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With the advent of a consumer device such as a personal video recorder, recent advances in multimedia technologies have led to various enhanced services in the network area. In particular, a fiber channel arbitration loop-based network among PVRs has been presented to demonstrate the feasibility of high-quality content sharing. In addition, a multiple-loop architecture with shared disks, instead of expensive FC switches, has been devised in order to overcome the limit on the number of accommodable PVR users. Nevertheless, there arises the need for a practically constructible topology solution since the multiple-loop architecture is based on complete graph topology that requires the most connectivity for configuration. Therefore, we propose an innovative minimum spanning tree-based graph topology for multiple-loop topology organization. The MSG-based multiple-loop architecture can determine the constant average loop size and constant reject ratio, regardless of the number of deployed loops, and the acceptable total traffic with much less connectivity than CG, thereby effectively supporting high-quality live content sharing and distribution between PVRs. [ABSTRACT FROM AUTHOR]

The next generation broadband access networks must provide high speed bidirectional data channels and support more concurrent subscribers than ever before. While mega-bits-per-second data rates have been demonstrated for the downlink channels, progress on uplink has been slow. We propose a hybrid architecture for CDMA uplink that seamlessly integrates short-range radio and WCDMA interfaces in the same network. In our scheme, mobile stations (subscribers) can operate as Relaying Mobile Terminal (RMT) to relay uplink traffic for nearby mobile stations. Our analysis and simulations show that the deployment of RMTs significantly reduces the radio transmissions in the CDMA uplink. Moreover, the scheme results in a much lower out-of-cell interference to the neighboring network cells. The problem of finding the optimum RMT set turns out to be NP-hard. Several heuristics are evaluated in terms of RMT size and out-of-cell interference. In particular, we investigated a novel vertex cover based heuristic algorithm. Our method uses mobile pilot signals and mobile location to estimate a interference function for each node. This function is then used in selecting a maximum matching for the candidate RMT set. Simulation results are somewhat surprising: the simple greedy algorithm has very close performance to that of the optimum algorithm when only the RMT size is concerned. When out-of-cell interference is considered, the proposed algorithm outperforms both greedy and 2-approximation algorithm. [ABSTRACT FROM AUTHOR]

Community networks can provide the geographical advantage to cover and connect community members. In addition, it is more beneficial to share HD-quality content among those community members via the community networks. Recently, we have proposed a Personal video recorder (PVR) -based community network based on the multiple-loop Fiber Channel Arbitration Loop (FC-AL) connection, which can provide the scalability without using expensive FC-AL switches. As a community network size grows, however, popular programs tend to be stored redundantly in many PVRs, thereby wasting the storage space that could otherwise be used to store additional TV programs. Thus, we propose how to extend program storage hours in a community network by presenting storage saving algorithms for both PVRs and network disks. Through extensive simulations, we finally show that our schemes significantly extend program storage hours by an average of 69.7%. [ABSTRACT FROM AUTHOR]

With the advent of personal video recorders (PVRs), the way people watch TV is rapidly changing. By recording or time-shifting live TV programs into the embedded disk storage of a PVR, people can watch what they want independent of the broadcasting schedule. Furthermore, peer-to-peer networking technology provides an additional TV content distribution channel to unidirectional broadcasting. However, due to the current limited broadband bandwidth, it is difficult to support high-quality TV content streaming between PVRs on the Internet. In this article we propose a novel integrated network/storage architecture to provide the streaming of high-quality broadcast TV contents over fast network connections. To take full advantage of our system resources, we also develop efficient sharing schemes such as matching of a communication pair and channel assignment for extensive time-shifting. [ABSTRACT FROM AUTHOR]

The undergoing third-generation wireless network needs to support the integration of voice and multimedia data services with varying quality-of-service (QoS) requirements. It is critical that the least bit-error rate (BER) for voice traffic, World Wide Web (WWW) traffic, and streaming video traffic be guaranteed at all time. In this paper, we discussed the integration of soft handoff and dynamic spreading factor in wideband code-division multiple-access system in supporting multimedia traffic. The contribution of our work is twofold. First, the processing time of the handoff request is analyzed. We found that intensive mobile handoff might consume significant amount of access channel time and increase the delay of handoff. We, therefore, proposed a batch mechanism such that multiple handoff requests could be processed simultaneously. The average delay is reduced from 1.12 s to 800 ms at heavy handoff rate. Our second contribution is a new resource allocation algorithm, where the spreading factor and transmission power for the handoff mobiles are jointly considered to maximize the throughput. The BER requirements for the handoff mobiles and the target cell are maintained during the handoff process. The original problem is formulated into a nonlinear programming format. We proposed a procedure to simplify it into a linear constraint problem, which is solved by a revised simplex method. Numerical results show a 25% increase in throughput for WWW traffic and a 26% improvement for the video traffic. [ABSTRACT FROM AUTHOR]

Background: Emerging evidence suggests an important role of the human gut microbiome in psychiatry and neurodevelopmental disorders. An increasing body of literature based on animal studies has reported that the gut microbiome influences brain development and behavior by interacting with the gut-brain axis. Furthermore, as the gut microbiome has an important role in metabolism and is known to interact with pharmaceuticals, recent evidence suggests a role for the microbiome in antipsychotic-induced metabolic side effects in animals and humans., Purpose: Here we present the protocol for a two-phase study investigating the gut microbiome in healthy controls and in patients with schizophrenia treated with antipsychotics., Methods: Phase I of our study involves humans exclusively. We recruit 25 patients who are chronically treated with clozapine and compare them with 25 healthy controls matched for age, sex, BMI, and smoking status. A second cohort consists of 25 patients newly starting on clozapine, and a third cohort includes 25 antipsychotic-naive patients. The patients in the second cohort and third cohort are prospectively assessed for up to 6 and 12 weeks, respectively. Phase II of this study will incorporate microbiota humanized mouse models to examine the influence of human fecal transplant on metabolic parameters and the gut-brain axis. Progress and Future Directions: We are underway with the first participants enrolled in all phase I treatment cohorts. This study will contribute to elucidating the role of the gut microbiome in schizophrenia and metabolic side effects. In addition, its results may help to explore potential therapeutic targets for antipsychotic-induced metabolic side effects., (© 2019 S. Karger AG, Basel.)