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Controlled radical polymerization (CRP) techniques enable the preparation of diverse, chemically tailored polymers with a variety of chain architectures. Separately, light‐mediated polymerization reactions offer a number of advantages over thermal polymerizations in terms of energy efficiency, sustainability, and versatility. Recent work has combined photopolymerization and CRP techniques to advance the synthesis of polymers with nonlinear architectures, including bottlebrush polymers, star polymers, hyperbranched polymers, and cyclic polymers. These photoCRP methods offer novel routes to nonlinear polymers using mild reaction conditions. In this review, we provide an overview of photoCRP techniques for the synthesis of nonlinear polymers. We start with a discussion of photoCRP applied to the synthesis of linear polymers and discuss the underlying reaction mechanisms. Then, we discuss photoCRP applied to the synthesis of bottlebrush, star, hyperbranched, cyclic, and surface‐initiated polymer brushes. For each case, we discuss the synthetic strategy and the unique properties and characteristics of the resulting polymers, and we provide a perspective on potential future directions for research. [ABSTRACT FROM AUTHOR]

Renal interstitial fibrosis (RIF) represents an irreversible and progressive pathological manifestation of chronic renal disease, which ultimately leads to end‐stage renal disease. Long noncoding RNAs (lncRNAs) have been suggested to be involved in the progression of RIF. Small nucleolar RNA host gene 16 (SNHG16), a member of lncRNAs, has been found to be involved in the progression of pulmonary fibrosis. This paper first researched the effect of SNHG16 on renal fibrosis. We established a unilateral ureteral obstruction (UUO)‐induced mouse RIF model by ligation of the left ureter to evaluate the biological function of SNHG16 in RIF. As a result, SNHG16 was upregulated in UUO‐induced renal fibrotic tissues. Knockdown of SNHG16 inhibited RIF and reduced alpha‐smooth muscle actin (α‐SMA), fibronectin, and college IV expression. miR‐205 was a target of SNHG16, and downregulated in UUO‐induced renal fibrotic tissues. Inhibition of miR‐205 promoted RIF and increased the expression of α‐SMA, college IV, and fibronectin. Overexpression of SNHG16 promoted the UUO‐induced RIF, but miR‐205 abrogated this effect of SNHG16. Histone deacetylase 5 (HDAC5) showed high expression in UUO‐induced renal fibrotic tissues. Knockdown of HDAC5 significantly reduced α‐SMA, fibronectin, and college IV expression in renal tissues of UUO‐induced mice. Inhibition of miR‐205 promoted HDAC5 expression, but knockdown of SNHG16 inhibited HDAC5 expression in renal tissues of UUO‐induced mice. In conclusion, SHNG16 is highly expressed in renal fibrotic tissues of UUO‐induced mice. Knockdown of SHNG16 may prevent UUO‐induced RIF by indirectly upregulating HDAC5 via targeting miR‐205. SHNG16 may be novel target for treating renal fibrosis. [ABSTRACT FROM AUTHOR]

Prolonged exposure of the peritoneum to high glucose dialysate leads to the development of peritoneal fibrosis (PF), and apoptosis of peritoneal mesothelial cells (PMCs) is a major cause of PF. The aim of this study is to investigate whether Astragaloside IV could protect PMCs from apoptosis and alleviate PF. PMCs and rats PF models were induced by high glucose peritoneal fluid. We examined the pathology of rat peritoneal tissue by HE staining, the thickness of rat peritoneal tissue by Masson's staining, the number of mitochondria and oxidative stress levels in peritoneal tissue by JC‐1 and DHE fluorescence staining, and mitochondria‐related proteins and apoptosis‐related proteins such as PGC‐1α, NRF1, TFAM, Caspase3, Bcl2 smad2 were measured. We used hoechst staining and flow cytometry to assess the apoptotic rate of PMCs in the PF model, and further validated the observed changes in the expressions of PGC‐1α, NRF1, TFAM, Caspase3, Bcl2 smad2 in PMCs. We further incubated PMCs with MG‐132 (proteasome inhibitor) and Cyclohexylamine (protein synthesis inhibitor). The results demonstrated that Astragaloside IV increased the expression of PGC‐1α by reducing the ubiquitination of PGC‐1α. It was further found that the protective effects of Astragaloside IV on PMCs were blocked when PGC‐1α was inhibited. In conclusion, Astragaloside IV effectively alleviated PF both in vitro and in vivo, possibly by promoting PGC‐1α to enhance mitochondrial synthesis to reduce apoptotic effects. [ABSTRACT FROM AUTHOR]

Abnormal vibration is a direct response to the mechanical defects of electrical equipment, and requires reliable vibration sensing for health condition evaluation in the associated system. The triboelectric nanogenerator (TENG) triggered by random vibration to generate electrical energy/signal while giving feedback on the vibration state, paving a promising way towards self‐powered sensors. Here, an all‐in‐one sensing system configured with a vibration sensor demonstrates instantaneous discharge boosted TENG and IR wireless communication for vibration state online monitoring. The sandwich‐structured TENG combined with mechanical switches can release the co‐accumulated charges from dual triboelectric layers to yield giant instantaneous output power of 616 W, which is 106 times higher than that of the continuous discharge. Moreover, an IR LED as a transmitter driven by the TENG can form an all‐in‐one vibration sensor enabling wireless communication, where the sensor can be further integrated with repeaters and phones to establish a wireless vibration online monitoring system for vibration state visualization. This work presents a novel idea to implement high‐power TENG with IR communication integration for in situ vibration online monitoring. Such a strategy is potentially available for distributed sensor construction towards abnormal signal monitoring that reflects the operating state of equipment. [ABSTRACT FROM AUTHOR]

Phosphorus‐doped boron nitride (PBN) has been confirmed as an effective metal‐free catalyst for the direct dehydrogenation (DDH) of ethylbenzene to styrene. In this paper, we further used barbituric acid as co‐reactant sources to create B defects in both PBN and mesoporous PBN (m‐PBN) materials. The XPS, N2 adsorption‐desorption, UV‐vis DRS, EPR, 11B SS NMR characterizations indicated both the electronic and pore structures of the catalyst with B defects were adjusted. Except for the improvement of mass transfer caused by B defects, DFT calculations showed the increase of electron density in B defects areas could enhance the breaking of C−H in ethylbenzene and the bond‐forming of H−H, which was acted to improve the catalytic activity. The m‐PBN with B defects delivered the styrene production rate of 22.54 mmolST g−1 h−1 and stably run 300 h when in‐situ grown on Al2O3, proving that defect tuning strategy is useful to construct efficient catalysts for styrene production. [ABSTRACT FROM AUTHOR]

Natural wind energy harvesting enables a far‐reaching and sustainable solution to supply pervasive sensors in the Internet of Things (IoT). Electromagnetic generators (EMGs) struggle to harvest energy from breezes, which causes regrettable energy wastage. Herein, a triboelectric‐electromagnetic hybridized nanogenerator (TEHG) is designed with a dual‐rotor structure to consolidate harvesting band for high efficiency of triboelectric nanogenerators (TENGs) in breeze and the EMG in high wind speeds. The TEHG performs an efficient energy collection (41.05 W m−3) and a smooth output in the wind speed of 2−16 m s−1, attributed to the environmental self‐adaptive cooperation between TENGs and EMGs. The TENG output power contribution is more than 70% at low wind speeds (<5 m s−1). Moreover, a dual‐channel power management topology (DcPMT) is established to co‐manage outputs of two modules in TEHG. By virtue of the DcPMT hierarchically combining the isolated storage with undervoltagelockout strategy, the TEHG steadily supplies a standardized 3.3 V voltage for commercial electronics. Furthermore, a TEHG‐based self‐powered system is demonstrated for driving sensors to monitor meteorological information. The TEHG with DcPMT is advantageous in broad‐band and high‐efficiency of wind energy harvesting, thus exhibiting a great potential for elevating the environmental self‐adaptability and stability margin of the IoT. [ABSTRACT FROM AUTHOR]

The cover image is based on the Article Progress in photocontrolled radical polymerization for the synthesis of nonlinear polymer architectures by Dongjoo Lee et al., https://doi.org/10.1002/pol.20230889. [ABSTRACT FROM AUTHOR]

Summary: Flavor‐imparting volatile chemicals accumulate as fruits ripen, making major contributions to taste. The NAC transcription factor nonripening (NAC‐NOR) and DNA demethylase 2 (SlDML2) are essential for tomato fruit ripening, but details of the potential roles and the relationship between these two regulators in the synthesis of volatiles are lacking.Here, we show substantial reductions in fatty acid and carotenoid‐derived volatiles in tomato slnor and sldml2 mutants. An unexpected finding is the redundancy and divergence in volatile profiles, biosynthetic gene expression, and DNA methylation in slnor and sldml2 mutants relative to wild‐type tomato fruit. Reduced transcript levels are accompanied by hypermethylation of promoters, including the NAC‐NOR target gene lipoxygenase (SlLOXC) that is involved in fatty acid‐derived volatile synthesis.Interestingly, NAC‐NOR activates SlDML2 expression by directly binding to its promoter both in vitro and in vivo. Meanwhile, reduced NAC‐NOR expression in the sldml2 mutant is accompanied by hypermethylation of its promoter. These results reveal a relationship between SlDML2‐mediated DNA demethylation and NAC‐NOR during tomato fruit ripening.In addition to providing new insights into the metabolic modulation of flavor volatiles, the outcome of our study contributes to understanding the genetics and control of fruit ripening and quality attributes in tomato. [ABSTRACT FROM AUTHOR]

An agglomeration phenomenon characterized by nanoparticle dispersion is a decisive factor that reflects the degree of the maintained overall performance of nanofluids and other nanocomposites. However, the quantitative characterization and non‐destructive measurement for nanofluid dispersion (NFD) still remain challenged. Herein, an in situ NFD measurement system based on a variable frequency liquid–solid triboelectric nanogenerator (VFLS‐TENG) is developed. This work utilizes VFLS‐TENG as a passive probe and proposes an equivalent capacitance circuit model for detecting NFD based on the electric double layer model at liquid–solid interfaces. In the circuit model, a quantitative calculation process for both particle size and spacing is introduced through parameter identification using the Quantum Genetic and Levenberg–Marquardt hybrid algorithm, and parameter separation using the Runge–Kutta algorithm. The results demonstrates a good agreement with the traditional methods, among which the measured particle size is more accurate than the hydrodynamic diameter of dynamic light scattering by 28.6% with a high sensitivity of 1667 nm nF−1. The proposed method is capable of measuring the effective charge on the nanoparticle surface in situ, and simultaneously obtaining the particle size and spacing for the online monitoring NFD, thus further facilitating the controllable preparation during the nano‐composites modification, and quantitative optimization of nanofluid design performance. [ABSTRACT FROM AUTHOR]

Overhead transmission lines are vulnerable to aeolian vibrations that threaten the operation of the power grid. A triboelectric nanogenerator (TENG) based self‐powered system offers a desirable way for vibration online‐monitoring with potential for large‐scale deployment. In this work, a self‐powered sensor network constructed by active vibration sensor (AVS) units with a spring‐mass based TENG (S‐TENG) is reported for effective energy harvesting and broadband vibration sensing. The basic TENG with structural parameters is first discussed from the aspects of efficiency and response characteristics, then the spring constant and mass weight are also adjusted for S‐TENGs with different optimal operation regions, thus the overall vibration amplitude and frequency response are further enhanced by the mutual compensation of S‐TENGs with a weight allocation strategy. Furthermore, the S‐TENGs are combined with external circuits to compose the AVS units, which are deployed in a distributed manner on a simulated transmission line to demonstrate a self‐powered wireless warning system and an aeolian vibration mapping system, enabling abnormal vibration warnings and vibration distribution monitoring over the whole line. This work represents a novel strategy for utilizing TENG technology for transmission line aeolian vibration monitoring and provides valuable guidance for further sensor network construction and power grid visualization. [ABSTRACT FROM AUTHOR]

There is no information search system can assist young children's known picture book search needs since the information is not organized according to their cognitive abilities and needs. Therefore, this study explored young children's known picture book search strategies and extracted picture book search elements by simulating a search scenario and playing a picture book search game. The study found 29 elements children used to search for known picture books. Then, these elements are classified into three dimensions: The first dimension is the concept category of an element. The second dimension is an element's status in the story. The third dimension indicates where an element appears in a picture book. Additionally, it revealed a young children's general search strategy: Children first use auditory elements that they hear from the adults during reading. After receiving error returns, they add visual elements that they see by themselves in picture books. The findings can not only help to understand young children's known‐item search and reformulation strategies during searching but also provide theoretical support for the development of a picture book information organization schema in the search system. [ABSTRACT FROM AUTHOR]

Electron trap states characterization plays a vital role in mesoscale measurement. Previous destructive methods have been applicable only in qualitative comparison. Nonetheless, the imaging of trap states distribution in space and energy level remains challenging. Herein, a triboelectric nanogenerator driven detrapping current (TENGd‐DTC) measurement system is reported. The triboelectric nanogenerator (TENG) is designed as a high voltage generator, with an output voltage of ≈3 kV for driving the dielectric barrier discharge (DBD). The discharge model with dynamic carriers' evolution is proposed, thus the detrapping currents can be extracted from DBD currents, based on which energy levels and densities of trap states are quantitatively calculated. The chamber design parameters as the platform for TENGd‐DTC measurement under DBD are optimized. With the optimized chamber, the energy level range within 0.6–0.8 eV can be clearly characterized, and the difference between results of the proposed and the current methods is less than 12%. More importantly, the improved measurement electrode array is applied for multi‐point scanning, and imaging of trap parameters is demonstrated vividly at a spatial resolution of ≈50 μm. This work paves an effective and non‐destructive imaging approach for trap states characterization, and potential applications in mesoscale modification of functional materials. [ABSTRACT FROM AUTHOR]

A triboelectric nanogenerator (TENG) based self‐powered system for wind energy harvesting introduces a desirable solution to alleviate the expanding energy supply concerns in the development of the internet of things. In this work, an auto‐switching self‐powered system based on a dual‐rotation shaft TENG (D‐TENG) is reported to effectively harvest wind energy over a broad‐band wind speed (2.2–16 m s−1). The D‐TENG is designed in a concentric dual‐rotation shaft structure, in which two independent TENGs with different shapes, sizes, and arm lengths of wind cups are rationally coupled. The integration of the two TENGs with varied structural parameters achieves mutual compensation of their own merits, enabling the whole system to have preferable aerodynamics and high energy conversion efficiency over a broad range of wind speeds. Moreover, an electromagnetic generator (EMG) with the same energy collection module is also fabricated for a comparison with TENG in the start‐up properties and average output power. Furthermore, a packaged self‐powered system is demonstrated for simulated wind energy harvesting, while the charging characteristics are also discovered. The proposed TENG renders a more efficient technique for energy harvesting and greatly expands its potential in the large‐scale wind energy harvesting that can be attributed to the multi‐stage strategy. [ABSTRACT FROM AUTHOR]

SophoraflavanoneG (SG), an important prenylated flavonoid isolated from Sophoraalopecuroides.L, is effective for many illnesses. The present study was designed to investigate whether the compound could reverse depressive-like symptoms and investigate its possible mechanisms. Chronic Unpredictable Mild Stress (CUMS) mice were treated with fluoxetine and SG. The immobility time in forced swimming test (FST) and tail suspension test (TST) were recorded. The levels of pro-inflammatory cytokines and neurotransmitters in the hippocampus were evaluated. Furthermore, the protein expressions of PI3K, AKT, mTOR, p70S6K, BDNF, and Trkb in hippocampus were detected. Rapamycin, the selective mTOR inhibitor, was used to estimate the potential mechanism. As a result, after 7 days of SG treatment, the immobility time in FST and TST was declined obviously. The levels of IL-6, IL-1β, and TNF-α in the hippocampus were significantly reduced, and the quantity of 5-HT and NE was raised considerably in SG-treated group compared with the CUMS-exposed group. Additionally, SG could up-regulate the expressions of PI3K, AKT, mTOR, 70S6K, BDNF, and Trkb. The blockade of mammalian target of rapamycin signaling blunted the antidepressant effect and reversed the up-regulation of BDNF expression caused by SG. These findings suggested that SG treatment alleviated depressive-like symptoms via mTOR-mediated BDNF/Trkb signaling. [ABSTRACT FROM AUTHOR]

A rather low crystallization rate has greatly limited the application of poly(l‐lactide) (PLLA) in many fields. Thus, functionalized cellulose nanoparticles (CPNs) were prepared based on cellulose aerogel through a novel and simple approach and were then applied as biobased nucleating agents to improve the crystallization rate of PLLA. First, isolated individual CPNs with a mean diameter around 37.2 nm and regular circular shape were obtained. Subsequently, PLLA based nanocomposites with various contents of CPNs were prepared by solution blending. As a result, CPNs promoted the crystallization rate of PLLA significantly. Compared with that of neat PLLA, the crystallinity (Xc) of the nanocomposites increased dramatically more than 30 times to 36.65% at a CPN loading of 0.5 wt%, and the half‐crystal time (t1/2) at 130 °C decreased by about 91%. Furthermore, due to the presence of CPNs, which provided a large number of nucleation sites in the PLLA matrix, the chain conformational and crystallization kinetics behavior of the PLLA based nanocomposites during isothermal crystallization were changed in the early stages, and based on this result a proposal for the nucleation process for CPNs in a PLLA matrix is presented. © 2018 Society of Chemical Industry The schematic diagram represents the preparation of functionalized cellulose nanoparticles and their effect on the crystallization behavior of poly(l‐lactide) matrix. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Different parts of Sophora alopecuroides L. (Fabaceae) have historically been used in traditional Chinese medicine for the treatment of dysentery and enteritis. This plant is also utilised as an important resource for industrial preparation of quinolizidine alkaloidal pharmaceuticals. Objective: Establish a reliable, simple and fast analytical method for the quantitative determination of the quinolizidine‐type alkaloids and extend understanding of the metabolism of quinolizidine‐type alkaloids in S. alopecuroides. Methods: Hydrophilic interaction chromatography coupled with triple‐quadrupole tandem mass spectrometry (HILIC‐TQ‐MS/MS) in multiple‐reaction monitoring (MRM) mode were used to determine seven quinolizidine‐type alkaloids and their biosynthetic precursor, lysine, in S. alopecuroides. Results: A good separation was obtained on an ultra high‐performance liquid chromatography (UHPLC) amide column within 7 min. The overall limits of detection (LODs) were between 1.13 and 2.81 ng/ml, and limits of quantitation (LOQs) were between 3.80 and 8.48 ng/ml. The developed method was successfully applied to 21 samples of S. alopecuroides. The seeds had the highest concentration of alkaloids among the different plant parts. Oxymatrine and oxysophocarpine were the two most abundant alkaloids in all of the different parts and at different phenological growth stages. The contents of quinolizidine alkaloids showed correlations with lysine. Conclusion: A rapid and sensitive analytical method was established for the simultaneous determination of seven quinolizidine‐type alkaloids and their biosynthetic precursor, lysine, in S. alopecuroides; the content of lysine may be used as a marker to predict alkaloid production. [ABSTRACT FROM AUTHOR]

Mechanosensitivity in biology, e.g., cells responding to material stiffness, is important for the design of synthetic biomaterials. It is caused by protein receptors able to undergo conformational changes depending on mechanical stress during adhesion processes. Here the elastic modulus dependence of adhesive interactions is systematically quantified using ligand-receptor model systems that are generally not thought to be mechanosensitive: biotin-avidin, mannose-concanavalin A, and electrostatic interactions between carboxylic acids and polycationic surfaces. Interactions are measured by microgel sensors of different stiffness adhering to surfaces presenting a corresponding binding partner. Adhesion is generally decreased for softer microgels due to reduced density of binding partners. Density-normalized data show that low-affinity carbohydrate ligands exhibit reduced binding in softer networks, probably due to increased network conformational entropy. However, in case of stronger interactions with large interaction range (electrostatic) and large lifetime (biotin-avidin) density normalized adhesion is increased. This suggests compensation of entropic repulsion for softer networks probably due to their increased mechanical deformation upon microgel adhesion and enhanced cooperative binding. In essence, experiments indicate that soft interacting polymer materials exhibit entropic repulsion, which can be overcome by strongly interacting species in the network harnessing network flexibility in order to increase adhesion. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether umbelliferone (Umb) could attenuate insulin resistance in unpredictable chronic mild stress (CUMS)-induced rats. Behavioral changes were evaluated through sucrose preference test (SPT), open-field test, forced swimming test, and tail suspension test (TST), suggesting that Umb (20 and 40 mg/kg) could effectively improve depression symptoms. Oral glucose tolerance test and serum insulin indicated that Umb attributed to the control of blood glucose levels. The phosphorylation of insulin receptor, insulin receptor substrate (IRS)−1, glycogen synthase kinase-3β, PI3K, and Akt was increased in Umb (20 and 40 mg/kg) treatment according to Western blot analysis. Taken together, the current results suggested the ameliorative effect of Umb against insulin resistance in the CUMS-induced rats. © 2016 IUBMB Life, 68(5):403-409, 2016 [ABSTRACT FROM AUTHOR]

Amino acids are naturally occurring compounds in many edible or medicinal plants, which possess a variety of pharmacological effects on humans. The aim of this study is to develop and validate a hydrophilic interaction LC coupled with MS/ MS method for the absolute and relative quantification of amino acids without derivatization. The application of this method has been proven through 20 naturally occurring amino acids in 21 samples from different parts and phenological growth stage of Sophora alopecuroides. The method was performed on an ultra-high performance LC separation system coupled with ESI-MS on a triple quadrupole mass spectrometer. The proposed absolute quantitative method was fully validated in terms of linearity, sensitivity, precision, repeatability as well as recovery. The analysis results showed that S. alopecuroides is rich in free amino acids. In addition, relative quantitative determination of amino acids with several amino acids selected for the best accuracy was investigated. The accuracies of relative quantitative method for amino acids determinations suggest that it is feasible to quantify amino acids by the proposed relative quantitative determination method, which contributes to breaking through the choke point of lack of standards. [ABSTRACT FROM AUTHOR]