With recent advances in wearable technologies, there is a growing demand for high power density batteries with more complex geometries. However, conventional battery manufacturing processes such as blade casting are incapable of producing the desired complex form factors. As an alternative manufacturing method, researchers are using additive manufacturing (AM), which allows for the rapid and efficient production of complexly shaped lithium-ion batteries (LIBs). A commonly used type of AM is direct-ink write (DIW) printing, a manufacturing technique where material is extruded through a syringe using displacement-controlled mechanisms. However, DIW typically lags from when pressure is applied to the syringe to when the battery material gets dispensed onto the surface. This lag can result in the printing of inaccurate features that negatively impact battery performance or even cause device failure. To account for this lag, we created a software module using the programming language C#, allowing users to print with micron-level precision. The module was integrated into the Rhino and Grasshopper platforms, a commercial computer-aided design (CAD) software package, enabling direct application into CAD models. The module can accept a list of curves as an input and will output a transformed list of curves that are more accurate to the CAD design. This module eases the challenge of printing material at the micron level, however, further research must be conducted to implement this module into lithium-ion batteries AM.

Soft electronics are small, flexible devices that have potential in next-generation applications such as wearable electronics, robotics and biomedical devices. Additive manufacturing (AM) has been demonstrated for fabrication of electronic circuitry and insulation, but some electronic components cannot currently be made with AM. These components are typically placed onto devices by hand. We aim to develop an AM process that uses a single motion platform to switch between printing circuitry and placing electrical components without the need for manual intervention. In the pursuit of full automation, we designed and built a pick and place (PnP) tool that is compatible with the Jubilee open-source 3D printing platform, and developed software to create integrated toolpaths. The Jubilee is the ideal platform for testing multi-material 3D printing in conjunction with PnP because of its ability to switch between tool heads mid-print. Our workflow for AM of soft electronics includes 3D printing of electrical circuitry via a material extruder tool, part placement with the PnP tool, and automated switching between the tools. We have programmed software that takes user input of starting and ending component location and creates machine code. The machine code tells the Jubilee where to go and when to activate or deactivate the vacuum system. We validate the functionality of our PnP tool and software by placing components in designed patterns. We then incorporate our PnP tools into the AM process to demonstrate fully automated fabrication of a simple circuit design. Integration of our PnP tool into the Jubilee open-source platform enables circuit printing and part mounting to be executed without manual intervention and is a step towards complete automation of AM for soft electronics.
 

Hypoxic-Ischemic Encephalopathy (HIE) resulting from a lack of blood and oxygen to the brain is the leading cause of mortality in term newborns. Extracellular vesicles (EVs) serve as critical transporters of biomolecules between cells, with evidence of alleviating inflammation in models after hypoxic ischemia (HI) injury. Therapeutic efficacy of EVs has only been evaluated in males because males are more susceptible to worse outcomes following HIE injury, yet knowledge about EVs and their behavior when administered to females is still needed. In this study, I aimed to address this knowledge gap by systematically comparing the efficacy of male and female neonatal brain-derived EVs (mEVs, fEVs, respectively) applied on male and female neonatal rat ex vivo brain slices. I first confirmed the purity of isolated EVs with protein assays and immunoblots, and utilized an ex vivo oxygen-glucose deprivation (OGD) model of HI injury, applying fEVs and mEVs to sex-matched OGD-exposed brain slices. I evaluated cell viability after 24h of EV exposure, and my results show that fEVs decrease inflammation and cytotoxicity in OGD models. When compared to previous results using mEV treatment, my results suggest that females have a more robust anti-inflammatory response system to injury. Ongoing work to better understand the therapeutic effect of EVs involves further observing morphological shifts in microglia through confocal imaging, as fEV application will likely result in microglia shifting towards anti-inflammatory phenotypes, similar to what was previously observed after mEV application. I am also quantifying expression levels of various inflammatory and reparative genes through reverse transcription quantitative polymerase chain reactions (RT-qPCR). Overall, I have demonstrated in these pilot studies that fEVs have a different therapeutic effect in OGD injury compared to mEVs. This research is intended to open up pathways for more personalized sex-based treatments for various injuries and therapeutics in the future. 

Quantum dots are nanometer scale semiconductor particles that have been extensively studied over the past decade. Colloidal quantum dots are dispersed in solution, and so can be easily deposited on a surface. This allows them to act as highly versatile quantum sensors. I am studying cadmium selenide quantum dots doped with manganese (Mn:CdSe). They possess a spin of 5/2, meaning they have six spin states, each corresponding to a different quantized energy. These six energies can be probed with photoluminescence spectroscopy, and theoretically appear as six distinct peaks in the spectrum. This allows us to use spectral analysis to read the spin state of a dot. Due to the Zeeman effect, the spin state energies are sensitive to applied magnetic fields. A simple sensing procedure first initializes the spin state, allows it to evolve under some magnetic field, and reads out the final spin state. My work focuses on the initialization and readout of the spin. For this purpose, I previously built a monochromator to characterize the quantum dots under pulsed excitation at various wavelengths, power, and temperature. I am measuring their properties using photon counting correlation measurements, photoluminescence spectra, and lifetime measurements. The goal of these results is to characterize the properties of these Mn:CdSe quantum dots to lay the groundwork for their development as a highly sensitive quantum sensor.

Half of the earth's photosynthetic activity occurs in the ocean. However, marine ecosystems generally have lower rates of carbon sequestration when compared to terrestrial ones. This is an opportunity to enable large scale carbon sequestration. The waters of the open ocean are nutrient deficient and can have low primary productivity. Supplying the limiting nutrients can theoretically enable rapid growth of photosynthetic cells but this growth must be contained or it will be lost to the ocean. By preparing these missing nutrients in hydrogels with efficient photosynthetic consortia, the growth process and inputs can be contained and the biomass harvested. The Winkler Lab is using this method to develope biological systems for carbon sequestration. I am researching the efficiency of microalgae and cyanobacteria consortia in seawater with native microbes. I aim to form cultures of photosynthetic marine microbes by inoculating hydrogels containing chlorella sp. in seawater samples. The objective is to optimize squestration with naturally occurring microbial consortia. Through multiple trials I have identified a mix of microbes and macroalgae cultured from the Puget Sound that exhibits rapid biomass production. Data is collected via microscopy, imaging and by measuring chemical oxygen demand and chlorophyll content. My aim is to compare this wild microbial mix to the Winkler lab's established mixes of cyanobacteria and microalgae and determine which is more effective in fixing carbon. Expected results will demonstrate this wild culture more efficient in low nutrient environments than the lab culture. Success in this project could help refine commercializable methods to remove atmospheric carbon dioxide and fight climate change.