Non-square colour image scrambling based on two-dimensional Sine-Logistic and Henon map

( Siqi Zhou ),( Feng Xu ),( Ping Ping ),( Zaipeng Xie ),( Xin Lyu ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.12

Image scrambling is an important technology in information hiding, where the Arnold transformation is widely used. Several researchers have proposed the application of Henon map in square image scrambling, and certain improved technologies require scrambling many times to achieve a good effect without resisting chosen-plaintext attack although it can be directly applied to non-square images. This paper presents a non-square image scrambling algorithm, which can resist chosen-plaintext attack based on a chaotic two-dimensional Sine Logistic modulation map and Henon map (2D-SLHM). Theoretical analysis and experimental results show that the proposed algorithm has advantages in terms of key space, efficiency, scrambling degree, ability of anti-attack and robustness to noise interference.

Determining Osteogenic Differentiation Efficacy of Pluripotent Stem Cells by Telomerase Activity

Siqi Zhang,Yuhua Sun,Yi Sui,Yan Li,Zuyuan Luo,Xiao Xu,Ping Zhou,Shicheng Wei 한국조직공학과 재생의학회 2018 조직공학과 재생의학 Vol.15 No.6

BACKGROUND: Bone tissue engineering based on pluripotent stem cells (PSCs) is a new approach to deal with bone defects. Protocols have been developed to generate osteoblasts from PSCs. However, the low efficiency of this process is still an important issue that needs to be resolved. Many studies have aimed to improve efficiency, but developing accurate methods to determine efficacy is also critical. Studies using pluripotency to estimate efficacy are rare. Telomerase is highly associated with pluripotency. METHODS: We have described a quantitative method to measure telomerase activity, telomeric repeat elongation assay based on quartz crystal microbalance (QCM). To investigate whether this method could be used to determine the efficiency of in vitro osteogenic differentiation based on pluripotency, we measured the pluripotency pattern of cultures through stemness gene expression, proliferation ability and telomerase activity, measured by QCM. RESULTS: We showed that the pluripotency pattern determined by QCM was similar to the patterns of proliferation ability and gene expression, which showed a slight upregulation at the late stages, within the context of the general downregulation tendency during differentiation. Additionally, a comprehensive gene expression pattern covering nearly every stage of differentiation was identified. CONCLUSION: Therefore, this assay may be powerful tools for determining the efficiency of differentiation systems based on pluripotency. In this study, we not only introduce a new method for determining efficiency based on pluripotency, but also provide more information about the characteristics of osteogenic differentiation which help facilitate future development of more efficient protocols.

Identification of drug target candidates of the swine pathogen Actinobacillus pleuropneumoniae by construction of protein–protein interaction network

Siqi Li,Zhipeng Su,Chengjun Zhang,Zhuofei Xu,Xiaoping Chang,Jiawen Zhu,Ran Xiao,Lu Li,Rui Zhou 한국유전학회 2018 Genes & Genomics Vol.40 No.8

Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae has led to severe economic losses in the pig industry worldwide. A. pleuropneumoniae displays various levels of antimicrobial resistance, leading to the dire need to identify new drug targets. Protein–protein interaction (PPI) network can aid the identification of drug targets by discovering essential proteins during the life of bacteria. The aim of this study is to identify drug target candidates of A. pleuropneumoniae from essential proteins in PPI network. The homologous protein mapping method (HPM) was utilized to construct A. pleuropneumoniae PPI network. Afterwards, the subnetwork centered with H-NS was selected to verify the PPI network using bacterial two-hybrid assays. Drug target candidates were identified from the hub proteins by analyzing the topology of the network using interaction degree and homologous comparison with the pig proteome. An A. pleuropneumoniae PPI network containing 2737 non-redundant interaction pairs among 533 proteins was constructed. These proteins were distributed in 21 COG functional categories and 28 KEGG metabolic pathways. The A. pleuropneumoniae PPI network was scale free and the similar topological tendencies were found when compared with other bacteria PPI network. Furthermore, 56.3% of the H-NS subnetwork interactions were validated. 57 highly connected proteins (hub proteins) were identified from the A. pleuropneumoniae PPI network. Finally, 9 potential drug targets were identified from the hub proteins, with no homologs in swine. This study provides drug target candidates, which are promising for further investigations to explore lead compounds against A. pleuropneumoniae.

Deformation Prediction and Deformation Characteristics of Multilayers of Mucky Clay under Artificial Freezing Condition

Yiqun Tang,Siqi Xiao,Jie Zhou 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.3

Artificial ground freezing method, is a popular technique applied in coastal soft soil area for underground engineering construction. This method can bring some side effects, like frost heave and thaw settlement, due to the water migration in soil during freezing-thawing process. A self-designed one-dimensional freezing apparatus is used to study the deformation performance of the reconstituted soft clay from Shanghai 4th layer during freezing-thawing process. Test results show that total frost heave amount increases with decreasing boundary freezing temperature while it remains with the variation of initial water content in the test. The deformation of multilayers during freezing process reveals compression phenomenon due to the water migration in the soil samples. The compression area is the main part contributed to thaw settlement. Besides, a prediction model is established with void ratio as a variable to connectfrost-heave model with thaw-settlement model. FDM (Finite Difference Method) method is used for computation through compiling code in MATLAB software. Comparison shows that compression phenomenon is necessary to be considered when calculating thaw settlement. This study provides valuable reference to the deformation control of soil in the construction of artificial ground freezing.

Voltage balance strategy for DC‑port failures of three‑phase cascaded H‑bridge rectifiers based on negative sequence current injection

Xiaohan Liu,Xiao Liang,Kaiyue Gong,Siqi An,Xu Peng,Jun Cai,Xinyu Zhu,Chao Zhou 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.8

The three-phase cascaded H-bridge rectifier (CHBR) is widely used in high power and high voltage applications. This paper focuses on the load removed from the DC port of a three-phase CHBR, which can cause single-phase DC-port voltage unbalance issues and three-phases DC-port voltage unbalance issues. This paper proposes a voltage balance control strategy based on negative sequence current injection for three-phase CHBR to deal with the unbalance problem. An individual DC-port voltage control strategy is designed to balance the DC-port voltage in the faulty phase. In addition, a negative sequence current injection control strategy is responsible for balancing the DC-port voltages in the three phase CHBR. The effectiveness and feasibility of the proposed voltage control strategy based on negative sequence current injection is verified by the experimental results.

miR-101 Inhibiting Cell Proliferation, Migration and Invasion in Hepatocellular Carcinoma through Downregulating Girdin

Cao, Ke,Li, Jingjing,Zhao, Yong,Wang, Qi,Zeng, Qinghai,He, Siqi,Yu, Li,Zhou, Jianda,Cao, Peiguo Korean Society for Molecular and Cellular Biology 2016 Molecules and cells Vol.39 No.2

miR-101 is considered to play an important role in hepatocellular carcinoma (HCC), but the underlying molecular mechanism remains to be elucidated. Here, we aimed to confirm whether Girdin is a target gene of miR-101 and determine the tumor suppressor of miR-101 through Girdin pathway. In our previous studies, we firstly found Girdin protein was overexpressed in HCC tissues, and it closely correlated to tumor size, T stage, TNM stage and Edmondson-Steiner stage of HCC patients. After specific small interfering RNA of Girdin was transfected into HepG2 and Huh7.5.1 cells, the proliferation and invasion ability of tumor cells were significantly inhibited. In this study, we further explored the detailed molecular mechanism of Girdin in HCC. Interestingly, we found that miR-101 significantly low-expressed in HCC tissues compared with that in matched normal tissues while Girdin had a relative higher expression, and miR-101 was inversely correlated with Girdin expression. In addition, after miR-101 transfection, the proliferation, migration and invasion abilities of HepG2 cells were weakened. Furthermore, we confirmed that Girdin is a direct target gene of miR-101. Finally we confirmed Talen-mediated Girdin knockout markedly suppressed cell proliferation, migration and invasion in HCC while downregulation of miR-101 significantly restored the inhibitory effect. Our findings suggested that miR-101/Girdin axis could be a potential application of HCC treatment.

miR-101 Inhibiting Cell Proliferation, Migration and Invasion in Hepatocellular Carcinoma through Downregulating Girdin

Peiguo Cao,Ke Cao,Jingjing Li,Yong Zhao,Qi Wang,Qinghai Zeng,Siqi He,Li Yu,Jianda Zhou 한국분자세포생물학회 2016 Molecules and cells Vol.39 No.2

miR-101 is considered to play an important role in hepatocellular carcinoma (HCC), but the underlying molecular mechanism remains to be elucidated. Here, we aimed to confirm whether Girdin is a target gene of miR-101 and determine the tumor suppressor of miR-101 through Girdin pathway. In our previous studies, we firstly found Girdin protein was overexpressed in HCC tissues, and it closely correlated to tumor size, T stage, TNM stage and Edmondson-Steiner stage of HCC patients. After specific small interfering RNA of Girdin was transfected into HepG2 and Huh7.5.1 cells, the proliferation and invasion ability of tumor cells were significantly inhibited. In this study, we further explored the detailed molecular mechanism of Girdin in HCC. Interestingly, we found that miR-101 significantly low-expressed in HCC tissues compared with that in matched normal tissues while Girdin had a relative higher expression, and miR-101 was inversely correlated with Girdin expression. In addition, after miR-101 transfection, the proliferation, migration and invasion abilities of HepG2 cells were weakened. Furthermore, we confirmed that Girdin is a direct target gene of miR-101. Finally we confirmed Talen-mediated Girdin knockout markedly suppressed cell proliferation, migration and invasion in HCC while down-regulation of miR-101 significantly restored the inhibitory effect. Our findings suggested that miR-101/Girdin axis could be a potential application of HCC treatment.

Negative sequence control for DC voltage balancing in three‑phase cascaded H‑bridge rectifiers considering DC‑port failures

Xinyu Zhu,Xiao Liang,Kaiyue Gong,Xu Peng,Jun Cai,Xiaohan Liu,Chao Zhou,Siqi An,Chao Wu,Pengcheng Han 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.12

As a vital component of power electronic transformers (PET), the reliability of a cascaded H-bridge rectifier (CHBR) is essential. Therefore, in this paper, a DC-port voltage balance strategy considering DC-port failure is researched to ensure the stable operation of a CHBR. However, if the DC-port voltage balance strategy is adopted to realize the single-phase balance of a CHBR, the three-phase currents become unbalanced. This paper uses a negative sequence control (NSC) strategy that is conducive to balancing DC-port voltage to achieve three-phase current balance. For the DC-port voltage balance, the matrix generation modulation (MGM) algorithm is proposed. In addition, the DC-port voltage balance boundary is analyzed to determine the range of the DC-port voltage balance in the CHBR. A 3-module cascading topology is adopted to demonstrate the MGM algorithm and the NSC strategy. Through experiments, results show the correctness and feasibility of the proposed strategy.