Wikipedia:Reference desk/Archives/Science/2011 April 7

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April 7

Inspiration of Alain Carpentier

Can anyone please tell me what the inspiration of Alain Carpentier was to create his new artifical heart.

http://www.youtube.com/watch?v=7Rs1z9XigUA&feature=fvwrel

Please reply here or to (E-Mail address removed) — Preceding unsigned comment added by Sagar2727 (talk • contribs)

Better table salt (potassium, citrate, bicarbonate, magnesium, calcium, etc.)

Long ago I switched from using sodium salt at the table to using half sodium, half potassium; this was not because of health concern, but because to me NaCl has a perceptibly sour taste, and I had reached a point where I felt very hungry for salt, yet NaCl didn't seem satisfying but KCl was delightful. Now potassium chloride is a welcome addition to salt, but it's not truly enough: we know too well that the typical diet is deficient in calcium and magnesium. (Magnesium I especially value, as it seems to have an energizing effect on muscles throughout the body, including the heart) But that too isn't really sufficient: it turns out that the Western diet is apparently often deficient in alkali, resulting in acidic urine, kidney stones, and leaching of calcium from the bones. Now potassium bicarbonate supplementation appears to have a stronger effect on reducing blood pressure (and preventing the blood pressure increasing effect of NaCl) than the DASH diet. I should note that the NIH DASH diet dismisses supplementation without comment,[1] versus the Linus Pauling Institute's openness to the idea [2]; it makes me wonder which group really has the more scientific perspective.

Anyway, what I'd hope to hear about would be something better than Morton Salt Lite, something that has cations potassium (~50%), sodium (30% or so), magnesium (as much as can be added without bitterness), calcium (20% or more; as much as can be added without a hot taste), maybe a trace (not a clinical dose) of lithium in case it has some use; anions bicarbonate and/or citrate (apparently citrate is safer vs. kidney stones but somewhat harsh on the stomach), chloride as need be for flavor and to prevent excessive effects on stomach acidity, plus micro-nutrients like iodine, maybe a little fluoride, perhaps a non-toxic trace of bromine in case the gut bacteria find a use for it. Additional components from traditional African and Haitian salts from the land should also be considered, such as fine clay particles for absorbing toxins.

Has anyone sat down with all these compounds, worked out something that consistently tastes "salty" (I know for example that Epsom salt sometimes tastes very bitter, sometimes little taste, occasionally sweet as sugar - I have no idea what controls it)? Something that the manufacturer can roll together into consistent granules and used as table salt?

I have a feeling that I'd be lucky to find Sal aeratus (a mix of sodium and potassium bicarbonate for consumption favored in the 19th century), but I had to ask. Anyway, observations on the best salt supplement for all the myriad chronic conditions of life would be most welcome. Wnt (talk) 08:15, 7 April 2011 (UTC)

Salt substitute says it is pottasium chloride. Honestly I never managed to understand how NaCl is bitter, if you mean you eat it as it is, use smaller doses, also try salt with larger crystals and suck them one by one like candy ~~Xil (talk) 08:49, 7 April 2011 (UTC)

I hope I didn't give the impression NaCl seemed bitter - I just think that it has a slightly sour taste compared to the NaCl/KCl mixture, and I remember times when I was "hungry for salt" but NaCl didn't satisfy that. MgSO₄ seems quite bitter, sometimes but not other times, and anyone seeking to make a salt shaker that delivers the RDA of magnesium with normal daily use might have to figure out why. Wnt (talk) 19:46, 7 April 2011 (UTC)

I had heard that the pink stuff, which is sold as Himalayan salt granules, contains many more trace minerals than table salt. You may find this more to your palate. --TammyMoet (talk) 11:44, 7 April 2011 (UTC)

I can find that stuff online, but very little about its mineral composition. There are a huge variety of "sea salts" and evaporites available, but most of them are just NaCl with a little color. I didn't find an analysis of this one, but I suspect it has far more sodium than Salt Lite. (I assume the color is iron, said to be in the Himalayan salt, which might itself make a good addition to a salt supplement, but it would have to be only a fraction of the RDA in order to ensure against overdose). Wnt (talk) 19:46, 7 April 2011 (UTC)

Let me point out that sodium and potassium have totally different, and in some ways almost opposite, effects on the body. Potassium, once it is absorbed, is almost entirely intracellular; sodium is almost entirely extracellular. If the body is short on sodium, potassium won't work as a substitute, and can actually be harmful; the reverse is also true. Looie496 (talk) 22:29, 7 April 2011 (UTC)

Assuming that this carving is caused by defficiancy of something, wouldn't it be easier to find out what exactly the person is lacking (comparing nutrients in daily menu with recomended intake or doing a blood test or something similar) and then desining variety of salt most suitable? ~~Xil (talk) 02:14, 8 April 2011 (UTC)

Well, that should change over time, depending on nutrition. Generally the RDA system works fairly well - give the body a good dose of everything, and it can figure out how to spill the excesses. I assume that our ancestors would resort to salty deposits on land with a mix of minerals (for example in the Okavango Delta), and that sea salt was a rather recent and in some ways unfortunate innovation. Even so, admittedly, our ancestors likely received much more potassium and bicarbonate from fruits and vegetables, rather than by mineral supplementation. Wnt (talk) 04:29, 8 April 2011 (UTC)

Average weight of cattle

Hello. What is the average weight for male and female cattle if we take into account all breeds? I have been unable to find this information in the Cattle article. Thanks to anyone who can help. Leptictidium (mt) 09:51, 7 April 2011 (UTC)

Wow. That would be like asking for the average weight of a dog. The variation in different breeds of cattle is likely to introduce such a high standard deviation to the average as to make any such number meaningless. I've seen Hereford bulls, a beef cattle, which approach 3,000 pounds (1,400 kg), and Guernsey (dairy cattle) cows top out at around 1,000 pounds (450 kg). Finding an average between those extremes, averaged against all breeds of cattle in all parts of the world, might be technically possible, but the number doesn't tell you anything about an "average" cow anymore than the average weight between a chihuahua and a great dane tells you anything about an "average" dog. --Jayron32 14:42, 7 April 2011 (UTC)

As per Jayron32, are you perhaps seeking the range of weights for cattle? It might help to include the purpose of your question. 220.244.35.181 (talk) 14:46, 7 April 2011 (UTC)

This page has a table showing "Final Weight" for various beef breeds. This one has information on the weight of dairy breeds. Alansplodge (talk) 18:01, 7 April 2011 (UTC)

Estimating moisture content of meat by its weight loss

Assuming that raw meat has a moisture content of around 75%...
I want to estimate the moisture content of a piece of meat by its weight loss (through drying).
Example:
I take a 1000g piece of meat (with assumed moisture content of 75%) and hang it up to dry.
Three days later the meat weighs 500g. (This is 50% of its wet weight)
What is the moisture content of the meat?
Can I use this formula:

(Dried-sample-weight - (Original-sample-weight x 0.25)) / Dried-sample-weight x 100

thus:

 (500g - (1000g x 0.25)) / 500g x 100) 
=(500g - (    250g    )) / 500g x 100)  
=(       250g         )) / 500g x 100)
=50% moisture content  

?
220.244.35.181 (talk) 13:29, 7 April 2011 (UTC)
^{Note: The above has been edited after consideration of Lomn's contribution below}

No, that's not the method you want to pursue (what does that ratio actually represent?). Rather, I'd suggest determining identifiable physical aspects: (1) how much water is present originally? (2) how much mass is lost? (3) how much of that mass loss is water? — Lomn 13:52, 7 April 2011 (UTC)

I believe they came up with "75% moisture" through a scientific method (example) which involves taking a raw piece of meat, weighing it, then drying it until it stops losing weight, then re-weighing it. Because all the lost weight was water, you know the moisture content of the meat.

Thus:

"(1) how much water is present originally?"

In the example, 750g of water

"(2) how much mass is lost?"

In the example, 500g.'

"(3) how much of that mass loss is water?"

Presumably, all of it.

220.244.35.181 (talk) 14:15, 7 April 2011 (UTC)

Why petals of flowers dont have rectangular or square shape?

Hi Everyone! I am curious to know why petals of all flowers don't have rectangular or square shape (As far as I know, theres no any flower having square shaped or rectangular shape.)? Is there any advantage in having structure of petals that most of the plants have? — Preceding unsigned comment added by Ptamhane (talk • contribs) 13:38, 7 April 2011 (UTC)

Well here's another question, what else in nature is square? Practically nothing. Bee hives have a hexagonal lattice, but off-hand I can't think of anything in nature that's square, but there may well be. 220.244.35.181 (talk) 14:47, 7 April 2011 (UTC)

Answering my own (sub)-question: some googling reveals that lobster-eyes have allegedly square facets in them: according to this creationism site and "the cross section of the stem of any member of the mint family of plants is a square" and "When a lake or river bed dries up and the sediment is exposed and that too dries up mud cracks are formed which are sometimes perfect squares" 220.244.35.181 (talk) 14:55, 7 April 2011 (UTC)

There's "Walsby's square bacterium", which is terrific looking. There are cubic crystals, and a number of plant cells are roughly cuboid. I can't off-hand think of any macroscopic, squareish organism though. -- Consumed Crustacean (talk) 14:59, 7 April 2011 (UTC)

Yes, there are definite advantages to the shapes designs colours and odors of flowers. It's been shown that insects and other creatures are especially attracted to those particular attributes. Some types of flowers have markings that attract only one specific specie of insect which has specially adapted body parts to polinate only that specie of flower. It's a wonderous subject. Basically flower designs are whatever works best to attract the neccessary polination vectors.190.148.133.187 (talk) 15:27, 7 April 2011 (UTC)

I disagree. If flowers had square petals then bees would have evolved to be attracted to brightly colored squares. I propose that the issue is that petals are supported by the stem at one end. A square petal would not be well supported and would hang down. A cylinder is probably the ideal shape for a flower to be well supported, but would limit access and "visual advertising", so we end up with a compromise between the ideal shapes for support and for access. StuRat (talk) 16:11, 7 April 2011 (UTC)

Chemical series

Is polonium a post-transition metal or metalloid?? Is there even any reliable source saying that it is a metalloid?? Lanthanum-138 (talk) 14:17, 7 April 2011 (UTC)

Also, are there any reliable sources for colouring Mt, Ds, Rg transition metals; Uut, Uuq, Uup, Uuh post-transition metals; Uus halogen; Uuo noble gas (all not experimentally tested)? Lanthanum-138 (talk) 14:21, 7 April 2011 (UTC)

Position on the periodic table would indicate some hypothetical properties for these substances. Unfortunately, actual descriptions of their properties, which would allow us to classify them, would require us to actually have enough material to, you know, work with for a large amount of time. So some of the Uu? and beyond elements, which are attested to by a small number of atoms, which only existed for a few seconds, simply don't have enough material to classify. The deal with Polonium is that, while there's enough of the stuff around to work with, the properties do NOT neatly fit into one category or the other. Some people are passionately in support of Polonium being a metal, see [3], while others classify it clearly as a metalloid, see [4]. You'll note that both of these appear in highly respected journals published by the American Chemical Society, the first in J. Chem. Ed., and the second in JACS. What this tells me is that there's evidence that Polonium is probably not easily classifiable into the three boxes we, as humans, have artificially constructed to say "All things must be a metal, nonmetal, or metalloid". That simply doesn't work well for Polonium. In that way, it is somewhat akin to an element at the other end of the periodic table, Hydrogen, which also resists easy categorization into one of those three boxes; sensible chemists often consider Hydrogen to be in a class by itself and Polonium (and its neighbors Bismuth and Astatine) could likely also form some new "metalloidish" class... --Jayron32 14:35, 7 April 2011 (UTC)

What we've accepted now on WP is hydrogen - nonmetal (all right, it doesn't behave like a metal at STP), bismuth - metal (all right, it certainly behaves like one), polonium - metalloid (?); astatine - nonmetal (?). So I guess sources differ on Po (metal-metalloid) and At (metalloid-nonmetal). Lanthanum-138 (talk) 13:11, 8 April 2011 (UTC)

Hydrogen is a nonmetal based on purely physical properties alone. But its chemical properties; that is the sorts of chemical reactions it undergoes and the sort bonding it participates in and the sorts of compounds it forms, it actually doesn't fit well into either category in any meaningful sense. Sure, we can say gas at room temp = nonmetal, but the rest of it just doesn't work... For example, metal oxides are basic, nonmetal oxides are acid, hydrogen oxide is water; an amphoteric substance. Nonmetals tend to form more stable negative oxidation states than positive oxidation states; hydrogen most stable oxidation state is 1+. If you put a gun to my head and said that I had to classify hydrogen as one of the three groups, non-metal works best, but if you really want to understand the chemistry and properties of hydrogen, it doesn't really obey the "rules" we expect of nonmetals, which is why it isn't that helpful to classify it as a nonmetal. Real nonmetals like oxygen and nitrogen and sulfur and fluorine and chlorine have much more in common, chemically, as a class than hydrogen, which behaves chemically nothing like them. --Jayron32 15:44, 8 April 2011 (UTC)

You could make your own judgement about polonium based on the recently updated Metalloid article. I currently agree with Stephen Hawkes, author of the J. Chem. Ed. article,[5] and other related (earlier) articles, that polonium has too few ambiguous or non-metallic properties to warrant classifying it as a metalloid. It's more plausibly regarded as a post-transition metal.

The other interesting article, in the Journal of the American Chemical Society, discussed a new electronegativity scale.[6] The authors note that their electronegativity values for Bi and Po fall within the range of EN values (1.9–2.2) ascribed to metalloids. On this basis, together with some chemical arguments, they classify Po as a metalloid. Unfortunately, their chemical arguments appear to be at odds with the literature. They write that: 'What little is known about Po chemistry is consistent with non-metallic character: the oxides are acidic, and no cationic compounds have been observed' (p. 2783). However, the normal oxide PoO₂ is predominantly basic; polonium forms the rose-coloured Po²⁺ cation in aqueous solution; and many salts of polonium are known (see Metalloid for references). On the same page it looks like they undermine their own position by noting that 'numerous authors [such as e.g. Hawkes]…have classified…[Bi and Po] as metals, presumably because of their moderate conductivity and the (unique) primitive cubic structure of Po'. In this case 'numerous authors' look to be in a stronger position.

As I understand it, the contention about hydrogen is which group it should be assigned to. There are quite a few articles and references in the literature on this topic, arguing for its location in group 1, 14 or 17, or by itself in no group at all, or simultaneously in more than one group. As to whether hydrogen is better classified as a metal, metalloid or non-metal, I cannot recall seeing any appreciable uncertainty in the literature about this. The great bulk of opinion is that hydrogen is better classified as a nonmetal, regardless of its group assignment status. It has an ionization energy higher than that of bromine, xenon and chlorine. Most of its chemistry can be explained in terms of its tendency to acquire the electron configuration of the next highest noble gas, helium (Liptrot 1984, p. 161). Most of its compounds are covalent. Given these properties, it is reasonable to classify hydrogen as a nonmetal, on a first order sort basis. It then becomes useful to consider the reasons for the atypical nature of some of hydrogen's other properties—some of which were noted above—compared to those of other nonmetals. The same approach works on the other side of the fence, with respect to the unusual properties of e.g. Ga, Mn, Au (especially), Hg and Pu, compared to those of other more 'well-behaved' metals. Sandbh (talk) 03:42, 25 March 2012 (UTC)

Reference: Liptrot GF 1984, Modern inorganic chemistry, Bell & Hyman, London, ISBN 0713513578

Blood-brain Barrier

I understand that cocaine when snorted is one of the quicker ways to get the drug dorectly to the brain. But, what about other drugs or even gene therapy can it get to the brain through the nose or even ears or are they prohibited from the blood brain barrier? I thought that the nose was a direct pathway to the brain, but is the blood brain barrier still in place from the nose as well? —Preceding unsigned comment added by 71.137.246.99 (talk) 15:19, 7 April 2011 (UTC)

Yes, it's still in place. It obviously doesn't keep everything out, though. Also note that snorting cocaine destroys the cartilage in the nose over time, and you might have similar problems when snorting some meds. StuRat (talk) 16:02, 7 April 2011 (UTC)

I was going to dismiss the idea of blood getting from the nose directly to the brain, but as always with biology it's best to check the facts. Upon reading, "The anterior and posterior ethmoidal arteries originate from the ophthalmic artery and send numerous small branches through the cribriform plate to anastomose with nasal branches of the sphenopalatine artery (fig. 2B). This rich anastomotic network provides an important potential collateral pathway between the internal and external carotid circulations."^[7] (However, this doesn't say explicitly which way the blood usually tends to flow, and I haven't looked that up.)

That said, the blood-brain barrier is a much finer filter, separating the brain from the blood vessels much more closely. There's no way to put a magic filter in the carotid and stop up all the drugs as they go through the artery; it can only be done once you get to the point where blood cells no longer pass - i.e. the walls of the capillaries and beyond. This means that there is no way that the nasal arteries give special access through the blood-brain barrier, except in the sense that a drug might reach some parts of the brain faster by the connection described above, though I'm not sure. Wnt (talk) 20:07, 7 April 2011 (UTC)

It is possible for some substances to bypass the blood-brain barrier by being absorbed directly into the olfactory epithelium, inside the nasal cavity. There have been numerous experimental studies in which oxytocin was delivered to human subjects using a nasal spray, for example. See PMID 19747930 or, for a "sexier" article, PMID 18086171. Looie496 (talk) 22:19, 7 April 2011 (UTC)

I'm surprised to read this, but biology does have this way of defying all prediction. According to [8] "intranasal administration of the hormone presumably permits better brain access." I'm not sure why. PMID 10976589 says that intravenous oxytocin had "poor BBB permeability" and showed dose-dependent effects. It looks like this is on a borderline; maybe there are concentration-dependent phenomena involved. Wnt (talk) 00:12, 8 April 2011 (UTC)

Marketing prescription-only meds to the consumer

How do pharmaceutical corporations profit from their DTC marketing efforts of prescription-only meds? Do US-patients indeed suggest to their doctors to get a prescript of this or a little bit of that? Or, does it just work the other way round: US-doctors can prescribe it, since patients already know the meds? Quest09 (talk) 15:22, 7 April 2011 (UTC)

Short answer to your questions is "exactly that." The basic theory is that: 1. Consumer sees advertisement on TV. 2. Consumer says "I want that product." 3. Consumer goes to their doctor and demands product. 4. Doctor explains that there are alternatives, patient insists on the advertised product. 5. Advertised product gets sales. It's like any other advertisement: you convince people to buy your product and not the competitor's. In some cases, there is no competitor and all you have to do is convince the consumer that they need your product. Most people don't have a problem with 1-3 or 5, it's step 4 where people ignore alternatives because they've been brainwashed by the ad that makes DTC advertising unpalatable. Alternatives might be safer or more effective, but many advertised medications have cheaper alternatives that are as good or better and it's all about cost. SDY (talk) 17:38, 7 April 2011 (UTC)

But no serious doctor will take the word of his patient on this, I guess. You just cannot walk into his praxis and ask for Prozac to be happy or for Viagra to be happier in a more physical sense, can you? That would be using drugs for recreational purposes...Quest09 (talk) 17:55, 7 April 2011 (UTC)

Prescription drug ads are highly regulated in the United States and they can only claim to provide medical benefit in situations where such claims are very well supported FDA-regulated clinical trials. Basically the advertisements educate patients about which effective medications are available for various medical conditions. If patients are more aware of what medications may help them, they are more likely to see their doctor about treatment. So even when doctors won't prescribe medication unnecessarily, prescription drug sales are strongly affected by direct-to-consumer advertising. -- Ed (Edgar181) 19:00, 7 April 2011 (UTC)

To get a good understanding of this, consider restless leg syndrome. This syndrome was largely unknown to both patients and providers. Then, Requip commercials hit the air. Patients learned about this syndrome with very vague symptoms: Do you have trouble sleeping at night? Do you ever feel tingling in your legs? Do you wake up in the middle of the night? So, patients began asking the doctors about RLS and, basically, asking if they could try Requip. Sales of Requip soared with the introduction of the commercials. So, commercial-drug commercials can help sales of specific drugs. Also, there is a side-benefit. If the commercials make the company look good, the company's stock value will likely go up. -- kainaw™ 18:08, 7 April 2011 (UTC)

I think the strategy is more sophisticated than this. Suppose a company comes up with a new drug for a migraine headache. The drug is exactly the same as the existing generic drugs in every regard. So the company runs a study in which a fairly small group of people take either drug and write down a whole long list of migraine symptoms and whether they persisted despite taking the drug. Five people taking the old drug say that the light bothers them during a headache, and one taking the new drug says so. Summary: "the drug may be preferable in cases where light sensitivity is a problem". Company carpet-bombs the television with ads listing the terrible symptoms of a migraine, including "ooooh, that terrible sensitivity to light". Patients are thus coached to repeat back that symptom in the doctor's office. The physician, getting a sizeable kickback for prescribing the name-brand drug, says, "hey, I've got just the thing for you!" Wnt (talk) 20:13, 7 April 2011 (UTC)

And the result: The US spends ridiculously more per capita on healthcare than other developed nations with no measureably better standard of care. (The administrative costs of your insurance system are a factor too, of course.) --Tango (talk) 20:23, 7 April 2011 (UTC)

I wonder if another important factor in this is that if Doctor A won't prescribe a drug, the patient can go to Doctors B, C,... till they find one who will. The key step seems to be to get the drug name planted in the mind of the patient. Wanderer57 (talk) 20:32, 7 April 2011 (UTC)

There is a completely unfounded belief that generic medications are identical to brandname medications. I used to think the same way, but now I manage medical data for millions of patients and I can easily see that many generic medications are not equal to brandname medications. It could be that patients who are prescribed generic medications don't actually get the prescription filled, or don't take them properly, or don't take them at all. Regardless of the exact reason for the difference, there is a clear difference between the overall effectiveness of generic medications and brandname medications for many drugs (not all of them). Primarily, this difference is in the extended release forms of medications. So, whenever I supply data for a study on medications that are in extended release form, I know that I have to separate brandname and generic prescriptions. Then, to keep them on par with one another, I have to make a conversion factor such as "1 mg of brandname is equal to 1.3 mg of generic". This doesn't mean that everything the drug companies do is honest. I am only pointing out that the claim that every generic is perfectly equal to brandname medications is not valid. -- kainaw™ 12:22, 8 April 2011 (UTC)

This is one of their most dishonest tactics. If you're manipulating data based on this lie, you have no business doing medicine or science.

At least in the US, there's a small difference between generics and innovator products that's tolerated on a variety of factors in pharmacokinetics such as peak concentration, plasma half-life, and such, but there's batch to batch variability in the innovator drug that also creates "non-identical" drugs. The "generics are worse than innovators" argument has no basis in chemistry or biochemistry, it's just an oft-repeated old wives' tale by pharma to ensure sales of the more profitable innovator products. SDY (talk) 15:28, 8 April 2011 (UTC)

I am looking at actual patient data to form my opinion of generics vs. brandname. You claim it is a lie without any evidence and tell me that I have to quit my job. Why should I believe you? Can you provide anything to convince me that the data I see is completely wrong? Here's an example: I am looking at over 1,000 patients who had prescriptions for Tegretol and then switched to Carbamazepine. Now, I count up ICD9's of 780.3 that should be minimized with this treatment. I get an average of 0.7/month before the switch and an average of 1.1 after the switch. As I stated before, this is a controlled-release medication. So, I am not surprised there is a difference. Is it a difference in EVERYONE? No. Are there some who do better after the switch? Yes. But, overall, I see that the generic controls convulsions worse than the brandname. -- kainaw™ 18:28, 8 April 2011 (UTC)

I am looking at legal requirements and carefully constructed double-blind, sometimes placebo-controlled, sometimes crossover, clinical trials that prove the generic drugs are bioequivalent either through pharmacokinetics or through what are more or less repeats of the original phase III trials used to approve the drugs in the first place (aka an Abbreviated New Drug Application, probably #078115 for the case you're talking about). Assuming people aren't buying their generics from fly-by-night internet pharmacies, there should be no clinical difference between the two - they should have similar bioavailability, half-lives, etc... I'm claiming it is a lie because the equivalence of generics is a legal requirement: if they actually were not as good, they would be illegal in the US. Could there be a problem with that particular drug or formulation? I can't rule it out without looking at the data, but it seems highly unlikely and there's a huge financial incentive for Novartis to claim that the namebrand is more effective since the extended release carbamezapine just went off patent protection (Feb 11 according to the approval letter on that ANDA). What is the source of the data you're looking at? Is this blinded trial data, anecdotal reports, HMO data? If it's data produced by Novartis, I'd treat it with extreme caution. SDY (talk) 19:00, 8 April 2011 (UTC)

I am looking at data directly from outpatient clinics (the primary care provider's data) merged with hospital data - which is my job, to merge outpatient and inpatient data for analysis of real-world data. I do not argue that the actual ingredient is inferior. I only argue that the end result - for whatever the reason may be - is that in the extended release medications there is a trend in which the brandnames perform better at their function than the generics. Before this was my job, my opinion was that generic medication was equivalent to brandname medication. Now, I do not accept that as a simple fact. -- kainaw™ 19:15, 8 April 2011 (UTC)

The actual ingredient is the same, and the way it interacts with the body is the same (plus or minus some small tolerances, plus or minus lot to lot variability), so that it behaves differently seems more than a little unlikely.

Are there any other trends in the data that might be confounding the results? Possible confounders include severity of disease or comorbidities, the way the drug was stored, etc... Non-trial data is complicated, often too complicated to be useful because the confounding factors are sometimes surprising.

It's theoretically possible that one of the excipients in either drug has some clinical effect independent of the active ingredient and that would produce a difference, and it's theoretically possible that some trace contamination has a clinical effect independent of the active ingredient, but these are highly unlikely. Simply put, that a brand name drug would be consistently better than a bioequivalent generic is a bit more probable than water memory: not impossible, but if it were proven true a lot of intelligent people have been very wrong. SDY (talk) 20:56, 8 April 2011 (UTC)

Let's be clear: are you comparing apples to apples here with the generics? I understand perfectly well that not just the dosage but also the formulation of a drug matters for its effectiveness. (we just had a tedious argument about that with the pill splitting...) Are you comparing a generic drug to one with a patented time-release formula that the generic is not permitted to use? Or are you saying that the generic manufacturer tried to make the exact same pill but nonetheless did a shoddy job of it? Wnt (talk) 21:02, 8 April 2011 (UTC)

I'm talking about comparing Granny Smiths to Granny Smiths: the ANDA linked above is a specific drug (apple) made by a specific company (tree) that should be clinicially the same as the original drug (apple) made by a different company (tree). The formulation might not be exactly identical because of the excipients, things like coatings and fillers. These matter a lot for an extended release formulation, but the expectation (which is tested in human trials) is that critical parameters like release rates are the same. The active ingredients are the same and in the same dose. SDY (talk) 21:27, 8 April 2011 (UTC)

Yes, but (a) your link takes me to a general search menu, and (b) your position is that they're the same, and I'm not sure that's what kainaw is comparing to claim a difference. Wnt (talk) 23:44, 8 April 2011 (UTC)

It must cache something. Just type the number there as the search term and it comes right up. I can only assume that Kainaw is talking about the same thing: "generic" is a term of art when it comes to drugs. SDY (talk) 00:08, 9 April 2011 (UTC)

Not to intrude, but isn't the placebo effect commonly cited as the reason why brandnames outperform generics, since repackaging the same medication in a shinier box often makes it more effective on patient populations? To be clear, I am not saying this isn't a real effect, I am saying that it can be a real effect without any actual difference in the actual pills. The placebo effect seems to interact with less disconcerting, biochemical effects of medicine in strange and poorly-understood ways. 86.162.71.235 (talk) 23:13, 8 April 2011 (UTC)

In this case it may be a Nocebo effect if patients are told they're getting the cheap stuff instead of the "real thing." That's likely part of the reason why Kainaw's data does not agree with well designed double-blind studies. Gossip propagates the myth that the generics are somehow inferior and it ends up being a very expensive self-fulfilling prophecy. SDY (talk) 00:01, 9 April 2011 (UTC)

Which of course means that, in the real world, brandname pharmaceuticals are more effective, unless you invest in educating/reassuring your patients effectively. Maybe generics should be sold in shiny red boxes with sparkly-sounding names? 86.162.71.235 (talk) 00:06, 9 April 2011 (UTC)

The treatment might be more effective, the drug is the same. A hair-splitting distinction, to be sure, but a distinction nonetheless. There are cheaper ways to use psychology to help patients than spending ten times more on a medication. SDY (talk) 00:22, 9 April 2011 (UTC)

Well, certainly, but which do patients care about? The drug, or the effectiveness of their treatment? Anyway, the result is that Kainaw is right to observe and measure a difference that really exists, although you can pull your hair out at the circumstances that allow the distinction to exist. Perhaps some of this energy should be spent on finding way to make genetics more psychologically effective? I've always been quite fond of a muted version of homeopathy being available through doctor referral, so that the patient is also receiving any chemical treatment necessary and having the condition monitored by an actual doctor, while receiving effective placebo treatment. I'm aware, however, that others disagree. 86.162.71.235 (talk) 10:17, 9 April 2011 (UTC)

As SDY notes, while I have no reason to doubt that Kainaw's data say what he says they do, without a lot more information I'm not sure that I would draw the same conclusion from them. If patients are aware that they are changing (or have been changed) from a name-brand to a generic version, the effect Kainaw observes may be nothing more than nocebo. (We already know that expensive placebos are more effective than cheaper ones.) For that matter, is it known why the patients are changing from one drug to the other? Did the ones switching to the generic do so because their health insurance coverage lapsed or for other financial reasons; in other words, are the 'switching' patients unusually stressed or otherwise exposed to factors unrelated to their medication which might affect their risk of convulsions? TenOfAllTrades(talk) 19:20, 9 April 2011 (UTC)

I don't think we should entirely rule out the idea of variation in quality without thinking it through. As stated at generic drug, "The FDA requires the bioequivalence of the generic product to be between 80% and 125% of that of the innovator product." While one would like to see a system in which companies rewarded with market exclusivity for 20 years have to pay back a little by letting generic manufacturers tour their plant, read their memos, and get the exact specifications on every last detail, so far as I know that does not happen. When it comes to a choice between capitalist doctrine and patient health, doctrine will win most of the time. It is possible that the generic companies simply don't know every last trick involved in certain things like time release. Alternatively, the lower price of their product may give relatively less financial incentive to spend money on hair-splitting issues. Of course, given that so many dosing decisions are being made by doctors deciding whether to give 100% or 50% more, 25 milligrams or 50 or 75, the 20% variation in generic dose may not be all that significant. Wnt (talk) 16:12, 10 April 2011 (UTC)

While I've only "pseudo-scanned" through it ... nice discussion, folks. And I just have a second to give you an anecdote. I can say, from both personal experience from getting treatment for my own lumbar spine AND from talking to a TON of other folks licit and illicit, that there are VERY clear differences in effectiveness of preparations of hydrocodone/APAP 10 mg./325 mg. combination products. The white ones made by Mallinckrodt Pharmaceuticals are CLEARLY inferior to the yellow ones that "street" folks refer to as "bananas" (can't remember the imprint code on those, it's been a while). I would bet you my house I could distinguish between the two EVERY TIME under blinded conditions. While 2 "bananas" takes away my pain COMPLETELY, 2 of the white ones still leave me noticeably hurting (and wanting another one). The "effect size" is CONSIDERABLE, yes-sir-ee-Bob. Would LOVE to see some true double-blind comparison data on this ... but DON'T NEED TO. To me, its a "Sun rises in the East" situation.

P.S. To kainaw™ - like your thinking on your "conversion factor" convention-thingy (above), but BOY ... I'd be VERY careful :-)

Best regards:

Cliff L. Knickerbocker, MS (talk) 11:39, 12 April 2011 (UTC)

Cells

I had another question I wanted to ask seperately. I spoke with a man when I told him I have cancer and he told me about a center that saved his friend's life that they removed most of his blood and replaced it. Not sure the exact details of procedure but that made me think, my question is would or is it possible to remove just cells from the body or even the brain or other organs such as the liver, like cancer cells? —Preceding unsigned comment added by 71.137.246.99 (talk) 15:23, 7 April 2011 (UTC)

If you want advice on your own treatment, you need to speak to your doctor. The big problem in any cancer treatment is distinguishing the cancer cells from the rest of your cells. They are almost identical, but you have to kill or remove the cancer cells without harming too many of the rest of your cells. What you describe is basically what all cancer treatments try to do, with varying levels of success. --Tango (talk) 15:36, 7 April 2011 (UTC)

In some cases they try to remove the cancer cells, mainly by surgery, while in others they try to kill them, say by chemotherapy or radiation therapy, or by drugs which aid the body's own defense system in identifying and killing the cancer cells. StuRat (talk) 15:57, 7 April 2011 (UTC)

Wikipedia has an article titled Management of cancer which the OP may find informative and interesting. --Jayron32 16:11, 7 April 2011 (UTC)

The organs are made up from cells, the treatment for cancer is to hunt down an destroy cancer cells, but certainly organ cells can't be transfused like blood. Multiple blood transfusions is treatment for some types of cancer (I think leukemia was one of them), however it is not full blood exchange ~~Xil (talk) 16:22, 7 April 2011 (UTC)

We really need to know the type of cancer in as much detail as possible ("small cell", "stage IIb", etc.) to have any real shot at providing useful information. Wnt (talk) 20:15, 7 April 2011 (UTC)

No, I think we don't. Answering this question in general terms is OK, but if you start answering for his specific cancer it starts to border on the type of medical advice we can not give. Ariel. (talk) 00:07, 8 April 2011 (UTC)

What's the difference between talking about cancer or talking about a type of cancer? I wish that the so-called "ethical" people around here would at least bother to refer the victims of their attentions to someplace more specific than "bugger off". Wnt (talk) 00:17, 8 April 2011 (UTC)

He was talking about somebody's friends cancer, seems like he is asking about some fuzzy idea he has, because somebody told him blood transfusion cures cancer or something, rather than asking for a medical advice ~~Xil (talk) 02:05, 8 April 2011 (UTC)

To provide one general piece of information, I found a FAQ about clinical trials at [9] which gives basic background and refers to ClinicalTrials.gov and CenterWatch.com. A treatment past the clinical trial stage is probably more likely to be known to most physicians. I would also strongly urge the OP use the NCBI PubMed database at www.ncbi.nlm.nih.gov to look up papers about his specific cancer - both for information about known and experimental treatments, and because the e-mail addresses provided by the authors of those articles might be worth contacting for further information or to find out about relevant studies. Wnt (talk) 00:22, 8 April 2011 (UTC)

Super glue removal from skin

Resolved

 – Nail polish remover worked to remove almost all of what an Adhesive Tape Remover Pad failed to get. Ks0stm ^(T•C•G) 17:55, 8 April 2011 (UTC)

Having just built a bridge out of newspaper and glue, my fingers are covered in super glue (this particular kind appears made from ethyl cyanoacrylate and Polymethylmethacrylate). I have tried washing it off with soap and water, however this doesn't get it off. The best method I have found of getting it off is the rather dubious method of my putting more on so that it makes a thinker covering that's easier to peel off. I asked my physics teacher and he wasn't sure of the best way to get it off other than just picking at it. A classmate recommended hairspray. Before I get home and try getting it off with hairspray, what are some other good methods of removing super glue from skin in case the hairspray doesn't work? Ks0stm ^(T•C•G) 17:50, 7 April 2011 (UTC)

Look here. Alansplodge (talk) 17:54, 7 April 2011 (UTC)

(edit conflict)After setting up, acrylates are particularly resistant to just about any solvent, which is why they make a good glue. Anything that would dissolve them would likely give you a nasty chemical burn; unfortunately the only thing I have found to reliably get super glue off of skin is patience. If you pick at it slowly, after several days (yes, days) it will loosen enough to come off, probably due to the natural sloughing of the skin cells under the glue. (post EC comments). Or you could try acetone as the page Alansplodge provided; in my experience the dilute acetone found in household nail polish remover isn't all that effective, but I guess if you work at it you may find success. --Jayron32 18:00, 7 April 2011 (UTC)

One can often find stronger solutions of acetone in the paint section of hardware stores, where it is sold for surface preparation before painting. One should be a little careful, though, as, unlike nail polish remover, the paint aisle acetone isn't intended for use on human skin. (An additional caveat is that many nail polish removers sold these days are acetone-free. Though they may function identically to remove nail polish, they may not be equivalent in removing cyanoacrylates.) -- 140.142.20.229 (talk) 18:55, 7 April 2011 (UTC)

The only thing I found that removes superglue from skin was soaking in hot water. --TammyMoet (talk) 18:27, 7 April 2011 (UTC)

Acetone, commonly found in nail-polish remover, will soften cyanoacrylate. See this data-sheet for PermaBond brand 941-CYA superglue. Use caution with acetone - it's not good for your skin; in nail-polish remover, it's usually around 3% or 5%, but if you get 90% or other high-concentrations (suitable for immediately softening CYA) at a hardware store, it's pretty noxious and can cause rashes, dry-skin, and other problems. Then again, cyanoacrylate isn't exactly good for your skin either. If you have a serious amount of superglue, or if you're sensitive to acetone or other solvents, consider seeing a dermatologist. Nimur (talk) 19:07, 7 April 2011 (UTC)

Practically speaking acetone only harms skin with long term exposure, which is hard to do because it evaporates so fast. Acetone is my go to choice as household solvent for removing glue, etc, because its toxicity is very low, and it works so well. Ariel. (talk) 00:05, 8 April 2011 (UTC)

In my experience, acetone dries out your skin, because it strips the oils off, but your skin will just make more over then next few hours. My biggest concern with acetone is that it is extremely flammable, so don't take a smoke break directly after cleaning your hands. Googlemeister (talk) 13:18, 8 April 2011 (UTC)

I agree in general; acetone is pretty safe overall. But on the RefDesk, I try to be very safety-conscious and err on the side of caution. There are enough random people on the internet encouraging reckless behavior; it doesn't hurt to have one or two people encouraging caution. Nimur (talk) 16:26, 8 April 2011 (UTC)

Soap and hot water is usually recommended as the safe alternative, though I agree that it works mainly by softening the skin rather than by dissolving hardened superglue. Dbfirs 16:28, 8 April 2011 (UTC)

Strange lightning-like flashes inside a room every night

Hello. Every night for the last five nights I've seen a sudden, bright flash in my bedroom at 2 minutes past midnight. The flash is very rapid, lasting only a fraction of a second. At first I thought it was lightning, but I noticed the flash on the second night occured at exactly same as the one on the first, and the three since then have confirmed then.

At first I thought they were coming through the window, but they're not, they seem to be eminating from the ceiling itself. They're certainly not cars (I've listened to cars passing for the last 11 years). The night before last I managed to get quite a good glimpse and when the flash occurs, a small roughly circular section of the ceiling seems to light up, almost like the focus of light from a torch. Yet it isn't a torch, there's nothing outside and I have curtains that would scatter torchilight. Again, they happen at the exact same time every night.

What the heck could this be? I'm absolutely baffled here. I had a poke around in the attic and saw that a few wires crossed over my room, I spread them out a bit, but could it really be anything to do with those wires?--92.251.129.133 (talk) 20:10, 7 April 2011 (UTC)

I suspect that it's some electronic device in your house that has an LED status light that blinks for some reason at regular intervals. It could be a lot of things. The hard-drive light for your computer, for example. Or perhaps a light on a phone or answering machine?

Some LEDs can be surprisingly bright, and will seem even brighter if your eyes have had time to adapt to the dark. APL (talk) 20:18, 7 April 2011 (UTC)

The only electronic device in that room is a television, quite an old one, and I never put it on standby.--92.251.129.133 (talk) 20:20, 7 April 2011 (UTC)

This is the beginning of a great sci-fi story...

Seriously, I suspect the light would be coming from below an opaque ceiling, shining up on it, rather than above it. If you can put an X on the center of the spot that glows, you can tape a piece of paper two or three inches below it with an X directly below your first X. The image of the spot on the paper should be displaced in the direction of whichever piece of electronic apparatus in the room is projecting the spot of light. Or you can just look around them and find one, try unplugging half of them and half of those, etc. (edit conflict: I see you say you don't have them. Are you sure? Power strip, cable box, anything?) Wnt (talk) 20:20, 7 April 2011 (UTC)

Is there any sound at the same time? If so, I would guess you have some kind of electronic device on a timer that turns on (or possibly off) at that time (it's probably supposed to turn on at midnight and the clock is set wrong). Perhaps an electric boiler on an Economy 7 type deal. When the switch turns on, there is an arcing, which produces the light you see. This would tend to produce a blue-ish light. --Tango (talk) 20:38, 7 April 2011 (UTC)

A clock, a radio, cell phone, any plug-in or battery operated device? Is there anything new in the room that was not there before the flashing began? Is the room door kept closed? Wanderer57 (talk) 20:44, 7 April 2011 (UTC)

My smoke detector does this when the battery is going dead. There is also an audible "sqaulk" that accompanies it, but I have noticed that, a few days before the squalking starts, there indicator light flashes in the manner described by the OP. Since a smoke detector is the sort of thing that most people don't even notice (unless it is going off) perhaps it could be that. --Jayron32 20:50, 7 April 2011 (UTC)

If I had a question about something occurring over a long span of time, I would aim a video camera at the location and set it to record for 6 hours on the slowest VHS mode. With today's digital technology, perhaps a camera with a solid state memory card, or a camera connected to a PC could be used to record all night, yet with the temporal resolution to detect any brief transient flash such as you describe. You would want to make sure it provides an accurate time record. I sincerely doubt that something happening between wires in the attic could be visible through the ceiling, without burning the house down. Using a videocamera would divide the possibilities between it being a real illumination from whatever source, like an LED flashing from some smoke detector or cell phone with a dying battery, or some internal perception not originating in the outside world, like a dream, or a hypnopompic or hypnogogic image. The weirdest happenings can have the most mundane explanations. In college one morning, lying in bed, I heard a barely audible sequence of brief tones: 1 ding or tone, followed by 2, followed by 3, repeating for several minutes. It was at the absolute threshold of audibility, where it might have been real or imagined. If I moved a foot away, it was inaudible. Only in one spot could I hear it. I hypothesized that it was a hallucination, a message from extra-terrestrials, or whatever. Going out into the corridor and down the hall, I was able to hear it outside another dorm room. It turned out that one guy had an alarm clock which rang one ding, then 2 dings, then 3, repeating, and he was too lazy to get up and turn it off. Edison (talk) 04:28, 8 April 2011 (UTC)

The fact that the spot is circular, rather than elliptical, means that the LED must be just about straight under it, pointing up. I have an LED indicator on an air filter which is so oriented, and sure enough makes a blue circle on the ceiling. That device makes the circle whenever it's on. I also have walkie talkies which, when charging, seem to feel the need to make a little beep once a day. Combine those two things together, and you would have something that makes a blue, circular flash on the ceiling once a day. So, just look for anything electrical straight under where the spot occurs. (I sure hope you tell us what it is when you find it.) StuRat (talk) 05:12, 8 April 2011 (UTC)

I'm not telling you you're imagining it, but warning you that you might be: beware Hypnogogia#Sensory_phenomena. Bright flashes are experienced by a friend of mine: I myself get a sound from time to time, a kind of "wumph" as if I'd just jumped into water. I also get hypnic jerks, but I think everybody has those. If you're completely awake when the flash happens, disregard, but "two minutes past midnight" made me suspicious. 81.131.37.40 (talk) 08:03, 8 April 2011 (UTC)

In regards to the "wumph" sound, see exploding head syndrome, an awesomely named encyclopedia article if ever there was one. Matt Deres (talk) 13:10, 8 April 2011 (UTC)

I doubt if it's "all in his head", because it happens at the same time every day, and looks like it's something timed to occur around midnight. Those sound like characteristics of an electric device. StuRat (talk) 18:16, 8 April 2011 (UTC)

This is a bit of a farfetched suggestion I know. A small flashing light somewhere in a room could produce a circular area of light on the ceiling if the original light was reflected off a circular mirror. The difficulty with this theory (or at least one difficulty with it) is that the initial flash would have to be brighter and therefore more noticeable than the reflected light circle. Wanderer57 (talk) 19:40, 8 April 2011 (UTC)

That's not so far-fetched. If the light is in a tight beam and the air and mirror are clear, there may not be as much ambient light as you would expect. Also, the original light source might be in a place where it isn't visible directly. I've seen light spots in odd parts of the room before, only to trace them down to a reflective surface. StuRat (talk) 19:56, 8 April 2011 (UTC)

Poppy seeds

Do poppy seeds have morphine in them? --70.244.234.128 (talk) 20:51, 7 April 2011 (UTC)

Yes, see Poppy_seed#False_positive_drug_tests. But the amount of morphine in a poppyseed-seasoned bagel, for example, is likely to be somewhat close to the amount of cocaine in a can of coca-cola; i.e. not zero, but not enough to cause any affect on your body. --Jayron32 21:02, 7 April 2011 (UTC)

Not morpine, opium. Yes, but not very much at all. Eating a couple dozen poppy seed muffins might be enough to test positive for opiates in a urine test, but it won't get you high thx1138 (talk) 21:03, 7 April 2011 (UTC)

Actually, if you read the article, there have been positive confirmed tests after eating much less; you can show a false positive for opiates after eating only 3 or so pastries/bagels/muffins with poppyseeds in them. That doesn't necessarily mean that this is clinically enough opiates to "get you high" (it isn't), but the threshold level for the drug tests is necessarily much lower than the amounts needed for psychoactive effect; since the test is designed to catch you several days after taking opiates; i.e. when you are no longer feeling the effect, but trace amounts are still in your blood after using. If you have eaten a poppy seed item shortly (say a few hours to a day) before taking the test, it CAN lead to false positives. --Jayron32 21:06, 7 April 2011 (UTC)

It seems like that assumption, that "there's a little in them now, so there must have been a lot previously", is fundamentally flawed. Relying on this bad assumption is sure to provide many false positives. In another example, suppose you were testing alcoholics for tiny amounts of alcohol. Well, those tiny amounts naturally occur in foods, so yet again, a small amount of blood alcohol is no indication that the alcoholic is hitting the bottle again. StuRat (talk) 04:59, 8 April 2011 (UTC)

Unfortunately, employers are often willing to take that chance. Generally, there are MANY more qualified applicants for a job then there are positions availible, that means that employers are willing to not hire someone who has a "poppyseed false positive" because there's also a chance it's a "heroin junky who took a couple of days off so he could interview for a job". If they hired the second guy, the risk to the company is FAR greater than if they decline to hire the first guy, since there's probably someone whose just as qualified as the first guy who didn't eat a poppyseed bagel that morning, the company has no reason to differentiate between true positives and false positives. --Jayron32 15:29, 8 April 2011 (UTC)

That's where laws are needed, to prevent discrimination based on unreliable tests dependent on poor assumptions. StuRat (talk) 18:13, 8 April 2011 (UTC)

Why? So long as discrimination isn't based on race/gender/sexual orientation/national origin/age or other protected categorizations, employers are free to hire whom they think will do the job the best. --Jayron32 19:05, 8 April 2011 (UTC)

You seem to be using circular logic: "it shouldn't be illegal because it isn't currently illegal". I think that rather than having protected classes, it should be illegal to discriminate in hiring or promotion for anything not proven to affect job performance. StuRat (talk) 20:08, 8 April 2011 (UTC)

Of course it is an unjust invasion of personal privacy, and a demonstration of the need for positive economic, social, and cultural rights, in particular a right of access to gainful employment, but, though important, we're not going to settle the issue here. Wnt (talk) 20:57, 8 April 2011 (UTC)

@StuRat: I'm pretty sure people who are habitual heroin users have a lower job performance potential than people who are not. --Jayron32 06:06, 10 April 2011 (UTC)

Yes, but people who eat poppy seeds aren't. So then, why should it be legal to toss them all into the same category ? StuRat (talk) 06:22, 10 April 2011 (UTC)

Because the risk of hiring a heroin junky is worse than the risk in not hiring a poppyseed bagel eater. Positive tests for opiates are correlated with job performance, unlike numerous other ways in which an employer may discriminate against an applicant. That there are false positives does not mean that the real positives are a negligible risk to the employer. --Jayron32 06:31, 10 April 2011 (UTC)

You're assuming there is no way to distinguish between the two. If a drug test shows "opiates", they can send them to a doctor to check for needle tracks and other signs, can check with former employers, etc. Just refusing to hire anyone who eats poppy seeds isn't necessary. StuRat (talk) 17:27, 10 April 2011 (UTC)

Literally opium is poppy sap, so I'm not sure I'd say there is opium in the seeds. Both opium nd the seeds contain morphine - just in very different concentrations. Wnt (talk) 23:56, 7 April 2011 (UTC)

Turning Jupiter into a sun

Is it possible to turn Jupiter into a second sun? ScienceApe (talk) 22:20, 7 April 2011 (UTC)

This was discussed recently. Staecker (talk) 22:27, 7 April 2011 (UTC)

Short answer: "No".Zzubnik (talk) 08:12, 8 April 2011 (UTC)

... unless you have a monolith to hand. Gandalf61 (talk)

>akbarmohammadzade

I think human can do so... look that if we add one of jupiters moon mass to it it will be a star , we can send all earth nucleic bombs and explod IO or ganymide then bring it to roche limit and fall on jupiter .then the human will release of that bombs .(INSHALLAH) dont think about that our sun is here for several billion years dont worry 78.38.28.3 (talk) 15:59, 9 April 2011 (UTC)

Look at the mass figures for Jupiter's moons vs. Jupiter. Tiny. And Jupiter's moons are vastly larger than small asteroids like 99942 Apophis that we can barely nudge with all our efforts. Likely humans will have something vastly bigger than nukes someday, but for now there's not enough uranium in the solar system to do anything. Wnt (talk) 02:05, 11 April 2011 (UTC)

akbarmohammadzade

any interstellar object with mass Jupiter +moon will have especial condition and inner pressure and heat for beginning fusion and carbon cycle for nucleic reactivity , i did not say that our uranium can case Jupiter to be star , my plan is this (for Imagine only):this is my forecasting of such event

1)first we send nucleic bombs toward one of Jupiter moons (for example Métis or Io) 2)if we bombard it with bombs it will EXPLOD(If all nucleic bombs explode they can explode 5 times earth ) 3)METIS is closer moon to [[roche limit ]], and will fall on Jupiter 4)Jupiter mass will Increase (the IO and Ganymede have more mass)with adding it 5)fusion nucleic reaction will began and JUPITER will be a star 6)the magnitude of Jupiter will be first in sky after moon and sun 7) it can create a shadow of objects 8)some nights it will reduce the visibility of other stars 9)the radius angle of it remain stable 10 )it will send poor energy 11)we will see it at day 12)IT can case creating shadow of moon on earth 13)it will send light on invisible part of moon and we will see it wonderful 14 )it will has hot winds and storm 16)it will effect on our radio relations--~~~~ Iran university of science and technology (IUST) ......

I looked this up, mostly because I'd forgotten Metis existed. But to be specific: Metis (moon) has mass 3.6 ×10¹⁶ kg, volume ~42,700 km³. Io (moon) has mass 8.9319×10²² kg, volume 2.53×10¹⁰ km³. Europa (moon) has 4.80×10²² kg, volume 1.593×10¹⁰ km³. Ganymede (moon) has mass 1.4819 × 10²³ kg, volume 7.6 × 10¹⁰ km³. Add these all together (ignoring all compression) we have mass 18.53 x 10²² kg, volume 11.7 x 10¹⁰ km³.

Now the mass of Jupiter, no moons added, is 1.8986×10²⁷ kg. With the moons added, its mass is 1.8988×10²⁷ kg. See the difference? But you need 13 times the mass of Jupiter to fuse deuterium (not hydrogen) and cross the boundary between a giant planet and a brown dwarf. Which still isn't much of a star.

The volume of Jupiter is 1.43128×10¹⁵, but you won't get 1.43135×10¹⁵ by throwing in the moons, because everything from Jupiter to a brown dwarf has pretty much the same volume. Being rocky, they might even shrink it, slightly. But just for purpose of illustration, consider that Jupiter might have a rocky core very roughly 12 to 45 times the size of Earth, beneath a vast sea of metallic hydrogen. If the satellites sink down to that, well, the volume of the Earth is 1.08321×10¹² km³, so they would add about 1.4% volume to the rocky core, divided by however many Earth volumes it actually is - so about 0.1% for the 12 times Earth mass figure. Spread out over the surface of one Earth they would form a layer 1.5 km thick. Impressive... but no star.

Now dropping these stones into Jupiter may not make it a star, but it should release some energy. Europa has a velocity of 17 km/s, Metis more (but it's too small to matter), the others a bit less. To be very quick and dirty, let's take kinetic energy = 1/2 (18.53 x 10²² kg) (17 km/s) (17 km/s) = 2.7 x 10²⁵ kg km^2/s^2 = 2.7 x 10³¹ J. Double that to 5.4 x 10³¹ J assuming that they sink all the way to the center of the planet (for a circular orbit, kinetic and potential energy are each half of the total). That's 1.3 x 10²⁸ "Calories" (kcal), in case Jupiter has been dieting. Now each Calorie is enough to raise the temperature of a kilogram of water by 1 C. I don't know what the heat capacity of (mostly) metallic hydrogen is - no one has ever made any - but it's probably less. Jupiter has a mass of 1.8988×10²⁷ kg, so by my calculations (which may well have gone wrong by now) I think the planet would actually feel this collision, raising its overall temperature by a full seven degrees C! But no ... it's not a star. Even if you keep the heat in the upper 20% atmosphere layer, make it 35 C - no, less than that, because half was potential energy, it's not a star. You might, of course, manage to cut up and scatter the moons perfectly to make a lovely meteor shower all over the planet at once that would look like a star, but only for a short while; emitting its light so fiercely the upper atmosphere would just cool down again.

I know it's an appealing idea in a way, to give a failed star a second chance and so forth, but any real implementation of the scheme is basically just a giant fusion power plant, entirely artificial. Wnt (talk) 23:55, 13 April 2011 (UTC)