Flipping Magnetic Fields

North and south. We take these directions for granted. Pull out a compass and the needle will swing to the north in response to the magnetism in the Earth's crust. The magnetic poles roughly coincide with the axis of the Earth's rotation. But some scientists believe that the Earth's magnetic field has reversed itself several times within geological ...

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What Is Polarimetry?

Polarimetry is the technique of measuring the 'polarization' of light. Most of the light we encounter every day is a chaotic mixture of light waves vibrating in all directions. Such a combination is ... Continue reading


The Equivalence Principle

Four hundred years ago--or so the story goes--Galileo Galilei started dropping things off the Leaning Tower of Pisa: Cannon balls, musket balls, gold, silver and wood. He might have expected the ... Continue reading


Eratosthenes Measured Earth’s Circumference—Centuries Before Columbus Sailed

Eratosthenes (c. 276 – 194 BC) was born more than 2200 years ago in the Greek city of Cyrene, now a city in the North African country of Libya. (The Greek Empire surrounded much of the Mediterranean ... Continue reading


Liquid Crystal Communication

The Information Age rides on beams of carefully controlled light. Because lasers form the arteries of modern communications networks, dexterous manipulation of light underpins the two definitive ... Continue reading


The Human Pancreas

HumanPancreasThe pancreas is a body organ that does some heavy lifting. It carries on two important functions relating to digestion and the regulation of blood sugar. The exocrine, the larger function, makes enzymes to help digest food such as proteins and fats. The exocrine portion releases these enzymes into the pancreas duct where it flows into the duodenum and mixes with food after it has left the stomach.

The other function of the pancreas is called endocrine. It consists of scattered cells called islet cells which make hormones such as insulin and glucagon which regulate the body's blood sugar and hold it within a very tight range. If your blood sugar is too low, your brain won't function properly. If it is too high you would have diabetes which leads to damage to various body parts.

The pancreas is about the size of a small oblong loaf of bread. In humans, it is located in the back of the abdomen, behind the stomach and intestines, just above the belly button and against the spine. If affected by disease, the pancreas does not regenerate itself. If you lose more than 90% of your islet cells, you end up with diabetes. If you have chronic pancreatitis, an inflammation of the pancreas, you will have trouble with digestion and have to take enzyme pills. The pancreas works hard to process the food we eat.