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Me to my sister: "You know it means he got arrested for prostitution sometime while in the Air Force, and we never knew about it, right?"
Not necessarily. My grandmother is pretty deep into Alzheimer's, and she invents stuff all the time. Your brain just finds ways to reinterpret and explain things around you when you don't remember stuff. To explain why my grandfather is never around, she says he's always gone somewhere, for some reason (war, cheating on her, vacation, he left her, ect.; usually bad stuff). He has been dead for 10 years, of course.
I bought my first flip phone after nearly everyone I knew had been using them for years. I replaced it when the battery died. I used that second one for 5 or 6 years until I decided to get a smartphone (iPhone SE, I like the small size) in order to have navigation to replace/supplement my very old Garmin Nuvi whose maps are way out of date. I really like the airline apps when I fly, Lyft when I need a ride, and of course Google Maps which not only is always up to date, but also knows traffic flow in real time. Having access to the cloud for those documents I want to be able to access from anywhere is also nice. And I can show people my pictures, or read whatever I happen to have on Kindle or Libby, without having to bring my tablet. It even has an app to keep the inside of the screen clean, called, simply enough, ScreenClean.

I expect to upgrade it when the battery dies. By then there will probably be features I want.
Podcast Episodes / Re: Episode #640
« Last post by BBBlue on Today at 03:32:24 PM »
Your experiment and post makes an important point.  The most important part of the heat transfer may very well be through the top.  Via the non-vacuum lid or simple conduction where the part of the vacuum vessel that holds liquid meets the outer part.  Lots of post here about the radiation across the mirrored vacuum surfaces internal to the thermos but that might not be all the important.

The radiant barriers and vacuum gap make a huge difference; it's the difference between a solid metal cup that you can't hold in your hand when full of coffee, and one that you can.

There is heat lost through the holes in the lid, the lid itself is not a great insulator, and as you say, the inner liner and outer shell are compressed together at the top, but while that allows for some additional heat transfer when considering the entire system, the radiant barriers and vacuum gap do a good job of minimizing the temperature at the surface where you hold the cup. See below. Some heat is conducted down the side from the compressed top rim, but doesn’t seem like much.

Here are some data to consider:

Ice water @ 30 minutes after filling: Ambient room temperature = 76°F; liquid = 32°F; top = 66°F; middle = 74°; bottom = 76°F.

Boiling water @ 30 minutes after filling: Ambient room temperature = 76°F; liquid = 191°F; top = 108°F; middle = 84°; bottom = 79°F.

20-oz Yeti tumbler. Top is the outside surface in the compressed area. Middle is midpoint of tumbler surface where one would normally grip it. Bottom is the surface just below the seam.

When gripping the cold water-filled tumbler, I get an instantaneous cooling sensation that goes away after a few seconds. If I don’t change my grip, it seems as if the surface in contact with my skin warms to something close to skin temperature.

When gripping the hot water-filled tumbler, I don’t get much of a sensation at all; doesn’t feel warm, feels sort of the same as when my skin warms the surface after holding the cold water-filled tumbler.

My perception is that there is an immediate transfer of heat from skin to cooler metal that registers as cool, but then my skin warms the metal surface it touches and temperature at that interface reaches equilibrium. When touching the middle of the tumbler filled with hot water, the surface is already close to skin temperature, so there is no sensation of temperature change.

I don’t think that delta-T is relevant because the tumbler seems to have been designed to be a better insulator for hot liquids compared to cold. The most important variable is simply what surface temperature results from the total system. I think the Yeti cups have been well engineered to keep hot liquids hot and comfortable to hold, and cold liquids cold while maintaining surface temperature above dew point found in what they consider average conditions for use.
Wife's grandma has the worst case of Alzheimer's you've ever seen... she's literally an empty shell of a body, living in a care home.  Grandpa covered for her until he died... 13 years ago.  She keeps hanging on, but she's functionally brain dead.

Anyway, wife sees it happening to her uncle... watches closely her mom... worries about herself.

I read that frontal lobe dementia doesn't cause memory loss - not trying to make comparisons in diagnoses... just in how we respond to them.
It is normal to swing between hope and despair when you get updates. Learn who you can rely on and just stay in touch to stay updated. There is not a lot you can do to Change the facts. They are so much better at diagnosing "dementia" but there are so many versions or causes, I would not be too worried about genetic factors unless it is clearly one with a marker; and if so, just get tested and be put at ease or on notice.

I've been through this with loved ones and helped a neighbor (her mother had Lewy Body dementia) and their end of life. It can actually be a bit fun, if you get over the tragedy and just follow the course this takes.

Phone call from Dad (while in a care facility in Southern California): "You need to get here right away and bring me $1,000. I don't have any pants and I am in jail in Alaska; I got into trouble with some girls."
Me: "Dad, look around; do you see your legs?"
Dad: "Yes, at the end of the bed."
Me: "Then, you're in bed, not in jail?"
Dad: "Yes."
Me: "Then, let's wait until you get better and I will bring your money, then, okay?"
Dad: "Oh, sure, that makes sense."

Me to my sister: "You know it means he got arrested for prostitution sometime while in the Air Force, and we never knew about it, right?"

We have a million of these stories, from his final 9 months. Turns out, though, he was showing signs of dementia for nearly 2 years or so, but hiding it well. A tour of his household effects revealed the truth.

To love them to the end, you do what you can and don't fret about what you can't. If you are not a mental health professional, then know your limits. That's how we found peace, as things progressed.

Podcast Episodes / Re: Episode #640
« Last post by kenhaley on Today at 03:06:39 PM »
It looks like others have already made my two points, so I'll be brief:
  • Room temperature metal feels cooler to the touch than it is.  Primarily because body temperature is higher than room temperature and metal (the outside of the thermos) is a good conductor.
  • Iced liquid doesn't go up in temperature as it absorbs heat until all the ice is melted.  And ice absorbs a LOT of heat as it melts.
I would call this a touch illusion, as opposed to an optical illusion. (Is there a better word for that?) The right way to do the experiment would be to measure the termperature change in the cold liquid (with no ice) over a given amount of time, and then repeat with a hot liquid for the same time period. I would bet that hot liquid will cool faster; because the temperature difference between it and room temperature is much higher.  The thermos's insulation ought to work equally well either way.
Games / Re: D&D Game
« Last post by random poet on Today at 02:55:46 PM »
Good point, and by that time Xanathar's Guide will probably be out, anyway.
Games / Re: D&D Game
« Last post by John Albert on Today at 02:47:56 PM »
There is a new barbarian path in Unearthed Arcana, which will be published soon in Xanathar's Guide, and it's the obvious choice for Punch. It's the Path of the Ancestral Guardian. Story-wise it relies on a barbarian's ancestors for guidance and protection. Mechanics-wise, it's a bit weaker than other paths, it seems, so maybe they will boost it in the official version, but I guess we can use the UA version for now?

Interesting. I'll allow it, but you need to make level 3 of Barbarian first.
Forum Games / Re: Visual Counting
« Last post by John Albert on Today at 02:46:28 PM »
they can only be repaired by licensed shops

This isn’t really true, for the most part.  Most parts on cars are still user-replaceable, and there are legal protections guaranteeing that manufacturers cannot void warranties for third-party and diy repairs.  There are some diagnostic tools that third-party mechanics don’t get access to, but that really just leaves them with a little more old-fashioned sleuthing.

Yeah, if there’s a failure in one of the electronic subsystems you may be better off seeing a dealer; but those systems are solid-state and so reliable that most people never need them repaired.

With subsystems, you can often pull the whole circuit and replace it with one from a junkyard.
Sometimes you can effectively replace every circuit in that manner instead of paying a shot to troubleshoot it.
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