Experimental Research on the Dynamic Energy Absorbing Capacity of the Honeycomb Paperboard Filled with Polyurethane

A kind of composite buffering material was made by filling the voids of honeycomb paperboard with polyurethane. Drop tests were performed to evaluate the dynamic energy absorption capacity of the material. Based on the tests results,the mechanical behaviors of the material under low velocity dynamic impact conditions were analyzed. It was shown that the absorbed energy of the composite material varies inversely with the void diameter. The absorbed energy of the composite material is 1- 2 times than that of honeycomb paperboard and polyurethane. The energy absorption efficiency of the composite material is better than those of honeycomb paperboard and polyurethane.

Preparation of Elemental Tellurium Nanoparticles-Sucrose Sol and Its Antioxidant Activity in Vitro

The elemental tellurium nanoparticles （TeNPs） - sucrose sol was prepared by the reaction of sodium tellurite with ascorbic acid in sucrose aqueous solution. The results indicated that TeNPs were dispersion excellent in the TeNPs - sucrose sol and the morphology of TeNPs was needle-like with about 70 nm in width and 500 nm in length. The antioxidant activity of the TeNPs - sucrose sol in vitro was estimated by pyrogallol autoxidation method, Fenton method and oxygen radical absorbance capacity （ORAC） assay. The results showed that a certain amount of TeNPs - sucrose sol could effectively scavenge superoxide anion free radical and hydroxyl free radical with scavenging rates of 73 % and 57 %, respectively. ORAC assay was used to measure the total antioxidant capacity of TeNPs - sucrose sol. The order of ORAC values was 2.25 μmol.L-1 TeNPs - 0.025 % sucrose sol 〉 0.025 % sucrose 〉 2.25 μmol.L-1 Na2TeO3 〉 1.63 μmol.L-1 ascorbic acid. The results suggested that the TeNPs - sucrose sol had the excellent antioxidant activity and TeNPs were the dominating contributors to antioxidant capacity of the TeNPs - sucrose sol.

Zea mays L. Pollen： An Approach to Its Quality Control

Zea mays L. is one of the biggest cropping systems among the sustainable development agronomy. Pollen from this crop source is unexplored and apiculture can be a good partner adding value to the product and creating new jobs helping to solve some social issues as unemployment. However, food safety is crucial, thus the aim of this study was to explore the flavonoid/phenolic profiles from Z. mays L. pollen as a fingerprint for this plant identification and also to demonstrate how the method of bee pollen samples （honeybee collected pollen） is applied. For this purpose, several sources ofZ. mays L. pollen were analyzed, including corn hybrids and genetic modified samples collected at the breeding fields. For this work, samples were taken at several years from 2000 to 2012 and collected from different countries and locations, such as Portugal, Mexico and Brazil. Results showed, for the first time, that the fingerprint （flavonoid/phenolic profile） for Z. mays L. pollen does not change over the time of sampling neither with the region of harvesting. The high performance liquid chromatography-diode array detector （HPLC/DAD） fingerprints of phenolic/flavonoid extract from Z. mays remain unchanged for all samples analyzed from different countries, hybrids and/or genetic modified plants. This is also the first study reporting these phenolic compounds not only in pollen collected directly from hybrid plants, but also in Z. mays bee pollen. The described fingerprinting method is easy, fast and accurate for the characterization of Z. mays L. pollen samples and complete microscopic analysis because it is species-specific.

Effects and Potential Mechanisms of Danzhi Xiaoyao Pill(丹栀逍遥丸) on Proliferation of MCF-7 Human Breast Cancer Cells in vitro

Objective： To investigate the effects of 50% ethyl alcohol （EtOH） extracts from Danzhi Xiaoyao Pill （丹栀逍遥丸, DXP） on the proliferation of MCF-7 human breast cancer cells and potential mechanisms. Methods： ATP-Lite assay was performed to test the proliferation of the MCF-7 breast cancer cell line; and antioxidant activity was measured by the oxygen radical absorbance capacity （ORAC）. The effects of DXP on nitric oxide （NO） production were tested by lipopolysaccharide （LPS）- stimulated RAW 264.7 murine macrophages using the Griess reaction. Results： The 50% EtOH DXP extracts displayed a cytotoxic response on MCF-7 cells at 0.10, 0.25 and 0.50 mg/mL dosedependently with the proliferation inhibited by more than 85%. The ORAC value of the DXP was 820μ moL Trolox equivalent/g, about 40% of the vitamin C value. DXP extracts had significant inhibitory effect on NO production at the concentration from 0.0625 mg/mL to 0.5 mg/mL （P〈0.05, P〈0.01）. Conclusion： The extracts of DXP could significantly inhibit the proliferation of MCF-7 cells, with the effect possibly related to its antioxidant activity and the inhibition of NO production.