Papers by Maria Esther Lescano
Universitas Psychologica, 2012
Los objetivos del presente artículo son describir el sistema de justicia juvenil en la provincia ... more Los objetivos del presente artículo son describir el sistema de justicia juvenil en la provincia de Buenos Aires (Argentina) desde las perspectivas jurídica y ejecutiva, y comunicar avances científicos globales en la evaluación de los jóvenes que cometen actos disociales. En la provincia de Buenos Aires el sistema ha sido profundamente modificado en los últimos 15 años siguiendo las premisas de la Convención Internacional sobre los Derechos del Niño y dejando relegado el modelo del Patronato, que había regido previamente. Las instituciones encargadas de la ejecución de la intervención dispuesta por el Poder Judicial dependen actualmente de la Subsecretaria de Niñez y Adolescencia del Ministerio de Desarrollo Social y constan de centros cerrados, centros con régimen de semilibertad y centros de intervención ambulatoria (medidas alternativas a la prisión, tales como suspensión de juicio a prueba o tareas comunitarias). Las ciencias relacionadas con la salud mental y con el comportamie...
Insectes Sociaux, 2015
Your article is protected by copyright and all rights are held exclusively by International Union... more Your article is protected by copyright and all rights are held exclusively by International Union for the Study of Social Insects (IUSSI). This e-offprint is for personal use only and shall not be self-archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".
Proceedings of the Royal Society B: Biological Sciences, 2012
Soil disturbances that increase nutrient availability may trigger bottom-up cascading effects alo... more Soil disturbances that increase nutrient availability may trigger bottom-up cascading effects along trophic chains. However, the strength and sign of these effects may depend on attributes of the interacting species. Here, we studied the effects of nutrient-rich refuse dumps of the leaf-cutting ant, Acromyrmex lobicornis , on the food chain composed of thistles, aphids, tending ants and aphid natural enemies. Using stable isotopes tracers, we show that the nitrogen accumulated in refuse dumps propagates upward through the studied food chain. Thistles growing on refuse dumps had greater biomass and higher aphid density than those growing in adjacent soil. These modifications did not affect the structure of the tending ant assemblage, but were associated with increased ant activity. In contrast to the expectations under the typical bottom-up cascade effect, the increase in aphid abundance did not positively impact on aphid natural enemies. This pattern may be explained by both an incr...
Universitas Psychologica, 2012
Los objetivos del presente artículo son describir el sistema de justicia juvenil en la provincia ... more Los objetivos del presente artículo son describir el sistema de justicia juvenil en la provincia de Buenos Aires (Argentina) desde las perspectivas jurídica y ejecutiva, y comunicar avances científicos globales en la evaluación de los jóvenes que cometen actos disociales. En la provincia de Buenos Aires el sistema ha sido profundamente modificado en los últimos 15 años siguiendo las premisas de la Convención Internacional sobre los Derechos del Niño y dejando relegado el modelo del Patronato, que había regido previamente. Las instituciones encargadas de la ejecución de la intervención dispuesta por el Poder Judicial dependen actualmente de la Subsecretaria de Niñez y Adolescencia del Ministerio de Desarrollo Social y constan de centros cerrados, centros con régimen de semilibertad y centros de intervención ambulatoria (medidas alternativas a la prisión, tales como suspensión de juicio a prueba o tareas comunitarias). Las ciencias relacionadas con la salud mental y con el comportamie...
Insectes Sociaux, 2015
Your article is protected by copyright and all rights are held exclusively by International Union... more Your article is protected by copyright and all rights are held exclusively by International Union for the Study of Social Insects (IUSSI). This e-offprint is for personal use only and shall not be self-archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".
Proceedings of the Royal Society B: Biological Sciences, 2012
Soil disturbances that increase nutrient availability may trigger bottom-up cascading effects alo... more Soil disturbances that increase nutrient availability may trigger bottom-up cascading effects along trophic chains. However, the strength and sign of these effects may depend on attributes of the interacting species. Here, we studied the effects of nutrient-rich refuse dumps of the leaf-cutting ant, Acromyrmex lobicornis , on the food chain composed of thistles, aphids, tending ants and aphid natural enemies. Using stable isotopes tracers, we show that the nitrogen accumulated in refuse dumps propagates upward through the studied food chain. Thistles growing on refuse dumps had greater biomass and higher aphid density than those growing in adjacent soil. These modifications did not affect the structure of the tending ant assemblage, but were associated with increased ant activity. In contrast to the expectations under the typical bottom-up cascade effect, the increase in aphid abundance did not positively impact on aphid natural enemies. This pattern may be explained by both an incr...
Polar Biology, 2010
Octacnemids represent a different pathway in the evolution of the typical filter-feeding ascidian... more Octacnemids represent a different pathway in the evolution of the typical filter-feeding ascidians. We examine and identify the prey items in the gut contents and describe the cell types that constitute the inner wall of different sections of the gut of the macrophagous octacnemid Cibacapsa gulosa collected in the South Sandwich Islands, Antarctica. A great variety of prey items were found: polychaetes, copepods, halacarids, amphipods, isopods and ophiuroids. The internal wall of the gut is lined with a monostratified, prismatic epithelium. Different cell types occur in the inner wall in different sections. The presence of zymogenic cells throughout the internal gut epithelium, as well as the presence of concretion cells in the stomach of C. gulosa, also present in the macrophagous tunicate group Sorberacea (= Hexacrobylidae), can be considered as an adaptation to the macrophagous diet.
Polar Biology, 2010
Octacnemids represent a different pathway in the evolution of the typical filter-feeding ascidian... more Octacnemids represent a different pathway in the evolution of the typical filter-feeding ascidians. We examine and identify the prey items in the gut contents and describe the cell types that constitute the inner wall of different sections of the gut of the macrophagous octacnemid Cibacapsa gulosa collected in the South Sandwich Islands, Antarctica. A great variety of prey items were found: polychaetes, copepods, halacarids, amphipods, isopods and ophiuroids. The internal wall of the gut is lined with a monostratified, prismatic epithelium. Different cell types occur in the inner wall in different sections. The presence of zymogenic cells throughout the internal gut epithelium, as well as the presence of concretion cells in the stomach of C. gulosa, also present in the macrophagous tunicate group Sorberacea (= Hexacrobylidae), can be considered as an adaptation to the macrophagous diet.
Ecological Research, 2011
Exotic species change the structure and composition of invaded communities in multiple ways, but ... more Exotic species change the structure and composition of invaded communities in multiple ways, but the sign of their impact on native species is still controversial. We evaluated the effects of the thistles Carduus thoermeri and Onopordum acanthium-two of the most abundant exotic plant species in disturbed areas of the Patagonian steppe-on the native tending ant assemblage. Exotic thistles showed an increased number of plants with aphids and had greater aphid density than native plants. Since native tending ants were present only in plants with aphids, their abundance was higher in infested thistles than in native plants. Path analyses confirmed that ant activity depended more on aphid density than on thistle traits. Our results suggest that the presence of exotic thistles in disturbed areas of NW Patagonia indirectly benefit the native ant assemblage through the maintenance of an increased aphid population. This illustrates how the impact of exotic on native species can depend on the ecological context.
Ecological Entomology, 2013
1. Interspecific competition plays a key role in the organisation of ant communities. In ant-plan... more 1. Interspecific competition plays a key role in the organisation of ant communities. In ant-plant interactions, individual host plants are usually occupied by a single ant colony, and co-occurring ant species compete for hosts. Here indirect evidence of competition between three dominant ant species that tend aphids on two biennial thistles in northern Patagonia is described, and a novel defensive behaviour in temperate ant assemblages is reported. 2. This study has found that: (i) dominant ant species were not spatially segregated, thus enhancing the probability of fights and invasions of host plants; (ii) ant species did not show preferences for a thistle species or for any plant characteristic, and thus all plants have similar chances of being colonised by all dominant ant species; (iii) the resident ant species remained on the same plant during the whole plant life cycle, monopolising plant resources (aphids); and (iv) all dominant species, whose nests are on the ground, assigned some ants to stay on the host plant during the night, when the low temperatures typical of this temperate environment greatly reduce foraging activities. When these 'nocturnal guards' were experimentally removed from the host plant, other ants from the same colony rapidly appeared showing aggressive behaviours. 3. Taking all these findings together, it is suggested that interspecific competition influences the distribution of ants on their host plants and involves nocturnal defensive behaviours despite unfavourable thermal conditions. This illustrates how habitat features, such as the short life cycle of thistles and the low night-time temperatures that reduce ant foraging and thus make plants more vulnerable to invasion, might affect the distribution and behaviour of ants.
Ninos Menores E Infancias, Dec 1, 2013
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Papers by Maria Esther Lescano