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Dehydration has been a key limiting factor for the operation of conductive hydrogels in practical application. Here, we report self-healable ionic skins that can self-regulate their internal moisture level by capturing extenral moistures via hygroscopic ion-coordinated polymer backbones through antipolyelectrolyte effect. Results show the ionic skin can maintain its mechanical and electrical functions over 16 months in the ambient environment with high stretchability (fracture stretch ∼2216 %) and conductivity (23.5 mS/cm). The moisture self-regulating capability is further demonstrated by repeated exposures to harsh environments such as 200°C heating, freezing, and vacuum drying with recovered conductivity and stretchability. Their reversible ionic and hydrogen bonds also enable self-healing feature as a sample with the fully cut-through damage can restore its conductivity after 24 h at 40 % relative humidity. Utilizing the ionic skin as a building block, self-healing flexible piezoelecret sensors have been constructed to monitor physiological signals. Together with a facile transfer-printing process, a self-powered sensing system with a self-healable supercapacitor and humidity sensor has been successfully demonstrated. These results illustrate broad-ranging possibilities for the ionic skins in applications such as energy storage, wearable sensors, and human-machine interfaces.

Objective To carry out offline, online and online-offline blended histology experimental teaching for medical students of different grades, and analyze the effect of various teaching modes. Methods The online-offline hybrid teaching system was constructed through virtual slides website and Moodle platform. The teaching effect was evaluated according to experimental scores and questionnaire feedback. Results The experimental score with online-offline blended teaching mode was significantly higher than that with offline or online teaching modes(P＜0.01).The students were satisfied with the online-offline blended mode (98.21%, 96.43%). Conclusions Application of online-offline blended teaching mode in the histology experimental course could improve the teaching quality and achieve better teaching effects.

Adult hippocampal neurogenesis (AHN), essential for the plasticity of hippocampal structure and function, may be disrupted in Alzheimer's disease (AD). However, the relationship between the changes in AHN and AD‐related pathology in humans remains uncertain. By utilizing advanced immunostaining techniques, we could identify multiple biomarkers representing different stages of AHN in postmortem human hippocampal tissue that exhibited various AD‐related neuropathological changes. In this study, we observed a significant presence of neurogenic cells in the hippocampus's dentate gyrus (DG) region in 30 individuals, including 14 individuals diagnosed with AD‐related neuropathological changes and the remaining 16 individuals without any neurological diseases. Further investigation revealed that patients with AD exhibited pronounced astrogliosis and reduced neurogenesis. Specifically, the number of neuroblasts, immature and early mature granule cells decreased significantly as AD advanced. Although the number of neural stem cells (NSCs) remained unchanged in AD patients compared with mentally healthy individuals, they tended to be more quiescent state regulated by Notch and bone morphogenetic protein (BMP) signaling pathways. These abnormalities were strongly associated with the neuropathological alterations in AD patients. These research findings provide potential insights into the underlying mechanisms that underpin the pathogenesis of AD. [ABSTRACT FROM AUTHOR]

Damage detection is of great importance for structural construction management and safety. In this study, an ultra-sensitive flexible piezoelectret sensor for damage monitoring in structural health monitoring (SHM) is designed and fabricated, based on excellent electromechanical properties and piezoelectric response characteristics of electret films. The charge stability of the piezoelectret sensor was demonstrated by continuous potential measurement experiments. The experimentally measured piezoelectret coefficient is 6610 pC/N, which is about 10 times that of ordinary piezoelectric ceramics and proves the high sensitivity of piezoelectret. A series of comparative experiments on the piezoelectret sensor and piezoelectric ceramics demonstrate the high performance of the former. According to the damage detection test results, the damage index of cement mortar specimens was obtained. The linear relationship between the damage index and the crack widths proves the excellent performance of the piezoelectret sensor. A piezoelectret array is also used to detect cracks in cement mortar specimens, and can roughly estimate the depth of the fracture based on the damage index (DI) value of the sensing array. [ABSTRACT FROM AUTHOR]