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The translocation of photosynthate carbohydrates, such as sucrose, is critical for plant growth and crop yield. Previous studies have revealed that sugar transporters, plasmodesmata and sieve plates act as important controllers in sucrose loading into and unloading from phloem in the vascular system. However, other pivotal steps for the regulation of sucrose movement remain largely elusive. In this study, characterization of two starch excesses in mesophyll (sem) mutants and dye and sucrose export assays were performed to provide insights into the regulatory networks that drive source-sink relations in rice. Map-based cloning identified two allelic mutations in a gene encoding a GLUCAN SYNTHASE-LIKE (GSL) protein, thus indicating a role for SEM1 in callose biosynthesis. Subcellular localization in rice showed that SEM1 localized to the plasma membrane. In situ expression analysis and GUS staining showed that SEM1 was mainly expressed in vascular phloem cells. Reduced sucrose transport was found in the sem1-1/1-2 mutant, which led to excessive starch accumulation in source leaves and inhibited photosynthesis. Paraffin section and transmission electron microscopy experiments revealed that less-developed vascular cells (VCs) in sem1-1/1-2 potentially disturbed sugar movement. Moreover, dye and sugar trafficking experiments revealed that aberrant VC development was the main reason for the pleiotropic phenotype of sem1-1/1-2. In total, efficient sucrose loading into the phloem benefits from an optional number of VCs with a large vacuole that could act as a buffer holding tank for sucrose passing from the vascular bundle sheath.

Chloroplasts are the center of plant life activities including photosynthesis, growth and development, and abiotic stress response. Chloroplast development and biogenesis in rice have been studied in detail, but how does abiotic stress affect chloroplasts is less studied. We obtained an albino mutant, alm1, whose chlorophyll content was greatly decreased. Transmission electron microscopy showed that chloroplast development in alm1 was blocked, especially in thylakoid-like structures, which could not form normally. The ALM1 gene encodes a chloroplast-localized superoxide dismutase. Full-length ALM1 successfully restored the non-albino phenotype, and in knockout lines, the albino phenotype reappeared. The ALM1 gene is expressed mainly in young leaves. alm1 plants died as a consequence of excessive reactive oxygen accumulation after the third-leaf stage. A series of biochemical assays verified that ALM1 interacted with the OsTrxz protein, which is one of the components of plastid-encoded RNA polymerase (PEP) complexes. A western blot experiment indicated that ALM1 played an important role in stabilizing OsTrxz in rice. An overexpression test of ALM1 revealed that ALM1 can increase drought resistance by removing excess reactive oxygen in rice seedlings. This study suggests that ALM1 not only participates in rice chloroplast biogenesis, but also increases rice stress resistance by scavenging excess reactive oxygen.

Prussian Blue Analogues (PBAs) are promising electrocatalysts for oxidation reactions due to their binary metal composition and tuneable redox properties. Herein, we report the generation of coordinative unsaturated metal sites in pulse electrodeposited (PED) CoFe PBAs for the oxidation of 5-hydroxymethylfurfural (HMF). The high reactivity by unsaturated metal sites, thoroughly characterized by a suite of spectroscopic techniques, results in a catalyst with superior activity towards the oxidation of HMF to 2,5 furandicarboxylic acid (FDCA).

Biomass pretreatments represent a necessary route to overcome the natural physico-chemical barriers of recalcitrant feedstocks. However, current biomass pretreatments generally result in generation of various inhibitors (such as furfural derived from pentose), which could inhibit cell growth and decrease biofuel productivity. This study aims to understand the impact of furfural on hydrogen-producing Enterobacter aerogenes in dark fermentation of glucose. When adding 5 mM furfural in fermentation, hydrogen yield unexpectedly increased to 193.7 mL/g compared to 163.5 mL/g (in the absence of furfural); and the associated peak hydrogen production rate increased by 126%. This phenomenon from a thermodynamic perspective was due to the fact that furfural at a low concentration contributes to hydrogen production. A higher concentration of furfural (30 mM) significantly decreased hydrogen yield to 109.1 mL/g owing to severe cell membrane damage. The indicator of half-maximal inhibitory concentration was calculated as 32.5 mM. A postulated metabolic response of E. aerogenes to furfural is that the degradation of low concentrations of furfural (5 mM) involved a reduction reaction of furfural to hydrogen and furfuryl alcohol. However, a high concentration of furfural (30 mM) caused significant cell disfunction in normal metabolism, causing increased deformation degree in bacterial surface.

Remorins (REMs) play an important role in the ability of plants to adapt to adverse environments. PeREM6.5, a protein of the REM family in Populus euphratica (salt-resistant poplar), was induced by NaCl stress in callus, roots and leaves. We cloned the full-length PeREM6.5 from P. euphratica and transformed it into Escherichia coli and Arabidopsis thaliana. PeREM6.5 recombinant protein significantly increased the H+-ATPase hydrolytic activity and H+ transport activity in P. euphratica plasma membrane (PM) vesicles. Yeast two-hybrid assay showed that P. euphratica REM6.5 interacted with RPM1-interacting protein 4 (PeRIN4). Notably, the PeREM6.5-induced increase in PM H+-ATPase activity was enhanced by PeRIN4 recombinant protein. Overexpression of PeREM6.5 in Arabidopsis significantly improved salt tolerance in transgenic plants in terms of survival rate, root growth, electrolyte leakage and malondialdehyde content. Arabidopsis plants overexpressing PeREM6.5 retained high PM H+-ATPase activity in both in vivo and in vitro assays. PeREM6.5-transgenic plants had reduced accumulation of Na+ due to the Na+ extrusion promoted by the H+-ATPases. Moreover, the H+ pumps caused hyperpolarization of the PM, which reduced the K+ loss mediated by the depolarization-activated channels in the PM of salinized roots. Therefore, we conclude that PeREM6.5 regulated H+-ATPase activity in the PM, thus enhancing the plant capacity to maintain ionic homeostasis under salinity.

Summary Salt stress is an important environmental cue impeding poplar nitrogen nutrition. Here, we characterized the impact of salinity on proton‐driven nitrate fluxes in ectomycorrhizal roots and the importance of a Hartig net for nitrate uptake.We employed two Paxillus involutus strains for root colonization: MAJ, which forms typical ectomycorrhizal structures (mantle and Hartig net), and NAU, colonizing roots with a thin, loose hyphal sheath. Fungus‐colonized and noncolonized Populus × canescens were exposed to sodium chloride and used to measure root surface pH, nitrate (NO 3 −) flux and transcription of NO3 − transporters (NRTs; PcNRT1.1, ‐1.2, ‐2.1), and plasmalemma proton ATPases (HAs; PcHA4, ‐8, ‐11). Paxillus colonization enhanced root NO 3 − uptake, decreased surface pH, and stimulated NRTs and HA4 of the host regardless the presence or absence of a Hartig net. Under salt stress, noncolonized roots exhibited strong net NO 3 − efflux, whereas beneficial effects of fungal colonization on surface pH and HAs prevented NO 3 − loss. Inhibition of HAs abolished NO 3 − influx under all conditions.We found that stimulation of HAs was crucial for the beneficial influence of ectomycorrhiza on NO 3 − uptake, whereas the presence of a Hartig net was not required for improved NO 3 − translocation. Mycorrhizas may contribute to host adaptation to salt‐affected environments by keeping up NO 3 − nutrition.

The method of high temperature physical vapor transport (HTPVT) is an available approach to prepare silicon carbide (SiC) ceramics with high density and high purity. In the present work, α-SiC (6H-SiC) and β-SiC (3C-SiC) powders were used as starting materials respectively to fabricate SiC ceramics with HTPVT process, and the effects of starting materials on nucleation, density, microstructure and mechanical properties of SiC ceramics were investigated. It showed that at high temperature, the decomposition rate of β-SiC was higher than that of α-SiC, and at the initial nucleation stage, the average grain size of SiC crystal obtained with β-SiC starting materials was smaller than that with α-SiC starting materials, because higher vapour pressure of gas phase which decomposed by β-SiC starting materials facilitated nucleation and growth of SiC grains. Density of the resulted SiC ceramics using α-SiC and β-SiC as starting materials was 3.16 g·cm-3 and 3.17 g·cm-3, indicating close values, while, using β-SiC as the starting materials, the grain size was smaller, consequently, the flexure strength was higher. Increasing growth temperature from 2200°C to 2300°C, the densities and the flexure strength of the SiC ceramics using either α-SiC or β-SiC were decreased.

Developing a highly efficient bifunctional electrocatalyst for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) remains significant for metal–air battery progress. Among all candidates, non-precious transition metal composite materials with the appropriate components and nanostructures are promising for the ORR and OER. Herein, a composite comprising a CoMn alloy coated with N-doped carbon and MnO is synthesized by a facile strategy involving the annealing of a Prussian blue analogue. The derived heterogeneous composite includes the benefits of a CoMn alloy, N-doped carbon and MnO, giving a low onset potential (0.91 V), positive half-wave potential (0.76 V) and large limiting current density (5.8 mA cm−2). The enhanced ORR activity can be attributed to the optimal surface electronic configuration of the alloy, which facilitates intermediate dissociation, in combination with heterojunctions, which favor charge transfer from the alloy and oxide. In addition, the electrocatalyst displays promising activity for the OER with an onset potential of 1.53 V and a low potential of 1.65 V at 10 mA cm−2, highlighting its prospect as an efficient bifunctional electrocatalyst.

This work aimed at investigating the interactive effects of salt-signaling molecules, i.e., ethylene, extracellular ATP (eATP), H2O2, and cytosolic Ca2+ ([Ca2+]cyt), on the regulation of K+/Na+ homeostasis in Arabidopsis thaliana. The presence of eATP shortened Col-0 hypocotyl length under no-salt conditions. Moreover, eATP decreased relative electrolyte leakage and lengthened root length significantly in salt-treated Col-0 plants but had no obvious effects on the ethylene-insensitive mutants etr1-1 and ein3-1eil1-1. Steady-state ionic flux kinetics showed that exogenous 1-aminocyclopropane-1-carboxylic acid (ACC, an ethylene precursor) and eATP-Na2 (an eATP donor) significantly increased Na+ extrusion and suppressed K+ loss during short-term NaCl treatment. Moreover, ACC remarkably raised the fluorescence intensity of salt-elicited H2O2 and cytosolic Ca2+. Our qPCR data revealed that during 12 h of NaCl stress, application of ACC increased the expression of AtSOS1 and AtAHA1, which encode the plasma membrane (PM) Na+/H+ antiporters (SOS1) and H+-ATPase (H+ pumps), respectively. In addition, eATP markedly increased the transcription of AtEIN3, AtEIL1, and AtETR1, and ACC treatment of Col-0 roots under NaCl stress conditions caused upregulation of AtRbohF and AtSOS2/3, which directly contribute to the H2O2 and Ca2+ signaling pathways, respectively. Briefly, ethylene was triggered by eATP, a novel upstream signaling component, which then activated and strengthened the H2O2 and Ca2+ signaling pathways to maintain K+/Na+ homeostasis under salinity.

Two novel Cd-based coordination polymers Cd(H2BCP)2(phen)2 1 and {[Cd6(BCP)4(phen)3]·2H2O}n 2 (Phen=1,10-phenanthroline) have been hydrothermally synthesized from a combination of 4-(phosphonomethyl) benzoic acid 4-HOOCC6H4CH2PO3H2 (H3BCP) and 1,10-phenanthroline. The X-ray crystal structure analyses revealed that 1 is a 0D mononuclear molecular structure and 2 is a 3D structure existing the novel Cd6 cluster unit. It is worth mentioning that 1 and 2 have the same constitutional units, namely the Cd ion, H3BCP ligand and second ligand- Phen. However, their structures are different and it results from the different solution pH value. In order to explore the structural characteristics, FTIR, photo-luminescent and solid UV-Vis spectra are employed. Synthesis and properties of two novel Cd-based coordination polymers Cd(H2BCP)2(phen)2 1 and {[Cd6(BCP)4(phen)3]·2H2O}n 2 are reported. It is worth mentioning that 1 is zero-dimensional structure and forms super-molecular layers via O–H···O under the condition of solution pH = 2.1, 2 is a three-dimensional framework and contains the novel Cd6 cluster unit under the condition of solution pH = 5. So controlling the pH of the solution plays an important role in the structure of the compound.

Fermentative production of biohydrogen and volatile fatty acids (VFAs) from advanced feedstocks such as seaweed provides opportunities in the carbon-neutral bioeconomy. The gap in the state of the art exists in overcoming both the low fermentation efficiency associated with the rigid structure of seaweed and the inefficient metabolic electron transfer within the microbial communities. This study evaluated the effects of carbonaceous additives (such as graphene and various biochars) on biohydrogen fermentation of glucose, cellulose, and the brown seaweed Laminaria digitata. The impacts of carbonaceous additives varied significantly in terms of hydrogen production, VFA profiles, and microbial communities. Graphene and wood-derived biochar (Wood_Biochar) were shown to be superior to draff-derived biochars. In the fermentation of L. digitata, graphene and Wood_Biochar significantly reduced the lag-phase time by 47% and 49%, respectively. Microbial analysis revealed that the enhanced fermentation was ascribed to the enrichment of Thermoanaerobacterium genus in response to carbonaceous additives. Kinetic correlations between the fermentation parameters and the properties of the additives suggested that the graphitic structure and electrical conductivity might play a crucial role in facilitating the fermentation. The mechanisms might be ascribed to (1) the supported biofilm growth and (2) enhancement in microbial electron transfer induced by the additives.

The title complex Cd/4-(phosphonomethyl) benzoic acid 4-HOOCC6H14CH2PO3(H3BCP) with 1,10-phenanthroline has been hydrothermally synthesized directly as [Cd3(BCP)2(phen)]·H2O 1 (phen = 1,10-phenanthroline). The crystal structure was determined by single-crystal X-ray diffraction with the following data: triclinic P-1. The complex is a two-dimensional layer structure. Interestingly, the one-dimensional cluster chain is composed of the novel repeated La4 cluster units connected by two Cd3 ions. The adjacent cluster chains link to be 2D layer structure by the coordination interaction of oxygen atoms of the carboxyl with the Cd3 ions of the adjacent chains. It is worthy of mentioning that IR, photo-luminescent and solid UV–Vis spectrum are employed in order to explore the structural characteristics.

Future renewable energy conversion requires advanced electrocatalysis technologies for hydrogen production, fuel cells, and metal-air batteries. Highly efficient trifunctional nonprecious electrocatalysts are a critical precious metal replacement for the economically viable electrocatalysis of oxygen reduction and water splitting, both of which are a triphase electrode process. Electrocatalysts with a refined porous structure and active composition beneficial for three-phase reactions are broadly pursued. Herein, a highly promising trifunctional spherical Murray assembly of Co-N-C nanoparticles was derived from low-cost Prussian blue analogues for the oxygen reduction reaction and water splitting. The Murray-type architecture with a tunable porous hierarchy for efficient mass transfer and the combination of a Co-N-C active composition are key for the improved electrocatalytic performance. Acid-leaching produced an optimized Murray-type durable and methanol-tolerant Co-N-C electrocatalyst that achieved an onset potential of 0.94 V [vs reversible hydrogen electrode (RHE)] and a half wave potential of 0.84 V (vs RHE) as well as a large diffusion-limited current density of 5.7 mA cm-2 for the oxygen reduction reaction, which is comparable to Pt/C. In addition, it displayed low onset overpotentials of ∼150 and ∼350 mV corresponding to the hydrogen evolution reaction and oxygen evolution reaction, respectively, highlighting its great potential to be used in overall water splitting with a total splitting voltage of 1.73 V. This work highlights the importance of Murray-type electrocatalysts for multiphase energy-related reactions.

High-performance and low-cost bifunctional electrocatalysts play crucial roles in oxygen reduction and evolution reactions. Herein, a novel three-dimensional (3D) bifunctional electrocatalyst was prepared by embedding CoO nanoparticles into nitrogen and sulfur co-doped carbon nanofiber networks (denoted as CoO@N/S-CNF) through a facile approach. The carbon nanofiber networks were derived from a nanostructured biological material which provided abundant functional groups to nucleate and anchor nanoparticles while retaining its interconnected 3D porous structure. The composite possesses a high specific surface area and graphitization degree, which favors both mass transport and charge transfer for electrochemical reaction. The CoO@N/S-CNF not only exhibits highly efficient catalytic activity towards oxygen reduction reaction (ORR) in alkaline media with an onset potential of about 0.84 V, but also shows better stability and stronger resistance to methanol than Pt/C. Furthermore, it only needs an overpotential of 1.55 V to achieve a current density of 10 mA cm−2, suggesting that it is an efficient electrocatalyst for oxygen evolution reaction (OER). The ΔE value (oxygen electrode activity parameter) of CoO@N/S-CNF is calculated to be 0.828 V, which demonstrates that the composite could be a promising bifunctional electrocatalyst for both ORR and OER.

A kinetic study of dimethyl ether (DME) combustion over Pt/ZSM-5 was performed below 423 K. Power law model and Langmuir-Hinshelwood model were established to predict the reaction rate. Reaction orders for DME and O 2 were 0.28 and 2.30, respectively. Activation energies for the two models were 99.35 and 109.30 kJ/mol. The reaction orders and adsorption constants suggested DME was more strongly adsorbed on Pt/ZSM-5 than O 2 at low temperatures. The reliability of the models was confirmed by the comparison between the predicted and experimental conversions of DME.

n-Heptane combustion was conducted in packed-bed micro combustors using two catalyst layouts, namely, continuous (type A) and two-sectional (type B) types. Cerium–Zirconium solid solution-supported platinum was adopted as catalyst. The two combustors demonstrated distinct combustion characteristics owing to their different catalyst layouts. Type B significantly expanded the upper limit of Reynolds number (Re) of stable combustion, maintaining stable combustion at Re = 1500 under fuel-rich conditions at an equivalent ratio of Φ = 1.6. Type A was more advantageous at low Re values, and the lower Re limit was reduced to 12. Types A and B displayed a single peak and a bimodal distribution of wall temperature, respectively. The bimodal distribution in type B not only slowed down the variation in wall temperature with Re but also proved that catalyst-free homogenous combustion occurred in the throat. As a result of the different combustion processes, type A showed different variation trends of products along the length compared with type B. Moreover, the conversion rates of the two types reached their maximum values (84.4% and 88.3%) at Re = 160. High conversion rate of type B was attributed to heterogeneous/homogenous combustion and long heat reflux zones.

Oil-field wastewater from polymer flooding (OWPF) is difficult to deal with because it contains a high concentration of partially hydrolyzed polyacrylamide (HPAM), which stabilizes the wastewater. Coagulation–flocculation with polyepicholorohydrin–dimethylamine (EPI-DMA) and polymeric aluminum ferric chloride (PAFC) was used to optimize the treatment of OWPF. HPAM and COD removal were optimized using the response surface method (RSM), based on the Box–Behnken design (BBD). The variables EPI-DMA dose, PAFC dose, and pH were selected as the factors in the RSM to investigate their individual and interaction effects on the response values, HPAM and COD removal efficiencies. The results showed that HPAM and COD removal efficiencies of 95.4 and 85.7%, respectively, could be reached using 0.65 mg/L EPI-DMA, 924 mg/L PAFC, and pH 5.51. Fourier transform infrared spectroscopy, zeta potential, particle size analysis, scanning electron microscopy, and energy dispersive spectroscopy were used to study the mec...

The combustion of ethanol and dimethyl ether (DME) was performed over Pt/ZSM-5 catalyst in a packed-bed reactor to investigate the combustion characteristics and catalyst deactivation. Results showed that the CO2 yield and wall temperature for the combustion of DME were higher than those for the combustion of ethanol. The maximum CO2 yield for both fuels surpassed 72%. After 48 h of continuous combustion, CO2 yields of DME and ethanol decreased by 13.8% and 38.9%, respectively, attributed to the agglomeration of Pt and the formation of carbonaceous deposits on the catalyst. Transmission electron microscopy images showed considerable Pt agglomeration after ethanol combustion. Temperature-programmed oxidation results revealed two types of carbonaceous deposits with oxidation temperatures of 225 and 345 °C after DME combustion, but only the former type was detected after ethanol combustion. X-ray photoelectron spectra revealed that the mainly increased surface carbonaceous species were C C/C H and O C O after the combustion of ethanol and DME, respectively.

Electrocatalysts play a vital role in electrochemical water-splitting for hydrogen production. Here, we report the preparation of three-dimensional molybdenum phosphide (MoP) as a non-precious-metal electrocatalyst for the hydrogen evolution reaction (HER) by using cheap sponge (polyurethane, PU) as a sacrificial template. The obtained 3D MoP not only has large surface area, but also possesses a porous and channel-rich structure, in which the side walls of the pores are composed of refined nanoparticles. The 3D MoP sponge was used as a bulky and binder-free HER electrode and exhibited excellent catalytic activity in an acidic electrolyte (achieving 10 and 20 mA cm−2 at an overpotential of 105 and 155 mV, respectively). In addition, this novel bulky HER electrode showed a relatively small Tafel slope of 126 mV dec−1, a high exchange current density of 3.052 mA cm−2, and a faradaic efficiency of nearly 100%. Furthermore, this bulky electrode revealed high tolerance and durability both under acidic and basic conditions, maintaining 96% and 93% of its initial catalytic activity after continuous testing for 60 000 s. Thus, our work paves a feasible way of fabricating a cheap and highly efficient HER electrode on a large-scale for electrochemical water-splitting technology.

Electrocatalysts play a vital role in electrochemical water-splitting for hydrogen production. However, searching for low-cost and earth-abundant electrocatalysts remains a challenge. In this study, we report the synthesis of mesoporous molybdenum phosphide hemispheres as electrocatalysts and their direct growth on a carbon cloth (MoP-HS@CC) to create a self-supported electrode for efficient hydrogen evolution. The obtained MoP-HS@CC was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and nitrogen adsorption–desorption. MoP-HS@CC not only has a large surface area, it also possesses rich porosity. In addition, as a binder-free electrode for hydrogen evolution, MoP-HS@CC exhibits a low onset overpotential of 30 mV, a small Tafel slope of 61 mV dec−1, and a large exchange current density of 0.438 mA cm−2 in acidic electrolytes. It affords current densities of 10 and 100 mA cm−2 at overpotentials of 87 and 195 mV, respectively. Moreover, MoP-HS@CC shows a strong tolerance to working environment both in acidic and alkaline conditions. This study essentially offers a simple and viable strategy for preparing highly efficient and flexible electrodes on a large-scale for electrochemical water-splitting technology.

Non-invasive micro-test techniques (NMT) were used to analyze NaCl-altered flux profiles of K+, Na+, and H+ in roots and effects of NaHS (a H2S donor) on root ion fluxes in two contrasting poplar species, Populus euphratica (salt-resistant) and Populus popularis (salt-sensitive). Both poplar species displayed a net K+ efflux after exposure to salt shock (100 mM NaCl), as well as after short-term (24 h), and long-term (5 d) saline treatment (50 mM NaCl, referred to as salt stress). NaHS (50 M) restricted NaCl-induced K+ efflux in roots irrespective of the duration of salt exposure, but K+ efflux was not pronounced in data collected from the long-term salt stress treatment of P. euphratica. The NaCl-induced K+ efflux was inhibited by a K+ channel blocker, tetraethylammonium chloride (TEA) in P. popularis root samples, but K+ loss increased with a specific inhibitor of plasma membrane H+-ATPase, sodium orthovanadate, in both poplar species under long-term salt stress and NaHS treatment. This indicates that NaCl-induced K+ loss was through depolarization-activated K+ channels. NaHS caused increased Na+ efflux and a corresponding increase in H+ influx for poplar roots subjected to both the short- and long-term salt stress. The NaHS-enhanced H+ influx was not significant in P. euphratica samples subjected to short term salt stress. Both sodium orthovanadate and amiloride (a Na+/H+ antiporter inhibitor) effectively inhibited the NaHS-augmented Na+ efflux, indicating that the H2S-enhanced Na+ efflux was due to active Na+ exclusion across the plasma membrane. We therefore conclude that the beneficial effects of H2S probably arise from upward regulation of the Na+/H+ antiport system (H+ pumps and Na+/H+ antiporters), which promote exchange of Na+ with H+ across the plasma membrane and simultaneously restricted the channel-mediated K+ loss that activated by membrane depolarization.

Crystalline structure and surface features of metal oxide catalyst have important influence on catalysis, however, no research work has focused on the relationship between the oxygen evolution reaction (OER) catalytic activity and plane effect of Co3O4 nanocrystals. In this work, Co3O4 nanorods and nanocubes with different dominant exposed nanocrystalline planes ({110} and {100}) were synthesized to investigate the plane effects of Co3O4 nanocrystalline on the OER activity. Results show that the surface Co3 + species of the Co3O4 crystal should be the active sites for OER catalysis.

Purpose Eslicarbazepine (ESL), Lacosamide (LAC), Perampanel (PER) and Brivaracetam (BRV), have recently been marketed as third-generation antiepileptic drugs (AEDs). We conducted a meta-analysis to indirectly compare overall efficacy and tolerability between third-generation AEDs in uncontrolled focal epilepsy. Methods We performed an online database search using Pubmed, Embase, Cochrane Online Library, and Clinicaltrial.gov for all available randomized controlled trials (RCTs) that investigated the therapeutic effects over a range of AED doses versus placebo. We then compared clinical efficacy and tolerability between these newer AEDs using Indirect Treatment Comparison software. Results Nineteen RCTs with a total of 7245 patients were included in our study. There were no significant differences in the risk difference of 50% responder rates and seizure free rates between third generation AEDs, regardless of dose. The risk of treatment emergent adverse events was significantly higher with ESL and PER treatment compared to BRV at all doses combined. Withdrawal rates due to adverse events were also significantly higher in patients treated with the highest doses of LAC and PER versus BRV, while treatment with ESL or LAC was related to higher withdrawal rates versus BRV when all doses were combined. Conclusions Our analysis suggested there were no significant differences in efficacy between third generation AEDs in uncontrolled focal epilepsy. BRV may have the best tolerability profile. The other AEDs were associated with a higher risk for intolerable adverse, especially when taken at a high doses. The results from these indirect comparisons warrant further examination and verification through future well-designed trials.

We investigated the effects of salt-sensitive signaling molecules on ionic fluxes and gene expression related to K+/Na+ homeostasis in a perennial herb, Glycyrrhiza uralensis, during short-term NaCl stress (100 mM, 24 h). Salt treatment caused more pronounced Na+ accumulation in root cells than in leaf cells. Na+ ions were mostly compartmentalized in vacuoles. Roots exposed to NaCl showed increased levels of extracellular ATP (eATP), cytosolic Ca2+, H2O2, and NO. Steady-state flux recordings revealed that these salt-sensitive signaling molecules enhanced NaCl-responsive Na+ efflux, due to the activated Na+/H+ antiport system in the plasma membrane (PM). Moreover, salt-elicited K+ efflux, which was mediated by depolarization-activated cation channels, was reduced with the addition of Ca2+, H2O2, NO, and eATP. The salt-adaptive effects of these molecules (Na+ extrusion and K+ maintenance) were reduced by pharmacological agents, including LaCl3 (a PM Ca2+ channel inhibitor), DMTU (a reactive oxygen species scavenger), cPTIO (an NO scavenger), or PPADS (an antagonist of animal PM purine P2 receptors). RT-qPCR data showed that the activation of the PM Na+/H+ antiport system in salinized roots most likely resulted from the upregulation of two genes, GuSOS1 and GuAHA, which encoded the PM Na+/H+ antiporter, salt overly sensitive 1 (SOS1), and H+-ATPase, respectively. Clear interactions occurred between these salt-sensitive agonists to accelerate transcription of salt-responsive signaling pathway genes in G. uralensis roots. For example, Ca2+, H2O2, NO, and eATP promoted transcription of GuSOS3 (salt overly sensitive 3) and/or GuCIPK (CBL-interacting protein kinase) to activate the predominant Ca2+-SOS signaling pathway in salinized liquorice roots. eATP, a novel player in the salt response of G. uralensis, increased the transcription of GuSOS3, GuCIPK, GuRbohD (respiratory burst oxidase homolog protein D), GuNIR (nitrate reductase), GuMAPK3, and GuMAPK6 (the mitogen-activated protein kinases 3 and 6). Moreover, GuMAPK3 and GuMAPK6 expression levels were enhanced by H2O2 in NaCl-stressed G. uralensis roots. Our results indicated that eATP triggered downstream components and interacted with Ca2+, H2O2, and NO signaling to maintain K+/Na+ homeostasis. We propose that a multiple signaling network regulated K+/Na+ homeostasis in NaCl-stressed G. uralensis roots.

This study was conducted to develop a population pharmacokinetic (PopPK) model for vancomycin and to detect the significant covariates that influence the PopPKs to facilitate individualized therapy for Chinese pediatric patients.Patients ≤ 10 years old who received vancomycin for ≥ 72 hours between 2007 and 2010 were analyzed using a nonlinear mixed-effects modeling approach (-NONMEM). A one-compartment model with first-order elimination was chosen to depict the data. Stepwise covariate modeling (SCM) was employed to detect significant covariates and obtain a final model. Internal validation methods, including bootstrapping and visual predictive checks (VPC), were applied to evaluate the robustness and predictive power of the final model.The analysis included 54 pediatric inpatients with 128 serum concentration samples. The mean age (range) was 124.30 (1.29 - 541.4) weeks, the mean weight was 10.36 (1.4 - 33.5) kg, and the mean baseline serum creatinine (Scr) level was 0.39 (0.15 - 1.32) mg/dL. Pneumonia was the most common indication for vancomycin therapy (33.33%), followed by bacteremia (25.93%), and meningitis (22.22%). A PopPK model of vancomycin in Chinese pediatric patients was developed. Postnatal age (PNA) significantly affected the vancomycin clearance (CL) of pediatric patients, and the influence was described using the sigmoid maximum effect (Esubmax/sub) model. The effect of body weight (WT) on CL and volume of distribution (V) was investigated using an allometric scaling equation. The final model parameters were CL(L/h) = 11.75×[PNAsup0.4672/sup/(PNAsup0.4672/sup+33.3sup0.4672/sup)]×(WT/70)sup0.75/sup×esup0.362/supand V(L) = 54.49×WT/70×esup0.6711/sup. The model evaluation results suggested robustness and good predictability of the final model.A PopPK model of vancomycin for Chinese pediatric patients was developed in this study. The significant covariates distinguished in the final model can provide helpful information to facilitate individualized therapy for Chinese pediatric patients. .

The halophilic methanoarchaeon Methanohalophilus portucalensis FDF1T possesses the ability to synthesize the osmolyte betaine from its precursor, glycine, in response to extracellular salt stress through a three-step transmethylation process. Analysis of recombinant glycine sarcosine N-methyltransferase (rGSMT) and recombinant sarcosine dimethylglycine N-methyltransferase (rSDMT) from Escherichia coli indicated that betaine synthesis is rate-limited by rGSMT and is constitutively activated by rSDMT. Therefore, it is of interest to purify native GSMT from Methanohalophilus portucalensis to further compare its enzymatic characteristics and kinetics with rGSMT. In this study, native GSMT was purified through DEAE ion exchange and gel filtration chromatography with 95% purity. The enzymatic characteristics of GSMT and rGSMT showed similar trends of activities that were activated by high concentrations of monovalent cations. Both were feedback-inhibited by the end product, betaine, and competitively inhibited by S-adenosylhomocysteine (SAH). Native GSMT was 2-fold more sensitive to SAH than rGSMT. Notably, comparison of the kinetic parameters illustrated that the turnover rate of glycine methylation of GSMT was promoted by potassium ions, whereas rGSMT was activated by increasing protein-glycine binding affinity. These results suggest that GSMT and rGSMT may have different levels of post-translational modifications. Our preliminary mass spectrometry evidence indicated that there was no detectable phosphosite on GSMT after the complicated purification processes, whereas purified rGSMT still possessed 23.1% of its initial phosphorylation level. We believe that a phosphorylation-mediated modification may be involved in the regulation of this energy consuming betaine synthesis pathway during the stress response in halophilic methanoarchaea.

Sodium chloride (NaCl) induced expression of a jacalin-related mannose-binding lectin (JRL) gene in leaves, roots, and callus cultures of Populus euphratica (salt-resistant poplar). To explore the mechanism of the PeJRL in salinity tolerance, the full length of PeJRL was cloned from P. euphratica and was transformed into Arabidopsis. PeJRL was localized to the cytoplasm in mesophyll cells. Overexpression of PeJRL in Arabidopsis significantly improved the salt tolerance of transgenic plants, in terms of seed germination, root growth, and electrolyte leakage during seedling establishment. Under NaCl stress, transgenic plants retained K+ and limited the accumulation of Na+. PeJRL-transgenic lines increased Na+ extrusion, which was associated with the upward regulation of SOS1, AHA1, and AHA2 genes encoding plasma membrane Na+/proton (H+) antiporter and H+-pumps. The activated H+-ATPases in PeJRL-overexpressed plants restricted the channel-mediated loss of K+ that was activated by NaCl-induced depolarization. Under salt stress, PeJRL&ndash, transgenic Arabidopsis maintained reactive oxygen species (ROS) homeostasis by activating the antioxidant enzymes and reducing the production of O2&minus, through downregulation of NADPH oxidases. Of note, the PeJRL-transgenic Arabidopsis repressed abscisic acid (ABA) biosynthesis, thus reducing the ABA-elicited ROS production and the oxidative damage during the period of salt stress. A schematic model was proposed to show the mediation of PeJRL on ABA response, and ionic and ROS homeostasis under NaCl stress.

Three rare earth compounds with 3-methylbenzoic acid (HMeBA) have been hydrothermally synthesized directly: Gd 2 (MeBA) 6 (o-Phen) 2 1 (o-Phen = o-phenanthroline), [Gd 2 (MeBA) 6 (2,2′-bpy)] n 2 (2,2′-bpy = 2,2′-bipyridine) and Gd (MeBA) 3 ·(4,4′-bpy) 0.5 3 (4,4′-bpy = 4,4′-bipyridine). These crystal structures were determined by single-crystal X-ray diffraction with the following data: 1 : monoclinic, Cc ; 2 : monoclinic, P 2 1 / n ; 3 : Triclinic, P − 1. The compound 1 is a zero-dimensional Bi-nuclear oligomer and ligand -o- phenanthroline participates in the coordination; the compound 2 is a one-dimensional chain and the second ligand -2,2′-bpy participates in coordinating with the Gd ion; in particular, due to the existence of the second ligand -4,4′-bpy which acts as the bridge, the compound 3 is the two-dimensional layer. Additionally, in order to explore the structural characteristic, photo-luminescent and the 2D-IR correlation spectroscopy containing the temperature-induced structural variations and magnetism-induced structural variations are used.

Graft copolymerization of SBS in the form of sodium ionomer with acrylamide in emulsion using benzoyl peroxide as initiator and sodium ionomer of maleated SBS as a self-emulsifier, which can form a stable cyclohexane/water emulsion with AM without using any other emulsifier, was carried out. Factors affecting the graft copolymerization were studied. The grafting % can reach about 15%. Emulsifying properties of sodium ionomer of maleated SBS and the graft copolymer, as well as the compatibilizing effect of the graft copolymer in blending polyvinyl chloride (PVC) with SBS, were studied. The sodium ionomer of maleated SBS, the graft copolymers, and the blends were characterized with IR and DSC. The results showed that water absorbency and emulsifying volume increase obviously after graft copolymerization with AM. 0.2 g of the graft copolymer containing 14 wt % PAM grafts can emulsify a mixture of 30 mL toluene and 70 mL water completely. The graft copolymer can be used as an effective compatibilizer in the blending of PVC and SBS, more effective than the sodium ionomer of maleated SBS. Only 2 wt % of the copolymer based on the blend used in blending is enough to raise the tensile strength three times. The blends with weigh ratios of PVC/SBS at 3/7–4/6 in the presence of the graft copolymer behave as thermoplastic elastomers with a tensile strength of 14 MPa, an ultimate elongation of 750%, and a permanent set of 17%. Glass transition temperatures of the blend shifted inward in the presence of the graft copolymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1248–1253, 2005

Serratia marcescens SS-1 produces at least four N-acylhomoserine lactones (AHLs) which were identified using high-resolution mass spectrometry and chemical synthesis, as N-(3-oxohexanoyl) homo-serine lactone (3-oxo-C6-HSL), N-hexanoyl- (C6-HSL), N-heptanoyl (C7-HSL) and N-octanoyl- (C8-HSL) homoserine lactone. These AHLs are synthesized via the LuxI homologue SpnI, and regulate via the LuxR homologue SpnR, the production of the red pigment, prodigiosin, the nuclease, NucA, and a biosurfactant which facilitates surface translocation. spnR overexpression and spnR gene deletion show that SpnR, in contrast to most LuxR homologues, acts as a negative regulator. spnI overexpression, the provision of exogenous AHLs and spnI gene deletion suggest that SpnR is de-repressed by 3-oxo-C6-HSL. In addition, long chain AHLs antagonize the biosurfactant-mediated surface translocation of S. marcescens SS-1. Upstream of spnI there is a gene which we have termed spnT. spnI and spnT form an operon and although database searches failed to reveal any spnT homologues, overexpression of this novel gene negatively affected both sliding motility and prodigiosin production.

Deinococcus radiodurans is a robust bacterium best known for its capacity to resist to radiation. In this study, the SDS-PAGE coupled with high-precision LC-MS/MS was used to study the D. radiodurans proteome. A total of 1951 proteins were identified which covers 63.18% protein-coding genes. Comparison of the identified proteins to the key enzymes in amino acid biosyntheses from KEGG database showed the methionine biosynthesis module is incomplete while other amino acid biosynthesis modules are complete, which indicated methionine auxotrophy in D. radiodurans. The subsequent amino acid-auxotrophic screening has verified methionine instead of other amino acids is essential for the growth of D. radiodurans. With molecular evolutionary genetic analysis, we found the divergence in methionine biosynthesis during the evolution of the common ancestor of bacteria. We also found D. radiodurans lost the power of synthesizing methionine because of the missing metA and metX in two types of methionine biosyntheses. For the first time, this study used high-coverage proteome analysis to identify D. radiodurans amino acid auxotrophy, which provides the important reference for the development of quantitative proteomics analysis using stable isotope labeling in metabolomics of D. radiodurans and in-depth analysis of the molecular mechanism of radiation resistance.

Specific determination for IO3− and I− in ground water using high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) is described. Chromatographic separations were carried out using an ICS-A23 column. Iodine species were quantitatively eluted with 0.03 M ammonium carbonate. Under the Shield Torch high sensitive mode, the method detection limits for IO3− and I− with injection of 1 ml were 0.035 μg l−1 and 0.025 μg l−1, respectively. The method was applied to the determination of iodide and iodate in ground water. However, the signal response difference between iodate and iodide was observed by both the HPLC-ICP-MS system and the ICP-MS system. Also, the same signal response difference was also observed in other laboratories. It was reported that the signal response and stability of iodine species vary with their solution medium. The instability of IO3 – and I – was controlled by using KOH as their solution storing media. The IO3− and I− peak area ratios by HPLC-ICP-MS measurement were still close to 1:1 when the mixed standard solution was stored in the 0.01% KOH medium for 5 days.

This study investigates the feasibility of recombinant spider silk protein as a wound-dressing material for coverage of deep second-degree burn wounds using an animal model. Sixty Sprague-Dawley (SD) rats were randomly divided into four groups (15 rats in each group). Two types of recombinant spider silk proteins, pNSR-16 and pNSR-32, as well as collagen (as a control) were applied on the wound; the fourth group was left untreated as a negative control. Each group was evaluated on the 3rd, 5th, 7th, 14th and 21st days for wound-healing rate, histological test, levels of hydroxyproline synthesis and the samples were stained for immunohistochemical detection of the basic fibroblast growth factor (bFGF). The results of implantation testing showed that wound healing in the treatment groups--recombinant spider silk protein pNSR-16 and pNSR-32--was much better than that in the control group (p

This study intends to calculate the lifetime cancer risks resulting from intakes of trihalomethanes (THMs) in drinking water based on the presence of each THM species. The slope factors for each THM species are used, combined with exposure model and Monte Carlo simulations, to calculate the cancer risks with consideration of different exposure routes (oral ingestion, inhalation and dermal absorption). The results revealed that the highest risk comes from the inhalation exposure to chloroform during showers, which also dominates the total risk associated with chloroform exposure. For dichlorobromomethane and chlorodibromomethane, inhalation exposure also plays an important role for total risks; however, contribution from the oral consumption cannot be ignored for these two compounds. Bromoform contributes the least cancer risk among the four THM species, with a risk factor two orders of magnitude smaller than the other three THM species. For all of the four THM species, exposure from dermal absorption is not significant when compared with oral ingestion and inhalation exposures. This study also uses the THMs data collected from Taiwan to calculate the cancer risks associated with THM exposures in different areas of Taiwan. Due to the variations of the THMs compositions, it is observed that higher concentrations of total THMs do not necessarily lead to higher cancer risks. Areas with higher bromide concentration in raw water and often with higher total THM concentration may actually give lower cancer risk if the THMs formed shift to bromoform. However, this also leads to the violation of THM standards since bromoform has much higher molecular weight than chloroform. Based on the results of the cancer risks calculated from each THM species, the regulatory issue of the THMs was also discussed.

The title compouand {[Zn(C(4)H(4)O(6))(C(12)H(8)N(2))]·6H(2)O}(n), has a linear chain structure parallel to [100] with Zn(C(4)H(4)O(6))(C(12)H(8)N(2)) repeat units; the asymmetric unit consists of one Zn(2+) cation, one l-tartrate dianion, one 1,10-phenanthroline and six free water mol-ecules. The Zn atom is in a distorted octa-hedral ZnN(2)O(4) coordination environment. The crystal structure is stabilized by O-H⋯O hydrogen bonds and π-π stacking of the phenanthroline units [centroid-centroid distances in the range 3.552 (2)-3.625 (2)Å] occurs between the chains. The title compound is isotypic with the Cu and Mn analogues.

The title salt, (C(6)H(11)N(2))(2)[Cd(C(7)H(3)NO(4))(2)], displays a discrete mononuclear structure, in which the central Cd(II) atom is six-coordinated in a distorted octa-hedral coordination geometry by two N and four O atoms from two different pyridine-2,6-dicarboxyl-ate anions in an O(2),N,O(6)-tridentate chelation mode. The crystal packing is stabilized by N-H⋯O hydrogen bonds and π-π inter-actions [centroid-centroid distance = 3.576 (5) A].

In the title compound, [Mn(C(10)H(10)N(2))(6)](ClO(4))(2), the Mn(II) ion, located on an inversion center, is coordinated by six N atoms from three pairs of symmetry-related 1-benzyl-1H-imidazole ligands in a distorted octa-hedral geometry. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the complex cations and perchlorate anions.

The title compound, [Cu(2)(C(7)H(3)NO(4))(2)(C(12)H(12)N(6))(H(2)O)(2)]·H(2)O, displays a discrete dinuclear structure, in which the central Cu(II) atom is five-coordinated in a distorted square-based pyramidal coordination geometry and the flexible ligand 1,4-bis-(1,2,4-triazol-1-ylmeth-yl)benzene adopts a bis-monodentate bridging mode linking the Cu(II) atoms. It is further assembled by O-H⋯O hydrogen-bond inter-actions involving both the coordinated and uncoordinated water molecules. The latter exhibits half-occupancy.

In the title compound, C14H14N4, the center of the phenylene group is a crystallographic center of inversion. The compound is composed of three aromatic rings displaying a Z-like conformation. The dihedral angle between the pyrazole rings and the central phenyl ring is 83.84 (9)°.

With the growth of anaerobic digestion (AD) for biogas production, associated increasing digestate production may cause environmental problems if the increasing agricultural land required for digestate application is limited. An alternative is to valorise the digestate. Microwave assisted low-temperature hydrothermal treatment (MLHT; temperature 100 – 180 °C) was investigated as a post-treatment for AD of grass silage under two scenarios: 1) AD + MLHT and 2) Acid pre-treatment + AD + MLHT. Compared to the original grass silage, the digestates investigated required lower temperatures for carbonization in MLHT owing to their lower cellulose content. The higher MLHT temperatures (160 – 180 °C) led to significant increases in heating value and greater reductions in atomic ratios of O/C and H/C of hydrochar due to dehydration and decarboxylation reactions. As a result, higher temperatures contributed to higher sugar recovery, higher solid solubilization, and better quality of hydrochar. Under the MLHT at 180 °C, the hydrochar produced from digested grass silage in scenario 1 (AD + MLHT) exhibited a mass yield of 0.79 g/g total solid, a carbon content of 63.6% and an ash-free heating value of 27.6 kJ/g volatile solid; the biomethane potential from the process liquor was estimated as 68.7 ml CH4/g total solid. Scenario 1 is preferred over scenario 2 (acid pre-treatment + AD + MLHT) as it gave a higher yield and higher heating value of hydrochar. This study suggests that MLHT is a promising method to 1) produce hydrochar with an energy value comparable to lignite coal, and 2) recover additional biomethane through process liquor recycling.