John Cuthber

Apparently the problem is that you don't understand a hypothetical situation. But yes, it does explain a lot

At that point I called the local hospital and had myself admitted to diagnose the mental health issue.

Thanks for letting me know that the microscopes I worked on in which electrons tunnelled giving a map of the surface electron fermi potential were not electron microscopes. I'm not going to build a tunnelling proton microscope. It's possible, but much easier to use electrons. Which is why scanning tunnelling electron microscopes are, in fact, electron microscopes. (Wiki is not God) These are electron microscopes too. https://en.wikipedia.org/wiki/Field-emission_microscopy They don't have electron guns (in the definition Sensei posted) But they are tunnelling microscopes. The field emission relies on tunnelling. Somehow, I think the folk who designed scanning electron microscopes where pretty much the only "moving part" was an electron beam, knew what they were doing.

I wasn't aware that anyone had said that STM and SEM were the same. Can you point out where they did so? I obviously know they are different, you may recall that I pointed out that you can run one of them under water and that it doesn't have an electron gun. The OP just said "electron microscopes". That term includes TEM, STEM PEEM and SEM. If I was an amateur trying to build an electron microscope, It'd build a tunneling one. (No high voltages, no vacuum chamber and also past experience of helping rebuild one about 1990)

Is that a reference to this? Thankfully, not all electron microscopes use an electron gun. The requirement for a vacuum is last century's technology. https://www.sciencedirect.com/science/article/abs/pii/0006291X91910328 Calling the newbies "silly" is a nice example of this. But to be fair this is correct; just like I said.

I'm sorry you expressed yourself so badly. The answer to your question is "it depends". There's several types of electron microscope and they use a variety of methods to form an image. If you haven't figured out how to see that then I'm right. You haven't figured everything else out.

If you think the shape of the electrons matters, then I very much doubt you have figured everything else out.

It's not a bad bet that the original apples were similar to what we call crab apples. If they always bred true then they would still be crab apples. It's important to distinguish the level of "sameness" that people seem to want in apples from that which they would get in nature. For a lot of things, plants which are effectively siblings are close enough, but for our apples we want identical twins. There's a half-way house where we grow F1 hybrids for use. So, for millennia our ancestors chose the biggest sweetest apples and in due course those apples' seeds were "planted" near human habitations (and well fertilised too). So the treed that grew from them were biased in favour of big sweet apples and the offspring were subject to the same sort of pressure. No need for Adam or Eve to understand genetics. Once we started farming, we deliberately chose seed from plants that we liked. But we discovered that apples don't breed true and they take ages to grow so it's a slow process to take pot-luck. We found it's much more efficient to clone them.

Here's a list of varieties produced from Cox's orange pippin which were obtained by breeding them with other varieties. https://en.wikipedia.org/wiki/Cox's_Orange_Pippin#Descendant_cultivars One example is Allington Pippin (Cox's Orange Pippin × King of the Pippins) But it's important to realise that, if you fertilised flowers of one with the pollen of the other and grew the pips there's still no guarantee that the seeds would grow into anything like the Allington Pippin for essentially the same reason that you and your brother or sister are not identical. Apples (and a lot of related fruit) are self-incompatible. You can't get seed from a Cox's orange Pippin without crossing it with another variety. So you can't raise them from seed. If native varieties all bred true there wouldn't be any cultivated varieties. If you are growing commercial apple trees there are no generations. There are no seeds; it's all cloning. And that's where we get the word "clone" from from Greek klōn ‘meaning twig’.

I can believe you, or I can believe wiki " while fruit varieties such as apples have been propagated over the centuries through grafts and cuttings. " And I know that fruit trees won't "breed true".

Mary had a little lamb. Her father shot it; dead. But still it goes to school with her Between two bits of bread.

I don't see why it couldn't work. They commonly use quince stocks for pears https://www.orangepippintrees.co.uk/articles/fruit-tree-gardening/rootstocks-for-pear-trees

The root stocks are also propagated from cuttings- for the same reasons as the top bits. I gather that you can graft pears, apples and quinces onto the same tree. I'd like to know if you can do it with these fairly closely related plants https://en.wikipedia.org/wiki/Buddleja_davidii and https://en.wikipedia.org/wiki/Buddleja_globosa Because the clash between the orange and purple flowers would be hideous.

Those trees are almost certainly grown from cuttings. The word "heirloom" in this context means that they are a very old variety. https://en.wikipedia.org/wiki/Heirloom_plant

I think it was assessed here And the consensus was that it's crazy. I don't think there has been any improvement since.

To a good approximation, weigh the jack. Find jacks of similar design on the net and then look for one that weighs the same.

I'm pretty sure someone has the maths for things with a smooth change in refractive index. https://en.wikipedia.org/wiki/Gradient-index_optics

I did not say that no effect exists. I said that if there was a big effect, we would know about it.

If you didn't allow any people near the robot, you wouldn't need to worry about them saying "stop". A policy which may have other benefits... In this situation, you could use a passive IR sensor like they use in burglar alarms. If there is a person in the room, you shut down the robot.

Is that why you answered a post on double displacement reactions without there being anything related to double displacement reactions in your reply?

If your batteries are nearly on fire you will get some H2S. The academic book doesn't seem to mention batteries. I'm reminded of the story of the Kursk, where the official news said lots of things...

That does not make much sense.

That's not true. It is considered as a risk factor in humans https://en.wikipedia.org/wiki/Metronidazole says "In 2016 metronidazole was listed by the U.S. National Toxicology Program (NTP) as reasonably anticipated to be a human carcinogen." and "Metronidazole is listed as a possible carcinogen according to the World Health Organization (WHO) International Agency for Research on Cancer (IARC)" It plainly is considered to be a cancer risk. Similarly Says who? That paper is from 2018 by which time MTZ had been listed as a carcinogen for 2 years or so. Is anyone saying it's not carcinogenic?

No.

The National Trust is responsible for some bits.