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Why Do People In Old Movies Talk Weird?
 
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It’s not quite British, and it’s not quite American – so what gives? Why do all those actors of yesteryear have such a distinct and strange accent? Learn more at HowStuffWorks.com: http://entertainment.howstuffworks.com/movies-film-channel.htm Share on Facebook: http://goo.gl/1j6yim Share on Twitter: http://goo.gl/4FoAQy Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com If you’ve ever heard old movies or newsreels from the thirties or forties, then you’ve probably heard that weird old-timey voice. It sounds a little like a blend between American English and a form of British English. So what is this cadence, exactly? This type of pronunciation is called the Transatlantic, or Mid-Atlantic, accent. And it isn’t like most other accents – instead of naturally evolving, the Transatlantic accent was acquired. This means that people in the United States were taught to speak in this voice. Historically Transatlantic speech was the hallmark of aristocratic America and theatre. In upper-class boarding schools across New England, students learned the Transatlantic accent as an international norm for communication, similar to the way posh British society used Received Pronunciation – essentially, the way the Queen and aristocrats are taught to speak. It has several quasi-British elements, such a lack of rhoticity. This means that Mid-Atlantic speakers dropped their “r’s” at the end of words like “winner” or “clear”. They’ll also use softer, British vowels – “dahnce” instead of “dance”, for instance. Another thing that stands out is the emphasis on clipped, sharp t’s. In American English we often pronounce the “t” in words like “writer” and “water” as d’s. Transatlantic speakers will hit that T like it stole something. “Writer.” “Water.” But, again, this speech pattern isn’t completely British, nor completely American. Instead, it’s a form of English that’s hard to place… and that’s part of why Hollywood loved it. There’s also a theory that technological constraints helped Mid-Atlantic’s popularity. According to Professor Jay O’Berski, this nasally, clipped pronunciation is a vestige from the early days of radio. Receivers had very little bass technology at the time, and it was very difficult – if not impossible – to hear bass tones on your home device. Now we live in an age where bass technology is booms from the trunks of cars across America. So what happened to this accent? Linguist William Labov notes that Mid-Atlantic speech fell out of favor after World War II, as fewer teachers continued teaching the pronunciation to their students. That’s one of the reasons this speech sounds so ‘old-timey’ to us today: when people learn it, they’re usually learning it for acting purposes, rather than for everyday use. However, we can still hear the effects of Mid-Atlantic speech in recordings of everyone from Katherine Hepburn to Franklin D. Roosevelt and, of course, countless films, newsreels and radio shows from the 30s and 40s. SOURCES: http://www.motherjones.com/kevin-drum/2011/08/oh-old-timey-movie-voice http://news.discovery.com/history/us-history/old-time-baseball-players-talk-130404.htm http://web.archive.org/web/20051118050043/http://www.ling.upenn.edu/phonoatlas/Atlas_chapters/Ch7/Ch7.html http://www.slate.com/articles/news_and_politics/explainer/2008/02/why_did_william_f_buckley_jr_talk_like_that.html
How Does The Common Cold Work?
 
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We've all had a cold at one point or another; it entails an uncomfortable cocktail of symptoms like sneezing, coughing and a runny nose. But why do we get colds? How do they work? Find out in this episode of BrainStuff! Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Why Do Limbs Fall Asleep?
 
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Pressure on nerves can cause the nerves to stop sending impulses to the brain, causing limbs to fall asleep. Learn more about limbs falling asleep in this episode of BrainStuff. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
How Does LASIK Work?
 
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Jonathan Strickland explains the process and risks of LASIK surgery, from preoperative exams, to lasers in your eyes. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Subscribe Now! http://www.youtube.com/subscription_c... Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff For centuries we’ve relied on external lenses (like glasses or contacts) for correction. But with modern technology surgeons can actually alter the shape of the eye itself using lasers to change its focal point. The most popular technique is called LASIK, which stands for Laser-Assisted In-Situ Keratomileusis. It’s very effective at treating several visual problems, especially near-sightedness. Before any reputable eye doctor performs LASIK, they’re going to give you a thorough preoperative eye exam. They’ll measure your current prescription and manually check the surface of your cornea with a dye called Fluoracaine. Other tests map your cornea’s topography and measure the exact diameter of your pupil. To qualify for LASIK, you’ll need to meet a certain range of vision, corneal thickness and pupil size. It’s also risky if you’re pregnant, have severe heart problems, certain diseases, or take some types of drugs. Once you’ve passed pre-op assessment, you come back for the actual LASIK process, conducted by both the surgeon and a technician operating the laser machine. They’ll put a topical anesthetic in your eyes to numb any discomfort. That’s good, because the next step is to pry open your eyes with special tape and that good old Eyelid speculum. Then they’ll calibrate the laser and mark your cornea for alignment. Using a suction ring and an extremely precise surgical blade called a microkeratome, the surgeon cuts a flap in your cornea and folds it back. You’ll be asked to focus on a red light which isn’t the laser, but helps center your eye. Now it’s laser time! An Excimer laser mixing reactive gases like chlorine and fluorine with inert gases like argon, krypton and xenon, produces a tightly focused beam of ultraviolet light that vaporizes a microscopic portion of the cornea. This is a “cool laser” that doesn’t heat the surrounding air or surface. Instead it breaks down the molecular bonds of organic materials. The beam itself is microscopic, less than a nanometer wide. The surgeon reshapes the cornea by controlling the size, position and number of laser pulses applied. Surprisingly, this only takes a few seconds. When it’s finished, your corneal flap is replaced with a small antibiotic added. The cornea heals and rebonds immediately, naturally sealing itself again. Taking into account the time for both eyes, the entire procedure is usually done in only 15-30 minutes. After the operation they’ll give you these cool eye shields that prevent you from touching your eyes but let you see enough to get around. You’ll wear them the rest of the day and sleep in them that night. Of course, someone has to drive you home and once you get there you’ll need to apply rewetting drops, antibiotic drops and possibly a moisturizing gel inside your bottom eyelid. The opthamologist will follow up the next day and on a recurring basis for about a year. Now you’re probably asking, “But Jonathan, couldn’t there be side effects when a doctor shoots a laser into my eye?” Of course there could. Most commonly, eyes can be undercorrected, overcorrected or get a small wrinkle when the corneal flap is replaced that causes a blur. For the most part these are easily fixed with a second procedure. Sometimes a surgeon won’t even recommend further refining since many recipients of LASIK never achieve “normal vision,” but do reduce their corrective prescriptions significantly. Other, rarer side effects can include halos around lights, light sensitivity and double vision. I’d be lying if I said there wasn’t a chance of partial or complete blindness, but it is miniscule compared to the success rate. This is especially true if you’re seeing a reputable doctor. Keep in mind that there are so many unscrupulous practitioners out there that the FDA had to issue a stern warning about dodgy sales pitches underplaying the risks of LASIK. But twenty-five years after it was invented by Gholam Peyman, LASIK is safer than ever before. http://health.howstuffworks.com/medicine/surgeries-procedures/lasik.htm http://podcasts.howstuffworks.com/hsw/podcasts/techstuff/2011-10-24-techstuff-laser-eye-surgery.mp3 YOUR EYES. By: Sklar, Hallie Levine, Health (Time Inc.), 1059938X, Apr2013, Vol. 27, Issue 3 LASIK: Illustration. CRS - Adult Health Advisor, Jun2012
What The Heck Is GDP?
 
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GDP, GNP – what does it all mean? Jonathan explains what economists mean when they bring up these common economic indicators. Learn more at HowStuffWorks.com: http://money.howstuffworks.com/gross-national-happiness.htm Share on Facebook: Share on Twitter: Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com OK, let’s say you’ve just gotten a job offer to work in the majestic country of Bumpsylvania. Awesome, right? You’ve always wanted to live amongst the scenic Bumpsylvanian swamplands and hear the local ghost toads sing their famous mating screech. But before you pony up the $549.95 for Rosetta Stone: Bumpsylvanian Edition, you want to do a little research on the economic health of this country. So you ask your friend the economics professor: How is the economy of Bumpsylvania doing these days? One number that will almost definitely figure into her reply is the country’s GDP. This stands for Gross Domestic Product. GDP is a common measure that’s used to roughly represent the size of a country’s economy. The way you calculate GDP is both simple as a general principle, and complicated in the details. The simple version is that GDP is the value of all the goods and services produced within a country in a given period of time, such as a financial quarter or a year. So if we look at Bumpsylvania, we can calculate its yearly GDP by adding up the dollar-value of all the stuff it creates: All the pork sandwiches, shoe shines, fashion magazines, bullets, massages, motorcycles, jiu-jitsu classes, ghost toad swamp tours, and, of course, traditional, Bumpsylvanian-style wooden hats. Every item, product or service brought to market by workers or other economic resources located inside the country in that year is part of the GDP. Coming up with this figure is not as easy as it sounds. GDP is actually a highly complex and abstract statistical instrument that takes some real work to calculate. Just one example of the many complications: Let’s say somebody cuts down some swamp trees and turns those trees into lumber, and then sells that lumber to a haberdasher who turns it into a traditional, Bumpsylvanian-style wooden hat. Do you count the sales of both the lumber _and_ the hat? Well, no, because GDP is a measure of the final value of goods and services. So if you counted the sale of the wood to the hat-maker and the sale of the hat, you’d be counting the same value twice. The value of the wood gets wrapped into the final value of that gorgeous, gorgeous headgear. GDP is probably the most important measure of the size and performance of an economy, but it’s not the only one. There’s also GNP, which is related, but slightly different. GNP stands for gross national product. The difference is that GNP is the value of all the products and services produced by a country’s residents, even if production takes place outside of the country. So if a Bumpsylvanian business has a factory making wooden hats in another country, the output of that factory would be included in Bumpsylvania’s GNP, but not its GDP. While GDP is a widely used indicator of economic strength, many critics point out that it’s not necessarily the best indicator of the “real” health of a nation. For example, a country with a large, growing GDP might look strong on paper, but what if that number is masking vast income inequality – a productive economy based on huge amounts of low-wage labor? Of course by comparing GDP with other pieces of data, you can do more with the figure. A simple example would be comparing GDP with population to come up with Per Capita GDP (which means economic value per person). So for example, according to the World Bank, in 2013, China’s GDP was a massive $9.2 trillion. Compare that to Luxembourg’s relatively small GDP of $60 billion. Yet in the same year, China’s GDP Per Capita was only about $6,800, while Luxembourg’s was more than 16 times that, at about $110,000. So while China’s economy is certainly much larger, it looks like each individual citizen, on average, is better off in Luxembourg. Financially speaking, that is. SOURCES: http://www.britannica.com/EBchecked/topic/246663/gross-national-product-GNP http://www.bea.gov/newsreleases/national/gdp/gdpnewsrelease.htm http://www.britannica.com/EBchecked/topic/246647/gross-domestic-product-GDP http://money.howstuffworks.com/gross-national-happiness.htm/printable http://www.nytimes.com/2013/10/05/world/asia/index-of-happiness-bhutans-new-leader-prefers-more-concrete-goals.html?_r=0 https://books.google.com/books?id=V5IpAgAAQBAJ&printsec=frontcover&dq=how+to+calculate+gnp&hl=en&sa=X&ei=QlVyVZH1CJKFyQTo-4D4CQ&ved=0CDYQ6AEwAg#v=onepage&q=how%20to%20calculate%20gnp&f=false http://data.worldbank.org/indicator/NY.GDP.MKTP.CD http://data.worldbank.org/indicator/NY.GDP.PCAP.CD http://www.factcheck.org/2008/02/gdp-vs-gnp/
What Causes The Northern Lights?
 
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There are many misconceptions about what causes the Aurora Borealis when it really requires solar winds, magnetic fields and excited atmospheric gases. Learn more at HowStuffWorks.com: http://science.howstuffworks.com/nature/climate-weather/atmospheric/question471.htm Share on Facebook: http://goo.gl/FMuiBa Share on Twitter: http://goo.gl/TR4YyU Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com The Northern Lights are beautiful and odd and have understandably inspired many myths. The Vikings thought they were a bridge between our world and Asgard where Thor and the other gods live. In another Norse myth, they are the light reflected of the armor of the Valkyries. And people in Finland thought it was the archangel Michael (John Travolta) battling Beelzebub (the devil). Wrong. Wrong. Wrong. All wrong. It was the famous early astronomer and recanter of science, Galileo Galilei, who gave the Northern lights the name Aurora Borealis, which means “dawn of the North” in Latin. But it wasn’t until Norwegian scientist Christian Birkeland figured it out in 1896 that the true origin of the auroras was understood. In the center of the Earth, the molten iron core generates magnetic fields that extend through the crust and into space around the planet, creating what’s called Earth’s magnetosphere. It’s a pretty great thing that Earth has it, because the magnetosphere protects us from all manner of charged particles spit out from the Sun. The Sun is so hot that it produces plasma (a fourth state of matter) where positively charged atoms (ions) and negatively charge electrons flow freely around one another. These highly charged particles have enough energy to escape the Sun’s gravity and fly out into space, barreling toward Earth at 1 million miles per hour like a shotgun blast of solar hate. This is called solar wind. When they encounter our magnetosphere, most of these ions and electrons bounce harmlessly off and Earth is saved. But some of these particles make it through the magnetosphere where it’s weakest (at the north and south poles), and when they do the light show begins. The electrons that make it into our atmosphere interact with some of the elements there, particularly oxygen and nitrogen. The electrons transfer energy to them, exciting them in the process. To calm down, the excited atoms must release some energy, which they do as tiny packets of light called photons -- beautiful, beautiful photons. Depending on where in the atmosphere the electrons interact with these other atoms, different colors are produced. Oxygen emits a yellow-green color up to about 150 miles in the atmosphere. After that, it turns red. Nitrogen emits a nice blue color about 60 miles up. And don’t forget these colors can blend, which can create glowing pinks, purples and whites. It’s like Miami Beach up there. This interplay is most vibrant during solar storms, which depend somewhat on the Sun’s solar cycle. And, although these lights can be produced at all hours, they aren’t visible during the day, since the sunlight outshines them. SOURCES: http://science.howstuffworks.com/nature/climate-weather/atmospheric/question471.htm http://www.physics.org/article-questions.asp?id=64
What Is White Noise?
 
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Jonathan defines what white noise actually is and how it's used to mask other annoying sounds. Learn more at HowStuffWorks.com: http://science.howstuffworks.com/question47.htm Share on Facebook: http://goo.gl/n7YNrZ Share on Twitter: http://goo.gl/Fq9InS Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Cross over into BrainStuff now children. All are welcome! But… before we go into the light together, there seems to be some confusion among you about what “white noise” is. No, it isn’t when you have that snowy static on your TV and ghosts fly out of the screen and your daughter says, “They’re here!” White noise is something we’ve all heard, some of us without even knowing it. So let’s define what it is exactly, how it’s used to mask other sounds and what other “colors” exist on the spectrum of sound. The simplest definition is that white noise is the noise produced by combining all the different frequencies of sound together at once. Each of these frequencies is projected at an equal amount, from low to high. Because white noise has an equal energy distribution, sound technicians refer to its frequency spectrum as being completely flat. Some machines -- like fans for instance -- can create an approximation of white noise by hitting all these notes. That’s why they’re so good at creating background noise that masks other sounds. When there are sudden changes in noise, we’re often distracted by the jarring clash. Especially if we’re sleeping. White noise’s masking effect blocks out those changes, making it easier to sleep through the night. That’s one reason some people leave a fan, air purifier or a television on in the middle of the night. This sound masking is also used to block noise in places like offices, hotels and libraries, often broadcast over a PA system. If you’re trying to concentrate in a disturbing environment and there aren’t filters like these in place, you can always listen to white noise on your headphones to mediate the conflicting sounds around you. How do you think we write these BrainStuff episodes when we all live together in this tiny studio prison and are never allowed to leave? There is peace and serenity in the white noise. We call it “white” noise because it’s analogous to how white light works, being made up of all the different frequencies of light. But white noise isn’t the only “color” on the sound spectrum. Depending on the way signals are distributed over different frequencies they can be red, blue, violet or gray. Pink noise for example is very similar to white noise, but its higher frequencies have less intensity, making it louder and more powerful on the low end. This makes it useful for testing speakers and amplifiers. Like white noise, it’s also used to mask background sounds. And pink noise even occurs naturally in heartbeat rhythms, meteorological data and the radiation output of astronomical bodies. SOURCES: http://science.howstuffworks.com/question47.htm http://www.popsci.com/article/science/fyi-why-does-white-noise-help-people-sleep Spinney, L. (2008). The noise within. New Scientist, 198(2661), 42-45 Carroll, J. (2012). Can white noise ease tinnitus effects?. Plant Engineering, 66(8), 19. http://www.wired.co.uk/news/archive/2011-04/7/colours-of-noise http://www.livescience.com/38464-what-is-pink-noise.html
How (And Why) Do Cats Purr?
 
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Cats purr for all kinds of reasons, including communication and healing themselves. Cristen explains how purring works and which cats can't do it. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Download the New TestTube iOS app! http://testu.be/1ndmmMq Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
How Do One-Way Mirrors Work?
 
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How can a single piece of glass look like a mirror from one side but a window from the other? It's not magic, it's materials technology. Learn more at HowStuffWorks.com: http://science.howstuffworks.com/question421.htm Share on Facebook: http://goo.gl/b6Tts3 Share on Twitter: http://goo.gl/mQM4qB Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Hi! I’m Jonathan, this is BrainStuff, and today we’re talking one-way mirrors, aka two-way mirrors, aka half-silvered mirrors, aka transparent mirrors, aka security mirrors, aka surveillance mirrors, aka observer-ator-trons. Y’know, those things you see in crime dramas when one cop’s interrogating a suspect, while another watches through a window that appears - from the suspect’s side - to be a mirror. It’s not magic. TV cops aren’t wizards. Except sometimes they are. But that’s fiction, and transparent mirrors are science. Specifically, materials science and optics. OK. A regular ol’ mirror – the kind hanging over your bathroom sink – is a sheet of glass holding up an extremely thin layer of reflective metal. The metal comes in the form of a metallic salt, which can be dissolved in liquid and sprayed onto the glass in a process called silvering. That’s because silver nitrate was the first stuff used for this process. These days, most mirrors are actually silvered with aluminum, which is cheaper and sturdier. But silvering doesn’t make perfect mirrors: They reflect most light, but a little is still transmitted through infinitesimal gaps in the reflective metal layer. So everyday mirrors receive an opaque backing, like dark paint. This stops cold any photons that slip through the metal layer (and protects it from scratches). Without the backing, you’d be able to faintly see the wall behind the mirror. But what if you purposefully make a mirror imperfect? Manufacturers of transparent mirrors spray an even thinner, less dense layer of silvering onto the glass. Meaning it reflects less light – for example, let’s say half the light of an ordinary mirror. The rest passes straight through the glass like it’s a window. Which it is. A transparent mirror, with its sparse silvering and lack of backing, is just a reflective window. And it’s a window from both sides! So: How come the suspect sees his reflection, but the cop sees the suspect? It’s a trick of the light. The observer room is kept dark, while the observee’s room is lit up like the Vegas strip. So on the cop’s side, more light is coming through the glass than being reflected from the room. And from the suspect’s side, more light is reflecting from the room than being transmitted through the glass. And hey, people ask about this a lot: If you ever want to test a mirror to see if it’s transparent, block the light around you and try to peer through. A bright flashlight can help illuminate anything that might be behind the mirror. CREDITS: "Bean" movie clip from MovieClips.com YouTube channel: https://www.youtube.com/watch?v=fkHlhiG0h70 SOURCES: http://science.howstuffworks.com/question421.htm/printable http://science.howstuffworks.com/innovation/everyday-innovations/mirror.htm/printable http://articles.adsabs.harvard.edu//full/1911PASP...23...13C/0000015.000.html http://www.google.com/patents/US2996406 http://www.photonics.com/EDU/Handbook.aspx?AID=25501
Why Do So Many Price Tags End In .99?
 
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It’s very common to see the number 9 at the right end of a price tag. Why is this? Lauren explains the psychology of prices and nines in this episode of BrainStuff. Learn more at HowStuffWorks.com. Share on Facebook: Share on Twitter: Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Hi there! I’m Lauren, and this is BrainStuff. The other day I was shopping at Bavmorda’s Trebuchet and Millinery Emporium and I started wondering -- why do so many prices end in the number 9? You might have wondered the same thing too, and if you have, it’s not just your imagination. Studies have shown that many retailers disproportionately use prices within 5 cents of the nearest dollar, 1 cent of the nearest 10 cents, $5 of the nearest $100 or $1000, and within $1 of the nearest 10-dollar amount. Prices like this are often known as “charm” prices, “odd” prices, “magic” prices, or “psychological pricing.” Pricetags ending in the number 9 are especially common. But why? These days, two main psychological theories of charm pricing have emerged. And yes, this is a field of study. For the purpose of this video, we’ll call them the “rounding off” theory and the “bargain signaling” theory. The rounding off theory argues that shoppers tend to pay a lot more attention to the first digits in a listed price. So, when you see a product labels $29.99, even though it's only 1 penny off from being 30 bucks, the theory goes that you mentally round down to think of it as a $20 price point based on that first digit. For example, a 2005 study found that prices ending in 99 cents caused shoppers to make math errors that even-dollar prices did not. It worked like this: Test shoppers were given an allowance of exactly 73 bucks, and they were then asked to estimate how many products they could buy with this allowance. It turned out that when 99-cent endings were in the picture, shoppers overestimated their spending power. In other words, they thought they could buy significantly more products at prices like $2.99 and $5.99 than they could at $3 and $6. This seems to suggest that we do tend to “round down” and ignore the final digits in prices, even though it makes no economic sense to do so. The bargain signaling theory suggests that odd prices work the same way “Sale” signs do, meaning they imply to shoppers that the price listed is especially good. Maybe the weird specificity of something priced $5.98 or $2.39 makes us think that the store is selling that bag of Gummy Bears at the lowest price point they can possibly afford. Or maybe we’ve all been conditioned by marketing to associate odd prices, especially the ones ending in 9, with sales and discounts. In 2003, researchers showed that in some cases, you could actually increase demand for an item by raising the price so that it ended in a ‘9,’ which would seem to contradict rational economics. One example they studied: A $34 dress in a clothing catalog. By raising the price from 34 bucks to 39 bucks, demand for the dress actually went up. When they raised the price to $44, however, the trend didn’t hold -- so it wasn’t just that buyers liked paying more for their clothes. Since 34 and 39 both start with the same digit, this would seem to favor the bargain signaling theory rather than the rounding off theory. Something about the 9 just seemed to make people think they were getting a good deal. So it looks like our penchant for buying at the 9s might be explained by a mixture of our tendency to round down to the leftmost digit AND our beliefs that 9s inherently indicate bargains. SOURCES: http://www.jstor.org/stable/10.1086/678484?seq=1#page_scan_tab_contents http://www.theatlantic.com/business/archive/2015/01/the-psychological-difference-between-1200-and-1167/384993/ http://timharford.com/2012/06/pound-for-pound-99p-is-worth-every-penny/ http://www.nytimes.com/2009/02/08/weekinreview/08arango.html?_r=0 http://dept.camden.rutgers.edu/business/files/Schindler-2006.pdf http://dept.camden.rutgers.edu/business/files/Bizer-Schindler-2005.pdf http://onlinelibrary.wiley.com/doi/10.1002/mar.20084/abstract https://hbr.org/2003/09/mind-your-pricing-cues http://classes.bus.oregonstate.edu/fall-05/ba499/elton/Articles/Mind%20Your%20Pricing%20Cues.pdf http://link.springer.com/article/10.1023%2FA%3A1023581927405 http://www.ozshy.50webs.com/21why99.pdf https://www_nelsonpricing_com_ar.1.com.ar/biblioteca_pricing/1997-02_why_are_so_many_goods_priced_to_end_in_nine_Basu_K.pdf http://marketing-bulletin.massey.ac.nz/V8/MB_V8_N1_Holdershaw.pdf
What Happens When I Have A Hangover?
 
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If you've ever had a few too many beers at a party, then you've probably encountered the symptoms of a hangover -- the pulsing headache, dry mouth, nausea and more. But what's actually happening to you? And what is it about alcohol that can turn a wonderful Saturday night into an agonizing Sunday morning? Learn more with Ben Bowlin. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. SOURCES Perry, Lacy. “How Hangovers Work.” http://science.howstuffworks.com/life/human-biology/hangover.htm/printable Stuff You Should Know: “What is a hangover, really?” http://www.stuffyoushouldknow.com/podcasts/what-is-a-hangover-really/ “Your Complete Guide to the Science of Hangovers” Stromberg, Joseph. http://www.smithsonianmag.com/science-nature/your-complete-guide-to-the-science-of-hangovers-180948074/?no-ist Download the New TestTube iOS app! http://testu.be/1ndmmMq Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
How quickly does hair grow?
 
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On average, human hair grows a small amount each day. Watch as Jonathan and Lauren explain hair growth in this episode of BrainStuff. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Why Does Hydrogen Peroxide Foam When Put On A Cut?
 
01:55
Hydrogen peroxide's foaming action is due to the catalase in blood and cells. Check out this episode of BrainStuff to learn how hydrogen peroxide interacts with catalase. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
How Can There Be Seedless Grapes?
 
02:09
Seedless grapes are the most common kind on the market, but have you ever wondered how a grape can be seedless? How does it grow? Discover how seedless grapes accidentally came about -- and how they grow -- in this episode of BrainStuff. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Why Shouldn't You Give Honey To Babies?
 
02:54
Botulism bacteria creates a type of poisoning and paralysis -- but how does it actually work? Check out this episode of BrainStuff to learn more about the effects and spread of botulism. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_c... Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff Hi. I’m Lauren, this is BrainStuff, and today’s question is “Why shouldn’t you give honey to babies?” It’s not because bees and babies have an ancient grudge match – probably. It’s because of botulism. Botulism is a condition – a poisoning by the neurotoxin botulinum. It’s named after these bacteria, Clostridium botulinum, that produce the toxin just as a byproduct of existing. In the human body, the toxin attaches to nerve endings that stimulate muscles and block them, preventing them from doing their jobs. This leads to a feeling of weakness, and in severe cases can cause immobilization and even death -- from respiratory paralysis. It’s a less cartoony version of the Joker’s laughing toxin. These bacteria are pretty common, but lucky for us, they’re killed by oxygen – and, as I’ve mentioned before, there’s a good amount of free-range oxygen in our air. Unfortunately, they’ve adapted to form spores around themselves that let them lie dormant until they find themselves back in an oxygen-free environment. When adults get botulism, it’s usually from improperly canned food. During the canning process, if the food is heated properly, it’ll destroy the spores. But if it’s heated improperly, the bacteria can activate once the can’s been sealed, creating that oxygen-free environment they grow in. And that’s why you shouldn’t eat food from bloated cans – the bloat comes from rapid bacterial growth that creates a lot of toxin in the food. Side note: Dented cans are fine. But, OK, we all know that babies are completely incompetent at operating can openers. The thing is, honey frequently contains a few spores of clostridia botulinum – bees accidentally pick them up while they’re collecting nectar. Adults with functioning immune systems and established intestinal flora – that’s the helpful gut bacteria -- can handle a couple spores. But babies can’t. So when the botulinum get into the oxygen-free intestines of the baby, they can activate and poison the baby. This is all scary. Botulinum is one of the most toxic compounds known to humankind. It can be deadly in the magnitude of nanograms. That’s a billionth of a gram. That’s really small. But it can also be used as a medical treatment. When it’s really diluted, doctors can inject it in patients who have overactive muscle conditions that affect their mobility or eyesight. And hey, you’ve heard of Botox? That’s carefully controlled botulism in your face. http://textbookofbacteriology.net/themicrobialworld/Botulism.html http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-safety-fact-sheets/safe-food-handling/shelf-stable-food-safety/ct_index/!ut/p/a1/jVJtT4MwGPw19BtrGdOgSWMQXebUzWXRMb4spZSXhVFsy1B_vS2auE2nQkjbu3t42rvCCIYwqsi2yIgqeEVKs45OV2iGTp2zAI2nZ84Q3UyeZtPbIEDe_EQLlr8IJu4_6488PvqrfvyPBn1xH9xnMKqJyu2iSjkMM6ZsUsmWCQnDlPPEliRl6tVOCVW2zBlTmjCY3bE5qZKyqDKN5axMbalIXH5yH5UwpGpVVAl7gQsY7e8KOfq9mbjzwWg8cdF0cCj4wbYPwXFf9MGzksddRku_il1Pn1CwlAkmeo3QcK5UfW4hC7Vt28s4z0rWo3xjIc1eSIIVEFThNXjGgElBsQSSN4Iy3LIY0AT3ASUJFmsCGm0K9sCWJRgFV9ez4dq_BPov2LSwHNe3nP7QfKZTKgvZa2RCdM9tB9bSDDUXipRmZhRmVLwuaDfbTYAlDe2unyF2cjrU7SRlqO9ZdehXWj_5lHOpYLjvD6w3j-HbnT9CxcNm4Un_HaFCwfA!/#10 http://www.babycenter.com/408_when-can-my-baby-eat-honey_1368490.bc http://www.infantbotulism.org/general/faq.php http://money.howstuffworks.com/personal-finance/budgeting/safe-to-buy-dented-foods-from-grocery-store.htm/printable
Can Absinthe Make You Hallucinate?
 
03:42
Absinthe has a dangerous reputation. But will you really meet The Green Fairy if you drink it? Share on Facebook: http://goo.gl/MxJWVf Share on Twitter: http://goo.gl/wIatnN Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com CREDITS: Anti-Absinthe posters: http://web.cortland.edu/flteach/wksp/French_alcool/ SOURCES: Sayre, C. (2007). Absinthe Is Back. Time International (Atlantic Edition), 170(23), 36. THE LAST WORD. (2013). New Scientist, 219(2928), 149. Padosch, S. A., Lachenmeier, D. W., & Kröner, L. U. (2006). Absinthism: a fictitious 19th century syndrome with present impact. Substance Abuse Treatment, Prevention & Policy, 114. doi:10.1186/1747-597X-1-14 It Makes The Heart Grow Fonder. By: Arnold, Eric, Forbes, 00156914, 9/21/2009, Vol. 184, Issue 5 The Search for Real Absinthe. By: Sullum, Jacob, Reason, 00486906, Aug/Sep2005, Vol. 37, Issue 4 http://science.howstuffworks.com/innovation/edible-innovations/absinthe.htm
How Does Silica Gel Work?
 
02:52
What is silica gel, and why do I find little packets of it in everything I buy? Lauren explains it all in this week's episode. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Download the New TestTube iOS app! http://testu.be/1ndmmMq Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Why Can't We Breathe Underwater?
 
03:22
Water is made up of hydrogen and oxygen, so why aren't we able to breathe underwater? Find out in this episode of BrainStuff. Source: http://science.howstuffworks.com/question386.htm
How Do Accents Work?
 
05:48
Have you ever wondered how accents work? Tune in to this episode of BrainStuff to find out about the ever-evolving accent. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Are Plants Conscious?
 
03:58
Scientists have found evidence that plants have senses, memories, and can even communicate with each other. But does this mean they're conscious? Learn more at HowStuffWorks.com: http://science.howstuffworks.com/life/botany/plants-feel-pain.htm Share on Facebook: https://goo.gl/JEor1U Share on Twitter: https://goo.gl/xM6eZ7 Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com SOURCES: http://science.howstuffworks.com/life/botany/plants-feel-pain.htm http://www.scientificamerican.com/article/do-plants-think-daniel-chamovitz/ https://www.youtube.com/watch?v=fGLABm7jJ-Y http://www.npr.org/blogs/krulwich/2014/04/29/307981803/plants-talk-plants-listen-here-s-how http://gizmodo.com/nice-try-vegans-plants-can-actually-hear-themselves-b-1599749162 Roots of consciousness. By: Ananthaswamy, Anil, New Scientist, 02624079, 12/6/2014, Vol. 224, Issue 2998 Do Plants Have Brains? By: DeSalle, Rob, Tattersall, Ian, Natural History, 00280712, May2012, Vol. 120, Issue 5 http://www.newyorker.com/magazine/2013/12/23/the-intelligent-plant
How Does Sleepwalking Work?
 
04:21
Have you ever walked in your sleep? Somnambulism isn't as rare as you might think. Join Cristen as she explores the facts and fiction about sleepwalking, from its many possible causes to whether you can safely wake up a somnambulist mid-stroll.
How Does A Gas Nozzle Know When To Shut Off?
 
02:43
If you've ever put gas in a car, you've probably noticed how the gas pump shuts off when your tank is full. But how does it know to do that? Learn more about the clever mechanism that keeps your gas tank from overflowing in this episode of BrainStuff. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
How Does Bread Rise?
 
02:09
Lauren explores what's actually happening when we make bread. Hint: It involves plenty of yeast, trapping carbon dioxide and linking gluten molecules. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Download the New TestTube iOS app! http://testu.be/1ndmmMq Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
What Is Synesthesia?
 
04:12
It’s true – some people hear colors, or taste words. But what produces synesthesia? Learn more at HowStuffWorks.com: http://science.howstuffworks.com/life/inside-the-mind/emotions/synesthesia.htm Share on Facebook: https://goo.gl/jowIii Share on Twitter: https://goo.gl/is4WqA Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Have you ever heard a color or smelled a sound? If so, don’t worry: you’re not alone. Instead, you’re part of a group I consider superpowered- you have synesthesia. Or you’ve done some crazy drugs. Maybe that’s a different episode? Anyway, when people with synesthesia experience input from one sense, it results in the experience of another sense. So, if you’re a synesthete like author Vladimir Nabokov, you would associate letters with colors – grapheme-color synesthesia. And there are different types of synesthesia. Nabokov called his “color hearing”. This grapheme-color stuff is the most common type, but synesthesia can occur between just about any combination of senses or cognitive pathways. And not everyone will experience the same type of synesthesia the same way. So while the soft “ah” sound always seems fire-engine red to one synesthete, it may be cobalt blue for others. Some people with this condition see music – which sounds kind of beautiful, when you think about it. There are less common types, such as lexical-gustatory. People with this condition taste certain flavors, dishes or entire meals based on a picture, word or sound. Smells could have colors and shapes, too. The list goes on. So, this is all fascinating, but how do people get it? Researchers are still working on that one, but they believe the condition tends to be somewhat inherited or genetic, as about 40% of synesthetes have a close relative with synesthesia. Most synesthetes recall having the condition for as long as they can remember. It might sound like people have just made mnemonic connections with sounds, colors or so on, but research shows it is a genuine sensory phenomenon, rather than a memory exercise. For example, if we drew the number five all over a piece of paper – scattered with a few twos, forming a triangle – most people would have a hard time seeing it. They’d have to look closely to search for the twos, and then slowly construct the shape. But a grapheme-color synesthete can see this triangle almost instantly. Researchers think that synesthesia is a kind of cross-wiring in the brain. In grapheme-color synesthetes, seeing a number stimulates your grapheme region and the area of your visual cortex that responds to color stimuli. One theory is that there are increased neural connections in the brain of synesthetes that could've been the result of less "neural pruning" while in utero. Even cooler is that there might be actual anatomical differences in the brains of synesthetes, like increased white and gray matter in the brain. One bit of sad news for all the non-synesthetes. Although one study did find that some exposure to color-letters built up their association, the effect didn't last. So people can’t just “catch” synesthesia. But, hey, it’s not like all synesthetes have a great time. It can be uncomfortable to see a number in the "wrong" color. And one lexical-gustatory synesthete also said that if a certain name doesn't taste “right” to him, he has a hard time liking the person it's attached to. Kevin. And it’s time to talk about drugs. Don’t act like you didn’t know this was coming. Hallucinogens might be one way that synesthesia can be "manufactured." Several drugs can produce vivid synesthesia in non-synesthetes, which might be a key to understanding the condition. One researcher has posited that in non-synesthetes, information in a multisensory area travels back easily to its single-sense area, but in synesthetes it gets a bit mixed up along the way. Hallucinogens may temporarily alter the user’s neurochemistry, confusing those existing connections. I mean, let’s face it, going to a concert might be pretty amazing for people with visually-associated synesthesia. SOURCES: http://science.howstuffworks.com/life/inside-the-mind/emotions/synesthesia.htm/printable http://videos.howstuffworks.com/science-channel/33372-talking-synesthesia-how-it-works-video.htm http://videos.howstuffworks.com/discovery/30572-one-step-beyond-synesthesia-video.htm http://videos.howstuffworks.com/science-channel/33870-when-senses-collide-synesthesia-origins-video.htm http://www.stuffyoushouldknow.com/blog/tag/synesthesia/ http://www.livescience.com/169-rare-real-people-feel-taste-hear-color.html
How Does A Duel Work?
 
03:59
Has someone impeached your honor? Achieve satisfaction through dueling by following these easy steps! Learn more at HowStuffWorks.com: http://people.howstuffworks.com/duel.htm Share on Facebook: https://goo.gl/ZiQWrO Share on Twitter: https://goo.gl/tKsIay Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Hi. I’m Jonathan Strickland. This is BrainStuff. Today’s question: How do duels work? The English word “duel” seems to come from cramming together the Latin words “duo-“, meaning “two”, and “bellum”, meaning war. “Duellum,” or eventually, just “duel.” So a duel is combat between two people. The duel of honor was a specific cultural practice taking place mostly in Europe and the Americas, starting around the Renaissance and fizzling out in the early 20th century. There’s no one list of universal rules, but there were some especially popular guides -- for example, the Irish Code Duello of 1777. Let’s see how a duel according to the Code Duello might go down. First off – who would duel? There were some notable exceptions, but most duels of honor took place between men of the aristocracy. And what could cause a duel? Any insult to someone’s honor. Honor is a difficult concept to define succinctly, but it meant something like “a man’s reputation for respectability and aristocratic virtues.” But whether someone had an affair with your wife or simply made harsh jest of your new powdered wig, honor was on the line. And according to the 1824 “British Code of Duel,” honorable men were not only expected to accept duels when challenged; they were expected to demand them when offended. So: The offended party issues a formal challenge. Depending on the offense, the duel might be averted by an apology. If so, the two parties have to apologize for their offenses in the order they were committed. But according to the Code Duello, some offenses to honor couldn’t be fixed by apology alone. So a personal insult, maybe. But a punch to the nose was a point of no return: You pretty much had to duel to repair your honor. Duels could involve any number of weapons, usually chosen by the person being challenged. In France in 1843 two men reportedly dueled to the death with billiard balls – and yes, one of them was killed by a billiard ball straight to the face. But the two most common dueling weapons were, first, swords, and later, pistols. The two dueling parties usually appointed “seconds.” These were like lieutenants. The seconds had the job of trying to resolve the conflict before it came to violence, and they were also responsible for preparing the duelists’ weapons. You’d think from this arrangement that the seconds would tend to keep cool heads, but according to Rule 25 of the Code Duello, “Where seconds disagree, and resolve to exchange shots themselves, it must be at the same time and at right angles with their principals.” "Principals" meaning duelists - not their own personal philosophies. And honestly, it ends up with a whole lot of people shooting at each other. Many duels didn’t end in death. In fact, in England, between 1760 and 1820, there were 172 known duels (though probably plenty more that were off the books), but only 69 known fatalities from duels. Often, duels using swords could be called off once at least one swordsman had been bloodied. And those who used pistols often intentionally fired wide of the target – though the Code Duello strictly prohibits “dumb shooting or firing in the air,” referring to such practices as “children’s play.” But despite this command, many duelists simply didn’t aim to kill. Crazy duel fact from the 21st century: In 2002, an Iraqi official suggested that Saddam Hussein and George W. Bush could avoid an all-out war if they settled their differences through a one-on-one duel on neutral territory. The White House declined the challenge. SOURCES: http://people.howstuffworks.com/duel.htm/printable http://www.pbs.org/wgbh/amex/duel/sfeature/dueling.html http://www.smithsonianmag.com/history/duel-104161025/?all http://www.newyorker.com/magazine/2007/03/12/en-garde https://www.gwu.edu/~magazine/archive/2005_law_fall/docs/feat_duel.html http://www.pbs.org/wgbh/amex/duel/sfeature/rulesofdueling.html http://www.telegraph.co.uk/news/obituaries/11512352/Lieutenant-Colonel-John-Dymoke-Queens-Champion-obituary.html http://news.bbc.co.uk/2/hi/americas/2297371.stm https://books.google.com/books?id=3UpHXmlYHBcC&pg=PT204&lpg=PT204&dq=Lenfant+and+Melfant&source=bl&ots=iqHwSfrZ0s&sig=9FI0wnYiS5OG3zWRHu31DXSZeRQ&hl=en&sa=X&ved=0ahUKEwiJuLepq4fMAhUX7mMKHUW0CGQQ6AEISDAJ#v=onepage&q=Lenfant%20and%20Melfant&f=false
Why Do People Go Bald?
 
04:18
For most men, losing your hair is an inevitable side effect of aging. Jonathan describes the growth cycle of hair, types of baldness that affect men and women, and how most ladies feel about bald dudes.
What Causes Chapped Lips?
 
03:27
For some people, winter means a daily battle against cracking, scaling or peeling lips. But what actually causes chapped lips? How can you prevent it? Learn more at HowStuffWorks.com: http://health.howstuffworks.com/skin-care/lip-care/tips/5-tips-for-battling-cracked-lips.htm Share on Facebook: https://goo.gl/R2ZwmK Share on Twitter: https://goo.gl/eyBIVF Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com I’m going to go out on a limb here and say you’ve probably had chapped lips at some point. Here’s what’s happening. Your lips are pretty delicate things – this one at the top is your Labium superius oris, and the one at the bottom is your Labium inferius oris. Collectively they form an enormously sensitive, incredibly flexible part of your body. However, they also have some vulnerabilities. For instance, the skin of your lips is different from the rest of your face – let’s take a closer look. Here we go – this is your skin! The outer layer is called the epidermis, and it has a protective covering called the stratum corneum. Underneath your epidermis is another layer of skin, the dermis. Like the rest of your skin, your lips have all three of these layers -- the difference is that the stratum corneum on your lips is way thinner than it is anywhere else on your body. In fact, it’s part of the reason people’s lips have that alluring red or pink pigment. It comes from underlying blood vessels -- red-colored, blood-filled capillaries close to the thin skin on your lips. Next, your lips also don't have the oil and sweat glands that protect other parts of your skin. Their only source of moisture is your saliva, and that's why they can easily become dry and chapped. And that’s usually the culprit here: hydration. We often experience chapped lips in cold weather – not because our lips are allergic to winter or anything, but instead because the outside air tends to be drier, and this also dries out the lips. And this drying out is the leading cause of chapped lips, also known as common cheilitis. Luckily, there are some pretty simple ways to prevent this. First, and no matter what the cause of your chapped lips might be… stop licking them! I know, I know it can be a difficult habit to break. But licking your lips can contribute significantly to dry, cracked skin. The saliva evaporates quickly, taking with it any moisture that was already on your lips and leaving them even drier, especially in winter air. And speaking of amazing segueways, let’s tackle weather-related chapping. If you have very dry air in your house, consider investing in a humidifier. If you’re outside, then protect your lips with a product that contains beeswax or petrolatum, which will help maintain your lips' hydration. If you plan to be out in the sun for awhile, help prevent dryness by using a sunscreen on your lips as well. A lip balm with SPF in it could help address both of these issues at once -- and, as always, drinking plenty of fluids is a great move for your entire body, not just your lips. And that’s it. Well, almost. We didn’t talk about the multiple other causes of chapped lips, or lip balm addiction, or whether some of the ingredients in those things actually cause chapped lips – an interesting little conspiracy theory. SOURCES: http://health.howstuffworks.com/skin-care/lip-care/health/lips-most-sensitive.htm http://health.howstuffworks.com/skin-care/lip-care/health/lips-different-skin.htm http://health.howstuffworks.com/skin-care/lip-care/health/dry-lips-health-problem.htm http://health.howstuffworks.com/skin-care/lip-care/health/cold-temperatures-damage-lips.htm http://www.today.com/id/22505976 http://www.healthline.com/symptom/chapped-lips http://www.medilexicon.com/medicaldictionary.php?t=47434 http://www.medilexicon.com/medicaldictionary.php?t=47448 http://www.webmd.com/beauty/lips-smile/end-chapped-lips http://drtrue.com/2014/02/cheilitis-inflammation-of-the-lips/ THE LIP BALM CONSPIRACY THING: http://lifehacker.com/5974745/know-which-ingredients-in-lip-balm-actually-cause-dry-lips http://www.today.com/style/got-chapped-lips-lip-balm-isnt-answer-I313924 http://www.mayoclinic.org/diseases-conditions/dry-skin/expert-answers/chapped-lips/faq-20057819 http://health.howstuffworks.com/skin-care/lip-care/tips/10-tips-for-battling-dry-lips.htm
Does The Human Body Really Replace Itself Every 7 Years?
 
02:37
The short answer is “no.” Tune in to learn how long it really takes, plus how nuclear weapons led scientists to the solution. Learn more at HowStuffWorks.com: http://science.howstuffworks.com/life/cellular-microscopic/does-body-really-replace-seven-years.htm Share on Facebook: http://goo.gl/55pmys Share on Twitter: http://goo.gl/v2s366 Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Today’s question: Does your body really replace itself every 7 years? The short answer is “no,” but don’t worry: This isn’t a case of chicanerous researchers pulling the wool of shoddy science over your eyes. Your body mostly replaces itself every 7 to 15 years. Some bits are never replaced. Others, like the lining of your stomach and intestines, are renewed much faster. Due to constant wear and tear from the process of digestion, these cells have an average lifespan of just 5 days! Yes, the organs that work the hardest have the fastest changeover. You get a whole new skin every 2 to 4 weeks. Your red blood cells last less than half a year – not bad, considering that their route through your circulatory system is about a thousand miles. And your liver renews itself at least once every couple of years. As the human body’s detoxifier, it goes through a lot. Other tissues take longer to completely replenish themselves. Like your bones. Skeletal cells die and new ones grow constantly, but the complete process takes about 10 years. (And the process slows down as we get older, which is why our bones tend to get weaker as we age.) And, like I said, some parts of your body stay with you for life. The cells on the inner lens of your eye formed when you were just an embryo. Your tooth enamel wears down with use, never to return. And evidence indicates that you can’t regrow the neurons of your cerebral cortex. Its loss can lead to diseases like dementia. Luckily, other parts of your brain do regenerate. Like the hippocampus, which helps us create memories, and the olfactory bulb, which helps us smell. So how do we know all this? Turns out, it’s thanks to our old pal nuclear weapons testing. Yeah! High-fives for radioactive stuff being released into the atmosphere! No, really: Aboveground nuclear detonations during World War II and the Cold War spiked Earth’s air supply with extra carbon-14. It’s been declining back toward the norm at a predictable rate since the 1960s. Which means that you can use the amount of it present in any given tissue sample to determine when those cells were born. More carbon-14 means older cells. SOURCES: http://science.howstuffworks.com/life/cellular-microscopic/does-body-really-replace-seven-years.htm/printable http://www.nytimes.com/2005/08/02/science/02cell.html?pagewanted=all&_r=0 http://www.sciencedirect.com/science/article/pii/S0092867413005333 http://ac.els-cdn.com/S0092867405004083/1-s2.0-S0092867405004083-main.pdf?_tid=b128d0a8-9b4e-11e4-8103-00000aacb362&acdnat=1421172481_5286828a6b59ff28fb8e5b9fb5a7d3a3 http://www.state.gov/t/isn/4797.htm http://science.howstuffworks.com/life/inside-the-mind/human-brain/brain8.htm/printable
How Do Polygraph Machines Work?
 
03:12
Also known as 'lie detectors,' polygraphs are used to record an individual's vital signs, such as breathing rate, pulse, and so forth. Check out this episode of BrainStuff to learn more about polygraphs and the art of lie detection. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Are Pop Rocks Dangerous?
 
03:41
Did Pop Rocks really blow the door off of a delivery van? Has anyone ever died from eating these popping bits of sugar? The answers might surprise you. Join Josh as he looks into the truth behind the rumors surrounding the uniquely (and surprisingly loud) candy called Pop Rocks. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Download the New TestTube iOS app! http://testu.be/1ndmmMq Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Are Stupid People More Confident?
 
03:20
We've all heard about the supposed relationship between confidence and knowledge - but is it true? Two researchers think they've found the answer. Learn more at HowStuffWorks.com: http://people.howstuffworks.com/decisions-groups-decisions-alone.htm Share on Facebook: http://goo.gl/SBM7wy Share on Twitter: http://goo.gl/tz0IoH Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Hey, BrainStuff, it’s me, Ben. If you’re like most people, you think you’re very good at some things, and are able to admit you’re less good at others. You probably think you’re superbly talented in one or two areas - and hey, you might be right. You try to be honest with yourself about your strong points and your weak ones. You likely shake your head in pity at people you see as, well, stupid. “Why do they keep dumbing everywhere?” you ask yourself, “Why don’t they understand that they’re bad at doing stuff? There is an answer, but you might not like it. And this answer doesn’t just apply to people you think of as “dumb”. It applies to everyone on Earth… including you and me. It’s not a matter of intelligence, necessarily– a difficult thing to measure– but it is related to “competence”, the ability to do something well. In 1999 a psychologist named David Dunning and his grad assistant Justin Kruger tested a group of students in several categories: “the ability to think logically, to write grammatically, and to spot funny jokes”. They also asked the students to rate their skills in these categories. That’s when they noticed something weird. The people scoring below average on these tests weren’t just incompetent in these categories – they also didn’t know they were incompetent. And here’s the kicker: the less competent they were, the MORE competent they ranked themselves. This is a phenomenon called “illusory superiority” (which sounds like the name of a Radiohead B-Side, but isn’t, as far as we know). Instead, this is a cognitive bias wherein people tend to rate their own abilities as above-average. You know, like how everyone’s thinks they’re a good driver or believes they have a great sense of humor. Multiple studies have proven this effect in everything from firearms to college debates and med students’ opinions of their interviewing skills. It doesn’t seem to matter what specific skill we’re talking about – the less a person knows about it, the more likely they are to overestimate their knowledge. While Dunning and Kruger popularized this effect in modern society, they weren’t the first people to notice the relationship between confidence, modesty and skill. Philosophers throughout the ages have contemplated this idea, like Bertrand Russell, who famously wrote “The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt.” And here’s another weird thing. People with actual competency are likely to actually underestimate their abilities. Researchers believe this modesty comes because competent people are more aware of how much they don’t actually know, as well as their field in general. They also consistently overestimate the performance ability of others. It all goes back to one primary thing – metacognition. Metacognition is the ability to be aware of and understand your own thought process. In other words, the ability to think about how you think. People tend to evaluate themselves through what Dunning and Kruger call a “top-down” approach. Instead of objectively measuring their performance, people start with their preconceived notions of their skill and use that belief to evaluate their performance. SOURCES: http://psych.colorado.edu/~vanboven/teaching/p7536_heurbias/p7536_readings/kruger_dunning.pdf http://people.howstuffworks.com/human-intelligence-info.htm http://theness.com/neurologicablog/index.php/lessons-from-dunning-kruger/ http://psycnet.apa.org/?&fa=main.doiLanding&doi=10.1037/0022-3514.77.6.1121 http://petapixel.com/2014/10/13/dunning-kruger-peak-photography/ http://www.psych.nyu.edu/jost/Zuckerman%20&%20Jost%20(2001)%20What%20Makes%20You%20Think%20You're%20So%20Popular1.pdf
How Do TV Ratings Work?
 
02:42
The future of your favorite TV shows hinges on their ratings – but what is a rating, and where does it come from? Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Learn more at HowStuffWorks.com: http://electronics.howstuffworks.com/question433.htm Share on Facebook: http://goo.gl/BMQidC Share on Twitter: http://goo.gl/Rd0RDA Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com SOURCES: http://electronics.howstuffworks.com/question433.htm http://people.howstuffworks.com/culture-traditions/tv-and-culture/dvr-viewings-tv-ratings1.htm http://splitsider.com/2011/01/why-nielsen-ratings-are-inaccurate-and-why-theyll-stay-that-way/ http://www.nytimes.com/2011/01/03/business/media/03ratings.html?_r=0 http://sites.nielsen.com/90years/ http://www.nielsen.com/content/corporate/us/en/about-us.html CREDITS: Arthur Nielsen photo: http://www.quotessays.com/bio/arthur-c-nielsen.html
How Do We Know What Dinosaurs Looked Like?
 
03:19
Can we really reconstruct a dinosaur’s appearance from a bunch of million-year-old fossils? How? Learn more at HowStuffWorks.com: http://science.howstuffworks.com/environmental/earth/geology/dinosaur-feather.htm Share on Facebook: http://goo.gl/yxg5fB Share on Twitter: http://goo.gl/g9f2L2 Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com CREDITS: Dakota fossil photos by Kabacchi (Hadrosauridae (Dakota) - 01, 03 Uploaded by FunkMonk) [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons SOURCES: http://www.mnh.si.edu/exhibits/backyard-dinosaurs/faq.cfm#2 http://www.slate.com/articles/health_and_science/science/2012/11/thanksgiving_turkey_is_a_dinosaur_the_sharks_alligators_beetles_and_other.html http://www.slate.com/articles/health_and_science/science/2012/09/creationists_and_dinosaurs_answers_in_genesis_teams_with_dissident_scientists_to_deny_feathered_dino_fossil_record.html http://phenomena.nationalgeographic.com/2012/12/31/hooray-for-dinofuzz/ http://phenomena.nationalgeographic.com/2014/07/24/fluffy-dinosaur-raises-questions-about-the-origin-of-dinofuzz/ http://phenomena.nationalgeographic.com/2014/10/10/getting-to-the-root-of-fur/ http://www.cbsnews.com/news/dinosaur-skin-color-revealed/ http://www.popsci.com/science/article/2012-03/reconstructed-dinosaur-four-iridescent-wings http://www.popsci.com/science/article/2013-04/particle-accelerator-look-dino-skin-color http://science.howstuffworks.com/environmental/earth/geology/soft-tissue-dinosaur-fossil.htm http://science.howstuffworks.com/environmental/earth/geology/dinosaur-feather.htm/printable http://science.howstuffworks.com/environmental/earth/geology/dinosaur.htm/printable http://www.mnh.si.edu/exhibits/backyard-dinosaurs/faq.cfm#13 http://science.time.com/2014/02/12/dinosaurs-colorful-feathers/ http://news.nationalgeographic.com/news/2014/02/140212-bird-dinosaur-mammal-color-metabolism/
Why Are There So Many Different Kinds Of Milk?
 
04:56
Josh explains the difference between common types of milk, looking at calories, fat and the rest of their composition.
Why Are Your Eyes That Color?
 
03:41
What makes eyes brown, blue, green, and so on? Share on Facebook: http://goo.gl/Pfb2NK Share on Twitter: http://goo.gl/3GGFbq Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com
How Much Oxygen Does a Person Consume in a Day?
 
01:49
Ever wonder how much oxygen you breathe in a day? Watch this episode of BrainStuff and find out! Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff Watch More of Ben on Stuff They Don't Want You To Know: http://www.youtube.com/conspiracystuff
What Do Those Tabs On Rearview Mirrors Actually Do?
 
03:12
Sure, rearview mirrors are cool -- but how do they actually work? How can the same piece of glass have two different amounts of reflection? Join Josh as he explains the science behind these handy devices. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Download the New TestTube iOS app! http://testu.be/1ndmmMq Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Is Glass Really A Liquid?
 
02:13
You may have heard (or even read in a textbook) that glass is a liquid. Or that it's a solid. The truth is a little more complicated, but Lauren is here to explain. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff Script: Hi. I’m Lauren, this is BrainStuff, and here’s today’s question: “Is glass a liquid or a solid?” If you’ve ever looked at the windowpanes in an old building, you may have noticed that the glass was rippley, and thicker towards the bottom of the pane. And you might’ve lept, gazelle-like, to the logical-sounding conclusion that the glass had flowed into that shape very slowly over a couple of centuries. You might’ve even read it in a textbook. The truth is that the glass has always been that way. OK, so, up through the 1800s, panes of glass were made by hand – glassblowers used what’s called the crown process. They’d take a flattened bubble of very hot glass and rotate it fast so that the centrifugal force would spin it out into a large, mostly flat disc. The disc would be thicker at the edges, and each pane cut from it was bound to be a little lumpy. And workers tended to install them with the thicker side down – probably because the slightly larger edge provided better balance. So the glass in those old panes isn’t flowing – at least, not that researchers can discern. They’ve looked at samples of glass from 2000 years ago and haven’t found telltale evidence of flow. Scientifically speaking, glass is considered an amorphous solid – that means its atoms and molecules are locked into place like in a solid – like in ceramics, really. But those molecules are arranged more randomly than in most solids – more similar to a liquid. If you wanna get into semantics, you could sorta call glass a supercooled liquid – that’s a liquid cooled to below its melting point carefully so that it doesn’t crystalize. And that’s part of making glass – but at that stage, it’s still hundreds of degrees above room temperature. It’s then cooled until it transitions into the rigid amorphous solid that we know and love. So you might say glass is its own state of matter, neither a liquid nor a solid. Sources: http://math.ucr.edu/home/baez/physics/General/Glass/glass.html http://www.scientificamerican.com/article.cfm?id=fact-fiction-glass-liquid http://dwb.unl.edu/Teacher/NSF/C01/C01Links/www.ualberta.ca/~bderksen/florin.html http://www.howstuffworks.com/science-vs-myth/everyday-myths/10-false-facts4.htm http://science.howstuffworks.com/question404.htm/printable http://www.britannica.com/EBchecked/topic/144474/crown-glass
Why Do I Hate The Sound Of My Own Voice?
 
02:12
The recorded sound of your voice usually makes you cringe because of two ways vibrations reach your ear. Share on Facebook: http://goo.gl/RM7uL9 Share on Twitter: http://goo.gl/Lp4CxM Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Have you ever heard a recording of yourself played back and thought, "Ugh. Why do I sound like that?!" It’s weird right? Usually our voices sound deeper but when played back the way everyone else hears them they are higher and tinnier. Why does it sound so different? And why do we hate it so much? The sound of your voice reaches your inner ear in two different ways. The vocal folds in your throat vibrate, creating sound waves that travel through the air. But those sound vibrations also conduct through your body, particularly through your skull and bones. Our skulls lower the frequency of these later vibrations as they bounce around inside our throat, mouth and neck before reaching the ear's cochlea through the fleshy tissue in our heads. The surrounding bones spread out the vibrations, lower their pitch and enhance the lower-frequency vibrations so your voice sounds fuller and deeper. When we hear our voice played back on a recording, we don't get it filtered through flesh and bone. What we're hearing then is only the air-conducted sound of our voice as waves of pressure. These vibrations are caught by our outer ears, and then transmitted through our eardrums, where they vibrate three bony ossicles before reaching the cochlea. In both cases, the cochlea converts these vibrations into impulses that are sent to the brain. But with the elimination of the bone-conducted sound we end up hearing our voice the way everyone else hears it. Most of us have had this experience and hate it. We're used to the combination of the air-conducted and bone conducted sounds of our voice. It’s what we've lived with all our lives. So of course it's unsettling to hear something so different than we're used to. But remember, this is how your friends have been hearing you your whole life. To them, it’s normal. So relax and rest easy knowing that everyone cringes at the sound of their own voice. SOURCES: https://www.youtube.com/watch?v=L2wThQljxcY http://mentalfloss.com/article/12796/why-do-our-voices-sound-different-us-other-people http://www.scientificamerican.com/article/why-does-my-voice-sound-different/ http://www.bbc.com/future/story/20130913-why-we-hate-hearing-our-own-voice http://www.popsci.com/scitech/article/2009-06/why-your-voice-sounds-different-recordings http://bodyodd.nbcnews.com/_news/2013/04/02/17557410-why-you-hate-the-sound-of-your-own-voice
Why do feet stink?
 
02:32
What causes stinky, smelly feet? Sweat and bacteria. Find out exactly how bacteria turn sweat into malodorous feet in this episode. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
Why Do We Put Diamonds On Engagement Rings?
 
02:32
The tradition of diamond engagement rings is actually less than 100 years old. How did it become so popular in such a short time? Learn more at HowStuffWorks.com: http://science.howstuffworks.com/environmental/earth/geology/diamond5.htm Share on Facebook: http://goo.gl/o0KmJ6 Share on Twitter: http://goo.gl/eGnFyy Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Today’s question: Why do most engagement rings feature diamonds? Why not emeralds, or pyrite, or beef jerky nuggets? Turns out, you can trace this precious tradition back to ... an ad campaign. Before the 1940s, opals, rubies, sapphires, and turquoise were way more popular than diamonds as engagement stones. In 1939, only some 10 percent of U.S. engagement rings bore diamonds. And the jewels being used were smaller and of poorer quality than the stones common today. But by the end of the 20th century, about 80 percent of U.S. engagement rings featured diamonds. Enter an ad campaign. In the 1930s, the world’s leading diamond mining and trading company, De Beers, found itself in a tight spot. De Beers has been in the business, in one form or another, since just after the discovery in 1870 of huge deposits of diamonds in South Africa. Before then, diamonds were truly scarce; they had to be panned from rivers. With this new supply, De Beers flourished. Well, it was really the supply plus careful corporate consolidation and market control. But yes, they flourished. That is, until the Great War, the ensuing Great Depression, and the looming promise of a second world war sent the demand for diamonds into freefall. So in 1938, De Beers hired ad agency N. W. Ayer to research the market and produce a comprehensive U.S. ad campaign: print, radio, and celebrity publicity. Print ads compared diamonds to paintings by Picasso and Dali – unique and precious. They commissioned portraits of famous couples who’d recently gotten engaged – all sporting diamonds. In 1947, they launched the slogan “A Diamond Is Forever”. By that time, the number of diamonds being purchased for engagement rings in the U.S. had already tripled. It was – and is – a brilliant campaign. Pun intended, for once. It set up diamonds as a near-indispensable part of engagement traditions. And as heirlooms to be cherished and kept – not to be resold back into the market. Meaning more diamonds would be bought, and almost all of them new. In the 1960s, De Beers and N. W. Ayers began educating the public about the quality of diamonds, encouraging the purchase of more expensive jewels. And their product placement continues to this day as they loan out extravagant pieces to Hollywood stars for films and the red carpet alike. CREDITS: Vintage De Beers ads from Vintage Ads: http://vintage-ads.dreamwidth.org/2228174.html N.W. Ayer Ad from MagazineArt.org: http://www.magazineart.org/main.php/v/ads/banksinsurancebrokers/advertisingagencies/N_+W_+Ayer+and+Son+-1920A.jpg.html Ad of man holding diamond ring from Art of Manliness: http://www.artofmanliness.com/2014/06/11/5-alternatives-to-the-diamond-engagement-ring/ SOURCES: http://www.theatlantic.com/magazine/archive/1982/02/have-you-ever-tried-to-sell-a-diamond/304575/?single_page=true http://science.howstuffworks.com/environmental/earth/geology/diamond.htm/printable http://www.bain.com/Images/PR_BAIN_REPORT_The_global_diamond_industry.pdf http://www.nytimes.com/2013/05/05/fashion/weddings/how-americans-learned-to-love-diamonds.html?pagewanted=all&_r=0 http://www.washingtonpost.com/opinions/why-a-diamond-is-forever-has-lasted-so-long/2014/02/07/f6adf3f4-8eae-11e3-84e1-27626c5ef5fb_story.html
Why Can't People Remember Being Born?
 
03:36
You probably remember your 18th birthday, but not your first – or your zeroth. Why is that? Learn more at HowStuffWorks.com: http://science.howstuffworks.com/life/inside-the-mind/human-brain/remember-birth.htm Share on Facebook: https://goo.gl/hiKxeT Share on Twitter: https://goo.gl/E3UcM0 Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com A lot of things are easy to remember: My high school graduation. My first summer job. That time I got arrested for emptying a bunch of Jello packets into Bryan Cranston’s gas tank – long story. It doesn’t take a scientist to notice that adults don’t generally remember things that happened before the age of about 3 or 4. Why is that? Why can’t we remember the earliest events in our lives, up to and including birth? OK, here’s an experiment: Try to remember what happened the last time you ate a burrito. Where were you? Who was with you? Was the burrito full of spiders? These kinds of memories – being able to recall details of a particular event in the past – are called episodic memories. A person at age 60 will usually have some episodic memories from age 30 – she might not get all the details right, but she will be able to recall some events and explain what happened. But if you take that same person at age 30 and ask her to describe something that happened during her first year of life, you’ll typically get nothing at all. Sigmund Freud referred to this hole in our memory as “childhood amnesia,” or “infantile amnesia.” Freud, being Freud, explained it by saying we needed to repress memories from infancy because of their inappropriate or traumatic sexual content. But sometimes a blank is just a blank, and contemporary scientists don’t tend to throw in with Freud on this one. Another hypothesis that used to be popular says that babies can’t form episodic memories until they develop certain cognitive capacities, like language. But there’s a major problem with the language-based hypothesis: Experiments have shown that animals like mice also display both long-term memory and infantile amnesia. Since childhood amnesia crosses species lines, it’s probably something to do with brain biology rather than language. One possible answer would be to say that baby brains simply can’t make memories. It’s true that memory encoding isn’t as efficient in infant brains as it is in the brains of older children or adults – possibly because the prefrontal cortex of a baby’s brain hasn’t reached maturity yet. But recent studies have shown that very young children can form some memories, leading scientists to think it’s not that we don’t make memories early in life, but that after a certain point, we can’t access them. The memories are made, but something happens to them: They get erased, or put behind some kind of memory blockade. Patricia Bauer and Marina Larkina of Emory University have led research on this hypothesis: For example, in one study, researchers recorded children at age 3 describing a recent event, like a trip to a theme park. Years later, the researchers followed up with those same children to see how much they remembered. At ages 5, 6 and 7, the children could recall more than 60 percent of the earlier events, but by ages 8 and 9, their recall was less than 40 percent. More research of this kind is needed, but this looks like watching the onset of childhood amnesia as it happens. Another recent study has considered the role of neurogenesis in the hippocampus. The hippocampus is a part of the brain that’s crucial for creating and storing episodic memories. If you didn’t have either of your hippocampi, you could end up like the guy in “Memento” – unable to make new episodic memories. Neuroscientists Sheena Josselyn and Paul Frankland have proposed a theory that childhood amnesia happens because of rapid formation of new cells in the hippocampus when children are young. This is known as hippocampal neurogenesis. Basically, while your brain is manufacturing lots of the cells you will use to make memories for the rest of your life, it wipes away or obscures the memories you already created as a young child. SOURCES: http://www.tandfonline.com/doi/full/10.1080/09658211.2013.854806 http://learnmem.cshlp.org/content/19/9/423.short http://science.howstuffworks.com/life/inside-the-mind/human-brain/remember-birth.htm/printable http://www.livescience.com/32963-why-dont-we-remember-being-babies.html http://www.nimh.nih.gov/about/director/2013/infantile-amnesia.shtml http://www.npr.org/blogs/health/2014/04/08/299189442/the-forgotten-childhood-why-early-memories-fade https://www.sciencenews.org/article/birth-new-brain-cells-might-erase-babies%E2%80%99-memories http://www.scientificamerican.com/article/why-can-t-you-remember-being-a-baby/ http://www.apa.org/science/about/psa/2004/12/bauer.aspx
How Do GPS Coordinates Work?
 
04:15
So you’ve seen those location-tagging numbers on maps and GPS devices before, but do you actually know what they mean? Brainstuff is here to fill you in. Learn more at HowStuffWorks.com: http://electronics.howstuffworks.com/gadgets/travel/gps.htm Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com SOURCES: https://www2.usgs.gov/faq/categories/9794/3022 http://maps.nationalgeographic.com/downloads/Map_Skills_Booklet.pdf https://www.britannica.com/place/Greenwich-meridian http://astro.unl.edu/naap/motion1/tc_units.html https://pubs.usgs.gov/fs/2001/0077/report.pdf https://www.fcc.gov/media/radio/dms-decimal
How Do You Find Water In The Wild?
 
03:43
In case you ever get stranded in the wild without an obvious source of fresh water, here are a few things you can do to collect some. Learn more at HowStuffWorks.com: http://adventure.howstuffworks.com/survival/wilderness/how-to-find-water.htm/printable Share on Facebook: https://goo.gl/lAapqo Share on Twitter: https://goo.gl/00Tvuu Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Hey BrainStuff, Jonathan here. Lots of situations can leave you stranded in the wild without supplies: Camping miscommunications, unexpected side quests, alien abductions with imprecise return drops, and so on. Whatever the reason you find yourself out there, you’ll need to find water. A minimum of two quarts per day to maintain good health – that is, to keep your blood circulating. Which you want to do. And that brings us to today’s question: How do you find water in the wild? But first, I should mention that this information is for your education only. Legally speaking, I can’t recommend that you do anything I say. Let’s assume that you can’t find any large sources of fresh water: There’s not a raincloud in the sky, and no streams, rivers, or lakes nearby. You can dig a well. Look for mud, or damp soil in a dry riverbed -- there may be groundwater near the surface. Dig a hole about a foot wide and a foot deep. If there’s water, your well will start filling up. Even in the desert, you can try digging at the low point between dunes, near vegetation. Put rocks in the bottom of your well to keep sediment from stirring up into the water, and line the sides with wood to prevent the walls from caving in. Well water needs to be purified before you drink it. Give it a boil for 10 minutes. Even water that looks clean can harbor nasty microbes that will make you sicker than I get after I have shrimp. But if your wells turn up dry, you can create structures to collect water from thin air. Like a solar still. You’ll need some plastic sheeting, a container to collect the water, and a rock. Having a length of tubing or some definitely-non-poisonous vegetation would be a bonus. Choose a damp bit of ground that gets sunlight for most of the day. Dig a bowl-shaped hole about 3 feet across and 2 feet deep. In the bottom, dig out enough space to place your container. If you have a tube, place one end at the bottom of the container and secure the other end on the surface outside the hole. If you have some leaves or other greenery that you know for sure are not toxic, tear them up and add them to the walls of the bowl. Place the plastic loosely over the hole and hold down the edges with rocks. But, not the one you've put aside. That one, you want to put in the center of the sheet so that it sags in a little more than a foot, directly over the container. Add more rocks and soil to the edges of the sheet for stability. The heat of the sun will evaporate moisture in the ground, producing condensation on the plastic. It’ll drip and collect in your container, and you can either sip it directly through your tube or retrieve the container at sunset. If your energy is low, you'll want to avoid all that digging. The transpiration technique yields less water, but all it requires is tying a knot in a plastic bag. Find a definitely-non-poisonous leafy tree or shrub that will be in the sun for most of the day. Tie the bag around a branch. Over the course of the day, the plant will ‘exhale’ (or transpire) water vapor that’ll collect at the bottom of the bag. Untie it or poke a hole in it to collect the water, then tie it off again and reuse the bag. Plants transpire a lot – about 10 percent of the moisture in our air comes from transpiration. Water you get from a solar still or transpiration should be safe to drink, but it never hurts to give it a boil. SOURCES: http://adventure.howstuffworks.com/survival/wilderness/how-to-find-water.htm/printable http://water.usgs.gov/edu/watercycletranspiration.html http://www.practicalsurvivor.com/transpirationbag
Can Water Go Bad?
 
03:14
Many people store water for emergencies -- but is it true that water sitting for too long will go bad? Listen in as BrainStuff explains it for you. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff
How Do Antiperspirants Work?
 
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Every day, millions of people safeguard themselves against excessive sweat with a quick roll of antiperspirant. But what does this stuff do, exactly? Join HowStuffWorks as we answer engaging, everyday science questions, demystifying the amazing world around you. Learn more at HowStuffWorks.com: http://health.howstuffworks.com/skin-care/underarm-care/problems/question627.htm Share on Facebook: http://goo.gl/JOSgRf Share on Twitter: http://goo.gl/pm4puA Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com SOURCES: http://health.howstuffworks.com/skin-care/underarm-care/tips/deodorant-antiperspirant.htm/printable “Are clinical strength antiperspirants really any stronger?” http://health.howstuffworks.com/skin-care/underarm-care/tips/clinical-strength-antiperspirant.htm/printable “Do you need a prescription antiperspirant?” http://health.howstuffworks.com/skin-care/underarm-care/problems/prescription-antiperspirant.htm/printable “What is in an antiperspirant that stops sweat?” http://health.howstuffworks.com/skin-care/underarm-care/problems/question627.htm Is antiperspirant toxic? http://health.howstuffworks.com/skin-care/underarm-care/tips/is-antiperspirant-toxic.htm/printable
What Determines Your Hair Color?
 
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There's a lot of natural variation in the color of human hair. What's the physical explanation for the difference? Learn more at HowStuffWorks.com: http://science.howstuffworks.com/innovation/everyday-innovations/hair-coloring.htm Share on Facebook: http://goo.gl/CbE4Ks Share on Twitter: http://goo.gl/Gs2h7P Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Sometimes, you’re right in the middle of cleaning out the drain in the shower and you start pondering questions like, “Why is my hair a different color from my mom’s hair, or my neighbor’s hair, or my roommate’s disgusting, soggy, three-foot-long, wolf-tail drain-wad? What’s the real difference between blonde hair, black hair, red hair, and everything in between?” The main structural ingredient in human hair is a protein called keratin. It’s what your hair and fingernails are made of, but also what’s behind the silky sheen of wool, bear claws and horse hooves. Mmm, don’t you just want to run your fingers through those hooves? But keratin on its own is not very colorful. And if all humans had in our hair was keratin, we’d look like 18th-century French aristocrats in powdered wigs, because we’d all have the same sort of white, colorless hair. But, keratin is not the only ingredient in human hair. To create natural color, you need to add pigment. This is done by cells in the skin called melanocytes. These melanocytes create the natural pigment known as melanin and deliver it to the cells that create the keratin for your hair. This melanin comes in two varieties: eumelanin and pheomelanin. Eumelanin is a dark pigment that gives hair a brown or black color. Pheomelanin is a lighter pigment that gives hair a red, orange or yellow-ish color. Both of these are present in varying degrees – a person might have a little of each, or a lot of one and almost none of the other. So someone with black or dark brown hair probably has a lot of eumelanin. A redhead has a lot of pheomelanin, and blondes don’t have very much of either one. So what happens when we get older and start to “go gray”? You can probably guess: over time, melanocytes start to die off, and any new hair that grows has less pigment, so it looks gray or white. But! you might be asking: “What determines the eumelanin to pheomelanin mixture to begin with? Who writes that recipe?” Primarily, it’s your genes. For example: the melanocortin 1 receptor, or MC1R, gene. When the protein associated with this gene is active in melanocytes, it stimulates them to make eumelanin – the pigment that colors black or brown hair. When MC1R is not active in the melanocyte cells, they make mostly pheomelanin instead, and Hello Weasleys. But! The MC1R gene is not the only genetic factor that controls hair color – like most of your traits, hair color is actually affected by more than one genetic variable. SOURCES: http://www.scientificamerican.com/article/fact-or-fiction-stress-causes-gray-hair/ http://www.thenakedscientists.com/HTML/questions/question/1000018/ http://www.britannica.com/EBchecked/topic/315321/keratin http://www.scientificamerican.com/article/why-does-hair-turn-gray/ http://ghr.nlm.nih.gov/gene/MC1R http://news.sciencemag.org/biology/2014/06/genetics-blond-hair http://news.nationalgeographic.com/news/2014/06/140601-blond-hair-color-gene-mutation-science/ http://www.nature.com/ng/journal/v46/n7/pdf/ng.2991.pdf http://www.britannica.com/EBchecked/topic/647753/wool
What Would Space Do To The Human Body?
 
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Space without a suit? You’ll probably die from the lack of pressure in a vacuum. But other extreme hazards won’t help either. Learn more at HowStuffWorks.com: http://science.howstuffworks.com/question540.htm Share on Facebook: https://goo.gl/CeaQIU Share on Twitter: https://goo.gl/fQyVHl Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com Remember that time in “Battlestar Galactica” when that one character was blown out an airlock into outer space without a suit? No? What about when it happened in “2001?” Or “Guardians of the Galaxy?” Or “Sunshine?” Yes, we all dream about travelling in space. But if movies are any indication, we spend almost as much time thinking about flying around up there without a suit on! So let’s answer this question once and for all. What would space actually do to a human body? Well here’s the good news: you wouldn’t die instantly. Yeah, you might actually survive for a little bit out there. How do we know? Because somebody tested it out… on dogs. In 1965, researchers at Brooks Air Force Base in Texas exposed several dogs to a near vacuum. The dogs survived for up to 90 seconds. But if they went two minutes or more they died when repressurized. If your first thought is, “They did this to dogs?!” I’m right there with you. Researchers at NASA did the same to chimpanzees in the late 1960s, finding that they could last up to 3.5 minutes. And then there’s been a few accidents where people got de-and-then-re-pressurized, like a technician at Johnson Space Center who lost consciousness after 12 seconds. This was just before the moisture on his tongue began to boil. See, without air pressure to keep your precious bodily fluids in their liquid state they would rapidly lose heat energy before they froze and then evaporated totally. This isn’t the worst thing the lack of pressure can do to you either. The gases inside you would expand, causing you to swell up like a balloon in a Thanksgiving Day parade. This includes air and gas bubbles formed from your boiling body fluids. That effect is called “ebullism,” which can block your bloodstream with these bubbles. And that would cause you to pass out in about 15 seconds from the lack of blood flowing to your brain. Your skin’s blood vessels would burst. Your internal organs would also swell and likely tear. But you wouldn’t explode like in “Total Recall.” You’d just stretch painfully until you died. Keep in mind, so far we’ve only been talking about the effects to a body in a vacuum. In actual space there are even more hazards to deal with. Depending on your location you could either be exposed to a star’s thermal radiation at around 120 degrees Celsius, or your own body heat would radiate away in the shade at around -100 degrees. Finally, there’s the obvious lack of oxygen. Normally you could hold your breath for several minutes. But remember, without pressure, that whole boiling effect would diffuse the oxygen from your blood. So again, after about 15 seconds you’d pass out. And don’t try to hold your breath either. It would just expand with the other gases, rupturing your lungs. All-in-all these things would probably kill you in less than a minute. SOURCES: http://science.howstuffworks.com/suitless-space-walk.htm http://www.scientificamerican.com/article/survival-in-space-unprotected-possible/ http://www.slate.com/articles/news_and_politics/explainer/2007/08/can_you_survive_in_space_without_a_spacesuit.html http://www.iflscience.com/space/what-would-happen-your-body-space-without-spacesuit http://www.nsbri.org/DISCOVERIES-FOR-SPACE-and-EARTH/The-Body-in-Space/ http://sitn.hms.harvard.edu/flash/2013/space-human-body/ http://science.howstuffworks.com/question540.htm http://www.space.com/14719-spacekids-temperature-outer-space.html
Why Do We Get Bags Under Our Eyes?
 
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We all get bags under our eyes that make us look tired. Here's how it inevitably happens and some remedies to look your best.​ Join HowStuffWorks as we answer engaging, everyday science questions, demystifying the amazing world around you. Learn more at HowStuffWorks.com: http://health.howstuffworks.com/skin-care/problems/beauty/what-causes-bags-under-eyes.htm Share on Facebook: http://goo.gl/4T7Xi0 Share on Twitter: http://goo.gl/8hu8sE Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com SOURCES: http://health.howstuffworks.com/skin-care/problems/beauty/what-causes-bags-under-eyes.htm http://www.mayoclinic.org/diseases-conditions/bags-under-eyes/basics/symptoms/con-20034185 http://health.howstuffworks.com/skin-care/problems/treating/get-rid-of-bags-under-eyes3.htm http://www.webmd.com/beauty/eyes/banish-the-bags-under-your-eyes?page=2 Right under your very eyes. By: Roach, Mary, Health (Time Inc. Health), 1059938X, Nov/Dec97, Vol. 11, Issue 7 Petty, L. (2011). The eyes have it: Keep them healthy and bright. Alive: Canada's Natural Health & Wellness Magazine, (348), 101-104.
How many balloons would it take to lift you off the ground?
 
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Balloons are often filled with helium, which has a lifting force of one gram per meter. It's possible to assemble enough balloons to lift yourself from the ground -- but how many balloons does it take? Tune into this episode to learn more. Whether the topic is popcorn or particle physics, you can count on the HowStuffWorks team to explore - and explain - the everyday science in the world around us on BrainStuff. Watch More BrainStuff on TestTube http://testtube.com/brainstuff Subscribe Now! http://www.youtube.com/subscription_center?add_user=brainstuffshow Watch More http://www.youtube.com/BrainStuffShow Twitter http://twitter.com/BrainStuffHSW Facebook http://facebook.com/BrainStuff Google+ http://gplus.to/BrainStuff