In search of high-performance field-effect transistors (FETs) made of atomic thin semiconductors, indium selenide (InSe) has held great promise because of its high intrinsic mobility and moderate electronic band gap (1.26 eV). Yet the performance of InSe FETs is decisively determined by the surface oxidation of InSe taking place spontaneously in ambient conditions, setting up a mobility ceiling and causing an uncontrollable current hysteresis. Encapsulation by hexagonal boron nitride (h-BN) has been currently used to cope with this deterioration. Here, we provide insights into the role of surface oxides played in device performance and introduce a dry-oxidation process that forms a dense capping layer on top, where InSe FETs exhibit a record-high two-probe mobility of 423 cm/V·s at room temperature and 1006 cm/V·s at liquid nitrogen temperature without the use of h-BN encapsulation or high-κ dielectric screening. Ultrahigh on/off current ratio of >10 and current density of 365 μA/μm can be readily achieved without elaborate engineering of drain/source contacts or gating technique. Thickness-dependent device properties are also studied, with optimized performance shown in FETs comprising of 13 nm thick InSe. The high performance of InSe FETs with ultrathin dry oxide is attributed to the effective unpinning of the Fermi level at the metal contacts, resulting in a low Schottky barrier height of 40 meV in an optimized channel thickness.

We developed a tissue-engineered vascular graft (TEVG) for use in children and present results of a U.S. Food and Drug Administration (FDA)–approved clinical trial evaluating this graft in patients with single-ventricle cardiac anomalies. The TEVG was used as a Fontan conduit to connect the inferior vena cava and pulmonary artery, but a high incidence of graft narrowing manifested within the first 6 months, which was treated successfully with angioplasty. To elucidate mechanisms underlying this early stenosis, we used a data-informed, computational model to perform in silico parametric studies of TEVG development. The simulations predicted early stenosis as observed in our clinical trial but suggested further that such narrowing could reverse spontaneously through an inflammation-driven, mechano-mediated mechanism. We tested this unexpected, model-generated hypothesis by implanting TEVGs in an ovine inferior vena cava interposition graft model, which confirmed the prediction that TEVG stenosis resolved spontaneously and was typically well tolerated. These findings have important implications for our translational research because they suggest that angioplasty may be safely avoided in patients with asymptomatic early stenosis, although there will remain a need for appropriate medical monitoring. The simulations further predicted that the degree of reversible narrowing can be mitigated by altering the scaffold design to attenuate early inflammation and increase mechano-sensing by the synthetic cells, thus suggesting a new paradigm for optimizing next-generation TEVGs. We submit that there is considerable translational advantage to combined computational-experimental studies when designing cutting-edge technologies and their clinical management.

In this letter, we present and analyze the device performance of the mixed host ͑MH͒ organic light-emitting devices ͑OLEDs͒. The host of the emitting layer ͑EML͒ material in this device consists of a hole transport layer ͑HTL͒ and an electron transport layer ͑ETL͒ fabricated by coevaporation. The bipolar transport characteristic of the MH layer helps to reduce the driving voltage. Device lifetime is increased due to the elimination of the sharp boundary of the HTL/EML interface. Combining the MH structure with a high mobility electron ETL material, bis͑10-hydroxybenzo͓h͔qinolinato͒beryllium, the OLED has shown a brightness of 27 600 cd/ m 2 at a driving voltage of 5 V, and a lifetime four times longer than that of a conventional OLED.

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