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Ion-responsive probes have gathered significant attention because of health and environmental factors, but there are few reports on the “turn-on” mechanism of Fe3+and sensitive detection of Br–by fluorescence measurement. Herein, a green luminescence material, N-5-acetyl-2-hydroxy-benzamide-1,4,7-triazacyclononane (btacn), was successfully synthesized for the first time and comprehensively characterized. As expected, btacn exhibits high sensitive, but nonspecific, extensive interaction with Cu2+, Co2+, Zn2+, Mn2+, and Fe3+ions. Therefore, to improve the specificity of the probe, we tried to synthesize transition metal complexes of btacn, but all failed except Zn(btacn)Cl2. In addition, the preformed complex, Zn(btacn)Cl2, was used as a special “turn-on” chemosensor for detecting trace amounts of Br–and Fe3+. The electrostatic interaction with Fe3+and the hydrogen bond of PhO-H···Br–leads to obvious changes in the electronic cloud of Zn(btacn)Cl2, which are reflected in different spectral responses.

The joining of Mg alloy to steel was realized by metal inert-gas arc welding, and the weld thermal cycle characteristics and Mg–steel joints were investigated. The results show that the temperature distribution in the joints is uneven. Mg alloy welds present a fine equiaxed grain structure. There exists a transition layer consisting mainly of AlFe, AlFe3and Mg(Fe, Al)2O4phases at Mg/steel interface, and it is the weakest link in Mg–steel joints. The welding heat input and weld Al content have the significant effect on the joint strength. The joint strength increases with increasing the heat input from 1680 J/cm to 2093 J/cm, due to promoting Mg/steel interface reaction. When weld Al content is increased to 6.20%, the joint strength reaches 192 MPa, 80% of Mg alloy base metal strength. It is favorable to select the suitable welding heat input and weld Al content for improving joint strength.

We report on blue phosphorescent organic light-emitting diodes (PHOLEDs) with biphenyl (Spiro[fluorene-9,9′-xanthen]-2-yl) phosphine oxide（SFX2PO）host. The device studied in this work has the structure of ITO/m-MTDATA:MoOx(10nm)/m-MTDATA(30nm)/ TAPC(10nm)/SFX2PO: Firpic(10nm)/Bphen(40nm)/LiF(1nm)/Al(200nm), in which maximum luminance of 8950 cd/m2 and power efficiency of14.65 lm/w have been achieved.

Watermelon [Citrullus lanatus(Thunb.) Matsum. & Nakai var. lanatus] production in the same field without rotation of crops leads to disease buildup and poor yields. The purpose of this research was to evaluate the influences of root exudates produced by watermelon cultivars susceptible or resistant to the pathogen Fusarium oxysporum f. sp. niveum (FON). At low concentrations of root exudates (<50 mg L−1), the susceptible cultivar stimulated the growth of FON but the resistant cultivars inhibited FON at high concentration (200 mg L−1). Mycotoxin production was increased more in the presence of exudates from susceptible than resistant cultivars and after flowering than before flowering. Activities of enzymes (protease, pectinase, cellulose, and amylase) were stimulated more in resistant than susceptible cultivars by FON. Also, there were higher ratios of antifungal phenolic acids (p‐hydroxybenzoic, phthalic, gallic, coumaric, cinnamic, ferulic, salicylic, and sinamic acids) to fungus‐stimulating phenolic acids (vanillic and syringic acids) in resistant cultivars than in susceptible ones both before and after flowering. Breeding of resistant cultivars containing more antifungal agents is a strategy that, if pursued, could lead to a reduction in the occurrence of watermelon wilt disease, especially when rotation of crops is not possible.

AbstractWilt disease of watermelon caused by Fusarium oxysporumf. sp. niveumin long-term monoculture system has been much often found particularly in protected land cultivation system worldwide. Fusaric acid (FA), a fungal phytotoxin, was extracted from F. oxysporumf. sp. niveumisolated from diseased watermelon plant. The influence of FA on the biomass and leaves photosynthesis of watermelon seedlings was investigated in a laboratory study. Results obtained are listed as follows. Plant height, fresh weight, main root length and lateral roots of watermelon seedling exposed to FA (400 mg·L−1) for 12 hours and then grown in ordinary condition for nine days were decreased by 23.0%, 23.1%, 23.6% and 33.6% compared with control respectively. Cotyledons were wilted to death completely and necroses occurred on the first true leaf and the upper leaves had become crinkled and chlorosis, which was a typical symptom of wilting disease of watermelon. And thus physiological functions were inhibited and damaged strongly. Net photosynthesis rate, stomatal conductance, intercellular CO2concentration, and chlorophyll (SPAD reading) of the seedlings decreased with the increasing of concentrations of FA and duration of exposure to FA. Compared with control, stomatal conductances of leaves treated with FA weredeclined by 87.4-98.4% and net photosynthesis rates of leaves were decreased by 51.8-92.1%. Intercellular CO2concentration of the seedlings treated with FA was reduced by 66.6 -94.8%. Chlorophyll content in the leaves of the seedlings was decreased by 42.7-72.3%. Transpiration rate fell down to 86.8-96.3%. It was concluded that FA strongly reduced the chlorophyll content of watermelon seedlings leaves resulting to heavy suppression of leaf photosynthesis, which therefore affected seedlings growth finally leading to leaf wilting and necrosis.

Postherpetic neuralgia (PHN) is a painful, long-lasting condition as a consequence of nerve damage resulting from a herpes zoster infection. Although there are many different treatments available to reduce pain duration and severity, PHN is often refractory to them and no single therapy shows an effective cure for all cases of PHN, especially for those involving the ophthalmic branch of the trigeminal nerve. Pulsed radiofrequency (PRF) is a minimally invasive procedure for pain treatment that has been practiced over the past decade. However, its clinical efficacy and safety for treating PHN involving the ophthalmic branch of the trigeminal nerve have not been evaluated. Objective. This study aimed to evaluate the efficacy and safety of PRF for treating PHN involving the ophthalmic branch of the trigeminal ganglion. Study Design. An observational study. Setting. All patients received PRF of the ophthalmic branch of the trigeminal nerve, pain intensity was assessed by a visual analogue scale (VAS), and complications before and after PRF stimulation were noted. Methods. Thirty-two patients with PHN of the ophthalmic branch were treated by PRF of the ophthalmic branch with controlled temperature at 42°C for 8 min. Pain relief, corneal reflex, sleep quality, and satisfaction were assessed for all patients. Results. Thirty out of 32 patients (93.75%) reported significant pain reduction after PRF treatment. Twenty-eight of them (87.5%) were satisfied with their sleep and obtained a pain score lower than 3 following the procedure. Only two patients had a recurrence of the severe burning pain and returned to the hospital for other medical therapies 2 weeks after the PRF procedure. No patient lost the corneal reflex. Limitations. This study is an observational study and a nonprospective trial with a short-term follow-up period. Conclusion. PRF of the trigeminal ganglion of the ophthalmic branch can significantly reduce pain sensation and improve sleep quality and satisfaction for PHN of the ophthalmic branch.