• Investigation of stationary linear fractional differential equations as inpainting tools. • Physical motivation for introducing PDF inpainting tools and fractional generalizations. • Development of fast numerical algorithms for the inpainting problem. • Systematic comparison with the integer order equations.
For mass spectrometry-based diagnostics of microorganisms, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is currently routinely used to identify urinary tract pathogens. However, it requires a lengthy culture step for accurate pathogen identification, and is limited by a relatively small number of available species in peptide spectral libraries (≤3329). Here, we propose a method for pathogen identification that overcomes the above limitations, and utilizes the MALDI-TOF/TOF MS instrument. Tandem mass spectra of the analyzed peptides were obtained by chemically activated fragmentation, which allowed mass spectrometry analysis in negative and positive ion modes. Peptide sequences were elucidated de novo, and aligned with the non-redundant National Center for Biotechnology Information Reference Sequence Database (NCBInr). For data analysis, we developed a custom program package that predicted peptide sequences from the negative and positive MS/MS spectra. The main advantage of this method over a conventional MALDI-TOF MS peptide analysis is identification in less than 24 h without a cultivation step. Compared to the limited identification with peptide spectra libraries, the NCBI database derived from genome sequencing currently contains 20,917 bacterial species, and is constantly expanding. This paper presents an accurate method that is used to identify pathogens grown on agar plates, and those isolated directly from urine samples, with high accuracy.
Motivated by the successful printing of a computer-generated hologram using the computer-to-film (CtF) graphic process, we present a further refined technique with increased resolution, applicable in security. The CtF process offers low cost and fast production while persevering high resolution, and it can make every hologram unique. In this paper, we present the improvement of the printing method, with several software modifications and the implementation of security features at different levels of production.