Counterintuitive Physics Property Found To Be Widespread In Living Organisms (phys.org) 58
Lisa Zyga, writing for Phys.Org: Ever since the late 19th century, physicists have known about a counterintuitive property of some electric circuits called negative resistance. Typically, increasing the voltage in a circuit causes the electric current to increase as well. But under some conditions, increasing the voltage can cause the current to decrease instead. This basically means that pushing harder on the electric charges actually slows them down. Due to the relationship between current, voltage, and resistance, in these situations the resistance produces power rather than consuming it, resulting in a "negative resistance." Today, negative resistance devices have a wide variety of applications, such as in fluorescent lights and Gunn diodes, which are used in radar guns and automatic door openers, among other devices.
Most known examples of negative resistance occur in human-engineered devices rather than in nature. However, in a new study published in the New Journal of Physics, Gianmaria Falasco and coauthors from the University of Luxembourg have shown that an analogous property called negative differential response is actually a widespread phenomenon that is found in many biochemical reactions that occur in living organisms. They identify the property in several vital biochemical processes, such as enzyme activity, DNA replication, and ATP production. It seems that nature has used this property to optimize these processes and make living things operate more efficiently at the molecular scale. The researchers provided two examples of biological processes that have negative differential responses. The first example is substrate inhibition, which is a process used by enzymes to regulate their ability to catalyze chemical reactions: "When a single substrate molecule binds to an enzyme, the resulting enzyme-substrate complex decays into a product, generating a chemical current," writes Zyga. "On the other hand, when the substrate concentration is high, two substrate molecules may bind to an enzyme, and this double binding prevents the enzyme from producing more product. As an increase in substrate molecule concentration causes a decrease in the chemical current, this is a negative differential response."
The second example has to do with autocatalytic reactions -- "self-catalyzing" reactions, or reactions that produce products that catalyze the reaction itself: "Autocatalytic reactions occur throughout the body, such as in DNA replication and ATP production during glycolysis," writes Zyga. "The researchers showed that negative differential responses can arise when two autocatalytic reactions occur simultaneously in the presence of two different chemical concentrations (reservoirs) in an out-of-equilibrium system."
Most known examples of negative resistance occur in human-engineered devices rather than in nature. However, in a new study published in the New Journal of Physics, Gianmaria Falasco and coauthors from the University of Luxembourg have shown that an analogous property called negative differential response is actually a widespread phenomenon that is found in many biochemical reactions that occur in living organisms. They identify the property in several vital biochemical processes, such as enzyme activity, DNA replication, and ATP production. It seems that nature has used this property to optimize these processes and make living things operate more efficiently at the molecular scale. The researchers provided two examples of biological processes that have negative differential responses. The first example is substrate inhibition, which is a process used by enzymes to regulate their ability to catalyze chemical reactions: "When a single substrate molecule binds to an enzyme, the resulting enzyme-substrate complex decays into a product, generating a chemical current," writes Zyga. "On the other hand, when the substrate concentration is high, two substrate molecules may bind to an enzyme, and this double binding prevents the enzyme from producing more product. As an increase in substrate molecule concentration causes a decrease in the chemical current, this is a negative differential response."
The second example has to do with autocatalytic reactions -- "self-catalyzing" reactions, or reactions that produce products that catalyze the reaction itself: "Autocatalytic reactions occur throughout the body, such as in DNA replication and ATP production during glycolysis," writes Zyga. "The researchers showed that negative differential responses can arise when two autocatalytic reactions occur simultaneously in the presence of two different chemical concentrations (reservoirs) in an out-of-equilibrium system."
How is it counter-intuitive? (Score:5, Interesting)
Most modern devices show negative resistance, as they want constant power, regardless of the supply voltage.
Surely plenty of biological processes have the same requirement. Evolution often finds the same solutions to problems as human designers, but just takes a little longer.
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In facts the article is wrong while describing negative resistance.
Negative resistance means that the more current you draw from such "component" the higher the voltage gets.
Re: How is it counter-intuitive? (Score:2)
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The term may not be the best do generally describe the behavior but certainly you may draw current from some components, in facts I was thinking to power supplies.
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Re:How is it counter-intuitive? (Score:5, Insightful)
Maybe it's more about some (not all) physicists (or is it just physics 'journalists') being so arrogant that they think they know more about biology than biologists and being wrong.
Re:How is it counter-intuitive? (Score:4, Funny)
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Re: How is it counter-intuitive? (Score:3)
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Funny. Too bad my theistic evolution wins without any effort against your naturalistic one that will automatically and unquestionably eliminate you.
I'll toast you as I'm enjoying the selection advantages.
Re: How is it counter-intuitive? (Score:2)
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I can't define every relevant term for you to enable you to have an intelligent discussion, but "naturalism" has a particular meaning which is not the opposite "of unnatural". There is nothing "unnatural" about my views, not only is theism -vastly- more present in the "natural world", it is the mainstream viewpoint. I don't know why you bother to throw out a claim of them being "incredibly immoral" from nothing (probably the most your mind contains, considering), but go ahead, explain how you derive moral
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This is phenomenally easy to disprove. While lots of people claim to be believers due to peer pressure and having taken Pascal's wager, like you they try to avoid death despite their claim that eternal bliss awaits upon the event of their demise. This means of course that the accounting method is flawed in a way that counts a high very number despite the true total being close to zero.
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This is phenomenally easy to disprove. While lots of people claim to be believers due to peer pressure and having taken Pascal's wager, like you they try to avoid death despite their claim that eternal bliss awaits upon the event of their demise. This means of course that the accounting method is flawed in a way that counts a high very number despite the true total being close to zero.
Then "disprove" it. It is simple statistical fact. Stats [wikipedia.org]
Do you even try to have your very next inference believable even to yourself, or are you just a reality-denying lunatic? 2.4 billion people is not "close to zero", even if you have some absurd excuse as to why you dismiss reality. Sorry you don't understand Pascal's Wager and its implications either, as yet another cognitive impairment of yours, but contrary to the boilerplate atheist disingenuous rendering of it, it does not say theism is a fact b
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More obviously lying absurdity, that, naturally since you don't believe a word of it, neither do I.
You've lost every salient point, and will the next time as well, with any reasonably intelligent person you try to foist your absurdities off on.
But look on the bright side. You'll be gone soon and your entire life an ineffectual waste of the brain you were given.
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Amusing to the last. You have not the slightest start on "why we all know", because as your blatantly lying brain is fully clear on, you have been -logically refuted- on every point, your bizarre directly-proven false statistical claims of Christianity's following, your failed understanding of what "naturalism" is, your irrational rendering of an supposed issue with Pascal's wager, by rendering it as something it doesn't say ("this is thus proven true") instead of what it does say ("this is rational to fol
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I'm literally the only one of us that could possibly be considering it in an intellectually honest way, since I'm the only one willing to admit that I don't have an answer to everything. Lying and saying that you can offer an intellectually honest and rational answer by just going with "... and then a miracle happens 'cause my imaginary friend done says it's true" as your "answer" is pathetic. Now serio
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How is it "greater than the sum of it's parts"?
I think you don't understand either naturalism or supervenience in the context of naturalism.
To be scientific here, can you point to the parts that aren't among the parts?
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A blind system can still find solutions, it doesn't require conciousness - he used a figure of speech. Also you might want to read up on the Chinese Room.
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The Chinese Room is a silly argument. In the first place the proposed action is impossible in principle, and in the second place, even if it were true the argument would be that the system was intelligent, not any particular piece of it.
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Evolution "finds" nothing.
The entire of the Earth's biosphere would disagree.
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Doubling down?
The biosphere doesn't agree or disagree either, it's just the result of a designed biological factory.
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it's just the result of a designed biological factory.
Designed by who, or what?
Just because you feel a need to assume a "designer" doesn't mean there is one.
Of couse, it doesn't mean that there isn't one either.
There's just no evidence one way or the other.
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Sorry, you mean a modern SYSTEM such as a switching power supply. There is not a single component in there that BY ITSELF has negative resistance. Few devices have negative resistance as an intrinsic property. The tunnel diode is one of the few that comes to mind, the unijunction transistor is another one.
And sorry, "most modern devices" definitely DO NOT use these components!
Get a clue.
F E E D B A C K (Score:2)
Not negative resistance. Negative resistance is a manner of creating feedback. but Negative feedback is a more general concept. e.g. the slashdot karma system s just one wild ass example
physicists in biology (Score:1)
...passed many stages, from very useful, in very beginning, to the phylosophic useless bullshit like this.
Shamed to admit that I contributed to this type of nonsense physical contribution to biology in the 90s.
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You can't even spell "philosophic". And what about negative resistance is nonsense? Have you ever measured your own biologically closed electric circuit between the nose and mouth?
I measured mine, and it does measure a different resistance depending on the polarity of the meter.
But I guess like doctors, you've got the body all figured out, have you?
It is attitudes like yours, that smug superiority while being totally wrong, that makes me believe it is the biological "sciences" that are the ones spouting non
biologists are luddites (Score:2)
Biologists are luddites when it comes to accepting modern physics into their realm. (For example, it took biologists over 100 years to accept the role of the photoelectric effect in photosynthesis---something that physicists and chemists take for granted.) Hopefully, now that more physicists have taken the initiative to investigate biological phenomena in detail, biology will be brought into the 21st century.
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Yes, for some reason the people in the soft sciences like biology and medicine are really unable to grasp physics. They don't want to believe they are made of atoms, I guess.
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soft sciences like biology and medicine
Tell me about soft sciences at 4am in the children's hospital when you're explaining to parents who have been waiting in line with their sick child since 11pm that you're sending the kid home with only Tylenol. Next to that, solving some math and messing around with giant magnets seems like the easier path. Also - some of us LIKE physics and in my case - especially chemistry :)
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As you know - soft means less rigorous with regards to experimental evidence, not physically more taxing. Medicine and biology are still soft in that sense regardless or how hard implementing them may be.
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Re:biologists are luddites (Score:4, Interesting)
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Well, to be fair for many medical procedures you can't do a double-blind study.
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Can you show me where I said soft sciences don't have value? Your puffed-up ego seems a bit fragile there.
Oh, you are a doctor? Makes sense.
Can I give you a suggestion? Get over yourself.
You know who saves more lives than you? Plumbers. City garbage workers. Food inspectors.
Seriously. Get. Over. Yourself. You guys fuck up a lot too, I don't see you lot bringing that up too often.
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Amen!
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By the way, you can thank those people who were "solving math and messing around with giant magnets" the next time you send a patient for an MRI study. (You do know how an MRI works, don't you?)
You should have learned the "hard" sciences while you were in college---not while you are at work on a busy day. You may even be a better physician if you took the time and not been so ignorant.
Perhaps you should find a chemist or physicist and thank them for making your profession more successful and productive so
Mostly wrong (Score:5, Informative)
KInda wrong.
Negative resistance does not produce power.
It does not have a "wide variety" of applications:
The negative resistance in the old gas-filled fluorescent tubes is not a feature, it is a bug, requiring a lot of positive reactance in an expensive and heavy iron ballast to swamp out the negative resistance.
Gunn diodes are rather rare microwave devices.
TFA doesn't even mention the classic most popular negative resistance device, the tunnel diode.
The autocatalytic responses are examples of positive feedback, not "negative differential response"..
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Negative resistance does not produce power.
Well, it can. It depends. There's static resistance and differential resistance, and a quadrant map to indicate which combination will generate power, or consume power.
It does not have a "wide variety" of applications:
You're off your rocker, here.
Parametric amplifiers, thyristors, as you noted- tunnel diodes, gunn diodes, just to name a few.
Gunn diodes are rather rare microwave devices.
They're neither rare, nor a microwave device. They're simply a diode with a single junction type (P, IIRC) and a negative resistance.
A Gunn diode oscillator can generate microwaves, though.
Are they used primarily for
Produce Power? (Score:2)
> in these situations the resistance produces power rather than consuming it, resulting in a "negative resistance.
Rubbish.
Lots of devices exhibit negative resistance, but they don't produce any power.
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Negative resistance seems to be a junk construct to allow one to explain inductors/capacitors/gas tubes/diodes and other similar devices without attempting to explain what is really going on.
The whole idea and the wikipedia page is utter garbage, there are talk pages that reference it being junk science but whoever wrote the crap seemed to get it past everyone even those it is junk science.
The first example of negative resistance is about a gas discharge tube having negative resistance and producing power b
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Incompetent authorship (Score:2)
The Electric Arc as a Negative Resistance (Score:3)
The best example of a negative resistance of which I am aware is the electric arc. (Not the electric spark, which is a different phenomenon.) In the electric arc, as the current across the arc increases, the voltage across it decreases, which is the definition of negative resistance. Intuitively, this occurs because as more current passes through the arc, the width of the arc increases, so there are more parallel paths for current to flow, thereby reducing the resistance to current flow.
This negative resistance phenomenon was first encountered as a nuisance by those using the electric arc light [wikipedia.org] invented by Sir Humphry Davy in the early 19th Century. These lamps had a tendency to produce excessive audio noise, hissing and humming, which we now recognize today as being a side effect of their negative resistance -- uncontrolled audio oscillations. These oscillations were first harnessed [wikipedia.org] to practical use by William Duddell [wikipedia.org], who attached switchable resonant circuits to an arc and a keyboard, and demonstrated what was almost certainly the first music synthesizer -- and, in fact, one of the first electronic oscillators of any type.
By placing the arc in a hydrogen atmosphere, and placing a magnetic field perpendicular to the path of the arc, Valdemar Poulsen [wikipedia.org] was able to move the frequency of oscillation into the low radio-frequency range -- up to about 200 kHz. The rights to this invention were sold to Cyril Elwell [wikipedia.org], a Stanford University graduate, who founded what was to become the Federal Radiotelegraph Company [wikipedia.org] in Palo Alto, California, in 1909 (with financing from Stanford faculty and alumni) to manufacture radio transmitters using them. By the end of World War I, Federal was manufacturing transmitters capable of 1 MW (one million watts) of output power [wikipedia.org], using the arc negative resistance oscillator.
Federal is probably the most influential technology company you've never heard of:
--While developing a companion receiver for the arc transmitter in Federal's lab in Palo Alto, Lee DeForest invented his "Audion," the triode vacuum tube (valve), the first electronic tube capable of amplification.
--Peter V. Jensen and Edwin S. Pridham left Federal in 1911, and developed the “Magna Vox” (latin: “Great Voice”), a.k.a. the loudspeaker (first public demonstration: Golden Gate Park, San Francisco, Dec. 10, 1915), and formed the Magnavox Corporation in 1917. Jensen later formed Jensen Industries, now International Jensen, Inc. (IJI).
--The lead technologist at Federal from 1913 to 1919 (and designer of the megawatt arc transmitter) was Leonard Fuller [wikipedia.org]. In 1932 he was professor of electrical engineering and department chair at the University of California, Berkeley. A fellow professor, Ernest O. Lawrence [wikipedia.org], spoke to him one day about his need for very large magnet pole pieces for the third-generation 27-inch (69-cm) cyclotron he was developing. At the depth of the Great Depression, there was simply no money available at Berkeley to manufacture such a thing. As it happened, the end of World War I caused the scrapping of several uncompleted megawatt arc transmitters, and Fuller realized that the scrapped pole pieces of their magnets -- which weighed 80 tons (72,000 kg) -- would serve the purpose. They were rescued from a Palo Alto junkyard, which is how it came to be that the Federal Radiotelegraph Company played a critical part in the development of the cyclotron.