Convergence analysis of the scaled boundary finite element method for the Laplace equation

The scaled boundary finite element method (SBFEM) is a relatively recent boundary element method that allows the approximation of solutions to PDEs without the need of a fundamental solution. A theoretical framework for the convergence analysis of SBFEM is proposed here. This is achieved by defining a space of semi-discrete functions and constructing an interpolation operator onto this space. We prove error estimates for this interpolation operator and show that optimal convergence to the solution can be obtained in SBFEM. These theoretical results are backed by a numerical example.Comment: 15 pages, 3 figure

Aves de rapina diurnas em Llanos de Moxos, Bolívia

Raptor abundance has been poorly documented in the Neotropics. Here we describe the abundance and composition of the diurnal bird raptor community of Llanos de Moxos, one of the largest and less studied Neotropical savannah. During four consecutive breeding seasons (i.e., August 2007 to February 2008, August 2008 to January 2009, August 2009 to January 2010, and August 2010 to January 2011), we monitored 11 transects and 30 points, searching for raptors’ activity. We detected 29 diurnal bird raptor species in the region, which represented almost half of diurnal bird raptor species of Bolivia. As expected, scavengers and generalists were most frequent and abundant diurnal bird raptors. The Llanos de Moxos shared 83% of raptor species with Venezuelan Llanos and 67% with Chaco wetlands. The Llanos de Moxos is an important migratory and conservation region for some species as Swainson’s hawk, Chaco eagle, osprey and peregrine falcon. The lack of effective protected areas in the region is concerning, and, thus, the establishment of such areas should be a conservation priority.A abundância de aves de rapina tem sido pouco documentada na região Neotropical. No presente trabalho, descrevem-se a abundância e a composição da comunidade diurna de aves de rapina de Llanos de Moxos, uma das maiores e menos estudadas savanas neotropicais. Durante quatro períodos de reprodução consecutivos (agosto de 2007 a fevereiro de 2008, agosto de 2008 a janeiro de 2009, agosto de 2009 a janeiro de 2010 e agosto de 2010 a janeiro de 2011), foram monitorados 11 transectos e 30 pontos, buscando atividades de aves de rapina. Detectamos 29 espécies de aves de rapina diurnas na região, que representaram quase metade das espécies dessas aves diurnas da Bolívia. Como esperado, os detritívoros e generalistas foram as aves de rapina diurnas mais frequentes e abundantes. Os Llanos de Moxos compartilharam 83% de espécies de aves de rapina com Llanos venezuelanos e 67% com áreas úmidas de Chaco. Os Llanos de Moxos representam uma importante região migratória e de conservação para algumas espécies, tais como o falcão de Swainson, a águia cinzenta, a água pescadora e o falcão peregrino. A falta de áreas protegidas efetivas na região é preocupante, de forma que o estabelecimento de tais áreas deve ser considerado uma prioridade de conservação.Fil: Daniele, Gonzalo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico Zoología Vertebrados; ArgentinaFil: Kacoliris, Federico Pablo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología de Vertebrados. Sección Herpetología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Berkunsky, Igor. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Records of the Crowned Eagle (Urubitinga coronata) in Moxos plains of Bolivia and observations about breeding behavior

The Crowned Eagle (Urubitinga coronata, Accipitridae) is a globally endangered raptor, endemic to central and southern South America. Little is known about this species in Bolivia and no nesting or prey data have been reported for the country until now. Between 2007 and 2011, we detected Crowned Eagles in four different locations in Moxos Savannahs of Beni Department, Bolivia. We observed an active nest of Crowned Eagle on 23 November 2007. The nest contained a nestling and it was placed on a living tree approximately 13 m in height and approximately 8 m above the ground. This nest was empty during September and October 2008, but contained another nestling on 15 November 2009. These represent the first breeding records for the Crowned Eagle in Bolivia. Prey remains at the nest observed included two nine-banded armadillos (Dasypus novemcinctus) and two six-banded armadillos (Euphractus sexcinctus). The minimum number of individual Crowned Eagles in the surveyed area was seven. Our observations of family groups, juveniles and two nestlings confirm the breeding of Crowned Eagles in the Moxos plains. Ectoparasites and uncontrolled burns may threaten the northwestern Bolivian population of the endangered Crowned Eagle.Fil: Berkunsky, Igor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario sobre Ecosistemas y Desarrollo Sustentable. Grupo de Ecología Matemática; Argentina. Proyecto de conservación de la Paraba Barba Azul; BoliviaFil: Daniele, Gonzalo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina. Proyecto de conservación de la Paraba Barba Azul; BoliviaFil: Kacoliris, Federico Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina. Proyecto de conservación de la Paraba Barba Azul; BoliviaFil: Faegre, Sarah Kelly. University of Washington; Estados UnidosFil: Gandoy, Facundo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: González, Lyliam. Paraíso Travel; BoliviaFil: Díaz Luque, José Antonio. Proyecto de conservación de la Paraba Barba Azul; Bolivi

Annual diet of the little hairy armadillo, Chaetophractus vellerosus (Mammalia, Dasypodidae), in Buenos Aires Province, Argentina

Analysis of the stomach contents of 28 little hairy armadillos (Chaetophractus vellerosus), collected during a 14-month period at Pipinas, Argentina, showed that about 63.6% of the weight of prey items was composed of animal remains, 18% was plant material, and the remaining 18.4% was undetermined organic remains. Insects were the most frequent diet item, followed by plant material, amphibians, reptiles, and lastly birds and mammals in similar proportion. During autumn, plant material was the most abundant item, followed by vertebrates and invertebrates. During winter invertebrates prevailed, followed by a lower percentage of vertebrates and scarce plant remains. Invertebrates also were predominant during spring, whereas plant material and vertebrates composed very low percentages.Facultad de Ciencias Naturales y MuseoCentro de Estudios Parasitológicos y de Vectore

Annual diet of the little hairy armadillo, Chaetophractus vellerosus (Mammalia, Dasypodidae), in Buenos Aires Province, Argentina

Analysis of the stomach contents of 28 little hairy armadillos (Chaetophractus vellerosus), collected during a 14-month period at Pipinas, Argentina, showed that about 63.6% of the weight of prey items was composed of animal remains, 18% was plant material, and the remaining 18.4% was undetermined organic remains. Insects were the most frequent diet item, followed by plant material, amphibians, reptiles, and lastly birds and mammals in similar proportion. During autumn, plant material was the most abundant item, followed by vertebrates and invertebrates. During winter invertebrates prevailed, followed by a lower percentage of vertebrates and scarce plant remains. Invertebrates also were predominant during spring, whereas plant material and vertebrates composed very low percentages.Facultad de Ciencias Naturales y MuseoCentro de Estudios Parasitológicos y de Vectore

Aves de rapina diurnas em Llanos de Moxos, Bolívia

Raptor abundance has been poorly documented in the Neotropics. Here we describe the abundance and composition of the diurnal bird raptor community of Llanos de Moxos, one of the largest and less studied Neotropical savannah. During four consecutive breeding seasons (i.e., August 2007 to February 2008, August 2008 to January 2009, August 2009 to January 2010, and August 2010 to January 2011), we monitored 11 transects and 30 points, searching for raptors’ activity. We detected 29 diurnal bird raptor species in the region, which represented almost half of diurnal bird raptor species of Bolivia. As expected, scavengers and generalists were most frequent and abundant diurnal bird raptors. The Llanos de Moxos shared 83% of raptor species with Venezuelan Llanos and 67% with Chaco wetlands. The Llanos de Moxos is an important migratory and conservation region for some species as Swainson’s hawk, Chaco eagle, osprey and peregrine falcon. The lack of effective protected areas in the region is concerning, and, thus, the establishment of such areas should be a conservation priority.A abundância de aves de rapina tem sido pouco documentada na região Neotropical. No presente trabalho, descrevem-se a abundância e a composição da comunidade diurna de aves de rapina de Llanos de Moxos, uma das maiores e menos estudadas savanas neotropicais. Durante quatro períodos de reprodução consecutivos (agosto de 2007 a fevereiro de 2008, agosto de 2008 a janeiro de 2009, agosto de 2009 a janeiro de 2010 e agosto de 2010 a janeiro de 2011), foram monitorados 11 transectos e 30 pontos, buscando atividades de aves de rapina. Detectamos 29 espécies de aves de rapina diurnas na região, que representaram quase metade das espécies dessas aves diurnas da Bolívia. Como esperado, os detritívoros e generalistas foram as aves de rapina diurnas mais frequentes e abundantes. Os Llanos de Moxos compartilharam 83% de espécies de aves de rapina com Llanos venezuelanos e 67% com áreas úmidas de Chaco. Os Llanos de Moxos representam uma importante região migratória e de conservação para algumas espécies, tais como o falcão de Swainson, a águia cinzenta, a água pescadora e o falcão peregrino. A falta de áreas protegidas efetivas na região é preocupante, de forma que o estabelecimento de tais áreas deve ser considerado uma prioridade de conservação.Facultad de Ciencias Naturales y Muse

Aplicación de herramientas CASE a la enseñanza de ingeniería de software: gestión de la configuración de software y testing funcional

La Ingeniería de Software (IS) es la disciplina o área de la informática que ofrece métodos y técnicas para el desarrollo y mantenimiento de software de calidad. A pesar de todos los esfuerzos realizados, en las sucesivas etapas del desarrollo y en las actividades de gestión de proyectos de software, ocurren problemas como: carencia de fiabilidad, necesidad de mantenimiento permanente, etc. Las dinámicas de los procesos de desarrollo de software exigen una actualización constante de técnicas y tecnologías. Esta tarea es favorecida por la utilización de herramientas CASE que asisten a todos los involucrados en la construcción del software. En el siguiente trabajo se presenta una propuesta de enseñanza de algunos tópicos fundamentales de la IS como son: Gestión de la configuración del Software (GCS) y Testing. El trabajo muestra los resultados obtenidos con la ejecución de dos Proyectos- Taller, en los temas mencionados. Se propone un aporte a la enseñanza de la IS, capacitando a los alumnos en el uso de técnicas y herramientas. Se busca generar en los estudiantes los mecanismos adecuados para profundizar la comprensión de los temas de GCS y Testing.Red de Universidades con Carreras en Informática (RedUNCI

Air-core fiber distribution of hybrid vector vortex-polarization entangled states

Entanglement distribution between distant parties is one of the most important and challenging tasks in quantum communication. Distribution of photonic entangled states using optical fiber links is a fundamental building block towards quantum networks. Among the different degrees of freedom, orbital angular momentum (OAM) is one of the most promising due to its natural capability to encode high dimensional quantum states. In this article, we experimentally demonstrate fiber distribution of hybrid polarization-vector vortex entangled photon pairs. To this end, we exploit a recently developed air-core fiber which supports OAM modes. High fidelity distribution of the entangled states is demonstrated by performing quantum state tomography in the polarization-OAM Hilbert space after fiber propagation, and by violations of Bell inequalities and multipartite entanglement tests. The present results open new scenarios for quantum applications where correlated complex states can be transmitted by exploiting the vectorial nature of light

Records of the crowned eagle (<i>Urubitinga coronata</i>) in Moxos plains of Bolivia and observations about breeding behavior

The Crowned Eagle (Urubitinga coronata, Accipitridae) is a globally endangered raptor, endemic to central and southern South America. Little is known about this species in Bolivia and no nesting or prey data have been reported for the country until now. Between 2007 and 2011, we detected Crowned Eagles in four different locations in Moxos Savannahs of Beni Department, Bolivia. We observed an active nest of Crowned Eagle on 23 November 2007. The nest contained a nestling and it was placed on a living tree approximately 13 m in height and approximately 8 m above the ground. This nest was empty during September and October 2008, but contained another nestling on 15 November 2009. These represent the first breeding records for the Crowned Eagle in Bolivia. Prey remains at the nest observed included two nine-banded armadillos (Dasypus novemcinctus) and two six-banded armadillos (Euphractus sexcinctus). The minimum number of individual Crowned Eagles in the surveyed area was seven. Our observations of family groups, juveniles and two nestlings confirm the breeding of Crowned Eagles in the Moxos plains. Ectoparasites and uncontrolled burns may threaten the northwestern Bolivian population of the endangered Crowned Eagle.Facultad de Ciencias Naturales y Muse

Records of the crowned eagle (<i>Urubitinga coronata</i>) in Moxos plains of Bolivia and observations about breeding behavior

The Crowned Eagle (Urubitinga coronata, Accipitridae) is a globally endangered raptor, endemic to central and southern South America. Little is known about this species in Bolivia and no nesting or prey data have been reported for the country until now. Between 2007 and 2011, we detected Crowned Eagles in four different locations in Moxos Savannahs of Beni Department, Bolivia. We observed an active nest of Crowned Eagle on 23 November 2007. The nest contained a nestling and it was placed on a living tree approximately 13 m in height and approximately 8 m above the ground. This nest was empty during September and October 2008, but contained another nestling on 15 November 2009. These represent the first breeding records for the Crowned Eagle in Bolivia. Prey remains at the nest observed included two nine-banded armadillos (Dasypus novemcinctus) and two six-banded armadillos (Euphractus sexcinctus). The minimum number of individual Crowned Eagles in the surveyed area was seven. Our observations of family groups, juveniles and two nestlings confirm the breeding of Crowned Eagles in the Moxos plains. Ectoparasites and uncontrolled burns may threaten the northwestern Bolivian population of the endangered Crowned Eagle.Facultad de Ciencias Naturales y Muse