Ice Spike
An ice spike is an upward-facing icicle that forms as a body of water freezes. Ice spikes can form in natural environments or can be made artificially by freezing distilled water in plastic ice cube trays.
Water expands when it freezes. If there already is a thin sheet of surface ice over the body of water, further freezing can force water out and upwards through a crack or weak point in the sheet. This can produce a tube-like structure where water emerges at the tip, progressively lengthening the tube. Tube formation stops when the tip freezes and seals.
Ice spikes rarely form when freezing “normal” non-distilled water because impurities in the water act as an ice nucleus so the water freezes before an ice spike can form.
The formation of ice spikes is related to the shape of the water body, the concentration of dissolved impurities, air temperature and air circulation above the water.
chips electrical-engineering electronics ibm link transistors video
by Layne
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Picosecond imaging circuit analysis
Picosecond imaging circuit analysis (PICA) is a very cool method for measuring the activity of transistors in a CMOS integrated circuit. See [1] for details, but the basic idea is this: When a CMOS transistor switches state, it has a small probability of emitting an infrared (IR) photon. Since silicon is transparent to light with a wavelength longer than 1 micron, the IR photons can pass right through the silicon base of the chip. Researchers at IBM and elsewhere are setting up high-speed IR photodetectors to record these photons over many clock cycles, and produce very cool, visual records of which transistors are firing, and when in the clock cycle they are firing. As noted before, generation of an IR photon is not guaranteed, so the following movie was created from the records of a large number of clock cycles.
In this movie, the chip being tested has a distributed and hierarchical clock distribution network. This means that the initial clock buffered and amplified by a tree of buffers. As you can see in the video linked below, there is an initial pair of flashes near the top, followed by a large flash near the center, then a handful of distributed flashes, after which the chip lights up as all of the individual gates switch. Very cool stuff.
Here is a screenshot from the original source video at [2]:
Steagles
The “Steagles” is the popular nickname for the team created by the temporary merger of two National Football League NFL teams, the Pittsburgh Steelers and the Philadelphia Eagles, during the 1943 season. The teams were forced to merge because both had lost many players to military service due to World War II.
Officially the team was known simply as the Eagles without a city designation, the Eagles-Steelers, or the Steelers-Eagles. The NFL never registered “Steagles” as a trademark. However, the official NFL record book refers to the team as “Phil-Pitt.”
Honeycrisp Apples
But the Honeycrisp, developed in 1991 by two researchers at the University of Minnesota, really is kind of amazing: firm, wonderfully flavorful, tart and sweet at the same time. It’s no wonder that they often sell for twice as much as other apples and that growers sound like used-car dealers when they talk about them.
“I’ve been doing this for 30 years, and there’s nothing that’s come close to this,” said Tre Green of Chazy Orchards in Chazy, N.Y. He was one of the first people in the state to try them and now has them on about 80 of his 800 acres. “It’s a hard apple to grow, but it has such a spectacular taste, I think supply is going to take a long, long time, if ever, to catch up with demand.”
And if nothing in his experience selling apples is comparable, how about in other businesses? He paused: “Well, maybe the development of the Internet for information exchange.”
From the comments:
I think of Honeycrisps as being sort of like the Blue Moons of the apple world. Mass market, not as good as the real artisanal stuff, but about a thousand times better than the red delicious/Coors options. So while I prefer to buy a box of just-in-season artisanal apples, at the grocery store I’m happy to buy a Honeycrisps rather than the depressing other choices.