The enigma of twins

The behavior of the four Genain twin sisters, born in the U.S. in 1930, drew the attention of psychiatrists at the time.
As a child, Hester broke light bulbs and was booted ios buttons; Nora gems during meals and put on their knees and elbows to bleed, with 22 years, Iris stopped working because he felt "trapped"; Myra was better, but are easily frightened and reassure her hard work.

The four were diagnosed with schizophrenia, which seemed to prove the importance of genetic factors, since the probability that the disorder affects four people chosen at random is 1 in 100 million.

Moreover, the degree of gravity was different in each one, which indicated the presence of other factors, but what?

The psychologist David Ro-senthal explained the differences in degree from family relationships, as Myra, the less sick, was the favorite of the mother, and Hester, the most serious, since girl was labeled as "bad".

For his part, the neuropsychologist Alian F. Mirsky discovered that the twins through tomography most affected also showed more abnormalities in their brain activity and that their frontal lobes, which act as a focal point for information, were weaker and less energy consuming than those of their sisters.

According Mirsky, Genain suffered varying degrees of injuries due to the order of their birth. Nora could suffer trauma as the first to pass through the uterus and Hester, most recently, by lack of oxygen.

The brain scanner in a recent case of twins, Elmore, proved that the ventricles of Steven, schizophrenic, had thicker tissue and neuro-nal thinner than the mentally healthy David.

The anomaly of water: ice

Unlike the vast majority of substances, ice floats in water liquids. That's because this is no more dense when you're at 0 ° C, but at 4 ° C. If not, there would be no icebergs or resale pipes to get frost. In addition, rivers and lakes begin to freeze the fund to the surface-and we could not skate on them.

It is not the only peculiarity of ice. In fact, there are 14 different varieties, something equally special because solids usually show two or three different types of crystalline structures.

The fact that we all know has a hexagonal structure and is called Ice Ih, but playing with the pressure and temperature can generate other structures.
In nature we also find ice or cubic lc, which is formed from water vapor at normal atmospheric pressure, but at temperatures below 80 ° C below zero. This kind of ice may form in the upper atmosphere.

In 1900, physicist Gus-tav Tammann discovered that the ice if subjected to 3,500 atmospheres-three and a half times the pressure that exists at the bottom of the Mariana Trench-appeared two new states: ice II and III.
A decade later, Percy Bridgman, from Harvard University, identified 5 more varieties. Among them, ice VI was known as "hot ice" since remained without melted to 80 C, provided that they exercise over the 6,500 atmospheres.

Of these, the most ghostly is the ice IV, whose structure was not discovered until 1981, 44 years after being detected, because it becomes very quickly into a more stable, V. And the race continues in 2006, Science magazine reported obtaining ice XIV.

In the solitude of the only space we have found that ice is amorphous. How do you get it? Well, ice cream artisans hold the key: cool very quickly to prevent crystals from forming.