Distributed optimization framework for in-network data processing

In-Network Processing (INP) is an effective way to aggregate and process data from different sources and forward the aggregated data to other nodes for further processing until it reaches the end user. There is a trade-off between energy consumption for processing data and communication energy spent on transferring the data. Specifically, aggressive data aggregation consumes much energy for processing, but results in less data for transmission, thus using less energy for communications, and vice versa. An essential requirement in the INP process is to ensure that the user expectation of quality of information (QoI) is delivered during the process. Using wireless sensor networks for illustration and with the aim of minimising the total energy consumption of the system, we study and formulate the trade-off problem as a nonlinear optimisation problem where the goal is to determine the optimal data reduction rate, while satisfying the QoI required by the user. The formulated problem is a Signomial Programming (SP) problem, which is a non-convex optimisation problem and very hard to be solved directly. We propose two solution frameworks. First, we introduce an equivalent problem which is still SP and non-convex as the original one, but we prove that the strong duality property holds, and propose an efficient distributed algorithm to obtain the optimal data reduction rates, while delivering the required QoI. The second framework applies to the system with identical nodes and parameter settings. In such cases, we prove that the complexity of the problem can be reduced logarithmically. We evaluate our proposed frameworks under different parameter settings and illustrate the validity and performance of the proposed techniques through extensive simulation

Electric Power Grid Resilience to Cyber Adversaries: State of the Art

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. The smart electricity grids have been evolving to a more complex cyber-physical ecosystem of infrastructures with integrated communication networks, new carbon-free sources of powergeneratio n, advanced monitoring and control systems, and a myriad of emerging modern physical hardware technologies. With the unprecedented complexity and heterogeneity in dynamic smart grid networks comes additional vulnerability to emerging threats such as cyber attacks. Rapid development and deployment of advanced network monitoring and communication systems on one hand, and the growing interdependence of the electric power grids to a multitude of lifeline critical infrastructures on the other, calls for holistic defense strategies to safeguard the power grids against cyber adversaries. In order to improve the resilience of the power grid against adversarial attacks and cyber intrusions, advancements should be sought on detection techniques, protection plans, and mitigation practices in all electricity generation, transmission, and distribution sectors. This survey discusses such major directions and recent advancements from a lens of different detection techniques, equipment protection plans, and mitigation strategies to enhance the energy delivery infrastructure resilience and operational endurance against cyber attacks. This undertaking is essential since even modest improvements in resilience of the power grid against cyber threats could lead to sizeable monetary savings and an enriched overall social welfare

In vitro cytotoxic and anti-cancer effects of body wall for sea cucumber (Holothuria leucospilota)

In recent years efforts to find bioactive compounds from live organisms especially marine animals have been increased. In the present study, the anticancer and cytotoxic effects of sea cucumber body walls (Holothuria leucospilota) were investigated. For this purpose, sea cucumbers were collected from Larak Island at depths of 10 to 30 m and extraction process was done with methanol and diethyl ether solvent which then concentrated by rotary evaporator (40℃) following lyophilization with vacuum freeze dryer. XTT method was used to investigate anticancer and cytotoxic effects of body wall extracts. The results showed that the methanolic extract could prevent proliferation of human oral epidermoid carcinoma cells (KB) at concentrations of 100 and 500 μg/ml. The diethyl etheric extract also could prevent proliferation of KB at 500 μg/ml concentration. Overall result showed that sea cucumber body wall had a strong cytotoxic effect on normal cell line (Human embryonic kidney cell [HEK]) which can be used as potent cytotoxic material. However these extracts did not show significant therapeutic value against KB cells

Comparison of antibacterial activities of Ircinia mutans extracts in two different seasons from Kish Island, Persian Gulf, Iran

Sponges, which constitute the phylum Porifera, are the most primitive of the multicellular animals, among all marine organisms screened. Marine sponges produce the largest number of structurally diversified natural products. In this study we investigated in vitro antimicrobial activity of Ircinia mutans collected from the Kish Island in the Persian Gulf against strains of bacteria Escherichia coli (ATCC 15224), Pseudomonas aeruginosa (ATCC 25619), Staphylococcus aureus (ATCC 1764), and Bacillus subtilis spizizenii (ATCC 6633). Diethyl etter, methanol and aqueous extracts of sponge were evaluated by using the Bacterial Broth Dilution Method. The results showed that the aqueous extracts didn’t have any antibacterial activity. Minimum Inhibitory Concentrations (MIC) of the winter diethyl etter extract was 2 mg/ml for E.coli and 20 mg/ml for P. aeruginosa, whereas the summer diethyl etter extract and both of methanol extracts did not show any activity. The MIC and MBC (Minimum Bacterial Concentration) of summer diethyl etter extracts were 2 mg/ml and 3mg/ml against S. aureus; and 5mg/ml and 10mg/ml when tested on B. subtilis. The MIC and MBC of winter diethyl etter extracts were measured as 1.5 mg/ml and 2mg/ml against S. aurous; and 5mg/ml and 10mg/ml when examined on B. subtilis. Summer and winter methanol and aqueous extracts of I. mutans did not show any activity against these bacteria. Therefore secondary metabolite solutions in diethyl etter contain components with antibacterial properties and can be used as antibiotics products

Microbiological qualification of air, water and dialysate in a haemodialysis centre; a new focus on Legionella spp.

Background and Objectives: The microbiological monitoring of the water used for haemodialysis is important especially for Legionella and non-fermentative bacteria since patients with end stage renal disease (ESRD) are suffering from deteriorated function of immune system. Materials and Methods: A total 50 water and dialysate samples were weekly collected over a period of 10 weeks from 5 sites. Total and faecal coliforms were determined by utilizing the most probable number (MPN) method. For isolation of Legionella, water samples were inoculated on a BCYE medium. DNA extraction was performed and was used to amplify 16S rRNA gene of Legionella species. Airborne bacteria were sampled using a single stage Andersen air sampler. Results: Out of total 50 water samples, 24 samples had bacterial contamination. The highest rate of Legionella contamination was observed in the storage tank (67 cfu/ml). Legionella was not isolated from the dialysate effluent samples. The highest rate of total bacterial count was related to the dialysate effluent and the maximum total count of coliforms was related to the reverse osmosis. The isolated bacteria were Gram-negative bacilli (mostly Pseudomonas isolates), Gram-positive cocci (mostly Micrococcus spp.) and Gram-positive bacilli (mostly Bacillus spp.). Six samples were contaminated with coliforms. No faecal coliform was isolated from the samples. Conclusion: These results indicated that dialysis machine is an important source of contaminations such as Staphylococcus, Pseudomonas and Legionella. Therefore an efficient prevention program is needed to eliminate bacterial contamination of dialysis water system. Moreover, in haemodialysis centres, periodic surveillance programs for microbiological qualification can lead to a better planning for disinfection of haemodialysis water systems. © 2016, Tehran University of Medical Science. All rights reserved