arXiv subjects

Petr Novák

Publications and source records attributed to Petr Novák.

4 recordsLinked to original sources

arXiv2026

Absorption mode broadband 2D MS for proteomics and metabolomics

Two-dimensional mass spectrometry (2D MS) is a method for tandem mass spectrometry that enables the correlation between precursor and fragment ions without the need for ion isolation. On a Fourier transform ion cyclotron resonance mass spectrometer, the phase correction functions for absorption mode data processing were found to be linear in the precursor ion dimension and quadratic in the fragment ion dimension. Absorption mode data processing on limited data sets has previously shown improvements in signal-to-noise ratio and resolving power by a factor of 2. Here, we have expanded absorption mode data processing to 2D mass spectra regardless of size and frequency range. We have applied absorption mode 2D MS to top-down analysis of variously oxidized ubiquitin proteoforms generated by fast photochemical oxidation of proteins (FPOP) and to an extract of ergot alkaloids. We show that absorption mode data processing significantly improves both the signal-to-noise ratio and the resolving power of the 2D mass spectrum compared to standard magnitude mode in terms of sequence coverage in top-down proteomics, as well as the accuracy of precursor-fragment correlation in metabolomics.

eess.SP↗

arXiv2025

The status quo of fire evacuation drills in nursery schools

Fire drills are a commonly-used training method for improving how people act in emergency situations. This article deals with fire drills in early childhood education facilities and analyses data gathered from an online survey of 1151 Czech nursery schools (23.5% of nursery schools invited to participate, 21.5% of all officially registered nursery schools in Czechia). It provides recommendations for improving the effectiveness of fire drills in nursery schools. Results suggest that regular (typically annual) fire drills are common training practices at these schools, but more frequent fire drills led to significantly fewer issues during evacuation. The most frequent evacuation issue encountered during fire drills, according to our data, was slow movement. Many children needed assistance, notably on stairs; nursery schools located only on the ground floor reported fewer issues during evacuation than other schools. The purpose, design, and implementation of fire drills with our study confirming results from prior studies must be properly integrated into complex and systematic fire safety education programs that specifically reflect the characteristics, needs, and possible limitations of preschool children.

physics.soc-ph↗

arXiv2019

Flexible Production Systems: Automated Generation of Operations Plans Based on ISA-95 and PDDL

Model-driven engineering (MDE) provides tools and methods for the manipulation of formal models. In this letter, we leverage MDE for the transformation of production system models into flat files that are understood by general purpose planning tools and that enable the computation of plans, i.e., sequences of production steps that are required to reach certain production goals. These plans are then merged back into the production system model, thus enriching the formalized production system knowledge.

eess.SY↗

arXiv2013

Shrinking annuli mechanism and stage-dependent rate capability of thin-layer graphite electrodes for lithium-ion batteries

The kinetic performance of graphite particles is difficult to deconvolute from half-cell experiments, where the influences of the working electrode porosity and the counter electrode contribute nonlinearly to the electrochemical re-sponse. Therefore, thin-layer electrodes of circa 1 μm thickness were prepared with standard, highly crystalline graphite particles to evaluate their rate capability. The performance was evaluated based on the different stage transitions. We found that the tran-sitions towards the dense stages 1 and 2 with LiC6 in-plane densi-ty are one of the main rate limitations for charge and discharge. But surprisingly, the transitions towards the dilute stages 2L, 3L, 4L, and 1L progress very fast and can even compensate for the initial diffusion limitations of the dense stage transitions during discharge. We show the existence of a substantial difference between the diffusion coefficients of the liquid-like stages and the dense stages. We also demonstrate that graphite can be charged at a rate of ~6C (10 min) and discharged at 600C (6 s) while maintaining 80 % of the total specific charge for particles of 3.3 μm median diameter. Based on these findings, we propose a shrinking annuli mechanism which describes the propagation of the different stages in the particle at medium and high rates. Besides the limited applicable overpotential during charge, this mechanism can explain the long-known but as yet unexplained asymmetry between the charge and discharge rate performance of lithium intercalation in graphite.

cond-mat.mtrl-sci↗