RESUMO
Understanding the separation, concentration and purification processes of soft nanoparticles is essential for numerous applications in water filtration, bioprocessing and blood separation. Here we report unique translocation and rejection features of sub-micron sized microgels during frontal filtration using membranes having micron-sized porosity. Simultaneously measuring the increase in hydraulic resistance and electrical impedance change allows us to clearly distinguish two deposition phases: (a) microgel accumulation within the depth of the membrane porosity and (b) subsequent formation of a thin gel layer on the membrane surface. Such distinction is impossible using only classical hydraulic resistance analysis. The methodology only requires the ratio of microgel to solution conductivity as an input parameter.
RESUMO
Three-dimensional body scanners are attracting increasing interest in various application areas. To evaluate their accuracy, their 3D point clouds must be compared to a reference system by using a reference object. Since different scanning systems use different coordinate systems, an alignment is required for their evaluation. However, this process can result in translational and rotational misalignment. To understand the effects of alignment errors on the accuracy of measured circumferences of the human lower body, such misalignment is simulated in this paper and the resulting characteristic error patterns are analyzed. The results show that the total error consists of two components, namely translational and tilt. Linear correlations were found between the translational error (R2 = 0.90, 0.97) and the change in circumferences as well as between the tilt error (R2 = 0.55, 0.78) and the change in the body's mean outline. Finally, by systematic analysis of the error patterns, recommendations were derived and applied to 3D body scans of human subjects resulting in a reduction of error by 67% and 84%.
RESUMO
BACKGROUND: We tested the workflow and comparability of compression garments (CG) automatically knitted from 3D-body-scan data (3DBSD) versus manually measured data for scar treatment. Industry 4.0 has found its way into surgery, enhancing the trend toward personalized medicine, which plays an increasingly important role in CG scar therapy. Therefore, we conducted a study to evaluate the workflow from 3DBSD to fast and precisely knitted CG and compared it with standard of care. METHODS: A randomized controlled crossover feasibility study was conducted as part of the individual medical technology research project "Smart Scar Care." Objective and patient-reported outcome measures were documented for 10 patients with hypertrophic burn scars at baseline and after wearing CG automatically knitted from 3DBSD versus CG from manually measured data for one month. RESULTS: The "scan-to-knit" workflow and the study design were feasible in 10 of 10 patients. No adverse effects were found. 3DBSD showed a bias of half a centimeter compared with manually measured data and wider limits of agreement. With respect to fit, comfort, suitability, Vancouver Scar Scale, Patient and Observer Scar Assessment Scale, stiffness and microcirculation, this was a promising pilot study. Stiffness and blood flow were increased in scars compared with normal skin. The highest rank correlations were found between pain and itch, stiffness and Patient and Observer Scar Assessment Scale, Vancouver Scar Scale, and pain. CONCLUSIONS: These results indicate that automatically knitted CG using 3DBSD could become an alternative to the standard of care, especially with regard to economical and faster patient care. The produced scan data opens the door for objective scar science.