Some organisms, such as the castor bean plant (Ricinus communis), produce substances that inhibit the synthesis of proteins (called translation) within a cell. (The plant, which is native to Africa, is not related to the species of bean plants with which you are likely more familiar.) A protein called ricin, produced within the castor seeds is an extremely potent inhibitor of protein synthesis. In fact, it is one of the strongest natural toxins produced. A single chewed seed can kill child! If the ricin were purified, it would take an amount equivalent to only a few grains of salt to kill an adult. Ricin kills cells by enzymatically cleaving covalent bonds within the large and small ribosomal subunits, rendering the protein-building factori [ ... ]
The cube shown above, known as the element cube, combines every 'collectible' element on Earth. Regarded by its creator as the world’s largest alloy, the cube is fashioned into a minimalist decorative ornament that could sit on your desk or coffee table! It consists of 62 elements (shown below) and measures 5 cm by 5 cm; it ships with a material analysis report - that presumably indicates what percentage of each metal is contained in the alloy - and offers custom engraving as an extra option.
Shallow waters will sometimes get too hot, forcing one fish to make a break for the shore. The tiny mangrove rivulus (shown above) avoids neurological damage from hot swamps by escaping to land. Retreating to land allows the fish to cool down through a process called evaporative cooling, which is akin to human sweating but using water from the environment. Previously, scientists had suggested that the fish, besides simply escaping hot water, might be taking advantage of evaporative cooling.
Isn't it strange, two FDA-approved drugs - topical ruxolitinib or tofacitinib - can reawaken dormant hair follicles! According to the study, within 3 weeks, mice that received topical ruxolitinib or tofacitinib had regrown nearly all their hair (right photo; drug was applied only to the right side of the mouse). Little to no hair growth occurred in control mice during the same timeframe (left photo). According to researchers at Columbia University Medical Center, inhibiting a family of enzymes inside hair follicles that are suspended in a resting state restores hair growth.
These drugs, known as JAK inhibitors have been approved to treat blood diseases (ruxolitinib) and the other for rheumatoid arthritis (tofacitinib). Both are being tested [ ... ]
Meet the cassowary. These are flightless birds native to the tropical forests of New Guinea and northeastern Australia. There are three extant species. The most common of these, the southern cassowary, is the third tallest and second heaviest living bird, smaller only than the ostrich and emu.
All three species have horn-like but soft and spongy crests called casques on their heads, up to 18 cm (7 inches), which serves several purposes. The most interesting being that the wedge-shaped casque may have evolved to protect the head of this animal by deflecting falling fruit, since cassowaries spend a lot of time under trees where seeds the size of golfballs or larger fall from heights of up to 30 metres! [ ... ]
In the Tian Shan Mountains of China, researchers have spotted the elusive Ili Pika, an adorable creature which hasn’t been seen in two decades.
The so-called "magic bunny" measures about eight inches long and is a distant relative of the rabbit. It has eluded research teams for decades, sneaking in and out of cliffs. Around the time of its discovery, back in 1983, the species numbered around 2900. Now, their numbers are down to less than a thousand, most likely due to human activity and climate change. [ ... ]
Pangolins, often called "scaly anteaters," are solitary, primarily nocturnal animals, are easily recognized by their full armor of scales. If that's not impressive enough, their tongues are attached near its pelvis and last pair of ribs, and when fully extended is longer than the animal’s head and body. At rest a pangolin’s tongue retracts into a sheath in its chest cavity.
Could the most widely used personality questionnaire simply be a farce?
In case you don't know, the Myers-Briggs test is an assessment test believed by many to measure psychological preferences in how they perceive things and help them in making decisions. According to the Myers-Briggs test, there exist sixteen different types of personalities. This Myers Briggs Test has a series of questions that require your answers, which in turn determine the type of personality you have and provides you with general assumptions concerning how your personality type best suits you.
Back in year-3 of my undergrad., I had to spend $20 to take the test for an assignment I had to write. While it was interesting to note how my personality could be read throug [ ... ]
NASA’s Cassini spacecraft completed the first of three final flybys of Saturn’s icy moon, Enceladus. On October 14, Cassini passed within 1838 kilometers (1142 miles) of Enceladus, providing unprecedented views of the moon’s north polar region. What's more, researchers predict that is contains a global ocean lying beneath its icy crust. Researchers found the magnitude of the moon's very slight wobble, as it orbits Saturn, can only be accounted for if its outer ice shell is not frozen solid to its interior, meaning a global ocean must be present.
It's true, the adder's-tongue ferns (Ophioglossum) pictured above has the highest chromosome count of any known living organism, with 1,262 chromosomes. In comparison, most species have far fewer chromosomes (i.e. humans have 46, 23 pairs). However, the number of chromosomes doesn't suggest that this species is more complex - after all, it's a plant! Some organisms, like this plants can self-fertilize, therefore they end with extra chromosomes. Over many generations, these chromosomes accumulate, hence the large number found in Ophioglossum. [ ... ]
The long-lasting search and debate around the size and identity of the world's smallest free-living insect seems to have now ended with the precise measurement and second record of the featherwing beetle species (Scydosella musawasensis). Described in 1999, representatives of this minute beetle have recently been retrieved once again from fungus in Colombia. The smallest individual measured the astounding 0.325 mm.
When homing pigeons fly home they rely on smells, magnetic fields, and vision to guide their way. But how important visual memory is for pigeons has long remained a mystery. According to a new study, pigeons that learned their way home with a blocked left eye couldn’t repeat the same journey when they wore a patch over their right eye, and vice versa. Instead, they flew slightly off course, following more of a curve than a straight line. Since birds lack a corpus callosum, this suggests that a birds’ lack of this key neural structure greatly affects how pigeons are able to find their way home.
Having more cells usually puts one at a higher risk for cancer - but not for the elephant. Despite packing 100 times as many cells as humans, this towering animal can keep cancer at bay thanks to extra copies of a tumor-fighting gene. Researchers found that Asian elephants harbor 30 to 40 copies of the gene that encodes the protein p53, one of the most important mechanisms for preventing cancer and maintaining cell division. If cells have DNA damage that could spawn tumors, p53 prevents them from dividing until they make repairs or spurs them to commit suicide. In contrast, humans sport only two copies of the gene for p53, and so does elephants’ closest living relative, the rock hyrax. The extra copies probably accumulated millions of yea [ ... ]
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