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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]

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]

An emerging body of literature demonstrates differences in the gut microbiome (GMB) of patients with major depressive disorder (MDD) compared to healthy controls (HC), as well as the potential benefits of prebiotic, probiotic, and synbiotic treatment. We conducted a systematic review of 24 observational studies (n = 2817), and 19 interventional trials (n = 1119). We assessed alpha diversity, beta diversity, and taxa abundance changes in patients with MDD relative to HC, as well as the effect of prebiotics, probiotics, and synbiotics on depressive symptoms in individuals with clinical or subclinical depression. We observed no significant differences in alpha diversity but a significant difference in beta diversity between patients with MDD and HC. There were fluctuations in the abundance of specific taxa in patients with MDD relative to HC. Probiotic and synbiotic, but not prebiotic, treatment showed a modest benefit in reducing depressive symptoms in patients with MDD over four to nine weeks. The GMB profiles of patients with MDD differ significantly from HC, but further studies are needed to elucidate the benefits of prebiotic, probiotic and synbiotic treatments relative to antidepressants and over longer follow-up before these therapies are implemented into clinical practice. [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 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]