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Lanthanide luminescence nanothermometers (LNTs) provide microscopic, highly sensitive, and visualizable optical signals for reporting temperature information, which is particularly useful in biomedicine to achieve precise diagnosis and therapy. However, LNTs with efficient emissions at the long-wavelength region of the second and the third near-infrared (NIR-II/III) biological window, which is more favourable for

Objective: To evaluate the effects of different warm-up methods on the acute effect of lower limb explosive strength with the help of a reticulated meta-analysis system and to track the optimal method. Methods: R software combined with Stata software, version 13.0, was used to analyse the outcome metrics of the 35 included papers. Results: 1) Static combined with dynamic stretching [MD = 1.80, 95% CI: (0.43, 3.20)] and dynamic stretching [MD = 1.60, 95% CI: (0.67, 2.60)] were significantly better than controls in terms of improving reverse long jump performance, and the effect of dynamic stretching was influenced by the duration of stretching (I2 = 80.4%), study population (I2 = 77.2%) and age (I2 = 75.6%) as moderating variables, with the most significant effect size for dynamic stretching time of 7-10 min. 2) Only dynamic stretching [MD = -0.08, 95% CI: (-0.15, -0.008)] was significantly better than the control group in terms of improving sprint performance, while static stretching [MD = 0.07, 95% CI: (0.002, 0.13)] showed a significant, negative effect. 3) No results were available to demonstrate a significant difference between other methods, such as foam axis rolling, and the control group. Conclusion: Static stretching was able to reduce explosive performance, while the 2 warm-up methods, namely dynamic stretching and static combined with dynamic stretching, were able to significantly improve explosive performance, with dynamic stretching being the most stable and moderated by multiple variables and dynamic stretching for 7-10 min producing the best explosive performance. In the future, high-quality studies should be added based on strict adherence to test specifications.

Acute inflammation is a basic innate, immediate, and stereotyped immune response to injury, which is characterized by rapid recruitment of immune cells to the vasculature and extravasation into the damaged parenchyma. Visualization of acute inflammation plays an important role in monitoring the disease course and understanding pathogenesis, which lacks specific targeted and observing tools

In the big data era, deep learning technologies have been widely exploited to mine increasingly available traffic data for mobile traffic prediction. Proactive management and optimization of mobile network resources for various wireless services require accurate mobile traffic prediction on different time and spacial scales. However, training deep learning models for different traffic prediction tasks individually is not only time consuming but also sometimes unrealistic as there are not always sufficient historical traffic records available. In this paper, we propose a novel mobile traffic prediction framework based on deep meta-learning (MTPFoDML), which can adaptively learn to learn the proper prediction model for each distinct prediction task from accumulated meta-knowledge of previous prediction tasks. In MTPFoDML, we regard each mobile traffic prediction task as a base-task and adopt a long short-term memory (LSTM) network with a fixed structure as the base-learner for each base-task. By transforming real-world mobile traffic data into the frequency domain, we find that the five main frequency components can characterize the mobile traffic variation over hours, days, and weeks, hence can be used as meta-features of a base-task. We employ a multi-layer perceptron (MLP) as the meta-learner to find the optimal super-parameter value and initial training status for the base-learner of each new base-task according to its meta-features, thus improving the base-learner's prediction accuracy and learning efficiency. Extensive experiments using real-world mobile traffic datasets demonstrate that our framework outperforms the existing prediction models for the same size of base-task training sets. Moreover, while guaranteeing a similar or even better prediction accuracy, meta-learning in MTPFoDML can lead to about 75% and 81%reduction in epoches and base-samples needed to train the base-learners, respectively.

Afterglow materials have become one of the most promising luminescent materials due to their long luminescence lifetime. Photoluminescence quantum yield (PLQY), as one of the most fundamental and essential parameters of luminescent materials, can directly evaluate the luminescence properties of emissive compounds. Recently, a type of afterglow material based on a photochemical reaction has been developed. However, there is no suitable method to measure the PLQY of these afterglow materials due to their special luminescence principle. Herein, we present a method to measure the PLQY for these afterglow materials by collecting the luminescent dynamic curves of emission and excitation light at specific wavelength regions using a commercial spectrometer and an integrating sphere. We found that the emitted photons of this kind of afterglow material are in direct proportion to the excitation time, which means the PLQY is irrelevant to the excitation time.

We demonstrate tunable lifetimes (sub-milliseconds and seconds) at the same emission wavelength of a material, along with an abrupt intensity change between the two emission states. Based on this stepped photon emission material, a time-domain stepwise encoding method is developed and applied to point-of-care testing with an ultra-large quantitative detection range.

Single molecule localization microscopy based on photoactivation is a powerful tool for investigating the ultrastructure of cells. We developed a general strategy for photoactivatable fluorophores, using 2,3-dihydro-1,4-oxathiine group (SO) as a tag to attach to various skeletal structures, including coumarin, BODIPY, rhodamine, and cyanine. The conjugation of SO resulted in a significant loss of fluorescence due to photoinduced electron transfer (PeT). Under the irradiation of excitation light, singlet oxygen generated by the fluorophores converted the SO moiety into its ester derivative, terminated the PeT process, and restored the fluorescence. Single molecule localization imaging was achieved using a dual functional illuminating beam in the visible, acting as both the activating and the exciting source. We successfully applied these photoactivatable probes for time-lapse super-resolution tracking in living cells and super-resolution imaging of microtubule structures in neurons.

Porphyria is a group of genetic photodermatoses that cause too much porphyrin to accumulate in the blood, skin, and liver, resulting in skin photosensitivity and damage, liver disease, or potential liver failure. Conventional detection methods include high-performance liquid chromatography and fluorescence spectrometry. However, these methods usually require complicated pretreatment and time-consuming processes. Therefore, efficient and fast detection of porphyria is urgently needed. Herein, we develop a molecular afterglow reporter-based sensing scheme for the detection of porphyrins in whole blood. The afterglow reporter can respond to the production of singlet oxygen (1O2) of porphyrins after light excitation, and the detection signals can be amplified through adjusting the amount of singlet oxygen and afterglow reporter molecules. Moreover, without the use of a real-time excitation source, afterglow signals can avoid the scattering and autofluorescence interference in biological samples, thereby reducing background noise. More importantly, we prove the applicability of the afterglow reporter in the quantitative detection of porphyrins in whole blood and demonstrate its great clinical potential.

Afterglow materials with long-lived emission after ceasing the excitation source have exhibited tremendous potential for various applications. However, the inherently dim afterglow emission makes i...

Luminescence nanothermometry makes non-invasive and real-time temperature readings possible in living animals. However, the spectral fluctuation in tissues and fluids, as well as the interaction between fluorophores and environment hinders accuracy of the thermometry. Here, we report a luminescence lifetime-based nanothermometry which specifically addresses this problem. A temporal based calibration (lifetime sensing) in the NIR range, an endogenous thermal response as well as a polymer encapsulation evading environmental factors, altogether help to pinpoint temperature in vivo. Thanks to the highly condensed Nd-Yb ions in a well-protected tiny core-shell nanocrystal (overall 11 nm), a temperature sensitivity about 2.07% K−1 (with 5% Yb3+ doped nanoparticles) and an accuracy of 0.27 K (with 25% Yb3+ doped nanoparticles) in biological fluids are achieved. Hopefully, combining thermally activated energy transfer nanothermometer with anti-interference lifetime thermometry would provide a more accurate temperature measurement for biological and preclinical studies.

Bioimaging is a powerful strategy for studying biological activities, which is still limited by the difficulty of distinguishing obscured signals from high background. Despite the development of various new imaging materials and methods, target signals are still likely to be submerged in spontaneous fluorescence or scattering signals. Herein, a novel two-photon excitation-process-based imaging postprocessing algorithm model (2PIA) is introduced to minimize background noise, and triplet-triplet annihilation upconversion metal-organic frameworks (UCMOFs) are chosen as demonstration. Through the collection of several image stacks, the related polynomial of the luminescence intensity and excitation power was established, following splitting the desired signals from noise and obtaining the background-free images definitely. Both in vitro and in vivo experiments show that improved signal visibility is achieved through 2PIA and UCMOFs by removing the interference of scattering, bioluminescence, and other fluorescence materials. The imaging spatial resolution and tissue penetration depth were greatly enhanced. Benefiting from 2PIA, as low as 100 UCMOFs labeled cells can be identified from obscuring background easily after intravenous injection. This image postprocessing method combined with special two-photon excited luminescent materials can conduct biological imaging from complex background interference without using expensive instruments or delicate materials, which holds great promise for accurate biological imaging.

Hypoxia, as a characteristic feature of solid tumors, has a close relationship with tumor resistance to photodynamic therapy (PDT) and chemotherapy. Perfluorocarbon (PFC) is reported to relieve hypoxic in solid tumors by acting as an oxygen carrier via several nanostructures. However, the oxygen delivery process is mostly driven by a concentration gradient, which is uncontrollable. Herein, a photothermally controlled "oxygen bomb" PSPP-Au

Afterglow materials have drawn considerable attention due to their attractive luminescent properties. However, their low-efficiency luminescence in aqueous environment limits their applications in life sciences. Here, we developed a molecular fusion strategy to improve the afterglow efficiency of photochemical afterglow materials. By fusing a cache unit with an emitter, we obtained a blue afterglow system with a quantum yield up to 2.59 %. This is 162 times higher than that achieved with the traditional physical mixing system and more than an order of magnitude larger than that of the covalent coupling system. High-efficiency afterglow nanoparticles were obtained and utilized for bio-imaging with a high signal-to-noise ratio (SNR) of 131, and for the lateral flow immunoassay (LFIA) of β-hCG with a low limit of detection (LOD) of 0.34 mIU mL

Upconversion nanoparticles (UCNPs) and MnO

Lanthanide-ion-doped upconversion materials have been widely used in biological detection, bioimaging, displays, and anticounterfeiting due to their abilities of real-time readings, high spatial resolution, and deep tissue penetration. The typically long fluorescence lifetimes of rare-earth nanoparticles, in the microsecond to millisecond range, make them useful in interference-free lifetime detection imaging. Most detection systems are accompanied by fluorescence resonance energy transfer (FRET), in which the lifetime of the luminescence center can be used as a signal to reveal the degree of FRET. Due to the complex energy level structure and complex energy transfer processes, the apparent lifetimes of upconversion nanoparticles (UCNPs) do not simply equal the decay time of the corresponding energy level, inducing an insignificant lifetime change in the upconversion detection system. In this study, the relationship between the apparent luminescence lifetime of upconversion and the decay rate of each energy level was studied by numerical simulations. It was proved that the apparent lifetime of the emission at 540 nm was mainly affected by the decay rate of Yb

Until now, corona virus disease 2019 (COVID-19) remained to be an enormous threat for global health. As one viral illness induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), versatile, rapid and sensitive method for SARS-CoV-2 detection in early stage is urgently needed. Here, we reported an ultrasensitive and visual in-one-tube detection method which could be accomplished within half an hour from sampling-to-result. By integrating all reactions in one tube, liquid handling steps were omitted and amplicon contamination could be totally avoided. Magnetic beads were employed to achieve the fast extraction of viral nucleic acid and increase the sensitivity. Using portable thermocycler and blue light, the fluorescent results could be directly observed by naked eyes. The proposed method is of higher specificity and sensitivity, nearly at single molecule level. More important, results demonstrated 100% positive detection rate for 40 clinical samples, which was consistent with standard RT-PCR. Thus, our method is considerably simple, rapid, sensitive and accurate, holding great promise for the instant detecting of viruses including SARS-CoV-2 and the next generation of molecular diagnosis.

Lanthanide-doped inorganic upconversion nanocrystals (UCNCs) are promising as fluorescent diagnostic and therapeutic agents for in vivo applications ranging from biological imaging to disease theranostics. However, all currently available lanthanide-doped inorganic UCNCs are not biodegradable and thus cannot be harmlessly eliminated from the body of living organism during a reasonable period of time, making their clinical translations nearly impossible. Here, we report a class of red-emitting biodegradable UCNCs based on Yb3+/Er3+-doped inorganic potassium heptafluozirconate (K3ZrF7:Yb/Er) that features a dynamically "soft" crystal lattice containing water-soluble [ZrF7]3- cluster and a K+ cation. The red-emitting K3ZrF7:Yb/Er UCNCs exhibit a pH-dependent biodegradation capability upon exposure to water both in vitro and in vivo, and the rapid biodegradation rate, monitored using the intrinsic red upconversion luminescence, can be tuned particularly in a mild acidic tumor microenvironment (pH ∼5-6). More importantly, the final biodegradation products of K3ZrF7:Yb/Er UCNCs can be excreted from the body of mice in a short period of time with no evidence of toxicity, in stark contrast to the nondegradable β-NaYF4:Yb/Er UCNCs that primarily accumulate in the main organs of mice. These findings described here unambiguously would benefit the future biomedical applications and clinical translations of lanthanide-doped inorganic UCNCs.

Multiplex detection of microRNAs is highly desirable in trace analysis of clinical samples for early-stage disease diagnosis. In the present study, we report a new liquid suspension nano-chip technology for multiplex detection of microRNAs by detecting side scatter and fluorescence signals of molecular beacon-modified polystyrene nanoparticles, simultaneously. Polystyrene nanoparticles were encoded by distinguished intensity of scattered light with tunable sizes (120 nm, 200 nm and 280 nm). In the proposed detection system, the fluorescence of 5-carboxyfluorescein was recovered due to the structure change of molecular beacons from hairpin to rod-like shape caused by the hybridization of target microRNAs. The well-designed liquid suspension nano-chip system enabled quantitative detection of three colorectal cancer-related microRNAs with low limits of detection and high sensitivity. More importantly, for simulated clinical samples, three random mixed microRNAs were simultaneously detected by accurately decoding the scattering intensity of polystyrene nanoparticles of different sizes and quantitatively analyzed by fluorescence intensity. This technology provides a washing-free, sensitive, convenient and small loading volume strategy for detecting clinical multiplex nucleic acid samples.

Fluorescence sensing has the advantages of being real time, noninvasive, and convenient and having a low impact on the original environment for in vivo detection. Here, a reversible time-gated ratiometric in vivo detection method that could eliminate the interferences from probe amount, photon scattering, and absorption is proposed. Correspondingly, the composite probe must be able to reversibly respond to changes in the microenvironment and emit two luminescence signals at the same working wavelength but different lifetimes. Benefitting from the reversible detection mechanism, the probes could be used to monitor a dynamic biological process and the ratio signal value could be determined only by the concentration of analytes, independent of the probe concentration. Furthermore, benefitting from the same working wavelength, the read-out errors from photon absorption and scattering could be minimized. This method is very suitable for in vivo detection in which the probe distribution and depth are unknown and variable. As a typical model, different pH values in the gastrointestinal area and pH changes caused by drugs and fasting are successfully monitored.

Hormone therapy (HT) is one of the most effective treatments for osteoporosis. However, the nonselective accumulation of hormone in organs such as breast, heart and uterus other than bones causes serious side effects, which impedes the application of HT. Hence, it is critically important to develop a HT strategy with reduced non-specific enrichment of hormone drugs in non-target tissues and enhanced bone-targeting ability. Methods: Herein, a 17β-estradiol (E2)-laden mesoporous silica-coated upconversion nanoparticle with a surface modification of ethylenediaminetetraacetic acid (EDTA) (NaLuF4:Yb,Tm@NaLuF4@mSiO2-EDTA-E2, E2-csUCNP@MSN-EDTA) is developed for bone-targeted osteoporosis hormone therapy. EDTA was attached onto the surface of E2 upconversion nanocomposite to enhance its affinity and efficiency targeting bone tissue and cells to optimize hormone replacement therapy for osteoporosis. We characterized the size, cytotoxicity, loading and release efficiency, in situ and ex vivo imaging. Further, in vitro and in vivo osteogenic ability was tested using preosteoblast and ovariectomy mouse model of osteoporosis. Results: The upconversion core of E2-csUCNP@MSN-EDTA nanoparticle serves as an excellent imaging agent for tracking the loaded hormone drug in vivo. The mesoporous silica layer has a high loading efficiency for E2 and provides a relatively long-lasting drug release within 50 h. EDTA anchored on the silica layer endows the nanocomposite with a bone targeting property. The nanocomposite effectively reverses estrogen deficiency-induced osteoporosis and reduces the damage of hormone to the uterus. The bone mineral density in the nanocomposite treatment group is nearly twice that of the ovariectomized (OVX) group. Compared with the E2 group, the uterine weight and luminal epithelial height were significantly lower in the nanocomposite treatment group. Conclusion: This work demonstrated that E2-csUCNP@MSN-EDTA alleviates the side effect of hormone therapy while maintaining its therapeutic efficacy, which has great potential for developing the next generation of methods for osteoporosis treatment.