Recent comments in /f/askscience

theluckyfrog t1_j9yes1a wrote

Reply to comment by 619364290163 in After a surgery, what happens to the air that was inside the incision? by cimmic

Well, in order I had a small bowel resection, a total colectomy w/ ostomy, and a relocation of said ostomy w/ a proctectomy and a separate small bowel resection. Thankfully, I did not need the big abdominal incision I was afraid of having for the procectomy--they did everything through the anal incision. I know they did some local anaesthesia to the abdomen with that last surgery but I was still shocked that neither it nor my previous ostomy hurt ANY. I assume all the credit goes to the continued advancement of surgery techniques--each of my surgeries was 8-10 years apart.

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SamQuan236 t1_j9ydlm5 wrote

Reply to Have there been any breakthroughs in Nanotechnology recently? How far away are we from seeing Nanomachines in an actual hospital? by by_comparison

You see nanomachines all the time. You just call them cpus, for example. Just because they arent flapping around doesn't mean they are not doing an important job. Health care (not my area) makes extensive use of computers.

Gate sizes are tiny - larger than advertised by cpu manufacturers, who like to redefine what their widths refer to but still incredibly dense. A finfet is about 20-30nm across the core, and is so small it is hard to get good imagery with common methods. This would not be possible without modern nanotechnology.

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CrustalTrudger t1_j9yaht5 wrote

Reply to comment by Bwyanfwanigan in How much do the different factors affect sea level rise? by Natural-Cap4008

Global networks of tide gauges for the "historical" sea level, which gets us back relatively accurately to at least the late 1800s. There are a variety of geologic records of sea level which we can use to build sea level curves going back well beyond historical periods.

> The same question has bothered me about climate measurements which in the past were not digital and inaccurate

If you want a deep dive on this, starting with something like the 'physical science basis' product of the latest IPCC report would be a good start. The short version is that we can place individual temperature records into context with a vast numbers of proxy data that allow us to reconstruct temperature (e.g., oxygen isotopes, clumped isotopes, compound specific isotopes, tree rings, etc.) and climate modeling that all tell us effectively the same thing.

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CrustalTrudger t1_j9y93si wrote

Reply to When a volcano erupts, does this affect the pressure building up in other volcanoes? by Rhamni

> When a volcano erupts, does this affect the pressure building up in other volcanoes?

Generally, no. At a simple level, any given volcano represents an isolated system, i.e., surface vents connected to a magma chamber within the crust, e.g., this diagram, while for a specific volcanic system is a decent generic representation to consider. If sufficient eruptable magma and conditions suitable for eruption exist (in terms of both volume of liquid, ratio of crystals to liquid, amount of dissolved gases, etc) within the magma chamber of a given system to cause an eruption, this will have no influence on other volcanoes because there is no connection between the systems.

The caveat would be if you're considering separate (but nearby) volcanoes that represent different vents or components of the same system. An example might be something like the big island of Hawaii where Mauno Loa and Kilauea effectively represent different vents of a related system (e.g., this super simplified diagram). Here we can see that while the two volcanoes have their own magma chambers in the shallow crust, they are "linked" by a single magma reservoir in the deeper crust. In detail, it's long been noted that eruptions at the two tend to be anti-correlated, i.e., one erupts which reduces activity at the other and then they switch, which many have assumed is related to competition for magma supply from the deeper reservoir (e.g., Klein, 1982). Further, there are suggestions that the eruptive process of one of these volcanoes might temporarily inhibit activity of the neighboring volcanoes through changes in the stress state induced by the eruption (e.g., Gonnermann et al., 2012).

In short, the eruption of one volcano has no bearing on distant volcanoes as there is no connection between their magma sources and the other changes that result from an eruption (e.g., changes in stress state) have a very limited spatial range. In the specific case of volcanoes very close to each other and that may share some portions of a magma plumbing system, eruption through one vent may influence (and specifically decrease) the activity of adjacent vents, but if there is a large pulse of magma that enters into all of the vents, then this "suppression" may not occur.

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sticklebat t1_j9y9092 wrote

Reply to comment by numatter in What does it mean for light to be an excitation in the electromagnetic field? by Ethan-Wakefield

> Given enough time, in theory, the entire mass of the magnet would eventually be irradiated outward as light energy.

I don’t think this would happen. I think the spinning magnet would preferentially emit light with polarizations that would slow down the magnet’s rotation over time, until it’s no longer spinning. I think hardly any of the magnet’s mass would be converted into light in this process.

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sticklebat t1_j9y8krp wrote

Reply to comment by Holgrin in What does it mean for light to be an excitation in the electromagnetic field? by Ethan-Wakefield

Rotating a magnetic does quite simply create EM waves, alongside other electromagnetic field changes. It just doesn’t only create EM waves. There is certainly nothing irresponsible or even really incorrect about their explanation. It’s a bit of a simplification, sure, but that’s appropriate in this context.

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