School quitter invents electrical system

Nikola Tesla was an inventor whose discoveries were important for the commercial use of electricity. He studied electrical engineering at the Austrian Polytechnic in 1875, but never completed his courses. In 1884 the young inventor became an assistant of Thomas Edison and developed an AC electrical system which he sold to Edison's rival due to a lack of interest of Edison himself. Thereafter, Edison and his rival Westinghouse got in conflict with each other, each one believing in their own systems. After this incident, Tesla continued his expensive experiments, such as his experiments on a death ray, and due to his persistency, he died impoverished by his debts at the age of 86. After his death, the tesla unit was named after him as a recognition of the importance of his work for the commercial use of electricity.

Grubby science

Parents always tell their kids that it is very important to keep their rooms tidy and clean. But dirt isn’t always a bad thing, just look at the example of Alexander Fleming, the discoverer of penicillin, an antibiotic. This famous scientist left his lab to celebrate his holidays, leaving on his desk a mess of notes, perished foods and… an open petri plate covered with bacterial colonies.

While Fleming was enjoying his trip, a little mold, called Penicillium, got the chance to develop on his desk and began to grow on the petri dish, accompanying the bacteria. When the lucky man came back from his holidays, he looked at his plate and observed that most of his cultivated bacteria had disappeared. This was the moment when Alexander Fleming concluded that the mold produced an antibiotic and so the penicillin was born.

Can dinosaurs be brought back to life?

Almost everybody has seen the movie Jurassic Park and probably nobody thinks that the extinct dinosaurs can actually be brought back to life, but that’s not so sure.

Another extinct species, the Iberian ibex, has revived in 2009 by cloning frozen tissue, collected from the last living specimen. By fusing cells of the frozen tissue with oocytes from goats, an embryo arose, which was implanted in a domesticated goat.

If an extinct species, like the Iberian ibex, can be brought to life, it could also be possible with dinosaurs. For this you need soft tissues of a dinosaur with an intact genome, which were recently found in a femur of a Tyrannosaurus Rex.

So who knows, in the future there could be dinosaurs walking on earth again.

Antimatter: our ticket to Mars?

Antimatter is one of those difficult subjects particle physicists are dealing with these days, but to put it shortly, antimatter is the counterpart of matter. Matter consists of particles, whereas antimatter consists of antiparticles, for example an electron is the counterpart of an anti-electron or a positron (an electron with a positive charge). Mixing matter and antimatter leads to the annihilation of both and so does mixing particles and antiparticles, but it also leads to the formation of high-energy photons (gamma rays) or other particle-antiparticle pairs. These high-energy photons created by the collision of matter and antimatter have a much higher kinetic energy output than today’s fission plants, the collision of 1kg of matter and 1kg of antimatter would produce 10.000 times the amount of energy produced by nuclear fission. About 50% of this kinetic energy could be used, the other 50% would be lost under a form of particles and antiparticles that travel at the speed of light and have no mass. Particle physicists are looking for a way to create antimatter and harness the energy from a collision with matter in redshift rockets for example (these allow for interplanetary or even interstellar travel), so maybe humanity can explore outer space in the (not so distant) future and even colonize Mars.

Female dragons are hot!

Unlike mammals, where the gender is determined by X and Y chromosomes, reptiles use a variety of strategies to determine the gender (with the X/Y system being just one of them). Some species of reptiles use Z and W chromosomes (similar to the X and Y chromosomes of mammals), where the female is the one with the different chromosomes (ZW) and the male the one with the same chromosomes (ZZ). More extreme are the species that don’t even have sex chromosomes, but where it’s the temperature that their eggs were incubated at that determines the sex of the hatchlings. Scientists had long believed that every species only uses one of these strategies, until they discovered that the central bearded dragon (picture) uses both these methods to determine the sex of individuals. Only when its eggs are incubated between 20 and 32 degrees Celsius, the Z/W sex genes determine whether the hatchlings are male (ZZ) or female (ZW), but when the eggs are incubated at higher temperatures, the sex chromosomes are ignored and all of the hatchlings are females, even if they are genetically male! With the temperature rising due to global warming, we can only hope that these reptiles aren’t all born as females, or the extinction of these amazing creatures will be inevitable…

Black Beauty

Penguins keep surprising us, as this all-black King Penguin on the left shows. The remarkable animal was spotted in Fortuna Bay, South Georgia, waddling around with his dull, white-chested King Penguin friends. In contrast to his friends, the all-black King Penguin is –what a surprise- completely black due to an increased melanin level in his body, a disorder also called melanism. Melanism quite often occurs in certain animals, like in squirrels, but in penguins it is extremely rare and biologists believe less than one in a million penguins show this unique feature. The black beauty probably got a mutation in one of the genes responsible for the control of pigmentation, but besides that our striking friend is completely healthy. Who thought they had seen everything with gay penguins, think again.

How to create siamese twins?

In 1924 some of the most interesting and important experiments in developmental biology were preformed by the German embryologist Hans Spemann and his PhD student Hilde Mangold . For these experiments they isolated some tissue from different parts of early embryos of salamanders and transplanted it to different locations in similar embryos . When they transplanted this special part of tissue, the dorsal lip of the blastopore to the ventral side of an other embryo, the most extraordinary thing happened… As the embryo developed they saw that not only at the original dorsal lip of the blastopore, but also at the transplanted one, gastrulation occurred and a complete embryo was formed . Closer research pointed out that this dorsal lip of the blastopore plays a very important role in the inductive processes that occur during embryonic development . Therefor this interesting region is nowadays called the Spemann organizer .