Hi, my name is Yolande and my project is focused on printed biomedical tattoos used for electrophysiological signal acquisition and I've been a student at York for around two years now. When it comes to acquiring signals from the body based on research, the best way to kind of gather these signals is to form or use the kind of sensor that completely fits seamlessly with the body rather than sitting like directly rigidly on top of the skin. The idea of these medical tattoos is that they kind of conform to the skin, they move with the body, they're more comfortable for the user. The tattoo paper itself, it has a layer of starch on top and this allows for a pattern to be printed and then transferred onto the resulting surface, which is the skin. When I initially started this project, I saw that a lot of the tattoos that were being developed in academia tended to be kind of just the same standard shape and I thought, okay, I have this printer, I can make different types of shapes. I can make squares, I can make circles, I can even make serpentine kind of structures which are proposed to kind of be more mechanically robust. I would print out these different shapes, I would test them out, I would see in terms of the performance, if there would be a difference in terms of the signal quality. Once you know how to use Eagle, you can print pretty much any design. In terms of the printing process that I would follow for developing the tattoos, initially I have my substrate, which in this case is the tattoo paper, I have that prepared cut out. From there, it's like I literally just follow the steps in the NOVA program, so I have it ready, I do some probing on the surface to make sure my pattern is properly laid out, do the calibration with the cartridge itself to make sure my lines come out well. Lastly, I just print on the surface, check, you know, there's a camera in the program to see how the pattern actually came out and then once everything is good, I can just take it off, cure it on a hot plate and then go from there. So the signals that are acquired with the tattoo paper, they can range from electrocardiogram signals or ECG, which look at the electrical activity of the heart, also EMG, and they look at the electrical activity of skeletal muscles, but they can also potentially be used to acquire EEG signals or electroencephalogram. Those look at the activity in the brain. There is a use case for everything. In the case of the conventional tattoos that are used in like clinical settings, you know, if you're just going to go get an ECG done and, you know, it's going to be like a very temporary situation, maybe those are suitable. In the case of the medical tattoos, if you are in a situation where you have to get repeated measurements. Also, in the case of kind of the structure of the tattoo, because it's quite thin, it can potentially be used for like functional purposes, like maybe integration with prosthetics, that signal is taken in and that it's used to form or kind of used to like move something in the process. This is kind of a almost like a starting point, like once the kind of printing parameters for, you know, printing the specific ink on the specific substrate, once those are kind of optimized, you can go further, you can work on different sensors that can be integrated with the body, such as strain sensors or even potentially explore areas of energy harvesting. With Nova, I, it kind of makes the printing process a lot more efficient. So I'm able to easily calibrate the materials that I'm using and then just print immediately. And it also helps to kind of specifically align the patterns that I have onto a substrate. So overall, it just has helped kind of make the process more efficient and easier to change. And it has significantly reduced the amount of time that it actually takes to print the resulting pattern on the substrate, you know, compared to more traditional processes. It would involve like the use of a mask or the use of like kind of laser cutting and that requires more time and it requires significantly more expensive equipment. It's very, very user friendly. You can, you know, you don't have to be honestly an expert once you kind of get the basics regarding, you know, how the setup should be and how things should be laid out and how to use the program, you're good to go. So I, you know, wrapped up my research with this project on these printed medical tattoos, but if I can keep using Nova, I will gladly use it.