Later On

A blog written for those whose interests more or less match mine.

Archive for May 9th, 2018

Artificial Neural Nets Grow Brainlike Navigation Cells

leave a comment »

Evolution seems to find efficient solutions. John Rennie writes in Quanta:

Having the sense to take a shortcut, the most direct route from point A to point B, doesn’t sound like a very impressive test of intelligence. Yet according to a new report appearing today in Nature, in which researchers describe the performance of their new navigational artificial intelligence, the system’s ability to explore complex simulated environments and find the shortest route to a goal put it in a class previously reserved for humans and other living things.

The surprising key to the system’s performance was that while learning how to navigate, the neural net spontaneously developed the equivalent of “grid cells,” sets of brain cells that enable at least some mammals to track their location in space.

For neuroscientists, the new work seems to offer important clues about how grid cells in living brains make us better navigators. It also shows how neural nets could contribute greatly to future neuroscience studies: Neil Burgess, a cognitive neuroscientist at University College London who was not involved with the study, suggested that the systems should “provide fertile ground for understanding how and why the human brain works as it does.”

Meanwhile, for AI researchers, the work’s relevance to improving automated navigation systems is obvious. But its greater importance might eventually lie in suggesting a more general way to enhance the intelligence of machines.

According to the researchers Andrea Banino at the British AI company DeepMind and Caswell Barry at University College London, who were lead authors on the new Nature paper, the project evolved out of questions they had about the function of the brain’s grid cells. Grid cells are often called “the brain’s GPS” because of their importance to navigation in many animal species. (Edvard Moser and May-Britt Moser shared a 2014 Nobel Prize for their discovery of grid cells nine years earlier.) These clusters of neurons, which are arranged in roughly hexagonal arrays, collectively work like the inertial guidance systems on ships, aircraft and missiles: They keep track of how the body is moving through space, even in total darkness. “It’s basically updating your belief about where you are based on how you’re moving,” Barry said.

Neuroscientists have therefore credited grid cells with performing the function called “path integration” — the dead-reckoning form of navigation that doesn’t involve external cues: for example, “Take five steps forward, turn 90 degrees to the left, then walk straight ahead for another 15 steps.…” But various experiments have also hinted that grid cells perform other functions, including some that might go beyond navigation. For example, some studies implicate grid cells in measuring time and distance during travel. As Barry noted, if grid cells provide a spatial reference for objects and locations, “then in principle you can use them to calculate the direct route between those places” — that is, what’s called “vector-based navigation.”

The researchers decided to use deep-learning neural networks to investigate the role of grid cells in these navigational functions. As a first step, they set up a neural net to learn how to do path integration for a simulated agent moving through a small space. “We wanted to see whether we could set up an artificial network with an appropriate task so that it would actually develop grid cells,” Barry said.

The neural net obliged, and, according to Barry, “what was surprising was how well it worked.” The “grid units” that spontaneously emerged in the network were remarkably similar to what’s seen in animals’ brains, right down to the hexagonal grid.


The grid units that organized spontaneously in the neural network given a navigation task are surprisingly similar to the analogous grid cells in the brain, right down to their approximately hexagonal arrangement. These scans show firing activity in the living and artificial neurons.

The research team then joined the neural network’s abilities to systems that helped simulated agents find their way through mazelike virtual environments to goals. The system with grid units was far superior to systems without: For example, the system could tell if a previously closed door offered a shortcut to the goal, and it would take that route preferentially. According to Banino, this knack demonstrated that the grid units in the neural net were performing vector-based navigation because they were identifying a shorter, more direct route based on knowledge of the goal’s position.

“I think with this work, we were able to give a proof of principle that grid cells are used for taking shortcuts,” Banino said. The results therefore supported theories that grid cells in the brain are capable of both path integration and vector-based navigation. Comparable experimental proof with studies on living animals, he added, would be much more difficult to obtain.

“The interesting implication is that this same approach could be used for different sorts of neuroscience questions,” Barry said. Researchers interested in limb control, for example, could train a neural network to . . .

Continue reading.

Later in the article:

Francesco Savelli, a neuroscientist at Johns Hopkins University who co-authored a commentary accompanying the new Nature paper, offered a similar view. He considers it very interesting that “you somehow get these [grid] cells without programming them. … And still they come out, as emergent properties.”

Written by LeisureGuy

9 May 2018 at 7:39 pm

The big question about Trump that’s sitting in plain sight, unanswered

leave a comment »

Greg Sargent writes in the Washington Post:

Earlier today on “Morning Joe,” Mika Brzezinski raised the question of whether President Trump’s decision to pull out of the Iran nuclear deal was really an effort to “deflect” from other story lines — that is, from the many scandals now consuming the administration.

“Our allies are upset, for sure, at a time when I think the president’s sanity is being questioned globally,” Brzezinski said, adding that “the totality of this president’s behavior and decisions” raises the question of whether “he has the moral compass to make a decision based on our own national security even, at this point.”

This hints at a broader question, one that is sitting there right at the end of our noses: Is Trump capable of formulating — or operating in accordance with — any meaningful conception or vision of what is good for the country?

This question goes beyond the particulars of the Iran nuclear deal. On that front, you can read this Post editorial calmly demolishing the decision as a deeply reckless one that makes war more likely. Or you can read The Post fact-checking team’s comprehensive debunking of the lies and distortions that Trump himself offered in explaining the decision.

Or you can read this report saying Trump made the decision in part because he has instinctual faith in his ability to be a “disrupter on the world stage.” Or this one saying Trump is convinced he made the right call because it made the “eggheads” on CNN angry.

Even putting aside the Iran deal for now, other new developments this morning all point toward the question posed above:

• Trump just tweeted that it might be time to “take away credentials” from some news media. He cited a report claiming that “91% of the Network News about me is negative (Fake).” Trump explicitly defined all merely negative stories about him as “fake.” This is basically a declaration that the news media’s efforts to hold him accountable are inherently illegitimate, or at least are grounds for retributive action. Is Trump even capable of imagining that criticism of him flows from the crucial institutional role the press plays in our democracy? This sort of thing isn’t mere bluster: It has convinced a majority of Republicans that the press is the “enemy of the people.”

• The Post published a bombshell report claiming that the president might side with Rep. Devin Nunes (R-Calif.) in a dispute that could endanger an intelligence agent. Nunes is seeking documents from the Justice Department as part of his shadow effort to use Congress’s oversight machinery to create an alt-narrative giving Trump a pretext to shut down special counsel Robert S. Mueller III’s investigation, if he chooses. Intelligence officials protested that turning over the particular materials Nunes wants could put an agent at risk. To be fair, Trump has so far sided with them. But The Post reports that members of Trump’s own administrationworry that he will ultimately side with Nunes — putting an intelligence source at risk — possibly because he may end up convinced that the source provided material to the Mueller probe.

• The Senate Intelligence Committee just released a reportfinding that Russia waged an “unprecedented, coordinated cyber campaign” against the United States’ voting infrastructure. The larger context: Trump has failed to organize a strong response to future Russian electoral sabotage, because he is reluctant to acknowledge that it happened at all in 2016, as that would diminish the greatness of his victory. This puts Trump at odds with members of his own administration who regard the fact of Russian interference “as objective reality,” putting future elections at risk out of sheer megalomania.

Again and again and again, Trump has made decisions that are obviously not rooted in any meaningful effort to evaluate their substantive and moral complexities or potential consequences. The thinly veiled Muslim ban went forward despite two internal analyses undercutting the rationale that it was needed for national security. When Trump debated whether to cut refugee flows, the White House deep-sixed on deeply spurious grounds internal administration data that showed refugees are a net fiscal positive. Trump’s decision on tariffs was scandalously slapdash and haphazard, and reflected the fact that he was “gunning for a fight” after getting “unglued” over a spate of unflattering headlines.

Trump pardoned former Arizona sheriff Joe Arpaio, in a terrible display of contempt for the rule of law, after getting “sold on the pardon as a way of pleasing his political base.” When faced with a severe backlash over his failure to unambiguously condemn white supremacist violence in Charlottesville, he nonetheless felt “vindicated” because he sensed that his base would agree with him. The idea that he might have a responsibility to speak to the whole nation as a unifying voice at a searingly difficult national moment could not have been further from his mind. Indeed, doing the opposite was arguably the deliberate goal.

Again and again and again, independent reporting has revealed that when the decision-making rubber hits the road — that is, when the actual process kicks in of weighing pros and cons, and complexities and contingencies, and upsides and downsides for the country — other factors have intruded: Trump’s rage over something else. His desire to  . . .

Continue reading.

Written by LeisureGuy

9 May 2018 at 12:25 pm

Nice addition to lunch salad: Dulse

leave a comment »

I often have a salad for lunch. Today it was:

Dressing:

1.5 Tbsp pesto from Costco (3 WW points)
juice of 1/2 lemon
2 tsp Samal Oelek chili paste

Put into small jar and shake well.

Salad:

2 good handfuls baby kale and arugla (Costco again)
5 stalks asparagus, chopped
3 large scallions, chopped
1 yellow bell pepper, chopped
2 pickled eggs, sliced
2 oz. frozen diced avocado (3 WW points)
good piece of dulse, cut into smaller pieces with kitchen shears

The dulse adds a nice chewiness along with good flavor. Pickled eggs are also chewy, being pretty firm.

6 WW points total, which isn’t bad. Dinner tonight is steelhead trout, with 2 Tbsp olive oil (8 points total, 4 points apiece) and lemon slices, roasted on a baking sheet lined with nonstick foil for 30 minutes in a 300ºF oven. Zero points for the trout. After dinner we have a bowl of frozen berries, thawed: zero points. I favor mixed berries (blue, rasp, and black) and The Wife goes for wild blueberries.

Breakfast is my big meal: 9 points, from 2 Tbsp chia seed (3 points), 1/4 c pomegranate juice (2 points) and 1 Tbsp olive oil (4 points), in which I sauté a Serrano or Fresno pepper, a few stalks of asparagus, an ounce or two of oyster mushrooms, onion or a few scallions, and a few cherry tomatoes, with a over-easy egg on top.

So the total today is 19 points, with 24 currently allowed.

Written by LeisureGuy

9 May 2018 at 12:19 pm

Posted in Daily life, Food, Recipes

Why do people keep showering cash on Trump lawyer Michael Cohen?

leave a comment »

Paul Waldman writes in the Washington Post:

Michael Cohen, President Trump’s former “personal lawyer,” has had a remarkable career, by which I mostly mean that it’s remarkable that he hasn’t gone to jail yet. But the law is catching up to him, which may also mean that it’s catching up to the president.
Last night we got some new and tantalizing news, which I’m going to try to put in context.
I think the best way to understand it is this: When someone does business with Cohen, they may not be doing it for legitimate reasons. If you need a lawyer or some real estate advice and it’s all aboveboard, this is not the man you seek out. If you do, there will almost inevitably be something fishy going on. It might or might not be illegal, but it will definitely be sketchy in one way or another. And there are some interesting people doing business with Cohen.
Last night, Michael Avenatti, Stormy Daniels’s lawyer, went public with the results of an investigation he claimed provided details on transactions to and from Essential Consultants, the shell company Cohen set up in Delaware to pay Daniels $130,000 to keep quiet about the affair she says she had with President Trump. You’ll recall that Trump first denied that he knew anything about it, but then his lawyer Rudy Giuliani admitted that he reimbursed Cohen for the payoff.
Avenatti’s case has been deemed credible by multiple news organizations. The Post’s Philip Bump summarizes:

On Tuesday, Daniels’s current attorney, Michael Avenatti, released a document detailing a much more complex set of transactions involving the Essential Consultants account with First National Bank. In total, he alleged, more than $4 million passed through the account in 2017 and early this year, including payments from entities associated with major companies such as AT&T and the drug company Novartis. Most explosively, he claimed that Essential Consultants had received $500,000 from a company affiliated with the Russian oligarch Viktor Vekselberg.
Last week, the New York Times reported that Vekselberg had been detained and questioned by federal agents related to special counsel Robert Mueller’s probe earlier this year. Vekselberg attended Trump’s inauguration, as well as a December 2015 dinner in Moscow that was also attended by Russian President Vladimir Putin and former White House national security adviser Michael Flynn.
AT&T and Novartis acknowledged the payments, with the former describing Essential Consultants as being one of a series of firms hired to “provide insights into understanding the new administration.” An attorney for the firm Columbus Nova — the one associated with Vekselberg — told The Washington Post that the payments were for consulting work not related to the Russian or his business, Renova Group.

To my point that when you engage Cohen you’re doing something questionable, let’s begin with AT&T. As it happens, the company was seeking a multibillion-dollar merger with Time Warner that has to be approved by the federal government. Trump opposed the deal as a candidate, and his Justice Department has sued to stop it; the matter is currently before the courts.
AT&T already employs a small army of lawyers and lobbyists, and indeed, the company issued a statement saying Cohen “did no legal or lobbying work for us, and the contract ended in December 2017.” So they paid Cohen a few hundred thousand dollars for nothing but his “insights.” Might it be that the company saw dropping a heap of money on Cohen as a way to get an inside track to the president and win his goodwill?
What insights did Novartis want? Its biggest priority is probably to prevent the government from taking any action to reduce drug prices, as Trump has periodically claimed he wants to do. Novartis, which has been questioned about this by Mueller’s team, says it “entered into a one year agreement with Essential Consultants shortly after the election of President Trump focused on U.S. healthcare policy matters,” for which it paid Cohen a remarkable $1.2 million. Ah yes, it was seeking Cohen’s health-care expertise.
Another company, Korea Aerospace Industries Ltd, which is contending for a large Air Force contract, paid Cohen $150,000. It told The Post that “the payments were to provide legal consulting to assist in the company’s reorganization of its ‘internal accounting system’ and did not involve the Air Force deal or other lobbying.” Sure, that’s believable. Why wouldn’t a large foreign corporation hire Trump’s lawyer, who certainly isn’t an accountant, to help it reorganize its accounting system?
And what about the Russian oligarch? What was he seeking from Cohen? Columbus Nova told the Wall Street Journal that it “hired Michael Cohen as a business consultant regarding potential sources of capital and potential investments in real estate and other ventures.”
Boy, there sure are a lot of people eager to acquire Cohen’s brilliant insights. . .

Continue reading.

Written by LeisureGuy

9 May 2018 at 11:50 am

Gina Haspel would obey her broken moral compass

leave a comment »

Gina Haspel refused to answer Sen. Kamela Harris’s questions about whether the CIA/Bush torture program was “immoral.” So much for Ms. Haspel’s moral compass: it doesn’t provide her any direction. She also said that she believed that torture produced valuable intelligence (in stark contrast to the Senate investigation and also in contradiction to the findings of effective professional interrogators, who say that torture produces garbage—the person tortured will say anything s/he thinks her torturers want to hear—and the effective way to gain intelligence is through trust. And, of course, she cooperated in destroying the video evidence of the torture, thus obstructing justice.

Karoun Demirjian and Shane Harris report in the Washington Post:

Gina Haspel told members of the Senate Intelligence Committee on Wednesday that she “will not restart” a controversial CIA interrogation program if confirmed to lead the agency and that she would obey her moral compass, not President Trump, if she was ever instructed to carry out other questionable activities.
“We’re not getting back into that business,” Haspel said. “I would not restart, under any circumstances, an interrogation program at CIA.”
“My moral compass is strong,” Haspel said as the committee’s top Democrat, Sen. Mark R. Warner (Va.), pressed her to define her “moral code.”
“I would not allow CIA to undertake activity that is immoral, even if it is technically legal. I would absolutely not permit it,” Haspel continued. “I believe CIA must undertake activities that are consistent with American values.”
Haspel resisted efforts by senators to get her to say whether she believed it was morally wrong for her agency to use “enhanced” interrogation techniques on terrorist suspects, including waterboarding, which many have said is a form of torture. [So much for her “moral compass”: it didn’t even provide enough direction to answer the question. And since she apparently doesn’t view the program as morally wrong, she apparently would indeed restart it, despite her protestations. – LG] She said that the techniques had been authorized at the time by the highest legal authorities in the U.S. government and by President George W. Bush. [Her defense in the destruction of video evidence amounted to much the same thing: “I was just following orders.” – LG]
Senators were visibly frustrated at Haspel’s unwillingness to say definitively whether she believed it was wrong at the time to waterboard terrorist suspects. Haspel defended the interrogation sessions.
“We got valuable information from debriefing of al-Qaeda detainees,” she told Sen. Kamala D. Harris (D-Calif.). “I don’t think it’s knowable whether interrogation techniques played a role in that.”
Senators have asked several of Trump’s Cabinet nominees to commit to standing up to the president and informing Congress if he were to pressure them to do anything legally or morally questionable. But the pledge takes on extra significance with Haspel, whose hearing centered around the role she played in the CIA’s interrogation program — something Trump said on the campaign trail he wouldn’t mind bringing back into practice.
Haspel told senators that she doubted the president would ever ask her to waterboard a suspect [Trump has said he would do a lot worse than waterboarding – LG], stressing that experience had shown that the CIA “is not the right place to conduct interrogations,” as it does not have the proper expertise. . .

Continue reading.

Written by LeisureGuy

9 May 2018 at 10:42 am

Before you judge Trump

leave a comment »

Andy Slavitt makes a good point:

Before you judge…

Let he who has never sold access to a pharmaceutical company by having them buy off his blackmail payment to a porn star he silenced so he could illegally support his campaign after being caught bragging about sexual assault cast the first stone.

Written by LeisureGuy

9 May 2018 at 10:27 am

How the Father of Computer Science Decoded Nature’s Mysterious Patterns

leave a comment »

JoAnna Klein reports in the NY Times:

Many have heard of Alan Turing, the mathematician and logician who invented modern computing in 1935. They know Turing, the cryptologist who cracked the Nazi Enigma code, helped win World War II. And they remember Turing as a martyr for gay rights who, after being prosecuted and sentenced to chemical castration, committed suicide by eating an apple laced with cyanide in 1954.

But few have heard of Turing, the naturalist who explained patterns in nature with math. Nearly half a century after publishing his final paper in 1952, chemists and biological mathematicians came to appreciate the power of his late work to explain problems they were solving, like how zebrafish get their stripes or cheetahs get spots. And even now, scientists are finding new insights from Turing’s legacy.

Most recently, in a paper published Thursday in Science, chemical engineers in China used pattern generation described by Turing to explain a more efficient process for water desalination, which is increasingly being used to provide freshwater for drinking and irrigation in arid places.

Turing’s 1952 paper did not explicitly address the filtering of saltwater through membranes to produce freshwater. Instead, he used chemistry to explain how undifferentiated balls of cells generated form in organisms.

It’s unclear why this interested the early computer scientist, but Turing had told a friend that he wanted to defeat Argument From Design, the idea that for complex patterns to exist in nature, something supernatural, like God, had to create them.

A keen natural observer since childhood, Turing noticed that many plants contained clues that math might be involved. Some plant traits emerged as Fibonacci numbers. These were part of a series: Each number equals the sum of the two preceding numbers. Daisies, for example, had 34, 55 or 89 petals.

“He certainly was no militant atheist,” said Jonathan Swinton, a computational biologist and visiting professor at the University of Oxford who has researched Turing’s later work and life. “He just thought mathematics was very powerful, and you could use it to explain lots and lots of things — and you should try.”

And try, Turing did.

“He came up with a mathematical representation that allows form to emerge from blankness,” said Dr. Swinton.

In Turing’s model, two chemicals he called morphogens interacted on a blank arena. “Suppose you’ve got two of these, and one will make the skin of an animal go black and the skin of the animal go white,” explained Dr. Swinton. “If you just mix these things in an arena, what you get is a gray animal.”

But if something caused one chemical to diffuse, or spread, faster than the other, then each chemical could concentrate in evenly spaced localized spots, together forming black and white spots or stripes.

This is known as a “Turing instability,” and, the Chinese researchers who published the new paper determined that it could explain the way shapes emerged in salt-filtering membranes.

By creating three-dimensional Turing patterns like bubbles and tubes in membranes, the researchers increased their permeability, creating filters that could better separate salt from water than traditional ones.

“We can use one membrane to finish the work of two or three,” said . . .

Continue reading.

Written by LeisureGuy

9 May 2018 at 8:58 am

Posted in Daily life, Math, Science

%d bloggers like this: