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Geocell is one of the geosynthetic products used primarily for soil reinforcement. It was originally developed by US Army Corps of Engineers in 1970s for quick reinforcement of cohesionless soil in the military field. Due to its unique three-dimensional geometry, geocell can provide great lateral confinement to the infill soil without relying on the interlocking or friction with the infill soil. Despite the successful applications in various types of civil engineering projects, the mechanism of geocell reinforcement has not been well understood, especially for load-supporting applications. In this study, laboratory model tests (including static load tests and moving wheel load tests) were performed to characterize the performance of the geocell-reinforced soil. A total of four types of geocell (manufactured by PRS Mediterranean, Inc.) were tested in this study. One was made from conventional high density polyethylene (HDPE) and the other three were made from novel polymer alloy (NPA). NPA is a new material characterized by flexibility at low temperatures similar to HDPE with elastic behavior similar to engineering thermoplastic. Test result showed that geocell products tested in this study can improve the modulus and strength of the granular soil under static load, as well as reduce the permanent deformation of the unpaved road under moving wheel loads. Three-dimensional numerical models were developed in this study to simulate the behavior of geocell-reinforced soil under static and repeated loads. In the model for static loading, the infill soil is modeled using a non-linear elastoplastic model (also known as the Duncan-Chang model), and the geocell was modeled using linear elastic plate model. A mechanistic-empirical model was developed for NPA geocell-reinforced soil under repeated loads. This model was developed based on the stress-dependent response model in the current mechanistic-empirical pavement design guide (MEPDG). Some modifications were made to consider (a) the three-dimensional constitutive ...

AbstractCOVID‐19 poses an unprecedented challenge to human society. To cope with the pandemic, people seek information from various communication channels. Microblog websites are highly influential information channels for the public to get timely information during the pandemic. Building on the heuristic‐systematic processing model, this study identifies the multiple characteristics (content, author, and social features) that may play a role in triggering long cascades of reposts of COVID‐19‐related news microblogs. With a large‐scale news microblog database collected from Weibo and an innovative information gain method, we find that heuristic thinking plays a dominant role in COVID‐19 pandemic‐related news microblog reposting decisions and further discloses the specific influencing factors of such behavior.

AbstractManuscript TypeEmpiricalResearch Question/IssuePrior studies on the role of state investment tend to focus on either majority state ownership or aggregating majority and minority state ownership. Drawing upon signaling theory, we theorize that the negative intent signaled by minority state ownership reduces initial public offering (IPO) market performance. In addition, we hypothesize that founders as chief executive officers and outside directors not from state‐owned enterprises, representing the positive signal of intent, can attenuate the negative effect of minority state ownership.Research Findings/InsightsThe empirical results, based on 274 small and private firms in China's newly launched stock market, provide support for the hypotheses based on price premium, first‐day turnover rate, first‐day price increase, underpricing, and Tobin's Q.Theoretical/Academic ImplicationsTo the best of our knowledge, this is the first study to examine how minority state ownership affects small and private firm IPO performance. It suggests new avenues of research on ownership structure and the principal‐principal problem in the corporate governance of emerging economies. This study reveals the distinctive nature and effect between controlling state ownership and minority state ownership. The current research also opens new avenues of research on applying signaling theory, signal of intent in particular, in an IPO study.Practitioner/Policy ImplicationsThis study reveals the negative intent signaled by minority state ownership in privately controlled firms at IPO due to the weak monitoring capacity, limited resource provision, and enhanced political interdependency between private controllers and minority state owners. As minority state ownership becomes a more salient phenomenon in emerging markets, it guides policy makers in governance choices for government‐funded firms.

Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a potent AhR ligand, is an environmental contaminant that is known for mediating toxicity across generations. However, whether TCDD can induce multigenerational changes in the expression of microRNAs (miRs) has not been previously studied. In the current study, we investigated the effect of administration of TCDD in pregnant mice (F0) on gestational day 14, on the expression of miRs in the thymus of F0 and subsequent generations (F1 and F2). Of the 3200 miRs screened, 160 miRs were dysregulated similarly in F0, F1, and F2 generations, while 46 miRs were differentially altered in F0 to F2 generations. Pathway analysis revealed that the changes in miR signature profile mediated by TCDD affected the genes that regulate cell signaling, apoptosis, thymic atrophy, cancer, immunosuppression, and other physiological pathways. A significant number of miRs that showed altered expression exhibited dioxin response elements (DRE) on their promoters. Focusing on one such miR, namely miR-203 that expressed DREs and was induced across F0 to F2 by TCDD, promoter analysis showed that one of the DREs expressed by miR-203 was functional to TCDD-mediated upregulation. Also, the histone methylation status of H3K4me3 in the miR-203 promoter was significantly increased near the transcriptional start site in TCDD-treated thymocytes across F0 to F2 generations. Genome-wide chromatin immunoprecipitation sequencing study suggested that TCDD may cause alterations in histone methylation in certain genes across the three generations. Together, the current study demonstrates that gestational exposure to TCDD can alter the expression of miRs in F0 through direct activation of DREs as well as across F0, F1, and F2 generations through epigenetic pathways.

Taxol, a natural product derived from Taxus, is one of the most effective natural anticancer drugs and the biosynthetic pathway of Taxol is the basis of heterologous bio-production. Here, we report a high-quality genome assembly and annotation of Taxus yunnanensis based on 10.7 Gb sequences assembled into 12 chromosomes with contig N50 and scaffold N50 of 2.89 Mb and 966.80 Mb, respectively. Phylogenomic analyses show that T. yunnanensis is most closely related to Sequoiadendron giganteum among the sampled taxa, with an estimated divergence time of 133.4−213.0 MYA. As with most gymnosperms, and unlike most angiosperms, there is no evidence of a recent whole-genome duplication in T. yunnanensis. Repetitive sequences, especially long terminal repeat retrotransposons, are prevalent in the T. yunnanensis genome, contributing to its large genome size. We further integrated genomic and transcriptomic data to unveil clusters of genes involved in Taxol synthesis, located on the chromosome 12, while gene families encoding hydroxylase in the Taxol pathway exhibited significant expansion. Our study contributes to the further elucidation of gymnosperm relationships and the Taxol biosynthetic pathway. ; The National Key R&D Program of China from the Ministry of Science and Technology of China, the National Natural Science Foundation of China and Karst Science Research Center of Guizhou Province; Scientific and technological innovation project of China Academy of Chinese Medical Sciences; National Key Research and Development Project and National Natural Science Foundation of China; the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program and Ghent University. ; https://www.nature.com/commsbio ; am2022 ; Biochemistry ; Genetics ; Microbiology and Plant Pathology