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 […]
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Long canyon lies beneath Greenland Ice Sheet A canyon nearly twice as long as the Grand Canyon has been found under the massive Greenland Ice Sheet. By studying data compiled over three decades, Jonathan Bamber of the University of Bristol in the U.K. and his team discovered details about the canyon, which is at least […]
It was commonly assumed that no new neurons are formed in the adult mammalian brain, even after the first results showing neurogenesis in rodents were published in the 1960s. Further work in mammals and birds during the 80s contributed to change the scientific consensus, but it was the discovery of adult neurogenesis in humans in […]
Disclaimer: What I will relate in this post is the result of my research during the last year and specially the results of my last paper, uploaded as a preprint to ArXiv.org with reference arXiv:1307.2060 . Apart from the self-promotion, I think this is interesting since it can give people an insight on how short […]
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BMI may not be accurate predictor of fitness, study suggests Metabolism and body mass index do not go hand-in-hand, according to a study published in the journal Science. According to the study, it is possible to have a normal-range BMI while also having an abnormal metabolism, indicating that it’s not prudent to rely on BMI […]
Classic rail vehicles have rigid wheelsets: both wheels are interlocked and have the same degrees of freedom (DoF), so they share all their displacements. They also have positive conicity, this is, the wheel surface on the contact patch is conical and, if we extend these ideal cones, their base would meet at the centre of […]
Until the 70’s of the last century there was a great divide in Economics. On the one hand, Microeconomics studied the individual economic behavior, whether of a firm or a consumer, and was able to construct a General Equilibrium Theory that explained remarkably well (at least, for a social science) many economic regularities like market […]