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jtotheizzoe:

Message From the Moon

At first glance, these probably come across as little more than hastily painted watercolor sketches of the moon. That’s precisely what they are, actually. Attractive, yes, but certainly not high art.  

But hiding in their shadows lies a greater significance. The squiggled edges of that bleeding ink bear an observation that altered the heavens themselves. Or at the very least, our view of them.

The hand that traced these orbs belonged to none other than Galileo Galilei. They were included in his 1610 work Sidereus Nuncius (“The Sidereal Message”, which would make a great band name), the first scientific text based on telescope observations. To understand the significance of his illustrations, it helps to understand the world in which he drew them.

In 1610, cosmology, not that it had much to show for itself as a science, was still based on the ideas of Aristotle, who by this time had been dead for 18 centuries. So current! Copernicus’ observation that the Earth orbited the sun, first published in 1543, had begun to challenge Aristotelian supremacy, it wasn’t exactly a popular idea. 

Aristotle’s cosmological beliefs were based on the idea that the heavens were made of a perfect substance called “aether”, and therefore the circular motions and spherical shapes of heavenly bodies were also perfect. Earth, he claimed, was inherently imperfect, as were all the things that existed upon it. Everything in the heavens was awesome, and Earthly matter was inherently “just okay”, even if its name was Aristotle. This was one of the reasons people found Copernicus’ claims so hard to swallow. The imperfect Earth among the perfect heavens? Heresy!

Enter Galileo and his humble 20x telescope, in 1609. At the time, in Aristotelian fashion, the moon, being of the heavens, was assumed to be a perfect sphere, its dark and light areas just splotches upon the billiard-ball-smooth lunar surface. I imagine it took Galileo about 7 seconds of lunar observation to realize that was not the case.

The terminator, that line that separates the moon’s illuminated face from its dark one, is jagged as a crocodile’s smile. I’ve seen it myself through modern telescopes, and I must say, it’s really something to witness how light and shadow break over a distant crater’s edge. Galileo painted this in his sketches above, inferring that the moon in fact had a rough and crater-marked face. This meant that not only was Earth not the center of the universe, as Copernicus had shown, but the heavens themselves were imperfect, just like Earth.

Scientists would go on to realize that the orbits of heavenly bodies were not perfect circles, nor were the bodies perfect spheres, and that everything up there is made of the same stuff as everything down here. It was either a huge demotion for the heavens, or a great promotion for Earth, I’m not sure.

Galileo’s Sidereus Nuncius also included newly detailed maps of the constellations and the mention of four moons of Jupiter (although detailed observations of those were still centuries away), but it was his drawings of our moon that bore the most impact on future astronomical science, realigning the heavens with a single stroke of the brush.

Keep on drawing, and keep on looking up.

(You can read an English translation of Sidereus Nuncius here. If you’re hungry for more selenology, tour through these historical maps of the moon. Tip of the telescope to Steve Silberman for tweeting these sketches.)

currentsinbiology:

Quercetin alleviates high glucose-induced Schwann cell damage by autophagy


It is believed that hyperglycemia leads to increased aldose reductase activity and polyol metabolism in Schwann cells, and the resultant abnormal metabolites cause the organelle’s damage and morphological changes such as swelling and vacuolation. Autophagy can remove the damaged organelles, but also provide the materials for cell survival under stressful conditions. Quercetin can reverse high glucose-induced inhibition of neural cell proliferation. Quercetin is also implicated in the mechanism underlying the reduction of apoptosis through autophagy induction. Whether or not quercetin protects Schwann cells through autophagy pathways remains unclear. Dr. Ling Qu and co-workers from Peking Union Medical College Hospital, Peking Union Medical College, China Academy of Medical Sciences, China show that under high glucose conditions, there are fewer autophagosomes in immortalized rat RSC96 cells and primary rat Schwann cells than under control conditions, the proliferative activity of both cell types is signifcantly impaired, and the expression of Beclin-1 and LC3, the molecular markers for autophagy, is significantly lower. After intervention with quercetin, the autophagic and proliferative activity of both cell types is rescued. These results, published in the Neural Regeneration Research (Vol. 9, No. 12, 2014), suggest that quercetin can alleviate high glucose-induced damage to Schwann cells by autophagy.

Article: “Quercetin alleviates high glucose-induced Schwann cell damage by autophagy” by Ling Qu1, Xiaochun Liang1, Bei Gu2, Wei Liu1 (1 Department of Traditional Chinese Medicine, Peking Union Medical College Hospital, Peking Union Medical College, China Academy of Medical Sciences, Beijing, China; 2 Cell Center, Institute of Basic Medical Science, Peking Union Medical College, China Academy of Medical Sciences, Beijing, China) Qu L, Liang XC, Gu B, Liu W. Quercetin alleviates high glucose-induced Schwann cell damage by autophagy. Neural Regen Res. 2014;9(12):1195-1203.

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