Publications by authors named "Yifeng Lan"

Osteoporosis is a significant health concern. While multiple techniques have been utilized to diagnose this condition, certain limitations still persist. Raman spectroscopy has shown promise in predicting bone strength in animal models, but its application to humans requires further investigation.

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Purpose: Intravenous thrombolysis has emerged as an effective approach to improve the long-term survival and functional status of patients with ischemic stroke. The aim of this study was to assess the impact of a national stroke project on the door-to-needle-time (DNT).

Patients And Methods: The patients were divided into pre-construction and construction periods.

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Adenosine triphosphate (ATP) has an irreplaceable role in the maintenance of many physiological processes and biological functions, and can be employed as an indicator of many diseases. In this work, we constructed a simple and sensitive dual-signal fluorescence aptasensing system for ATP detection with berberine as the signal reporter, ATP-aptamer as the recognition unit and MoS nanosheets as the signal amplification. In the absence of ATP, berberine can bind to the single-stranded DNA (ssDNA) of ATP-aptamer and selectively assemble on the surface of MoS nanosheets, leading to the fluorescence quenching of bererbine based on the fluorescence resonance energy transfer, denoted by "OFF".

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Objective: To investigate DNA methylation (DNAm) status of dickkopf-associated protein 1 (DKK-1) in ossified hip capsule synovium and serum among patients with ankylosing spondylitis (AS).

Methods: Western blot was applied to detect the level of DKK-1 protein expression in hip joint capsule tissues from four patients with AS as well as four patients with femoral neck fracture (FNF) caused by trauma as control. DKK-1 gene promoter methylation (GPM) was examined by methylation-specific polymerase chain reaction.

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Solution-processable all-inorganic CsPbIBr perovskite holds great potential for pure red light-emitting diodes. However, the widely existing defects in this mixed halide perovskite markedly limit the efficiency and stability of present light-emitting diode devices. We here identify that intragrain Ruddlesden-Popper planar defects are primary forms of such defects in the CsPbIBr thin film owing to the lattice strain caused by inhomogeneous halogen ion distribution.

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Thermochromic phosphors are intriguing materials for realizing thermochromic behaviors of light-emitting diodes. Here a highly luminescent and stable thermochromic phosphor based on one-dimensional Cu I (4-dimethylamino-1-ethylpyridinium) is reported. This unique ionic copper-iodine chain-based hybrid exhibits near-unity photoluminescence efficiency owing to the through-space charge-transfer character of relevant electronic transitions.

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All-inorganic CsPbI perovskite is attractive for deep-red light-emitting diodes (LEDs) because of its excellent carrier mobility, high color purity, and solution processability. However, the high phase transition energy barrier of optically active CsPbI black phase hinders the fabrication of efficient and bright LEDs. Here, we report a novel α-BaF nanoparticle substrate-promoted solution-processable heteroepitaxial growth to overcome this hindrance and obtain high-quality optically active γ-CsPbI thin films, achieving efficient and bright deep-red LEDs.

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DNA-based molecular logic gates have been developed rapidly but most of them have a single output mode. This study is to develop a triple-output label-free fluorescent DNA-based multifunctional molecular logic gate with berberine as a fluorescent signal and a Ag-aptamer as a recognition matrix. The Ag-aptamer has been identified to switch from a random coil to an i-motif structure of C-Ag-C from a Ag-induced responsive conformational change.

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Lead halide perovskite nanocrystals (PNCs) are emerging as promising light emitters to be actively explored for high color purity and efficient light-emitting diodes. However, the most reported lead halide perovskite nanocrystal light-emitting diodes (PNCLEDs) encountered issues of emission line width broadening and operation voltage elevating caused by the quantum confinement effect. Here, we report a new type of PNCLED using large-size CsPbBr PNCs overly exceeding the Bohr exciton diameter, achieving ultranarrow emission line width and rapid brightness rise around the turn-on voltage.

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Metal halide perovskites are promising semiconductors for next-generation light-emitting diodes (LEDs) due to their high luminance, excellent color purity, and handily tunable band gap. However, it remains a great challenge to develop perovskite LEDs (PeLEDs) with pure red emission at the wavelength of 630 nm. Herein, we report a spectrally stable and efficient pure red PeLED by employing sequential ligand post-treated CsPbI quantum dots (QDs).

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Based on the specific interaction of Ag and cytosine-cytosine (C-C) base mismatch and using berberine (Ber) as the fluorescent probe and Exonuclease I (Exo I) as the background fluorescence reducing tool, a label-free Exo I-assisted fluorescence aptamer sensing platform was established for the detection of silver ions with high sensitivity and selectivity. Exo I reduced the fluorescence background of the Ber/Ag-aptamer complex to a level similar to that of Ber itself in the absence of Ag. After introducing Ag into the sensing system, it induces the aptamer rich in base C to form C-Ag-C i-motif structure which are resistant to degradation mediated by Exo I.

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All-inorganic cesium lead halide perovskite colloidal nanocrystals are attractive for next-generation light-emitting diodes because of their high color purity, but the nonradiative Auger recombination in perovskite nanocrystal film limits the efficiency and brightness of the fabricated devices. Here, we introduce a surface-engineering process to exchange the original long-chain oleic acid/oleylamine ligands by the cerium-tributylphosphine oxide hybrid ligands to suppress nonradiative Auger recombination in CsPbBr NC film for bright and low-efficiency roll-off light-emitting diodes. Using ultrafast transient absorption and time-resolved photoluminescence spectroscopy, we demonstrate that the hybrid ligand passivation can efficiently remove surface trap states to enhance radiative recombination and homogenize the exciton concentration to suppress nonradiative Auger recombination in the CsPbBr nanocrystal thin film.

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A fluorescence aptasensor for the highly specific and sensitive determination of tetrodotoxin was established with tetrodotoxin-aptamer as the recognition unit, berberine as the signal reporter and exonuclease I as the elimination agent for the background. Berberine has a weak fluorescence emission at 540 nm, and it can form the tetrodotoxin-aptamer/berberine complex, resulted in an increased fluorescence. After introducing exonuclease I, it can degrade the single strand oligonucleotides of tetrodotoxin-aptamer into the single nucleotide in the absence of tetrodotoxin, which lead to dramatic fluorescence quenching, and reduce the background signal of sensing system.

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All-inorganic lead halide perovskite nanocrystals (NCs) are potential candidates for fabricating high-performance light-emitting diodes (LEDs) owing to their precisely tunable bandgaps, high photoluminescence (PL) efficiency, and excellent color purities. However, the performance of pure red (630-640 nm) all-inorganic perovskite LEDs is still limited by the halide segregation-induced instability of the electroluminescence (EL) of mixed halide CsPbIBr NCs. Herein, we report an effective approach to improving the EL stability of pure red all-inorganic CsPbIBr NC-based LEDs via the passivation of potassium bromide on NCs.

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Tetrodotoxin (TTX) specifically can bind to its nucleic acid aptamer (TTX-aptamer) and cause the conformation of TTX-aptamer to be switched from the single-strand random coiling form to the compact neck ring structure. Based on the microenvironment difference of the fluorescence reporter, berberine in between the single-stranded coil oligonucleotides and the structure of the neck ring, a simple, rapid and sensitive label-free fluorescence aptamer sensing system for detection of TTX was developed. Various factors affecting the analysis of TTX were optimized, including the concentration of berberine, ion strength, pH, reaction time, the concentration of TTX-aptamer.

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A label-free fluorescent aptasensing platform was fabricated and a simple and rapid method to detect Hg ion in aqueous solution was put forward by means of berberine and Hg ion-aptamer are as the fluorescence probe and the recognition element, respectively. Various factors including the concentration of berberine, Hg ion and Hg ion-aptamer, pH effect and the reaction time were investigated in detail. Under the optimal experimental conditions, in the sensing system, the fluorescence intensity changes displayed a calibration response for Hg ion in the range of 0.

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Bipolar disorder (BD) affects a significant proportion of Taiwanese individuals (Weissman et al., 1996; Yang, Yeh, & Hwu, 2012). Psychotropic medications are typically the mainstay of treatment for BD, and there is an abundance of international research on biological etiology and medication options.

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