Feb 28, 2013 - By Wearing Different Colored Hats, Over 2,600 Employees At Genentech (in San Francisco)

Hair dryers keeping a paper plane in motion… because science.

Photographs taken of Saturn by NASA. Yes, these are real pictures; they are not illustrations. 

(Source)

Total breakdown in the brain

A stroke is just one example of a condition when communication between nerve cells breaks down. Micro-failures in brain functioning also occur in conditions such as depression and dementia. In most cases, the lost capacity will return after a while. However, consequential damage will often remain so that the functional capability can only be restored through lengthy treatment — if at all. For this reason, researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have been investigating what happens during such breakdown phases and looking at possible ways of preventing damage and speeding up the healing processes. Their findings have been recently published in the eminent journal Scientific Reports.

(Image caption: Nerve cell networks visualised using high-speed fluorescent microscopy and then reconstructed with the software developed by Wrosch and her team. Credit: FAU/Jana Wrosch)

The research team headed by Jana Wrosch of FAU’s Chair of Psychiatry and Psychotherapy found that significant alterations occurred in neural cells while the communication pathways were blocked. Neuron networks reconnect during such periods of inactivity and become hypersensitive. If we imagine that normal communication pathways are motorways, when they are blocked a form of traffic chaos occurs in the brain whereby information is re-routed in disorganised form along what can be called side streets and minor routes. Additional synapses are generated everywhere and begin operating. When the signal is reinstated, the previously coordinated information routes no longer exist and, as in the case of a child, the appropriate functions need to be learned from scratch. Since they are receiving no normal signals during the phase of brain malfunction, the nerve cells also become more sensitive in an attempt to find the missing input. Once the signals return, this means they may overreact.

Nerve cells flicker when stained

Visualising the microscopically minute connections between the nerve cells is a major technical challenge. The conventional microscopic techniques currently available, such as electron microscopy, always require preliminary treatment of the nerve cells that are to undergo examination. However, this causes the nerve cells to die, so that the alterations that occur in the cells cannot be observed. To get round this problem, Wrosch and her team have developed a high-speed microscopy process along with special statistical computer software that make it possible to visualise the communication networks of living neurons. First, a video of the cells is made whereby an image is taken every 36 milliseconds. A special dye is used to stain the cells to ensure that the individual cells flicker whenever they receive a signal. Subsequently, the software recognises these cells on the video images and detects the information pathways by which the signals are transmitted from cell to cell.

The nerve cells are then exposed to the pufferfish poison tetrodotoxin to simulate the blocking of communication channels that occurs in disorders. After inducing communication breakdown phases of varying lengths, the researchers remove the toxin from the cells and determine how the nerve cell networks have changed during exposure. ‘Thanks to this concept, we have been finally able to discover what happens when communication is blocked,’ explains Wrosch. ‘Now we can try to develop medications that will help prevent these damaging changes.’ In future projects, the research team plans to examine the exact mode of action of anti-depressants on nerve cell networks and intends to find new approaches to creating more effective drugs.

An animated chart of 42 North American butterflies

Via Tabletop Whale

Flying to New Heights With the Magnetospheric Multiscale Mission

A mission studying Earth’s magnetic field by flying four identical spacecraft is headed into new territory. 

The Magnetospheric Multiscale mission, or MMS, has been studying the magnetic field on the side of Earth facing the sun, the day side – but now we’re focusing on something else. On February 9, MMS started the three-month-long process of shifting to a new orbit. 

One key thing MMS studies is magnetic reconnection – a process that occurs when magnetic fields collide and re-align explosively into new positions. The new orbit will allow MMS to study reconnection on the night side of the Earth, farther from the sun.

Magnetic reconnection on the night side of Earth is thought to be responsible for causing the northern and southern lights.  

To study the interesting regions of Earth’s magnetic field on the night side, the four MMS spacecraft are being boosted into an orbit that takes them farther from Earth than ever before. Once it reaches its final orbit, MMS will shatter its previous Guinness World Record for highest altitude fix of a GPS.

To save on fuel, the orbit is slowly adjusted over many weeks. The boost to take each spacecraft to its final orbit will happen during the first week of April.

On April 19, each spacecraft will be boosted again to raise its closest approach to Earth, called perigee. Without this step, the spacecraft would be way too close for comfort – and would actually reenter Earth’s atmosphere next winter! 

The four MMS spacecraft usually fly really close together – only four miles between them – in a special pyramid formation called a tetrahedral, which allows us to examine the magnetic environment in three dimensions.

But during orbit adjustments, the pyramid shape is broken up to make sure the spacecraft have plenty of room to maneuver. Once MMS reaches its new orbit in May, the spacecraft will be realigned into their tetrahedral formation and ready to do more 3D magnetic science.

Learn more about MMS and find out what it’s like to fly a spacecraft.

dude seeing these Mega high quality images of the surface of mars that we now have has me fucked up. Like. Mars is a place. mars is a real actual place where one could hypothetically stand. It is a physical place in the universe. ITS JUST OUT THERE LOOKING LIKE UH IDK A REGULAR OLD DESERT WITH LOTS OF ROCKS BUT ITS A WHOLE OTHER PLANET? 

Galaxies: Types and morphology

A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. Galaxies range in size from dwarfs with just a few hundred million (108) stars to giants with one hundred trillion (1014) stars, each orbiting its galaxy’s center of mass.

Galaxies come in three main types: ellipticals, spirals, and irregulars. A slightly more extensive description of galaxy types based on their appearance is given by the Hubble sequence. 

Since the Hubble sequence is entirely based upon visual morphological type (shape), it may miss certain important characteristics of galaxies such as star formation rate in starburst galaxies and activity in the cores of active galaxies.

Ellipticals

The Hubble classification system rates elliptical galaxies on the basis of their ellipticity, ranging from E0, being nearly spherical, up to E7, which is highly elongated. These galaxies have an ellipsoidal profile, giving them an elliptical appearance regardless of the viewing angle. Their appearance shows little structure and they typically have relatively little interstellar matter. Consequently, these galaxies also have a low portion of open clusters and a reduced rate of new star formation. Instead they are dominated by generally older, more evolved stars that are orbiting the common center of gravity in random directions.

Spirals

Spiral galaxies resemble spiraling pinwheels. Though the stars and other visible material contained in such a galaxy lie mostly on a plane, the majority of mass in spiral galaxies exists in a roughly spherical halo of dark matter that extends beyond the visible component, as demonstrated by the universal rotation curve concept.

Spiral galaxies consist of a rotating disk of stars and interstellar medium, along with a central bulge of generally older stars. Extending outward from the bulge are relatively bright arms. In the Hubble classification scheme, spiral galaxies are listed as type S, followed by a letter (a, b, or c) that indicates the degree of tightness of the spiral arms and the size of the central bulge.

Barred spiral galaxy

A majority of spiral galaxies, including our own Milky Way galaxy, have a linear, bar-shaped band of stars that extends outward to either side of the core, then merges into the spiral arm structure. In the Hubble classification scheme, these are designated by an SB, followed by a lower-case letter (a, b or c) that indicates the form of the spiral arms (in the same manner as the categorization of normal spiral galaxies). 

Ring galaxy

A ring galaxy is a galaxy with a circle-like appearance. Hoag’s Object, discovered by Art Hoag in 1950, is an example of a ring galaxy. The ring contains many massive, relatively young blue stars, which are extremely bright. The central region contains relatively little luminous matter. Some astronomers believe that ring galaxies are formed when a smaller galaxy passes through the center of a larger galaxy. Because most of a galaxy consists of empty space, this “collision” rarely results in any actual collisions between stars.

Lenticular galaxy

A lenticular galaxy (denoted S0) is a type of galaxy intermediate between an elliptical (denoted E) and a spiral galaxy in galaxy morphological classification schemes. They contain large-scale discs but they do not have large-scale spiral arms. Lenticular galaxies are disc galaxies that have used up or lost most of their interstellar matter and therefore have very little ongoing star formation. They may, however, retain significant dust in their disks.

Irregular galaxy

An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a spiral or an elliptical galaxy. Irregular galaxies do not fall into any of the regular classes of the Hubble sequence, and they are often chaotic in appearance, with neither a nuclear bulge nor any trace of spiral arm structure.

Dwarf galaxy

Despite the prominence of large elliptical and spiral galaxies, most galaxies in the Universe are dwarf galaxies. These galaxies are relatively small when compared with other galactic formations, being about one hundredth the size of the Milky Way, containing only a few billion stars. Ultra-compact dwarf galaxies have recently been discovered that are only 100 parsecs across.

Interacting

Interactions between galaxies are relatively frequent, and they can play an important role in galactic evolution. Near misses between galaxies result in warping distortions due to tidal interactions, and may cause some exchange of gas and dust. Collisions occur when two galaxies pass directly through each other and have sufficient relative momentum not to merge.

Starburst

Stars are created within galaxies from a reserve of cold gas that forms into giant molecular clouds. Some galaxies have been observed to form stars at an exceptional rate, which is known as a starburst. If they continue to do so, then they would consume their reserve of gas in a time span less than the lifespan of the galaxy. Hence starburst activity usually lasts for only about ten million years, a relatively brief period in the history of a galaxy.

Active galaxy

A portion of the observable galaxies are classified as active galaxies if the galaxy contains an active galactic nucleus (AGN). A significant portion of the total energy output from the galaxy is emitted by the active galactic nucleus, instead of the stars, dust and interstellar medium of the galaxy.

The standard model for an active galactic nucleus is based upon an accretion disc that forms around a supermassive black hole (SMBH) at the core region of the galaxy. The radiation from an active galactic nucleus results from the gravitational energy of matter as it falls toward the black hole from the disc. In about 10% of these galaxies, a diametrically opposed pair of energetic jets ejects particles from the galaxy core at velocities close to the speed of light. The mechanism for producing these jets is not well understood.

The main known types are: Seyfert galaxies, quasars, Blazars, LINERS and Radio galaxy.

source

images: NASA/ESA, Hubble (via wikipedia)

Whenever someone tries to claim that evolution is a lie, I send them a picture of platybelodon.

1. It’s an excellent example of transitional evolution.

2. It’s a mess who would intentionally do this and why

3. It makes them piss themselves a little.

“Evolution is just a theory-”

Monkey sees… monkey knows?

Socrates is often quoted as having said, “I know that I know nothing.” This ability to know what you know or don’t know—and how confident you are in what you think you know—is called metacognition.

When asked a question, a human being can decline to answer if he knows that he does not know the answer. Although non-human animals cannot verbally declare any sort of metacognitive judgments, Jessica Cantlon, an assistant professor of brain and cognitive sciences at Rochester, and PhD candidate Stephen Ferrigno, have found that non-human primates exhibit a metacognitive process similar to humans. Their research on metacognition is part of a larger enterprise of figuring out whether non-human animals are “conscious” in the human sense.

In a paper published in Proceedings of the Royal Society B, they report that monkeys, like humans, base their metacognitive confidence level on fluency—how easy something is to see, hear, or perceive. For example, humans are more confident that something is correct, trustworthy, or memorable—even if this may not be the case—if it is written in a larger font.

“Humans have a variety of these metacognitive illusions—false beliefs about how they learn or remember best,” Cantlon says.

Because other primate species exhibit metacognitive illusions like humans do, the researchers believe this cognitive ability could have an evolutionary basis. Cognitive abilities that have an evolutionary basis are likely to emerge early in development.

“Studying metacognition in non-human primates could give us a foothold for how to study metacognition in young children,” Cantlon says. “Understanding the most basic and primitive forms of metacognition is important for predicting the circumstances that lead to good versus poor learning in human children.”

Cantlon and Ferrigno determined that non-human primates exhibited metacognitive illusions after they observed primates completing a series of steps on a computer:

The monkey touches a start screen.

He sees a picture, which is the sample. The goal is to remember that sample because he will be tested on this later. The monkey touches the sample to move to the next screen.

The next screen shows the sample picture among some distractors. The monkey must touch the image he has seen before.

Instead of getting a reward right away—to eliminate decisions based purely on response-reward—the monkey next sees a betting screen to communicate how certain he is that he’s right. If he chooses a high bet and is correct, three tokens are added to a token bank. Once the token bank is full, the monkey gets a treat. If he gets the task incorrect and placed a high bet, he loses three tokens. If he placed a low bet, he gets one token regardless if he is right or wrong.

Researchers manipulated the fluency of the images, first making them easier to see by increasing the contrast (the black image), then making them less fluent by decreasing the contrast (the grey image).

The monkeys were more likely to place a high bet, meaning they were more confident that they knew the answer, when the contrast of the images was increased.

“Fluency doesn’t affect actual memory performance,” Ferrigno says. “The monkeys are just as likely to get an answer right or wrong. But this does influence how confident they are in their response.”

Since metacognition can be incorrect through metacognitive illusion, why then have humans retained this ability?

“Metacognition is a quick way of making a judgment about whether or not you know an answer,” Ferrigno says. “We show that you can exploit and manipulate metacognition, but, in the real world, these cues are actually pretty good most of the time.”

Take the game of Jeopardy, for example. People press the buzzer more quickly than they could possibly arrive at an answer. Higher fluency cues, such as shorter, more common, and easier-to-pronounce words, allow the mind to make snap judgments about whether or not it thinks it knows the answer, even though it’s too quick for it to actually know.

Additionally, during a presentation, a person presented with large amounts of information can be fairly confident that the title of a lecture slide, written in a larger font, will be more important to remember than all the smaller text below.

“This is the same with the monkeys,” Ferrigno says. “If they saw the sample picture well and it was easier for them to encode, they will be more confident in their answer and will bet high.”