Wikipedia:Reference desk/Archives/Science/2016 December 18

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December 18[edit]

Asthma as a consequence of fighting off lung cancer?[edit]

It is well known that there is a link between lung cancer and asthma, typically attributed to tobacco smoking and confused diagnosis. [1] There is also some considerable overlap between autoantigens in people with asthma and those with non small cell lung cancer, though they can be told apart. [2] The responses have things like IL-9 in common. Question is: has anyone considered asthma as being, in some cases, the consequence of developing lung cancer and fighting it off?

For example, do some asthma patients have focal abnormalities in their lungs consistent with regressed tumors? Could locating and excising the remnants of a tumor cure a patient of asthma? Could transfusing whole blood from an asthma patient to a lung cancer patient be helpful? I'm wondering if anyone has been looking at the concept, or these sorts of ideas. Wnt (talk) 13:41, 18 December 2016 (UTC)[reply]

The asthma is too common to be a consequence of lung cancer. In addition the link that your provided above is concerned with the non-small cell lung cancer (not small cell lung cancer). Ruslik_Zero 19:25, 18 December 2016 (UTC)[reply]
D'oh, I should have watched what I was typing. Also, I didn't mean to suggest that all asthma arose this way - clearly there are model rat systems in which asthma is induced in healthy rats with antigens unrelated to cancer. That said, the increase in cancer in persons receiving lifelong immunosuppression gives the impression that the number of people who get cancer but recover naturally should be somewhere on the order of the number who are ultimately diagnosed, so to take a very crude guess I'm thinking there ought to be on the order of two million people yearly worldwide who have had lung cancer but will never know it. If they were likely to develop asthma symptoms, it would not be impossible to find them among the asthmatic population - though at 8.5% I think it was, it would definitely not be that easy. Wnt (talk) 00:12, 19 December 2016 (UTC)[reply]
I see there was a suggestion, lost to some pointless War on Banned Posters, that tuberculosis doesn't cause asthma. But I would not expect fighting tuberculosis to involve self-antigens as with cancer immunosurveillance (though immunology is rarely so simple as one hopes...). Wnt (talk) 16:54, 19 December 2016 (UTC)[reply]
The incidence of lung cancer is only modestly increased in persons receiving lifelong immunosuppression. So, the immunity is unlikely to play any significant role in the lung cancer development and the number of spontaneously resolved lung cancers is probably very small. Ruslik_Zero 20:25, 19 December 2016 (UTC)[reply]
@Ruslik0: From that publication: Lung cancer risk was most elevated in lung recipients (SIR 6.13, 95%CI 5.18–7.21) but also increased among other recipients (SIR 1.46, 95%CI 1.34–1.59 for kidney; 1.95, 1.74–2.19 for liver; 2.67, 2.40–2.95 for heart). SIR = specific incidence ratio, the number of actual cases / expected cases. So the immunosuppression ranges from adding (very roughly) 46% to 167% more cases than those normally observed. Now it is possible that these statistics aren't very specific and I should strike an average of about 100% extra incidents from immunosuppression, which is what I did; it's also possible though that heart transplant recipients actually have twice as many extra cases because they get more immunosuppression, which might mean that of every three actual cases of lung cancer two are stopped by the immune system before you know about them. (Of course, it is also possible that the drugs or foreign tissues themselves are carcinogenic, etc.; that's not a guarantee) All things considered, I don't think I was far wrong in the guesstimate I made above. Wnt (talk) 00:46, 20 December 2016 (UTC)[reply]
The modest increase of the incidence is most likely caused by the direct carcinogenic effect of immunosurpressive drugs or demographic differences or overdiagnosing. Ruslik_Zero 07:33, 20 December 2016 (UTC)[reply]
@Ruslik0: Apparently this is subject to ongoing research... looking up cancer rates in primary immunodeficiency it turns out that some cancers are much more common in those patients while others are not much altered: [3]; also [4]. This [5] cites hypotheses that lung cancer is a leading cause of death for AIDS patients due to reduction in adaptive immunity; one of its sources apparently said that a decline of CD4+ cells from >500 to 350-500 was associated with double the risk of lung cancer. True, what I have here is not an airtight case; there are alternate explanations for everything. But certainly it is enough suspicion that I think my original question is worth asking. Wnt (talk) 16:55, 20 December 2016 (UTC)[reply]

Tell me about ceramic non-stick coatings[edit]

Where did ceramic non-stick coatings come from? What are they made of? How are they made? I made the mistake of looking at some pots and pans on Amazon, and now all Google will give me is cooking pages. 50.43.36.155 (talk) 15:23, 18 December 2016 (UTC)[reply]

See Non-stick surface. Loraof (talk) 15:39, 18 December 2016 (UTC)[reply]
There's not much detail in that article, but the "See also" section may give you some good leads. StuRat (talk) 15:53, 18 December 2016 (UTC)[reply]
I'm trying a search on "ceramic non-stick coatings"... A colloidal silica manufacturer[6] says "While, when used to create ceramic non-stick coatings, colloidal silica acts as a co-binder. In both cases, colloidal silica helps increase surface temperature, hardness, and abrasion resistance properties of the resulting surface." A ceramic non-stick coating manufacturer (I think) says [7] CNSCs were "introduced in 2007 with the launch of GreenPan cookware in the U.S."; it claims advantages like harder, higher heat, no PFOA". Hmmm, no article for the product, pity (though a small one). Here's somebody else called Thermolon, and the term sol-gel technology comes up. [8] This group [9] which seems sympathetic to that company talks about generations of cookware with less and less chipping and heat intolerance and restrictions, and again, sol-gel technology - linking our article Sol-gel directly and linking this which is finally a bit more of what we're talkin' about: "Sol-gel technology is a hybrid of organic and inorganic chemistry. Coatings produced using sol-gel technology are more accurately described as ceramic-like; they feature many of the same characteristics as ceramic but to a lesser extent. Compared to PTFE, sol-gel coatings are harder (9H pencil hardness), and can function at higher temperatures (up to 450°C/840°F). " and
With sol-gel, the process is the opposite: the formulators start with the monomers and create the polymer on the pan’s surface once the coating is applied by means of a chemical reaction... there are five basic elements that make up a liquid coating before it is applied:
  • 1. The binder (or resin) adheres to the surface of the pan. It acts as the “glue”, providing adhesion and cohesion. It also determines the fundamental properties of the coating.
  • 2.The pigment provides the color.
  • 3.The “nonstick” component provides the release.
  • 4.The reinforcing agents add strength and wear resistance.
  • 5. The carrier (water or solvent), in which the other materials are suspended, which evaporates when the coating is cured. With sol-gel technology, the binder is synthesized during the curing stage. It provides a hard surface, similar to porcelain enamel, and is formulated in a way that allows good release without the use of fluoropolymers (e.g, PTFE).
At this point we're starting to get enough search terms to start looking this up on a more technical basis. Obviously every product is going to be different, and classifications can be drawn to put them together or apart, but these concepts ought to be useful. Wnt (talk) 16:11, 18 December 2016 (UTC)[reply]

What species of fungi is this?[edit]

What species of fungi is this? Found it on garden in Haifa, Israel.Uziel302 (talk) 20:00, 18 December 2016 (UTC)[reply]

To me it looks like it might be some sort of puffball. But I'm just going off superficial resemblance. Hopefully someone else can do better. If not you might try iNaturalist.
By the way, "fungi" is plural. It would be better grammar to ask "what species of fungus is this". --Trovatore (talk) 20:29, 18 December 2016 (UTC)[reply]
De fungibus non est disputandum. Not only are they much older, they are also in the majority and, most likely, will survive our species. Ex-Cookatoo, --194.118.189.163 (talk) 20:40, 18 December 2016 (UTC)[reply]
Or he could say, "What species of fungi are this?" It looks like it's wearing a skull cap. "Do all fungi wear those little hats?? "No, only the Orthodox." ←Baseball Bugs What's up, Doc? carrots→ 01:28, 19 December 2016 (UTC)[reply]
The ethnic jokes would be funnier if any of us had the slightest idea what this is. But identifying mushrooms isn't easy. It seems like there are people who can do it with amazing skill, and then there's the rest of us, and have you ever met anyone in between? Wnt (talk) 19:41, 20 December 2016 (UTC)[reply]

Tow hitch and rear end crash[edit]

How does a tow hitch affect the car's safety and material damage in a case of a read end collision? --Llaanngg (talk) 21:51, 18 December 2016 (UTC)[reply]

What kind of answer are you after? I'm not sure where the "mystery" is? Might be worth nothing that a tow hitch is NOT a bull bar. Its primary consideration is not absorbing impacts. In a low speed collision, the OTHER vehicle will oviously suffer more damage than if it hit a car without a tow hitch, HOWEVER on the car with the tow hitch, the force of the collision is transferred to the mount points of the tow hitch. While the mount points are strong, they are generally "rigid" so it does not take a big collision to damage the mount points enough to make repairs warranted, even if it doesn't really "look" like there's any damage. Vespine (talk) 22:18, 18 December 2016 (UTC)[reply]
A bit of googling comes up with some research that has been done which tells you it's a lot worse than the above answer would suggest. "If you look at the material properties of a tow-bar, it can be considered as a rigid element compared to the other components at the back of the car (e.g. plastic bumper). Therefore this change in rear-end structure can have influence on the crash pulse in a rear-end crash...The simulations of strategy 3 led to the conclusion that by adding a tow-bar there is probably a higher risk of getting neck injuries. [10] And from the US National Safety Commision website[11] "If you are involved in a rear end collision and you have a vehicle equipped with a receiver hitch chances are that the damage to your vehicle will be minimized. Although you may think this is a good thing, the biggest problem arises if you want to make an injury claim. Your insurance company will argue that since there is little damage to your vehicle, you could not have been injured – and that couldn't be further from the truth...but there are energy absorbing products on the market that you can install into your receiver hitch that will soften the crash pulse and make your receiver hitch safer. Do your homework because you really cannot afford to be without one." Richerman (talk) 12:56, 19 December 2016 (UTC)[reply]
One more... How crash severity in rear impacts influences short- and long-term consequences to the neck. Folksam Research, Stockholm, Sweden which says: "The crash tests showed that a tow-bar may significantly affect the acceleration of the car as well as that of the occupant [in a rear-end collision]. According to real-life crashes, a tow-bar on the struck car increased the risk of long-term consequences by 22% but did not affect the risk of short-term consequences". Alansplodge (talk) 17:44, 19 December 2016 (UTC)[reply]