Oxidative stress is mainly induced by reactive oxygen species (ROS) such as hydroxyl radicals ( · OH), hydrogen peroxide (H 2 O 2 ), and superoxide radical anions (O 2 Ϫ˙) . The adverse effects of oxidative stress have been demonstrated in several groups of diseases, including cardiovascular disease and heart disease, 1,2) liver injury, 3) acute and chronic renal damage, 4) and cancer. 5) These negative effects are mainly caused by the formation of free radicals and mediated by free radical damage to lipids, proteins, and DNA. 6) Many reports have shown that natural products and their derivatives can protect against ROS-induced damage. Accordingly, they may have potential applications in preventing and/or curing diseases. 7,8) In recent years, traditional Chinese herbs have been found to possess excellent antioxidant activities [9][10][11][12][13][14] ; the phenolic and flavonoid components, in particular, have been identified as excellent antioxidants that have proven to be effective in scavenging free radicals. [15][16][17] Therefore, the use of herbs to inhibit oxidative stress and decrease damage from free radicals has garnered much attention.More than 2000 herbs have been recorded in the Compendium of Materia Medica, one of the most famous ancient Chinese herb books, and most of these traditional Chinese herbs were applied in the form of multi-herb formulas in medical treatments and as dietary supplements. However, the application of herbal prescriptions today is mainly based on a doctor's experience and not on pharmacological mechanisms.18) Traditional Chinese herb pairs (TCHPs), which are the basic unit in traditional Chinese prescriptions and an intermediate point between single herbs and multi-herb recipes, 19) consist of two relatively standard single herbs. Many herb pairs were recorded in the Treatise on Febrile and Miscellaneous Diseases and in the Synopsis of the Golden Chamber. According to Chinese records and the classic books about herbs in China, many TCHPs showed significantly better pharmacological efficacy than when the herbs were used individually. [20][21][22][23] For instance, the complete Qizhu Tang formula (composed of four herbs) was more effective in preventing cerebral oxidative injury in rats than any of the incomplete formulas or single herbs. 24) A TCHP, Astragalus membranaceus and Paeonia lactiflora (AME-PL), inhibited liver fibrosis in rats treated with carbon tetrachloride, and exhibited an increased hepato-protective capability relative to either of the herbs used individually. 20) However, the mechanisms by which the formulae and TCHPs achieve this synergism have not been elucidated, and changes to the combinations have rarely been studied. In order to investigate the mechanism of this synergy, six herbs were tested, including Radix Astragali (Astragalus membranaceus (AME)), Radix Paeoniae Alba (Paeonia lactiflora (PL)), Rhizoma Atractylodis Macrocephalae (Atractylodes macrocephala (AMA)), Radix Angelicae Sinensis (Angelica sinensis (AS)), Radix Glycyrrhizae (Glycyrrhiza...

In this article, the compressive residual stress field (CRSF) introduced by shot peening was studied comprehensively. The 40Cr steel, which is widely applied in industry materials, was used and shot peened under different conditions. The experimental results show that the maximum of compressive residual stress field for a given material is almost the same even under different shot peening techniques and the surface residual stress values are dependent on both the mechanical properties of target materials and peening parameters.

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Chemical composition of the essential oils derived from Atractylodes macrocephala (AMA), Astragalus membranaceus (AME) and AMA-AME herb pair was investigated using gas chromatography-mass spectrometry (GC-MS). Antioxidant activities were evaluated by 1,1-diphenyl-2-picyrlhydrazyl (DPPH) radicalscavenging and Trolox equivalent antioxidant capacity (TEAC) assays. Forty-five, ten and forty-three components were identified in AMA, AME and AMA-AME essential oils, respectively. AMA-AME essential oil exhibited a significantly higher radical scavenging capacity than the theoretical sum of those of the respective herb essential oils (P < 0.05). Principal component analysis showed that twenty-three components contributed to the scavenging activities against DPPH and ABTS •+ radicals. Moreover, the concentrations of these major components exhibited various increases to some extent when compared with the theoretical sum of the respective herb essential oils. These findings suggest that combination of two or more herbs might be used as a promising source of natural antioxidants in the pharmaceutical and food industries.