 it's not just viruses that have a usage of understanding fusion of membranes. Do you remember what this was? This was the RNA sequence of the Pfizer-BioNTech vaccine against COVID-19, which was an mRNA vaccine, which is a new technology where instead of just injecting directly injecting components of proteins and getting the immune system to recognize them, we're injecting RNA to instruct the cells to produce the protein. There are a couple of advantages. One of them is that we don't have to grow viruses in eggs and produce the proteins, but it's also that ideally we can target things in a more efficient manner. There is only one problem. You need to get this mRNA into the cells where they should start producing the protein, otherwise everything is lost. You can't just inject mRNA directly because it's going to break down fairly quickly, even if your immune system doesn't attack it. So we're going to need some sort of delivery vehicle and delivery mechanism, and by far the most efficient state-of-the-art way of delivering mRNA is to use lipid nanoparticles. This is just a sketch. We don't know exactly what lipid nanoparticles look like. So it's a mixture of lipids. We have mostly lipids. A few other, a few different types of lipids in many cases. Maybe a bit of cholesterol to make it stiff. Inside this there is kind of a lake. So we have these small bubbles where we have the mRNA and there's going to be some water, but again we don't know exactly what the internal structure of these are. You also have some lipids or in a few cases maybe amino acids that are charged. And the reason for that is that we have different pH environments in different parts of the bodies and cells. And we would like to have a delivery vehicle that keeps things inside this lipid nanoparticles until we get to the place where we want it to be delivered and then it should change structure and magically release the mRNA in the right place. And it turns out that the endosomal membrane in particular where we want to deliver this is related to a change in pH. But exactly what they look like inside, we have no idea. There has been a lot of experiments trying to improve the efficiency of this, but this far it's mostly based on experiments that some things work better and other things don't work. There have been a handful of simulations, primarily coarse grain ones where we try to make sense of this, but this is very much a widespread on the map. We don't really know the molecular mechanisms of lipid nanoparticles, how they deliver the mRNA inside the endosomal membrane. And this is going to be a remarkably important field of research the next few years given the success of mRNA vaccines, I think. But that's going to be research you have to do.