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03. Halloysite Animal Hair Coating Optimization for Efficient Anti-lice Protection
No full textWe demonstrate enhanced immobilization of halloysite tubule nanoclay onto hair surfaces of different mammals including horses, goats, and capybaras and search for the features that allow stable coating with drugs for anti-parasitic protection. Deposition of hair coverage with a micrometer nanotubes’ layer loaded with drugs allows for sustained delivery. Halloysite clay nanotubes are natural, safe, and biocompatible materials. Halloysite self-assembles on the hair surface during a 3-minute application of its aqueous colloids resulting in 2-3 µm thick coating. I referenced Dr. Lvov’s work for this experiment and investigated the topography of animal hair halloysite coatings using 3D laser confocal scanner and SEM. Enhanced animal hair hydrophobicity resulted in more stable nanoclay layers. After being loaded with permethrin, halloysite provides a slow release over 5-10 days which is promising for long-lasting anti-parasitic protection.
Halloysite act as a carrier for anti-lice drug delivery by readily attaching to hair allowing for targeted delivery. Water-insoluble drugs such as permethrin can be encapsulated into the anionic amphiphiles modified clay tube’s lumens followed by its aqueous colloid application on hair. Lice harm animals by causing skin diseases, anemia, and death in some cases. Many anti-parasitic treatments are not effective because are quickly removed from hair. I collected goat lice samples and elaborated the experiments on topical anti-lice nanoclay drug delivery on goat and horse hair. It is currently in progress with comparison: 1) lice culture on hair, 2) lice on hair treated with pure permethrin, and 3) hair coated with halloysite nanotubes loaded with the drug
07. Initiation Into Sisterhood: An Examination of Transgender Women Doing and Undoing Gender in an American Sorority
No full textTaking from the experiences of transgender women, this research proposal analyzes West and Zimmerman’s sociological theory of “doing gender” within Panhellenic sororities on American college campuses. The transgender community is becoming more prominent thus breaking the socially constructed idea of there being only the binary, man and woman. As the transgender population is increasing within American society, it is important to address how their day-to-day interactions with the world socialize their gender performance. The results of this study will be determined through recorded in-depth interviews with questions that emphasize the decision to join a sorority, the formal recruitment process, and the experiences once having gained membership. After performing and transcribing the interviews, I will code each of them to draw specific commonalities and themes that arise from these detailed discussions. The overall goal is to discover how a transgender woman displays her gender to her fellow cisgender sisters, whether that be through clothing, conversation, or other factors. Though this research question has yet to become answered, it will hopefully bring awareness of inclusion and diversity to college campuses and how they can benefit members of the transgender community in not only their post secondary education but also their experiences at their institution
04. Recreating 19th century Regency Headwear with 21st Century Materials and Tools
Get PDFThe question I am trying to answer through my research and work is how can we recreate 19th century Regency Headwear with 21st century materials and tools. This project is important to me due to the fact that I am a costumer who seeks to find ways to make past century costume styles relevant with the current style of the 21st century. With the help of my costume advisor, Michele Dormaier, we found different 19th century Regency Headwear sewing patterns that would allow for the use of modern materials and tools. The method that was used while researching was to find headwear patterns that were for the 19th century while also researching if said pattern would be achievable with the use of 21st century sewing materials and tools. When a pattern fit both of those requirements, it was then printed to be more organized and accessible. The results of the research conducted were three different versions of a 19th century Regency Headwear: The Wrapped Turban, the Cap Turban, and the Rope Turban. Each style of turban offers a new technique of building a Regency Headwear from the 19th century with modern materials from the 20th century. My results helped reconfirm my goal to promote the relevance of past century costume styles in today’s society by demonstrating all of the possibilities that can be achieved. My findings motivated me to continue with my goal by finding patterns that showcase how it is possible to create clothing from the past with materials of the present
The Impact of Block Scheduling on Student Achievement, Graduation Rate, and Attendance at the High School Level
Get PDFThe purpose of this study was to determine the impact of block scheduling on student achievement, graduation rate, and attendance at the high school level. The study was a mixed methods study that compared existing data from three high schools from the same school district in a southern state which all moved from a traditional schedule to a block schedule and back to a traditional schedule over the same period of time. The study results included the comparison of composite ACT scores and attendance rates from the years pre-block implementation, the years of block implementation, and the years post-block implementation. The comparison of graduation rate data was limited to the years of block implementation and post-block implementation. An Analysis of Variance, ANOVA, was utilized to assess the impact of block scheduling on composite ACT scores, graduation rates, and attendance rates. For the qualitative portion of the study, administrators who served at the schools during the three time periods were interviewed. Their responses were recorded and analyzed and common themes and differences were noted. The results of the analysis of the quantitative data indicated that there was no statistical difference in the composite ACT scores and attendance rates between students on a block schedule and those on a traditional schedule. The results of the analysis of graduation rates indicated that there was a statistical difference between students on a block schedule and those on a traditional schedule, with students on a traditional schedule performing better
Characterization Of Commercially Available Conductive Filament And Their Application In Sensors And Actuators
Get PDFThe primary aim of this study is to contribute to the field of additives that would enable the fabrication of electrical sensors and actuators completely via Material Extrusion based Additive Manufacturing (MEAM). The second aim of the study is to provide the necessary characterization to facilitate the development of applications that predicts electrical part performance. The electrical characterization of two conductive poly-lactic acid (PLA) filaments, namely, c-PLA with carbon black and graphene PLA was performed to study the temperature coefficient of the resistance. Resistivity of carbon black filament was compared to a printed single layer and with that of a cube. The raw and printed c-PLA showed a positive temperature coefficient of resistance (α) ranging from ~0.03-0.01 ℃-1 while its counterpart in the study, graphene PLA, did not exhibit significant (α). Parts from graphene PLA with multilayer MEAM exhibited a negative α to a certain temperature before exhibiting positive α. The resistivity of the printed parts was 300 times higher for c-PLA and 1500 times for graphene PLA. However, no microstructural or chemical compositional changes were observed between the raw filaments and the printed parts. Due to the high α of the c-PLA, it was deemed as the better material for constructing electro thermal sensors and actuators using MEAM.
First, c-PLA was used to fabricate and package a completely 3D printed flow meter that operates on the principle of Joule heating and hotwire anemometry. When the designed flowmeter was simulated using a finite element package, a flow sensitivity of -2.33 Ω sccm-1 and a relative change in resistivity of 0.036 sccm-1 was expected. For an operating voltage of 12-15 V, the experimental results showed a flow sensitivity within the range of 0.014-0.032 sccm-1 and the relative change in resistivity ranged from 0.039 – 0.065 sccm-1. Thus, a completely 3D printed flowmeter was demonstrated. Second, using the same principle of Joule heating, an actuator inspired from MEMS chevron grippers was designed, simulated, and fabricated. Simulation showed the feasibility of the structure and further predicted a displacement of a few hundred microns with a potential as low as 3 V with a cooling time as little less than 120 seconds. Experimentally, a displacement of 120.04, 97.05, and 88.96 μm were achieved in 15, 10, and 5 seconds with actuation potentials of 12.7, 13.8, and 17.9 V, respectively. As predicted by the simulation results, it took longer for the gripper to cool (close to 180 seconds) when compared to actuation times.
During the above studies, we discovered the printing parameters altered the part resistance. Our final study examined how extrusion temperature and printing speed affects the impedance of the MEAM printed parts. Further, anisotropy in the impedance was observed and the influence of the interface to it was examined. From the experimental results, the anisotropy was quantified with a Z/F ratio and was found to be nearly constant, ~2.15±0.23. Impedance scaling with the number of interfaces was measured and showed conclusively that the interlayer bonding was the sole source for the observed Z/F ratio. Scanning electron microscope images shows the absence of air gaps at the interface, and energy dispersion spectroscopy shows the absence of oxidation at the interface. By investigating the role of print parameters and scaling of impedance with interfaces, a framework to model and predict electrical behavior of electro thermal sensors and actuators made via MEAM can be realized
ExoPRIME technology for exosomal miRNA analysis and identification of oxidative DNA damage-induced miRNA regulatory network in human astrocytes
Get PDFThe high lipid content of the brain, coupled with its heavy oxygen dependence and relatively weak antioxidant system, makes it highly susceptible to oxidative DNA damage that contributes to neurodegeneration. This study assesses and compares the neurotoxic effects of proton and photon radiation on mitochondrial function and DNA repair capabilities of human astrocytes. Human astrocytes received either proton (0.5 Gy and 3 Gy), photon (0.5 Gy and 3 Gy), or sham-radiation treatment. The mRNA expression level of the human base-excision repair protein, 8-deoxyguanosine DNA glycosylase 1 (hOGG1) was determined via RT-qPCR. Radiation-induced changes in mitochondrial mass and oxidative activity were assessed using fluorescent imaging with MitoTracker™ Green FM and MitoTracker™ Orange CM-H2TMRos dyes, respectively. A significant increase in mitochondrial mass and levels of reactive oxygen species was observed after radiation treatment. This was accompanied by a decreased OGG1 mRNA expression. These results are indicative of a radiation-induced dose-dependent decrease in mitochondrial function, an increase in senescence and astrogliosis, and impairment of the DNA repair capabilities in healthy glial cells. Photon irradiation was associated with a more significant disruption in mitochondrial function and base-excision repair mechanisms in vitro in comparison to the same dose of proton treatment. This study further identifies specific ROS-responsive miRNAs that modulate the expression and activity of the DNA repair proteins in human astrocytes, which could lead to the development of targeted therapeutic strategies for neurological diseases. Oxidative DNA damage was established after treatment of human astrocytes with 10 μM sodium dichromate for 16 hours. Comet assay analysis indicated a significant increase in oxidized guanine lesions. PCR analysis confirmed that sodium dichromate reduced the mRNA expression levels of hOGG1. Small RNAseq was performed on an Ion Torrent™ system and the differentially expressed miRNAs were identified using Partek Flow® software. The biologically significant miRNAs were selected using miRNet 2.0. Oxidative-stressinduced DNA damage was associated with a significant decrease in miRNA expression: 231 downregulated miRNAs and 2 upregulated miRNAs (p \u3c 0.05; \u3e 2-fold). In addition to identifying multiple miRNA-mRNA pairs involved in DNA repair processes, this study uncovered two novel miRNA-mRNA pairs interactions: miR-1248:OGG1 and miR-103a- OGG1. Inhibition of miR-1248 and miR-103a via the transfection of their inhibitors restored the increased expression levels of hOGG1. Therefore, targeting the identified microRNAs could ameliorate the nuclear DNA damage caused by exposure to mutagens. The miRNA candidates identified in this study could serve as potential biomarkers and therapeutics for oxidative stress in the brain to reduce the incidence and improve the treatment of cancer and neurodegenerative disorders. In a parallel but closely related study, we report a direct, one-step exosome sampling technology, for selective capture of CD63+ exosome subpopulations using an immune-affinity protocol. The ExoPRIME microprobe provides a Precise Rapid Inexpensive Mild (non-invasive) and Efficient (i.e. PRIME) alternative to the conventional polymer precipitation-based methods by enriching a comparatively more homogenous exosome population. The tool consists of an inert Serin™ stainless steelz microneedle (300 μm in diameter × 30 mm in height), pre-coated with a thin-film polyelectrolyte layer that serves as a substrate for covalent bonding of biotin. An anti-CD63 steptavidin-conjugated antibody that selectively binds to the corresponding tetraspanin embedded in the lipid bilayer of exosomes was immobilized to the outer surface of the probe. The feasibility of the ExoPRIME technology was validated using two types of biological samples: conditioned astrocyte medium (CAM) and astrocyte-derived exosome suspension (EXO). The study investigated the impact of the temperature (4°C and 22°C) and incubation duration (2h and 16h) on the capture efficiency of the ExoPRIME tool. A fluorescence-based enzymatic assay for exosome quantification was used to assess the probe’s exosomes capture efficiency and the reproducibility of the technology. The low level of non-specific binding initially observed in non-functionalized microneedles was drastically minimized by blocking the ExoPRIME probe with 0.1% BSA. The ExoPRIME microprobe captured exponentially more exosomes than the non-functionalized microneedle that indicates enrichment of CD63-expressing exosomes. A major advantage provided by the ExoPRIME technology over existing platforms is its applicability over a broad dynamic range of temperature and incubation parameters without compromising the purity and viability of exosomal cargoes. The loading capacity of the probe increased after incubation for 16 h at 40C in exosome suspension (24Å~106 exosomes per probe) while the efficiency decreased 10 folds after 2 h at 40C (24Å~105 exosomes per probe). The increase in temperature had an impact on the stability of the reagents that contributed to a 2-fold efficiency reduction after incubation in exosome suspension for 16 h at 220C (12Å~106 exosomes per probe). However, the 2-hour roomtemperature incubation (2 h at 220C) of the ExoPRIME probe yielded an increased capture efficiency (12Å~106 exosomes per probe) when compared to the 2 h at 4°C incubation (24Å~105 exosomes per probe). These results suggest that lower temperatures with extended incubation times constitute the most optimal parameters that ensure high probe loading capacity. Another advantage of the ExoPRIME microprobe is that it captures antigen-specific subpopulation of exosomes directly from conditioned astrocyte medium (CAM), eliminating the requirements for additional filtration and pre-concentration, and thereby cutting down costs and handling time. Besides the relatively reduced number of enriched exosomes, the CAM results are consistent with the trend obtained for EXO incubations, a phenomenon that could be attributed to the presence of various extracellular proteins and cellular debris, which could mask antibodies and compete physically with exosomes for binding. The capabilities to integrate different incubation times, temperatures, and biofluid type thus present exosome researchers with the flexibility to choose the combined parameters that best suit their purpose, the desired factor in clinical and laboratory applications. The developed tool requires very low amounts of antibody, permits the use and reuse of minimal sample volumes (≤ 200 μL), can be multiplexed in arrays to diagnostically profile multiple exosome classes and is amenable to integration into a lab-on-a-chip platform to achieve parallel, high-throughput isolation in a [semi]-automated workstation. Moreover, this platform could provide direct exosomal analysis of biological fluids since it can elegantly interface with existing picomolar-range nucleic acid assays to provide a clinical diagnostic tool at the point of care and facilitate fundamental studies in exosomes functions
Investigation of Control Parameters, Strategies, and Transport Modeling for Effective Electrokinetic Nanoparticle Treatment of Cementitious Materials
Get PDFVarious deleterious chemical species (including sulfates, chlorides, and others) contaminate concrete structures which are inherently porous and thus suffer from compromised durability. Several technologies have been developed for repairing concrete or enhancing the service life. Nevertheless, their efficiency, practicability, and cost can vary widely. Compared with chemical grout, fiber wrap, and traditional repair technology, electrokinetic nanoparticle treatment (EN) has been found to provide remarkable benefits for strength restoration and mitigation of durability problems via porosity reduction. Nanoparticle instability and over dosage issues can arise and lead to problems during treatments. In many cases, these treatment processes have been accompanied by significant particle losses and are known to cause deficiencies in treatment effectiveness. To deal with these unstable and low effectiveness issues, this dissertation was conducted to explore new electrokinetic nanoparticle treatment strategies to transport nanoparticles into concrete and cement effectively and efficiently. This study developed new methods involving simple tools (Turbidity, pH, and specific gravity) to monitor and sustain suspension stability. These tools made it possible to amend a given dosing strategy, as needed, in real-time. Other types of treatment adjustments were also examined. For example, a new turbidity monitoring method was developed to track the visually imperceptible phenomena of particle flocking early on, at the inception of its development, before it could harm a treatment outcome. A relationship between the turbidity and the specific gravity was developed to facilitate early detection of particle flocking. The tools, guidelines, and strategies achieved in this study were developed to enable the management of efficient (low-particle-loss) electrokinetic nanoparticle treatments by signaling in real-time when adjustments to the electric field, pH, and particle dosage increments were needed. High alumina cement specimens were subjected to EN treatment by determining the effect of using a low-concentration dosing strategy. The resultant impacts on compressive strength improvement (33%), porosity reduction (6.7% to 4.1%), and abrasion resistance enhancement (20%) indicated a relatively high effectiveness in particle delivery during the treatment. This was achieved even through the starting porosity value of the HAC were relatively low. A nanoparticle shockwave model was adapted from traffic control theory and modified to simulate particle transport behavior during EN treatment. This model was used to determine real-time particle mobility and predict a reliable treatment time for a given EN treatment. This predicted time was within 9% of the actual treatment time. A Front Area Ratio (FAR) model was also developed to predict the likelihood of a nanoparticle traffic jam and assess stability risks. This work also characterized the transport behavior of commercially available particles (NALCO 1056 (24 nm), Grace CL (12 nm), and Grace CL-P (22 nm)). These treatments were all found to effectively reduce porosity from 25% to 18% in average, and increased the compressive strength by 37% for ordinary Portland hardened cement paste specimens. The unit volume porosity reduction cost of utilizing the Grace CL-P particle was found to be 6 times lower than the NALCO 1056 applications. Both pH-inducedcollapse thresholds and thermal stability thresholds for each particle were determined to understand these impacts on treatment outcomes. To address electric field limitations, an alternative treatment circuit was developed to manage electrolysis-induced pH changes. This alternative treatment geometry increased the anode surface area by 120% and effectively stabilized particles while raising the threshold electric field value as high as the concrete damage current density threshold of 1 A/m2
Her
Get PDFAlayna Juneau is a senior in interdisciplinary studies at Louisiana Tech University. She is passionate about telling stories through any medium. Her favorite things to do are pet cats, take naps, and play video games. She hopes to one day be a game developer, a writer, or a crazy cat lady
He Does the Things He Does
Get PDFAnthony Franklin began his creative writing career in eighth grade after reading The Tell-Tale Heart by Edgar Allen Poe. Self expression through ink on paper is enthralling to him. He hopes to master this medium of expression, becoming the best writer he can be, throughout college and beyond
To the Practice of Both
Get PDFAddy Lindsay is a second year student at Louisiana Tech University. She is studying psychology with a minor in sociology and a minor in family and child studies. She hopes to become a clinical trauma therapist in the future. Addy enjoys drinking coffee with friends, listening to podcasts, writing, and learning new things