2011 German Escherichia coli outbreak: Alignment-free whole-genome phylogeny by feature frequency profiles

Accuracy of SNP-based whole-genome phylogeny reconstruction relies heavily on quality of sequence alignment which is particularly hindered by poorly assembled genomes. Alignment-free methods might provide additional insights. Here, we constructed a whole-genome phylogeny of 9 E.coli isolates from the 2011 German outbreak against existing E. coli genomes using the alignment-free feature frequency profile method. In addition, we looked for gene elements that distinguish the outbreak group from the other E. coli strains and possibly accounted for the emergence of the outbreak isolates using the distinguishing feature analysis

Coatings and methods for corrosion detection and/or reduction

Coatings and methods are provided. An embodiment of the coating includes microcapsules that contain at least one of a corrosion inhibitor, a film-forming compound, and an indicator. The microcapsules are dispersed in a coating vehicle. A shell of each microcapsule breaks down in the presence of an alkaline condition, resulting from corrosion

PH and Electrochemical Responsive Materials for Corrosion Smart Coating Applications

Corrosion is a costly issue for military operations and civil industries. While most corrosion initiates from localized corrosion form, such as pitting, failure directly caused by localized corrosion is the most dangerous kind, because it is difficult to anticipate and prevent, occurs very suddenly and can be catastrophic. One way of preventing these failures is with a coating that can detect and heal localized corrosion. pH and other electrochemical changes are often associated with localized corrosion, so it is expected that materials that are pH or otherwise electrochemical responsive can be used to detect and control corrosion. This paper will review various pH and electrochemical responsive materials and their potential applications in corrosion smart coatings. Current research results in this field will also be reported

Design of Ultra-compact Graphene-based Superscatterers

The energy-momentum dispersion relation is a fundamental property of plasmonic systems. In this paper, we show that the method of dispersion engineering can be used for the design of ultra-compact graphene-based superscatterers. Based on the Bohr model, the dispersion relation of the equivalent planar waveguide is engineered to enhance the scattering cross section of a dielectric cylinder. Bohr conditions with different orders are fulfilled in multiple dispersion curves at the same resonant frequency. Thus the resonance peaks from the first and second order scattering terms are overlapped in the deepsubwavelength scale by delicately tuning the gap thickness between two graphene layers. Using this ultra-compact graphene-based superscatterer, the scattering cross section of the dielectric cylinder can be enhanced by five orders of magnitude.Comment: This paper has been accepted by IEEE Journal of Selected topics in Quantum Electronic

The performance of a heat pump using nanofluid (R22+TiO2) as the working fluid – an experimental study

It has been well known that the nano-particles, including metals, oxides, carbides, or carbon nanotubes, can increase the conduction and convection coefficients and consequently, enhance the heat transfer. Using nanofluids as working fluids in the refrigeration, air-conditioning and heat pump systems has attracted much attention. This work set-up a test rig to experimentally study the system performance of a heat pump with nanofluid as refrigerant, which was prepared by mixing 5wt% TiO2 with R22. Results show that adding the nano particle TiO2 didn’t changed the heat absorbed in the evaporator clearly but increase the heat released in the condenser. As a results, compared to using pure R22, when using R22 + TiO2, the COP of the cooling cycle was decreased slightly, however, the COP of the heating cycle was increased significantly increased power consumption of compression.publishedVersio

Leakage discharge separation in multi-leaks pipe networks based on improved Independent Component Analysis with Reference (ICA-R) algorithm

The existing leakage assessment methods are not accurate and timely, making it difficult to meet the needs of water companies. In this paper, a methodology based on Independent Component Analysis with Reference (ICA-R) algorithm was proposed to give an more accurate estimation of leakage discharge in multi-leaks water distribution network without considering the specific individuality of one single leak. The proposed algorithm has been improved is improved to prevent error convergence in multi-leak pipe networks. Then an example EPANET model and a physical experimental platform were built to simulate and evaluate the flow in multi-leak WDNs, and the leakage flow rate is calculated by improved ICA-R algorithm and FastICA algorithm. The simulation results are shown the improved ICA-R algorithm has better performanc

Comparison of the Phenolic Content and Antioxidant Activities of Apocynum venetum L. (Luo-Bu-Ma) and Two of Its Alternative Species

The leaves of Apocynum venetum L. (AV), a native Chinese plant, have been used as folk medicine in China and Japan. This study evaluated the content of the active antioxidant component and antioxidant activities of AV, and its two alternative species, Poacynum pictum (Schrenk) Baill. (PP) and Poacynum hendersonii (Hook.f.) Woodson (PH). The total phenolic and total flavonoid contents were determined. In addition, the quantitative analysis of two major flavonoid compounds (hyperoside and isoquercitrin) was carried out by HPLC. The antioxidant activities were investigated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity method, the reducing power test and the chelating ability of ferrous ions. The highest total phenolic and flavonoid contents were observed in the AV methanolic extract, followed by the PP and PH methanolic extracts. HPLC analysis indicated that isoquercitrin was one of the major components in all three species, however, hyperoside was only detected in AV at high levels. All the antioxidant assays we performed demonstrated that the AV extract was markedly superior to those of the other two species

Synthesis of Elongated Microcapsules

One of the factors that influence the effectiveness of self-healing in functional materials is the amount of liquid healing agents that can be delivered to the damaged area. The use of hollow tubes or fibers and the more sophisticated micro-vascular networks has been proposed as a way to increase the amount of healing agents that can be released when damage is inflicted. Although these systems might be effective in some specific applications, they are not practical for coatings applications. One possible practical way to increase the healing efficiency is to use microcapsules with high-aspect-ratios, or elongated microcapsules. It is understood that elongated microcapsules will be more efficient because they can release more healing agent than a spherical microcapsule when a crack is initiated in the coating. Although the potential advantage of using elongated microcapsules for self healing applications is clear, it is very difficult to make elongated microcapsules from an emulsion system because spherical microcapsules are normally formed due to the interfacial tension between the dispersed phase and the continuous phase. This paper describes the two methods that have been developed by the authors to synthesize elongated microcapsules. The first method involves the use of an emulsion with intermediate stability and the second involves the application of mechanical shear conditions to the emulsion