NUM-Based Rate Allocation for Streaming Traffic via Sequential Convex Programming

In recent years, there has been an increasing demand for ubiquitous streaming like applications in data networks. In this paper, we concentrate on NUM-based rate allocation for streaming applications with the so-called S-curve utility functions. Due to non-concavity of such utility functions, the underlying NUM problem would be non-convex for which dual methods might become quite useless. To tackle the non-convex problem, using elementary techniques we make the utility of the network concave, however this results in reverse-convex constraints which make the problem non-convex. To deal with such a transformed NUM, we leverage Sequential Convex Programming (SCP) approach to approximate the non-convex problem by a series of convex ones. Based on this approach, we propose a distributed rate allocation algorithm and demonstrate that under mild conditions, it converges to a locally optimal solution of the original NUM. Numerical results validate the effectiveness, in terms of tractable convergence of the proposed rate allocation algorithm.Comment: 6 pages, conference submissio

WebPro: A proxy-based approach for low latency web browsing on mobile devices

Abstract—To load a webpage, a web browser first downloads the base HTML file of the page in order to discover the list of objects referenced in the page. This process takes roughly one round-trip time and constitutes a significant portion of the web browsing delay on mobile devices as wireless networks suffer from longer transmission and access delays compared to wired networks. In this work, we propose a solution for eliminating this initial delay, which is transparent to end systems, does not require modifying HTTP, and is well suited for web browsing on mobile devices. Our solution, called WebPro, relies on a network proxy that builds an up-to-date database of resource lists for the websites visited frequently by network users. The proxy resides in the wired part of the network, and hence can afford to pro-actively build and refresh the resource list database periodically. When a request for a webpage comes to the proxy, it simultaneously fetches the base HTML and all referenced objects required to render the webpage using the corresponding resource list stored in the local database. We have built a working prototype of WebPro and have conducted live experiments over WiFi and LTE networks. Our results show an average of 26% reduction in page load time for a mix of popular web sites chosen from categories such as news, sports and shopping. Moreover, in comparison to another best known proxy-based solution, WebPro provides delay reductions ranging from 5 % to 51 % for a variety of web sites. Keywords—Web browsing, Mobile devices, Browsing delay

Wound healing Benefits of Curcumin for Perineal Repair after Episiotomy: Results of an Iranian Randomized Controlled Trial

Pain and discomfort related to episiotomy have been reported to interfere with women's daily activities postpartum, such as sitting, walking and lifting the baby. To compare the effects of curcumin and Povidone-iodine solutions for episiotomy healing in primiparous women. 120 healthy primiparous women with a vaginal delivery at term were evaluated in this double-blind randomized clinical trial. Randomization was done using a table of random list numbers. Perineal healing was evaluated by research midwives blinded to random allocation at 24-48 hours and 10 days postpartum. Pain was assessed via a visual analogue scale and wound healing via the REEDA scale. Analysis was done on the intention-to-treat principle. The main outcome measure was the changes in wound healing between the two groups as measured by the REEDA Scale. Secondary outcome measures were perineal pain and wound healing 24-48 hours and 10 days after delivery. There was a greater decrease in the total scores of the REEDA in the curcumin group than in the Povidone-iodine (P < 0.001), however; there weren't significant differences between the groups on the VAS scores. The application of curcumin may assist in the episiotomy healing process and could be suitable replacement for Povidone-iodine. Esmaeili Vardanjani SA, Sehati Shafai F, Mohebi P, Deyhimi M, Delazar A, Ghojazadeh M, Malekpour M. Wound healing Benefits of Curcumin for Perineal Repair after Episiotomy: Results of an Iranian Randomized Controlled Trial. Life Sci J 2012;9(4):5536-5541] (ISSN:1097-8135). http://www.lifesciencesite.com. 82

Reducing Energy Consumption and Latency of Applications on Wireless Devices

Energy consumption and delay are the key factors influencing users' quality of experience for applications running on wireless devices. In cellular networks, providing a satisfactory user experience faces several challenges caused by the poor interactions between multiple factors. First, cellular networks suffer from long round trip times and also employ a radio resource control protocol, which keeps the radio of the device in high power state even after completion of a data transfer. Second, in most applications, completing a user action involves many round trips over the high-latency cellular link, which can lead to poor application performance. Moreover, periodic and intermittent traffic pattern exhibited by the majority of applications can result in serious energy inefficiencies. In this thesis, we address these challenges from the network and end device perspectives. First, we design a network-centric solution, called WebPro, that adopts speculative loading and bundling techniques to reduce latency and energy consumption of mobile web browsing. Performance evaluation results obtained through live experiments indicate that WebPro outperforms state-of-the-art, though the degree of improvement varies for different webpages. Then, we focus on energy-delay tradeoff on end devices and design algorithms to balance the energy-delay tradeoff inherent in bundling. Specifically, we formulate a generalized notion of bundling as an online optimization problem. The objective of this problem is to minimize the bundling cost defined as a weighted summation of energy and delay costs. Based on two different energy cost models associated with smartphones and internet of things (IoT) devices, we develop online algorithms to solve the optimization problem. A distinctive feature of our online algorithms is that they do not rely on any assumption about the traffic pattern or nature of applications. We provide theoretical performance bounds for our proposed algorithms by comparing them to an optimal offline algorithm. We evaluate the performance of our algorithms in a range of realistic scenarios using both model-driven simulations and real experiments on a smartphone. Our results show that depending on the delay tolerance level of a user, energy savings ranging from zero to about 100% can be achieved using our algorithms

Imaging chemical exchange saturation transfer (CEST) effects following tumor-selective acidification using lonidamine.

Increased lactate production through glycolysis in aerobic conditions is a hallmark of cancer. Some anticancer drugs have been designed to exploit elevated glycolysis in cancer cells. For example, lonidamine (LND) inhibits lactate transport, leading to intracellular acidification in cancer cells. Chemical exchange saturation transfer (CEST) is a novel MRI contrast mechanism that is dependent on intracellular pH. Amine and amide concentration-independent detection (AACID) and apparent amide proton transfer (APT*) represent two recently developed CEST contrast parameters that are sensitive to pH. The goal of this study was to compare the sensitivity of AACID and APT* for the detection of tumor-selective acidification after LND injection. Using a 9.4-T MRI scanner, CEST data were acquired in mice approximately 14 days after the implantation of 10(5) U87 human glioblastoma multiforme (GBM) cells in the brain, before and after the administration of LND (dose, 50 or 100 mg/kg). Significant dose-dependent LND-induced changes in the measured CEST parameters were detected in brain regions spatially correlated with implanted tumors. Importantly, no changes were observed in T1 - and T2 -weighted images acquired before and after LND treatment. The AACID and APT* contrast measured before and after LND injection exhibited similar pH sensitivity. Interestingly, LND-induced contrast maps showed increased heterogeneity compared with pre-injection CEST maps. These results demonstrate that CEST contrast changes after the administration of LND could help to localize brain cancer and monitor tumor response to chemotherapy within 1 h of treatment. The LND CEST experiment uses an anticancer drug to induce a metabolic change detectable by endogenous MRI contrast, and therefore represents a unique cancer detection paradigm which differs from other current molecular imaging techniques that require the injection of an imaging contrast agent or tracer. Copyright © 2015 John Wiley & Sons, Ltd