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In this work, experiments and comprehensive insights into the proposed covering liquid method to intensify self-preservation effect for methane (CH4) storage are presented. The CH4 hydrate decomposition percentage was 17.6% with the pressure of 0.61 MPa after 12 h at 266.0 K without a covering liquid, which can be reduced to 12.4%, 13.8%, 13.0%, and 8.3% with the pressure of 0.26 MPa, 0.33 MPa, 0.51 MPa, and 0.37 MPa by covering with tetrahydrofuran (THF), cyclopentane (CP), cyclohexane, and n-tetradecane, respectively. When the temperature for CH4 hydrate decomposition was 274.2 K, covering with THF, CP, cyclohexane, and n-tetradecane failed to inhibit CH4 hydrate decomposition. The results suggested that the covering liquid may form a new solid layer (a hydrate layer or other solidified layer) around the CH4 hydrate, which inhibit CH4 transfer below the freezing point of water. However, the new solid layer cannot resist the fast transfer of CH4 from decomposed CH4 hydrate above the freezing point of water. The same phenomenon was also observed in a sodium dodecyl sulfonate (SDS)-dry solution CH4 hydrate formation system. Therefore, the covering method can only intensify the self-preservation effect below the freezing point of water, but cannot generate a self-preservation effect.

Niobium carbide composite coatings were prepared on titanium alloy surface by plasma spraying NbC–Al2O3, Nb–SiC and Nb–SiC–Al composite powders, respectively. The phase composition, microstructure and formation mechanism of the three composite coatings were analyzed and their microhardness, toughness and scratch resistance were compared. The phases of the NbC–Al2O3 system did not change during the plasma spraying process, and new phases (Nb2C, NbC and Nb3Si) were formed in the Nb–SiC and Nb–SiC–Al systems. TEM results of the Nb–SiC composite coating indicate that the new phases nanocrystalline Nb2C, submicron NbC and nanocrystalline Nb3Si were formed during the plasma spraying process. Compared with the NbC–Al2O3 composite coating, the microstructure of the Nb–SiC and the Nb–SiC–Al composite coatings were uniform, and the porosity were relatively low, and the hardness was higher. The Nb–SiC–Al composite coating was denser than the Nb–SiC composite coating, the lamellar structure was obvious and the number of pores in the coating was the least, which is attributed to the better molten state of the composite powder by the addition of the Al to the Nb–SiC system. The Nb–SiC–Al composite coating had better toughness and scratch resistance.

The development of helicene molecules with significant chiroptical responses covering a broad range of the visible spectrum is highly desirable for chiral optoelectronic applications; however, their absorption dissymmetry factors (gabs) have been mostly lower than 0.01. In this work, we report unprecedented B,N-embedded double hetero[7]helicenes with nonbonded B and N atoms, which exhibit excellent chiroptical properties, such as strong chiroptical activities from 300 to 700 nm, record high gabs up to 0.033 in the visible spectral range, and tunable circularly polarized luminescence (CPL) from red to near-infrared regions (600 ~ 800 nm) with high photoluminescence quantum yields (PLQYs) up to 100%. As revealed by theoretical analyses, the high gabs values are related to the separate molecular orbital distributions owing to the incorporation of nonbonded B and N atoms. The new type of B,N-embedded double heterohelicenes opens up an appealing avenue to the future exploitation of high-performance chiroptical materials.

The rapid warming of the Arctic has led to permafrost degradation, accelerating the transport of terrestrial materials by rivers. The quantitative assessment of riverine nutrients and total suspended solids (TSS) flux is important to clarify the land–ocean connections in the Arctic. However, much is unknown about the estimates of these components from direct measurements in the Arctic rivers and the response of the components to permafrost degradation. Here, we report the results from the Arctic Great Rivers Observatory (Arctic-GRO) for the six major Arctic rivers (Yenisey, Lena, Ob’, Mackenzie, Yukon, and Kolyma) to investigate the riverine exports of TSS, total dissolved nitrogen (TDN), nitrate ( NO 3 − ), bicarbonate ( HCO 3 − ), total dissolved phosphorus (TDP), and phosphate ( PO 4 3 − ). The results showed that from 2004 to 2017, the annual TSS, TDN, and NO 3 − exports to the Arctic Ocean were approximately 106,026 Gg, 692 Gg, and 130 Gg, respectively, and the HCO 3 − , TDP, and PO 4 3 − exports were approximately 79,092 Gg, 32 Gg, and 18 Gg, respectively. There were remarkable variations in component concentrations and fluxes between seasons. More than 80% of the TDN, TDP, PO 4 3 − , and TSS exports mainly occurred in spring and summer, and a high HCO 3 − flux was recorded in summer, while a high NO 3 − flux in some rivers occurred in winter. The active layer thickness was significantly positively correlated with the annual TDN, NO 3 − , and HCO 3 − exports. In addition, the HCO 3 − flux of the six Arctic rivers increased by 247 Gg per year during 2004–2017. The positive relationship between the active layer thickness and river discharge indicates that permafrost degradation accelerated riverine carbonate, nitrogen, and phosphorus exports. This study demonstrates that riverine exports play an important role both in the Arctic terrestrial and marine ecosystems, and permafrost degradation will likely increase the riverine material exports to the ocean.

A novel type of polyacid corrosion inhibitor (PCI) was synthesized from the residue of 2-vinylpyridine, which could reduce the cost of hazardous waste disposal in production enterprises, and solve the environmental pollution caused by residue. Herein, the components of the residue were analyzed and a special solvent is selected to dissolve it. Then, synergistic experiments of the residual solution with different inhibitor were carried out to select the corrosion inhibitor components, and the optimal ratio of each component was determined by orthogonal experiments. The performance of PCI was estimated by weight loss method, and its electrochemical type was detected by electrochemical experiments. It indicated that the main components of 2-vinylpyridine residue are pyridine derivatives and hydrocarbons. The developed PCI is composed by four components, which could be suitable for HCl, citric acid, sulfamic acid, other acid systems, and has good corrosion inhibition effect on carbon steel, brass, and other materials. The corrosion rate of N80 carbon steel can reach to 0.5491 g m−2 h−1 at 60 ℃ in 5% HCl, which fully meets the requirements of China national standards. The electrochemical polarization curve showed that PCI is a kind of highly effective mixed inhibitor, which can inhibit both cathode and anode simultaneously.

Acepleiadylene (APD), a nonbenzenoid nonalternant isomer of pyrene, exhibits different electronic properties from pyrene, but has been rarely studied since its first synthesis in 1956, probably due to the difficulties in synthesis and further derivatization. In this work, we revisited this long-known compound and developed a new two-step synthetic route to efficiently access APD on the gram scale. Theoretical and experimental characterizations elucidated the unique properties of APD as compared with its benzenoid isomer pyrene, particularly revealing its dipolar structure with a narrow optical gap. The functionalization of APD was demonstrated for the first time, providing doubly brominated APD as a key precursor for further π-extension. As a proof of concept, a π-extended APD and a cyclotrimer nanographene (C48H24) were constructed, opening up new avenues to nonbenzenoid nanographenes with low HOMO-LUMO gaps.

To investigate the effects of incorporating gas and the associated influencing factors on polymer melt, a method of evaluating the gas-laden ability using modified rheometric measurements was proposed. In this study, common and widely used thermoplastic materials—polypropylene (PP) and high-density polyethylene (HDPE), and their blends with different weight ratios—were selected, and the rheological properties of neat melt and gas-laden melts were tested using a modified torque rheometer. The foamed samples were also produced using a regular injection-molding machine, and the foamed morphology was examined by scanning electron microscope (SEM). The comparison of rheological curves of neat melt and gas-laden melt indicated that the incorporation of gas influenced the rheological properties of the gas-laden polymer melts as evidenced by a decrease of zero-rotational torque and an increase in the melt flow index. The results also suggested that the gas-laden ability of polymer melt could be evaluated quantitatively by the decay (due to desorption) of gas using the modified rheological measurement method. This study also demonstrated that the gas-laden ability can be used to predict the foaming behavior of polymer melts.

Selective conversion of methane to value-added products with high activity and high selectivity to the target products under mild reaction condition remains a great challenge. Herein, bicomponent IrFe supported on ZSM-5 (IrFe/Z-5) was investigated for the selective oxidation of methane. Compared with the 0.7Fe/Z-5 catalyst, the 0.1Ir-0.6Fe/Z-5 exhibited much higher oxygenate yield (3192 vs 971 mu mol/g/h). In addition, higher H2O2 utilization efficiency was obtained, and the selectivity toward formic acid was enhanced from 54% to 71.3%. It was found that the activation of the C-H bond was improved by the introduction of Ir single atoms. The superior catalytic performance of 0.1Ir-0.6Fe/Z-5 can be attributed to the synergistic effect between Ir and Fe species with high C-H bond activation capacity and high H2O2 utilization efficiency.

Noble metal nanoparticles (NMNPs) with excellent catalytic activity and stability play an important role in the field of environmental governance. A uniform distribution and a strong binding force with the carriers of the noble metal nanoparticles are important, but avoidance of the use of additional reducing agents is a promising direction of research. Herein, 2D ultrathin surfactant-encapsulating polyoxometalate (SEP) nanosheets constructed by the self-assembly of dodecyldimethylammonium bromide (DODA) and molybdophosphate (H3PMo12O40, PMo12) are designed to be versatile carriers for Ag nanoparticles. Under the synergistic effect of the well-arranged PMo12 units, encapsulating hydrophobic oleic acid (OA) and reductive molybdophosphate under Xe lamp irradiation, the silver oleate (AgOA)-derived Ag nanoparticles (5 ± 2 nm) are monodispersed on the DODA-PMo12 assemblies and form the Agx/DODA-PMo12 composite. The optimized Ag4.89/DODA-PMo12 composite exhibits high catalytic activity and stability in the degradation of 4-nitrophenol (4-NP), which reaches a superior rate constant of 6.49 × 10-3 s-1 and without significant deterioration after three recycles. This technique can be facilely promoted to other noble metal nanoparticles with excellent catalytic activity and stability.

It is significant to monitor the thickness change of commercial Li-ion pouch cells that are assembled from Si-based electrodes and layered cathodes since the volume variation is critically linked with kinetic reaction mechanism and chemomechanical degradation. In this work, the single-point and full-field measurements are conducted on the thickness evolution of SiOx/C-graphite/lithium nickel-cobalt-aluminum oxide (SiOx-G/NCA) batteries. It is found that an abnormal overshoot that has been rarely observed in the previous studies appears at the beginning of discharge, which is believed to be the combined results between the rapid expansion of NCA and the contraction of graphite related to the state of charge (SOC). Compared with the results of single-point measurement, the spatial displacement distribution obtained from three-dimensional (3D) scanning suggests the full-field thickness evolution of the entire cell scale, which is more feasible and efficient to provide full-field information for supporting pouch cell design and pack integration.

Based on morphological and molecular evidence, Luisia yunnanensis (Epidendroideae, Orchidaceae), a new species from Yunnan, China, is described and illustrated. A detailed comparison between the newly discovered orchid and other members of Luisia is presented. Molecular analysis of nrITS and plastid DNA (matK, rbcL) sequence data show that L. yunnanensis is sister to L. filiformis with strong support.

Temporary plugging agent (TPA) is widely used in many fields of petroleum reservoir drilling and production, such as temporary plugging while drilling and petroleum well stimulation by diverting in acidizing or fracturing operations. The commonly used TPA mainly includes hard particles, fibers, gels, and composite systems. However, current particles have many limitations in applications, such as insufficient plugging strength and slow degradation rate. In this paper, a degradable pre-formed particle gel (DPPG) was developed. Experimental results show that the DPPG has an excellent static swelling effect and self-degradation performance. With a decrease in the concentration of total monomers or cross-linker, the swelling volume of the synthesized DPPG gradually increases. However, the entire self-degradation time gradually decreases. The increase in 2-acrylamide-2-methylpropanesulfonic acid (AMPS) in the DPPG composition can significantly increase its swelling ratio and shorten the self-degradation time. Moreover, DPPG has excellent high-temperature resistance (150 °C) and high-salinity resistance (200,000 mg/L NaCl). Core displacement results show that the DPPG has a perfect plugging effect in the porous media (the plugging pressure gradient was as high as 21.12 MPa), and the damage to the formation after degradation is incredibly minor. Therefore, the DPPG can be used as an up-and-coming TPA in oil fields.

As an environmental protection fuel, methanol is widely used in national economy. The tremendous price fluctuation of methanol makes risk avoidance an important issue. However, traditional normal h...

With the carbonization at an elevated temperature, high aromaticity of a precursor for porous carbons was traditionally thought to be crucial for the resultant perfect textural properties and ideal application performances of the porous carbons. Thus, many efforts have been done to search or to artificially prepare the polymer precursors with higher aromaticity to generate more satisfying porous carbons. However, an antiempirical case was found in this study. The copolymerization between 1,3,5-tris(chloromethyl)-2,4,6-trimethylbenzene (TCM) and cyclohexane-1,4-diamine was successfully implemented to get a polymer code-named NUT-40, in which half of the ring structures are nonaromatic, while N-doped porous carbons (NDPCs) with better textural properties (e.g., SBET = 1363 m2 g−1 for NDPC-600) and competitive CO2 capture abilities (e.g., CO2 capacity = 4.3 mmol g−1 at 25 °C and 1 bar for NDPC-600) were generated from the NUT-40, compared with the NDPC counterparts derived from the NUT-4 in a previous study (e.g., SBET = 958 m2 g−1 and CO2 capacity = 3.8 mmol g−1 at 25 °C and 1 bar for NDPC-600), in which TCM and ursol were employed as the monomers instead, and thus the ring structures in the NUT-4 was fully aromatic. With first-principle and molecular dynamics simulations, it was demonstrated that the embryo pore structure in the NUT-40 molecule can be more easily maintained during the carbonization than that of the NUT-4, which finally improves the surface area and porosity of the NUT-40 generated NDPCs.

We report a series of colorable zeolitic imidazolate framework (ZIF)-based nanomaterials prepared by encapsulating starches (amylopectin, dextrin, or amylose) or tannic acid in the frameworks of ZIFs and first applied them in colorimetric assay of microRNA/DNA by adding I2/KI or FeCl3 solutions as chromogenic reagents. We found that iodine molecules can lead to rapid degradation of the ZIF-8 framework, while ZIF-90 remains stable. Therefore, ZIF-90 was selected for encapsulating the starches or tannic acid, and then assembled with polyethylenimine (PEI) and aptamers of microRNA/DNA. After interacting with the target microRNA/DNA, the aptamers (Ap) move away from the surface of the prepared Ap-starch@ZIF-90 or Ap-tan@ZIF-90, and the I2/KI or FeCl3 solution is added into the system to interact the starches (amylopectin, dextrin, or amylose) or tannic acid to generate different colors. According to the absorbance spectra, good linear correlations between the logarithm of absorbance intensity and the concentration of microRNA (1-180 nM) can be observed, and the naked eye can distinguish the change from ∼60 to ∼180 nM with a concentration gradient of 20 nM. A similar colorimetric assay ability for pathogenic bacteria can also be realized by detecting the gene fragments IS200 and eaeA. The detection limits can be potentially optimized by changing the amount of adsorbed PEI and aptamers on the surface of Ap-starch@ZIF-90 (or Ap-tan@ZIF-90) nanoparticles. This method could be a promising alternative for simple and cost-effective assay of microRNA/DNA.

Increased application of the pyrethroid insecticide deltamethrin has adverse effects on the cardiac system and neurobehavior on the non-target organisms, which has raised the public's attention. Because of spermidine and melatonin considered to have cardioprotective and neuroprotective characteristics, zebrafish were utilized as the model organism to explore the protective effects of spermidine and melatonin against deltamethrin-induced toxicity. We tested the neurobehavior of zebrafish larvae through a rest/wake behavior assay, and evaluated the levels of the expression of Scn5lab, gata4, nkx2.5, hcrt, hcrtr, and aanat2 by qRT-PCR. Besides that cmlc2 was evaluated by whole-mount in situ hybridization. Results have shown that compared with control group, 0.025 mg/L deltamethrin could significantly disturb the cardiac development, downregulating the expression of Scn5lab and transcriptional factors gata4 and nkx2.5, disturbing cardiac looping, resulting in defects in cardiac morphology and function. Moreover, deltamethrin could alter the expression levels of rest/wake genes and cause hyperactivity in zebrafish larvae. Besides, compared with deltamethrin group, the exogenous 0.01 mg/L spermidine and 0.232 mg/L melatonin could significantly rescue the adverse effects of deltamethrin on the cardiac system and neurobehavior in zebrafish. This indicated that spermidine and melatonin have neuroprotective and cardioprotective effects against deltamethrin-induced adverse effects in zebrafish.

Polycystic ovary syndrome (PCOS) causes anovulatory infertility in women of reproductive age, but etiopathogenesis of PCOS remains undetermined. Taurine up-regulated 1 (TUG1), an evolutionarily con...

Glutathione (GSH), the most abundant nonprotein thiol found in living organisms, are involved in the etiology and progression of many human diseases including cancer. So, monitoring changes of cellular GSH levels has an important guiding significance. To date, however, majority of probes can only qualitatively detect GSH in living cells. Herein, with coumarin as the read-out fluorophore and Michael addition as the sensing mechanism, six fluorescent probes were designed and synthesized. Among them, RP-2 exhibited a reversible and extremely fast response toward GSH (half time: ∼3 s), which endowed RP-2 the capacity of real-time imaging. Among the reversible probes based on Michael addition, RP-2 had both the largest forward and reverse rate constants thus far. The reaction between RP-2 and GSH was studied in detail by density functional theory and fluorescence spectroscopy. Real-time imaging of GSH levels in living cells was achieved with a temporal resolution of seconds. To simplify the processing of images, a program was developed and validated. RP-2 was expected to serve as a new fluorescent imaging tool to understand the function of intracellular GSH in the future.

Spermatogenesis depends on precise epigenetic and genetic regulation of spermatogonial stem cells (SSCs). However, it remains largely unknown about the roles and mechanisms of small noncoding RNA in regulating the self-renewal and apoptosis of human SSCs. Notably, we have found that Homo sapiens-microRNA (hsa-miR)-1908-3p is expressed at a higher level in human spermatogonia than pachytene spermatocytes. MiR-1908-3p stimulated cell proliferation and DNA synthesis of the human SSC line. Allophycocyanin (APC) Annexin V and propidium iodide staining, determined by flow cytometric analysis and TUNEL assays, showed that miR-1908-3p inhibited early and late apoptosis of the human SSC line. Furthermore, Kruppel-like factor 2 (KLF2) was predicted and verified as the target of miR-1908-3p, and, significantly, KLF2 silencing resulted in the increase of proliferation and DNA synthesis, as well as reduction of apoptosis of the human SSC line. Moreover, KLF2 silencing ameliorated the decrease in the proliferation and DNA synthesis and the enhancement in the apoptosis of the human SSC line caused by miR-1908-3p inhibition. Collectively, these results implicate that miR-1908-3p stimulates the self-renewal and suppresses the apoptosis of human SSCs by targeting KLF2. This study thus provides a novel epigenetic regulatory mechanism underlying the fate determinations of human SSCs, and it offers new endogenous targets for treating male infertility., Graphical Abstract, This study has demonstrated that miR-1908-3p stimulates the self-renewal and suppresses the apoptosis of human spermatogonial stem cells (SSCs) by targeting KLF2, which provides a novel epigenetic regulatory mechanism underlying the fate determinations of human SSCs and offers new targets for the diagnosis and treatment of male infertility.

Gamma-ray (gamma-ray) irradiation was introduced into zeolite synthesis. The crystallization process of zeolite NaA, NaY, Silicalite-1, and ZSM-5 were greatly accelerated. The crystallization time of NaA zeolite was significantly decreased to 18 h under gamma-ray irradiation at 20 degrees C, while more than 102 h was needed for the conventional process. Unexpectedly, more mesopores were created during this process, and thus the adsorption capacity of CO2 increased by 6-fold compared to the NaA prepared without gamma-ray irradiation. Solid experimental evidence and density function theory (DFT) calculations demonstrated that hydroxyl free radicals (OH*) generated by gamma-rays accelerated the crystallization of zeolite NaA. Besides NaA, mesoporous ZSM-5 with MFI topology was also successfully synthesized under gamma-ray irradiation, which possessed excellent catalytic performance for methanol conversion, suggesting the universality of this new synthetic strategy for various zeolites.

The utilization of carbon dioxide (CO2) as a nontoxic, abundant, economical and renewable C1 building block for the production of valuable organic chemicals can contribute to a more sustainable chemical industry. In the chemical process using CO2 as a raw material, the synthesis of degradable aliphatic polycarbonates by alternating copolymerization with epoxides has attracted widespread attention. Notably, aliphatic polycarbonates with biocompatibility and biodegradability have gradually attracted great attention in the field of biomedicine in recent decades, since Inoue and co-workers first reported the copolymerization of CO2 and epoxides to produce biodegradable CO2-based polycarbonates by using heterogeneous catalyst in 1969. This method used non-toxic and inexpensive CO2 to replace the highly toxic phosgene in the traditional polycondensation as carbonylation reagent. Since then, many heterogeneous and homogeneous catalysts systems have been developed for this copolymerization. However, the commercial applications of aliphatic polycarbonates have very limited due to their poor thermal stability and the mechanical properties in comparison with polyolefins. Recently, the binary or bifunctional catalyst based on metal-salen complexes was found to be very efficient for this transformation in immortal polymerization mode, affording various polycarbonates with complete alternating nature, and excellent region- and stereo-selectivity. Along with the discovery of these highly stereoregular catalyst systems that can generate copolymers with high stereoregularity, study on the regiochemistry of epoxides ring-opening during the copolymerization and the stereochemistry of the carbonate unit sequence in the polymer main chain was also reported. The stereochemistry of a polymer significantly affects its physical property. For biodegradable polymers, e.g., polylactide, the degradation rate of isotactic polymers is much slower than that of amorphous polymers due to the orderly arrangement of building units in the former. Additionally, the relative stereochemistry in a polymeric chain also bears a memory of the reaction pathway leading to its formation. Therefore, the assignment of the stereochemistry information on a polymer chain is beneficial for understanding the polymerization mechanism and further designing more efficient catalyst systems. The microstructure information of a polymer can be obtained by analyzing its NMR spectrum. However, since the difference in chemical shifts of the same atom in different stereochemical environments is very small, it is quite difficult to assign the nuclear magnetic signals of polycarbonates. The signals of carbonyl and methine regions in the main chain in the 13C NMR spectra are significantly affected by stereochemistry of polycarbonates. As a consequence, the chemical shift and split of carbonyl and methane in the 13C NMR spectra are used to characterize the microstructure of polycarbonates. The accurate microstructure analysis of a polymer is performed by synthesizing the corresponding model oligomers and analysis of their 13C NMR spectra. In the present contribution, four kinds of model compounds of poly(2,3-butene carbonate): isotactic and syndiotactic tetramers and octamers, were synthesized by the use of chiral 2,3-butanediols as starting materials and triphosgene as carbonylation reagent, which not only avoided the degradation to cyclic carbonate during synthesis but also ensured a fast and reliable increase in the number of oligomer units. By comparing the signals in the 13C NMR spectra of steroregular oligomers, it could be concluded that the signals at 154.12, 75.23 and 15.71 ppm were attributed to carbonyl, methine and methyl of isotactic polymer, respectivey, while the signals at 154.09, 75.07 and 15.51 ppm were assigned to carbonyl, methine and methyl of syndiotactic polymer, respectively.

Intrinsically heat-sealable polyimides with atomic oxygen (AO) resistance (ARPIs) were synthesized from 2,3,3′,4′-oxydiphthalic anhydride (aODPA), 2,5-bis[(4-aminophenoxy)phenyl]diphenylphosphine oxide (BADPO), and para-phenylenediamine (PDA). The effects of the molecular structure and diamine ratio were investigated on the properties of the ARPI, including mechanical property, thermal property, heat sealability, and AO resistance. Heat sealability and AO resistance were realized for the ARPI film by combining the asymmetry of the aODPA moiety and the passivated layer forming characteristic of diphenylphosphine phosphine oxide group. Meanwhile, the deficiency of low mechanical strength and thermal resistance, commonly existing in a completely BADPO-derived polyimide system, was remedied effectively by the higher reactivity and rigidity of PDA.

Wood vinegar (WV) is a common agricultural additive used for treatment of soil and stimulation of plant growth. Phosphate rock powder (PR), coal fly ash (CFA), zeolite (ZE) and bentonite (BE) are the common adsorbents for heavy (loid) metals (HMLs)-contaminated soil treatment. The present study focused on the effect of desorption of Pb(II), Cd(II) and As(III) from adsorbents in the presence of WV. The experimental results revealed that the removal fractions of HMLs from adsorbents gradually decreased and then remained steady with the increase of dilution ratios of WV. Subsequently, the optimal additive concentration of WV on different adsorbents was obtained. The experiment results revealed that acetic acid was the dominating component in WV affecting adsorption capacities of adsorbents for HMLs. Moreover, the research took the first time to discover that the addition of WV effectively modified the structure of adsorbents to improve adsorption capacities for HMLs. Given the advantages of low cost and green products of WV, this study not only provided an effective guidance for rational management of agricultural and environmental safety, but paved a new path to modify the structure of adsorbents for better adsorption capacities for HMLs via addition of WV.

A characteristic feature of phytopathogenic Xanthomonas bacteria is the production of yellow membrane-bound pigments called xanthomonadins. Previous studies showed that 3-hydroxybenzoic acid (3-HBA) was a xanthomonadin biosynthetic intermediate and also, that it had a signaling role. The question of whether the structural isomers 4-HBA and 2-HBA (salicylic acid) have any role in xanthomonadin biosynthesis remained unclear. In this study, we have selectively eliminated 3-HBA, 4-HBA, or the production of both by expression of the mhb, pobA, and pchAB gene clusters in the Xanthomonas campestris pv. campestris strain XC1. The resulting strains were different in pigmentation, virulence factor production, and virulence. These results suggest that both 3-HBA and 4-HBA are involved in xanthomonadin biosynthesis. When both 3-HBA and 4-HBA are present, X. campestris pv. campestris prefers 3-HBA for Xanthomonadin-A biosynthesis; the 3-HBA–derived Xanthomonadin-A was predominant over the 4-HBA–derived xanthomonadin in the wild-type strain XC1. If 3-HBA is not present, then 4-HBA is used for biosynthesis of a structurally uncharacterized Xanthomonadin-B. Salicylic acid had no effect on xanthomonadin biosynthesis. Interference with 3-HBA and 4-HBA biosynthesis also affected X. campestris pv. campestris virulence factor production and reduced virulence in cabbage and Chinese radish. These findings add to our understanding of xanthomonadin biosynthetic mechanisms and further help to elucidate the biological roles of xanthomonadins in X. campestris pv. campestris adaptation and virulence in host plants.

Regeneration and functional recovery of peripheral nerves remain formidable due to the inefficient physical and chemical cues in the available nerve guidance conduits (NGCs). Introducing micropatterns and bioactive substances into the inner wall of NGCs can effectively regulate the behavior of Schwann cells, the elongation of axons, and the phenotype of macrophages, thereby aiding the regeneration of injured nerve. In this study, linear micropatterns with ridges and grooves of 3/3, 5/5, 10/10, and 30/30 μm were created on poly(d,l-lactide-co-caprolactone) (PLCL) films following with surface aminolysis and electrostatic adsorption of graphene oxide (GO) nanosheets. The GO-modified micropatterns could significantly accelerate the collective migration of Schwann cells (SCs) and migration of SCs from their spheroids in vitro. Moreover, the SCs migrated directionally along the stripes with a fastest rate on the 3/3-GO film that had the largest cell adhesion force. The neurites of N2a cells were oriented along the micropatterns, and the macrophages tended to differentiate into the M2 type on the 3/3-GO film judged by the higher expression of Arg 1 and IL-10. The systematic histological and functional assessments of the regenerated nerves at 4 and 8 weeks post-surgery in vivo confirmed that the 3/3-GO NGCs had better performance to promote the nerve regeneration, and the CMAP, NCV, wet weight of gastrocnemius muscle, positive S100β and NF200 area percentages, and average myelinated axon diameter were more close to those of the autograft group at 8 weeks. This type of NGCs thus has a great potential for nerve regeneration.

A novel visible light responsive supramolecualr polymer based on oligo(ethylene glycol) modified BODIPY (BDP), tetramethoxyazobenzene (Azo) and dimeric β-cyclodextrin (β-CD-C) was reported. This polymer demonstrated a tunable aggregation state and morphologies upon green/blue light irradiation in aqueous solution with different water fractions.

The study of half-metallic behavior for transition metal tribromide nanowires is of great significance to the basic research and application in spintronics. We have theoretically investigated the spin transport properties of half-metallic VBr3 nanowires sandwiched between Au(100) electrodes. For the VBr3 nanowire with a length of 24.75 A, the spin-filter efficiency (SFE) achieves 100% when the applied bias is less than 0.4 V. The robustness of half-metallic behavior in VBr3 nanowires is investigated by strains and transition metal doping. The bias range of VBr3 nanowires exhibiting perfect SFE is extended by tensile strains, while it becomes narrower under compressive strains. For VBr3 nanowires doped with Co and Cr, the bias range with ideal SFE is significantly broadened at a low doping concentration. In particular, the VBr3 nanowire doped with 1 Cr atom exhibits perfect SFE in an extremely wide bias range of 0-1.0 V. Our results show that the robustness of half-metallicity of VBr3 nanowires can be improved by tensile strains or certain doping, which provides promising ways for further design of high-performance spintronic devices.

Low-dimensional hybrid lead halides have emerged as new-generation optoelectronic materials due to their compelling photoluminescence properties, and it is significant to explore new type of hybrid halides to diversify the photophysical performances. Herein, by using different kinds of organic cations as structural decoration strategies, we designed two new lead bromides, namely [MeBAPIm]2Pb3Br12 (1) ([MeBAPIm] = 2-methyl-1,3-bis (3-aminopropyl) imidazolidine) and [PMDPTA]2Pb3Br12 (2) (PMDPTA = pentamethyldipropene triamine), via a facile solvothermal reaction. Both the structures of these hybrids contain the same linear [Pb3Br12]6− trimers based on face-shared [PbBr6] octahedrons. Upon UV light excitation, compound 1 displays broadband yellow light emission covering the entire visible spectra with a promising photoluminescence quantum efficiency (PLQE) of 4.57%. The broadband light emission can be ascribed to the self-trapped excitons based on systematical characterizations including steady-state, temperature-dependent and time-resolved emission spectra. The white light emitting device can also be easily fabricated by coating the sample of compound 1 on a blue light chip.

Optomagnonic structures are widely studied in the field of nanophotonics and quantum information science. They are the key platforms for the realization of magnon-mediated microwave to optical transducers in various applications of quantum computing. In order to enhance the coupling between light (photons) and spin waves (magnons), here in this work, we use the Lagrange multiplication method to find the optimum matching condition between the optical whispering-gallery mode and the magnon with Kittle and higher-order modes in microresonators. It is found that the magnon modes located near the edge of the resonator exhibits stronger coupling strength with the optical modes. Numerically, we find the coupling constant can approach 87.6 × 2 π H z in Kittle mode, and 459 × 2 π H z in high-order magnon mode for a yttrium iron garnet (YIG, Y3Fe5O12 ) microdisk cavity with a radius of 300 microns and a thickness of 10 microns. We believe these results may provide an efficient way for enhancing the magneto-optical interaction in the optical devices, which will facilitate the development of magneto-optical control, optical-microwave interaction, and optical nonlinearity.

The model Cu/Zn/Al catalysts with different calcination temperature were prepared by hydrothermal method. The catalysts were characterized by XRD, BET, SEM, CO2-TPD, H2-TPR, TG, CH3OH-TPD and CO2+H2-TPSR. The effect of different calcination temperature on structure, stability and catalytic performance for methanol steam reforming at the conditions of 200-320℃ was also represented. The results of present study show that the different calcination temperature of Cu/Zn/Al catalysts had an obvious influence on the physical characteristics and catalytic performance of the methanol steam reforming.

Background: Xuezhikang, an extract of red yeast rice, effectively lowers fasting blood lipid levels. However, the influence of Xuezhikang on the nonfasting levels of low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) has not been explored in Chinese patients with coronary heart disease (CHD).Methods: Fifty CHD patients were enrolled and randomly divided into two groups (n = 25 each) to receive 1200 mg/d of Xuezhikang or a placebo for six weeks as routine therapy. Blood lipids were repeatedly measured before and after six weeks of treatment at 0, 2, 4 and 6 hour (h) after a standard breakfast containing 800 kcal and 50 g of fat.Results: The serum LDL-C levels significantly decreased, from a fasting level of 3.88 mmol/L to nonfasting levels of 2.99, 2.83 and 3.23 mmol/L at 2, 4 and 6 h, respectively, after breakfast (P < 0.05). However, no significant difference was found in the total cholesterol (TC) levels between the fasting value and values at any nonfasting time points. The serum non-HDL-C level slightly increased from a fasting level of 4.29 mmol/L to nonfasting levels of 4.32, 4.38 and 4.34 mmol/L at 2, 4 and 6 h postprandially, respectively, and the difference reached statistical significance only at 4 and 6 h after breakfast (P < 0.05). No difference was observed in the fasting and nonfasting blood lipids between the two groups at baseline. After six weeks of Xuezhikang treatment, the patients had significantly lower fasting and nonfasting serum levels of LDL-C and non-HDL-C (P < 0.05) than at pretreatment. The LDL-C levels were reduced by 27.8%, 28.1%, 26.2% and 25.3% at 0, 2, 4 and 6 h, respectively, and the non-HDL-C levels were reduced by 27.6%, 28.7%, 29.0% and 28.0% at 0, 2, 4 and 6 h, respectively, after breakfast. No significant difference was found in the percent reductions in the LDL-C and non-HDL-C levels among the four different time points.Conclusions: Six weeks of Xuezhikang treatment significantly decreased LDL-C and non-HDL-C levels, with similar percent reductions in the fasting and nonfasting states in CHD patients, indicating that the percent change in nonfasting LDL-C or non-HDL-C could replace that in the fasting state for evaluation of the efficacy of cholesterol control in CHD patients who are unwilling or unable to fast.

Penicillium oxalicum k10 isolated from soil revealed the hydrolyzing ability of shrimp chitin and antifungal activity against Sclerotinia sclerotiorum. The k10 chitinase was produced from a powder chitin-containing medium and purified by ammonium sulfate precipitation and column chromatography. The purified chitinase showed maximal activity toward colloidal chitin at pH 5 and 40 °C. The enzymatic activity was enhanced by potassium and zinc, and it was inhibited by silver, iron, and copper. The chitinase could convert colloidal chitin to N-acetylglucosamine (GlcNAc), (GlcNAc)2, and (GlcNAc)3, showing that this enzyme had endocleavage and exocleavage activities. In addition, the chitinase prevented the mycelial growth of the phytopathogenic fungi S. sclerotiorum and Mucor circinelloides. These results indicate that k10 is a potential candidate for producing chitinase that could be useful for generating chitooligosaccharides from chitinous waste and functions as a fungicide.

Surfactin is a promising microbial lipopeptide with wide applications in food, environmental, agricultural, and pharmaceutical fields. However, its high cost caused by low productivity largely limits the commercial application. In this study, genome shuffling was employed to improve surfactin production in Bacillus velezensis strain LM3403 via recursive protoplast fusion. RT-qPCR analysis was employed to evaluate the transcriptional variance of surfactin synthase genes and surfactin efflux gene to insight into the variance underlying the recombinant strain. After three rounds of genome shuffling, a high-yield and genetic stable recombinant F34 was obtained, exhibiting dramatic improvement in surfactin production (from 229.60 ± 7.10 mg/L to 908.15 ± 5.65 mg/L) with high proportion of long carbon chain homologues. Scale-up fermentation confirmed that F34 had good growth performance and reached the yield of 917.05 ± 10.25 mg/L in a 30 L fermenter, which was 3.99-fold that of the initial strain. RT-qPCR analysis showed that the transcriptional levels of surfactin synthase genes srfAA and sfp, and surfactin efflux gene swrC in F34 were 8.12-fold, 9.27-fold, and 8.45-fold higher than those of LM3403, respectively. The upregulation of genes were consistent with the high surfactin yield in F34, indicating the increased capability of surfactin biosynthesis and transmember efflux in F34. To our knowledge, this is the first attempt to employ genome shuffling to breeding a B. velezensis strain to improve surfactin yield. The research helps us to understand the mechanisms underlying surfactin overproduction and provide references for further rational strain improvement.

DNA tetrahedral nanomaterials have been widely used in the fields of biosensing, drug delivery, bioimaging and separation analysis because of their high stability, good biocompatibility and easy modification. Through different designs, specific functional molecules can be modified at DNA tetrahedral vertices, DNA tetrahedral cage structures, DNA double helix structures or DNA tetrahedron arms. The advantages of the materials combine well with the specific functions of the active molecules. This paper reviewed the development of DNA nanotechnology, and introduced four different functional modifications of DNA tetrahedron nanomaterials and their research status.

A series of d10 based metal-organic frameworks (MOFs), namely, [Cd2(dpc)(bipy)(H2O)3]n (Ⅰ), {[Cd2(dpc)(bib)(H2O)]·H2O}n (Ⅱ), {[Cd2(dpc)(bitb)1.5(H2O)2]·H2O}n (Ⅲ) (H4dpc = 2-(3′,4′-dicarboxylphenoxy)isophthalic acid, bipy = 4,4′-dipyridyl, bib = 1,4-bis (1-imidazolyl)benzene, bitb = 1,4-bis (imidazol-1-ylmethyl)benzene) have been designed and successfully synthesized using a flexible tetrabasic carboxylic acid along with three ancillary ligands under hydrothermal conditions, which exhibit structural diversities of targeted Cd-MOFs. Single-crystal X-ray diffraction analysis reveals that they contain building units of {CdN1O6} and {CdN1O5} (for I), {CdN1O5} (for II), as well as {CdN2O4} and {CdN5O1} (for Ⅲ), based on which to assemble microporous three-dimensional (3D) frameworks via covalent bonds and/or hydrogen bonds using multiple coordination modes of H4dpc ligand and auxiliary linkers. The solid-state luminescence performances of these Cd-MOFs were investigated at ambient temperature. Furthermore, luminescent sensing responses of Ⅰ-Ⅲ to amino acids and metal cations were systematically explored. Notably, Ⅰ and II may act as potential dual-functional luminescent sensors for Aspartic acid and Cu2+ cations as well as Aspartic acid and Fe3+ cations with high selectivity and sensitivity in aqueous solutions, respectively. The mechanisms of the quenching effect and sensing properties of the as-synthesized Cd-MOFs have also been discussed in this report.

N-doped porous carbons (NPCs) are characterized by well-developed porosity and N-doped active sites, which makes them suitable for CO2 capture. However, their application in practice is obstructed by the relatively low N-doped content and unsatisfactory adsorption capacity. Herein, we report the synthesis of NPCs through the rational design of the precursor NUT-21 (NUT means Nanjing Tech University) with a record-high N content (up to 46.16%, wt). The NUT-21 was fabricated by the polymerization of two simple monomers of 2,4,6-tris(bromomethyl)mesitylene and 3,5-diamino-1,2,4-triazole with an unusually high N content of 70.67% (wt). With the carbonization of NUT-21 at different temperatures (500, 600, and 700 °C, respectively), a series of NPCs possessing various porosity and N contents are produced, successfully. For the NPC generated at 600 °C, the N content can reach 7.41% (wt), the surface area is 2208 m2/g, the micropore volume is 0.791 cm3/g, and the CO2 capacity is up to 8.3 mmol/g at 273 K and 1 bar, which is much higher than those of benchmarks including 13X zeolite (4.1 mmol/g) and activated carbon (2.8 mmol/g), and most carbon-based adsorbents reported till now. It was proved in our previous studies that the ultrahigh N content of the precursor was beneficial for both the formation of developed porosity and the generation of abundant N-doped sites, which can give rise to superior capacity and selectivity of CO2 capture. The NPCs obtained may offer to be highly promising candidates for CO2 separation from gas mixtures including natural gas and flue gas.

The effect of hydraulic retention time (HRT) and pH on the biooxidation of ferrous iron during simulated acid mine drainage (AMD) treatment was investigated. The simulated AMD was highly acidic (pH 2.5), rich in iron (about 1700 mg/L) and copper (about 200 mg/L), and contained high concentrations of sulfate (about 4700 mg/L). The biooxidation of ferrous iron was studied in a laboratory-scale upflow packed bed bioreactor (PBR). The HRT was shortened stepwise from 40 h to 20 h, 13 h, and 8 h under the acidic environment at a pH value of 2.2. Then, the influent pH value was changed from 2.2 to 1.2 at a constant suitable HRT. Physiochemical and microbial community structure analyses were performed on water samples and stuffing collected from the bioreactor under different conditions. The results indicate that the efficiency of ferrous iron oxidation gradually decreased with the decrease of HRT, and when the HRT exceeded 13 h, ferrous iron in AMD was almost completely oxidized. In addition, the best efficiency of ferrous iron oxidation was achieved at the influent pH value of 1.8. Microbial community structure analyses show that Leptospirillum is the predominant genus attached in the bioreactor, and low influent pH values are suitable for the growth of Leptospirillum. Keywords: Acid mine drainage, Iron-oxidizing bacteria, Biooxidation of ferrous iron, Hydraulic retention time, Influent pH, Microbial community analyses

FeS2/Fe composites were mechanochemically prepared with iron powder and pyrite for the stabilization of ferrite arsenate sludge (FAS). The effects of preparation parameters on stabilization performance were investigated. The results show that the optimum conditions are FeS2/Fe molar ratio of 5:5, milling time of 2 h, ball-to-material mass ratio of 15:1 and milling with stainless steel ball. Then, the composites were characterized by XRD, SEM, FTIR, etc. The physicochemical properties of FeS2/Fe mixture change dramatically, which is responsible for its excellent performance. Finally, the stabilization process of FAS was optimized. When the FAS is mixed with composites at mass ratio of 4:1 and milled for 30 min, the As leaching concentration of FAS can be reduced from 639.15 to 4.74 mg/L with the stabilization ratio of 99.2%.

A sequence of Cr-modified CeZr2Ox catalysts were synthesized through the co-precipitation way and applied in selective catalytic reduction (SCR) of NOx with ammonia. The optimal catalyst (Cr1CeZr2Ox) exhibited the excellent NH3-SCR activity and high SO2 resistance. From the characterization results, Cr species in Cr1CeZr2Ox could suppress the formation of ZrO2 crystals, which could also contribute to stronger surface acidity and reducibility. Besides, more Ce3+ and surface adsorbed oxygen species were observed on Cr1CeZr2Ox catalyst. On the basis of in situ DRIFT experiments, it could be confirmed that the NH3-SCR process on Cr1CeZr2Ox was promoted through Langmuir-Hinshelwood (L-H) mechanism. Besides, the improved NO oxidation and more ad-NOx and ad-NH3 also played a vital role for the superior low-temperature SCR activity of Cr1CeZr2Ox.

In the rescue of hydrogen-fueled vehicle accidents, once accidental leakage occurs and hydrogen enters the cabin, the relatively closed environment of the vehicle is prone to hydrogen accumulation. Excessive hydrogen concentration inside the vehicle cabin may cause suffocation death of injured passengers and rescue crews, or explosion risk. Based on hydrogen fuel cell vehicle (HFCV) with hydrogen storage pressure 70 MPa, four different scenarios (i. with opened sunroof, ii. opened door windows, iii. opened sunroof and door windows and iv. opened sunroof, door windows and rear windshield) under the condition of accidental leakage were simulated using computational fluid dynamics (CFD) tools. The hydrogen concentration inside the vehicle and the distribution of flammable area (>4% hydrogen mole fraction) were analyzed, considering the effect of ambient wind. The results show that in the case of convection between interior and exterior of the vehicle via the sunroof, door windows or rear windshield, the distribution of hydrogen inside the vehicle is strongly affected by the ambient wind speed. In the least risk case, ambient wind can reduce the hydrogen mole fraction in the front of the vehicle to less than 4%, however the rear of the vehicle is always within flammable risk.

Because of their high stability, abundant porosity, and tailorable surface properties, N-doped porous carbons (NPCs) have played a crucial part in CO2 capture. Development of an efficient and low-cost method to fabricate NPCs remains a significant challenge. Herein, we report for the first time the preparation of NPCs through the rational design of the N-enriched polymer NUT-20-EDA (NUT, Nanjing Tech University; EDA, ethylenediamine) as the precursor. The NUT-20-EDA was obtained by polymerization of two simple monomers of mesitylene and formaldehyde dimethyl acetal, followed by post-synthetic ammonification. Through carbonization at temperatures ranging from 600 °C to 800 °C, NPCs with different porosity and N contents are fabricated, successfully. The reference porous carbons (rPCs) are also synthesized based on the polymer NUT-20 without post-synthetic ammonification. For the representative sample generated at 700 °C (NPC-700), the surface area is up to 1852 m2/g, which is much larger than its counterpart rPC-700 (1324 m2/g). Moreover, the CO2 uptake of NPC-700 (7.1 mmol/g at 0 °C and 1 bar) is higher than that of rPC-700 (5.9 mmol/g), and also superior to those of many benchmarks reported, including 13X zeolite (4.1 mmol/g) and activated carbon (2.8 mmol/g). Therefore, it is proved that, as a pore-foaming agent during the carbonization, the amino groups incorporated play a significant role in the formation of abundant porosity of the NPCs, which is one of the crucial factors for CO2 adsorption, and the N-species doped in NPCs can work as the CO2-philic sites to enhance the CO2 capture.

The effect of grain size and phase compositions on piezoelectric coefficient of BaTi0.98Hf0.02O3 ceramics prepared at a series of sintering temperatures (1320, 1350, 1370, and 1400 °C) was studied. The results showed that the grain size of the ceramics is 0.9, 21.3, 21.6, and 37.2 μm, respectively, and the corresponding phase compositions are the tetragonal–orthogonal, tetragonal–orthogonal–rhombohedral, tetragonal–orthogonal, and tetragonal–orthogonal–rhombohedral, while the piezoelectric coefficient is 475, 352, 258, and 327 pC/N, i.e., it decreases first and then increases as the grain size goes up. The phase compositions and grain size of the ceramics are interrelated, and they co-affect the piezoelectric coefficient.

Hydrogen is an ideal energy with little impact on the environment to tackle the intense energy crisis. Development of highly efficient electrocatalysts for low–cost hydrogen production from water splitting is vital for the real-world practical applications. Herein, a three dimensional hierarchical graphdiyne (GDY)@NiFe layered double hydroxide (LDH) heterostructured catalyst toward overall water splitting is developed by coupling NiFe LDH and GDY growth on copper foam (CF). The catalyst exhibits high electrocatalytic activities in both oxygen evolution reaction (OER) and hydrogen evolution reaction with overpotentials of 220 mV and 163 mV at a current density of 10 mA cm−2, respectively. The Tafel slope for OER is 39.33 mV dec−1, which is much lower than that of the only NiFe LDH/CF with a value of 112 mV dec−1. Thus, the GDY@NiFe LDH/CF heterostructure electrocatalyst leads to an improvement in the overall water splitting activity, with a current density of 20 mA cm−2 at the voltage of 1.512 V. Density functional theory calculation indicates that the synergetic effects of 3d orbit of transition metal atoms and carbon–carbon triple bonds in GDY are responsible for the bifunctional excellent electrocatalytic activity for overall water splitting.

Human papillomaviruses (HPVs), for instance, HPV 16 and HPV 18, are concerned associated with cervical cancer. Thus, it is essential to suppress HPVs-in HPV-positive cervical cancer for treating cervical cancer. The purpose of this study was to explore the proposed molecular mechanisms, which that underlies the antintumor potential of juglone to treat of HPV-positive on cervical cancer cells. The results showed that juglone suppressed HPV-positive cell growth in a dose- and time-dependent way. In addition, cell invasion and metastasis were also inhibited by juglone. Nevertheless, when pin 1 was knocked down in HPV-positive cells, cell proliferation, invasion and metastasis were reduced. This study was designed to acquire an understanding of the mechanism of invasion and metastasis in HPV-positive cells suppressed by juglone. It provides evidence of the advantageous use of juglone in the future. Keywords: Juglone, HPV-positive, Cervical cancer cells, Invasion, Metastasis

The modification of halloysite nanotubes (HNTs) as fillers is very effective at improving the performance of polymers. A novel modification of HNTs through grafting dodecylamine onto their surfaces was conducted here. Owing to the improvement in dispersibility of HNTs in polytetrafluoroethylene (PTFE), the mechanical properties and wear resistance (in particular) of the dodecylamine-modified HNT-filled PTFE composite were enhanced significantly.

Ethnopharmacological relevance Xiaoyaosan (XYS), a famous TCM prescription with a long history of clinical use for relieving a wide variety of depression symptoms, consists of Radix Bupleuri (Bupleurum chinense DC.), Radix Angelicae Sinensis (Angelica sinensis (Oliv.) Diels), Radix PaeoniaeAlba (Paeonia lactiflora Pall.), Rhizoma Atractylodis Macrocepha lae (Atractylodes macrocephala Koidz.), Poria (Poria cocos (Schw.)Wolf), Radix Glycyrrhizae (Glycyrrhiza uralensis Fisch.), Herba Menthae Haplocalycis (Mentha haplocalyx Briq.), and Rhizoma Zin-giberis Recens (Zingiber officinale Rosc.). Aim of the study We aimed to characterize the diversity and variation of two kinds metabolites of brain, i.e. aqueous and lipophilic metabolites, gaining comprehensive insights into the metabolic processes of depression-like behavior, and to reveal the mechanisms of antidepressant-like effects of XYS. Materials and methods We first established a CUMS (Chronic Unpredictable Mild Stress)-induced depression-like behavior model. We then extracted both aqueous and lipophilic metabolites of rat brains by a two-phase extraction method, which were subsequently characterized by two differential sequences of 1H nuclear magnetic resonance (NMR). Multivariate analysis including Principal Components Analysis (PCA) and Orthogonal Partial Least Squares-Discriminate Analysis (OPLS-DA) was applied. Results Metabolic profiling by PCA indicated that XYS significantly reversed the metabolic perturbation caused by CUMS. OPLS-DA showed a total of 15 metabolites including 6 lipophilic and 9 aqueous metabolites was screened as potential biomarkers involved in CUMS-induced depression-like behavior. On top of this, five pathways including (1) D -glutamine and D-glutamate metabolism, (2) valine, leucine and isoleucine biosynthesis, (3) alanine, aspartate and glutamate metabolism, (4) taurine and hypotaurine metabolism and (5) arginine and proline metabolism were recognized as the most influenced pathways associated with the process of CUMS-induced depression-like behavior. Notably, XYS significantly reversed abnormality of 5 aqueous and 4 lipophilic metabolites to normal, suggesting that XYS synergistically mediated abnormalities of multiple pathways (1), (3), (4) and (5). Conclusions It is the first report to investigate the antidepressant-like effects and underlying mechanisms of XYS from the perspective of brain metabolites. In a broad sense, this study brings novel and valuable insights to evaluate the efficacy of traditional Chinese medicine (TCM), to interpret mechanisms, and to provide the theoretical basis for further research on therapeutic mechanisms in clinical practice.

Rhodium(III)-catalyzed hydroarylation of terminal alkynes has not previously been achieved because of the inevitable oligomerization and other side reactions. Here, we report a novel Cp*Rh(III)-catalyzed hydroarylation of terminal alkynes in acetic acid as solvent to facilitate the C–H bond activation and subsequent transformations. This reaction proceeds under mild conditions, providing an effective approach to the synthesis of alkenylated heterocycles in high to excellent yields (31–99%) with a broad substrate scope (37 examples) and good functional-group compatibility. In this transformation, the loading of the alkyne can be reduced to 1.2 equivalents, which indicates the significant role of HOAc in lowering the reaction temperature and suppressing the oligomerization of the terminal alkyne. Preliminary mechanistic studies are also presented.

Deltamethrin is widely used because of its low toxicity and high efficiency. Although its potential toxicity has been reported, its effects on cardiovascular system and motor behavior and its underlying mechanisms have remained unclear. In this study, the effects of deltamethrin on the development, cardiovascular system and motor behavior of zebrafish larvae and their possible mechanisms were evaluated using the transgenic zebrafish Tg (kdrl:mCherry) and Tg(myl7:GFP). At 72 hpf, the body length of larvae shortened, the head and eye area decreased, and the hatching rate increased. Acridine orange staining showed that treated zebrafish larvae produced different degrees of apoptosis in the head, body, heart and tail regions. Quantitative fluorescence intensity showed a dose-dependent increase in apoptosis signal, indicating that deltamethrin could induce apoptosis. Confocal images and fluorescence intensity quantification of red fluorescent protein-labeled vascular endothelial cell and green fluorescent protein-labeled transgenic zebrafish more clearly reflected the dose-dependent cardiac and vascular morphology and the damage caused by deltamethrin. Deltamethrin significantly induced vascular endothelial growth factor flk1 and fli-1, cardiac development-related gene myl7 decreased in a dose-dependent manner. In addition, deltamethrin increased the thigmotaxis of zebrafish larvae, causing anxiety-like behavior. Our study showed that deltamethrin could cause developmental toxicity, apoptosis, cardiovascular system damage and anxiety-like behavior, which provided a reference for the use of deltamethrin in agricultural production.

AIMS As a natural antimicrobial agent, Melaleuca alternifolia oil (MAO) is generally recognized to be safe and effective in the inhibition of phytopathogenic fungi. Due to lack of comprehensive studies on MAO for controlling postharvest Aspergillus, we investigated the preservative mechanism of MAO and its components against Aspergillus ochraceus in postharvest grapes to evaluate their potential effectiveness as fruit preservatives. METHODS AND RESULTS In our study, the compositions in MAO were analysed by gas chromatography-mass spectrometry. The inhibitory effects of MAO and its main constituents against A. ochraceus were compared by scanning electron microscopy and transmission electron microscopy observation, and metabolic analysis. Two components of MAO, α-terpineol and terpene-4-alcohol, showed higher antifungal effects than MAO, of which α-terpineol caused the worst leakage of cytoplasm and most serious hyphae distortions and spore disruptions. The downregulation of metabolic pathways of A. ochraceus was strongest with α-terpineol. The best inhibitory efficacy against A. ochraceus in grapes also occurred with α-terpineol. 3-Carene showed little inhibitory effect. CONCLUSIONS These results demonstrate that not all components in MAO possess antimicrobial effects, and α-terpineol is the main contributor of MAO's A. ochraceus inhibition effect. SIGNIFICANCE AND IMPACT OF THE STUDY α-Terpineol may be used as an alternative natural preservative for the postharvest storage of grapes and other fruits.