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Member (Idle past 1600 days) Posts: 20714 From: the other end of the sidewalk Joined: |
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Author | Topic: Are Uranium Halos the best evidence of (a) an old earth AND (b) constant physics? | |||||||||||||||||||||||||||
RAZD Member (Idle past 1600 days) Posts: 20714 From: the other end of the sidewalk Joined: |
What say peaceharris?
Are we in agreement that this is correct so far (Message 57):
quote: It doesn't really matter how many decay events are needed to cause a ring, we just use the observation that at time A we have a ring, and we use that to set the amount of decay needed for subsequent isotopes. Thus we need only concern ourselves with the blue diamond curve and how that decays. Because we don't know the actual time scale or the actual starting quantity we have to deal with decay of the daughter isotope in relation to the time scale of the parent decay. As noted in Message 53, this is done by the ratio of the half-lives H1 = half life of the parent isotopeH2 = half life of the daughter isotope The decay curve for the daughter isotope would be: And to convert this to measure t along the same parent time scale is a simple matter:or N/No = (1/2)^(t/H1)(H1/H2) with a^b•c == [a^b]^c (or [a^c]^b), then For the curves above and a hypothetical (H1/H2) = 5 we get the following: Where the brown square curve is the parent decay curve and the blue diamond curve is the ring production curve, as before, and the red triangle curve is the daughter decay curve on the parent decay curve time scale. The next step is to model how the blue diamond curve decays by the red triangle curve. Of course you can calculate it by your link site formula
where λ == ln(2)/H and e^-λt == (1/2)^t/H so we can write it as:and neglect the N2o (assume = 0) Multiplying the top and bottom of the first bracket fraction by H1•H2/ln(2), and dividing both sides by N1o we get: But we need to know how N2 (net remaining daughter at t=A) relates to NR (total daughter produced from t=0 to t=A to make the first ring) ...... where NR == (N1o - NA) = Nα238U (at 4.27 MeV) and NR - N2 = Nα234U (at 4.86 MeV). and NA = N1o•(1/2)^A/H1 so NR = N1o•(1-(1/2)^A/H1) or N1o = NR/(1-(1/2)^A/H1) and at t=A we would have: And with A = 490,000 years I get N2/NR = 54.16%, which means ~45.84% decayed into 230Th.
Message 49 ... at ~490,000 years I am getting ~45% of 10^9 230Th production from 234U decay, ... This is what the previous graph (see end of Message 53 note: edited to simplify) looks like with the values for 234U and A = 490,000 years: Where the red diamonds are the total daughter isotope (U234) production, the green squares are the net daughter isotope production at each time increment and the orange circles are the decay curve for the daughter isotope starting at 5%A, as before, and the blue circles are the remaining daughter isotope after decay, summed at each interval, and the grey diamonds are the total daughter isotope decay = total production of the next generation (230Th, the next bucket). In this (actual) instance the result is ~45.88% of the amount of decay needed to form a ring of the same density as the first ring ... except that this isn't the whole story: we still have the remaining isotopes to go, and the decay of 230Th and 226Ra have very similar decay energies and combine with the 234U decay to make the second ring. Cumbersome? Perhaps, but with the advantage of being able to use the same process for the next generation/s. Perhaps you'd like to check my numbers? Enjoy. Edited by RAZD, : == means defined as equal, added some for clarity Edited by RAZD, : added more Edited by RAZD, : added end Edited by RAZD, : clarity by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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RAZD Member (Idle past 1600 days) Posts: 20714 From: the other end of the sidewalk Joined: |
filling in the evidence
How do you know that the plane of the photo is not the fracture? By virtue that we are looking at a photo of a radiohalo, this suggests that the rock was fractured in this very plane. From Message 188 quote: Seems pretty clear to me. Enjoy. by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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RAZD Member (Idle past 1600 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Well, peaceharris,
Having validated my approach by getting virtually the same value for the decay of 234U to 230Th, we can now proceed to discuss the rest of the ring formation. Up to now we have discussed damage density as if it were constant for each ring, however in fact it should vary inversely with the radius of the ring. If we had single rings with the radii discussed previously (see polonium thread) with the same number of decay events, then (neglecting the duplications) we would expect to see: ring 1 = 238U decay = 4.27Mev = 14.1μm = 100.00%ring 2 = 234U decay = 4.86MeV = 17.0μm = 82.94% ring 3 = 222Rn decay = 5.59MeV = 20.4μm = 69.12% ring 4 = 218Po decay = 6.12MeV = 23.5μm = 60.00% ring 5 = 214Po decay = 7.88MeV = 34.6μm = 40.75% And to compensate for this decline with radius, to have the same density per unit area of ring we would need to see: ring 1 = 238U decay = 100.00%ring 2 = 234U decay = 120.57% ring 3 = 222Rn decay = 144.68% ring 4 = 218Po decay = 166.67% ring 5 = 214Po decay = 245.39% While there is no physical way to increase decay in daughter isotopes to more than the original parent decay (unless it is pre-existing), rings 2 and 3 are formed by multiple isotopes with similar decay energies. Ring 2 is formed from decay of 234U, 230Th and 226Ra, so if we set the time "A" such that these total 120% of 238U decay then we should have the same density ring visible. This occurs at ~550,000 years where I have: 234U ~50% 230Th ~35% 226Ra ~35% And because all remaining half-lives are less than 226Ra they will all be at ~35% Ring 3 is also composed of decay from multiple isotopes, 222Rn and 210Po, so the decay produced would be ~2x35% = 70% where we need 144.68% for a full density ring, so we should see 70/145 = ~48% of the density seen in the two inner rings. Ring 4 should be 35/166.67 = ~21% of the density of the two inner rings, and Ring 5 should be 35/245.39 = ~14% of the density seen in the inner two rings. This would give us an "embryonic" halo with ring density per unit ring area (compensated for radii) of: ring 1 = 238U decay = 100%ring 2 = 234U/230Th/226Ra decay = 100% ring 3 = 222Rn/210Po decay = 48% ring 4 = 218Po decay = 21% ring 5 = 214Po decay = 14% It seems to me that the amount of ring damage that we see in these outer areas is substantially, significantly, under the amount calculated based on the appearance of the two inner rings, and thus the only logical conclusion is that 222Rn, as a gas, left the sight of the inclusion in significant proportion and quantity. Lower density outer rings would have to show lower density for the second ring compared to the first for this to be an "embryonic" halo, and it seems to me that the second ring is slightly denser than the first. What we see is a partially formed halo due to 222Rn departure. Enjoy. Edited by RAZD, : added for clarity Edited by RAZD, : complete by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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cavediver Member (Idle past 3839 days) Posts: 4129 From: UK Joined: |
Seems pretty clear to me. Yep, I'm forced to agree
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peaceharris Member (Idle past 5792 days) Posts: 128 Joined: |
OK, I understand your method of explaining the embryonic halo and your math is correct.
The problem with your explanation is it doesn’t follow the principle of Uniformitarianism. You are assuming that the amount of U234 in the radiocenter was 0 initially and then showing that the embryonic halo is ~500000 years. If you start with the assumption that the initial activity of U234 was approximately the same as U238, (since this is what is observed in all natural waters and magmas today) you will be forced to reduce your estimate by a factor of ~10. If you want to insist that your assumption is reasonable, you should find a source where the amount of U234 is 0, then you can argue that possibly 500000 years ago we could find a similar source having no U234. The second problem with your method is it gives a lot of freedom to interpret data the way you believe it to be. While discussing Po-halos, you were arguing that the daughter products get accumulated in the radiocenter, and while discussing U-halos you argue that Uranium daughter products leave the radiocenter.
RAZD writes: Do you suppose they all formed along a single fissure plane in a easy to split crystal for some arcane purpose or because it was a fissure that allowed the radon gas to penetrate the crystal. Crystal rocks have cleavage planes that are weak so any crack would probably occur along the plane. Planes having more radiocenters will be weaker since radiation weakens bonding. Any radiometric method can be modified using your method to ”explain’ results different from the theory. You are basically doing what many geologists do to explain discordance of U-Pb dating of zircon. Whenever data plots below the Concordia curve, they say there has been Pb loss from the zircon. Whenever data plots above the Concordia curve, they say there has been Pb gain to the zircon. The difference between you and them is that you are claiming that there has been radon loss/gain to justify your theory, while they are claiming there has been Pb loss/gain to justify their theory.
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Coragyps Member (Idle past 930 days) Posts: 5553 From: Snyder, Texas, USA Joined: |
If you start with the assumption that the initial activity of U234 was approximately the same as U238, (since this is what is observed in all natural waters and magmas today)... Say what? U234 is a daughter of U238. What do you mean by "activity?"
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PaulK Member Posts: 17888 Joined: Member Rating: 8.3 |
What it means is that for every U238 decay there is a U234 decay i.e. the isotopes are in equilibrium.
Thus is seems that we have the following situation:
Message 46 states that RAZD made an error in assuming that U234 and U238 would be in equilibrium.
Message 65 states that the new calculation is not applicable because U234 and U238 WILL be in equilibrium. (The intermediate stages in the decay chain are so short that they won't have any significant effect).
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JonF Member (Idle past 363 days) Posts: 6174 Joined: |
Activity is the number of decays per second.
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Woodsy Member (Idle past 3569 days) Posts: 301 From: Burlington, Canada Joined: |
If you start with the assumption that the initial activity of U234 was approximately the same as U238, (since this is what is observed in all natural waters and magmas today) This is often not the case. Waters are known in which the U-234 is highly enriched. The decays leading to U-234 can leave it in a quite different chemical state from the parent U-238, through what are called hot-atom effects. Further, the intermediate nuclides have quite different chemistries. For example, thorium is often insoluble where uranium is soluble. If you are actually thinking of U-235, which is primordial, your comments are correct.
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peaceharris Member (Idle past 5792 days) Posts: 128 Joined: |
There are indeed many sources enriched in U234, but let’s be generous to RAZD. Even if he wanted to assume that the initial activity ratio of U234: U238 was as low as 0.8, we should allow him (see Florida Geological Survey | Florida Department of Environmental Protection )
The isotope percentage of U238 is 99.27%The isotope percentage of U235 is 0.72% Half life of U238=4.463e9 years Half life of U235=7.04e8 years So activity of U238 is 99.27*7.04e8 / 0.72/ 4.463e9 (=21.7) times greater than that of U235 This explains why people usually match only rings of daughter products of u238 while determining the origin of each halo.
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RAZD Member (Idle past 1600 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Thanks, peaceharris,
Message 62OK, I understand your method of explaining the embryonic halo and your math is correct. Good.
The problem with your explanation is it doesn’t follow the principle of Uniformitarianism. I don't like using that word because it is so misused that most people misunderstand what is being said. What I have done is assume that the basic physics that we know today were in operation during the formation of the rings, as (a) there is no evidence of any change in physics, and (b) the evidence of the rings says that the decay rates remained constant during the formation of the rings (decay rate being tied directly to alpha particle energy).
You are assuming that the amount of U234 in the radiocenter was 0 initially and then showing that the embryonic halo is ~500000 years. Correct. That is the starting point for this exercise. We already looked at what happens if we assume the inclusion to be in equilibrium at the time of the rock formation: in Message 46 your said:
quote: So now we look at the other extreme condition, with no daughter isotopes, to see what it would look like, and in this case we see that there should still be sufficient decay production of daughter isotopes to be visible once we have enough decay of 234U + 230Th + 226Ra to form a second ring at least as dense as the first ring (as shown in the picture).
There are indeed many sources enriched in U234, but let’s be generous to RAZD. Even if he wanted to assume that the initial activity ratio of U234: U238 was as low as 0.8, we should allow him (see Florida Geological Survey | Florida Department of Environmental Protection ) The problem is yours, for you are boxed in by both sides now. As PaulK noted, we started this with the assumption of equilibrium, and the equations showed that the rings would not be as seen in the picture. Then we went to the other extreme with no daughter isotopes, and again the equations showed that the rings would not be as seen in the picture, that we should see more ring formation in the third ring area that is seen. There is no intermediate stage that would result in removal of daughter isotope ring production, unless one of the isotopes is bodily removed from the vicinity, ergo the only logical assumption is that 222Rn (gas) has left the site of the inclusion in the picture.
So activity of U238 is 99.27*7.04e8 / 0.72/ 4.463e9 (=21.7) times greater than that of U235 And then the second ring would not be of the same visible density as the first ring, which is the condition of the halo in the picture. You need to explain the second ring to explain the picture. Enjoy. by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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RAZD Member (Idle past 1600 days) Posts: 20714 From: the other end of the sidewalk Joined: |
getting back to this comment, peaceharris,
Could you give us a photo of a fully developed Uranium halo. A halo where the 238U and the 214Po ring can be seen? These are provided by Gentry:
These are all well past the 500,000 year stage where the third ring would be visible
Anyway, if accelerated radioactive decay did not take place, how old are the Uranium halos in Gentry's paper? Pls tell me how you arrive at your answer. Old enough to form the rings, which can be a younger date than the rock, if the rock is fissured and allowed the entry of 238U particles into the structure after the rock was formed. Enjoy. by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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RAZD Member (Idle past 1600 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Thanks peaceharris,
The second problem with your method is it gives a lot of freedom to interpret data the way you believe it to be. Can you show how this affects the calculations? If there is "freedom to interpret data" then you should be able to show a different calculation with a different result.
While discussing Po-halos, you were arguing that the daughter products get accumulated in the radiocenter, and while discussing U-halos you argue that Uranium daughter products leave the radiocenter. The basic argument is that 222Rn is a gas, and as a gas it behaves like a gas: it leaves the original inclusion just as any gas would, and it behaves like a gas in attenuating to equalize partial pressures throughout it's available volume. This would mean over time that there would be a higher percentage of probability that the gas would decay at a location where there would be slightly more net molecules -- ie small voids that, while small, are many time larger than the fine fissures that permeate these kinds of crystals (those cleavage planes are there because there is not a perfect fit from one crystal layer to another).
Crystal rocks have cleavage planes that are weak so any crack would probably occur along the plane. Planes having more radiocenters will be weaker since radiation weakens bonding. Do you have any evidence of the radiation damage to chemical bonds? or is this just an ad hoc concept to ignore the fact that these fissures are characteristic of this kind of rock, and they were there before the halos?
Any radiometric method can be modified using your method to ”explain’ results different from the theory. You are basically doing what many geologists do to explain discordance of U-Pb dating of zircon. Whenever data plots below the Concordia curve, they say there has been Pb loss from the zircon. Whenever data plots above the Concordia curve, they say there has been Pb gain to the zircon. I know U/Pb calculations are a bete noir with you, however I don't think you can compare these. In this case we have:
And we are still stuck with a long time for the formation of uranium halos, especially the more complete ones that Gentry shows. There is no need to invoke special decay rates, no evidence for any change in the basic behavior of physics, and evidence in the rings of consistent decay energies for each of the alpha decay stages in the 238U decay chain. As such I think we are done with the 238U decay process, and any further discussion should be redirected back to the polonium thread at: Message 208 Enjoy. by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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peaceharris Member (Idle past 5792 days) Posts: 128 Joined: |
RAZD writes:
You first started assuming that all isotopes of the U238 decay chain were in equilibrium initially . If all isotopes of the U238 decay chain in the radiocenter start off being in equilibrium, then all rings would be visible. The very definition of ”embryonic Uranium halos’ is that the halos due to the decay of Uranium can be seen, but the halos due to the decay of other products of the U238 decay chain cannot be seen. The problem is yours, for you are boxed in by both sides now. Then you used the assumption that there is only U238 without U234, and explained that it could be 500000 years. No scientist would take your assumption seriously that 500000 years ago you could find a source with U238, but without U234.
RAZD writes: And then the second ring would not be of the same visible density as the first ring, which is the condition of the halo in the picture. Dude, you don’t understand anything!
RAZD writes: You need to explain the second ring to explain the picture. I don’t need to explain it, all I need to do is assume that others who read my posts understand that if U234 is in equilibrium with U238 when the rock is formed, the U234 ring will form simultaneously with the U238 ring. There are people who are able to understand this without me explaining it.
RAZD writes: The basic argument is that 222Rn is a gas, and as a gas it behaves like a gas: it leaves the original inclusion just as any gas would, and it behaves like a gas in attenuating to equalize partial pressures throughout it's available volume. No, Radon trapped in a solid doesn’t behave like a gas. It is known that helium and Argon stay inside the rock that has cooled down. People have experimented and found out that by heating a rock you can cause these inert gases to escape from the rock. The Radon atoms is bigger than both Helium and Argon, so it follows that it is easier for He and Argon to escape from a rock compared to Radon. Furthermore Radon -222, the inert gas being discussed has a half life of a few days compared to Argon and Helium that are stable. You are trying to convince people who know that Argon cannot inspite of being a stable atom that Radon-222 can escape within a few days! Good luck to you. Furthermore, even expert evolutionists have understood inert gases stay embedded in a rock that has cooled down. Joe Meert wrote, “The temperatures at which minerals close is easily verifiable through experimentation and this has been conducted numerous times including the famous experiments of Bowen” - One of the main objections to radiometric dating Creationists also have done experiments checking whether helium can escape from rocks and they also know that most helium is retained in the rock at low temperatures.
RAZD writes: Do you have any evidence of the radiation damage to chemical bonds? Try doing a google search on metamictization.
RAZD writes: or is this just an ad hoc concept to ignore the fact that these fissures are characteristic of this kind of rock, and they were there before the halos? There are scientists, (other than Gentry) who have concluded that Uranium radiocenters formed during crystallization. - refer Geochemical Journal Vol 10, pg 188. Are there scientists who share your view that fissures and Uranium radiocenters go together?
RAZD writes: I know U/Pb calculations are a bete noir with you, On the contrary U/Pb is one of my favorite radiometric methods. I have understood that U-Pb data can provide an upper bound for the age of the sample and I have used U/Pb data to show others that coal beds are few orders of magnitude younger than what evolutionists say. U/Pb calculations based on reasonable assumptions are a bete noir with you.
RAZD writes: And we are still stuck with a long time for the formation of uranium halos, especially the more complete ones that Gentry shows. Understanding embryonic U halos is a prerequisite to understand the more complete U halos, and I have no intentions to explain the more complete U- halos to someone who either doesn’t understand the embryonic ones or is in a state of denial.
RAZD writes: There is no need to invoke special decay rates, no evidence for any change in the basic behavior of physics, and evidence in the rings of consistent decay energies for each of the alpha decay stages in the 238U decay chain. We are in agreement here. But you need to invoke the unrealistic assumption that there was a source having U238, but without U234, 500000 years ago.
RAZD writes: As such I think we are done with the 238U decay process, I agree with you, there’s nothing I can do to convince you that embryonic Uranium halos are young. I am wasting my time reading your posts and replying to you.
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RAZD Member (Idle past 1600 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Thanks again peaceharris for your input.
You first started assuming that all isotopes of the U238 decay chain were in equilibrium initially . If all isotopes of the U238 decay chain in the radiocenter start off being in equilibrium, then all rings would be visible. The very definition of ”embryonic Uranium halos’ is that the halos due to the decay of Uranium can be seen, but the halos due to the decay of other products of the U238 decay chain cannot be seen. The problem is that this can also be due to the loss of 222Rn from the site of the inclusion, so the existence of two rings does not necessarily mean that the halo is embryonic.
Dude, you don’t understand anything! Given that you have check my math and my method and have not pointed out any errors in them, this seems to be more denial than anything else. Can you show how 234U can form the second ring without any decay of other daughter isotopes? Have you calculated what the resulting daughter decay would be?
I don’t need to explain it, all I need to do is assume that others who read my posts understand that if U234 is in equilibrium with U238 when the rock is formed, the U234 ring will form simultaneously with the U238 ring. There are people who are able to understand this without me explaining it. And yet you seem to be unable to explain it to me, and just repeat an assertion rather than offer any new evidence\argument. Would not starting with any initial 234U mean you are starting from a position between the two cases I have delineated? Both of these cases show that there should be more outer rings seen that in the picture.
No, Radon trapped in a solid doesn’t behave like a gas. It is known that helium and Argon stay inside the rock that has cooled down. People have experimented and found out that by heating a rock you can cause these inert gases to escape from the rock. The Radon atoms is bigger than both Helium and Argon, so it follows that it is easier for He and Argon to escape from a rock compared to Radon. Again the rocks in question have undergone secondary kinematic processes that have cracked the rocks. Comparing these to rocks that have not undergone the same process is faulty at best.
Try doing a google search on metamictization. Curiously I do not find where this process creates weak fracture planes rather than general and directionally nonspecific damage.
Are there scientists who share your view that fissures and Uranium radiocenters go together? This is where we started. There are scientists that have shown complete secondary replacement processes occurring in rocks like the ones with halos, resulting in less dense rock structure and plenty of opportunity for both the influx of the 238U inclusions and for the transport of the much smaller 222Rn atoms. See the Lithos (Collins et al) article on the polonium thread.
Understanding embryonic U halos is a prerequisite to understand the more complete U halos, and I have no intentions to explain the more complete U- halos to someone who either doesn’t understand the embryonic ones or is in a state of denial. Strangely this just seems to be another dodge rather than discussing the issue.
We are in agreement here. But you need to invoke the unrealistic assumption that there was a source having U238, but without U234, 500000 years ago. I think you are missing the point. The case of 238U without any other daughterr isotopes is taken as an extreme case to show the minimum case for developing subsequent rings. It just happens to work out to ~500,000 years as a minimum age. I'm perfectly happy to consider that the inclusions had several daughter isotopes when the inclusions were incorporated into the rock during the secondary (low temperature) reformation process.
I agree with you, there’s nothing I can do to convince you that embryonic Uranium halos are young. And yet, interestingly, all you have offered to date is repeated assertion of young age. You have not provided any kind of explanation at all, nor have you demonstrated that my math and method is erroneous. You are correct that just repeated assertion of a position without any substantiation will not convince me of it's validity. Enjoy. by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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