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 ______    _    _    __   __   _    _    ______   
|      \\ | || | ||  \ \\/ // | || | || |      \\ 
|  --  // | || | ||   \   //  | || | || |  --  // 
|  --  \\ | \\_/ ||   / . \\  | \\_/ || |  --  \\ 
|______//  \____//   /_//\_\\  \____//  |______// 
`------`    `---`    `-`  --`   `---`   `------`

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Text this: Asymmetric transmission and optical low-pass filtering in a stack of random media with graded transport mean free path