30 research outputs found

    Verticillium wilt of olive in the Guadalquivir Valley (southern Spain): relations with some agronomical factors and spread of Verticillium dahliae

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    Verticillium wilt of olive (VWO) is now the most destructive olive disease in the Guadalquivir valley in Andalucía (southern Spain). Disease surveys, conducted to assess the association of agronomical and geographical factors with the current spread of the disease, have shown that VWO is widespread in the valley, with a mean disease incidence (DI) in infested plots reaching 20.4%  (9000 inspected trees), but with significant differences among the provinces surveyed (25.7, 23.7 and 12%, for Jaén, Córdoba and Seville, respectively). The DI was significantly higher in irrigated (20.7%) than in dry-farming (18.3%) orchards, and also higher in non-tilled orchards (25.6%) than in regularly-tilled orchards (16.3%). The DI was likewise significantly lower for tree densities above 200 trees ha-1; and it was higher (21.5%) when the orchards were located near areas where other V. dahliae host plants were cultivated, than if the orchards were surrounded by non-host plants (11.9%). Lastly, the DI was significantly higher in plots where the tree were less than 25 year old and in plantations close to the Guadalquivir River (less than 10 km). ‘Picual’ was the cultivar most often affected with the disease, reaching a DI of 41.9% in orchards where this cultivar was grown. Highly virulent defoliating (D) isolates in the plantation surveyed were significantly more common (67.7%) than non-defoliating (ND) isolates (32.3%). These factors could explain the substantial increase in incidence and severity of VWO seen in the valley during the last decade

    Factores de riesgo relacionados al bullying en los estudiantes de la Universidad Nacional José Faustino Sánchez Carrión

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    En: Big Bang faustiniano : revista de investigación científica, Vol. 4, No. 2, pp. 42-45Objetivo: Identificar los factores de riesgo significativos del bullying en los estudiantes de la Universidad Nacional José Faustino Sánchez Carrión de Huacho. Métodos: La población estuvo conformada por 11000 estudiantes matriculados en el semestre académico 2014-I en la Sede de Huacho de las 12 Facultades y se tomó un muestreo aleatorio simple de 260 estudiantes. Los instrumentos utilizados para la recopilación de datos fueron, el bullying la escala de Lyn Quine adecuado al contexto universitario mediante una escala de autoreporte, según Quine (2003) esta escala permite estimar el comportamiento persistente, ofensivo, abusivo intimidatorio, malicioso o insultante, abuso de poder lo cual hace que el receptor se sienta perturbado, amenazado, humillado o vulnerable afectando su integridad personal y para la disfunción familiar se empleó la ficha técnica del Doctor Smilkstein, Gabriel evaluando cinco funciones básicas: adaptación, participación, ganancia, afecto y recursos. Resultados: El 43,1% fueron estudiantes varones y 56,9% mujeres; sus edades estuvieron comprendidas entre 16 y 27 años siendo el promedio 19 años, el 21,2 % de los estudiantes han sufrido de bullying y el nivel de disfunción familiar distribuido: Grave, 10,8%; Leve con un 29,2% y Familia Funcional con 60,0%. Conclusiones: La edad está relacionada con la presencia del bullying verbal y la disfunción familiar con la presencia del bullying psicológico con un nivel de confianza del 95%. El factor de riesgo asociado al bullying en el género femenino fue la disfunción familiar

    Martian Atmospheric Aerosols Composition and Distribution Retrievals During the First Martian Year of NOMAD/TGO Solar Occultation Measurements: 2. Extended Results, End of MY 34 and First Half of MY 35

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    This is the second part of Stolzenbach et al. (2023, https://doi.org/10.1029/2022JE007276), named hereafter Paper I, extends the period to the end of MY 34 and the first half of MY 35. This encompasses the end phase of the MY 34 Global Dust Storm (GDS), the MY 34 C-Storm, the Aphelion Cloud Belt (ACB) season of MY 35, and an unusual early dust event of MY 35 from LS_S 30° to LS_S 55°. The end of MY 34 overall aerosol size distribution shows the same parameters for dust and water ice to what was seen during the MY 34 GDS. Interestingly, the layered water ice vertical structure of MY 34 GDS disappears. The MY 34 C-Storm maintains condition like the MY 34 GDS. A high latitude layer of bigger water ice particles, close to 1 μm, is seen from 50 to 60 km. This layered structure is linked to an enhanced meridional transport characteristic of high intensity dust event which put the MY 34 C-Storm as particularly intense compared to non-GDS years C-Storms as previously suggested by Holmes et al. (2021, https://doi.org/10.1016/j.epsl.2021.117109). Surprisingly, MY 35 began with an unusually large dust event (Kass et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AGUFMP039…01K) found in the Northern hemisphere during LS_S 35° to LS_S 50°. During this dust event, the altitude of aerosol first detection is roughly equal to 20 km. This is close to the values encountered during the MY 34 GDS, its decay phase and the C-Storm of the same year. Nonetheless, no vertical layered structure was observed

    Martian Atmospheric Aerosols Composition and Distribution Retrievals During the First Martian Year of NOMAD/TGO Solar Occultation Measurements: 1. Methodology and Application to the MY 34 Global Dust Storm

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    Since the beginning of the Trace Gas Orbiter (TGO) science operations in April 2018, its instrument “Nadir and Occultation for MArs Discovery” (NOMAD) supplies detailed observations of the IR spectrums of the Martian atmosphere. We developed a procedure that allows us to evaluate the composition and distribution\u27s parameters of the atmospheric Martian aerosols. We use a retrieval program (RCP) in conjunction with a radiative forward model (KOPRA) to evaluate the vertical profile of aerosol extinction from NOMAD measurements. We then apply a model/data fitting strategy of the aerosol extinction. In this first article, we describe the method used to evaluate the parameters representing the Martian aerosol composition and size distribution. MY 34 GDS showed a peak intensity from LS_S 190° to 210°. During this period, the aerosol content rises multiple scale height, reaching altitudes up to 100 km. The lowermost altitude of aerosol\u27s detection during NOMAD observation rises up to 30 km. Dust aerosols reff_{eff} were observed to be close to 1 μm and its νeff_{eff} lower than 0.2. Water ice aerosols reff_{eff} were observed to be submicron with a νeff_{eff} lower than 0.2. The vertical aerosol structure can be divided in two parts. The lower layers are represented by higher reff_{eff} than the upper layers. The change between the lower and upper layers is very steep, taking only few kilometers. The decaying phase of the GDS, LS 210°–260°, shows a decrease in altitude of the aerosol content but no meaningful difference in the observed aerosol\u27s size distribution parameters

    Martian Atmospheric Aerosols Composition and Distribution Retrievals During the First Martian Year of NOMAD/TGO Solar Occultation Measurements: 1. Methodology and Application to the MY 34 Global Dust Storm

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    Since the beginning of the Trace Gas Orbiter (TGO) science operations in April 2018, its instrument “Nadir and Occultation for MArs Discovery” (NOMAD) supplies detailed observations of the IR spectrums of the Martian atmosphere. We developed a procedure that allows us to evaluate the composition and distribution's parameters of the atmospheric Martian aerosols. We use a retrieval program (RCP) in conjunction with a radiative forward model (KOPRA) to evaluate the vertical profile of aerosol extinction from NOMAD measurements. We then apply a model/data fitting strategy of the aerosol extinction. In this first article, we describe the method used to evaluate the parameters representing the Martian aerosol composition and size distribution. MY 34 GDS showed a peak intensity from LS 190° to 210°. During this period, the aerosol content rises multiple scale height, reaching altitudes up to 100 km. The lowermost altitude of aerosol's detection during NOMAD observation rises up to 30 km. Dust aerosols reff were observed to be close to 1 μm and its νeff lower than 0.2. Water ice aerosols reff were observed to be submicron with a νeff lower than 0.2. The vertical aerosol structure can be divided in two parts. The lower layers are represented by higher reff than the upper layers. The change between the lower and upper layers is very steep, taking only few kilometers. The decaying phase of the GDS, LS 210°–260°, shows a decrease in altitude of the aerosol content but no meaningful difference in the observed aerosol's size distribution parameters

    Optical and radiometric models of the NOMAD instrument part II: The infrared channels - SO and LNO

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