913 research outputs found
Virulence of Spanish Phytophthora nicotianae isolates towards Capsicum annuum germplasm and pathogenicity towards Lycopersicum esculentum
The virulence of six northwestern Spanish Phytophthora nicotianae Breda de Haan isolates towards the pepper (Capsicum annuum) cultivars commonly used for the determination of P. capsici Leonian pathotype (SCM 334, PI201234 and Yolo Wonder), was similar to that of the latter oomycete but different to that of the German reference isolate P. nicotianae 411.87. When nine local C. annuum cultivars were inoculated with a P. nicotianae isolate of well known pathogenicity, the virulence recorded was significantly different to that recorded for P. capsici. Though the average level of resistance of the northwestern Spanish Capsicum germplasm to P. nicotianae was incomplete and weaker than that recorded for the SCM 334 and PI201234 cultivars, genotypes Co 12B and Co 3.25 showed high resistance to this oomycete. None of the six northwestern Spanish P. nicotianae isolates tested were pathogenic towards Lycopersicum esculentum cv. S. Pedro, unlike P. capsici, which produced clear collar and root rot in this host
Neutrino mixing and masses in a left-right model with mirror fermions
In the framework of a left-right model containing mirror fermions with gauge
group SU(3),
we estimate the neutrino masses, which are found to be consistent with their
experimental bounds and hierarchy. We evaluate the decay rates of the Lepton
Flavor Violation (LFV) processes , and . We obtain upper limits for the
flavor-changing branching ratios in agreement with their present experimental
bounds. We also estimate the decay rates of heavy Majorana neutrinos in the
channels , and , which are roughly equal for large values of the heavy
neutrino mass. Starting from the most general Majorana neutrino mass matrix,
the smallness of active neutrino masses turns out from the interplay of the
hierarchy of the involved scales and the double application of seesaw
mechanism. An appropriate parameterization on the structure of the neutrino
mass matrix imposing a symmetric mixing of electron neutrino with muon and tau
neutrinos leads to Tri-bimaximal mixing matrix for light neutrinos.Comment: Accepted by European Physical Journal
On the noncommutative eikonal
We study the eikonal approximation to quantum mechanics on the Moyal plane.
Instead of using a star product, the analysis is carried out in terms of
operator-valued wavefunctions depending on noncommuting, operator-valued
coordinates.Comment: 18 page
Elementos escasos y mineralizaciones metálicas en neises de la provincia de Pontevedra
[Resumen] Se estudió el contenido total, y en minerales no silicatédos, de Ni, Cu, Co, 2P y Ti en doce muestras representativas de los neises existentes en la provincia de Pontevedra. Se estableció la mineralogía y composición de Ios compuestos metálicos demostrándose la existencia de minerales de Ti en todas las muestras, en la mayoría rutilo con pequeñas cantidades de Fe en solucién sólida En otras apaecren cristales de ilmenita con Mn y Mg en solucién sólida al alguna de ellas. Se ha detectado la aparición de cristales de tumalina en la nuestra de neis glandular. Se han establecido las f ómuIas mineralógicas de todas las mineralizaciones metálicas localizada
Las sociedades científicas de estudiantes de odontología: una fuerza motriz para la investigación.
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Neutrino masses and mixing parameters in a left-right model with mirror fermions
In this work we consider a left-right model containing mirror fermions with
gauge group SU(3). The model has several free parameters which here we have
calculated by using the recent values for the squared-neutrino mass
differences. Lower bound for the mirror vacuum expectation value helped us to
obtain crude estimations for some of these parameters. Also we estimate the
order of magnitude of the masses of the standard and mirror neutrinos.Comment: 13 pages, version submitted to European Physical Journal
Influencia del acondicionamiento de la dentina con ácido poliacrílico en la resistencia al cizallamiento de un cemento de ionómero de vidrio modificado con resina con tecnología de nano relleno.
Purpose: This in vitro study aimed to evaluate the influence of dentin conditioning with polyacrylic acid on the shear bond strength of the nano-filled resin-modified glass ionomer cement Ketac N100 (3MESPE). Material and methods: Eighteen bovine incisors were randomly divided into two groups (n=18): group 1, without dentin surface treatment, and group 2, with dentin surface treated with 10% polyacrylic acid for 15 seconds. In both groups the primer was applied before the application of the nano-filled resin-modified glass ionomer cement (Ketac N100) and light-cured for 20 seconds. After 24 hours, the specimens were submitted to thermocycling for 350 cycles, and the teeth were immersed in distilled water at room temperature. After 24 hours, specimens were tested for shear bond strength at 1mm/minute crosshead speed. The collected data were analyzed using the non-parametric test of Mann Whitney (p<0.05). Results: There was a significant difference in shear bond strength values between the treatment and control groups, the group with dentin conditioning with 10% polyacrylic acid showed higher shear strength values than the group without dentin treatment. Conclusion: Application of 10% polyacrylic acid on dentin increases the shear bond strength values of nano-filled resin-modified glass ionomer cement.Objetivo: Este estudio in vitro tuvo como objetivo evaluar la influencia del acondicionamiento de la dentina con ácido poliacrílico sobre la resistencia al cizallamiento del cemento de ionómero de vidrio modificado con resina con tecnología de nano relleno Ketac N100 (3MESPE). Material y Métodos: Dieciocho incisivos bovinos se dividieron aleatoriamente en dos grupos (n = 18): el grupo 1, sin tratamiento de la superficie dentinaria, y el grupo 2, con la superficie dentinaria tratada con ácido poliacrílico al 10% durante 15 segundos. En ambos grupos, el Primer se aplicó antes de la aplicación del cemento de ionómero devidrio modificado con resina con tecnología de nano relleno (Ketac N100) y se fotopolimerizó durante 20 segundos. Después de 24 horas, las muestras se sometieron a 350 ciclos de termociclado y los dientes se sumergieron en agua destilada a temperatura ambiente.Después de 24 horas, las muestras se evaluaron para determinar la resistencia al cizallamiento a una velocidad constante de 1 mm / minuto. Los datos recolectados fueron analizados mediante la prueba no paramétrica de Mann Whitney (p<0.05). Resultados: Hubo una diferencia significativa en los valores de resistencia al cizallamiento entre los grupos de tratamiento y control, el grupo con acondicionamiento de dentina con ácido poliacrílico al 10% mostró valores de resistencia al cizallamiento más altos que el grupo sin tratamiento de la dentina. Conclusión: La aplicación de ácido poliacrílico al 10% sobre la dentina aumenta los valores de resistencia al cizallamiento del cemento de ionómero de vidrio modificado con resina con tecnología de nano relleno
Comparing the generation of DTM in a forest ecosystem using TLS, ALS and UAV-DAP, and different software tools
[EN] Remote sensing and photogrammetry techniques have demonstrated to be an important tool for the characterization of forest ecosystems. Nonetheless, the use of these techniques requires an accurate digital terrain model (DTM) for the height normalization procedure, which is a key step prior to any further analyses. In this manuscript, we assess the extraction of the DTM for different techniques (airborne laser scanning: ALS, terrestrial laser scanning: TLS, and digital aerial photogrammetry in unmanned aerial vehicle: UAV-DAP), processing tools with different algorithms (FUSION/LDV© and LAStools©), algorithm parameters, and plot characteristics (canopy and shrub cover, and terrain slope). To do this, we compare the resulting DTMs with one used as reference and extracted from classic surveying measurements. Our results demonstrate, firstly, that ALS and reference DTMs are similar in the different scenarios, except for steep slopes. Secondly, TLS DTMs are slightly less accurate than those extracted for ALS, since items such as trunks and shrubs cause a great occlusion due to the proximity of the instrument, and some of the points filtered as ground correspond to these items as well, therefore a finer setting of algorithm parameters is required. Lastly, DTMs extracted for UAV-DAP in dense canopy scenarios have a low accuracy, however, accuracy may be enhanced by modifying the processing tool and algorithm parameters. An accurate DTM is essential for further forestry applications, therefore, to know how to take advantage of the available data to obtain the most accurate DTM is also fundamental.The authors are thankful for the financial support provided by the
Spanish Ministerio de Economía y Competitividad and FEDER,
in the framework of the project CGL2016-80705-R.Crespo-Peremarch, P.; Torralba, J.; Carbonell-Rivera, JP.; Ruiz Fernández, LÁ. (2020). Comparing the generation of DTM in a forest ecosystem using TLS, ALS and UAV-DAP, and different software tools. ISPRS. 575-582. https://doi.org/10.5194/isprs-archives-XLIII-B3-2020-575-2020S57558
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