Optical fiber sensor based on upconversion luminescence for synchronous temperature and curvature sensing.

A multifunctional optical fiber sensor based upconversion luminescence (UCL) for synchronous temperature and curvature sensing was proposed. The sensor was fabricated by assembling UCL nanoparticles doped by rare earth (RE) ions in polydimethylsiloxane (PDMS) materials. Temperature measurements were achieved through the fluorescent intensity ratio (FIR) technique with the dual green UC luminescence generated. The fabricated sensor provided the temperature sensitivity of 714.82 K-1 with excellent linearity (R2=0.997) at a temperature range of 303 to 423 K. In the lower temperature region, temperature measurement based on the FIR technology is almost independent on the fluorescence intensity of a 525 nm emission peak. Hence, deformation produced by the sensor through bending results in detectable and reversible changes in its reflected light, allowing the curvature to be simultaneously measured. The sensor can monitor temperature and curvature simultaneously, providing a new optical alternative for multi-parameters monitoring in the future.

Enhanced core-shell CeO2:Er,Yb@W18O49 heterojunction H2 generation by multiband emissions of Er ions.

The core-shell CeO2:Er,Yb@W18O49 heterojunction is successfully synthesized via the facile solvothermal method. The octahedral CeO2:Er,Yb nanocrystal's core exhibits green (2H11/2, 4S3/2 â†’ 4I15/2), red (4F9/2 â†’ 4I15/2) and NIR (4I11/2 â†’ 4I15/2 and 4I13/2 â†’ 4I15/2) emission under 980 nm laser diode excitation, and the multiband emissions are absorbed by the W18O49 nanowire's shell, re-exciting its higher energy localized surface plasmon resonances (LSPR). With the excitation of 980 nm, the photocatalytic property of CeO2:Er,Yb@W18O49 for hydrogen (H2) evolution from ammonia borane (BH3NH3), a three-fold increase compared to W18O49, is researched. The application of natural sunlight for the production of H2 is studied, and an obvious H2 production enhancement compared to the use of W18O49 (two-fold) is also observed. This remarkable enhancement in the catalytic activity of CeO2:Er,Yb@W18O49 heterostructures is ascribed to the re-excitation of LSPR by multiband emissions of CeO2:Er,Yb.

Heat Stability and Icing Delay on Superhydrophobic Coatings in Facile One Step.

Superhydrophobic coatings are limited to poor durability and a tedious preparation process. In this work, an efficient, eco-friendly, and cost-effective sol-gel method is developed for preparing superhydrophobic surfaces using an all-in-one suspension composed of methyltrimethoxysilane (MTMS), nano silicon dioxide (SiO2) particles, and micron zinc oxide (ZnO) particles. Superhydrophobic coatings with a contact angle (CA) up to 153.9° and a sliding angle (SA) of about 3.0° are prepared on Q235 steel substrates using MTMS 5 mL, 0.8 g of nano SiO2, and 0.2 g of micron ZnO. The morphology of the superhydrophobic coating is characterized by scanning electron microscopy (SEM), and the surface is covered with a micro- and nano-scaled hierarchical rough structure. A series of tests are conducted, including long-term stability tests and thermostability tests. The CAs are all above 150°, and the SAs are below 6.3°, indicating the excellent static stability of the prepared superhydrophobic coatings. Moreover, the CA of the superhydrophobic coating remains above 152° after 120 h of UV exposure, and the time for a water droplet to freeze on the surface of the superhydrophobic coating is 18 times of the bare Q235 steel, indicating that the superhydrophobic coating exhibits good resistance to UV radiation and icing-delay properties.

Aligned Plasmonic Antenna and Upconversion Nanoparticles toward Polarization-Sensitive Narrowband Photodetection and Imaging at 1550 nm.

Lanthanide-doped upconversion nanoparticles (UCNPs) are rising as prospect nanomaterials for constructing polarization-sensitive narrowband near-infrared (NIR) photodetectors (PDs), which have attracted significant interest in astronomy, object identification, and remote sensing. However, polarized narrowband NIR photodetection and imaging based on UCNPs have yet to be realized. Herein, we demonstrate that NIR photodetection and imaging are capable of sensing polarized light as well as affording wavelength-selective detection at 1550 nm by integrating directional-Au@Ag nanorods (D-Au@Ag NRs) with NaYF4:Er3+@NaYF4 UCNPs. Monolayer and large-area D-Au@Ag NRs polarization-sensitive plasmonic antenna films are obtained, and the center of their localized surface plasmon resonance (LSPR) peak is located at around 1550 nm. Experimental and theoretical results reveal that D-Au@Ag NRs have a sharp localized LSPR peak with a dominant scattering cross section. The UCNPs coupled with D-Au@Ag NRs exhibit significantly enhanced and strongly polarization-dependent luminescence with a high degree of polarization (DOP) of 0.72. The first polarization-resolved UC narrowband PD at 1550 nm is achieved, which delivers a DOP of 0.63, a detectivity of 1.69 × 1010 Jones, and a responsivity of 0.32 A/W. Finally, we develop a polarized imaging system for 1550 nm with visual photoelectric detection based on the aforementioned PDs. Our work opens up possibilities for manipulating UC and developing next-generation polarization-sensitive narrowband infrared photodetection and imaging technology.

Exploring the mechanism of action of Sanzi formula in intervening colorectal adenoma by targeting intestinal flora and intestinal metabolism.

Background: Sanzi formula (SZF) is a kind of Chinese herbal compound that has a certain effect on the prevention and treatment of colorectal adenoma (CRA), which can prevent and control the process of CRA-cancer transformation. In this study, we explored the mechanism of action of SZF in anti-CRA using 16S rRNA sequencing and metabolomics technology. Methods: Mice were randomly divided into three groups: Control group, Apcmin/+ model group, and SZF treatment group. Except for the Control group, which used C57BL/6 J mice, the remaining two groups used Apcmin/+ mice. The Control group and Apcmin/+ model group were treated with ultrapure water by gavage, while the SZF treatment group was treated with SZF for 12 weeks. During this period, the physical changes of mice in each group were observed. The gut microbiota was determined by high-throughput sequencing of the 16S rRNA gene, and LC-ESI-MS/MS was used for colorectal metabolomics analysis. Results: Sequencing of the 16S rRNA gut flora yielded 10,256 operational taxonomic units and metabolomic analysis obtained a total of 366 differential metabolites. The intestinal flora analysis showed that SZF could improve intestinal flora disorders in Apcmin/+ mice. For instance, beneficial bacteria such as Gastranaerophilales significantly increased and harmful bacteria such as Angelakisella, Dubosiella, Muribaculum, and Erysipelotrichaceae UCG-003 substantially decreased after the SZF intervention. In addition, metabolomic data analysis demonstrated that SZF also improved the colorectal metabolic profile of Apcmin/+ mice. In Apcmin/+ mice, metabolites such as Anserine and Ectoine were typically increased after SZF intervention; in contrast, metabolites such as Taurocholic acid, Taurochenodesoxycholic acid, Hyocholic acid, Cholic acid, and Tauro-alpha-muricholic acid showed noteworthy reductions. Metabolic flora association analysis indicated that 13 differential flora and 11 differential metabolites were associated. Conclusion: SZF affects the abundance of specific intestinal flora and regulates intestinal flora disorders, improves colorectal-specific metabolites, and ameliorates intestinal metabolic disorders to prevent and treat CRA. Furthermore, the application of intestinal flora and colorectal metabolomics association analysis offers new strategies to reveal the mechanism of action of herbal medicines for the treatment of intestinal diseases.

Network pharmacology analysis on mechanism of Jian Pi Qing Gan Yin decoction ameliorating high fat diet-induced non-alcoholic fatty liver disease and validated in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Jian Pi Qing Gan Yin (JPQGY) has been used clinically to relieve non-alcoholic fatty liver disease (NAFLD) in China for decades; however, the underlying mechanisms of JPQGY remain unclear. AIM OF THE STUDY: We evaluated the effects and mechanisms of JPQGY and hepatic steatosis caused by the middle stage of 13-week-high-fat-diet-induced NAFLD in mice. MATERIALS AND METHODS: Different dosages of JPQGY (5.5, 11, and 22 g/kg/day) were administered to NAFLD mice simultaneously. Body weight, body mass index (BMI), and liver lipid- and inflammation-related serum indicators were measured enzymatically. Liver samples were stained with Oil Red O and hematoxylin and eosin (H&E). Next, we performed a network pharmacology analysis and verified eight target genes mapping to NAFLD-related lipid metabolism pathways. The mRNA/protein expression was analyzed by real-time polymerase chain reaction (PCR) and western blotting. RESULTS: JPQGY significantly relieved histological damage (steatosis-inflammation-fibrosis), prevented the downregulation of AMPK and Pparα, and upregulated LXRα, Srebp-1c, F4/80, Nf-κb, and Cyp2e1 in the HFD-induced NAFLD mouse model. CONCLUSIONS: The present results suggest that chronic treatment with JPQGY ameliorated HFD-induced NAFLD in mice by targeting the first and second phases of hepatic steatosis by stimulating the AMPK/PPARα pathway and inhibiting the LXRα/Srebp1/Nf-κb pathway. Our findings provide evidence that supports the clinical use of this formula for high-fat diet-induced fatty liver disease.

Effects of probiotics on nonalcoholic fatty liver disease: a systematic review and meta-analysis.

OBJECTIVES: Several studies have suggested that the gut-liver axis is closely related to nonalcoholic fatty liver disease (NAFLD). This study was designed to conduct a meta-analysis based on a randomized controlled trial (RCT) to systematically evaluate the efficacy of probiotics in the treatment of NAFLD. METHODS: This study carried out a literature search of published scientific data (up to April 2021) on probiotic therapies of NAFLD. The quality of the included literature was evaluated, and the corresponding data were extracted using the RevMan5.4 software. RESULTS: A total of 9 randomized clinical trials involving 352 patients with NAFLD were included in this study. Results of the meta-analysisstudy showed that probiotic therapy group have significant reduction in the levels of serum indices: alanine aminotransferase (ALT), aspartate transaminase (AST) and total cholesterol (TC) in comparison with the control group. Probiotic therapy was not associated with changes in body mass index (BMI) homeostasis model assessment of insulin resistance (HOMA-IR) and tumor necrosis factor (TNF) Subgroup analyses of BMI indicated that three or more composite probiotics or probiotic treatment for more than three months can significantly reduce the BMI level. CONCLUSION: This systematic review and meta-analysis demonstrated that modulating gut microbiota may be utilized as an effective method to improve liver function and reduce blood lipid levels in patients with NAFLD.

Energy transfer from Er to Nd ions by the thermal effect and promotion of the photocatalysis of the NaYF4:Yb,Er,Nd/W18O49 heterostructure.

The NaYF4:Yb,Er/W18O49 heterostructure is an excellent photocatalyst that can promote H2 evolution by hydrolyzing BH3NH3 under near-infrared (NIR) light irradiation. At the same time, the photothermal effect can be produced in photocatalytic reactions, which will cause the luminescence efficiency and photocatalytic activity to decrease. Determining how to take advantage of that photothermal effect becomes a major problem. Moreover, the energy transfer (ET) process from Er ions to Nd ions in NaYF4 co-doped with Yb/Er/Nd ions (NaYF4:Yb,Er,Nd) occurred at high temperature. Herein, the NaYF4:Yb,Er,Nd/W18O49 quasi-core-shell heterostructure was designed to achieve better H2 production capacity; this heterostructure exhibits a 1.5-fold enhancement of photocatalytic activity for H2 evolution as compared with the NaYF4:Yb,Er/W18O49 heterostructure. This study provides a new way to explore the catalytic activities in the NIR field for application in the development of a sustainable energy source.

Exploration of Unconventional excitation wavelength and dynamic emission in rare-earth doped multilayer core-shell Structures: Application for optical "Hard" and "Soft" switching.

Optical switches are increasingly acknowledged for their potential advantages over mechanical counterparts in various domains. However, research on optical switches remains relatively nascent, primarily focusing on applications like anti-counterfeiting, switching chemical reactions, etc., while neglecting the control of photocurrent switching. Here, we have developed NaYF4:30 %Er-NaYF4-NaYF4:20 %Ho-NaYF4 core-shell nanocrystals with unique upconversion (UC) multi-color emission properties under 1530 nm, 980 nm and 1150 nm laser excitations. These nanocrystals allow for optical control of circuit switching by modulating photocurrent signals in photosensitive circuits. The UC emission is due to the self-sensitization of rare earth ions in the core and shell. By adjusting the intermediate shell thickness, we have optimized the luminescence and investigated the mechanism. Combining these nanocrystals with a WO3 quantum dots (QDs) photochromic hydrogel, dynamic variation of UC emissions could be realized. Moreover, by combining with a commercial silicon photodetector, we constructed a photosensitive circuit demonstrating the modulation of photocurrent signal output and realized the "hard switching" of rapid circuit cutoff. Furthermore, by using the photochromic effect of WO3 QDs, the "soft switching" of slow circuit cutoff and recovery were also achieved. This work has significant implications for the development and application such as energy management system and smart home of optical switches in various fields.