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Mouhammad Fakhoury
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New method efficiently generates hydrogen from water

Washington State University researchers have found a way to more efficiently generate hydrogen from water—an important key to making clean energy more viable.

Read more : https://m.phys.org/news/2018-02-method-efficiently-hydrogen.html

WSU researchers have found a way to create large amounts of inexpensive nanofoam catalysts that can facilitate the generation of hydrogen on a large scale by splitting water molecules. Credit: Washington State University
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35 and we're just getting started. A look at where we were and where we're going from our co-founders, John Warnock and Chuck Geschke, and CEO Shantanu Narayen: https://adobe.ly/2jdL7L1
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Mystery of the gray ribbons

+Abdelaziz Nait Merzouk has done it yet again: he's created a mathematical work of art! This one is a traditional Islamic tiling pattern that flirts with the impossible... namely, 5-fold symmetry. See all the small green 5-pointed stars?

The most exciting feature is one you might not notice at first. It's the gray ribbons! Follow one with your eye and see where it goes. What does it do?

If you followed it forever, would it loop around back to where it started?

I don't know, so this makes a nice puzzle. Let's do it systematically.

In this picture you can see a lot of purple stars.

Puzzle 1. How many points does each purple star have?

Next to each purple star are a bunch of 5-pointed stars with light green points. I'll call these green stars.

There are also some more complicated things where two green stars overlap, sharing 2 points. I'll call these twin stars.

Puzzle 2. How many points of each purple star end in a green star?

Puzzle 3. How many points of each purple star end in a twin star?

If you look carefully, all the designs are formed by gray ribbons. And that's where things get really interesting. What happens to a gray ribbon as you follow it along? It's hard to say because the picture isn't big enough to see. But you can figure it out anyway.

When a gray ribbon goes through a green star an into a purple star, it turns either left or right and pops out.

Then the gray ribbon continues until it hits another purple star, and the story goes on. So we can keep track of its progress like this:

LRLRLLRLR....

... unless it hits a twin star!

When hits a twin star, it makes a slight turn either left or right. In this case let's write a lower-case "l" or "r". It then quickly reaches a purple star. It goes in, and as usual it turns either left or right and pops out.

So, we get a sequence sorta like this:

RRLRlRLRLLLRrRRLl....

I'm just making this one up, it probably ain't exactly right.

Puzzle 4. What's the pattern of this sequence?

I believe it's the same for every gray ribbon that hits a purple star. Some gray ribbons just go along straight lines, minding their own business. But let's ignore these.

Puzzle 5. If we follow a gray ribbon that hits a purple star for long enough, do we get back where we started?

For more of +Abdelaziz Nait Merzouk's tiling patterns, go here:

https://plus.google.com/u/0/114982179961753756261/posts/VdiBx4jz3U1

The twin stars look like 'defects', but they're inevitable. +Greg Egan and I explained the math here:

https://blogs.ams.org/visualinsight/2015/02/01/pentagon-decagon-packing/

#geometry
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"No two neurons are genetically alike." "The genetic makeup of any given brain cell differs from all others." "One question to be explored is whether genes associated with a brain disorder may harbor somatic mutations. The fact specific genes only explain a small proportion of cases may be because researchers have only been looking in the germ line (sex cells)." "Maybe the person doesn't have the mutation in their germ line, but some percentage of their neurons have it."

"Somatic mosaicism may also contribute to neural diversity in general. 'It might explain why everybody's different -- it's not all about the environment or genome. There's something else. As we understand more about somatic mosaicism, I think the contribution to individuality as well as the spectrum [of symptoms] you find in, for example, autism, will become clear."
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> At the core of the crash optimisation dilemma is a simple question: how do we allocate risk in society? In this instance the risk of dying in a car accident. We face many similar risk allocation decisions already. Complex systems of insurance and finance are set up with the explicit goal of spreading and reallocating these risks. We often allow people to purchase additional protection from risk through increased insurance premiums, and we sometimes allocate/gift people extra protections (e.g. certain politicians or leaders). Might we end up doing the same thing when it comes to the risk of being struck by a self-driving car? Liu asks us to imagine the following:

Immunity Device Thought Experiment: "It would not be implausible or unreasonable for the manufacturers of autonomous vehicles to issue what I would call here an “immunity device”: the bearer of such a device would become immune to collisions with autonomous vehicles. With the ubiquity of smart personal communication devices, it would not be difficult to develop a transmitting device to this end which signals the identity of its owner. Such an amulet would protect its owner in situations where an autonomous vehicle finds itself careening towards her, and would have the effect of deflecting the care away from that individual and thereby divert the car to engage in a new trolley problem style dilemma elsewhere." (Liu 2016, 169)

The thought experiment raises a few important and interesting questions. First, is such a device technically feasible? Second, should we allow for the creation of such a device? And third, if we did, how should we allocate the immunity it provides?

More: http://philosophicaldisquisitions.blogspot.com/2017/04/the-ethics-of-crash-optimisation.html
via Patrick Lin
The Ethics of Crash Optimisation Algorithms
The Ethics of Crash Optimisation Algorithms
philosophicaldisquisitions.blogspot.com
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