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May 26

Train question

New York City's fastest intracity trains (the long downhill to Roosevelt Island at low traffic) feel faster and awesomer than they are (especially when standing at the front window). Cause: 1. You look through a loose sliding door that always sort of slams once per shore cause all 4 have a ventilation shaft and the train's like a piston. 2. you can feel the wind though the gaps, the penetration causes extra wind noise/whistling. 3. the entire train shakes so fast it makes it feel like you're hauling ass. So I'm wondering if this happening at only 55 mph would be considered quaint by British Isles standards or normal? Sagittarian Milky Way (talk) 07:35, 26 May 2022 (UTC)[reply]

Well, what is considered is specific to each individual, but for myself I'd consider it quaint: I haven't experienced anything like that on, for example, the London Underground system (much of which is actually not underground) for a couple of decades, but I don't regularly travel on all the different lines, so Others' Mileages May Differ (literally). Metro systems in other British cities are newer than most of the LU (not all – see Elizabeth line), so have more modern stock. {The poster formerly known as 87.81.230.195} 90.209.235.54 (talk) 08:54, 26 May 2022 (UTC)[reply]

The new Elizabeth Line trains have a maximum speed of 90 mph but will not normally operate above 60. [1] However, the average speed on the rest of the network is only 20 mph, [2] often because the stations are only a few hundred yards apart in central London, and the older lines in the world's first underground railway can be very rattley and sometimes screech horribly on tight curves. Although the infrastucture is often old the rolling stock is regularly updated and nearly all has been replaced in the last twenty years. Alansplodge (talk) 11:25, 26 May 2022 (UTC)[reply]

I'm jealous (maybe I wouldn't be if I lived in Reading), in the States 90 mph would break the train speed limit by at least 10 mph almost everywhere. According to Google the Underground itself also reaches 60 mph or 100 kph in the northern Metropolitan Line. The only American trains >80 mph might still be Northeast only. Cause expensive track quality improvements are needed and the long-distance 80 mph trains are already subsidized (low ridership). We also have one high-speed line (between New England and Virginia(ish?)) that briefly does ~150 mph in the less busy north of NY part but usually 120 or less. According to the article box NYC subway avg speed is only 17.4 mph, sometimes there's men working in the day and the trains have to slooow to a crawl, the paranoia about experienced drivers accidentally hurting experienced subway workers with a train they heard and saw from light-years away is ridiculous. Like everyone's on the other track side of a dense line of columns and they still have to go honk-honk at c. 2-4 mph for longer than his train is passing the workers. Lots of the NYC subway rolling stock was still built in the 1970s and 80s though the 21st century percent is getting higher with each train model retirement, 67% of NW trains are 44-47 years old and the rest are at least 33. The 60th Street Tunnel opened 1920 but I doubt 1920 rails are still there, especially if this is one of the many tubes flooded by the hurricane. The tighter curves do that here too, the smallest radius is only 95 feet though that line has to use unusual short wide cars cause the long wide ones won't fit and only employees are allowed on the short narrow ones. Sagittarian Milky Way (talk) 01:13, 27 May 2022 (UTC)[reply]

Just because I like rubbing it in (:grin:), the 31 mile Channel Tunnel is used by the British Rail Class 373 "Eurostar" trains which can reach speeds over 180 mph (and have exceeded 200 mph as a record setting run). Within the tunnel itself they are restricted to a mere 100 mph, but the track is engineered for eventual 120 mph running. OK, not intracity, but still running in tunnels! Martin of Sheffield (talk) 13:57, 27 May 2022 (UTC)[reply]

Hopefully the Northeast Maglev isn't delayed till I'm too old to ride it. Japan's building a mostly underground maglev, it'll probably become the world's fastest passenger train in a tunnel. Sagittarian Milky Way (talk) 02:02, 28 May 2022 (UTC)[reply]

The Elizabeth Line is also not part of the London Underground (Metro) system, it is part of the greater Transport for London system, but is a commuter rail line and not integrated with the Underground system. --Jayron 32 13:43, 26 May 2022 (UTC)[reply]

Well - there are 8 stations where you can change from the Elizabeth line to an underground line, so it is as integrated as all the other underground lines.--Phil Holmes (talk) 14:08, 26 May 2022 (UTC)[reply]

There are, but the EL is being run as a separate service, AFAIK, it is run under TfL Rail and not as a line of the Underground, though I may be mistaken. --Jayron 32 14:11, 26 May 2022 (UTC)[reply]

Furthermore the Elizabeth Line runs British Rail Class 345 Aventra trains which are to BR loading gauge and using 25 kVAC overhead, unlike the tube trains which are to a smaller loading gauge and use third and fourth rails at +420 and -210 VDC. Signalling is via the ETCS system, though at what level I'm not entirely sure, whereas the traditional tube is signaled by absolute block and colour light signals. The Elizabeth line runs out to Reading, which by no stretch of the imagination is London. Martin of Sheffield (talk) 14:40, 26 May 2022 (UTC)[reply]

Indeed, most commuter rail lines have shared stations with metro stations that allow transfer between the systems, but are not strictly part of the metro system in question. For example, VRE and MARC each have several shared stations with the Washington Metro, likewise MBTA Commuter Rail shares several stations with MBTA subway in Boston, indeed most of the rail systems I have had experience with often run like the Elizabeth Line; with several shared stations existing in the urban core between commuter rail and rapid transit. It doesn't make such services not commuter rail, and they are distinct from the urban-core rapid transit systems they interact with. As I said, not being a Londoner, I don't have experience with the Elizabeth Line, but my understanding is that while it does have some common stations with the Tube, that the two are separate systems. --Jayron 32 17:49, 26 May 2022 (UTC)[reply]

Back to the original question. Sagittarian Milky Way, I assume that you are talking about the Roosevelt Island Tramway, although I could be wrong. If so, that is not a train but instead an aerial tram. The top speed is 16 miles per hour. Cullen328 (talk)

No, they said the N/W, aka the Broadway train. The N/W trains cross (but do not have a station on) Roosevelt island between Lexington Avenue/59th Street station and Queensboro Plaza station. You can see it as the yellow line here. This is the 60th Street Tunnel, which as noted, trains can traverse at up to 45 mph. I've not ridden the line, but given the large elevation changes between Manhattan and Roosevelt Island (which is evident when you cross the Queensboro Bridge; the deck of which is essentially level with the 2nd Avenue onramps in Manhattan, but which is quite high above Roosevelt Island), it makes sense that there would be such a steep incline in the underground subway line. --Jayron 32 18:11, 26 May 2022 (UTC)[reply]

Maybe the average speed of the whole tunnel is 40-45 mph (or at least when unrestricted by traffic lights the whole way, theoretically the train ahead could panic stop at any time and the train behind could run a double red light as fast as the laws of physics allow and the un-overide-able automatic brakes will prevent contact/crash yet drivers seem to be required to tap the brakes or throttle ASAP at even the caution light that the light ~0.15 miles ahead isn't double green, not even close to double yellow or red and yellow or green and yellow yet). However a train driver has told me this is the fastest place in the system and they reach 55 mph. Train forums say 65 mph can happen there on the driver's speedometer but also say old NY subway speedometers are trash (newest old trains are ~1990, even 1964 trains ran till mid-COVID). The west station is dozens of feet above sea level, it drops steep (by subway standards) to 150 feet below sea level or almost (could be lowest point in the system but I don't know exact figures) and the other end of the straight is also dozens of feet above sea level (and about 2 storeys above ground). Sagittarian Milky Way (talk) 01:13, 27 May 2022 (UTC)[reply]

I remember from last time I visited London (december 2016) a ride on the Jubilee line (you know, those trains that are so full in the rush hour that you can't sit and are so low that tall people can't stand either, so you have to fold yourself over and squeeze yourself into some corner) from London Bridge to Stratford. The train had rattling doors, some wind coming in and an awful noise, but maybe it was just that particular train that needed new door seals. The much larger trains on the District line gave a nicer ride.

As to why, I can think of a few reasons. Stations are very close together, with all curves and pointwork inbetween, so those curves tend to be sharp. At the same time, the trains must be fast and have a quick acceleration, or people wouldn't use them or capacity would be too low, so that's why you feel such large accelerations in all directions, giving the impression of high speed. Also, as the margins around the loading gauge are fairly small, the trains must have rather stiff suspension, or the body of the car could hit the tunnel wall or platform. This also increases the shaking. And nobody cares for comfort on such short rides. PiusImpavidus (talk) 18:36, 26 May 2022 (UTC)[reply]

Those seem like good explanations, the V-Tec just kicked in yo part only lasts c. half minute, not the days of nationwide trains (I wonder if hunting oscillation is involved too, as it strengthens rapidly in a handful of mph). However there are no curves between these two stations except a lane change-shaped curve right after/before the east stopping location to bypass the road bridge that the east station trains are aligned with. Excluding this there are approximately 1.45 miles of forward progress with no part of the train bent. Sagittarian Milky Way (talk) 01:13, 27 May 2022 (UTC)[reply]

The London Borough of Hackney, despite adjoining the City of London and therefore being one of the core inner London boroughs, has no underground stations and a paltry few yards of underground railway. There is continuous agitation to bring the tube to Hackney. Many years ago it was suggested that Dalston Junction railway station be reopened as part of the tube network. Transport for London's response was that this would never happen - it would reopen, but as part of a new "London Overground" network. Boris Johnson travelled to Dalston to open it. The Overground was formed when TfL took over the running of suburban rail services from private companies. The stations were handed over as well. Two services were not handed over to the contractor who runs the service for TfL - Paddington to Heathrow and Reading and Liverpool Street to Shenfield. They were given to a specially-formed company, TfL Rail, and the reason for that was that they would eventually become part of the planned Elizabeth Line. Our article notes "On 24 May 2022, upon the opening of the Crossrail central section, TfL Rail was rebranded as Elizabeth Line and the name was discontinued." — Preceding unsigned comment added by 92.19.175.5 (talk) 12:19, 27 May 2022 (UTC)[reply]

The Madonna economy

Hi Folks!! Can somebody tell me whether this is genuine or a hoax, i.e. could they review and tell me if they think it is genuine, if they have some time available. Thanks. scope_creep^Talk 14:53, 26 May 2022 (UTC)[reply]

Well, the article is correct in as much as a few scholars seem to have used the term 'Madonna economy' to describe aspects of 'cultural globalization'. So no, it isn't a hoax. Whether an obscure term like this actually merits a Wikipedia article is another question, though probably one better asked elsewhere - probably starting on the article talk page. AndyTheGrump (talk) 15:03, 26 May 2022 (UTC)[reply]

Some of the verbiage in that article looks like it was written by a non-English speaker. --←Baseball Bugs ^{What's up, Doc?} carrots→ 19:02, 26 May 2022 (UTC)[reply]

So it not hoax then. I'll try and find out if it translated. I can't make heads nor tails of it. No clue. scope_creep^Talk 21:47, 26 May 2022 (UTC)[reply]

Apart from being written badly, the article seems to be more about the term itself than about what it stands for, which is only acceptable if the term itself has been the subject of significant coverage. I have somewhat edited the lead, whose first sentence read as a DICTDEF. --Lambiam 08:00, 27 May 2022 (UTC)[reply]

Public health question - std screening programmes

Why is it that most public health authorities in most countries only have routine sexual health screening programmes for chlamydia, gonnorhea, HIV, Syphilis and Hepatitis (for certain groups of people). Why don’t they include the many other STDs which have serology, urine or swab tests available? What is the public health reasoning for this? Clover345 (talk) 15:57, 26 May 2022 (UTC)[reply]

Testing takes time and money to deliver, and false-positive results impose additional costs and stress (not to mention the potential hazards of unnecessary treatment) on the patient. Consequently, screening programs tend to concentrate on testing for diseases that have some combination of meaningful prevalence and patient or societal impact. If patients present symptoms (or are aware of potential exposures) that aren't addressed by a basic STI screening panel, appropriate medical professionals can order additional specific tests.

It's difficult to speak more specifically than that without considering particular jurisdictions and programs--did you have any in mind? TenOfAllTrades(talk) 16:16, 26 May 2022 (UTC)[reply]

I was thinking of the more well known programmes such as by the CDC in the US or by the NHS in the UK. Clover345 (talk) 16:44, 26 May 2022 (UTC)[reply]

Because the CDC and the NHS have limited resources, and tend to focus on STIs that are either the most prevalent, or the most dangerous, or some combination of the both. STIs that either a) have a relatively inconsequential impact on the patient's quality of life or b) are exceedingly rare and hard to transmit may be left off of the standard screening programs. Resources are not infinite, and need to be efficiently used in ways that make them the most impactful. --Jayron 32 17:41, 26 May 2022 (UTC)[reply]

As an aside, does the CDC even operate STI screening programs? My understanding is that they make recommendations as to which screening is appropriate, but that the CDC isn't usually directly involved in the delivery of health services. Most screening in the United States is, AFAIK, delivered by state and local bodies. TenOfAllTrades(talk) 18:06, 26 May 2022 (UTC)[reply]

They do track statistics on select STIs: see here, where data on chlamydia, gonorrhea, and syphilis is posted, and a separate page on viral hepatitis, some of which are STIs, and HIV here. They do have other pages broadly on other STIs, such as herpes, but do not maintain national statistics on these. --Jayron 32 18:26, 26 May 2022 (UTC)[reply]

Moreover, even with unlimited resources, the societal harm of false positives may exceed the benefits of finding true positives. --Lambiam 07:20, 27 May 2022 (UTC)[reply]

For instance, see breast cancer screening and prostate cancer screening. If you can read French or run a translation tool, here is a good 2016 post from a French doctor on the subject. Clearly that is not a WP:MEDRS source, but she explains with outstanding pedagogy the various statistical tricks and biases that make it hard to know if large-scale screening is desirable or not. Tigraan^{Click here for my talk page ("private" contact)} 09:40, 1 June 2022 (UTC)[reply]