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Anti-Aβ therapy has dominated clinical trials for the prevention and treatment of Alzheimer's disease (AD). However, suppressing Aβ aggregation and disintegrating mature fibrils simultaneously remains a great challenge. In this work, we developed a new strategy using a charged tubular supramolecule (CTS) with pillar[5]arene as the backbone and modifying amino and carboxyl groups at the tubular terminals (noted as CTS-A, CTS-A/C, and CTS-C, respectively) to suppress Aβ fibrillation for the first time. According to the spectroscopic and microscopic characterizations, Aβ40 fibrillation can be efficiently suppressed by CTS-A in a very low inhibitor:peptide (I:P) molar ratio (1:10). A greatly alleviated cytotoxic effect of Aβ peptides after the inhibition or disaggregation process is further disclosed. The well-organized supramolecular structure drives multivalent interaction and gains enhanced efficiency on amyloid fibrillar modulation. These results open a new path for the design of supramolecules in the application of AD treatment.

Electroreduction of CO2 into formate catalyzed by metal-organic frameworks (MOFs) is a promising avenue to promote the carbon cycle, but the oxygen evolution reaction (OER) process in anode usually limited the reaction efficiency. Here, a new framework {(Me2NH2)[Bi(L)]·4DMF·2H2O}n (V12) was constructed and structurally characterized (L = 5,5'-(1,3,6,8-tetraoxo-1,3,6,8-tetrahydrobenzo[lmn][3,8]phenanthroline-2,7-diyl) dibenzene-1,3-dicarboxylic acid; DMF = N,N-dimethylformamide). V12 possesses large one-dimensional channels with the size of 1.5 × 0.7 nm and exhibits good stability in common solvents. After V12 was modified on electrode via electrodeposition, as-synthesized sample exhibits impressive catalytic performance for the transformation of CO2 into formate with Faraday efficiency of 93.2% and current density of 11.78 mA cm−2 at −0.9 V (vs. RHE). Control experiments revealed that the MOFs electrodeposition strategy significantly improves the charge transfer rate and introduces more structural defects, which promotes the reaction activity. Moreover, tetrahydroisoquinoline is added as an accelerant in the anode to achieve the simultaneous generation of formate and dihydroisoquinoline. More importantly, the cell voltage is reduced from 2.79 to 2.52 V at 10 mA cm−2 in a two-electrode system due to more positive reaction kinetics. This work provides an enlightening strategy for using MOFs to establish an effective system to achieve CO2 reduction while obtaining high value-added oxidation products.

In rec ent years, Sb-based composites, as a kind of electrode alloy mechanism, have attracted more and more researchers’ attention owing to high theoretical specific capacity and reliable safety performance. However, the volume expansion of Sb-based electrode materials during charge/discharge in the process of (de)lithium leading to unstable cycling performance severely limits the progress of Sb-based electrode materials as electrode materials for commercialization. Therefore, we prepared N-doped 3D porous carbon to wrap Sb-Mo nanoparticles in a comprehensible way. By this method, the volume expansion problem of Sb-Mo nanoparticles during the (de)lithiation process can be effectively prevented, and the rate of capacity decay can be effectively mitigated. The obtained Sb-Mo@3DNC samples displayed superior electrochemical performance, especially that the Sb-Mo@3DNC700 exhibits more outstanding rate stability and long cycle performance than Sb-Mo@3DNC-600 and Sb-Mo@3DNC-800. It is worth that the Sb-Mo@3DNC-700 still possesses the reversible capacity of 352.5 mA h g−1 at the current density of 5 A g−1 and maintains the reversible capacity of 661.7 mA h g−1 after 1200 cycles at the current density of 1 A g−1.

This study uses a micro-electromechanical system (MEMS) structure to fabricate a cupric oxide (CuO) nanosheet (NS) gas sensor. A CuO-NS with a size ranging from 100 to 500 nm is produced by chemica...

Tanshinone IIa (TanIIa), an ingredient of Radix Salviae Miltiorrhizae, has an anticancer effect on various solid tumors with high efficiency and low toxicity. Nonetheless, the underlying role of TanIIa in acute promyelocytic leukemia (APL) remains unclear. Here, we revealed that TanIIa drastically inhibited NB4 cell viability with an IC50 value of 31.25 μmol/L. Using flow cytometry apoptosis assay, we identified that TanIIa dose-dependently exacerbated NB4 cell apoptosis. Mechanistically, TanIIa upregulated apoptotic factor levels, namely, cleaved-caspase 9, cleaved-caspase 3, and cleaved-PARP-1. Moreover, we noticed that TanIIa dose-dependently suppressed the PI3K/Akt/mTOR axis. This axis not only functions as an essential antiapoptotic modulator but also serves as a suppressant regulator of autophagy. Correspondingly, we detected the levels of autophagic marker, namely, LC3B, which were increased after the TanIIa treatment. Furthermore, the autophagy inhibitor Baf-A1 could effectively reverse the TanIIa-induced apoptosis, manifesting that TanIIa eliminated NB4 cells in an autophagy-dependent manner. In conclusion, tanshinone IIa exerts anti-APL effects through triggering autophagy and apoptosis in NB4 cells.

Background Tanning is an important physiological process that play the critical roles in affecting cuticle pigmentation and sclerotization. Previous studies have showed that insect cuticle tanning was closely associated with tyrosine metabolism pathway that consisted of a series of enzymes. Results In this study, a total of 24 tyrosine metabolism pathway genes were identified in the oriental fruit fly Bactrocera dorsalis (Hendel) genome. Then, the gene expression profiles throughout 15 developmental stages of B. dorsalis were established on the basis of our previous RNA-seq data, and we found 13 enzyme genes could be involved in the process of pupariation. Accordingly, a predicted tyrosine-mediated tanning pathway during the pupariation of B. dorsalis was obtained, and a critical enzyme 3,4-dihydroxyphenylalanine (DOPA) decarboxylase (DDC) was selected to explore its possible functions in the formation of puparium. Firstly, the RT-qPCR confirmed that BdDDC had epidermis-specific expression pattern, and it was also highly expressed during the larval metamorphosis of B. dorsalis. Subsequently, the dysfunction of BdDDC by feeding 5-day-old larvae with DDC inhibitor (L-α-Methyl-DOPA) could lead to (i) the significant decreasing of BdDDC enzyme activity and dopamine concentration; (ii) the defects in puparium pigmentation; (iii) the impairment of morphology and less thickness of puparium; (iv) the lower pupal weight and obstacle to eclosion. Conclusion The present study provided us a potential tyrosine metabolic pathway that was responsible for insect tanning during the pupariation, and the BdDDC enzyme has been proved to act the crucial roles in larval-pupal tanning of B. dorsalis. This article is protected by copyright. All rights reserved.

On the basis of the global warming effect, it is of great significance to convert CO2 into the high value-added products oxazolidinones, but investigations on main-group-based metal-organic frameworks (MOFs) as heterogeneous catalysts still have not been reported so far. In this work, a quadruple-interpenetrated porous indium-based MOF, {[NH2(CH3)2][In(CPT)2]·3CH3CN·3DMA}n (1), is constructed from the organic ligand 3,5-bis(4'-carboxyphenyl)-1,2,4-triazole through solvothermal reactions, and N2 adsorption proves that the framework has a high Brunauer-Emmett-Teller surface areas with 2024 m2/g. The catalytic research on CO2 conversion reveals that compound 1 has high reactivity for the cycloaddition of CO2 with aziridines, and the product 3-ethyl-5-phenyloxazolidin-2-one can be obtained with a yield of 99% under mild conditions. In addition, 1 exhibits excellent activity for different kinds of substrates and can be reused at least five cycles without any significant deactivation, suggesting that 1 is a potential candidate for the chemical conversion of CO2 and aziridines. Mechanistic explorations indicate that the high efficiency of 1 is attributed to the indium center in the framework as a Lewis acid site, and the large porosity can enrich substrates. Importantly, 1 behaved as the first main-group MOF-based catalyst in the reported coupling reaction of CO2 with aziridines.

Electrocatalytic reduction of carbon dioxide by metal-organic framework (MOF) catalysts has been widely investigated in recent years, but the poor conductivity strongly limits the application of most MOFs catalysts. In order to overcome the above obstacles, we tried to use a gentle strategy to uniformly introduce highly dispersed carbon nanoparticles into the framework to improve the catalytic activity. Herein, a porous 3D In-MOF {(Me2NH2)[In(BCP)]·2DMF}n (V11) with good stability was constructed, and there are two types of large 1D channels with a diameter of 1.6 and 1.2 nm in the framework. Experimental results show that V11 exhibits a moderate catalytic activity in CO2 electroreduction with 76.0% of Faradaic efficiency for formate. To improve the catalytic activity of V11, methylene blue molecules were introduced into the framework as a carbon source due to its suitable size and carbonization temperature. After calcination at an appropriate temperature, carbon nanoparticles (CPs) with an average diameter of 3.85 nm were anchored in V11 and the framework can keep stable during the synthesis process. The obtained catalyst CPs@V11 was also applied in the CO2 electroreduction, and the maximum Faradaic efficiency of formate increases from 76.0% to 90.1% and the current density increased by 2.2 times. Control experiments and catalytic characterizations demonstrate that the introduced carbon nanoparticles can serve as accelerant to promote the charges and mass transfer in framework, and benefit to sufficiently expose active sites. Furthermore, this strategy can also work on other In-MOFs to improve the catalytic performance in selectivity and current density, demonstrating the good universality of this facile method and giving inspiration to construct more effective catalysts for electroreduction of CO2.

Soil nematodes play a fundamental role in regulating ecosystem carbon and nutrient cycling. It is widely recognized that soil nematode community composition is sensitive to nutrient enrichment, but the linkage between community assembly processes and functional changes under nutrient enrichment condition remains poorly understood. We examined the compositional and functional responses and quantified the role of main community assembly processes (genus losses, genus gains, and context-dependent variations of abundance) in driving the carbon budget of soil nematode communities in response to nitrogen (N) and phosphorus (P) addition in a temperate grassland. Nitrogen and P addition significantly interacted to affect nematodes abundance, biomass, and functional variables of C cycling, in that P addition increased all the variables under ambient N condition but not under N enriched condition. Soil pH, ammonium concentration, and total phosphorus concentration played important roles in driving the variations of nematode C budgets, indicating the minor role of plant community characteristics. The enhancement of all variables following P addition was caused by the increases in the abundance of common genera (e.g. Acrobeles, Scutylenchus, and Tylencholaimus). The variation of genus richness contributed to the P-induced increases of nematode abundance but not to the increases of carbon budgets. Our results uncover the linkages between community assembly processes and the abundance and C cycling function of soil nematode community under nutrient enrichment conditions. The significant interactive effects between N and P addition highlight the complexity in predicting the compositional and functional changes in soil nematode community under a scenario of multiple-nutrient enrichment.

Calcium (Ca) is an essential nutrient for plant growth and Ca concentrations in forage have important implications for ruminant diet and health. It remains an open question whether forage Ca concentration would be decreased by increasing nitrogen (N) deposition. We manipulated the increasing rates of N addition (2008–2015) in a semiarid grassland, northern China. Plant Ca concentrations for all species were examined in each plot under N treatment. The Ca concentrations at functional group and community levels were calculated based on the concentration of each species presented and their relative biomass in each plot. We found that community-level Ca concentration remained stable across a gradient of wide-ranged N addition rates, although Ca concentration at both species and functional group levels showed negative responses to N enrichment. Given that forbs had higher Ca concentration than grasses, the increasing relative biomass of forbs canceled out the negative responses of species-level and functional group-level Ca concentration. Our results further showed that community Ca pool showed a positive but saturating response to N addition, with a threshold at the rate of 10 g N m−2 yr−1. Our findings highlight the role of changes in plant relative biomass in controlling the responses of forage Ca concentration and stock to N enrichment.

Cyclization of propargylamines with CO2 to obtain 2-oxazolidone heterocyclic compounds is an essential reaction in industry but it is usually catalyzed by noble-metal catalysts with organic bases as co-catalysts under harsh conditions. We have synthesized a unique CuI /CuII mixed valence copper-based framework {[(CuI6 I5 )Cu3II L6 (DMA)3 ](NO3 )⋅9DMA}n (1) with good solvent and thermal stability, as well as a high density of uncoordinated amino groups evenly distributed in the large nanoscopic channels. Catalytic experiments show that 1 can effectively catalyze the reaction of propargylamines with CO2 , and the yield can reach 99 %. The turnover frequency (TOF) reaches a record value of 230 h-1 , which is much higher than that of reported noble-metal catalysts. Importantly, this is the first report of heterogeneously catalyzed green conversion of propargylamines with CO2 without solvents and co-catalysts under low temperature and atmospheric pressure. A mechanistic study reveals that a triply synergistic catalytic effect between CuI /CuII and uncoordinated amino groups promotes highly efficient and green conversion of CO2 . Furthermore, 1 directly catalyzes this reaction with high efficiency when using simulated flue gas as a CO2 source.

Physicochemical and thermal characteristics of Moringa oleifera seed oil were studied. The refractive index of Moringa oleifera seed oil at ambient temperature was 1.46. The acid, peroxide, saponification, and iodine values content of Moringa oleifera seed oil were 2.35 g KOH/kg oil, 7.2 meq O2/kg oil, 189.84 g KOH/kg oil, and 66.78 g I2 /100 g oil, respectively. Moringa oleifera seed oil contains ten fatty acids. Among 10 kinds of fatty acids in Moringa oleifera seed oil, oleic acid is the most abundant fatty acid comprising 70.85% of total oil followed by palmitic acid (8.98%). The unsaturated fatty acids represented by oleic acid are mainly distributed in the Sn-2 position, which is as high as 95.59%. It contains a high level of unsaturated fatty acids. Moringa oleifera seed oil contains 233.29 mg/kg α-tocopherol, 9.04 mg/kg β-tocopherol, and 10.13 mg δ-tocopherol, respectively. Determination of 10 elements in Moringa oleifera seed oil by ICP-MS. Among them, calcium has the highest content. Moringa oleifera seed oil remained stable up to 305 °C with a negligible degradation. Moringa oleifera seed oil has high nutritional value and broad development prospect. This research provides a prospect for the comprehensive development and utilization of Moringa oleifera seed oil. The basic physical and chemical properties and structure of Moringa oleifera seed oil was analyzed and characterized

We developed a voltage-sensitive artificial transmembrane channel by mimicking the dipolar structure of natural alamethicin channel. The artificial channel featured a zwitterionic structure and could undergo voltage-driven flipping in the lipid bilayers. Importantly, this flipping of the channel could lead to their directional alignment in the bilayers and rectifying behavior for ion transport.

Cycloaddition of CO2 with aziridines is an important reaction to obtain high-value products. Porous MOFs can catalyze this reaction, but co-catalysts are still necessary to improve the catalytic performance. Such a reaction catalyzed by MOFs-based materials without co-catalyst has not been reported hitherto. Herein, a porous and stable three-dimensional (3D) framework {[Ni(DCTP)]·6.5DMF}n (1) with a large Langmuir surface area of 3,789 m2/g was synthesized, which displayed high I2 adsorption ability up to 731.0 mg/g and could release it reversibly. Additionally, it exhibited a high CO2 adsorption capacity of 104.0 cm3/g at 273 K. The investigation results revealed 1 could effectively catalyze the cycloaddition of CO2 and aziridines in the absence of additional co-catalyst, and it could maintain the catalytic activity after five cycles. Furthermore, 1 also exhibited high catalytic activity for the gram-scale experiment. Importantly, it is the first MOF material as a heterogeneous catalyst for the conversion of CO2 and aziridines without co-catalyst.

The occurrence of hypoxia-ischemia (HI) in the developing brain is closely associated with neuronal injury and even death. However, the underlying molecular mechanism is not fully understood. This study was designed to investigate phosphatase and tensin homolog (PTEN) nuclear translocation and its possible role in rat cortical neuronal damage following oxygen-glucose deprivation (OGD) in vitro. An in vitro OGD model was established using primary cortical neurons dissected from newborn Sprague-Dawley rats to mimic HI conditions. The PTENK13R mutant plasmid, which contains a lysine-to-arginine mutation at the lysine 13 residue, was constructed. The nuclei and cytoplasm of neurons were separated. Neuronal injury following OGD was evidenced by increased lactate dehydrogenase (LDH) release and apoptotic cell counts. In addition, PTEN expression was increased and the phosphorylation of extracellular signal-regulated kinase 1/2 (p-ERK1/2) and activation of nuclear factor kappa B (NF-κB) were decreased following OGD. PTENK13R transfection prevented PTEN nuclear translocation; attenuated the effect of OGD on nuclear p-ERK1/2 and NF-κB, apoptosis, and LDH release; and increased the expression of several anti-apoptotic proteins. We conclude that PTEN nuclear translocation plays an essential role in neuronal injury following OGD via modulation of the p-ERK1/2 and NF-κB pathways. Prevention of PTEN nuclear translocation might be a candidate strategy for preventing brain injury following HI.

Selective dephosphorylation is full of great challenges in the field of biomimetic catalysis. To mimic the active sites of protein phosphatase, Hf-OH-Hf motif-containing metal–organic frameworks (MOFs) were obtained and structurally characterized, which are assembled from [Hf48Ni6] cubic nanocages and exhibit good stability in various solvents and acid/base solutions. Catalytic investigations suggest as-synthesized Hf–Ni and Hf–Ni–NH2 display accurate type-selectivity (selectively catalyzed P–O rather than S–O or C–O bonds) and position-selectivity (selectively catalyzed phosphomonoesters over phosphodiesters) for the hydrolysis of phosphoesters. Reaction kinetic studies further revealed the high activity of the catalytic sites in these catalysts, and the unique catalytic selectivity and high activity are comparable to phosphatase. Additionally, these MOF catalysts possess good recursivity and hypotoxicity. Control experiments (including Hf- and Zr-based isomorphous MOFs) and theoretical calculations indicate that both triplet nickel and Hf6 clusters play significant roles in the unique binding site and favorable binding energy. To our knowledge, this is the first example of selective dephosphorylation through MOF catalysts as mimic enzymes, which paves a potential way for the development of specific therapeutic MOFs., Metal−organic frameworks assembled by [Hf48Ni6] cubic nanocages consisting of Hf6 clusters and porphyrin-like ligand units have been shown for the first time to have accurate catalytic dual-selectivity in dephosphorylation mimicking phosphatase. The activity and selectivity were further elucidated by control experiments and theoretical calculations with calculated binding energies as well as structure details through density functional theory methods.

Achieving high capacitance at high current density is one of the challenges for battery electrode materials to practical applications, especially for metal oxide electrode materials. Herein, we designed a unique corn-like architecture composed of Se-doped carbon load Fe3O4 particles (C/Se-L-Fe3O4) through a strategy of simple displacement reaction. In this corn-like structure, the selenium-doped rod-shaped carbon provides a fast electron transport network, and the Fe3O4 nanoparticles anchored on the surface of Se-doped carbon rod, which can have direct contact with the electrolyte, thus greatly shortening the ion transmission path. Benefiting from these advantages, C/Se-L-Fe3O4 electrodes exhibit good stability and an ultrahigh specific capacity of 942.2 mAh g−1 after 600 cycles at 1 A g−1. Especially, under a high current density of 5 A g−1, a specific capacity of ca. 443 mAh g−1 is still retained, which is much higher than that of reported carbon-coated metal oxide electrode materials, confirming its excellent rate capability. The optimized structure and facile fabrication method provide a promising way for the utilization of transition metal oxides as high-performance and long life energy storage materials.

Due to the widespread use of dinotefuran around the world, its impact on food and environmental safety has aroused great concern, and the establishment of a rapid and convenient approach for dinotefuran detection is necessary but challenging. Herein, we synthesized a unique three-dimensional framework {[(CH3)2NH2]2[Cd3(BCP)2]·10H2O·3.5DMF}n (1). Single-crystal X-ray analysis indicates that 1 possesses a 4,8-connected anion framework that corresponds to alb topology, with a one-dimensional rectangular channel along the c-axis with the size of 4 A × 10 A. Compound 1 displays satisfactory solvent and thermal stability. Luminescent investigations reveal that 1 can selectively detect dinotefuran by fluorescence quenching among other pesticides, displaying excellent anti-interference performance with common ions in water. Importantly, the limit of detection is as low as 2.09 ppm, which is far below the residual concentration of the U.S. food standard. A fluorescence quenching mechanism study shows that there exists competitive energy absorption and static quenching processes. To our knowledge, 1 is the first MOF-based fluorescence probe for dinotefuran detection.

In view of the current situation of high cost and low catalytic efficiency of the commercial Pd-based catalysts, adding transition metals (Ni, Co, etc.) to form the Pd-M bimetallic catalyst not only reduces the consumption of Pd but also greatly improves the catalytic activity and stability, which has attracted increasing attention. In this work, the three-dimensional network Pd-Ni bimetallic catalysts were prepared successfully by a liquid-phase in situ reduction method with the hydroxylated γ-Al2O3 as the support. Through investigating the effects of the precursor salt amount, reducing agent concentration, stabilizer concentration, and reducing stirring time on the synthesis of the Pd-Ni nanocatalyst, the three-dimensional network Pd-Ni bimetallic nanostructures with four different atomic ratios were prepared under an optimal condition. The obtained wire-like Pd-Ni catalysts have a uniform diameter size of about 5 nm and length up to several microns. After closely combining with the hydroxylated γ-Al2O3, the supported Pd-Ni/γ-Al2O3 catalysts exhibit nearly 100% conversion rate and selectivity for the hydrogenation of nitrobenzene to aniline at low temperature and normal pressure. The stability testing of the supported Pd-Ni/γ-Al2O3 catalysts shows that the conversion rate still remained above 99% after 10 cycles. There is no doubt that the supported catalysts show significant catalytic efficiency and recyclability, which provides important theoretical basis and technical support for the preparation of low-cost, highly efficient catalysts for the hydrogenation of nitrobenzene to aniline.

Hydrogen sulfide (H2S) content has been shown to be significantly increased in colon cancer tissue; imaging H2S in vivo enables the accurate diagnosis of colon cancer disease. Photoacoustic (PA) im...

A series of peptide-appended bisresorcinarenes were synthesized, which adopted tubular conformation induced by intramolecular hydrogen bonds. The derivatives formed unimolecular artificial transmembrane channels in lipid bilayers to enable selective transport of monovalent cations. Importantly, the channels exhibited reversible ligand-gating behavior in response to alkyl amine and Cu2+.

Transition metal selenides have become the focus of research in recent years, owing to their large specific capacity and fast charging/discharging speed. However, the rapid decay of the specific capacity resulting from the large volume change that occurs during cycling and the damage caused to the electrode structure, seriously impedes their practical applications. In this work, Cd-doped Fe3C nanoparticles embedded in nitrogen-containing carbon (Fe3C–Cdn/C–N) precursors were first prepared using a simple sol–gel method, and then FeSe doped with Cd loaded on nitrogen-containing carbon (FeSe–Cdn/C–N) composites were obtained using a selenization process. These composites exhibited a high conductivity and special structural durability, thus ensuring good charge transport kinetics. As expected, the FeSe–Cdn/C–N electrode displayed a high specific capacity, excellent rate performance and ultra-stable long-term cycling stability. It delivered a reversible capacity of 745 mA h g−1 for 550 cycles at a rate of 2.0C, much higher than that of the non-Cd doped FeSe/C–N (288 mA h g−1). More impressively, it maintained a capacity of 438.8 mA h g−1 at 5.0C during the rate capability testing, exhibiting an excellent rate performance. The results demonstrate that iron-based selenides have good prospects for further development and that cadmium doping can significantly improve the electrochemical performance of lithium ion batteries.

A series of glycoside-peptide conjugates were prepared by engineering at the N-terminus of the natural peptide gramicidin A. The conjugate containing galactose moiety formed a unimolecular transmembrane channel and mediated ion transport to induce apoptosis of cancer cells. More importantly, it exhibited liver cancer cell-targeting behavior due to the galactose-asialoglycoprotein receptor recognition.

Nowadays with the increasing demand for lithium-ion batteries (LIBs), the high-capacity silicon anode is becoming a promising electrode material. However, the huge expansion of silicon during long cycling remains a significant challenge. Herein, a functional double layer Si-based multi-component structure Si@void C@TiO2 was designed as anode material for lithium-ion batteries. This structure has a void space inside and a double shell composed of carbon layer and crystalline TiO2 outside, which not only takes effective in improving electric conductivity of the Si electrode material, but also maintains the structural stability and integrity of the electrode. The layers impede the electrolyte from contacting with Si, contributing to forming a stable SEI film and providing high Coulombic efficiency. Therefore, the Si@void C@TiO2 electrode provides a high reversible capacity of 1251 mA h g-1, and stable long cycling with a capacity of 668 mA h g-1 over 500 cycles at a current density of 100 mA g-1, and 98% average Coulombic efficiency, making this potential superior material Si-based multi-component anode a high-performance electrode material for Li-ion batteries.

In this paper, starch, distarch phosphate (DSP) and hydroxypropyl distarch phosphate (HPDSP) were used as “green” carbon sources with ammonium polyphosphate (APP) to prepare flame retardant reconstituted tobacco sheet (RTS) by paper-making process and the effect of these starch-based flame retardants on their thermal degradation and combustion properties was preliminarily investigated. Micro-scale combustion calorimetry results showed the value of the heat release of modified RTS was lower than that of pure RTS, demonstrating the restrained combustion behavior of modified RTS. TG-FTIR and TG-MS analysis indicated that the starch-based flame retardant coating promoted the char formation, inhibited char combustion and release of gaseous products except for NH3, with the relative best comprehensive performance of APP-DSP. Cigarette burning cone analysis also confirmed that the modified RTS had lower temperature and smaller burning cone volume than that of pure RTS, especially APP-HPDSP-RTS. This work could highly expand the application of starch and its derivatives in flame retardant and tobacco industry.

Non-additive effects during the decomposition of mixed litter at species level have important consequences on ecosystem nutrient cycling, whereas such effect at plant organ level remains unclear. We investigated mass loss and nutrient release of single and mixed litter from leaf and culm for a dominant grass and of shoots for two dominant grasses under both ambient and enriched N conditions in a temperate grassland. We found comparable mixing effects on litter mass loss and nutrient release at organ and species levels after 2-yr decomposition. Nitrogen enrichment stimulated litter mass loss of all litter types but did not alter the mixing effects on mass loss. Further, N enrichment enhanced the non-additive effects of mixing on N release at plant organ level but not at species level. This study extend the non-additive effects of litter decomposition from inter-specific level to intra-specific level by highlighting the synergistic interaction between leaf litter and culm litter during decomposition. Given the existence of non-additive mixing effects at plant organ level, it is more difficult to predict litter decomposition and nutrient cycling in herbaceous communities.

Controlling the morphology and pore size is the key to improving the efficiency of electrode materials. In this work, ZnO-CuOx/C, as a lithium-ion anode material, is prepared using ZIF-8@CuO as an initial composite material. The two metal oxides become uniformly distributed on the carbon material, which not only inherits the excellent pore structure and high specific surface area of ZIF-8 but also exhibits excellent conductivity and abundant active sites. Furthermore, ZnO-CuOx/C demonstrates outstanding lithium storage performance. After 500 cycles at a current density of 100 mA g−1, the capacity remains at a relatively high level of 1061.2 mAh g−1. After 1000 cycles at a current density of 1000 mA g−1, the capacity stays as high as 500 mAh g−1. Therefore, the prepared composite material possesses favourable rate capacity.

Cuticular proteins (CPs) are critical components of the insect cuticle and play important roles in maintaining normal insect development and defense against various environmental stresses. The oriental fruit fly (Bactrocera dorsalis) is one of the most destructive pests worldwide, and its eight CPs analogous to peritrophin 3 (BdCPAP3) family genes have been identified in our previous study. In the present study, we further explored the possible roles of CPAP3 genes in B. dorsalis development. Each sequence of BdCPAP3 genes contained three conserved ChtBD2 (chitin-binding) domains. Spatial and temporal expression patterns revealed that the four BdCPAP3 genes (BdCPAP3-A1, B, E, and E2) might play important roles in larval pupariation of B. dorsalis. Moreover, treatment with a juvenile hormone analog (methoprene) significantly restricted expression of these four CPAP3 genes, whereas treatment with 20-hydroxy-ecdysone induced expression. The RNA interference (RNAi) results revealed that down-regulated CPAP3 genes led to significant delay of pupariation, and injection of dsBdCPAP3-E into 5-d-old B. dorsalis larvae caused approximately 40% mortality. Interestingly, we also confirmed that BdCPAP3-D2 was involved in B. dorsalis ovarian development. This study showed that some specific CPAP3 genes had crucial roles in B. dorsalis development, and these CP genes could be used as potential targets to control this pest via RNAi.

The continuing nitrogen (N) deposition observed worldwide alters ecosystem nutrient cycling and ecosystem functioning. Litter decomposition is a key process contributing to these changes, but the numerous mechanisms for altered decomposition remain poorly identified. We assessed these different mechanisms with a decomposition experiment using litter from four abundant species (Achnatherum sibiricum, Agropyron cristatum, Leymus chinensis and Stipa grandis) and litter mixtures representing treatment-specific community composition in a semi-arid grassland under long-term simulation of six different rates of N deposition. Decomposition increased consistently with increasing rates of N addition in all litter types. Higher soil manganese (Mn) availability, which apparently was a consequence of N addition-induced lower soil pH, was the most important factor for faster decomposition. Soil C : N ratios were lower with N addition that subsequently led to markedly higher bacterial to fungal ratios, which also stimulated litter decomposition. Several factors contributed jointly to higher rates of litter decomposition in response to N deposition. Shifts in plant species composition and litter quality played a minor role compared to N-driven reductions in soil pH and C : N, which increased soil Mn availability and altered microbial community structure. The soil-driven effect on decomposition reported here may have long-lasting impacts on nutrient cycling, soil organic matter dynamics and ecosystem functioning.

Artificial aquaporins are synthetic molecules that mimic the structure and function of natural aquaporins (AQPs) in cell membranes. The development of artificial aquaporins would provide an alternative strategy for treatment of AQP-related diseases. In this report, an artificial aquaporin has been constructed from an amino-terminated tubular molecule, which operates in a unimolecular mechanism. The artificial channel can work in cell membranes with high water permeability and selectivity rivaling those of AQPs. Importantly, the channel can restore wound healing of the cells that contain function-lost AQPs.

Nutrient addition is a widely-used strategy to restore degraded grasslands. It remains unknown whether and how the number of added nutrients affects the soil nematode community in degraded grasslands. We examined the immediate responses of taxonomic and functional composition of the soil nematode community to different numbers of added nutrients using factorial combinations of nitrogen (N), phosphorus (P), and potassium (K + micronutrients) in a degraded grassland of northern China. The taxonomic and functional composition of the soil nematode community generally formed a unimodal relationship with the number of added nutrients. Changes of soil pH after fertilization affected the structural stability and complexity of the soil nematode community. The magnitude of nematode functional responses to nutrient supply was driven by changes of plant aboveground biomass and soil pH. Soil nematode community showed non-linear responses to the variations of the number of added nutrients in a degraded grassland, which contrasts previous findings from plant community. The number of added nutrients should be given full consideration in formulating effective restoration strategies for degraded grasslands.

Background: Burning temperature is one of the most important factors affecting the chemical structure of the smoke and the addition of reconstituted tobacco sheet to cut tobacco has been widely used by the tobacco industry to reduce the cost of cigarettes and the health risks of smoking. Methods: A flame retardant film, made from chitosan and ammonium polyphosphate, has been coated on the surface of the reconstituted tobacco sheet substrate by Layer-by-Layer and spray coating techniques. The thermal degradation properties and flame retardancy of these reconstituted tobacco sheets were analyzed by TG-FTIR and micro-scale combustion calorimetry. Results: It was found that the reconstituted tobacco sheet with the ratio of chitosan (5%) and ammonium polyphosphate (3%) film coating showed significant reductions in the peak heat release rate (50.7%), total heat release (35.8%) and the highest temperature in the temperature distribution diagram (77°C). The main gases released during the pyrolysis of these reconstituted tobacco sheet samples were H2O, CO2, CO, NH3, carbonyl compounds and the presence of film coating changed the formation of evolved volatile products and formed less gaseous products except NH3 during the thermal decomposition process. Conclusion: The coating film can greatly enhance the char forming ability and reduce the flammability of reconstituted tobacco sheet, and therefore, reduce the health risks of smoking with the addition of these reconstituted tobacco sheets.

Anthropogenic nitrogen (N) deposition has affected plant community composition and nutrient cycling in terrestrial ecosystems worldwide. This includes changes to the way plants use and recycle nutrients, including effects on nutrient resorption, which is a key process through which plants recover nutrients from tissue during senescence. Nutrient resorption has considerable adaptive and functional significance for plants and helps regulate core ecosystem processes such as decomposition. However, our understanding of how N deposition affects nutrient resorption and, in particular, of how N inputs alter ecosystem resorption via changes to existing species’ resorption compared with changes to community composition remains poor. To disentangle the role of species versus community composition controls driving variation in nutrient resorption responses to N inputs, we carried out an experiment with six different N addition rates in a temperate steppe. We found that species-scale nutrient resorption responses to N enrichment were variable; for example, only half of the measured species reduced both N and P resorption efficiency in response to increased N inputs. In contrast, community-scale responses consistently resulted in reduced N and P resorption. Still, N-induced changes in community composition were a weaker control on overall resorption responses than were the effects on individual species; however, it was the synergistic interaction between the two that resulted in the large total reductions of nutrient resorption in the face of increased N. Taken together, our results highlight that understanding and predicting nutrient resorption responses will be most accurately scaled by accounting not only for species’ reductions in resorption but also for changes in community composition.

Highly stereoselective hydrogenation of α-pinene under mild conditions in the utilization of natural products is important but challenging. Here, we report a facile strategy for the size-controlled...

Uncovering the importance of soil and plant characteristics in driving the legacy effects of nitrogen (N) deposition on plant community nutrient stoichiometry would improve our understanding of plant-soil interaction during restoration of historically N-enriched ecosystems. Based on a field experiment with the cessation of six-year N addition in a temperate steppe of northern China, we measured concentrations and stoichiometry of N and phosphorus (P) in soils and different plant functional groups, under both mown and unmown conditions. Historical N addition did not affect soil total and available N and P concentrations and stoichiometry, but significantly altered plant community composition. Plant nutrient concentrations and N:P ratios significantly differed among four plant functional groups. The concentrations and stoichiometric ratios of N and P between soils and plants were generally not correlated. The positive legacy effects of N addition on community N:P stoichiometry were caused by the biomass enhancement of tall bunchgrass, the functional group with the highest N:P ratios. Changes in plant community composition instead of soil nutrient status were the main driver for the positive legacy effects of N enrichment on plant community stoichiometry. Given that the recovery of community composition after the cessation of N deposition is generally slow, our findings indicate that the legacy effects of N deposition on soil nutrient cycling would persist in long-term due to the importance of plant-mediated pathway.

Among a variety of traditional Chinese medicines, Shuanghuanglian injection (SHLI), has the highest incidence of injection-induced immediate hypersensitivity reactions (IHRs). However, the precise mechanisms of SHLI-induced IHRs remain to be understood. In the present study, we characteriszed IHRs as induced by SHLI by recording changes in physiological and hemodynamic indicators following intravenous injections of SHLI in rats and dogs. The results indicate that SHLI induced the release of histamine, decreased mean arterial blood pressure (MAP), increased SC5b-9 in rats and dogs, increased C4d and Bb in dogs without any changes in IgE. n vitro incubation of SHLI with serum from dogs in the presence of an inhibitor of complement activation (EGTA/Mg2+) resulted in an increase in C4d. These results suggest that SHLI induces anaphylactoid reactions in rats and dogs. Furthermore, SHLI appears to activate the complement system through classical and alternative pathways in dogs in vivo. Additional experiments in mice demonstrated that SHLI induces locus coeruleus infiltration and results in significant increase in vascular permeability within the skin of mice. We established a reliable method for the evaluation of anaphylactoid reactions induced by complex compounds, using multiple physiological indicators, different experimental models in vivo and in vitro.

The utilization of manganese oxide anode materials in lithium-ion batteries is hindered by low conductivity, high stress/strain, volume expansion, and high over potential in the crystalline structure during cycling. Compared with crystal oxide, amorphous oxide has attracted attention for its weak chemical bond force and its low stress change during the phase change process, but few reported in lithium-ion batteries. This work combined both advantages of amorphous manganese oxide (AMO) and reduced graphene oxide (rGo) to produce a unique AMO/rGo composite electrode material through one-step chemical reduction the KMnO4 in graphene oxide containing solution. The rGo-supported porous amorphous structure of manganese oxide brought special character by reducing the stress/strain of the conversion reaction, thus ensuring a high capacity and high stability. The high electronic and lithium-ion conductivity of graphene also enhanced the rate capability. As a result, the as-synthesized AMO/rGo exhibited a large reversible specific capacity (784 mA hg−1 at the current density of 1 A g−1 over 500 cycles) and superior rate capability, making it a potential candidate as high-performance electrode material for long-term cycling in lithium-ion batteries.

The stoichiometric traits of litter play an important role in driving litter decomposition and ecosystem nutrient cycling. While the impacts of nitrogen (N) deposition on the species-level litter stoichiometric traits have been well addressed, we know little about that at community-level, which is supposed to be driven by both intra-specific variation and changes in community composition. We examined the effects of N deposition on litter phosphorus (P) concentration and N:P ratio at both species- and community-level in a semi-arid grassland of northern China. We further decomposed the community-level variations of litter nutritional traits into intra- and inter-specific variation. Nitrogen addition, especially at high rates, substantially changed community composition. Litter P concentrations and N:P ratios significantly varied among different species. Litter P concentrations and N:P ratios at both species- and community-level were positively correlated with N addition rates. Biomass-weighted community-level N:P ratios were more sensitive to N addition than the non-weighted ones, indicating that community composition strengthened the positive impacts of N addition on litter N:P ratios. There was positive co-variation between intra- and inter-specific variation for litter N:P ratio, indicating the consistency of community composition and intra-specific variation in their effects on litter N:P ratio. Our results indicated that the imbalance of N and P following N enrichment would be much larger than the expectation based on the findings from species-level, and thus highlight the importance of changes in community composition in driving the responses of community-level litter N:P stoichiometry to N deposition in the semi-arid grassland.

High-valent transition metal or main group complex mediated σ-bond metathesis plays an important role in the activation of covalent H–E bonds. However, its involvement in the activation of C–C bond...

Objective: To investigate the anti-angiogenic effect of tea polyphenols (TPS) on breast cancer and normal tissues in a mouse model. Methods: Breast cancer was successfully implanted into 48 BALB/c mice, which were then randomly divided into a TP oral gavage group, a TP local injection group, a ginsenoside Rg3 group, and a model control group according to a random number table. The tumor inhibitory rates of each group were calculated, while microvessel density (MVD) and the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and tissue inhibitor of metalloproteinase (TIMP-2) were detected by immunohistochemistry. Results: TPs could inhibit the growth of breast cancer xenografts in the mouse model. The tumor inhibition rates of the TP oral gavage and TP local injection groups were 37.43% and 40.94%, respectively. Compared with the model control group, MVD and VEGF and bFGF expression was downregulated (all P