The science news of the week: Your bed is not yours alone. When you crawl into a cozy bed at night, rest your head on an enticing pillow, and cover yourself with a blanket, you probably don’t think about who’s sharing the bed with you.
Meanwhile, according to Westminster University lecturer Manal Mohammed, a specialist in medical microbiology, your bed is simply a jungle teeming with unpleasant life forms. In fact (I advise those with weak nerves and disgust to skip the details), particles of sweat, saliva, dandruff, dead skin, and, frankly, food remnants summon whole hordes of bacteria, microbes, viruses, fungi, and even tiny insects to a festive banquet.
Let’s start with bacteria. When researchers selectively tested not only household beds, but also hospital beds, where nothing would seem to be able to thrive because hospitals are constantly disinfected, they found a variety of staphylococci, including the highly dangerous golden staphylococcus aureus. And although most of them do not pose a direct threat to humans, if they get into an open wound, they can cause a serious infection. In addition to staphylococci, intestinal Escherichia coli and other so-called gram-negative bacteria inhabit bedding. These bacteria are characterized by being enclosed in special capsules that protect them from leukocytes. In addition, many of them are highly resistant to antibiotics and can cause serious urinary tract infections, diarrhea, meningitis, pneumonia, and bloodstream infections.
But that’s not all. Every day you shed about 500 million dead skin cells. And this is a very appetizing snack for various microscopic mites. They are not dangerous themselves, but the products of their vital activity can cause all kinds of allergies and even asthma. We explain quickly, simply, and clearly what happened, why it matters, and what happens next. The number of episodes should remain the same. End of story.
Podcast advertising.
Well, of course, one cannot forget about such a fierce enemy of mankind as the bed bug. Although there is currently no conclusive evidence that these parasites are carriers of infection, their bites can be very painful and often lead to stress, insomnia, and various allergies. They can enter your home on clothing, in objects, books, or in any other way, and once they nest, they are extremely difficult to get rid of: you will most likely need to seek professional help.
“What do you do,” you ask, “when a whole menagerie is waiting for you in bed at home?” (The number of offers should remain) Manal Mohammed advises not to despair, but to simply make it a rule to do a few obligatory things before and after sleep. First, she recommends not making the bed immediately after sleeping, but rather throwing off the blankets and letting them dry, along with the sheets and pillows. It is also a good idea to open a window during this process. This will make your bed less attractive to microbes and small insects. Mattresses can also become attractive nesting places for various life forms, so it is better to vacuum them at least once a month and also cover them with a removable mattress cover that can always be washed. By the way, it is better to change the mattress periodically, and if it is already more than 10 years old, it is desirable to replace it with a new one: sometimes it is easier to get rid of the nest that microbes have woven than to evict them. Of course, all bed linen must be washed at least once a week at a temperature of 40-60°C (it used to be customary to boil it, but modern detergents make this unnecessary). Well, personal hygiene is also important: take a shower before going to bed, no snacks in bed, it’s better to remove makeup, creams and lotions before going to sleep, and there should be no room for pets in your bed either (yes, Manal admits that not everyone can refuse this, but imagine what they can do to themselves). And then you can really feel alone in bed.
The Mars rover Curiosity works tirelessly in Gale Crater, using its manipulators. According to a new study conducted by NASA (its results published in the journal Science), possible signs of ancient life on Mars have literally been erased from its surface.
This became clear when the Mars rover Curiosity began studying samples of sedimentary rocks in Gale Crater, which was formed by an asteroid impact about 3.6 billion years ago. For a long time, there was a huge lake in the crater, where the interaction of water and minerals should have formed significant reserves of clay, a key ingredient for life and, incidentally, an excellent material for preserving the fossilized forms of that life.
But when Curiosity retrieved two samples of ancient, 3.5-billion-year-old, clay-rich sedimentary rocks from the dried-up lakebed, it turned out that even though there was only 400 meters between the two rock collection points, one of the samples contained less than half the minerals typically found in clay. However, there was more than enough iron oxide to give the planet its red hue. Scientists say the culprit is brine, extremely salty water that has seeped into the mineral-rich clay layers and washed away all their geological and possibly biological history.
“We used to think that these layers of clay at the bottom of Gale Crater, once formed, remained unchanged for billions of years, preserving the geological memory of that time,” says Tom Bristow, project manager and NASA scientist at Ames Research Center in Mountain View, California. “But later, the brine dissolved the minerals in the clay, essentially resetting the geologic clock. Although the process of chemical transformation of sediments, known as diagenesis, and the removal of material from the surface of the planet preserves all possible signs of past life, the same process, according to scientists, could contribute to the formation of new life, but already deep below the surface.
“This is a very good place to look for signs of ancient life and, more generally, to determine the habitability of this planet,” said study co-author John Grotzinger, a professor of geology at the California Institute of Technology. “Although the signs of life in the ancient lake may have been erased during diagenesis, the components necessary to sustain life below the surface have emerged, making our discovery worthwhile.”
In February 2021, the “Perseverance” rover will join its “Curiosity” sibling, which has been working on Mars for nine years, greatly increasing the chances of finding signs of life. Meanwhile, the search has received a boost after astrogeologists calculated the possible locations of six methane emissions detected by the rover during its work in the crater. Because methane in the Earth’s atmosphere always has a biological source, scientists have high hopes that methane on Mars could be a sign of life.
Since the beginning of the coronavirus pandemic, many pet owners have been worried that their pets might be infected with this dangerous disease. Today, scientists can confidently say that many pets have indeed been infected, and it has been found that cats are more susceptible to COVID-19 than dogs. However, there is no need to panic.
After analyzing blood serum samples from 239 cats and 510 dogs taken between April and June 2020, the researchers found that 8% of the cats and less than one percent of the dogs actually had SARS-CoV-2, and the animals appeared to have been infected by their owners. “Since animals living under the same roof as us can be a source of various infections, it was very important for both our health and theirs to determine the extent to which the two most common types of pets are susceptible to COVID-19 and which type is more susceptible to infection,” says Hin Lee, author of the study (published in the journal Virulence) and professor of molecular biology at the University of Minnesota.
Scientists are quick to warn that although your cat is quite likely to contract COVID, it is unlikely to show any signs of illness and almost certainly will not transmit it to you. The same cannot be said for the owners themselves, who cuddle and kiss their pets, especially when they feel unwell and need emotional support.
As for why cats are more susceptible to coronavirus than dogs, researchers have yet to pinpoint the reason, but they suspect it has to do with the ACE2 protein, which serves as a receptor for the coronavirus. In cats, this protein is more similar to the human protein than in dogs.