The fruitful advancement in synthetic chemistry of the title families of complex diterpenes has stimulated and enjoyed strategic balance between building the skeletons and installing the functional groups.

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Flexible bioinspired mesostructures and electronic devices have recently attracted intense attention because of their widespread application in microelectromechanical systems (MEMS), reconfigurable electronics, health-monitoring systems, etc. Among various geometric constructions, 3D flexible bioinspired architectures are of particular interest, since they can provide new functions and capabilities, compared to their 2D counterparts. However, 3D electronic device systems usually undergo complicated mechanical loading in practical operation, resulting in complex deformation modes and elusive failure mechanisms. The development of mechanically robust flexible 3D electronics that can undergo extreme compression without irreversible collapse or fracture remains a challenge. Here, inspired by the multilayer mesostructure of Enhydra lutris fur, we introduce the design and assembly of multilayer cage architectures capable of multistage load bearing and collapse prevention under large out-of-plane compression. Combined in situ experiments and mechanical modeling show that the multistage mechanical responses of the developed bionic architectures can be fine-tuned by tailoring the microstructural geometries. The integration of functional layers of gold and piezoelectric polymer allows the development of a flexible multifunctional sensor that can simultaneously achieve the dynamic sensing of compressive forces and temperatures. The demonstrated capabilities and performances of fast response speed, tunable measurement range, excellent flexibility, and reliability suggest potential uses in MEMS, robotics and biointegrated electronics.

Water vapor existing inside internal end-face gaps of optical components of an optical fiber H2O sensing system makes it possible to influence the measurement accuracy and stability. The influence principle has been briefly analyzed based on the structure of three main optical components: a distributed feedback laser diode (DFB-LD), a collimator, and a photoelectric diode (PD). With application of a differential technique, the influence of water vapor inside the DFB-LD can be removed. With reasonable recombination of the collimator and the PD in a dual-beam detection system, the influence of water vapor inside the collimator and the PD's end-face gaps has been suppressed from more than 1.57×10(-3) to as low as -2.175×10(-5) in absorbance. After H2O isolation processing water vapor inside the end-face gaps of the DFB-LD, the collimator, and the PD can be utilized as a reference to design a simple but feasible H2O sensor. As a result, good linearity with an R2 of 0.9964 has been realized in a concentration range of 39-2110 ppm during an application test, and a long-term test of the designed H2O sensor against the S8000 with a difference of 10 ppm has been achieved.