vitellogenin (Vg), a yolk precursor protein, influences worker lifespan both as a regulator of behavioral maturation and through anti-oxidant and immune functions. Experimental reduction of Vg mRNA, and thus Vg protein levels, in wild-type bees results in precocious foraging behavior, decreased lifespan, and increased susceptibility to oxidative damage. We sought to separate the effects of Vg on lifespan due to behavioral maturation from those due to immune and antioxidant function using two selected strains of honey bees that differ in their phenotypic responsiveness to Vg gene knockdown. Surprisingly, we found that lifespans lengthen in the strain described as behaviorally and hormonally insensitive to Vg reduction. We then performed targeted gene expression analyses on genes hypothesized to mediate aging and lifespan: the insulin-like peptides (Ilp1 and 2) and manganese superoxide dismutase (mnSOD). The two honey bee Ilps are the most upstream components in the insulin-signaling pathway, which influences lifespan in Drosophila melanogaster and other organisms, while manganese superoxide dismutase encodes an enzyme with antioxidant functions in animals. We found expression differences in the llps in fat body related to behavior (llp1 and 2) and genetic background (Ilp2), but did not find strain by treatment effects. Expression of mnSOD was also affected by behavior and genetic background. Additionally, we observed a differential response to Vg knockdown in fat body expression of mnSOD, suggesting that antioxidant pathways may partially explain the strain-specific lifespan responses to Vg knockdown.
ContributorsIhle, Kate (Author) / Fondrk, M. Kim (Author) / Page, Robert (Author) / Amdam, Gro (Author) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor)
Created2015-01-01
Description
Plant viral vectors have previously been used to produce high expression levels of antibodies and other proteins of interest. By utilizing a transformed Agrobacterium with the vector containing the protein of interest for infiltration, viral vectors can easily reach the plant cells making it an effective form of transient protein expression. For this project two different plant viral vectors were compared; the geminiviral vector derived from Bean yellow dwarf virus (BeYDV) and the MagnICON vector system derived from Tobacco Mosaic Virus(TMV) and Potato Virus X(PVX). E16, an antibody against West Nile virus, has previously been expressed using both systems but expression levels between the systems were not directly compared. Agrobacterium tumefaciens EHA105 cells were transformed with both systems and expression levels of E16 were quantified using ELISAs. Results showed very low expression levels of E16 using the geminiviral vector indicating a need for further investigation into the clone used as previous studies reported much higher expression levels with the system.
ContributorsMurphy, Skylar (Author) / Chen, Qiang (Thesis director) / Jugler, Collin (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The brain is considered the crux of identity, yet human behavior may be influenced by bacteria in gut microbiomes. Honeybees can exchange bacteria through their many social behaviors, making their microbiomes, and the effect they have on honeybee behavior, of interest. There is recent evidence suggesting the presence of bacteria existing in human brains, which can be investigated in honeybee brains due to their well-documented structure. The purpose of this study is to establish if lipopolysaccharide—a molecule on bacteria membranes—is present in the honeybee brain and if it colocalizes with vitellogenin—an immune mediator. Additionally, this study also seeks to establish the efficacy of embedding tissue samples in resin and performing immunohistochemistry for vitellogenin and lipopolysaccharide on sections.
ContributorsStrange, Amalie Sofie (Co-author) / Strange, Amalie (Co-author) / Amdam, Gro (Thesis director) / Baluch, Page (Committee member) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Mitochondrial methionyl-tRNA-formyltransferase (MTFMT) is essential for mitochondrial protein translation. The MTFMT gene encodes for an enzyme of the same name, which acts to formylate the methionine of mitochondrial Met-tRNA(Met). In Homo sapiens, MTFMT-formylated-tRNA is an initiator and elongator for the synthesis of 13 mitochondrially-encoded proteins in complexes I, III and IV of the ETC. To understand this mechanism, it is necessary to perform a comprehensive analysis of energy metabolism and oxidative phosphorylation (OXPHOS) among impacted patients. Alterations to this gene vary, with the most documented as a single-splice-site mutation (c.626C>T). Here, we discuss MTFMT involvement in mitochondrial protein translation and neurodegenerative disorders, such as Leigh Syndrome and combined OXPHOS deficiency, in two families. We aim to delineate the impact of OXPHOS dysfunction in patients presenting with MTFMT mutation.
ContributorsChain, Kelsey (Author) / Chen, Qiang (Thesis director) / Rangasamy, Sampathkumar (Committee member) / Narayanan, Vinodh (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05