Search

Improving the microphase separation structure of membranes is considered an effective strategy to solve the trade-off problem, which can increase the conductivity and reduce the swelling. This article designs poly(aryl alkylene) AEMs with different aryl backbone chains (biphenyl, p-terphenyl and m-terphenyl), with the goal of examining the effect of spatial structure main chains on the membrane performance. It is found that the membrane (m-QTPNP) has a better microphase separation structure and a conductivity of 143.5 mS cm−1 (80 °C) via SAXS, TEM and AFM. Due to the lower IEC (2.23 meq g−1), m-QTPNP has a good anti-swelling performance. During tensile testing, the elongation at break of m-QTPNP can reach 105.5% (wet state). Moreover, due to the obvious microphase separation, the attack of OH− on the quaternized groups is reduced, and m-QTPNP has a conductivity retention rate of 95.5% (80 °C, 2 M NaOH, 1560 h). In addition, the peak power density (PPD) of the H 2 /O 2 single cell equipped with m-QTPNP can reach 749 mW cm−2 (80 °C). After 90 h of durability testing, the voltage decayed to 92.2%, with a decay rate of 0.54 mV h−1. • The m-QTPNP AEM shows excellent mechanical properties with elongation at break up to 105.5% in wet state. • The m-QTPNP AEM exhibits an ionic conductivity of 143.5 mS cm−1 at 80 °C. • The peak power density of m-QTPNP in a H 2 /O 2 single cell is 749 mW cm−2. [ABSTRACT FROM AUTHOR]

Constructing chiral supramolecular assembly and exploring the underlying mechanism are of great significance in promoting the development of circularly polarized luminescence (CPL)‐active materials. Herein, we report a solvation‐mediated self‐assembly from single‐crystals to helical nanofibers based on the first protic acyclic (methoxy)(amino)carbenes (pAMACs) AuI‐enantiomers driven by a synergetic aurophilic interactions and H‐bonds. Their aggregation‐dependent thermally activated delayed fluorescence properties with high quantum yields (ΦFL) up to 95 % were proved to be attributed to packing modes of Au⋅⋅⋅Au dimers with π‐stacking or one‐dimensional extended Au⋅⋅⋅Au chains. Via drop‐casting method, supramolecular P‐ or M‐helices were prepared. Detailed studies on the helices demonstrate that formations of extended helical Au⋅⋅⋅Au molecular chains amplify supramolecular chirality, leading to strong CPL with high dissymmetry factor (|glum|=0.030, ΦFL=67 %) and high CPL brightness (BCPL) of 4.87×10−3. Our findings bring new insights into the fabrication of helical structures to improve CPL performance by modifying aurophilic interactions. [ABSTRACT FROM AUTHOR]

Constructing chiral supramolecular assembly and exploring the underlying mechanism are of great significance in promoting the development of circularly polarized luminescence (CPL)‐active materials. Herein, we report a solvation‐mediated self‐assembly from single‐crystals to helical nanofibers based on the first protic acyclic (methoxy)(amino)carbenes (pAMACs) AuI‐enantiomers driven by a synergetic aurophilic interactions and H‐bonds. Their aggregation‐dependent thermally activated delayed fluorescence properties with high quantum yields (ΦFL) up to 95 % were proved to be attributed to packing modes of Au⋅⋅⋅Au dimers with π‐stacking or one‐dimensional extended Au⋅⋅⋅Au chains. Via drop‐casting method, supramolecular P‐ or M‐helices were prepared. Detailed studies on the helices demonstrate that formations of extended helical Au⋅⋅⋅Au molecular chains amplify supramolecular chirality, leading to strong CPL with high dissymmetry factor (|glum|=0.030, ΦFL=67 %) and high CPL brightness (BCPL) of 4.87×10−3. Our findings bring new insights into the fabrication of helical structures to improve CPL performance by modifying aurophilic interactions. [ABSTRACT FROM AUTHOR]

The complex and efficient sex pheromone communication system in insects is essential for reproduction and for reproductive isolation of species. In moths, sex pheromone communication starts with male attraction to compounds emitted by females; only a few species act in the reverse. However, how the pheromones that are emitted by both sexes co‐regulate and coordinate mate finding and mating remains unknown. Here, we identified both the male and female pheromones of Eastern Grass Veneer moth, Agriphila aeneociliella (Lepidoptera: Crambidae), and demonstrated their efficiency in manipulating behavioral responses of the opposite sex. Combining data from analysis of gas chromatography‐electroantennogram detection, gas chromatography‐mass spectrometry, and olfactory behavior assays, the female pheromone of A. aeneociliella was identified as (Z,Z,Z)‐9,12,15‐octadecatrienal and (Z)‐9‐hexadecenyl acetate, while the male pheromone was determined to be 1‐nonanal. Both the 2 individual components of the female pheromone and their binary mixture were significantly attractive to males, and the 1‐nonanal male pheromone induced strong electrophysiological responses in females and induced attraction of females in a Y‐tube olfactory test. Depending on the concentration of 1‐nonanal, its addition to the binary mixture of the female pheromone either enhanced (10−3 or 10−2 μg/μL) or reduced (1 μg/μL) the aphrodisiac effect of the mixture on males. In wind‐tunnel bioassays, different concentrations of pheromones, including the binary mixture of female pheromone and the mixture of male and female pheromones, had significant effects on male behavior. Our findings suggested that the blend of both female and male pheromones plays a significant role in the sexual communication system in some moths. [ABSTRACT FROM AUTHOR]

It is an important research topic to construct microphase separation in anion exchange membranes (AEMs). The integration of rigid anthracene units into the main chains to form poly(anthracene- co - p -terphenyl piperidinium) AEMs is a new method by using π-π stacking to regulate microphase separation and construct ion transport channels in membranes. In this study, anthracene units were introduced for the first time to prepare AEMs with different anthracene contents. It is found that the introduction of rigid anthracene units into the backbone leads to an increase in the fractional free volume (FFV) of the membranes and a decrease in the ion conductive resistance. Moreover, the existence of long flexible di-piperidinium side chain helps to adjust the rigidity of the AEMs and enhances the mechanical properties of the membrane. The ionic conductivity of PA10TP-DMP is 153.8 mS cm−1 (80 °C). In the meanwhile, the conductivity retention of 91.7 % was observed after the alkaline resistance test (80 °C, 2 M NaOH) for 1200 h. In addition, the PA10TP-DMP based H 2 –O 2 single cell has a peak power density of 840.3 mW cm−2 and a high durability after 100 h test. [Display omitted] • Poly(anthracene- co - p -terphenyl piperidinium) AEMs were prepared by introducing anthracene units. • The presence of rigid anthracene units increases the free volume and π-π stacking in the membrane. • The introduction of anthracene segment promotes microphase separation to obtain high conductivity. • The highest power density reaches up to 840.3 mW cm−2 in H 2 –O 2. [ABSTRACT FROM AUTHOR]

Anion exchange membranes (AEMs) are one of the most critical materials determining the fuel cell (FC) performance. From current reports, there are still many limit factors for AEMs, such as conductivity, mechanical performance, power density and durability, which greatly affect their practicality. Here, we introduce a range of arylfluoroketone monomers with different side chain lengths into the poly (aryl-alkylene) matrix material using a copolymerization strategy to get AEMs. This study aims to investigate the effect of side chain length on the performance of AEMs, such as phase separation, ion conductivity and mechanical properties. Due to the existence of long alkyl side chains, QTPNPC4 shows significant hydrophilic aggregation, outstanding OH− conductivity (158.6 mS cm−1, 80 °C) and excellent flexibility (109.1 %). Meanwhile, QTPNPC4 exhibits remarkable ex-situ durability (96.3 %) and chemical stability (96.6 %) after soaking in a 2 M NaOH solution for 1560 h at 80 °C. In addition, the peak power density (PPD) of a single cell with QTPNPC4 reaches 927 mW cm−2 (80 °C), and the membrane has good in-situ durability (0.689 mV h−1). [Display omitted] • QTPNPC4 shows the elongation at break up to 109.1 % in wet state. • QTPNPC4 exhibits a highest ion conductivity of 158.6 mS cm−1 at 80 °C. • The peak power density of a QTPNPC4-based single cell is 927 mW cm−2. [ABSTRACT FROM AUTHOR]

An open tetra-imidazolium salt (2) based on tetramethylenebenzene was synthesized and characterized, and its structure was determined by X-ray diffraction. Compound 2 possesses four arms with an inverse symmetric center. Additionally, the recognition of anions by 2 was investigated via fluorescence spectra, UV/Vis spectra, 1H NMR, HRMS and IR spectra. The experimental results showed that 2 can effectively distinguish H 2 PO 4 − from other anions. An open tetra-imidazolium salt was synthesized and characterized, and its selective recognition to H 2 PO 4 − was studied. [Display omitted] • An open tetra-imidazolium salt 2 was synthesized, and its structure was determined by X-ray diffraction. • Compound 2 had high sensitivity and selectivity and great affinity for H 2 PO 4 −. • The big association constant (8.2 × 104 M−1) indicated that compound 2 can firmly hold H 2 PO 4 −. • The low detection limit (1.47 × 10−7 mol/L) showed that compound 2 has high sensitivity for H 2 PO 4 −. [ABSTRACT FROM AUTHOR]

Anion exchange membranes (AEMs) are the core component of anion exchange membrane fuel cells (AEMFCs), among which poly(aryl piperidinium) (PAP) based AEMs have been studied. Herein, we report some scalable di-piperidinium cationic crosslinkers to enhance the mechanical properties, ionic conductivity and alkaline stability of PAP-based AEMs. The results show that the morphology of AEMs can be affected by adjusting the length of crosslinker. PTP-DPC/C6-50% shows a high OH− conductivity (80 °C, 131.2 mS cm−1) due to its microphase separation. It also has excellent elongation at break (20.8%) and tensile strength (36.5 MPa). The peak power density of the PTP-DPC/C6-50% based cell can reach 616.2 mW cm−2 under H 2 –O 2 conditions. The crosslinked network formed by long alkyl spacer chains is helpful to improve the alkaline stability of the AEM. After alkaline stability test, the conductivity of the PTP-DPC/C10-50% membrane maintained at 92.2%. [Display omitted] • Di-piperidine crosslinkers of different lengths are used in crosslinked membranes. • PTP-DPC/C6-50% has an obvious microphase separation morphology. • High conductivity and excellent alkaline stability can be obtained. • The highest power density is 616.2 mW cm−2 in a H 2 –O 2 single cell. [ABSTRACT FROM AUTHOR]

[Display omitted] Anion exchange membrane fuel cells (AEMFCs), which are more economical than proton exchange membrane fuel cells (PEMFCs), stand out in the context of the rapid development of renewable energy. Superacid-catalyzed ether-free aromatic polymers have recently received a lot of attention due to their exceptional performance, but their development has been hampered by the trade-off between the dimensional stability and ionic conductivity of anion exchange membranes (AEMs). Here, we introduced fluoroketones containing different numbers of fluorinated groups (x = 0, 3 and 6) in the main chain of p-terphenyl piperidine because of the favorable hydrophobic properties of fluorinated groups. The results show that fluorinated AEMs can enhance OH− conductivity by building more aggregated hydrophilic channels while ensuring dimensional stability. The PTF6-QAPTP AEM with more fluorinated groups has the most excellent performance at 80 °C with an OH− conductivity of 142.7 mS cm−1 and a swelling ratio (SR) of only 4.55 %. Additionally, it exhibits good alkali durability, with the OH− conductivity and quaternary ammonium (QA) cation retaining at 93.45% and 92.6%, respectively, after immersion in a 2 M NaOH solution at 80 °C for 1200 h. In addition, the power density of the PTF6-QAPTP based single cell reaches 849 mW cm−2 when the current density is 1600 mA cm−2. The PTF6-QAPTP based cell has a voltage retention of 88% after 80 h of stability testing at a constant current density of 300 mA cm−2 at 80 °C. [ABSTRACT FROM AUTHOR]

The simplification of data processing is the frontier domain for electronic nose (e-nose) applications, whereas there are a lot of manual operations in a traditional processing procedure. To solve this problem, we propose a novel data processing method using the bio-inspired neural network modeled on the mammalian olfactory system. Through a neural coding scheme with multiple squared cosine receptive fields, continuous sensor data are simplified as the spike pattern in virtual receptor units. The biologically plausible olfactory bulb, which mimics the structure and function of main olfactory pathways, is designed to refine the olfactory information embedded in the encoded spikes. As a simplified presentation of cortical function, the bionic olfactory cortex is established to further analyze olfactory bulb's outputs and perform classification. The proposed method can automatically learn features without tedious steps such as denoising, feature extraction and reduction, which significantly simplifies the processing procedure for e-noses. To validate algorithm performance, comparison studies were performed for seven kinds of Chinese liquors using the proposed method and traditional data processing methods. The experimental results show that squared cosine receptive fields and the olfactory bulb model are crucial for improving classification performance, and the proposed method has higher classification rates than traditional methods when the sensor quantity and type are changed. [ABSTRACT FROM AUTHOR]

Macrocyclic tetra-imidazolium salt 2 was synthesized and characterized, and its crystal structure was determined by X-ray diffraction. One 30-membered macrocycle of 2 was constructed by four imidazoliums, two carbazoles and two proplenes. The recognition of 2 to aromatic compounds was studied via fluorescence spectra, UV/vis spectra, HRMS, 1H NMR and IR spectra. The results showed that 2 had high selectivity and sensitivity to p -nitroaniline (p -NA). A macrocyclic tetra-imidazolium salt was prepared and characterized, and it was an effective chemosensor for p-nitroaniline. [Display omitted] • Macrocyclic tetra-imidazolium salt 2 was synthesized, and its crystal structure was determined by X-ray diffraction. • Compound 2 had high sensitivity and selectivity and great affinity for p -nitroaniline.. • The big association constant (8.2 × 104 M−1) indicated that compound 2 can firmly hold p -nitroaniline. • The low detection limit (7.3 × 10−8 mol/L) showed that compound 2 has high sensitivity for p -nitroaniline. [ABSTRACT FROM AUTHOR]

The English grain aphid, Sitobion avenae, is a major pest species of wheat crops; however, certain varieties may have stronger resistance to infestation than others. Here, we investigated 3 classical resistance mechanisms (antixenosis, antibiosis, and tolerance) by 14 wheat varieties/lines to S. avenae under laboratory and field conditions. Under laboratory conditions, alatae given the choice between 2 wheat varieties, strongly discriminated against certain varieties. Specifically, the ‘Amigo’ variety had the lowest palatability to S. avenae alatae of all varieties. ‘Tm’ (Triticum monococcum), ‘Astron,’ ‘Xanthus,’ ‘Ww2730,’ and ‘Batis’ varieties also had lower palatability than other varieties. Thus, these accessions may use antibiosis as the resistant mechanism. In contrast, under field conditions, there were no significant differences in the number of alatae detected on the 14 wheat varieties. One synthetic line (98-10-30, a cross between of Triticum aestivum (var. Chris) and Triticum turgidum (var. durum) hybridization) had low aphid numbers but high yield loss, indicating that it has high antibiosis, but poor tolerance. In comparison, ‘Amigo,’ ‘Xiaoyan22,’ and some ‘186Tm’ samples had high aphid numbers but low yield loss rates, indicating they have low antibiosis, but good tolerance. Aphid population size and wheat yield loss rates greatly varied in different fields and years for ‘98-10-35,’ ‘Xiaoyan22,’ ‘Tp,’ ‘Tam200,’ ‘PI high,’ and other ‘186Tm’ samples, which were hybrid offspring of T. aestivum and wheat related species. Thus, these germplasm should be considered for use in future studies. Overall, S. avenae is best adapted to ‘Xinong1376,’ because it was the most palatable variety, with the greatest yield loss rates of all 14 wheat varieties. However, individual varieties/lines influenced aphid populations differently in different years. Therefore, we strongly recommend a combination of laboratory and long-term field experiments in targeted planting regions to identify varieties/lines that consistently show high resistance to S. avenae infestation. [ABSTRACT FROM AUTHOR]

A new bis-benzimidazolium salt, 1,3-bis{[ N - (8′-hydroxy-9′,10′-anthraquinon-1′-oxyethyl)benzimidazoliumyl]methylene}mesitylene hexafluorophosphate (1) was synthesized and characterized. The selective recognition of compound 1 to aromatic compounds was investigated through fluorescence, 1H NMR titrations, HRMS and IR spectra. The experimental results indicated that 1 can distinguish effectively p -nitroaniline (p -NA) from other aromatic compounds. A new chemodosimeter based on bis-benzimidazolium salt was prepared, and its recognition performance for p-NA was investigated. [Display omitted] • A new bis-benzimidazolium salt based mesitylene 1 was synthesized and characterized. • The selective recognition of 1 to aromatic compounds was investigated. • Compound 1 had high sensitivity for p -nitroaniline, and the detection limit was 8.51 × 10−8 mol/L. • The association constant was 4.5 × 104 M−1 for 1 · p -NA, which indicated that host can firmly hold guest. [ABSTRACT FROM AUTHOR]

[Display omitted] • Provide approaches to synthesize fluorous polyproline peptides. • Systematic analysis for the impact of fluorous groups on peptide helix. • Reveal fundamental intramolecular fluorous interactions within a peptide helix. • Provide suitable design for solvent-responsive fluorous peptide helices. The unique interaction between fluorine atoms has been exploited to alter protein structures and to develop synthetic and analytical applications. To expand such fluorous interaction for novel applications, polyproline peptides represent an excellent molecular nanoscaffold for controlling the presentation of perfluoroalkyl groups on their unique secondary structure. We develop approaches to synthesis fluorinated peptides to systematically investigate how the number, location and types of the fluorous groups on polyproline affect the conformation by monitoring the transition between the two major polyproline structures PPI and PPII. This work provides valuable information on how fluorous interaction affects the peptide structure and also benefits the design of functional fluorous molecules. [ABSTRACT FROM AUTHOR]

Variables in the production environment inevitably result in deviations from the generated schedules. These variables affecting the system performance should be considered when dealing with dynamic dispatching problems. In addition, determination of the dispatching rules based on a single performance criterion cannot satisfy the requirements of different production performances. In this research, a dynamic dispatching strategy for multiple performance measures based on fuzzy inference is proposed. First, the variables affecting the system performance are identified. Then, the fuzzy membership functions and the fuzzy inference rules are established based on the simulation data. According to the statuses of environment variables, the fuzzy inference is performed to find an appropriate dispatching rule at each decision point to meet the best multiple performance measures. An example of the application is presented. The simulation results indicate that the proposed fuzzy-based dynamic dispatching strategy has a very good and robust performance. [ABSTRACT FROM AUTHOR]

Abstract: There is conflicting evidence regarding the role of nitric oxide (NO) in the process of resistance against blood-stage malaria parasites. In this study, we used two strains of mice infected with Plasmodium yoelii 17XL in order to assess the NO production profile and its possible role during the early stage of malaria infection. We found a greater elevation of NO production associated with a sharp increase in the levels of IFN-γ in infected DBA/2 mice, compared with infected BALB/c mice. This difference was associated with relatively lower parasitemia, a higher constituent ratio of infected reticulocytes, and greater survival in DBA/2 mice. Endogenous IFN-γ driving Th1 immunity was responsible for NO production. Moreover, schizonts treated in vitro with NO donors caused a delayed infection to BALB/c mice in a dose and time-dependent manner. These data, thus, suggest that NO may play an inhibitory role in Plasmodium infection. [Copyright &y& Elsevier]

Two tetra-benzimidazolium salts with bridging 9,10-anthraquinone (1 and 2) were synthesized. The crystal structure of 1 was determined by X-ray analysis. One 38-membered macrocycle in 1 was formed by two 9,10-anthraquinone, four benzimidazoliums and six alkylene groups, in which π···π interactions between two anthraquinone were observed. By contrast, compound 2 adopted an open structure, and it was formed by one 9,10-anthraquinone and four benzimidazolium groups, four alkylene groups and two propyl groups. Additionally, the recognition of anions was investigated using 1 (or 2) as chemosensors via fluorescence spectra, UV/vis spectra, HRMS, 1H NMR and IR spectra. The results indicated that compound 1 can distinguish H 2 PO 4 − from other anions by the naked eyes (from colorless to yellow under visible light) or by instruments, and compound 2 was able to differentiate H 2 PO 4 − from other anions by instruments. [Display omitted] • Tetra-benzimidazolium salts 1 and 2 were synthesized, and the crystal structure of 1 was determined. • Compounds 1 and 2 had high sensitivity and selectivity and great affinity for H 2 PO 4 −. • The big association constants indicated that hosts can firmly hold guests to form stable 1. H 2 PO 4 - and 2 ·H 2 PO 4 -. • The detection limits of 1 ·H 2 PO 4 - and 2 ·H 2 PO 4 - locate in the middle of reported values. • Macrocycle 1 can detect H 2 PO 4 - not only by instrument, but also by the naked eyes. [ABSTRACT FROM AUTHOR]

A two-dimensional Green's function suitable for a coated isotropic thermoelastic semi-infinite plane with a line heat source above the surface has been obtained using the method of images. Firstly, based on the control equations of the isotropic thermoelastic materials and the two-dimensional heat conduction equations, the general solutions to three harmonic functions have been obtained. Secondly, six potential function equations have been acquired using the method of images. Finally, three equations that are expressed by three harmonic functions have been obtained by substituting six series of harmonic functions into the boundary conditions of the coated surface. In this way, nine recursive equations have been determined. By taking Green's function of the isotropic semi-infinite thermoelastic plane with a line heat source above the surface as the first term, the thermoelastic coupling field for the coated semi-infinite plane has been calculated using the recursive formula. The interface temperature increment component and the interface stress components of the coating structures have been calculated numerically. By analyzing the thermal stress of different coated materials, valuable conclusions such as the interface effect, tensile failure, and shear delamination have been obtained, which can provide a reliable basis for the design and analysis of thermal barrier coating structures. [ABSTRACT FROM AUTHOR]

Thermally induced stress is an important scientific problem in engineering applications. In this paper, an accurate and efficient method for the two-dimensional quasi-static thermal elastic problem is established to explore the thermal stress problem. First, the compact quasi-static two-dimensional general solution is derived in terms of simple potential functions. The general solution is simple in form and can be derived for arbitrary boundary problems subjected to a line heat load. This is completely new to the literature. Second, Green's function solutions of an infinite plane under the line pulse heat source based on the general solutions are presented to analyze the thermal stress field. Lastly, numerical results are taken into account to study the temperature and stress field induced by the dynamic heat source load. The corresponding analysis can constitute to reveal the mechanism of thermal elastic problems and provide some guidance for experiments or engineering structural design in the future work. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of crown ether cavity size on the performance of AEMs is investigated. • The QAPCE-18-6 AEM exhibits a highest ionic conductivity of 122.5 mS cm−1 at 80 °C. • The peak power density of QAPCE-18-6 in a H 2 /O 2 single cell is 562 mW cm−2. Anion exchange membrane fuel cells (AEMFCs) have emerged as a promising alternative to proton exchange membrane fuel cells (PEMFCs) due to their adaptability to low-cost stack components and non-noble-metals catalysts. However, the poor alkaline resistance and low OH− conductivity of anion exchange membranes (AEMs) have impeded the large-scale implementation of AEMFCs. Herein, the preparation of a new type of AEMs with crown ether macrocycles in their main chains via a one-pot superacid catalyzed reaction was reported. The study aimed to examine the influence of crown ether cavity size on the phase separation structure, ionic conductivity and alkali resistance of anion exchange membranes. Attributed to the self-assembly of crown ethers, the poly (crown ether) (PCE) AEMs with dibenzo-18-crown-6-ether (QAPCE-18-6) exhibit an obvious phase separated structure and a maximum OH− conductivity of 122.5 mS cm−1 at 80 °C (ionic exchange capacity is 1.51 meq g−1). QAPCE-18-6 shows a good alkali resistance with the OH− conductivity retention of 94.5% albeit being treated in a harsh alkali condition. Moreover, the hydrogen/oxygen single cell equipped with QAPCE-18-6 can achieve a peak power density (PPD) of 574 mW cm−2 at a current density of 1.39 A cm−2. [ABSTRACT FROM AUTHOR]

Four new dinuclear lanthanide compounds, [Ln(hfac) 2 L] 2 (Ln(III) = Eu ( 1 ) and Tb ( 2 )) and [Ln(tfac) 2 L] 2 ·(C 7 H 16 ) x (Ln(III) = Tb ( 3 ), Yb ( 4 ), HL = 2-[[(4-iodophenyl)imino]methyl]-8-hydroxyquinoline, hfac = hexafluoroacetylacetonate, tfac = trifluoroacetylacetonate), have been synthesized, structurally and magnetically characterized. The X-ray structural analysis exhibit that 1 – 4 are phenoxo-O-bridged dinuclear compounds and central Ln(III) ions are eight-coordinated with two bidentate hfac − and two μ 2 -O bridging 8-hydroxyquinoline Schiff base ligands. Magnetic measurements indicated that slow magnetic relaxation behaviors were observed in 2 under 0 dc field, with an optimized dc field of 2000 Oe for 2 , the quantum tunneling of the magnetization was suppressed with Δ E / k B of 6.72 K. However, no evident ac magnetic signals were observed in 3 under 0 dc field. The distinct single-molecule magnets behaviors are mainly due to the slight different coordination environments around central Tb III ions of 2 and 3 . [ABSTRACT FROM AUTHOR]

Aphids cause serious damages to crops not only by tacking sap but also by transmitting numerous viruses. To develop biological control, the aphid alarm pheromone, namely E-β-farnesene (EβF), has been demonstrated to be efficient to repel aphids and as attract beneficials, making it a potential tool to control aphid pests. Considering aphids also as virus vectors, changes of their behavior could also interfere with the virus acquisition and transmission process. Here, a combination of two aphid species and two potato virus models were selected to test the influence of EβF release on aphid and virus dispersion under laboratory conditions. EβF release was found to significantly decrease the population of Myzus persicae and Macrosiphum euphorbiae around the infochemical releaser but simultaneously also increasing the dispersal of Potato Virus Y (PVY). At the opposite, no significant difference for Potato Leaf Roll Virus (PLRV) transmission efficiency was observed with similar aphid alarm pheromone releases for none of the aphid species. These results provide some support to carefully consider infochemical releasers not only for push–pull strategy and pest control but also to include viral disease in a the plant protection to aphids as they are also efficient virus vectors. Impact of aphid kinds and transmission mechanisms will be discussed according to the large variation found between persistent and non persistent potato viruses and interactions with aphids and related infochemicals. [ABSTRACT FROM AUTHOR]

Phytopathogenic fungi such as Rhizoctonia solani and Sclerotinia sclerotiorum caused multiple plant diseases resulting in severe loss of crop production. Increasing documents endorsed that endophytes are a striking resource pool for numerous metabolites with various bioactivities such as anti-fungal. Here we reported the characterization and anti-phytopathogenic activity of sporothriolide, a metabolite produced by Nodulisporium sp. A21—an endophytic fungus in the leaves of Ginkgo biloba . Among the total twenty-five endophytic fungi isolated from the healthy leaves of G. biloba , the fermentation broth (FB) of the strain A21 was found potently inhibitory activity against R. solani and S. sclerotiorum using mycelia growth inhibition method. A21 was then identified as Nodulisporium sp., the asexual stage of Hypoxylon sp., by microscopic examination and ITS rDNA sequence data comparison. Under the bioassay-guided fractionation, sporothriolide was isolated from the petroleum ether extract of the FB of A21, whose structure was established by integrated interpretation of HR-ESI-MS and 1 H- and 13 C-NMR. Furthermore, the crystal structure of sporothriolide was first reported. In addition, sporothriolide was validated to be potently antifungal against R. solani , S. sclerotiorum and inhibit conidium germination of Magnaporthe oryzae in vitro and in vivo, indicating that it could be used as a lead compound for new fungicide development. [ABSTRACT FROM AUTHOR]

Abstract: The effect of antimalarial drugs on immune responses to the malaria infection is evaluated in vivo using two experimental self-cured rodent models. BALB/c and DBA/2 mice were infected by Plasmodium yoelii 17XNL and 17XL strains, respectively, and then treated with different doses of antimalarial drugs: chloroquine (228mg/kg or 114mg/kg of the body weight) or artesunate (78mg/kg or 39mg/kg). The effect of antimalarial drugs on host immune responses was evaluated by parasitemia, splenocyte IFN-γ production level, and parasite-specific IgG level in the serum, however, no significant differences were observed between drug-treated and untreated groups. Moreover, most of the infected mice of all groups showed the ability to resist homologous reinfection (challenged on day 60 post-infection), only a few mice experienced transient, low parasitemia. The rechallenged mice were accompanied by high level of parasite-specific IgG. Therefore, this research implicated that, for BALB/c and DBA/2 mice, chloroquine or artesunate treatment of blood-stage P. yoelii infections does not compromise acquired immunity to malaria in either primary infection or upon rechallenge. [Copyright &y& Elsevier]

Three-dimensional numerical simulations of transient thermal convection in a shallow molten silicon pool with Czochralski configuration (depth d = 3 mm) have been conducted to understand the transition mechanism of the flow patterns on silicon melt in Czochralski furnaces. The crucible side wall is maintained at constant temperature. Bottom and free surfaces are either adiabatic or allow heat transfer in the vertical direction. The simulation results indicate that two flow transitions occur when the radial temperature difference along the free surface increases. First, the steady two-dimensional flow becomes steady three-dimensional flow, and then it evolves to three-dimensional oscillatory flow when the temperature difference is further increased. This oscillatory flow is characterized by spoke patterns traveling in either the clockwise or counterclockwise direction. It is observed that a transition hysteresis exists from oscillatory three-dimensional flow to steady three-dimensional flow when the radial temperature difference decreases. The critical conditions for the flow pattern transition are determined. Characteristics of the bifurcation and hysteresis of flow pattern transition are discussed. [ABSTRACT FROM AUTHOR]

C12H16CuF6PN8, monoclinic, C2/c (no. 15), a = 13.102(2) Å, b = 9.7902(18) Å, c = 14.727(3) Å, β = 102.336(6)°, V = 1845.3(6) Å3, Z = 4, Rgt(F) = 0.0291, wRref(F2) = 0.0733, T = 150(2) K. [ABSTRACT FROM AUTHOR]

Patients undergoing hemodialysis (HD) are particularly vulnerable to coronavirus disease 2019 (COVID-19) and are at increased risk of developing severe infection. However, given the exclusion of such patients from clinical trials, there are limited data regarding the effectiveness of the antiviral drug nirmatrelvir/ritonavir (N/R) in patients on HD. We prescribed N/R to 4 patients on HD with COVID-19 after obtaining informed consent. Their clinical symptoms were improved at approximately 3 days after N/R administration. The viral load was reduced after approximately 10 days. The main adverse effects were nausea and vomiting. Rational dosage adjustment obtained good tolerance but did not influence the efficacy. These results suggest that N/R may be a promising agent for patients on HD with COVID-19. [ABSTRACT FROM AUTHOR]

Increasing studies suggest that insecticides are one of the plant stress elements that affect plant growth and productivity by interfering with cell metabolic and biochemical activities. Here, we show that the application of commonly used pesticides omethoate and cypermethrin on maize (Zea maysL. cv. Luyu 9) seedling leaves resulted in adverse effects on leaf ultrastructure changes under laboratory conditions. Electron microscopic studies reveal that the topical application of organophosphorus insecticide omethoate causes direct injury of leaf ultrastructures including cell wall breakdown of abaxial epidermis cells, inner cells, stomata guard cells; degradation of mitochondrial membrane, and chloroplast envelope membrane; and abnormal changes of lamella arrangement of chloroplast. And the topical application of cypermethrin insecticide causes plasmolysis of cells of the adaxial epidermis, mitochondrial cristae are degraded, and loosen arranged lamella of amyloplasts. All these changes indicated that omethoate and cypermethrin are stress factors that caused adverse effects on plant ultrastructures and biochemical molecules. [ABSTRACT FROM AUTHOR]

Background: Fatigue damage of the long bones is prevalent in running athletes and military recruits due to vigorous mid- and long-term physical activity. The current study attempted to know the features of bony athletic fatigue damage and to explore the mechanism of fatigue damage repair through bone targeted remodeling process.Methods: Right ulnae of the Wistar rats were fatigue loaded on an INSTRON 5865 to construct the athletic fatigue damage model, and several time points (i.e. experimental days: 0, 7, 13 and 19) were selected to simulate physiological status, preliminary, mid-term and perennial stage during continuous high-intensive training, respectively. The multi-level responses of rat ulnae under the athletic fatigue loading, including cellular protein expression, micro damage or micro-crack and macro mechanical properties, were tested and statistically analyzed.Results: Wistar rats, subjected to the athletic fatigue loading protocol, experienced a decrease of ulna fatigue mechanical properties and an active bone resorption of the loaded ulnae in the early stage, whereafter, a hyperactive bone formation and significant improvements of ulnae fatigue mechanical properties were detected. However, a deterioration of quasi-static mechanical properties in the subsequent period implied limitations of bone remodeling to maintain the bearing capacity of bone during long-term strenuous exercise.Conclusions: In summary, after athletic fatigue loading, bone targeted remodeling is activated and proceeds to repair fatigue damage, but only to a certain extent. [ABSTRACT FROM AUTHOR]

Context: Patrinia villosa(Thunb.) Juss (Valerianaceae) is an important ancient herbal medicine widely used for inflammation, wound healing, and abdominal pain. But little is known of the phytochemical constituents of this herbal plant. Objective: The objective of this study is to isolate and identify the bioactive components fromP. villosa. Materials and methods: A 70% EtOH extract ofP. villosawas subjected to normal-phase silica, ODS silica gel column chromatography, and semi-preparative HPLC chromatography after partitioned successively with light petroleum, dichloromethane andn-BuOH. Chemical structures of the compounds were elucidated by spectroscopic methods including UV, 1D-NMR, 2D-NMR, HR-ESI-MS, and CD spectra. The cytotoxic activity of the new component was determined with the SMMC-7721 cell line using the MTT method after incubation for 48 h. Results: A new flavonoid named patriniaflavanone A (1) along with four known compounds was isolated fromP. villosa. The four known compounds were identified as luteolin 7-O-glucuronide-6″-methyl ester (2),p-hydroxyphenylacetic acid methyl ester (3),trans-caffeic acid (4), andtrans-caffeic acid methylate (5) by comparison of their spectral data with the reported data. The IC50value of patriniaflavanone A (1) on SMMC-7721 was 61.27 μM. Discussion and conclusion: This is the first report on the isolation and identification of patriniaflavanone A (1), and compounds2–5were isolated for the first time from the title plant. Patriniaflavanone A (1) exhibited moderate cytotoxic activity. [ABSTRACT FROM AUTHOR]

In this paper, we present the design of a portable odor-tracing instrument and propose a new method for odor tracing using the instrument. The odor-tracing instrument comprises three gas sensors, a microprocessor, and a liquid crystal display. The gas sensors are placed in a regular triangle. When odor molecules reach the surface of a gas sensor, the output of the sensor changes. To obtain more features from the sensor outputs, we use a scale-space method to obtain multitime-scale information. A time series for the sensor data can then be calculated by feature-point matching. The direction of the odor source can be estimated using a graphical statistical method. The method uses relative output information from the sensors to eliminate the influence of sensor drift. Indoor and outdoor experiments showed that the instrument could indicate the odor source precisely in a windy environment. According to the guidance of the system, users can locate an odor source precisely. [ABSTRACT FROM PUBLISHER]

Abstract: Aphids cause much damage to Chinese cabbage in northern China. Over reliance on pesticides have large environmental and human health costs that compel researchers to seek alternative management tactics for aphid control. The component of aphid alarm pheromone, E-β-Farnesene (EβF), extracted from Matricaria chamomilla L., which attracts natural enemies in the laboratory, may have significant implications for the design of cabbage aphid control strategies. The purpose of this paper is to understand the effects of EβF on natural enemies to cabbage aphid control in Chinese cabbage fields. Ladybeetles on Chinese cabbage leaves in EβF released plots and Aphidiidae in EβF released yellow traps were significantly higher than those of in controls. No significant differences were detected in the interactions of different treatments and the two years for all natural enemies. More important, lower aphid densities were found in EβF released plots. Our results suggested that the EβF extracted from M. chamomilla L. could attract natural enemies to reduce cabbage aphids in the Chinese cabbage fields. [Copyright &y& Elsevier]