FindFoci: a focus detection algorithm with automated parameter training that closely matches human assignments, reduces human inconsistencies and increases speed of analysis

Accurate and reproducible quantification of the accumulation of proteins into foci in cells is essential for data interpretation and for biological inferences. To improve reproducibility, much emphasis has been placed on the preparation of samples, but less attention has been given to reporting and standardizing the quantification of foci. The current standard to quantitate foci in open-source software is to manually determine a range of parameters based on the outcome of one or a few representative images and then apply the parameter combination to the analysis of a larger dataset. Here, we demonstrate the power and utility of using machine learning to train a new algorithm (FindFoci) to determine optimal parameters. FindFoci closely matches human assignments and allows rapid automated exploration of parameter space. Thus, individuals can train the algorithm to mirror their own assignments and then automate focus counting using the same parameters across a large number of images. Using the training algorithm to match human assignments of foci, we demonstrate that applying an optimal parameter combination from a single image is not broadly applicable to analysis of other images scored by the same experimenter or by other experimenters. Our analysis thus reveals wide variation in human assignment of foci and their quantification. To overcome this, we developed training on multiple images, which reduces the inconsistency of using a single or a few images to set parameters for focus detection. FindFoci is provided as an open-source plugin for ImageJ

Synthesis and Characterization of Thermal Properties of Type Eu2O3-ZrO2 Sinters

The oxides with pyrochlore or defected fluorite structure are a potential alternative ceramic materials for now widely used yttria-stabilized zirconia 8YSZ in the application for the insulation layer of thermal barrier coatings systems. This paper presents a procedure of synthesis of europium zirconate of Eu2Zr2O7 type, by the method of high temperature sintering under pressure. The analysis of the effect of the powders` homogenization methods on homogeneity of final sintered material showed that the highest homogeneity can be obtained after mechanical mixing in alcohol. Moreover, the DSC investigation carried out on a mixture of powders before the sintering process and on the material after high temperature sintering under pressure, suggest the synthesis of a new phase an europium zirconate Eu2Zr2O7 with the pyrochlore structure. Obtained phase was characterized by stability over the entire range of tested temperature, i.e. to 1450°C. The resulting material based on europium zirconate has a lower coefficient of thermal diffusivity than the now widely used 8YSZ

Synthesis and Characterization of Thermal Properties of Type Eu2O3-ZrO2 Sinters

The oxides with pyrochlore or defected fluorite structure are a potential alternative ceramic materials for now widely used yttria-stabilized zirconia 8YSZ in the application for the insulation layer of thermal barrier coatings systems. This paper presents a procedure of synthesis of europium zirconate of Eu2Zr2O7 type, by the method of high temperature sintering under pressure. The analysis of the effect of the powders` homogenization methods on homogeneity of final sintered material showed that the highest homogeneity can be obtained after mechanical mixing in alcohol. Moreover, the DSC investigation carried out on a mixture of powders before the sintering process and on the material after high temperature sintering under pressure, suggest the synthesis of a new phase an europium zirconate Eu2Zr2O7 with the pyrochlore structure. Obtained phase was characterized by stability over the entire range of tested temperature, i.e. to 1450°C. The resulting material based on europium zirconate has a lower coefficient of thermal diffusivity than the now widely used 8YSZ

XRD study of Eu₂O₃-ZrO₂ feedstock powders and sintered materials

Presented article described synthesis process of nonstoichiometric europium zirconate by solid state reaction between weight-equal mixture of ZrO₂ and Eu₂O₃ feedstock powders. To final material synthesis high temperature vacuum press was used as well as a free standing process of sintering. As a result europium zirconates were obtained. X-ray diffraction characterization revealed that relatively homogeneous materials were synthesised but scanning electron microscopy analysis showed many areas with nonhomogeneous composition. On the base of X-ray diffraction patterns, characterization of crystallite size as well as a lattice strain were calculated. The Williamson-Hall, Halder-Wagner and Cauchy-Gauss methods were used to make the calculations. Obtained data showed that there was no significant differences between crystallite size with zirconate materials obtained by solid state reaction at temperature 1350°C in vacuum press and by free standing process. The short heating at higher temperature (1450°C/5 h) has no influence on crystallite size as well, but 24 h of additional heating strongly increases the crystallite size