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1 Twenty-one cases out of 272 patients of acute organophosphates poisoning were diagnosed as intermediate syndrome (IMS) with a prevalence at 7.7%. The responsible OP insecticides included parathion, omethoate and some OP containing pesticide mixtures. IMS occurred mainly in severe OP poisoning patients who recovered from the acute cholinergic crisis at 7-75 h after the onset of acute poisoning. 2 Muscular weakness appeared in the following three categories of muscles: (1) neck flexors and proximal limb muscles; (2) muscles innervated by motor cranial nerves and/or (3) respiratory muscles. Blood acetylcholinesterase activity was persistently inhibited. Electroneuromyography (ENMG) with repetitive nerve stimulation (RNS) at frequencies of 20 Hz or 30 Hz in seven patients showed decrements of common muscle action potentials during the presence of myasthenia in five patients and became normal when their muscle strength recovered. 3 Mild IMS recovered within 2-7 days and had a favorable prognosis. Severe IMS patients with respiratory paralysis needed immediate endotracheal intubation and mechanical ventilation. Recovery of weakness of the respiratory muscles and proximal limb muscles took longer, the slowest being 30 days. Four of the patients died of respiratory paralysis and the fatality rate was 19%. 4 The mechanism of IMS remains to be further investigated. The RNS/ENMG changes indicate a post-synaptic block at the neuromuscular junctions. 5 In order to promote the recognition of this syndrome, we proposed to name the syndrome as Intermediate Myasthenia Syndrome (IMS).

The design, fabrication, and measurement of a metamaterial with broadband microwave absorption properties in the low frequency range are presented in this paper. The metamaterial has a layered structure with a thickness of 2.2 mm, and consists of a conventional printed circuit board (PCB) process fabricated cross array on the surface of a flake-shaped carbonyl iron (CI) powder-filled silicon rubber composite magnetic substrate backed by a metal plane. The measurement results indicate that the absorption bandwidth (defined as the frequency range with reflection coefficient below −10 dB) of the proposed structure is 2.55 GHz–5.68 GHz. The power loss mechanism was outlined according to the current distribution on and off the resonance frequency. Moreover, the absorption performance of the proposed structure for incident angles ranging from 0° to 60° for both transverse electric (TE) wave and transverse magnetic (TM) waves were exhibited.

To investigate the oxidative damage of mice induced by diisobutyl phthalate (DiBP) and the mechanism of free radical oxidative damage caused by DiBP.Sixty KunMing mice were divided by weight into 5 groups after accommodation to the experimental animal room for 3 days. The control group and 4 DiBP groups, group I, II, III and IV, were given DiBP in corn oil by gavages at the dosage of 0, 50, 250, 500 and 1000 mg/kg respectively. The mice were fed with normal diets and drinking water freely for 8 weeks. By the end of the experiment, the comet assay of blood and SOD, GSH-Px, MDA and 8-OHdG of liver were tested.The activities of SOD and GSH-Px in DiBP groups were significantly lower than the control group (P0.05); the MDA contents of DiBP group III and group IV were significantly higher than the control group (P0.05) and the 8-OHdG content of group II was significantly higher than the control group (P0.01). The comet assay showed that the oxidative damage of DNA in DiBP groups was significant in comparison with the control group (P0.05).Oxidative stress induced by diisobutyl phthalate can decrease the activities of antioxidative enzymes and result in oxidative damage of tissues.

At frequencies below 2 GHz, conventional microwave absorbers are limited in application by their thickness or narrow absorption bandwidth. In this paper, we propose and fabricate an ultra-thin broadband active frequency selective surface (AFSS) absorber with a stretching transformation (ST) pattern for use in the ultrahigh-frequency (UHF) band. This absorber is loaded with resistors and varactors to produce its tunability. To expand the tunable bandwidth, we applied the ST with various coefficients x and y to the unit cell pattern. With ST coefficients of x = y = 1, the tunability and strong absorption are concisely demonstrated, based on a discussion of impedance matching. On analyzing the patterns with various ST coefficients, we found that a small x/y effectively expands the tunable bandwidth. After this analysis, we fabricated an AFSS absorber with ST coefficients of x = 0.7 and y = 1. Its measured reflectivity covered a broad band of 0.7–1.9 GHz below −10 dB at bias voltages of 10–48 V. The total thickness of this absorber, 7.8 mm, was only ∼λ/54 of the lower limit frequency, ∼λ/29 of the center frequency, and ∼λ/20 of the higher limit frequency. Our measurements and simulated results indicate that this AFSS absorber can be thin and achieve a broad bandwidth simultaneously.

The performance of carbon fiber reinforced composites is to a great extent dictated by the interfacial adhesion strength between the fibers and matrix. In order to improve the interfacial properties of carbon fiber/polypropylene (PP) composites, a new surface treatment has been developed to graft the amine-capped cross-linked polyphosphazenes (ACP) onto carbon fibers as a novel coupling agent through in situ polycondensation between hexachlorocyclotriphosphazene (HCCP) and 4,4′-diaminodiphenyl ether (DDE) under mild reaction conditions, and maleic anhydride grafted PP (M-PP) was used as the matrix. The chemical composition of the modified carbon fibers was verified by Fourier-transform infrared (FTIR) spectra and X-ray photoelectron spectra (XPS). The surface morphologies of the modified carbon fibers were detected by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The interfacial shear strength (IFSS) between carbon fibers and the matrix was investigated by a microbond test. The grafted ACP with a quantity of amine groups uniformly covered the carbon fiber surfaces, which results in strong interfacial adhesion between the modified carbon fibers and M-PP. The results of the test reveal a significant improvement of IFSS in the ACP grafted carbon fiber composites with an increase of 223.0% compared to the unmodified carbon fiber composites. In this work, we propose a facile and effective method for improving the interfacial properties of carbon fiber composites by grafting a novel coupling agent.

Five diarylethene derivatives with 2-(2-pyridyl)imidazole as the ethene bridges (PI-BTEs) were synthesized and characterized. The structures and performances of the PI-BTEs (L1–L5) could be modified from not only the thiophene unit, but also the substituent on the imidazole nitrogen. Noteworthily, replacing the thiophene with the benzothiophene, the fatigue resistance is significantly improved, the centre absorption bands of the closed forms shift from 572 nm (L3) to 550 nm (L2), and the colours of the solutions change from pale pink in L3 to red-purple in L2. Additionally, the Stokes shift (Δν) values of L3 in various solvents display good linear relationships with the donor number (DN) of the solvents, and the solvent polarity parameter Δf.

This review article briefly outlines the development of metal-based chromophores as sensitizers for efficient lanthanide luminescence. Particularly, the synthetic strategies are highlighted on the designed heteronuclear lanthanide complexes by multi-functional bridging ligands with various coordination modes and potential coordination ability in our group. Finally, conclusions on our works and the research trends on such topic in the near future are given.