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Search Results: 1 - 10 of 24279 matches for " Paul Hanson "
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Fifty years of entomological publications in the Revista de Biología Tropical
Hanson,Paul;
Revista de Biología Tropical , 2002,
Abstract: over its fifty year history nearly twenty percent of the papers published in the revista de biología tropical have been about inseets and arachnids. in the 1950's papers on arthropods of medical importance were dominant, in the 1960's there was a poliferation of papers on bees, and in more recent years the subjects have become incresingly diverse. in terms of nationality of contributing authors, the journal appears to have become increasingly international in later years.
Fifty years of entomological publications in the Revista de Biología Tropical
Paul Hanson
Revista de Biología Tropical , 2002,
Abstract: Over its fifty year history nearly twenty percent of the papers published in the Revista de Biología Tropical have been about inseets and arachnids. In the 1950's papers on arthropods of medical importance were dominant, in the 1960's there was a poliferation of papers on bees, and in more recent years the subjects have become incresingly diverse. In terms of nationality of contributing authors, the journal appears to have become increasingly international in later years. A través de su historia de cincuenta a os, casi veinte porciento de los artículos publicados en la Revista de Biología Tropical trataron de insectos y arácnidos. En los aiíos cincuenta dominaron los artículos sobre artrópodos de importancia médica, en los a os sesenta hubo una proliferación de artículos sobre abejas, y en los últimos a os los temas incluidos se hicieron más diversos. En términos de la nacionalidad de los autores contribuyentes, parece que la revista se ha vuelto más internacional en los últimos a os.
A Systematic Approach to Selecting Inexpensive Conservation Storage Solutions
Paul Garside,Lesley Hanson
Journal of Conservation and Museum Studies , 2011, DOI: 10.5334/jcms.91102
Abstract: The appropriate storage of heritage artefacts is vital to their long-term survival, but selecting suitable storage solutions is not always easy due to the number of potentially conflicting factors that must be considered: the method of housing should be compatible with both the objects themselves and with the local environment; it must offer adequate support and protection; it should ideally be inexpensive, readily available and easy to use. Following the discovery of objects in the British Library’s collection which were showing initial signs of damage due to inappropriate storage, a systematic approach to selecting and assessing potential housing solutions was devised, as reported herein. A particular aim was to use containers, materials and testing regimes that could be sourced easily and affordably, thus permitting the rapid rehousing of all of the items identified as being at risk. This emphasis also places such test protocols and storage solutions within the reach of smaller collections with limited budgets and resources.
A fly larva (Syrphidae: Ocyptamus) that preys on adult flies
Ure?a,Onanchi; Hanson,Paul;
Revista de Biología Tropical , 2010,
Abstract: predatory syrphid larvae feed on relatively immobile prey, but here we report the first case (as far as we are aware) of obligatory predation on very mobile prey. larvae of an undescribed species of ocyptamus (diptera: syrphidae) were found in whitefly (hemiptera: aleyrodidae) aggregations on the undersides of citrus leaves. however, instead of preying on the whitefly nymphs (as would be expected), the larvae preyed on adult flies (diptera) that were attracted to the honeydew. in the laboratory, larvae captured significantly more flies on whitefly infested leaves than on washed leaves, and generally abandoned leaves that lacked whiteflies. most cases of successful prey capture involved flies that probed the anterior part of the larva’s body with its proboscis (as if it were honeydew). the syrphid larva lashed out at the fly and entangled it in sticky oral secretion. the prey did not recover when they were removed from the larva, suggesting that this new predatory species also employs venom to subdue its prey. although the larvae consumed some honeydew, they were unable to complete their development on this diet. two parasitoids were reared from ocyptamus puparia, proaspicera sp. (hymenoptera: figitidae) and paracarotomus sp. (hymenoptera: pteromalidae), both of which are endoparasitic koinobionts. rev. biol. trop. 58 (4): 1157-1163. epub 2010 december 01.
A fly larva (Syrphidae: Ocyptamus) that preys on adult flies
Onanchi Ure?a,Paul Hanson
Revista de Biología Tropical , 2010,
Abstract: Predatory syrphid larvae feed on relatively immobile prey, but here we report the first case (as far as we are aware) of obligatory predation on very mobile prey. Larvae of an undescribed species of Ocyptamus (Diptera: Syrphidae) were found in whitefly (Hemiptera: Aleyrodidae) aggregations on the undersides of citrus leaves. However, instead of preying on the whitefly nymphs (as would be expected), the larvae preyed on adult flies (Diptera) that were attracted to the honeydew. In the laboratory, larvae captured significantly more flies on whitefly infested leaves than on washed leaves, and generally abandoned leaves that lacked whiteflies. Most cases of successful prey capture involved flies that probed the anterior part of the larva’s body with its proboscis (as if it were honeydew). The syrphid larva lashed out at the fly and entangled it in sticky oral secretion. The prey did not recover when they were removed from the larva, suggesting that this new predatory species also employs venom to subdue its prey. Although the larvae consumed some honeydew, they were unable to complete their development on this diet. Two parasitoids were reared from Ocyptamus puparia, Proaspicera sp. (Hymenoptera: Figitidae) and Paracarotomus sp. (Hymenoptera: Pteromalidae), both of which are endoparasitic koinobionts. Rev. Biol. Trop. 58 (4): 1157-1163. Epub 2010 December 01. Las larvas depredadoras de Syrphidae se alimentan de presas relativamente inmóviles, pero aquí reportamos el primer caso (hasta ahora conocido) de la depredación obligatoria en presas muy móviles. Se encontraron las larvas de una especie no descrita de Ocyptamus (Diptera: Syrphidae) juntas con ninfas de mosca blanca (Hemiptera: Aleyrodidae) en el envés de las hojas de cítricos. Sin embargo, en vez de alimentarse de las ninfas de mosca blanca (como debería esperarse), las larvas se alimentaron de moscas adultas (Diptera) que fueron atraídas a las excreciones azucaradas de la mosca blanca. En el laboratorio, las larvas capturaron más moscas cuando estaban en hojas con mosca blanca que cuando estaban en hojas lavadas, y generalmente abandonaron las hojas sin mosca blanca. La mayoría de las capturas exitosas de presas ocurrieron cuando la mosca extendió su proboscis y tocó la parte anterior de la larva del sírfido. La larva regurgita hilos pegajosos en el momento de capturar una presa y presas removidas de la larva no recuperaron su movibilidad, lo cual sugiere que el depredador utiliza un veneno para inmovilizar la presa. Aunque las larvas se alimentaron de excreciones azucaradas de mosca blanca, no pudie
Ecological and Social Dynamics in Simple Models of Ecosystem Management
Stephen R. Carpenter,William Brock,Paul Hanson
Ecology and Society , 1999,
Abstract: Simulation models were developed to explore and illustrate dynamics of socioecological systems. The ecosystem is a lake subject to phosphorus pollution. Phosphorus flows from agriculture to upland soils, to surface waters, where it cycles between water and sediments. The ecosystem is multistable, and moves among domains of attraction depending on the history of pollutant inputs. The alternative states yield different economic benefits. Agents form expectations about ecosystem dynamics, markets, and/or the actions of managers, and choose levels of pollutant inputs accordingly. Agents have heterogeneous beliefs and/or access to information. Their aggregate behavior determines the total rate of pollutant input. As the ecosystem changes, agents update their beliefs and expectations about the world they co-create, and modify their actions accordingly. For a wide range of scenarios, we observe irregular oscillations among ecosystem states and patterns of agent behavior. These oscillations resemble some features of the adaptive cycle of panarchy theory.
Capítulo 1: Introducción a los grupos de macroinvertebrados acuáticos
Paul Hanson,Monika Springer,Alonso Ramirez
Revista de Biología Tropical , 2010,
Abstract:
Multiple Scattering of Seismic Waves from Ensembles of Upwardly Lossy Thin Flux Tubes
Chris S. Hanson,Paul S. Cally
Physics , 2015, DOI: 10.1007/s11207-015-0732-x
Abstract: Our previous semi-analytic treatment of f- and p-mode multiple scattering from ensembles of thin flux tubes (Hanson and Cally, Astrophys. J. 781, 125; 791, 129, 2014) is extended by allowing both sausage and kink waves to freely escape at the top of the model using a radiative boundary condition there. As expected, this additional avenue of escape, supplementing downward loss into the deep solar interior, results in substantially greater absorption of incident f- and p-modes. However, less intuitively, it also yields mildly to substantially smaller phase shifts in waves emerging from the ensemble. This may have implications for the interpretation of seismic data for solar plage regions, and in particular their small measured phase shifts.
An Analytical Approach to Scattering Between Two Thin Magnetic Flux Tubes in a Stratified Atmosphere
Chris S. Hanson,Paul S. Cally
Physics , 2013, DOI: 10.1088/0004-637X/781/2/125
Abstract: We expand on recent studies to analytically model the behavior of two thin flux tubes interacting through the near- and acoustic far-field. The multiple scattering that occurs between the pair alters the absorption and phase of the outgoing wave, when compared to non-interacting tubes. We have included both the sausage and kink scatter produced by the pair. It is shown that the sausage mode's contribution to the scattered wave field is significant, and plays an equally important role in the multiple scattering regime. A disparity between recent numerical results and analytical studies, in particular the lack of symmetry between the two kink modes, is addressed. This symmetry break is found to be caused by an incorrect solution for the near-field modes.
The scattering of $f$- and $p$-modes from ensembles of thin magnetic flux tubes - An analytical approach
Chris S. Hanson,Paul S. Cally
Physics , 2014, DOI: 10.1088/0004-637X/791/2/129
Abstract: Motivated by the observational results of Braun (1995), we extend the model of Hanson & Cally (2014) to address the effect of multiple scattering of f and p-modes by an ensemble of thin vertical magnetic flux tubes in the surface layers of the Sun. As in observational Hankel analysis we measure the scatter and phase shift from an incident cylindrical wave in a coordinate system roughly centred in the core of the ensemble. It is demonstrated that, although thin flux tubes are unable to interact with high order fluting modes individually, they can indirectly absorb energy from these waves through the scatters of kink and sausage components. It is also shown how the distribution of absorption and phase shift across the azimuthal order m depends strongly on the tube position, as well as on the individual tube characteristics. This is the first analytical study into an ensembles multiple scattering regime, that is embedded within a strati?ed atmosphere.
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