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We demonstrate sizable, unencapsulated e-tattoos with transformable serpentine design and Cartan curve–inspired transfer., Epidermal electrophysiology is widely carried out for disease diagnosis, performance monitoring, human-machine interaction, etc. Compared with thick, stiff, and irritating gel electrodes, emerging tattoo-like epidermal electrodes offer much better wearability and versatility. However, state-of-the-art tattoo-like electrodes are limited in size (e.g., centimeters) to perform electrophysiology at scale due to challenges including large-area fabrication, skin lamination, and electrical interference from long interconnects. Therefore, we report large-area, soft, breathable, substrate- and encapsulation-free electrodes designed into transformable filamentary serpentines that can be rapidly fabricated by cut-and-paste method. We propose a Cartan curve–inspired transfer process to minimize strain in the electrodes when laminated on nondevelopable skin surfaces. Unwanted signals picked up by the unencapsulated interconnects can be eliminated through a previously unexplored electrical compensation strategy. These tattoo-like electrodes can comfortably cover the whole chest, forearm, or neck for applications such as multichannel electrocardiography, sign language recognition, prosthetic control or mapping of neck activities.

In this paper, the nonlinear vibration of a time-space coupled axial and torsional drill string system is investigated. Considering the surface morphology of rock, top drive system and mud, the drill string system is discretized by finite element method. The dynamic equations of the fully discrete drill string system based on rock surface morphology (SM) is established. Based on the surface morphology and strength of rock, the concept of rock surface state matrix is proposed. The stability and time domain response of the system are obtained by numerical simulation and compared with the multiple regeneration (MR) model. The results show that stick slip vibration and bit reversal are more likely to occur when drilling system cuts unhomogeneous rock, and stick slip vibration is the main reason to cause the drill bit impact rock. The stable driving torsional speed is lower than that of calculated by conventional models. In the calculation process, the volume conservation accuracy of the SM model is higher than that of the MR model. Moreover, the numerical convergence and efficiency of SM model are higher than that of MR model.

Quantum Dots are powerful imaging and tracking tools for a wide range of biomedical applications, especially in preparing molecular beacons, but its use is limited by the sensitivity of the electrostatic binding between streptavidin and QDs. In this investigation, we used EDC as a crosslinker and NHS as a stabilizer to activate the carboxyl groups of carboxyl-modified CdSe QDs for direct reaction with primary amines of amino-modifie d single-strande d DNA. The results suggest that CdSe QDs can be applied for preparing the molecular beacon hybridized with specific telomerase DNA.

The traditional English teaching mode has many shortcomings, which seriously affects the teaching effect. Multimedia English teaching model based on network can make up for its shortage to some extent. The foundation of this teaching mode is the multimedia courseware that adapts to the current requirements. So, the study of network multimedia courseware has an important practical significance and value. In this paper, the significance of network multimedia courseware for English teaching is summarized first of all according to the current status of English teaching. And then, the basic theories and principles of network multimedia courseware are discussed. Finally, the promotion method, existing problems and solutions about network multimedia courseware are introduced. This paper is the practical experience about multimedia English teaching for several years, which has some promotion role to the current cultural protection and art exchanges.

With the rapid progress in science and technology, the human society advances from industrial society to post-industrial society. People pay more and more attention to the role of information. Objective demand for information greatly stimulates the development of information technology, such as TCM Literature and Database, and global information network has been set up quickly. Information resources are delivered freely on the "information superhighway", and the dream of global information resource sharing is finally realized.