 All right, thank you, Helen. And it's exciting to see so many people here, especially administrators. It's nice to talk about something we're passionate about, in my case, biological imaging, something we do almost every day in the Pagina lab. So this is an example picture of the part of the beauty part, not the most useful image in the world, but this is one of our favorite organisms, a green algae stained with tubulin, and it's quite nice. But since the beginning of humanity, humans have realized that we live in a very beautiful natural environment. And this has interested everybody for a very long time, from artists and naturalist philosophers and the scientists of antiquity. So some people, some of the greatest minds of antiquity, like Aristotle, were classifying animals based on the tools he had, his eyes, and organizing the world into a way that made sense to him. As time progressed, we have people like Galileo that built instruments like the telescope to look at celestial bodies in the sky, all trying to make sense of the world, the natural environment that we live in. So we had these huge celestial bodies in this tiniest of insects all categorized, but does it go smaller until a fairly long time, the mid 17th century? I wasn't really sure, it was unknown what was smaller. Until Robert Hook came along in the middle of the 17th century, and he took a piece of plant and looked at it under a microscope that he had built, which magnified things 277 times more or less. So not much in terms of the power that we have now, but it was the first time that you could see into living organisms. This was an extremely important event because you can draw a direct line from the first visualization of cells back in 1665 by Robert Hook. It's the understanding of the generation of life. Life didn't spontaneously come from dead things. It fundamentally changed the way that people, humanity, thought about life. So using a similar microscope about 260 times magnification, Anton von Luenach looked at a variety of things like pond water and even the crap tiniest teeth under his microscopes. And he characterized these things he called animal molecules, or like molecules and animals, a beautiful combination of the word. So here are some of the illustrations that he, I don't think he made these actually, they're made by somebody else interpreting his drawings. But it's actually the first time single celled organisms like protists or bacteria were ever observed under a microscope. This was extremely important because again you can draw another direct line from the first vision of bacteria to germ theory. And it's not just bad air or bad smells, why we get sick. Which was about 100, 150 years difference between germ theory. So these two things actually seeing cells or seeing bacteria were extremely powerful events that pretty much changed the way we start life science. So I like to think about it as a scientific discovery as being St. Thomas. Like Jesus is the visualizer of the discovery in this case. And we're all doubting Thomas as scientists. We need to see to really believe what is going on. Or to put more simply and more contemporary terms, pics or it didn't happen. Which has really been the mantra of biology for the last 300 years or 400 years. So continuing more recently than Anton von Muenach and Robert Hook. Two of the last Nobel Prizes in chemistry have gone to directly to biological imaging in the last 10 years. So I broadly generalized these into two categories. Kind of the way we think most commonly divided forms of microscopy. Light microscopy using a light source to illuminate your sample and to observe it. And electron microscopy which uses electrons as your visualization source to have samples. You can see from early microscopes something we all had in high school to Nikon storm microscope to the left. These microscopes have really gained in complexity and are now extremely powerful devices that don't even look like microscopes. And if the two people that first started using them, Muenach and Hook saw them. They would not even believe that they were microscopes probably. So talk about these different techniques. I'm going to talk a lot about the little green algae Climitomonas that we use as the model organism in our laboratory. And specifically the flagella. This organelle that we study in the Pagina lab and I've been studying for the last 10 years or so. So it's really the best example that I know how to explain to people. But to get back to the division between light microscopy and electron microscopy. So we're looking at essentially the same sample these flagella with three completely different imaging modalities in this picture. So on the left you have cryo electron microscopy which really gives us like structural features within the sample you're imaging. So you can see these two lines which is called the central pair. Very observable in this cryo electron microscopy image. In the middle you have a light microscopy technique called expansion microscopy which you can see a line running through the middle. So we're looking at the exact same thing in two very different ways. And to the right we even have a different image again looking at the flagella where you're tracking a fluorophore moving over time. So you can actually see movement up and down the flagella. So to go into light microscopy. Light microscopy has its advantages because you can label live cells with color and you don't have to kill them or dehydrate them like you do an electron microscopy. Compared to electron microscopy it's relatively fast and easy. The microscopes are easier to operate not to insult light microscopists in the room. And you can really track specific components within the cell. So an image taken the other day by a talented intern Giovanni Multiti in our lab. You can see again in a human cell this time, a cilia that we're interested that's really localized on top of the nucleus. And we can see all types of stuff around it. You can also track dynamic activities in different cell types and growth. So this is a neural growth cone cell. And you can see actin filaments protruding into the environment looking to where to migrate. And the microtubules labeled by alpha tubulin are kind of protruding into the space and providing a scaffold in a region absent from actin. And of course because we have to talk about cilia in the epenomal cells of a brain, you can see a beautiful cilia forest decorated with a microtubule modifying protein or modifying modification in red at the base here. So it works. Light microscopy is super easy to use fast and you can track individual components, look at small things as well as bigger things. So on the scale of organoids, in an organoid picture Flaminia took, this scale is much, much bigger than what we're looking at prior. So we're looking at this one cell level here. Now you see multiple things and you can really plot the divisions, the organizational divisions in this case of mouse hepatocyte organoid. So light microscopy is super useful for the reasons I just described. But if you want to go smaller, which is so important in science today, you need to use an electron microscope due to the principle of the electron wavelength being much smaller than light. So you can imagine or, yeah, optical light. So obviously it's extremely relevant to see things smaller than bacteria, for example viruses or the proteins within a cell, and you have to go to an electron microscope. So an electron microscopy, you can again take images of cells. They have massive atlases now for cutting edge places such as genuina farms, where you have cell types that you can select. We're looking at one cell in two different views. So this is like a top view and this is the view from the side. You can see nuclear organization in mitochondria, basically everything lining around the cell, the complete detail of the cell. And if you zoom in further, this is a layer. Again, you can see multiple mitochondria or nuclei in mitochondria, the organization of a cell layer everywhere. And if you would zoom in on a little area, like I don't remember where this was taken from somewhere over here, you can even see structural features of something that's like 200 nanometers long, which would appear as a dot in traditional light microscopy. So again, going back to our favorite organism, clammy, to highlight the differences in resolution between light microscopy and electron microscopy. If we rapidly plunge-freeze our sample or our cell in very cold liquid, everything is completely natively frozen. It's like what rich people in the United States do when they want to live forever. You put yourself in a cryo and bombing and then you can come out in a thousand years and be woken up. It's the same thing with when you plunge-freeze a cell or a sample into liquid ethane. So if we zoom in on this region here, which would not be possible with conventional light microscopy, we can zoom in 42,000 times and see this picture of the base of the central, or the base of the flagella, which you see just by one little dot in this light microscopy picture. Then if you take many images of one thing and combine them in the orientations and do some computational processing, not to insult the computational people here, which is also a huge element in any microscopy now, you can put together these beautiful models and really help you understand what you're looking at. So by averaging here, you can see nine little rings, which gives you insights onto how these nine microtubule doublets are formed. These appendages look like arms that are useful to grab things. So seeing very much is believing in this context, that any time you can directly observe something at this level of detail, it helps you interpret what its biological function might be. So you can combine these image modalities if we go back to the basal body and we see these global structural elements as we saw here. You can see the skeleton of the basal body, the base of the flagella, and you can see little things hanging off of the side. If you combine this with light microscopy on two approaches, which is super good at identifying which proteins are where, you can get an image where you understand the protein composition of these structures. So in pink here we have tubulin, which we know is the cytoskeletal component and kind of a reference map compared to our electron microscopy. In green we have a protein that is forming these little lines, which are kind of hard to see in an untrained dive, but trust me there's a little stringy train there. So we can start to map protein composition to structures, global structures we see in light microscopy. So in summery now, I'm sorry, the lack of not giving, it's a very, very deep subject, and I didn't even get into things like single particle electron microscopy, where rather than looking at global massive structures like this, you look at even proteins and see what they're binding to and what they're touching, or more simpler tissue light microscopy. But at least the images were very nice and I hope to convince you that imaging, there's an aesthetic beautiful aspect to performing microscopy as well as a highly functional thing that allows us to really process in our minds what we're seeing with what its biological function might be. So thank you, I'm finished.