Symmetry is a major trait in the architecture of the vast majority of animals: if we exclude sponges, a typical animal body plan will show one or more planes of symmetry. Radial symmetry is considered the ancestral state for the Eumetazoa, with body plans such as the polyps and jellyfishes within the Cnidarians, usually with […]
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PET helps ID tau protein in the brain PET shows promise in detecting tau protein accumulation in the brain, according to a study in the journal Neuron. Researchers developed a chemical that binds with the substance and used PET to identify areas of the brain at risk of neuronal death. The approach was evaluated in […]
Last February I was giving a 101 Astronomy class early in the morning. It was Friday, the 15th. Just by chance, I was talking about the minor bodies of the Solar System when we started speaking about impacts on Earth. I showed some slides of the Tunguska event and how the devastated area was similar […]
Animals like spiders, snakes, scorpions, and cone snails inject venoms to their preys to immobilize or kill them. But what there is in these venoms that can trigger such a strong effect? The venom of these animals is actually a cocktail of toxins, from which one of the main components are peptides. Due to their […]
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Reprogrammed stem cells in mice could pave way to tissue regeneration Spanish scientists successfully forced mature cells into an embryonic-like state inside the bodies of living mice, creating so-called reprogrammed induced pluripotent stem cells. Transforming mature cells into stem-like cells “means turning back the clock when everything in the environment favors the opposite,” lead author […]
We saw at the end of the first entry of this series that, in spite of the adjective ‘true’ seeming to be semantically redundant in the sense of its role being equivalent to just assert exactly the same assertion to which it is applied, it is nevertheless grammatically non-redundant, in the sense that there are […]
The relevance of demand factors for explaining growth was stated almost simultaneously by Michal Kalecki and John Maynard Keynes in the 1930s. The main conclusion of the theory of effective demand is that spending determines income. Keynes stated that the marginal propensity to consume decreases when total income growths. Kalecki considered different propensities to consume […]
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Hypersonic flight to undergo further study The U.S. Air Force and the Defense Advanced Research Project Agency are joining forces to study the capabilities of hypersonic flight. The project will build on the Air Force’s X-51A Waverider program, which ended in May when the unmanned craft reached a top speed of Mach 5.1 riding on […]
Quantum mechanics and relativity constitute the two main revolutions in physics on the twentieth century. Furthermore, the counterintuitive character of quantum mechanics yields to a rich branch of different possible interpretations, and there are still many open questions. Not solving, but just defining these questions, was the main purpose of a conference entitled “Quantum physics […]
The greenhouse effect is possibly one of the scientific topics most frequently covered by the mass media. When reading the news, it is very often difficult to separate ideology from the purely scientific content. However, the greenhouse effect has a profound and direct impact on the planet where we live and, also, in other potentially […]