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Phylo‐biogeographical distribution of whitefly Bemisia tabaci (Insecta: Aleyrodidae) mitotypes in Ecuador
Abstract The Bemisia tabaci complex in Ecuador was studied with respect to phylogenetic relationships and eco‐geographical distribution. Whitefly samples were collected from natural and agricultural environments in nine provinces of Ecuador (latitude, 2° N–5° S; longitude, 78°–81° W). Mitotypes were identified based on phylogenetic analysis of the 3′‐mtCOI‐tRNAleu region (832 bp) and corrected pairwise distance analysis. The distribution of mitotypes was modeled using MaxEnt, and their predicted niches were characterized according to environmental gradients. Four B. tabaci mitotypes were identified, of which three are endemic, herein ECU1–3, and the other is the introduced B mitotype. Mitotypes ECU1 (44%), ECU2 (0.74%), and ECU3 (1.47%) grouped in the American Tropics (AMTROP) species and diverged by as much as 10%, which was higher than previous estimates for the AMTROP clade of 7–8.6%. Although haplotypes of ECU1 and ECU2 are known from the American Tropics, this is the first report of the ECU3 mitotype, which may possibly be restricted to southern Ecuador. The distribution of the three ECU‐endemic mitotypes spanned the high‐altitude niches of the western slope of the Andes, rich in microclimates with variable temperature and humidity conditions. The non‐endemic B mitotype (47%) occurred only in the irrigated cropping systems located in hot and/or dry‐tropical ecological niches. Of the endemic mitotypes, ECU1 occupied the most ecological niches. Among variables contributing to ECU1 and B mitotype niche range assignments, the most significant to influence ecological range was rainfall. The B. tabaci endemic to Ecuador were more diverse with respect to mtCOI‐tRNAleu sequence than previously known, and occupied distinct microclimate niches suggestive of ecological resilience
Estudio preliminar de la capacidad de dos especies de áfidos para transmitir el virus del mosaico de la calabaza (sqmv) en melón bajo condiciones de invernadero e identificación de sus enemigos naturales.
Se estudió de forma preliminar la capacidad de dos especies de pulgones para transmitir el virus del mosaico de la calabaza (SqMV) y se identificaron sus enemigos naturales. El estudio se realizó en las localidades de Pedro Carbo, Virgen de Fátima y Pechiche. Se corroboró la identidad del virus mediante la prueba de ELISA-DAS y se mantuvo la fuente de inóculo en plantas de Cucumis melo y Cucurbita pepo. Para la identificación de los pulgones se observaron estructuras de la cabeza, corniculos y cauda y se instalaron colonias de Aphis gossypii sobre plantas de melón y de Myzus persicae sobre pimiento. Para los ensayos de transmisión se emplearon cinco minutos en los periodos de adquisición e inoculación, previo a una hora de ayuno. La identificación de los enemigos naturales se realizó utilizando bases de datos y colecciones sinópticas internacionales. Se comprobó la presencia del virus del mosaico de la calabaza en las zonas de Pedro Carbo y Pechiche; además, en los ensayos preliminares realizados, la transmisión con A. gossypii resultó positiva en un porcentaje de 10, 84% ± 0,031, no así con M. persicae. La transmisión en los controles fue nula. Se identificaron 12 depredadores, un parasitoide y dos entomopatógenos; se destaca la infección de pulgones por Nomuraea rileyi –hospederos que se reportan por primera vezESPO
Candidate counterparts to the soft gamma-ray flare in the direction of LS i +61 303
Context. A short duration burst reminiscent of a soft gamma-ray repeater/anomalous X-ray pulsar behaviour was detected in the direction of LS I +61 303 by the Swift satellite. While the association with this well known gamma-ray binary is likely, a different origin cannot be excluded.
Aims. We explore the error box of this unexpected flaring event and establish the radio, near-infrared and X-ray sources in our search for any peculiar alternative counterpart.
Methods. We carried out a combined analysis of archive Very Large Array radio data of LS I +61 303 sensitive to both compact and extended emission. We also reanalysed previous near infrared observations with the 3.5 m telescope of the Centro Astronómico Hispano Alemn and X-ray observations with the Chandra satellite.
Results. Our deep radio maps of the LS I +61 303 environment represent a significant advancement on previous work and 16 compact radio sources in the LS I +61 303 vicinity are detected. For some detections, we also identify near infrared and X-ray counterparts. Extended emission features in the field are also detected and confirmed. The possible connection of some of these sources with the observed flaring event is considered. Based on these data, we are unable to claim a clear association between the Swift-BAT flare and any of the sources reported here. However, this study represents the most sophisticated attempt to determine possible alternative counterparts other than LS I +61 303.Facultad de Ciencias Astronómicas y Geofísica
Candidate counterparts to the soft gamma-ray flare in the direction of LS i +61 303
Context. A short duration burst reminiscent of a soft gamma-ray repeater/anomalous X-ray pulsar behaviour was detected in the direction of LS I +61 303 by the Swift satellite. While the association with this well known gamma-ray binary is likely, a different origin cannot be excluded.
Aims. We explore the error box of this unexpected flaring event and establish the radio, near-infrared and X-ray sources in our search for any peculiar alternative counterpart.
Methods. We carried out a combined analysis of archive Very Large Array radio data of LS I +61 303 sensitive to both compact and extended emission. We also reanalysed previous near infrared observations with the 3.5 m telescope of the Centro Astronómico Hispano Alemn and X-ray observations with the Chandra satellite.
Results. Our deep radio maps of the LS I +61 303 environment represent a significant advancement on previous work and 16 compact radio sources in the LS I +61 303 vicinity are detected. For some detections, we also identify near infrared and X-ray counterparts. Extended emission features in the field are also detected and confirmed. The possible connection of some of these sources with the observed flaring event is considered. Based on these data, we are unable to claim a clear association between the Swift-BAT flare and any of the sources reported here. However, this study represents the most sophisticated attempt to determine possible alternative counterparts other than LS I +61 303.Facultad de Ciencias Astronómicas y Geofísica
Radio detections towards unidentified variable EGRET sources
Context. A considerable fraction of the -ray sources discovered with the Energetic Gamma-Ray Experiment Telescope (EGRET) remain unidentified. The EGRET sources that have been properly identified are either pulsars or variable sources at both radio and gamma-ray wavelengths. Most of the variable sources are strong radio blazars. However, some low galactic-latitude EGRET sources, with highly variable -ray emission, lack any evident counterpart according to the radio data available until now.
Aims. The primary goal of this paper is to identify and characterise the potential radio counterparts of four highly variable -ray sources in the galactic plane through mapping the radio surroundings of the EGRET confidence contours and determining the variable radio sources in the field whenever possible.
Methods. We have carried out a radio exploration of the fields of the selected EGRET sources using the Giant Metrewave Radio Telescope (GMRT) interferometer at 21 cm wavelength, with pointings being separated by months.
Results. We detected a total of 151 radio sources. Among them, we identified a few radio sources whose flux density has apparently changed on timescales of months. Despite the limitations of our search, their possible variability makes these objects a top-priority target for multiwavelength studies of the potential counterparts of highly variable, unidentified gamma-ray sources.Facultad de Ciencias Astronómicas y GeofísicasInstituto Argentino de Radioastronomí
The star forming region Monoceros R2 as a gamma-ray source
Context. After the release of the gamma-ray source catalog produced by the Fermi satellite during its first two years of operation, a significant fraction of sources still remain unassociated at lower energies. In addition to well-known high-energy emitters (pulsars, blazars, supernova remnants, etc.), theoretical expectations predict new classes of gamma-ray sources. In particular, gamma-ray emission could be associated with some of the early phases of stellar evolution, but this interesting possibility is still poorly understood.
Aims. The aim of this paper is to assess the possibility of the Fermi gamma-ray source 2FGL J0607.5-0618c being associated with the massive star forming region Monoceros R2.
Methods. A multi-wavelength analysis of the Monoceros R2 region is carried out using archival data at radio, infrared, X-ray, and gamma-ray wavelengths. The resulting observational properties are used to estimate the physical parameters needed to test the different physical scenarios.
Results. We confirm the 2FGL J0607.5-0618c detection with improved confidence over the Fermi two-year catalog. We find that a combined effect of the multiple young stellar objects in Monoceros R2 is a viable picture for the nature of the source.Facultad de Ciencias Astronómicas y GeofísicasInstituto Argentino de Radioastronomí
N=1 SQCD-like theories with N_f massive flavors from AdS/CFT and beta functions
We study new supergravity solutions related to large-
supersymmetric gauge field theories with a large number of massive
flavors. We use a recently proposed framework based on configurations with
color D5 branes and a distribution of flavor D5 branes, governed by
a function . Although the system admits many solutions, under
plausible physical assumptions the relevant solution is uniquely determined for
each value of . In the IR region, the solution smoothly
approaches the deformed Maldacena-N\'u\~nez solution. In the UV region it
approaches a linear dilaton solution. For the gauge coupling
function computed holographically is negative definite, in the UV approaching
the NSVZ function with anomalous dimension
(approaching )), and with in
the IR. For , has a UV fixed point at strong coupling,
suggesting the existence of an IR fixed point at a lower value of the coupling.
We argue that the solutions with describe a "Seiberg dual" picture where
flips sign.Comment: 18 pages, 10 figure
The star forming region Monoceros R2 as a gamma-ray source
Context. After the release of the gamma-ray source catalog produced by the Fermi satellite during its first two years of operation, a significant fraction of sources still remain unassociated at lower energies. In addition to well-known high-energy emitters (pulsars, blazars, supernova remnants, etc.), theoretical expectations predict new classes of gamma-ray sources. In particular, gamma-ray emission could be associated with some of the early phases of stellar evolution, but this interesting possibility is still poorly understood.
Aims. The aim of this paper is to assess the possibility of the Fermi gamma-ray source 2FGL J0607.5-0618c being associated with the massive star forming region Monoceros R2.
Methods. A multi-wavelength analysis of the Monoceros R2 region is carried out using archival data at radio, infrared, X-ray, and gamma-ray wavelengths. The resulting observational properties are used to estimate the physical parameters needed to test the different physical scenarios.
Results. We confirm the 2FGL J0607.5-0618c detection with improved confidence over the Fermi two-year catalog. We find that a combined effect of the multiple young stellar objects in Monoceros R2 is a viable picture for the nature of the source.Facultad de Ciencias Astronómicas y GeofísicasInstituto Argentino de Radioastronomí
Isolation, Characterization, and Biotechnological Potential of Native Microalgae From the Peruvian Amazon
The objective of this chapter is to provide scientific information on basic aspects to be taken into account to achieve the successful isolation, biochemical, and molecular characterization and then to evaluate the biotechnological potential of native microalgae of the Peruvian Amazon. Recent investigations reported by our research team has demonstrated that the isolated native microalgae from the Peruvian Amazon have a great potential for the biotechnological production of biodiesel and nutraceuticals. This biotechnological potential was identified thanks to the application of various protocols that were standardized by the authors over the last 5 years. In conclusion, the native microalgae of the Peruvian Amazon have biotechnological potential and are therefore promising for the production of both biodiesel and nutraceuticals. Various species of microalgae were identified, isolated, cultured, and characterized using biochemical, nutraceutical, and molecular techniques, the isolation stage being the starting point to achieve various biotechnological applications. Ankistrodesmus sp. is one of the microalgae with potential for the production of biodiesel and microalgae such as Haematococcus pluvialis, Scenedesmus sp., and Chlorella sp., among others demonstrated a high potential for nutraceutical production. The stress conditions to which microalgae are subjected are being a determining factor for the production of biodiesel and nutraceuticals
Criterios geomorfológicos sobre actividad tectónica reciente a lo largo de la Costa Recta, Isla Decepción (Antártida Occidental)
Several active tectonic evidences are observed along Costa Recta, located eastward of Deception Island (western Antarctica): marine terraces and fluvial streams cutting a relict glacier. The height of both landforms decrease southward from Macaroni Point, appointing to a tilt movement across a fault plane. Fault planes were measured at Macaroni Point and Baily Head, with a main NNWSSE orientation, similar to the Costa Recta strike. From several scales o f measure, the orientation of the beach was established in two principal segments: N168QE, and N173QE. On the other hand, the beach and glacier dynamics and sedimentary deposits were studied. According to the morpho-tectonic analysis, we conclude that the Costa Recta beach is a retreat scarp of a submarine fault oriented NNW-SSE and located in the Bransfield Strait, although a geophysical study o f the marine bottom is needed to map the fault trace in an accurate way
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