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The humpback whale (Megatera novaengliae) is a cosmopolitan species of large whale that typically undertakes annual migrations between high latitude summer feeding areas and low latitude winter breeding and calving areas (Dawbin, 1966)...

The humpback whale (Megatera novaengliae) is a cosmopolitan species of large whale that typically undertakes annual migrations between high latitude summer feeding areas and low latitude winter breeding and calving areas (Dawbin, 1966)...

AIM: Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW). LOCATION: Global. TAXON: All extant mammal species. METHODS: Range maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species). RESULTS: Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use. MAIN CONCLUSION: Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control.

There is an extensive literature on the importance of the use of scientific evidence on teaching methods in higher education institutions. However, there is a gap in how evidence is used for decision making that affects students and staff in universities. This article is a contribution to the existing gap, making the analysis of a specific case on how Catalan universities have managed the decision making regarding their staff in the face of the pandemic situation with the COVID-19. In this article, through the interview with managers and faculty from different Catalan universities, it will be shown to what extent these university institutions have opted for decision making in the management of the situation based on scientific evidence or simply compliance with government regulations.

Research on gender violence has identified as one main component leading to gender violence a dominant socialization process which associates attractiveness to men who show violent behaviors and attitudes, while egalitarian and non-violent men are emptied of attractiveness. This is known as coercive dominant discourse. Starting from the evidence that the peer group is a main context of socialization in adolescence, quantitative data were collected from six classes of secondary education (14–15-year-old adolescents) to explore whether the coercive dominant discourse is displayed in social interactions in the peer group and, if so, how it influences attractiveness patterns and sexual-affective behavior in adolescence. The analyses reveal that the coercive dominant discourse is often reproduced in the peer group interactions, creating group pressure, and pushing some girls to violent relationships. Alternative ways of interaction are also reported, which allow a socialization leading to more freedom, less coercion, and more healthy relationships.

© Copyright © 2020 Duque, Gairal, Molina and Roca. One current challenge in the psychology of education is identifying the teaching strategies and learning contexts that best contribute to the learning of all students, especially those whose individual characteristics make their learning process more difficult, as is the case for students with special needs. One main theory in the psychology of education is the sociocultural approach to learning, which highlights the key role of interaction in children’s learning. In the case of students with disabilities, this interactive understanding of learning is aligned with a social model of disability, which looks beyond individual students’ limitations or potentialities and focuses on contextual aspects that can enhance their learning experience and results. In recent years, the interactive view of learning based on this theory has led to the development of educational actions, such as interactive groups and dialogic literary gatherings, that have improved the learning results of diverse children, including those with disabilities. The aim of this paper is to analyze the social impact achieved by a line of research that has explored the benefits of such successful educational actions for the education of students with special needs. National and European research projects based on the communicative methodology of research have been conducted. This methodology entails drawing on egalitarian dialogue with the end-users of research – including teachers, students with and without disabilities, students’ relatives and other community members – to allow an intersubjective creation of knowledge that enables a deeper and more accurate understanding of the studied reality and its transformative potential. This line of research first all

An efficient transport service allows a society to have economic progress and improves quality of life. Part of this structure is the issue in the determination of pricing the service of it, thus, the incomes of the offeror and good service to the user can be guaranteed. In Ecuador, the National Traffic Agency establishes a methodology that considers the offer of kilometers and operating costs. However, this methodology does not establish how to get and analyse the information that feeds the model, this aspect can generate biases and subjectivities at the time to define the rate. This study seeks to detect deficiencies in the methodology and suggest the relevant changes as an alternative to it, for this a mixed approach is considered, which not only considers surveys but also instrumentation and hi-technology to measure fuel consumption, tire wear, distance traveled and number of passengers. Once the analysis of the methodology was developed, a new approach to information gathering was proposed; and to validate, an experiment was applied to a canton of the country, with this it was possible to obtain rates that better represent the reality of the sector under analysis., Un eficiente servicio de transporte permite a una sociedad progreso económico y mejora calidad de vida. Parte de dicha planificación es la determinación de tarifas para servicio de taxi, pues así se puede garantizar la rentabilidad del oferente y un buen servicio al usuario. En Ecuador, la Agencia Nacional de Tránsito establece una metodología que considera la oferta de kilómetros y los costos de operación. Sin embargo, dicha metodología no establece cómo levantar la información que alimenta al modelo, pudiendo este vacío generar sesgos y subjetividades. Este estudio busca detectar deficiencias en la metodología, y sugerir los cambios pertinentes como alternativa a la misma, para ello se considera un enfoque mixto, que no solo considere encuestas sino también instrumentación y tecnología para medir consumo de combustible, desgaste de neumáticos, distancia recorrida y número de pasajeros. Desarrollado el análisis de la metodología se propuso un nuevo enfoque de levantamiento de información; y para validar el mismo se aplicó a un cantón del país, con ello se pudo obtener tarifas que representan de mejor manera la realidad del sector en análisis.

An efficient transport service allows a society to have economic progress and improves quality of life. Part of this structure is the issue in the determination of pricing the service of it, thus, the incomes of the offeror and good service to the user can be guaranteed. In Ecuador, the National Traffic Agency establishes a methodology that considers the offer of kilometers and operating costs. However, this methodology does not establish how to get and analyse the information that feeds the model, this aspect can generate biases and subjectivities at the time to define the rate. This study seeks to detect deficiencies in the methodology and suggest the relevant changes as an alternative to it, for this a mixed approach is considered, which not only considers surveys but also instrumentation and hi-technology to measure fuel consumption, tire wear, distance traveled and number of passengers. Once the analysis of the methodology was developed, a new approach to information gathering was proposed; and to validate, an experiment was applied to a canton of the country, with this it was possible to obtain rates that better represent the reality of the sector under analysis., Un eficiente servicio de transporte permite a una sociedad progreso económico y mejora calidad de vida. Parte de dicha planificación es la determinación de tarifas para servicio de taxi, pues así se puede garantizar la rentabilidad del oferente y un buen servicio al usuario. En Ecuador, la Agencia Nacional de Tránsito establece una metodología que considera la oferta de kilómetros y los costos de operación. Sin embargo, dicha metodología no establece cómo levantar la información que alimenta al modelo, pudiendo este vacío generar sesgos y subjetividades. Este estudio busca detectar deficiencias en la metodología, y sugerir los cambios pertinentes como alternativa a la misma, para ello se considera un enfoque mixto, que no solo considere encuestas sino también instrumentación y tecnología para medir consumo de combustible, desgaste de neumáticos, distancia recorrida y número de pasajeros. Desarrollado el análisis de la metodología se propuso un nuevo enfoque de levantamiento de información; y para validar el mismo se aplicó a un cantón del país, con ello se pudo obtener tarifas que representan de mejor manera la realidad del sector en análisis.

An efficient transport service allows a society to have economic progress and improves quality of life. Part of this structure is the issue in the determination of pricing the service of it, thus, the incomes of the offeror and good service to the user can be guaranteed. In Ecuador, the National Traffic Agency establishes a methodology that considers the offer of kilometers and operating costs. However, this methodology does not establish how to get and analyse the information that feeds the model, this aspect can generate biases and subjectivities at the time to define the rate. This study seeks to detect deficiencies in the methodology and suggest the relevant changes as an alternative to it, for this a mixed approach is considered, which not only considers surveys but also instrumentation and hi-technology to measure fuel consumption, tire wear, distance traveled and number of passengers. Once the analysis of the methodology was developed, a new approach to information gathering was proposed; and to validate, an experiment was applied to a canton of the country, with this it was possible to obtain rates that better represent the reality of the sector under analysis., Un eficiente servicio de transporte permite a una sociedad progreso económico y mejora calidad de vida. Parte de dicha planificación es la determinación de tarifas para servicio de taxi, pues así se puede garantizar la rentabilidad del oferente y un buen servicio al usuario. En Ecuador, la Agencia Nacional de Tránsito establece una metodología que considera la oferta de kilómetros y los costos de operación. Sin embargo, dicha metodología no establece cómo levantar la información que alimenta al modelo, pudiendo este vacío generar sesgos y subjetividades. Este estudio busca detectar deficiencias en la metodología, y sugerir los cambios pertinentes como alternativa a la misma, para ello se considera un enfoque mixto, que no solo considere encuestas sino también instrumentación y tecnología para medir consumo de combustible, desgaste de neumáticos, distancia recorrida y número de pasajeros. Desarrollado el análisis de la metodología se propuso un nuevo enfoque de levantamiento de información; y para validar el mismo se aplicó a un cantón del país, con ello se pudo obtener tarifas que representan de mejor manera la realidad del sector en análisis.

An efficient transport service allows a society to have economic progress and improves quality of life. Part of this structure is the issue in the determination of pricing the service of it, thus, the incomes of the offeror and good service to the user can be guaranteed. In Ecuador, the National Traffic Agency establishes a methodology that considers the offer of kilometers and operating costs. However, this methodology does not establish how to get and analyse the information that feeds the model, this aspect can generate biases and subjectivities at the time to define the rate. This study seeks to detect deficiencies in the methodology and suggest the relevant changes as an alternative to it, for this a mixed approach is considered, which not only considers surveys but also instrumentation and hi-technology to measure fuel consumption, tire wear, distance traveled and number of passengers. Once the analysis of the methodology was developed, a new approach to information gathering was proposed; and to validate, an experiment was applied to a canton of the country, with this it was possible to obtain rates that better represent the reality of the sector under analysis., Un eficiente servicio de transporte permite a una sociedad progreso económico y mejora calidad de vida. Parte de dicha planificación es la determinación de tarifas para servicio de taxi, pues así se puede garantizar la rentabilidad del oferente y un buen servicio al usuario. En Ecuador, la Agencia Nacional de Tránsito establece una metodología que considera la oferta de kilómetros y los costos de operación. Sin embargo, dicha metodología no establece cómo levantar la información que alimenta al modelo, pudiendo este vacío generar sesgos y subjetividades. Este estudio busca detectar deficiencias en la metodología, y sugerir los cambios pertinentes como alternativa a la misma, para ello se considera un enfoque mixto, que no solo considere encuestas sino también instrumentación y tecnología para medir consumo de combustible, desgaste de neumáticos, distancia recorrida y número de pasajeros. Desarrollado el análisis de la metodología se propuso un nuevo enfoque de levantamiento de información; y para validar el mismo se aplicó a un cantón del país, con ello se pudo obtener tarifas que representan de mejor manera la realidad del sector en análisis.

An efficient transport service allows a society to have economic progress and improves quality of life. Part of this structure is the issue in the determination of pricing the service of it, thus, the incomes of the offeror and good service to the user can be guaranteed. In Ecuador, the National Traffic Agency establishes a methodology that considers the offer of kilometers and operating costs. However, this methodology does not establish how to get and analyse the information that feeds the model, this aspect can generate biases and subjectivities at the time to define the rate. This study seeks to detect deficiencies in the methodology and suggest the relevant changes as an alternative to it, for this a mixed approach is considered, which not only considers surveys but also instrumentation and hi-technology to measure fuel consumption, tire wear, distance traveled and number of passengers. Once the analysis of the methodology was developed, a new approach to information gathering was proposed; and to validate, an experiment was applied to a canton of the country, with this it was possible to obtain rates that better represent the reality of the sector under analysis., Un eficiente servicio de transporte permite a una sociedad progreso económico y mejora calidad de vida. Parte de dicha planificación es la determinación de tarifas para servicio de taxi, pues así se puede garantizar la rentabilidad del oferente y un buen servicio al usuario. En Ecuador, la Agencia Nacional de Tránsito establece una metodología que considera la oferta de kilómetros y los costos de operación. Sin embargo, dicha metodología no establece cómo levantar la información que alimenta al modelo, pudiendo este vacío generar sesgos y subjetividades. Este estudio busca detectar deficiencias en la metodología, y sugerir los cambios pertinentes como alternativa a la misma, para ello se considera un enfoque mixto, que no solo considere encuestas sino también instrumentación y tecnología para medir consumo de combustible, desgaste de neumáticos, distancia recorrida y número de pasajeros. Desarrollado el análisis de la metodología se propuso un nuevo enfoque de levantamiento de información; y para validar el mismo se aplicó a un cantón del país, con ello se pudo obtener tarifas que representan de mejor manera la realidad del sector en análisis.

An efficient transport service allows a society to have economic progress and improves quality of life. Part of this structure is the issue in the determination of pricing the service of it, thus, the incomes of the offeror and good service to the user can be guaranteed. In Ecuador, the National Traffic Agency establishes a methodology that considers the offer of kilometers and operating costs. However, this methodology does not establish how to get and analyse the information that feeds the model, this aspect can generate biases and subjectivities at the time to define the rate. This study seeks to detect deficiencies in the methodology and suggest the relevant changes as an alternative to it, for this a mixed approach is considered, which not only considers surveys but also instrumentation and hi-technology to measure fuel consumption, tire wear, distance traveled and number of passengers. Once the analysis of the methodology was developed, a new approach to information gathering was proposed; and to validate, an experiment was applied to a canton of the country, with this it was possible to obtain rates that better represent the reality of the sector under analysis., Un eficiente servicio de transporte permite a una sociedad progreso económico y mejora calidad de vida. Parte de dicha planificación es la determinación de tarifas para servicio de taxi, pues así se puede garantizar la rentabilidad del oferente y un buen servicio al usuario. En Ecuador, la Agencia Nacional de Tránsito establece una metodología que considera la oferta de kilómetros y los costos de operación. Sin embargo, dicha metodología no establece cómo levantar la información que alimenta al modelo, pudiendo este vacío generar sesgos y subjetividades. Este estudio busca detectar deficiencias en la metodología, y sugerir los cambios pertinentes como alternativa a la misma, para ello se considera un enfoque mixto, que no solo considere encuestas sino también instrumentación y tecnología para medir consumo de combustible, desgaste de neumáticos, distancia recorrida y número de pasajeros. Desarrollado el análisis de la metodología se propuso un nuevo enfoque de levantamiento de información; y para validar el mismo se aplicó a un cantón del país, con ello se pudo obtener tarifas que representan de mejor manera la realidad del sector en análisis.

An efficient transport service allows a society to have economic progress and improves quality of life. Part of this structure is the issue in the determination of pricing the service of it, thus, the incomes of the offeror and good service to the user can be guaranteed. In Ecuador, the National Traffic Agency establishes a methodology that considers the offer of kilometers and operating costs. However, this methodology does not establish how to get and analyse the information that feeds the model, this aspect can generate biases and subjectivities at the time to define the rate. This study seeks to detect deficiencies in the methodology and suggest the relevant changes as an alternative to it, for this a mixed approach is considered, which not only considers surveys but also instrumentation and hi-technology to measure fuel consumption, tire wear, distance traveled and number of passengers. Once the analysis of the methodology was developed, a new approach to information gathering was proposed; and to validate, an experiment was applied to a canton of the country, with this it was possible to obtain rates that better represent the reality of the sector under analysis., Un eficiente servicio de transporte permite a una sociedad progreso económico y mejora calidad de vida. Parte de dicha planificación es la determinación de tarifas para servicio de taxi, pues así se puede garantizar la rentabilidad del oferente y un buen servicio al usuario. En Ecuador, la Agencia Nacional de Tránsito establece una metodología que considera la oferta de kilómetros y los costos de operación. Sin embargo, dicha metodología no establece cómo levantar la información que alimenta al modelo, pudiendo este vacío generar sesgos y subjetividades. Este estudio busca detectar deficiencias en la metodología, y sugerir los cambios pertinentes como alternativa a la misma, para ello se considera un enfoque mixto, que no solo considere encuestas sino también instrumentación y tecnología para medir consumo de combustible, desgaste de neumáticos, distancia recorrida y número de pasajeros. Desarrollado el análisis de la metodología se propuso un nuevo enfoque de levantamiento de información; y para validar el mismo se aplicó a un cantón del país, con ello se pudo obtener tarifas que representan de mejor manera la realidad del sector en análisis.

Non-human primates, our closest biological relatives, play important roles in the livelihoods, cultures and religions of many societies, and offer unique insights into human evolution, biology, behavior and the threat of emerging diseases. They are an essential component of tropical biodiversity, contributing to forest regeneration and ecosystem health. The most recent compilation of primate taxonomy lists 504 species, 197 subspecies and 79 genera distributed in the Neotropics, mainland Africa, Madagascar and Asia. Alarmingly, ~60% of primate species are now threatened with extinction as a result of unsustainable human activities, including illegal hunting and those resulting in extensive land-cover changes: industry driven agricultural production, deforestation, livestock and cattle ranching, oil and gas drilling, mining, dam building, climate change, and poor governance. Although drivers of primate decline vary by region, it is clear that decreasing the per capita demand of industrialized nations, lowering human birth rates and population growth, improving health, reducing poverty and gender biases in education, developing sustainable land-use initiatives, and preserving traditional livelihoods in primate range countries are all part of a comprehensive solution. Despite the existing threats to primate survival, we are adamant that primate conservation is not yet a lost cause. We still have the opportunity to reduce the human impact to primates and their habitats, but that demands raising greater local, regional and global public awareness of the plight of the world’s primates and the costs of their loss to ecosystem health, human culture and ultimately human survival.

Pseudomonas putida KT2440 encodes 23 alternative sigma factors. The fliA gene, which encodes sigma 28, is in a cluster with other genes involved in flagella biosynthesis and chemotaxis. Reverse transcriptase-PCR revealed that this cluster is comprised of four independent transcriptional units: flhAF, fleNfliA, cheYZA and cheBmotAB. We generated a nonpolar fliA mutant by homologous recombination and tested its motility, adhesion to biotic and abiotic surfaces, and responses to various stress conditions. The mutant strain was nonmotile and exhibited decreased capacity to bind to corn seeds, although its ability to colonize the rhizosphere of plants was unaffected. The mutant was also affected in binding to abiotic surfaces and its ability to form biofilms decreased by almost threefold. In the fliA mutant background expression of 25 genes was affected: two genes were upregulated and 23 genes were downregulated. In addition to a number of motility and chemotaxis genes, the fliA gene product is also necessary for the expression of some genes potentially involved in amino acid utilization or stress responses; however, we were unable to assign specific phenotypes linked to these genes since the fliA mutant used the same range of amino acids as the parental strain, and was as tolerant as the wild type to stress imposed by heat, antibiotics, NaCl, sodium dodecyl sulfate, H2O2 and benzoate. Based on the sequence alignment of promoters recognized by FliA and genome in silico analysis, we propose that P. putida sigma 28 recognizes a TCAAG-t-N-12-GCCGATA consensus sequence located between -34 and -8 and that this sequence is preferentially associated with an AT-rich upstream region., ISI Document Delivery No.: 619BU Times Cited: 0 Cited Reference Count: 41 Juan Rodriguez-Herva, Jose Duque, Estrella Antonia Molina-Henares, Maria Navarro-Aviles, Gloria van Dillewijn, Pieter de la Torre, Jesus Molina-Henares, Antonio J. Sanchez-de la Campa, Ana Ann Ran, F. Segura, Ana Shingler, Victoria Ramos, Juan-Luis ERA-NET [GEN2006-27750-C5-5-E/SYS]; CONSOLIDER-INGENIO [CSD2007-00005]; Junta de Andalucia [CIV-3010] This study was supported by the following grants: ERA-NET (GEN2006-27750-C5-5-E/SYS), CONSOLIDER-INGENIO (CSD2007-00005) and CIV-3010 from Junta de Andalucia. We thank A. Hurtado for DNA sequencing, M.M. Fandila and C. Lorente for secretarial assistance, and K. Shashok and B. Pakuts for improving the use of English in the manuscript. Wiley-blackwell publishing, inc Malden

Usando el método variacional y la aproximación de masa efectiva calculamos la energía de enlace de impurezas donadoras en puntos cuánticos de GaAs/Ga Al As 1−x x con geometría cúbica, para tres valores de la presión hidrostática externa. Presentamos los resultados en función de la posición de la impureza en las direcciones x, y z; de las diagonales en los planos x-z, x-y, y de una diagonal en la heteroestructura; además como función de la presión hidrostática externa en la dirección z. La energía de enlace disminuye conforme la impureza se acerca a las paredes de la heteroestructura y aumenta según lo hace la presión hidrostática externa.

Using the variational method within the effective-mass approximation we calculated the binding energy of a shallow donor impurity in quantum dots GaAs/Ga1-x Alx As , with cubic geometry for three different applied values of the hydrostatic pressure. We present results as a function of the position of the donor impurity in the x and z directions, and in the x-z, x-y plane diagonal, and the heterostructure diagonal; moreover, as a function of the applied hydrostatic pressure applied in z direction. The binding energy decrease according to the impurity is near to the edge of the heterostructure and increase when hydrostatic pressure increase., Usando el método variacional y la aproximación de masa efectiva calculamos la energía de enlace de impurezas donadoras en puntos cuánticos de GaAs/Ga Al As 1-x x con geometría cúbica, para tres valores de la presión hidrostática externa. Presentamos los resultados en función de la posición de la impureza en las direcciones x, y z; de las diagonales en los planos x-z, x-y, y de una diagonal en la heteroestructura; además como función de la presión hidrostática externa en la dirección z. La energía de enlace disminuye conforme la impureza se acerca a las paredes de la heteroestructura y aumenta según lo hace la presión hidrostática externa.

Usando el método variacional y la aproximación de masa efectiva calculamos la energía de enlace de impurezas donadoras en puntos cuánticos de GaAs/Ga Al As 1−x x con geometría cúbica, para tres valores de la presión hidrostática externa. Presentamos los resultados en función de la posición de la impureza en las direcciones x, y z; de las diagonales en los planos x-z, x-y, y de una diagonal en la heteroestructura; además como función de la presión hidrostática externa en la dirección z. La energía de enlace disminuye conforme la impureza se acerca a las paredes de la heteroestructura y aumenta según lo hace la presión hidrostática externa.

Usando el método variacional y la aproximación de masa efectiva calculamos la energía de enlace de impurezas donadoras en puntos cuánticos de GaAs/Ga Al As 1−x x con geometría cúbica, para tres valores de la presión hidrostática externa. Presentamos los resultados en función de la posición de la impureza en las direcciones x, y z; de las diagonales en los planos x-z, x-y, y de una diagonal en la heteroestructura; además como función de la presión hidrostática externa en la dirección z. La energía de enlace disminuye conforme la impureza se acerca a las paredes de la heteroestructura y aumenta según lo hace la presión hidrostática externa.

Usando el método variacional y la aproximación de masa efectiva calculamos la energía de enlace de impurezas donadoras en puntos cuánticos de GaAs/Ga Al As 1−x x con geometría cúbica, para tres valores de la presión hidrostática externa. Presentamos los resultados en función de la posición de la impureza en las direcciones x, y z; de las diagonales en los planos x-z, x-y, y de una diagonal en la heteroestructura; además como función de la presión hidrostática externa en la dirección z. La energía de enlace disminuye conforme la impureza se acerca a las paredes de la heteroestructura y aumenta según lo hace la presión hidrostática externa.

Usando el método variacional y la aproximación de masa efectiva calculamos la energía de enlace de impurezas donadoras en puntos cuánticos de GaAs/Ga Al As 1−x x con geometría cúbica, para tres valores de la presión hidrostática externa. Presentamos los resultados en función de la posición de la impureza en las direcciones x, y z; de las diagonales en los planos x-z, x-y, y de una diagonal en la heteroestructura; además como función de la presión hidrostática externa en la dirección z. La energía de enlace disminuye conforme la impureza se acerca a las paredes de la heteroestructura y aumenta según lo hace la presión hidrostática externa.

Using the variational method within the effective-mass approximation we calculated the binding energy of a shallow donor impurity in quantum dots GaAs/Ga1-x Alx As , with cubic geometry for three different applied values of the hydrostatic pressure. We present results as a function of the position of the donor impurity in the x and z directions, and in the x-z, x-y plane diagonal, and the heterostructure diagonal; moreover, as a function of the applied hydrostatic pressure applied in z direction. The binding energy decrease according to the impurity is near to the edge of the heterostructure and increase when hydrostatic pressure increase., Usando el método variacional y la aproximación de masa efectiva calculamos la energía de enlace de impurezas donadoras en puntos cuánticos de GaAs/Ga Al As 1-x x con geometría cúbica, para tres valores de la presión hidrostática externa. Presentamos los resultados en función de la posición de la impureza en las direcciones x, y z; de las diagonales en los planos x-z, x-y, y de una diagonal en la heteroestructura; además como función de la presión hidrostática externa en la dirección z. La energía de enlace disminuye conforme la impureza se acerca a las paredes de la heteroestructura y aumenta según lo hace la presión hidrostática externa.

The viscous, three-dimensional, flowfields of UH60 and BERP rotors are calculated for lifting hover configurations using a Navier-Stokes computational fluid dynamics method with a view to understand the importance of planform effects on the airloads. In this method, the induced effects of the wake, including the interaction of tip vortices with successive blades, are captured as a part of the overall flowfield solution without prescribing any wake models. Numerical results in the form of surface pressures, hover performance parameters, surface skin friction and tip vortex patterns, and vortex wake trajectory are presented at two thrust conditions for UH60 and BERP rotors. Comparison of results for the UH60 model rotor show good agreement with experiments at moderate thrust conditions. Comparison of results with equivalent rectangular UH60 blade and BERP blade indicates that the BERP blade, with an unconventional planform, gives more thrust at the cost of more power and a reduced Figure of Merit. The high thrust conditions considered produce severe shock-induced flow separation for UH60 blade, while the BERP blade develops more thrust and minimal separation. The BERP blade produces a tighter tip vortex structure compared with the UH60 blade. These results and the discussion presented bring out the similarities and differences between the two rotors.