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In order to bridge the gap between the effects of superposition of unequal amplitude waves on superimposed waves, this paper investigates the effects of variable amplitude superimposed waves on piezoelectric actuators. The generation mechanism of traveling waves is explored from the principle of superposition of waves. A mathematical model of the piezoelectric beam is established based on the Euler-Bernoulli beam theory and the Lagrange equation. It is the first time that the effects of variable amplitude superimposed waves on motion performance are investigated from both theoretical and experimental perspectives. The effects of variable amplitude waves on kinematic performance are tested by changing different excitation frequencies, different positions and different loadings. The relationship between the amplitude ratio A and the motion performance is given. It is shown that there is an approximately linear negative correlation between the amplitude ratio and the motion performance when the amplitude ratio A = 1–2.4. This study provides a new idea for the generation of traveling waves and provides a reference for the design and application of piezoelectric actuators. [ABSTRACT FROM AUTHOR]

Background: Postoperative cognitive dysfunction (POCD) is a common complication of the central nervous system in elderly surgical patients. Structural MRI and arterial spin labelling (ASL) techniques found that the grey matter volume and cerebral perfusion in some specific brain areas are associated with the occurrence of POCD, but the results are inconsistent, and the predictive accuracy is low. We hypothesised that the combination of cortical grey matter volumetry and cerebral blood flow yield higher accuracy than either of the methods in discriminating the elderly individuals who are susceptible to POCD after abdominal surgery. Materials and Methods: Participants underwent neuropsychological testing before and after surgery. Postoperative cognitive dysfunction (POCD) was defined as a decrease in cognitive score of at least 20%. ASL-MRI and T1-weighted imaging were performed before surgery. We compared differences in cerebral blood flow (CBF) and cortical grey matter characteristics between POCD and non-POCD patients and generated receiver operating characteristic curves. Results: Out of 51 patients, 9 (17%) were diagnosed with POCD. CBF in the inferior frontal gyrus was lower in the POCD group compared to the non-POCD group (p < 0.001), and the volume of cortical grey matter in the anterior cingulate gyrus was higher in the POCD group (p < 0.001). The highest AUC value was 0.973. Conclusions: The combination of cortical grey matter volumetry and cerebral perfusion based on ASL-MRI has improved efficacy in the early warning of POCD to elderly abdominal surgical patients. [ABSTRACT FROM AUTHOR]

Summary: Cassava is one of the most important tropical crops, but it is seriously affected by cassava bacteria blight (CBB) caused by the bacterial pathogen Xanthomonas phaseoli pv manihotis (Xam). So far, how pathogen Xam infects and how host cassava defends during pathogen–host interaction remains elusive, restricting the prevention and control of CBB.Here, the illustration of HEAT SHOCK PROTEIN 90 kDa (MeHSP90.9) interacting proteins in both cassava and bacterial pathogen revealed the dual roles of MeHSP90.9 in cassava–Xam interaction.On the one hand, calmodulin‐domain protein kinase 1 (MeCPK1) directly interacted with MeHSP90.9 to promote its protein phosphorylation at serine 175 residue. The protein phosphorylation of MeHSP90.9 improved the transcriptional activation of MeHSP90.9 clients (SHI‐RELATED SEQUENCE 1 (MeSRS1) and MeWRKY20) to the downstream target genes (avrPphB Susceptible 3 (MePBS3) and N‐aceylserotonin O‐methyltransferase 2 (MeASMT2)) and immune responses. On the other hand, Xanthomonas outer protein C2 (XopC2) physically associated with MeHSP90.9 to inhibit its interaction with MeCPK1 and the corresponding protein phosphorylation by MeCPK1, so as to repress host immune responses and promote bacterial pathogen infection.In summary, these results provide new insights into genetic improvement of cassava disease resistance and extend our understanding of cassava–bacterial pathogen interaction. [ABSTRACT FROM AUTHOR]

Fast motion and high adaptability are crucial for the practical applications of miniature robots. However, combining these capabilities into a single robot skillfully is challenging, particularly in the domain of miniature structural design. Inspired by the amphibious motion of crocodiles in nature, a hollow piezoelectric miniature robot (HPMR) is proposed. The key benefit of the HPMR is to concurrently output the oscillating motion of the driving foot (oscillating mode) and the rotating motion of the internal rotor (rotating mode). That is, the mode of single‐energy‐input‐multimotion output allows the robot to balance the requirements of speed and adaptability. In the oscillating mode, HPMR can run at speeds of up to 12.3 BL s−1 and realize a displacement resolution of 0.3 μm. Following the conical rotor assembly, the rotor can operate at a speed of 890 rpm, with a displacement resolution of 7.28 mrad. In the rotating mode, the robot demonstrates its multitasking ability in moving amphibiously, carrying loads, running on surfaces with varying roughness, crossing obstacles, and resisting shocks. The results show that the HPMR is capable of fast, high‐resolution moving combined with high adaptability, opening up the possibility of using it for mobile detection tasks in real‐world settings. [ABSTRACT FROM AUTHOR]