Antibodies Regulate Dual-Function Enzyme IYD to Induce Functional Synergy between Metabolism and Thermogenesis

Iodotyrosine deiodinase (IYD) is a type of deiodinase enzyme that scavenges iodide from the thyroid gland. Previously, we showed that H3 Ab acts as an agonist on IYD to induce migration of cells to the heart and differentiate human stem cells into brown adipocyte-like cells. To continue this study, we investigated the dual function of IYD in hypothyroidism by blocking IYD and in thermogenesis by looking at the induction of brown adipocyte-like cells by treatment with H3 Ab in a mouse model. Surprisingly, our results suggest H3 Ab acts on IYD as both an antagonist and agonist to reduce T4 and increase core body temperature in the mouse model. Taken together, the data suggest IYD has a dual function that can regulate physiological metabolism and enhance thermogenesis.     

Dynamics of unentangled cyclic and linear poly(oxyethylene) melts

Monodisperse low-molecular-weight (400-1500 g/mol) cyclic poly(oxyethylene)s (CPOE)s were synthesized from linear dihydroxy-terminated poly(oxyethylene)s (LPOE)s. The self-diffusion, NMR spin-spin relaxation, and zero-shear viscosity of CPOE and LPOE, as well as linear dimethoxy-terminated poly(oxyethylene) (LPOEDE), were measured in the melt state. The self-diffusion coefficients measured at 56 °C were ordered in the following sequence: LPOEDE > CPOE > LPOE, which is in excellent agreement with NMR spin-spin relaxation and viscosity data. The slower motion of LPOE compared to LPOEDE was attributed to chain-end hydrogen bonding. Scaling relations with molecular weight and activation energies were reconciled with chain-end and topological effects.     

MCCA: a high-throughput MAC strategy for next-generation WLANs [medium access control protocols for wireless LANs]

Wireless LAN technology has been shown to he a revolutionary development during the last decade. Recently popularized IEEE 802.11a/g-based products can support up to 54 Mb/s physical layer rate and provide wireless access to the Internet. However, in order to deal robustly with the unreliable wireless nature, the 802.11 medium access control protocol has a relatively large overhead and hence, the throughput performance is much worse than the underlying physical layer rate. Moreover, along with many emerging applications and services over WLANs, such as voice over WLAN and audio/video streaming, the demand lor faster and higher- capacity WLANs has been growing recently. In this article, we propose a new medium access control protocol for the next-generation high-speed WLANs. The proposed medium access control, called multi-user polling controlled channel access, is composed of two components: multi-layer frame aggregation, which performs aggregation at both the medium access control and the physical layers; and multi-user polling, used to reduce the contention overhead and in turn, achieve higher network utilization. Multi-user polling controlled channel access is compared with the 802.11e-enhanced distributed channel access medium access control. Highly enhanced medium access control efficiency can be achieved by applying multi-user polling controlled channel access. We show the improved medium access control performance in terms of the aggregate throughput of non-QoS Hows with relevant QoS requirements.     

Measurement and analysis of online gaming services on mobile WiMAX networks

Online games have been played mainly in desktop computers over wired networks because of high speed and intensive computation requirements. The advances in mobile devices and ever increasing wireless link bandwidth motivate us to study whether players can enjoy online gaming over broadband wireless networks such as mobile Worldwide Inter‐operability for Microwave Access (WiMAX). In this paper, we carry out comprehensive measurements of the World of Warcraft (WoW) over the mobile WiMAX in Seoul, Korea, and analyze the network performance focusing on two aspects: (1) network layer dynamics such as round trip time, jitter, and packet loss and (2) WiMAX link layer statistics such as the radio signal strength, handovers, and piggyback mechanism. From the empirical data, we set up performance models and evaluate the performance of WoW over WiMAX. We also discuss how to improve the service quality of online gaming over WiMAX.Copyright © 2013 John Wiley & Sons, Ltd.