RegEx change chars case

pattern	info	example
`\U`	uppercase	`ABC DEF GHI`
`\L`	lowercase	`abc def ghi`
`\I`	initial capitals	`Abc Def Ghi`
`\F`	first capital	`Abc def ghi`
`\E`	exit case changes
`\Xn`	apply to reference	`\U1` = `\U\1\E`

Source: Replacement Text Case Conversion