Study Into Sleep Type Inhibiting School Achievement

A chronotype is an interesting thing. Much like the phenotype is the the outward expression of a persons genetics the chronotype is the outwards expression of a persons circadian rhythm. The extremes of the chronotypal scale are eveningness, where people demonstrate peak awareness in the evening and morningness where they are most alert in the morning. Normally people are not at these extremes and have sleep cycles that lead to them having an optimal time which is some time in the middle.

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Organising Graphene To Self Ordered Arrangement

The manipulation and fabrication of structures on a nanoscale is no small feat. The idea that we are able to control events happening on the scale of atoms is incredible and when it comes to technology there is very little more futuristic than circuit boards made out of just  a few atoms. Normally the nanostructure such as the quantum dot or the metamaterial has to be infused into a solid matrix to support it. One common effect that arises is that of misfit stress as represented by the diagram below:

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Tracking Dolphins By Their Din

I once heard the fact (I believe from Professor Richard Dawkins) that echolocation has involved independently on four different  occasions: bats, dolphins and two species of cave dwelling birds. How true this is technically, I’m not certain on, considering there are shrews in Madagascar with much lower amplitude, frequency modulated version of echolocation. There is also evidence that echolocation evolved independently in two separate lineages of bats (and I really an lost about how whales fall into this). Although these acoustic techniques can be used by animals to locate their prey quite easily, it also makes it a lot easier for us to find them, especially in the case of dolphins.

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Anderson Localisation Acts As Expected In Experiment

The weak localisation is an effect that occurs when a conductor is taken to a low temperature. It is experimentally seen as the metal in question having an increase of resistivity when it is normally expected for resistivity to decrease at low temperatures and at the critical point, drop to zero. This caused by the fact that at a classical level the electron can be seen as flying through the metal lattice, scattering off the atoms, being led on a random walk. The resistivity, on a quantum level, is the probability of an electron moving between two fixed points. When in regular conditions this is simply the sum of the probabilities of every path between the points. When cold, the quantum regime takes over and an interference term stops being ignorable as it grows in size. These interference terms can be imagined as an increase in the probability that the electron will loop in a circle rather than making any progress and so resistivity increases.

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Reason For Range Of Predicted Temperature Rises

Svante Arrhenius was a Swedish physicist and chemist whose name should be recognisable to anyone who has studied physical chemistry due to his ever relevant Arrhenius equation which describes how a value called the rate constant changes with activation energy and temperature. Apart from physical chemistry he worked on geology and the origin of the ice ages. As part of this study, in 1896, he wrote a paper in which he calculated that the effect of halving the carbon dioxide in the atmosphere would decrease the temperature of Europe by about 4 °C. This was the first prediction linking carbon dioxide to temperature changes ever made and still provides solid evidence for the premise.

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Weekly Roundup 77

Science communication. The idea of trying to explain a scientific comment to some who could be generously described as a layman. The ancient Greek scholars will all have learnt rhetoric and so I can imagine it was sufficiently easier for them to explain an idea to a group of the citizens than it is for scientists now. Ultimately this blog can be seen as a form of science communication which aimed to be a bit more advanced then the sensationalist science stories often found online. For instance typing in “physics” and checking on Google News posits “Have We Been Interpreting Quantum Physics Wrong The Whole Time?” in which the short answer is, probably not. The article is interesting and would certainly be good for a neophyte to science but doesn’t really cover any actual scientific points in any great detail (this is probably an unfair criticism as this particular article is actually considerably above average in this regard but generally the lack of detail is apparent in many newspaper’s science pages). Compare this to the original paper, which is perfectly legible to a scientist but becomes incomprehensible to an ordinary person about half way through the introduction. Bridging the gap between these extremes, and also talking about some more varied science rather than quantum, quantum, relativity and more quantum, would put us a long way forward towards public comprehension of science. The problem is there doesn’t seem to be an easy way to do so. Scientists can’t be expected to start from first principles every time they write a paper and newspapers can’t be incentivised to write in even a mildly technical format when their reader’s average comprehension is below this. The only real solution is to start at the source and provide more thorough science education in school, which, as will seemingly all solutions, requires a lot of money.

Thank you to Natalie Wolchova for the science article which as I said I’ve said I’ve been a bit harsh to to make the point and thank you to Robert Brady and Ross Anderson for the scientific paper. Until tomorrow, goodnight.

Calculating Upper Limit On Coherence In Coronal Mass Ejections

I would hope that every body reading would at least have some idea of what a solar flare is. When eruption on the Sun are great enough it is possible for a coronal mass ejection to occur. This massive release of plasma (weighing up to 100,000,000,000 kg, and considering it’s gas that’s an incredible volume) and magnetic flux which speed away from the Sun at about 1500 km s−1. They can be considered as one of the driving forces for space weather and are also important for understanding the Sun’s magnetic field in the corona. Now at the surface of the Sun, where the magnetic fields permeate, they end up bending back and reconnecting at constantly shifting points. This massive three dimensional structure is known as the magnetic flux ropes.

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