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The objective of this work was to investigate the chemical compositions of the essential oil (EO) extracted from Senecio scandens by hydrodistillation and their insecticidal activities against Tribolium castaneum, Lasioderma serricorne and Liposceis bostrychophila. The chemical profile of the EO were analyzed by gas chromatography–mass spectrometry (GC-MS), and 20 compounds were identified which accounted for 88.03% of the total EO. Five major compounds identified in the EO were assayed against the three stored product insects. The EO showed strong contact toxicity to T. castaneum (LD50 = 18.01 μg/adult), L. serricorne (LD50 = 20.11 μg/adult) and L. bostrychophila (LD50 = 72.14 μg/cm2). Among all compounds, geraniol showed the contact toxicity against L. serricorne and L. bostrychophila with LD50 values of 15.82 μg/adult and 26.64 μg/cm2. The EO and its five chemical compounds also exhibited different level of potential repellence to the three stored product insects.

To screen the odorant binding proteins (OBPs) of Tribolium castaneum related to repellent activity and explore the repellent mechanism of terpenoids by studying the interaction between ligands and TcOBPs. Behavior tests indicated that (1R)-(+)-α-Pinene and β-Caryophyllene had repellent activity against T. castaneum. Through homology modeling and molecular docking, we screened TcOBP-9B, which is highly expressed in antennae and has strong interactions with (1R)-(+)-α-Pinene, β-Caryophylne, as target protein for recombinantly expressed. Fluorescence spectra and UV absorption spectra showed that TcOBP-9B had strong bind to (1R)-(+)-α-Pinene and β-Caryophyllene with concentration-dependent in static quenching. Thermodynamic date revealed that they formed stable complexes through van der Waals force, electrostatic and hydrophobic interactions. By fluorescence competitive binding assay, molecular docking and circular dichroism spectra, the binding sites of TcOBP-9B was confirmed as the α-helix, where the ligands were competitively bound to 1-NPN. These results suggested that TcOBP-9B was a significant target protein associated with repellent activity, providing new approach for screening repellents against T. castaneum.

This study was designed to investigate the insecticidal activity of the essential oils (EOs) and extracts from

The objective of this work was to investigate the chemical compositions of the essential oil (EO) extracted from

Background Mycobacterium chimaera infections subsequent to cardiac surgery are related to contaminated heater-cooler devices, with high mortality. Nevertheless, few studies have been reported in Asia. Case presentation We described the case of a 55-year-old man with Mycobacterium chimaera infection following cardiac surgery in the mainland of China. He was diagnosed with endocarditis caused by Mycobacterium chimaera subsequent to open heart surgery. Metagenomic next-generation sequencing (mNGS) and 16S rRNA gene PCR analysis were used to identify potential pathogens. The patient underwent redo valve replacement surgery and received combination therapy with azithromycin, ethambutol, linezolid, and amikacin. No signs of relapse were observed during the 11-month follow-up visit. Conclusions This is the first documented case of Mycobacterium chimaera infection following cardiac surgery in the mainland of China and the first documented transnational imported case worldwide. Moreover, mNGS is a novel diagnostic technology that can guide antimicrobial therapy prior to obtaining fluid/tissue culture results for Mycobacterium chimaera, providing a new approach for the detection of potential Mycobacterium chimaera infection.

This article shows that all novel exact solutions in the commented paper are not admitted by the original generalized Klein–Gordon equation and active-dissipative dispersive media equation. In addition, we present general solutions of certain auxiliary equation with sixth-degree nonlinear term. Then, based on above general solutions, we find that five cases in their Table 1 is shown to be incorrect.

Adsorption behavior of metal atom M (M = Cu, Ag, Au) on CeO2(100), a technologically important catalytic support surface, is studied by using first-principles density-functional theory calculations with the on-site Coulomb interaction taken into account (DFT + U). Prior to geometry optimization, small distortions in selected Ce–O distances are imposed to explore the energetics associated with reduction of Ce4+ to Ce3+ due to charge transfer to Ce during M adsorption. Results indicate that the adsorption is accompanied by an electron charge transfer between neutral metal atom and neighboring Ce4+ cation. For the same adsorption site, there exist multiple adsorption configurations with the excess electron localized at various nearest neighboring Ce ion relative to the M. The order on adsorption energies of M on CeO2(100) surface follows: Cu > Au > Ag. The atomic and electronic structures of M on CeO2(100) are compared with those of M on CeO2(111) and CeO2(110).

Many production peer-to-peer (P2P) streaming systems use content delivery networks (CDN) to protect the user’s quality of experiences. Thus, how to efficiently utilize the capacity of CDN (e.g., which peers receive services from the CDN nodes) is a problem of practical significance. Existing solutions adopt a passive, on-demand approach, which is inefficient in utilizing CDN resources. In this paper, we propose PROSE, a simple, novel scheme to achieve proactive, selective CDN participation for P2P streaming. PROSE introduces novel concepts such as choke point expansion nodes/super nodes and leads to efficient, light-weighted, and distributed algorithms to identify and serve these nodes using CDN. Our experimental results show that PROSE achieves at least 10%~25% performance improvement and 2~4 times overhead reduction compared with existing general CDN-P2P-hybrid schemes.

A multicomponent modification on the surface of porous nickel with nanoparticles is conducted by an electrophoretic deposition (EPD) technique to prepare new composite-based cathodes for molten carbonate fuel cells (MCFCs). Two new ternary composite-based cathodes, (nano- LiCoO2-LiFeO2 )- Ni and (nano- LiCoO2-CeO2 )- Ni , are inclined to possess good morphology and homogeneous element distribution when prepared under moderate current density resulting from a medium deposition voltage and suspension pH value in this work. Both composite-based cathodes manifest excellent anti-deformation and anti-dissolution performances under conditions of a simulated MCFC startup stage and are thus expected to be useful for application in the MCFC industry.

Atomic and electronic structures of LiFePO4 with the antisite defect and Mg doping at Li and Fe sites have been investigated using first-principles density-functional theory with the on-site Coulomb interaction taken into account. It is demonstrated that the most favorable antisite defect type is the exchange defect, in which Li and Fe ions exchange positions. The resultant longer Fe–O bond and narrower band gap drop a hint that the electronic and ionic transport properties may be improved. For the case of Mg doping, Mg is preferentially doped at the Fe site instead of the Li site to form a new LiFe1−yMgyPO4 solid solution, leading to a higher ionic conductivity. Moreover, the dependence of the electrochemical properties on the concentration of Mg dopant has also been discussed.

An active oxygen species in molten carbonate is the key to elucidate the complex mechanism of the cathode reaction in MCFC. However, under acidic condition of MCFC operation (P C O 2 > 1.01 x 10 4 Pa), the exact chemical state of the active oxygen species remains unclear and is a subject of continuous debates. In this work, we present the first experimental observation of peroxocarbonate/peroxodicarbonate species in acidic molten carbonate by using in-situ Raman spectroscopic technique. The results indicate that the predominant oxygen species (O 2 2-) in basic lithium-rich melts became unstable with the increase of acidity level in the melts and reacted with CO 2 to produce peroxocarbonate or peroxodicarbonate anion. In combination with the result of theoretical calculation, it is deduced that the peroxodicarbonate mechanism is the dominant feature in the cathode reaction path in MCFC.

The early deformation of the cathode material has been confirmed to be a significant factor in shortening the cell life. Thus, a new kind of cathode with both lower solubility and lighter deformation is highly desirable. In this work, a novel composite material, LiCoO2-Ni, was prepared by the electrophoretic deposition (EPD) technique, which, remarkably, is able to reduce the deformation and dissolution of cathode materials simultaneously. It was demonstrated to be very promising for the MCFC industry.

On the basis of previous work, the home-made deformation-testing system was further applied to detect the thickness change of porous nickel materials in the various experimental condition of molten carbonate. The deformation and dissolution behavior of porous nickel and the loading effect on the behavior were in situ studied in the process of oxidation and lithiation. The results indicated that both an obvious deformation and a severe nickel dissolution occurred during the oxidation/lithiation of porous nickel in molten carbonate under loading conditions. Furthermore, the dissolution of nickel from porous nickel was still significant even if without loading. It was found that the deformation of porous nickel closely corresponded to its dissolution during the oxidation/lithiation of porous nickel in molten carbonate.

A home-made LVDT displacement-measuring system was developed and applied to study the process of deformation on NiO during early stage of molten carbonate fuel cell (MCFC) operation. A series of in situ deformation tests was performed at a normal temperature (923 K) with porous Ni and NiO plaques under the atmospheres and load conditions in the presence of carbonate electrolyte. The results indicated that the most significant deformation took place when Ni plaque underwent both in situ oxidized and lithiated processes under a load condition, in particular, the deformation of Ni plaque occurred more severely at the beginning of processes.

Many concerns have been raised about the mechanism of cathode reaction in molten carbonate fuel cell (MCFC). The chemical behavior of oxide species at cathode in molten carbonate is a key for understanding the process of cathode reactions. In this paper, the variety and role of the oxide species in both bulk and thin-film of basic molten carbonates were investigated by using a novel in-situ Raman spectroscopy. The results indicated that the dominant oxide species under basic conditions was peroxide ion, and it was possible to transform into the oxygen of crystalline lattice during the lithium-doped process. It was demonstrated that in-situ Raman spectroscopic technique was a promising tool to elucidate the mechanism of electrode reaction in molecular level in the MCFC condition.

The paper focuses on location of seal imprints on Chinese bank-checks based on region growing. Region growing method can be applied to searching and locating connection region in an image. A seal imprint, however, is generally composed of various connection regions which are unconnected to each other. In order to locate the seal imprint, these connection regions must be fused together. In the paper, an algorithm for locating seal imprints on Chinese bankchecks based on region growing is proposed, of which a fusion criterion for connection regions in a seal imprint is put forth based on the image feature of Chinese bankcheck, and a center-rays model is proposed to find the topological relationship between connection regions, for which externally-tangent rectangle of region is used as the mark of location of region. The location experiment is achieved with a false-acceptance rate of 7.1% and a false-rejection rate of 0% on Chinese bankcheck.

Total paeony glycoside (TPG) is extracted and purified from a traditional Chinese herbal medicine. It has many biological and pharmacological activities. However, there are few dosage forms of TPG in the market because of its low bioavailability. Self-microemulsifying drug delivery system (SMEDDS) is a vital tool in solving low bioavailability of poor absorption drugs. So the objective of this study is to develop a new TPG-SMEDDS for the oral delivery of poorly soluble TPG. Through the construction of pseudo-ternary phase diagrams, the optimum prescription was obtained, which consisted of 18.70% TPG, 16.27% ethyl oleate as oil, 43.34% Cremophor RH40 as surfactant and 21.73% Transcutol P as cosurfactant. The characterizations of TPG-SMEDDS including morphological characterization, droplet size, zeta-potential, emulsification time, and dissolution study of TPG-SMEDDS were evaluated. The results showed that TPG-SMEDDS is stable and its release rate is high in four different media (0.1 mol x L(-1) HCl, pH 6.8 PBS, pH 7.4 PBS, and water). The relative bioavailability of SMEDDS was dramatically enhanced in an average of 1.52-fold that of TPG-suspension. It is concluded that the bioavailability of TPG is enhanced greatly by SMEDDS.

In the title coordination polymer, [Cu(NCS)(2)(C(12)H(8)N(2))](n), the Cu(II) atom is situated on a twofold rotation axis and is coordinated by two N atoms from the bidentate 1,10-phenanthroline ligand and four thio-cyanate groups to confer a CuN(4)S(2) octa-hedral geometry and resulting in a layer structure extending parallel to (100).

In the title coordination polymer, [Zn(C(8)H(4)O(4))(C(14)H(14)N(4))](n), the Zn(II) atom is coordinated by two N atoms from two 1,2-bis-(imidazol-1-ylmeth-yl)benzene ligands as well as by the two O atoms from two terephthalate ligands, confering a tetra-hedral coordination geometry. The bridging ligands generate a three-dimensional structure.

In the title coordination polymer, [Cu(NCS)2(C12H8N2)]n, the CuII atom is situated on a twofold rotation axis and is coordinated by two N atoms from the bidentate 1,10-phenanthroline ligand and four thio­cyanate groups to confer a CuN4S2 octa­hedral geometry and resulting in a layer structure extending parallel to (100).

In the title coordination polymer, [Zn(C8H4O4)(C14H14N4)]n, the ZnII atom is coordinated by two N atoms from two 1,2-bis­(imidazol-1-ylmeth­yl)benzene ligands as well as by the two O atoms from two terephthalate ligands, confering a tetra­hedral coordination geometry. The bridging ligands generate a three-dimensional structure.