Oxidative stress in Parkinson’s disease

Oxidative stress contributes to the cascade, leading to dopamine cell degeneration in Parkinson’s disease. However, oxidative stress is intimately linked to other components of the degenerative process, such as mitochondrial dysfunction, excitotoxicity, nitric oxide toxicity and inflammation. It is therefore difficult to determine whether oxidative stress leads to or is a consequence of, these events. Oxidative stress was assessed by estimating lipid peroxidation product in the form of thiobarbituric acid reactive substances, nitric oxide in the form of nitrite & nitrate. Enzymatic antioxidants in the form of superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin and non enzymatic antioxidant vitamins e.g. vitamin E and C in either serum or plasma or erythrocyte in 40 patients of Parkinson’s disease in the age group 40–80 years. Trace elements e.g. copper, zinc and selenium were also estimated. Plasma thiobarbituric acid reactive substances and nitric oxide levels were Significantly high but superoxide dismutase, glutathione peroxidase, catalase, ceruloplasmin, vitamin-E, vitamin-C, copper, zinc and selenium levels were significantly low in Parkinson’s disease when compared with control subjects. Present study showed that elevated oxidative stress may be playing a role in dopaminergic neuronal loss in substentia nigra pars compacta and involved in pathogenesis of the Parkinson’s disease.     

China’s Largest Science Facility in Operation

The Shanghai Synchrotron Radiation Facility (SSRF), a third-generation of synchrotron radiation light source, has opened its door to users recently.     

CAS in China’s Lunar Exploration Program

<正>The Chinese Academy of Sciences (CAS) is among the initiators of the China Lunar Exploration Program (CLEP), and has directly contributed to this grand program.The Academy proposed the scientific goals of the program;as a coorganizer and important contributor, it has overseen its implementation to secure the fulfillment of the presetgoals, providing strong S&T support.     

Asymptotic properties of Spearman’s footrule and Gini’s gamma in bivariate normal model

This paper aims at rejuvenating the two rank correlation coefficients, Spearman’s footrule (SF) and Gini’s gamma (GG), which were forgotten in the literature for a long time due to lack of knowledge concerning their statistical properties. Under the common bivariate normal model, we establish the asymptotic analytical expressions of the mean and variance of SF and GG, and investigate the performances of SF and GG from the aspects of biased effect, approximate variance and asymptotic relative efficiency (ARE). Moreover, we further study the robustness of SF and GG under contaminated normal models. In order to get a deeper understanding of their performances, we also compare SF and GG with Kendall’s tau (KT) and Spearman’s rho (SR), the most widely used rank correlation coefficients, in terms of bias and mean square error (MSE) under both the normal and contaminated normal models. Finally we show an application of SF and GG in the field of signal processing through the example of time-delay estimation. Simulation results indicate that SF and GG outperform SR and KT in some cases. The new findings discovered in this paper enable SF and GG to play complementary roles to KT and SR in practice.     

China’s first Australian Garden opens in Guangzhou

The opening for the Australian Garden was jointly held by the BHP Billiton China and the CAS South China Botanical Garden (SCBG) in Guangzhou, capital of south China's Guangdong Province on 18 January. Those present at the ceremony included Prof. Andrew Smith and Prof. Sue Serjeantson from the Australian Academy of Science, Prof. Dave Paterson from the Royal Botanic Garden in Edinburgh, and representatives from the CAS Headquarters, CAS Guangzhou Branch, PHB Billiton China and SCBG.