Surface Settlement Prediction for EPB Shield Tunneling in Sandy Ground

Yongfang Jia,Chuan He,Ali Nazem,Zhigang Yao,Jacob Grasmick 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.7

Ground volume loss induced by shield tunnel construction is the major factor leading to ground settlement and deformation. The general equations predicting surface settlement based on ground volume loss involve a settlement trough width coefficient (parameter i) which in previous models was set as a constant in both the transverse and longitudinal directions. In this work, the equations predicting surface settlement during the construction were modified by introducing the parameter j – the width coefficient in the longitudinal direction, assumed to be different from that in the transverse direction. A model shield machine was adopted to carry a laboratory test under 1 g to investigate surface settlement induced by earth-pressure-balance shield tunnel construction in unsaturated sandy soil. The surface settlement during the excavating observed in the test was compared with that predicted by general equations from previous studies and the modified. The results showed that surface settlement above shield machine obtained by the modified equation proposed here fits the test data better than those obtained by the general equations because of the introduced longitudinal width coefficient.

Liner Behavior of a Tunnel Constructed Below a Caved Zone

Yongfang Jia,Zhigang Yao,Gabriel Walton,Yapeng Fu 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.10

Underground mining leads to deformation of the surrounding rock strata. Over time, this deformation tends to stabilize after mining has completed. However, ground movement can easily reactivated if another adjacent underground project is excavated nearby. When tunnelling underneath caved mining areas, the associated effects on load distribution and liner behavior of this caved zone can be significant. This paper presents a series of scale model tests to understand these effects. In these tests, various testing material compositions were used to simulate intact rocks, a caved zone, primary support and secondary liner based on similarity theory. Various caved zone-tunnel distances (d) and different buried depths were considered in the tests. Results such as deformation, thrust force and bending moment of the liner were recorded and compared. The results show that the caved zone has an obvious impact on the liner when it is located above and nearby the tunnel, but this influence decreases rapidly as a function of d. If the caved zone-tunnel distance is between 50% and 100% of the tunnel span, the bearing capability of the rock immediately surrounding the excavation is significantly reduced, which leads to more vertical load on the support of the tunnel compared to a tunnel without a caved zone. Furthermore, as the shape of broken rock is irregular and the arrangement is random, the caved zone creates an asymmetrical distribution of displacements if the tunnel is near the caved zone. Additionally, this may result in large moments and damage at the tunnel crown.

Differences in the gut microbiota between Cercopithecinae and Colobinae in captivity

Zongjin Huan,Yongfang Yao,Jianqiu Yu,Hongwei Chen,Meirong Li,Chaojun Yang,Bo Zhao,Qingyong Ni,Mingwang Zhang,Meng Xie,Huailiang Xu 한국미생물학회 2020 The journal of microbiology Vol.58 No.5

The gut microbiome of captive primates can provide a window into their health and disease status. The diversity and composition of gut microbiota are influenced by not only host phylogeny, but also host diet. Old World monkeys (Cercopithecidae) are divided into two subfamilies: Cercopithecinae and Colobinae. The diet and physiological digestive features differ between these two subfamilies. Accordingly, highthroughput sequencing was used to examine gut microbiota differences between these two subfamilies, using data from 29 Cercopithecinae individuals and 19 Colobinae individuals raised in captivity. Through a comparative analysis of operational taxonomic units (OTUs), significant differences in the diversity and composition of gut microbiota were observed between Cercopithecinae and Colobinae. In particular, the gut microbiota of captive Old World monkeys clustered strongly by the two subfamilies. The Colobinae microbial diversity was higher than that of Cercopithecinae. Additionally, Firmicutes, Lactobacillaceae, Veillonellaceae, and Prevotella abundance were higher in Cercopithecinae, while Bacteroidetes, Ruminococcaceae, Christensenellaceae, Bacteroidaceae, and Acidaminococcaceae abundance were higher in Colobinae. PICRUSt analysis revealed that the predicted metagenomes of metabolic pathways associated with proteins, carbohydrates, and amino acids were significantly higher in Colobinae. In the context of host phylogeny, these differences between Cercopithecinae and Colobinae could reflect adaptations associated with their respective diets. This well-organized dataset is a valuable resource for future related research on primates and gut microbiota. Moreover, this study may provide useful insight into animal management practices and primate conservation.

Review : Alpha-Ketoglutarate: Physiological Functions and Applications

( Nan Wu ),( Mingyao Yang ),( Uma Gaur ),( Huailiang Xu ),( Yongfang Yao ),( Diyan Li ) 한국응용약물학회 2016 Biomolecules & Therapeutics(구 응용약물학회지) Vol.24 No.1

Alpha-ketoglutarate (AKG) is a key molecule in the Krebs cycle determining the overall rate of the citric acid cycle of the organism. It is a nitrogen scavenger and a source of glutamate and glutamine that stimulates protein synthesis and inhibits protein degradation in muscles. AKG as a precursor of glutamate and glutamine is a central metabolic fuel for cells of the gastrointestinal tract as well. AKG can decrease protein catabolism and increase protein synthesis to enhance bone tissue formation in the skeletal muscles and can be used in clinical applications. In addition to these health benefits, a recent study has shown that AKG can extend the lifespan of adult Caenorhabditis elegans by inhibiting ATP synthase and TOR. AKG not only extends lifespan, but also delays age-related disease. In this review, we will summarize the advances in AKG research field, in the content of its physiological functions and applications.

Alpha-Ketoglutarate: Physiological Functions and Applications

Wu, Nan,Yang, Mingyao,Gaur, Uma,Xu, Huailiang,Yao, Yongfang,Li, Diyan The Korean Society of Applied Pharmacology 2016 Biomolecules & Therapeutics(구 응용약물학회지) Vol.24 No.1

Alpha-ketoglutarate (AKG) is a key molecule in the Krebs cycle determining the overall rate of the citric acid cycle of the organism. It is a nitrogen scavenger and a source of glutamate and glutamine that stimulates protein synthesis and inhibits protein degradation in muscles. AKG as a precursor of glutamate and glutamine is a central metabolic fuel for cells of the gastrointestinal tract as well. AKG can decrease protein catabolism and increase protein synthesis to enhance bone tissue formation in the skeletal muscles and can be used in clinical applications. In addition to these health benefits, a recent study has shown that AKG can extend the lifespan of adult Caenorhabditis elegans by inhibiting ATP synthase and TOR. AKG not only extends lifespan, but also delays age-related disease. In this review, we will summarize the advances in AKG research field, in the content of its physiological functions and applications.

High-efficiency organic solar cells based on a small-molecule donor and a low-bandgap polymer acceptor with strong absorption

Yang, Yankang,Qiu, Beibei,Chen, Shanshan,Zhou, Qiuju,Peng, Ying,Zhang, Zhi-Guo,Yao, Jia,Luo, Zhenghui,Chen, Xiaofeng,Xue, Lingwei,Feng, Liuliu,Yang, Changduk,Li, Yongfang The Royal Society of Chemistry 2018 Journal of materials chemistry. A, Materials for e Vol.6 No.20

<P>Solution-processed organic solar cells (OSCs) have been attracting more and more attention for a series of well-known advantages, and power conversion efficiencies (PCEs) of over 11% have been reported. However, the highest PCE of the OSCs based on small molecule donor/polymer acceptor blends is only 4.82%, which was much lower than those of other types of OSCs due to weak absorption of the polymer acceptor and the unbalanced charge carrier mobility of the small molecule donor and the polymer acceptor. Here, we fabricated small molecule donor/polymer acceptor-based OSCs using the wide bandgap SM1 and DR3TBDTT as the small molecular donor and the low-bandgap n-type conjugated polymer PZ1 as the polymer acceptor. With the treatment of a solvent additive, which can promote the absorption intensity, enhance the carrier mobility and suppress the charge carrier recombination, the SM1-based devices and the DR3TBDTT-based devices show PCEs of 3.97% and 5.86%, respectively. It is worth mentioning that the PCE of 5.86% is the state-of-the-art efficiency for OSCs based on the small molecular donor/polymer acceptor system.</P>

Oviposition preference and offspring performance of Apoderus dimidiatus (Coleoptera: Atelabidae) between Rosa multiflora and Rubus ichangensis

Xie Meng,Du Jinying,Yang Kunqi,Song Shaoting,Lv Zonghui,Xu Huailiang,Wen An Xiang,Wang Qin,Jiang Yanzhi,Zhu Guangxiang,Wu Jiayun,Yao Yongfang,Ni Qingyong 한국곤충학회 2021 Entomological Research Vol.51 No.2

Leaf-rolling weevils (Coleoptera: Atelabidae) are considered to be specialists that oviposit only on one or two plant species. However, Apoderus dimidiatus can oviposit on at least five species. We aimed to determine whether A. dimidiatus females have different preferences for oviposition substrates, and whether differences in physical factors, nutrition and parasitism affected their choices. We observed the number of cradles, hatched larvae, pupae, emerging adults and parasitism rate during one breeding season. Weevils were given access to two host plant species, Rosa multiflora and Rubus ichangensis, and the leaf size and nutrient contents of the two plant species were investigated. We found that nutritional content, especially soluble carbohydrate, correlated with oviposition preference of weevils, and the more nutritious plant species, R. multiflora, was the preferred host in our experiment. Weevils can also use Ru. ichangensis and other plant species as hosts, likely to relieve the high parasitic pressure when laying eggs on a single host species.