3D Porous Graphene/Polyvinyl Alcohol Composites: The Effect of Modification on the Adsorption Properties

Shuang Sun,Xiaofei Ma 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.11

Polyvinyl alcohol (PVA) was grafted on graphene nanosheets (GN) in the reduction of graphene oxide with hydrazine hydrate. The obtained GN-PVA (GP) suspension was treated with the freezing– thawing cycle to fabricate 3D porous monolithic GP materials, which were modified with carbon disulfide to introduce xanthan groups on the wall of porous materials, marked as GPCs. The characterization of GPCs confirmed that PVA was attached on the surface of GNs, and xanthan groups were effectively functionalized on the porous structures, which were composed of randomly oriented GNs. The Pb2+ adsorption pattern for GPC materials was investigated. The kinetic adsorption and isotherm data fit the pseudo second-order kinetic and the Langmuir isotherm models, respectively. The maximum adsorption capacity of Pb2+ reached 242.7 mg/g. And GPCs for Pb2+ adsorption could be regenerated with ethylenediamine tetracetic acid (EDTA) solution for repetitious adsorption.

Liraglutide Immobilized on Poly(lactic-co-glycolic acid) Polymer Films Induced the Differentiation of Islet β-Like Cells from Bone Marrow Mesenchymal Stem Cells

Shuang Sun,Weiwei Cui,Ying Dong,Qing Wang 한국고분자학회 2019 Macromolecular Research Vol.27 No.5

An organoid is a kind of three-dimensional cell culture system that is highly similar to the source tissues or organs in the body. Recently, organoid therapy has become a hot topic in the field of fundamental researches and clinical treatments. Type 1 diabetes mellitus (T1DM) is caused by the absolute lack of insulin. Exogenous insulin supplement, the only treatment currently available for T1DM, has nonideal effect due to the poor compliance. An implantable and sustainable strategy of T1DM is needed and the organoids theoretically provide the basis for treatment. However, the current structure and function of organoids are different from that of real organs or tissues. The organic scaffolds can effectively support the growth of organoids, which can increase the similarity of organoids to the real structure. In order to find suitable scaffold materials for islet β-like cells (IBCs) organoids, poly (lactic-co-glycolic acid) (PLGA) polymer films were prepared to act as induced carriers for IBCs derived from bone marrow mesenchymal stem cells (BMSCs). The surface of PLGA film was simply modified through dopamine (DA) coating (i.e., DA-PLGA) and then liraglutide (LIR) was fixed on the surface of PLGA film via the DA coating (i.e., LIR-DA-PLGA). The results proved that DA could enhance the hydrophilicity and cell proliferation and LIR-DA-PLGA was suitable to act as inducing carriers. In subsequent experiments, LIR-DA-PLGA scaffolds would be prepared to culture organoids and transplanted into the body of diabetic rat model to regulate blood glucose lever.

Association between the Epidermal Growth Factor 61^*A/G Polymorphism and Hepatocellular Carcinoma Risk: a Meta-Analysis

Sun, Shuang,Jin, Guo-Jiang,Zhao, Yan,Kang, Hui Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.7

The epidermal growth factor (EGF) may play a pathological role in hepatocellular carcinoma (HCC). However, the conclusions of published reports on the relationship between the EGF $61^*A/G$ polymorphism and HCC risk remain controversial. To derive a more precise estimation we performed a meta-analysis based on 14 studies that together included 2,506 cases and 4,386 controls. PubMed, EMBASE, Web of Knowledge and the Chinese National Knowledge Infrastructure (CNKI) databases were used to retrieve articles up to August 1, 2014. The crude odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated to evaluate the association. Meta-analysis results showed a significant association between the EGF $61^*A/G$ polymorphism and HCC risk in all four genetic models (allele model: OR=1.25, 95%CI=1.12-1.40; dominant model: OR=1.32, 95%CI=1.14-1.54; recessive model: OR=1.33, 95%CI=1.12-1.58; ho-mozygous model: OR=1.59, 95%CI=1.33-1.90). Moreover, significant associations were observed when stratified by ethnicity, source of controls, etiology and genotype methods. Thus, this meta-analysis suggests that the G-allele of the EGF $61^*A/G$ polymorphism is associated with an increased risk of HCC, especially in Asians and Caucasians, without influence from the source of controls or etiological diversity. Further studies with larger population sizes are needed to confirm these results.

Condition Assessment of Stay Cables via Cloud Evidence Fusion

Shuang Sun,Li Liang,Ming Li 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.3

Since the monitoring of cable tension are rather susceptible to environmental influence and external loads, the condition assessment of stay cables is vitally difficult because of these uncertainties. In this paper, regarding the health condition of stay cables, a multilevel assessment framework is presented, which can synthetically combined the evaluation results from numerical simulation, field monitoring and visual inspection. Based on these methods, three qualitative and three quantitative indices are selected as the evaluation indices. To reduce the uncertainties during the assessment procedure, an intelligent methodology based on cloud model and Dempster-Shafer (D-S) evidence theory is proposed. With the combination of forward cloud generator and backward cloud generator, the cloud parameters of in-situ data is transmitted to the cloud model of grade criteria, then the cloud evidence with relative weights are fused by Dempster combination, the condition grade of the cable is finally obtained. The Junshan Yangtze River Bridge is adopted to verify the effectiveness of the proposed methodology. The results show that the uncertainty degree can be obviously reduced from 55.7% to 6.7%, so that a scientific evaluation of cable conditions can be obtained. The multilevel assessment framework proposed in this study can serve as an effective basis for cable replacement and maintenance.

Vibration-based Damage Detection in Bridges via Machine Learning

Shuang Sun,Li Liang,Ming Li,Xinli Wang 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.12

Environmental corrosion and external loads degrade the performance of a bridge over the course of its service life. Although dynamic fingerprints are damage-sensitive, they are rarely applied to bridges in-situ due to environmental noise. Machine learning techniques can facilitate effective structural damage detection. This paper proposes a detection method based on dynamic fingerprints and machine learning techniques for multi-damage problems in bridges. Vibration analysis is conducted to acquire the dynamic fingerprints, then the Bayesian fusion is used to integrate these features and preliminarily locate the damage. The RSNB method, which combines Rough Set theory and the Naive-Bayes classifier, is introduced as a robust classification tool for damage qualification. A continuous bridge is numerically simulated to validate the effectiveness of the proposed method. The RSNB method is compared with back propagation neural network, support vector machine, and decision tree techniques, it is found that the RSNB outperforms other three methods in terms of transparency, accuracy, efficiency, noise robustness, and stability.

Cys-92, Cys-95, and the C-Terminal 12 Residues of the Vibrio harveyi Ferric Uptake Regulator (Fur) are Functionally Inessential

Kun Sun,Shuang Cheng,Min Zhang,Fang Wang,Li Sun 한국미생물학회 2008 The journal of microbiology Vol.46 No.6

Ferric uptake regulator (Fur) is a global regulator involved in multiple aspects of bacterial life. The gene encoding the Vibrio harveyi Fur (FurVh) was cloned from a pathogenic V. harveyi strain isolated from diseased fish. FurVh shares 77% overall sequence identity with the Escherichia coli Fur (FurEc) and could complement a mutant of FurEc. Like FurEc, FurVh possesses two cysteine residues at positions 92 and 95, yet unlike FurEc, in which these cysteine residues constitute part of the metal ion coordination site and hence are vital to the repressor activity, C92 and C95 of FurVh proved to be functionally inessential. Further study identified a Vibrio Fur signature sequence, which is preserved in all the ten Vibrio Fur proteins that have been discovered to date but in none of the non-vibrio Fur proteins. Site-directed and random mutation analyses of the signature residues, the cysteine residues, and seven highly charged amino acid residues indicated that D9, H32, C137, and K138 of FurVh are functionally important but D9, C137, and K138 can be replaced by more than one functional substitutes. Systematic deletion analysis demonstrated that the C-terminal 12 residues of FurVh are functionally inessential. These results (i) indicated that the activation mechanism, or certain aspects of which, of FurVh is possibly different from that of FurEc; and (ii) suggested that it is not very likely that the C-terminal 12 residues play any significant role in the activation or stability of FurVh; and (iii) provided insights into the potential function of the local structure involving C137 and K138.

MAPK4 silencing in gastric cancer drives liver metastasis by positive feedback between cancer cells and macrophages

Li Shuang,Guo Dongyang,Sun Qiang,Zhang Lu,Cui Yun,Liu Min,Ma Xixi,Liu Yiman,Cui Wenyu,Sun Leimin,Teng Lisong,Wang Liangjing,Lin Aifu,Liu Wei,Zhuo Wei,Zhou Tianhua 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Liver metastasis is a major cause of death in gastric cancer patients, but the underlying mechanisms are poorly understood. Through a combination of in vivo screening and transcriptome profiling followed by quantitative RT-PCR and tissue array analyses, we found that mitogen-activated protein kinase 4 (MAPK4) downregulation in gastric cancer tissues from patients is significantly associated with liver metastasis and poor prognosis. The knockdown of MAPK4 in gastric cancer cells promotes liver metastasis in orthotopic mouse models. MAPK4 depletion in gastric cancer cells induces the secretion of macrophage migration inhibitory factor (MIF) to polarize tumor-associated macrophages (TAMs) in orthotopic xenograft tumors. Moreover, TAMs activate epithelial–mesenchymal transition of gastric cancer cells to suppress MAPK4 expression, which further increases MIF secretion to polarize TAMs. Taken together, our results suggest a previously undescribed positive feedback loop between cancer cells and macrophages mediated by MAPK4 silencing that facilitates gastric cancer liver metastasis.

Halomonas alkalitolerans sp. nov., a Novel Moderately Halophilic Bacterium Isolated from Soda Meadow Saline Soil in Daqing, China

Shuang Wang,Qian Yang,Zhi-Hua Liu,Lei Sun,Dan Wei,Jun-Zheng Zhang,Jin-Zhu Song,Yun Wang,Jia Song,Jin-Xia Fan,Xian-Xin Meng,Wei Zhang 한국미생물학회 2011 The journal of microbiology Vol.49 No.1

A moderately halophilic bacterial strain 15-13^T, which was isolated from soda meadow saline soil in Daqing City, Heilongjiang Province, China, was subjected to a polyphasic taxonomic study. The cells of strain 15-13^T were found to be Gram-negative, rod-shaped, and motile. The required growth conditions for strain 15-13^T were: 1-23% NaCl (optimum, 7%), 10-50°C (optimum, 35°C), and pH 7.0-11.0 (optimum, pH 9.5). The predominant cellular fatty acids were C18:1 ω7c (60.48%) and C16:0 (13.96%). The DNA G+C content was 67.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons indicated that strain 15-13^T clustered within a branch comprising species of the genus Halomonas. The closest phylogenetic neighbor of strain 15-13^T was Halomonas pantelleriensis DSM 9661^T (98.9% 16S rRNA gene sequence similarity). The level of DNA-DNA relatedness between the novel isolated strain and H. pantelleriensis DSM 9661^T was 33.8%. On the basis of the phenotypic and phylogenetic data, strain 15-13^T represents a novel species of the genus Halomonas, for which the name Halomonas alkalitolerans sp. nov. is proposed. The type strain for this novel species is 15-13^T (=CGMCC 1.9129^T =NBRC 106539^T).

Design and Practice of Teacher Training Supported by a Web 2.0 Community

Shuang Li,Li Chen,Hongtao Sun APEC국제교육협력원 2010 Asia-Pacific Cybereducation Journal Vol.6 No.2

Web 2.0 communities are providing new opportunities for teachers’ professional development by supporting more flexible sharing, communicating, and collaborating among teachers at a distance. Meanwhile, literature concerning teachers’ professional development increasingly places value on communities of practice and web-based learning communities. This paper presents a case study on the design of teacher training supported by a Web 2.0 community. The training program discussed in the paper is characterized by employing peer-coaching to facilitate teachers’ learning in a Web 2.0 community, and is a part of a project funded by the Ford Foundation. The paper gives a brief introduction to the training program, and reports some important findings and reflections on design and practice for in-service teacher training. It includes the theoretical framework design, a training model as well as activity design, and the implementation and evaluation of the training program and useful experiences. Initially, taking account school teachers’ needs at the K12 level for curriculum reform and quality education, theory, knowledge and practice competences for learner-centered instruction were examined by using peer-coaching methods supported by online communities. The suggested training program was delivered in two Chinese districts in August 2009: Tianhe district of Guangzhou, and Wuhou district of Chengdu. More than 120 participants, including subject teachers, school principals and local teaching researchers, took part in the f2f training, online activities and the further practice activities. Even still on-going, the comprehensive investigation and evaluation of the training program explains that the initial results and observations collected during the process of training are very positive. With cause for optimism as to the prospect of achieving the training program’s goals, the study has demonstrated that a task-driven approach and peer-coaching supported by a web 2.0 community are effective methods for in-service teacher training, and that peer-coaching can be greatly extended by out-of-school activities.

Manufacturing Enterprise, Tourism Industry and Economic Development Coupling Coordinative in Jilin Province, China

Shuang-Yu Hu(호쌍우),Yu-Cong Sun(손우총),Zhi-Run Li(이지윤),Jong-In Lee(이종인) 한국산학기술학회 2022 한국산학기술학회논문지 Vol.23 No.1