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Тема
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 Explanation of Epigenetics for Total Beginners
[re: Mod vege]
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| Автор |
Mod vege (старо куче) |
| Публикувано | 06.01.17 05:26 |
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Добра статия-синтез относно епигенетиката. Копирам и не по-малко интересните коментари под нея.
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In simplified terms, (the study of heritable changes in phenotype that does not involve changes in the underlying DNA sequence) is the study of biological mechanisms that will switch genes on and off. What does that mean? Well, if you are new to this whole thing, we first need a quick crash course in biochemistry and genetics:
- Cells are fundamental working units of every human being. All the instructions required to direct their activities are contained within the chemical deoxyribonucleic acid, also known as DNA.
- DNA from humans is made up of approximately 3 billion nucleotide bases. There are four fundamental types of bases that comprise DNA – adenine, cytosine, guanine, and thymine, commonly abbreviated as A, C, G, and T, respectively.
- The sequence, or the order, of the bases is what determines our life instructions. Interestingly enough, our DNA sequence is mostly similar to that of a chimpanzee. Only a fraction of distinctively different sequences makes us human.
- Within the 3 billion bases, there are about 20,000+ genes. Genes are specific sequences of bases that provide instructions on how to make important proteins – complex molecules that trigger various biological actions to carry out life functions.
Now that you understand genetics, let’s learn about epigenetics. Epigenetics, essentially, affects how genes are read by cells, and subsequently how they produce proteins. Here are a few important points about epigenetics:
- Epigenetics Controls Genes. Certain circumstances in life can cause genes to be silenced or expressed over time. In other words, they can be turned off (becoming dormant) or turned on (becoming active).
- Epigenetics Is Everywhere. What you eat, where you live, who you interact with, when you sleep, how you exercise, even aging – all of these can eventually cause chemical modifications around the genes that will turn those genes on or off over time. Additionally, in certain diseases such as cancer or Alzheimer’s, various genes will be switched into the opposite state, away from the normal/healthy state.
- Epigenetics Makes Us Unique. Even though we are all human, why do some of us have blonde hair or darker skin? Why do some of us hate the taste of mushrooms or eggplants? Why are some of us more sociable than others? The different combinations of genes that are turned on or off is what makes each one of us unique. Furthermore, there have been indications that some epigenetic changes can be inherited.
- Epigenetics Is Reversible. With 20,000+ genes, what will be the result of the different combinations of genes being turned on or off? The possible permutations are enormous! But if we could map every single cause and effect of the different combinations, and if we could reverse the gene’s state to keep the good while eliminating the bad… then we could theoretically* cure cancer, slow aging, stop obesity, and so much more.
Here’s an analogy that might further help you to understand epigenetics. Think of the human life span as a very long movie. The cells would be the actors and actresses, essential units that make up the movie. DNA, in turn, would be the script — instructions for all the participants of the movie to perform their roles. Subsequently, the DNA sequence would be the words on the script, and certain blocks of these words that instruct key actions or events to take place would be the genes. The concept of genetics would be like screenwriting. Follow the analogy so far? Good. The concept of epigenetics, then, would be like directing. The script can be the same, but the director can choose to eliminate certain scenes or dialogue, altering the movie for better or worse. After all, Steven Spielberg’s finished product would be drastically different than Woody Allen’s for the same movie script, wouldn’t it?
* Editor’s Note: Be wary of self-help claims that exploit epigenetics and seem too good to be true. We recommend you read about the abuse of .
Ready to learn epigenetics in further detail? Read on:
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Comments
Gary Camp • 4 months ago
It is still not at all clear to me how information can be passed on from generation to generation (like in the recent article on Heart Attacks, "Memory of a heart attack is stored in our genes"). To be passed on there must be a change to the fertilized egg (or at least the growing baby organism). How is this accomplished?
mastercytosine Mod Gary Camp • 4 months ago
Hi Gary! Glad to see your interest in epigenetics! Reproductive cells (eggs and sperm) contain intact genetic information. During the reproductive process, the epigenetic tags are erased through what is known as "reprogramming" so that they can be re-programmed into specialized cells (blood, hair, etc). However, in mammals, about 1% of genes bypass this reprogramming process and end up with epigenetic tags being passed down, also known as epigenetic imprinting! Take this with a grain of salt though as epigenetic changes rapidly occur (relatively speaking) and it is difficult to prove whether they were inherited or induced by environmental changes again.
Carl • 10 months ago
Assuming 3 billion base pairs (correct) and about 99% nucleotide base pair correspondence between chimpanzees and human beings (incorrect- it is now around 96% and it depends on the size of nucleotide strands and how they're lined up, either human to chimpanzee or chimpanzee to human, but that's another story), approximately 1% of 3 billion is 30 million (based on your numbers), so where on earth do you get 15 million base pairs that differ!? I know-you maintain less than 1%, but that is just plain false. Furthermore, utilizing the assumed correct 96% base nucleotide correspondence, the number of different bases is actually 120 million, four times more than the previous number i mentioned mentioned, and more than 10 times the difference you stated in your article. Ugh! Get your facts straight and your numbers will follow!
John Doe Carl • 22 days ago
You are the coolest person alive.
mastercytosine Mod Carl • 10 months ago
Hi Carl. Thanks for pointing these numbers out! These figures have always debated on and have frequently changed over the years. Since there are many ways to interpret the count, we have decided to edit out the actual numbers in its entirety as they serve no purpose within the context of this article to convey the point (which is that a small amount of sequences can have great impact). Thanks for reading WhatisEpigenetics.com!
John Doe mastercytosine • 22 days ago
You could just say Carl was right and you were wrong
Carl • 10 months ago
Correction-not enough trimmethylxanthine today. 8 Exactly 8 times more than the number you stated.
Carl • 10 months ago
To clarify, I'm talking about haploid, not diploid (6 billion nucleotides), because it is assumed that bases will correspond as base pairs. So my writing here wss not clear and should state "bases" rather than base pairs. Also, there is more research out there demonstrating that humans and chimpanzees do not even have the 96% base correspondence claimed, especially when the Y chromosome is examined. Do we understand more or less of the human genotype? Definitely less. No one in the field of genetics would argue that fact. Now geneticists are saying that it will take hundreds of years to map out the real correspondences and causal relationships, when functioning and non functioning DNA are taken into consideration, and when the unsearchable complexity of this amazing (euphemism) self-replicating, self regulating, self-correcting living informational system is given it's proper reverence and humility (neither come easy to human being, me included here). So easy on the "we're just like chimpanzees" except for a few Lego pieces nonsense. When a chimpanzee can fly a 747 then I'll relent in my opinion. Better yet, give a chimpanzee your tax return to complete and then send the results to the IRS! Errant nonsense!!
Редактирано от Mod vege на 06.01.17 05:28.
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Тема
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 Самодостатъчните села Regen
[re: Mod vege]
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| Автор |
Mod vege (старо куче) |
| Публикувано | 18.01.17 01:39 |
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През лятото, което се задава, трябва да започне изграждането на изцяло самодостатъчните села ReGen – общности, които сами произвеждат всичките си хранителни ресурси и енергия. Датската архитектурна фирма EFFEKT се е заела с реализацията на дръзкия проект, за да докаже, че е напълно реалистично да се живее в общности, които са напълно независими и самодостатъчни във всички отношения.
Пет принципа определят селата Regen:
- енергийно позитивни домове,
- органична храна, произведена на място,
- енергия от чисти, възобновяеми източници, и нейното съхранение,
- рециклиране на водата и на отпадъците,
- овластяване на местните общности.
Домовете в общностите ще са напълно годни за устойчив начин на живот. Те ще се електрозахранват от фотоволтаични слънчеви панели. Пасивни пасивни отоплителни и охлаждащи системи ще елиминират натиска върху потреблението на електроенергия във всяка къща. Семействата ще отглеждат сами зсвоите собствени зеленчуци и плодове в общностни оранжерии. Заедно къщите ще образуват „споделена местна еко-система“.
Селищата ще имат по няколко обществени площада, които ще са оборудвани със станции за зареждане на електрически коли. Ще има и вертикални аквапонни земеделски площи.
Общността ще разчита много на съоръжения за съхранение на водните ресурси, както и на системи за рециклиране и превръщане на отпадъците в суровини. Заедно с това ще има зони за животновъдство, площадки за игра за децата, образователни центрове – всичко, от което есна общност се нуждае за своето развитите.
Първото село Regen е планирано за изграждане в Нидерландия това лято. Подготвят се и пилотни проекти в Швеция, Германия, Норвегия и Дания, а планове – макар и на ранен етап – има още за Китай, Африка, Обединените арабски емирства.
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Тема
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 Re: Самодостатъчните села Regen
[re: Mod vege]
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| Автор |
| (>[2] /dev/null) |
| Публикувано | 18.01.17 05:31 |
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Материалите за фотоволтаичните панели откъде точно ще ги вземат? И тях ли сами ще си ги произведат? :)
The last good thing written in C was Franz Schubert's Symphony No. 9.
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Тема
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Re: Самодостатъчните села Regen
[re: |]
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| Автор |
Mod vege (старо куче) |
| Публикувано | 19.01.17 01:02 |
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Независими и автономни не значи прекъснали връзката с останалия свят.
А дори ако се развият такива общности до големи селища и по-нататък, според мен може и сами да си ги произвеждат. Но това е далечно бъдеще.
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Тема
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Re: Самодостатъчните села Regen
[re: Mod vege]
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| Автор |
| (>[2] /dev/null) |
| Публикувано | 19.01.17 15:47 |
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Независими означава да могат да построят втора такава общност използвайки само продуктите които произвеждат. В противен случай е интелектуална маструбация на богати безделници.
The last good thing written in C was Franz Schubert's Symphony No. 9.
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Тема
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По скоро далавера на богатите им татковци
[re: |]
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| Автор |
~@!$^%*amp;()_+ (целия горен ред) |
| Публикувано | 22.01.17 19:39 |
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Тема
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Колко вредни са пластмасовите бутилки
[re: Mod vege]
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| Автор |
Mod vege (старо куче) |
| Публикувано | 27.01.17 05:12 |
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Cигypнo мaлĸo oт Bac знaят или ce интepecyвaт oт видa плacтмaca, oт ĸoятo ca нaпpaвeни бyтилĸитe и oт ĸoитo вceĸиднeвнo ĸoнcyмиpaмe вoдa и дpyги нaпитĸи. Toвa e изĸлючитeлнo вaжнo, тъй ĸaтo мaтepиaлът oпpeдeля дaли дaдeнa бyтилĸa мoжe дa ce изпoлзвa caмo вeднъж или e пoдxoдящa зa мнoгoĸpaтнa yпoтpeбa. Bcичĸи плacтмacoви бyтилĸи в тъpгoвcĸaтa мpeжa имaт зaдължитeлнa мapĸиpoвĸa, ĸoятo мoжe дa ни opиeнтиpa зaтoвa, дaли мaтepиaлът имa cĸлoннocт дa ocвoбoждaвa xимиĸaли в cъxpaнявaнaтa тeчнocт:
РЕТ или РЕТЕ
Oзнaчeнитe c тoзи знaĸ бyтилĸи ca eдинcтвeнo зa eднoĸpaтнa yпoтpeбa. Πpи пoвтopнo изпoлзвaнe имa вepoятнocт плacтмacaтa дa ocвoбoди тeжĸи мeтaли, ĸaĸтo и вeщecтвa, ĸoитo cъздaвaт xopмoнaлeн диcбaлaнc в opгaнизмa нa чoвeĸa. Bъпpeĸи тaзи oпacнocт, тoвa e нaй-чecтo изпoлзвaният тип плacтмaca зa пpoизвoдcтвo нa бyтилĸи. Имeннo зaтoвa e вaжнo тaĸъв тип oпaĸoвĸи дa ce изпoлзвaт caмo eднoĸpaтнo, cлeд ĸoeтo дa бъдaт изxвъpлeни в пoдxoдящитe ĸoнтeйнepи зa peциĸлиpaнe. C пoвтopнoтo изпoлзвaнe нa бyтилĸa cъc cимвoлa РЕТ или РЕТЕ, чoвeĸ тpябвa дa e гoтoв, чe e вepoятнo дa пpиeмe oгpoмнo ĸoличecтвo aлĸaлни eлeмeнти и бaĸтepии, ĸoитo ce ocвoбoждaвaт oт плacтмacaтa.
НDР или НDРЕ
Πлacтмacaтa, мapĸиpaнa c тoзи знaĸ нe oтдeля ниĸaĸви зaмъpcитeли. Πpeпopъчитeлнo e дa ce пиe вoдa oт бyтилĸи, пpoизвeдeни имeннo oт тaĸaвa плacтмaca. Toвa e eĸoлoгичнo чиcт мaтepиaл, ĸoйтo ce пpepaбoтвa изцялo. Kъм днeшнa дaтa в бyтилĸи oт НDР или НDРЕ ce cъxpaнявaт мляĸo и xpaни зa дeцa. Oт тoзи мaтepиaл ca и няĸoи дeтcĸи игpaчĸи, oпaĸoвĸи нa миeщи пpeпapaти, ĸaĸтo и oпpeдeлeни видoвe плacтмacoви тopбичĸи.
РVС или V
Изpaбoтeнитe oт тoзи вид плacтмaca oпaĸoвĸи oтдeлят мaлĸo ĸoличecтвo, нo вpeдни вeщecтвa oт 2 oпacни xимиĸaлa. И двeтe cъeдинeния имaт нeгaтивнo въздeйcтвиe въpxy бaлaнca oт xopмoни в opгaнизмa. Бyтилĸитe oт РVС ca мeĸи, гъвĸaви и нaй-oбиĸнoвeнo ce изпoлзвaт зa oпaĸoвaнe нa oлиo, зexтини и дpyги видoвe мacлa. He e изĸлючeнo в тъpгoвcĸaтa мpeжa дa ce cpeщнaт и дeтcĸи игpaчĸи, пpoизвeдeни oт тoзи вид плacтмaca. Peдицa пoтpeбитeлcĸи cтoĸи cъщo cпaдaт в тaзи гpyпa ĸaтo ĸaбeли, тpъби, BиK чacти, мapĸyчи и дpyги.
LDРЕ
Toвa e мapĸиpoвĸa, ĸoятo нaй-чecтo ce cpeщa пpи бyтилĸитe, cъxpaнявaщи вoдa, тъй ĸaтo плacтмacaтa нe ocвoбoждaвa вpeдни xимичecĸи вeщecтвa във пoмecтeнaтa тeчнocт. Baжнo e дa ce пoмни, чe тoзи тип мaтepиaл e бeзoпaceн caмo aĸo бъдe изпoлзвaн зa cъxpaнeниe нa вoдa. Πpи cъxpaнeниeтo нa вcяĸaĸъв дpyг вид тeчнocти или xpaни, плacтмacaтa мoжe дa oтдeли мнoгo oпacни зa cъpцeтo и ĸpъвoнocнaтa cиcтeмa нa чoвeĸ xимиĸaли.
РР
Toвa e бялaтa плacтмaca – пoлипpoпилeн. B пoвeчeтo cлyчaи e пoлyпpoзpaчнa. Упoтepбaтa й e cъcpeдoтoчeнa в oпaĸoвaнeтo нa мляĸo и paзлични видoвe cиpoпи. Πpи нaгpявaнe нe ce тoпи. Toвa e мaтepиaл, oтнocитeлнo бeзoпaceн щo ce ĸacae дo oтдeлянe нa вpeдни вeщecтвa.
РЅ
Eвтинaтa, лeĸa и издpъжливa плacтмaca – пoлиcтиpoл – нe e пoдxoдящa зa cъxpaнeниe нa тoпли xpaни и нaпитĸи. Haпyĸ нa дoĸaзaнaтa oпacнocт, тoчнo тoзи тип мaтepиaл ce изпoлзвa пpи изpaбoтĸaтa нa чaши зa ĸaфe или ĸyтии зa cъxpaнeниe нa xpaнa. Aĸo вce пaĸ ce нaлaгa дa бъдaт изпoлзвaни чaши или oпaĸoвъчни пpoдyĸти oт тaĸaвa плacтмaca e вaжнo дa ce пoмни, чe изoбщo нe бивa дa ce нaгpявaт, a cъxpaнявaнитe xpaни и нaпитĸи тpябвa дa ce пocтaвят cтyдeни.
РС или плacтмaca бeз пocoчeни cпeциaлни знaци
Toвa e нaй-oпacният вид плacтмaca. Tя oтнoвo ce cpeщa пpи бyтилиpaнe нa вoдa или oпaĸoвĸи зa xpaнa. Πлacтмacaтa, c oзнaчeниe РС или липcвaщo тaĸoвa, oтдeля биcфeнoл A. Toвa e вeщecтвo, ĸoeтo cпocoбcтвa paзpyшaвaнeтo нa eндoĸpиннaтa cиcтeмa в opгaнизмa. Oтдeлнo oт тoвa биcфeнoл A пoтиcĸa oбpaзyвaнeтo нa ecтpoгeн и дpyги xopмoни.
Cпeциaлиcтитe cъвeтвaт пpи възмoжнocт зa избop дa нacoчвaмe внимaниeтo cи ĸъм oбoзнaчитeлнитe знaци въpxy плacтмacoвитe издeлия и пpeпopъчвaт ĸoнcyмaциятa нa xpaни и нaпитĸи, ĸoитo ca cъxpaнeни в cтъĸлeнa бyтилĸa/oпaĸoвĸa.
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Тема
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Can Quantum Physics Explain Consciousness?
[re: Mod vege]
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| Автор |
Mod vege (старо куче) |
| Публикувано | 09.02.17 07:57 |
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?
NOV 7, 2016
A new approach to a once-farfetched theory is making it plausible that the brain functions like a quantum computer.
The mere mention of “quantum consciousness” makes most physicists cringe, as the phrase seems to evoke the vague, insipid musings of a New Age guru. But if a new hypothesis proves to be correct, quantum effects might indeed play some role in human cognition. , a physicist at the University of California, Santa Barbara, raised eyebrows late last year when he in Annals of Physics proposing that the nuclear spins of phosphorus atoms could serve as rudimentary “qubits” in the brain—which would essentially enable the brain to function like a quantum computer.
As recently as 10 years ago, Fisher’s hypothesis would have been dismissed by many as nonsense. Physicists have been burned by this sort of thing before, most notably in 1989, when Roger Penrose proposed that mysterious protein structures called “microtubules” played a role in human consciousness by exploiting quantum effects. Few researchers believe such a hypothesis plausible. Patricia Churchland, a neurophilosopher at the University of California, San Diego, memorably that one might as well invoke “pixie dust in the synapses” to explain human cognition.
Fisher’s hypothesis faces the same daunting obstacle that has plagued microtubules: a phenomenon called quantum decoherence. To build an operating quantum computer, you need to connect qubits—quantum bits of information—in a process called entanglement. But entangled qubits exist in a fragile state. They must be carefully shielded from any noise in the surrounding environment. Just one photon bumping into your qubit would be enough to make the entire system “decohere,” destroying the entanglement and wiping out the quantum properties of the system. It’s challenging enough to do quantum processing in a carefully controlled laboratory environment, never mind the warm, wet, complicated mess that is human biology, where maintaining coherence for sufficiently long periods of time is well nigh impossible.
Over the past decade, however, growing evidence suggests that certain biological systems might employ quantum mechanics. In photosynthesis, for example, help . Scientists have also that migratory birds have a “quantum compass” enabling them to exploit Earth’s magnetic fields for navigation, or that the human sense of smell could be rooted in quantum mechanics.
Fisher’s notion of quantum processing in the brain broadly fits into this emerging field of quantum biology. Call it quantum neuroscience. He has developed a complicated hypothesis, incorporating nuclear and quantum physics, organic chemistry, neuroscience and biology. While his ideas have met with plenty of justifiable skepticism, some researchers are starting to pay attention. “Those who read his paper (as I hope many will) are bound to conclude: This old guy’s not so crazy,” , a physicist at the California Institute of Technology, after Fisher gave a talk there. “He may be on to something. At least he’s raising some very interesting questions.”
Matthew Fisher has proposed a way for quantum effects to influence the workings of the brain. (Courtesy of Matthew Fisher)
, a physicist at the Massachusetts Institute of Technology and Fisher’s longtime friend and colleague, is skeptical, but he thinks that Fisher has rephrased the central question—is quantum processing happening in the brain?—in such a way that it lays out a road map to test the hypothesis rigorously. “The general assumption has been that of course there is no quantum information processing that’s possible in the brain,” Todadri said. “He makes the case that there’s precisely one loophole. So the next step is to see if that loophole can be closed.” Indeed, Fisher has begun to bring together a team to do laboratory tests to answer this question once and for all.
* * *
Fisher belongs to something of a physics dynasty: His father, , is a prominent physicist at the University of Maryland, College Park, whose work in statistical physics has garnered numerous honors and awards over the course of his career. His brother, , is an applied physicist at Stanford University who specializes in evolutionary dynamics. Matthew Fisher has followed in their footsteps, carving out a highly successful physics career. He shared the prestigious in 2015 for his research on quantum phase transitions.
So what drove him to move away from mainstream physics and toward the controversial and notoriously messy interface of biology, chemistry, neuroscience and quantum physics? His own struggles with clinical depression.
Fisher vividly remembers that February 1986 day when he woke up feeling numb and jet-lagged, as if he hadn’t slept in a week. “I felt like I had been drugged,” he said. Extra sleep didn’t help. Adjusting his diet and exercise regime proved futile, and blood tests showed nothing amiss. But his condition persisted for two full years. “It felt like a migraine headache over my entire body every waking minute,” he said. It got so bad he contemplated suicide, although the birth of his first daughter gave him a reason to keep fighting through the fog of depression.
Eventually he found a psychiatrist who prescribed a tricyclic antidepressant, and within three weeks his mental state started to lift. “The metaphorical fog that had so enshrouded me that I couldn’t even see the sun—that cloud was a little less dense, and I saw there was a light behind it,” Fisher said. Within nine months he felt reborn, despite some significant side effects from the medication, including soaring blood pressure. He later switched to Prozac and has continuously monitored and tweaked his specific drug regimen ever since.
His experience convinced him that the drugs worked. But Fisher was surprised to discover that neuroscientists understand little about the precise mechanisms behind how they work. That aroused his curiosity, and given his expertise in quantum mechanics, he found himself pondering the possibility of quantum processing in the brain. Five years ago he threw himself into learning more about the subject, drawing on his own experience with antidepressants as a starting point.
Since nearly all psychiatric medications are complicated molecules, he focused on one of the most simple, lithium, which is just one atom—a spherical cow, so to speak, that would be an easier model to study than Prozac, for instance. The analogy is particularly appropriate because a lithium atom is a sphere of electrons surrounding the nucleus, Fisher said. He zeroed in on the fact that the lithium available by prescription from your local pharmacy is mostly a common isotope called lithium-7. Would a different isotope, like the much more rare lithium-6, produce the same results? In theory it should, since the two isotopes are chemically identical. They differ only in the number of neutrons in the nucleus.
When Fisher searched the literature, he found that an experiment comparing the effects of lithium-6 and lithium-7 had been done. In 1986, scientists at Cornell University on the behavior of rats. Pregnant rats were separated into three groups: One group was given lithium-7, one group was given the isotope lithium-6, and the third served as the control group. Once the pups were born, the mother rats that received lithium-6 showed much stronger maternal behaviors, such as grooming, nursing and nest-building, than the rats in either the lithium-7 or control groups.
This floored Fisher. Not only should the chemistry of the two isotopes be the same, the slight difference in atomic mass largely washes out in the watery environment of the body. So what could account for the differences in behavior those researchers observed?
Fisher believes the secret might lie in the nuclear spin, which is a quantum property that affects how long each atom can remain coherent—that is, isolated from its environment. The lower the spin, the less the nucleus interacts with electric and magnetic fields, and the less quickly it decoheres.
Because lithium-7 and lithium-6 have different numbers of neutrons, they also have different spins. As a result, lithium-7 decoheres too quickly for the purposes of quantum cognition, while lithium-6 can remain entangled longer.
(Lucy Reading-Ikkanda for Quanta Magazine)
Fisher had found two substances, alike in all important respects save for quantum spin, and found that they could have very different effects on behavior. For Fisher, this was a tantalizing hint that quantum processes might indeed play a functional role in cognitive processing.
* * *
That said, going from an intriguing hypothesis to actually demonstrating that quantum processing plays a role in the brain is a daunting challenge. The brain would need some mechanism for storing quantum information in qubits for sufficiently long times. There must be a mechanism for entangling multiple qubits, and that entanglement must then have some chemically feasible means of influencing how neurons fire in some way. There must also be some means of transporting quantum information stored in the qubits throughout the brain.
This is a tall order. Over the course of his five-year quest, Fisher has identified just one credible candidate for storing quantum information in the brain: phosphorus atoms, which are the only common biological element other than hydrogen with a spin of one-half, a low number that makes possible longer coherence times. Phosphorus can’t make a stable qubit on its own, but its coherence time can be extended further, according to Fisher, if you bind phosphorus with calcium ions to form clusters.
In 1975, Aaron Posner, a Cornell University scientist, an odd clustering of calcium and phosphorous atoms in his X-rays of bone. He made drawings of the structure of those clusters: nine calcium atoms and six phosphorous atoms, later called “Posner molecules” in his honor. The clusters popped up again in the 2000s, when scientists simulating bone growth in artificial fluid them floating in the fluid. Subsequent experiments found
That’s the big picture scenario, but the devil is in the details that Fisher has spent the past few years hammering out. The process starts in the cell with a chemical compound called pyrophosphate. It is made of two phosphates bonded together—each composed of a phosphorus atom surrounded by multiple oxygen atoms with zero spin. The interaction between the spins of the phosphates causes them to become entangled. They can pair up in four different ways: Three of the configurations add up to a total spin of one (a “triplet” state that is only weakly entangled), but the fourth possibility produces a zero spin, or “singlet” state of maximum entanglement, which is crucial for quantum computing.
Next, enzymes break apart the entangled phosphates into two free phosphate ions. Crucially, these remain entangled even as they move apart. This process happens much more quickly, Fisher argues, with the singlet state. These ions can then combine in turn with calcium ions and oxygen atoms to become Posner molecules. Neither the calcium nor the oxygen atoms have a nuclear spin, preserving the one-half total spin crucial for lengthening coherence times. So those clusters protect the entangled pairs from outside interference so that they can maintain coherence for much longer periods of time—Fisher roughly estimates it might last for hours, days or even weeks.
In this way, the entanglement can be distributed over fairly long distances in the brain, influencing the release of neurotransmitters and the firing of synapses between neurons—spooky action at work in the brain.
* * *
Researchers who work in quantum biology are cautiously intrigued by Fisher’s proposal. , a physicist at University College London who has worked on quantum photosynthesis, calls it “a well-thought hypothesis. It doesn’t give answers, it opens questions that might then lead to how we could test particular steps in the hypothesis.”
The University of Oxford chemist , who investigates whether migratory birds’ navigational systems make use of quantum effects, concurs. “Here’s a theoretical physicist who is proposing specific molecules, specific mechanics, all the way through to how this could affect brain activity,” he said. “That opens up the possibility of experimental testing.”
Experimental testing is precisely what Fisher is now trying to do. He just spent a sabbatical at Stanford University working with researchers there to replicate the 1986 study with pregnant rats. He acknowledged the preliminary results were disappointing, in that the data didn’t provide much information, but thinks if it’s repeated with a protocol closer to the original 1986 experiment, the results might be more conclusive.
Fisher has applied for funding to conduct further in-depth quantum chemistry experiments. He has cobbled together a small group of scientists from various disciplines at UCSB and the University of California, San Francisco, as collaborators. First and foremost, he would like to investigate whether calcium phosphate really does form stable Posner molecules, and whether the phosphorus nuclear spins of these molecules can be entangled for sufficiently long periods of time.
Even Hore and Olaya-Castro are skeptical of the latter, particularly Fisher’s rough estimate that the coherence could last a day or more. “I think it’s very unlikely, to be honest,” Olaya-Castro said. “The longest time scale relevant for the biochemical activity that’s happening here is the scale of seconds, and that’s too long.” (Neurons can store information for microseconds.) Hore calls the prospect “remote,” pegging the limit at one second at best. “That doesn’t invalidate the whole idea, but I think he would need a different molecule to get long coherence times,” he said. “I don’t think the Posner molecule is it. But I’m looking forward to hearing how it goes.”
Others see no need to invoke quantum processing to explain brain function. “The evidence is building up that we can explain everything interesting about the mind in terms of interactions of neurons,” said , a neurophilosopher at the University of Waterloo in Ontario, Canada, to New Scientist. (Thagard declined our request to comment further.)
Plenty of other aspects of Fisher’s hypothesis also require deeper examination, and he hopes to be able to conduct the experiments to do so. Is the Posner molecule’s structure symmetrical? And how isolated are the nuclear spins?
Most important, what if all those experiments ultimately prove his hypothesis wrong? It might be time to give up on the notion of quantum cognition altogether. “I believe that if phosphorus nuclear spin is not being used for quantum processing, then quantum mechanics is not operative in longtime scales in cognition,” Fisher said. “Ruling that out is important scientifically. It would be good for science to know.”
____________
This post appears courtesy of .
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Тема
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Минер. вода в България – къде, коя, какво лекува ?
[re: Mod vege]
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| Автор |
Mod vege (старо куче) |
| Публикувано | 09.02.17 08:16 |
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България е надарена с минерални води, които помагат при почти всички болести. Само от болежката зависи дали тя ще се пие или ще поливате кожата си с нея. Единственото, което трябва да се знае е коя вода какво лекува.
Съставът на минералната вода в България може да ни помогне да се отървем от излишните килограми, но в същото време и за да зарасне по-бързо счупена кост. Лекарите съветват да се пие на малки глътки, за да не предизвикаме обратен ефект.
Банкя
Градът е разположен в красива котловина в подножието на северните склонове на Люлин планина, едва на 17 км от София, той е обявен за екологичен резерват. От единното хидротермално находище бликат няколко естествени и сондажни хидротермални източника, с температура на водата 36,5° С–37° С и общ дебит 24 л/сек. Всички тези хидротермални води са с ниска минерализация, хидрокарбонатно-сулфатно-натриеви, с ниска водна твърдост, бистри, безцветни, без мирис и с много приятни питейно-вкусови качества.
Какво лекува минералната вода в Банкя?
Подходящи са за лечение на сърдечно-съдови заболявания, смущения на нервната система, нарушения в обмяната на веществата.
Велинград
Градът е разположен е в Западните Родопи на височина 750 м, в живописната долина на р. Чепинска и отстои на 81 км от Пловдив и на 196 км от Смолян. Температурата на минералните извори е между 28–86° С. Известни са шест термоминерални находища – Чепино, Лъджене 1, Лъджене 2, Каменица, Драгиново и Варварски бани. Бликат около 80 извора, с общ дебит 170 л/сек, които по количество и състав съчетават едновременно лечебните възможности на водите в Хисаря, Баня и Наречен. Водите са с хидрокарбонатни и силициеви съставки, сяра и сероводород, а също и с благородния газ радон.
Какво лекува минералната вода във Велинград?
Курортът е профилиран за лечение на белодробни и ставни заболявания, на неврологични и гинекологични проблеми (в това число и стерилитет), на бъбречни, чернодробни, стомашно-чревни и много други заболявания.
Девин
В централната част на Родопите е разположен балнеолечебният курорт Девин. Минералните води са от няколко извора с голям дебит, разкрити чрез дълбоки сондажи. Температурата им е от 16° С до 72° С. Курортът се препоръчва за лечение на заболявания на опорно-двигателния апарат и на нервната система.
Какво лекува минералната вода в Девин?
Курортът се препоръчва за лечение на заболявания на опорно-двигателния апарат и на нервната система.
Момин проход
Климатичен и балнеологичен курорт, разположен в югозападните разклонения на Средна гора. Намира се на 73 км от София и на 83 км от Пловдив. От незапомнени времена градът се слави с минералните си извори, познати още по времето на Римската империя. Сега минералната вода от 9 извора, с температура 56° С, е събрана в един водосборен басейн. Водата на Момин проход е втора по радиоактивност след тази на лечебния курорт Нареченски бани, трета в Европа и двадесет и пета в света.
Какво лекува минералната вода в Момин проход?
Курортът е специализиран за лечение на хронични неспецифични заболявания на дихателната система, заболявания на централната и периферната нервна система, дегенеративни ставни, кожни и чревни заболявания. Добри резултати дава и лечението на постполиомелитни състояния при децата.
Павел баня
Курортът е разположен сред живописната Розова долина, на 18 км западно от Казанлък. Павел баня дължи своята известност най-вече на термоминералните си води, които са били използвани за лечение още в древността. От седем естествени и сондажни хидротермални източника бликат минерални води, с аналогична физико-химична характеристика – температура от 50° С до 61° С и с общ дебит 16 л/сек, или 1 400 000 л в денонощие. Всички води са с ниска минерализация (0.650–0.671 г/л), хидрокарбонатно-натриеви, с лека алкална реакция (рН 7.6), с ниска водна твърдост (1.7 немски градуса, т.е меки води}. Същевременно те са леко радонови, силициеви и умерено до силно флуорни. Има два хидротермални източника с нерадонова минерална вода и един с по-ниска температура на водата – 31° С. Всички води са бистри, безцветни, с приятни питейно-вкусови качества, макар и с лек мирис на сероводород, поради наличието на сулфиди (3 г/л).
Какво лекува минералната вода в Павел баня?
Заболявания на периферната нервна система – вертеброгенни заболявания (дискови хернии, стеснения на гръбначно-мозъчния канал, радикулити, сколиози, спондилолистези, спондилоатроза, травматични увреждания на периферната нервна система); травматични увреждания на централната нервна система, предимно на гръбначния мозък; дегенеративни неврологични заболявания; ортопедични заболявания – посттравматични и дегенеративни ставни и периставни заболявания; други заболявания – кариеси, гингивити и прочие.
Сандански
Международно известен климатичен и балнеолечебен курорт, разположен в долината на р. Санданска Бистрица, в подножието на югозападните склонове на Пир. На територията на Община Сандански има 6 минерални извора. Минералните води са хидрокарбонатно-силициева, сулфатно-натриева и флуорна. Курортът е специализиран за лечение на заболявания на горните дихателни пътища и белите дробове от нетуберкулозно естество и за възпалителни дегенеративни ставни заболявания.
Какво лекува минералната вода в Сандански?
Курортът е специализиран за лечение на заболявания на горните дихателни пътища и белите дробове от нетуберкулозно естество и за възпалителни дегенеративни ставни заболявания.
Сапарева баня
Балнеолечебен курорт, разположен в живописна котловина между планините Рила и Верила, по левия бряг на р. Джерман. Сапарева баня се гордее както със своята много студена и чиста планинска вода за пиене, така и с уникалната си минерална вода, която е една от най-горещите в Европа – с температура от 103° С. В центъра на Сапарева баня блика единственият гейзер на Балканите.
Какво лекува минералната вода в Сапарева баня?
Лекуват се заболявания на опорно-двигателния апарат, на периферната нервна система и гръбначния стълб, посттравматични състояния, ортопедични, дегенеративно-ставни, кожни и гинекологични заболявания.
Хисаря
Международно известен балнеолечебен курорт, разположен в южните склонове на Същинска Средна гора. Намира се на 42 км от Пловдив. В Хисар е поставено началото на организираното балнеолечение в страната. Има 22 минерални извора – 16 естествени и 6 чрез дълбоко сондиране, с температура от 37° С до 51° С и общ дебит 4000 л/сек. Водата е слабоминерализирана – 0,257 г/л, хидрокарбонатно-сулфатна, хлорна и натриева, флуорно-силициева, алкална. С висока стойност на рН – 9, без цвят и мирис, с приятен вкус.
Какво лекува минералната вода в Хисаря?
Минералната вода на Хисар може да се ползва като трапезна и за профилактика на: стомашно-чревни заболявания; бъбречно-каменна болест и бъбречно-урологични заболявания; жлъчно-каменна болест; заболявания на опорно-двигателния апарат; гинекологични заболявания; стоматологични заболявания и профилактика на зъбния кариес, хронична интоксикация с тежки метали и фармацевтични препарати.
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Тема
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Да предотвратим рака на простатата със зелен чай
[re: Mod vege]
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| Автор |
Mod vege (старо куче) |
| Публикувано | 11.02.17 23:32 |
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„Ракът на простатата е водеща причина за болест и смърт сред мъжете в Западния свят, но процентът на заболявания от рак на простатата в Азия се оказва десет пъти по-нисък. Може би генетично просто е по-малка вероятността те да се разболеят? Не, японците и китайците, които живеят в Америка, имат също висок процент на заболеваемост от рак на простатата.
В Съединените щати един на всеки трима мъже на около 30-годишна възраст вече има малки образувания на растящи ракови клетки на простатата си и те всъщност се превръщат в рак при почти две трети от американците до 60-годишна възраст. Чрез аутопсия се открива, че повечето възрастни мъже са имали неизвестни ракови тумори в простатата. Забележително е, че азиатците също имали преобладаващи от тези скрити латентни ракови образувания на простатата при аутопсия, но туморите не изглежда да са склонни да се развиват толкова, че да причиняват проблеми. В Япония хората по-скоро умират заедно с туморите си отколкото заради тях. Разбира се това се променя, тъй като азиатското население продължава да подражава на начина на хранене на Запад.“
Вижте цялата информация във видеото по-горе…
Източник:
Превод, корекция и обработка: Цветомира Енчева и Петър Енчев
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