917 results on '"Ximeng LIU"'
Search Results
902. A key-insulated CP-ABE with key exposure accountability for secure data sharing in the cloud.
- Author
-
Hanshu Hong, Zhixin Sun, and Ximeng Liu
- Subjects
DATA security ,INFORMATION sharing ,CLOUD computing ,DATA protection ,INTERNET users ,DATA encryption - Abstract
ABE has become an effective tool for data protection in cloud computing. However, since users possessing the same attributes share the same private keys, there exist some malicious users exposing their private keys deliberately for illegal data sharing without being detected, which will threaten the security of the cloud system. Such issues remain in many current ABE schemes since the private keys are rarely associated with any user specific identifiers. In order to achieve user accountability as well as provide key exposure protection, in this paper, we propose a key-insulated ciphertext policy attribute based encryption with key exposure accountability (KI-CPABE-KEA). In our scheme, data receiver can decrypt the ciphertext if the attributes he owns match with the self-centric policy which is set by the data owner. Besides, a unique identifier is embedded into each user's private key. If a malicious user exposes his private key for illegal data sharing, his identity can be exactly pinpointed by system manager. The key-insulation mechanism guarantees forward and backward security when key exposure happens as well as provides efficient key updating for users in the cloud system. The higher efficiency with proved security make our KI-CPABE-KEA more appropriate for secure data sharing in cloud computing. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
903. Provably secure unbounded multi-authority ciphertext-policy attribute-based encryption.
- Author
-
Qi Li, Jianfeng Ma, Rui Li, Jinbo Xiong, and Ximeng Liu
- Subjects
CIPHERS ,DATA encryption ,PHASE shift keying ,ACCESS control ,PSEUDONOISE sequences (Digital communications) ,POLYNOMIAL time algorithms - Abstract
Multi-authority attribute-based encryption (ABE) is a generation of ABE where the descriptive attributes are managed by different authorities. In current multi-authority ABE schemes, the scale of attribute universe employed in encryption is restricted by various predefined thresholds. In this paper, we propose an unbounded multi-authority ciphertext-policy ABE system without such restriction. Our scheme consists of multiple attribute authorities (AAs), one central authority (CA), and users labeled by the set of attributes. Each AA governs a different universe of attributes and operates separately. Moreover, there is no cooperation between the CA and AAs. To provide the private keys for a user, the AAs first issue partial attribute-related keys according to the attributes; the CA then issues identity-related keys and links these attribute-keys with the user's global identifier. Both the identity-related and the linked attribute-related keys will be used in decryption. The proposed multi-authority ciphertext-policy ABE scheme can support arbitrary linear secret sharing scheme as the access policy. Performance analysis and security proof indicate that our scheme is efficient and secure. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
904. Access control requirements for structured document in cloud computing
- Author
-
Qi Li, Zhiqiang Yao, Jianfeng Ma, Ximeng Liu, and Jinbo Xiong
- Subjects
Cloud computing security ,Computer science ,business.industry ,Applied Mathematics ,Cloud computing ,Access control ,Computer Science Applications ,Management Information Systems ,World Wide Web ,Structured document ,Work (electrical) ,Key (cryptography) ,Multilevel security ,business ,Vision document - Abstract
Structured document plays a vital role in the information carrier in cloud computing. So apparently, secure access to structured document is a key technology for the quality control of cloud services. However, there is no prior work on discussing access control requirements for structured document in cloud computing. In this paper, we describe the 'live' characteristics of structured document and tenants' diverse action patterns to access structured document in cloud computing. And then, we systematically present the access control requirements for structured document in cloud computing from the following aspects: action-based, control tenants' access actions, tenants' privacy protection, fine-grained, multilevel security, and self-adaptive policies. Finally, we present an Action-Based Multilevel Access Control ABMAC model framework to implement the access control requirements. This work will provide a powerful support for proposing an efficient structured document protection framework in cloud computing.
- Published
- 2013
905. SPEMR: A new secure personal electronic medical record scheme with privilege separation.
- Author
-
Zhu, Hui, Rong Huang, Ximeng Liu, and Li, Hui
- Published
- 2014
- Full Text
- View/download PDF
906. Abstract 3727: Targeting autotaxin to reduce chemotherapy resistance in ovarian cancer
- Author
-
Yimin Wang, Rongbao Li, Ronald D. Alvarez, Zhican Qu, Ling Zhai, Jacob M. Estes, Ximeng Liu, Ali Zamani, and Yulia Maxuitenko
- Subjects
Cisplatin ,Cancer Research ,Chemotherapy ,business.industry ,medicine.medical_treatment ,Cancer ,Pharmacology ,medicine.disease ,chemistry.chemical_compound ,Ovarian tumor ,Oncology ,chemistry ,Paclitaxel ,Lysophosphatidic acid ,medicine ,Cancer research ,Autotaxin ,Ovarian cancer ,business ,medicine.drug - Abstract
Development of resistance to chemotherapy presents the biggest challenge in the treatment of ovarian cancer. Autotaxin (ATX) is a secreted enzyme that catalyzes lysophosphatidic acid (LPA) production and is responsible for the up-regulation of LPA in ovarian cancer. The ATX-LPA axis has been identified to be one of the mechanisms of chemotherapy resistance in ovarian cancer. Thus, inhibition of autotaxin may be a potential strategy to increase the chemotherapy efficacy in this disease context. At Southern Research, we previously identified a known anti-parasitic small molecule, Bithionol as a potent antiangiogenic agent, which inhibits endothelial cell proliferation, migration and tubular morphogenesis in vitro and directly inhibits autotaxin enzyme activity. Our recent results have shown that Bithionol not only directly inhibits the enzyme activity; it also reduces autotaxin secretion from human endothelial and ovarian cancer cells. Recently, using a human ovarian cancer xenograft mouse model, Biothionol was shown to have in vivo anti-tumor activity as a single drug treatment. In addition, in combination therapy studies in mice, Bithionol significantly increased the efficacy of Paclitaxel and Cisplatin against ovarian tumor growth. These results suggest that Bithionol may provide a promising approach for reducing chemotherapy associated resistance in ovarian cancer. Additional preclinical studies are in progress to assess the potential clinical utility of Bithionol in combination with current ovarian cancer therapy. (This work is supported by a pilot grant from Norma Livingston Foundation and SRI SIP fund). Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3727. doi:1538-7445.AM2012-3727
- Published
- 2012
907. Abstract 4265: Bithionol as an inhibitor of tumor angiogenesis
- Author
-
Ximeng Liu, Ling Zhai, Ali Zamani, Rongbao Li, Anshu Mittal Roy, Yimin Wang, and Zhican Qu
- Subjects
Cancer Research ,business.industry ,Angiogenesis ,Cancer ,Pharmacology ,medicine.disease ,Metastasis ,chemistry.chemical_compound ,Oncology ,chemistry ,Tumor progression ,Cancer cell ,Lysophosphatidic acid ,medicine ,Autotaxin ,business ,Ex vivo - Abstract
Tumor progression depends on angiogenesis. The clinical successes in recent years have demonstrated that antiangiogenic agents can be developed as effective treatment for cancer patients. However, the resistance to the current FDA approved antiangiogenic therapies is emerging, which presents challenges in cancer research and urgent needs for novel angiogenesis inhibitors with different mechanisms of drug actions to overcome the resistance. In our previous studies, we have identified a small molecule bithionol as a potential antiangiogenic agent through a chemical diversity library screening with a cell-based angiogenesis assay. Bithionol is a FDA approved and current clinically used anthelmintics, which has been found to directly inhibit activity of autotaxin, a secreted enzyme that catalyzes lysophosphatidic acid (LPA) production. LPA, as a lipid signaling molecule, is a potent angiogenic and cancer cell motility stimulating factor. Therefore, autotaxin plays important role in tumor angiogenesis and metastasis and has been recently identified as an attractive angiogenesis and cancer target. Our recent studies have shown that autotaxin is expressed at high levels in human endothelial and number of human cancer cell lines. Bithionol has demonstrated inhibitory activities against human endothelial cell proliferation, migration, and tube-formation as the three key cellular steps in angiogenesis process. The effect of bithionol on inhibition of tumor angiogenesis was also evaluated with an ex vivo xenograft chicken embryo chorioallantoic membrane (xenograft-CAM) model system. Bithionol is able to inhibit tumor-induced new blood vessel formation in a dose dependent manner and has demonstrated an additive inhibitory activity when it is applied in combination with Sutent, a current clinically used antiangiogenic drug. The results of this research suggest that bithionol provide a unique promising opportunity in developing new combinational treatment to increase the anticancer efficacy and minimize the resistance in cancer patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4265. doi:10.1158/1538-7445.AM2011-4265
- Published
- 2011
908. Efficacy of judicial independence in explaining financial markets in emerging markets
- Author
-
Ximeng, Liu and Zhiwen., Li
- Abstract
The relationship between institutional quality, financial development, and economic growth has been well documented in the literature. However, much less work has been done the effect of judicial independence (JI) on financial market development (FM) in particular. This paper fills that gap using the JI score and FM in the context of 23 emerging markets (as identified by the Financial Times Stock Exchange Group) over the period 1980-2021. Overall, the results suggest that, in selected emerging markets JI fosters FM. Interestingly, the results across various quantiles of JI show that low JI hampers FM, but a medium and high level of JI boosts FM in these markets. These results are robust to several specifications. To the best of our knowledge, this is the first study to examine the direct impact of JI on FM and confirms the theories on new institutional economics as well as law and finance in emerging markets.
- Published
- 2023
- Full Text
- View/download PDF
909. PRIAM: Privacy Preserving Identity and Access Management Scheme in Cloud.
- Author
-
Jinbo Xiong, Zhiqiang Yao, Jianfeng Ma, Ximeng Liu, Qi Li, and Jun Ma
- Subjects
CLOUD computing ,IDENTITY management systems ,INFORMATION technology security ,CRYPTOGRAPHY ,ACCESS control - Abstract
Each cloud service has numerous owners and tenants, so it is necessary to construct a privacy preserving identity management and access control mechanism for cloud computing. On one hand, cloud service providers (CSP) depend on tenant's identity information to enforce appropriate access control so that cloud resources are only accessed by the authorized tenants who are willing to pay. On the other hand, tenants wish to protect their personalized service access patterns, identity privacy information and accessing newfangled cloud services by on-demand ways within the scope of their permissions. There are many identity authentication and access control schemes to address these challenges to some degree, however, there are still some limitations. In this paper, we propose a new comprehensive approach, called Privacy p Reserving Identity and Access Management scheme, referred to as PRIAM, which is able to satisfy all the desirable security requirements in cloud computing. The main contributions of the proposed PRIAM scheme are threefold. First, it leverages blind signature and hash chain to protect tenant's identity privacy and implement secure mutual authentication. Second, it employs the service-level agreements to provide flexible and on-demand access control for both tenants and cloud services. Third, it makes use of the BAN logic to formally verify the correctness of the proposed protocols. As a result, our proposed PRIAM scheme is suitable to cloud computing thanks to its simplicity, correctness, low overhead, and efficiency. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
910. Lifelong accumulation of bone in mice lacking Pten in osteoblasts.
- Author
-
Ximeng Liu, Bruxvoort, Katia J., Zylstra, Cassandra R., Jiarong Liu, Cichowski, Rachel, Faugere, Marie-Claude, Bouxsein, Mary L., Chao Wan, Williams, Bart O., and Clemens, Thomas L.
- Subjects
- *
BONE growth , *GROWTH factors , *PHOSPHOINOSITIDES , *APOPTOSIS , *PEPTIDES , *TUMOR suppressor genes - Abstract
Bone formation is carried out by the osteoblast, a mesenchymal cell whose lifespan and activity are regulated by growth factor signaling networks. Growth factors activate phosphatidylinositol 3-kinase (P13K), which enhances cell survival and antagonizes apoptosis through activation of Akt/PKB. This process is negatively regulated by the Pten phosphatase. which inhibits the activity of PI3K. In this study, we investigated the effects of Akt activation in bone in vivo by conditionally disrupting the Pten gene in osteoblasts by using Cre-mediated recombination. Mice deficient in Pten in osteoblasts were of normal size but demonstrated a dramatic and progressively increasing bone mineral density throughout life. In vitro osteoblasts lacking Pten differentiated more rapidly than controls and exhibited greatly reduced apoptosis in association with markedly increased levels of phosphorylated Akt and activation of signaling pathways downstream of activated Akt. These findings support a critical role for this tumor-suppressor gene in regulating osteobtast lifespan and likely explain the skeletal abnormalities in patients carrying germ-line mutations of PTEN. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
911. In situ electrochemical oxidation of electrodeposited Ni-based nanostructure promotes alkaline hydrogen production.
- Author
-
Yajun Pang, Yong Yu, Hao Chen, Guangqing Xu, Linqing Miao, Ximeng Liu, Zhenghui Pan, Zongkui Kou, Yucheng Wu, and John Wang
- Subjects
HYDROGEN evolution reactions ,HYDROGEN production ,OXYGEN evolution reactions ,PRECIOUS metals ,OXIDATION ,ENERGY conversion ,ALKALINE solutions ,CHARGE transfer - Abstract
Highly active and stable electrocatalysts based on non-precious metals for hydrogen evolution reaction (HER) in alkaline solution are urgently required for enabling mass production of clean hydrogen in industry. Herein, core–shell NiOOH/Ni nanoarchitectures supported on the conductive carbon cloth have been successfully prepared by a facile electrodeposition process of Ni, and a subsequent in situ electrochemical oxidation. When explored as an alkaline HER electrocatalyst, the as-synthesized NiOOH/Ni nanoarchitecture requires only a low overpotential of ∼111 mV to attain a current density of −10 mA cm
−2 , demonstrating its strong catalytic capability of hydrogeneration. The excellent HER activity could well be attributed to the decreasing charge transfer resistance and competitive electrochemical active area of the amorphous NiOOH, compared with inactive Ni substrate. The feasible methodology established in this study can be easily expanded to obtain a series of nano-sized metal oxyhydroxide materials for various energy conversion and storage applications, where Ni-based nanomaterials are among the highly active ones. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
912. Watermarking in Secure Federated Learning: A Verification Framework Based on Client-Side Backdooring.
- Author
-
WEN YUAN YANG, SHUO SHAO, YUE YANG, XIYAO LIU, XIMENG LIU, ZHIHUA XIA, SCHAEFER, GERALD, and HUI FANG
- Subjects
- *
FEDERATED learning , *COPYRIGHT , *WATERMARKS , *DIGITAL watermarking , *AMBIGUITY , *DEEP learning , *INFORMATION sharing - Abstract
Federated learning (FL) allows multiple participants to collaboratively build deep learning (DL) models without directly sharing data. Consequently, the issue of copyright protection in FL becomes important since unreliable participants may gain access to the jointly trained model. Application of homomorphic encryption (HE) in a secure FL framework prevents the central server from accessing plaintext models. Thus, it is no longer feasible to embed the watermark at the central server using existing watermarking schemes. In this article, we propose a novel client-side FL watermarking scheme to tackle the copyright protection issue in secure FL with HE. To the best of our knowledge, it is the first scheme to embed the watermark to models under a secure FL environment. We design a black-box watermarking scheme based on client-side backdooring to embed a pre-designed trigger set into an FL model by a gradient-enhanced embedding method. Additionally, we propose a trigger set construction mechanism to ensure that the watermark cannot be forged. Experimental results demonstrate that our proposed scheme delivers outstanding protection performance and robustness against various watermark removal attacks and ambiguity attack. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
913. Federated Clique Percolation for Privacy-preserving Overlapping Community Detection.
- Author
-
KUN GUO, WENZHONG GUO, ENJIE YE, YUTONG FANG, JIACHEN ZHENG, XIMENG LIU, and KAI CHEN
- Subjects
- *
PERCOLATION , *BIOLOGICAL networks , *BIOMOLECULES , *INFECTIOUS disease transmission , *SOCIAL networks - Abstract
Community structure is a typical characteristic of complex networks. Finding communities in complex networks has many important applications, such as the advertisement and recommendation based on social networks and the discovery of new protein molecules in biological networks, which make it a hot topic in the field of complex network analysis. With the increasing concerns about the leakage of personal privacy, discovering communities spread across the local networks owned by multiple participants accurately while preserving each participant's privacy has become an emerging challenge in distributed community detection. In this article, we propose a general federated graph learning model for privacy-preserving distributed graph learning and develop two federated clique percolation algorithms (CPAs) based on it to discover overlapping communities distributed across multiple participants' local networks without disclosing any participant's network privacy. Homomorphic encryption and hash operation are used in combination to protect the privacy of the vertices and edges of each local network. Furthermore, vertex attributes are involved in the calculation of clique similarity and clique percolation when dealing with attributed networks. The experimental results on real-world and artificial datasets demonstrate that the proposed algorithms achieve identical results to those of their stand-alone counterparts and more than 200% higher accuracy than the simple distributed CPAs without federating learning. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
914. Network security of the National Natural Science Foundation of China: today and prospects
- Author
-
Dong LI, Yanni HAO, Shenghui PENG, Ruijie ZI, Ximeng LIU
- Subjects
information construction ,network security ,natural science fund ,big data ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
The National Natural Science Foundation of China (hereinafter referred to as the Natural Science Foundation of China) is responsible for effectively utilizing the National Natural Science Foundation of China, supporting basic research, adhering to free exploration, playing a guiding role, and discovering and cultivating science and technology in accordance with the national guidelines, policies and plans for the promotion of scientific and technological progress and coordinated economic and social development.With the continuous development of new productive forces represented by information technology, the Natural Science Foundation of China has been committed to promoting the informatization and intelligence of fund management.With the increasing complexity of business types, various types of network attacks, such as information leakage attacks, are encountered in the construction of informatization and make network security face severe challenges.The network security construction of the Natural Science Foundation of China was took as the main line and the network security construction of the existing platform was introduced.At present, a network security system structure with the science fund project management as the core has been established to ensure the safe and stable operation of the network system.The main information systems of the Natural Science Foundation of China (Natural Science Foundation Shared Service Network, business department website, email system) and its main threats were analyzed and introduced.Then the thoughts and suggestions in the follow-up informatization and network security construction were given.The Natural Science Foundation of China will start the construction of a new generation of secure network.Under the premise of fully considering the characteristics of science fund review, management, and open sharing, it will achieve the overall goal of “smarter, safer, and better” and carry out network security system construction for relevant units.
- Published
- 2022
- Full Text
- View/download PDF
915. Expression and occupancy of BAFF‐R on B cells in systemic lupus erythematosus.
- Author
-
Robert H. Carter, Hong Zhao, Ximeng Liu, Marc Pelletier, Winn Chatham, Robert Kimberly, and Tong Zhou
- Subjects
B cells ,LYMPHOCYTES ,SYSTEMIC lupus erythematosus ,IMMUNOGLOBULINS ,THERAPEUTICS - Abstract
To determine whether receptors for B lymphocyte stimulator (BLyS) are altered on B cells of patients with systemic lupus erythematosus (SLE).Total available receptors for BLyS were measured by analysis of binding of recombinant soluble BLyS to peripheral blood B cells in 36 SLE patients, 29 healthy controls, and 10 disease controls. Antibodies to the receptors BAFF‐R, BCMA, and TACI were used to define expression of the individual BLyS receptors on subsets of B cells in blood, spleen, and tonsils. Two different antibodies to BAFF‐R, which were differentially sensitive to BAFF‐R occupancy, were used to compare BAFF‐R on B cells in an additional 20 healthy subjects and 25 SLE patients. Assays of B cell survival after stimulation in vitro were used to determine the sensitivity of B cells to exogenous BLyS.Total available receptors for BLyS were decreased in patients with SLE, independent of changes of subsets in the blood in these patients. The decrease correlated with changes in disease activity. Although total surface BAFF‐R was not significantly different between healthy controls and SLE patients, BAFF‐R was occupied in SLE patients. B cells from these patients were less responsive to exogenous BLyS.BAFF‐R is consistently occupied on blood B cells in SLE. Occupancy of BAFF‐R on blood B cells is likely to contribute to disease mechanisms in SLE and could serve as a biomarker of disease activity. Targeting BLyS as a therapeutic strategy will require overcoming the persistent binding of BLyS to BAFF‐R. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
916. Loss of ATF4 leads to functional aging-like attrition of adult hematopoietic stem cells.
- Author
-
Yan Sun, Xiaolin Lin, Bangdong Liu, Yaxuan Zhang, Wei Li, Sheng Zhang, Falian He, Han Tian, Xun Zhu, Ximeng Liu, Jueheng Wu, Junchao Cai, and Mengfeng Li
- Subjects
- *
HEMATOPOIESIS , *HEMATOPOIETIC stem cells , *AGING , *MEDICAL sciences , *RETROVIRUS diseases - Abstract
The article presents a study that explores the loss of activating transcription factor 4 (ATF4) leads to functional aging-like attrition of adult hematopoietic stem cells . It mentions that aging of hematopoietic stem cells (HSCs) directly contributes to dysfunction of hematopoietic and immune systems due to aging-associated alterations in HSC features.
- Published
- 2021
- Full Text
- View/download PDF
917. The hypoxia-inducible factor α pathway couples angiogenesis to osteogenesis during skeletal development.
- Author
-
Ying Wang, Chao Wan, Lianfu Deng, Ximeng Liu, Xuemei Cao, Gilbert, Shawn R., Bouxsein, Mary L., Faugere, Marie-Claude, Guldberg, Robert E., Gerstenfeld, Louis C., Haase, Volker H., Johnson, Randall S., Schipani, Ernestina, and Clemens, Thomas L.
- Subjects
- *
HYPOXEMIA , *NEOVASCULARIZATION , *BONE growth , *BLOOD-vessel development , *MUSCULOSKELETAL system , *CELL migration - Abstract
Skeletal development and turnover occur in close spatial and temporal association with angiogenesis. Osteoblasts are ideally situated in bone to sense oxygen tension and respond to hypoxia by activating the hypoxia-inducible factor (HIF) pathway. Here we provide evidence that HIF promotes angiogenesis and osteogenesis by elevating VEGF levels in osteoblasts. Mice overexpressing HIF in osteoblasts through selective deletion of the von HippelLindau gene (Vhl) expressed high levels of Vegf and developed extremely dense, heavily vascularized long bones. By contrast, mice lacking Hif1a in osteoblasts had the reverse skeletal phenotype of that of the Vhl mutants: long bones were significantly thinner and less vascularized than those of controls. Loss of Vhl in osteoblasts increased endothelial sprouting from the embryonic metatarsals in vitro but had little effect on osteoblast function in the absence of blood vessels. Mice lacking both Vhl and Hif1a had a bone phenotype intermediate between those of the single mutants, suggesting overlapping functions of HIFs in bone. These studies suggest that activation of the HIF pathway in developing bone increases bone modeling events through cell-nonautonomous mechanisms to coordinate the timing, direction, and degree of new blood vessel formation in bone. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.