Flexible X-Ray Detector for Cumulative Dose Monitoring Through Reversible Photochromism and Luminescence Modulation.

This study presents a multi-mode X-ray detection and imaging strategy by integrating photochromism, photoluminescence, and radioluminescence into Tb-doped CaAlSiO. CaAlSiO: Tb 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.

Luminescence Properties of Bi-Doped GdO Phosphor under UV and X-ray Excitation.

X-ray excited luminescence in scintillators plays a crucial role in applications ranging from medical diagnostics to industrial quality inspection and scientific research. This study explores the potential of Bi-doped GdO phosphors as next-generation scintillators, leveraging their broad-spectrum emission characteristics to achieve higher light yields. We synthesized GdO:Bi phosphors in two crystalline phases─cubic and monoclinic─using a high-temperature solid-phase method.

The relationship between crustal deformation characteristics and strong earthquakes in western China revealed by GNSS.

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.

Small Extracellular Vesicle-Derived Circular RNA hsa_circ_0007386 as a Biomarker for the Diagnosis of Pleural Mesothelioma.

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).

Optical Nonlinearity Enabled Super-Resolved Multiplexing Microscopy.

Optical multiplexing for nanoscale object recognition is of great significance within the intricate domains of biology, medicine, anti-counterfeiting, and microscopic imaging. Traditionally, the multiplexing dimensions of nanoscopy are limited to emission intensity, color, lifetime, and polarization. Here, a novel dimension, optical nonlinearity, is proposed for super-resolved multiplexing microscopy.

Bone disease imaging through the near-infrared-II window.

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.

Precise Defect Engineering on Graphitic Carbon Nitrides for Boosted Solar H Production.

Defect engineering has been regarded as an "all-in-one strategy" to alleviate the insufficient solar utilization in g-CN. However, without appropriate modification, the defect benefits will be partly offset due to the formation of deep localized defect states and deteriorated surface states, lowering the photocarrier separation efficiency. To this end, the defective g-CN is designed with both S dopants and N vacancies via a dual-solvent-assisted synthetic approach.

Metasurface-Controlled Photonic Rashba Effect for Upconversion Photoluminescence.

We demonstrate the effect of spin-momentum locking of upconversion photoluminescence emitted from rare-earth doped nanocrystals coupled to a phase-gradient dielectric metasurface. We observe different directionalities for left and right circular polarized light and associate this experimental observation with realized for upconverted photoluminescence that is manifested in the spin-dependent splitting of emitted light in the momentum space.

Spatiotemporally mapping temperature dynamics of lysosomes and mitochondria using cascade organelle-targeting upconversion nanoparticles.

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.

Multiplexed structured illumination super-resolution imaging with lifetime-engineered upconversion nanoparticles.

The emerging optical multiplexing within nanoscale shows super-capacity in encoding information by using lifetime fingerprints from luminescent nanoparticles. However, the optical diffraction limit compromises the decoding accuracy and throughput of the nanoparticles during conventional widefield imaging. This, in turn, challenges the quality of nanoparticles to afford the modulated excitation condition and further retain the multiplexed optical fingerprints for super-resolution multiplexing.

Controlling the Biological Behaviors of Polymer-Coated Upconverting Nanoparticles by Adjusting the Linker Length of Estrone Ligands.

The estrone ligand is used for modifying nanoparticle surfaces to improve their targeting effect on cancer cell lines. However, to date, there is no common agreement on the ideal linker length to be used for the optimum targeting performance. In this study, we aimed to investigate the impact of poly(poly ethylene glycol methyl ether methacrylate) (PPEGMEMA) linker length on the cellular uptake behavior of polymer-coated upconverting nanoparticles (UCNPs).

High Spatial and Temporal Resolution NIR-IIb Gastrointestinal Imaging in Mice.

Conventional biomedical imaging modalities, including endoscopy, X-rays, and magnetic resonance, are invasive and insufficient in spatial and temporal resolutions for gastrointestinal (GI) tract imaging to guide prognosis and therapy. Here we report a noninvasive method based on lanthanide-doped nanocrystals with ∼1530 nm fluorescence in the near-infrared-IIb window (NIR-IIb, 1500-1700 nm). The rational design of nanocrystals have led to an absolute quantum yield (QY) up to 48.

Stratified Disk Microrobots with Dynamic Maneuverability and Proton-Activatable Luminescence for Imaging.

Microrobots can expand our abilities to access remote, confined, and enclosed spaces. Their potential applications inside our body are obvious, ..

Optical Fingerprint Classification of Single Upconversion Nanoparticles by Deep Learning.

Highly controlled synthesis of upconversion nanoparticles (UCNPs) can be achieved in the heterogeneous design, so that a library of optical properties can be arbitrarily produced by depositing multiple lanthanide ions. Such a control offers the potential in creating nanoscale barcodes carrying high-capacity information. With the increasing creation of optical information, it poses more challenges in decoding them in an accurate, high-throughput, and speedy fashion.

Upconversion nanoparticle-assisted single-molecule assay for detecting circulating antigens of aggressive prostate cancer.

Sensitive and quantitative detection of molecular biomarkers is crucial for the early diagnosis of diseases like metabolic syndrome and cancer. Here we present a single-molecule sandwich immunoassay by imaging the number of single nanoparticles to diagnose aggressive prostate cancer. Our assay employed the photo-stable upconversion nanoparticles (UCNPs) as labels to detect the four types of circulating antigens in blood circulation, including glypican-1 (GPC-1), leptin, osteopontin (OPN), and vascular endothelial growth factor (VEGF), as their serum concentrations indicate aggressive prostate cancer.

Preselectable Optical Fingerprints of Heterogeneous Upconversion Nanoparticles.

The control in optical uniformity of single nanoparticles and tuning their diversity in multiple dimensions, dot to dot, holds the key to unlocking nanoscale applications. Here we report that the entire lifetime profile of the single upconversion nanoparticle (τ profile) can be resolved by confocal, wide-field, and super-resolution microscopy techniques. The advances in both spatial and temporal resolutions push the limit of optical multiplexing from microscale to nanoscale.

Maternal Particulate Matter Exposure Impairs Lung Health and Is Associated with Mitochondrial Damage.

Relatively little is known about the transgenerational effects of chronic maternal exposure to low-level traffic-related air pollution (TRAP) on the offspring lung health, nor are the effects of removing such exposure before pregnancy. Female BALB/c mice were exposed to PM (PM 5 µg/day) for 6 weeks before mating and during gestation and lactation; in a subgroup, PM was removed when mating started to model mothers moving to cleaner areas during pregnancy to protect their unborn child (Pre-exposure). Lung pathology was characterised in both dams and offspring.

Heterochromatic Nonlinear Optical Responses in Upconversion Nanoparticles for Super-Resolution Nanoscopy.

Point spread function (PSF) engineering by an emitter's response can code higher-spatial-frequency information of an image for microscopy to achieve super-resolution. However, complexed excitation optics or repetitive scans are needed, which explains the issues of low speed, poor stability, and operational complexity associated with the current laser scanning microscopy approaches. Here, the diverse emission responses of upconversion nanoparticles (UCNPs) are reported for super-resolution nanoscopy to improve the imaging quality and speed.

Optical tweezers beyond refractive index mismatch using highly doped upconversion nanoparticles.

Optical tweezers are widely used in materials assembly, characterization, biomechanical force sensing and the in vivo manipulation of cells and organs. The trapping force has primarily been generated through the refractive index mismatch between a trapped object and its surrounding medium. This poses a fundamental challenge for the optical trapping of low-refractive-index nanoscale objects, including nanoparticles and intracellular organelles.

Differential inflammatory and toxic effects in-vitro of wood smoke and traffic-related particulate matter from Sydney, Australia.

Background: It is well known that PM generated by traffic or burning wood is pro-inflammatory and induces various adverse health outcomes in humans. In Sydney, New South Wales, Australia, the main anthropogenic contributors to particulate matter (PM) air pollution are wood combustion heaters, on-road vehicles, and coal-fired power stations. However, the relative toxicity of these local sources has not to date been investigated.

Upconversion Nonlinear Structured Illumination Microscopy.

Video-rate super-resolution imaging through biological tissue can visualize and track biomolecule interplays and transportations inside cellular organisms. Structured illumination microscopy allows for wide-field super resolution observation of biological samples but is limited by the strong extinction of light by biological tissues, which restricts the imaging depth and degrades its imaging resolution. Here we report a photon upconversion scheme using lanthanide-doped nanoparticles for wide-field super-resolution imaging through the biological transparent window, featured by near-infrared and low-irradiance nonlinear structured illumination.

Helix Shape Power-Dependent Properties of Single Upconversion Nanoparticles.

Nonblinking, nonbleaching, and superbright single upconversion nanoparticles have been recently discovered with nonlinear power-dependent properties and can be switchable under dual-beam excitations, which are ideal for super-resolution microscopy, single-molecule tracking, and digital assays. Here, we report that the brightness of Nd-Yb-Er-doped nanoparticles displays a pair of unusual double helix shapes as the function of power densities of 976 and 808 nm excitations. We systemically analyze the power-dependent emission spectra, lifetimes, and power-intensity double-log slopes of single upconversion nanoparticles, which reveal that the dynamic roles of Nd ions in the tridoped nanosystem with underlining electron population pathways are power dependent.

Quantitative Lateral Flow Strip Sensor Using Highly Doped Upconversion Nanoparticles.

Paper-based lateral flow assays, though being low-cost and widely used for rapid in vitro diagnostics, are indicative and do not provide sufficient sensitivity for the detection and quantification of low abundant biomarkers for early stage cancer diagnosis. Here, we design a compact device to create a focused illumination spot with high irradiance, which activates a range of highly doped 50 nm upconversion nanoparticles (UCNPs) to produce orders of magnitude brighter emissions. The device employs a very low-cost laser diode, simplified excitation, and collection optics and permits a mobile phone camera to record the results.

Preparation and upconversion emission modification of crystalline colloidal arrays and rare earth fluoride microcrystal composites.

In this paper, highly ordered crystalline colloidal arrays containing rare earth fluoride microcrystals were fabricated. The upconversion emission property of rare earth fluoride microcrystals in crystalline colloidal arrays was studied and modified. A significant suppression and enhancement of the upconversion emission from the rare earth fluorides can be observed in the regions of the photonic band gap and its band edge, respectively.

[Preparation and up-conversion luminescence properties of Yb3+/Tm3+ co-doped Sb2O4 powder].

The Sb2O4:Yb3+, Tm3+ up-conversion luminescence powder with excellent physical, chemical stability and relative low phonon energy was synthesized by the high temperature solid-state reaction and its up-conversion luminescence property was investigated. Under the 980 nm excitation, infrared and blue up-conversion emissions centered at 800 and 480 nm were observed, which were assigned to the 1G4-->3H6 and 3H4-->3 He transitions of Tm2+, respectively. The influence of Yb3+ and Tm3+ concentration on the up-conversion emission property was also obtained.