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This will probably sound lame, but one of the most interesting history books I read was "Russia and the Golden Horde"

It gives a comprehensive breakdown on the impact of mongolian leadership on the development of the early russian state and also serves as a great introduction to the long history of medieval peasant revolts which are a constant in Imperial Russian history.

I had an awesome professor that let me do a custom course on the history of uprisings and revolts in Russia and it was some of the most fascinating things I've ever read, there's so many amazing stories from pugachev up to the bolsheviks. Personal favorite book is about the Anarchist Women that help assassinate Tsar Alexander II 5 Sisters: Women against the Tsar

You're welcome! I love helping people and want to teach in the future, so "thanks!" is probably my #1 favorite thing!

One thing I didn't mention in the above post that I'm starting to realize as I go through more higher level Math classes (Linear Algebra this semester) -- find MULTIPLE explanations for a concept and find MANY worked out, annotated problems.

This is coming up because I'm having a lot of difficulty with Linear Algebra. The calculations are simple (it's basically just solving systems of equations from pre-Calc), but understanding what everything means is a whole different story.

I spoke with some of the instructors in my colleges math department this semester and they all agreed on those two points. My Linear Instructor isn't bad, he just doesn't teach in a style I learn well in. Our textbook is alright, but doesn't have many examples worked out (maybe 3-5 per section, but each one is so fundamentally different nothing it's hard to understand what's being illustrated and why).

The Shaum's Outline series came highly recommended. The head of the department specifically cited Shaum's Linear Algebra for the reason she passed linear (she could never attend class and was teaching herself out of the textbook at the time, so the more help the better). While I can't comment on the Calculus version, I'm loving what I've seen so far in the Linear version. So if you ever need to see more problems worked out and Paul's math notes isn't doing it for you, try getting a Shaum's book. They're pretty inexpensive at around $10-20 on Amazon -- I picked up a used copy for $8.

I also picked up the No Bullshit Guide to Linear Algebra after a tutor friend recommended it. The author has a Calculus/Physics integrated version. It's pricy, but if you're having a difficult time understanding your Calculus book or just need a legitimately no-bullshit explanation of a concept, it's a great option. Again, I haven't seen the Math/Physics version, but if it's anything like the Linear one it'd be mad helpful.

Lastly, if you still need more examples or explanations, the book my college is using for Calculus is available here on reddit.

Not a problem. Ok, so if it's 14K can I assume you're based in the USA? I'm in the UK so I can only speak of my personal experience here.

Photographing jewellery is really hard, don't sweat it.

Firstly, a rhodium plate does go over the whole ring but it is only a micron layer and it does wear off. It wears off with abrasion, and the bottom of a ring will wear far more quickly than any other part of the ring. You definitely do not get a uniform change in colour as the rhodium wears. If you have worn rings either side of it, that too will wear the rhodium off of the edges of the ring, revealing the base metal alloy.

As I mentioned before, if the underlying alloy is very white or grey, then as the rhodium wears off the colour change is very minor and hard to notice. This is why we use high palladium alloys for white gold: they are grey-white and technically don't need rhodium, though we still add it.

Many of your pictures are casting colours from the surroundings so it's really hard to see, but I think that your entire ring has been made from an alloy of gold that is off-white. As your ring was sized down and no metal was added (except the sizing balls), it's almost certain that if you took some abrasive to the more-white looking top half of your ring, it too would show as yellow-ish.

There is no solution to this issue short of making a whole new ring. You can do a band-aid fix, and ask a jeweller for a heavy palnick plate (palladium-nickel), but that won't last that much longer than just rhodium.

There's no guarantee that I am right here, but if I had the ring in front of me i would be able to tell you in seconds. Any independent, well reviewed jeweller can tell you what you're dealing with. Just don't go to chain shops. Ideally, you want to speak to an actual jeweller who repairs/makes things, not a sales assistant.

This is probably not what you want to hear, but understand when you by 14K gold, you are paying for an alloy that contains 58.5% gold. There is no mention of any of the remaining alloy that can have an strong effect on diluting the yellow colour. Remember, gold is yellow. White gold is just an alloy trying to mask it.

Good luck with it, and remember, this is most defintiely a first world problem!!!

edit

One idea, if you have a Dremel or a rotary tool, you can get cheap polishing attachments for metal. Using a very soft attachment and a little rouge you can polish the metal of your engagement ring. Yellow and white gold is very hard to distinguish within the same ring when it is very shiny, regardless of rhodium.

Rouge example: https://www.amazon.co.uk/Bolpol-Jewellers-Jewellery-compound-Polishing/dp/B0134A2ZE6/ref=sr_1_5?crid=3U4169SJ5JLM&keywords=jewellers+rouge&qid=1564187160&s=diy&sprefix=jewellers+rou%2Cdiy%2C149&sr=1-5

Polishing attachments (soft cotton, nothing hard that can cause damage, these spherical ones are ideal): https://www.amazon.co.uk/NIUPIKA-Polishing-Buffing-Accessories-Mandrel/dp/B07H4D4K6T/ref=sr_1_5?keywords=dremel+polishing&qid=1564187139&s=diy&sr=1-5

This Dremel with the flexshaft is ideal for fine control polishing: https://www.amazon.co.uk/Dremel-4000-Attachment-45-Accessories/dp/B0033UWLXI/ref=sr_1_5?keywords=dremel&qid=1564187307&s=diy&sr=1-5

It's true. Only 60 million make it into the top 1%, with $34,000/year. Half of that 1% (29 million) live in the US. The number comes from Branko Milanovic's work, and his book The Haves and the Have-Nots.

Here are some articles on it from well respected organizations:

http://blogs.worldbank.org/publicsphere/inequality-and-rise-global-1-great-new-paper-branko-milanovic

http://foreignpolicy.com/2012/02/27/were-all-the-1-percent/

http://www.forbes.com/sites/garyshapiro/2012/05/30/we-are-the-worlds-one-percent/#7db36adf20f0

http://www.huffingtonpost.com/2012/01/04/americans-make-up-one-half-of-the-one-percent_n_1183713.html

However, keep in mind they all cite the same source, which is Milanovic and his book, and were all written at around the same time, so I assume it was Milanovic's publisher paying a PR firm to get these written. But that's pretty much how most media works now days. So if you are still skeptical of the number, I suggest reading the book, or finding some of Milanovic's published papers and reading through the methodology used to come up with his numbers.

Another fantastic book on the subject is Thomas Piketty's Capital in the Twenty-First Century. I highly recommend reading it. Picketty actually expected huge amounts of controversy when he released his book, and was surprised to find out that not many people disagreed with his methodologies and conclusions. Which is pretty scary in itself.

You can get a little cotton candy maker and several flavors of flossing sugar on Amazon for like 30 bucks. I recently bought one and it's awesome!




https://www.amazon.com/dp/B00EB8KRDM/ref=cm_sw_r_cp_apa_i_Kt2SDb0SNSVDY

Edit: oh and you can make any hard candy into cotton candy. Yes jolly rancher cotton candy is awesome.

Yes. Quite easily. The relationship is the following

If i have 1lb of force and want to lift something that weighs 4lbs i'll need two pistons right?

piston A with 1lb of force will have a surface area (pi*r^2) of idk, .5sqin.

piston B with 4lbs of load that you want to move will need a surface area 4x higher than piston A. so 2 sqin in this case.

The problem is when you move piston A 2 inches piston B (with the 4lb load) will only move .5 inches.

This scales linearly so if you want to lift a car with 1lb of force you can. but you better be able to move the piston a long long way to get the job done.

EDIT: a kit like this with some tubing will give you everything you need to demonstrate this at home. I don't know the tube diameters but you can measure them and figure out the ratio pretty easily. https://www.amazon.com/Pack-Refilling-Liquids-cigs-juice/dp/B01CFJ51X4/ref=sr_1_5?keywords=syringe&qid=1562950408&s=gateway&sr=8-5

Ours instructs to let it heat up for 10 minutes, which is just done by turning it on for 10 then off again. We don't wait the 5 mins between batches, we just refill the bowl with sugar when it's empty and keep going, with no issues yet!

It does get quite hot, I would recommend making sure your kid doesn't try to make any un-supervised if they're pretty young. Otherwise it's pretty easy, and the one we bought is extremely easy to clean as all the parts come off and can go into the dishwasher when we're done.

For reference, this is the maker we have.

James does some really great research and he's an incredibly good speaker if you ever get the chance to go see him. If you want to see something really disgusting try the model that Yulii Shikhmurzaev created, James did his phd thesis using it and I did my masters project (at a different time) on it, that shit is.... interesting. Its best described in the book but its described here and in several other papers.

Oh there was also a super interesting paper in JFM the other day here. ITs unfortunately almost entirely experimental, but some interesting stuff.

Looks like a clear version of these bead things for kids: https://smile.amazon.com/Rainbow-Growing-Tactile-Sensory-Decoration/dp/B071W18C3X?sa-no-redirect=1

These things are fucking fun btw, bought them for watering plants but they're great to play with too.

Have you tried a slow-feed bowl? I have two rescue dogs, littermates, abandoned at very young age and lucky to be alive. However when they were in the rescue centre they had to fight to eat and drink against other, bigger dogs so continued this behaviour after I took them in. Slow-feed bowls got them to slow down and eat/drink at a better pace and help reduce the amount of air the dog intakes when swallowing, meaning less burping. Something like this is what I mean: https://www.amazon.co.uk/JasGood-Eco-friendly-Durable-Non-Toxic-Preventing/dp/B01F8L63ZG/ref=pd_lpo_vtph_199_lp_t_2?_encoding=UTF8&psc=1&refRID=0A7T83D1NQB5VVKQS511

Yeah, I know what you mean. My guess is that their research involved "forcing thought changes" in people while they're under MRI, locating common patterns in this activity, and eventually arriving at their best current definition of a "thought."

(I'm recently interested in this subject after finishing reading "The Emotional Life of Your Brain", highly recommend it.)

Definitely. For further reading, I recommend Wiesel's Spaceflight Dynamics.

It is much easier for a satellite to maintain its orientation if it is spinning. Otherwise, it starts to drift and point in different directions. Satellites must then be designed to spin on one of the two stable axes, because if it ends up on the intermediate axis it will wobble (and you lose your TV, cell phone connection, etc.).

What this usually means is distributing the mass of the internal components a certain way, or even adding ballast weights to set the moments of inertia as desired.

A pack of playing cards may be a simple rectangular prism, but even a complicated object like a satellite exhibits the same dynamic properties... it's just a lot tougher to figure out what the axes are.

Beyond stabilizing satellites, any maneuvering in space needs to take these concepts into account. A maneuver on the intermediate axis will be unstable. Spacecraft need to either compensate, or perform maneuvers on stable axes as much as possible.

P.S. I think they have to be designed to spin on one axis actually, but I can't remember if it's the minor or major axis. As energy slowly decays, the spin will gradually transition to one of the axes... but college was a long time ago.

Just thinking about how to do it myself. I understand my method is most likely not how this was done but I can see it working still..

• Buy some of this stuff.
  
• Check the size of the image you would like to print.
  
• Buy some of these. in whatever size you'd like your image to be, maybe also grab an extra that is larger for a backplate.
  
• Buy a set of these to use as a stand for the printed plates.
  
• Grab something like this as a stand for the whole deal once done.
  
• Open up Photoshop and follow this guide on how to separate the colour channels into their own images.
  
• Print each channel to a separate piece of the Graphix film.
  
• Cut out your printed image and apply each to their own acrylic square.
  
• Take your larger square and drill two holes in it for the plate stands.
  
• Take two of the standoffs and put them in backwards. (these are designed to have the long metal tube behind the display, however we want it on the front.
  
• Remove two extra front covers (there are 20 standoffs and we only need 2) and then screw them onto the standoffs that we just put in backwards, essentially using the extra covers to dress up the front and cover the exposed bolt holes.
  
• Place your colored plates on the backing like in the photo and rest it on the stand purchased earlier
  
• In theory this should be complete now. I'm looking into buying the supplies and making one for a family member for christmas and if I do I'll post an update.

This is the best video on the subject I've ever seen. http://youtu.be/VBDoT8o4q00
Of you want to learn more I very very very strongly recommend this book. http://www.amazon.com/Code-Language-Computer-Hardware-Software/dp/0735611319

Code: The Hidden Language of Computer Hardware and Software is one of my favorite books and covers this topic. It's amazing.

This is a good book on the subject that I enjoyed.

Thermos Stainless Steel Beverage Can Insulator for 12 Ounce Can https://www.amazon.com/dp/B0000644AF/ref=cm_sw_r_cp_tai_OIFNzb1C5AA0D

This will keep a beer cold for 3 hours. It's glorious.