This is a repository for all cool scientific discussion and fascination. Scientific facts, theories, and overall cool scientific stuff that you'd like to share with others. Stuff that makes you smile and wonder at the amazing shit going on around us, that most people don't notice.
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Originally Posted by Discuss Thrower:
Great, we know where the enemy lives. Now how do we kill them all?
You can buy this cure-foam for 3 easy installments of $39.95! Call within the next 10-minutes and they will include another 4oz bottle absolutely free! (just pay 12.99 s&h) [Reply]
Originally Posted by tooge:
So do these little face mite dudes tails get chopped off when I shave? do they grow new ones or do they live without thier jabba the hut looking tails? wtf?
I bet that when you chop off their tails with your razor, it makes 2 worms out of both pieces like an earthworm. Probably best to quit shaving.. :-)
Also, it's not noted in the article I posted, but these little face mite critters don't actually have a butthole. Yeah... no butthole at all. They simply eat over their very short lifetime, and fill up with shit, and then die. Never once feeling the sweet release of pinching a loaf.... [Reply]
Originally Posted by KC Fish:
I bet that when you chop off their tails with your razor, it makes 2 worms out of both pieces like an earthworm. Probably best to quit shaving.. :-)
Also, it's not noted in the article I posted, but these little face mite critters don't actually have a butthole. Yeah... no butthole at all. They simply eat over their very short lifetime, and fill up with shit, and then die. Never once feeling the sweet release of pinching a loaf....
Yeah it's in there, they just called it an excretory opening. Lol Posted via Mobile Device [Reply]
Controlling Brains With a Flick of a Light Switch
Using the new science of optogenetics, scientists can activate or shut down neural pathways, altering behavior and heralding a true cure for psychiatric disease.
by Amy Barth
From the September 2012 issue; published online September 25, 2012
Stopped at a red light on his drive home from work, Karl Deisseroth contemplates one of his patients, a woman with depression so entrenched that she had been unresponsive to drugs and electroshock therapy for years. The red turns to green and Deisseroth accelerates, navigating roads and intersections with one part of his mind while another part considers a very different set of pathways that also can be regulated by a system of lights. In his lab at Stanford University’s Clark Center, Deisseroth is developing a remarkable way to switch brain cells off and on by exposing them to targeted green, yellow, or blue flashes. With that ability, he is learning how to regulate the flow of information in the brain.
Deisseroth’s technique, known broadly as optogenetics, could bring new hope to his most desperate patients. In a series of provocative experiments, he has already cured the symptoms of psychiatric disease in mice. Optogenetics also shows promise for defeating drug addiction. When Deisseroth exposed a set of test mice to cocaine and then flipped a switch, pulsing bright yellow light into their brains, the expected rush of euphoria—the prelude to addiction—was instantly blocked. Almost miraculously, they were immune to the cocaine high; the mice left the drug den as uninterested as if they had never been exposed.
Today, those breakthroughs have been demonstrated in only a small number of test animals. But as Deisseroth pulls into his driveway he is optimistic about what tomorrow’s work could bring: Human applications, and the relief they could deliver, may not be far off.
For all its complexity, the brain in some ways is a surprisingly simple device. Neurons switch off and on, causing signals to stop or go. Using optogenetics, Deisseroth can do that switching himself. He inserts light-sensitive proteins into brain cells. Those proteins let him turn a set of cells on or off just by shining the right kind of laser beam at the cells.
That in turn makes it possible to highlight the exact neural pathways involved in the various forms of psychiatric disease. A disruption of one particular pathway, for instance, might cause anxiety. To test the possibility, Deisseroth engineers an animal with light-sensitive proteins in the brain cells lying along the suspected pathway. Then he illuminates those cells with a laser. If the animal begins cowering in a corner, he knows he is in the right place. And as Deisseroth and his colleagues illuminate more neural pathways, other researchers will be able to design increasingly targeted drugs and minimally invasive brain implants to treat psychiatric disease.
[...]
Crick’s idea was that light, with its unparalleled speed and precision, could be the ideal tool for controlling neurons and mapping the brain. “The idea of an energy interface instead of a physical interface to work with the brain was what was so exciting,” Deisseroth says. He thought creating a light-sensitive brain was probably impossible, but then an idea floated up: What about tapping the power of light-sensitive microbes, single-celled creatures that drift in water, turning toward or away from the sun to regulate energy intake? Such brainless creatures rely on signals from light-sensitive proteins called opsins. When sunlight hits the opsin, it instantly sends an electric signal through the microbe’s cell membrane, telling the tiny critter which way to turn in relation to the sun.
Deisseroth wondered if he could insert these opsins into targeted mammalian brain cells in order to make them light-sensitive too. If so, he could learn to control their behavior using light. Shining light into the brain could then become the tool Crick imagined, providing a way to control neurons without electric shocks or slow-acting, unfocused drugs.
Lighting the Brain
The necessary tools were already out there. The first opsin—the light-sensitive protein made by microbes—had been identified in 1971, the same year Deisseroth was born. Bacteriorhodopsin, as it was called, responded to green light, and scientists have since found it in microbes living in saltwater all over the world. The next opsin, halorhodopsin, which responds to yellow light, was discovered in 1977. Like bacteriorhodopsin, it was found in bacteria living in salty lakes and seas.
Deisseroth, who read everything he could about opsins, realized that light-sensitive microbes speak the same basic language as neurons: When light hits the opsin, gates in the cell membrane open, allowing charged particles called ions to flow in and out. In microbes, ion flow tells the organism which way to turn. In neurons, ions flowing through the cell wall initiate action, setting off a string of communications that tell organisms like us how to feel and behave. This similarity suggested to Deisseroth that opsins could be manipulated to switch brain cells on and off.
The pistol shrimp... the noisiest creature in the ocean. Colonies of them make a distinct snapping noise that overshadows nearly all other sounds throughout the world's oceans, including the calls of some whales. In fact, they are so loud, their snapping sounds interfere with military and scientific sonar (so much so, that hostile submarines have used large colonies of pistol shrimps to hide!).
So how on earth does the pistol shrimp, which can be anywhere from a couple centimeters to a couple inches in length, make such a loud sound? They possess an oversized claw which they close shut quickly enough to move water over 60 mph, creating a cavitation bubble in its wake. This bubble exists for a tiny fraction of a second (between 10 nanoseconds and 300 picoseconds), but it becomes so hot (over 8,540F) that it emits light. The cavitation bubble finally collapses and creates a bang as loud as 218 decibels. As a comparison, the space shuttle launch was as loud as 170~ decibels.
Now the next question; why? These shrimp use their super claws to stun prey. The shockwave from the collapse of the shrimp's claw is enough to stun small shrimp and fish and kill them.. without even touching them. They also compete and fight with one another to see who is louder. Overall... this shrimp is pretty awesome. [Reply]
Originally Posted by h5n1:
yeah, it's only 9.8m/s squared. HOWEVER, do you realize how far it is from the surface of the earth to the core? 6384 km at the equator. in meters, that's 6.384 million meters. you'll hit terminal velocity at a certain point, and assuming you don't have a parachute (which wouldn't work in a vacuum anyway), you would most assuredly die of acceleration alone
(note: I could easily be wrong on this. I'm relying on physics I a few years ago in my undergrad; there's a reason I went into genetics rather than physics--pretty sure my reasoning here is sound, don't feel like digging out a textbook, pen and paper)
The acceleration would start at 9.81 m/(s^2) but the mass of the earth above your falling head would also create a gravitational pull above your head trying to pull you back up. This oppositional gravitational force would be less than the earths but would be sufficient to slow you down. Once at the center the force due to gravity would be the same on all sides (almost, the earth isn't truly spherical but a prolate spheroid) but the conversion of all that gravitational potential energy to kinetic energy would push you past the center where the exact same effects would occur in the opposite direction resulting in a gentle stop at the other side [Reply]
Norwegian researchers are the world’s first to develop a method for producing semiconductors from graphene. This finding may revolutionise the technology industry.
The method involves growing semiconductor-nanowires on graphene. To achieve this, researchers “bomb” the graphene surface with gallium atoms and arsenic molecules, thereby creating a network of minute nanowires.
The result is a one-micrometre thick hybrid material which acts as a semiconductor. By comparison, the silicon semiconductors in use today are several hundred times thicker. The semiconductors’ ability to conduct electricity may be affected by temperature, light or the addition of other atoms. Grafen consists of a single layer of carbon atoms. (Illustration: Wikimedia Commons). Fantastic potential
Graphene is the thinnest material known, and at the same time one of the strongest. It consists of a single layer of carbon atoms and is both pliable and transparent. The material conducts electricity and heat very effectively. And perhaps most importantly, it is very inexpensive to produce.
“Given that it’s possible to make semiconductors out of graphene instead of silicon, we can make semiconductor components that are both cheaper and more effective than the ones currently on the market,” explains Helge Weman of the Norwegian University of Science and Technology (NTNU). Dr Weman is behind the breakthrough discovery along with Professor Bjørn-Ove Fimland.
“A material comprising a pliable base that is also transparent opens up a world of opportunities, one we have barely touched the surface of,” says Dr Weman. “This may bring about a revolution in the production of solar cells and LED components. Windows in traditional houses could double as solar panels or a TV screen. Mobile phone screens could be wrapped around the wrist like a watch. In short, the potential is tremendous.” Broad-based public funding
The researchers have received assistance in gaining patents and founding a company from NTNU Technology Transfer AS, a collaborative partner to the programme entitled Commercialising R&D Results (FORNY2020) at the Research Council of Norway.
However, the path to these remarkable findings started with basic research funded under the Research Council’s Clean Energy for the Future Programme (RENERGI) and the now-concluded programme, Nanotechnology and New Materials (NANOMAT), which initiated the findings.
This video explains the new material. (Video: CrayNano AS) Huge interest among electronics giants
The researchers will now begin to create prototypes directed towards specific areas of application. They have been in contact with giants in the electronics industry such as Samsung and IBM. “There is tremendous interest in producing semiconductors out of graphene, so it shouldn’t be difficult to find collaborative partners,” Dr Weman adds.
The researchers are hoping to have the new semiconductor hybrid materials on the commercial market in roughly five years.