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Thermal quenching, in which light emission experiences a loss with increasing temperature, broadly limits luminescent efficiency at higher temperature in optical materials, such as lighting phosphors1–3 and fluorescent probes4–6. Thermal quenching is commonly caused by the increased activity of phonons that leverages the non-radiative relaxation pathways. Here, we report a kind of heat-favourable phonons existing at the surface of lanthanide-doped upconversion nanomaterials to combat thermal quenching. It favours energy transfer from sensitizers to activators to pump up the intermediate excited-state upconversion process. We identify that the oxygen moiety chelating Yb3+ ions, [Yb···O], is the key underpinning this enhancement. We demonstrate an approximately 2,000-fold enhancement in blue emission for 9.7 nm Yb3+-Tm3+ co-doped nanoparticles at 453 K. This strategy not only provides a powerful solution to illuminate the dark layer of ultra-small upconversion nanoparticles, but also suggests a new pathway to build high-efficiency upconversion systems.

The intracellular metabolism of organelles, like lysosomes and mitochondria, is highly coordinated spatiotemporally and functionally. The activities of lysosomal enzymes significantly rely on the cytoplasmic temperature, and heat is constantly released by mitochondria as the byproduct of adenosine triphosphate (ATP) generation during active metabolism. Here, we developed temperature-sensitive LysoDots and MitoDots to monitor the in situ thermal dynamics of lysosomes and mitochondria. The design is based on upconversion nanoparticles (UCNPs) with high-density surface modifications to achieve the exceptionally high sensitivity of 2.7% K−1 and low uncertainty of 0.8 K for nanothermometry to be used in living cells. We show the measurement is independent of the ion concentrations and pH values. With Ca2+ ion shock, the temperatures of both lysosomes and mitochondria increased by ∼2 to 4°C. Intriguingly, with chloroquine (CQ) treatment, the lysosomal temperature was observed to decrease by up to ∼3 °C, while mitochondria remained relatively stable. Lastly, with oxidative phosphorylation inhibitor treatment, we observed an ∼3 to 7°C temperature increase and a thermal transition from mitochondria to lysosomes. These observations indicate different metabolic pathways and thermal transitions between lysosomes and mitochondria inside HeLa cells. The nanothermometry probes provide a powerful tool for multimodality functional imaging of subcellular organelles and interactions with high spatial, temporal, and thermal dynamics resolutions.

To clarify the relationship between GNSS (Global Navigation Satellite System) crustal deformation and the preparation of strong earthquakes in the western Chinese Mainland, a series of methods including velocity field, strain rate field, and strain parameter time series are adopted based on the GNSS observation data from the CMONOC (Crustal Movement Observation Network of China). The abnormal characteristics of crustal deformation movement before the M  ≥ 5 earthquakes in the area since 1999 are studied. The corresponding variety of the crustal movement before earthquakes is discussed in combination with the seismogenic structure of earthquakes. The abnormalities of the GNSS velocity field, strain field, and strain parameter time series before earthquakes with different magnitudes are proposed. Finally, the anomaly criterion before medium-strong-large earthquakes in the western Chinese Mainland is proposed according to the GNSS and its combination with the characteristics of geological structure. The results can provide a basis for the forecasting of the trend and location of medium-strong-large earthquakes in the western Chinese Mainland.

Skeletal disorders are commonly diagnosed by X-ray imaging, but the radiation limits its use. Optical imaging through the near-infrared-II window (NIR-II, 1000–1700 nm) can penetrate deep tissues without radiation risk, but the targeting of contrast agent is non-specific. Here, we report that lanthanide-doped nanocrystals can passively target the bone marrow, which can be effective for over two months. We therefore develop the high-resolution NIR-II imaging method for bone disease diagnosis, including the 3D bone imaging instrumentation to show the intravital bone morphology. We demonstrate the monitoring of 1 mm bone defects with spatial resolution comparable to the X-ray imaging result. Moreover, NIR-II imaging can reveal the early onset inflammation as the synovitis in the early stage of rheumatoid arthritis, comparable to micro computed tomography (μCT) in diagnosis of osteoarthritis, including the symptoms of osteophyte and hyperostosis in the knee joint. Skeletal disorders are commonly diagnosed by X-ray imaging, but the radiation limits its use. Here, the authors show that intravital NIR-II bone imaging is effective in diagnosis of a series of common bone diseases non-invasively in mice.

Normal faults play a key role in accommodating extensional deformation within the South Tibet Rift. The MS 6.8 Tingri earthquake of 7 January 2025 therefore provides a rare opportunity to investigate how these normal faults accommodate east–west extension driven by India–Eurasia convergence. Using Sentinel-1 synthetic aperture radar (SAR) imagery, we measured coseismic surface deformation and inverted the slip distribution, revealing a maximum line-of-sight (LOS) displacement of 1.85 m. Combining Bayesian inference with joint fault-slip inversion, we constrain the seismogenic fault as a west-dipping normal fault (strike 183°, dip 42.5°, rake ~–115°), exhibiting a maximum slip of 5.36 m at shallow depth. The derived moment magnitude (MW 7.12, seismic moment 3.32 × 1019 N·m) agrees well with the USGS estimate (MW 7.1). Coulomb stress modeling suggests stress decreases along fault flanks and significant stress loading (>0.01 MPa) at rupture terminations and adjacent north–south trending faults, implying elevated aftershock potential and possible fault triggering. GNSS velocity fields and strain rate inversion indicate a regional stress regime with a principal compressive axis (σ1) oriented ~341° (NNW) and extensional axis (σ3) at ~73° (ESE), consistent with east–west extension and north–south shortening. The fault exhibits oblique-normal slip, attributed to the non-orthogonal orientation of the fault plane relative to the stress field, resulting in right-lateral shear. Within the framework of the paired general-shear (PGS) deformation, this oblique slip reflects localized extensional deformation within a distributed dextral shear zone. These findings support a model of strain partitioning under regional shear and provide insights into fault segmentation and kinematics in rift systems.

Upconversion luminescent materials (UCLMs) have garnered significant attention due to their broad potential applications in fields such as display technology, biological imaging, and optical sensing. However, optimizing crystal phase and morphology remains a challenge. This study systematically investigates the effects of phase transformation and morphology control on the upconversion luminescent properties of K3GaF6:Er3+. By comparing different synthesis methods, we found that the hydrothermal method effectively facilitated the transformation of the NaxK3-xGaF6 crystal phase from cubic to monoclinic, with Na+/K+ ions playing a key role in the preparation process. Furthermore, the hydrothermal method significantly optimized the particle morphology, resulting in the formation of uniform octahedral structures. The 657 nm red emission intensity of the monoclinic phase sample doped with Er3+ was enhanced by 30 times compared to that of the cubic phase, clearly demonstrating the crucial role of phase transformation in luminescent performance. This study emphasizes the synergistic optimization of crystal phase and morphology through phase engineering, which substantially improves the upconversion luminescence efficiency of K3GaF6:Er3+, paving the way for further advancements in the design of efficient upconversion materials.

This study presents a multi‐mode X‐ray detection and imaging strategy by integrating photochromism, photoluminescence, and radioluminescence into Tb3+‐doped CaAl2Si2O8. CaAl2Si2O8: Tb3+ exhibits stable radioluminescence, oxygen vacancy‐related photochromism, and photoluminescence modulation, all of which showed a linear relationship with X‐ray exposure. This multi‐mode response enables high‐quality imaging and detection in both bright and dark conditions, facilitating time‐dependent cumulative X‐ray radiation dose assessments. Reversible color and luminescence changes are achieved through cyclic tests involving alternating X‐ray and 473 nm laser irradiation. The PDMS CaAl2Si2O8: Tb3+ ink and flexible film demonstrate high suitability for wearable X‐ray detection devices and imaging of irregular objects, offering an innovative approach to X‐ray detection and imaging. Multi‐mode X‐ray detection and imaging are achieved in CaAl2Si2O8: Tb3+ through photochromism, photoluminescence, and radioluminescence. The material is sensitive to cumulative X‐ray doses, with photochromism and luminescence modulation showing a linear dependence on X‐ray exposure conditions. This makes it suitable for wearable X‐ray detection and imaging of irregular objects.

Photochromic glass shows great promise for 3D optical information encryption and storage applications. The formation of Ag nanoclusters by light irradiation has been a significant development in the field of photochromic glass research. However, extending this approach to other metal nanoclusters remains a challenge. In this study, we present a pioneering method for crafting photochromic glass with reliably adjustable dual‐mode luminescence in both the NIR and visible spectra. This was achieved by leveraging bimetallic clusters of bismuth, resulting in a distinct and novel photochromic glass. When rare‐earth‐doped, bismuth‐based glass is irradiated with a 473 nm laser, and it undergoes a color transformation from yellow to red, accompanied by visible and broad NIR luminescence. This phenomenon is attributed to the formation of laser‐induced (Bi+, Bi0) nanoclusters. We achieved reversible manipulation of the NIR luminescence of these nanoclusters and visible rare‐earth luminescence by alternating exposure to a 473 nm laser and thermal stimulation. Information patterns can be inscribed and erased on a glass surface or in 3D space, and the readout is enabled by modulating visible and NIR luminescence. This study introduces a pioneering strategy for designing photochromic glasses with extensive NIR luminescence and significant potential for applications in high‐capacity information encryption, optical data storage, optical communication, and NIR imaging. The exploration of bimetallic cluster formation in Bi represents a vital contribution to the advancement of multifunctional glass systems with augmented optical functionalities and versatile applications. The research introduces a cutting‐edge optical storage medium, featuring laser‐induced reversible photochromic bismuth‐based glass doped with lanthanide ions, termed ER‐Bi glass. This medium effectively modulates visible and near‐infrared luminescence due to its reversible photochromic properties. The results open new possibilities for using photochromic glass in 3D optical storage and information encryption, showcasing its utility in luminescence modulation.

The effective utilization of solar energy for hydrogen production requires an abundant supply of thermodynamically active photo-electrons; however, the photocatalysts are generally impeded by insufficient light absorption and fast photocarrier recombination. Here, we report a multiple-regulated strategy to capture photons and boost photocarrier dynamics by developing a broadband photocatalyst composed of defect engineered g-C3N4 (DCN) and upconversion NaYF4:Yb3+,Tm3+ (NYF) nanocrystals. Through a precise defect engineering, the S dopants and C vacancies jointly render DCN with defect states to effectively extend the visible light absorption to 590 nm and boost photocarrier separation via a moderate electron-trapping ability, thus facilitating the subsequent re-absorption and utilization of upconverted photons/electrons. Importantly, we found a promoted interfacial charge polarization between DCN and NYF has also been achieved mainly due to Y-N interaction, which further favors the upconverted excited energy transfer from NYF onto DCN as verified both theoretically and experimentally. With a 3D architecture, the NYF@DCN catalyst exhibits a superior solar H2 evolution rate among the reported upconversion-based system, which is 19.3 and 1.5 fold higher than bulk material and DCN, respectively. This work provides an innovative strategy to boost solar utilization by using defect engineering and building up interaction between hetero-materials.

Pleural mesothelioma (PM) is a highly aggressive tumor that is caused by asbestos exposure and lacks effective therapeutic regimens. Current procedures for PM diagnosis are invasive and can take a long time to reach a definitive result. Small extracellular vesicles (sEVs) have been identified as important communicators between tumor cells and their microenvironment via their cargo including circular RNAs (circRNAs). CircRNAs are thermodynamically stable, highly conserved, and have been found to be dysregulated in cancer. This study aimed to identify potential biomarkers for PM diagnosis by investigating the expression of specific circRNA gene pattern (hsa_circ_0007386) in cells and sEVs using digital polymerase chain reaction (dPCR). For this reason, 5 PM, 14 non-PM, and one normal mesothelial cell line were cultured. The sEV was isolated from the cells using the gold standard ultracentrifuge method. The RNA was extracted from both cells and sEVs, cDNA was synthesized, and dPCR was run. Results showed that hsa_circ_0007386 was significantly overexpressed in PM cell lines and sEVs compared to non-PM and normal mesothelial cell lines (p < 0.0001). The upregulation of hsa_circ_0007386 in PM highlights its potential as a diagnostic biomarker. This study underscores the importance and potential of circRNAs and sEVs as cancer diagnostic tools.