2,755 research outputs found

    Patrones de distribución de la cotorra argentina (Myiopsitta monachus) en un hábitat urbano

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    Varias especies invasoras han demostrado tener una marcada preferencia por los hábitats urbanos. El estudio de las variables responsables de la distribución de estas especies dentro de hábitats urbanos debe permitir predecir cuáles son las variables ambientales indicativas de su hábitat preferido, y diseñar las características del paisaje que hacen a estas áreas ser menos favorables para estas especies. La cotorra argentina Myiopsitta monachus es una especie invasora en muchos países de América y de Europa, siendo las ciudades uno de los hábitats más comunes para esta especie en las áreas invadidas. El propósito de este estudio fue identificar los factores principales que determinan la distribución de la cotorra argentina en Barcelona, una de las ciudades en el mundo con una de las densidades más grande de cotorras. Hemos definido nuestro modelo basado en ocho variables preseleccionadas mediante un modelo lineal generalizado (GLZ) y evaluamos el poder de cada modelo a través de un análisis de inferencia multimodelo basado en el valor AIC. Utilizamos la densidad de cotorra argentina como variable dependiente y restringimos el análisis a aquellos barrios de la ciudad ocupados por la especie, obteniendo un modelo con dos variables clave que explicaban la distribución de la especie. Las cotorras argentinas eran más abundantes en aquellos barrios con alta densidad de árboles y con un alto porcentaje de personas mayores de 65 años. Esto se interpreta por el hecho de que las cotorras utilizan los árboles como fuente de alimento y como lugar de nidificación, y porque las personas mayores a menudo alimentan a la especie. Los datos apoyan la hipótesis de ‘la actividad humana’ para explicar cómo las especies invasoras pueden exitosamente establecerse en un hábitat no nativo, y subraya cómo la limitación de las fuentes de alimento, especialmente la comida suministrada por los seres humanos, puede ser la forma más sencilla de ejercer cierto control sobre las poblaciones de cotorra argentina.Several invasive species have been shown to have a marked preference for urban habitats. The study of the variables responsible for the distribution of these species within urban habitats should allow to predict which environmental variables are indicative of preferred habitat, and to design landscape characteristics that make these areas less conducive to these species. The Monk parakeet Myiopsitta monachus is an invasive species in many American and European countries, and cities are one of its most usual habitats in invaded areas. The aim of this paper was to identify the main factors that determine distribution of the Monk parakeet in Barcelona, one of the cities in the world with the highest parakeet density. We defined our model based on eight preselected variables using a generalized linear model (GLZ) and evaluated the strength of support for each model using the AIC–based multi–model inference approach. We used parakeet density as a dependent variable, and an analysis restricted to occupied neighbourhoods provided a model with two key variables to explain the distribution of the species. Monk parakeets were more abundant in neighbourhoods with a high density of trees and a high percentage of people over 65 years. This is interpreted by the fact that parakeets use trees as food sources and support for the nests, and that older people often feed the species. Data support the ‘human–activity’ hypothesis to explain how invasive species can successfully establish in a non–native habitat, and stress how limiting food resources, especially food supplied by humans, may be the easiest way to exert some control on Monk parakeet populations.Varias especies invasoras han demostrado tener una marcada preferencia por los hábitats urbanos. El estudio de las variables responsables de la distribución de estas especies dentro de hábitats urbanos debe permitir predecir cuáles son las variables ambientales indicativas de su hábitat preferido, y diseñar las características del paisaje que hacen a estas áreas ser menos favorables para estas especies. La cotorra argentina Myiopsitta monachus es una especie invasora en muchos países de América y de Europa, siendo las ciudades uno de los hábitats más comunes para esta especie en las áreas invadidas. El propósito de este estudio fue identificar los factores principales que determinan la distribución de la cotorra argentina en Barcelona, una de las ciudades en el mundo con una de las densidades más grande de cotorras. Hemos definido nuestro modelo basado en ocho variables preseleccionadas mediante un modelo lineal generalizado (GLZ) y evaluamos el poder de cada modelo a través de un análisis de inferencia multimodelo basado en el valor AIC. Utilizamos la densidad de cotorra argentina como variable dependiente y restringimos el análisis a aquellos barrios de la ciudad ocupados por la especie, obteniendo un modelo con dos variables clave que explicaban la distribución de la especie. Las cotorras argentinas eran más abundantes en aquellos barrios con alta densidad de árboles y con un alto porcentaje de personas mayores de 65 años. Esto se interpreta por el hecho de que las cotorras utilizan los árboles como fuente de alimento y como lugar de nidificación, y porque las personas mayores a menudo alimentan a la especie. Los datos apoyan la hipótesis de ‘la actividad humana’ para explicar cómo las especies invasoras pueden exitosamente establecerse en un hábitat no nativo, y subraya cómo la limitación de las fuentes de alimento, especialmente la comida suministrada por los seres humanos, puede ser la forma más sencilla de ejercer cierto control sobre las poblaciones de cotorra argentina

    The objective selection as an alternative to reduce the negative impact of corruption on the activity of administrative contracting, in Colombia

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    La contratación administrativa ha sido, desde hace muchas décadas, uno de los problemas más grandes que enfrenta el Estado, en la medida en que se ha ido convirtiendo en uno de los bastiones de la corrupción, ya que mediante la contratación los recursos del Estado han sido objeto de dilapidación y de acciones que riñen con la rectitud, sujeción a las normas y cumplimiento de lo contratado. En el presente artículo se aborda la problemática enunciada, en una exploración bibliográfica, cuyo objetivo es mostrar las bondades y defectos de la Selección Objetiva, como alternativa para luchar contra la corrupción inmersa en la figura de la contratación con el Estado. El grupo pudo establecer cómo la selección objetiva es realmente una solución, en la medida que se la complemente con una cultura de cumplimiento, de buena fe y deseos de servir, a través de la contratación que utiliza el Estado para cumplir sus funciones constitucionales y satisfacer las necesidades de los coasociados. Administrative contracting has been, for many decades, one of the biggest problems faced by the State, to the extent that it has become one of the bastions of corruption, since through contracting the State resources have been the object of dilapidation and actions that conflict with rectitude, subject to the rules and compliance with the contract. This article addresses the stated problem, in a bibliographic exploration, whose objective is to show the benefits and defects of Objective Selection, as an alternative to fight against corruption immersed in the figure of contracting with the State. The group was able to establish how objective selection is really a solution, to the extent that it is complemented by a culture of compliance, in good faith and a desire to serve, through the contracting that the State uses to fulfill its constitutional functions and satisfy the needs of partners

    ALBAYZIN 2018 spoken term detection evaluation: a multi-domain international evaluation in Spanish

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    [Abstract] Search on speech (SoS) is a challenging area due to the huge amount of information stored in audio and video repositories. Spoken term detection (STD) is an SoS-related task aiming to retrieve data from a speech repository given a textual representation of a search term (which can include one or more words). This paper presents a multi-domain internationally open evaluation for STD in Spanish. The evaluation has been designed carefully so that several analyses of the main results can be carried out. The evaluation task aims at retrieving the speech files that contain the terms, providing their start and end times, and a score that reflects the confidence given to the detection. Three different Spanish speech databases that encompass different domains have been employed in the evaluation: the MAVIR database, which comprises a set of talks from workshops; the RTVE database, which includes broadcast news programs; and the COREMAH database, which contains 2-people spontaneous speech conversations about different topics. We present the evaluation itself, the three databases, the evaluation metric, the systems submitted to the evaluation, the results, and detailed post-evaluation analyses based on some term properties (within-vocabulary/out-of-vocabulary terms, single-word/multi-word terms, and native/foreign terms). Fusion results of the primary systems submitted to the evaluation are also presented. Three different research groups took part in the evaluation, and 11 different systems were submitted. The obtained results suggest that the STD task is still in progress and performance is highly sensitive to changes in the data domain.Ministerio de Economía y Competitividad; TIN2015-64282-R,Ministerio de Economía y Competitividad; RTI2018-093336-B-C22Ministerio de Economía y Competitividad; TEC2015-65345-PXunta de Galicia; ED431B 2016/035Xunta de Galicia; GPC ED431B 2019/003Xunta de Galicia; GRC 2014/024Xunta de Galicia; ED431G/01Xunta de Galicia; ED431G/04Agrupación estratéxica consolidada; GIU16/68Ministerio de Economía y Competitividad; TEC2015-68172-C2-1-

    Empty Urbanism: the bursting of the Spanish housing bubble

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    The depth of the Spanish housing crisis manifests itself in the collapse of construction activity and in the amount of housing and land stocks. The geography of the crisis shows its widespread nature, and the intensity of the previous bubble explains spatial differences. Resulting from this collapse are some problematic areas of 'empty urbanism'. An enormous land bubble, emerging from the peculiar Spanish urban development model, was a key factor in the impacts - caused by the crisis - on the territory and land-use plans. The crisis has demonstrated the unsustainability of this and the urgency of change in the existing land-use plans

    Hidradenitis suppurativa: a review

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    Hidradenitis suppurativa (HS) is a chronic inflammatory disorder that is characterized by recurrence, as well as the characteristic location of skin lesions. Patients usually develop very painful inflammatory nodules that generally end in the formation of multiple abscesses and fistulas that typically occur in the skin of the axillary, inguinal, buttock, and perianal folds. It significantly affects the quality of life of patients, leaving physical, economic and psychological sequelae. There is a wide therapeutic arsenal available, but each patient must be individualized and the best possible treatment determined. Early assessment and intensive treatment of the disease can prevent and even avoid significant sequelae and permanent deformities

    Current strategies for the reconstruction of the nipple-areola complex: a review

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    The reconstruction of the nipple-areola complex after a mastectomy is essential for the bio-psycho-social recovery of the patient, it is generally performed 4 to 6 months after surgery and there are multiple surgical reconstruction techniques depending on the experience of the surgeon and of the individual characteristics of the patients. The most widely used for its safety and for having shown the best results is the local flap technique combined with the use of autologous, alloplastic and allograft grafts. However, currently there is still no technique that shows long-term lasting results. For this reason, in this article we describe the five categories of reconstruction techniques for the nipple-areola complex that currently exist, their advantages and disadvantages, as well as the lines of research in tissue engineering in which the world is working to find a therapeutic strategy that can reproduce a nipple-areola complex with the characteristics of the biologic.

    Biodegradable electrospun scaffolds for skin wound regeneration: a review

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    Over the years, skin substitutes have been sought as an alternative for the treatment of different pathologies. In this article, we focus on describing the use of different biodegradable nanofibrillar polymers as skin substitutes in the treatment of acute and chronic wounds, obtained by the electrospinning technique. Electrospinning is a tissue engineering technique used to generate nanofibers of different polymers that are characterized by having a high surface area, low molecular weight, high resistance rates, and nanoporosity, which is why they are particularly interesting for biomedicine, with potential applicability. in the replacement of skin and tubular organs. In this context, the skin created by tissue engineering has high expectations of application in the study of treatment of skin wounds

    Reliability and tolerance comparison in water supply networks

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    The final publication is available at Springer via http://dx.doi.org/10.1007/s11269-010-9753-2Urban water supply is a high priority service and so looped networks are extensively used in order to considerably reduce the number of consumers affected by a failure. Looped networks may be redundant in connectivity and capacity. The concept of reliability has been introduced in an attempt to quantitatively measure the possibility of maintaining an adequate service for a given period. Numerous researchers have considered reliability as a measure of redundancy. This concept is usually implicit, but some researchers have even stated it explicitly. This paper shows why reliability cannot be considered a measure of redundancy given that branched networks can achieve high values of reliability and this would deny the fact that a looped network is more reliable than a branched network with a similar layout and size. To this end the paper discusses two quantitative indices for measuring expected network behavior: reliability and tolerance. These indices are calculated and a comparison is made between looped, branched, and mixed networks. © 2011 Springer Science+Business Media B.V.The authors wish to acknowledge the support received from project IDAWAS, DPI2009-11591, of the Directorate-General of Research at the Spanish Ministry of Education, the grant PAID-02-09 for a stay at the Universidad Politecnica de Valencia by the first author, and a grant MAEC-AECI 0000202066 awarded to the second author by the Ministerio de Asuntos Exteriores y Cooperacion of Spain. The use of English in this paper was revised by John Rawlins; and the revision was funded by the Universidad Politecnica de Valencia, Spain.Martínez-Rodríguez, JB.; Montalvo Arango, I.; Izquierdo Sebastián, J.; Pérez García, R. (2011). Reliability and tolerance comparison in water supply networks. 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    Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

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    A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE
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