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Most people are dwelling in cities, which contain a high density of buildings constructed of concrete or similar materials. Conventional grey-colored concrete is absorptive to solar radiation and discharges the absorbed heat to the air as sensible heat, contributing to the development of urban heat island. While existing studies have attempted to find high-reflective concrete by varying the components of the concrete mix, the influence of cured conditions on the albedo of concrete samples is still unknown and has not been reported. Here we first prepared 120 cement pastes with different water-to-cement ratios and different cementitious materials, and then cured the pastes in an indoor environment and a moist chamber, respectively. After cured in a moist chamber for 28 days and then cured in the air for 365 days, the spectral reflectance of all the pastes was tested. Experimental results indicated that the pastes cured in a moist chamber have an albedo that is 0.01–0.10 greater than those of the pastes cured in an indoor environment, with a greater albedo difference at relatively higher water-to-cement ratios. The results also revealed that when concrete productions, such as concrete roof tiles and concrete paver blocks, are prepared, it is practical to cure such productions in a moist environment to get a high albedo.

Obesity is a worldwide problem that resulted from the excessive fat accumulation in adipose tissue, leading to the impairment of individual health. Mulberry leaf is an important traditional Chinese medicine and has been used to alleviate obesity for a long term. However, its underlying molecular mechanisms have not been fully elucidated yet.In this study, we aimed to investigate the inhibition effects of mulberry leaf water extract (MLWE) on lipid accumulation during the process of differentiation of 3T3-L1 preadipocytes and development of mature adipocytes through the combination of molecular biology assays and metabolomic analysis.The quality consistency and main chemical ingredients of MLWE were analyzed by high performance liquid chromatography and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), respectively. Oil red O staining was used to mirror lipid accumulation. Lipogenesis-, lipolysis- and inflammation-related genes were evaluated by real-time PCR and western blot, respectively. Untargeted metabolomics were performed by LC-MS/MS.Prepared method and quality of MLWE were stable and reliable. A total of 34 compounds were identified and 14 of them were undoubtedly confirmed. MLWE supplementation could dose-dependently inhibit the aggregation of lipid droplets, and the expressions of sterol regulatory element-binding protein (SREBP)-1c, peroxisome proliferator-activated receptor (PPAR) γ, acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), tumor necrosis factor (TNF)-α and interleukin (IL)-6, and increase the expressions of adenosine monophosphate-activated protein kinase (AMPK), hormone-sensitive lipase (HSL) and IL-10 in the differentiation of preadipocytes. Furthermore, MLWE treatment could dose-dependently decrease the level of triglycerides and the expressions of ACC, FAS, TNF-α, and IL-6, and up-regulate the level of glycerol and the expressions of PPARα, adiponectin (ADPN), adiponectin receptor (AdipoR) 1, AdipoR2, AMPK, HSL, and IL-10 in the development of mature adipocytes. Untargeted metabolomics showed that a total of 5 and 18 differential metabolites were reversed by MLWE intervention in the differentiation of preadipocytes and the development of mature adipocytes, respectively, which involved in the biosynthesis of unsaturated fatty acids, arachidonic acid metabolism and glycerophospholipids metabolism.Taken together, this study firstly verified that MLWE could effectively alleviate lipid accumulation and inflammation by regulating ADPN/AMPK-mediated signaling pathways and relevant metabolic disturbances including biosynthesis of unsaturated fatty acids, arachidonic acid metabolism and glycerophospholipids metabolism.

Corrosion of steel reinforcement usually causes damage and deterioration of the reinforced concrete. Conventional corrosion experiments or analysis typically focus on the overall corrosion of the entire reinforcing steel bar while the distribution of the corrosion along the rebar has not yet been extensively investigated. In the present study the distribution of corrosive damage was investigated in a series of controlled, accelerated corrosion tests. The acoustic emission (AE) technique was employed to correlate the acoustic emission characteristics to the corrosion along the corroded rebar. A model for the corrosion damage distribution is established based on a Gaussian distribution function. The numerical modeling results match reasonably well with experimental results in almost all corrosion tests.