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Quality consistency of Glycyrrhiza formula granules is essential for guaranteeing clinical efficacy. However, a suitable method to accurately and conveniently evaluate the consistency of the clinical efficacy of Glycyrrhiza formula granules is currently not available. This study established a method for the simultaneous determination of 12 active components in Glycyrrhiza formula granules using ultra‐high‐performance liquid chromatography coupled with quadrupole‐time‐of‐flight tandem mass spectrometry. The rate of inhibition of cyclooxygenase‐2 by different batches of Glycyrrhiza formula granules was determined. Near‐infrared spectra were collected for different batches of Glycyrrhiza formula granules to detect their biological activity in the inhibition of cyclooxygenase‐2. The quality consistency of the 11 batches of Glycyrrhiza formula granules was evaluated using principal component and correlation analyses. The results showed significant differences in the formula granules of Glycyrrhiza uralensis produced by the different manufacturers. Some differences were also observed among batches of formula granules produced by the same manufacturer. Correlation analysis of the chemical components and cyclooxygenase‐2 activity showed that glycyrrhizic acid, liquiritin, and isoliquiritin were the main active components of Glycyrrhiza. Correlation analysis of the near‐infrared spectra and cyclooxygenase‐2 inhibition activity showed a high correlation between the active components and three characteristic bands: 3383–3995, 4227–4651, and 5315–5878 cm−1. In this study, the main active anti‐inflammatory components of Glycyrrhiza granules were screened. Thus, the near‐infrared spectrum and characteristic active band of multi‐index active components can be used to quickly detect the quality consistency of Glycyrrhiza formula granules, thereby improving the ability to control the quality and consistency of these granules. [ABSTRACT FROM AUTHOR]

• Porcine KCNQ1OT1 is a paternally expressed lncRNA. • Porcine KCNQ1OT1 has RNA splicing and a shorter 5′ end compared to human. • KCNQ1OT1 can bind to the promoter of regulatory genes. • Porcine KCNQ1OT1 regulates CDKN1C expression through chromosome folding. Long noncoding RNAs (lncRNAs) are implicated in a number of regulatory functions in eukaryotic genomes. In humans, KCNQ1OT1 is a 91 kb imprinted lncRNA that inhibits multiple surrounding genes in cis. Among them, CDKN1C is closely related to KCNQ1OT1 and is involved in multiple epigenetic disorders. Here, we found that pigs also had a relatively conserved paternal allele expressing KCNQ1OT1 and had a shorter 5′ end (∼27 kb) compared to human KCNQ1OT1. Knockdown of KCNQ1OT1 using antisense oligonucleotides (ASO) showed that upregulation of CDKN1C expression in pigs. However, porcine KCNQ1OT1 did not affect the DNA methylation status of the CpG islands in the promoters of KCNQ1OT1 and CDKN1C. Inhibition of DNA methyltransferase using Decitabine treatment resulted in a significant increase in both KCNQ1OT1 and CDKN1C expression, suggesting that the regulation between KCNQ1OT1 and CDKN1C may not be dependent on RNA interference. Further use of chromosome conformation capture and reverse transcription-associated trap detection in the region where CDKN1C was located revealed that KCNQ1OT1 bound to the CDKN1C promoter and affected chromosome folding. Phenotypically, inhibition of KCNQ1OT1 at the cumulus-oocyte complex promoted cumulus cell transformation, and to upregulated the expression of ALPL at the early stage of osteogenic differentiation of porcine bone marrow mesenchymal stem cells. Our results confirm that the expression of KCNQ1OT1 imprinting in pigs as well as porcine KCNQ1OT1 regulates the expression of CDKN1C through direct promoter binding and chromatin folding alteration. And this regulatory mechanism played an important role in cell differentiation. [ABSTRACT FROM AUTHOR]

Drug-induced liver injury (DILI) is a common adverse drug reaction (ADR) and a serious threat to health that affects disease treatments. At present, no targeted clinical drugs are available for DILI. Traditional natural medicines have been widely used as health products. Some natural medicines exert specific hepatoprotective effects, with few side effects and significant clinical efficacy. Thus, natural medicines may be a promising direction for DILI treatment. In this review, we summarize the current knowledge, common drugs and mechanisms of DILI, as well as the clinical trials of natural drugs and their bioactive components in anticipation of the future development of potential hepatoprotective drugs. [ABSTRACT FROM AUTHOR]

Aflatoxins are widely occurring food contaminants that are particularly harmful to dairy products and cows. The plant polyphenol resveratrol has been reported to have a good effect on increasing the resistance of cells toward toxins. Therefore, we measured the effects of aflatoxin B1 and resveratrol on the viability of the MAC-T cow mammary epithelial cell line. The appropriate treatment concentrations were assayed (12.81 μM aflatoxin B1 and 43.81 μM resveratrol) to verify the protective effect of resveratrol toward mammary epithelial cells. The results showed that resveratrol alleviates aflatoxin B1-induced cytotoxicity, including the increase in ROS and the decrease in mitochondrial membrane potential (MMP) and apoptosis in MAC-T cells. The expression of mRNA transcripts (including Nrf2, Keap1, NQO1, HO-1, SOD2 and HSP70) for components of the Nrf2 signaling pathway was evaluated by real-time fluorescent quantitative PCR, with resveratrol also exhibiting a good regulatory effect. Thus, resveratrol was shown to have an ameliorating effect on aflatoxin toxicity in MAC-T cells. • Resveratrol can recovery the MAC-T cell viability decline induced by AFB1. • Resveratrol inhibits AFB1-induced apoptosis in the MAC-T cell. • Resveratrol may play positive roles via Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

The quality of traditional Chinese medicine (TCM) guarantees its clinical efficacy. Although advanced analytical techniques and methods can accurately determine the content of chemical components in TCM, it is difficult to accurately determine its clinical efficacy. In addition, the current analytical methods and technologies are complex and have difficulty meeting the requirements of a rapid, accurate and convenient determination of TCM quality. In this study, we first propose the concept of "indistinct" evaluation of the quality of TCM, that is, combining biological potency with character evaluation, quantifying the character evaluation, and preparing the safflower quality grade evaluation card based on the character analysis, which provides research ideas and methods for the rapid and accurate evaluation of the quality of TCM. We determined the biological potency of different batches of safflower based on the in vitro antiplatelet aggregation model and divided the safflower samples into two grades based on the biological potency. We further collected the color information of different grades of safflower samples, quantified the color information of different grades of safflower, drew a quality grade evaluation card for the rapid judgment of safflower quality grade and verified its accuracy by pharmacodynamic evaluation. To further analyze the differences in the material basis of different grades of safflower, the LC-MS method was used to simultaneously determine the contents of 19 chemical components, such as myricetin, in different grades of safflower samples to analyze the differences in the material basis of different grades of safflower. The result shows that the different grades of safflower exhibited significant differences in color. The pharmacodynamic results show that the quality evaluation card prepared based on color information can accurately evaluate quality, and the effect of first-class safflower is significantly better than that of second-class safflower. The chemical analysis results of different grades of safflower show that there are also significant differences between them, among which hypericin, 6-hydroxyapin-6-O-glucose-7-O-glucuronide, 6-hydroxykaempferol-3,6-O-diglucoside-7-O-glucuronic acid glycoside, 6-hydroxykaempferol-3,6,7-tri-O-glucoside and hydroxysafflower yellow A exhibit significant differences, which may be the main differentiating components of different grades of safflower. This study preliminarily confirmed that the "indistinct" evaluation of the quality of TCM based on character analysis is accurate and scientific, and the quality evaluation card prepared can accurately judge the quality of TCM, providing a reference for the rapid application of TCM character evaluation. • Indistinct evaluation of the quality of TCM is accurate and scientific. • The color of safflower truly exhibits a significant correlation with its efficacy. • The QEC can accurately judge the quality of TCM rapid and accurate. [ABSTRACT FROM AUTHOR]

• Shear capacities of AL- and steel-timber joints by 1-row screws are the same. • Capacity of AL-timber joints by 3-row screws is not reduced when two plastic hinges. • The discrimination coefficient is introduced to predict failure modes of the screws. Aluminum alloy has significant advantages in reducing self-weight and improving the corrosion resistance compared with steel. The performance of the interface between timber and H-shaped aluminum alloy beams is the key to designing aluminum-timber composite beams. Twelve groups of double-shear tests were conducted in this paper to investigate the influences of glulam strength, the type and size of connectors, and the row number of connectors on shear capacity, and the failure modes of connections were evaluated. The results have shown that, compared with the specimens connected by screws, the bolt heads of the specimens connected by bolts tended to cause local crushing failure of the glulam. There is negligible difference between the shear capacities of aluminum-timber and steel-timber connection when connected by single-row screws. For the group effect of the screws, the reduction of shear capacity of aluminum-timber connections is slightly higher than that of steel-timber connections when connected by multi-row screws. The shear capacity of aluminum-timber connections with multi-row screws needs to be reduced when one plastic hinge appears in the screws (failure mode II). It does not need to be reduced when two plastic hinges appear in the screws (failure mode III), and the theoretical value has a large safety margin. The length-to-diameter ratio λ is the main factor affecting the failure modes of the screws, and the coefficient λ y is introduced to discriminate the failure modes. [ABSTRACT FROM AUTHOR]

Vesicles, including lipid vesicles, surfactant vesicles, as well as polymer vesicles, have been extensively investigated over the past fifty years. Among them, polymer vesicles have attracted more and more attention because of their low permeability, superior stability and toughness, in addition to the numerous possibilities for tailoring physical, chemical and biological properties. Polymer vesicles are generally fabricated through the self-assembly of amphiphilic polymers with a linear architecture. Recently, as representative polymers with a highly branched three-dimensional architecture, hyperbranched polymers have also exhibited great potential for preparing vesicles. The resultant hyperbranched polymer vesicles, defined as branched-polymersomes (BPs), have shown unique properties, such as giant and easily tuned vesicle sizes, facile functionalization, a special formation mechanism, and appealing solution behaviours. In this tutorial review, ten years of advances in BPs have been summarized since their first discovery in the year 2004, including the syntheses of vesicle-forming hyperbranched polymers, self-assembly methods, self-assembly mechanisms, as well as the special properties. In addition, the cytomimetic, biomedical and other initiatory applications of BPs are also included. [ABSTRACT FROM AUTHOR]

Supramolecular dendritic polymers (SDPs), which perfectly combinethe advantages of dendritic polymers with those of supramolecularpolymers, are a novel class of non-covalently bonded, highly branchedmacromolecules with three-dimensional globular topology. Because oftheir dynamic/reversible nature, unique topological structure, andexceptional physical/chemical properties (e.g., low viscosity, highsolubility, and a large number of functional terminal groups), SDPshave attracted increasing attention in recent years in both academicand industrial fields. In particular, the reversibility of non-covalentinteractions endows SDPs with the ability to undergo dynamic switchingof structure, morphology, and function in response to various externalstimuli, such as pH, temperature, light, stress, and redox agents,which further provides a flexible and robust platform for designingand developing smart supramolecular polymeric materials and functionalsupramolecular devices. [ABSTRACT FROM AUTHOR]

Climate is one of the most important drivers for adaptive evolution in forest trees. Climatic selection contributes greatly to local adaptation and intraspecific differentiation, but this kind of selection could also have promoted interspecific divergence through ecological speciation. To test this hypothesis, we examined intra- and interspecific genetic variation at 25 climate-related candidate genes and 12 reference loci in two closely related pine species, Pinus massoniana Lamb. and Pinus hwangshanensis Hisa, using population genetic and landscape genetic approaches. These two species occur in Southeast China but have contrasting ecological preferences in terms of several environmental variables, notably altitude, although hybrids form where their distributions overlap. One or more robust tests detected signals of recent and/or ancient selection at two-thirds (17) of the 25 candidate genes, at varying evolutionary timescales, but only three of the 12 reference loci. The signals of recent selection were species specific, but signals of ancient selection were mostly shared by the two species likely because of the shared evolutionary history. FST outlier analysis identified six SNPs in five climate-related candidate genes under divergent selection between the two species. In addition, a total of 24 candidate SNPs representing nine candidate genes showed significant correlation with altitudinal divergence in the two species based on the covariance matrix of population history derived from reference SNPs. Genetic differentiation between these two species was higher at the candidate genes than at the reference loci. Moreover, analysis using the isolation-with-migration model indicated that gene flow between the species has been more restricted for climate-related candidate genes than the reference loci, in both directions. Taken together, our results suggest that species-specific and divergent climatic selection at the candidate genes might have counteracted interspecific gene flow and played a key role in the ecological divergence of these two closely related pine species. [ABSTRACT FROM AUTHOR]

Hyperbranched polymers (HBPs), invented at the end of 1980s, are one important subclass of the fourth generation macromolecular architectures following the linear, branched, and crosslinking polymers. Due to their unique topological structure and interesting physical/chemical properties, HBPs have attracted wide attention from both academia and industry. HBPs are composed of linear units, dendritic units, and terminal units. The degree of branching (DB), a term to describe the composition of these three structure units and thus the branching architecture of polymers, is one of the most important intrinsic parameters for HBPs. This review has summarized the effect of the DB on the physical and chemical properties of HBPs, including the rheological property, crystallization and melting behaviors, glass transition, thermal and hydrolytic degradations, phase characteristics, lower critical solution temperature phase transition, optoelectronic properties, encapsulation capability, self-assembly behavior, biomedical applications, and so on. Such a structure and property relationship will build a bridge between the syntheses and applications of HBPs, especially in the application areas of functional materials, biomedical materials, and nanotechnology. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1277-1286, 2011 [ABSTRACT FROM AUTHOR]

Abstract: Water-soluble titanate nanotubes (TNTs) with temperature-responsive shells were synthesized by grafting poly(N-isopropylacrylamide) (PNIPAAm) from TNTs via surface atom transfer radical polymerization (ATRP) using ATRP agent functionalized TNTs as macroinitiator. Proton Nuclear magnetic resonance spectroscopy (1H NMR), Fourier-transform infrared (FT-IR) and thermogravimetric analyses (TGA) results prove the successful graft of PNIPAAm chains from TNTs. TGA shows that the amount of PNIPAAm grown from the TNTs increased with the increase of monomer/initiator ratio. Transmission electron microscope (TEM) measurements displays the obtained TNTs-g-PNIPAAm nanohybrids have a core–shell structure of TNT cores and PNIPAAm shells. In addition, the functional nanotubes demonstrate a reversible low critical solution temperature (LCST) transition with the increase of solution temperature. The synthetic method presented here can also be extended to graft other stimuli responsive polymers from TNTs. [Copyright &y& Elsevier]

Abstract: In recent years, polymer microcapsules have attracted more and more attention because of their specific properties and applications in encapsulation and drug delivery. Great effort has been made to investigate the preparation methods, structure controls as well as the property designs for the polymer microcapsules. In this work, we reported an effective route for the preparation of poly(β-hydroxybutyrate) (PHB) and poly(lactic acid) (PLA) hollow spheres with controlled wall thickness, which involves the graft polymerization of the biodegradable polymers from the surface of silica spheres followed by removing the template cores. Nuclear magnetic resonance spectroscopy (NMR), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscope (TEM) have been used to prove the structure of the hollow sphere and the intermediates. The result reveals that with the increase of reaction time the wall thickness of the hollow sphere will increase gradually. [Copyright &y& Elsevier]

Artificial vesicles are recognized as powerful platforms for a large body of research across the disciplines of chemistry, physics and biology. Despite the great progress, control of the size distribution to make uniform vesicles remains fundamentally difficult due to the highly uncontrollable growth kinetics, especially for micron‐sized vesicles. Here we report a template‐free living self‐assembly method to prepare monodisperse vesicles around 1 μm from an alternating copolymer. The polymer forms nanodisks (ca. 9 nm) in N,N‐dimethylformamide (DMF), acting as seeds for subsequent growth. By adding water, the nanodisks gradually grow into larger circular bilayer nanosheets, which bend to crowns and continue to grow into uniform micron‐sized vesicles. The first‐order growth kinetics as well as the small size polydispersity index (<0.1) suggests the living self‐assembly characteristics. This work paves a new way in both living self‐assembly and monodisperse polymer vesicles. [ABSTRACT FROM AUTHOR]

Artificial vesicles are recognized as powerful platforms for a large body of research across the disciplines of chemistry, physics and biology. Despite the great progress, control of the size distribution to make uniform vesicles remains fundamentally difficult due to the highly uncontrollable growth kinetics, especially for micron‐sized vesicles. Here we report a template‐free living self‐assembly method to prepare monodisperse vesicles around 1 μm from an alternating copolymer. The polymer forms nanodisks (ca. 9 nm) in N,N‐dimethylformamide (DMF), acting as seeds for subsequent growth. By adding water, the nanodisks gradually grow into larger circular bilayer nanosheets, which bend to crowns and continue to grow into uniform micron‐sized vesicles. The first‐order growth kinetics as well as the small size polydispersity index (<0.1) suggests the living self‐assembly characteristics. This work paves a new way in both living self‐assembly and monodisperse polymer vesicles. [ABSTRACT FROM AUTHOR]

Decreasing gas penetration has noticeable effects on the durability and performance of Nafion based proton exchange membranes (PEMs). Experimental studies showed that adding imidazolyl groups into Nafion could reduce the hydrogen permeation in the membrane, while causing the substantial increase in power density. Nonetheless, the microscopic mechanism of doping on the reduction of hydrogen permeation is remain unclear. In this work, molecular dynamics simulation was performed to understand the transport behaviors of hydrogen in polyvinylimidazole (PVMZ)/Nafion composite membranes at the molecular level. The simulation results indicate that there are different degrees of effects about the polymer phase and aqueous domain on the diffusion kinetics of hydrogen in Nafion and PVMZ/Nafion at low and high hydration levels. With the increase of water content, the hydrogen molecules will migrate from the polymer phase to the polymer/water interface in Nafion and PVMZ/Nafion membranes. At low water content, the more free volume and the more pores in Nafion membrane are conducive to the diffusion of hydrogen than that in PVMZ/Nafion membrane to a greater extent. For the aqueous domain, the smaller and the rougher surface of water clusters in PVMZ/Nafion membranes have a certain limiting effect on the diffusion of hydrogen molecules than that in Nafion membranes at high water content. Consequently, at low water contents (λ ≤ 9), the self-diffusion coefficient of hydrogen (D H2) increases slowly from 0.55 to 1.01 (× 10−5 cm2/s) in Nafion membrane and from 0.26 to 0.53 (× 10−5 cm2/s) in PVMZ/Nafion membrane. In contrast, at high water contents (λ ≥ 9), the D H2 increases rapidly from 1.01 to 2.35 (× 10−5 cm2/s) in Nafion membranes and from 0.53 to 1.74 (× 10−5 cm2/s) in PVMZ/Nafion membranes. The current work can provide a fundamental understanding for experimentally designing new type Nafion based PEMs for hydrogen fuel cells. [Display omitted] • A similar but lower diffusion of hydrogen occurs in PVMZ/Nafion than Nafion under different water contents. • There are different effects for polymer phase and aqueous domain on the diffusion kinetics of hydrogen in Nafion and PVMZ/Nafion. • The hydrogen in Nafion and PVMZ/Nafion tends to migrate toward the polymer/water interface as increasing water content. [ABSTRACT FROM AUTHOR]

Plant domestication are evolutionary experiments conducted by early farmers since thousands years ago, during which the crop wild progenitors are artificially selected for desired agronomic traits along with dramatic genomic variation in the course of moderate to severe bottlenecks. However, previous investigations are mainly focused on small-effect variants, while changes in gene contents are rarely investigated due to the lack of population-level assemblies for both the crop and its wild relatives. Here, we applied comparative genomic analyses to discover gene gain and loss during grapevine domestication using long-read assemblies of representative population samples for both domesticated grapevines (V. vinifera ssp. vinifera) and their wild progenitors (V. vinifera ssp. sylvestris). Only ∼7% of gene families were shared by 16 Vitis genomes while ∼8% of gene families were specific to each accession, suggesting dramatic variations of gene contents in grapevine genomes. Compared to wild progenitors, the domesticated accessions exhibited an increased presence of genes associated with asexual reproduction, while the wild progenitors showcased a higher abundance of genes related to pollination, revealing the transition from sexual reproduction to clonal propagation during domestication processes. Moreover, the domesticated accessions harbored fewer disease-resistance genes than wild progenitors. The SVs occurred frequently in aroma and disease-resistance related genes between domesticated grapevines and wild progenitors, indicating the rapid diversification of these genes during domestication. Our study provides insights and resources for biological studies and breeding programs in grapevine. Comparative genomic analyses of wild and cultivated grapevine at the population level reveal dramatic variations in gene content during grapevine domestication. [ABSTRACT FROM AUTHOR]

Epigenetic modifications play critical roles during somatic cell nuclear transfer (SCNT) embryo development. Whether RNA N6‐methyladenosine (m6A) affects the developmental competency of SCNT embryos remains unclear. Here, we showed that porcine bone marrow mesenchymal stem cells (pBMSCs) presented higher RNA m6A levels than those of porcine embryonic fibroblasts (pEFs). SCNT embryos derived from pBMSCs had higher RNA m6A levels, cleavage, and blastocyst rates than those from pEFs. Compared with pEFs, the promoter region of METTL14 presented a hypomethylation status in pBMSCs. Mechanistically, DNA methylation regulated METTL14 expression by affecting the accessibility of transcription factor SP1 binding, highlighting the role of the DNA methylation/SP1/METTL14 pathway in donor cells. Inhibiting the DNA methylation level in donor cells increased the RNA m6A level and improved the development efficiency of SCNT embryos. Overexpression of METTL14 significantly increased the RNA m6A level in donor cells and the development efficiency of SCNT embryos, whereas knockdown of METTL14 suggested the opposite result. Moreover, we revealed that RNA m6A‐regulated TOP2B mRNA stability, translation level, and DNA damage during SCNT embryo development. Collectively, our results highlight the crosstalk between RNA m6A and DNA methylation, and the crucial role of RNA m6A during nuclear reprogramming in SCNT embryo development. [ABSTRACT FROM AUTHOR]

A stable substrate is extraordinarily important for the trace detection of Surface Enhanced Raman Scattering technique. We have designed in this paper a simple seed growth method to prepare Ag@ZrO 2 core-shell nanoparticles as well as regulate the core-shell ratio by adjusted concentration of zirconium propoxides added. The shell thickness effect and spacing on SERS activities have been simulated in different finite time domains, which goes perfectly with those previous experiment results. With Ag@ZrO 2 core-shell nanoparticles adopted as the SERS substrate and R6G as molecular probe, the detection range could reach as great as 10-8 M. The regression model, obtained through principal component analysis, is adopted for some rapid and precise detection; and the determination coefficient (R2) is going up to 0.9743, proving that the SERS substrate we have prepared has extremely high detection accuracy. To explore the stability of core-shell nanoparticles, we have taken both two different cases of strong acid solution as well as strong alkali solution for the core-shell nanoparticle etching, and this is how a SERS test could be carried out. These experimental results have indicated that the outer zirconia layer could keep the silver surface from oxidation and its stability is ensured, quite crucial for the applied SERS. Image 1 • Simple seed growth method to prepare Ag@ZrO 2 core-shell nanoparticles is proposed. • The reliability of the Ag@ZrO 2 core-shell nanoparticles immersed in strong acid and strong alkali solution. • Ag@ZrO 2 adopted as the SERS substrate, the LOD of R6G could reach as great as 10-8 M. [ABSTRACT FROM AUTHOR]

The macroscopic molecular self-assembly of an amphiphilic hyperbranched copolymer in acetone generated multiwalled tubes millimeters in diameter and centimeters in length. The thickness of the tube walls approaches 400 nanometers, and the walls have an inhomogeneous lamella structure that alternates between ordered hydrophilic domains and amorphous, partly irregular hydrophilic domains. [ABSTRACT FROM AUTHOR]

Hybrid organic–inorganic perovskite single crystals, compared with their polycrystalline counterparts in thin films, are free from grain boundaries and have fewer defects, and therefore are promising in high‐performance optoelectronic devices. Recently, the crystal‐structure anisotropy in perovskites has been utilized to achieve polarization‐sensitive photodetectors. Here, it is shown that under 532 nm linearly polarized illumination, although MAPbBr3 (MA=CH3NH3+1) single crystals possess weak in‐plane anisotropy, nanogratings made on the crystal surface lead to high polarization photodetection sensitivity of ≈2.2 comparable with that of the isotropic perovskite crystals and nanowires, while enhancing both the photodetection responsivity and external quantum efficiency. The surface nanopattern induced polarization sensitivity may find interesting applications in future optoelectronic devices. [ABSTRACT FROM AUTHOR]

The selective semihydrogenation of C2H2 to C2H4 in crude C2H4 (with ~1 vol % C2H2 contamination) is a crucial process in the manufacture of polyethylene. Comparing to conventional thermalcatalytic route with Pd as catalyst under high temperature with H2 as hydrogen source, photocatalytic C2H2 reduction reaction with H2O as hydrogen source can achieve high selectivity under milder conditions, but has rarely been reported. Here, we present a kind of ultrathin metal–organic framework nanosheets (Cu‐Co‐MNSs) that demonstrate excellent catalytic activities in the semihydrogenation of C2H2. Employing Ru(bpy)32+ as the photosensitizer, this catalyst attains a noteworthy turnover number (TON) of 2124 for C2H4, coupled with an impressive selectivity of 99.5 % after 12 h visible light irradiation. This performance is comparable to molecular catalysts and notably surpasses the efficiency of bulk metal–organic framework materials. Furthermore, Cu‐Co‐MNSs achieve a 99.95 % conversion of C2H2 under industrial relevant conditions (1.10 % C2H2 in C2H4) with 90.3 % selectivity for C2H4 over C2H6, demonstrating a great potential for polymer‐grade C2H4 production. [ABSTRACT FROM AUTHOR]

A Zinc phthalocyanine-based (ZnPc–PA) polymeric micelle around 70 nm and with dual-modal PTT/PDT functions for non-antibiotic bacteria eradication was developed. It showed an excellent bacterial killing efficiency of 95.2% and 96.7% in vitro against Methicillin-resistant Staphylococcus aureus (MRSA) and its biofilm, respectively. Furthermore, the in vivo experiments proved its great potential for implant-associated infection (IAI). [ABSTRACT FROM AUTHOR]

Hierarchical self‐assembly of synthetic polymers in solution represents one of the sophisticated strategies to replicate the natural superstructures which lay the basis for their superb functions. However, it is still quite challenging to increase the degree of complexity of the as‐prepared assemblies, especially in a large scale. Liquid–liquid phase separation (LLPS) widely exists in cells and is assumed to be responsible for the formation of many cellular organelles without membranes. Herein, through integrating LLPS with the polymerization‐induced self‐assembly (PISA), a coacervate‐assisted PISA (CAPISA) methodology to realize the one‐pot and scalable preparation of hierarchical bishell capsules (BCs) from nanosheets with ultrathin lamellae phase (sub‐5 nm), microflakes, unishell capsules to final BCs in a bottom‐up sequence is presented. Both the self‐assembled structure and the dynamic formation process of BCs have been disclosed. Since CAPISA has combined the advantages of coacervates, click chemistry, interfacial reaction and PISA, it is believed that it will become a promising option to fabricate biomimetic polymer materials with higher structural complexity and more sophisticated functions. [ABSTRACT FROM AUTHOR]

Liver fibrosis refers to a complex inflammatory response caused by multiple factors, which is a known cause of liver cirrhosis and even liver cancer. As a valuable medicine food homology herb, saffron has been widely used in the world. Saffron is commonly used in liver-related diseases and has rich therapeutic and health benefits. The therapeutic effect is satisfactory, but its mechanism is still unclear. In order to clarify these problems, we planned to determine the pharmacological effects and mechanisms of saffron extract in preventing and treating liver fibrosis through network pharmacology analysis combined with in vivo validation experiments. Through UPLC-Q-Exactive-MS analysis, a total of fifty-six nutrients and active ingredients were identified, and nine of them were screened to predict their therapeutic targets for liver fibrosis. Then, network pharmacology analysis was applied to identify 321 targets for saffron extract to alleviate liver fibrosis. Functional and pathway enrichment analysis showed that the putative targets of saffron for the treatment of hepatic fibrosis are mainly involved in the calcium signaling pathway, the HIF-1 signaling pathway, endocrine resistance, the PI3K/Akt signaling pathway, lipid and atherosclerosis, and the cAMP signaling pathway. Based on the CCl4-induced liver fibrosis mice model, we experimentally confirmed that saffron extract can alleviate the severity and pathological changes during the progression of liver fibrosis. RT-PCR and Western blotting analysis confirmed that saffron treatment can prevent the CCl4-induced upregulation of HIF-1α, VEGFA, AKT, and PI3K, suggesting that saffron may regulate AKT/HIF-1α/VEGF and alleviate liver fibrosis. [ABSTRACT FROM AUTHOR]

This article explores the origin and evolution of the Y chromosome in kiwifruit. The sex determination of kiwifruit is genetically controlled by an XY system, and two Y-linked sex-determining genes, Shy Girl (SyGl) and Friendly Boy (FrBy), have been identified. The study examines the structural reorganization of the kiwifruit Y chromosome and identifies the sex-determining region (SDR) on chromosome 25 in A. chinensis and chromosome 12 in A. eriantha. The research also investigates the genomic diversity and evolutionary trajectories of the Y chromosome in kiwifruit. [Extracted from the article]

Background: Several studies have mined short-read RNA sequencing datasets to identify long non-coding RNAs (lncRNAs), and others have focused on the function of individual lncRNAs in abiotic stress response. However, our understanding of the complement, function and origin of lncRNAs – and especially transposon derived lncRNAs (TE-lncRNAs) - in response to abiotic stress is still in its infancy. Results: We utilized a dataset of 127 RNA sequencing samples that included total RNA datasets and PacBio fl-cDNA data to discover lncRNAs in maize. Overall, we identified 23,309 candidate lncRNAs from polyA+ and total RNA samples, with a strong discovery bias within total RNA. The majority (65%) of the 23,309 lncRNAs had sequence similarity to transposable elements (TEs). Most had similarity to long-terminal-repeat retrotransposons from the Copia and Gypsy superfamilies, reflecting a high proportion of these elements in the genome. However, DNA transposons were enriched for lncRNAs relative to their genomic representation by ~ 2-fold. By assessing the fraction of lncRNAs that respond to abiotic stresses like heat, cold, salt and drought, we identified 1077 differentially expressed lncRNA transcripts, including 509 TE-lncRNAs. In general, the expression of these lncRNAs was significantly correlated with their nearest gene. By inferring co-expression networks across our large dataset, we found that 39 lncRNAs are as major hubs in co-expression networks that respond to abiotic stress, and 18 appear to be derived from TEs. Conclusions: Our results show that lncRNAs are enriched in total RNA samples, that most (65%) are derived from TEs, that at least 1077 are differentially expressed during abiotic stress, and that 39 are hubs in co-expression networks, including a small number that are evolutionary conserved. These results suggest that lncRNAs, including TE-lncRNAs, may play key regulatory roles in moderating abiotic responses. [ABSTRACT FROM AUTHOR]

Pulmonary fibrosis is a chronic progressive interstitial lung disease caused by a variety of etiologies. The disease can eventually lead to irreversible damage to the lung tissue structure, severely affecting respiratory function and posing a serious threat to human health. Currently, glucocorticoids and immunosuppressants are the main drugs used in the clinical treatment of pulmonary fibrosis, but their efficacy is limited and they can cause serious adverse effects. Traditional Chinese medicines have important research value and potential for clinical application in anti-pulmonary fibrosis. In recent years, more and more scientific researches have been conducted on the use of traditional Chinese medicine to improve or reduce pulmonary fibrosis, and some important breakthroughs have been made. This review paper systematically summarized the research progress of pharmacological mechanism of traditional Chinese medicines and their active compounds in improving or reducing pulmonary fibrosis. We conducted a systematic search in several main scientific databases, including PubMed, Web of Science, and Google Scholar, using keywords such as idiopathic pulmonary fibrosis, pulmonary fibrosis, interstitial pneumonia, natural products, herbal medicine, and therapeutic methods. Ultimately, 252 articles were included and systematically evaluated in this analysis. The anti-fibrotic mechanisms of these traditional Chinese medicine studies can be roughly categorized into 5 main aspects, including inhibition of epithelial-mesenchymal transition, anti-inflammatory and antioxidant effects, improvement of extracellular matrix deposition, mediation of apoptosis and autophagy, and inhibition of endoplasmic reticulum stress. The purpose of this article is to provide pharmaceutical researchers with information on the progress of scientific research on improving or reducing Pulmonary fibrosis with traditional Chinese medicine, and to provide reference for further pharmacological research. [ABSTRACT FROM AUTHOR]

Tetra-amido macrocyclic ligand (TAML) activator is a functional analog of peroxidase enzymes, which activates hydrogen peroxide (H 2 O 2 ) to form high valence iron-oxo complexes that selectively degrade persistent aromatic organic contaminants (ACs) in water. Here, we develop quantitative structure–activity relationship (QSAR) models based on measured pseudo first-order kinetic rate coefficients ( k obs ) of 29 ACs (e.g., phenols and pharmaceuticals) oxidized by TAML/H 2 O 2 at neutral and basic pH values to gain mechanistic insight on the selectivity and pH dependence of TAML/H 2 O 2 systems. These QSAR models infer that electron donating ability ( E HOMO ) is the most important AC characteristic for TAML/H 2 O 2 oxidation, pointing to a rate-limiting single-electron transfer (SET) mechanism. Oxidation rates at pH 7 also depend on AC reactive indices such as f m i n − and qH + , which respectively represent propensity for electrophilic attack and the most positive net atomic charge on hydrogen atoms. At pH 10, TAML/H 2 O 2 is more reactive towards ACs with a lower hydrogen to carbon atoms ratio (#H:C), suggesting the significance of hydrogen atom abstraction. In addition, ln k obs of 14 monosubstituted phenols is negatively correlated with Hammett constants ( σ ) and exhibits similar sensitivity to substituent effects as horseradish peroxidase. Although accurately predicting degradation rates of specific ACs in complex wastewater matrices could be difficult, these QSAR models are statistically robust and help predict both relative degradability and reaction mechanism for TAML/H 2 O 2 -based treatment processes. [ABSTRACT FROM AUTHOR]

Construction of polymer‐based artificial solid‐electrolyte interphase films on Zn metal anode holds great potential in the suppression of both dendrite growth and side reaction in rechargeable aqueous Zn‐ion batteries. However, the traditional polymer films suffer from the critical issues of sluggish Zn2+ transport kinetics and rigid interface. Herein, zinc alginate (ZA) hydrogel is designed and prepared as a dynamic interface and Zn2+ redistributor on Zn anode via in situ cross‐linking reaction. The zincophilic and negatively charged carboxyl groups of ZA promote the transport of Zn2+ ions along a "Z‐type" pathway, the repulsion of free SO42‐ anions, and the desolvation of Zn2+ ions, consequently leading to the homogeneous deposition of Zn and the effective suppression of side reaction. Additionally, the dynamic flexibility of ZA hydrogel endows the Zn anode with self‐adapting interface to accommodate the volume variation and repair the possible ruptures, thereby guaranteeing the long‐term cycling stability. Assisted by the ZA layer, the Zn anode achieves a prolonged lifespan over 2200 h without the formation of Zn dendrites and by‐products. Outstanding cycling stability is also demonstrated for the Zn anode when coupled with MnO2 cathode, further demonstrating its prospects for practical application. [ABSTRACT FROM AUTHOR]

Inspired by carbon monoxide dehydrogenase (CODH), mimicking its inner and outer spheres is a promising strategy in CO2 reduction catalyst design. However, artificial CODH‐like catalysts are generally limited to the inner sphere effect and only applicable in organic solvents or for electrocatalysis. Herein, an aqueous CODH mimic with both inner and outer spheres for photocatalysis is reported. In this polymeric unimolecular catalyst, the inner sphere is composed of cobalt porphyrin with four appended amido groups and the outer sphere consists of four poly(2‐(dimethylamino)ethyl methacrylate) (PDMAEMA) arms. Upon visible light irradiation (λ >420 nm), the as‐prepared catalyst exhibits a turnover number (TONCO) of 1731.2 in the reduction of CO2 into CO, which is comparable to most reported molecular catalysts in aqueous solution. The mechanism studies indicate that, in this water‐dispersible and structurally well‐defined CODH mimic, the cobalt porphyrin core serves as the catalysis center and the amido groups function as hydrogen‐bonding pillars helping to stabilize the CO2 adduct intermediate, whereas the PDMAEMA shell renders both water solubility and a CO2 reservoir through reversibly capturing of CO2. The present work has clarified the significance of coordination sphere effects for improving the aqueous photocatalytic CO2 reduction performance of CODH mimics. [ABSTRACT FROM AUTHOR]

Conservation of crop wild relatives is critical for plant breeding and food security. The lack of clarity on the genetic factors that lead to endangered status or extinction create difficulties when attempting to develop concrete recommendations for conserving a citrus wild relative: the wild relatives of crops. Here, we evaluate the conservation of wild kumquat (Fortunella hindsii) using genomic, geographical, environmental, and phenotypic data, and forward simulations. Genome resequencing data from 73 accessions from the Fortunella genus were combined to investigate population structure, demography, inbreeding, introgression, and genetic load. Population structure was correlated with reproductive type (i.e., sexual and apomictic) and with a significant differentiation within the sexually reproducing population. The effective population size for one of the sexually reproducing subpopulations has recently declined to ~1,000, resulting in high levels of inbreeding. In particular, we found that 58% of the ecological niche overlapped between wild and cultivated populations and that there was extensive introgression into wild samples from cultivated populations. Interestingly, the introgression pattern and accumulation of genetic load may be influenced by the type of reproduction. In wild apomictic samples, the introgressed regions were primarily heterozygous, and genome-wide deleterious variants were hidden in the heterozygous state. In contrast, wild sexually reproducing samples carried a higher recessive deleterious burden. Furthermore, we also found that sexually reproducing samples were self-incompatible, which prevented the reduction of genetic diversity by selfing. Our population genomic analyses provide specific recommendations for distinct reproductive types and monitoring during conservation. This study highlights the genomic landscape of a wild relative of citrus and provides recommendations for the conservation of crop wild relatives. Author summary: Conservation genomics offers a comprehensive approach to understand the underlying genetic and environmental factors affecting the conservation of species. Despite its importance, the conservation genomics of most crop wild relatives remains poorly understood. In this study, we investigated the population fragmentation, inbreeding, gene flow, and genetic load of a citrus wild relative, Fortunella hindsii, using a combination of genomic, geographical, environmental, and phenotypic data, as well as forward simulations. Fortunella hindsii, listed on the registry of National Key Protected Wild Plants in China, has two types of reproduction, sexual and apomictic. Conservation genomics provided insights into the genetic diversity and structure, which are critical for developing effective conservation strategies. Our analysis also helped to assess the risks of hybridization and introgression from cultivated to wild populations. We found that different patterns of introgression and genetic load may be influenced by reproductive type; for example, deleterious variants may hide in the heterozygous state in apomictic populations. Sexually reproducing samples with the self-incompatibility mechanism can prevent rapid loss of genetic diversity caused by selfing. This study serves as an example of conservation genomics and the importance of utilizing important wild relatives of crops to inform broader conservation efforts. [ABSTRACT FROM AUTHOR]

Supramolecular self‐assembly is a promising strategy for stabilizing the photo‐sensitive components in photocatalysis. However, the underlying correlation between the enhanced photostability and supramolecular structure at the molecular level has not yet been fully understood. Herein, we develop a biomimetic vesicular membrane‐based polyporphyrin photocatalyst exhibiting excellent photocatalytic stability with at least activity time of 240 h in hydrogen generation. Time‐domain ab initio modelling together with transient absorption spectroscopy, visual frontier orbitals and Gibbs free energy calculation disclose that the ordered aggregation of porphyrin units in the vesicle membrane facilitates "hot" electron relaxation and the rapid dissipation of photo‐generated charges, thereby contributing to the longevity. This work deepens the molecular‐level understanding on photostability and photocatalytic mechanism of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

Supramolecular self‐assembly is a promising strategy for stabilizing the photo‐sensitive components in photocatalysis. However, the underlying correlation between the enhanced photostability and supramolecular structure at the molecular level has not yet been fully understood. Herein, we develop a biomimetic vesicular membrane‐based polyporphyrin photocatalyst exhibiting excellent photocatalytic stability with at least activity time of 240 h in hydrogen generation. Time‐domain ab initio modelling together with transient absorption spectroscopy, visual frontier orbitals and Gibbs free energy calculation disclose that the ordered aggregation of porphyrin units in the vesicle membrane facilitates "hot" electron relaxation and the rapid dissipation of photo‐generated charges, thereby contributing to the longevity. This work deepens the molecular‐level understanding on photostability and photocatalytic mechanism of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa is a bacterium that infects crops like grapevines, coffee, almonds, citrus and olives. There is little understanding of the genes that contribute to plant resistance, the genomic architecture of resistance, and the potential role of climate in shaping resistance, in part because major crops like grapevines (Vitis vinifera) are not resistant to the bacterium. Here we study a wild grapevine species, V. arizonica, that segregates for resistance. Using genome-wide association, we identify candidate resistance genes. Resistance-associated kmers are shared with a sister species of V. arizonica but not with more distant species, suggesting that resistance evolved more than once. Finally, resistance is climate dependent, because individuals from low (< 10 °C) temperature locations in the wettest quarter were typically susceptible to infection, likely reflecting a lack of pathogen pressure in colder climates. In fact, climate is as effective a predictor of resistance phenotypes as some genetic markers. We extend our climate observations to additional crops, predicting that increased pathogen pressure is more likely for grapevines and almonds than some other susceptible crops. Potential resistance genes for Xylella fastidiosa in wild grapes are identified and resistance is shown to be climate dependent. [ABSTRACT FROM AUTHOR]

Lithium/thionyl chloride (Li/SOCl2) primary batteries are appealing power solutions because of their remarkable electrochemical performances. However, their mass applications are hindered by the challenges in sustainability, cost and safety concerns owing to the employed Li chemistry. Here, magnesium (Mg) chemistry is shown as a promising alternative through synergistic optimization of electrolyte solvation and electrode reaction kinetics. The first Mg/SOCl2 primary battery yields surprisingly high specific capacities up to ≈14 000 mAh g−1 at a decent discharge voltage of ≈1.67 V, which outperforms the state‐of‐the‐art Mg‐based primary batteries. In addition, it retains almost 100% of the original capacity after 20‐day reservation. The impressive battery performances are originated from the stabilized MgCl2 formation on high‐surface‐area carbon cathode and suppressed Mg anode corrosion via the Mg‐induced solvation effect. Mg/SOCl2 primary batteries are promising candidates for low‐cost and recyclable power supplies, and they thus open new avenues for the development of sustainable battery chemistries. [ABSTRACT FROM AUTHOR]

This study presents interesting self‐assembly of peapod‐like micrometer tubes from a planet‐satellite‐type supramolecular megamer, which was constructed through the specific host–guest molecular recognition between azobenzene (AZO)‐functionalized hyperbranched poly(ethyl‐3‐oxetanemethanol)‐star‐poly(ethylene oxide) (HSP‐AZO) and β‐cyclodextrin(CD)‐based hydrophilic hyperbranched polyglycerol (CD‐g‐HPG). A peapod‐like structure with micrometer‐sized tube as the pod and vesicles encapsulated inside as the peas was formed through sequential vesicle entosis, linear association, and fusion processes. Dissipative particle dynamics (DPD) simulations support the structural possibility of the supramolecular peapod formation and its mechanism. UV light irradiation could lead to the disassembly of the peapod‐like structure. This study expands the family of supramolecular polymers and opens a new avenue to develop bioinspired complex hierarchical nanoarchitectures at the microscopic level. [ABSTRACT FROM AUTHOR]

This study presents interesting self‐assembly of peapod‐like micrometer tubes from a planet‐satellite‐type supramolecular megamer, which was constructed through the specific host–guest molecular recognition between azobenzene (AZO)‐functionalized hyperbranched poly(ethyl‐3‐oxetanemethanol)‐star‐poly(ethylene oxide) (HSP‐AZO) and β‐cyclodextrin(CD)‐based hydrophilic hyperbranched polyglycerol (CD‐g‐HPG). A peapod‐like structure with micrometer‐sized tube as the pod and vesicles encapsulated inside as the peas was formed through sequential vesicle entosis, linear association, and fusion processes. Dissipative particle dynamics (DPD) simulations support the structural possibility of the supramolecular peapod formation and its mechanism. UV light irradiation could lead to the disassembly of the peapod‐like structure. This study expands the family of supramolecular polymers and opens a new avenue to develop bioinspired complex hierarchical nanoarchitectures at the microscopic level. [ABSTRACT FROM AUTHOR]

Leukocytes of the mother sow were also shown a few GFP positive cells, and the second column showed that most of these GFP positive cells were CD3+ cells. We found that 0.043% of GFP positive cells were present in PBMC and 88.3% of these cells were CD3 SP + sp T cells (Figure 1G). To find out whether foetal cells could also circulate through the blood to other organs of the surrogates, we euthanized the sows after delivery and examined the presence of GFP positive cells in other organs by freezing sections (Method S5). The presence of a tiny population of foreign cells or DNA in an organism is known as microchimerism. [Extracted from the article]

Apomixis, or asexual seed formation, is prevalent in Citrinae via a mechanism termed nucellar or adventitious embryony. Here, multiple embryos of a maternal genotype form directly from nucellar cells in the ovule and can outcompete the developing zygotic embryo as they utilize the sexually derived endosperm for growth. Whilst nucellar embryony enables the propagation of clonal plants of maternal genetic constitution, it is also a barrier to effective breeding through hybridization. To address the genetics and evolution of apomixis in Citrinae , a chromosome-level genome of the Hongkong kumquat (Fortunella hindsii) was assembled following a genome-wide variation map including structural variants (SVs) based on 234 Citrinae accessions. This map revealed that hybrid citrus cultivars shelter genome-wide deleterious mutations and SVs into heterozygous states free from recessive selection, which may explain the capability of nucellar embryony in most cultivars during Citrinae diversification. Analyses revealed that parallel evolution may explain the repeated origin of apomixis in different genera of Citrinae. Within Fortunella , we found that apomixis of some varieties originated via introgression. In apomictic Fortunella , the locus associated with apomixis contains the FhRWP gene, encoding an RWP-RK domain-containing protein previously shown to be required for nucellar embryogenesis in Citrus. We found the heterozygous SV in the FhRWP and CitRWP promoters from apomictic Citrus and Fortunella , due to either two or three miniature inverted transposon element (MITE) insertions. A transcription factor, FhARID , encoding an AT-rich interaction domain-containing protein binds to the MITEs in the promoter of apomictic varieties, which facilitates induction of nucellar embryogenesis. This study provides evolutionary genomic and molecular insights into apomixis in Citrinae and has potential ramifications for citrus breeding. [ABSTRACT FROM AUTHOR]

The Grain for Green Program (GGP) is the largest afforestation and reforestation project in China in the early part of this century. To assess carbon sequestration in stands under the GGP in Southwest China, the carbon stocks and their annual changes in the GGP stands in the region were estimated based on the following information: (1) collected data on the annually planted area of each tree species under the GGP in Southwest China from 1999 to 2010; (2) development of empirical growth curves and corresponding carbon estimation models for each species growing in the GPP stands; and (3) parameters associated with the stands such as wood density, biomass expansion factor, carbon fraction and the change rate of soil organic carbon content. Two forest management scenarios were examined: scenario A, with no harvesting, and scenario B, with logging at the customary rotation followed by replanting. The results showed that by the years 2020, 2030, 2040, 2050 and 2060, the expected carbon storage of the GGP stands in Southwest China is 139.58 TgC, 177.50–207.55 TgC, 196.86–259.65 TgC, 240.45–290.62 TgC and 203.22–310.03 TgC (T = 1012), respectively. For the same years, the expected annual change in carbon stocks is 7.96 TgCyr−1, −7.95–5.95 TgCyr−1, −0.10–4.67 TgCyr−1, 4.31–2.24 TgCyr−1 and −0.02–1.75 TgCyr−1, respectively. This indicates that the stands significantly contribute to forest carbon sinks in this region. In 2060, the estimated carbon stocks in the seven major species of GGP stands in Southwest China are 4.16–13.01 TgC for Pinus armandii, 6.30–15.01 TgC for Pinus massoniana, 11.51–13.44 TgC for Cryptomeria fortunei, 15.94–24.13 TgC for Cunninghamia lanceolata, 28.05 TgC for Cupressus spp., 5.32–15.63 TgC for Populus deltoides and 5.87–14.09 TgC for Eucalyptus spp. The carbon stocks in these seven species account for 36.8%–41.4% of the total carbon stocks in all GGP stands over the next 50 years. [ABSTRACT FROM AUTHOR]

The nanostructure of ion channels of thin perfluorosulfonic acid membrane in the catalyst layer plays an important role in determining the efficiency of proton exchange membrane fuel cells. However, it is still unclear at microscopic scale at present time. In this work, by combining molecular dynamics simulation with unsupervised machine learning, the nanostructure of ion channels in the catalyst layer was visualized and quantified, including the size, shape, distribution and connectivity. Then the effects of water content and side chain length on the nanostructure of ion channels in the catalyst layer were revealed. It is shown that the water content has a more important effect than side chain length. As the water content increases and the side chain becomes shorter, the ionic clusters become larger and the bridging region between neighboring ionic clusters becomes wider. Moreover, the shape anisotropy of the ionic clusters becomes slightly smaller with increasing water content. The heterogeneity of the diffusion of water molecules is revealed, which may originate from the spatial limiting effect of the size of ionic clusters, as well as the strong interactions with sulfonate and platinum. It is also found that the jumping of water molecules between neighboring ionic clusters is a rate-limiting step of transport. This study provides a fundamental and comprehensive understanding on the nanostructure of ion channels and related transport properties in the thin PFSA membrane of catalyst layer, which is vital for the design of high-performance proton exchange membranes. [Display omitted] • Ionic clusters in thin PFSA membrane were discerned from one another. • Nanostructure of ion channels in thin PFSA membrane was visualized and quantified. • The jumping of water molecules between neighboring ionic clusters is a key factor in the diffusion. [ABSTRACT FROM AUTHOR]

The cytoskeleton is one of the most important cellular components. Up to now, most of the reported artificial cytoskeletons are based on a gel‐in‐vesicle strategy. Herein, we report a membrane‐bound inward‐growth pathway to prepare cytoskeleton‐like and radially aligned nanofibers grown from capsule membranes to get membrane‐bound artificial cytoskeletons (MACs). The mechanism therein is disclosed through the direct observation of the intermediates in both dried and liquid states. Furthermore, the as‐prepared MACs show a selective disassembly behavior in the presence of reductants: both capsule membranes and MACs can be disassembled or only MACs can be disassembled through the selective introduction of dynamic disulfide bonds (DS) into them and by the switch of ultraviolet (UV) irradiation. The present work provides a new hierarchical self‐assembly way to construct artificial cytoskeletons with controlled compositions and orientations. [ABSTRACT FROM AUTHOR]

The cytoskeleton is one of the most important cellular components. Up to now, most of the reported artificial cytoskeletons are based on a gel‐in‐vesicle strategy. Herein, we report a membrane‐bound inward‐growth pathway to prepare cytoskeleton‐like and radially aligned nanofibers grown from capsule membranes to get membrane‐bound artificial cytoskeletons (MACs). The mechanism therein is disclosed through the direct observation of the intermediates in both dried and liquid states. Furthermore, the as‐prepared MACs show a selective disassembly behavior in the presence of reductants: both capsule membranes and MACs can be disassembled or only MACs can be disassembled through the selective introduction of dynamic disulfide bonds (DS) into them and by the switch of ultraviolet (UV) irradiation. The present work provides a new hierarchical self‐assembly way to construct artificial cytoskeletons with controlled compositions and orientations. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous Zn‐ion batteries (ZIBs) are regarded as one of the most promising devices for the next‐generation energy storage system. However, the uncontrolled dendrite growth on Zn metal anodes and the side hydrogen evolution reaction, which has not yet been well considered, hinder the practical application of these batteries. Herein, a uniform and robust metallic Sb protective layer is designed based on the theoretic calculation and decorated on Zn plate via in situ replacement reaction. Compared with the bare Zn plate, the as‐prepared Zn@Sb electrode provides abundant zincophilic sites for Zn nucleation, and homogenizes the electric field around the Zn anode surface, both of which promote the uniform Zn deposition to achieve a dendrite‐free morphology. Moreover, the Gibbs free energy (∆GH) calculation and in situ characterization demonstrate that hydrogen evolution reaction can be effectively suppressed by the Sb layer. Consequently, Sb‐modified Zn anodes exhibit an ultralow voltage hysteresis of 34 mV and achieve excellent cycling stability over 1000 h with hydrogen‐ and dendrite‐free behaviors. This work provides a facile and effective strategy to suppress both hydrogen evolution reaction and dendrite growth. [ABSTRACT FROM AUTHOR]

Durability is one of the most key problems for the widespread commercialization of proton exchange membrane fuel cells (PEMFCs). Proton exchange membranes (PEMs) are pivotal components of the PEMFCs and their chemical stability is thus an important for the PEMFCs reliability. The incorporation of Ce-based radical quenchers such as ceria in PEMs can obviously alleviate the chemical deterioration of PEMs. Nevertheless, cell performance may decrease due to the presence of Ce-based radical quenchers. Therefore, a trade-off between cell performance and chemical stability of Ce-based radical quenchers containing PEM appears. To solve this issue, we developed a Ce-based metal organic framework Ce-BTC MOF with high radical trapping and proton-conducting properties. The Ce-BTC MOFs are introduced into the PFSA membrane to enhance the chemical stability and proton conductivity of the PFSA membrane. The PFSA/Ce-BTC membrane showed a maximum power density of 1.71 W/cm2 at 75 °C under 80％RH. After OCV test, PFSA/Ce-BTC membrane exhibited a decay of 0.56 mV/h after 120 h; pristine PFSA and Nafion membrane exhibited accelerated decay (for pristine PFSA, 1.72 mV/h; for Nafion membrane, 2.36 mV/h). Therefore, introduction of Ce-BTC MOFs offers an active defence approach to enhance the chemical stability of PEMFCs without sacrificing their cell performance. [Display omitted] • A Ce-based metal organic framework (Ce-BTC MOF) was prepared by solvothermal method. • The Ce-BTC MOF has high radical scavenging and proton-conducting properties. • The fabricated membrane has excellent chemical durability and cell performance. [ABSTRACT FROM AUTHOR]

Abstract: Graft copolymerization of N-vinyl-2-pyrrolidone (NVP) onto 60Co γ-ray pre-irradiated poly (vinylidene fluoride) (PVDF) powder was investigated to find out the relationship between the degree of grafting (DG) and various factors, including monomer concentration, irradiation dose, reaction time, catalyst and so on. The DG can be calculated by comparing the amount of nitrogen element in the resulting copolymer (PVDF-g-PVP) powder with that in PVP on the basis of element analysis. The presence of PVP in the resulting PVDF powder was confirmed by the comparative studies of pristine PVDF and grafted PVDF powder through Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), X-ray photoelectron spectroscopy (XPS), thermo gravimetric analyzer (TGA) and differential scanning calorimetry (DSC), respectively. When the reaction was performed at the monomer concentration of 20% (vol.) and the absorbed dose of 40kGy for 3h in water, the max. DG of 17.7% was obtained. [Copyright &y& Elsevier]

A multi-to-one supramolecular photocatalyst is fabricated by aqueous electrostatic self-assembly of multiple graphene quantum dot (GQD) antennas onto a single-Pt-site porphyrin unimolecular micelle (PtTHPD-UM) catalytic center. Light energy is transferred from GQDs to PtTHPD-UM to catalyze water splitting into hydrogen up to 57 190 μmol g(Pt)−1 h−1 under visible light. [ABSTRACT FROM AUTHOR]

Magnesium alloys are highly sought after as environment-friendly engineering materials for the 21st century. Mg-RE (rare earth) alloys, especially Mg-Gd-(Y)-Zn alloys, have attracted significant interest in the past two decades due to their potential high performances over conventional or commercial magnesium alloys. Recent research has revealed that the LPSO、 β series and γ series phases are the main strengthening phases in Mg-Gd-(Y)-Zn alloys. This article aims to provide a review of recent progress on the transformation of these main strengthening phases in the as-cast Mg-Gd-(Y)-Zn alloys, especially the co-existence of multiple strengthening mechanisms. Further, substantial research recommendations for the future development of high-performance and even ultra-high-strength casting Mg-RE alloys are proposed in terms of casting procedure, heat treatment process, alloying elements, and strength-plasticity trade-off. [ABSTRACT FROM AUTHOR]