Drum roll, please …
- Eggs are healthy: Eggs are nature’s perfect food, providing excellent protein, as well as the gamut of nutrients and important fatty acids that contribute to the health of the brain and nervous system. Americans had less heart disease when they ate more eggs. Egg substitutes cause rapid death in test animals. Chirs Masterjohn, PhD, teaches us about the Incredibly, Edible Egg.
- Butter is good for you: Butter contains many nutrients vital to growth and brain function. Butter has nourished healthy populations throughout the globe for thousands of years. Read more about why Butter is Better from the Weston A. Price Foundation.
- Saturated fats and cholesterol are vital for optimum health: Cholesterol helps babies and children develop a healthy brain and nervous system. Saturated fats provide integrity to the cell wall, promote the body’s use of essential fatty acids, enhance the immune system…
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Hi everyone, and a very happy new year. May you always be as productive as you plan to be.
Talking of which, I want to start of this year with a little rant. Or is it actualyl a rant? I’m not sure. All I know is that I’m still sitting in the lab on satruday, after a more than just laborative week, having a pretty serious cough on top of things. And why am I doing this? not even so that my own research would thrive. Nooo way! I’m teaching at the moment. – full time – The question is does it really bother me that I’m still in the lab on a saturday, despite this being the first day of real snow around here this winter? Or do those endless hours in the lab the last week bother me?
Not really. Becaus I’m doing something I actually really enjoy. You could even say love.
Teaching students, at the end of their masters program, bright and curious minds. Who spend almost as much time here as I do. I know a lot of people that don’t quite enjoy teaching as much as I do. But for me, that spark of understanding in their faces, that neverending question in their eyes; sometimes asking for which buffer to use, sometimes complete not-understanding what is going on at all, and sometimes really elaborate scientific questions demonstrating deep understanding of what actually is going on. Those questions, and the moment they find their own answers (with help at times) is really building up my own self confidence and I enjoy it, a lot! And it is one of the most important things in science if you dare to ask me. Of course, I’m kind of educating, almost breeding, my own competitors for the future (maybe even my own bosses). But what worth is knowledge, if you don’t pass it on?
I once heard someone saying about science and education, it’s not about passing on the torch, it’s about lighting the spark. And I don’t really agree. It’s about both, it’s teaching how to light a fire, and giving away tons of wood to burn!
Same thing goes for creativitiy if you ask me. Creativity, in a way, is synthesising all the things one knows and knows how to do, without being aware that that is what one is doing. And the combination of all those old things, with just a little new idea. That is what creativity is.
In the end, you cannot be a great singer songwriter on the guitar, if you don’t know how to play a guitar.
So, I guess what I want to say is, if you enjoy teaching, then do it, if you enjoy learning, just do it! And maybe you realize that both go along hand in hand. I’m learning the most when I’m teaching myself. Because I have to look at things from another point of view, my students point of view to be more precise.
I think we could all do that a little more often, and I think it is one of my good intents for the upcoming year. Try to actively look at the things I do (or everything for that matter) from more than only my own perspective.
Makes me curios actually, what would be your new years resolutions?
I’m back, somehow, and enthusiastic to get back talking about the principals of microscopes (and for that matter other related optical devices too).
In my last post on microscopy I was talking about the focal length, which applies equally well to cameras, binoculars and microscopes. Numerical aperture applies to the first two too, at least to some degree but it is far more important for optical microscopes and can be pretty much ignored for macroscopic devices. The reason for that is that binoculars and cameras, as well as stereo microscopes typically operate in air, which by definition has an light scattering index of 1.
Okay and there we are deep inside the topic already, without even noticing.
What does 1 mean? In this context it means the way that light is bend/refracted when it moves from one medium to another. In that sense numerical aperture pais tribute to light passing from the air where it travels at maximum speed, into another medium where it will travel at a different speed, and thus change direction. Okay, I give you that, light does not change speed, however in every medium (which excludes vaccum as a no-medium) light will express its dual character as a particle and a wave in that matter that it will go on a straight line until it gets influenced by the forces of atoms it passes through/by. This will change the direction of the light. Its a bit like playing on one of those old fashioned flipper-machines. If light has to pass through a dense medium it will have many encounters and frequently change direction. This in trun means that the distance the light travels will become longer and thus it will take longer to pass through. That means a lightbeam that travels in a straight line through 1cm of vacuum will take an amount of time defined by light speed, (which is a ridicolous short amount of time) we will define this time as one to ease things up that means. If we now replace this 1cm of vacuum by normal air, the lightbeam, or photons, will have a certain number of encounters that correlate to the number of atoms in a gas under a given temperature and pressure, which one could express with the universal gas-equation. So, 1 cm of air seen from the outside becomes something like 1.5 or whatever cm of actual distance the light will have to actually travel, and thus will take a longer time to reach the other end. The more dense our medium gets, the more encounters and the higher this refractive index, and the distance the light has to travel, which from the outside appears as if the light would slow down.
So much for that idea.
Now glass as you would find it in a normal lense would have a refracitve index, or numerical aperture, of 1.52 (Remember air has 1) That means if you enlighten your sample on your glass slide, that that light typicially will have to travel through glass, your sample, the cover slip (glass again), air, glass again. with light being bend towards the more dense medium that would mean you will get light scattering at the interface between your cover slip and the air and that means you technically lose light you would like to have collected in your lense. So what you would do is add oil having the same refractive index as glass (1.52) between your sample and the lense and by this the pathway of your light gets altered only once. Namely, when its passing through your sample, which is exactly what you want because that is where your image gets created.
Check out the site I linked below, the have some nice explanations and images on that topic too.
I cannot possibly not share this.
This guy has such an amazing voice, I still sit here trying to believe it. I’m pretty sure it’s real, but still I’m having a hard time believing it. It’s just, my eyes and ears don’t agree that this could be possible. Just have a look. And yes the human voice is probably the most impressive music instrument known to humans!