7,863 research outputs found
Simulation of Electric Vehicles Combining Structural and Functional Approaches
In this paper the construction of a model that represents the behavior of an Electric Vehicle is described. Both the mechanical and the electric traction systems are represented using Multi-Bond Graph structural approach suited to model large scale physical systems. Then the model of the controllers, represented with a functional approach, is included giving rise to an integrated model which exploits the advantages of both approaches. Simulation and experimental results are aimed to illustrate the electromechanical interaction and to validate the proposal.Fil: Silva, Luis Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Grupo de Electronica Aplicada; ArgentinaFil: Magallán, Guillermo Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Grupo de Electronica Aplicada; ArgentinaFil: de la Barrera, Pablo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Grupo de Electronica Aplicada; ArgentinaFil: de Angelo, Cristian Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Grupo de Electronica Aplicada; ArgentinaFil: Garcia, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Grupo de Electronica Aplicada; Argentin
T35: a small automatic telescope for long-term observing campaigns
The T35 is a small telescope (14") equipped with a large format CCD camera
installed in the Sierra Nevada Observatory (SNO) in Southern Spain. This
telescope will be a useful tool for the detecting and studying pulsating stars,
particularly, in open clusters. In this paper, we describe the automation
process of the T35 and show also some images taken with the new
instrumentation.Comment: 13 pages, 9 figures. Accepted for publication in the special issue
"Robotic Astronomy" of Advances of Astronom
Unraveling beam self-healing
We show that, contrary to popular belief, non only diffraction-free beams may
reconstruct themselves after hitting an opaque obstacle but also, for example,
Gaussian beams. We unravel the mathematics and the physics underlying the
self-reconstruction mechanism and we provide for a novel definition for the
minimum reconstruction distance beyond geometric optics, which is in principle
applicable to any optical beam that admits an angular spectrum representation.
Moreover, we propose to quantify the self-reconstruction ability of a beam via
a newly established degree of self-healing. This is defined via a comparison
between the amplitudes, as opposite to intensities, of the original beam and
the obstructed one. Such comparison is experimentally accomplished by tailoring
an innovative experimental technique based upon Shack-Hartmann wave front
reconstruction. We believe that these results can open new avenues in this
field
2b-RAD genotyping for population genomic studies of Chagas disease vectors: Rhodnius ecuadoriensis in Ecuador
Background:
Rhodnius ecuadoriensis is the main triatomine vector of Chagas disease, American trypanosomiasis, in Southern Ecuador and Northern Peru. Genomic approaches and next generation sequencing technologies have become powerful tools for investigating population diversity and structure which is a key consideration for vector control. Here we assess the effectiveness of three different 2b restriction site-associated DNA (2b-RAD) genotyping strategies in R. ecuadoriensis to provide sufficient genomic resolution to tease apart microevolutionary processes and undertake some pilot population genomic analyses.
Methodology/Principal findings:
The 2b-RAD protocol was carried out in-house at a non-specialized laboratory using 20 R. ecuadoriensis adults collected from the central coast and southern Andean region of Ecuador, from June 2006 to July 2013. 2b-RAD sequencing data was performed on an Illumina MiSeq instrument and analyzed with the STACKS de novo pipeline for loci assembly and Single Nucleotide Polymorphism (SNP) discovery. Preliminary population genomic analyses (global AMOVA and Bayesian clustering) were implemented. Our results showed that the 2b-RAD genotyping protocol is effective for R. ecuadoriensis and likely for other triatomine species. However, only BcgI and CspCI restriction enzymes provided a number of markers suitable for population genomic analysis at the read depth we generated. Our preliminary genomic analyses detected a signal of genetic structuring across the study area.
Conclusions/Significance:
Our findings suggest that 2b-RAD genotyping is both a cost effective and methodologically simple approach for generating high resolution genomic data for Chagas disease vectors with the power to distinguish between different vector populations at epidemiologically relevant scales. As such, 2b-RAD represents a powerful tool in the hands of medical entomologists with limited access to specialized molecular biological equipment.
Author summary:
Understanding Chagas disease vector (triatomine) population dispersal is key for the design of control measures tailored for the epidemiological situation of a particular region. In Ecuador, Rhodnius ecuadoriensis is a cause of concern for Chagas disease transmission, since it is widely distributed from the central coast to southern Ecuador. Here, a genome-wide sequencing (2b-RAD) approach was performed in 20 specimens from four communities from Manabí (central coast) and Loja (southern) provinces of Ecuador, and the effectiveness of three type IIB restriction enzymes was assessed. The findings of this study show that this genotyping methodology is cost effective in R. ecuadoriensis and likely in other triatomine species. In addition, preliminary population genomic analysis results detected a signal of population structure among geographically distinct communities and genetic variability within communities. As such, 2b-RAD shows significant promise as a relatively low-tech solution for determination of vector population genomics, dynamics, and spread
Caracterización morfológica y molecular de nueve variedades botánicas de tigridia pavonia (l.f.) dc
Tigridia pavonia (L.f.) DC es una planta bulbosa nativa de México con potencial ornamental alto. México es considerado el centro de mayor diversidad de esta especie, por lo cual, el estudio de su diversidad genética y fenotípica es muy importante para establecer estrategias de manejo, conservación y utilización en programas de mejoramiento genético. El objetivo de este estudio fue caracterizar nueve variedades botánicas de Tigridia pavonia (L.f.) DC, con 21 marcadores morfológicos y cinco moleculares ISSR (ínter-Secuencias Simples Repetidas). Las variedades fueron recolectadas en tres municipios del Estado de México: Tenancingo (2100 m), Temascaltepec (2250 m) y Temoaya (2600 m). La distancia genética promedio para morfología fue 0.54, mientras que para ISSR fue 0.49. Así, ambos tipos de marcadores mostraron diversidad genética entre las variedades, distinguiendo a cada una de ellas. Los dendrogramas de los marcadores morfológicos e ISSR fueron notablemente similares, existiendo una correlación positiva entre ellos (R=0.30) y, en ambos casos, hubo una relación de las nueve variedades según su origen geográfico. Sin embargo, los marcadores ISSR fueron más efectivos, pues con un solo iniciador se distinguió a todas las variedades de T. pavonia. Se concluye que los marcadores ISSR son una herramienta útil para la discriminación rigurosa de genotipos y que se pueden usar de manera complementaria a la caracterización morfológica
Analysis of repoductive seasonality in Entrepelado and Retinto Iberian pig varieties under intensive management
[EN] Seasonal patterns in the farrowing distribution of two Iberian pig varieties (Retinto and Entrepelado) and its environmental and genetic sources of variation were analyzed within the context of a von Mises circular mixed model solved through Bayesian inference. Estimates about the dispersion parameter supported a low seasonal pattern for both Entrepelado and Retinto varieties with the farrowing peak located between March and April. Nevertheless, seasonality was corroborated by the deviance information criterion when comparing against a uniform circular model by the deviance information criterion (DIC); the uniform model increased more than 100 DIC units in both Iberian pig varieties. Regarding systematic effects, only the parity number of the sow had a relevant impact on farrowing distribution, advancing the farrowing peak in gilts and old sows. Genetic variability was only suggested in the Retinto population although with a small estimate, which would indicate little chance to modify farrowing distribution by genetic selection in the Iberian pig.Research supported by projects CGL2016-80155-R and IDI20170304, and a fellowship granted to M. Martin de Hijas-Villalba (BES-2017-080596) by Spain's Ministerio de Economia y Competitividad.Martin De Hijas-Villalba, M.; Varona, L.; Ibáñez-Escriche, N.; Pablo Rosas, J.; Luis Noguera, J.; Casellas, J. (2021). Analysis of repoductive seasonality in Entrepelado and Retinto Iberian pig varieties under intensive management. Livestock Science. 245:1-4. https://doi.org/10.1016/j.livsci.2021.1044411424
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