No abstract

Tang D.-S., Tian Y.-J., He Y.-Z., Li L., Hu S.-Q., Li B. (2010): Optimisation of ultrasonic-assisted protein extraction from brewer's spent grain. Czech J. Food Sci., 28: 9-17, Response surface methodology was employed to optimise the ultrasonic-assisted extraction of protein from brewer's spent grain. Three variables, namely the extraction time (min), ultrasonic power (W/100 ml of extractant), and solid-liquid ratio (g/100 ml) were investigated. Optimal conditions were determined and tri-dimensional response surfaces were plotted using mathematical models. The ANOVA analysis indicated that all the quantities determined, i.e. the extraction time, ultrasonic power, and solid-liquid ratio, had significant positive linear and negative quadratic effects on the protein yield. Optimum conditions for the extraction of protein were found to be: the extraction time of 81.4 min, ultrasonic power of 88.2 W/100 ml of extractant, and solid-liquid ratio of 2.0 g/100 ml. The optimal predicted protein yield obtained was 104.2 mg/g BSG while the experimental yield of protein was in agreement with the predicted value.

Cooperative controls of magnetic microswimmers are desired for complex micromanipulation and microassembly tasks. Self-assembled magnetic micropaddles as microswimmers that can locomote freely and cooperate at liquid surfaces are proposed inspired by the paddling motion. The micropaddles are self-assembled with metallic disks under a rotating magnetic field, and they are endowed with controlled propulsion in the precessing field. The micropaddles can locomote freely with a maximum speed of approximately 3.3 mm/s and manipulate objects at the liquid surface. It is found that the micropaddles reverse moving directions at high frequencies and that those with different lengths can locomote in opposite directions under the same precessing magnetic field. Based on the distinctive motion properties, not only could several micropaddles combine into the longer ones but a single micropaddle could also be disassembled into two cooperative partners. Assemblies of different parts based on their cooperation are realized in this study, which is challenging for other types of magnetic microswimmers. Micropaddles with adjustable length, flexible locomotion, and cooperative capability present a promising avenue for various micromanipulation applications.

Microrobots have attracted considerable attention due to their immense potential for biomedical and engineering applications in recent years. Inspired by human walks, a bipedal microwalker capable of standing and walking...