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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cell.2008.03.025 Byline: Yi Tang (1), Wenhui Zhao (1), Yue Chen (3), Yingming Zhao (3), Wei Gu (1)(2) Keywords: PROTEINS; SIGNALING Abstract: The activation of the tumor suppressor p53 facilitates the cellular response to genotoxic stress; however, the p53 response can only be executed if its interaction with its inhibitor Mdm2 is abolished. There have been conflicting reports on the question of whether p53 posttranslational modifications, such as phosphorylation or acetylation, are essential or only play a subtle, fine-tuning role in the p53 response. Thus, it remains unclear whether p53 modification is absolutely required for its activation. We have now identified all major acetylation sites of p53. Although unacetylated p53 retains its ability to induce the p53-Mdm2 feedback loop, loss of acetylation completely abolishes p53-dependent growth arrest and apoptosis. Notably, acetylation of p53 abrogates Mdm2-mediated repression by blocking the recruitment of Mdm2 to p53-responsive promoters, which leads to p53 activation independent of its phosphorylation status. Our study identifies p53 acetylation as an indispensable event that destabilizes the p53-Mdm2 interaction and enables the p53-mediated stress response. Author Affiliation: (1) Institute for Cancer Genetics, College of Physicians & Surgeons, Columbia University, New York, NY 10032, USA (2) Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, New York, NY 10032, USA (3) Department of Biochemistry, UT Southwestern Medical Center Dallas, TX 75390, USA Article History: Received 9 August 2007; Revised 24 December 2007; Accepted 14 March 2008 Article Note: (miscellaneous) Published: May 15, 2008

The hydrophobic nature of dioxins is a major obstacle to their bioremediation. The present study attempted to improve the bioaccessibility of dioxins in two-phase partitioning bioreactors and activated sludge reactors. Dibenzofuran and n -hexadecane were used as model compounds for dioxins and non-aqueous phase liquids (NAPLs), respectively. First, biosurfactants produced by dioxin-degrading Rhodococcus sp. strain p52 were analyzed. Then, the role of n -hexadecane during the biodegradation of dibenzofuran was evaluated. The results showed that high NAPL ratios (n -hexadecane ≥40 g/L) in the two liquid-phase systems favored dibenzofuran removal, while the cell surface of strain p52 became extremely hydrophobic (>97%), which promoted its adhesion to NAPLs and subsequent transport of dibenzofuran from NAPL to the cells. In addition, a bioaugmented activated sludge reactor with n -hexadecane as the supplemented carbon source could not only facilitate the aerobic granular sludge formation but also improve dibenzofuran removal and the activated sludge settling properties. Simultaneously, conjugative transfer of catabolic plasmids was promoted. This study demonstrated the potential application of strain p52 with NAPLs for the bioremediation of dioxins. [Display omitted] • Strain p52 can produce biosurfactants containing trehalolipids and fatty acids. • n -hexadecane enhanced dibenzofuran removal by strain p52. • Aerobic granules formed in bioaugmented reactor supplemented with n -hexadecane. • n -hexadecane facilitated the transfer of catabolic plasmids in the reactor. [ABSTRACT FROM AUTHOR]

Making environmental impact assessment (EIA) is extremely vital to the green development of pumped hydro energy storage plants (PHESPs). But, three critical issues have not been addressed. First, some key environmental factors having big influences on PHESP have not been identified and evaluated. Second, massive of information loss and distortion exist in current research. Third, there is a lack of a systematic and clear framework for EIA of PHESP. To handle the above three problems and make EIA of PHESP more reasonable, innovations are made from the following aspects: first, to fully reflect environmental characteristics of PHESP, a comprehensive and rational EIA evaluation criteria system including four criteria is built. Second, a group decision-making model is proposed by combining uncertain linguistic variables (ULVs), triangular fuzzy number (TFN) and TODIM (an acronym in Portuguese of interactive and multiple attribute decision making), this model can effectively reduce information loss and distortion. Third, an integrated decision-making framework is constructed from the perspective of system science, this framework can make EIA easy and efficient. Besides, a case study is employed to validate the practicability and effectiveness of the improvements made above. The results show that the proposed framework is of great use for performing EIA of PHESP, and PHESP A 1 performs best among the four alternatives in the environmental aspect. Meanwhile, sensitivity analysis shows that the ranking of four alternatives is very stable; comparative analysis proves that the proposed model is more effective than fuzzy Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) method in reflecting gaps among four alternatives, because its standard deviation 0.360 is bigger than the standard deviation 0.153 gotten by the fuzzy TOPSIS method. Finally, some valuable managerial implications are put forward to the project managers to guide the practical work. • An evaluation criteria system is established for EIA of PHESP. • The TODIM-based group decision model can reduce information loss and distortion. • The integrated framework proposed has good practicability and effectiveness. [ABSTRACT FROM AUTHOR]

Abstract In China, high-speed rails are often constructed over bridges in the region of soft soils. Differential settlement could occur in the foundation soils between bridge abutment and approach embankment that causes "bumps" to affect the smoothness at the end of a bridge. A three-dimensional finite element model is developed to investigate the use of fibre reinforced lightweight concrete in the transition zone of bridge approach for high-speed railways. Time-frequency analysis is performed using the method of Fast Fourier transform. The sensitivity analysis of rail speed, density of backfills, and the structural type of the trapezoidal shaped transition zone is conducted. [ABSTRACT FROM AUTHOR]

The association of estimated glomerular filtration rate (GFR) with cardiovascular disease risk among patients with type 2 diabetes is unclear. Here we prospectively investigated the race-specific association of estimated GFR with the risk of coronary heart disease and stroke among 11,940 Caucasian and 16,451 African-American patients. During mean follow-up of 6.1-6.8 years, 6647 coronary heart disease and 2750 stroke incident cases were identified. Age- and sex-adjusted hazard ratios of coronary heart disease associated with baseline estimated GFR (90 or more, 75-89, 60-74, 30-59, and 15-29 ml/min per 1.73 m2) were 1.00, 1.04, 1.13, 1.37, and 2.07 (significant trend) for African Americans, and 1.00, 1.09, 1.10, 1.31, and 2.18 (significant trend) for Caucasians, respectively. A significantly increased stroke risk was observed among both African-American and Caucasian participants with an estimated GFR under 60 ml/min per 1.73 m2. When using the updated mean values of estimated GFR, these significant associations became stronger. Participants with mildly decreased estimated GFR (60-89 ml/min per 1.73 m2) during follow-up were also at a significantly higher risk of coronary heart disease and stroke. Thus, even mildly reduced estimated GFR at baseline (under 75 ml/min per 1.73 m2) and during follow-up (under 90 ml/min per 1.73 m2) increased the risk of incident coronary heart disease and stroke among both African-American and Caucasian type 2 diabetes patients. [ABSTRACT FROM AUTHOR]

It has been proved that top-down governance alone has limitations in the process of air pollution control, and public participation plays an important role in promoting air pollution governance. However, whether the public awareness of participating in haze governance can be guided by government and the guiding mechanism are still unclear. This paper is based on data from a leading Chinese social media—— Sina Weibo. Over 10.54 million haze-related blogs from 2013 to 2017 have been excavated. Based on the latent Dirichlet allocation (LDA) topic model, the characteristics and evolutionary path of the government and public concern have been analyzed. Furthermore, the empirical results indicate the following. (1) The government has a significant role in promoting the public concern about participating in haze governance. (2) Regional heterogeneity, especially regions with underdeveloped economies, low levels of education and aging populations should receive special attention. (3) The effect of the government is not all-round, "haze governance" and "public participation" have significant impacts on the public concern regarding "participating in haze governance". (4) Media and government have a reciprocal relationship in terms of attracting public attention to haze governance. They are vying for people's limited attention. (5) There are spatial spillover effects of local government. Finally, policy implications and the fairness of online promotion and reflection on the public are discussed. [ABSTRACT FROM AUTHOR]