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hPL Loaded GelMA Microcarriers for the Promotion of Mesenchymal Stem Cell Proliferation
Get PDFThe demand for Human Mesenchymal Stem Cells (hMSCs) has increasingly been growing due to its ability to differentiate into different cell lines, such as adipose, chondrocyte, or osteoblast lineages, thus allowing hMSCs to be widely used for different applications. Due to this increase in demand for hMSCs, different methods are currently being researched to determine effective ways to expand and differentiate hMSCs at a large scale. Current cell culture methods usually require the use of Fetal bovine serum (FBS), but animal-free supplements are important because they are more ethical and have a lower risk of immunoreactions when the cells are used for therapeutic applications. While many options exist such as human serum (hS), platelet-rich plasma (PRP), and other chemically defined media, many studies have shown that human platelet lysate (hPL) supplementation can increase cell proliferation and differentiation comparatively. By comparing plain gelMA to hpL loaded GelMA microcarriers in different serum conditions, many observations were made regarding hPL���s effects on cell proliferation. One of the primary observations made during experimentation was the ability for the cells to attach and proliferate during the span of 24 hrs even without the presence of serum. Upon analyzing these cells, the effect hPL had on cell morphology was noted. Compared to the conditions using plain GelMA, the cells were found to be smaller and skinnier. After counting the cells and microcarriers, the resulting averages of the number of cells per microcarrier in the different conditions came out to 1.21��.35 for PGNS, 1.14��.11 for HGNS, 1.16��.07 for PGS, and 1.27��.38 for HGS. While it was predicted hPL would increase cell proliferation, both types of microcarriers produced similar results when subject to different serum conditions. Even though no definite conclusion can be made about the data, it was seen that loading hPL into the microcarriers produced results similar to the conditions using plain GelMA
Multi-Nodal Control Concepts for a School of Robotic Fish
Get PDFIn the broader scope of studying hydrodynamic interactions within schools of fish, this thesis studies and proposes control frameworks to establish biomimetic robotic replicas for physical experimentation and study. The conventional approach in physical studies of underwater bodies has included the use of struts or tethers for control, accepting various compromises to the faithful representation of the biological subject of the study. This research aims to adapt a previously developed tether-controlled robotic fish called OpenFish into an improved design counterpart called FISHR (Fluid Interaction Study: Hydrodynamic Robot) with a strut-free framework, allowing more faithful scalability for various school sizes and fish types. The design features required to implement a strut-free robotic fish were studied to enable further integration and study of fish schooling mechanics.
The overall control framework relies on the integration of thrust, ballast, and environment sensing systems through an on-board Raspberry Pi processor and Arduino microcontroller to perform high and low-level controls. The Robot Operating System (ROS) on the Raspberry Pi provided a robust foundation for multi-nodal control and performance of common goals across multiple systems. An encoder motor was introduced into the design to provide additional performance data of the FISHR during the fluid study. Two motors with varied capabilities were tested to provide a range of solutions for the primary study. A Light Detection and Ranging (LiDAR) device and miniature camera were also incorporated into the overall design but were not utilized for the purpose of the fluid dynamic field experiments conducted.
Initial experiments were conducted in a deconstructed table-top setup to validate the approaches independently prior to hardware consolidation and integration in the submersible FISHR housing. The findings provided insights into future design requirements for strut-free control of the FISHR system. It also revealed key considerations that represent the inherent challenges of underwater robotics command and control mechanisms. This study lays the groundwork for advancements in underwater robotics and biomimicry by offering a partially successful control framework and the starting blocks to appropriately scale the FISHR prototype design to desired study objectives
A Neurophysiological Exploration of Human Behavior in User-Centered Cybersecurity
Get PDFIn today���s digital era, where security is paramount due to the ever-increasing prevalence of cyber threats, the conventional emphasis on technical cybersecurity measures has evolved towards a more user-centered approach. It has become increasingly apparent that human vulnerabilities and cognitive biases represent glaring weak points in the overall security chain.
This dissertation delves deeply into the crucial intersection of cybersecurity and human cognition within our contemporary digital landscape. While traditional cybersecurity measures undoubtedly play a pivotal role, they often underestimate the significance of the human element, thereby leaving vulnerabilities deeply rooted in cognitive biases and human behavior unaddressed.
Our research resoundingly underscores the pressing need for a paradigm shift toward user-centric cybersecurity solutions. Leveraging the power of neurophysiological methods, specifically the use of electroencephalogram (EEG), we embark on a journey to explore the intricate neural underpinnings of human decision-making in the realm of cybersecurity.
In this dissertation, we tackle the formidable challenges of fake news detection, the identification of deepfake videos, and the design of effective security warnings. Through our re-search, we illuminate the intricate complexities of human decision-making processes and the often-underestimated susceptibility to disinformation, urging a comprehensive reevaluation of traditional cybersecurity strategies
Investigation of the Antimicrobial Activity of Staphylococcus felis C4 Against Staphylococcus pseudintermedius as a Novel Therapy for Canine Superficial Pyoderma
Get PDFCanine superficial pyoderma (CSP) is a common cutaneous disease of dogs, caused primarily by Staphylococcus pseudintermedius. Due to an increase in antimicrobial resistance in the past few years, alternative therapies are necessary to treat this disease. The Staphylococcus felis C4 strain has potent antimicrobial activity against S. pseudintermedius. We inoculated S. pseudintermedius in a new in vitro 3D model of CSP using skin explants, and we observed that both the S. felis C4 live bacterium and its sterile protein product (SPP) significantly and equally reduced the growth S. pseudintermedius. We then evaluated the safety of both S. felis C4 live bacteria and its SPP by applying it to the abdominal skin of five healthy dogs. Four out of five dogs of the live bacteria experiment developed pustules and erythema on the treatment side of the application, and no pustules were seen in the placebo side. On the other hand, no skin lesions were seen in the abdominal skin of dogs that received the SPP. We concluded that the S. felis C4 live bacterium is not safe to be applied in dogs in its current formulation, while the SPP is safe. Finally, we recruited six dogs with CSP for a randomized, double-blinded, placebo-controlled clinical trial, where we tested the potential of S. felis C4 SPP to be used as an alternative therapy. The dogs received treatment for 7 days, twice a day, daily, and were followed-up for one month. There were no statistical differences in the treatment and placebo groups with regards of lesion severity, number of bacterial colonies isolated, overall amount of bacterial DNA, and amount of Staphylococcus sp. DNA. We concluded that, despite the strong in vitro antimicrobial activity of S. felis C4 SPP, the active product in its current formulation, drug delivery system, and dosage is not effective in treating dogs with superficial pyoderma
Ticks and Other Ectoparasites of Small Mammals and Birds Inhabiting the Madrean Sky Islands of Southern Arizona, USA
No full textThe Madrean Sky Islands of southern Arizona are home to a wide diversity of birds, mammals, and other animals including the under studied tick species Amblyomma maculatum sensu lato which has been associated with human cases of Rickettsia parkeri rickettsiosis. To better describe the natural history and to build upon the limited existing knowledge of this tick, we live trapped small mammals and birds and examined them for ectoparasites, described and monitored the microclimates of a higher elevation canyon site and a lower elevation riparian corridor where this tick species is commonly found, and compared three different collection methods to collect them from the environment.
Two study sites were sampled where adult ticks had been previously reported. All ectoparasites were collected from vertebrates. Out of 11 small mammal species encountered, Sigmodon arizonae were the most ectoparasite-infested animals captured, and they harbored more immature ticks than any other host species. There were 39 species of birds encountered during this study, with 23 individuals out of 254 birds captured found with ectoparasites, and 15 of the 23 individuals (composed of 7 different avian species) were infested with 23 A. maculatum s.l.
Microclimate data from sites showed warmer temperatures and lower humidity were observed at the canyon site as compared to the river. Observations and collections of adult ticks coincided with the monsoonal weather pattern which occurs annually in Arizona and significantly raises the relative humidity.
Finally, of the three tick collection techniques for collecting questing A. maculatum s.l. from the environment the most ticks were collected using the sweep net as compared with flagging or dragging
The Impact of Mineral Levels and Sources on Necrotic Enteritis Pathogenesis in Broilers
No full textThis dissertation���s objective was to evaluate the influence of minerals (level and source) to determine their influence on necrotic enteritis (NE) pathogenesis and broiler performance, following a coccidia vaccine. Three experiments were conducted. The first experiment was to determine the impact of calcium (Ca) and magnesium (Mg) on the pathogenesis of NE. The second experiment was to evaluate the effects of manganese (Mn), copper (Cu), and zinc (Zn) supplementation on NE pathogenesis and performance. The third experiment was to determine the influence of Mn, Cu, and Zn supplementation on NE pathogenesis, performance, and environmental sustainability.
In experiment one, there was a two-way interaction between Ca source and Ca level throughout the trial (d 0-30). Feeding Ca source, CalMin, resulted in the most significant performance losses, specifically when Ca was fed at the higher inclusion level. Birds fed CalMin at the higher Ca inclusion level resulted in reduced average body weight, body weight gain, and feed intake, as well as an increased feed conversion ratio and percent mortality when compared to all other dietary treatments.
In the second experiment, there was a two-way interaction between mineral premix and phytase level throughout the trial (d 0-31). Feeding birds an all-inorganic diet or combination of inorganic and organic mineral diet at the lower phytase level (500 FTU/kg) resulted in the lowest d 0-14 body weight and body weight gain, as well as the lowest d 15-31 and d 0-31 feed intake. Birds saw improvements in performance when fed an all-organic diet (regardless of phytase level) and when the all-inorganic diet and combination of inorganic and organic mineral diet was super dosed with phytase (1500 FTU/kg).
The third experiment exhibited improvements in performance for all mineral premixes when phytase was super dosed (1500 FTU/kg). Broilers fed an all-organic diet when super dosed with phytase had the most efficient d 0-15, d 31-42, and d 0-42 feed conversion ratio. Birds fed an all-organic diet resulted in a significantly lower Mn concentration in the fecal and litter samples. However, birds fed the combination of inorganic and organic minerals, or an all-organic diet resulted in significantly lower Cu and Zn concentrations in the fecal and litter samples.
Research needs to be conducted to better understand how Clostridium perfringens can lead to NE as it continues to negatively impact the poultry industry. Minerals, specifically source and inclusion level should also be investigated. Learning more about the influence of these bacterial strains and how diet can aid in mitigating NE is crucial in improving animal welfare and preventing economic losses
The Experiences of Women of Color in Trio Programs: A Systematic Literature Review
No full textDespite America's strong college enrollment and completion rates, first-generation college students still face disparities. TRIO programs were designed to meet this group's expanding requirements and alleviate barriers to their access and completion of higher education. Literature is developing on TRIO's success, but there remains a dearth of disaggregation on specific first-generation populations' perspectives of TRIO's effectiveness. The purpose of this systematic literature review is to examine perspectives from first-generation women of color TRIO participants. The review found 29 studies, revealing six analytical themes indicating how TRIO programs play a pivotal role in providing a supportive ecosystem for them. The themes include high school performance and college preparation, academic preparation, social preparation, TRIO help with career and educational goals, TRIO help finish college, and problems in college for FGWoC. Implications serve as a vital compass for policy development and program enhancement within the TRIO community, university administration, and student centers/organizations
