A World Of Languages - And How Many Speak Them

DEC terminal finds itself viscously attacked by a bear. 

Join the movement to make two years of community college as free and universal as high school is today at HeadsUpAmerica.us/Act.

What movie best represent each US state (according to subtonix)?

Pretty cool

Just the other week, Baltimore Ravens offensive lineman John Urschel co-published a paper in the Journal of Computational Mathematics. The paper “A Cascadic Multigrid Algorithm for Computing the Fiedler Vector of Graph Laplacians” can be found on arXiv.

In an article for the Player’s Tribune, Urschel says, “I am a mathematical researcher in my spare time, continuing to do research in the areas of numerical linear algebra, multigrid methods, spectral graph theory and machine learning. I’m also an avid chess player, and I have aspirations of eventually being a titled player one day.”

This reminded me of this tumblr post by classidiot I saw the other day that describes how it’s common to see mathematicians that are proficient in some non-mathematical hobby (playing an instrument, dancing, hiking, so on…), but often not the other way around. I think it’s really fantastic that John Urschel does mathematics just on the side as something he truly enjoys.

Computational Hydrographic Printing

Method developed at Columbia University can accurately apply a print designed for specific surface shape from flat printouts. Interesting to note that this method can compliment 3D Printing with a standard home printer:

Hydrographic printing is a well-known technique in industry for transferring color inks on a thin film to the surface of a manufactured 3D object. It enables high-quality coloring of object surfaces and works with a wide range of materials, but suffers from the inability to accurately register color texture to complex surface geometries. Thus, it is hardly usable by ordinary users with customized shapes and textures. We present computational hydrographic printing, a new method that inherits the versatility of traditional hydrographic printing, while also enabling precise alignment of surface textures to possibly complex 3D surfaces.

More Here

Average rent in Berlin shown as heat map on the transit map.

(Image caption: The prefrontal cortex connects to a very specific region of the brainstem (the PAG) through prefrontal cortical neurons: those labeled in purple directly project to the PAG and control our instinctive behaviours. Credit: EMBL/Livia Marrone)

Neural connection keeps instincts in check

From fighting the urge to hit someone to resisting the temptation to run off stage instead of giving that public speech, we are often confronted with situations where we have to curb our instincts. Scientists at EMBL have traced exactly which neuronal projections prevent social animals like us from acting out such impulses. The study, published online in Nature Neuroscience, could have implications for schizophrenia and mood disorders like depression.

“Instincts like fear and sex are important, but you don’t want to be acting on them all the time,” says Cornelius Gross, who led the work at EMBL. “We need to be able to dynamically control our instinctive behaviours, depending on the situation.”

The driver of our instincts is the brainstem – the region at the very base of your brain, just above the spinal cord. Scientists have known for some time that another brain region, the prefrontal cortex, plays a role in keeping those instincts in check (see background information down below). But exactly how the prefrontal cortex puts a break on the brainstem has remained unclear.

Now, Gross and colleagues have literally found the connection between prefrontal cortex and brainstem. The EMBL scientists teamed up with Tiago Branco’s lab at MRC LMB, and traced connections between neurons in a mouse brain. They discovered that the prefrontal cortex makes prominent connections directly to the brainstem.

Gross and colleagues went on to confirm that this physical connection was the brake that inhibits instinctive behaviour. They found that in mice that have been repeatedly defeated by another mouse – the murine equivalent to being bullied – this connection weakens, and the mice act more scared. The scientists found that they could elicit those same fearful behaviours in mice that had never been bullied, simply by using drugs to block the connection between prefrontal cortex and brainstem.

These findings provide an anatomical explanation for why it’s much easier to stop yourself from hitting someone than it is to stop yourself from feeling aggressive. The scientists found that the connection from the prefrontal cortex is to a very specific region of the brainstem, called the PAG, which is responsible for the acting out of our instincts. However, it doesn’t affect the hypothalamus, the region that controls feelings and emotions. So the prefrontal cortex keeps behaviour in check, but doesn’t affect the underlying instinctive feeling: it stops you from running off-stage, but doesn’t abate the butterflies in your stomach.

The work has implications for schizophrenia and mood disorders such as depression, which have been linked to problems with prefrontal cortex function and maturation.

“One fascinating implication we’re looking at now is that we know the pre-frontal cortex matures during adolescence. Kids are really bad at inhibiting their instincts; they don’t have this control,” says Gross, “so we’re trying to figure out how this inhibition comes about, especially as many mental illnesses like mood disorders are typically adult-onset.”

Mercator projection with a different centerpoint.