Plinabulin (11, NPI-2358) is a potent microtubule-targeting agent derived from the natural diketopiperazine "phenylahistin" (1) with a colchicine-like tubulin depolymerization activity. Compound 11 was recently developed as VDA and is now under phase II clinical trials as an anticancer drug. To develop more potent antimicrotubule and cytotoxic derivatives based on the didehydro-DKP skeleton, we performed further modification on the tert-butyl or phenyl groups of 11, and evaluated their cytotoxic and tubulin-binding activities. In the SAR study, we developed more potent derivatives 33 with 2,5-difluorophenyl and 50 with a benzophenone in place of the phenyl group. The anti-HuVEC activity of 33 and 50 exhibited a lowest effective concentration of 2 and 1 nM for microtubule depolymerization, respectively. The values of 33 and 50 were 5 and 10 times more potent than that of CA-4, respectively. These derivatives could be a valuable second-generation derivative with both vascular disrupting and cytotoxic activities.

Recently, it has been noted that the inefficiencies in peer-to-peer (P2P) overlay networks result in a large quantity of traffic among internet service providers (ISPs) or autonomous systems (ASes). To optimize cross-ISP/AS traffic, the existing approaches introduce network-aware strategies in which peers select geographically close peers as neighbors using topological information. However, each P2P application must be equipped with a locality-aware neighbor-selection procedure and/or a communication protocol to obtain the topological information from an "oracle" server; i.e., modifications of P2P applications are required for this scheme. In this study, we propose a novel approach for P2P traffic localization, called P2P-DISTO, featuring the insertion of an additional delay into each P2P packet based on the geographic location of its destination. Because P2P-DISTO is implemented on network routers independently of applications, it can be utilized by all P2P applications without software modifications. The experimental evaluations using existing P2P video streaming services show that our fundamental concept successfully achieves P2P traffic localization by discouraging connections with faraway peers due to the additional delay.

In this work, an industrial Wireless Local Area Network (iWLAN) system used to control industrial robots (iRBs) in factory automation (FA) environments is addressed. For fast and deterministic communication, we propose a synchronous multi-user round-robin transmission protocol. To reduce the overhead caused by the conventional multiple downlink access, we also propose a low overhead Packet Division Multiple Access (PDMA) technique. The analysis and simulation results show that our proposals provide 100% and 300% better throughput than the conventional industrial Point Coordination Function (iPCF) and Space Division Multiple Access (SDMA) protocol schemes, respectively. In particular, with the control duration per iRB of being better than 100 µsec, the proposal completely satisfies the demand for fast control of FA systems. Furthermore, the hardware architecture of MAC layer of iWLAN system is also proposed and designed to successfully implement the proposed protocol.

In this paper, a Wireless Local Area Network (WLAN) solution for the industrial communication system utilized in the factory automation (FA) environment is addressed. In the FA field, the communication mechanism which is intended to the short frame transmissions under real-time, safety and fair distribution between the industrial robots (iRBs) is now being investigated. We offer two proposals to achieve such goals. The first proposal is an advanced round-robin iWLAN transmission protocol whose operation is strictly controlled by a precise synchronous scheduling mechanism. The second offer is a novel multiple downlink (DL) access, called Packet Division Multiple Access (PDMA) that removes significant overheads caused by traditional multiple access techniques. For protocol scheme, the analysis results show that, under safety period constraint our proposal incredibly improves the throughput as compared with that of the conventional industrial Point Coordination Function (iPCF). For multiple DL access scheme, the simulation results prove that the offered PDMA technique provides much better than conventional Space Division Multiple Access (SDMA) technique on both Packet Error Rate (PER) and throughput. Further, with the accomplishment of being better than 100 microseconds (μs) for the control duration per iRB, the proposed techniques completely satisfy the real time requirement for our FA control system.

In this paper, an industrial Wireless Local Area Network (iWLAN) solution applied to control industrial robots (iRBs) in the factory automation (FA) environment is addressed. The fast and safety are the goals of our proposed system. The first proposal is an advanced round-robin iWLAN transmission protocol whose operation is strictly controlled by a precise synchronous scheduling mechanism. The second offer is a novel multiple downlink (DL) access, called Packet Division Multiple Access (PDMA) that removes significant overheads caused by traditional multiple access techniques. The simulation results show that the proposals incredibly improve the throughput as compared with that of the conventional industrial Point Coordination Function (iPCF) and Space Division Multiple Access (SDMA) protocol schemes. Besides, our system also proves that it provides much less System Error Rate (SER), i.e. secures more safety, than those conventional ones under the same working environment. Further, with the accomplishment of being better than 100 µsec for the control duration per iRB, the proposal makes it completely satisfy an FA system demand on both fast and safety requirements.978-1-4799-7800-7/15/$31.00 ©2015 IEEE