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As the capacity of renewable power plants connected to the grid increases year by year， optimizing the control strategies for their converters becomes crucial for enhancing system stability. Currently， the primary control strategies in renewable power plants focus on grid-following （GFL） and grid-forming （GFM） converters. The former tends to exhibit poor stability in weak grids， while the latter may lose stability in strong grids. To address this challenge， the paper first proposes a hybrid synchronous control structure for grid-connected converters that incorporates adaptive coefficients. This structure combines the phase-locked loop （PLL） commonly used by GFL converters with the power-synchronization loop （PSL） utilized by GFM converters， creating a hybrid synchronous control loop through a proportional coefficient. Subsequently， the corresponding small-signal model is developed， and based on the analysis results of small-signal stability， a method for determining adaptive parameter values is introduced. Finally， simulation results validate that the converter-connected system employing adaptive hybrid synchronous control maintains good stability in weak grids with a short-circuit ratio of 1 and in strong grids with a short-circuit ratio of 30. This provides a new control scheme suitable for the stable operation of grid-connected converters in renewable power plants under varying grid conditions.

Traditional silica-based optical fiber strain sensors suffer from a limited range of strain detection, mismatched mechanical performance, and complicated sensing structures that hinder their practical applications involving complex strain patterns and large strain measurement. To solve these issues, the development of novel flexible optical fiber strain sensors with distributed and multimodal strain sensing performance is critical but challenging. In this work, a flexible hydrogel optical fiber with a step-index core/cladding structure was successfully designed and fabricated using a simple thermal polymerization method involving calcium alginate and polyacrylamide. The resulting flexible fiber exhibited a large stretch deformation capacity and good optical transmission property as well as an effective and reversible strain response. Significantly, a flexible hydrogel functional fiber was further constructed by doping quantum dots with different fluorescent emission wavelengths in different positions. By exploiting a combination of emission wavelength encoding and transmission loss, the assembled flexible hydrogel functional optical fibers could distinguish and recognize the locations, magnitudes, and modes (stretch or bend) of mechanical deformation through a single wavelength of visible light (365 nm) excitation. An ultra-large dynamic range (0–120%) of axial strain and bending deformation (10°–80°) could be effectively detected. This work offers a versatile solution to develop promising stretchable and distributed fiber strain sensors. [ABSTRACT FROM AUTHOR]

Compared to static anti-counterfeiting, polymorphic dynamic anti-counterfeiting typically incorporates additional parameters specifically to increase the complexity of decryption. The development of security in flexible multi-dimensional materials holds significant implications for anti-counterfeiting applications in pharmaceuticals, food, and other products, yet it presents considerable challenges. Here, we propose a composite hydrogel film based on cholesteric liquid crystal (CLC) microspheres with photochromic spiropyran (SP) dyes and sodium alginate/N-isopropyl acrylamide. The film incorporates microspheres capable of synergistic color changes under light/heat stimuli. In the temperature range of 30–12 °C, CLC microspheres can achieve color tuning in the entire visible light band. By incorporating SP, the liquid crystal structural color can overlap with SP fluorescence/dye color. Furthermore, as a soft actuator, the flexible composite hydrogel can achieve a range of predesigned dynamic actuation effects such as biomimetic butterflies and flowers. By integrating the CLC microspheres with actuatable composite hydrogels, a sophisticated multidimensional dynamic anti-counterfeiting flexible label has been successfully realized. This not only enhances security and complexity in multidimensional dynamic anti-counterfeiting but also holds significant potential for applications in dynamic camouflage, bio-inspired actuation, and display sensing. [ABSTRACT FROM AUTHOR]

Chalcone (1,3-diaryl-2-propen-1-one) is an α, β-unsaturated ketone that serves as an active constituent or precursor of numerous natural substances, exhibiting a broad spectrum of pharmacological effects. In this study, the classical Claisen–Schmidt condensation method was used to synthesize the chalcone derivative 2′,4′-dimethoxychalcone (DTC) and evaluate its pharmacological activity. By upregulating the expression of the epithelial cell marker E-cadherin and downregulating the expression of the mesenchymal cell marker vimentin, DTC was found to inhibit transforming growth factor-β1 (TGF-β1)-induced epithelial–mesenchymal transition (EMT) process in A549 cells, maintaining the cells' epithelial-like morphology and reducing the ability of the cells to migrate. Additionally, DTC demonstrated the ability to decrease the expression levels of nitric oxide (NO), tumor necrosis factor (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in RAW264.7 cells, suggesting a possible anti-inflammatory effect. Furthermore, DTC was found to exhibit bacteriostatic activity against Staphylococcus aureus (S. aureus), Proteus vulgaris (P. vulgaris), methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans (C. albicans), indicating that this chemical may possess broad-spectrum antibacterial activity. [ABSTRACT FROM AUTHOR]

Pulmonary fibrosis (PF) is a disease characterised by diffuse nonspecific alveolar inflammation with interstitial fibrosis, which clinically manifests as dyspnoea and a significant decline in lung function. Many studies have shown that the epithelial–mesenchymal transition (EMT) plays a pivotal role in the pathogenesis of pulmonary fibrosis. Based on our previous findings, hypericin (Hyp) can effectively inhibit the process of the EMT to attenuate lung fibrosis. Therefore, a series of hyperoside derivatives were synthesised via modifying the structure of hyperoside, and subsequently evaluated for A549 cytotoxicity. Among these, the pre-screening of eight derivatives inhibits the EMT. In this study, we evaluated the efficacy of Z6, the most promising hyperoside derivative, in reversing TGF-β1-induced EMTs and inhibiting the EMT-associated migration of A549 cells. After the treatment of A549 cells with Z6 for 48 h, RT-qPCR and Western blot results showed that Z6 inhibited TGF-β1-induced EMTs in epithelial cells by supressing morphological changes in A549 cells, up-regulating E-cadherin (p < 0.01, p < 0.001), and down-regulating Vimentin (p < 0.01, p < 0.001). This treatment significantly reduced the mobility of transforming growth factor β1 (TGF-β1)-stimulated cells (p < 0.001) as assessed by wound closure, while increasing the adhesion rate of A549 cells (p < 0.001). In conclusion, our results suggest that hyperoside derivatives, especially compound Z6, are promising as potential lead compounds for treating pulmonary fibrosis, and therefore deserve further investigation. [ABSTRACT FROM AUTHOR]

The electrocatalytic CO2 reduction reaction (CO2RR) offers a fascinating approach to converting CO2 into valuable chemical feedstocks. Up to now, the development of highly efficient electrocatalysts has been a significant bottleneck in this field. In this study, employing density functional theory (DFT) calculations, we design a range of stable two-dimensional (2D) metalloporphyrin organic frameworks (TM-PMOFs, TM = Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, and Ag, respectively) built by copper clusters and metalloporphyrin (TM-TCPP), whose CO2RR performance is studied in detail. Among them, the 2D cobaltporphyrin-based organic framework (Co-PMOF) is identified to be the best CO2RR electrocatalyst on account of its low limiting potential (−0.53 V), whose enhanced electrocatalytic performance can be attributed to the presence of numerous active sites on both sides of its 2D framework, as well as the synergistic effect between copper clusters and cobaltporphyrins in facilitating CO2 reduction. These findings provide valuable insights and encourage further experimental research on metallic 2D PMOF materials for CO2 electrochemical reduction. [ABSTRACT FROM AUTHOR]

Given the diminishing reserves of fossil fuels, the development of renewable alternative energy sources is of global importance. Photocatalytic hydrogen (H 2) evolution stands out as a promising and cost-effective method to harness sunlight for producing carbon-free H 2 fuel. Recently, two-dimensional (2D) covalent organic frameworks (COFs) have garnered considerable research interest in photocatalysis on account of their exceptional surface area and predictable assembly of diverse molecules with adjustable electronic properties. Herein, six 2D COFs are constructed by topologically assembling phosphorus-alkynyl functional moieties and benzene-based building units, including benzene (COF-1), triazine (COF-2), heptazine (COF-3), triphenyl-benzene (COF-4), triphenyl-triazine (COF-5), and triphenyl-heptazine (COF-6), employing first-principles calculations. Our computational results illustrate that the variation of benzene-based building units significantly regulates the electronic structures of COFs, all of which possess semiconductor properties with tunable bandgaps spanning from 1.56 to 2.56 eV. Of particular importance, COF-1, COF-2, COF-4, COF-5, and COF-6 can spontaneously stimulate the hydrogen evolution reaction (HER) under their own light-induced bias without the need for sacrificial agents and co-catalysts. Among them, COF-4 and COF-5 show the best HER activity without light-induced bias, with ΔG values of 0.02 and −0.01 eV, respectively, whose excellent photocatalytic performance can be ascribed to their appropriate electronic band structures, pronounced optical absorption, and low work functions. This finding offers profound insights for exploring other highly efficient HER photocatalysts. Synopsis: Phosphorus-alkynyl COFs (COF-1, 2, 4, 5, 6), featuring varied benzene-based units, can spontaneously initiate HER under light-induced bias, eliminating the reliance on sacrificial agents or co-catalysts. [Display omitted] • The 2D COFs are constructed by phosphorus-alkynyl moieties and benzene-based units. • Varying the benzene-based units notably modulates the electronic structures of COFs. • COF-1, 2, 4, 5, 6 can spontaneously initiate HER under their own light-induced bias. • COF-4, 5 show superior HER activity in the absence of light-induced bias. [ABSTRACT FROM AUTHOR]

Acute-on-chronic liver failure (ACLF) and decompensated cirrhosis (DC) are life-threatening syndromes that can develop at the end-stage of chronic hepatitis B virus (HBV) infection. Both ACLF and DC are complicated by hepatic and extrahepatic pathogeneses. To better understand the compartment-specific metabolic modulations related to their pathogenesis, HBV-DC, HBV-ACLF patients, and controls (30 each) were analyzed by metabolomics using portal (Port), hepatic vein (Hep), and peripheral (Peri) serum. Compartment ratios of metabolites (Ratio Hep/Port , Ratio Peri/Hep , and Ratio Port/Peri ) were calculated. The liver tissues (10 per group) were analyzed using transcriptomics and metabolomics. An additional 75 patients with ACLF, 20 with DC, and 20 with liver cirrhosis (LC) were used to confirm oxlipid dysregulation. Both multi-omics datasets suggest suppressed energy, amino acid, and pyrimidine metabolism in the ACLF/DC liver. The serum metabolomic variations were contributed primarily by disease rather than sampling compartments, as both HBV-ACLF and HBV-DC patients demonstrated abnormal profiles of amino acids and peptides, indoles, purines, steroids, and benzimidazoles. In ACLF/DC patients, impaired hepatic metabolism resulted in a highly correlated hepatic and portal vein serum metabolome and release of inflammatory lipids and heme metabolites from the liver. HBV-ACLF showed higher Ratio Peri/Hep of extrahepatic inflammatory oxlipids, while HBV-DC patients showed higher Ratio Port/Peri of gut microbial metabolites. An inflammatory oxlipid outburst was confirmed in the early stages of HBV-ACLF. The inflammatory effects of the selected oxlipids were confirmed in monocytes. These findings support a synergy between liver-specific mechanisms and systemic inflammation in ACLF/DC development, and that pro-inflammatory oxlipids are metabolic signatures of early HBV-ACLF.

The Yellow River Delta possesses lots of characteristic medicinal plants due to its high salinity and high alkaline environment and Limonium sinense is an iconic plant. However, there are very few studies on L. sinense and its chemical constituents have not been investigated in recent ten years. In the present study, the chemical constituents and bioactivities of L. sinense were fully studied for the first time. UPLC-MS/MS method combined with database comparison identified 109 compounds mainly including flavonoids, alkaloids and polyphenols. In addition, the potential bioactivities of L. sinense were considerated as anti-inflammatory, anti-oxidative, anti-tumor, hepatoprotective and hpyerglycemic activities based on these identified compounds and their related literature. Furthermore, four derivatives of 12-oxo-phytodienoic acid and butenolide including two new ones (1 and 2) were isolated from the whole plants of L. sinense. Their structures, including the absolute configurations, were determined by the analysis of comprehensive spectroscopic data. All isolates were evaluated for their anti-inflammatory activity. Compound 1 exhibited moderate anti-inflammatory activity with IC 50 value of 37.5±1.2 μM on NO production level., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Background: The rapid growth of web-based medical services has highlighted the significance of smart triage systems in helping patients find the most appropriate physicians. However, traditional triage methods often rely on department recommendations and are insufficient to accurately match patients' textual questions with physicians' specialties. Therefore, there is an urgent need to develop algorithms for recommending physicians., Objective: This study aims to develop and validate a patient-physician hybrid recommendation (PPHR) model with response metrics for better triage performance., Methods: A total of 646,383 web-based medical consultation records from the Internet Hospital of the First Affiliated Hospital of Xiamen University were collected. Semantic features representing patients and physicians were developed to identify the set of most similar questions and semantically expand the pool of recommended physician candidates, respectively. The physicians' response rate feature was designed to improve candidate rankings. These 3 characteristics combine to create the PPHR model. Overall, 5 physicians participated in the evaluation of the efficiency of the PPHR model through multiple metrics and questionnaires as well as the performance of Sentence Bidirectional Encoder Representations from Transformers and Doc2Vec in text embedding., Results: The PPHR model reaches the best recommendation performance when the number of recommended physicians is 14. At this point, the model has an F 1 -score of 76.25%, a proportion of high-quality services of 41.05%, and a rating of 3.90. After removing physicians' characteristics and response rates from the PPHR model, the F 1 -score decreased by 12.05%, the proportion of high-quality services fell by 10.87%, the average hit ratio dropped by 1.06%, and the rating declined by 11.43%. According to whether those 5 physicians were recommended by the PPHR model, Sentence Bidirectional Encoder Representations from Transformers achieved an average hit ratio of 88.6%, while Doc2Vec achieved an average hit ratio of 53.4%., Conclusions: The PPHR model uses semantic features and response metrics to enable patients to accurately find the physician who best suits their needs., (©Yingbin Zheng, Yunping Cai, Yiwei Yan, Sai Chen, Kai Gong. Originally published in JMIR Human Factors (https://humanfactors.jmir.org), 15.08.2024.)

Background: After the implementation of 2- and 3-child policies, the rising proportion of high-age and high-risk pregnancies put enormous pressure on maternal and child health (MCH) services for China. This populous nation with an increasing population flow imperatively required the support of large-scale information systems for management. Municipal MCH information systems were commonly applied in developed cities of eastern provinces in China. However, implementation of provincial MCH information systems in relatively low-income areas is lacking. In 2020, the implementation of a regional maternal and child information system (RMCIS) in Inner Mongolia filled this gap., Objective: This paper aimed to demonstrate the construction process and evaluate the implementation effect of an RMCIS in improving the regional MCH in Inner Mongolia., Methods: We conducted a descriptive study for the implementation of an RMCIS in Inner Mongolia. Based on the role analysis and information reporting process, the system architecture design had 10 modules, supporting basic health care services, special case management, health support, and administration and supervision. Five-color management was applied for pregnancy risk stratification. We collected data on the construction cost, key characteristics of patients, and use count of the main services from January 1, 2020, to October 31, 2022, in Inner Mongolia. Descriptive analysis was used to demonstrate the implementation effects of the RMCIS., Results: The construction and implementation of the RMCIS cost CNY 8 million (US $1.1 million), with a duration of 13 months. Between 2020 and 2022, the system recorded 221,772 registered pregnant women, with a 44.75% early pregnancy registry rate and 147,264 newborns, covering 278 hospitals and 225 community health care centers in 12 cities. Five-color management of high-risk pregnancies resulted in 76,975 (45.45%) pregnancies stratified as yellow (general risk), 36,627 (21.63%) as orange (relatively high risk), 156 (0.09%) as red (high risk), and 3888 (2.30%) as purple (infectious disease). A scarred uterus (n=28,159, 36.58%), BMI≥28 (n=14,164, 38.67%), aggressive placenta praevia (n=32, 20.51%), and viral hepatitis (n=1787, 45.96%) were the top factors of high-risk pregnancies (yellow, orange, red, and purple). In addition, 132,079 pregnancies, including 65,018 (49.23%) high-risk pregnancies, were registered in 2022 compared to 32,466 pregnancies, including 21,849 (67.30%) high-risk pregnancies, registered in 2020., Conclusions: The implementation of an RMCIS in Inner Mongolia achieved the provincial MCH data interconnection for basic services and obtained both social and economic benefits, which could provide valuable experience to medical administration departments, practitioners, and medical informatics constructors worldwide., (©Yiwei Yan, Congyan Xing, Jian Chen, Yingbin Zheng, Xiaobin Li, Yirong Liu, Zhanxiang Wang, Kai Gong. Originally published in JMIR Pediatrics and Parenting (https://pediatrics.jmir.org), 25.03.2024.)