Coefficient of Restitution and Kinetic Energy Loss of Rockfall Impacts

Li-Ping Li,Shang-qu Sun,Shucai Li,Qian-qing Zhang,Cong Hu,Shao-shuai Shi 대한토목학회 2016 KSCE JOURNAL OF CIVIL ENGINEERING Vol.20 No.6

This paper presents the results of the coefficient of restitution and the kinetic energy loss rate obtained by lab experiment, two parameters that are crucial for rockfall impact. However, various definitions of coefficient of restitution exist and the most appropriate one is still not formed and obtained. In addition, the energy variation during the rockfall impacts has important significance in practical design. In this research, two kind shapes of blocks including plate and strip were adopted in the laboratory testing and the block material was tested before, indicating that the material has sufficient strength to prevent shattering during the impact. Furthermore, an apparatus specifically built for this study was established including a base, a slope and a releasing device. The falling testing was performed using plate and strip block while the falling height as well as the slope angle and releasing height were altered during the tests in order to estimate the effect of each parameter on the coefficients of restitution and energy loss rate. It was observed that collision reflection angle is less than impact angle for all, suggesting energy loss in collision. Impact angle decreases with increasing slope angle while there was no obvious effect of releasing height and releasing angle on impact angle. The relevant coefficient of restitution was found to decrease with impact angle, and the kinetic energy loss rate increased. Finally, the kinetic energy before and after the impact was found to significantly affect the COR and energy loss rate and the results can provide basis for mitigation measures.

Molecule-based electrorheological material assembled using β-cyclodextrin as substrate

Yan-Li Shang,Yun-Ling Jia,Yun Ma,Jun-Ran Li,Shao-Hua Zhang,Ming-Xiu Li 한국유변학회 2010 Korea-Australia rheology journal Vol.22 No.1

Molecule-based electrorheological (ER) materials as a novel type of ER materials, the inclusion compound [H2(β-CD-A)-PTA] between p-toluenesulfonic acid (PTA, guest) and H2(β-CD-A) (host) that is dicarboxylic acid of β-cyclodextrin (β-CD) , and the rare earth (RE) complexes [(β-CD-A)-PTA]3RE2 (RE=La, Gd, Y)of H2(β-CD-A)-PTA, were synthesized. The ER performance and dielectric property of the materials were studied. Our results show that the molecule-based ER materials assembled using β-cyclodextrin as a substrate,especially the inclusion compound and its rare earth (RE) complexes exhibit clear ER effect. The inclusion PTA can markedly enhance the ER performance of H2(β-CD-A) material. The ER activity of the yttrium complex is the highest among these materials. The characteristic of the molecule in molecule-based ER materials is an important factor in influencing ER property.

Hypoglycemic and Hypolipidemic Activity of Polygonatum sibiricum Fermented with Lactobacillus brevis YM 1301 in Diabetic C57BL/6 Mice

Caiyun Li,Jixia Li,Yaxian Shang,Yao Wang,Jingru Gao,Nan Xue,Chunying Huang,Farong Li,Jia Li 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.7

Polygonatum sibiricum (PS) has been used as herbal medicine to treat type 2 diabetes mellitus (T2DM). However, how lactic acid fermentation of PS influences glucose and lipid metabolism remains unclear. The current study was undertaken to evaluate the hypoglycemic and hypolipidemic effects of PS fermented with Lactobacillus brevis YM 1301 (YM 1301) in streptozotocin and high-fat diet-induced T2DM mice. Biochemical analysis revealed that supplementation with metformin, PS, or fermented Polygonatum sibiricum (FPS) lowered the fasting blood glucose, insulin, total cholesterol, triglyceride, and low-density lipoprotein cholesterol of diabetic mice. FPS showed relatively more potency to reduce the homeostasis model assessment-insulin resistance and glycated hemoglobin than PS. Moreover, a high dosage of FPS protected against glucose intolerance and insulin resistance by increasing the ratio of phosphor-AKT/AKT. Histological examination and quantitative polymerase chain reaction results showed that dietary FPS ameliorated the lipid accumulation in liver and white adipose tissue (WAT) by inhibiting lipogenesis, enhancing lipolysis, and fatty acid oxidation. FPS exhibited greater efficacy than PS on improving the transcriptional expression of adipose triacylglyceride lipase, carnitine palmitoyltransferase 1, and uncoupling protein 1. In addition, FPS exerted a striking anti-inflammatory effect by suppressing the expression of interleukin 6, interleukin 1β, tumor necrosis factor-α, and transforming growth factor-β in WAT of diabetic C57BL/6 mice. Finally, FPS supplementation enhanced the activation of AMPK. In conclusion, these results suggest that the FPS may be more promising than PS as a potential therapeutic agent for diabetes and obesity.

Luteolin inhibits H2O2-induced cellular senescence via modulation of SIRT1 and p53

Ri Zhe Zhu Bing Si Li Shang Shang Gao Jae Ho Seo Byung-Min Choi 대한생리학회-대한약리학회 2021 The Korean Journal of Physiology & Pharmacology Vol.25 No.4

Luteolin, a sort of flavonoid, has been reported to be involved in neu-roprotective function via suppression of neuroinflammation. In this study, we in-vestigated the protective effect of luteolin against oxidative stress-induced cellular senescence and its molecular mechanism using hydrogen peroxide (H2O2)-induced cellular senescence model in House Ear Institute-Organ of Corti 1 cells (HEI-OC1). Our results showed that luteolin attenuated senescent phenotypes including alterations of morphology, cell proliferation, senescence-associated β-galactosidase expression, DNA damage, as well as related molecules expression such as p53 and p21 in the oxidant challenged model. Interestingly, we found that luteolin induces expression of sirtuin 1 in dose- and time-dependent manners and it has protective role against H2O2-induced cellular senescence by upregulation of sirtuin 1 (SIRT1). In contrast, the inhibitory effect of luteolin on cellular senescence under oxidative stress was abolished by silencing of SIRT1. This study indicates that luteolin effectively protects against oxidative stress-induced cellular senescence through p53 and SIRT1. These results suggest that luteolin possesses therapeutic potentials against age-related hearing loss that are induced by oxidative stress.

Clinicopathologic Characteristics and Prognoses for Multicentric Occurrence and Intrahepatic Metastasis in Synchronous Multinodular Hepatocellular Carcinoma Patients

Li, Shi-Lai,Su, Ming,Peng, Tao,Xiao, Kai-Yin,Shang, Li-Ming,Xu, Bang-Hao,Su, Zhi-Xiong,Ye, Xin-Ping,Peng, Ning,Qin, Quan-Lin,Chen, De-Feng,Chen, Jie,Li, Le-Qun Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Background: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and the outcomes for patients are still poor. It is important to determine the original type of synchronous multinodular HCC for preoperative assessment and the choice of treatment therapy as well as for the prediction of prognosis after treatment. Aims: To analyze clinicopathologic characteristics and prognoses in patients with multicentric occurrence (MO) and intrahepatic metastasis (IM) of synchronous multinodular hepatocellular carcinoma (HCC). Methods: The study group comprised 42 multinodular HCC patients with a total of 112 nodules. The control group comprised 20 HCC patients with 16 single nodular HCC cases and 4 HCC cases with a portal vein tumor emboli. The mitochondrial DNA (mtDNA) D-loop region was sequenced, and the patients of the study group were categorized as MO or IM based on the sequence variations. Univariate and multivariate analyses were used to determine the important clinicopathologic characteristics in the two groups. Results: In the study group, 20 cases were categorized as MO, and 22 as IM, whereas all 20 cases in the control group were characterized as IM. Several factors significantly differed between the IM and MO patients, including hepatitis B e antigen (HBeAg), cumulative tumor size, tumor nodule location, cirrhosis, portal vein and/or microvascular tumor embolus and the histological grade of the primary nodule. Multivariate analysis further demonstrated that cirrhosis and portal vein and/or microvascular tumor thrombus were independent factors differentiating between IM and MO patients. The tumor-free survival time of the MO subjects was significantly longer than that of the IM subjects ($25.7{\pm}4.8$ months vs. $8.9{\pm}3.1$ months, p=0.017). Similarly, the overall survival time of the MO subjects was longer ($31.6{\pm}5.3$ months vs. $15.4{\pm}3.4$ months, p=0.024). The multivariate analysis further demonstrated that the original type (p=0.035) and Child-Pugh grade (p<0.001) were independent predictors of tumor-free survival time. Cirrhosis (p=0.011), original type (p=0.034) and Child-Pugh grade (p<0.001) were independent predictors of overall survival time. Conclusions: HBeAg, cumulative tumor size, tumor nodule location, cirrhosis, portal vein and/or microvascular tumor embolus and histological grade of the primary nodule are important factors for differentiating IM and MO. MO HCC patients might have a favorable outcome compared with IM patients.

Analysis and Prediction of Structural Plane Connectivity in Tunnel based on Digitalizing Image

Shang-qu Sun,Li-Ping Li,Jing Wang,Hong-liang Liu,Zhongdong Fang,Xingzhi Ba 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.6

The identification of structural plane connectivity is an application problem in rock mass engineering. Theoretically, information of exposed rock mass and its internal borehole is of great significance to predict network of unexcavated rock structural plane, especially in tunnel engineering. In this paper, parameters of structural planes have been obtained through borehole imaging in advance drilling borehole of tunnel face. Furthermore, a geometric discrimination method for the multiple structural plane based on the included angle has been proposed. And then, spatial distribution of the large scale structural plane in the unexcavated rock mass has been recognized by effective assistant techniques. To verify this method, the binocular photogrammetry method has been adopted to investigate the parameters of structural planes during excavation, and then the structural plane model of tunnel face has been constructed. The tunnel face mapping has been compared with that of section of the predicted model. The results showed that included angle identification method based on three boreholes is highly reliable and can be used to accurately construct the deterministic structural plane network in front of the tunnel face.

Characterization and function of a short peptidoglycan recognition protein from the Chinese oak silkworm, Antheraea pernyi

Li-Shang Dai,Cen Qian, LeiWang,Guo-Qing Wei,Qiu-Ning Liu,Yu Sun,Cong-Fen Zhang,Jun Li,Dong-Ran Liu,Bao-Jian Zhu,Chao-Liang Liu 한국응용곤충학회 2015 Journal of Asia-Pacific Entomology Vol.18 No.4

Peptidoglycan recognition proteins (PGRPs) are conserved proteins in animals from insects to mammals and play an important role in immune response by recognizing peptidoglycan on microbial surfaces. In this study, a PGRP gene from Antheraea pernyi, named Ap-PGRP-A, was isolated and characterized. Sequence analysis revealed that the full-length cDNA of Ap-PGRP-A was 961 bp, containing a 40 bp 5′-untranslated sequence, a 339 bp 3′-untranslated region and an open reading frame of 582 bp. This gene encoded a putative protein of 193 amino acid residues. Phylogenetic analysis indicated that Ap-PGRP-A had the closest protein sequence similarity to Antheraea mylitta PGRP. The recombinant protein was successfully expressed in Escherichia coli cells and a rabbit anti-Ap-PGRP-A antibody was also prepared. Real-time quantitative reverse transcription-PCR analysis showed that Ap-PGRP-A was extensively expressed in the fat body, midgut, hemocyte,malpighian tubule and epidermis of A. pernyi, especially in the fat body and midgut. The expression levels of Ap-PGRP-A were significantly up-regulated by three types of microorganisms, and Ap-PGRP-A expression was more sensitive in response to the Gram-negative bacterium E. coli than the Gram-positive bacterium Bacillus subtilis or the fungus Beauveria bassiana. These data indicate that Ap-PGRP-A may play a role in the innate immune responses of A. pernyi.

Association of CAST Gene Polymorphisms with Carcass and Meat Quality Traits in Chinese Commercial Cattle Herds

Li, Jiao,Zhang, Lu-Pei,Gan, Qian-Fu,Li, Jun-Ya,Gao, Hui-Jiang,Yuan, Zheng-Rong,Gao, Xue,Chen, Jin-Bao,Xu, Shang-Zhong Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.11

Calpastatin (CAST), an endogenous inhibitor of the calpains, plays an important role in post-mortem tenderization of meat. The objectives of this study were to investigate single nucleotide polymorphisms (SNPs) in the bovine CAST gene and association with carcass and meat quality traits. A total of 212 cattle from commercial herds were tested in this study including 2 pure introduced breeds, 4 cross populations, and 3 pure Chinese native breeds. Five SNPs were identified at position 2959 (A/G), 2870 (G/A), 3088 (C/T), 3029 (G/A) and 2857 (C/T) in the CAST gene (GenBank Accession No. AF159246). Allele frequencies of SNP2959 and SNP2870 were 0.701 (A) and 0.462 (A), respectively. A general linear model was used to evaluate the associations between the two markers and 7 traits. The results showed that both SNP2959 and SNP2870 were significantly (p<0.01) associated with the Warner-Bratzler shear force (WBSF), while they had no significant association with the other 6 traits in the whole population. However, in Chinese native pure breeds, only SNP2870 had significant association with WBSF (p<0.05). The simultaneous analysis of two-marker genotype effects indicated animals containing the A/G haplotype (A for SNP2959 and G for SNP2870) tended to have lower shear force than those containing the G/A haplotype, and, especially, animals homozygous for the A/G haplotype had approximately 2 kg lower shear force than those homozygous for the G/A haplotype (p<0.01). These results suggested that both markers may be effective for the marker-assisted selection of meat quality traits in Chinese commercial herds, especially SNP2870 which can be used for Chinese native cattle.

Cloning, Expression, and Characterization of a Cold-Adapted and Surfactant-Stable Alginate Lyase from Marine Bacterium Agarivorans sp. L11

( Shang Yong Li ),( Xue Mei Yang ),( Lan Zhang ),( Wen Gong Yu ),( Feng Han ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.5

The purpose of this study was to find a cold-adapted and surfactant-stable alginate lyase as a candidate for biotechnological and industrial applications. The gene for a new alginate lyase, AlyL1, from Agarivorans sp. L11 was cloned and expressed in Escherichia coli. The recombinant AlyL1 was most active at 40ºC (1,370 U/mg). It was a cold-adapted alginate lyase, which showed 54.5% and 72.1% of maximum activity at 15ºC and 20ºC, respectively. AlyL1 was an alkaliphilic enzyme and most active at pH 8.6. In addition, it showed high stability in the presence of various surfactants at a high concentration (from 0.1% to 1% (w/v)). AlyL1 was an endo-type alginate lyase that degraded both polyM and polyG blocks, yielding disaccharides and trisaccharides as the main products. This is the first report of the cloning and functional expression of a cold-adapted and surfactant-stable alginate lyase. AlyL1 might be an interesting candidate for biotechnological and industrial applications.

Part two: Library Research : Neurobehavioral toxicity in Wistar rats offspring after prenatal exposure to different doses of diazepam

( Li Shang ) 한국환경보건학회(구-한국환경위생학회) 2004 Current Challenges and Advances in Environmental H Vol.- No.-