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Reduced-activation ferritic/martensitic (RAFM) steels, based on Fe-Cr alloys, have been considered to be one of the most promising candidate structural materials for future fusion reactors. Dislocation loops, as one of the most common microstructures induced by radiation, are the key factors in the deterioration of material properties. Dislocation loops with different Burgers vectors have different effects on material properties. Currently, a consensus exists suggesting that there are two kinds of dislocation loops with Burgers vectors of 1/2 〈111〉 and 〈100〉 in bcc iron-based alloys. In this study, the Burgers vectors of dislocation loops formed at the annealing temperatures of 400, 500, and 550℃ in hydrogen-ion implanted Fe-9%Cr model alloy were examined based on dislocation loop maps and dislocation loop invisibility criteria. Dislocation loop maps manifest such that under the 〈100〉 or 〈110〉 zone axes, it is easy to distinguish 1/2 〈111〉 and 〈100〉 edge dislocation loops, while under the 〈111〉 zone axis, the loops cannot be distinguished. By direct comparison between loop maps and loop images obtained through transmission electron microscope (TEM), the dislocation loops with Burgers vectors of 1/2 〈111〉 and 〈100〉, formed at different annealing temperatures, were characterized. The results of the characterization show that with increasing annealing temperature, the size of the dislocation loops increases while density decreases. Furthermore, the proportion of dislocation loops with a Burgers vector of 〈100〉 increases with rising temperature. After annealing at 400℃ and 500℃, the percentages of 〈100〉 type dislocation loops are 16.48% and 92.78% respectively, in hydrogen-ion implanted Fe-9%Cr alloy. While the temperature is raised to 550℃, all the dislocation loops are of 〈100〉 type loops. This indicates that the transition temperature range of dislocation loops in Fe-9%Cr is 400℃-500℃. Compared with pure iron, the presence of Cr element promotes the transition temperature of dislocation loops from 1/2 〈111〉 type to 〈100〉 type.

The EtOH extract of the roots and rhizomes of Clematis chinensis afforded two new macrocyclic glucosides clemochinenosides C (1) and D (2). Their structures were elucidated on the basis of spectroscopic means and hydrolysis products. These compounds were evaluated for inhibitory activity against lipopolysaccharides-induced TNF-α production in RAW 246.7 macrophages. Compounds 1 and 2 showed moderate inhibitory activity with IC50 values of 12.9 ± 2.3 and 18.4 ± 2.7 μM, respectively. In addition, a proliferation study was used to evaluate the anti-angiogenic effects of these compounds in vitro (VEGF-induced human umbilical vein endothelial cell proliferation). Compounds 1 and 2 displayed weak inhibitory effects with inhibition rates of 26.3 ± 1.8 and 19.2 ± 2.6% at 50 μM, respectively. [ABSTRACT FROM AUTHOR]

Previous epidemiological studies have revealed the anti-cancer effect of dietary circulating carotenoids. However, the protective role of specific individual circulating carotenoids has not been elucidated. The purpose of this study was to examine whether serum carotenoids, including α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin, could lower the risk for breast cancer among Chinese women. A total of 521 women with breast cancer and age-matched controls (5-year interval) were selected from three teaching hospitals in Guangzhou, China. Concentrations of α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin were measured using HPLC. Unconditional logistic regression models were used to calculate OR and 95 % CI using quartiles defined in the control subjects. Significant inverse associations were observed between serum α-carotene, β-carotene, lycopene, lutein/zeaxanthin and the risk for breast cancer. The multivariate OR for the highest quartile of serum concentration compared with the lowest quartile were 0·44 (95 % CI 0·30, 0·65) for α-carotene, 0·27 (95 % CI 0·18, 0·40) for β-carotene, 0·41 (95 % CI 0·28, 0·61) for lycopene and 0·26 (95 % CI 0·17, 0·38) for lutein/zeaxanthin. However, no significant association was found between serum β-cryptoxanthin and the risk for breast cancer. Stratified analysis by menopausal status and oestrogen receptor (ER)/progesterone receptor (PR) showed that serum α-carotene, β-carotene, lycopene and lutein/zeaxanthin were inversely associated with breast cancer risk among premenopausal women and among all subtypes of ER or PR status. The results suggest a protective role of α-carotene, β-carotene, lycopene and lutein/zeaxanthin, but not β-cryptoxanthin, in breast cancer risk. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports the influences of the herbicide butachlor (n-butoxymethl-chloro-2′, 6′-diethylacetnilide) on microbial respiration, nitrogen fixation and nitrification, and on the activities of dehydrogenase and hydrogen peroxidase in paddy soil. The results showed that after application of butachlor with concentrations of 5.5 µg/g dried soil, 11.0 µg/g dried soil and 22.0 µg/g dried soil, the application of butachlor enhanced the activity of dehydrogenase at increasing concentrations. The soil dehydrogenase showed the highest activity on the 16th day after application of 22.0 µg/g dried soil of butachlor. The hydrogen peroxidase could be stimulated by butachlor. The soil respiration was depressed within a period from several days to more than 20 days, depending on concentrations of butachlor applied. Both the nitrogen fixation and nitrification were stimulated in the beginning but reduced greatly afterwards in paddy soil. [ABSTRACT FROM AUTHOR]

A bacterium (designated strain Y1) degrading acetanilide herbicide mefenacet was isolated from aerobic sludge. Based on the analyses of partial 16S rRNA gene, cellular fatty acid and BIOLOG-GN, and general physiological and biochemical characteristics, strain Y1 was identified as Sphingobacterium multivolum. Strain Y1 was able to degrade mefenacet used as sources of carbon and energy. Degradation of mefenacet was accompanied by producing the metabolites N-methylaniline and an unidentified compound with molecular weight 205, indicating a metabolic pathway of mefenacet initiated by hydrolysis of amido bond.