Wikipedia:Reference desk/Archives/Science/2019 November 8

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November 8

Looking for source on origin of "box" sequence nomenclature

This is a rare question on the ref desk that is explicitly asking for a reference. It is obvious to me from following citations that (at least in terms of literature - I have no idea if this phrase was used prior at a conference or something), the style of naming certain genetic sequences as "____ box" began when Walter Gilbert coined the term Pribnow box in Starting and Stopping Sequences for the RNA Polymerase. Cold Spring Harbor Monograph Archive, North America, 06 Jan. 1976. Available at: http://cshmonographs.org/index.php/monographs/article/view/3898/3115. He presented a number of recently published promoter sequences and discusses specific span of nucleotides that had been called out in earlier work by Pribnow. He draws a literal box around this span of DNA, and thereafter refers to it thereafter as the Pribnow box (first time in quotes as if defining it). The next couple publications to discuss the sequence cite Gilbert and use the name, but never say why it's called a box.

So to the request, as comfortable as I am saying that Gilbert coined the term, and this is why, and the rest are simply following a trend, it feels too close to WP:OR to use Gilbert's paper as the source for that. I'm wondering if anyone is aware of, or can find, a reliable source that explicitly describes the origin of this style of naming things. Thanks. Someguy1221 (talk) 04:17, 8 November 2019 (UTC)

There is some commentary in the lede of TATA box, but it doesn't have a definitive answer for the origin. DMacks (talk) 06:57, 8 November 2019 (UTC)

Yes, I had noticed that, and it seems problematic to me. It refers to the origin being unknown, but this seems to be unknown to the author of the Wikipedia article, as any mystery behind the origin is not mentioned in the cited sources. Actually nothing regarding the source of the name is mentioned in the cited sources. Someguy1221 (talk) 13:57, 8 November 2019 (UTC)

Are all electric blankets lumpy ?

The one I have has these cylinders between the layers, embedded in plates about 1 inch wide and 2.5 inches long. I take it these are thermostats which enable the electric blanket's wattage to be locally controlled, based on the temperature in that zone. That's fine, but when I roll over onto one of those it's as uncomfortable as it sounds. The actual heating wires, on the other hand, don't seem bad at all. So, is the design for mine universal, or are there less obtrusive versions ? SinisterLefty (talk) 05:41, 8 November 2019 (UTC)

Yes, there are many designs without the in-series thermostats. I used to have one like yours, and it was longer-lasting than the modern designs where all the monitoring is in the control box. I wish I could find one like yours, but they don't seem to be avaiable in the UK for safety reasons. Dbfirs 08:30, 8 November 2019 (UTC)

Is mine less safe ? I would think more thermostats, closer to the heat source, would better prevent overheating. SinisterLefty (talk) 15:57, 8 November 2019 (UTC)

Probably. But not as uncomfortable as those very un-ergonomic chairs. Martinevans123 (talk) 17:43, 8 November 2019 (UTC)

In a few minutes, you'd stop complaining, but this chair would give you quite the stiff neck. SinisterLefty (talk) 20:15, 8 November 2019 (UTC)

Oooohh! .... Forget IKEA!! Positively a chair to die for!! Wayne County 123 (talk) 20:30, 8 November 2019 (UTC)

Safety constraints are less demanding for an overblanket than for an underblanket that must remain safe while subjected to varying body weight and possible moisture. The OP's blanket may not meet the highest standards for an underblanket and, by intention or serendipity, be uncomfortable to lie on. DroneB (talk) 23:43, 8 November 2019 (UTC)

Do the lumps get warm? I wonder if they are resistors which have to run at fairly high current because of the low voltage electric blankets now use. In the old days the heating elements were driven directly by wall current through a thyristor dimmer. Talk about a hair-raising experience ;-). There is a trendy gizmo now called a bed jet (bedjet.com) that blows heated air under your regular blanket. The site is heavily sales-y and triggers my skepticism, but my mom has been interested in it and there is a long trial period, so she might give it a try. I've been quite happy with synthetic comforters and don't feel the need for heated blankets, at least here in California. 67.164.113.165 (talk) 07:20, 12 November 2019 (UTC)

No, the lumps don't get hot. That's interesting about the device that blows heated air, but I would also add moisture to it so it can be more humid there than in the rest of the house. (Too much humidity in the house in winter just condenses on the windows and causes mold.) And wow, that company wants $239 for a refurbished, non-returnable basic unit, and $900 for the full system. This is basically a hairdryer with a hose, right ? I would think you could do that for under $50. SinisterLefty (talk) 07:38, 12 November 2019 (UTC)

The $900 bedjet system must include two of the units and their weird blanket. The one my mom wants is about $400 and we are waiting to see if they do a black friday promo. They did another promo earlier in the year where you got about $100 off. I hadn't thought about making one using a hair dryer, but thanks for the idea, I might look into it. And because you reminded me of it, here is an amazing 43 minute video review of a $500 hairdryer: [1] (warning, NSFW language). 67.164.113.165 (talk) 20:46, 12 November 2019 (UTC)

For the hairdryer version you would want a powerful hairdryer, but set on low heat, and high fan, so it won't overheat from the increased resistance caused by the tube. You might also put some holes in the hose right by the hairdryer, so the air has a way out if the hose gets kinked. I'd test it thoroughly somewhere a fire won't spread, like outside, after rain ends. It probably would never be considered safe inside, without all sorts of safety testing, but you could at least see if there's any potential there with the outdoor test. SinisterLefty (talk) 21:54, 12 November 2019 (UTC)

Is there a difference between general electricity to the electricity of the heart?

Is there a difference between general electricity to the electricity of the heart? I'm trying to understand how to defined the similarity and difference between them. It's difficult for me to explain that human body has the electricity in his body. Initially It doesn't make sense to ordinary people who don't have knowledge in biology / physiology. What a short definition should include about it? ThePupil (talk) 21:44, 8 November 2019 (UTC)

Outside the body, electricity has 2 uses:

• Sending power (A/C or D/C).

• Sending information/signals (typically D/C, either analog or digital).

Sometimes it does both, as flipping a light switch on provides power to the bulb and also the signal that it's time to turn on. As for inside the body, electricity sends extremely low power D/C signals only. Most could be considered analog, like pain signals that have a variety of levels. But some could be considered digital, like a heartbeat timing signal, that just says "start beat now". Chemical energy is used by the heart and the rest of the body; electricity is not used for energy (other than the energy needed to send those signals, of course, but that ultimately comes from chemical energy, too). The nerve signals are also sent by a combo of electricity and chemical reactions. Chemicals are also used to send signals, as in hormones that tell an adolescent's body it is time to start puberty, for example. From an evolution POV, electrical signals have an advantage over chemical signals, because they are faster. If I got any of this wrong, somebody will be more than happy to correct me. :-) SinisterLefty (talk) 22:24, 8 November 2019 (UTC)

Could we not say that heart needs internal electrical power to contract repeatedly? ThePupil (talk) 22:35, 8 November 2019 (UTC)

I would change the word "power" to "signals", then it sounds good. SinisterLefty (talk) 22:37, 8 November 2019 (UTC)

Some confusion appeared because Luigi Galvani's experiments showed that the electricity we are now familiar with (he was not) promoted muscles mouvement in dead frog limbs. This would in turn prompt the Frankenstein style "let's use lightning as a power source to bring back life into a corpse", and the idea that muscles had "electricity". This is crude. The signals, for instance action potential, are not really electric, although it involves particles with an electric charge (just check the article);

I would use this analogy:

if the general electricity were a water flow in a canal, D/C would be water flowing in always the same direction, A/C would be water flowing back and forth, and body electricity would be the up and down waves without real flow

Gem fr (talk) 23:13, 8 November 2019 (UTC)

(ec)The first discovery that electricity has functions in the body was in the 18th century by Galvani who found that dead frogs' legs twitched when struck by an electrical spark, the beginning of the study of Bioelectricity. Today doctors use EEG to measure the tiny electrical signals that arise from brain activity to diagnose brain disorders. As SinisterLefty pointed out, the natural electric signals in the body have very low energy. The body will be damaged by Electrocution if accidently exposed to electric current levels that we use in Home appliances. Contact with as little as 20 mA (20 thousandths of an Amp) of current can be fatal, depending on whether the path of the current includes a vital organ such as the heart. Conversely, applying an electric pulse by a defibrillator can sometimes restore heart function. Execution by Electric chair was developed in USA and it applies some thousands of volts to the subject to ensure a fatal current flow. DroneB (talk) 23:31, 8 November 2019 (UTC)

• It's general knowledge that electricity has two forms: static electricity and electricity flowing in a circuit. Physiological electricity, such as in the heart, is neither.

Static electricity is a small amount of charge at a high potential. It's stored on insulators, or on conductors separated by insulators (i.e. capacitors). It's typically at a very high impedance, i.e. ratio of voltage to current. This doesn't flow, or (if it does) it's dissipates and isn't continuous.

Electricity in a circuit relies on conductors, i.e. typically metals, and has a relatively much lower impedance, i.e. greater current and lower voltage. There's a concept of current flow, in a loop.

Biology doesn't work in either of these ways. It's produced by the chemistry, not electrostatics. It's more like (dreadful anaology) being half a battery. A chemical potential at one end of a conductor (a "salty pipe") increases, relative to that at the far end. So there's a flow of electricity, but this is only measurable (in engineering terms) as a flow of charge, rather than a continuous and ongoing flow of current.

So, yes, it's electricity. But it's transient flows, not continuous. It's also very weak. This makes it hard to measure (look at the string electrocardiogram for one of the first diagnostic tools) and it's also quite easily overwhelmed by the application of an external current flow, such as from a defibrilator – which again is usually measured (in this context) in terms of energy (as Joules), rather than a continuous power rating. Andy Dingley (talk) 23:35, 8 November 2019 (UTC)

beware, static electric fields are huge in a cell. The voltage may be low (-0.1 V to +0.04 V), but the distance is so small (cell membrane is just ~10 nm thick), the electric field range in millions of V/m. A cell IS a capacitor, and quantitative models of the action potential looks like regular electric models.

Also, the main difference is that ions, not electrons, are the charge bearers for the (tiny) electric flows

Also, did we mentioned bioelectricity? Gem fr (talk) 08:44, 9 November 2019 (UTC)