By WWII, scientists had already begun looking at alternative gelling substances for routine use in bacteriology, but concluded that agar was still better as it is both firmer and easier to handle. Today, some specialized microbiology applications use the colloid carrageenan (extracted from red seaweed Chondrus crispus, or “Irish Moss”), a more transparent and less auto-fluorescent alternative to agar (agar emits its own background fluorescence when excited by light). However, for routine bacteriological use, carrageenan is more difficult to dissolve, requires higher concentrations, can degrade at high temperatures, and forms weaker gels, which may result in puncturing its surface during the plating of cells.
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Some ergonomic keyboards come with permanent or removable wrist or palm rests, which can be cushioned or hard. This is another area where opinions diverge: proponents claim they help you maintain a neutral hand position, while detractors say they put pressure on the tendons and can cause wrist pain or even exacerbate conditions like carpal tunnel. Ideally, your palms should be resting, not your wrists, and you might find you like having that support or you may find the pressure uncomfortable.