Search

Your search keyword '"Castellanos, Ignacio"' showing total 146 results
Start Over Author "Castellanos, Ignacio"
146 results on '"Castellanos, Ignacio"'

21. Evaluation of predation risk by a caterpillar using substrate-borne vibrations

Author

Castellanos, Ignacio and Barbosa, Pedro

Subjects
Predation (Biology), Vibration, Zoology and wildlife conservation
Abstract

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2006.02.005 Byline: Ignacio Castellanos, Pedro Barbosa Abstract: Assessment of predation risk and appropriate defensive responses are critical for most organisms. Prey individuals must distinguish between the cues produced by abiotic factors, competitors and predators, and respond appropriately. We determined whether larvae of Semiothisa aemulataria (Geometridae), which defend themselves from invertebrate predators by hanging on a silk thread, can detect predator threats and distinguish between different predators, other herbivores and abiotic factors. Furthermore, we determined the mechanism used by the caterpillars to detect predator threats and the degree to which predation risk was specified. The hanging behaviour of S. aemulataria caterpillars occurred in response to invertebrate predators (wasps and stink bugs) but not in response to birds, other herbivores or abiotic factors. Caterpillars distinguish these predators by perceiving their substrate-borne vibrations. These vibrations differed both qualitatively and quantitatively. Caterpillars did not hang in response to mechanically reproduced vibration stimuli representing herbivores, but they did show this defensive behaviour in response to vibration stimuli that duplicated invertebrate predator signals. Caterpillars responded differently to predatory wasps and stink bugs. The length of the silk thread produced by caterpillars in response to foraging wasps was significantly greater than that produced in response to stink bugs. These predator-specific responses led to increased survival. Our results show that invertebrate prey are able to distinguish among the cues produced by abiotic factors, competitors and predators and respond specifically, in accordance with the potential risk posed by a predator. Author Affiliation: (a) Centro de Investigaciones Biologicas, Universidad Autonoma del Estado de Hidalgo, Mexico (a ) Department of Entomology, University of Maryland, College Park, U.S.A. Article History: Received 5 July 2004; Revised 17 September 2005; Accepted 8 February 2006 Article Note: (miscellaneous) MS. number: A9929

Published
2006

32. Cost efficiency and financial situation of local governments in the Canary Isles during the recession

Author

Prior Jiménez, Diego, Martín-Pinillos Castellanos, Ignacio de, Zafra Gómez, José Luis, Pérez López, Gemma, Prior Jiménez, Diego, Martín-Pinillos Castellanos, Ignacio de, Zafra Gómez, José Luis, and Pérez López, Gemma

Abstract

This paper examines cost efficiency in the Spanish municipal public sector, in a specific geographic area (the Canary Isles, Spain), with respect to financial condition and different types of municipal debt. The study focuses on municipalities dependent on tourism and on the consequences to them of the Great Recession, doing so via a two-stage analysis. In the first, the order-m method is used to evaluate the cost efficiency of 77 Canary Isles municipalities, for the period 2008-12. In the second stage, we examine the effect produced on cost efficiency by different types of borrowing (long term, short term, financial and commercial) together with other financial, economic, political and quality variables, using the model developed by Simar and Wilson (2007), based on a truncated bootstrap regression with panel data. Empirical analysis shows that in times of crisis there is a significant relationship between the components of financial condition and cost efficiency. In conclusion, municipal cost efficiency increases with commercial debt, but decreases with financial debt. Furthermore, certain socioeconomic variables affect the levels of cost efficiency., Este trabajo examina la eficiencia de costes para el caso particular del sector público municipal español, concretamente, para el caso de los municipios canarios, poniendo especial énfasis en áreas relacionadas con la condición financiera y diferentes tipologías de deuda, teniendo en cuenta las características propias que estos municipios poseen, como un índice turístico elevado. En primer lugar, se utiliza el método de orden m para evaluar la eficiencia de costes de 77 municipios de las Islas Canarias, para el período 2008-12. En la segunda etapa, examinamos el efecto producido en la eficiencia de costes por diferentes tipologías de endeudamiento (largo plazo, corto plazo, financiero y comercial) junto con otras variables financieras, económicas, políticas y de calidad, utilizando el modelo desarrollado por Simar y Wilson (2007), basado en una regresión truncada con datos de panel. Nuestro análisis empírico muestra que en tiempos de crisis existe una relación significativa entre los componentes de la condición financiera y la eficiencia de costes. En particular, concluye que mientras la eficiencia de los costes municipales aumenta con la deuda comercial, disminuye con la deuda financiera. Además, mostramos que ciertas variables socioeconómicas afectan los niveles de eficiencia de costes.

Published
2019

36. Preferencia y depredación de semillas de mezquite por escarabajos (Coleoptera: Bruchidae).

Author

de Jesús Parra-Gil, Pedro, Baltazar-Meneses, Karen, Castellanos, Ignacio, Romero-Nápoles, Jesús, Ángel Martínez-Morales, Miguel, and Arturo Cid-Becerra, Jorge

Subjects
SEED size, BRUCHIDAE, BEETLES, MESQUITE, OVIPARITY
Abstract

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2020
Full Text
View/download PDF

37. Effect of the internal size of the hive on brood, honey, and pollen production in Apis mellifera colonies in the central Mexican plateau.

Author

Hernández Carlos, Alfonso and Castellanos, Ignacio

Subjects
*HONEYBEES, *BEEHIVES, *ANIMAL clutches, *HONEY, *POLLEN, *ARID regions
Abstract

This study aimed to analyze the effect of the internal size on the strength (brood area) and productivity (honey and pollen areas) of the honeybee hives during the winter season in a semiarid region of the central Mexican plateau. Four Jumbo hive frames (45 x 28 cm) were used inside brood chambers with three internal sizes (52.2, 42.3, and 23.9 L), each chamber contained the same number of honeybees. Simultaneously, it was recorded the temperature inside the hives to determine if the brood chamber temperatures varied with the volume. The Jumbo hive, which is the largest hive, is the most used in the central Mexican plateau and showed the lowest strength and productivity values, as well as the lowest internal temperature. These results show that Jumbo hives can decrease the honey and pollen productivity for the central Mexican plateau beekeepers, which is why it is necessary to implement a practice or mechanism that allows maintaining strong beehives for the spring harvest. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

38. DESARROLLO DE UNA TIENDA VIRTUAL EMPLEANDO WORDPRESS Y WOOCOMMERCE PARA UNA EMPRESA COMERCIALIZADORA: CASO SERVICIOS PROFESIONALES DE SALUD.

Author

Morcillo Presenda, Freddy Alberto, Flores Lázaro, Carlos Mario, García Alcocer, Julio Humberto, Corona Ferreira, Arturo, Chapus Castañeda, Gustavo Adolfo, and Montecino Castellanos, Ignacio Antonio

Abstract

Copyright of Congreso Internacional de Investigacion Academia Journals is the property of PDHTech, LLC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2019

40. Bioerosion structures in Crepidula (Mollusca, Gastropoda) as indicators of latitudinal palaeoenvironmental changes: Example from the marine Quaternary of Argentina

Author

Davies Karen, Aguirre Marina, Farinati Ester, Castellanos Ignacio, and Richiano Sebastián

Subjects
PLEISTOCENE, Oceanography, SOUTHWESTERN ATLANTIC, Ciencias de la Tierra y relacionadas con el Medio Ambiente, Gastropoda, HOLOCENE, Crepidula, Mollusca, Ecology, Evolution, Behavior and Systematics, Holocene, Earth-Surface Processes, GEOGRAPHICAL VARIATIONS, biology, Ecology, Bioerosion, Entobia, Paleontology, biology.organism_classification, PALAEOCEANOGRAPHICAL CHANGES, Interglacial, Quaternary, Meteorología y Ciencias Atmosféricas, ICHNODIVERSITY, Geology, CIENCIAS NATURALES Y EXACTAS
Abstract

Late Quaternary marine skeletal concentrations from Argentina are rich in molluscs exhibiting a great variety of bioerosion structures. The shells of Crepidula, a characteristic gastropod occurring along more than 2000. km of coastline between the Río de La Plata margin and southern Patagonia, show traces of dwelling, predation and anchoring activities made by porifers, bryozoans, annelids, other gastropods and brachiopods. Caulostrepsis, Entobia, Maeandropolydora, Iramena, Oichnus, Finichnus, Pennatichnus, Pinaceocladichnus, Podichnus and Renichnus occur on the outer shell surface. Finichnus and Oichnus are the only traces present along the entire area and the full time span considered. The most characteristic structures are produced by bryozoans, polychaetes and predatory gastropods. Traces produced by annelids and predatory gastropods occur preferentially in the central shell sector, where predators gained access to the soft parts of the prey. By contrast, encrusting or branching bryozoan colonies are widely distributed as they can attach to any sector regardless of shell features available. No strict correlation is evident between ichnodiversity and either time or latitude, but ichnodiversity is linked to local oceanographical/biotic controls. For Patagonia, with a great majority of ichnotaxa made by bryozoans, the general trend of higher bioerosion degree and ichnodiversity at higher latitudes is controlled by sea surface temperature/productivity: for the modern and the Holocene, several ichnodiversity peaks match with well-constrained conditions (substrate, salinity, thermal fronts). By contrast, this does not hold for the Pleistocene: dissimilar conditions probably prevailed, especially during the Last Interglacial (colder waters richer in nutrients). Fil: Richiano, Sebastián Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: Aguirre, Marina Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: Farinati, Ester Amanda. Universidad Nacional del Sur; Argentina Fil: Davies, Karen. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: Castellanos, Ignacio. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina

Published
2015

42. AVANCES DEL PROYECTO "DESARROLLO DE UNA TIENDA VIRTUAL EMPLEANDO WORDPRESS Y WOOCOMMERCE PARA UNA EMPRESA COMERCIALIZADORA" CASO SERVICIOS PROFESIONALES DE ENFERMERIA.

Author

Morcillo Presenda, Freddy Alberto, Corona Ferreira, Arturo, Flores Lázaro, Carlos Mario, Almeida Aguilar, María Alejandrina, García Alcocer, Julio Humberto, Chapus Castañeda, Gustavo Adolfo, and Montecino Castellanos, Ignacio Antonio

Abstract

Copyright of Congreso Internacional de Investigacion Academia Journals is the property of PDHTech, LLC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2018

47. Aplicación informática de modelización del comportamiento de un motor, mediante la utilización de Redes Neuronales Artificiales (RNA)

Author

Santolaria Castellanos, Ignacio, Universitat Politècnica de Catalunya. Departament de Màquines i Motors Tèrmics, and Álvarez Flórez, Jesús Andrés

Subjects
Neural networks (Computer science), Matemàtiques i estadística::Investigació operativa::Simulació [Àrees temàtiques de la UPC], Termodinàmica -- Mètodes de simulació, Xarxes neuronals (Informàtica), Informàtica::Intel·ligència artificial [Àrees temàtiques de la UPC], Internal combustion engines, Enginyeria mecànica::Motors::Motors de combustió interna [Àrees temàtiques de la UPC], Thermodynamics -- Simulation methods, Motors de combustió interna
Abstract

El presente proyecto tiene como objetivo desarrollar un modelo de cálculo y control basado en una simulación termodinámica cero-dimensional de la fase cerrada – compresión, combustión y expansión de la mezcla aire-combustible – de un motor alternativo de combustión interna (MACI) de ciclo Otto. En primer lugar el estudio se centra en las redes neuronales, en sus diferentes tipologías y algoritmos de convergencia. Dicho modelo tiene en cuenta los principales parámetros que influyen en las diferentes etapas de la fase cerrada del ciclo termodinámico, tanto los mecánicos como los relacionados con el fluido motor. El actual proyecto desarrolla una aplicación informática partiendo del modelo final encontrado, programada con Matlab. El resultado de esta programación se visualizará mediante una guide también programada con Matlab. Esta aplicación permitirá de forma fácil y rápida visualizar datos, gráficos y resultados que podrán ser utilizados tanto en cursos de Termodinámica y Motores Térmicos como en la industria automovilística. También se presentará un manual de instrucciones de la aplicación programada para facilitar su comprensión y funcionamiento. Una aplicación práctica para el presente proyecto son los bancos de ensayos y pruebas de los motores. Los bancos de ensayos para motores son de vital importancia para el desarrollo de éstos (o el de alguno de sus componentes) ya que permiten tener un registro de su comportamiento tanto en las condiciones normales de funcionamiento como en situaciones extremas a las que puedan verse obligados a trabajar. El gran problema que presentan dichos bancos es su elevado coste económico. Este proyecto permitirá a partir de una serie de datos obtenidos con motores reales ahorrar un gran porcentaje en la inversión inicial del coste total de las diferentes pruebas de motores. Finalmente, se realizará un estudio económico sobre los costos que genera la instalación y puesta en marcha del presente proyecto.

Published
2010

50. ARTIFICIAL NEST PREDATION IN HEDGEROWS OF AN AGRO-URBAN SYSTEM IN HIDALGO, MEXICO

Author

Cervantes-Cornihs, Elizabeth, Zuria, Iriana, and Castellanos, Ignacio

Subjects
Ave, Trampa Ecológica, Agricultura, Escala del Paisaje, Escala Local
Abstract

En muchos agroecosistemas de América Latina las cercas vivas representan un hábitat importante para muchas especies de aves; sin embargo, aún no se conocen cuáles son las características de las cercas vivas y del paisaje circundante que influyen sobre la depredación de nidos en estas estructuras. Utilizando nidos artificiales, se estudió la depredación en 20 cercas vivas de un sistema agro-urbano del centro de México. Los datos de depredación de nidos se relacionaron con variables del hábitat a dos escalas espaciales, local y del paisaje. De los 200 nidos colocados 80 fueron depredados, y no se encontró ninguna relación significativa entre la depredación total y las variables a escala local. A escala del paisaje se observó que la depredación total aumentó en cercas vivas localizadas cerca de áreas cubiertas con vegetación nativa. Se encontró también que los principales depredadores fueron aves, seguidas de carnívoros y roedores. In many agro-ecosystems of Latin America, hedgerows are an important habitat for numerous bird species. However, the hedgerow characteristics and those of the surrounding landscape affecting nest predation in these structures are not known. Using artificial nests, predation was studied in 20 hedgerows located in an agro-urban system in central Mexico. Predation data was related with habitat variables at two spatial scales, local and landscape. Out of a total of 200 artificial nests put in place, 80 nests were predated and no significant relationship was found between total predation and local scale variables. At the landscape scale, total predation increased in hedgerows located near remnants of native vegetation. It was also found that birds were the main predators in this landscape, followed by carnivores and rodents.

Published
2009

Catalog

Books, media, physical & digital resources
See catalog results