Novel Cationic Pentablock Copolymers as a Nanovaccine Delivery Platform

The main objective of this project is the development of a safe and effective vaccine against respiratory pathogens including the highly pathogenic avian influenza (HPAI) H5N1. Amphiphilic pentablock copolymers based on Pluronic F127 and poly(2-diethylaminoethyl methacrylate (PDEAEM) have several characteristics that make them promising candidates as injectable vaccine carriers and adjuvants. Individual block copolymer molecules self-assemble into micelles in aqueous solutions. These micelles can be used to encapsulate protein for vaccine delivery. As the concentration of the block copolymer increases, the micelles form a temperature dependent gel and the length of the PDEAEM blocks control the dissolution rate of the gels. An injectable formulation can be designed to gel at physiological temperatures and form an antigenic depot. In addition, these biocompatible pentablock copolymers are based on pluronic, which is FDA approved as an injectable material. In order to design an efficacious next-generation vaccine against HPAI H5N1 several specific research goals were laid out including: (1) Design, synthesis, and optimization of the pentablock copolymer vaccine platform; (2) Evaluation of vaccine efficacy in vitro and in vivo; and (3) Immunization of mice with the pentablock copolymer vaccine to asses an immune response. Our block copolymer injectable delivery platform demonstrates the ability to sustain the release of antigen with minimal effects on protein stability or antigenicity and persist at the injection site. We have also successfully modified the polymers through an azide-alkyne click reaction to include mannose moieties that act as ligands for pattern recognition receptors on antigen presenting cells. These data coupled with the strong immune response demonstrate the potential for block copolymers for use simultaneously for injectable delivery and as a vaccine adjuvant platform

A water distribution and treatment simulation for testing cyber security enhancements for water sector SCADA systems.

Supervisory control and data acquisition (SCADA) systems are used by many critical infrastructures including electric power production and distribution, water and waste water treatment, rail transportation, and gas and oil distribution. Originally isolated proprietary systems, SCADA systems are increasingly connected to enterprise networks and the Internet and today use commercial hardware and software. As a result SCADA systems now face serious cyber-security threats. The need for testing and evaluation of developed cyber-security solutions presents a challenge since evaluation on actual systems is usually not possible and building complete physical testbeds is costly. This thesis presents the design and development of a water systems simulation for testing and evaluation of cyber-security enhanced field devices. The simulation consists of two main parts: a human machine interface/master terminal unit (HMI/MTU) component and a water treatment and distribution component. The HMI/MTU part supports new security protocols used to communicate with the hardened remote terminal unit (RTU). The water system simulates a water treatment and distribution center. A data acquisition (DAQ) module was used in conjunction with LabVIEWTM to create a water distribution and treatment simulation that could be interfaced with an actual field device. Field device I/Os are wired to the DAQ which then interface with the LabVIEWTM simulation. The simulation supports: selectable polling of I/O, graphical representation of I/O, random water usage, constant water usage, and simulation data collection. The simulation uses a modular design pattern so that it can be easily extended in the future. Initial testing with a hardened RTU prototype confirmed the ability of the simulation to interact with real hardware and identified some minor errors in the prototype’s security protocol implementation. With additional DAQ devices the simulation could be extended to simulate larger water systems

The Invincible (1758) site: an integrated geophysical assessment

Chirp sub-bottom profiler and repeat sidescan sonar imaging of the Invincible wreck site (1758) in the Solent (U.K.), interpretation, and implications for management of the site

The Feasibility of Detecting Supercooled Liquid with a Forward-Looking Radiometer

A three-dimensional radiative transfer model is utilized to determine the feasibility of a forward-viewing passive sensor for remotely detecting hazardous icing conditions. Wband ground-based radar simulations show no obvious ability to discriminate a cloud-top supercooled layer; however, the spectra for a forward-viewing passive sensor show a strong signal at two stand-off distances when compared with the clear sky spectrum. Such an instrument would be critical for manned and unmanned aircraft, particularly when size, weight, and power requirements restrict the installation of deicing equipment

A Tale of Two Sylamores: Understanding Relationships Among Land Use, Nutrients, and Aquatic Communities Across a Subsidy-Stress Gradient

Agricultural land use is known to degrade aquatic systems with high inputs of nutrients, sediments, and pesticides. Increased nutrients can lead to increased algal growth and thus possible hypoxic conditions in slow moving water, while increased sediment loads have been shown to obstruct light and reduce substrate stability. These conditions negatively impact primary producers, macroinvertebrates, and fish. However, small-scale changes in land use can subsidize an aquatic ecosystem instead, where an increase in nutrients allows nutrient-limited biota to flourish, and minor increases in sedimentation may help support populations of collector-filterers. The stimulation in performance caused by small disturbances is part of the subsidy-stress gradient, where increasing perturbation subsidizes an ecosystem until a certain threshold is reached, at which a decline in performance and increased variability starts to occur. The North and South Sylamore watersheds in north Arkansas provide a useful template to investigate the subsidy-stress gradient in relation to land use. North Sylamore flows through the Ozark National Forest and has a heavily forested catchment, while South Sylamore flows through mostly private land, some of which is pasture (23%). Physicochemical, macroinvertebrate, and fish data were collected from multiple sites within each watershed to determine if South Sylamore is exhibiting a response to pasture/agriculture characteristic of a subsidy-stress gradient. Sites within South Sylamore had significantly higher nitrate levels, larger macroinvertebrate populations dominated by collector-filterers, and greater abundance of algivorous fish, suggesting South Sylamore may be subsidized by the surrounding pastoral lands. However, South Sylamore also had a significantly lower proportional abundance of sensitive macroinvertebrate taxa and more unique tolerant fish taxa, suggesting South Sylamore is experiencing stress as well. Habitat quality of South Sylamore could be improved by restoration of trees within the riparian zone. Monitoring aquatic systems for subsidy-stress responses can inform restoration/management decisions and guide intervention prior to watersheds and aquatic communities becoming overly stressed

A Narrative Study Of Black Males Sense Of Belonging In Graduate Counseling Programs

The purpose of this narrative study was to understand the experiences of Black males in doctoral counselor education programs. The study aimed to build a dialogue based on participant’s experiences growing up as Black males, and how they experienced sense of belonging in their counselor education programs. This narrative study utilized a purposive and homogenous sampling selection. Black males who were selected to participate in this study attended Predominantly White Institutions and were in the process of earning their doctoral degrees in counselor education. Each male was a full-time student, in either their second, third or fourth year of their program. Narrative Theory, Critical Race Theory, and the Historically Black College and University (HBCU) Educational Models were identified as theoretical frameworks to understand participants’ experiences. Participants’ narratives were constructed using a Three-Dimensional Space Approach and told in Chronological order structured with a beginning, middle, and end. Black males experienced lower levels of sense of belonging while completing doctoral counselor education degrees at Predominantly White Institutions. Identifying as a Black male played a role in how they perceived sense of belonging at their institution. In addition, findings developed themes that aligned with Narrative Research and Critical Race theory tenants of (a) Centrality to Race & Racism/Externalizing the Problem, (b) Challenges to Dominate Ideology/Counter-Narrative and (c) Experiential Knowledge/Linking. Findings of these tenants included suggestions about how universities can improve sense of belonging among Black males in doctoral counselor education programs. This study has implications for counselor education programs, clinical mental health professions, and future research studies. White faculty members and White counselors should develop a deeper understanding of the racial and cultural needs to become aware of appropriate techniques to create healthy relationships with Black males. Moreover, this study created a more extensive voice of Black males in counselor education to raise awareness for the need for a restructured curriculum and development of mentoring and support programs. Finally, this study allowed more profound understanding of Black male’s experiences of sense of belonging in doctoral counselor education programs at Predominantly White Institutions, Counselor Education Programs, and traditional systemic higher education structures

Integrating Selective Herbicide and Native Plant Restoration to Control Alternanthera philoxeroides (Alligator Weed)

Exotic invasive aquatic weeds such as alligator weed (Alternanthera philoxeroides) threaten native ecosystems by interfering with native plant communities, disrupting hydrology, and diminishing water quality. Development of new tools to combat invaders is important for the well being of these sensitive areas. Integrated pest management offers managers an approach that combines multiple control methods for better control than any one method used exclusively. In a greenhouse and field study, we tested the effects of selective herbicide application frequency, native competitor plant introduction, and their integration on alligator weed. In the greenhouse study, alligator weed shoot, root, and total biomass were reduced with one herbicide application, and further reduced with two. Alligator weed cumulative stem length and shoot/root ratio was only reduced after two applications. In the greenhouse, introduction of competitors did not affect alligator weed biomass, but did affect shoot/root ratio. The interaction of competitor introduction and herbicide did not significantly influence alligator weed growth in the greenhouse study. In the field, alligator weed cover was reduced after one herbicide application, but not significantly more after a second. Introduction of competitor species had no effect on alligator weed cover, nor did the interaction of competitor species and herbicide application. This study demonstrates that triclopyr amine herbicide can reduce alligator weed biomass and cover, and that two applications are more effective than one. To integrate selective herbicides and native plant introduction successfully for alligator weed control, more research is needed on the influence competition can potentially have on alligator weed growth, and the timing of herbicide application and subsequent introduction of plants