Summarize the following:
A diode is composed of an N-type semiconductor joined with a P-type semiconductor. The N-type semiconductor is the negative end of the diode and is called the "cathode". The P-type semiconductor is the positive end of the diode, and is called the "anode".  If the positive side of a voltage source is connected to the positive end of the diode (the anode), and the negative side is connected to the negative end of the diode (the cathode), the diode will conduct current. If the diode is reversed, the current is blocked (up to a limit). Diodes are indicated on schematics by a symbol (—▷|—) that shows how the diode should be installed. An arrow points at a vertical bar, which has a line continuing out of it. The arrow indicates the positive side of the diode, while the vertical bar indicates the negative side. You can think of it as the positive side flowing into the negative side, with the arrow indicating the direction of the flow. If the diode doesn't have the schematic symbol printed on it, look for the ring, band, or line printed on the diode. Most diodes will have a large colored band printed near the negative side (cathode) of the diode. The band will go all the way around the diode. An LED is a light-emitting diode, and you can usually tell which side is positive by examining the legs. The longer leg is the positive, anode pin. If the pins have been trimmed, examine the outer casing of the LED. The pin nearest to the flat edge is the negative, cathode pin.

summary: Understand how a diode functions. Learn what the diode schematic symbol means. Look for the large band. Identify the positive end of an LED.


Summarize the following:
Put a few inches of water in the bottom of a large pot. You only need enough to create steam to wilt your arugula. To give your arugula a bit more flavor, add a pinch of salt to the pot of water. Place the pot of salted water on a stovetop burner and heat it to boiling. Then, turn the heat down so the water bubbles gently. If you don’t have a steamer, you can rest a metal colander or strainer inside the pot, making sure the boiling water doesn’t touch it. Use as much arugula as you think you will need. Cover the pot to trap the steam inside. Allow the arugula to steam for a few minutes, or until wilted to your liking. Then, carefully remove the steamer from the pot of water and serve the arugula.

summary: Put salted water in a pot. Heat the water to boiling. Place arugula in a vegetable steamer over the boiling water. Wilt the arugula for 2-3 minutes over the water.


Summarize the following:
A “medical alert” tattoo is a tattoo that communicates important medical information about a patient, such as a severe allergy or the presence of a disease. These tattoos are meant to replace traditional medical alert bracelets, which can get lost. Although these tattoos are growing in popularity, there is still no consensus about the design or placement of such tattoos. This can make them more difficult for medical professionals to detect. A “meat tag” is a tattoo on a member of the US military, meant to indicate essential identification data. These tattoos—which perform the same function and often mimic the appearance of traditional “dog tags”—are growing in popularity within the armed forces. External radiotherapy (sometimes called external beam radiotherapy) is a form of cancer treatment that uses a machine to aim beams of radiation at cancer cells. A series of marks must be made on the patient’s skin—either small tattoos or dots of permanent marker—to guide the radiotherapy process. Radiotherapy tattoos are preferable to marks made by permanent marker because they cannot be accidentally washed off.  Unlike other medical tattoos, you may have this done directly by your radiographer. If you prefer to have these tattoos done at a studio, your radiographer can draw marks for your tattoo artist to follow. Following breast surgery (usually a mastectomy, but sometimes also breast reductions) many patients opt to have tattoos done. These may be cosmetic—tattooing on an areola or replacing lost pigment—or aesthetic—an elaborate design to cover scars and/or signify one’s journey. Sometimes women opt to have a post-mastectomy tattoo instead of breast implants or other cosmetic surgery. Other times, these tattoos are in addition to cosmetic reconstruction.
summary: Learn about “medical alert” tattoos. Research “meat tag” tattoos. Learn about “radiotherapy” tattoos. Look into “post-mastectomy” tattoos.