19-year-old Boyan Slat has unveiled plans to create an Ocean Cleanup Array that could remove 7,250,000 tons of plastic waste from the world’s oceans. The device consists of an anchored network of floating booms and processing platforms that could be dispatched to garbage patches around the world. Instead of moving through the ocean, the array would span the radius of a garbage patch, acting as a giant funnel. The angle of the booms would force plastic in the direction of the platforms, where it would be separated from plankton, filtered and stored for recycling.
I feel like I’m getting mixed signals from you, physics.
The little machine is vibrating the molecules of the water at a certain frequency and the stream lets us see the wave of that frequency.
I fucking love physics
Atomically, this is fascinating. It’s a brilliant way to show off one of the features of H20- the way it’s ‘sticks together’ if you like- and this should be shown in schools.
Bursts of Brain Activity May Protect Against Alzheimer’s Disease
Evidence indicates that the accumulation of amyloid-beta proteins, which form the plaques found in the brains of Alzheimer’s patients, is critical for the development of Alzheimer’s disease, which impacts 5.4 million Americans. And not just the quantity, but also the quality of amyloid-beta peptides is crucial for Alzheimer’s initiation. The disease is triggered by an imbalance in two different amyloid species — in Alzheimer’s patients, there is a reduction in a relative level of healthy amyloid-beta 40 compared to 42.
Now Dr. Inna Slutsky of Tel Aviv University’s Sackler Faculty of Medicineand the Sagol School of Neuroscience, with postdoctoral fellow Dr. Iftach Dolev and PhD student Hilla Fogel, have uncovered two main features of the brain circuits that impact this crucial balance. The researchers have found that patterns of electrical pulses (called “spikes”) in the form of high-frequency bursts and the filtering properties of synapses are crucial to the regulation of the amyloid-beta 40/42 ratio. Synapses that transfer information in spike bursts improve the amyloid-beta 40/42 ratio.
This represents a major advance in understanding that brain circuits regulate composition of amyloid-beta proteins, showing that the disease is not just driven by genetic mutations, but by physiological mechanisms as well. Their findings were recently reported in the journal Nature Neuroscience.
Tipping the balance
High-frequency bursts in the brain are critical for brain plasticity, information processing, and memory encoding. To check the connection between spike patterns and the regulation of amyloid-beta 40/42 ratio, Dr. Dolev applied electrical pulses to the hippocampus, a brain region involved in learning and memory.
When increasing the rate of single pulses at low frequencies in rat hippocampal slices, levels of both amyloid-beta 42 and 40 grew, but the 40/42 ratio remained the same. However, when the same number of pulses was distributed in high-frequency bursts, researchers discovered an increased amyloid-beta 40 production. In addition, the researchers found that only synapses optimized to transfer encoded by bursts contributed towards tipping the balance in favor of amyloid-beta 40. Further investigations conducted by Fogel revealed that the connection between spiking patterns and the type of amyloid-beta produced could revolve around a protein called presenilin. “We hypothesize that changes in the temporal patterns of spikes in the hippocampus may trigger structural changes in the presenilin, leading to early memory impairments in people with sporadic Alzheimer’s,” explains Dr. Slutsky.
Behind the bursts
According to Dr. Slutsky, different kinds of environmental changes and experiences — including sensory and emotional experience — can modify the properties of synapses and change the spiking patterns in the brain. Previous research has suggested that a stimulant-rich environment could be a contributing factor in preventing the development of Alzheimer’s disease, much as crossword and similar puzzles appear to stimulate the brain and delay the onset of Alzheimer’s. In the recent study, the researchers discovered that changes in sensory experiences also regulate synaptic properties — leading to an increase in amyloid-beta 40.
In the next stage, Dr. Slutsky and her team are aiming to manipulate activity patterns in the specific hippocampal pathways of Alzheimer’s models to test if it can prevent the initiation of cognitive impairment. The ability to monitor dynamics of synaptic activity in humans would be a step forward early diagnosis of sporadic Alzheimer’s.
cat that is a no
how do cats even work
- A cat can jump up to five times its own height in a single bound.
- The little tufts of hair in a cat’s ear that help keep out dirt direct sounds into the ear, and insulate the ears are called “ear furnishings.”
- The ability of a cat to find its way home is called “psi-traveling.” Experts think cats either use the angle of the sunlight to find their way or that cats have magnetized cells in their brains that act as compasses.
- One reason that kittens sleep so much is because a growth hormone is released only during sleep.
- A cat has 230 bones in its body. A human has 206. A cat has no collarbone, so it can fit through any opening the size of its head.
- A cat’s nose pad is ridged with a unique pattern, just like the fingerprint of a human.
- If they have ample water, cats can tolerate temperatures up to 133 °F.
- A cat’s heart beats nearly twice as fast as a human heart, at 110 to 140 beats a minute.
- Cats don’t have sweat glands over their bodies like humans do. Instead, they sweat only through their paws.
- The claws on the cat’s back paws aren’t as sharp as the claws on the front paws because the claws in the back don’t retract and, consequently, become worn.
- Cats make about 100 different sounds. Dogs make only about 10.
- Researchers are unsure exactly how a cat purrs. Most veterinarians believe that a cat purrs by vibrating vocal folds deep in the throat. To do this, a muscle in the larynx opens and closes the air passage about 25 times per second.
- A cat almost never meows at another cat, mostly just humans. Cats typically will spit, purr, and hiss at other cats.
- A cat’s back is extremely flexible because it has up to 53 loosely fitting vertebrae. Humans only have 34.
- Some cats have survived falls of over 65 feet (20 meters), due largely to their “righting reflex.” The eyes and balance organs in the inner ear tell it where it is in space so the cat can land on its feet. Even cats without a tail have this ability.
- A cat can travel at a top speed of approximately 31 mph (49 km) over a short distance.
- A cat’s hearing is better than a dog’s. And a cat can hear high-frequency sounds up to two octaves higher than a human.
- A cat’s brain is biologically more similar to a human brain than it is to a dog’s. Both humans and cats have identical regions in their brains that are responsible for emotions.
And that’s how cat’s work.
A look at a few astronomical mysteries. (And some great pictures).
We’ve seen a lot of information explaining the wonders of astronomy and space, but what of the mysteries? The realm scientists have yet to fully understand. SPACE has this awesome article getting into a few, 8 in total, of those very areas in the study of the stars that continue to baffle scientists:
The universe has been around for roughly 13.7 billion years, but it still holds many mysteries that continue to perplex astronomers to this day. Ranging from dark energy to cosmic rays to the uniqueness of our own solar system, there is no shortage of cosmic oddities.
The journal Science summarized some of the most bewildering questions being asked by leading astronomers today. In no particular order, here are eight of the most enduring mysteries in astronomy:
8 What is Dark Energy?
Dark energy is thought to be the enigmatic force that is pulling the cosmos apart at ever-increasing speeds, and is used by astronomers to explain the universe’s accelerated expansion.
This elusive force has yet to be directly detected, but dark energy is thought to make up roughly 73 percent of the universe.
7 How Hot is Dark Matter?
Dark matter is an invisible mass that is thought to make up about 23 percent of the universe. Dark matter has mass but cannot be seen, so scientists infer its presence based on the gravitational pull it exerts on regular matter.
Researchers remain curious about the properties of dark matter, such as whether it is icy cold as many theories predict, or if it is warmer.
6 Where are the Missing Baryons?
Dark energy and dark matter combine to occupy approximately 95 percent of the universe, with regular matter making up the remaining 5 percent. But, researchers have been puzzled to find that more than half of this regular matter is missing.
This missing matter is called baryonic matter, and it is composed of particles such as protons and electrons that make up majority of the mass of the universe’s visible matter.
Some astrophysicists suspect that missing baryonic matter may be found between galaxies, in material known as warm-hot intergalactic medium, but the universe’s missing baryons remain a hotly debated topic.
5 How do Stars Explode?
When massive stars run out of fuel, they end their lives in gigantic explosions called supernovas. These spectacular blasts are so bright they can briefly outshine entire galaxies.
Extensive research and modern technologies have illuminated many details about supernovas, but how these massive explosions occur is still a mystery.
Scientists are keen to understand the mechanics of these stellar blasts, including what happens inside a star before it ignites as a supernova.
4 What Re-ionized the Universe?
The broadly accepted Big Bang model for the origin of the universe states that the cosmos began as a hot, dense point approximately 13.7 billion years ago.
The early universe is thought to have been a dynamic place, and about 13 billion years ago, it underwent a so-called age of re-ionization. During this period, the universe’s fog of hydrogen gas was clearing and becoming translucent to ultraviolet light for the first time.
Scientists have long been puzzled over what caused this re-ionization to occur.
3 What’s the Source of the Most Energetic Cosmic Rays?
Cosmic rays are highly energetic particles that flow into our solar system from deep in outer space, but the actual origin of these charged subatomic particles has perplexed astronomers for about a century.
The most energetic cosmic rays are extraordinarily strong, with energies up to 100 million times greater than particles that have been produced in manmade colliders. Over the years, astronomers have attempted to explain where cosmic rays originate before flowing into the solar system, but their source has proven to be an enduring astronomical mystery.
2 Why is the Solar System so Bizarre?
As alien planets around other stars are discovered, astronomers have tried to tackle and understand how our own solar system came to be.
The differences in the planets within our solar system have no easy explanation, and scientists are studying how planets are formed in hopes of better grasping the unique characteristics of our solar system.
This research could, in fact, get a boost from the hung for alien worlds, some astronomers have said, particularly if patterns arise in their observations of extrasolar planetary systems.
1 Why is the Sun’s Corona so Hot?
The sun’s corona is its ultra-hot outer atmosphere, where temperatures can reach up to a staggering 10.8 million degrees Fahrenheit (6 million degrees Celsius).
Solar physicists have been puzzled by how the sun reheats its corona, but research points to a link between energy beneath the visible surface, and processes in the sun’s magnetic field. But, the detailed mechanics behind coronal heating are still unknown.
Black Holes Have Properties That Resemble Dynamics of Both Solids and Liquids
Black holes are surrounded by many mysteries, but now researchers from the Niels Bohr Institute, among others, have come up with new groundbreaking theories that can explain several of their properties. The research shows that black holes have properties that resemble the dynamics of both solids and liquids.
Black holes are extremely compact objects in the universe. They are so compact that they generate an incredibly strong gravitational pull and everything that comes near them is swallowed up. Not even light can escape, so light that hits a black hole will not be reflected, but will be entirely absorbed, as a result, they cannot be seen and we call them black holes.
“But black holes are not completely black, because we know that they emit radiation and there are indications that the radiation is thermal, i.e. it has a temperature,” explains Niels Obers, a professor of theoretical particle physics and cosmology at the Niels Bohr Institute at the University of Copenhagen.
Researchers know that the black holes are very compact, but they do not know what their quantum properties are. Niels Obers works with theoretical modelling to better understand the physics of black holes. He explains that you can look at a black hole like a particle. A particle has in principle no dimensions. It is a point. If you give a particle an extra dimension, it becomes a string. If you give the string an extra dimension, it becomes a plane. Physicists call such a plane a ‘brane’ (the word ‘brane’ is related to ‘membrane’ from the biological world).
“In string theory, you can have different branes, including planes that behave like black holes, which we call black branes. The black branes are thermal, that is to say, they have a temperature and are dynamical objects. When black branes are folded into multiple dimensions, they form a ‘blackfold’,” explains Niels Obers, who worked out this new way of looking at black branes with associate professor in theoretical physics at the Niels Bohr Institute, Troels Harmark, back in 2009.
Niels Obers and his two doctoral students Jay Armas and Jakob Gath have now made a new breakthrough in the description of the physics of black holes based on the theories of the black branes and blackfolds,
“The black branes are hydro-dynamic objects, that is to say that they have the properties of a liquid. We have now discovered that black branes also have properties, which can be explained in terms of solids. They can behave like elastic material when we bend them,” explains Jay Armas.
He explains that when the black branes are bent and folded into a blackfold, a so-called piezoelectric effect (electricity that occurs due to pressure) is created. This new effect can be understood as a slightly bent and charged black string with a greater concentration of electric charge on the innermost side in relation to the outermost side. This produces two electrically charged poles on the black strings. Black holes are predicted by Einstein’s theory of gravity. This means that there is a very surprising relationship between gravity and fluid mechanics and solid-state physics.
“With these new theories, we expect to be able to explain other black hole phenomena, and we expect to be able to better understand the physical properties of neutron stars. We also expect to gain a greater understanding of the so-called particle theories, which are, for example, relevant for understanding the quark-gluon-plasma in the primordial universe,” explains Niels Obers.
Physicists have teleported quantum information from one ensemble of atoms to another 150 metres away, a demonstration that paves the way towards quantum routers and a quantum internet
Lights Out: Why does it get dark at night? The answer might be more complicated than you think.
My face while watching this video:
Is it weird that this made perfect sense to me?
That was an awesome explanation. Watch the video.
MY WHOLE LIFE IS A LIE
I LOVE things like this, I find it so incredibly fascinating.
Get it because it’s a CELL WALL
oh my god
I hope people don’t stop giving a shit about this in a week or two.
This is what Mars looks like. Hey everyone, this is what Mars looks like. We didn’t know this yesterday.
WOW this is so cool! So barren and beautiful. And lonely.
Well we actually did know what it looks like, my dad has a fat book of HQ photos from the other rovers. But this is really cool
20 Things You Didn’t Know About Relativity
Galileo invented it, Einstein understood it, and Eddington saw it.
1 Who invented relativity? Bzzzt—wrong. Galileo hit on the idea in 1639, when he showed that a falling object behaves the same way on a moving ship as it does in a motionless building.
2 And Einstein didn’t call it relativity. The word never appears in his original 1905 paper, “On the Electrodynamics of Moving Bodies,” and he hated the term, preferring “invariance theory” (because the laws of physics look the same to all observers—nothing “relative” about it).
3 Space-time continuum? Nope, that’s not Einstein either. The idea of time as the fourth dimension came from Hermann Minkowski, one of Einstein’s professors, who once called him a “lazy dog.”
4 But Einstein did reformulate Galileo’s relativity to deal with the bizarre things that happen at near-light speed, where time slows down and space gets compressed. That counts for something.
6 Never heard of Hasenöhrl? That’s because he failed to connect the equation with the principle of relativity. Verdammt!
7 Einstein’s full-time job at the Swiss patent office meant he had to hash out relativity during hours when nobody was watching. He would cram his notes into his desk when a supervisor came by.
8 Although Einstein was a teetotaler, when he finally completed his theory of relativity, he and his wife, Mileva, drank themselves under the table—the old-fashioned way to mess with the space-time continuum.
9 Affection is relative. “I need my wife, she solves all the mathematical problems for me,” Einstein wrote while completing his theory in 1904. By 1914, he’d ordered her to “renounce all personal relations with me, as far as maintaining them is not absolutely required for social reasons.”
10 Rules are relative too. According to Einstein, nothing travels faster than light, but space itself has no such speed limit; immediately after the Big Bang, the runaway expansion of the universe apparently left light lagging way behind.
11 Oh, and there are two relativities. So far we’ve been talking about special relativity, which applies to objects moving at constant speed. General relativity, which covers accelerating things and explains how gravity works, came a decade later and is regarded as Einstein’s truly unique insight.
12 Pleasure doing business with you, chum(p): When Einstein was stumped by the math of general relativity, he relied on his old college pal Marcel Grossmann, whose notes he had studied after repeatedly cutting class years earlier.
13 Despite that, the early version of general relativity had a major error, a miscalculation of the amount a light beam would bend due to gravity.
14 Fortunately, plans to test the theory during a solar eclipse in 1914 were scuttled by World War I. Had the experiment been conducted then, the error would have been exposed and Einstein would have been proved wrong.
15 The eclipse experiment finally happened in 1919 (you’re looking at it on this very page). Eminent British physicist Arthur Eddington declared general relativity a success, catapulting Einstein into fame and onto coffee mugs.
16 In retrospect, it seems that Eddington fudged the results, throwing out photos that showed the “wrong” outcome.
17 No wonder nobody noticed: At the time of Einstein’s death in 1955, scientists still had almost no evidence of general relativity in action.
18 That changed dramatically in the 1960s, when astronomers began to discover extreme objects—neutron stars and black holes—that put severe dents in the shape of space-time.
19 Today general relativity is so well understood that it is used to weigh galaxies and locate distant planets by the way they bend light.
20 If you still don’t get Einstein’s ideas, try this explanation reportedly from The Man Himself: “Put your hand on a hot stove for a minute and it seems like an hour. Sit with a pretty girl for an hour and it seems like a minute. That’s relativity.”
(from Greek κύτος, kytos, “a hollow”; and -λογία, -logia) “the study of cells”. Cytology is the branch of life science which deals with the study of cells in terms of structure, function and chemistry.
David Goodsell is one of my very, very favorite artists.
One of my favorites too.