Downscaling of printable OFETs and approaches for steep subthreshold swing have been summarized and discussed.

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The artificial ground-freezing method has the dual effect of ground reinforcement and waterproof sealing, and the frozen curtain can be designed flexibly. It is widely used in the construction of cross passages for shield tunnels in soft ground with high groundwater levels. However, due to the lack of in situ monitoring data, it remains difficult to determine the frost heave pressure acting upon a tunnel. In this study, based on the use of an anti-freezing pad-type earth pressure gauge, in situ monitoring was carried out to measure the frost heave pressure acting upon tunnel segments during the construction of cross passages for the Shanghai Yangtze River Tunnel. The monitoring results show that the earth pressure acting upon the tunnel could decrease dramatically during freezing, and this kind of decrease can take place suddenly and unpredictably, which can be illustrated using the finite element method. The maximum measured frost heave pressure during freezing and cross passage excavation was approximately 0.2 MPa, which was much smaller than the predicted value. Combining the distribution of temperature in the ground and construction countermeasures, the observed phenomena are mainly related to three factors: water migration during the freezing process, the tunnel–ground interaction, and the countermeasure of pressure release holes. The tunnel showed a horizontal extension–deformation, which was consistent with the releasing frost heave pressure acting upon it.

Organic field effect transistors (OFETs) are a promising technology for developing truly flexible, stretchable and bio-compatible integrated electronics. Understanding the contact resistance mechanisms and introducing strategies to minimize the contact resistance is vital for the continuous performance improvement of OFETs. This paper firstly discusses the suitability of various device structures for short channel OFETs and fine resolution integration. After describing the formation of the contact resistance composed of the injection and access parts, this paper comprehensively reviews approaches for reducing contact resistance with bottom contact structure OFETs, including by interface engineering and doping the organic semiconductor layer. The pros and cons of each approach are discussed in detail. It is concluded that a combination of various techniques is required to minimize the contact resistance for fine resolution integration.

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With the development of nanotechnology, nanomaterials have been used in dental fields over the past years. Among them, graphene and its derivatives have attracted great attentions, owing to their excellent physicochemical property, morphology, biocompatibility, multi-differentiation activity, and antimicrobial activity. In our review, we summarized the recent progress about their applications on the dentistry. The synthesis methods, structures, and properties of graphene-based materials are discussed. Then, the dental applications of graphene-based materials are emphatically collected and described. Finally, the challenges and outlooks of graphene-based nanomaterials on the dental applications are discussed in this paper, aiming at inspiring more excellent studies.

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