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X-ray detection, which plays an important role in medical and industrial fields, usually relies on inorganic scintillators to convert X-rays to visible photons; although several high-quantum-yield fluorescent molecules have been tested as scintillators, they are generally less efficient. High-energy radiation can ionize molecules and create secondary electrons and ions. As a result, a high fraction of triplet states is generated, which act as scintillation loss channels. Here we found that X-ray-induced triplet excitons can be exploited for emission through very rapid, thermally activated up-conversion. We report scintillators based on three thermally activated delayed fluorescence molecules with different emission bands, which showed significantly higher efficiency than conventional anthracene-based scintillators. X-ray imaging with 16.6 line pairs mm −1 resolution was also demonstrated. These results highlight the importance of efficient and prompt harvesting of triplet excitons for efficient X-ray scintillation and radiation detection. Triplet exciton harvesting through thermally activated delayed fluorescence is shown to be effective also under X-ray excitation, increasing the efficiency and imaging quality of X-ray detectors based on organic scintillation.

There is great interest in the development of micromotors which can convert energy to motion in sub-millimeter dimensions. Micromachines take the micromotor concept a step further, comprising complex systems in which multiple components work in concert to effectively realize complex mechanical tasks. Here we introduce light-driven micromotors and micromachines that rely on optoelectronic tweezers (OET). Using a circular micro-gear as a unit component, we demonstrate a range of new functionalities, including a touchless micro-feed-roller that allows the programming of precise three-dimensional particle trajectories, multi-component micro-gear trains that serve as torque- or velocity-amplifiers, and micro-rack-and-pinion systems that serve as microfluidic valves. These sophisticated systems suggest great potential for complex micromachines in the future, for application in microrobotics, micromanipulation, microfluidics, and beyond. Light-driven micromotors can convert energy to motion in sub-millimeter dimensions. Here, the authors extend this concept and introduce reconfigurable micromachines with multiple components, driven by optoelectronic tweezers, and demonstrate new functionalities.

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of death and it has been confirmed that increased low density lipoprotein cholesterol (LDL-C) is an independent risk factor for atherosclerosis. Recently, the increasing evidence has showed that hypertriglyceridemia is associated with incremental ASCVD risk. But the proatherogenic mechanism of triglyceride (TG) remains unclear. Therefore, this article focuses on the clinical studies and proatherogenic mechanism related to hypertriglyceridemia, in order to provide reference for the prevention and treatment of ASCVD.

Metal halide perovskites are promising for next-generation flexible photodetectors owing to their low-temperature solution processability, mechanical flexibility, and excellent photoelectric properties. However, the defects and notorious ion migration in polycrystalline metal halide perovskites often lead to high and unstable dark current, thus deteriorating their detection limit and long-term operations. Here, we propose an electrical field modulation strategy to significantly reduce the dark current of metal halide perovskites-based flexible photodetector more than 1000 times (from ~5 nA to ~5 pA). Meanwhile, ion migration in metal halide perovskites is effectively suppressed, and the metal halide perovskites-based flexible photodetector shows a long-term continuous operational stability (~8000 s) with low signal drift (~4.2 × 10 −4 pA per second) and ultralow dark current drift (~1.3 × 10 −5 pA per second). Benefitting from the electrical modulation strategy, a high signal-to-noise ratio wearable photoplethysmography sensor and an active-matrix photodetector array for weak light imaging are successfully demonstrated. This work offers a universal strategy to improve the performance of metal halide perovskites for wearable flexible photodetector and image sensor applications. Defects and ion migration in perovskites hinder their potential as active material for flexible photodetectors. Here, the authors provide an electrical field modulation strategy to enhance the operational stability and the signal-to-noise ratio of flexible perovskite photodetectors.

MicroRNAs are endogenous single-stranded non-coding small RNA molecules that can be secreted into the circulation and exist stably. They usually exhibit aberrant expression under different physiological and pathological conditions. Recently, differentially expressed circulating microRNAs were focused on as potential biomarkers for cancer screening. We herein review the role of circulating microRNAs for cancer diagnosis, tumor subtype classification, chemo- or radio-resistance monitoring, and outcome prognosis. Moreover, circulating microRNAs still have several issues hindering their reliability for the practical clinical application. Future studies need to elucidate further potential application of circulating microRNAs as specific and sensitive markers for clinical diagnosis or prognosis in cancers.

Although perovskite X-ray detectors have revealed promising properties, their dark currents are usually hundreds of times larger than the practical requirements. Here, we report a detector architecture with a unique shunting electrode working as a blanking unit to suppress dark current, and it theoretically can be reduced to zero. We experimentally fabricate the dark-current-shunting X-ray detector, which exhibits a record-low dark current of 51.1 fA at 5 V mm −1 , a detection limit of 7.84 nGy air  s −1 , and a sensitivity of 1.3 × 10 4  μC Gy air −1  cm −2 . The signal-to-noise ratio of our polycrystalline perovskite-based detector is even outperforming many previously reported state-of-the-art single crystal-based X-ray detectors by serval orders of magnitude. Finally, the proof-of-concept X-ray imaging of a 64 × 64 pixels dark-current-shunting detector array is successfully demonstrated. This work provides a device strategy to fundamentally reduce dark current and enhance the signal-to-noise ratio of X-ray detectors and photodetectors in general. The high dark current of perovskite photodetectors hinders the full potential of perovskites as active material for X-ray detectors. Here, Jin et al. provide a strategy to reduce the dark current to zero and massively enhance the signal-to-noise ratio of perovskite X-ray detectors and photodetectors.

Zero-dimensional MoS 2 quantum dots (QDs) possess distinct physical and chemical properties, which have garnered them considerable attention and facilitates their use in a broad range of applications. In this study, we prepared monolayer MoS 2 QDs using temporally shaped femtosecond laser ablation of bulk MoS 2 targets in water. The morphology, crystal structures, chemical, and optical properties of the MoS 2 QDs were characterized by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, UV–vis absorption spectra, and photoluminescence spectra. The analysis results show that highly pure, uniform, and monolayer MoS 2 QDs can be successfully prepared. Moreover, by temporally shaping a conventional single pulse into a two-subpulse train, the production rate of MoS 2 nanomaterials (including nanosheets, nanoparticles, and QDs) and the ratio of small size MoS 2 QDs can be substantially improved. The underlying mechanism is a combination of multilevel photoexfoliation of monolayer MoS 2 and water photoionization–enhanced light absorption. The as-prepared MoS 2 QDs exhibit excellent electrocatalytic activity for hydrogen evolution reactions because of the abundant active edge sites, high specific surface area, and excellent electrical conductivity. Thus, this study provides a simple and green alternative strategy for the preparation of monolayer QDs of transition metal dichalcogenides or other layered materials.

Exposure to polycyclic aromatic hydrocarbons (PAHs) during pregnancy may pose adverse health risk to both the mothers and babies. In the present study, 188 pregnant women of different trimesters were recruited in Guangzhou, south China, and nine hydroxyl PAHs (OH-PAHs) and a biomarker of DNA oxidative damage, 8-hydroxy-2′-deoxyguanosine (8-OHdG), were determined in their urine samples. All OH-PAHs except for 4-hydroxyphenanthrene and 6-hydroxychrysene were found in > 90% samples, with total concentration in the range of 0.52 to 42.9 μg/g creatinine. In general, concentration levels of OH-PAHs in pregnant women were lower than those in general population in the same research area but with higher levels in working women than in housewives. The mean daily intakes of PAHs from dietary estimated by urinary OH-PAHs were 0.021, 0.004, 0.047, and 0.030 μg/kg_bw/day for naphthalene, fluorene, phenanthrene, and pyrene, respectively, which were much lower than the reference doses (20, 30, and 40 μg/kg_bw/day for naphthalene, pyrene, and fluorene, respectively) derived from chronic oral exposure data by the United States Environmental Protection Agency. The low exposure levels of PAHs may be attributed to the traditional dietary taboo of Chinese pregnant women, which is to minimize the consumption of “toxic” food. The concentrations of 8-OHdG (4.67–49.4 μg/g creatinine) were significantly positively correlated with concentrations of several OH-PAHs, such as metabolites of naphthalene, fluorene, and phenanthrene ( r  = 0.3–0.6). In addition, the concentrations of 8-OHdG were higher in working women than in housewives when exposed to the same levels of PAHs, partly indicating the possible relation between work-related pressure for working women and the oxidative stress.

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality, and detecting circulating tumor cells (CTCs) is crucial for early diagnosis and metastasis monitoring. Conventional staining-based cytology is costly, time-consuming, and often compromises sample integrity. In this study, we employed a combined digital holography (DH) and fluorescence imaging approach to develop a virtual staining framework for transforming quantitative phase imaging (QPI) data into interpretable pseudo-stained images. To the best of our knowledge, this is the first application of such a framework to colorectal cancer CTC detection. In our experiments, green fluorescent protein (GFP)-labeled HCT116 cells-generated through lentiviral transfection-were mixed with peripheral blood mononuclear cells (PBMCs) to create training datasets. The trained network achieved 99% classification accuracy and demonstrated strong generalization to unseen donors. This DH-fluorescence-based virtual staining method preserves cell integrity while enabling rapid, label-free, and low-cost liquid cytology diagnostics, highlighting its potential for non-invasive cancer detection and monitoring.

High-precision automated detection of metal welding defects is critical to ensuring structural safety and reliability in modern manufacturing. However, existing methods often struggle with insufficient fine-grained feature retention, low efficiency in multi-scale information fusion, and vulnerability to complex background interference, resulting in low detection accuracy. This work addresses the limitations by introducing the DEIM-SFA, a novel detection framework designed for automated visual inspection in industrial machine vision sensors. The model introduces a novel structure-aware dynamic convolution (SPD-Conv), effectively focusing on the fine-grained structure of defects while suppressing background noise interference; an innovative multi-scale dynamic fusion pyramid (FTPN) architecture is designed to achieve efficient and adaptive aggregation of feature information from different receptive fields, ensuring consistent detection of multi-scale targets; combined with a lightweight and efficient multi-scale attention module (EMA), this further enhances the model’s ability to locate salient regions in complex scenarios. The network is evaluated on a self-built welding defect dataset. Experimental results show that DEIM-SFA achieves a 3.9% improvement in mAP50 compared to the baseline model, mAP75 by 4.3%, mAP50–95 by 3.7%, and Recall by 1.4%. The model exhibits consistently significant superiority in detection accuracy across targets of various sizes, while maintaining well-balanced model complexity and inference efficiency, comprehensively surpassing existing state-of-the-art (SOTA) methods.