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The transmission of mobile wound signals along the phloem pathway is essential to the activation of wound-induced systemic response/resistance, which requires an upsurge of jasmonic acid (JA) in the distal undamaged leaves. Among these mobile signals, the electrical signal mediated by the glutamate-dependent activation of several clade three GLUTAMATE RECEPTOR-LIKE (GLR3) proteins is involved in the stimulation of JA production in distal leaves. However, whether JA acts as a mobile wound signal and, if so, how it is transmitted and interacts with the electrical signal remain unclear. Here, we show that JA was translocated from the local to distal leaves in Arabidopsis, and this process was predominantly regulated by two phloem-expressed and plasma membrane-localized jasmonate transporters, AtJAT3 and AtJAT4. In addition to the cooperation between AtJAT3/4 and GLR3.3 in the regulation of long-distance JA translocation, our findings indicate that importer-mediated cell–cell JA transport is important for driving the loading and translocation of JA in the phloem pathway in a self-propagating manner.

Simultaneously achieving high gravimetric capacitance and volumetric capacitance remains as a major challenge in the development of supercapacitor electrode materials. A class of hollow carbon nano bowls (HCNBs) with a unique semi-concave geometry has been synthesized by a facile template method. The HCNBs can serve as a nanoreactor for the in-situ space-confined growth of ultra-small size, few layer two-dimensional (2D) molybdenum disulfide (MoS2) nanosheets. When used as the electrode materials for supercapacitors, the MoS2 nanosheets inside HCNBs named MoS2@HCNBs demonstrated outstanding gravimetric capacitance (560 F g−1 at 0.2 A g−1) and volumetric capacitance (874 F cm−3) at the same time. The cycling performance of MoS2@HCNBs (94.4% capacitance retention after 5000 cycles) is also much higher than HCNB@MoS2 in which the surfaces of HCNBs were covered by the 2D MoS2 nanosheets. Several factors have been leading to the boosted performances and the mechanisms have been analyzed. The HCNBs with high surface area, developed porosity and ultrathin carbon shells promote the rapid electrolyte penetration and provide a conductive pathway for excellent ion and electron transport. The ultra-small few layer MoS2 nanosheets inside the HCNBs help to induce extra electrochemical double-layer capacitance as well as higher pseudocapacitance. More importantly, the semi-concave HCNBs can protect the structural stability of MoS2 nanosheets and contribute an enhanced packing density to further improve the volumetric capacitance of the hybrid MoS2@HCNBs.

The sulfur–iodine (SI) cycle is deemed to be one of the most promising alternative methods for large-scale hydrogen production by water splitting, free of CO2 emissions. Decomposition of hydrogen iodide is a pivotal reaction that produces hydrogen. The homogeneous conversion of hydrogen iodide is only 2.2% even at 773 K [1]. A suitable catalyst should be selected to reduce the decomposition temperature of HI and attain reaction yields approaching to the thermodynamic equilibrium conversion. However, residual H2SO4 could not be avoided in the SI cycle because of incomplete purification. The H2SO4 present in the HI feeding stream may lead to the poisoning of HI decomposition catalysts. In this study, the activity and sulfur poisoning of Ru and Ni catalysts loaded on carbon and alumina, respectively, were investigated at 773 K. HI conversion efficiency markedly decreased from 21% to 10% with H2SO4 (3000 ppm) present, which was reversible when H2SO4 was withdrawn in the case of Ru/C. In the case of Ru/C and Ni/Al2O3, catalyst deactivation depends on the concentration of H2SO4; the higher the concentration of H2SO4, the greater the severity of deactivation. Catalysts before and after sulfur poisoning were characterized by transmission electron microscopy (TEM), energy-dispersive X-Ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Experimental results and characterization of poisoned and fresh catalysts indicate that the catalyst deactivation could be ascribed to the competitive adsorption of sulfur species and change in its surface properties.

An integrated immobilization to encapsulate the Pd/C-coated magnetic nanoparticles within the chiral Ru/diamine-functionalized silica shell for the construction of a bifunctional magnetic catalyst is developed. This catalyst realizes a synergistic Suzuki cross-coupling/asymmetric transfer hydrogenation and a successive reduction/asymmetric transfer hydrogenation for the preparation of chiral aromatic alcohols.

The effects of three polysaccharides on the textural properties and microstructure of myofibrillar protein (MP) gels were studied. The gel strength and rheological properties of composite MP gels were significantly improved with insoluble dietary fibre (DF) and modified starch (MS) addition, while konjac glucomannan (KG) had limited effects at 1% addition. The SEM images indicated that moisture extrusion formed moisture channels and deteriorated the aggregation of MP gel networks during the thermal process. The polysaccharides stabilized moisture and reduced the appearance of moisture channels in the gel network, thereby promoting the formation of compact and integral gel networks. The MP-polysaccharide mixture is a thermally incompatible system and presented two main forms after the thermal process: 1) the “trapped” structure and 2) the “interpenetrated” structure. In the “trapped” structure, the MP was the dominant structure of the composite gel network. In the “interpenetrated” structure, the continuous polysaccharide hydrogel substantially hindered the aggregation of MP gel networks. Principal component analysis showed that the phase behaviour and moisture stability of polysaccharides significantly influenced the textural quality and microstructure of composite MP gelation. The study indicated that polysaccharides that contribute to moisture stability and form a “trapped structure” (phase behaviour) are ideal fat replacements for improving composite gel properties, especially DF.

Sulfur-iodine thermochemical water splitting cycle is a promising and carbon dioxide-free method for hydrogen production. Among the reactions in this cycle, hydrogen iodide catalytic decomposition is the rate-determining step. In this study, catalytic reactivity test combined with characterizations of nitrogen physisorption, X-Ray diffraction, and Raman spectroscopy provide evidences that hydrofluoric acid modified semi-coke is a promising catalyst candidate for hydrogen iodide decomposition because of its high active and low cost. The raw semi-coke enhanced the hydrogen iodide conversion rate. After modification of hydrofluoric acid, the catalytic activity of semi-coke increased largely. Semi-coke modified by 40 wt% hydrofluoric acid showed better performance than commercial activated carbon catalyst. Combine the characterization results and catalytic reactivity, the graphitic edge carbon atoms in semi-coke are the active sites for hydrogen iodide decomposition. This finding pointed out the direction of carbon material catalyst design for hydrogen iodide decomposition.

Impacts of coordinated water of nickel chloride hexahydrate (NiCl2·6H2O) on the properties of choline–urea (ChCl–2Urea) ionic liquid (IL), including viscosity and electrical conductivity, and electrodeposition behavior of Ni coatings were investigated. Results reveal that the coordinated water exhibited a profound influence on reducing viscosity, improved electrical conductivity and promoted the formation of a nanocrystalline Ni coating, while the Ni nucleation mechanism was not altered by the presence of coordinated water, proceeding via that from the progressive three-dimensional nucleation to instantaneous nucleation with hemispherical diffusion-controlled growth when the deposition potential shifts to the negative direction. When water content was maintained no more than ~ 8 wt%, a compact nanocrystalline Ni coating, with a current efficiency of almost 100%, was prepared from ChCl–2Urea–NiCl2·6H2O with an aid of 400 mg/L nicotinic acid (NA) at 318 K. These results indicate hydrated Ni salts can be used to replace anhydrous counterparts in preparation of Ni coating from choline–urea IL, which could reduce the impact on environment and product cost. Such a strategy may be extended to other hydrated metal salts in IL electrolyte electrodeposition for high-quality coating preparation.

Polyvinyl alcohol (PVA)/sodium alginate (SA) solution was electrospun to form fiber membranes. PVA/SA fiber membranes were characterized by Fourier Transform Infrared (FTIR), Energy Dispersive Spectrometer (EDX), X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC) and Thermal Gravimetric analysis (TGA). The hydrogen-bonding interaction between PVA and SA were demonstrated by FTIR, XRD, DSC. The preparation of fibers during electrospinning process involved various parameters such as SA content, electric voltage, receiving distance and the nozzle velocity that were optimized via Box-Behnken design (BBD) method. The findings revealed that the SA content had a major effect on the diameter of the fibers made, achieving a minimum fiber diameter of 242.12 nm under optimum production conditions. The effect of various PVA/SA contents on diameter, morphology, mechanical property, and liquid absorption property of the membranes were studied via scanning electron microscope (SEM) analysis, mechanical measurement and contact angle testing. The optimal physical properties of PVA/SA fiber membrane at 7:3 proportion were verified, which was close to the Response Surface Methodology (RSM) result.

To control gene expression by directly responding to hormone concentrations, both animal and plant cells have exploited comparable mechanisms to sense small-molecule hormones in nucleus. Whether nuclear entry of these hormones is actively transported or passively diffused, as conventionally postulated, through the nuclear pore complex, remains enigmatic. Here, we identified and characterized a jasmonate transporter in Arabidopsis thaliana, AtJAT1/AtABCG16, which exhibits an unexpected dual localization at the nuclear envelope and plasma membrane. We show that AtJAT1/AtABCG16 controls the cytoplasmic and nuclear partition of jasmonate phytohormones by mediating both cellular efflux of jasmonic acid (JA) and nuclear influx of jasmonoyl-isoleucine (JA-Ile), and is essential for maintaining a critical nuclear JA-Ile concentration to activate JA signaling. These results illustrate that transporter-mediated nuclear entry of small hormone molecules is a new mechanism to regulate nuclear hormone signaling. Our findings provide an avenue to develop pharmaceutical agents targeting the nuclear entry of small molecules.

Desalination of seawater using solar energy is a promising solution to the global freshwater shortage. Ultrahigh surface area (up to 1740 m2 g−1) hierarchical porous carbons (HPC) have been prepared by the carbonization of precursors derived from the room temperature dehalogenation of low cost, widely available polyvinyl chloride (PVC) with simple, low cost, environmentally friendly processes. The broad hierarchical pores (from 2 nm to 20 μm) facilitate and ensure fast water and vapor transportation. Flexible photothermal steam generation devices were successfully fabricated with these hierarchical porous carbons on hydrophilic ultrathin (200 μm) paper. An evaporation rate record of 7.87 kg m−2 h−1 and high energy conversion of 95.8% have been obtained under the concentrated solar intensity of 5 kW m−2. Our research leads to a new approach to converting halogenated plastics into environmentally friendly and useful porous carbon materials by simple, low-cost processes. It establishes and validates the concept of creating a sustainable and economic pathway to simultaneously recycle halogenated polymers, harvest solar energy and produce clean freshwater.

The construction of a high stability heterogeneous catalyst for privileged common catalysis is a benefit in regard to reuse and separation. Herein, a palladium diphenylphosphine-based hollow-shell-structured mesoporous catalyst (HS@PdPPh2@MSN) was prepared by immobilizing bis((diphenylphosphino)ethyltriethoxysilane)palladium acetate onto the inner wall of a mesoporous organicsilicane hollow shell, whose surface was protected by a –Si(Me)3 group. Electron microscopies confirmed its hollow-shell-structure, and structural analyses and characterizations revealed its well-defined single-site active species within the silicate network. As presented in this study, the newly constructed HS@PdPPh2@MSN enabled an efficient Suzuki-Miyaura cross-coupling reaction for varieties of substrates with up to 95% yield in mild conditions. Meanwhile, it could be reused at least five times with good activity, indicating its excellent stability and recyclability. Furthermore, the cost-effective and easily synthesized HS@PdPPh2@MSN made it a good candidate for employment in fine chemical engineering.

Nanocarbon materials have great potential for sustainable energy harvest and energy utilizations, such as solar thermal stream generation and interfacial evaporation. However, the evaporation rate is far too low for practical application. The technologies are not ready yet for industries requiring rapid, energy efficient and low cost evaporation processes such as distillation and sterilization. In this paper, flexible ultrathin graphene-carbon cloth (CC) based carbon-carbon composites have been prepared by in-situ electrochemical reduction of graphene oxide (rGO). The carbon-carbon composite materials demonstrated high performance in photothermal evaporation, more importantly, the all carbon-based devices can also be operated as low voltage Joule heating elements in wide temperature range up to 389 °C. Even with a very low voltage 3 V applied, the graphene-CC heater can reach a very high with very high heating speed up to 112 °C/sec, and a steady-state temperature up to 292 °C within 10 seconds only. The low voltage heater promises as the most effective solution for high-speed interfacial evaporations, its evaporation rate can reach upto 45.87 kg m−2 h−1, enhanced by one order of magnitude compared to the best solar power photothermal seawater desalination devices ever reported.

The liver plays a central role in regulating fat metabolism; however, it is not clear how the liver distributes the synthesized triglycerides (TGs) to storage and to the plasma.We have measured the relative distribution of TGs produced in the liver to storage and the plasma by means of U-(13)C(16)-palmitate infusion in anesthetized rabbits after an overnight fast.The fractional synthesis rates of TGs stored in the liver and secreted into the plasma were not significantly different (stored vs. secreted: 31.9 ± 0.8 vs. 27.7 ± 2.6%∙h(-1), p0.05). However, the absolute synthesis rates of hepatic stored and secreted TGs were 543 ± 158 and 27 ± 7 nmol∙kg(-1)∙min(-1) respectively, indicating that in fasting rabbits the TGs produced in the liver were predominately stored (92 ± 3%) rather than secreted (8 ± 3%) into the plasma. This large difference was mainly due to the larger pool size of the hepatic TGs which was 21 ± 9-fold that of plasma TGs. Plasma free fatty acids (FFAs) contributed 47 ± 1% of the FA precursor for hepatic TG synthesis, and the remaining 53 ± 1% was derived from hepatic lipid breakdown and possibly plasma TGs depending on the activity of hepatic lipase. Plasma palmitate concentration significantly correlated with hepatic palmitoyl-CoA and TG synthesis.In rabbits, after an overnight fast, the absolute synthesis rate of hepatic stored TGs was significantly higher than that of secreted due to the larger pool size of hepatic TGs. The net synthesis rate of TG was approximately half the absolute rate. Plasma FFA is a major determinant of hepatic TG synthesis, and therefore hepatic TG storage.

Acid rain is a serious environmental problem in the world. Soil columns were leached with simulated acid rain (SAR) at pH ranging from 2.5 to 5.6. The impact of SAR on the release of phenanthrene from red soil and its correlation with dissolved organic carbon (DOC) in eluates were investigated. The results showed that the leaching loss of phenanthrene was affected by both the leaching volume and acidity of SAR. When the leaching volume was less than 500 mm, the phenanthrene concentration in eluates decreased rapidly with increasing leaching volume, indicating a high rate of leaching loss at the beginning of leaching; then with continuous leaching, the phenanthrene concentration decreased slightly and reached zero when the leaching volume reached 875 mm. The lower pH of SAR was, the higher release rate of phenanthrene was. The change of DOC in eluates was similar to that of the phenanthrene concentration. The phenanthrene concentration had a significantly positive correlation with DOC in all eluates (the squared correlation coefficient R 2 varied between 0.952 and 0.997). Three-dimensional fluorescence analysis revealed that phenanthrene was associated with humic acid and fulvic acid, and was released with dissolved organic matters leached by SAR.

In this paper, we report the shape-controlled synthesis of MnWO 4 nanocrystals by a simple hydrothermal method without any surfactants and templates. The as-prepared powders were characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). It is found that MnWO 4 nanofibers, nanorods, nanoflakes, and nanoparticles can be selectively prepared by tuning the experimental conditions such as the pH values and precursors. This green chemistry method is simple and highly reproducible, which can be extended to the shape-controlled synthesis of other metal oxide nanocrystals.

cope Lysine (Lys) is a common limiting amino acids (AA) for humans and animals and plays an important role in cell proliferation and metabolism, while metabolism of Lys deficiency and its dipeptide is still obscure. Thus, this study mainly investigated the effects of Lys deficiency and Lys-Lys dipeptide on apoptosis and AA metabolism in vitro and in vivo models. Methods and results Lys deficiency induced cell-cycle arrest and apoptosis and upregulated Lys transporters in vitro and in vivo. SLC7A11, a cystine-glutamate antiporter, was markedly upregulated by Lys deficiency and then further mediated cystine uptake and glutamate release, which was negatively regulated by cystine and glutamate transporters. Meanwhile, Lys deprivation upregulated pept1 expression, which might improve Lys-Lys dipeptide absorption to compensate for the reduced Lys availability. Lys-Lys dipeptide alleviated Lys deficiency induced cell-cycle arrest and apoptosis and influenced AA metabolism. Furthermore, the mammalian target of rapamycin signal might be involved in sensing cellular Lys starvation and Lys-Lys dipeptide. Conclusions Altogether, these studies suggest that Lys deficiency impairs AA metabolism and causes apoptosis. Lys-Lys dipeptide serves as a Lys source and alleviates Lys deficiency induced cellular imbalance.

Copper and manganese based catalysts with different supports were prepared by impregnation method for toluene oxidation in the presence of water vapor. Their catalytic activity was tested in the absence and presence of water vapor. The results showed that the activity of catalysts CuMn(y)Ox/γ-Al2O3 was higher than that of catalysts CuOx/γ-Al2O3 and MnOx/γ-Al2O3. The presence of water vapor had a negative effect on catalytic activity due to the competition of water molecules with toluene molecules for adsorption on surface active sites. The durability to water vapor followed the order: CuMn(1)Ox/Cordierite > CuMn(1)Ox/TiO2 > CuMn(1)Ox/γ-Al2O3.

Lipopolysaccharide (LPS)-induced production of tumor necrosis factor (TNF)-α requires the recruitment of two pairs of adaptors to the Toll-like receptor 4 cytoplasmic domain. The contribution of one pair – Toll-interleukin-1 receptor domain-containing adaptor inducing interferon-β (TRIF) and TRIF-related adaptor molecule (TRAM) – to TNF-α expression is not well understood. To clarify this issue, we studied TRAM knockout bone marrow-derived macrophages (BMDM). LPS-stimulated TRAM-deficient BMDM had decreased TNF-α protein expression even at times when TNF-α mRNA levels were normal, suggesting impaired translation. Consistent with this idea, knockdown of TRAM in RAW264.7 macrophages decreased translation of a reporter controlled by the TNF-α 3′ untranslated region, while transfection of TRAM in HEK293T cells increased translation of this reporter. Also consistent with a role for TRAM in TNF-α translation, LPS-induced activation of MK2, a kinase involved in this process, was impaired in TRAM-deficient BMDM. TRIF did not increase translation of the TNF-α 3′ untranslated region reporter when expressed in HEK293T cells. However, BMDM that lacked functional TRIF produced reduced levels of TNF-α protein in response to LPS despite normal amounts of the mRNA. Unlike BMDM, LPS-stimulated TRAM-deficient peritoneal macrophages displayed equivalent reductions in TNF-α protein and mRNA. Our results indicate that TRAM- and TRIF-dependent signals have a previously unappreciated, cell type-specific role in regulating TNF-α translation.

l-α-glycerophosphorylcholine (GPC) was obtained by hydrolysis of lecithin extracted from eggs. FT-IR and 1H-NMR analysis indicated a successful preparation of GPC. Polylactide-based phospholipid polymer (PLLA-PC) was synthesized by ring-opening polymerization of l-lactide in the presence of GPC to improve the cell/material interfacial reaction of PLLA for tissue engineering applications. The yield of the reaction strongly depended on the reaction time. Values above 80% were obtained which are much higher than those reported in literature. Copolymers with the largest molecular weights were obtained at 122 °C for 48 h. The properties and biocompatibility of the PLLA-PC copolymers were characterized. Surface rearrangement was detected due to the dynamic molecular motion according to X-ray photoelectron spectroscopy data. Besides, increase in hydrophilicity and decreases in fibrinogen adsorption and platelet adhesion were observed due to the hydrophilic phosphorylcholine moieties in the copolymer.

Inflammation-induced jejunal cell death and oxidative stress have been observed in inflammatory bowel disease (IBD), but now, there is still no systematic animal model of jejunal oxidative stress for the evaluation of potential therapies. Thus, the purpose of this study was to evaluate the dynamic changes of pro-inflammatory cytokines and antioxidant expression on the jejunal inflammation. In this study, Hydrogen peroxide(H2O2, 10 ml/kg)was administrated intragastrically to mice in a single dose of 1%, 3%, or 5%. The incidence of death, histomorphometry, inflammatory cytokines (including TNF-α,IL-1β,and IL-5), and antioxidant genes were measured via RT-PCR. During the whole period, a massive infiltration of neutrophils was observed in the jejunum. Intragastric administration of H2O2 significantly up-regulated the expression of TNF-α,IL-1β, and IL-5 (P

Oxide precipitation behavior in heavily doped silicon after rapid thermal process (RTP) in Ar ambient was investigated. The samples were heavily B-, As- and Sb-doped wafers with a diameter of 150 mm, the concentration of interstitial oxygen was between 6 and 26 ppm. RTP temperatures were changed from 1200 to 1260 °C. The experiment showed that (1) High-density oxygen precipitates (above 10 5 /cm 2 ) were found in heavily B-doped wafer, denuded zone was found only at 1260 °C, (2) compared to the heavily B-doped wafers, the densities of oxygen precipitates in heavily As- and Sb-doped wafers were rather low. The formation of oxygen precipitates was restrained. The reason is discussed in this paper.

To investigate the effect of acute hyperinsulinemia and the resulting decrease in plasma free fatty acid (FFA) concentrations on intramuscular TG synthesis.U-(13)C(16)-palmitate was infused for 3 h in anesthetized rabbits after overnight food deprivation. Arterial blood and leg muscle were sampled during the tracer infusion. Plasma samples were analyzed for free and TG-bound palmitate enrichments and concentrations. The enrichments and concentrations of palmitoyl-CoA and palmitoyl-carnitine as well as the enrichment of palmitate bound to TG were measured in muscle samples. Fractional synthetic rate (FSR) of intramuscular TG was calculated using the tracer incorporation method. The rabbits were divided into a control group and a hyperinsulinemic euglycemic clamp group. Insulin infusion decreased the rate of appearance of plasma free palmitate (2.00±0.15 vs 0.68±0.20 μmol⋅kg(-1)⋅min(-1); P.001), decreased plasma FFA concentration (327±61 vs 72±25 nmol/mL; P.01), decreased the total concentration of intramuscular fatty acyl-CoA plus fatty acyl-carnitine (12.1±1.6 vs 7.0±0.7 nmol/g; P.05), and decreased intramuscular TG FSR (0.48±0.05 vs 0.21±0.06%/h; P.01) in comparison with the control group. Intramuscular TG FSR was correlated (P.01) with both plasma FFA concentrations and intramuscular fatty acyl-CoA concentrations.Fatty acid availability is a determinant of intramuscular TG synthesis. Insulin infusion decreases plasma and intramuscular fatty acid availability and thereby decreases TG synthesis.

Our goal was to assess the validity of the enrichments of plasma free palmitate and intramuscular (IM) fatty acid metabolites as precursors for calculating the IM triglyceride fractional synthetic rate. We infused U-13C16-palmitate in anesthetized rabbits for 3 h and sampled adductor muscle of legs using both freeze-cut and cut-freeze approaches. We found that IM free palmitate enrichment (0.70 ± 0.07%) was lower (P < 0.0001) than IM palmitoyl-CoA enrichment (2.13 ± 0.17%) in samples taken by the freeze-cut approach. The latter was close (P = 0.33) to IM palmitoyl-carnitine enrichment (2.42 ± 0.16%). The same results were obtained from the muscle samples taken by the cut-freeze approach, except the enrichment of palmitoyl-CoA (2.21 ± 0.08%) was lower (P = 0.02) than that of palmitoyl-carnitine (2.77 ± 0.17%). Plasma free palmitate enrichment was ∼2-fold that of IM palmitoyl-CoA enrichment and palmitoyl-carnitine enrichment (P < 0.001). These findings indicate that plasma free palmitate overestimated IM precursor enrichment owing to in vivo IM lipid breakdown, whereas IM free palmitate enrichment underestimated the precursor enrichment because of lipid breakdown during muscle sampling and processing. IM palmitoyl-carnitine enrichment was an acceptable surrogate of the precursor enrichment because it was less affected by in vitro lipid breakdown after sampling.