948 resultados para Curwood, James Oliver, 1878-1927


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Microphilypnus Myers, 1927 is a genus with three nominal species (M. amazonicus and M. macrostoma from the lower Amazon basin, and M. ternetzi from Orinoco), and is among the most poorly studied groups of Neotropical fishes. In this paper, M. ternetzi and M. macrostoma are redescribed and validated and M. amazonicus is regarded as synonym of M. ternetzi. Also, a new species, M. acangaquara, is described from the lower Amazon.

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We report an improved measurement of (nu) over bar (mu) disappearance over a distance of 735 km using the MINOS detectors and the Fermilab Main Injector neutrino beam in a (nu) over bar (mu)-enhanced configuration. From a total exposure of 2.95 x 10(20) protons on target, of which 42% have not been previously analyzed, we make the most precise measurement of Delta(m) over bar (2) = [2.62(-0.28)(+0.31)(stat) +/- 0.09(syst)] x 10(-3) eV(2) and constrain the (nu) over bar (mu) mixing angle sin(2)(2 (theta) over bar) > 0.75 (90% C.L.). These values are in agreement with Delta m(2) and sin(2)(2 theta) measured for nu(mu), removing the tension reported in [P. Adamson et al. (MINOS), Phys. Rev. Lett. 107, 021801 (2011).].

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We have searched for sidereal variations in the rate of antineutrino interactions in the MINOS Near Detector. Using antineutrinos produced by the NuMI beam, we find no statistically significant sidereal modulation in the rate. When this result is placed in the context of the Standard Model Extension theory we are able to place upper limits on the coefficients defining the theory. These limits are used in combination with the results from an earlier analysis of MINOS neutrino data to further constrain the coefficients.

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This paper reports measurements of atmospheric neutrino and antineutrino interactions in the MINOS Far Detector, based on 2553 live-days (37.9 kton-years) of data. A total of 2072 candidate events are observed. These are separated into 905 contained-vertex muons and 466 neutrino-induced rock-muons, both produced by charged-current nu(mu) and (nu) over bar (mu) interactions, and 701 contained-vertex showers, composed mainly of charged-current nu(e) and (nu) over bar (e) interactions and neutral-current interactions. The curvature of muon tracks in the magnetic field of the MINOS Far Detector is used to select separate samples of nu(mu) and (nu) over bar (mu) events. The observed ratio of (nu) over bar (mu) to v(mu) events is compared with the Monte Carlo ( MC) simulation, giving a double ratio of R((nu) over bar/nu)data/R(nu) over bar/nu MC = 1.03 +/- 0.08(stat) +/- 0.08(syst). The v(mu) and (nu) over bar (mu) data are separated into bins of L/E resolution, based on the reconstructed energy and direction of each event, and a maximum likelihood fit to the observed L/E distributions is used to determine the atmospheric neutrino oscillation parameters. This fit returns 90% confidence limits of |Delta m(2)| = (1.9 +/- 0.4) x 10(-3) eV(2) and sin(2)2 theta > 0.86. The fit is extended to incorporate separate nu(mu) and (nu) over bar mu oscillation parameters, returning 90% confidence limits of |Delta m(2)| - |Delta(m) over bar (2)| = 0.6(-0.8)(+2.4) x 10(-3) eV(2) on the difference between the squared-mass splittings for neutrinos and antineutrinos.

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Por meio do exame do conto "Os amigos dos amigos" ("The friends of the friends"), de Henry James, bem como de seu processo de criação, este trabalho investiga a categoria do duplo confrontando as suas fontes primitivas com sua adoção na narrativa moderna - um confronto que nos permite sugerir uma chave de interpretação para a ficção jamesiana, e ainda discutir a presença do sobrenatural numa sociedade que privilegia o espetáculo, a publicidade, a novidade, o consumo e o progresso.

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Este artigo reavalia o "modelo simplificado" da Teoria Geral de Keynes elaborado por James Meade e procura complementar alguns dos argumentos teóricos que Meade deixou apenas indicados. O artigo também responde às solicitações de Frisch a Meade, quanto à explicação do significado de estabilidade e à explicitação dos pressupostos que garantem suas conclusões. Além disso, apresenta alguns dos cálculos não desenvolvidos por Meade, e, quando necessário, suas devidas correções.

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Introduction 1.1 Occurrence of polycyclic aromatic hydrocarbons (PAH) in the environment Worldwide industrial and agricultural developments have released a large number of natural and synthetic hazardous compounds into the environment due to careless waste disposal, illegal waste dumping and accidental spills. As a result, there are numerous sites in the world that require cleanup of soils and groundwater. Polycyclic aromatic hydrocarbons (PAHs) are one of the major groups of these contaminants (Da Silva et al., 2003). PAHs constitute a diverse class of organic compounds consisting of two or more aromatic rings with various structural configurations (Prabhu and Phale, 2003). Being a derivative of benzene, PAHs are thermodynamically stable. In addition, these chemicals tend to adhere to particle surfaces, such as soils, because of their low water solubility and strong hydrophobicity, and this results in greater persistence under natural conditions. This persistence coupled with their potential carcinogenicity makes PAHs problematic environmental contaminants (Cerniglia, 1992; Sutherland, 1992). PAHs are widely found in high concentrations at many industrial sites, particularly those associated with petroleum, gas production and wood preserving industries (Wilson and Jones, 1993). 1.2 Remediation technologies Conventional techniques used for the remediation of soil polluted with organic contaminants include excavation of the contaminated soil and disposal to a landfill or capping - containment - of the contaminated areas of a site. These methods have some drawbacks. The first method simply moves the contamination elsewhere and may create significant risks in the excavation, handling and transport of hazardous material. Additionally, it is very difficult and increasingly expensive to find new landfill sites for the final disposal of the material. The cap and containment method is only an interim solution since the contamination remains on site, requiring monitoring and maintenance of the isolation barriers long into the future, with all the associated costs and potential liability. A better approach than these traditional methods is to completely destroy the pollutants, if possible, or transform them into harmless substances. Some technologies that have been used are high-temperature incineration and various types of chemical decomposition (for example, base-catalyzed dechlorination, UV oxidation). However, these methods have significant disadvantages, principally their technological complexity, high cost , and the lack of public acceptance. Bioremediation, on the contrast, is a promising option for the complete removal and destruction of contaminants. 1.3 Bioremediation of PAH contaminated soil & groundwater Bioremediation is the use of living organisms, primarily microorganisms, to degrade or detoxify hazardous wastes into harmless substances such as carbon dioxide, water and cell biomass Most PAHs are biodegradable unter natural conditions (Da Silva et al., 2003; Meysami and Baheri, 2003) and bioremediation for cleanup of PAH wastes has been extensively studied at both laboratory and commercial levels- It has been implemented at a number of contaminated sites, including the cleanup of the Exxon Valdez oil spill in Prince William Sound, Alaska in 1989, the Mega Borg spill off the Texas coast in 1990 and the Burgan Oil Field, Kuwait in 1994 (Purwaningsih, 2002). Different strategies for PAH bioremediation, such as in situ , ex situ or on site bioremediation were developed in recent years. In situ bioremediation is a technique that is applied to soil and groundwater at the site without removing the contaminated soil or groundwater, based on the provision of optimum conditions for microbiological contaminant breakdown.. Ex situ bioremediation of PAHs, on the other hand, is a technique applied to soil and groundwater which has been removed from the site via excavation (soil) or pumping (water). Hazardous contaminants are converted in controlled bioreactors into harmless compounds in an efficient manner. 1.4 Bioavailability of PAH in the subsurface Frequently, PAH contamination in the environment is occurs as contaminants that are sorbed onto soilparticles rather than in phase (NAPL, non aqueous phase liquids). It is known that the biodegradation rate of most PAHs sorbed onto soil is far lower than rates measured in solution cultures of microorganisms with pure solid pollutants (Alexander and Scow, 1989; Hamaker, 1972). It is generally believed that only that fraction of PAHs dissolved in the solution can be metabolized by microorganisms in soil. The amount of contaminant that can be readily taken up and degraded by microorganisms is defined as bioavailability (Bosma et al., 1997; Maier, 2000). Two phenomena have been suggested to cause the low bioavailability of PAHs in soil (Danielsson, 2000). The first one is strong adsorption of the contaminants to the soil constituents which then leads to very slow release rates of contaminants to the aqueous phase. Sorption is often well correlated with soil organic matter content (Means, 1980) and significantly reduces biodegradation (Manilal and Alexander, 1991). The second phenomenon is slow mass transfer of pollutants, such as pore diffusion in the soil aggregates or diffusion in the organic matter in the soil. The complex set of these physical, chemical and biological processes is schematically illustrated in Figure 1. As shown in Figure 1, biodegradation processes are taking place in the soil solution while diffusion processes occur in the narrow pores in and between soil aggregates (Danielsson, 2000). Seemingly contradictory studies can be found in the literature that indicate the rate and final extent of metabolism may be either lower or higher for sorbed PAHs by soil than those for pure PAHs (Van Loosdrecht et al., 1990). These contrasting results demonstrate that the bioavailability of organic contaminants sorbed onto soil is far from being well understood. Besides bioavailability, there are several other factors influencing the rate and extent of biodegradation of PAHs in soil including microbial population characteristics, physical and chemical properties of PAHs and environmental factors (temperature, moisture, pH, degree of contamination). Figure 1: Schematic diagram showing possible rate-limiting processes during bioremediation of hydrophobic organic contaminants in a contaminated soil-water system (not to scale) (Danielsson, 2000). 1.5 Increasing the bioavailability of PAH in soil Attempts to improve the biodegradation of PAHs in soil by increasing their bioavailability include the use of surfactants , solvents or solubility enhancers.. However, introduction of synthetic surfactant may result in the addition of one more pollutant. (Wang and Brusseau, 1993).A study conducted by Mulder et al. showed that the introduction of hydropropyl-ß-cyclodextrin (HPCD), a well-known PAH solubility enhancer, significantly increased the solubilization of PAHs although it did not improve the biodegradation rate of PAHs (Mulder et al., 1998), indicating that further research is required in order to develop a feasible and efficient remediation method. Enhancing the extent of PAHs mass transfer from the soil phase to the liquid might prove an efficient and environmentally low-risk alternative way of addressing the problem of slow PAH biodegradation in soil.

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Die James Bond-Filme: seit über 40 Jahren sind sie ein unübersehbarer Bestandteil der Populärkultur. Anfang der 60er Jahre unter völlig anderen historischen, sozialen und nicht zuletzt filmtechnischen Voraussetzungen aus der Taufe gehoben, gelingt es ihnen auch heute noch, ein Massenpublikum für sich zu gewinnen. Inwiefern kann man bei einer so langen Laufzeit überhaupt noch von einer homogenen Serie sprechen? Und was für Gemeinsamkeiten, Unterschiede und auch Weiterentwicklungen von der ursprünglichen Machart sind hier zu beobachten? Dies sind die Grundfragen der vorliegenden Dissertation. Bei der Benennung der seriellen Eigenschaften werden sowohl inhaltliche als auch dramaturgische und filmtechnisch-formale Aspekte betrachtet. Die Figurenkonstellation von Held, Gegenspieler und der weiblichen Hauptfigur, die zwischen den beiden steht und häufig die Seiten wechselt, ist ein Schema das - kaum variiert - schon in den Romanvorlagen Ian Flemings zum Einsatz kam und auch das Rückgrat der Film-Plots bildet. Dennoch ließ dieses Gerüst den mittlerweile fünf verschiedenen Darstellern, die James Bond nacheinander verkörperten, genügend Freiraum für das Ausarbeiten eines eigenen Rollenkonzepts, das auf ihren speziellen Schauspielstil ausgerichtet war. Dadurch erhielt die James Bond-Figur jeweils eine Neuinterpretation, die sich insbesondere in ihrem sozialen Habitus bemerkbar macht, der je nach Darsteller zwischen provokantem Aufsteigertyp und aristokratischem Gentleman changierte. Zum unverwechselbaren Erkennungsmerkmal der Bond-Serie avancierte die so genannte 'gun-barrel'-Sequenz, die in den ersten Sekunden jedes Films abläuft. Auch die sich anschließende Vortitelsequenz, eine auf Spannung oder Action angelegte Szene, die einen Vorgeschmack auf den folgenden Film liefern soll, ist ein Element, das der Machart von Fernsehserien entnommen ist. Neben diesen bewusst eingesetzten Markenzeichen lässt sich auch in der Gestaltungsweise der Filme - in Kameraführung, Schnitt, Musik und Set Design - eine stilistische Kontinuität feststellen, die insbesondere dadurch bedingt ist, dass die Serie seit jeher von den Produzenten ähnlich wie ein Familienunternehmen geführt wurde und - zumindest bis Ende der 80er Jahre - auch die kreativen Köpfe der Filme konsequent im eigenen Team ausgebildet wurden.

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Questa tesi è un tentativo di analizzare il percorso artistico di Etta James, prendendo in considerazione le varie influenze che hanno contribuito a formare la sua personalità artistica a livello canoro ed interpretativo. Si parte da uno spaccato sull’importanza del gospel come genere propedeutico ad un’interpretazione efficace per l’artista afroamericano. Successivamente si passa all’immagine che Etta James si costruisce per sé e come questa influenza la sua vita, quali sono le canzoni che non le paiono in linea con la sua immagine e come mentre tenta di districarsi attraverso diversi altri generi, come blues, rock, funk. Poi viene analizzata la figura della madre biologica di James e come questa venga collegata indissolubilmente alla figura di Billie Holiday, e come trovare la maturità di affrontare quest’ultima farà in modo che anche il rapporto con la figura materna cambi. Viene analizzato uno dei più grandi successi della cantante, “At Last”, di cui lei è interprete ma non autrice, ma attraverso una grande abilità stilistica riesce a formare quello che sarà uno standard per gli artisti contemporanei. Ed infine si tirano le somme guardando al retaggio artistico che ha lasciato dietro di sé l’artista.