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Solution processable perovskites have made remarkable strides in direct planar X-ray detectors, promising to reshape X-ray detector industry. Herein, we discuss prevailing challenges, research opportunities, and their synergies with cutting-edge technologies that will benefit both human society and scientific research.

Detection of haloalkanes is of great industrial and scientific importance because some haloalkanes are found serious biological and atmospheric issues. The development of a flexible, wearable sensing device for haloalkane assays is highly desired. Here, we develop a paper-based microfluidic sensor to achieve low-cost, high-throughput, and convenient detection of haloalkanes using perovskite nanocrystals as a nanoprobe through anion exchanging. We demonstrate that the CsPbX3 (X = Cl, Br, or I) nanocrystals are selectively and sensitively in response to haloalkanes (CH2Cl2, CH2Br2), and their concentrations can be determined as a function of photoluminescence spectral shifts of perovskite nanocrystals. In particular, an addition of nucleophilic trialkyl phosphines (TOP) or a UV-photon-induced electron transfer from CsPbX3 nanocrystals is responsible for achieving fast sensing of haloalkanes. We further fabricate a paper-based multichannel microfluidic sensor to implement fast colorimetric assays of CH2Cl2 and CH2Br2. We also demonstrate a direct experimental observation on chemical kinetics of anion exchanging in lead-halide perovskite nanocrystals using a slow solvent diffusion strategy. Our studies may offer an opportunity to develop flexible, wearable microfluidic sensors for haloalkane sensing, and advance the in-depth fundamental understanding of the physical origin of anion-exchanged nanocrystals.

X-ray imaging is a low-cost, powerful technology that has been extensively used in medical diagnosis and industrial nondestructive inspection. The ability of X-rays to penetrate through the body presents great advances for noninvasive imaging of its internal structure. In particular, the technological importance of X-ray imaging has led to the rapid development of high-performance X-ray detectors and the associated imaging applications. Here, we present an overview of the recent development of X-ray imaging-related technologies since the discovery of X-rays in the 1890s and discuss the fundamental mechanism of diverse X-ray imaging instruments, as well as their advantages and disadvantages on X-ray imaging performance. We also highlight various applications of advanced X-ray imaging in a diversity of fields. We further discuss future research directions and challenges in developing advanced next-generation materials that are crucial to the fabrication of flexible, low-dose, high-resolution X-ray imaging detectors.

Abstract Background Open pilon fractures combined with sizeable segmental bone defects are rare, difficult to treat, and often result in the loss of ankle joint function. The purpose of this study was to determine clinical outcomes in patients with open pilon fractures and sizeable segmental bone defects treated by limited ORIF combined with an Ilizarov external fixator. Methods We conducted a retrospective analysis of open pilon fractures with sizeable segmental bone defects treated by limited ORIF combined with the Ilizarov external fixator strategy between July 2014 and August 2019. All patients were included for assessments of fracture healing and infection rates. Ankle functional outcomes were assessed in all patients according to the Paley criteria and American Orthopedic Foot and Ankle Society Score (AOFAS) at least 24 months post-injury. Results All patients were followed up for a mean of 41.09 months. The mean bone defect size was 5.64 ± 1.21 cm. The average EFI and BTI were 1.56 ± 0.28 months/cm and 11.12 ± 0.74 days/cm, respectively. According to the Paley evaluation system, the success rate of ankle joint reconstruction was 64% (7/11). The mean score based on the AOFAS functional assessment was 77.73 ± 8.87. Five patients showed posttraumatic arthritis, one of whom required ankle arthrodesis. Three patients developed pin site infections, and one patient developed a deep infection after bone grafting. Conclusion The strategy of limited ORIF combined with an Ilizarov external fixator can restore ankle function in most patients with complex open tibial pilon fractures. Ankle stiffness, pin tract infection, and traumatic arthritis were the most common complications associated with this therapy.