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We developed an in vitro DNA detection system using a pair of dCas9 proteins linked to split halves of luciferase. Luminescence was induced upon colocalization of the reporter pair to a ∼44 bp target sequence defined by sgRNAs. We used the system to detect Mycobacterium tuberculosis DNA with high specificity and sensitivity. The reprogrammability of dCas9 was further leveraged in an array design that accesses sequence information across the entire genome.

Software-defined networking (SDN) scheme decouples network control plane and data plane, which can improve the flexibility of traffic management in networks. OpenFlow is a promising implementation instance of SDN scheme and has been applied to enterprise networks and data center networks in practice. However, it has less effort to spread SDN control scheme over the Internet to conquer the ossification of inter-domain routing. In this paper, we further innovate to the SDN inter-domain routing inspired by the OpenFlow protocol. We apply SDN flow-based routing control to inter-domain routing and propose a fine-granularity inter-domain routing mechanism, named SDI (Software Defined Inter-domain routing). It enables inter-domain routing to support the flexible routing policy by matching multiple fields of IP packet header. We also propose a method to reduce redundant flow entries for inter-domain settings. And, we implement a prototype and deploy it on a multi-domain testbed.

Circadian rhythms may influence the pharmacokinetics of drugs. This study aimed to investigate the pharmacokinetic characteristics of gefitinib at different dosing times and the underlying mechanisms. The Balb/c nude mice were housed under a constant 12 h light/dark cycle (lights period 7:00 to 19:00) with food and water available ad libitum. The tumor-bearing nude mice model was established and all the mice were randomly divided into six groups and gavaged with gefitinib. The plasma and liver tissues were obtained for pharmacokinetics analysis and used to examine the mRNA expression of metabolic enzymes and its upstream signal. AUC(0–24 h) and MRT(0–24 h) of 1 h and 17 h after light onset (HALO) gefitinib groups were higher. Clearance (CL) in 1 and 17 HALO gefitinib groups were lower and the highest was found in 9 and 13 HALO gefitinib groups. The mRNA expressions of Cyp3a11, Cyp3a13, pregnenolone X receptor (PXR), constitutive androstane receptor (CAR) and brain and muscle ARNT-like-1 (Bmal1) were higher during the late light phase and the early dark phase, while the mRNA expressions of period 1 (Per 1) and period 2 (Per 2) were lower in the same time. These results show that the pharmacokinetic characteristics of gefitinib have significant circadian rhythms, which may be correlated with rhythmic expressions of metabolic enzymes and their upstream signal. This study may provide experimental evidences for clinical pharmacological research.

Currently, the architecture of network device is closed. This is detrimental to the network innovation. Software defined networking (SDN) (McKeown 2009) decouples the vertically coupled architecture, and reconstructs the Internet as a modular structure. The idea of SDN is widely accepted by both of the academic and industry researchers, and is considered as a promising way to re-architect the Internet. OpenFlow as a typical instance of the SDN has been deployed by many universities and research institutions all over the world. However, the research and technologies on transitioning the existing networks to SDN are not mature. So this paper takes the instance OpenFlow for example and proposes a simple and practical Border Gateway Protocol (BGP) based transition solution named BTSDN. BTSDN fully explores the characteristics of OpenFlow network, proposes to continue using the current BGP protocol, and retains the legacy BGP border routers to connect the OpenFlow network with the rest of Internet. The experiment at the end of this paper preliminary verifies the feasibility of BTSDN.

Chronic exposure to trichothecenes is known to disturb insulin-like growth factor 1 and signaling of insulin and leptin hormones and causes considerable growth retardation in animals. However, limited information was available on mechanisms underlying trichothecene-induced growth retardation. In this study, we employed an integrated transcriptomics, proteomics, and RNA interference (RNAi) approach to study the molecular mechanisms underlying trichothecene cytotoxicity in rat pituitary adenoma GH3 cells. Our results showed that trichothecenes suppressed the synthesis of growth hormone 1 (Gh1) and inhibited the eukaryotic transcription and translation initiation by suppressing aminoacyl-tRNA synthetases transcription, inducing eukaryotic translation initiation factor 2-alpha kinase 2 (EIF2AK2) and reducing eukaryotic translation initiation factor 5 a. The sulfhydryl oxidases , protein disulfide isomerase,and heat shock protein 90 (were greatly reduced, which resulted in adverse regulation of protein processing and folding. Differential genes and proteins associated with a decline in energy metabolism and cell cycle arrest were also found in our study. However, use of RNAi to interfere with hemopoietic cell kinase (Hck) and EIF2AK2 transcriptions or use of chemical inhibitors of MAPK, p38, Ras, and JNK partially reversed the reduction of Gh1 levels induced by trichothecenes. It indicated that the activation of MAPKs, Hck, and EIF2AK2 were important for trichothecene-induced growth hormone suppression. Considering the potential hazards of exposure to trichothecenes, our findings could help to improve our understanding regarding human and animal health implications.

SDN [1] is considered to be a promising way to re-architect the Internet. However, the Internet is managed by owners of different administrative domains, so the centralized control model of SDN must be extended to account for inter-domain traffic. Thus, this article proposes a WE-Bridge mechanism to enable different SDN administrative domains to peer and cooperate. Based on WE-Bridge, we further designed two innovative inter-domain routing applications as use cases. To verify our design, we implemented the WE-Bridge and the two use cases by building an international testbed on which WE-Bridge, together with the two use cases, are deployed. The testbed is composed of four SDN networks: CERNET, Internet 2 in USA, CSTNET, and SURFnet.

Large networks are often partitioned by the network operators into several smaller networks when deploying software-defined networks SDNs. Additionally, a dedicated network operating system NOS is deployed for each of these SDNs. Each NOS can learn the local network view that enables control of how data packets are forwarded within its network. Controlling the flow of data packets in an entire network requires each NOS to have a global network view to determine the next NOS hop. Hence, NOSes are required to share or exchange reachability and topological information. How such information is efficiently exchanged has not been well addressed so far, especially in the case of multi-vendor NOSes. This paper proposes a west-east bridge mechanism for distributed heterogeneous NOSes to cooperate in enterprise/data center/intra-autonomous system networks. We propose to simplify physical networks into virtual networks and only exchange the simplified virtual network information to construct the global network view. To achieve a resilient peer-to-peer control plane of distributed heterogeneous NOSes, we propose a "maximum connection degree"-based connection algorithm. Considering the security issue, we adopt controller identity authentication. We implement the west-east bridge and analyze the performance obtained: about 100% of enterprises and data centers, and about 99.5% of autonomous systems can adopt to this solution. The deployment in three SDNs CERNET, Internet2, and CSTNET proves the feasibility. Copyright © 2014 John Wiley & Sons, Ltd.

Nanoparticles of amphiphilic triblock copolymer poly(l-lysine)-b-poly(ethylene glycol)-b-poly(l-lysine) and diblock copolymer methoxy-poly(ethylene glycol)-b-poly(l-lysine) were developed to encapsulate tetra(4-sulfoazophenyl-4′-aminosulfonyl) chloride aluminum phthalocyanine, a new photosensitizer used in photodynamic therapy. The mean nanoparticle sizes varied from 10 to 70 nm, and the encapsulation efficacy ranged from 56 to 73 % due to electrostatic self-assembly induced by two types of polymer. The characteristic photophysical parameters including the absorption spectrum profile, fluorescence quantum yield, and fluorescence decay curves for free and encapsulated phthalocyanine were analyzed. The cellular uptake amount and photoactivity of S-AlPc were improved by encapsulation. The aluminum phthalocyanine loaded with poly(l-lysine)-b-poly(ethylene glycol)-b-poly(l-lysine) presented suitable physical stability, improved photophysical properties, and enhanced phototoxicity in vitro, suggesting it may be considered as a promising formulation for PDT.

The binding interaction between tetra-(p-sulfoazophenyl-4-aminosulfonyl)-substituted aluminum (III) phthalocyanine (AlPc), and two-serum albumins (bovine serum albumin (BSA) and human serum albumin (HSA)) has been investigated. AlPc could quench the intrinsic fluorescence of BSA and HSA through a static quenching process. The primary and secondary binding sites of AlPc on BSA were domain I and III of BSA. The primary binding site of AlPc on HSA was domain I, and the secondary binding sites of AlPc on HSA were found at domains I and II. Our results suggest that AlPc readily interact with BSA and HSA implying that the amphiphilic substituents AlPc may contribute to their transportation in the blood.

Serum albumin, the most abundant plasma protein in mammalian blood, shows significant effects on delivery and therapeutic efficacy of drugs, therefore, the investigation of binding interaction between serum albumin and drugs is vital and necessary. In the present study, the binding interaction of two aluminum (III) phthalocyanine (AlPc) derivatives, tetrasulfonate- and tetra-(p-sulfoazophenyl-4-aminosulfonyl)-substituted AlPc (complexes 1 and 2), with bovine serum albumin (BSA) was investigated by UV-Vis and fluorescence spectroscopy. Adding BSA to the Pc complexes in water caused remarkable changes in the Q-band of the Pc complexes, indicating an altered aggregation behavior. When titrating these AlPcs with BSA in PBS, the intrinsic fluorescence of BSA was significantly quenched through a static quenching process. The binding of Pc complexes to BSA might change its conformation, evidenced by the red shift of maximum emission wavelength. Furthermore, binding constants and binding sites were obtained and binding ability between the Pc complexes and BSA was assessed. Our results suggest that complexes 1 and 2 readily interact with BSA whereas the latter shows more affinity (with higher binding constant value) to BSA, implying the stretched amphiphilic substituents of complex 2 may contribute to their transportation in the blood.

The research on transiting the existing networks to SDN (Software defined networking) just starts. We propose to continue using the BGP (Border Gateway Protocol) and the legacy BGP border routers for the SDN network and connect the SDN network with legacy IP networks in this paper. The experiments we carried out preliminary proved our design.

Software defined networking (SDN) [1] works as a centralized control model. However, the Internet is managed by owners of different domains, which makes the centralized control does not work for inter-domain. Controlling the flow of data packets in a global network requires each NOS (Network Operating System) to have a relative global network view to determine the next NOS hop. Hence, NOSes are required to exchange reachability and topology information between the inter-domain networks. How such information is efficiently exchanged has not been well addressed so far. Thus, this demo proposes a West-East Bridge (WE-Bridge) mechanism for different SDN administrative domains to peer and cooperate with each other: (1) we design a peer-to-peer based high performance network information exchange mechanism. We define what network information should be exchanged and how such information is efficiently exchanged among interdomain SDN peers. (2) To achieve a resilient peer-to-peer control plane of heterogeneous NOSes, we propose a ‘maximum connection degree’ based connection algorithm [4]. (3) Considering the privacy, we propose to virtualize the SDN network view, and only exchange the virtualized network view to construct the relative global network view. Applications above WE-Bridge carry out the route translation, calculation, and installation. We deployed WE-Bridge together with two use cases to four SDN networks CERNET (China Education and Research Network), Internet2 in USA, CSTNET (China Science and Technology Network), and SURFNET (the national research and education network of Netherlands).

A novel spacer chains substituted aluminum phthalocyanine (Pc), naming tetra-carboxylaminohexanoicsulfonyl aluminium phthalocyanine 4 was synthesized. Its structure was characterized by elemental analysis, IR, 1H NMR and MS. Polyion complex micelle (PIC) between the 4 and amphiphilic triblock copolymer poly(L-lysin)-block-poly(ethylene glycol)-block-poly(L-lysin) (PLL-b-PEG-b-PLL) was formed via an electrostatic interaction between the positively charged poly(L-lysin)(PLL) segment and negatively charged periphery of the 4. Dynamic light scattering (DLS) and atom force microscopy (AFM) image showed that 4-loaded PIC formed a spherical nanocarrier micelle with approximately 85 nm in diameter. The fluorescence intensity and lifetime of 4-loaded PIC were significantly enhanced by the incorporation 4 into PIC nanocarrier. The time-dependent intracellular uptake amount and in vitro photodynamic photocytotoxicity of the 4 within the nanocarrier were drastically improved compared with the free 4.

In this paper, we proposal an content provider mobility solution of Named Data Networking (NDN) [1]. Here content provider means the host of NDN network which provide content originally.

Software Defined Networking (SDN) is considered as a promising method to re-construct the architecture of Internet. At present, the programs of network protocols are mixed together in SDN controller. However, in the production network, an isolated network environment with private resources is needed for each network protocol running on the same SDN controller. It is therefore necessary to design a practical virtualization cloud platform on the SDN network operating system (NOS). In this paper, we introduce a virtualization cloud platform for SDN production network. A prototype is implemented and two cases are performed to show the feasibility and the effectiveness of our proposed framework.

Currently, the architecture of network device is closed which is detrimental to network innovation. Software defined networking decouples the vertically coupled architecture and reconstructs the Internet as a modular structure. The idea of software defined networking is widely accepted. OpenFlow, a typical instance of the software defined networking, has been deployed by many universities and research institutions all over the world. With the increasing scale of deployment, the poor scalability of the OpenFlow centralized control mode becomes more and more obvious. To solve this scalability problem, this paper adopts the idea of load balance and proposes an architecture for the scalable intra-domain control named ASIC in OpenFlow. ASIC balances all the data flow initialization requests to several physical controllers in an OpenFlow network, and then, those requests are processed with a shared global network view in a parallel manner. ASIC also builds a data cluster for the global network view. By this way, the scalability problem in the intra-domain control plane could be completely solved. At the end of this paper, the emulation shows the feasibility of ASIC.

Currently, new protocols or architectures related to core network layer or network forwarding equipment are hard to deploy. And the core network evolves slowly. To solve this problem, various programmable Internet architectures and approaches are proposed. Programmable networks allow network researchers (not only the equipment vendors like Cisco and Juniper) to program and manage their customized architectures or protocols. This paper firstly describes the ossification with the current Internet architecture. And then it analyzes several most representative approaches for programmable networks with their mechanisms, advantages, and shortcomings. By the analysis above, this paper at last discusses the future research trends and gives a detailed description of the key issues in the future research of the programmable networks.

By means of analyzing Yong's minimax portfolio selection model, a novel risk function is introduced with risk measure considering risk and extra return factors. The risk factor can tune the effects of asset yield on the investment decision, and the extra return factor can control the effects of assets portfolio's margin on the investment decision. Furthermore, an assets portfolio optimization model is designed based on the risk function. To solve the model, it is converted to a linear programming model. With actual data of the stock market, computational experiments show that the proposed model is effective and practicable.

Based on the analysis of minimax portfolio selection model proposed by Yong, a new risk function is designed with risk factor and extra return factor. The risk factor is used to adjust the effect of asset return level on the investment decision, and the extra return factor is for controlling the effect of portfolio promising profits on the investment decision. Furthermore, a portfolio selection model is proposed based on the new risk measure. The model is solved by transforming it into a linear programming model. By experiments with actual data of the stock market, this proposed model shows its effectiveness and practicability.