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Ion channels are crucial for neural communication; they control the flow and gradient of charged particles, creating electrical signals. Recent work report | Neuroscience.


In this study, the researchers assessed how dense ion channels were packed in the membranes of neuronal cells from ten species of mammals, including mice, rats, rabbits, ferrets, macaques, marmosets, macaques, humans, and one of the smallest known mammals, an animal called the Etruscan shrew. The team focused on a type of excitatory neuron typically found in the cortex of the brain, and three ion channels that are in the membranes of those cells; two are voltage-gated ion channels that control the movement of potassium, another is called the HCN channel and both potassium and sodium ions can flow through it.

Studies have suggested that the human brain is built like the brains of other mammals, said first study author Lou Beaulieu-Laroche, a former MIT graduate student. It was once thought that in mammals, these channels would be present at about the same density from one species to another.

For centuries, people have dreamed of being driven at speed across the vast oceans of space by winds of light.

As whimsical as the idea sounds, nudging reflective sails slowly towards the speed of light using nothing more than the punch of photons might be our only plausible shot at reaching another star inside of a single human lifetime.

It’s also far easier said than done. Particles of light might be fast, but they don’t push very hard. If you make a sail light enough to feel the inertia of radiation, then the constant barrage of photons could inadvertently damage its material.

The detection of cosmic rays is rare – however the latest detection is even rarer as it appears to be going in the wrong direction.

Cosmic rays are bombarding the Earth every day and are measured at observing sites across the world, with the most notable being located at the Earths south pole.

Not to be fooled by their historical name, cosmic rays generally refer to high energy particles with mass whereas high energy in the form of gamma rays and/or X-rays are photons. These cosmic particles were discovered in 1912 by Victor Hess when he ascended to 5,300 meters above sea level in a hot air balloon and detected significantly increased levels of ionization in the atmosphere.

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Objective Collapse Theories offer a explanation of quantum mechanics that is at once brand new and based in classical mechanics. In the world of quantum mechanics, it’s no big deal for particles to be in multiple different states at the same time, or to teleport between locations, or to influence each other faster than light. But somehow, none of this strangeness makes its way to the familiar scale of human beings — even though our world is made entirely of quantum-weird building blocks. The explanations of this transition range from the mystical influence of the conscious mind to the grandiose proposition of multiple realities. But Objective Collapse Theories feels as down to earth as the classical world that we’re trying to explain. Let’s see if it makes any sense.

Physicists have predicted the existence of dark matter, a material that does not absorb, emit or reflect light, for decades. While there is now significant evidence hinting to the existence of dark matter in the universe, as it was never directed detected before its composition remains unknown.

In recent years, researchers worldwide have made different hypotheses about the composition of this elusive material and tried to test them experimentally. Many have suggested that it could be comprised of new and previously unobserved types of elementary particles, such as axions and weakly interactive massive particles (WIMPs).

A few weeks ago, two large research collaborations, the PandaX-4T and the ADMX Collaborations, published the results of two new dark matter searches based on different hypothesis. In their study, featured in Physical Review Letters, the PandaX-4T Collaboration tried searching for signs of a new elementary particle in data collected using a time projection chamber at the China Jinping Underground Laboratory (CJPL), the deepest underground lab in world.

The world’s most precise atomic clock has confirmed that the time dilation predicted by Albert Einstein’s theory of general relativity works on the scale of millimetres.

Physicists have been unable to unite quantum mechanics – a theory that describes matter at the smallest scales – with general relativity, which predicts the behaviour of objects at the largest cosmic scales, including how gravity bends space-time. Because gravity is weak over small distances, it is hard to measure relativity on small scales.

But atomic clocks, which count seconds by measuring the frequency of radiation emitted when electrons around an atom change energy states, can detect these minute gravitational effects.

Decaying isotopes of hydrogen have just given us the smallest measurement yet of the mass of a neutrino.

By measuring the energy distribution of electrons released during the beta decay of tritium, physicists have determined that the upper limit for the mass of the electron antineutrino is just 0.8 electronvolts. That’s 1.6 × 10–36 kilograms in metric mass, and very, very freaking small in imperial.

Although we still don’t have a precise measurement, narrowing it down brings us closer to understanding these strange particles, the role they play in the Universe, and the impact they could have on our current theories of physics. The achievement was made at the Karlsruhe Tritium Neutrino Experiment (KATRIN) in Germany.

The Joint European Torus (JET) fusion reactor in the UK has generated the highest level of sustained energy ever from atom fusion. On December 21st, 2021, the “tokamak” reactor produced 59 megajoules of energy during a five-second fusion pulse. That’s double what it created back in 1997. (Yes, I know energy is not created or destroyed, but you get what I mean!)

The JET reactor is the flagship experimental device of the European Fusion Program, funded by the EU. It’s mainly designed to prove scientists’ modeling efforts, with an eye on future, bigger experiments with a much larger ITER reactor in France, set to start fusion testing in 2025.

JET hit a Q value of 0.33, meaning it produced about a third of the energy put in. The highest Q value achieved so far is 0.7 by the US Department of Energy’s National Ignition Facility, but it only hit that figure for 4 billionths of a second. The goal with ITER is to reach a Q factor of 10 or greater. Fun fact: ITER isn’t an acronym but means “the path” in Latin. And now you know.

Nuclear power may not be as bad as you think. If we used Thorium instead of Uranium, we could greatly decrease dangerous radioactive by-products. There is enough Thorium in the world to meet all our energy needs for over 1,000 years.

In this video I show you how nuclear power plants work, and how Thorium can change the game. I aim to shift your views on nuclear power.

This is how energy is created in a nuclear reactor: When you split some heavier atoms into two lighter atoms, you get a lot of energy. For example, if you hit an isotope of Uranium, Uranium-235 with a neutron at the right speed, it will split into two lighter atoms like barium-141 and krypton-92 & 3 neutrons. These neutrons then split other U-235 atoms, leading to a chain reaction, producing more and more energy.