Continuous tuning of persistent luminescence wavelength by intermediate-phase engineering in inorganic crystals.

Multicolor tuning of persistent luminescence has been extensively studied by deliberately integrating various luminescent units, known as activators or chromophores, into certain host compounds. However, it remains a formidable challenge to fine-tune the persistent luminescence spectra either in organic materials, such as small molecules, polymers, metal-organic complexes and carbon dots, or in doped inorganic crystals. Herein, we present a strategy to delicately control the persistent luminescence wavelength by engineering sub-bandgap donor-acceptor states in a series of single-phase Ca(Sr)ZnOS crystals. The persistent luminescence emission peak can be quasi-linearly tuned across a broad wavelength range (500-630 nm) as a function of Sr/Ca ratio, achieving a precision down to ~5 nm. Theoretical calculations reveal that the persistent luminescence wavelength fine-tuning stems from constantly lowered donor levels accompanying the modified band structure by Sr alloying. Besides, our experimental results show that these crystals exhibit a high initial luminance of 5.36 cd m-2 at 5 sec after charging and a maximum persistent luminescence duration of 6 h. The superior, color-tunable persistent luminescence enables a rapid, programable patterning technique for high-throughput optical encryption.

Sensitive Luminescence Thermometry through Excitation Intensity Ratio in Eu-Doped BaTiO3.

Optical ratiometric thermometry techniques have gained much attention in recent years due to their reliable and noncontact temperature sensing capability for industrial and biorelated applications. Herein, we exploited the temperature dependence of the absorption band of BaTiO3 (BTO) for novel excitation intensity ratio (EIR) thermometry. Photoluminescence and excitation properties of Eu3+-doped BTO powders were studied as a function of Eu3+ doping concentration. The excitation peak intensities at 397 and 468 nm, corresponding to the 7F0 → 5L6 and 5D2 transitions of Eu3+, were used as EIR parameters. The temperature dependence of the EIR can be explained by the competitive absorption between Eu3+ and the BTO host. The EIR properties were studied in relation to the doping concentration, registering a maximum relative sensitivity (Sr) of 4.89% K-1 in BTO:Eu3+ (0.5%) at 303 K. An amphoteric Eu3+ occupation mode at both Ba2+ and Ti4+ sites was found to interpret the doping concentration dependence of the Sr. The reduced Ba2+ site occupation ratio proved to be responsible for the low Sr values at high Eu3+ doping concentrations. Accordingly, an Eu3+/Ti3+ codoping method was further proposed to improve the Sr by increasing the Ba2+ site occupation ratio. Our result showed that BTO:Eu3+ (0.5%) demonstrated an enhancement of Sr from 4.89 to 6.42% K-1 at 303 K after 2% Ti3+ codoping.

Interfacing Lanthanide Metal-Organic Frameworks with ZnO Nanowires for Alternating Current Electroluminescence.

Alternating current electroluminescence (ACEL) devices are attractive candidates in cost-effective lighting, sensing, and flexible displays due to their uniform luminescence, stable performance, and outstanding deformability. However, ACEL devices have suffered from limited options for the light-emitting layer, which presents a significant constraint in the progress of utilizing ACEL. Herein, a new class of ACEL phosphors based on lanthanide metal-organic frameworks (Ln-MOFs) is devised. A synthesis of lanthanide-benzenetricarboxylate (Ln-BTC) thin film on a brass grid substrate seeded with ZnO nanowires (NWs) as anchors is developed. The as-synthesized Ln-BTC thin film is employed as the emissive layer and shows visible electroluminescence driven by alternating current (2.9 V µm-1 , 1 kHz) for the first time. Mechanistic investigations reveal that the Ln-based ACEL stems from impact excitation by accelerated electrons from ZnO NWs. Fine-tuning of the ACEL color is also demonstrated by controlling the Ln-MOF compositions and introducing an extra ZnS emitting layer. The advances in these optical materials expand the application of ACEL devices in anti-counterfeiting.

Intelligent Colorimetric Indicators for Quality Monitoring and Multilevel Anticounterfeiting with Kinetics-Tunable Fluorescence.

The spoilage and forgery of perishable products such as food, drugs, and vaccines cause serious health hazards and economic loss every year. Developing highly efficient and convenient time-temperature indicators (TTIs) to realize quality monitoring and anticounterfeiting simultaneously is urgent but remains a challenge. To this end, a kind of colorimetric fluorescent TTI, based on CsPbBr3@SiO2 nanoparticles with tunable quenching kinetics, is developed. The kinetics rate of the CsPbBr3-based TTIs is easily regulated by adjusting temperature, concentration of the nanoparticles, and addition of salts, stemming from the cation exchange effect, common-ion effect, and structural damage by water. Typically, when combined with europium complexes, the developed TTIs show an irreversible dynamic change in fluorescent colors from green to red upon increasing temperature and time. Furthermore, a locking encryption system with multiple logics is also realized by combining TTIs with different kinetics. The correct information only appears at specific ranges of time and temperature under UV light and is irreversibly self-erased afterward. The simple and low-cost composition and the ingenious design of kinetics-tunable fluorescence in this work stimulate more insights and inspiration toward intelligent TTIs, especially for high-security anticounterfeiting and quality monitoring, which is really conducive to ensuring food and medicine safety.

Develop a Novel Nomogram to Predict Respiratory Failure in Acute Pancreatitis at Early Stage.

BACKGROUND: Respiratory failure is a common complication in patients suffering from moderately severe or severe acute pancreatitis (AP). The aim of this study was to develop a novel nomogram to predict respiratory failure in AP early. METHODS: Patients, who were hospitalized within 72 hours of AP onset from January 1, 2018, to April 31, 2021 were enrolled in the study. The patients were divided into two groups including respiratory failure group and no respiratory failure group. The demographic characteristics and laboratory parameters were compared between the two groups. A nomogram was established with stepwise logistic regression and "rms" packages of R software. RESULTS: A total of 190 patients were finally included. White blood count, hemoglobin, sodium and calcium were significantly different between the two groups (all p < 0.05). White blood count (odds ratio [OR] = 1.28, 95% confidence interval [CI]: 1.14 - 1.47, p < 0.001), lymphocyte count (OR = 2.92, 95% CI: 1.16 - 7.70, p = 0.023), albumin (OR = 1.15, 95% CI: 1.01 - 1.33, p = 0.045) and calcium (OR = 0.00, 95% CI: 0.00 - 0.01, p < 0.001) were independent risk factors for respiratory failure in AP patients. After stepwise logistic regression was applied, white blood count, albumin, and calcium were used for the construction of the nomogram. The area under the curve (AUC) of the nomogram for respiratory failure was 0.832, which was higher than the BISAP score, and the nomogram possessed high concordance as calibration curves showed. CONCLUSIONS: The nomogram could predict respiratory failure in AP at an early stage with high accuracy.

MicroRNA-21 promotes endometrial carcinoma proliferation and invasion by targeting PTEN.

Endometrial carcinoma is one of the most common gynecological malignant tumors. Recent evidence has demonstrated that miR-21 is involved in the proliferation and invasion of endometrial carcinoma. This study aims to explore the effect of biological behavior of miR-21 on endometrial carcinoma its relationship with PTEN. First, Collected endometrial carcinoma and adjacent non-tumor issues, the relative expression levels of miR-21 and PTEN mRNA were quantitated by real-time polymerase chain reaction (RT-PCR). Next, endometrial carcinoma cell line Ishikawa were transfected with miR-21 inhibitor. After transfection, real-time PCR was used to detect the expression levels of miR-21. Then, the cells proliferation, the apoptotic rates and the invasion rates were detected by MTT method, flow cytometry, and Transwell assay. The expression levels of p-PTEN and PTEN proteins were detected by western blot. The results showed that miR-21 was significantly up-regulation and PTEN was down-regulation in endometrial carcinoma tissues (P < 0.05). miR-21 inhibitor were successfully transfected into Ishikawa cell. The cell proliferation activity, and the number invasion cells in the miR-21 inhibitor group was obviously lower than the miR-21 NC group and Normal group (P < 0.05). The apoptosis rate in the miR-21 inhibitor group was significantly higher than the miR-21 NC group and Normal group (P < 0.05). The expression levels of p-PTEN in miR-21 inhibitor groups were significantly higher than miR-21 NC group and Normal group (P < 0.05). Therefore, we concluded that miR-21 could promote cell proliferation and invasion ability, and inhibite cell apoptosis in endometrial carcinoma partially by regulating its target gene PTEN on post-transcriptional level. In brief, miR-21 may be a new early diagnosis mark and therapy target in endometrial carcinoma.