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code_diego_code

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One day he'll see the light. My coworkers are still saying the same about me when it comes to monads and functional programming.

If nothing else, you can have your son write up a few one-function JS librarie, put them up on NPM, and hopefully collect some of Drew DeVault's money in time for Christmas.

Six year-old girl.

No time limit other than it needs to go away at bedtime.

She has her own kid's account on our streaming services on her tablet and some learning apps (ABCMouse, Khan Academy Kids, some Blockly-based beginner programming tools) and we gladly let her switch over to mom or dad's account if she's wanting to a kids' show that for whatever reason isn't on or got removed from the kids' side (e.g. Moana or Nat Geo's Weird But True). Our daughter is also welcome to watch recorded shows on the living room TV from our family's DVR.

She's also welcome to use phones and computers alongside mom or dad to call and video-chat with relatives or to look up information on the Internet.

We've taught our daughter that screens belong in the living room, to always ask permission if she wants to watch a "new-to-her" show on her device, which she's very good about doing. She also has our express permission to stop watching anything that she feels is too scary or otherwise makes her uncomfortable.

To combat the bad influences online, we have regular family discussions about the purpose of commercials and marketing, what's real and what's make-believe, that violence is rarely a good choice for any real-life situation despite TV, and that there are plenty of good people and content on the Internet but also some tricky ones that are out to hurt other people or steal their things: just like it is offline.

Having myself gotten onto the Internet in the early 1990s via "upcycled" computers and dial-up connections to local universities as a precocious tween with little parental help, I don't much faith in technological measures. As you might suspect, I was short on cash, rebellious, intelligent, and interested in all the wrong things online. Thankfully, those days were a lot more forgiving than our own time, and I ended up with a direct path to a career in software engineering rather untimely visits from law enforcement.

With that in mind, apples really don't fall far from trees. My daughter is already very interested in learning to type and wants to "write programs like dad," has her own ideas about how to efficiently guess mom and dad's passcodes, and is much more competent with social graces and persuasion that I ever was. I've no illusions about just how weak kids' accounts, Internet filters, passwords, or even netsec can be against a smart but bored kid with excess time on their hands.

For my wife and I, involved parenting, being truthful and upfront with our child, and modeling moral behavior has been our approach from day one. Besides, one day she'll leave home and will need to decide for herself.

I'm a former NMR spectroscopist (a chemist who works with the same technology as MRI devices--though at even higher magnetic field strengths to in order to study the shapes of various molecules). I've quite spent a lot of time working around high-field superconducting NMRs without incident.

To clarify the the "nuclear" part, magnetic resonance technology does not in any way involve nuclear reactions or the ensuing radiation from such, so you can rest easy on that one.

Additionally, MRI also doesn't utilize any ionizing radiation in the scanning process. This is one of the major advantages of imaging via MRI technology as opposed to using x-rays in traditional radiography or newer CT technologies.

What happens in NMR is that certain atomic nuclei like to align themselves with the magnetic field that they happen to find themselves in, much in the same way that you might see iron filings on a piece of paper aligning themselves with the magnetic field lines created by a toy magnet. This is where we get the M, or magnetic, part of MRI.

When these aligned nuclei are then exposed to radio waves, they will absorb and slightly later, re-emit the signal at specific resonance frequencies. This is where the R in MRI comes from. Now the trick is that the exact frequency where this happens depends on how the electrons surrounding that nucleus are arranged (which is mainly a function of what other atoms might be bonded to the one yu're looking at).

The timing and frequency at which this radio re-emission occurs allows chemists and radiologists to determine various bits of information about the different environments that these particular atoms have found themselves in, making it a very useful tool for determining chemical properties or non-invasively taking pictures of the interior of people's bodies.

Around very high-field magnets (particularly the superconducting types used in research NMR spectrometers and high-resolution closed tube MRI scanners), however, you do need to be careful about the magnets--and what ferromagnetic objects you may be bringing near or into them and how the field may affect them.

I trust most MRI techs and spectroscopists understand the proper safety procedures around their machines well enough to not allow themselves or their patients to create hazardous situations involving the magnets. These are some delicate and very expensive machines. That being said, failures can be quite spectacular--imagine Magneto and Iceman having a battle royale in your lab.

I think this is quite enough for one post, I'll leave the medical risks involving contrast dyes and incidentalomas to those more knowledgeable than myself.