But

you can say that, well, there's a big peak here, so what about this peak? But if you notice that the vertical axis is also logarithmic, so the concentration here of these large particles in this large mode is insignificant compared to these small particles.

Where do they come from? The first small mode comes from bronchial fluid field burst when we inhaled and exhaled a blockage occur and then during the next inhalation they break and that's how aerosol is generated.

Interestingly, this has been linked to generation of this particular pathogen, H5N1, which is thought to be located in this part of the respiratory tract.

This is a very important aspect.

The particles are aerosolized from the different parts of the respiratory tract, but if there's something else in addition to the normal constituents of the respiratory fluids, it will be aerosolized as well, and in particular viruses or bacteria.

The second mode is laryngeal vibration mode, slightly bigger.

particles during breathing.

did your childhood dream.

Yeah, that's right.

Yeah.

Oh, and most people don't.

That's incredible.

It was nuclear physics.

But after my undergraduate degree, I started developing an interest in something still related to radioactivity, but a bit different, environmental radioactivity.

Do you want to share a little bit more about what that was, what's that informing, and then, yeah, what action people can take from that?

By the time you landed, you had to do something about it kind of thing.

So what happened in that situation? So, of course, the pandemic started evolving and we saw, I saw, we saw the information being provided completely wrong.

I remember once around Brisbane driving and a big sign over the road, wash hands save lives.

going to the supermarket, supermarkets, and then seeing people with gloves, no masks.

And everything which public health authority was saying was wrong.

So that was...

And then I was and we were trying to work on this in Australia, but...

So I think a bit like TVOCs, I think we've got a little bit of a way to go with PMs, but they're pretty good, right? Not bad.