Insects have superlative capabilities over contemporary robots: increased mobility, redundancy, coverage area, and can utilize different sensors. Perhaps most importantly, having reduced mass, launch costs can be exponentially lower. The goal of my research project was to create a simulation to compute the pathway/logistics of an insect robot landing on Mars, code a simulation, linearize data and arrays, and learn more about insect robots and space to investigate how to land insect-sized flying robots on Mars. I first reviewed existing information on spacecraft transiting from Earth to Mars, including the need to protect insect-sized robots from space and radiation while in transit. Of great interest would be potentially different de-orbiting and landing scenarios given a lower mass spacecraft, which is still traveling a hundred times faster than a bullet during initial deorbiting. My research speculated that simpler landing strategies like Spirit and Opportunity vs Endurance might be employed for the carrier spacecraft, and once on the surface, a carrier could deploy a small rover to act as a home base supplying power and communications to the flying insect-sized robots, greatly extending the range of the science data collection. My research captured the general characteristics of insect robotics and using a Python program I created, simulated reentry paths and maximum heating rates, which were still high as expected. My next steps would be to test different ballistic coefficients to see if a small payload direct from deorbit landing is possible. The broader implication is the potential for delivering many tiny distributed sensors on Mars to dramatically improve our understanding of the planet and at a lower cost.

Development and testing of sensors and power methods for insect-based robots is a difficult task. Due to the high cost of manufacture with regards to both training time and funds, finding a sustainable and easy-to-produce method to test sensors and power options is essential. Previously, the only option for testing new sensors and power options was using one of the robotic insects, which is risky considering their high costs. Drawing from prior results, we believe a lightweight quadcopter would be faster, easier to produce, more robust, and able to serve as a suitable replacement in sensor testing and development. My goal will be to create the world's lightest and smallest quad-rotor helicopter, “TinyQuad,” with a target mass of 1–2 g. The new helicopter I have designed will enable the testing of new sensors such as cameras and power options such as radio frequency-based charging. This design allows for testing a variety of sensors and electronics configurations very quickly, with the potential to rapidly speed up the prototyping process. I will demonstrate flight capabilities through utilizing wireless charging, and sensor-based feedback control to improve flight stability and duration. I completed calculations and design of this hardware, and anticipate seeing that the collected flight data supports the utilization of a lightweight quadcopter in insect robotics development. This will allow us to rapidly develop and refine sensors for use onboard the RoboFly robotic insect platform. Creating a working quadcopter would result in accelerated prototyping that allows for more unusual sensor and payload designs, and for further research in developing new sensors and power methods for insect robotics, smaller quadcopters, and improved design of micro aerial vehicles.

Nucleic-acid based vaccines, including RNA and DNA, provide protective immunity by eliciting antibody (Ab), and cytotoxic T lymphocyte (CTL) responses. FDA approval of mRNA vaccines against SARS-CoV-2 (COVID-19) provide ample evidence that mRNA vaccines are a viable vaccine platform. Once a mRNA vaccine enters a cells cytoplasm, mRNA encoded antigens are produced rapidly inducing an immune response. The production of mRNA encoded antigens will wane over time as mRNA degrades and transfected cells die. Alpha viruses, a RNA virus, have a unique replication process whereby this virus amplifies its RNA genome upon entering a cell. We, as well as others, have developed RNA vaccines that, like alpha viruses, self-amplify once inside of a cell to create more copies of mRNA than entered cell. This self-replicating RNA vaccine is called a replicon RNA vaccine (repRNA). RepRNA induces robust and sustained antigen production and immune responses. Currently, mRNA vaccines are administered as a homologous prime/boost vaccine regimen where the same mRNA vaccine is given as a priming vaccine and boosting vaccine, but antibody titers wane over time allowing for potential infections. This project aims to evaluate If utilizing a heterologous prime/boost regimen with DNA and repRNA vaccines confers more robust and longer lasting antibody and CTL responses than homologous regimens with DNA or repRNA. Mice will be vaccinated with DNA as a priming vaccine and repRNA as a boosting vaccine that encode SARS-CoV-2 spike protein. Anti-SARS-CoV-2 spike IgG antibody titers will be measured at 3-4 different timepoints, and CTL responses will be evaluated using an interferon gamma (IFN-γ) enzyme-linked immune absorbent spot (ELISpot) assay. The insights gained from this project will help to inform future DNA vaccine formulations and regimens as more DNA vaccines and repRNA vaccines enter clinical trials.

In this study we developed a nonhuman primate model of simian immunodeficiency virus (SIV)-Zika virus (ZIKV) co-infection to understand how HIV infection impacts ZIKV pathogenesis and test our hypothesis that ZIKV pathogenesis is enhanced in people living with untreated HIV. Previously, we have found delayed viral clearance, as well as delayed and dampened expansion of whole blood monocytes, the ZIKV cellular targets, during SIV infection. Here, we sought to further characterize the innate immune responses of SIV-ZIKV co-infection, by assessing cytokine and chemokine release. Pigtail macaques (n=7) were infected with SIVmac239M and co-infected with ZIKV at 9 weeks post-SIV infection. Co-infected animals were compared to control animals (n=7) infected with ZIKV only. Longitudinal plasma and cerebral spinal fluid (CSF) were collected at timepoints pre- and post-infection and assayed using a multiplex immunoassay to quantify 24 different cytokine and chemokines ex vivo. SIV and ZIKV both induced pro-inflammatory responses, characterized by transient increases in interleukin-17 (IL-17A) and monocyte chemoattractant protein-1 (MCP-1), with no major differences between experimental groups. Plasma MCP-1 concentrations were also found to be consistent with dampened and delayed whole blood monocyte frequencies. Pro-inflammatory interleukin-8 (IL-8), a chemokine needed for recruitment of neutrophils, increased in the plasma during SIV infection but not following ZIKV infection, a result that is in contrast to our previous findings. Transient increases in IL-8 were detected in a few animals in the CSF after ZIKV infection, which may be evidence for neuroinflammation. Overall, no significant differences between SIV+ vs SIV- groups were found for any analytes detected in plasma or CSF during ZIKV infection. Collectively, our results demonstrate that both SIV and ZIKV infections induce a pro-inflammatory response, that is not enhanced by SIV-ZIKV co-infection. This suggests SIV induced immunosuppression does not impair pro-inflammatory cytokine responses during ZIKV infection.