Today I Learned

[Hornbein]

Is this a reasonably plausible roadmap to develop an explosives / drugs / gas leak detector:

Identify the receptor molecules that are involved when bees smell the target substance. Modify some bacteria so they produce those molecules. Find a way to get an electronic signal when the receptor molecules catch their target molecules.

Ref: https://www.sciencedirect.com/science/article/pii/S2214574523000159

Another possibility: based on recent progress in growing artificial tissue... Can we grow bee tissue (from stem cells or whatever) of the right type, then interface with it via microelectrodes?

Last time I looked (ten years ago?) the basics of the sense of smell were not understood. We don't know how it works.
.

 

[DaveC426913]

. . .you may not be getting the fish you order at a restaurant. Apparently, many restaurants think consumers are too dumb to know the difference between x-fish (more expensive) and y-fish (cheaper) and will substitute y for x.

*shakes head*

Trickery is everywhere. A family friend, I found out, cheated my parents when he & his crew built a fence for them. He charged them for cedar (which they requested, as it's a better wood), but used pine instead (substantiated by multiple knowledgeable sources). Took their money for a garage construction job also and only completed 75-80% of it and said would return to do the rest (never did and said he was too busy and told them to finish it themselves).

Cheaper substitutions. . .be wary.

This is so true! I once had a contract for a deck built of cedar, but when they finished it I found out they'd used pollock.

 

[kyphysics]

This is so true! I once had a contract for a deck built of cedar, but when they finished it I found out they'd used pollock.

Cheaters are everywhere. Sometimes, it's just very tough and/or exhausting to try to keep up with scams. Who has time (and/or knowledge) to look into all these fake/scam-ey/cheating situations?

Here is another construction/carpenter one. You agree to buy some materials:

dry wall
a crown molding
a pillar/post

The contractor buys it and gives you the receipt (Home Depot, Lowe's, etc.). Then, when he/she installs the actual item, they use a a different, cheaper one. SECRET: they bought these separately and have a separate receipt for them. They charged you for the expensive ones (which they bought also, but will not use), but then actually gave you a cheaper item. Afterwards, they return the more expensive items and pocket the difference.

The "trick" to this one is you think you got the real goods, b/c of the legitimate receipt for them.

Unless you demand the receipt and boxing for items AND have an EYE to spot differences, you could get taken.

Speaking of pollock, apparently scallops are one of the most faked items and one way is to use pollock fish instead:


Inside Edition's fake food series has me super angry and paranoid now. So many cheats out there!

 

[skynr13]

Yeah, but I've tried adjusting my personal aspect ratio and I'm STILL fat !

And that goes for sitting at the computer all day!

 

[skynr13]

Today I learned that "chasing the dragon" is slang for smoking heroin.

Jim Morrison speaks of 'Riding the Snake!'

 

[Janus]

TIL about "skiplagging". Apparently, it can sometimes be cheaper to by a ticket from Airport A to Airport C with a layover at airport B than it is to by a ticket for a direct flight to Airport B. So people wanting to go from A to B will by the layover ticket, and never take the second leg of the trip to C. Of course, the Airlines don't like it, as it leaves them with an empty seat from B to C that they otherwise could of sold.

 

[phinds]

I don't know about these days but it used to be true that some flights were cheaper for a round trip than for one way so folks who wanted a one-way ticket would buy a round trip and not use the return flight. Airline prices often don't make any sense.

 

[DaveC426913]

Of course, the Airlines don't like it, as it leaves them with an empty seat from B to C that they otherwise could of sold.

I don't know about these days but it used to be true that some flights were cheaper for a round trip than for one way so folks who wanted a one-way ticket would buy a round trip and not use the return flight. Airline prices often don't make any sense.

This is an indication of their profit margins.

If they charge, say, $1000 for a layover from A to C,
But they charge, say, $1200 for the direct flight,
That means the full flight from A to C (including all additional costs of the layover, let's say $200) costs less than $800.
Which means the cost of a direct flight is less than $800.
And that $400+ is straight additional profit.

 

[pinball1970]

TIL Something about a series. I am now very depressed about it.

 

[jack action]

Of course, the Airlines don't like it, as it leaves them with an empty seat from B to C that they otherwise could of sold.

But wasn't it already sold in the first place? If people buy tickets for a flight and 90% of the passengers don't show up, why would the company care if there are only 10% of the seats filled? It just means less fuel needed thus a bigger profit.

 

[gmax137]

This skiplagging has been in the news recently. The reports said that

• it is specifically prohibited by the "contract" you (apparently) agree to when you buy your ticket
• the airlines can ban you from future flights and confiscate your freq flyer miles

Why would they be so upset? I think mainly because it exposes the nonsensical pricing, where A to B ticket is more $$ than A to B to C. Imagine if bus fares worked this way. "Wait, you have to pay more to get off at this stop!"

 

[pinball1970]

TIL Nobel for physics 2023 is announced tomo

 

[berkeman]

TIL Nobel for physics 2023 is announced tomo

Europe is back on Standard Time already?

 

[Borg]

I don't know about these days but it used to be true that some flights were cheaper for a round trip than for one way so folks who wanted a one-way ticket would buy a round trip and not use the return flight. Airline prices often don't make any sense.

I don't think that this happens as much anymore but I have used it in the past. My wife was overseas once and needed to come home. She couldn't understand why I bought her a round-trip ticket. It took a bit of explaining to assure her that I did not buy a more expensive ticket and that yes, the round trip version was cheaper.

 

[Hornbein]

Suppose your itinerary is A to B to C to D. Often the ticket from A to D is less than B to C.

 

[phinds]

Suppose your itinerary is A to B to C to D. Often the ticket from A to D is less than B to C.

As I said

Airline prices often don't make any sense.

 

[Ibix]

it is specifically prohibited by the "contract" you (apparently) agree to when you buy your ticket

I really struggle to imagine a contract term saying "you paid for services A and B, and if you only use A we can punish you" being enforceable. Doesn't mean they don't write such a term, of course, and challenging one might be more risky than it's worth.

Why would they be so upset?

I think they may have to request fuel volumes before they know people haven't turned up. So they end up carrying more fuel than they need, which is more delay during refueling and more weight in flight (and therefore fuel use) than they need. If no-showing is particularly rampant they may have more flights than they need, and/or more staff on duty.

It all stems from their bizarre pricing structure, of course, but large scale no-shows probably do cost them money.

 

[Borg]

Airlines do account for this by overbooking flights and selling more seats than the plane holds. Usually it works pretty well for them but sometimes they have to explain it to irate passengers who expected that they had a confirmed seat assignment and are suddenly being bumped from the plane.

 

[DaveC426913]

I really struggle to imagine a contract term saying "you paid for services A and B, and if you only use A we can punish you" being enforceable.

Yeah, go check out my thread on phones and services.
You want a 2-year contract? Here's an almost free phone.
Oh, you just want the phone? That's $1000.

 

[jack action]

So they end up carrying more fuel than they need, which is more delay during refueling and more weight in flight (and therefore fuel use) than they need. If no-showing is particularly rampant they may have more flights than they need, and/or more staff on duty.

But I already paid for that fuel and that staff. The plane is still lighter by my weight - and my baggage - missing and the staff can give a better service to the other passengers.

Imagine you buy tickets for an entire airplane and don't show up. The entire staff is there and the fuel tanks are full. The plane is empty and leaves anyway ... because they were paid to do so. Not only they won't lose money (the ticket buyers do) but they will use less fuel overall, have no meals to serve, etc. so a slightly larger profit overall. Sure, they could have made more if they had not hired the staff and filled up the tanks, but they cannot lose any if they priced their fare right from the beginning.

 

[Ibix]

But I already paid for that fuel and that staff.

Sure - I should have said "they spend more money than they needed to".

I'm not defending them. Their pricing system is stupid.

 

[pinball1970]

Europe is back on Standard Time already?

UK on BST till 29.10.23

 

[berkeman]

UK on BST till 29.10.23

What does it change to then? British Daylight Time?

 

[DrGreg]

What does it change to then? British Daylight Time?

Greenwich Mean Time.

 

[berkeman]

Oh wait, S=Summer over there, not Standard. Got it. (TIL)

https://en.wikipedia.org/wiki/British_Summer_Time

 

[Hornbein]

If the airline can intimidate/coerce you into buying a one way ticket for more money than the round trip then they make more money. It is a rational profit-maximizing practice.

 

[Hornbein]

TIL I learned that during a 1989 concert Peter Townsend impaled his right hand on the whammy bar of a Fender Stratocaster. When right through his palm. The doctors told him he was very lucky to avoid permanent damage. He was able to continue the tour.

 

[pinball1970]

TIL Nobel for physics 2023 is announced tomo

No sound yet. Love the fact they just sit on the floor like students. Cant remember the last time I sat on the floor, probably when I was a student.

 

[Hornbein]

No sound yet. Love the fact they just sit on the floor like students. Cant remember the last time I sat on the floor, probably when I was a student.

In Tokyo concerts for young people often have no chairs, just a concrete floor. This allows more people to be packed in there, and sometimes they are indeed packed with maybe a thousand viewers. I can't stand up on concrete that long so I'd resort to the floor.

 

[Hornbein]

Today I learned that it appears that redheads need more anaesthetic. https://www.healthline.com/health/redheads-and-anesthesia

Anesthesiologists are starting to take this into account but are doing so naively. They may overly dose patients with hair dyed red and underdose redheads whose hair has turned grey.

 

[pinball1970]

Foot prints found in Utah. Thought to be human and 12,000 years old.

https://news.cornell.edu/stories/2022/07/ice-age-human-footprints-discovered-utah-desert

 

[DaveC426913]

Foot prints found in Utah. Thought to be human and 12,000 years old.

https://news.cornell.edu/stories/2022/07/ice-age-human-footprints-discovered-utah-desert

Come on. The oldest human in the world is barely 120.

 

[pinball1970]

Come on. The oldest human in the world is barely 120.

 

[jbriggs444]

I really struggle to imagine a contract term saying "you paid for services A and B, and if you only use A we can punish you" being enforceable. Doesn't mean they don't write such a term, of course, and challenging one might be more risky than it's worth.

I think they may have to request fuel volumes before they know people haven't turned up. So they end up carrying more fuel than they need, which is more delay during refueling and more weight in flight (and therefore fuel use) than they need. If no-showing is particularly rampant they may have more flights than they need, and/or more staff on duty.

It all stems from their bizarre pricing structure, of course, but large scale no-shows probably do cost them money.

I believe that it is a mechanism to "segment the market". It is part and parcel of other mechanisms aimed at the same goal (advance purchase, standby fares, weekend and holiday rates, round trip around a weekend). In general, you want to give price breaks to the passengers who are price sensitive or are shopping around and not give price breaks to passengers who are not price sensitive or have no choice.

The classic case is an airline that has a hub in B. They have no or few competitors in B.

The airline can charge high rates for a flight from A to B. They are the only carrier that can service the route. But when taking passengers from A to C, another carrier with a hub in B' (B prime) can compete. The airline must reduce its fare or lose business.

In this case "segmenting the market" means locking A to B passengers into the A to B fare while allowing A to C passengers to use the lower A to C fare.

 

[Hornbein]

I believe that it is a mechanism to "segment the market". It is part and parcel of other mechanisms aimed at the same goal (advance purchase, standby fares, weekend and holiday rates, round trip around a weekend). In general, you want to give price breaks to the passengers who are price sensitive or are shopping around and not give price breaks to passengers who are not price sensitive or have no choice.

The classic case is an airline that has a hub in B. They have no or few competitors in B.

The airline can charge high rates for a flight from A to B. They are the only carrier that can service the route. But when taking passengers from A to C, another carrier with a hub in B' (B prime) can compete. The airline must reduce its fare or lose business.

In this case "segmenting the market" means locking A to B passengers into the A to B fare while allowing A to C passengers to use the lower A to C fare.

I flew from Guangzhou to Hong Kong to Seattle to Salt Lake City. ABCD. There are plenty of airlines flying from Hong Kong to Seattle [BC] but these are more expensive than Guangzhou to Salt Lake City. [AD}. I think the higher price is because demand is higher and because Hong Kong and Seattle residents have more money than Guangzhou and Salt Lake City travelers.

Airline pricing is done by big computer programs that take all sorts of things into account. They maximize Hong Kong-Seattle income then fill the remaining seats with lower cost connecting flight travelers.

 

[sbrothy]

"Of the 20 rats examined, eighteen of them showed a preference for Beethoven, and only two showed a preference for Miles Davis. "

The rats preferred silence to Beethoven's Fur Elise. The scientists considered making music that the rats liked but have yet to explore this avenue. They noted that music has an effect on the human brain similar to popular forms of drug abuse. They were able to get the rats to prefer Beethoven over silence by injecting them with a cocaine solution in association with Beethoven's Fur Elise.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3144275/

Hipster rats : Outnumbered!

View attachment 321728

Sometimes you hear these horror stories about drugs that if you put a rat in a cage with no access to PE and females they'll get addicted to morphine (wow, really?!). That's why I like this study.

Rat Park (wiki)

It doesn't say anything about musical preferences though.

 

[Hornbein]

Wire was first made five thousand years ago.

In some cases, strips cut from metal sheet were made into wire by pulling them through perforations in stone beads. This causes the strips to fold round on themselves to form thin tubes. This strip drawing technique was in use in Egypt by the 2nd Dynasty (c. 2890 – c. 2686 BCE[2]). The oldest record of wire being made for musical instruments is from Augsburg in 1351. -- Wikipedia

I thought it would be very hard to do, but apparently not.

 

[Ibix]

Airline pricing is done by big computer programs that take all sorts of things into account. They maximize Hong Kong-Seattle income then fill the remaining seats with lower cost connecting flight travelers.

...and it's probably easier to issue legal threats to people than change the algorithm to close the loopholes.

 

[gmax137]

TIL that Physics Forums is on Facebook. Here's a screen shot

 

[BillTre]

TIL that Steve Miller has turned 80.
He has made a bunch of good tunes.
Here is one of many:

 

[gmax137]

TIL that Steve Miller has turned 80.
He has made a bunch of good tunes.
Here is one of many:

80, wow! Time moves swiftly in this place.

I liked their earlier trippy blues tunes, like this:

 

[berkeman]

This is interesting, and a nice advance in technology, IMO. Tonight I was watching an episode of COPS where they used a new portable instrument called "TruNarc" to test a small plastic baggie of suspected narcotics. The TruNarc uses a laser to illuminate the sample (even through the clear baggie, no need to extract a sample), and analyzes the reflected light to determine if the substance is a match for illegal narcotics.

Pretty nice step forward, IMO. I'll need to read more about it to understand the technology used and its limitations.

From TV tonight:

And from a web search:

https://www.thermofisher.com/order/catalog/product/TRUNARC

 

[Hornbein]

Red Bull was invented in Thailand. In the early days it was banned in Germany.



In Indonesia energy drinks that contain caffeine and nicotine are sold to children mixed with candy. I tried that. I got a case of paranoia until the drug wore off.

 

[DaveC426913]

This is interesting, and a nice advance in technology, IMO. Tonight I was watching an episode of COPS where they used a new portable instrument called "TruNarc" to test a small plastic baggie of suspected narcotics. The TruNarc uses a laser to illuminate the sample (even through the clear baggie, no need to extract a sample), and analyzes the reflected light to determine if the substance is a match for illegal narcotics.

What? Hard-nosed cops won't rip the bag open, dunk their pinkie in an unknown powdery substance and taste it anymore??

What a world, what a world.

 

[BWV]

 

[Borg]

I'll drink to that!

 

[Rive]

What? Hard-nosed cops won't rip the bag open, dunk their pinkie in an unknown powdery substance and taste it anymore??

Fentanyl

There was some viral videos about secondary fentanyl poisoning cases among cops, but so far those are widely considered fakes
But that won't change the fact that since fentanyl hit the streets tasting unknown suspicious stuff is even less of a good idea than ever before...

 

[pinball1970]

View attachment 333137

I had to read it twice! I read solar system and thought galaxy!

 

[pinball1970]

Fentanyl
View attachment 333138
There was some viral videos about secondary fentanyl poisoning cases among cops, but so far those are widely considered fakes
But that won't change the fact that since fentanyl hit the streets tasting unknown suspicious stuff is even less of a good idea than ever before...

I always thought that was very dodgy.
No way to tell what this white powder is, could be cocaine so lets taste some...what could possibly go wrong?

 

[DaveC426913]

I always thought that was very dodgy.
No way to tell what this white powder is, could be cocaine so lets taste some...what could possible go wrong?

I only know of it from films and TV shows, and i suspect that goes for all of us.

I did read somewhere a real cop saying it is a ridiculous cliche that no sane cop would ever do.