Diffusion and Osmosis (via Khan Academy).

Osmosis Computer Simulation: "This is a shot from a three dimensional computer simulation of the process of osmosis. The blue mesh is impermeable to the larger balls, whereas all of the balls are (in the animated version) bouncing about according to the rules of physical simulation of the kinetics of an ideal gas."

Osmosis Computer Simulation: “This is a shot from a three dimensional computer simulation of the process of osmosis. The blue mesh is impermeable to the larger balls, whereas all of the balls are (in the animated version) bouncing about according to the rules of physical simulation of the kinetics of an ideal gas.”–Via Wikipedia. 

“There is more evidence to prove that saltness [of the sea] is due to the admixture of some substance, besides that which we have adduced. Make a vessel of wax and put it in the sea, fastening its mouth in such a way as to prevent any water getting in. Then the water that percolates through the wax sides of the vessel is sweet, the earthy stuff, the admixture of which makes the water salt, being separated off as it were by a filter.”

[This is an example of Aristotle giving proof by experiment, in this case, of desalination by osmosis.]

Even 2,000 years after Aristotle’s rough experiment, scientists, students, and teachers still have something to say about this phenomenon; which “plays a role in the blood circulation, keeping just the right balance between the water content of the blood and the surrounding tissues. Osmosis drives fluid flow in the kidneys, preventing waste products from accumulating to dangerous levels. Osmosis is also the driving force behind plant cell expansion, playing a role in flower and fruit growth.” (Via Scientific American, May 1, 2013).

The following video from Khan Academy illustrates what Aristotle observed. It also provided explanations through the use of experimental models:

PBS Documentary on Animal Reproduction: Why Sex?

Peacock

The colorful feathers of peacocks have inspired a lot of art, science, and even frustration. Charles Darwin had a notorious hate for peacocks; their feathers made no sense to him. Nowadays we have more insight on this evolutionary issue.

“We may conclude that…those males which are best able by their various charms to please or excite the female, are under ordinary circumstances accepted. If this be admitted, there is not much difficulty in understanding how male birds have gradually acquired their ornamental characters. In all ordinary cases, the male is so eager that he will accept any female, and does not, as far as we can judge, prefer one to the other.” — Charles Darwin

The following video–of about one hour of duration–begins with a very poignant explanation of the advantages of peacock feathers:

The i-Limb Ultra Revolution: an app controlled bionic hand.

"I have been able to hold my daughter's hand for the first time in five years since my accident." -- Jason Koger

“I have been able to hold my daughter’s hand for the first time in five years since my accident.” — Jason Koger

Do you need a bionic hand capable of using opposable thumbs; of picking up small things, and of doing a handshake?

There’s an app for that.

Livingston based (UK) Touch Bionics developed a prosthetic hand capable of doing 24 different types of grip patterns. And double amputee, Jason Koger, has become the first person in the world to get a pair of bionic hands that can be controlled by an iPhone app:

 

You can read more about this breakthrough here.

Beautifully creepy, 3D printed synthetic tissue.

No es una gastrula. This is synthetic.

No es una gastrula. This is synthetic.

A custom-built programmable 3D printer can create materials with several of the properties of living tissues, Oxford University scientists have demonstrated”. — Via 3D printer can build synthetic tissues 

The following 8 second video shows this lifeless object behaving like a lotus flower–with yellow and blue hues: