What Happens When You Flush an Airplane Toilet?

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iStock

For millions of people, summer means an opportunity to hop on a plane and experience new and exciting sights, cultures, and food. It also means getting packed into a giant commercial aircraft and then wondering if you can make it to your next layover without submitting to the anxiety of using the onboard bathroom.

Roughly the size of an apartment pantry, these narrow facilities barely accommodate your outstretched knees; turbulence can make expelling waste a harrowing nightmare. Once you’ve successfully managed to complete the task and flush, what happens next?

Unlike our home toilets, planes can’t rely on water tanks to create passive suction to draw waste from the bowl. In addition to the expense of hauling hundreds of gallons of water, it’s impractical to leave standing water in an environment that shakes its contents like a snow globe. Originally, planes used an electronic pump system that moved waste along with a deodorizing liquid called Anotec. That method worked, but carrying the Anotec was undesirable for the same reasons as storing water: It raised fuel costs and added weight to the aircraft that could have been allocated for passengers. (Not surprisingly, airlines prefer to transport paying customers over blobs of poop.)

Beginning in the 1980s, planes used a pneumatic vacuum to suck liquids and solids down and away from the fixture. Once you hit the flush button, a valve at the bottom of the toilet opens, allowing the vacuum to siphon the contents out. (A nonstick coating similar to Teflon reduces the odds of any residue.) It travels to a storage tank near the back of the plane at high speeds, ready for ground crews to drain it once the airplane lands. The tank is then flushed out using a disinfectant.

If you’re also curious about timing your bathroom visit to avoid people waiting in line while you void, flight attendants say the best time to go is right after the captain turns off the seat belt sign and before drink service begins.

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Is the Confidentiality Disclaimer at the Bottom of an Email Legally Binding?

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iStock/Mlenny

For most of us, a day doesn’t go by without receiving a notice that “This email and attached documents may contain confidential information” and that you’re not authorized to read it if you aren’t the intended recipient. Anyone who has ever received one of these has probably wondered: How legally binding are these boilerplates?

The answer is: not very—though that’s not the entire story.

It’s generally agreed by legal experts that the generic boilerplate at the end of many emails has no legal weight behind it. It’s attempting to create a contract, but for a contract to apply both parties need to agree, which doesn’t happen in this case. At best it may make people paranoid about sharing your email and have an effect that way, although not necessarily through the power of law.

One case followed a doctor looking into suing his employer. Perhaps foolishly, the doctor emailed his lawyer from his work email, meaning that the employer felt that any confidentiality had been waived by use of the work email. The doctor disagreed and went to court. Part of the case was that every email sent by the law firm had the same standard disclaimer, but on that point the court ruled “[the law firm’s] pro forma notice at the end of the e-mail is insufficient and not a reasonable precaution to protect its clients.”

And their scope can be limited. One famous case seeking a protective order involved an extremely threatening email that included lines such as “Your most determined, unstoppable, and visceral enemy,” ending with "DISCLAIMER: Not one word herein should be construed by anyone as meaning violent or threatening intentions, and instead the entire contents is to be taken by the strict literary meaning. There have not been, and will be any elucidated threats of violence or intent, either expressed or implied, within the entirety of this document.” The court was unimpressed, granting the protective order and explaining "You can't send documentation of both a threatening and harassing manner and then think that you can get away with that by simply putting a disclaimer on it."

SHOULD I HAVE ONE?

This is not to say it’s useless to put a disclaimer on your emails, particularly with professional correspondence. In 2011 a lawsuit dealt in part with whether a customer list was a confidential trade secret. To maintain a trade secret, you need to take “reasonable efforts” to protect it. And the court determined that for a slew of reasons this customer list didn’t qualify as a trade secret. One of the issues brought up by the judge—though by no means the only one—was that the customer lists were sent to the other party on multiple occasions, and “The emails contain no disclaimer about the confidentiality of the materials attached.” That’s not to say the sending party would have been protected had they included the disclaimer, but the lack of one was a knock against them.

Disclaimers can also protect against contracts being formed. In one case, a real estate investor contacted a bank to inquire about some properties for sale. They signed a negotiation agreement acknowledging that email messages wouldn’t be considered binding. Over email he then made an offer, the bank made a counteroffer, and the investor agreed. The officer at the bank, however, had a disclaimer explaining that any price or term mentioned was not binding until the executive management committee signed off. Eventually the bank declined the agreement and the investor sued arguing breach of contract. The court ultimately ruled “in light of the e-mail disclaimers and the negotiation agreement [the investor] signed, any belief he had that his e-mailed acceptance of the counteroffer had created a binding contract was unreasonable.”

SO WHAT TO DO?

If you want to make your disclaimers count, and have a fighting chance in court if the situation arises, experts have a few suggestions. According to the law firm Reid & Hellyer, “To maximize the chances that such a disclaimer might be found effective, it may be better practice to place it at the beginning, not the end, of an email. However, if one were to do that for all e-mails sent, one might wonder if one really meant for the disclaimer to apply. It might be better practice to use disclaimers sparingly to certain particular emails only, not to every email sent.” But it’s probably best not to count on it to get you out of a jam.

*Disclaimer: this is not intended as a substitute for legal advice. Please consult a lawyer first!

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6 Factors That Determine Whether or Not You Remember Your Dreams

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iStock

Within the scientific community, dreams are still something of a mystery. Many experiments have been conducted and many theories have been put forth, but researchers still don’t fully understand why or how we dream. Further complicating matters is the fact that everyone dreams, but some people never remember their subconscious escapades.

However, improvements in brain imaging and recent physiological studies have brought us one step closer to answering the question of why some people remember their dreams more than others. There’s no simple, definitive explanation, “but there are a number of things that correlate,” Dr. Deirdre Leigh Barrett, a psychology professor at Harvard Medical School and author of The Committee of Sleep, tells Mental Floss. Barrett shared a few of the factors that can affect your dream recall.

1. SEX

Women, on average, recall more dreams than men. Researchers aren’t exactly sure why, but Barrett says it could be a biological or hormonal difference. Alternatively, women might be more cognizant of their dreams because they tend to be more interested in dreams in general. However, Barrett notes that differences between men and women in regard to dream recall are “modest” and that there are greater differences within each sex than between the sexes. In other words: There are plenty of women with low dream recall and plenty of men with high dream recall.

2. AGE

As we get older, it often gets harder to recall our dreams. Your ability to remember dreams improves in late childhood and adolescence, and tends to peak in your twenties, Barrett says. After that point, people often experience a gradual drop-off in dream recall. However, there are exceptions, and people sometimes experience the opposite.

3. PERSONALITY

Again, this is by no means a prescriptive rule, but there seems to be a correlation between certain personality traits and high dream recall. "More psychologically-minded people tend to have higher dream recall, and people who are more practical and externally focused tend to have lower recall," Barrett says. In addition, better dream recall has a “mild correlation” with better recall while completing certain memory tasks during waking hours, according to Barrett.

4. AMOUNT OF SLEEP

The amount of sleep one gets on average is one of the most important factors related to dream recall. People dream every 90 minutes during the REM (rapid eye movement) sleep cycle. However, those REM periods get longer throughout the night, meaning that you’re doing the most dreaming toward the morning—generally right before you wake up. If you only sleep four hours instead of eight, you’re only getting about 20 percent of your dream time. For this reason, some people report remembering more of their dreams on the weekend, when they have the chance to catch up on sleep.

5. BRAIN ACTIVITY

Thanks to brain imaging, scientists now have a better idea of which parts of the brain are associated with dreaming. A part of the brain that processes information and emotions is more active in people who remember their dreams more often, according to a 2014 study. This region toward the back of the brain, called the temporo-parietal junction (TPJ), may help people pay more attention to external stimuli. In turn, this may promote something called instrasleep wakefulness.

"This may explain why high dream recallers are more reactive to environmental stimuli, awaken more during sleep, and thus better encode dreams in memory than low dream recallers," Dr. Perrine Ruby told the International Business Times. "Indeed, the sleeping brain is not capable of memorizing new information; it needs to awaken to be able to do that."

Higher activity in the TPJ and another region of the brain called the medial prefrontal cortex (MPFC) might also "promote the mental imagery and/or memory encoding of dreams," researchers wrote in the study's abstract.

More recently, in 2017, researchers discovered that high dream recall is also linked to higher activity toward the front of the brain. The pre-frontal cortex is the part of the brain that deals with abstract thinking, so it makes sense that it has been linked to dream recall and lucid dreaming (being aware that one is dreaming), Barrett says.

6. RESPONSE TO EXTERNAL STIMULI

In a similar vein, people who remember their dreams more frequently also tend to exhibit more brain activity after hearing their name spoken aloud while they’re awake, according to a 2013 study. Upon hearing their names, a group of “high recallers,” who remember their dreams almost every night, experienced a greater decrease in a brain wave called the alpha wave than a group of “low recallers,” who remember their dreams once or twice a month. This decrease in alpha waves is likely preceded by an increase in brain activity upon hearing their names. Essentially, people with greater dream recall tend to experience activity in more regions of their brain in response to sounds. According to Barrett, there may be an evolutionary explanation for this.

“Evolution wants us to get restorative sleep but it also wanted us to wake up to danger and check it out and be able to go back to sleep quickly afterwards,” she says. Think of the all the dangers our prehistoric ancestors had to deal with, and it's clear that this response is important for survival. In essence, high recallers are “probably just a little more aware and watching during their dream, and that helps make it a long-term memory.”

So what can you do to help you remember your dreams? It may sound simple, but before you go to bed, think to yourself, “I’m going to remember my dreams tonight.” The very act of thinking about dreaming can make a big difference.

“You could say that just reading this article is somewhat more likely to make you recall a dream tonight,” Barrett says. “People who are taking a class on dreams or reading a book on dreams—any short-term intervention of paying more attention to them—tends to create a short-term blip in dream recall.”

When you first wake up, don’t do anything except lie in bed and try to recall any dreams you had. If something comes back to you, write it down or use a voice recorder to crystallize your thoughts. Dreams are still in your short-term memory when you wake up, so they’re fragile and easy to forget.

If you don’t remember anything, Barrett says it’s still helpful to assess how you feel when you first awaken. Are you happy, sad, or anxious? “Sometimes if you just stay with whatever emotion or little bit of content you woke up with,” she says, “a dream will come rushing back.”

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