Anchor View Allocation for Collaborative Free Viewpoint Video Streaming

In free viewpoint video, a viewer can choose at will any camera angle or the so-called "virtual view" to observe a dynamic 3-D scene, enhancing his/her depth perception. The virtual view is synthesized using texture and depth videos of two anchor camera views via depth-image-based rendering (DIBR). We consider, for the first time, collaborative live streaming of a free viewpoint video, where a group of users may interactively pull and cooperatively share streams of different anchor views. There is a cost to access the anchor views from the live source, a cost to "reconfigure" the peer network due to a change in selected anchors during view switching, and a distortion cost due to the distance of the virtual views to the received anchor views at users. We optimize the anchor views allocated to users so as to minimize the overall streaming cost given by the access cost, reconfiguration cost, and view distortion cost. We first show that, if the reconfiguration cost due to view switching is negligible, the view allocation problem can be optimally and efficiently solved in polynomial time using dynamic programming. For the case of non-negligible reconfiguration cost, the problem becomes NP-hard. We thus present a locally optimal and centralized algorithm inspired by Lloyd's algorithm used in non-uniform scalar quantization. We further propose a distributed algorithm with convergence guarantee, where each peer group independently makes merge-and-split decisions with a well-defined fairness criteria. Simulation results show that our algorithms achieve low streaming cost due to its excellent anchor view allocation

Generation of a recombinant rabies Flury LEP virus carrying an additional G gene creates an improved seed virus for inactivated vaccine production

The rabies Flury Low Egg Passage virus (LEP) has been widely used as a seed virus to generate inactive vaccine. Here, we established a reverse genetic system for LEP and generated a recombinant LEP virus (rLEP-G) that carries two identical G genes. This recombinant virus showed similar properties to those of LEP with respect to in vitro growth, neurotropism index, and virulence in mice. rLEP-G produced 4.3-fold more G protein than did LEP in BHK-21 cells. The inactivated vaccine generated from rLEP-G induced significantly higher virus neutralization titers in mice and dogs than those produced in response to LEP-derived vaccine. Our results suggest that rLEP-G is an improved seed virus candidate for inactivated rabies virus vaccine manufacture

Covalent Heterojunctions Enhance Bi2S3/Reduced Graphene Oxide (rGO) Nanocomposite Performance as Aqueous Zinc Ion Battery Material

The shortage of lithium resources, safety and recycling difficulty has focused attention on alternative energy storage devices in recent years. The aqueous zinc-ion battery (ZIB) stands out against such a background because of its earth abundance, safety, and environmental friendliness.1 However, the limited choice of cathode materials hinders the development of advanced high-energy-density aqueous ZIBs. At present, manganese oxide2 and vanadium oxide3 are the two most widely studied zinc-ion battery cathodes, but the migration of Zn2+ in these materials is limited by the strong electrostatic interaction with lattice oxygen ions, resulting in poor reversible capacity. Metal sulfides, instead, may effectively improve the electrochemical performance reversibility of ZIBs. Layered metal sulfides have been extensively studied in monovalent cation (Li+, Na+, K+) rechargeable batteries.4 However, although limited studies with Bi2S35,6 as ZIB cathode material exist, their detailed electrochemical charge storage and transfer mechanisms are not well understood. In this work, we explore the effect of covalent anchoring Bi2S3 on reduced graphene oxide (rGO) on the stability and cycling performance as a cathode for aqueous ZIBs. During the hydrothermal synthesis, the reduced graphene oxide serves as the nucleation substrate enabling the formation of fine and uniformly sized Bi2S3 grains, Figure 1 (a). Raman and X-ray photoelectron spectroscopy (XPS) confirm the formation of Bi-O-C heterojunctions during hydrothermal synthesis. These oxygen bridges serve as efficient electron transfer channels in the Bi2S3/rGO composite for rapid charge compensation during Zn2+ incorporation/extraction. As a result, Bi2S3/rGO composite shows notably better rate performance and cycling stability compared with pristine Bi2S3. The specific capacity of Bi2S3-rGO8 composite is ~186 mAh g-1 at the current density of 500 mA g-1 after 150 cycles, considerably higher than unsupported Bi2S3. Additionally, the Bi2S3 nucleated on GO with smaller particle sizes can shorten the transport path of zinc ions, which is beneficial for fast charge transfer. Therefore, Bi2S3-rGO8 can deliver more than 100 mAh g-1 at 10 A/g charge/discharge current density, Figure 1 (b). Also, the zinc storage mechanism was analyzed by X-ray diffraction spectroscopy (XRD) and XPS, indicating a reversible conversion reaction of Zn2+ in the Bi2S3-rGO framework. During discharging, Zn2+ is embedded in Bi2S3-rGO frame to form ZnS and Bi wrapped in rGO. The process is accompanied by the dissolution of bismuth into electrolyte and the formation of (ZnSO4)[Zn(OH)2]3·5H2O (ZHS) on the electrode surface. Inhibition of these two processes may further increase the cycle stability of Bi2S3-rGO. Rotating ring disc electrode (RRDE) measurements, in which we detect dissolved Bi, indicate that Bi dissolution in the electrolyte during charging/discharging is mitigated in Bi2S3/rGO electrode, compared to pristine Bi2S3

Seizure prediction : ready for a new era

Acknowledgements: The authors acknowledge colleagues in the international seizure prediction group for valuable discussions. L.K. acknowledges funding support from the National Health and Medical Research Council (APP1130468) and the James S. McDonnell Foundation (220020419) and acknowledges the contribution of Dean R. Freestone at the University of Melbourne, Australia, to the creation of Fig. 3.Peer reviewedPostprin

Effects of Structure and Constituent of Prussian Blue Analogs on Their Application in Oxygen Evolution Reaction

The importance of advanced energy-conversion devices such as water electrolysis has manifested dramatically over the past few decades because it is the current mainstay for the generation of green energy. Anodic oxygen evolution reaction (OER) in water splitting is one of the biggest obstacles because of its extremely high kinetic barrier. Conventional OER catalysts are mainly noble-metal oxides represented by IrO2 and RuO2, but these compounds tend to have poor sustainability. The attention on Prussian blue (PB) and its analogs (PBA) in the field of energy conversion systems was concentrated on their open-framework structure, as well as its varied composition comprised of Earth-abundant elements. The unique electronic structure of PBA enables its promising catalytic potential, and it can also be converted into many other talented compounds or structures as a precursor. This undoubtedly provides a new approach for the design of green OER catalysts. This article reviews the recent progress of the application of PBA and its derivatives in OER based on in-depth studies of characterization techniques. The structural design, synthetic strategy, and enhanced electrochemical properties are summarized to provide an outlook for its application in the field of OER. Moreover, due to the similarity of the reaction process of photo-driven electrolysis of water and the former one, the application of PBA in photoelectrolysis is also discussed

Effects of Structure and Constituent of Prussian Blue Analogs on Their Application in Oxygen Evolution Reaction

This article reviews the recent progress of the application of PBA and its derivatives in OER based on in-depth studies of characterization techniques. The structural design, synthetic strategy, and enhanced electrochemical properties are summarized to provide an outlook for its application in the field of OER. Moreover, due to the similarity of the reaction process of photo-driven electrolysis of water and the former one, the application of PBA in photoelectrolysis is also discussed