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July 7

Cell phone radiation.

New article came out about cell phone radiation and brain tumor. https://www.fox32chicago.com/news/new-uc-berkeley-study-draws-strong-link-between-cell-phone-use-and-cancer But I have 2 questions, is phone radiation from smartphones different than from flip phones? (These articles don't seem to ever make a distinction.). And is it different when the phone is on a conversation, vs. not on a conversation? Thanks. 67.165.185.178 (talk) 15:53, 7 July 2021 (UTC).[reply]

Phone on a conversation is definitely different from phone not on a conversation. That how the system works, you have to broadcast more when you are actually using the phone. Otherwise, it only has to ping the next tower nearby.

Use of smartphone vs. flip phone is relevant if you are using a different cellphone network standard (3G, 4G, 5G), which might be the case or not. Different phones might also induce a different use. Say, you hold your smartphone away from your ear to see the screen, use hands-free mode if it works well, or you use a headset. --Bumptump (talk) 16:29, 8 July 2021 (UTC)[reply]

Okay I have a 2nd question: smartphone also uses the radiation for Internet, that flip phones typically do not have? So is putting your head next to a smartphone that is using the Internet, comparable to putting your head near a laptop using wireless connection? Or is that still different radiation? 67.165.185.178 (talk) 19:24, 8 July 2021 (UTC).[reply]

4G, which is pretty standard for smartphones, uses LTE frequency bands. There are different bandwidth assigned depending on country.

WLAN, which is basically how we all connect wirelessly to our routers, most commonly uses the 2.4 gigahertz and 5.8 gigahertz bands. Each range is subdivided into a multitude of channels.

There are innumerable devices, besides wifi and 4G, using some share of the the radio spectrum: baby monitor, wireless speakers, toys, car alarms, garage remotes, radios proper, cordless phones, GPS, Bluetooth. The bandwidth they use is not only a technical question. They are licensed to work only within a certain range of frequencies. And they are regulated differently in different countries. But yes, in a specific country WLAN and 4G should have a different bandwidth. Bumptump (talk) 20:47, 8 July 2021 (UTC)[reply]

What is meant by uplink, downlink, and duplex spacing, columns, in the LTE_frequency_bands you posted? 67.165.185.178 (talk) 08:10, 10 July 2021 (UTC).[reply]

Uplink and downlink are explained on the notes A2 and A3 at the top of the columns - uplink is the frequency that the base station receives on, and downlink is its transmit frequency. Duplex spacing is the frequency gap between the uplink and downlink - which a little arithmetic makes plain.--Phil Holmes (talk) 09:30, 10 July 2021 (UTC)[reply]

Note that the current scientific consensus is that cell phone radiation has no health effect (except for heating effects). Scientific consensus can change but this is an area that has been well-studied so a single publication would need to be of outstanding quality to overturn it.

The actual publication from the OP's news report is hard to track down but I suspect it is this one. Being a MDPI journal is not a great look: while some MDPI journals are serious, the parent company practices predatory publishing, so unless you are in the field it is hard to know if the journal they published in is legitimate.

I started reading the methods of the actual article and found the criteria for the selection of primary studies a bit shaky ("Disagreements between the two authors were resolved by discussion." is not how you do reproducible research). But then I thought of reading the two comments on the article and they make clear the meta-analysis is actually crap. There is some politics (about whether studies funded by the cell phone industry were conducted appropriately to avoid influencing the results) but even if you decide to exclude industry-funded studies you need to evaluate the other studies critically. Tigraan^{Click here for my talk page ("private" contact)}

July 8

Large ship fuel efficiency

How does the fuel efficiency of lake freighters compare with that of ocean freighters? Per tonne-kilometre/ton-mile, of course, since I assume the lake freighters are smaller because they don't need to be self-sufficient over the vast distances of the oceans. I found occasional resources that look at the fuel efficiency of lake freighters, e.g. [1], but unless I'm overlooking something, I didn't find enough numbers to calculate what I'm looking for. On one hand, an oceangoing ship can go wherever it wants to take advantage of good weather (cf. Trade winds#History) or avoid bad weather, while the size of the Great Lakes means that a lake freighter can't do that, and ships in the ocean can use currents (cf. Ocean current#Economic importance), while a lake freighter speeded by going downstream in the St Lawrence River has to fight the same current when returning upstream. But on the other hand, lake freighters only need to carry a small amount of fuel to reach their destinations, while oceangoing ships must use extra fuel to carry around the weight of the fuel that they need to reach their destinations. Nyttend backup (talk) 16:36, 7 July 2021 (UTC)[reply]

I haven't got exact numbers, but looking at engine power (which is a measure of fuel usage) and cargo capacity, both of which are mentioned on the infoboxes of many ships' articles, we can get a rough estimate. I looked at the numbers of MV Edwin H. Gott and Ever Given. Assuming the ships normally run at close to full power and have an engine efficiency of around 60%, and assuming bunker oil provides around 40GJ/m³, both have a daily fuel consumption of about 0.1% of their cargo capacity. The ocean-going ship is faster though, as is usual for container ships compared to bulk carriers, so per ton-kilometre it's more efficient. Despite going faster, which increases drag.

Carrying enough fuel to reach the destinations doesn't appear to be a problem for either of them. Carrying the fuel to cross an ocean only takes a few percent of their cargo capacity. There are other reasons why ocean going freighters are larger than lake freighters. Larger ships have less drag compared to their displacement, making them more efficient. Lake freighters cannot be that large, because:

The largest ships only fit in a few ports. Ports are only made large enough for these ships if their cargo volume is huge, which is when they serve as a hub for a substantial part of a continent: Tianjin, Singapore, Rotterdam, Los Angeles, some others. As the North American Great Lakes cannot be reached by large ocean-going ships, they cannot serve as such a hub, so the ports can only handle modest ships.
A low cargo volume means that, using large ocean-going ships, a port would be visited by few ships. This means that the cargo has to wait in port for a long time before a ship arrives to pick it up.
On long distances, travel time is important. On shorter distances, loading time gets more important. Smaller ships (and the same applies to other modes of transport) allow for faster loading, as there's less to load. This is typically less important for bulk cargo.

On the other hand, lake freighters face smaller waves, so they can be made less strong and more streamlined, which is good for fuel efficiency. PiusImpavidus (talk) 10:21, 8 July 2021 (UTC)[reply]

Though not so good for ships like the Edmund Fitzgerald. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:13, 9 July 2021 (UTC)[reply]

Lake freighter design is limited by the ability to get through Poe Lock - 1,200 feet (370 m) long, 110 feet (34 m) wide, and the St. Mary's River at 25.5 ft deep. Smaller ones that travel both the ocean and Great Lakes are limited to Seawaymax based on the locks in the St. Lawrence River. According to our article, ships can be built longer and narrower than ocean-going ship because the Great Lakes waves have a shorter frequency reducing hogging. There is only bulk shipping on the lakes, no container ships so comparing to an ocean-going bulker would be more appropriate. MS Ore Brasil carries 5 times the load of Gott at about the same speed but uses only twice the rated engine power. So 2.5 times the efficiency, perhaps. Rmhermen (talk) 01:05, 12 July 2021 (UTC)[reply]

PiusImpavidus's three bullet points apply to container shipping, not to bulk shipping by self-unloaders as occurs on the Great Lakes. Rmhermen (talk) 01:23, 12 July 2021 (UTC)[reply]

July 10

Why UV rays is good for health if it is higher frequency than 5G?

Ultraviolet rays from the Sun are high-frequency and can be dangerous.

Source

Why UV rays is good for health with such higher frequency? Good means here Rizosome (talk) 15:25, 10 July 2021 (UTC)[reply]

You just quoted something saying it wasn't good for your health. You seem to have answered your own question by showing your question is false. While it is an oversimplification to say that UV is dangerous, you haven't presented anything suggesting it is good for your health. --OuroborosCobra (talk) 15:36, 10 July 2021 (UTC)[reply]

You can also kill yourself by drinking too much water. Is water "bad" for you? You can die from exposure to high heat, doesn't mean that low temperatures are always preferred. You can also freeze to death. Arsenic is a necessary micronutrient, but you shouldn't consume mass quantities. It's ALWAYS about the amount. --Khajidha (talk) 17:58, 10 July 2021 (UTC)[reply]

The health benefits (serotonin release) are only triggered by visible light. This does not include UV radiation, which is electromagnetic radiation outside the visible spectrum (the small portion of the electromagnetic spectrum of light that is visible to the human eye), as shown in this image. --Lambiam 18:50, 10 July 2021 (UTC)[reply]

Vitamin D production uses UV, but very small amounts are sufficient. And, again, higher levels cause deleterious effects.--Khajidha (talk) 19:45, 10 July 2021 (UTC)[reply]

@Rizosome: Did you read through the second link you posted? It clearly explains the benefits and risks of UV exposure. It even goes as far as saying, "According to [the World Health Organization], getting anywhere from 5 to 15 minutes of sunlight on your arms, hands, and face 2-3 times a week is enough to enjoy the vitamin D-boosting benefits of the sun. Note that the sun must penetrate the skin. Wearing sunscreen or clothing over your skin won’t result in vitamin D production. But if you’re going to be outside for more than 15 minutes, it’s a good idea to protect your skin. You can do that by applying sunscreen with a sun protection factor (SPF) of at least 15. Wearing a protective hat and shirt can also help." What has 5G got to do with anything? What are you actually asking? nagualdesign 20:09, 10 July 2021 (UTC)[reply]

I included 5G because my question based on frequencies which are exposed to humans. Rizosome (talk) 07:20, 11 July 2021 (UTC)[reply]

All electromagnetic radiation has frequencies. That is a basic property of light/EM radiation. --OuroborosCobra (talk) 14:40, 12 July 2021 (UTC)[reply]

Your title has a link to 5G. I assume you did not intend that. Ultraviolet has an upper frequency of around 750 THz? Martinevans123 (talk) 14:49, 12 July 2021 (UTC)[reply]

July 11

Mild climate areas

Is there anywhere on earth (on land, mid-ocean would be uninhabitable) where the temperature only rarely, if ever, goes below 0°C or above 30°C? Roger (Dodger67) (talk) 07:33, 11 July 2021 (UTC)[reply]

San-Francisco? Though sometimes it is above 30. Ruslik_Zero 08:28, 11 July 2021 (UTC)[reply]

Auckland, and much of the North Island of New Zealand.-gadfium 08:59, 11 July 2021 (UTC)[reply]

Guernsey? Santa Cruz das Flores? You can try any small island at temperate to subtropical latitudes. PiusImpavidus (talk) 09:39, 11 July 2021 (UTC)[reply]

Isles of Scilly has a record high of 27.8°C and a record low of -7.2.

Jamestown, Saint Helena has a record high of 33.9°C and a record low of 14.4.

Tristan da Cunha has a record high of 24.4°C and a record low of 4.6°C, but it rains for 252 days of the year.

Alansplodge (talk) 11:13, 11 July 2021 (UTC)[reply]

The climate of all of Cornwall is very similar to that of the Scilly Isles. --Lambiam 20:23, 11 July 2021 (UTC)[reply]

Quito#Climate. Average high is about 21 degrees Celsius every month of the year, and average low is about 10 degrees every month of the year. The record low for any month is 2.2 degrees, and only 4 months have ever recorded above 30. 72.77.42.118 (talk) 12:57, 11 July 2021 (UTC)[reply]

July 12

Exposed to rabid bat

200 people exposed to rabid bat at zoo and will get vaccinations. Is being "exposed" to a rabid bat dangerous, if it doesn't actually bite you? Like can it shoot rabies beams out of its eyes if it stares at you, or anything like that? I was nowhere near this incident but it wouldn't have occurred to me to seek emergency vaccination just because I was near a rabid bat, without being in actual contact. Wondering if I'm being cavalier. I looked at wp's rabies article and the parts about transmission didn't make it sound like non-contact infection was really a thing, and if I was bitten at night I like to hope I'd know it. Otherwise it seems unsafe to camp anywhere there might be bats, which is almost everywhere. But maybe I missed something. Thanks. 2602:24A:DE47:BA60:8FCB:EA4E:7FBD:4814 (talk) 00:22, 12 July 2021 (UTC)[reply]

This is probably a case of the authorities (and the the facility, with its resulting liabilities here) embracing the precautionary principle, since the difference between prophylactic and post-symptomatic action can render to rather dramatic differences in probable outcomes when it comes to treatment for rabies. It is possible, though uncommon, for rabies to be transmitted without a bite, notably where infected saliva makes contact even with a very slight scratch or ulceration, or with the mucosa of the oral, nasal, or ocular cavities. Additionally, many bat species are diminutive enough in size that a bite may not be in all instances apparent from tactile/nociceptive sensation or even visual examination. The linked story leaves open rather a lot of questions about the context of the facility and circumstances in which these visitors were overnighting, but given the apparently enclosed environs which these people shared with the bats, I am not surprised health officials felt vaccination was advisable. Here is a delphi method study which investigates when post-exposure vaccination is most particularly warranted: the study does emphasize a rather high level of caution with regard to bats, even when the type of exposure is unknown. Snow ^{let's rap} 00:48, 12 July 2021 (UTC)[reply]

Our article at Rabies transmission says that "Transmission may rarely occur via an aerosol through mucous membranes; and might conceivably endanger people exploring caves populated by rabid bats. However, aerosol transmission of rabies has not yet been well documented in the natural environment." and both halves are referenced. So, why err on the side of caution? Because active rabies is a death sentence. The treatment is not anywhere near as bad as what it used to be like, so there's really no need to take the risk, even if it's a small one. Matt Deres (talk) 13:58, 12 July 2021 (UTC)[reply]

Because active rabies is a death sentence. Just to emphasize this: there have been a total of 11 recorded people who have survived rabies without the vaccine throughout human history, all of whom received a a somewhat controversial treatment since 2003 (with 10 of them occurring since 2014). For context, about 59,000 people die of rabies worldwide each year. If we just look at the disease since the advent of that treatment, then that's a survival rate of 0.001097% (just slightly over 1/1000ths of a percent), a survival rate which is only achieved through the use of a therapy which requires a 17-page guide with 22 steps for the physician to implement, and which requires the presence of significant medical resources (something to which most victims have no access). Also note that the therapy had been attempted 41 times, meaning it's effectiveness stands at about 27%. So even with therapy, most patients die.

The morbidity of untreated rabies is 100%. This warrants the taking of extreme precautions, even when the risk of actual infection is low. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 14:30, 12 July 2021 (UTC)[reply]

Flake of lead paint in the human body

The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

If a child, or anyone, ingests flakes of lead paint, what exactly happens to the flake? I’m sure stomach acid causes lead to be released from the flake, but is the flake physically destroyed, and/or is it invariably flushed out of the body? One thing I’m worried/wondering about is if the flake could adhere to the wall of the small intestine, releasing lead over a longer period of time.Rich (talk) 01:01, 12 July 2021 (UTC)[reply]

Unfortunately, this question runs up against the prohibition against offering medical advice, particularly insofar as you seem to have a personal concern about it. I will go as far as to say that in cases of ingestion, acute lead poisoning can have significant effects even if a solid mass of the type you speculate about passed completely through the GI tract. Obviously the amount of exposure here is of great significance, but one thing we absolutely cannot speculate about here is whether or not the amount likely to be present in a paint chip is likely to be of idiopathic concern to a particular person. If you or someone you know has consumed lead-based paint, it is best to present these questions, along with more particularized details, to a licensed physician/health care provider, or at least the poison control hotline in your locality. Snow ^{let's rap} 01:16, 12 July 2021 (UTC)[reply]

Richard L. Peterson, please read Lead poisoning and Lead paint and Blood lead level and Chelation therapy, and read the references too. If your interest is theoretical, you will learn a lot. If your interest is practical, please have the exposed person seek competent medical attention immediately. Cullen³²⁸ Let's discuss it 01:30, 12 July 2021 (UTC)[reply]

why are you so obnoxiously trying to seize the high ground? Stop this implication that I should have known to read chelation article before asking a question here.(if indeed the chelation article discusses adherence of paint flakes to the intestinal wall, as you imply, since you want me to read it. Since my interest is not what you have decided to call “practical”, there wasn’t a reason for me to look at the chelation article.Rich (talk) 01:42, 12 July 2021 (UTC)[reply]

Rich, I really don't think that response is appropriate or helpful here. Cullen was clearly making a good faith attempt to connect you with the information you sought while also adding a note of caution out of presumably real concern for you or a loved one if your interest related to anything more than the abstract--which was not at all an unrealistic concern given your original post included an implication that you were "concerned" regarding the prospect of lead being retained in the GI tract. Beyond that, I don't see anything in Cullen's response which suggests that he is some way trying to high road you here: even re-reading his comments, I struggle to understand what you even mean by that in this context. Given your ambivalent response and the proscription against providing medical advice here, I was tempted to just blank this entire thread after your second post. But I'm going to take the approach of hatting the discussion instead, with a request to my fellow ref deskers not to reverse this, since I don't think engaging with you on this topic is prudent, since it involves rather complicated pathophysiology and I have concerns about how you will assimilate the kind of gung-ho speculation such questions sometimes receive here. If your interest really is purely abstract then there are forums where you will find no shortage of people willing to give you their two cents, but I urge you should be careful what you internalize from any feedback you receive in open forums online.Snow ^{let's rap} 02:00, 12 July 2021 (UTC)[reply]

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Categorizing colors as having properties analogous to phonemes and music

I wish I could explain this, but:

The colors red, yellow, and green have an appearance that is analogous to the sounds of B, D, and G and legato music.

The colors cyan, blue, and magenta have an appearance that is analogous to the sounds of P, T, and K and staccato music.

Any better description each of the above groups of 3 colors I mentioned?? Warm and cool is not a good choice because green is cool and yet it is categorized with red and yellow here. (Interestingly enough, both black and white are in the category I put cyan, blue, and magenta in; even though they are complete opposites.) Georgia guy (talk) 01:33, 12 July 2021 (UTC)[reply]

You will probably be interested in our article synesthesia (though if you know the meaning of term phonemes, I would expect you are at least vaguely aware of this perceptual phenomena). In short, you may have a particularly noticeable association between visual and auditory qualia in these categories, a phenomena which is by no means uncommon, but particularly pronounced for some individuals. However, it is probable, insofar as our yet-cloudy understanding of the neurology involved here suggests, that these associations are somewhat more idiosyncratic to you, rather than being products of any shared physical qualities arising from the physical laws with give rise to these disparate sensory stimuli--see also our ideasthesia article in this respect.

At least, I believe I am answering your question head on: I admit your wording is a little confusing to me and I am not 100% certain that you are talking about something you perceive in the sensory sense, so much as some abstract mathematical/morphological feature of these phenomena which you believe you have observed them to share in common. Snow ^{let's rap} 01:47, 12 July 2021 (UTC)[reply]

It sounds like you're associating colors whose spectrum contains blue (see Primary_color#Additive_mixing_of_light) with aspirated consonants or unvoiced consonants and staccato notes. Do the P sounds in "spin" and "pin" match up with the same colors in your perception? --Amble (talk) 16:34, 12 July 2021 (UTC)[reply]

Your two color sets are also very similar to Palette 0 and Palette 1 of the 320x200 graphics mode of a CGA monitor; see Color_Graphics_Adapter#320x200. If you have spent a lot of time playing computer games on a CGA monitor, that could be a reason why those two sets of colors are strongly associated in your mind. --Amble (talk) 16:45, 12 July 2021 (UTC)[reply]

I'm talking about voiced/voiceless sounds; to me aspiration isn't important because anglophones don't recognize aspiration as an important property of phonemes. Distinguish the sounds in "spin" and "bin". Georgia guy (talk) 17:37, 12 July 2021 (UTC)[reply]

It's not necessarily true in English that voicing is important and aspiration isn't important. See for example [2]. The question is: does "spin" line up for you with red-yellow-green or with cyan-blue-magenta? What about "metal", "mettle", "medal", "meddle"? --Amble (talk) 18:04, 12 July 2021 (UTC)[reply]

All voiceless consonants like up with cyan-blue-magenta. Georgia guy (talk) 19:03, 12 July 2021 (UTC)[reply]

In American English, "metal", "mettle", "medal", and "meddle" are ordinarily pronounced identically (flapping). So I'm curious whether these are all red-yellow-green for you (because they are realized as voiced), or the ones written with T are cyan-blue-magenta (following the spelling). --Amble (talk) 19:16, 12 July 2021 (UTC)[reply]

This is about the phonemes themselves regardless of their context. If the phoneme depends on the dialect, then so does what it lines up with. Georgia guy (talk) 19:23, 12 July 2021 (UTC)[reply]

Featured picture

Is the crested shriketit considered a beneficial species or a harmful one? Because if you look at its feeding behavior, it's easy to see how it could go either way! 2601:646:8A01:B180:4CF:59F2:CEF2:C1A6 (talk) 02:18, 12 July 2021 (UTC)[reply]

A cursory search does not turn up anything suggesting that this species is considered a pest or anything other than an organism living in its ecological niche. In fact, some of the little information I could turn up regarding its distribution and status suggest that its numbers are somewhat under pressure from habitat loss. I presume that the detail of their feeding habits that makes you contemplate this question is the fact that they strip bark from trees? This isn't a super unheard of trait amongst avian foragers and does not in and of itself indicate an especially parasitic relationship with the trees in question. These behaviours often become problematic in the context where a given organism is an invasive species to a new region that has not evolved in lockstep with it, affording the plants in question time to evolve defense against it (or even a mutualistic relationship) whereas here--though I am somewhat venturing out into speculative territory now--since that is not the case in this instance, it is probable an ecological balance has been established in regard to this behaviour--after-all, in the longhaul any adaptive behaviour which too negatively impacts a species which the bird in question is dependent on as a host to its calories, will be selected against. That's not to say there are not exceptions to that rule, but bark stripping is, again, not a super uncommon feature among both birds and mammals which predate insects.

Of course, in any event, "beneficial" vs. "harmful" species is a highly speculative distinction which may be based on more than ecological concerns, but in any event, I am not seeing anything indicating high levels of frustration with this species in any context, so my best-guess response here is that these birds are generally regarded as beneficial, at least to the extent that any species just going about it's business expressing its behaviours in the ecosystem is generally considered beneficial. Please take all of that with the note of caution that I cannot provide a source for you which itself directly addresses your inquiry, however. Snow ^{let's rap} 03:03, 12 July 2021 (UTC)[reply]

How scientists prepared vaccines against new disease COVID but not old deadly disease HIV?

I always wonder how scientists develop vaccine for novel coronavirus faster than HIV virus which pandemic started around 1980s.

Is this because of corona being short term disease? There is no vaccine for HIV currently source, but recently its vaccine trails begin at Oxford source Rizosome (talk) 19:54, 12 July 2021 (UTC)[reply]

HIV attacks the immune system in particular, unlike COVID-19. If the immune system is targeted, probably it's a lot harder to create a vaccine. 74.98.192.38 (talk) 20:07, 12 July 2021 (UTC)[reply]

Direction of floating in outer space

If Earth's graviational influence extends into outer space and on the Moon in particular, does it mean that any foreign artificial object (or the dead astronaut's body) floating/drifting in the vicinity, would eventually be pulled towards Earth or some other astronomical object for that matter? More generally, would that artificial object or astronaut drifting in the interstellar medium be eventually captured by some gravitational field? 212.180.235.46 (talk) 20:02, 12 July 2021 (UTC)[reply]