Acreditación de la educación superior en China

La creciente preocupación por la calidad de la educación superior en China surgió como una consecuencia natural de la expansión de la educación superior, que empezó en 1999 y ha continuado hasta la fecha; la tasa bruta de matrícula aumentó considerablemente, desde el 9,8 % en 1998 hasta el 21 % en 2005. El número total de estudiantes matriculados en el sistema de educación superior chino en 2005 superó los 23 millones. La multiplicación por dos de la matrícula a lo largo de los últimos siete años convierte al sistema chino de educación superior en el mayor sistema nacional del mundo.Peer Reviewe

Chinese Herbal Medicine as an Adjunctive Therapy for Breast Cancer: A Systematic Review and Meta-Analysis

Chinese herbal medicine (CHM) has been widely used as an adjunctive therapy for breast cancer, while its efficacy remains unexplored. The purpose of this study is to evaluate the efficacy of CHM combined with chemotherapy for breast cancer. The study results showed that CHM combined with chemotherapy significantly increased tumor response and KPS as compared to using chemotherapy alone (RR = 1.36; 95% CI = 1.24–1.48; P<0.00001; RR = 1.38; 95% CI = 1.26–1.52; P<0.00001, resp.). Besides, CHM as an adjunctive therapy significantly reduced the nausea and vomiting at toxicity grade of III–IV (RR = 0.37; 95% CI = 0.27–0.52; P<0.00001). Moreover, the combined therapy significantly prevented the decline of WBC in patients under chemotherapy at toxicity grade of III–IV (RR = 0.49; 95% CI = 0.34–0.69; P<0.00001) and prevented the decline of platelet at toxicity grade of III–IV or I–IV (RR = 0.29; 95% CI = 0.12–0.73; P=0.008; RR = 0.77; 95% CI = 0.63–0.94; P=0.009, resp.). This study suggests that CHM combined with chemotherapy in comparison with chemotherapy alone can significantly enhance tumor response, improve KPS, and alleviate toxicity induced by chemotherapy in breast cancer patients. However, a firm conclusion could not be reached due to the lack of high quality trials and large-scale RCTs, so further trials with higher quality and larger scale are needed

Anonymous and Efficient Message Authentication Scheme for Smart Grid

Smart grid has emerged as the next-generation electricity grid with power flow optimization and high power quality. Smart grid technologies have attracted the attention of industry and academia in the last few years. However, the tradeoff between security and efficiency remains a challenge in the practical deployment of the smart grid. Most recently, Li et al. proposed a lightweight message authentication scheme with user anonymity and claimed that their scheme is provably secure. But we found that their scheme fails to achieve mutual authentication and mitigate some typical attacks (e.g., impersonation attack, denial of service attack) in the smart grid environment. To address these drawbacks, we present a new message authentication scheme with reasonable efficiency. Security and performance analysis results show that the proposed scheme can satisfy the security and lightweight requirements of practical implementations and deployments of the smart grid

Rietveld Structure Refinement of Cu-Trien Exchanged Nontronites

The Rietveld analysis of X-ray powder diffraction patterns is used widely for obtaining the structural information of clay minerals. However, the complex hydration behavior and the variability of interlayer contents are often considered difficult to be described correctly by a simple structure model. In the present work, the use of Cu-triethylenetetramine (Cu-trien)-exchanged nontronites has been proposed to simplify the interlayer structure. This method provides a potential to obtain the structural information of nontronites, for example, the layer charge density, occupancies of cis-octahedral sites, and the iron content by the Rietveld analysis from the X-ray powder diffraction patterns. The approach was demonstrated on three Cu-trien-exchanged nontronite samples. The Rietveld refinements were carried out first on the purified samples and the results showed a good peak fitting between measured and calculated patterns. The refined iron content and the occupancies of cis-octahedral sites are in general agreement with the reference data, which have been obtained from chemical and thermal analyses. The refinement of layer charge density showed lower values compared with the reference. It may be due to the assumption of temperature factor of Cu-trien in the interlayer. A raw sample with natural impurities was chosen to test the applicability of this method. The refinement pattern of the raw sample led to good agreement with the observed data. The results of the iron content and the occupancies of cis-octahedral sites showed the same tendency as purified samples. This study showed that this approach allows for obtaining some structural details of nontronites directly from X-ray powder diffraction patterns of Cu-trien-exchanged samples

Environmental Factors Influencing the Durability of Concrete Structures in Maine Environments

Concrete structures built in marine environment may suffer serious durability problems. Focusing on the reaction between concrete materials and environmental conditions on structural durability, the coefficients of environmental temperature and chloride content are established. Referring to only experimental data tested following the procedure similar to the regulations in NT Build 443(Concrete, Hardened: Accelerated Chloride Penetration) of North Europe, the relationship between D28 and water/binder ratio, which are converted into equivalent values of a standard reference environmental condition at 20ºC and a concentration of 165 g ± 1 g NaCl per dm3 solution, using the established formula of coefficients of environmental temperature and chloride content, is presented. The converted results of different environmental conditions at laboratory and natural environment have a good agreement with each other, which indicates that the coefficients of environmental temperature and chloride content are reasonably determined. The ratio of wetting time per-period defined as the time proportion of concrete in wet conditions to the whole time period can be used to describe the dry-wet conditions in concrete. Analysis on the in-situ detected results shows that the penetration of chloride, the accumulation of surface chloride concentration and the decay of chloride diffusion coefficient are all related to the ratio of wetting time per-period. Subsequently, the formula of apparent chloride diffusion coefficient is proposed with consideration of surrounding temperature, sodium chloride solution concentration, age factor and altitude