EXPERIMENTAL NANOMECHANICS OF ONE-DIMENSIONAL NANOMATERIALS BY IN SITU MICROSCOPY

XIAODONG HAN,ZE ZHANG,ZHONG LIN WANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2007 NANO Vol.2 No.5

This paper provides a comprehensive review on the methodological development and technical applications of in situ microscopy, including transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM), developed in the last decade for investigating the structure-mechanical-property relationship of a single one-dimensional nanomaterial, such as nanotube, nanowire and nanobelt. The paper covers both the fundamental methods and detailed applications, including AFM-based static elastic and plastic measurements of a carbon nanotube, external field-induced resonance dynamic measurement of elastic modulus of a nanotube/nanowire, nano-indentation, and in situ plastic deformation process of a nanowire. Details are presented on the elastic property measurements and direct imaging of plastic to superplastic behavior of semiconductor nanowires at atomic resolution, providing quantitative information on the mechanical behavior of nanomaterials. The studies on the Si and SiC nanowires clearly demonstrated their distinct, "unexpected" and superior plastic mechanical properties. Finally, a perspective is given on the future of nanomechanics.

Methylation-associated silencing of BASP1 contributes to leukemogenesis in t(8;21) acute myeloid leukemia

Lei Zhou,Lin Fu,Na Lv,Jing Liu,Yan Li,Xiaosu Chen,Qingyu Xu,Guofeng Chen,Baoxu Pang,Lili Wang,Yonghui Li,Xiaodong Zhang,Li Yu 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

The AML1-ETO fusion protein (A/E), which results from the t(8;21) translocation, is considered to be a leukemiainitiating event. Identifying the mechanisms underlying the oncogenic activity of A/E remains a major challenge. In this study, we identified a specific down-regulation of brain acid-soluble protein 1 (BASP1) in t(8;21) acute myeloid leukemia (AML). A/E recognized AML1-binding sites and recruited DNA methyltransferase 3a (DNMT3a) to the BASP1 promoter sequence, which triggered DNA methylation-mediated silencing of BASP1. Ectopic expression of BASP1 inhibited proliferation and the colony-forming ability of A/E-positive AML cell lines and led to apoptosis and cell cycle arrest. The DNMT inhibitor decitabine up-regulated the expression of BASP1 in A/E-positive AML cell lines. In conclusion, our data suggest that BASP1 silencing via promoter methylation may be involved in A/E-mediated leukemogenesis and that BASP1 targeting may be an actionable therapeutic strategy in t(8;21) AML.

Radio Resource Management of CoMP System in HetNet under Power and Backhaul Constraints

( Jia Yu ),( Shaohua Wu ),( Xiaodong Lin ),( Qinyu Zhang ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.11

Recently, Heterogeneous Network (HetNet) with Coordinated Multi-Point (CoMP) scheme is introduced into Long Term Evolution-Advanced (LTE-A) systems to improve digital services for User Equipments (UEs), especially for cell-edge UEs. However, Radio Resource Management (RRM), including Resource Block (RB) scheduling and Power Allocation (PA), in this scenario becomes challenging, due to the intercell cooperation. In this paper, we investigate the RRM problem for downlink transmission of HetNet system with Joint Processing (JP) CoMP (both joint transmission and dynamic cell selection schemes), aiming at maximizing weighted sum data rate under the constraints of both transmission power and backhaul capacity. First, joint RB scheduling and PA problem is formulated as a constrained Mixed Integer Programming (MIP) which is NP-hard. To simplify the formulation problem, we decompose it into two problems of RB scheduling and PA. For RB scheduling, we propose an algorithm with less computational complexity to achieve a suboptimal solution. Then, according to the obtained scheduling results, we present an iterative Karush-Kuhn- Tucker (KKT) method to solve the PA problem. Extensive simulations are conducted to verify the effectiveness and efficiency of the proposed algorithms. Two kinds of JP CoMP schemes are compared with a non-CoMP greedy scheme (max capacity scheme). Simulation results prove that the CoMP schemes with the proposed RRM algorithms dramatically enhance data rate of cell-edge UEs, thereby improving UEs` fairness of data rate. Also, it is shown that the proposed PA algorithms can decrease power consumption of transmission antennas without loss of transmission performance.

NUND: Non-Uniform Node Distribution in Cluster-based Wireless Sensor Networks

( Ju Ren ),( Yaoxue Zhang ),( Xiaodong Lin ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.7

Cluster-based wireless sensor network (WSN) can significantly reduce the energy consumption by data aggregation and has been widely used in WSN applications. However, due to the intrinsic many-to-one traffic pattern in WSN, the network lifetime is generally deteriorated by the unbalanced energy consumption in a cluster-based WSN. Therefore, energy efficiency and network lifetime improvement are two crucial and challenging issues in cluster-based WSNs. In this paper, we propose a Non-Uniform Node Distribution (NUND) scheme to improve the energy efficiency and network lifetime in cluster-based WSNs. Specifically, we first propose an analytic model to analyze the energy consumption and the network lifetime of the cluster-based WSNs. Based on the analysis results, we propose a node distribution algorithm to maximize the network lifetime with a fixed number of sensor nodes in cluster-based WSNs. Extensive simulations demonstrate that the theoretical analysis results determined by the proposed analytic model are consistent with the simulation results, and the NUND can significantly improve the energy efficiency and network lifetime.

Intention-Oriented Itinerary Recommendation Through Bridging Physical Trajectories and Online Social Networks

( Xiangxu Meng ),( Xinye Lin ),( Xiaodong Wang ),( Xingming Zhou ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.12

Compared with traditional itinerary planning, intention-oriented itinerary recommendations can provide more flexible activity planning without requiring the user`s predetermined destinations and is especially helpful for those in unfamiliar environments. The rank and classification of points of interest (POI) from location-based social networks (LBSN) are used to indicate different user intentions. The mining of vehicles` physical trajectories can provide exact civil traffic information for path planning. This paper proposes a POI category-based itinerary recommendation framework combining physical trajectories with LBSN. Specifically, a Voronoi graph-based GPS trajectory analysis method is utilized to build traffic information networks, and an ant colony algorithm for multi-object optimization is implemented to locate the most appropriate itineraries. We conduct experiments on datasets from the Foursquare and GeoLife projects. A test of users` satisfaction with the recommended items is also performed. Our results show that the satisfaction level reaches an average of 80%.

PEC: A Privacy-Preserving Emergency Call Scheme for Mobile Healthcare Social Networks

Xiaohui Liang,Rongxing Lu,Le Chen,Xiaodong Lin,Xuemin (Sherman) Shen 한국통신학회 2011 Journal of communications and networks Vol.13 No.2

In this paper, we propose a privacy-preserving emergency call scheme, called PEC, enabling patients in life-threatening emergencies to fast and accurately transmit emergency data to the nearby helpers via mobile healthcare social networks (MHSNs). Once an emergency happens, the personal digital assistant (PDA)of the patient runs the PEC to collect the emergency data including emergency location, patient health record, as well as patient physiological condition. The PEC then generates an emergency call with the emergency data inside and epidemically disseminates it to every user in the patient’s neighborhood. If a physician happens to be nearby, the PEC ensures the time used to notify the physician of the emergency is the shortest. We show via theoretical analysis that the PEC is able to provide fine-grained access control on the emergency data, where the access policy is set by patients themselves. Moreover,the PEC can withstandmultiple types of attacks, such as identity theft attack, forgery attack, and collusion attack. We also devise an effective revocation mechanism to make the revocable PEC (rPEC) resistant to inside attacks. In addition, we demonstrate via simulation that the PEC can significantly reduce the response time of emergency care in MHSNs.

PEC: A Privacy-Preserving Emergency Call Scheme for Mobile Healthcare Social Networks

Liang, Xiaohui,Lu, Rongxing,Chen, Le,Lin, Xiaodong,Shen, Xuemin (Sherman) The Korea Institute of Information and Commucation 2011 Journal of communications and networks Vol.13 No.2

In this paper, we propose a privacy-preserving emergency call scheme, called PEC, enabling patients in life-threatening emergencies to fast and accurately transmit emergency data to the nearby helpers via mobile healthcare social networks (MHSNs). Once an emergency happens, the personal digital assistant (PDA) of the patient runs the PEC to collect the emergency data including emergency location, patient health record, as well as patient physiological condition. The PEC then generates an emergency call with the emergency data inside and epidemically disseminates it to every user in the patient's neighborhood. If a physician happens to be nearby, the PEC ensures the time used to notify the physician of the emergency is the shortest. We show via theoretical analysis that the PEC is able to provide fine-grained access control on the emergency data, where the access policy is set by patients themselves. Moreover, the PEC can withstandmultiple types of attacks, such as identity theft attack, forgery attack, and collusion attack. We also devise an effective revocation mechanism to make the revocable PEC (rPEC) resistant to inside attacks. In addition, we demonstrate via simulation that the PEC can significantly reduce the response time of emergency care in MHSNs.

Robust Key Agreement From Received Signal Strength in Stationary Wireless Networks

( Aiqing Zhang ),( Xinrong Ye ),( Jianxin Chen ),( Liang Zhou ),( Xiaodong Lin ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.5

Key agreement is paramount in secure wireless communications. A promising approach to address key agreement schemes is to extract secure keys from channel characteristics. However, because channels lack randomness, it is difficult for wireless networks with stationary communicating terminals to generate robust keys. In this paper, we propose a Robust Secure Key Agreement (RSKA) scheme from Received Signal Strength (RSS) in stationary wireless networks. In order to mitigate the asymmetry in RSS measurements for communicating parties, the sender and receiver normalize RSS measurements and quantize them into q-bit sequences. They then reshape bit sequences into new l-bit sequences. These bit sequences work as key sources. Rather than extracting the key from the key sources directly, the sender randomly generates a bit sequence as a key and hides it in a promise. This is created from a polynomial constructed on the sender`s key source and key. The receiver recovers the key by reconstructing a polynomial from its key source and the promise. Our analysis shows that the shared key generated by our proposed RSKA scheme has features of high randomness and a high bit rate compared to traditional RSS-based key agreement schemes.

Preclinical investigation of artesunate as a therapeutic agent for hepatocellular carcinoma via impairment of glucosylceramidase-mediated autophagic degradation

Chen Wenjia,Ma Zhaochen,Yu Lingxiang,MAO Xia,Ma Nan,Guo Xiaodong,Yin Xiaoli,Jiang Funeng,Wang Qian,Wang Jigang,Fang Mingliang,Lin Na,Zhang Yanqiong 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Artesunate (ART) has been indicated as a candidate drug for hepatocellular carcinoma (HCC). Glucosylceramidase (GBA) is required for autophagic degradation. Whether ART regulates autophagic flux by targeting GBA in HCC remains to be defined. Herein, our data demonstrated that the dramatic overexpression of GBA was significantly associated with aggressive progression and short overall survival times in HCC. Subsequent experiments revealed an association between autophagic activity and GBA expression in clinical HCC samples, tumor tissues from a rat model of inflammation-induced HCC and an orthotopic mouse model, and human HCC cell lines. Interestingly, probe labeling identified GBA as an ART target, which was further verified by both a glutathione-S-transferase pulldown assay and surface plasmon resonance analysis. The elevated protein expression of LC3B, the increased numbers of GFP-LC3B puncta and double-membrane vacuoles, and the enhanced expression of SQSTM1/p62 indicated that the degradation of autophagosomes in HCC cells was inhibited by ART treatment. Both the in vitro and in vivo data revealed that autophagosome accumulation through targeting of GBA was responsible for the anti-HCC effects of ART. In summary, this preclinical study identified GBA as one of the direct targets of ART, which may have promising potential to inhibit lysosomal autophagy for HCC therapy.

Enabling Fine-grained Access Control with Efficient Attribute Revocation and Policy Updating in Smart Grid

( Hongwei Li ),( Dongxiao Liu ),( Khalid Alharbi ),( Shenmin Zhang ),( Xiaodong Lin ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.4

In smart grid, electricity consumption data may be handed over to a third party for various purposes. While government regulations and industry compliance prevent utility companies from improper or illegal sharing of their customers` electricity consumption data, there are some scenarios where it can be very useful. For example, it allows the consumers` data to be shared among various energy resources so the energy resources are able to analyze the data and adjust their operation to the actual power demand. However, it is crucial to protect sensitive electricity consumption data during the sharing process. In this paper, we propose a fine-grained access control scheme (FAC) with efficient attribute revocation and policy updating in smart grid. Specifically, by introducing the concept of Third-party Auditor (TPA), the proposed FAC achieves efficient attribute revocation. Also, we design an efficient policy updating algorithm by outsourcing the computational task to a cloud server. Moreover, we give security analysis and conduct experiments to demonstrate that the FAC is both secure and efficient compared with existing ABE-based approaches.