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The electronic structures and open-shell diradical character of organic diradicaloids endow them with potentially useful optical, electronic and magnetic properties. Here, an open-shell nitrogen-centered diradicaloid is reported and shown to readily react with Lewis and Brønsted acids to form acid-base adducts, allowing for tuning of ground-state electronic structure, diradical character and spin density distribution.

AIM: To investigate the protective effect and mechanism of luteolin on H2O2-induced oxidative damage of retinal pigment epithelium(RPE)cells. METHODS:ARPE-19 cells were divided into the control group, H2O2 group, different doses of luteolin groups and Nrf2 inhibitor group, and the oxidative damage model of RPE was prepared by 100μmol/L H2O2, except for the control group. Cell activity was detected by Methyl thiazolyl tetrazolium(MTT)assay and proper experimental concentration of luteolin was determined. The cell morphology and activity was observed in each group. Cell apoptosis rate and reactive oxygen species(ROS)were detected by flow cytometry, malondialdehyde(MDA)and superoxide dismutase(SOD)were detected by kit method, and the expression of caspase-3, poly adeno-sine diphosphate ribose polymerase(PARP), B cell lymphoma-2(Bcl-2), nuclear factor erythroid 2-related factor 2(Nrf2)and heme oxygenase-1(HO-1)proteins were detected by Western blot. RESULTS: 100μmol/L luteolin has toxic effects on ARPE-19 cells, so 25μmol/L and 50μmol/L luteolin were selected for subsequent experiments. The cell activity, SOD activity and the protein expression levels of Bcl-2, Nrf2, HO-1 in 25μmol/L and 50μmol/L luteolin groups were significantly higher than the H2O2 group(P

The design of covalent macrocycles which show characteristic self-assembly behaviour and host-guest properties is challenging. Here, the authors demonstrate the synthesis of diphenylamine[n]arenes through a one-pot synthesis and demonstrate the π-π pi stacking of the non-planar rings as well as ethane/ethyne host-guest interactions.

It is well known that large-sized nonmetallic inclusion seriously affects the mechanical properties of high-strength steels, particularly the fatigue properties. Therefore, significant efforts have been made to enhance the fatigue properties of gear steels by improving the cleanliness and, thus, reducing the size and the number of inclusions in steels. However, an effective inclusion inspection method is particularly important because of the relatively low-rate emergence of large-sized inclusions in highly clean steels. Herein, a new inclusion inspection strategy was proposed using a properly hydrogen-charged tensile specimen combined with the application of the statistics of extreme value (SEV) method, which can be used to conveniently and reliably estimate the maximum inclusion size in any volume of high-strength steel and its fatigue strength. A commercial heat of 20Cr2Ni4A gear steel with high cleanliness was used to verify the proposed method. Standard tensile specimens were quenched, tempered at low-temperature, and then properly charged with electrochemical hydrogen. It is found that there were many embrittled platforms, generally with large inclusions on the fracture surfaces of the specimens after normal tensile testing because of the trapping of the charged hydrogen around inclusion and the occurrence of hydrogen embrittlement. The size, composition, and distribution of these inclusions can be analyzed using a scanning electron microscopy, thus, the maximum inclusion size can be predicted using the SEV method. To verify the accuracy of the proposed method, additional inclusion rating methods of conventional optical metallographic observation and high-cycle fatigue testing were conducted. Using the proposed method, it was confirmed that the predicted maximum inclusion size and fatigue strength are consistent with that obtained via the rotating bending fatigue test. Therefore, the proposed method is a promising, efficient, and reliable for use in high-strength steels with high cleanliness to inspect the maximum size inclusion and predict fatigue strength.

Precise assembly of heterometallic complexes is a challenge. Here, the authors design a heterometallic triangular necklace through a highly efficient threading-and-ring-closing approach driven by metal-ligand coordination, which shows strong bacterium-binding and cell wall/plasma membrane-disrupting capacity for killing bacterial cells.

Fluorescent supramolecular coordination complexes are of interest for chemical sensing and optical devices. Here the authors synthesize nine organoplatinum metallacycles with high quantum yields, whose fluorescence wavelengths are tuned through manipulation of their photoinduced electron transfer and intramolecular charge transfer properties.

Chiral spirocyclic compounds are important structural motifs for drug discovery. Here, the authors report a synthetic route to spirocycles based on enantioselective cycloaddition of activated spirocyclopropyl oxindoles, which act as donor-acceptor cyclopropanes.

In the molecule of the title compound, C12H10N4, the two imidazole substituents are related by inversion symmetry and each forms a dihedral angle of 25.02 (8)° with the benzene ring. In the crystal, molecules are linked through N—H...N hydrogen bonds, forming cyclic units [graph-set R44(28)], which generate a layered structure extending across (011).

The title compound, C14H12N2O3·H2O, synthesized by the reaction of methyl 4-aminobenzoate with isonicotinoyl chloride hydrochloride, is relatively planar, with the pyridine ring being inclined by 7.46 (7)° to the benzene ring. In the crystal, the methyl 4-isonicotinamidobenzoate molecules are interlinked by water molecules via N—H...O, O—H...N and O—H...O hydrogen bonds, leading to the formation of a double-chain ribbon-like structure.

The Compton profiles of methane and ethane molecules have been determined at an incident photon energy of 20 keV based on the third generation synchrotron radiation, and the statistical accuracy of 0.2% is achieved near pz = 0. The density functional theory with aug-cc-pVTZ basis set was used to calculate the Compton profiles of methane and ethane. The present experimental Compton profiles are in better agreement with the theoretical calculations in the whole z region than the previous experimental results, which indicates that the present experimental Compton profiles are accurate enough to serve as the benchmark data for methane and ethane molecules. [ABSTRACT FROM AUTHOR]

Research has been conducted on silver(I) double salts containing 4-hydroxyquinoline ligand. The authors describe the synthesis of these salts carried out via the hydrothermal method.

Dissociative photoionization of 1,2-epoxyoctane was investigated by synchrotron radiation vacuum ultraviolet photons in the energy region of 9.8–16.6 eV under ultrasonic molecular beam. Dissociative fragment ions were measured with reflection time-of-flight mass spectrometer at different photon energies. Appearance potentials of the dominative ion fragments were determined through photoionization efficiency curves. The structures and energies of the parent, ionized and neutral radicals were obtained with G3 calculations. Through comparing the experimental results with the theoretical calculations, we proposed the dissociative channels for the photoionization of 1,2-epoxyoctane. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the anti-depressant-like activity of curculigoside from Curculigo orchioides Gaertn and its underlying mechanism(s). Methods: Antidepressant-like activity was determined in mice through forced swimming test (FST), tail suspending test (TST), and open field test (OFT). Mechanism of action was investigated by measuring levels of dopamine (DA), norepinephrine (NE), and 5-hydroxytryptamine (5-HT) in chronic mild stress (CMS) rats using high-performance liquid chromatography-electron capture detector (HPLC-ECD). Western blotting was used to investigate the effect of curculigoside on the expression of brain-derived neurotrophic factor (BDNF) protein in rats. Results: In FST and TST, treatment of mice with curculigoside (10, 20, 40 mg/kg, p.o.) significantly reduced immobility time, which was, however, unaffected by locomotor activity when assessed in the OFT. The treatment led to significant increases in DA, NE and 5-HT, and up-regulation of BDNF protein expression in the hippocampus of the CMS rats. Conclusion: These results demonstrate that curculigoside exerts significant anti-depressant-like activity on mice, the mechanism of which involves increase in the levels of DA, NE, 5-HT, and up-regulation of BDNF expression. Thus, curculigoside can be considered a potential drug candidate for the treatment of depressive disorders. [ABSTRACT FROM AUTHOR]

In this study, we reported an epitope imprinting method on the surface of core-shell magnetic nanoparticles (NPs) for the recognition of target bovine serum album (BSA). The epitope was selected as the template molecule from the nonapeptide of surface-exposed C-terminus of BSA. The core-shell magnetic epitope molecularly imprinted polymers (Fe[sub 3]O[sub 4]@EMIPs) exhibited a specific capture activity for the corresponding target protein, BSA. The magnetic NPs made it easy to separate the imprinted material from solution by an external magnetic field, and the thin imprinted layer presented fast kinetics for the rebinding of the target protein. Moreover, the Fe[sub 3]O[sub 4]@EMIPs could separate BSA from the bovine blood sample. The epitope imprinting approach combined with magnetic NPs provided an easy and fast method for the specific recognition of BSA. [ABSTRACT FROM AUTHOR]

A bicyclic host molecule 1 consisting of a pillar[5]arene and a 1,5-dioxynaphthalene-based crown ether unit has been synthesized, and the two cyclic subunits in 1 were found to recognize two different guest molecules (1,4-dicyanobutane and paraquat) selectively or take up the two guest molecules simultaneously. [ABSTRACT FROM AUTHOR]

A facile and efficient approach for preparation of ionic liquid functionalized silica-capped CdTe QDs (CdTe/ SiO[sub 2]/IL) was proposed in this work. The imidazolium-based ionic liquid N-3-(3-trimethoxysilylpropyl)-3-methyl imidazolium chloride was introduced and anchored on the surface of silica-capped CdTe QDs by the sol-gel technique, which played the role of a recognition element due to the covalent coordination binding between the heme group of hemoprotein and the imidazolium cation in the ionic liquid. The synthetic CdTe/SiO[sub 2]/IL was further characterized by elemental analysis, transmission electronic microscopy (TEM), X-ray photoelectron spectra (XPS) and Fourier transform infrared spectroscopy (FT-IR). Combining the merits of the fluorescence property of the QDs and the covalent interaction of the ionic liquid with hemoproteins, the CdTe/SiO[sub 2]/IL exhibited high adsorption capacity and good specificity toward hemoproteins and also was successfully applied in the fluorescence detection of hemoprotein in biological fluid. The strategy provided a promising way to fabricate functionalized fluorescence materials as biomedical/chemical sensors for the separation and detection of hemoproteins in proteomics research. [ABSTRACT FROM AUTHOR]

Mesoporous NiO single-crystalline nanosheet arrays grown on Ni foam with a thickness of about 5 μm have been fabricated by a facile hydrothermal approach and further investigated as a binder-free electrode for high-performance supercapacitors. Owing to the high conductivity of the single-crystalline NiO nanosheet arrays on the conducting substrate in combination with the large surface area provided by the mesoporous NiO nanosheets, the unique designed NiO nanosheet arrays on Ni foam have exhibited a high specific capacitance (674.2 F g-1 at a current density of 1 A g-1), good rate capability, and excellent cycling stability (93.5% capacitance retention after 5000 cycles). These results suggest that the singlecrystalline NiO nanosheet array electrode is a promising candidate for high-performance supercapacitors and the rational design of this unique binder-free electrode demonstrated in this work provides a new and facile approach to fabricate other transition metal oxide arrays for electrochemical energy storage. [ABSTRACT FROM AUTHOR]

A new three-dimensional (3D) metal-organic framework (MOF), [Zn3L2(DMF)2]·2DMF (1-Zn), was prepared by the reaction of 5-(4-carboxybenzoylamino)-isophthalic acid (H3L) with Zn(NO3)2.6H2O under solvothermal conditions. Interestingly, the zinc ions in the zinc-carboxylate chains of complex 1-Zn could be exchanged with copper ions via direct single-crystal to single-crystal transformation (SC-SC). The complete and irreversible exchange of the metal ions from Zn2+ to Cu2+ and retention of the framework structure were verified by powder X-ray diffraction (PXRD), ICP-AES and SEM-EDS. Solid state photoluminescence measurements showed metalspecific properties. [ABSTRACT FROM AUTHOR]

In this letter, a dual-polarized array antenna with wide bandwidth and high gain is presented for Wi-Fi/WiMAX application. The array antenna comprises a single substrate layer, a radiation patch layer, and conical elements. For comparison, an array antenna with two layers of substrates is designed. The reflection coefficient of the antenna with cones is better than -10 dB in the range of 4.9 ~ 5.96 GHz with a relative bandwidth of 19.52%, which is higher than that of the antenna with two substrate layers (14.05%). The maximum gains of the proposed antenna with cones achieve approximately 19.2 and 18.8 dBi at 5.5 GHz for the two orthogonal polarizations, respectively. In addition, high isolation and low cross-polarization levels are observed. [ABSTRACT FROM AUTHOR]

Myelodysplastic syndrome (MDS), characterized by the decreased production of blood cells, often progresses to acute myeloid leukemia (AML), a sign of poor prognosis of MDS. In AML, the Wnt/β-catenin pathway is aberrantly activated, suggesting that the increased pathway activity may be correlated with the development and prognosis of MDS. SOX7 protein, encoded by the sex-determining region Y-box 7 (SOX7) gene, inhibits the activity of the Wnt/β-catenin pathway. Because the DNA methylation can regulate the transcription of SOX7 gene, we used the methylation-specific PCR to investigate the methylation status of the CpG island in MDS patients to determine the potential correlation of the SOX7 methylation with the development and prognosis of MDS. We found that the CpG island of the SOX7 gene was methylated in 58.1% (97/167) of MDS patients, but not in any healthy control. Furthermore, the percentage of patients with the methylated CpG island of the SOX7 gene was significantly higher in patients at advanced stages of MDS than in the patients at early stages. The increased percentages of this SOX7 methylation were also correlated with age, marrow blast levels, and International Prognostic Scoring System (IPSS) risk. After prognostic analysis, we found that patients with the methylated CpG island of the SOX7 gene had shorter overall survival and cumulative survival than patients with unmethylated CpG island. Our findings suggest that the methylation of the CpG island of the SOX7 gene can be used as a predictive factor for the development and prognosis of MDS patients. [ABSTRACT FROM AUTHOR]

metagenomic library consisting of 3,024 bacterial artificial chromosome clones was prepared in Escherichia coli DH10B with high-molecular-weight DNA extracted from red soil in South China. A novel cellulase gene with an open reading frame of 1,332 bp, cel5G, encoding an endo-β-1,4-glucanase was cloned using an activity-based screen. The deduced enzyme, Cel5G, belongs to the glycosyl hydrolase family 5 and shares <39% identity with endoglucanases in the GenBank database. cel5G was expressed in E. coli BL21, and the recombinant enzyme Cel5G was purified to homogeneity for enzymatic analysis. Cel5G hydrolyzed a wide range of β-1,4-, β-1,3/β-1,4-, or β-1,3/β-1,6-linked polysaccharides, amorphous cellulose, filter paper, and microcrystalline cellulose. Its highest activity was in 50 mM citrate buffer, pH 4.8, at 50°C. Cel5G is stable over a wide range of pH values (from 2.0 to 10.6) and is thermally stable under 60°C. It is highly tolerant and active in high salt concentrations and is stable in the presence of pepsin and pancreatin. The K and V values of Cel5G for carboxymethyl cellulose are 19.92 mg/ml and 1,941 μmol min mg, respectively. These characteristics indicate that Cel5G has potential for industrial use. [ABSTRACT FROM AUTHOR]

Background: In vertebrates, Ran-Binding Protein in the Microtubule Organizing Center (RanBPM) appears to function as a scaffolding protein in a variety of signal transduction pathways. In Drosophila, RanBPM is implicated in the regulation of germ line stem cell (GSC) niche organization in the ovary. Here, we addressed the role of RanBPM in nervous system function in the context of Drosophila larval behavior. Methodology/Principal Findings: We report that in Drosophila, RanBPM is required for larval feeding, light-induced changes in locomotion, and viability. RanBPM is highly expressed in the Kenyon cells of the larval mushroom body (MB), a structure well studied for its role in associative learning in Drosophila and other insects. RanBPM mutants do not display major disruption in nervous system morphology besides reduced proliferation. Expression of the RanBPM gene in the Kenyon cells is sufficient to rescue all behavioral phenotypes. Through genetic epistasis experiments, we demonstrate that RanBPM participates with the Drosophila orthologue of the Fragile X Mental Retardation Protein (FMRP) in the development of neuromuscular junction (NMJ). Conclusions/Significance: We demonstrate that the RanBPM gene functions in the MB neurons for larval behavior. Our results suggest a role for this gene in an FMRP-dependent process. Taken together our findings point to a novel role for the MB in larval behavior. [ABSTRACT FROM AUTHOR]

A new transition prediction model is introduced, which couples the intermittency effect into the turbulence transport equations and takes the characteristics of fluid transition into consideration to mimic the exact process of transition. Test cases include a two-dimensional incompressible plate and a two-dimensional NACA0012 airfoil. Performance of this transition model for incompressible flows is studied, with numerical results consistent to experimental data. The requirement of grid resolution for this transition model is also studied. [ABSTRACT FROM AUTHOR]

The Drosophila disconnected ( disco) gene encodes a C2H2-type zinc finger transcription factor required for the development of the central and peripheral nervous systems. We report that disco participates in a positive feedback loop with the Dll gene, a master regulator of ventral appendage development. Dll function is not only required for proper disco expression in antenna and leg discs, but is also sufficient for ectopic expression of disco in the developing retina and wing imaginal discs. Conversely, disco gene function is required for the maintenance of Dll expression. We show that Dll phenotypes are partially rescued by the up-regulation of disco expression in the Dll domain. Reduction in disco gene function disrupts antenna and leg development, and the phenotypes closely resemble that produced by Dll alleles. These observations demonstrate that disco plays a fundamental role in the Dll-dependent patterning of antenna and leg, perhaps as a regulator of Dll gene expression. [ABSTRACT FROM AUTHOR]

Under self-assembly conditions, the interaction between pyrimidinyl-containing oxacalixaromatics (1and 2) and silver cation resulted in the formation of two-dimensional coordination networks 3and 4; single crystal X-ray analysis revealed that complex 3featured a coordination polymeric structure with ligand 1arranged in an offset manner along the polymeric chain, while network 4featured a structure with regular microcyclic channels. [ABSTRACT FROM AUTHOR]

Three polyoxometalate-based silver(I) ethynediide complexes have been obtained by hydrothermal synthesis. New types of polyoxometalate motifs are generated and stabilized in a silver-rich environment in their respective three-dimensional coordination frameworks via assembly of the polyhedral metal—ligand C2@Agn (n = 6 and 7) supramolecular synthon. [ABSTRACT FROM AUTHOR]

Quinidine derivative (QD)2PYR was found to catalyze the asymmetric direct amination of unprotected prochiral 3-oxindole with DIAD to construct quaternary stereocenters at the C3 position with excellent enantioselectivity. [ABSTRACT FROM AUTHOR]

The research progress in thermal aging resistant silicone rubber based heat-proof materials in recent years was reviewed with 46 references. The inorganic modification effects of nano-carbon materials, graphite powder, talc powder, transition metal oxides and fiber fillers on the thermal aging resistance and mechanical properties of silicone rubber based heat-proof materials were emphatically introduced, and the main research directions of thermal aging resistant silicone rubber based heat-proof materials in the future were pointed out.

The experimental Compton profile of the propane molecule is measured at an incident photon energy of 20 keV based on the third generation synchrotron radiation, and the statistical accuracy of 0.2% is achieved near pz = 0. The calculated Compton profile by the density functional theory with aug-cc-pVTZ basis set reproduces the experimental observation very well. The joint experimental and theoretical investigation provides the benchmark data of the electronic structure of propane. [ABSTRACT FROM AUTHOR]