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What Makes Sulfur Smell So Bad?

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If you’ve ever caught a whiff of natural gas, you know the stench is similar to that of bad eggs or rotting cabbage. But the unsavory smell also saves lives: Gas leaks put our homes at risk for fires and explosions, and can even cause asphyxiation and death. Since pure natural gas (a.k.a. methane) has no smell, utility companies add smelly, sulfur-containing odorants called mercaptans, or thiols, to warn us if anything is amiss with our pipelines.

In fact, scientists say that our ability to discern even miniscule levels of volatile sulfur compounds is key to human survival in general, as it helps us detect rotten food, atmospheres with low oxygen levels, and even the urine of potential predators. That’s why chemists and neurobiologists from the University at Albany set out to find which of the nose’s olfactory receptors are responsible for their stench, along with factors that affect our sensitivity to it. Their results were recently published in the Journal of the American Chemical Society.

Olfactory receptors are present in specialized sensory cells called olfactory sensory neurons, which line our noses. They’re responsible for detecting molecules in our surroundings and sending messages to our brain so that we can recognize and label a smell. Chemistry professor Eric Block and other researchers from the Shanghai Institutes for Biological Sciences, Duke University, Yale University, and the National Institute of Standards and Technology located the receptor—known as OR2T11—that’s most responsive to thiols.

The researchers also found that the presence of copper ions in our nose’s mucus greatly amplifies our sensitivity to them. “Using molecular dynamics simulations, the team found two binding sites which contained copper,” Chemistry World explained. “The importance of both sites in detecting thiols was confirmed by site-directed mutagenesis: genetically engineered receptors lacking the amino acids responsible for copper binding lost all functionality.”

“Obviously it is essential for everyone to be able to detect gas leaks by recognizing the smell of the sulfur odorant,” Block said in a release. “Unfortunately, some people have a diminished sense of smell, or the absence of smell all together. Understanding how we smell sulfur could help doctors treat those who are not responsive it.”

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What’s the Difference Between Prison and Jail?
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Many people use the terms jail and prison interchangeably, and while both terms refer to areas where people are held, there's a substantial difference between the two methods of incarceration. Where a person who is accused of a crime is held, and for how long, is a factor in determining the difference between the two—and whether a person is held in a jail or a prison is largely determined by the severity of the crime they have committed.

A jail (or, for our British friends, a gaol) refers to a small, temporary holding facility—run by local governments and supervised by county sheriff departments—that is designed to detain recently arrested people who have committed a minor offense or misdemeanor. A person can also be held in jail for an extended period of time if the sentence for their offense is less than a year. There are currently 3163 local jail facilities in the United States.

A jail is different from the similarly temporary “lockup”—sort of like “pre-jail”—which is located in local police departments and holds offenders unable to post bail, people arrested for public drunkenness who are kept until they are sober, or, most importantly, offenders waiting to be processed into the jail system.

A prison, on the other hand, is usually a large state- or federal-run facility meant to house people convicted of a serious crime or felony, and whose sentences for those crimes surpass 365 days. A prison could also be called a “penitentiary,” among other names.

To be put in a state prison, a person must be convicted of breaking a state law. To be put in a federal prison, a person must be convicted of breaking federal law. Basic amenities in a prison are more extensive than in a jail because, obviously, an inmate is likely to spend more than a year of his or her life confined inside a prison. As of 2012, there were 4575 operating prisons in the U.S.—the most in the world. The country with the second highest number of operating prisons is Russia, which has just 1029 facilities.

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What Do Morticians Do With the Blood They Take Out of Dead Bodies?
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Zoe-Anne Barcellos:

The blood goes down the sink drain, into the sewer system.

I am not a mortician, but I work for a medical examiner/coroner. During an autopsy, most blood is drained from the decedent. This is not on purpose, but a result of gravity. Later a mortician may or may not embalm, depending on the wishes of the family.

Autopsies are done on a table that has a drain at one end; this drain is placed over a sink—a regular sink, with a garbage disposal in it. The blood and bodily fluids just drain down the table, into the sink, and down the drain. This goes into the sewer, like every other sink and toilet, and (usually) goes to a water treatment plant.

You may be thinking that this is biohazardous waste and needs to be treated differently. [If] we can’t put oil, or chemicals (like formalin) down the drains due to regulations, why is blood not treated similarly? I would assume because it is effectively handled by the water treatment plants. If it wasn’t, I am sure the regulations would be changed.

Now any items that are soiled with blood—those cannot be thrown away in the regular trash. Most clothing worn by the decedent is either retained for evidence or released with the decedent to the funeral home—even if they were bloody.

But any gauze, medical tubing, papers, etc. that have blood or bodily fluids on them must be thrown away into a biohazardous trash. These are lined with bright red trash liners, and these are placed in a specially marked box and taped closed. These boxes are stacked up in the garage until they are picked up by a specialty garbage company. I am not sure, but I am pretty sure they are incinerated.

Additionally anything sharp or pointy—like needles, scalpels, etc.—must go into a rigid “sharps” container. When they are 2/3 full we just toss these into one of the biotrash containers.

The biotrash is treated differently, as, if it went to a landfill, then the blood (and therefore the bloodborne pathogens like Hepatitis and HIV) could be exposed to people or animals. Rain could wash it into untreated water systems.

This post originally appeared on Quora. Click here to view.

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