Anomalous Hall effect is a time-reversal symmetry breaking electronic response discovered in ferromagnets in the 19th century and continuing to play a key role in modern fields of physics and nanoelectronics. In contrast, the antiparallel magnetic order on common rutile crystals served as a classic example which kept compensated magnets for nearly a century outside the focus of the magneto-electronic research. Breaking with this traditional perception, the antiparallel magnetic order on the rutile crystal of RuO 2 has been predicted to generate anomalous Hall effect of comparable strength to ferromagnets. Here we report the experimental demonstration of the anomalous Hall effect in RuO 2 . We show that the effect arising from the antiparallel magnetic order dominates over an ordinary Hall contribution, and a contribution due to a weak field-induced magnetization. Our results open a prospect of research of relativistic topological Berry phases and dissipationless quantum transport in crystals of abundant elements and with a compensated antiparallel magnetic ordering at ambient conditions.

This paper reports on an experimental study on human-machine interface in LED manufacturing systems to measure the influence of information overload on user experience. The results are based on cognitive ergonomics. The experiment used eye-tracking methods and a questionnaire to gather data. The independent variables were interface complexity and user background. Interface complexity had three levels: high interface complexity, moderate interface complexity and low interface complexity. User background had two levels: the novice group and the expert group. The dependent variables included time to first fixation, fixations before and subjective feelings. A total of 38 operators participated in the experiment, and the results showed that (1) interface complexity caused a significant difference in time to first fixation (P \ 0.05) and fixations before (P \ 0.05). Furthermore, the results revealed significant differences between high complexity interfaces compared to low complexity interfaces (P \ 0.05). However, no significant differences were observed between moderate and low complexity interfaces or between moderate and high complexity interfaces (P [ 0.05); (2) user background significantly affected the user experience; (3) within the same complexity level, expert operators' cognitive workload was significantly lower than that of novice operators; and (4) there was no significant relationship between the interface complexity and the user's background. The study concludes that because interface complexity has a significant effect on the time taken to locate the target button on the screen, interface design should be as simple as possible, while still providing the necessary level of functionality.

Dispersions of poly(N-isopropylacrylamide-co-butyl methacrylate) (PNB) nanogels are known to exhibit reversible thermosensitive sol-gel phase behavior and can consequently be used in a wide range of biomedical applications. However, some dissatisfactory mechanical properties of PNB nanogels can limit their applications. In this paper, bacterial cellulose (BC) whiskers were first prepared by sulfuric acid hydrolysis and then nanosized by high-pressure homogenization for subsequent use in the preparation of BC whisker/PNB nanogel complexes (designated as BC/PNB). The mechanical properties of PNB was successfully enhanced, resulting in good biosafety. The BC/PNB nanogel dispersions exhibited phase transitions from swollen gel to shrunken gel with increasing temperature. In addition, differential scanning calorimetry (DSC) data showed that the thermosensitivity of PNB nanogels was retained. Rheological tests also indicated that BC/PNB nanogel complexes had stronger gel strengths when compared with PNB nanogels. The concentrated dispersions showed shear thinning behavior and improved toughness, both of which can play a key role in the medical applications of nanogel complexes. Furthermore, the BC/PNB nanogel complexes were noncytotoxic according to cytotoxicity and hemolysis tests. Concentrated BC/PNB nanogel dispersion displayed gel a forming capacity in situ by catheter injection, which indicates potential for a wide range of medical applications.

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