794 resultados para Constructed Preferences
Resumo:
Many researchers have used theoretical or empirical measures to assess social benefits in transport policy implementation. However, few have measured social benefits by using discount rates, including the intertemporal preference rate of users, the private investment discount rate, and the intertemporal preference rate of the government. In general, the social discount rate used is the same for all social actors. This paper aims to assess a new method by integrating different types of discount rates belonging to different social actors to measure the real benefits of each actor in the short term, medium term, and long term. A dynamic simulation is provided by a strategic land use and transport interaction model. The method was tested by optimizing a cordon toll scheme in Madrid, Spain. Socioeconomic efficiency and environmental criteria were considered. On the basis of the modified social welfare function, the effects on the measure of social benefits were estimated and compared with the classical welfare function measures. The results show that the use of more suitable discount rates for each social actor had an effect on the selection and definition of optimal strategy of congestion pricing. The usefulness of the measure of congestion toll declines more quickly over time. This result could be the key to understanding the relationship between transport system policies and the distribution of social actors? benefits in a metropolitan context.
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Dominance measuring methods are a new approach to deal with complex decision-making problems with imprecise information. These methods are based on the computation of pairwise dominance values and exploit the information in the dominance matrix in dirent ways to derive measures of dominance intensity and rank the alternatives under consideration. In this paper we propose a new dominance measuring method to deal with ordinal information about decision-maker preferences in both weights and component utilities. It takes advantage of the centroid of the polytope delimited by ordinal information and builds triangular fuzzy numbers whose distances to the crisp value 0 constitute the basis for the de?nition of a dominance intensity measure. Monte Carlo simulation techniques have been used to compare the performance of this method with other existing approaches.
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Teniendo en cuenta que no hay nada que se escape de la moda 1, y extendiendonos más allá de esta manida discusión sobre intersecciones formales, esta investigación propone la pasarela como un lugar real de mediación entre moda y arquitectura. Asumiendo esta condición, la pasarela encarna nuevos modos de producción apropiándose de su espacio y estructura, y convierténdose en una máquina capaz de generar múltiples y más bien infinitos significados. La moda es sin duda un proyecto creativo, que ha venido utilizando la pasarela como un marco para la reordenación de su narrativa visual, renovándose asi mismo como fenómeno social. Este proyecto de investigación plantea, que contrariamente las tipologías actuales de las pasarelas no nos facilitan la comprensión de una colección – que suele ser el objetivo principal. Presentan en cambio un entorno en el que se acoplan diferentes formatos visuales, -con varias capas-, conviéndolo en una compleja construcción y provocando nunerosas fricciones con el espacio-tiempo-acción durante el proceso de creación de otros territorios. Partiendo de la idea de la pasarela como un sistema, en el que sus numerosas variables pueden producir diversas combinaciones, esta investigación plantea la hipótesis por la cual un nuevo sistema de pasarela se estaría formando enteramente con capas de información. Este escenario nos conduciría a la inmersión final de la moda en los tejidos de la virtualidad. Si bien el debate sobre la relevancia de los desfiles de moda se ha vuelto más evidente hoy en día, esta investigación especula con la posibilidad del pensamiento arquitectónico y como este puede introducir metodologías de análisis en el marco de estos desfiles de moda, proponiendo una lectura de la pasarela como un sistema de procedimientos específicos inherente a los proyectos/procesos de la arquitectura. Este enfoque enlaza ambas prácticas en un territorio común donde el espacio, el diseño, el comportamiento, el movimiento, y los cuerpos son ordenados/organizados en la creación de estas nuevas posibilidades visuales, y donde las interacciones activan la generación de la novedad y los mensajes. PALABRAS CLAVES moda, sistema, virtual, información, arquitectura Considering that there is nothing left untouched by fashion2, and going beyond the already exhausted discussion about formal intersections, this research introduces the catwalk as the real arena of mediation between fashion and architecture. By assuming this condition, the catwalk embodies new modes of production that appropriates its space and turns it into a machine for generating multiple if not infinite meanings. Fashion, as a creative project, has utilized the catwalk as a frame for rearranging its visual narrative and renewing itself as social phenomena. This research disputes, however, that the current typologies of catwalks do not facilitate the understanding of the collection – as its primary goal - but, instead, present an environment composed of multi-layered visual formats, becoming a complex construct that collides space-time-action in the creation of other territories. Departing from the analysis of the catwalk as a system and how its many variables can produce diverse combinations, this research presents the hypothesis that a new system is being formed entirely built out of information. Such scenario indicates fashion´s final immersion into the fabrics of virtuality. While the discussion about the relevance of fashion shows has become more evident today, this research serves as an introductory speculation on how architectural thinking can introduce methodologies of analysis within the framework of the fashion shows, by proposing a reading of the catwalk as a system through specific procedures that are inherent to architectural projects. Such approach intertwines both practices into a common territory where space, design, behaviour, movement, and bodies are organized for the creation of visual possibilities, and where interactions are triggered in the making of novelty and messages. KEYWORDS fashion, system, virtual, information, architectural
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There exist different ways for defining a welfare function. Traditionally, welfare economic theory foundation is based on the Net Present Value (NPV) calculation where the time dependent preferences of considered agents are taken into account. However, the time preferences, remains a controversial subject. Currently, the traditional approach employs a unique discount rate for various agents. Nevertheless, this way of discounting appears inconsistent with sustainable development. New research work suggests that the discount rate may not be a homogeneous value. The discount rates may change following the individual’s preferences. A significant body of evidence suggests that people do not behave following a constant discount rate. In fact, UK Government has quickly recognized the power of the arguments for time-varying rates, as it has done in its official guidance to Ministries on the appraisal of investments and policies. Other authors deal with not just time preference but with uncertainty about future income (precautionary saving). In a situation in which economic growth rates are similar across time periods, the rationale for declining social optimal discount rates is driven by the preferences of the individuals in the economy, rather than expectations of growth. However, these approaches have been mainly focused on long-term policies where intergenerational risks may appear. The traditional cost-benefit analysis (CBA) uses a unique discount rate derived from market interest rates or investment rates of return for discounting the costs and benefits of all social agents included in the CBA. However, recent literature showed that a more adequate measure of social benefit is possible by using different discount rates including inter-temporal preferences rate of users, private investment discount rate and intertemporal preferences rate of government. Actually, the costs of opportunity may differ amongst individuals, firms, governments, or society in general, as do the returns on savings. In general, the firms or operators require an investment rate linked to the current return on savings, while the discount rate of consumers-users depends on their time preferences with respect of the current and the future consumption, as well as society can take into account the intergenerational well-being, adopting a lower discount rate for today’s generation. Time discount rate of social actors (users, operators, government and society) places a lower value in a future gain, but the uncertainty about future income strongly determines the individual preferences. These time and uncertainty depends on preferences and should be integrated into a transport policy formulation that may have significant social impacts. The discount rate of a user cannot be the same than the operator’s discount rate. The preferences of both are different. In addition, another school of thought suggests that people, such as a social group, may have different attitudes towards future costs and benefits. Particularly, the users have different discount rates related to their income. Some research work tried to modify user discount rates using a compensating weight which represents the inverse of household income level. The inter-temporal preferences are a proxy of the willingness to pay during the time. Its consideration is important in order to make acceptable or not a policy or investment
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Dominance measuring methods are an approach for dealing with complex decision-making problems with imprecise information within multi-attribute value/utility theory. These methods are based on the computation of pairwise dominance values and exploit the information in the dominance matrix in different ways to derive measures of dominance intensity and rank the alternatives under consideration. In this paper we review dominance measuring methods proposed in the literature for dealing with imprecise information (intervals, ordinal information or fuzzy numbers) about decision-makers? preferences and their performance in comparison with other existing approaches, like SMAA and SMAA-II or Sarabando and Dias? method.
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Abstract:The aim of this paper is to review the literature on voting systems based on Condorcet and Borda. We compared and classified them. Also we referred to some strengths and weaknesses of voting systems and finally in a case study, we made use of the Borda voting system for collective decision making in the Salonga National Park in the Democratic Republic of Congo. Resumen: el objetivo de este trabajo es hacer una revisión bibliográfica de los sistemas de votación basados en Condorcet y Borda. Se ha comparado y clasificado los mismos. Así mismo se ha hecho referencia a algunas debilidades y fortalezas de los sistemas de votación y por último en un caso de estudio, se ha hecho uso del sistema de votación de Borda para la toma de decisión colectiva en el Parque Nacional de Salonga en la República Democrática del Congo.
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• Premise of the study: The presence of compatible fungi is necessary for epiphytic orchid recruitment. Thus, identifying associated mycorrhizal fungi at the population level is essential for orchid conservation. Recruitment patterns may also be conditioned by factors such as seed dispersal range and specific environmental characteristics. • Methods: In a forest plot, all trees with a diameter at breast height >1 cm and all individuals of the epiphytic orchid Epidendrum rhopalostele were identified and mapped. Additionally, one flowering individual of E. rhopalostele per each host tree was randomly selected for root sampling and DNA extraction. • Key results: A total of 239 E. rhopalostele individuals were located in 25 of the 714 potential host trees. Light microscopy of sampled roots showed mycorrhizal fungi in 22 of the 25 sampled orchids. Phylogenetic analysis of ITS1-5.8S-ITS2 sequences yielded two Tulasnella clades. In four cases, plants were found to be associated with both clades. The difference between univariate and bivariate K functions was consistent with the random labeling null model at all spatial scales, indicating that trees hosting clades A and B of Tulasnella are not spatially segregated. The analysis of the inhomogenous K function showed that host trees are not clustered, suggesting no limitations to population-scale dispersal. χ2 analysis of contingency tables showed that E. rhopalostele is more frequent on dead trees than expected. • Conclusions: Epidendrum rhopalostele establishes mycorrhizal associations with at least two different Tulasnella species. The analysis of the distribution patterns of this orchid suggests a microsite preference for dead trees and no seed dispersal limitation.
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Este proyecto se encuadra dentro de los estudios de impacto que están produciendo en las empresas el desarrollo e incorporación de las nuevas tecnologías, y más concretamente la implantación de las aplicaciones provenientes de la denominada web 2.0. Se conoce con este nombre a las herramientas web que permiten una comunicación bidireccional, es decir, el usuario y la empresa pueden intercambiar opiniones, de manera que el usuario adquiere un nuevo papel más protagonista, presentando ideas, aclaraciones, gustos, críticas...que son tenidas en cuenta por la empresa para realizar su actividad. De esta manera se ha roto con el modelo anterior donde el usuario solo podía consultar la información de una página web, era simple receptor de la información. El objetivo de este estudio es conocer cómo las empresas están incorporando estas tecnologías 2.0 a su estrategia empresarial, y cómo términos como innovación abierta o co-creación están tomando mayor importancia en el entorno empresarial gracias a estas nuevas tecnologías. Si bien existen estudios a nivel de consultoría que generalmente aportan información sobre cuáles son las plataformas 2.0 más utilizadas en el mundo empresarial, no se han encontrado hasta ahora estudios que vinculen estas plataformas entre ellas y con la estructura empresarial, para poder definir un perfil de la organización que trabaja con ellas o el nivel de madurez de la incorporación de estas tecnologías en las organizaciones. Analizar cualitativamente estos aspectos, significa estudiar los nuevos conceptos incorporados a las tecnologías 2.0 en la empresa. Un análisis cuantitativo nos llevaría a estudiar de manera práctica que tipo de recursos y en qué cantidad se están utilizando y su vinculación con la estructura de la organización. Para ello: En una primera parte, nos centraremos en las diferentes formas en las que se puede acceder a Internet, y a continuación enfocaremos el estudio en los dispositivos móviles que nos permiten la conexión desde cualquier lugar y en cualquier instante. Con esto conseguiremos tener una situación actual del mercado de las TIC y veremos cómo las empresas han ido construyendo nuevas políticas para cambiar su estrategia con el fin de estar presentes en los nuevos dispositivos móviles y no perder cuota de mercado. Tras ello, veremos porqué conceptos como el de innovación abierta y proceso de co-creación han sido posibles gracias a la implantación de las tecnologías 2.0 en el ámbito empresarial, facilitando que la empresa y el usuario final cooperen y vayan de la mano en una misma dirección; la empresa se surte de las aportaciones que los usuarios ofrecen, y por otra parte el usuario se siente valorado por la empresa para conseguir la meta final. Es aquí donde comprobaremos la transformación que ha sufrido la empresa en sus distintos sectores departamentales (marketing, ventas, recursos humanos y atención al cliente) como consecuencia de la incorporación de las herramientas 2.0 al mundo laboral. Por todo ello, se enumerarán los distintos usos que realizan las empresas de las redes social más habituales, y además se describirán las principales herramientas y/o aplicaciones para monitorizar las redes sociales que servirán a la empresa para hacer un seguimiento de las mismas. La segunda parte del proyecto será un caso práctico y servirá para ofrecer una visión más real del estado actual de las empresas y su relación con las redes sociales. Para la recopilación de los datos se han escogido las empresas que pertenecen al sector de la “Fabricación de productos informáticos, electrónicos y ópticos”. En cuento a las redes sociales elegidas, han sido Facebook y Twitter. Este estudio práctico nos hará entender mejor el impacto directo que tienen las redes sociales en la actividad diaria de las empresas. Finalmente se realizarán una serie de consideraciones a modo de directrices que servirán para tratar de entender cómo se están utilizando las redes sociales en el entorno empresarial y cuál puede ser la manera más óptima de utilizarlas según el estudio presentado. ABSTRACT. This project is part of the impact studies arisen in companies by the development and incorporation of new technologies and, specifically, by the implementation of applications from the so-called web 2.0. That is how we call the web tools that allow bidirectional communication, this is, user and company can exchange opinions, in such a way that users acquire a leading role, submitting ideas, explanations, preferences, criticism... considered by the company when performing its activities. This way, we have broken with the previous model, where users could only check information from a web page and were simple information recipients. The objective of this study is to get to know how companies are incorporating these technologies 2.0 to their business strategy and how terms such as open innovation or co-creation are becoming more important in the business sphere thanks to these new technologies. Even if there are consulting studies that generally provide information about which are the platforms 2.0 more used in the business world, no studies have been found until now that link such platforms among them and with the business structure, in order to define a profile of the organization that works with them or the level of development of the incorporation of these technologies in the organizations. A qualitative analysis of these aspects involves studying the new concepts incorporated to technologies 2.0 by companies. A qualitative analysis would lead us to study in a practical manner what kind of resources and what amount are being used and their relation with the organization structure. Therefore: First, we will focus on the different ways to gain access to the Internet and, afterwards, we will focus the study on mobile devices that allow us to be connected everywhere any time. This way, we will manage to obtain a present situation of the ICT market and we will see how companies have constructed new policies to change their strategy in order to be present in the new mobile devices without losing their market share. Later, we will review why concepts such as open innovation and co-creation process have been possible thanks to the implementation of technologies 2.0 in the business environment, facilitating that companies and final users cooperate and walk hand in hand in the same direction; companies stock up on the contributions offered by users and, on the other hand, users feel appreciated by companies in the achievement of the final goal. Here we will confirm the transformation suffering by companies in different department sectors (marketing, sales, human resources and customer service) as a result of the incorporation of tools 2.0 to the work environment. Therefore, we will enumerate the different uses that companies make of the most common social networks, describing the main tools and/or applications to monitor social networks used by companies to follow them up. The second part of the project will be a case study to offer a more real vision of the present status of companies and their relation with social networks. To collect the data, we have selected companies from the “Manufacture of computer, electronic and optical products” industry. The social networks chosen are Facebook and Twitter. This case study will help us to get a better understanding of the direct impact of social networks in companies’ daily activity. Finally, we will offer a series of considerations and guidelines to try to understand how are social networks being used in the business environment and what can be the most suitable manner to use them according to this study.
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Proteins can be very tolerant to amino acid substitution, even within their core. Understanding the factors responsible for this behavior is of critical importance for protein engineering and design. Mutations in proteins have been quantified in terms of the changes in stability they induce. For example, guest residues in specific secondary structures have been used as probes of conformational preferences of amino acids, yielding propensity scales. Predicting these amino acid propensities would be a good test of any new potential energy functions used to mimic protein stability. We have recently developed a protein design procedure that optimizes whole sequences for a given target conformation based on the knowledge of the template backbone and on a semiempirical potential energy function. This energy function is purely physical, including steric interactions based on a Lennard-Jones potential, electrostatics based on a Coulomb potential, and hydrophobicity in the form of an environment free energy based on accessible surface area and interatomic contact areas. Sequences designed by this procedure for 10 different proteins were analyzed to extract conformational preferences for amino acids. The resulting structure-based propensity scales show significant agreements with experimental propensity scale values, both for α-helices and β-sheets. These results indicate that amino acid conformational preferences are a natural consequence of the potential energy we use. This confirms the accuracy of our potential and indicates that such preferences should not be added as a design criterion.
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Avian plumage has long been used to test theories of sexual selection, with humans assessing the colors. However, many birds see in the ultraviolet (<400 nm), to which humans are blind. Consequently, it is important to know whether natural variation in UV reflectance from plumage functions in sexual signaling. We show that female starlings rank males differently when UV wavelengths are present or absent. Principal component analysis of ≈1300 reflectance spectra (300–700 nm) taken from sexually dimorphic plumage regions of males predicted preference under the UV+ treatment. Under UV− conditions, females ranked males in a different and nonrandom order, but plumage reflectance in the human visible spectrum did not predict choice. Natural variation in UV reflectance is thus important in avian mate assessment, and the prevailing light environment can have profound effects on observed mating preferences.
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Peer reviewed
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Within hours after the ingestion of a blood meal, the mosquito midgut epithelium synthesizes a chitinous sac, the peritrophic matrix. Plasmodium ookinetes traverse the peritrophic matrix while escaping the mosquito midgut. Chitinases (EC 3.2.1.14) are critical for parasite invasion of the midgut: the presence of the chitinase inhibitor, allosamidin, in an infectious blood meal prevents oocyst development. A chitinase gene, PgCHT1, recently has been identified in the avian malaria parasite P. gallinaceum. We used the sequence of PgCHT1 to identify a P. falciparum chitinase gene, PfCHT1, in the P. falciparum genome database. PfCHT1 differs from PgCHT1 in that the P. falciparum gene lacks proenzyme and chitin-binding domains. PfCHT1 was expressed as an active recombinant enzyme in Escherichia coli. PfCHT1 shares with PgCHT1 a substrate preference unique to Plasmodium chitinases: the enzymes cleave tri- and tetramers of GlcNAc from penta- and hexameric oligomers and are unable to cleave smaller native chitin oligosaccharides. The pH activity profile of PfCHT1 and its IC50 (40 nM) to allosamidin are distinct from endochitinase activities secreted by P. gallinaceum ookinetes. Homology modeling predicts that PgCHT1 has a novel pocket in the catalytic active site that PfCHT1 lacks, which may explain the differential sensitivity of PfCHT1 and PgCHT1 to allosamidin. PfCHT1 may be the ortholog of a second, as yet unidentified, chitinase gene of P. gallinaceum. These results may allow us to develop novel strategies of blocking human malaria transmission based on interfering with P. falciparum chitinase.
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To create a universal system for the control of gene expression, we have studied methods for the construction of novel polydactyl zinc finger proteins that recognize extended DNA sequences. Elsewhere we have described the generation of zinc finger domains recognizing sequences of the 5′-GNN-3′ subset of a 64-member zinc finger alphabet. Here we report on the use of these domains as modular building blocks for the construction of polydactyl proteins specifically recognizing 9- or 18-bp sequences. A rapid PCR assembly method was developed that, together with this predefined set of zinc finger domains, provides ready access to 17 million novel proteins that bind the 5′-(GNN)6-3′ family of 18-bp DNA sites. To examine the efficacy of this strategy in gene control, the human erbB-2 gene was chosen as a model. A polydactyl protein specifically recognizing an 18-bp sequence in the 5′-untranslated region of this gene was converted into a transcriptional repressor by fusion with Krüppel-associated box (KRAB), ERD, or SID repressor domains. Transcriptional activators were generated by fusion with the herpes simplex VP16 activation domain or with a tetrameric repeat of VP16’s minimal activation domain, termed VP64. We demonstrate that both gene repression and activation can be achieved by targeting designed proteins to a single site within the transcribed region of a gene. We anticipate that gene-specific transcriptional regulators of the type described here will find diverse applications in gene therapy, functional genomics, and the generation of transgenic organisms.
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The “shape” of a female mating preference is the relationship between a male trait and the probability of acceptance as a mating partner. The shape of preferences is important in many models of sexual selection, mate recognition, communication, and speciation, yet it has rarely been measured precisely. Here I examine preference shape for male calling song in a bushcricket (katydid). Preferences change dramatically between races of a species, from strongly directional to broadly stabilizing (but with a net directional effect). Preference shape generally matches the distribution of the male trait. This is compatible with a coevolutionary model of signal-preference evolution, although it does not rule out an alternative model, sensory exploitation. Preference shapes are shown to be genetic in origin.