954 resultados para Djuna Barnes


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Characteristics of shiftwork schedules have implications for off-shift well-being. We examined the extent to which several shift characteristics (e.g., shift length, working sundays) are associated with three aspects of off-shift well-being: work-to-family conflict, physical well-being, and mental wellbeing. We also investigated whether these relationships differed in four nations. The Survey of Work and Time was completed by 906 healthcare professionals located in Australia, Brazil, Croatia, and the USA. Hierarchical multiple regression analyses supported the hypothesis that shiftwork characteristics account for significant unique variance in all three measures of well-being beyond that accounted for by work and family demands and personal characteristics. The patterns of regression weights indicated that particular shiftwork characteristics have differential relevance to indices of work-to-family conflict, physical well-being, and mental well-being. Our findings suggest that healthcare organizations should carefully consider the implications of shiftwork characteristics for off-shift well-being. Furthermore, although our findings did not indicate national differences in the nature of relationships between shift characteristics and well-being, shiftwork characteristics and demographics for healthcare professionals differ in systematic ways among nations; as such, effective solutions may be context-specific. (c) 2008 Elsevier Ltd. All rights reserved.

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The search for rocky exoplanets plays an important role in our quest for extra-terrestrial life. Here, we discuss the extreme physical properties possible for the first characterised rocky super-Earth, CoRoT-7b (R(pl) = 1.58 +/- 0.10 R(Earth), M(pl) = 6.9 +/- 1.2 M(Earth)). It is extremely close to its star (a = 0.0171 AU = 4.48 R(st)), with its spin and orbital rotation likely synchronised. The comparison of its location in the (M(pl), R(pl)) plane with the predictions of planetary models for different compositions points to an Earth-like composition, even if the error bars of the measured quantities and the partial degeneracy of the models prevent a definitive conclusion. The proximity to its star provides an additional constraint on the model. It implies a high extreme-UV flux and particle wind, and the corresponding efficient erosion of the planetary atmosphere especially for volatile species including water. Consequently, we make the working hypothesis that the planet is rocky with no volatiles in its atmosphere, and derive the physical properties that result. As a consequence, the atmosphere is made of rocky vapours with a very low pressure (P <= 1.5 Pa), no cloud can be sustained, and no thermalisation of the planet is expected. The dayside is very hot (2474 +/- 71 K at the sub-stellar point) while the nightside is very cold (50-75 K). The sub-stellar point is as hot as the tungsten filament of an incandescent bulb, resulting in the melting and distillation of silicate rocks and the formation of a lava ocean. These possible features of CoRoT-7b could be common to many small and hot planets, including the recently discovered Kepler-10b. They define a new class of objects that we propose to name ""Lava-ocean planets"". (C) 2011 Elsevier Inc. All rights reserved.

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The rate of high energy cosmic ray muons as measured underground is shown to be strongly correlated with upper-air temperatures during short-term atmospheric (10-day) events. The effects are seen by correlating data from the MINOS underground detector and temperatures from the European Centre for Medium Range Weather Forecasts during the winter periods from 2003-2007. This effect provides an independent technique for the measurement of meteorological conditions and presents a unique opportunity to measure both short and long-term changes in this important part of the atmosphere. Citation: Osprey, S., et al. (2009), Sudden stratospheric warmings seen in MINOS deep underground muon data, Geophys. Res. Lett., 36, L05809, doi: 10.1029/2008GL036359.

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The Main Injector Neutrino Oscillation Search (MINOS) experiment uses an accelerator-produced neutrino beam to perform precision measurements of the neutrino oscillation parameters in the ""atmospheric neutrino"" sector associated with muon neutrino disappearance. This long-baseline experiment measures neutrino interactions in Fermilab`s NuMI neutrino beam with a near detector at Fermilab and again 735 km downstream with a far detector in the Soudan Underground Laboratory in northern Minnesota. The two detectors are magnetized steel-scintillator tracking calorimeters. They are designed to be as similar as possible in order to ensure that differences in detector response have minimal impact on the comparisons of event rates, energy spectra and topologies that are essential to MINOS measurements of oscillation parameters. The design, construction, calibration and performance of the far and near detectors are described in this paper. (C) 2008 Elsevier B.V. All rights reserved.

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We present the first measurement of photoproduction of J/psi and of two-photon production of high-mass e(+)e(-) pairs in electromagnetic (or ultra-peripheral) nucleus-nucleus interactions, using Au + Au data at root s(NN) = 200 GeV. The events are tagged with forward neutrons emitted following Coulomb excitation of one or both Au* nuclei. The event sample consists of 28 events with m(e+e-) > 2 GeV/c(2) with zero like-sign background. The measured cross sections at midrapidity of d sigma/dy (J/psi + Xn, y = 0) = 76 +/- 33 (stat) +/- 11 (syst) pb and d(2)sigma /dm dy (e(+) e(-) + Xn, y = 0) = 86 +/- 23(stat) +/- 16(syst) mu b/ (GeV/c(2)) for m(e+e-) epsilon vertical bar 2.0, 2.8 vertical bar GeV/c(2) have been compared and found to be consistent with models for photoproduction of J/psi and QED based calculations of two-photon production of e(+)e(-) pairs. (C) 2009 Elsevier B.V. All rights reserved.

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PHENIX has measured the electron-positron pair mass spectrum from 0 to 8 GeV/c(2) in p + p collisions at root s = 200 GeV. The contributions from light meson decays to e(+)e(-) pairs have been determined based on measurements of hadron production cross sections by PHENIX. Within the systematic uncertainty of similar to 20% they account for all e(+)e(-) pairs in the mass region below similar to 1 GeV/c(2). The e(+)e(-) pair yield remaining after subtracting these contributions is dominated by semileptonic decays of charmed hadrons correlated through flavor conservation. Using the spectral shape predicted by PYTHIA, we estimate the charm production cross section to be 544 +/- 39(stat) +/- 142(syst) +/- 200(model) pb. which is consistent with QCD calculations and measurements of single leptons by PHENIX. (C) 2008 Elsevier BV. All rights reserved.

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Components of the DNA mismatch repair (MMR) pathway are major players in processes known to generate genetic diversity, such as mutagenesis and DNA recombination. Trypanosoma cruzi, the protozoan parasite that causes Chagas disease has a highly heterogeneous population, composed of a pool of strains with distinct characteristics. Studies with a number of molecular markers identified up to six groups in the T. cruzi population, which showed distinct levels of genetic variability. To investigate the molecular basis for such differences, we analyzed the T. cruzi MSH2 gene, which encodes a key component of MMR, and showed the existence of distinct isoforms of this protein. Here we compared cell survival rates after exposure to genotoxic agents and levels of oxidative stress-induced DNA in different parasite strains. Analyses of msh2 mutants in both T. cruzi and T. brucei were also used to investigate the role of Tcmsh2 in the response to various DNA damaging agents. The results suggest that the distinct MSH2 isoforms have differences in their activity. More importantly, they also indicate that, in addition to its role in MMR, TcMSH2 acts in the parasite response to oxidative stress through a novel mitochondrial function that may be conserved in T. brucei. (C) 2010 Elsevier B.V. All rights reserved.

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Fet-Mats är den gruvdräng som omkom och försvann i en rasolycka i Falu koppargruva under 1670-talet och vars kropp upptäcktes välbevarad, med fortfarande ungdomligt utseende, mer än fyra årtionden senare 1719. Han igenkändes då av sin trolovade - nu en gammal gumma. På grund av den märkligt bibehållna kroppen och det hisnande ögonblick då den åldrade kvinnan återsåg sin ungdoms kärlek, blev Fet-Mats och hans historia snabbt känd, även internationellt. Den spreds under 1800- och 1900-talen i Europa som novell och poesi, dramatik och opera. Även idag berättas historien om Fet-Mats både utomlands och i Sverige. Intresset för historien är rentav i växande. Orsaken härtill är omdaningen under senare år av Falu gruva från storindustri till musealt världsarv, från malmbrytning till turistorienterad upplevelseindustri. Fet-Mats-berättelsen bildar centrum i denna upplevelseindustri. I mitt paper diskuteras detta förhållande samt den nutida Fet-Mats-epikens karakteristika i ett semiotiskt, narratologiskt och tematiskt perspektiv. Jag finner bl.a. att Fet-Mats-berättandet idag, på ett annat sätt än tidigare, äger en flermedial karaktär och formulerar det postmoderna tillståndets centrala tematik: representationens kris. Jag fokuserar särskilt på två berättelser med anknytning till Fet-Mats-motivet: Julian Barnes historiografiska metafiktion The Story of Mats Israelson (2004) och det dramadokumentära seriealbumet Fet-Mats: en gruvdrängs hemska öde (2005).

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Borders, the bookstore, provides us with an instructive case study regarding our collective futures. While Amazon and Barnes & Noble made changes that both streamlined and changed their services, Borders followed the “business as usual” model. That led to Chapter 11, the closing of nearly a third of their stores, and a complete restructuring of all that’s left. Not many industry analysts think even this will be enough to keep the company afloat.

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Trata das dificuldades de se avaliar uma empresa virtual com as tradicionais ferramentas de avaliação de empresas devido às suas características únicas . Compara o valor da Amazon books, a maior livraria atualmente na internet, com a Barnes and Nobles, maior revendedor de livros mundial, usando o método de fluxo de caixa descontado. Aborda algumas técnicas utilizadas para se avaliar uma empresa virtual

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Com o rápido crescimento da Internet, a quantidade de informações disponíveis tornou-se gigantesca, dificultando a busca pelo que realmente é essencial. Da mesma forma que vários esforços na divulgação de informações relevantes foram efetuados, sites de qualidade duvidosa também apareceram. Os "Sites de busca, apesar de ainda limitados, passaram a ter papel cada vez mais importante, e alguns deles são, hoje, líderes em número de acessos. A avaliação da qualidade de sites na Internet é, hoje, tópico de estudo de vários pesquisadores em todo o mundo. Vários modelos de avaliação existem, com focos que se alternam entre a avaliação dos aspectos tecnológicos e a medição da qualidade percebida pelo usuário ou consumidor. Nesta pesquisa, optou-se por analisar a aplicabilidade do instrumento "WebOual" - criado pelos professores Stuart Barnes (Victoria University of Wellington - Nova Zelândia) e Richard Vidgen (Universidade de Bath - Inglaterra) - o qual privilegia a avaliação da qualidade dos sites pesquisados pela ótica do usuário ou consumidor. Será aplicada a abordagem WebOual a três sites de busca internacionais que possuem versões localizadas em português. no Brasil: Altavista, Yahoo! e Google. Trata-se de utilização inédita da abordagem WebOual, anteriormente testada por seus criadores na avaliação de sites de Livrarias Virtuais, Universidades, Leilões ontine e sites WAP.

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The work described in this thesis aims to support the distributed design of integrated systems and considers specifically the need for collaborative interaction among designers. Particular emphasis was given to issues which were only marginally considered in previous approaches, such as the abstraction of the distribution of design automation resources over the network, the possibility of both synchronous and asynchronous interaction among designers and the support for extensible design data models. Such issues demand a rather complex software infrastructure, as possible solutions must encompass a wide range of software modules: from user interfaces to middleware to databases. To build such structure, several engineering techniques were employed and some original solutions were devised. The core of the proposed solution is based in the joint application of two homonymic technologies: CAD Frameworks and object-oriented frameworks. The former concept was coined in the late 80's within the electronic design automation community and comprehends a layered software environment which aims to support CAD tool developers, CAD administrators/integrators and designers. The latter, developed during the last decade by the software engineering community, is a software architecture model to build extensible and reusable object-oriented software subsystems. In this work, we proposed to create an object-oriented framework which includes extensible sets of design data primitives and design tool building blocks. Such object-oriented framework is included within a CAD Framework, where it plays important roles on typical CAD Framework services such as design data representation and management, versioning, user interfaces, design management and tool integration. The implemented CAD Framework - named Cave2 - followed the classical layered architecture presented by Barnes, Harrison, Newton and Spickelmier, but the possibilities granted by the use of the object-oriented framework foundations allowed a series of improvements which were not available in previous approaches: - object-oriented frameworks are extensible by design, thus this should be also true regarding the implemented sets of design data primitives and design tool building blocks. This means that both the design representation model and the software modules dealing with it can be upgraded or adapted to a particular design methodology, and that such extensions and adaptations will still inherit the architectural and functional aspects implemented in the object-oriented framework foundation; - the design semantics and the design visualization are both part of the object-oriented framework, but in clearly separated models. This allows for different visualization strategies for a given design data set, which gives collaborating parties the flexibility to choose individual visualization settings; - the control of the consistency between semantics and visualization - a particularly important issue in a design environment with multiple views of a single design - is also included in the foundations of the object-oriented framework. Such mechanism is generic enough to be also used by further extensions of the design data model, as it is based on the inversion of control between view and semantics. The view receives the user input and propagates such event to the semantic model, which evaluates if a state change is possible. If positive, it triggers the change of state of both semantics and view. Our approach took advantage of such inversion of control and included an layer between semantics and view to take into account the possibility of multi-view consistency; - to optimize the consistency control mechanism between views and semantics, we propose an event-based approach that captures each discrete interaction of a designer with his/her respective design views. The information about each interaction is encapsulated inside an event object, which may be propagated to the design semantics - and thus to other possible views - according to the consistency policy which is being used. Furthermore, the use of event pools allows for a late synchronization between view and semantics in case of unavailability of a network connection between them; - the use of proxy objects raised significantly the abstraction of the integration of design automation resources, as either remote or local tools and services are accessed through method calls in a local object. The connection to remote tools and services using a look-up protocol also abstracted completely the network location of such resources, allowing for resource addition and removal during runtime; - the implemented CAD Framework is completely based on Java technology, so it relies on the Java Virtual Machine as the layer which grants the independence between the CAD Framework and the operating system. All such improvements contributed to a higher abstraction on the distribution of design automation resources and also introduced a new paradigm for the remote interaction between designers. The resulting CAD Framework is able to support fine-grained collaboration based on events, so every single design update performed by a designer can be propagated to the rest of the design team regardless of their location in the distributed environment. This can increase the group awareness and allow a richer transfer of experiences among them, improving significantly the collaboration potential when compared to previously proposed file-based or record-based approaches. Three different case studies were conducted to validate the proposed approach, each one focusing one a subset of the contributions of this thesis. The first one uses the proxy-based resource distribution architecture to implement a prototyping platform using reconfigurable hardware modules. The second one extends the foundations of the implemented object-oriented framework to support interface-based design. Such extensions - design representation primitives and tool blocks - are used to implement a design entry tool named IBlaDe, which allows the collaborative creation of functional and structural models of integrated systems. The third case study regards the possibility of integration of multimedia metadata to the design data model. Such possibility is explored in the frame of an online educational and training platform.

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Pythagoras was one of the most important pre-Socratic thinkers, and the movement he founded, Pythagoreanism, influenced a whole thought later in religion and science. Iamblichus, an important Neoplatonic and Neopythagorean philosopher of the third century AD, produced one of the most important biographies of Pythagoras in his work Life of Pythagoras. In it he portrays the life of Pythagoras and provides information on Pythagoreanism, such as the Pythagorean religious community which resembled the cult of mysteries; the Pythagorean involvement in political affairs and in the government in southern Italy, the use of music by the Pythagoreans (means of purification of healing, use of theoretical study), the Pythagorean ethic (Pythagorean friendship and loyalty, temperance, self-control, inner balance); justice; and the attack on the Pythagoreans. Also in this biography, Iamblichus, almost seven hundred years after the termination of the Pythagorean School, established a catalog list with the names of two hundred and eighteen men and sixteen women, supposedly Pythagoreans of different nationalities. Based on this biography, a question was raised: to what extent and in what ways, can the Pythagoreans quoted by Iamblichus really be classified as Pythagoreans? We will take as guiding elements to search for answers to our central problem the following general objectives: to identify, whenever possible, which of the men and women listed in the Iamblichus catalog may be deemed Pythagorean and specific; (a) to describe the mystery religions; (b) to reflect on the similarities between the cult of mysteries and the Pythagorean School; (c) to develop criteria to define what is being a Pythagorean; (d) to define a Pythagorean; (e) to identify, if possible, through names, places of birth, life, thoughts, work, lifestyle, generation, etc.., each of the men and women listed by Iamblichus; (f) to highlight who, in the catalog, could really be considered Pythagorean, or adjusting to one or more criteria established in c, or also to the provisions of item d. To realize these goals, we conducted a literature review based on ancient sources that discuss the Pythagoreanism, especially Iamblichus (1986), Plato (2000), Aristotle (2009), as well as modern scholars of the Pythagorean movement, Cameron (1938), Burnet (1955), Burkert (1972), Barnes (1997), Gorman (n.d.), Guthrie (1988), Khan (1999), Mattéi (2000), Kirk, Raven and Shofield (2005), Fossa and Gorman (n.d.) (2010). The results of our survey show that, despite little or no availability of information on the names of alleged Pythagoreans listed by Iamblichus, if we apply the criteria and the definition set by us of what comes to be a Pythagorean to some names for which we have evidence, it is possible to assume that Iamblichus produced a list which included some Pythagoreans