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Mg1-x-ySryAl2O4:Eu2+x blue phosphor particles for white light-emitting diodes (LEDs) were prepared by a solid-state reaction method, and their luminescent properties were investigated with the change in the concentration of the activator and the composition of the host matrix. The phosphor particles were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, and fluorescence spectrophotometer. The luminescence of Eu2+-activated MgAl2O4 has shown a strong blue emission dominant peak around 460 nm, and the highest intensity was observed when the content of Eu2+ was 2 mol %. The substitution of 1-10% Sr2+ ions instead of the Mg2+ greatly enhanced the 460 nm blue emissions, especially for samples excited by UV in the range of 350-400 nm. The optimized phosphor Mg0.92Sr0.06Al2O4:Eu2+0.02 has shown 10 times emission intensity compared with that of the Mg0.98Al2O4:Eu2+0.02 phosphor when they were excited by a 365 nm UV light. The luminescent properties of Mg1-x-ySryAl2O4:Eu2+x were investigated by changing the ratio of Sr2+ to Mg2+. For Sr2+-doped MgAl2O4:Eu2+, the photoluminescence increased by about 6%. The mechanism for the improvement was discussed. No obvious degradation problem of the synthesized Sr2+-doped samples due to the moisture in the laboratory atmosphere could be found. [ABSTRACT FROM AUTHOR]

Al3+/Mg2+ doped Y2O3:Eu phosphor was synthesized by the glycine-nitrate solution combustion method. In contrast to Y2O3:Eu which showed an irregular shape of agglomerated particles (the mean particle size >10 μm), the morphology of Al3+/Mg2+ doped Y2O3:Eu crystals was quite regular. Al3+/Mg2+ substituting Y3+ in Y2O3:Eu resulted in an obvious decrease of the particle size. Meanwhile, higher the Al3+/Mg2+ concentration, smaller the particle size. In particular, the introduction of Al3+ ion into Y2O3 lattice induced a remarkable increase of PL and CL intensity. While, for Mg2+ doped Y2O3:Eu samples, their PL and CL intensities decreased. The reason that causes the variation of PL and CL properties for Al3+ and Mg2+ doped Y2O3:Eu crystals was concluded to be related to sites of Al3+ and Mg2+ ions inclined to take and the difference of ion charge. [ABSTRACT FROM AUTHOR]

Through the review and summary of the 5th national clinical skill competition of acupuncture-moxibustion and tuina , it is recognized that the strict security of training, the concentrated training items, active competition of training and the diversity of training patterns are the keys of achievement. Besides, the suggestions are proposed in terms of tuina manipulations and the recitation content of classic in competition. It hopes that the competition greatly play its role in promoting learning, teaching and education construction.

Objective: To observe the effect of "Shuanggu Yitong" (Double-reinforcing and one-unblocking) needling [electroacupuncture (EA) of "Guanyuan" (CV 4), "Housanli" (ST 36), "Fenglong" (ST 40) and "Zhongwan" (CV 12)] on expression of hypothalamic phosphatidylinositol 3-kinase (PI 3 K) and p-PI 3 K proteins in insulin resistance rats., Methods: Sixty Wistar rats were randomized into normal control, model, EA prevention, EA, cerebrospinal fluid (CSF), and Wortmannin (PI 3 K antagonist) groups (n = 10 rats/group). Insulin resistance model was established by feeding the animal with high fat forage continuously for 8 weeks. For rats of the EA group, EA (2 Hz, 1 mA) was applied to ipsilateral "Housanli"(ST 36)-"Fenglong" (ST 40), and "Guanyuan" (CV 4)-"Zhongwan" (CV 12) for 15 min, once daily, 5 times a week and for 8 weeks, beginning after modeling. For rats of the EA prevention group, EA was conducted simultaneously with the modeling. For rats of the Wortmannin group and CSF group, cerebroventricular microinjection of Wortmannin (50 nmol/L, 3 mg/kg) or artificial CSF was given through an implanted steel cannel. Fasting plasma glucose (FPG) and fasting serum insulin (FINS) contents were assayed using glucose-tested instrument and ELISA respectively, insulin activity index (IAI) was calculated [IAI = Ln (1/FPG x FINS)], and the expres- sion of hypothalamic PI 3 K and p-PI 3 K proteins was detected by Western blot., Results: In comparison with the normal control group, the body weight (BW), FPG and FINS contents at time-points of 8 and 16 weeks were considerably increased (P < 0.01), and IAI, hypothalamic PI 3 Kp 110 and p-PI 3 Kp 110 protein expression levels were obviously decreased in the model group (P < 0.01). Compared with the model group, the FPG and FINS contents at the 8th week after modeling in the EA prevention group, the BW and FPG levels at the 16th week in the EA prevention, EA and CSF groups, FINS levels at the 16th week in the EA prevention and EA groups were remarkably decreased (P<0.05, P<0.01), IAI, and hypothalamic PI 3 Kp 110 and p-PI 3 Kp 110 protein expression levels were significantly up-regulated in the EA prevention, EA and CSF groups (P < 0.05, P < 0.01). No significant differences were found among the EA prevention, EA and CSF groups, and between the model and Wortmannin groups in the BW, FPG, FINS, IAI and hypothalamic PI 3 Kp 110 and p-PI 3 Kp 110 expression levels (P > 0.05)., Conclusion: EA intervention can reduce insulin resistance by suppressing the increase of body weight, blood glucose and insulin contents, and increasing hypothalamic PI 3 K expression levels in insulin resistance rats.

Objective: To establish HPLC fingerprint of flavonoids and phenols of Dendrobium nobile., Methods: Phenomenex prodigy ODS(3) C18 column (250 mm x 4.6 mm, 5 microm) was used with a mixture of acetonitrile-0.1% acetic acid as the mobile phase in a gradient mode, the column temperature was 25 degrees C, the flow rate was 1.0 mL/min, and the detection wavelength was 254 nm., Results: The flavonoids and phenols of Dendrobium nobile were well separated, and 10 fingerprint peaks in common were confirmed., Conclusion: This method is simple, accurate with good reproducibility, and can be used specifically for the quality control of Dendrobium nobile.