272 research outputs found

    The Effect of X-Rays on Cytological Traits of Tuta absoluta (Lepidoptera: Gelechiidae)

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    The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most important pests of tomato. With the purpose of developing environmentally friendly control tactics such as the inherited sterility (IS) technique against this species, it is essential to understand its genetics and biology. In this paper we analyzed the karyotype, sperm morphology and sperm ratio in wild-type and X-ray irradiated individuals of T. absoluta. The diploid chromosome number of T. absoluta was 2n = 58 including the pair of sex chromosomes: ZZ in males and WZ in females, which were the largest elements of the complement. Irradiation of pupae in an X-ray machine with a dose of 200 Gy generated various types of chromosomal rearrangements including translocations and fragmentations, resulting in altered chromosome numbers. The analysis of spermatozoa in T. absoluta revealed a significant morphological difference between apyrene and eupyrene sperm bundles. Irradiation with X-ray doses of 100, 150, 200 and 250 Gy did not have a significant effect on the apyrene to eupyrene sperm ratio. However, males irradiated with 300 Gy produced significantly more apyrene sperm than non-irradiated males. All the doses applied influenced the morphology of eupyrene sperm bundles. The modified eupyrene sperm bundles could be used as a bioindicator during the monitoring of an IS program after the release of irradiated males. We found that the modified eupyrene spermatozoa were transferred to the bursae copulatrices of the females. Males treated with 200 Gy transferred a greater proportion of modified eupyrene sperm than untreated males. The results presented herein provide essential information on the cytology of T. absoluta, which is required to evaluate the quality of the released insects, and for better understanding and application of IS against this economically important pest.Fil: Carabajal Paladino, Leonela Zusel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ceske Budejovice; República ChecaFil: Ferrari, María Edith. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Lauría, Juan P.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Cagnotti, Cynthia Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Síchová, Jindra. Ceske Budejovice; República Checa. University of South Bohemia; República ChecaFil: López, Silvia Noelí. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; Argentin

    Biology of Tupiocoris cucurbitaceus (Hemiptera: Miridae), a predator of the greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) in tomato crops in Argentina

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    The predator Tupiocoris cucurbitaceus is frequently found attacking Trialeurodes vaporariorum in greenhouses without pesticide applications in Argentina. The objective of these studies was to evaluate some biological characteristics of this species fed on three types of diet (whitefly nymphs, Sitotroga cerealella eggs and a mixed of both) and on two host plants (tomato and tobacco), under controlled experimental conditions. Preimaginal developmental time for female and male bugs was shorter in the presence of whiteflies than with only moth eggs. Females lived longer when they eat only whitefly nymphs compared to a mixed diet or only moth eggs. The amount of adult descendants was greater when bugs could eat whiteflies, regardless of the presence of S. cerealella. Embryonic development time, male longevity and sex proportion were not affected by the diet or the host plant. Prey consumption was evaluated for three T. cucurbitaceus life history stages (4th/5th instar nymphs, female and male adults) on two types of prey (whitefly nymphs and S. cerealella eggs). On tomato, females were more voracious than males and nymphs. On tobacco, adults and nymphs consumed more S. cerealella than T. vaporariorum nymphs, but again, bug females preyed more than males and nymphs. Results demonstrate that T. cucurbitaceus can survive, develop and reproduce normally using both T. vaporariorum and S. cerealella eggs as prey on tobacco or tomato plants. This information can be useful for managing this predator against T. vaporariorum through conservative or augmentative biological control strategies.Fil: López, Silvia Noemí. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rojas, Fresy Arce. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Velásquez, Vladimir Villalba. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Cagnotti, Cynthia Lorena. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Estructura de un sistema de un control de inventarios para el Gobierno Municipal del cantón Morona 2015

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    Estructura de un Sistema de Control de Inventarios para el Gobierno Municipal del Cantón Morona 2015. Las herramientas que se utilizó en el trabajo de investigación fue a través del método deductivo el cual es un método científico q considera q la conclusión es implícita en las premisas por tanto supone q las conclusiones sigue necesariamente a las premisas. Mientras que el método inductivo es un método científico q obtiene conclusiones generales a partir de premisas particulares. Dentro de las técnicas que se utilizo es la Observación Directa esta fue utilizada con mayor importancia porque se realizó un trabajo de campo continuo para determinar las influencias q intervienen en este fenómeno. Las Encuestas se lo realizaron a los funcionarios y empleados del Gobierno Autónomo Descentralizado del Cantón Morona. El resultado que se obtuvo en el Gobierno Autónomo Descentralizado de Cantón Morona es que no aplican con el Reglamento de Administración de los Bienes de Larga Duración y las Normas de la Contraloría General del Estado. Se recomienda la utilización de la presente propuesta del Sistema de Control de Inventarios como herramienta para el mejor manejo de los bienes institucionales.The present research was to make a Structure of Inventory Control System for Municipal Government from Morona canton 2015. The tools used research were through the deductive method which is a scientific method that the conclusion is implicit in the premises by both inductive means is a scientific method to get general conclusions from particular premises. Among the techniques used in the direct observation was used more important because a continuous field work was conducted to determine the influences involved in this phenomenon. Surveys officials and employees at Autonomous Government Decentralized performed from Morona canton. The result obtained in this Municipality does not apply to the Financial Rules of durable goods and the rules of the State Comptroller. It is recommended to use this proposal Inventory Control System as a tool for better management at Institutional assets

    A study of the strategies to enhance french i students’ writing skill at the Western Multidisciplinary Campus of the University of El Salvador during semester I, 2019

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    The research work A STUDY OF THE STRATEGIES TO ENHANCE FRENCH I STUDENTS´ WRITING SKILL AT THE WESTERN MULTIDISCIPLINARY CAMPUS OF THE UNIVERSITY OF EL SALVADOR aimed to determine which strategies can be implemented to help French I students of Licenciatura en Idioma Inglés, Opción Enseñanza at the Western Multidisciplinary Campus of the University of El Salvador improve their writing skill during semester I, 201

    NGC 6153: Reality is complicated

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    We study the kinematics of emission lines that arise from many physical processes in NGC 6153 based upon deep, spatially-resolved, high resolution spectra acquired with the UVES spectrograph at the ESO VLT. Our most basic finding is that the plasma in NGC 6153 is complex, especially its temperature structure. The kinematics of most emission lines defines a classic expansion law, with the outer part expanding fastest (normal nebular plasma). However, the permitted lines of \ion{O}{1}, \ion{C}{2}, \ion{N}{2}, \ion{O}{2}, and \ion{Ne}{2} present a constant expansion velocity that defines a second kinematic component (additional plasma component). The physical conditions imply two plasma components, with the additional plasma component having lower temperature and higher density. The [\ion{O}{2}] density and the [\ion{N}{2}] temperature are anomalous, but may be understood considering the contribution of recombination to these forbidden lines. The two plasma components have very different temperatures. The normal nebular plasma appears to be have temperature fluctuations in part of its volume (main shell), but only small fluctuations elsewhere. The additional plasma component contains about half of the mass of the N2+^{2+} and O2+^{2+} ions, but only 353-5\% of the mass of H+^+ ions, so the two plasma components have very different chemical abundances. We estimate abundances of 12+log(O2+/H+)9.212+\log(\mathrm O^{2+}/\mathrm H^+)\sim 9.2\,dex and He/H0.13\mathrm{He}/\mathrm H\sim 0.13. Although they are all complications, multiple plasma components, temperature fluctuations, and the contributions of multiple physical processes to a given emission line are all part of the reality in NGC 6153, and should generally be taken into account.Comment: 55 pages, 51 figures, 9 tables, accepted for publication in The Astronomical Journa

    Propuesta de una metodologí­a basada en el COSO II. Aplicación a un caso práctico

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    El presente artí­culo tiene como objetivo proponer una metodologí­a de evaluación y análisis  del control interno basado en la Enterprise Risk Management - Integrated Framework - COSO II, el cual servirá como una herramienta de medición y valoración   del riesgo de la gestión administrativas que existe en la ejecución de los procedimientos de la organización.La metodologí­a a emplear identificará los eventos potenciales que afectan a la organización, a su vez que evaluará  y responderá a los riesgos detectado, mediante la aplicación de un cuestionario basado en los componentes del COSO II esté permitirá valorar los riesgos existentes en la organización y evaluar la eficiencia de los controles establecidos, a fin de se logre los objetivos trazados.La metodologí­a COSO II identificó la existencia de los riesgos de control interno en el área administrativa por lo que se debe diseñar estrategia de mejora e implementar decisiones de respuesta al riesgo, esto optimizará la utilización de los recursos mediante el aprovechamiento de las oportunidades y disminuyendo las amenazas.La metodologí­a aplicada permite conocer el nivel de riesgo existente para poder establecer planes de mejora con relación a la eficacia, eficiencia en el uso de los recursos y la consecución de los objetivos organizacionales mediante la determinación de las fortalezas y debilidades de la organización

    Effects of X-rays on Tuta absoluta for use in inherited sterility programmes

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    Tuta absoluta is a key pest of tomato crops originating from South America. The consequences of X-radiation on this species were studied under laboratory controlled conditions. The effect of radiation on adult emergence was evaluated exposing male and female pupae to increasing X-rays. Adult emergence decreased as doses of X-radiation increased, with the appearance of deformities such as malformed wings and bent legs at doses C350 Gy. Besides, males and females obtained from irradiated pupae were out crossed with untreated counterparts to explore the effects of X-radiation on inherited sterility. (a) Irradiated male 9 untreated female crosses. Both fecundity and fertility of the untreated females were reduced by radiation, and the effect was stronger as the doses increased. Neither the longevity of parental males and F1 adults nor the sex ratios of the F1 and F2 generations were affected by X-radiation (F1 and F2: first and second generation of descendants of irradiated adults). Inherited sterility effects weremanifested by a significant reduction in the F1 fecundity, F1 fertility, and the amount of larvae and pupae produced. Doses of 200?250 Gy could be used to induce inherited sterility in T. absoluta males. (b) Untreated male 9 irradiated female crosses. The minimum dose at which irradiated females were completely sterile was 200 Gy. The present study is the first study in T. absoluta that provides the starting point for implementing the inherited sterility in this species.Fil: Cagnotti, Cynthia Lorena. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Viscarret, Mariana Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Riquelme, Maria B.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Botto, Eduardo Norberto. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Carabajal Paladino, Leonela Zusel. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Segura, Diego Fernando. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: López, Silvia N.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; Argentin

    Evaluation of Toll-like-receptor gene family variants as prognostic biomarkers in rheumatoid arthritis

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    Rheumatoid arthritis (RA) is a systemic autoimmune disease whose main feature is persistent joint inflammation. Toll-like receptors (TLRs) play critical roles in the activation of innate and adaptive immune responses, and influence the activity of NF?B, a key player in chronic inflammation. We aimed at investigating the association of TLR allelic variants with susceptibility and severity of RA through a systematic, high-throughput, analysis of TLR genes. All coding exons and flanking regions of nine members of the TLR family (TLR1-9) were analyzed in 66 patients with RA and 30 healthy controls by next generation sequencing. We focussed on three single allelic variants, N248S in TLR1, Q11L in TLR7 and M1V in TLR8 based on the allelic frequencies in both patient and control populations, the predicted impact on protein function and the novelty in RA research. Analysis of these selected variants in a larger cohort of 402 patients with RA and in 208 controls revealed no association with susceptibility. However, the M1V allele was associated with a lower need for disease-modifying antirheumatic drugs (DMARDs) (p =0.008) and biologic treatments (p =0.021). Functional studies showed that the M1V variant leads to a reduced production of inflammatory cytokines, IL-1?, IL-6 and TNF?, in response to TLR8 agonists. Thus, the presence of this variant confers a significant protective effect on disease severity. These results show for the first time the association between the M1V variant of TLR8 and reduced disease severity in RA, which could have prognostic value for these patients.This work was supported by the Instituto de Salud Carlos III (ISCIII), Spanish Ministry of Science and Innovation grant PI11/02012, and grant RD12/0036/0022 from Red Temática de Investigación Cooperativa en Cáncer, Sociedad Española de Reumatología grant FER13/13 and Instituto de Investigación Valdecilla (IDIVAL) grant APG-03. I.V. is funded by programa Ramón y Cajal, Ministerio de Economia y Competitividad, Spain
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