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In this letter, amorphous indium-gallium-zinc-tin oxide ( ${a}$ -IGZTO) thin-film transistors (TFTs) were characterized with a bottom gate structure, where a single target with three cation composition ratios were used to deposit the a-IGZTO channel layer. Remarkably, ${a}$ -In $_{{0.60}}$ Ga $_{{0.14}}$ Zn $_{{0.20}}$ Sn $_{{0.06}}\text{O}$ TFTs exhibited exceptional performance, featuring a significantly high field-effect mobility of 90.2 cm2/Vs, a low subthreshold swing of 0.10 V/decade, a threshold voltage ( ${V} _{\text {TH}}$ ) of −0.40 V, and an ${I} _{\text {ON/OFF}}$ ratio of $3\times 10^{{8}}$ . Furthermore, the TFTs demonstrated excellent bias temperature stress (BTS) reliability, with minimal variations in ${V} _{\text {TH}}$ ( $\Delta {V}_{\text {TH}}$ ) less than ±0.08 V under negative and positive bias temperature stress at 60 °C for 1 hour. The impressive performance and reliability observed in these TFTs can be attributed to the synergistic percolation of In $^{\text {3+}}$ and Sn $^{\text {4+}}$ and the beneficial hydrogen-doping effect near Sn cations.

Recently, the locomotion of a microrobot wirelessly actuated by electromagnetic actuation systems has been studied in many ways. Because of the inherent characteristics of an electromagnetic field, however, the magnetic field of each coil in the electromagnetic actuation system induces magnetic field interferences, which can distort the desired electromagnetic field, preventing the microrobot from following the desired path. In this article, we used two pairs of Helmholtz coils and two pairs of Maxwell coils in a two-dimensional electromagnetic actuation system. Generally, the two pairs of Helmholtz coils generate the torque for the rotation of the microrobot and the two pairs of Maxwell coils generate the propulsion force of the microrobot. Both pairs of Helmholtz and Maxwell coils have to work to simultaneously align and propel the microrobot in a desired direction. In this situation, however, the electromagnetic fields produced by the Helmholtz coils can interfere with those produced by the Maxwell coils. This interference is closely dependent on the position of the microrobot in the region of interest inside the electromagnetic coils system. This means that the alignment direction and propulsion force of the microrobot can be distorted according to the position of the microrobot. Therefore, we propose a compensation algorithm for the electromagnetic field interference using the position information of the microrobot to correct the magnetic field interferences. First, the interference of an electromagnetic field obeying the Biot–Savart law is analyzed by numerical analysis. Second, a position-based compensation algorithm for the locomotion of a microrobot is proposed. Various locomotion tests of a microrobot verified that the proposed compensation algorithm could reduce the normalized average tracking error from 5.25% to 1.92%.

An interview with Dr. Cho Zang-hee is presented. When asked about the difference between the Korean and U.S. universities, he refers on the dissimilarities of the spending program of their received donations. He emphasizes that the quality of the professors is more important than the students. He added that a university's competitiveness is closely related to national competitiveness.

Summary: Novel organic-inorganic hybrid bioactive bone cements containing bisphenol‐A‐glycidyl methacrylate (Bis‐GMA) derivatives and a bioactive inorganic filler were prepared for orthopedic applications. The Bis‐GMA derivatives, such as 3MA and a 3MA mixture (3MA mix), were synthesized by blocking one or two of the hydroxyl groups of the Bis‐GMA so as to use it as a prepolymer. Four organic prepolymers, such as Bis‐GMA, 3MA, 3MA 50 and 3MA mix, and an inorganic filler, AW‐GC, were used for the preparation of the bioactive bone cements and their characteristics were evaluated. As compared with the Bis‐GMA control, the new bioactive bone cements containing the Bis‐GMA derivatives exhibited appropriate curing times, low polymerization shrinkage, low water absorption and solubility as well as high mechanical properties. In particular, the bioactive bone cement containing 3MA mix and AW‐GC had higher bending and compressive strengths than the Bis‐GMA one.Curing time and polymerization shrinkage on various prepolymers of bioactive bone cements.