930 resultados para Large modeling projects


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Abstract Background Spotted cDNA microarrays generally employ co-hybridization of fluorescently-labeled RNA targets to produce gene expression ratios for subsequent analysis. Direct comparison of two RNA samples in the same microarray provides the highest level of accuracy; however, due to the number of combinatorial pair-wise comparisons, the direct method is impractical for studies including large number of individual samples (e.g., tumor classification studies). For such studies, indirect comparisons using a common reference standard have been the preferred method. Here we evaluated the precision and accuracy of reconstructed ratios from three indirect methods relative to ratios obtained from direct hybridizations, herein considered as the gold-standard. Results We performed hybridizations using a fixed amount of Cy3-labeled reference oligonucleotide (RefOligo) against distinct Cy5-labeled targets from prostate, breast and kidney tumor samples. Reconstructed ratios between all tissue pairs were derived from ratios between each tissue sample and RefOligo. Reconstructed ratios were compared to (i) ratios obtained in parallel from direct pair-wise hybridizations of tissue samples, and to (ii) reconstructed ratios derived from hybridization of each tissue against a reference RNA pool (RefPool). To evaluate the effect of the external references, reconstructed ratios were also calculated directly from intensity values of single-channel (One-Color) measurements derived from tissue sample data collected in the RefOligo experiments. We show that the average coefficient of variation of ratios between intra- and inter-slide replicates derived from RefOligo, RefPool and One-Color were similar and 2 to 4-fold higher than ratios obtained in direct hybridizations. Correlation coefficients calculated for all three tissue comparisons were also similar. In addition, the performance of all indirect methods in terms of their robustness to identify genes deemed as differentially expressed based on direct hybridizations, as well as false-positive and false-negative rates, were found to be comparable. Conclusion RefOligo produces ratios as precise and accurate as ratios reconstructed from a RNA pool, thus representing a reliable alternative in reference-based hybridization experiments. In addition, One-Color measurements alone can reconstruct expression ratios without loss in precision or accuracy. We conclude that both methods are adequate options in large-scale projects where the amount of a common reference RNA pool is usually restrictive.

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The thesis comprises three essays that use experimental methods, one about other-regarding motivations in economic behavior and the others on pro-social behavior in two environmental economics problems. The first chapter studies how the expectations of the others and the concern to maintain a balance between effort exerted and rewards obtained interact in shaping the behavior in a modified dictator game. We find that dictators condition their choices on recipients' expectations only when there is a high probability that the the recipient will not be compensated for her effort. Otherwise, dictators tend to balance the efforts and rewards of the recipients, irrespective of the recipients' expectations. In the second chapter, I investigate the problem of local opposition to large public projects (e.g. landfills, incinerators, etc.). In particular, the experiment shows how the uncertainty about the project's quality makes the community living in the host site skeptical about the project. I also test whether side-transfers and costly information disclosure can help to increase the efficiency. Both tools succesfully make the host more willing to accept the project, but they lead to the realization of different types of projects. The last chapter is an experiment on climate negotiations. To avoid the global warming, countries are called to cooperate in the abatement of their emissions. We study whether the dynamic aspect of the climate change makes cooperation across countries behaviorally more difficult. We also consider inequality across countries as a possible factor that hinders international cooperation.

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Arnt van Tricht, gest. 1570, unterhielt bis in die späten 50er Jahre des 16. Jahrhunderts, wahrschein-lich aus Antwerpen kommend, in Kalkar am Niederrhein eine sehr erfolgreiche Werkstatt. Die bis dahin vorherrschende spätgotische Formensprache der langjährig ansässigen Bildhauer löste er durch die der Renaissance ab, führte jedoch deren Arbeitsfelder und Materialwahl weiter. Arnt van Tricht schuf Arbeiten sowohl religiöser als auch profaner Natur innerhalb des Gebiets der damals sehr bedeutenden Vereinigten Herzogtümer Kleve-Mark-Jülich-Berg und Geldern. Seine wohlhabenden Auftraggeber entstammten dem Klerus, der Bürgerschaft und dem Adel.rnIm Rahmen der Arbeit zeigte sich, dass sich für den Künstler die Verlegung der herzoglichen Residenz nach Düsseldorf und der wirtschaftliche Niedergang der Region letztlich stärker auswirkte als die religiösen Veränderungen durch die Reformation.rnArnt van Tricht schuf die meisten seiner religiösen Bildwerke für die Stiftskirche St. Viktor in Xanten, die durch die Bürgerschaft ausgestattete Pfarrkirche von St. Nicolai in Kalkar und umliegende Gemeinden. Einzelne Stücke sind, wohl über familiäre Verflechtungen vermittelt, in einem weiteren Radius zu finden. Van Tricht arbeitete Schnitzretabel mitsamt ihrer ornamentalen und figuralen Aus-stattung sowie Skulpturen(-gruppen) in Eichenholz. Daneben finden sich im Werk zahlreiche in Sandstein gearbeitete Skulpturen, die teilweise an Pfeilern und Portalen der Kirchen architektur-gebunden sind. Neben diesen rundplastischen Werken schuf Arnt van Tricht eine große Anzahl an steinernen Reliefarbeiten. Hierbei nehmen die überwiegend für die lokalen Kanoniker gearbeiteten Epitaphien mit biblischem Reliefbild in Ornamentrahmen den größten Teil ein.rnEin zweiter, gleichwertiger Werkkomplex, überwiegend in Sandstein gearbeitet, ist profaner Natur und fällt durch die Größe der Aufträge ins Gewicht. Arnt van Tricht war an einigen groß angelegten Modernisierungsprojekten an Stadthäusern und Kastellen des lokalen Adels beschäftigt. Für mehrere aufwendig gestaltete Fassadendekorationen arbeitete er Architekturglieder mit figürlicher Darstellung oder Ornament, Büsten und freiplastische Skulpturen. Arnt van Tricht war aber auch an der Aus-gestaltung der Innenräume beteiligt. Aufwendig skulptierte und reliefverzierte Kaminverkleidungen stehen dabei neben reduzierteren Arbeiten für offensichtlich weniger repräsentative Räume. Neben in Eichenholz gearbeiteter Vertäfelung schuf Arnt van Tricht hölzerne figurale Handtuchhalter. Diese zeigen, wie auch die Reliefbilder der Kamine, die darüber hinaus Wappen und Porträts der Bauherren aufnehmen, eine religiöse oder profane, auch antikisierende Thematik, bei der ein moralisierender Unterton mitschwingt.rnIn dieser Arbeit werden erstmals alle Werkstücke des Künstlers zusammengeführt dargestellt, so dass ein Werkkatalog mit einem Überblick über das sehr breit gefächerte Spektrum des Opus Arnt van Trichts vorliegt. Häufig durch bloße Nennung mit Arnt van Tricht in Verbindung gebrachte Arbeiten werden bewertet und die Zu- oder Abschreibung begründet. Auch können einige Stücke neu zugeschrieben werden.

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Drosophila mutants have played an important role in elucidating the physiologic function of genes. Large-scale projects have succeeded in producing mutations in a large proportion of Drosophila genes. Many mutant fly lines have also been produced through the efforts of individual laboratories over the past century. In an effort to make some of these mutants more useful to the research community, we systematically mapped a large number of mutations affecting genes in the proximal half of chromosome arm 2L to more precisely defined regions, defined by deficiency intervals, and, when possible, by individual complementation groups. To further analyze regions 36 and 39-40, we produced 11 new deficiencies with gamma irradiation, and we constructed 6 new deficiencies in region 30-33, using the DrosDel system. trans-heterozygous combinations of deficiencies revealed 5 additional functions, essential for viability or fertility.

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More than eighteen percent of the world’s population lives without reliable access to clean water, forced to walk long distances to get small amounts of contaminated surface water. Carrying heavy loads of water long distances and ingesting contaminated water can lead to long-term health problems and even death. These problems affect the most vulnerable populations, women, children, and the elderly, more than anyone else. Water access is one of the most pressing issues in development today. Boajibu, a small village in Sierra Leone, where the author served in Peace Corps for two years, lacks access to clean water. Construction of a water distribution system was halted when a civil war broke out in 1992 and has not been continued since. The community currently relies on hand-dug and borehole wells that can become dirty during the dry season, which forces people to drink contaminated water or to travel a far distance to collect clean water. This report is intended to provide a design the system as it was meant to be built. The water system design was completed based on the taps present, interviews with local community leaders, local surveying, and points taken with a GPS. The design is a gravity-fed branched water system, supplied by a natural spring on a hill adjacent to Boajibu. The system’s source is a natural spring on a hill above Boajibu, but the flow rate of the spring is unknown. There has to be enough flow from the spring over a 24-hour period to meet the demands of the users on a daily basis, or what is called providing continuous flow. If the spring has less than this amount of flow, the system must provide intermittent flow, flow that is restricted to a few hours a day. A minimum flow rate of 2.1 liters per second was found to be necessary to provide continuous flow to the users of Boajibu. If this flow is not met, intermittent flow can be provided to the users. In order to aid the construction of a distribution system in the absence of someone with formal engineering training, a table was created detailing water storage tank sizing based on possible source flow rates. A builder can interpolate using the source flow rate found to get the tank size from the table. However, any flow rate below 2.1 liters per second cannot be used in the table. In this case, the builder should size the tank such that it can take in the water that will be supplied overnight, as all the water will be drained during the day because the users will demand more than the spring can supply through the night. In the developing world, there is often a problem collecting enough money to fund large infrastructure projects, such as a water distribution system. Often there is only enough money to add only one or two loops to a water distribution system. It is helpful to know where these one or two loops can be most effectively placed in the system. Various possible loops were designated for the Boajibu water distribution system and the Adaptive Greedy Heuristic Loop Addition Selection Algorithm (AGHLASA) was used to rank the effectiveness of the possible loops to construct. Loop 1 which was furthest upstream was selected because it benefitted the most people for the least cost. While loops which were further downstream were found to be less effective because they would benefit fewer people. Further studies should be conducted on the water use habits of the people of Boajibu to more accurately predict the demands that will be placed on the system. Further population surveying should also be conducted to predict population change over time so that the appropriate capacity can be built into the system to accommodate future growth. The flow at the spring should be measured using a V-notch weir and the system adjusted accordingly. Future studies can be completed adjusting the loop ranking method so that two users who may be using the water system for different lengths of time are not counted the same and vulnerable users are weighted more heavily than more robust users.

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Free riders and holdouts are market failures that potentially impede the completion of otherwise beneficial transactions. The key difference is that the free rider problem is a demand side externality that requires taxation to compel payment for a public good, while the holdout problem is a supply side externality that requires eminent domain to force the sale of land for large scale projects. This paper highlights that distinction between these two problems and uses the resulting insights to clarify the meaning of the public use requirement of the Fifth Amendment takings clause.

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Durante los últimos años, la construcción de grandes yates ha evolucionado hacia conceptos y diseños más complejos dónde se ha priorizado en muchas ocasiones la estética arquitectónica y exigencias de confort de los armadores y operadores dejando en segundo plano aspectos clave de seguridad. Diferentes Organismos Internacionales y las Sociedades de Clasificación han venido adaptando sus requisitos a la problemática específica de este tipo de buques, tratando de compatibilizar tendencias de diseño con exigencias de resistencia, integridad estructural, estanqueidad y seguridad entre otras. En la actualidad, la construcción de grandes yates con esloras incluso por encima de los 100 metros, el aumento del número de pasajeros por encima del límite tradicional de 12, las nuevas tendencias de ahorro energético y protección medioambiental que se están implantando en la industria en general y marítima en particular, plantean una serie de desafíos tanto a los diseñadores como a las Sociedades de Clasificación que deben avanzar en sus reglamentaciones para cubrir estos y otros aspectos. Son precisamente estos aspectos medioambientales, tradicionalmente relegados en la industria de grandes yates los que están ocupando en la actualidad un primer plano en los desarrollos de normativa de diferentes Organismos Internacionales y Nacionales. El impacto que estas nuevas normativas van a tener sobre el diseño de grandes yates a motor centra el desarrollo de esta Tesis. Hasta donde ha podido conocer el doctorando, esta es la primera vez que en una Tesis Doctoral se abordan los principales mecanismos que regulan el diseño y la construcción de grandes yates a motor, se estudian y analizan las regulaciones internacionales en materia de protección medioambiental y de eficiencia energética aplicables a los yates, se seleccionan y describen un conjunto de tecnologías maduras de carácter medioambiental, susceptibles de ser empleadas en yates y se determina los parámetros y aspectos del diseño a aplicar al proyecto de grandes yates a motor como resultado de la aplicación de estas tecnologías, analizados bajo la perspectiva de la Sociedad de Clasificación y de los Organismos Internacionales. La Tesis comienza con un análisis de la industria de construcción de grandes yates, la flota existente de grandes yates, la cartera actual de pedidos y la evolución esperada del mercado. Aquí se pone de manifiesto que a pesar de la crisis económica global de los últimos años, este mercado goza relativamente de buena salud y las previsiones son favorables, particularmente para el sector en Europa. A continuación se aborda el estado del arte del diseño de yate grande, sus peculiaridades, particularmente estructurales y de armamento, que le diferencian de otros tipos de buques y las tendencias en su diseño. Se pone de manifiesto cómo el proyecto de estos yates ha evolucionado hacia yates de gran tamaño y complejidad técnica, debido a la demanda y necesidades actuales y cómo ha influido en aspectos como la disposición estructural. Seguidamente se describen los principales mecanismos que regulan el diseño y construcción de grandes yates, particularmente el Código de Grandes Yates Comerciales de la Maritime & Coastguard Agency del Reino Unido, y las Reglas y Reglamentos de la Sociedad de Clasificación Lloyd’s Register para la Clasificación de yates; por ser ambas organizaciones las que lideran el Registro y la Clasificación respectivamente de este tipo de buques, objeto del estudio. El doctorando ejerce su actividad profesional como inspector de Lloyd’s Register en una oficina técnica de apoyo y evaluación de diseño, siendo especialista en grandes yates, lo que ha permitido exponer de primera mano el punto de vista de la Sociedad de Clasificación. En el siguiente Capítulo se describen las principales reglamentaciones internacionales de carácter medioambiental que afectan al diseño, construcción y operación de los yates, algunas de las cuales, como es el caso del Convenio Internacional para el Control y la Gestión del Agua de Lastre y Sedimentos de los buques (BWM 2004) aún no ha entrado en vigor a la fecha de terminación de esta Tesis. Seguidamente se realiza una selección de tecnologías desde el punto de vista de protección medioambiental y ahorro energético y su aplicación al diseño y construcción de grandes yates. Algunas de estas tecnologías son maduras y ya habían sido utilizadas con éxito en otros tipos de buques, pero su aplicación a los yates entraña ciertos desafíos que se describen en este Capítulo. A continuación se determinan y analizan los principales parámetros de diseño de los yates grandes a motor como consecuencia de las tecnologías estudiadas y se indican una serie de aspectos de diseño bajo la perspectiva de la Sociedad de Clasificación y de los Organismos Marítimos Internacionales. Finalmente se llega a una serie de conclusiones y se identifican futuras líneas de investigación en relación a las tecnologías descritas en este trabajo. ABSTRACT In recent years, the building of large yachts has evolved into more complex concepts and designs where often prioritized architectural aesthetics and comfort requirements of owners and operators leaving in the background key security aspects. Several international organizations and classification societies have been adapting their requirements to the specific problems of this type of vessel, trying to reconcile demands design trends with resistance, structural integrity, watertightness and safety among others. At present, the building of large yachts with lengths even above 100 meters, the increase in passenger numbers over the traditional limit of 12, new trends of energy saving and environmental protection are being implemented in the marine industry in particular, they pose a number of challenges to both designers and classification societies that should update and improve their regulations to cover these and other aspects. It is precisely these environmental issues, traditionally relegated to the large yacht industry, which are currently occupying center stage in the development of rules of different international and national bodies. The impact that these new standards will have on the design of large motor yachts focuses the development of this thesis. As far as it is known, this is the first time in a doctoral thesis the main mechanisms regulating the design and construction of large motor yachts are addressed, the international regulations on environmental protection and energy efficiency requirements for yachts are studied and analyzed, a set of mature environmental technologies, capable of being applied to yachts are selected and described, the parameters and design aspects to be applied to large yacht projects as a result of the application of these technologies are determined and analyzed from the perspective of the Classification Society and international organizations. The thesis begins with an analysis of the shipbuilding industry of large yachts, the existing fleet of large yachts, the current backlog and the expected market developments. Here it becomes clear that despite the global economic crisis of recent years, this market enjoys relatively good health and prospects are favorable, particularly for the sector in Europe. Then the state of the art of large yacht design, its peculiarities, particularly structural and outfitting, that differentiate it from other types of ships and trends in design is discussed. It shows how the project of these yachts has evolved to large yachts and technical complexity, due to the demand and needs and how it has influenced the structural arrangement aspects. Then the main mechanisms regulating the design and construction of large yachts, particularly the Large Commercial Yacht Code developed by the Maritime & Coastguard Agency (UK) and the Lloyd’s Register Rules & Regulations for the Classification of Special Service Craft including yachts are described; the two organizations to be leading the registration and classification respectively of such vessels under study. The doctoral student practices his profession as a senior specialist to Lloyd’s Register in a technical support office, dealing with the design assessment of large yachts, which allowed exposing firsthand view of the Classification Society. In the next chapter describes the main international environmental regulations, affecting the design, construction and operation of yachts, some of which, such as the International Convention for the Control and Management of Ships' Ballast Water and Sediments (BWM 2004) has not yet entered into force at the date of completion of this thesis. Following is a selection of technologies from the point of view of environmental protection and energy saving and its application to design and construction of large yachts. Some of these technologies are mature and have already been used successfully in other ship types, but their application to yachts entails certain challenges that are described in this chapter. Then identifies and analyzes the main design parameters of large motor yachts as a result of the technologies studied and a number of design aspects are given from the perspective of Classification Society and international maritime organizations. Finally, a number of conclusions are exposed, and future research is identified in relation to the technologies described in this Thesis.

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The Mouse Genome Database (MGD) is the community database resource for the laboratory mouse, a key model organism for interpreting the human genome and for understanding human biology and disease (http://www.informatics.jax.org). MGD provides standard nomenclature and consensus map positions for mouse genes and genetic markers; it provides a curated set of mammalian homology records, user-defined chromosomal maps, experimental data sets and the definitive mouse ‘gene to sequence’ reference set for the research community. The integration and standardization of these data sets facilitates the transition between mouse DNA sequence, gene and phenotype annotations. A recent focus on allele and phenotype representations enhances the ability of MGD to organize and present data for exploring the relationship between genotype and phenotype. This link between the genome and the biology of the mouse is especially important as phenotype information grows from large mutagenesis projects and genotype information grows from large-scale sequencing projects.

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Most comparative studies of public policies for competitiveness focus on the links among public agencies and industrial sectors. This paper argues that the professions---or knowledge-bearing elites-that animate these organizational links are equally significant. For public policies to promote technological advance, the visions and self-images of knowledge-bearing elites are par­ ticularly important. By examining administrative and technical elites in France and Germany in the 1980s, the paper identifies characteristics that enable these elites to implement policy in some cases, but not in others. France's "state-created" elites were well-positioned to initiate and implement large technology projects, such as digitizing the telecommunications network. Germany's state-recognized elites were, by contrast, better positioned to facilitate framework­ oriented programs that aimed at the diffusion of new technologies throughout industry. The linkages among administrative and technical elites also explain why French policymakers had difficulty adapting policy to changing circumstances over time while German policymakers managed in many cases to learn more from previous policy experiences and to adapt subsequent initiatives accordingly.

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The following activities are specifically identified as ineligible. 1. Design Engineering costs of water storage tanks/towers. 2. Construction of buildings, or portions thereof, used predominantly for the general conduct of government (e.g., city halls, courthouses, jails, police stations). 3. General government expenses. 4. Costs of operating and maintaining public facilities and services (e.g., mowing parks, replacing street light bulbs). 5. Servicing or refinancing of existing debt.

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Guest editorial: This special issue has been drawn from papers that were published as part of the Second European Conference on Management of Technology (EuroMOT) which was held at Aston Business School (Birmingham, UK) 10-12 September 2006. This was the official European conference for the International Association for Management of Technology (IAMOT); the overall theme of the conference was “Technology and global integration.” There were many high-calibre papers submitted to the conference and published in the associated proceedings (Bennett et al., 2006). The streams of interest that emerged from these submissions were the importance of: technology strategy, innovation, process technologies, managing change, national policies and systems, research and development, supply chain technology, service and operational technology, education and training, small company incubation, technology transfer, virtual operations, technology in developing countries, partnership and alliance, and financing and investment. This special issue focuses upon the streams of interest that accentuate the importance of collaboration between different organisations. Such organisations vary greatly in character; for instance, they may be large or small, publicly or privately owned, and operate in manufacturing or service sectors. Despite these varying characteristics they all have something in common; they all stress the importance of inter-organisational collaboration as a critical success factor for their organisation. In today's global economy it is essential that organisations decide what their core competencies are what those of complementing organisations are. Core competences should be developed to become a bases of differentiation, leverage and competitive advantage, whilst those that are less mature should be outsourced to other organisations that can claim to have had more recognition and success in that particular core competence (Porter, 2001). This strategic trend can be observed throughout advanced economies and is growing strongly. If a posteriori reasoning is applied here it follows that organisations could continue to become more specialised in fewer areas whilst simultaneously becoming more dependent upon other organisations for critical parts of their operations. Such actions seem to fly in the face of rational business strategy and so the question must be asked: why are organisations developing this way? The answer could lie in the recent changes in endogenous and exogenous factors of the organisation; the former emphasising resource-based issues in the short-term, and strategic positioning in the long-term whilst the later emphasises transaction costs in the short-term and acquisition of new skills and knowledge in the long-term. For a harmonious balance of these forces to prevail requires organisations to firstly declare a shared meta-strategy, then to put some cross-organisational processes into place which have their routine operations automated as far as possible. A rolling business plan would review, assess and reposition each organisation within this meta-strategy according to how well they have contributed (Binder and Clegg, 2006). The important common issue here is that an increasing number of businesses today are gaining direct benefit from increasing their levels of inter-organisational collaboration. Such collaboration has largely been possible due to recent technological advances which can make organisational structures more agile (e.g. the extended or the virtual enterprise), organisational infra-structure more connected, and the sharing of real-time information an operational reality. This special issue consists of research papers that have explored the above phenomenon in some way. For instance, the role of government intervention, the use of internet-based technologies, the role of research and development organisations, the changing relationships between start-ups and established firms, the importance of cross-company communities of practice, the practice of networking, the front-loading of large-scale projects, innovation and the probabilistic uncertainties that organisations experience are explored in these papers. The cases cited in these papers are limited as they have a Eurocentric focus. However, it is hoped that readers of this special issue will gain a valuable insight into the increasing importance of collaborative practices via these studies.

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An inherent weakness in the management of large scale projects is the failure to achieve the scheduled completion date. When projects are planned with the objective of time achievement, the initial planning plays a vital role in the successful achievement of project deadlines. Cost and quality are additional priorities when such projects are being executed. This article proposes a methodology for achieving time duration of a project through risk analysis with the application of a Monte Carlo simulation technique. The methodology is demonstrated using a case application of a cross-country petroleum pipeline construction project.

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Java software or libraries can evolve via subclassing. Unfortunately, subclassing may not properly support code adaptation when there are dependencies between classes. More precisely, subclassing in collections of related classes may require reimplementation of otherwise valid classes. This problem is defined as the subclassing anomaly, which is an issue when software evolution or code reuse is a goal of the programmer who is using existing classes. Object Teams offers an implicit fix to this problem and is largely compatible with the existing JVMs. In this paper, we evaluate how well Object Teams succeeds in providing a solution for a complex, real world project. Our results indicate that while Object Teams is a suitable solution for simple examples, it does not meet the requirements for large scale projects. The reasons why Object Teams fails in certain usages may prove useful to those who create linguistic modifications in languages or those who seek new methods for code adaptation.

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Date of Acceptance: 08/05/2015 Date of online publication: 16/05/2015 Elemental and isotopic data, thin and polished sections used in this contribution were obtained through two large umbrella-projects with grants provided by the Norwegian Research Council grant 191530/V30 to VAM and NERC grant NE/G00398X/1 to AEF. We thank A. Črne, the editor A. Strasser as well as one anonymous reviewer and D. Papineau for providing their valuable criticism and suggestions.

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The atmospheric seasonal cycle of the North Atlantic region is dominated by meridional movements of the circulation systems: from the tropics, where the West African Monsoon and extreme tropical weather events take place, to the extratropics, where the circulation is dominated by seasonal changes in the jetstream and extratropical cyclones. Climate variability over the North Atlantic is controlled by various mechanisms. Atmospheric internal variability plays a crucial role in the mid-latitudes. However, El Niño-Southern Oscillation (ENSO) is still the main source of predictability in this region situated far away from the Pacific. Although the ENSO influence over tropical and extra-tropical areas is related to different physical mechanisms, in both regions this teleconnection seems to be non-stationary in time and modulated by multidecadal changes of the mean flow. Nowadays, long observational records (greater than 100 years) and modeling projects (e.g., CMIP) permit detecting non-stationarities in the influence of ENSO over the Atlantic basin, and further analyzing its potential mechanisms. The present article reviews the ENSO influence over the Atlantic region, paying special attention to the stability of this teleconnection over time and the possible modulators. Evidence is given that the ENSO–Atlantic teleconnection is weak over the North Atlantic. In this regard, the multidecadal ocean variability seems to modulate the presence of teleconnections, which can lead to important impacts of ENSO and to open windows of opportunity for seasonal predictability.