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Chris Genly
Works at Coherent Logix
Attended Massachusetts Institute of Technology
Lived in Forest Grove, oregon
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Chris Genly

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A nice "proof without words" of the fact that the sum of the first n squares has the form n(n+1)(2n+1)/6

See also https://en.wikipedia.org/wiki/Square_pyramidal_number for more about these numbers.
I made gif animations of Sum of Square Numbers. This explanation is by Takemasa Ooya. http://www.h6.dion.ne.jp/~ooya/Suugaku/index.html http://www.h6.dion.ne.jp/~ooya/Suugaku/SigmaK2.pdf See...
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Chris Genly

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I'd be interested in seeing the inner workings of an old ASCII teletype. They were mechanical marvels converting a serial data signal to a printed character.
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Dance of the Moon

As the New Horizons spacecraft approaches Pluto, there’s a great deal of anticipation about just what we’ll learn about the dwarf planet. One of the key areas of interest is Pluto’s moon system. We know that Pluto has at least five moons, with Charon being the largest by far, and four smaller moons Styx, Nix, Hydra and Kerberos. From Hubble observations, we know that Hydra and Nix seem to have oblong shapes. We know this from their varying brightness over time, which suggests that their rotation means that sometimes a wide side faces us (making it appear brighter) and other times a narrow side faces us (appearing dimmer). There’s a small chance that this variation in brightness could be due to a radically different albedo on different sides of the moons, but that isn’t likely to be the case. In fact recent research on Nix would further points to its elongated shape.

By our best estimates, Nix is shaped roughly like an American football, and is about 57 km on its long side and 27 km along its short side. Because of this irregular shape, the gravitational pull of Pluto and Charon exert a twisting force (torque) on the small moon. If Nix simply orbited a single mass, then this torque effect would tend to stabilize the moon, and perhaps even cause it to tidally lock similar to the way our Moon is tidally locked to Earth. But because Nix is pulled by two large bodies orbiting each other, the torque is irregular. Recent computer simulations show that Nix would therefore have a chaotic motion where its rotation doesn’t follow a regular pattern. As a result, the apparent brightness of Nix should vary in a chaotic way.

This is what Hubble observations find. If Nix were roughly spherical and its brightness variations were simply due to varying albedo, we would expect them to follow a regular pattern. So it would seem that Nix is truly oblong. Of course to know for sure, we’d like to get some direct images of the small moon, which we’ll hopefully get during the Pluto flyby.
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UVA Med School researchers have determined that the brain is directly connected to the immune system by vessels previously thought not to exist.

Kevin Lee, PhD, chairman of the UVA Department of Neuroscience, described his reaction to the discovery: "The first time these guys showed me the basic result, I just said one sentence: 'They'll have to change the textbooks.' There has never been a lymphatic system for the central nervous system, and it was very clear from that first singular observation - and they've done many studies since then to bolster the finding - that it will fundamentally change the way people look at the central nervous system's relationship with the immune system."

"Instead of asking, 'How do we study the immune response of the brain?' 'Why do multiple sclerosis patients have the immune attacks?' now we can approach this mechanistically. Because the brain is like every other tissue connected to the peripheral immune system through meningeal lymphatic vessels," said Jonathan Kipnis, PhD, professor in the UVA Department of Neuroscience and director of UVA's Center for Brain Immunology and Glia (BIG). "It changes entirely the way we perceive the neuro-immune interaction. We always perceived it before as something esoteric that can't be studied. But now we can ask mechanistic questions."

The unexpected presence of the lymphatic vessels raises a tremendous number of questions that now need answers, both about the workings of the brain and the diseases that plague it. For example, take Alzheimer's disease. "In Alzheimer's, there are accumulations of big protein chunks in the brain," Kipnis said. "We think they may be accumulating in the brain because they're not being efficiently removed by these vessels." He noted that the vessels look different with age, so the role they play in aging is another avenue to explore. And there's an enormous array of other neurological diseases, from autism to multiple sclerosis, that must be reconsidered in light of the presence of something science insisted did not exist.

#biology   #neuroscience   #scienceeveryday   #sciencesunday  
In a stunning discovery that overturns decades of textbook teaching, researchers at the University of Virginia School of Medicine have determined that the brain is directly connected to the immune system by vessels previously thought not to exist. The discovery could have profound implications for diseases from autism to Alzheimer's to multiple sclerosis.
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Heads up! +California Academy of Sciences has added over 200 3D animal #skulls to +Google Art Project.

Check out all the lovely bones here: https://www.google.com/culturalinstitute/collection/california-academy-of-sciences

Below: Macropus rufus (Red Kagaroo), California Academy of Sciences specimen 30163
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NASA’ is working on an experimental wing that could finally eliminate the massive advantage exploding jet fuel has over batteries when it comes to keeping planes in the sky.
The Leading Edge Asynchronous Propeller Technology (LEAPTech) wing has 18 electrically powered propellers attached to it.
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The electrostatic motor is extremely simple, it has no coils and no magnets. 
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An artificial intelligence system has for the first time reverse-engineered the regeneration mechanism of planaria—the small worms whose extraordinary power to regrow body parts has made them a research model in human regenerative medicine.
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"Eric Keller is a computer animator by day and a bug nerd by night. Now he's found a way to combine his two passions by using his CGI skills to explore entomology. In the first episode of his series, "Entomology Animated," he uses stunning 3D graphics to explain the biology of the fire ant's painful sting.

The red imported fire ant (Solenopsis invicta) is a native of South America, but as its name suggests, the critter has managed to invade North America, Australia, the Caribbean and eastern Asia. Their status as "pest" isn't just because of their venom-filled sting; their nests can disrupt agricultural processes. The ants' mounds destroy plant roots and can muck up mechanical cultivation processes, both of which lead to a loss of crops. They also eat just about everything else. When they're gobbling up other pests, that's arguably a good thing; when they're chowing down on native pollinators it's undeniably bad.

Either way, they're captivating little critters, with – as you'll learn in the video above – a set of quite clever behaviours meant to subdue their opponents." - via +Joanne Manaster.
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The dangers of innovative teaching
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In his circles
708 people
Have him in circles
346 people
Jamie Kenward's profile photo
David Shellabarger's profile photo
Al Stefanelli's profile photo
Mark Bretl's profile photo
Viet Nguyen's profile photo
Anna Craig's profile photo
Adam Taylor's profile photo
paolo de santis's profile photo
Josh Brown's profile photo
Education
  • Massachusetts Institute of Technology
    EE, 1978
Basic Information
Gender
Male
Story
Tagline
I'm interested in computers and science. I'm fascinated and horrified by strong beliefs not grounded in reality.
Introduction
Interested in 
  • Android development.
  • iOS development.
  • Science - especially quantum mechanics.
  • Java and its possible successors.
Work
Occupation
Software Engineer (Java, Parallel Computing, Graphics, Mobile)
Employment
  • Coherent Logix
    Software Engineer, present
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Previously
Forest Grove, oregon - Livingston, NJ - Newton, MA - New Haven, CT
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