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Saidi S.,Center de Biotechnologie de la Technopole de Borj-Cedria | Ramirez-Bahena M.-H.,CSIC - Institute of Natural Resources and Agriculture Biology of Salamanca | Ramirez-Bahena M.-H.,University of Salamanca | Santillana N.,San Cristobal of Huamanga National University | And 6 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2014

Several fast-growing strains nodulating Vicia faba in Peru, Spain and Tunisia formed a cluster related to Rhizobium leguminosarum. The 16S rRNA gene sequences were identical to that of R. leguminosarum USDA 2370T, whereas rpoB, recA and atpD gene sequences were phylogenetically distant, with sequence similarities of less than 96 %, 97 % and 94 %, respectively. DNA-DNA hybridization analysis showed a mean relatedness value of 43 % between strain FB206T and R. leguminosarum USDA 2370T. Phenotypic characteristics of the novel strains also differed from those of the closest related species of the genus Rhizobium. Therefore, based on genotypic and phenotypic data obtained in this study, we propose to classify this group of strains nodulating Vicia faba as a novel species of the genus Rhizobium named Rhizobium laguerreae sp. nov. The type strain is FB206T (= LMG 27434T = CECT 8280T). © 2014 IUMS. Source


Cortez N.E.,San Cristobal of Huamanga National University | Cortez N.E.,Sao Paulo State University | Ferreira R.P.,Sao Paulo State University | Baptista F.G.,Sao Paulo State University | Filho J.V.,Sao Paulo State University
Structural Health Monitoring 2013: A Roadmap to Intelligent Structures - Proceedings of the 9th International Workshop on Structural Health Monitoring, IWSHM 2013 | Year: 2013

This paper presents a novel wireless structural health monitoring (SHM) system based on a new method to detect damage in structures using the electromechanical impedance (EMI) principle. The proposed system is a wireless and low-power sensor network based on ZigBee composed by a link node to establish communication between remote monitoring center (host node and server) and multiple sensor nodes. The identification of damage is performed by simply comparing the variations of root main square (RMS) voltage from response signals of piezoelectric transducers. Source


Quille R.,San Marcos University of Costa Rica | Bustamante A.,San Marcos University of Costa Rica | Palomino Y.,San Cristobal of Huamanga National University
Hyperfine Interactions | Year: 2011

The ceramic industry is an important area of economic activity in the Ayacucho Region, in particular in the District of Quinua. As a consequence, there is a huge demand for clay to produce ceramic pastes in that region. This paper reports on results concerning the mineralogical characterization of four clayey samples, which were collected MAA and SPQA from the area Pampa de La Quinua with geographic coordinates 13° 02′ 49″ S 74° 08′ 03″ W, CE1M and CE2M from the Quinua locality 13° 03′ 07″ S 74° 08′ 31″ W, both in the District of Quinua, Province of Huamanga, Ayacucho, Peru. The chemical and mineralogical characterization of these samples was carried out with powder X-ray diffraction detecting quartz, albite, montmorillonite, kaolinite and glauconite mineral phases, Mössbauer spectroscopy detected iron in kaolinite, glauconite and montmorillonite minerals. Chemical analysis was performed through scanning electron microscopy and energy dispersive X-ray spectroscopy. Data obtained from the combination of these techniques provided relevant information about the morphology, chemical composition, and the mineralogy of samples. © 2011 Springer Science+Business Media B.V. Source


Cortez N.E.,San Cristobal of Huamanga National University | Cortez N.E.,Sao Paulo State University | Filho J.V.,Sao Paulo State University | Baptista F.G.,Sao Paulo State University
Journal of Intelligent Material Systems and Structures | Year: 2015

This article presents the design and implementation of a novel wireless structural health monitoring system based on the electromechanical impedance principle. The proposed system is a wireless low-power scalable sensor network composed of multiple sensor nodes and a link node used as master to establish communication with the remote monitoring center (host node and server). The link node communicates with the remote monitoring center through a Global System for Mobile Communications/General Packet Radio Services network and with other sensor nodes through a ZigBee network. Each sensor node is a portable and autonomous structural health monitoring core based on microcontroller, digital synthesizer, and transceiver ZigBee. The identification of damage is performed by simply comparing the variations in root mean square voltage obtained from piezoelectric transducers, such as lead zirconate titanate patches, bonded to the structure. The lead zirconate titanate patches are excited on a wideband frequency range, and it is not necessary to compute the electromechanical impedance. The proposed system was built and experiments were carried out on an aluminum structure, and excellent results have been obtained. Our contribution ranges from the hardware to the graphical front end. © The Author(s) 2014. Source


Cortez N.E.,San Cristobal of Huamanga National University | Filho J.V.,Sao Paulo State University | Baptista F.G.,Sao Paulo State University
Structural Health Monitoring | Year: 2013

This article presents a new method to detect damage in structures based on the electromechanical impedance principle. The system follows the variations in the output voltage of piezoelectric transducers and does not compute the impedance itself. The proposed system is portable, autonomous, versatile, and could efficiently replace commercial instruments in different structural health monitoring applications. The identification of damage is performed by simply comparing the variations of root mean square voltage from response signals of piezoelectric transducers, such as lead zirconate titanate patches bonded to the structure, obtained for different frequencies of the excitation signal. The proposed system is not limited by the sampling rate of analog-to-digital converters, dispenses Fourier transform algorithms, and does not require a computer for processing, operating autonomously. A low-cost prototype based on microcontroller and digital synthesizer was built, and experiments were carried out on an aluminum structure and excellent results have been obtained. © The Author(s) 2012. Source

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