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We consider a simplified version of Ericksen-Leslie equation modeling the compressible hydrodynamic flow of nematic liquid crystals in dimension one. If the initial data $(\rho_0, u_0,n_0)\in C^{1,\alpha}(I)\times C^{2,\alpha}(I)\times C^{2,\alpha}(I, S^2)$ and $\rho_0\ge c_0>0$, then we obtain both existence and uniqueness of global classical solutions. For $0\le\rho_0\in H^1(I)$ and $(u_0, n_0)\in H^1(I)\times H^2(I,S^2)$, we obtain both existence and uniqueness of global strong solutions.

In recent paper, we prove the well-posedness for the heat flow of harmonic maps with initial data and for the hydrodynamic flow of nematic liquid crystals with initial data . Copyright © 2011 John Wiley & Sons, Ltd.

The Landau–Lifshitz–Gilbert equation describes the evolution of spin fields in continuum ferromagnetics. The present paper consists of two parts. The first one is to prove the local existence of smooth solution to the Landau–Lifshitz–Maxwell systems in dimensions three. The second is to prove the finite time blow up of solutions for these systems. It states that for suitably chosen initial data, the short time smooth solutions to the Landau–Lifshitz–Maxwell equations do blow up at finite time. Copyright © 2011 John Wiley & Sons, Ltd.

This paper is concerned with a simplified hydrodynamic equation, proposed by Ericksen and Leslie, modeling the flow of nematic liquid crystals. In dimension two, we establish both interior and boundary regularity theorems for such a flow under smallness conditions. As a consequence, we establish the existence of global (in time) weak solutions on a bounded smooth domain in $${\mathbb{R}^2}$$ which are smooth everywhere with possible exceptions of finitely many singular times.

The present paper is concerned with the existence, uniqueness and singularities of the Landau–Lifshitz equation coupled with Maxwell equations on Riemannian manifold in two dimensions. It is shown that there exists a weak solution which is regular with exception of at most finitely many singular points.

This paper proposes a new approach called region mosaicing on contrast pyramids for multi-focus image fusion. A density-based region growing is developed to construct a focused region mask for multi-focus images. The segmented focused region mask is decomposed into a mask pyramid, which is then used for supervised region mosaicing on a contrast pyramid. In this way, the focus measurement and the continuity of focused regions are incorporated and the pixel level pyramid fusion is improved at the region level. Objective and subjective experiments show that the proposed region mosaicing on contrast pyramids approach is more robust to noise and can fully preserves the focus information of the multi-focus images, reducing distortions of the fused images.

With the progression of sea exploration and offshore engineering, electronic charts have come to see widespread use in many intelligent applications. Like other digital products, electronic charts are easy to duplicate and distribute. Some watermarking solutions have proven defective to prevent copying of electronic charts because it’s as easy to forge as it is to redistribute. If the problems of copyright infringement cannot be solved, the creation of these electronic charts will be limited. The most important characteristic of electronic charts is the topological relationships among vertices, but few algorithms can control this feature. A new watermarking algorithm is here proposed as a means of copyright protection, in which the watermarks will be hosted in the electronic chart by taking into account the preservation of the topology. Sometimes, additional vertices are inserted into the middle of two adjacent vertices, sometimes not, which are governed by the value of the watermark. Experiments show that the improved algorithm is better than similar algorithms; it was found to resist geometric attacks and format exchange attacks.

Motivated by \cite{JS}, we prove that there exists a global, forward self-similar solution to the viscoelastic Navier-Stokes equation with damping, that is smooth for $t>0$, for any initial data that is homogeneous of degree $-1$., 30 pages

We study the problem of broadcasting scalable video coded (SVC) streams in cellular networks, where all user equipments (UEs) require the same video content and cooperate with each other. To take the advantage of channel diversity gains, the base station (BS) uses network coding to generate linear combinations of the video packets for broadcasting in the downlink. Once receiving sufficient number of the combinations, a UE can relay packets to others via device-to-device (D2D) connections. To optimize the downlink and D2D transmission arrangement, we first formulate a mixed integer non-linear programming (MINLP) problem, which becomes difficult to solve when the number of UEs increases. Then we convert the MINLP problem to a quasi-convex optimization problem using a continuous step function, and a primal-dual decomposition approach is used to solve it in a distributed way. Simulation results show that the proposed approach achieves a near-optimal solution.

In this paper we study the model that the usual Maxwell's equations are supplemented with a constitution relation in which the electric displacement equals a constant time the electric field plus an internal polarization variable and the magnetic displacement equals a constant time the magnetic field plus the microscopic magnetization. Using the Galerkin method and viscosity vanishing approach, we obtain the existence of the global weak solution for the Landau-Lifshitz-Maxwell equations. The main difficulties in this study are due to the loss of compactness in the system.

Although many efforts have been made to study the reputation evaluation of node performance in Mobile Peer-to-Peer Networks (MP2P), the existing methodology of node reputation evaluation are not applicable to the scenarios in dynamic networks. To improve the performance of MP2P, in this study, we develop a new evaluation of node reputation by combining an analytic hierarchy process with a fuzzy comprehensive evaluation technology. The reputation of nodes is calculated using a membership function to account for direct and indirect trust, residual energy and fuzzy comprehensive evaluation. The experimental results show that the proposed method is not only robust in delivering a ratio of packet, but also reduce the average latency and overload ratio in MP2P environment.

In Distributed Virtualized Environment, service components on a dependable service path will be selected to implement service composition. Searching for the optimal dependable service path is the key to implement dependability assurance, which is a Multi-Constrained Optimal Path problem. However, the existing algorithms have disadvantages of high complexity and low performance, and lacking the consideration of trust relationships and evidence spread among service components during service construction and composition. We proposed the concept of QoD, the Quality of Dependability, introducing some attributes(e.g. component intimacy) to describe and restrict the dependable service path searching in distributed virtualized environment. We also applied Adaptive Bonus-Penalty Micro-canonical Annealing(ABP-MA) to dependable service path searching, and chose service components on the optimal dependable service path to satisfy users' demands for service dependability. The experimental results showed that ABP-MA has the advantages of fast convergence and high search success rate.

Ambient noise and variation of illumination intensity can severely degrade the performance of the structured light sensor. To overcome these noises, we present a robust algorithm based on adaptive monochromatic space and minimum entropy model for the laser stripe segmentation in the structured light image. The proposed method not only makes high accuracy segmentation of the laser stripe, but also keeps the smoothness of the stripe. Experimental results show that the algorithm has great improvement to four classical algorithms.

Using the differential–difference method and viscosity vanishing approach, we obtain the existence and uniqueness of the global smooth solution to the periodic initial-value problem of the inhomogeneous, non-automorphic Landau–Lifshitz equation without Gilbert damping terms in one dimension. To establish the uniform estimates, we use some identities resulting from the fact and the fact that the vectors form an orthogonal base of the space .

In Cloud Computing, the application software and the databases are moved to large centralized data centers, where the management of the data and services may not be fully trustworthy. This unique paradigm brings many new security challenges, which have not been well solved. Data access control is an effective way to ensure the big data security in the cloud. In this paper, we study the problem of fine-grained data access control in cloud computing. Based on CP-ABE scheme,we propose a novel access control policy to achieve fine-grainedness and implement the operation of user revocation effectively. The analysis results indicate that our scheme ensures the data security in cloud computing and reduces the cost of the data owner significantly.

Web services is one of the basic network services, whose availability evaluation is of great significance to the promotion of users’ experience. This paper focuses on the problem of availability evaluation of Web services and proposes a method for availability evaluation of Web services using improved grey correlation analysis with entropy difference and weight (EWGCA).This method is based on grey correlation analysis, and use entropy difference to illustrate the changes of availability, set weight to quantize availability requirements of different operations or transactions in services. Through simulation experiment in high load scenarios for Web services, the experiment result shows that our method can realize hierarchical description and overall evaluation for availability of Web services accurately in the case of smaller test sample volumes or uncertain data even in the field of big data.

First, this paper gives a metric to quantify interference level among multiple routing paths in wireless sensor networks. Unlike the existing metrics, the proposed one can precisely measure interference level among any set of paths, even though these paths have some nodes or links in common. Based on the proposed metric, the Minimizing-Interference-for-Multiple-Paths MIMP problem is considered: Given k routing requests $$\{s_1, t_1\}, \dots , \{s_k, t_k\}$${s1,t1},i¾?,{sk,tk}, find k paths connecting these routing requests with minimum interference. The MIMP problem is NP-hard even for $$k=2$$k=2. This paper proposes heuristic distributed on-line algorithm for the MIMP problem. The efficiency of the proposed algorithm is verified by simulation results.

Most of existed strategies for defending OFA (Objective Function Attack)are centralized, only suitable for small-scale networks and stressed on the computation complexity and traffic load are usually neglected. In this paper, we pay more attentions on the OFA problem in large-scale cognitive networks, where the big data generated from the network must be considered and the traditional methods could be of helplessness. In this paper, we first analyze the interactive processes between attacker and defender in detail, and then a defense strategy for OFA based on differential game is proposed, abbreviated as DSDG. Secondly, the game saddle point and optimal defense strategy have proved to be existed simultaneously. Simulation results show that the proposed DSDG has a less influence on network performance and a lower rate of packet loss.More importantly, it can cope with the large range OFA effectively.

Exceptions are those abnormal data flow which needs additional calculation to deal with. Exception analysis concerned abnormal flow contains a lot of research content, such as exception analysis method, program verification. This article introduces another research direction of exception analysis which based on formal method. The article analyses and summarizes those research literatures referring exception analysis and exception handling logic verification based on formal reasoning and model checking. In the article, we provide an overview of the relationship and difference between traditional ideas and formal method concerning program exception analysis. In the end of the article, we make some ideas about exception analysis based on formal semantic study of procedure calls. Exception handling is seen as a special semantic effect of procedures calls.

Wireless networks generate large amount of data. It is important to design energy efficient data search method since power of wireless nodes is finite. Expanding Ring Search (ERS) is a data search technique exploring for targets progressively, which is widely used to locate destinations or information in wireless networks. The existing studies on improving the energy efficiency of ERS cannot work without positioning systems. In this paper, we combine the technique of random walk with ERS, and propose a random walk based expanding ring search method (RWERS) for large-scale wireless networks. RWERS can work without using positioning systems, and improve the energy efficiency of ERS by preventing each node from transmitting the same request more than once using the technique of random walk. We compare RWERS with the optimal ERS strategy and CERS in networks with various shapes of terrains. The simulation results show that RWERS decreases the energy cost by 50% without decreasing in success rate compared with ERS, and has twice the success rate of CERS when the network is sparse. RWERS can be applied to various shapes of terrains better compared with CERS.

Non-targeted mutagenesis studies of the yeast K + channel, TOK1, have led to identification of functional domains common to other cation channels as well as those so far not found in other channels. Among the latter is the ability of the carboxyl tail to prevent channel closure. Here, we show that the tail can fulfill this function in trans . Coexpression of the carboxyl tail with the tail-deleted channel core restores normal channel behavior . A Ser/Thr-rich region at its amino end and an acidic stretch at its carboxyl end delineate the minimal region required for tail function. This region of 160 aa apparently forms a discrete functional domain. Interaction of this domain with the channel core is strong, being recalcitrant to removal from excised membrane patches by both high salt and reducing agents. Although the use of a cytoplasmic domain to regulate channel is common among animal channels, by using it as a “foot-in-the-door” to maintain open state appears unique to TOK1, the first fungal K + channel studied in depth.

We study the problem of transmitting scalable video coded streams in a hybrid scenario including a global cellular network and a local peer-to-peer network. Given desirable channel condition in cellular downlink, some cellular user equipments can fetch the video chunks via the cellular base station directly, and also provide relay service via the local peer-to-peer network for other user equipments unable to meet their basic video quality. To take the advantage of channel diversity gains, the method of random linear coding is adopted to generate linear combinations of the video chunks for transmission in both the cellular and peer-to-peer networks. To optimize the cellular and peer-to-peer transmission arrangement, we first formulate it as a mixed integer nonlinear programming problem, which becomes more complicated when the number of user equipments increases. Then, we convert it to a quasi-convex optimization problem by approximating the indicator function with a continuous step function, and it can be solved by a centralized approach. Furthermore, a primal-dual decomposition approach is developed and a distributed algorithm is proposed accordingly. Simulation results show that the proposed approach achieves a near-optimal solution.

Future networks devoted much attention to QoS of user experience. This makes it very important to understand the characteristics of user traffic. For network across multiple network layers have the characteristics of varying complexity, put forward a kind of traffic characteristics analysis method based on space and time scales. Firstly, the traffic model is established using multi-scale characterization, and then network behavior at different temporal and spatial scales of structural complexity network behavior is analyzed. Then we explore its change law of time scale, it can success classifies traffic types, so as to accurately forecast the next period of time of business. The results of the experiment data analysis shows that the method can effectively realize online monitoring of the business flow.

In this paper, we consider the initial and boundary value problem of a simplified compressible nematic liquid crystal flow in $\Omega\subset\mathbb R^3$. We establish the existence of global weak solutions, provided the initial orientational director field $d_0$ lies in the hemisphere $\mathbb S^2_+$., Comment: 27 pages

In wireless sensor networks, routing messages through multiple (node) disjoint paths between two sensor nodes is a promising way to increase robustness, throughput, and load balance. This paper proposes an efficient distributed algorithm named distributedly finding disjoint paths (DFDP) to find k disjoint paths connecting two given nodes s and t. A set of paths connecting s and t are disjoint if any two of them do not have any common nodes except s and t. Unlike the existing distributed algorithms, DFDP guarantees correctness; that is, it will output k disjoint paths if there exist k disjoint paths in the network or the maximum number of disjoint paths otherwise. Compared with the centralized algorithms which also guarantee correctness, DFDP is shown to have much better efficiency and load balance by theory analysis and simulation results.

The rare diseases ataxia-telangiectasia (AT), caused by mutations in the ATM gene, and Nijmegen breakage syndrome (NBS), with mutations in the p95/nbs1 gene, share a variety of phenotypic abnormalities such as chromosomal instability, radiation sensitivity and defects in cell-cycle checkpoints in response to ionizing radiation1,2,3,4. The ATM gene encodes a protein kinase that is activated by ionizing radiation or radiomimetic drugs5,6, whereas p95/nbs1 is part of a protein complex that is involved in responses to DNA double-strand breaks3,7. Here, because of the similarities between AT and NBS, we evaluated the functional interactions between ATM and p95/nbs1. Activation of the ATM kinase by ionizing radiation and induction of ATM-dependent responses in NBS cells indicated that p95/nbs1 may not be required for signalling to ATM after ionizing radiation. However, p95/nbs1 was phosphorylated on serine 343 in an ATM-dependent manner in vitro and in vivo after ionizing radiation. A p95/nbs1 construct mutated at the ATM phosphorylation site abrogated an S-phase checkpoint induced by ionizing radiation in normal cells and failed to compensate for this functional deficiency in NBS cells. These observations link ATM and p95/nbs1 in a common signalling pathway and provide an explanation for phenotypic similarities in these two diseases.

Satellite cells are the chief contributor to skeletal muscle growth and regeneration. The study of mouse satellite cells has accelerated in recent years due to technical advancements in the isolation of these cells. The study of human satellite cells has lagged and thus little is known about how the biology of mouse and human satellite cells compare. We developed a flow cytometry-based method to prospectively isolate human skeletal muscle progenitors from the satellite cell pool using positive and negative selection markers. Results show that this pool is enriched in PAX7 expressing cells that possess robust myogenic potential including the ability to give rise to de novo muscle in vivo. We compared mouse and human satellite cells in culture and identify differences in the elaboration of the myogenic genetic program and in the sensitivity of the cells to cytokine stimulation. These results indicate that not all mechanisms regulating mouse satellite cell activation are conserved in human satellite cells and that such differences may impact the clinical translation of therapeutics validated in mouse models. Thus, the findings of this study are relevant to developing therapies to combat muscle disease.

The hepatitis B virus (HBV) is a DNA virus that can cause chronic hepatitis B (CHB) in humans. Current therapies for CHB infection are limited in efficacy and do not target the pre-existing viral genomic DNA, which are present in the nucleus as a covalently closed circular DNA (cccDNA) form. The transcription activator-like (TAL) effector nucleases (TALENs) are newly developed enzymes that can cleave sequence-specific DNA targets. Here, TALENs targeting the conserved regions of the viral genomic DNA among different HBV genotypes were constructed. The expression of TALENs in Huh7 cells transfected with monomeric linear full-length HBV DNA significantly reduced the viral production of HBeAg, HBsAg, HBcAg, and pgRNA, resulted in a decreased cccDNA level and misrepaired cccDNAs without apparent cytotoxic effects. The anti-HBV effect of TALENs was further demonstrated in a hydrodynamic injection-based mouse model. In addition, an enhanced antiviral effect with combinations of TALENs and interferon-α (IFN-α) treatment was observed and expression of TALENs restored HBV suppressed IFN-stimulated response element-directed transcription. Taken together, these data indicate that TALENs can specifically target and successfully inactivate the HBV genome and are potently synergistic with IFN-α, thus providing a potential therapeutic strategy for treating CHB infection.

The role of hepatocyte nuclear factor 1α (HNF1α) in the regulation of gene expression and replication of hepatitis B virus (HBV) is not fully understood. Previous reports have documented the induction of the expression of viral large surface protein (LHBs) by HNF1α through activating viral Sp1 promoter. Large amount of LHBs can block the secretion of hepatitis B surface antigen (HBsAg). Here we found that HNF1α overexpression inhibited HBV gene expression and replication in Huh7 cells, resulting in marked decreases in HBsAg, hepatitis B e antigen (HBeAg) and virion productions. In contrast, knockdown of endogenous HNF1α expression enhanced viral gene expression and replication. This HNF1α-mediated inhibition did not depend on LHBs. Instead, HNF1α promoted the expression of NF-κB p65 and slowed p65 protein degradation, leading to nuclear accumulation of p65 and activation of the NF-κB signaling, which in turn inhibited HBV gene expression and replication. The inhibitor of the NF-κB signaling, IκBα-SR, could abrogate this HNF1α-mediated inhibition. While the dimerization domain of HNF1α was dispensable for the induction of LHBs expression, all the domains of HNF1α was required for the inhibition of HBV gene expression. Our findings identify a novel role of HNF1α in the regulation of HBV gene expression and replication.

Cognitive network has a cognitive process that can perceive current network conditions, and then plan, decide and act on those conditions. The network can learn from these adaptations and use them to make future decisions, all while taking into account end-to-end goals. This paper has laid the groundwork for the basic infrastructure of a cognitive network and has proposed a method for the multiple access selection. Additionally, the cognitive network access management framework has been proposed with the consideration of cross-layer design. Finally, a cognitive network access selection algorithm has been proposed based on the D-S evidence theory. We have designed a simulation experiment and compared our proposed algorithm with other network access selection methods. The experiment results showed that our method can detect the states of multiple access channels effectively and then compute the access priority based on the evidence.

Self-destruction technology is very important to protect privacy information and is the ultimate means for information security. To achieve self-destruction of distributed system, a hierarchical self-destruction system model is established. Based on rough set theory, self-destructive conditions are determined and self-destruction realization method is designed based on components. At last, self-destruction process is analyzed combined with application examples. The results show that the method can self-destruct distributed system effectively and the self-destructed part can not be recovered. Self-destruction correctness and time-efficiency is higher, which has good feasibility and practicality

Nijmegen breakage syndrome (NBS) is a rare autosomal recessive disorder characterized by microcephaly, immunodeficiency, and predisposition to hematopoietic malignancy [1]. The clinical and cellular phenotypes of NBS substantially overlap those of ataxia-telangiectasia (A-T). NBS is caused by mutation of the NBS1 gene, which encodes a member of the Mre11 complex [2, 3], a trimeric protein complex also containing Mre11 and Rad50 [4]. Several lines of evidence indicate that the ataxia-telangiectasia mutated (ATM) kinase and the Mre11 complex functionally interact [5]. Both NBS and A-T cells exhibit ionizing radiation (IR) sensitivity and defects in the intra S phase checkpoint, resulting in radioresistant DNA synthesis (RDS)—the failure to suppress DNA replication origin firing after IR exposure [6]. NBS1 is phosphorylated by ATM in response to IR, and this event is required for activation of the intra S phase checkpoint (the RDS checkpoint) [7–10]. We derived a murine model of NBS, the Nbs1 ΔB/ΔB mouse. Nbs1 ΔB/ΔB cells are phenotypically identical to those established from NBS patients. The Nbs1 ΔB allele was synthetically lethal with ATM deficiency. We propose that the ATM-Mre11 complex DNA damage response pathway is essential and that ATM or the Mre11 complex serves as a nexus to additional components of the pathway.

The molecular identification of ion channels in internal membranes has made scant progress compared with the study of plasma membrane ion channels. We investigated a prominent voltage-dependent, cation-selective, and calcium-activated vacuolar ion conductance of 320 pS (yeast vacuolar conductance, YVC1) in Saccharomyces cerevisiae . Here we report on a gene, the deduced product of which possesses significant homology to the ion channel of the transient receptor potential (TRP) family. By using a combination of gene deletion and re-expression with direct patch clamping of the yeast vacuolar membrane, we show that this yeast TRP -like gene is necessary for the YVC1 conductance. In physiological conditions, tens of micromolar cytoplasmic Ca 2+ activates the YVC1 current carried by cations including Ca 2+ across the vacuolar membrane. Immunodetection of a tagged YVC1 gene product indicates that YVC1 is primarily localized in the vacuole and not other intracellular membranes. Thus we have identified the YVC1 vacuolar/lysosomal cation-channel gene. This report has implications for the function of TRP channels in other organisms and the possible molecular identification of vacuolar/lysosomal ion channels in other eukaryotes.