Recently, recycling of rare metals has been of great interest because of the rapid growth in their demands. Substance flow analysis (SFA) is a useful tool to figure out the flow of substance in designated area. SFA is sometimes used to quantify the recycling potentials of the substances. However, few SFA has so far been conducted for rare metals. In this paper, we focused on Dy and conducted SFA of Dy in Japan. The end use of Dy was categorized into 4 groups; automobiles, electronic home appliances, factory automation and voice coil motor, which were further subdivided into 10 categories. We estimated time series data about the domestic consumption and input of Dy in each end use during 1987 2008 in Japan using bottom up approach. Stock in use of Dy was estimated as the recycle potential by using the dynamic SFA, in which the time series data and lifetime distribution of each end use were used. As a result, the stock in use of Dy in Japan was estimated as approximately 890 1100 t in 2008. It was also found that, the amount of domestic input (170 220 t) was half of the amount of import (360 400 t) because a lot of Dy contained in final products were exported from Japan.

The accumulation of waste tires is a global resource and environmental problem. The landfill or incineration of tires will infiltrate toxic chemicals into the surrounding environment, which poses a serious ecological threat to the environment. A large number of studies have shown that waste tires can be used in geotechnical engineering, which provides a good idea for the recycling of waste tires. Up to now, researchers have tested the performance of soil mixed with waste tires by dynamic triaxial test, California load ratio test, unconfined compression test, direct shear test, consolidation test, and expansive force test. The results show that the stability and strength of the soil can be enhanced by adding about 20% rubber particles to the expansive soil, and the expansion, contraction, and consolidation characteristics of the expansive soil can be significantly improved. Rubber can improve the mechanical properties and deformation properties of sand. The rubber sand with a rubber content of 30% is often used as the isolation layer of middle and low buildings. However, it remains to be seen whether it is sustainable and durable to use waste tire rubber to improve soil properties and whether the chemical composition of waste tire rubber will have adverse effects on soil. So, more researchers are encouraged to look into this question. Here, we review the method and effect of rubber reinforcement technology with scrap tires and introduce the practical application of rubber reinforcement technology in engineering, such as specific engineering projects for retaining wall, road filling, shock absorption, and vibration isolation. This review will be of great significance and broad prospects for the reuse of waste tires and the development of geotechnical engineering.

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Matrine (MT) is a major bioactive compound extracted from Sophorae tonkinensis. However, the clinical application of MT is relatively restricted due to its potentially toxic effects, especially hepatotoxicity. Although MT-induced liver injury has been reported, little is known about the underlying molecular mechanisms. In this study, transcriptomics and metabolomics were applied to investigate the hepatotoxicity of MT in mice. The results indicated that liver injury occurred when the administration of MT (30 or 60 mg/kg, i.g) lasted for 2 weeks, including dramatically increased alanine aminotransferase (ALT), aspartate aminotransferase (AST), etc. The metabolomic results revealed that steroid biosynthesis, purine metabolism, glutathione metabolism, and pyruvate metabolism were involved in the occurrence and development of MT-induced hepatotoxicity. Further, the transcriptomic data indicated that the downregulation of NSDHL with CYP51, FDFT1, and DHCR7, involved in steroid biosynthesis, resulted in a lower level of cholic acid. Besides, Gstps and Nat8f1 were related to the disorder of glutathione metabolism, and HMGCS1 could be treated as the marker gene of the development of MT-induced hepatotoxicity. In addition, other metabolites, such as taurine, flavin mononucleotide (FMN), and inosine monophosphate (IMP), also made a contribution to the boosting of MT-induced hepatotoxicity. In this work, our results provide clues for the mechanism investigation of MT-induced hepatotoxicity, and several biomarkers (metabolites and genes) closely related to the liver injury caused by MT are also provided. Meanwhile, new insights into the understanding of the development of MT-induced hepatotoxicity or other monomer-induced hepatotoxicity were also provided.

Expansive soil has a significant impact on the stability of many key construction projects in cold regions. To study the physical and mechanical properties of expanded soil under the condition of freeze-thaw cycle, cryogenic cyclic triaxial tests were conducted on the dynamic and the displacement characteristics of geosynthetic-reinforced expansive soil subjected to the freeze-thaw cycles. Compared with the unreinforced expansive soil samples, the effects of freeze-thaw cycles on the soil dynamics were discussed. The dynamic shear modulus (Gd) and damping ratio (λ) of the expansive soil samples are improved by reinforcement. Reinforced soil can inhibit the axial compression of the sample and restrain the frost heave deformation of the sample during the freezing process. Meanwhile, it can delay the structural damage effect caused by frost heave and reduce the rate of change of the Gd and the λ with the freeze-thaw cycle. At the same time, reinforced soil can inhibit the axial expansion, reduce the rate of reduction of the Gd, stabilize it with a higher rate, and reduce the influence of the freeze-thaw cycles on the λ of the expansive soil sample. Finally, the change of mechanical properties of expansive soil under the condition of reinforcement is obtained. The main conclusions of this paper can be used to reinforce the roadbed and foundation engineering of frozen soil in a cold region and provide support for the fiber reinforcement method of expansive soil.