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James Clark Edgerton

James Clark Edgerton was a U. S. Army aviator and Air Mail pilot who as a young lieutenant flew the Philadelphia to Washington, D. C. leg on the first day of scheduled Air Mail service in the United States on May 15, 1918. Edgerton, who retired as a colonel, was credited with being the first pilot to fly into a thunderstorm and with devising the first fire-extinguishing system installed for an aircraft engine, he helped to organize a civilian pilot-training program and during World War II he served as executive officer for air operations of the War Department. During his first Air Mail flight from Philadelphia to Washington Lt. Edgerton flew into a thunderstorm at 10,000 feet. "One instant the airplane became a tremendous elevator, leaping skyward hundreds of feet," Edgerton noted after landing at the Polo Grounds in Washington, "then the bottom promptly falls out, dizzy fall of hundreds of feet. I was attacked by solid waves of air."Edgerton flew 52 trips over a total of 7,155 miles, spending 107 hours in the air and making only one forced landing as an Army Air Mail pilot.

When the Post Office Department took over flying operations of the Air Mail Service in 1918, Edgerton stayed with the service becoming the Superintendent of Flying Operations. He organized and became superintendent of the Radio Service of the Post Office Department establishing its first aeronautical radio stations

Uup RNA motif

The uup RNA motif is a conserved RNA structure, discovered by bioinformatics.uup motif RNAs are found in Firmicutes and Gammaproteobacteria. Uup motif RNAs function as cis-regulatory elements, in view of their positions upstream of protein-coding genes. Uup RNAs are found upstream of genes encoding an ATPase; the precise role of these ATPases is not known, but they are predicted to either function as part of an ATP-binding cassette transporter or as fungal elongation factor 3. In some cases, the ATPase genes downstream of uup RNAs seem to be transcribed as part of a larger operon. In a handful of these cases, one of the operon's genes encodes the DUF2992 conserved protein domain; this gene is, in turn, regulated by the yjdF RNA motif, which might function to sense azaaromatic compounds.uup RNAs are located 100 nucleotides upstream of predicted Rho-independent transcription terminators. Since these transcription terminators are located somewhat far away, it is not clear that they are functionally related.

If uup RNAs do function as cis-regulatory elements, they might inhibit the formation of the transcription terminator's secondary structure in order to control the expression of the downstream gene. The hypothesis that uup RNAs correspond to riboswitches has been considered; these RNAs exhibit several conserved nucleotide positions, despite a wide distribution in two bacteria phyla. However, the secondary structure of these RNAs was considered unusually simple compared to most known riboswitch structures