Ring-shaped segmentation phase design method for the combined point spread function.

The study presents a method for designing phase masks, specifically the ring-shaped segmentation method, which can be employed in creating the modulation phase for specialized point spread functions (PSFs), such as multi-focus PSFs and those with axial encoding functions. An algorithm for phase inversion optimization is introduced to enhance the optical transfer function efficiency of the designed phase mask, which is based on the Fresnel approximation imaging inverse operation and iterative Fourier transform algorithm. The ring-shaped segmentation phase design approach effectively combines individual phases, resulting in unified PSFs with unique properties.

Development of ankylosing spondylitis in patients with ulcerative colitis: A systematic meta-analysis.

Background: Ulcerative colitis (UC) is a manifestation of inflammatory bowel disease (IBD), which can cause inflammation of the intestinal tract. Ankylosing spondylitis (AS) is an inflammatory disease of the sacroiliac joints. Many studies have found that some UC patients progress to AS.