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Bevacizumab in neoadjuvant therapy provides a new hope of improved survival for patients with triple-negative breast cancer (TNBC) by targeting vascular endothelial growth factor in combination with chemotherapy, but curative effect is limited by bevacizumab’s continuous use while mechanisms remain incompletely understood. More and more researches reported that tumor-associated macrophages mediate resistance to chemotherapy and radiotherapy in various tumors. Here we developed a TNBC model resistant to bevacizumab under bevacizumab continuous administration. It was found that proportion of a specific subset of tumor-associated macrophages characterized as M2b (CD11b+ CD86high IL10high) increased and responsible for acquired resistance to bevacizumab. Then, we showed that RAW264.7 macrophages could be polarized to M2b subtype on simultaneous exposure to bevacizumab and TLR4 ligands as occurs in the context of continuous bevacizumab treatment. Concordantly, in TLR4-deleted C57BL/10ScNJNju (TLR4lps–del) mut/mut mice with bevacizumab treatment model, it was verified that the M2b macrophage could be induced by Fc gamma receptor-TLR4 cross-talk. In MDA-MB-231-resistant tumor-bearing mice, the content of TNFα in serum kept going up consistent with CCL1, a chemokine of M2b macrophage. In vitro neutralizing tumor necrosis factor α (TNFα) could inhibit the tumor progression caused by M2b culture medium and tumor IDO1 expression. Therefore, we thought that TNFα is a key tumor-promoting effector molecule secreted by M2b macrophage. Accordingly, the curative effect of bevacizumab was proved to be significantly improved by neutralizing TNFα with anti-TNFα nanobody. This study is expected to provide theoretical and clinical evidence elucidating the drug resistance in patients receiving bevacizumab.

Low-delay hierarchical coding structure (LD-HCS), as one of the most important components in the latest High Efficiency Video Coding (HEVC) standard, greatly improves coding performance. It groups consecutive P/B frames into different layers and encodes them with different quantization parameters (QPs) and reference mechanisms in such a way that temporal dependency among frames can be exploited. However, due to varying characteristics of video contents, temporal dependency among coding units differs significantly from each other in the same or different layers, while a fixed LD-HCS scheme cannot take full advantage of the dependency, leading to a substantial loss in coding performance. This paper addresses the temporally dependent rate distortion optimization (RDO) problem by attempting to exploit varying temporal dependency of different units. First, the temporal relationship of different frames under the LD-HCS is examined, and hierarchical temporal propagation chains are constructed to represent the temporal dependency among coding units in different frames. Then, a hierarchical temporally dependent RDO scheme is developed specifically for the LD-HCS based on a source distortion propagation model. Experimental results show that our proposed scheme can achieve 2.5% and 2.3% BD-rate gain in average compared with the HEVC codec under the same configuration of P and B frames, respectively, with a negligible increase in encoding time. Furthermore, coupled with QP adaption, our proposed method can achieve higher coding gains, e.g., with multi-QP optimization, about 5.4% and 5.0% BD-rate saving in average over the HEVC codec under the same setting of P and B frames, respectively.

The lotus-type porous copper with various pore structural parameters was fabricated by a novel solid-gas eutectic solidification process (the Gasar process). The effects of porosity and the Angle between load direction and pores axis (ALP) on compressive behaviours of porous copper were investigated. The results show that the compressive stress-strain curves vary with porosity and compressive direction. Under the same compressive direction, as the porosity increases, the compressive yield strength of the porous copper decreases. The compressive properties of the porous copper show obvious anisotropy, and the yield strength of the porous copper decreases with increasing the angle between pore axis and compressive direction. The Deformation mechanisms analyzed by finite element simulation (FES) are well consistent with experiment process for the samples with ALP of 0° and 90°.

This article addresses the problem of reference picture optimization in video communication over error prone networks. A novel estimation model for transmission distortion is proposed. This model is capable of recursively estimating the overall end-to-end distortion caused by quantization, error propagation, and error concealment. Simulation results show that this model can accurately estimate channel distortion. Then, based on the distortion estimation model, a new non-feedback key-frame reference picture selection (KRPS) algorithm is developed. The optimum reference picture minimizes the transmission distortion under the rate-distortion optimization framework. Extensive experiment results demonstrate that the proposed KRPS algorithm substantially achieves more peak signal to noise ratio (PSNR) gain over traditional prediction, especially in low bit-rate transmission.

Rate-distortion optimization (RDO) is widely employed to maximize coding efficiency in hybrid video coding. Due to an extensive use of spatial-temporal predictions in video coding, a global RDO problem becomes so complex that the processing of each coding unit (e.g. a macro block) is dependent and entangled each other. Usually the RDO is simply performed for each coding unit individually and independently, thus compromising the RDO performance significantly. In this paper, we examine temporal dependent RDO by developing a novel source distortion temporal propagation (SDTP) model, which takes into account the influence of a current coding macro block to future macro blocks in its temporal propagation chain. Accordingly estimations of the influence and the corresponding Lagrange multiplier for the proposed SDTP-based RDO are obtained. Experimental results show consistently a significant coding gain of the proposed scheme over H.264/AVC.

Most common video coding standards employ spatiotemporal prediction techniques to increase coding efficiency. As a result, compressed video data is sensitive to the transmission error due to error propagation. An adaptive reference picture selection (RPS) is proposed to improve the error resilience in real-time video transmission. A global rate-distortion optimization (RDO) is developed to intelligently select the reference picture from a reference picture list, such that the end-to-end distortion is minimized. The coupling variables in the global RDO are decoupled by applying primal decomposition approach iteratively. Experimental results in H.264/AVC indicate that the proposed adaptive RPS significantly outperforms the ACK and NACK mode of the classic RPS, and error resilient RDO in H.264/AVC reference software as well.

This paper presents design, control and implementation of the humanoid robot platform Robo-Erectus Senior (RESr-1). It is a full-size humanoid robot using self-contained modular component to perform cooperative works in general humanoid environment and robotic soccer (RoboCup) in particular. Mechatronic drives has cubic or double design with multiple connecting sockets in different orientations. Thereby, actuators, passive joints, rigid links can be rapidly assembled with various configurations having different kinematics and dynamic characteristics. In RESr-1, serial connected legs are parallel connected and controlled with individual controller. Based on the hierarchical control concept, low level trajectory are generated by decomposing locomotion into key poses as observed in humanoid locomotion. These poses are connected by sine, cosh and third-order interpolation functions. Thereby, walking pattern trajectories can satisfy continuity, smoothness with simple mathematical form. Simple locomotion planning methods for biped walking, turning and kicking are described. The proposed method provides a set of standard parameters for further optimization and learning with feedback information. It has been tested on RESr-1, which gave a outstanding exhibition in the Humanoid League of RoboCup2007. As shown in the experimental result, gaits are stable with various parameter value of stride length, pace time and double support phase ratio.

In order to overcome the disadvantages of lacking flexibility, robustness and scalability of the traditional remote video monitoring system (RVMS) for substations, we propose a model of distributed RVMS based on multi-agent techniques. In this model, complicated control of traditional monitoring system can be simplified and decentralized based on the features of independence and cooperativeness of agent work groups. The architecture and operation principle of the model is analyzed in detail and the design and implementation of universal agent modules are also presented. Furthermore, two algorithms based on the new H.264/AVC coding standard, namely, the controllable predictive fast search algorithm for block matching motion estimation and the motion vector recovery algorithm are adopted respectively in two important agent work groups, DCG and ECG. Simulation results show that real-time video transmission via error prone channels can be realized by cooperative communications of agent groups, the strategies of video compressing and communications can be dynamically changed according to correspond situation. Therefore, efficient video monitoring of substations can be achieved by using this model.

Error resilience to packet loss is a critical requirement in predictive video coding for transmission over packet-switched networks, since the prediction loop propagates error and causes substantial degradation in video quality. This paper proposes an algorithm based on the rate-distortion optimization model of H.263 to approximately estimate the quantization distortion of one frame. By analyzing the overall distortion of the decoder, an algorithm to estimate the rough propagation is presented. Based on these acquirements, a real time intra-update criterion is proposed, which reduces the computational complexity significantly. Through comparing the increased quantization distortion by intra-updating and reduced need to intra-update a macroblock, the encoder can quickly decide whether there is a need to intra-update a macroblock. Based on TMN8 coder, the performance of the proposed algorithm and the traditional R-D optimized intra-update method is compared. Simulation results demonstrate that proposed method achieves the same or even better gains in PSNR over traditional method.

In this paper, the error concealment techniques as motion vector extrapolation (MVE), boundary matching (BM), side matching (SM), 16/spl times/16-MB-based and 8/spl times/8-block-based concealment are implemented and compared with feedback-based no waiting ARQ (NWARQ) error recovery technique. A new error concealment method using preprocessing (PREP) and search is proposed and implemented. This new method tries to use the information of surrounding MV as much as possible, and find a more precise motion vector using additional search processing in a search window centered by the estimated motion vector. Simulation results, based JM1.4 codec of JVT, show that both NWARQ and PREP can significantly improve the reconstruction video quality. And the combined PREP, SEARCH and NWARQ techniques can greatly achieve improved performance. From the simulation results, the SM and 16/spl times/16-MB-based concealment methods show better performance than BM and 8/spl times/8-block-based concealment.

Motion search is a key technique to motion compensated video coding standards (Jo Yew Tham et al., 1998). A novel controllable predictive cross-diamond fast search algorithm is proposed based on intense study of motion vector characteristics. The proposed algorithm takes advantage of "stop when good enough" spirit in PMVFAST (A. M. Tourapis et al., 2000) and multiple initial predictor candidates (MIPC) concept in APDZS, and new controllable search criteria are set down. Simulation results demonstrate that the proposed algorithm is better than other recently proposed algorithms in term of PSNR performance and required number of search points, and moreover, the proposed algorithm can control the search speed according to practical demands.

When transmitted over error prone networks, the compressed video can suffer severe degradation. One approach to combat the error effect is the concealment technique. A novel temporal concealment method is proposed. The technique first extrapolates motion vectors of macroblock (MB) to the corrupted frame. Then, the overlapped areas between the damaged block and the motion extrapolation MBs are estimated, and the best estimation motion vector is obtained. Finally, the corrupted block is concealed with the block in the previous frame. This method overcomes the disadvantages of incorrect MB displacement, and decreases the computational complexity compared with the methods based on pixels. Simulation results, with one entire frame lost or interlace group of blocks (GOBs) lost and an H.263+ codec, show satisfactory concealment performance of the proposed technique and the suitability for real-time video packet applications.