Fuzzy Logic Control of Adaptive ARQ for Video Distribution over a Bluetooth Wireless Link

Bluetooth's default automatic repeat request (ARQ) scheme is not suited to video distribution resulting in missed display and decoded deadlines. Adaptive ARQ with active discard of expired packets from the send buffer is an alternative approach. However, even with the addition of cross-layer adaptation to picture-type packet importance, ARQ is not ideal in conditions of a deteriorating RF channel. The paper presents fuzzy logic control of ARQ, based on send buffer fullness and the head-of-line packet's deadline. The advantage of the fuzzy logic approach, which also scales its output according to picture type importance, is that the impact of delay can be directly introduced to the model, causing retransmissions to be reduced compared to all other schemes. The scheme considers both the delay constraints of the video stream and at the same time avoids send buffer overflow. Tests explore a variety of Bluetooth send buffer sizes and channel conditions. For adverse channel conditions and buffer size, the tests show an improvement of at least 4 dB in video quality compared to nonfuzzy schemes. The scheme can be applied to any codec with I-, P-, and (possibly) B-slices by inspection of packet headers without the need for encoder intervention.</jats:p

Power-Constrained Fuzzy Logic Control of Video Streaming over a Wireless Interconnect

Wireless communication of video, with Bluetooth as an example, represents a compromise between channel conditions, display and decode deadlines, and energy constraints. This paper proposes fuzzy logic control (FLC) of automatic repeat request (ARQ) as a way of reconciling these factors, with a 40% saving in power in the worst channel conditions from economizing on transmissions when channel errors occur. Whatever the channel conditions are, FLC is shown to outperform the default Bluetooth scheme and an alternative Bluetooth-adaptive ARQ scheme in terms of reduced packet loss and delay, as well as improved video quality

Decreased expression of fecal miR-4478 and miR-1295b-3p in early-stage colorectal cancer

BACKGROUND: Colorectal cancer (CRC) is a major cause of cancer-related deaths world-wide. Detection of molecular markers in stool samples is a promising strategy for CRC screening. MicroRNAs (miRNAs) are short, non-coding RNA molecules that are commonly dysregulated in neoplasia. OBJECTIVE: The objective of this study was to evaluate the fecal miRNAs differentiation between early-stage CRC patients and healthy subjects. METHODS: Stool samples were collected from 40 patients with early stage (I, II) CRC and 16 healthy controls. RNA was extracted from all samples using miRNAeasy Mini Kits. MiRNA microarray expression profiling was performed with Agilent's miRNA Microarray system on 12 CRC and 8 normal stool samples. The expression levels of miR-4478 and miR-1295b-3p were determined by the SYBR Green miScript PCR system. RESULTS: In profiling study, we found 215 down-regulated miRNAs in CRC group. Furthermore, in validation study we found that the expression levels of fecal miR-4487 and miR-1295b-3p were significantly decreased in CRC patients compared to healthy controls. CONCLUSIONS: The expression of miR-4478 and miR-1295b-3p were significantly diminished in stool samples of CRC patients with early stage (I, II) in comparison with normal group. These miRNAs maybe use as potential non-invasive molecular markers for CRC diagnosis, but further studies are needed. © 2015 - IOS Press and the authors. All rights reserved

Downregulation of plasma MiR-142-3p and MiR-26a-5p in patients with colorectal carcinoma

Background: Colorectal cancer is one of the most commonly diagnosed cancers and cancer- related death worldwide. Identification of new specific biomarkers could be helpful to detection of this malignancy. Altered plasma microRNA expression has been identified in many cancers, including colorectal cancer. Objectives: The main objective of this study was to identify the circulating microRNAs with the most expression changes in colorectal cancer patients compared with neoplasm free healthy individuals. Materials and Methods: MicroRNA expression profiling was performed on plasma samples of 37 colorectal cancer patients and 8 normal subjects using microRNA microarray. Quantitative real-time reverse transcription polymerase chain reaction was used to validate the two selected altered microR NAs. Plasma samples from 61 colorectal cancer patients and 24 normal subjects were used in our validation study. Results: In profiling study we found a panel of six plasma microRNAs with significant downregulation. MicroRNA-142-3p and microRNA-26a-5p were selected and validated by polymerase chain reaction. Our results demonstrated that expression levels of plasma microRNA-142-3p and microRNA-26a-5p were significantly downregulated in patients with colorectal cancer when compared to control group. Conclusions: Our findings suggest that downregulation of plasma microRNA-142-3p and microRNA-26a-5p might serve as novel noninvasive biomarkers in the diagnosis of colorectal cancer, although more studies are needed to highlight the theoretical strengths. © 2015, Iranian Journal of Cancer Prevention

Emergence of hexatic and long-range herringbone order in two-dimensional smectic liquid crystals : A Monte Carlo study

Using a high resolution Monte Carlo simulation technique based on multi-histogram method and cluster-algorithm, we have investigated critical properties of a coupled XY model, consists of a six-fold symmetric hexatic and a three-fold symmetric herringbone field, in two dimensions. The simulation results demonstrate a series of novel continues transitions, in which both long-range hexatic and herringbone orderings are established simultaneously. It is found that the specific-heat anomaly exponents for some regions in coupling constants space are in excellent agreement with the experimentally measured exponents extracted from heat-capacity data near the smecticA-hexaticB transition of two-layer free standing film

Methodology for artificial microswimming using magnetic actuation

We propose a methodology for swimming at low-Reynolds-number flows based on ciliary motion of a microswimmer using magnetic actuation of artificial cilia.By solving the coupled magnetic-elastic-hydrodynamic problem, we demonstrate nonreciprocal effective and recovery strokes for cilia that nicely mimic natural cilia beating. Cilia drag forces, microswimmer net displacement, velocity, and efficiency are calculated, and we show the model can swim using a prespecified magnetic actuation. The proposed methodology can be used for devising biomedical microdevices that swim in viscous flows inside the human body

Mitigation of cascade failures in complex networks: theory and application

Complex networks such as transportation networks, the Internet, and electrical power grids are fundamental parts of modern life, and their robustness under any attack or fault has always been a concern. Failure and intentional removal of components in complex networks might affect the flow of information and change balance of flows in the network. This phenomenon may require load redistribution all over the network. Component overloaded can act as a trigger for a chain of overload failures. This overload, could, for example, increase the amount of information a router must transmit and ultimately make internet congestion. One of the major applications of complex network theory is to study power systems. Power systems are the most complex human-made infrastructures, and almost every individual&#039;s life is dependent on electrical energy and resilient functioning of power systems. Recently, there have been many reports about massive power outages leaving vast areas without power that sometimes takes a few days to have the power back. One of the most critical areas in the power system is the root cause analysis of such catastrophes and trying to resolve them. From an electrical engineering point of view, these power outages occur following an initial failure due to problems, such as generators tripping, transformers overheating, faulty power generation units, damage to the transmission system, substations or distribution systems, or overloading of the power system. A faulty protection relay or malicious attack to control centres can also trigger it. In any of these cases, the failed component will be out of service immediately and to keep the robust power delivery to all customers, their loads should be redistributed across the power system, and henceforth some of them might become overloaded as well, and accordingly get out of service. This chain of failures can be propagated all over the system and lead to a catastrophic blackout. This thesis conducts a full study on how to mitigate cascade failures in complex networks. First, cascade depth is applied to quantify nodes criticality for cascade failures. Then, a wide range of node centrality parameters is considered to find out the relationship between the node vitality and these centralities. To discover the structure of cascade propagation in complex networks, the edge geodesic distance is considered for computing the structural distance between two arbitrary edges in the network. Then, starting with the single edge removal events, the route that cascade tends to spread is studied. In the next step, the impact of two or three concurrent edge removals on the way the cascade spreads are examined. Besides, the power system vulnerability is studied using the maximum flow algorithm based on Ford-Fulkerson method and critical capacity parameters are identified. A synthetic model with the same properties as a real power system is generated and examined. For a power line, to be overloaded, a new method is developed to overpass across the network and shortlist the busbars for load reduction. Next, a novel sensitivity method is formulated based on AC load flow analysis to rank the loads according to their effect on the lines power flow