942 resultados para Global Dynamics


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Through the processes of the biological pump, carbon is exported to the deep ocean in the form of dissolved and particulate organic matter. There are several ways by which downward export fluxes can be estimated. The great attraction of the 234Th technique is that its fundamental operation allows a downward flux rate to be determined from a single water column profile of thorium coupled to an estimate of POC/234Th ratio in sinking matter. We present a database of 723 estimates of organic carbon export from the surface ocean derived from the 234Th technique. Data were collected from tables in papers published between 1985 and 2013 only. We also present sampling dates, publication dates and sampling areas. Most of the open ocean Longhurst provinces are represented by several measurements. However, the Western Pacific, the Atlantic Arctic, South Pacific and the South Indian Ocean are not well represented. There is a variety of integration depths ranging from surface to 220m. Globally the fluxes ranged from -22 to 125 mmol of C/m**2/d. We believe that this database is important for providing new global estimate of the magnitude of the biological carbon pump.

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Thesis (Ph.D.)--University of Washington, 2016-06

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Thesis (Ph.D.)--University of Washington, 2016-06

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In this article I critically examine the theoretical and empirical relationship between world society, whereby global civil society is taken to be its physical or empirical counterpart, and the society of states. This relationship is typically portrayed as contradictory or confrontational, and I contend that this mainstream perspective is reliant on a superficial analysis of the relationship. If one examines the deeper dynamics, viewed in their contemporary international normative context, then one can identify the more constructive and permissive aspects of the relationship. Rather than being wholly incompatible I argue that world society and international society are mutually constitutive and mutually dependent regimes, whose relationship is more often marked by cooperation than by conflict. English School theory provides the conceptual framework for this analysis. The relationship between international and world society presents a core ontological tension within this theory, and again they tend to occupy polarised positions. A synthesis of four international theories - pluralist international society theory, solidarist international society theory, critical international theory, and the discourse of global civil society - informs the hypothesis that the relationship can be normatively and empirically reconciled. In order to empirically support this explanation I analyse two phenomena in world politics - transnational advocacy networks and humanitarian intervention - where there is an apparent tension between international and world society.

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This paper presents a review of modelling and control of biological nutrient removal (BNR)-activated sludge processes for wastewater treatment using distributed parameter models described by partial differential equations (PDE). Numerical methods for solution to the BNR-activated sludge process dynamics are reviewed and these include method of lines, global orthogonal collocation and orthogonal collocation on finite elements. Fundamental techniques and conceptual advances of the distributed parameter approach to the dynamics and control of activated sludge processes are briefly described. A critical analysis on the advantages of the distributed parameter approach over the conventional modelling strategy in this paper shows that the activated sludge process is more adequately described by the former and the method is recommended for application to the wastewater industry (c) 2006 Elsevier Ltd. All rights reserved.

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Wolbachia bacteria are common intracellular symbionts of arthropods and have been extensively studied in Drosophila. Most research focuses on two Old Word hosts, Drosophila melanogaster and Drosophila simulans, and does not take into account that some of the Wolbachia associations in these species may have evolved only after their fast global expansion and after the exposure to Wolbachia of previously isolated habitats. Here we looked at Wolbachia of Neotropical Drosophila species. Seventy-one lines of 16 Neotropical Drosophild species sampled in different regions and at different time points were analyzed. Wolbachia is absent in lines of Drosophild willistoni collected before the 1970s, but more recent samples are infected with a strain designated wWiL Wolbachia is absent in all other species of the willistoni group. Polymorphic wWil-related strains were detected in some saltans group species, with D. septentriosaltans being coinfected with at least four variants. Based on wsp and ftsZ sequence data, wWil of D. willistoni is identical to wAu, a strain isolated from D. simulans, but can be discriminated when using a polymorphic minisatellite marker. In contrast to wAu, which infects both germ line and somatic tissues of D. simulans, wWil is found exclusively in the primordial germ line cells of D. willistoni embryos. We report on a pool of closely related Wolbachia strains in Neotropical Drosophila species as a potential source for the wAu strain in D. simulans. Possible evolutionary scenarios reconstructing the infection history of wAu-like Wolbachia in Neotropical Drosophild species and the Old World species D. simulans are discussed.

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We present results of our wide-field redshift survey of galaxies in a 285 square degree region of the Shapley Supercluster (SSC), based on a set of 10 529 velocity measurements (including 1201 new ones) on 8632 galaxies obtained from various telescopes and from the literature. Our data reveal that the main plane of the SSC (v approximate to 14 500 km s(-1)) extends further than previous estimates, filling the whole extent of our survey region of 12 degrees by 30 degrees on the sky (30 x 75 h(-1) Mpc). There is also a connecting structure associated with the slightly nearer Abell 3571 cluster complex (v approximate to 12 000 km s(-1)). These galaxies seem to link two previously identified sheets of galaxies and establish a connection with a third one at v = 15 000 km s(-1) near RA = 13(h). They also tend to fill the gap of galaxies between the foreground Hydra-Centaurus region and the more distant SSC. In the velocity range of the Shapley Supercluster (9000 km s(-1) < cz < 18 000 km s(-1)), we found redshift-space overdensities with b(j) < 17.5 of similar or equal to 5.4 over the 225 square degree central region and similar or equal to 3.8 in a 192 square degree region excluding rich clusters. Over the large region of our survey, we find that the intercluster galaxies make up 48 per cent of the observed galaxies in the SSC region and, accounting for the different completeness, may contribute nearly twice as much mass as the cluster galaxies. In this paper, we discuss the completeness of the velocity catalogue, the morphology of the supercluster, the global overdensity, and some properties of the individual galaxy clusters in the Supercluster.

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This paper presents some initial attempts to mathematically model the dynamics of a continuous estimation of distribution algorithm (EDA) based on a Gaussian distribution and truncation selection. Case studies are conducted on both unimodal and multimodal problems to highlight the effectiveness of the proposed technique and explore some important properties of the EDA. With some general assumptions, we show that, for ID unimodal problems and with the (mu, lambda) scheme: (1). The behaviour of the EDA is dependent only on the general shape of the test function, rather than its specific form; (2). When initialized far from the global optimum, the EDA has a tendency to converge prematurely; (3). Given a certain selection pressure, there is a unique value for the proposed amplification parameter that could help the EDA achieve desirable performance; for ID multimodal problems: (1). The EDA could get stuck with the (mu, lambda) scheme; (2). The EDA will never get stuck with the (mu, lambda) scheme.

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Firmly situating South African teams, players, and associations in the international framework in which they have to compete, South Africa and the Global Game: Football, Apartheid, and Beyond presents an interdisciplinary analysis of how and why South Africa underwent a remarkable transformation from a pariah in world sport to the first African host of a World Cup in 2010. Written by an eminent team of scholars, this special issue and book aims to examine the importance of football in South African society, revealing how the black oppression transformed a colonial game into a force for political, cultural and social liberation. It explores how the hosting of the 2010 World Cup aims to enhance the prestige of the post-apartheid nation, to generate economic growth and stimulate Pan-African pride. Among the themes dealt with are race and racism, class and gender dynamics, social identities, mass media and culture, and globalization. This collection of original and insightful essays will appeal to specialists in African Studies, Cultural Studies, and Sport Studies, as well as to non-specialist readers seeking to inform themselves ahead of the 2010 World Cup. This book was published as a special issue of Soccer and Society. 1. Introduction Peter Alegi and Chris Bolsmann Part 1: Past is Prologue – History of Football in South Africa 2. Football as Code: The Social Diffusion of ‘Soccer’ in South Africa Lloyd Hill 3. White Football in South Africa: Empire, Apartheid and Change, 1892 – 1977 Chris Bolsmann 4. A Biography of Darius Dhlomo: Transnational Footballer in the Era of Apartheid Peter Alegi 5. Women and Gender in South African Soccer Cynthia Fabrizio Pelak Part 2: Football Culture after Apartheid: Local and Transnational Dynamics 6. "You Must Support Chiefs: Pirates Already Have Two White Fans!" Race and Racial Discourse in South African Football Fandom Marc Fletcher 7. "It wasn’t that I did not like South African Football": Media, History, and Biography Sean Jacobs 8. Soccer in a Rugby Town: Restructuring Football in Stellenbosch Sylvain Cubizolles 9. Differing Trajectories: Football Development and Patterns of Player Migration in South Africa and Ghana Paul Darby and Eirik Solberg Part 3: The 2010 World Cup: Challenges and Opportunities 10. Football's Tsars: Proprietorship, Corporatism and Politics in the 2010 FIFA World Cup Scarlett Cornelissen 11. Sports as Cultural Diplomacy: The 2010 FIFA World Cup in South Africa’s Foreign Policy Sifiso Mxolisi Ndlovu 12. World Cup 2010: Africa’s Turn or the Turn on Africa? Ashwin Desai and Goolam Vahed 13. The 2010 FIFA World Cup: Critical Voices From Below Percy Ngonyama.

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This thesis was focused on theoretical models of synchronization to cortical dynamics as measured by magnetoencephalography (MEG). Dynamical systems theory was used in both identifying relevant variables for brain coordination and also in devising methods for their quantification. We presented a method for studying interactions of linear and chaotic neuronal sources using MEG beamforming techniques. We showed that such sources can be accurately reconstructed in terms of their location, temporal dynamics and possible interactions. Synchronization in low-dimensional nonlinear systems was studied to explore specific correlates of functional integration and segregation. In the case of interacting dissimilar systems, relevant coordination phenomena involved generalized and phase synchronization, which were often intermittent. Spatially-extended systems were then studied. For locally-coupled dissimilar systems, as in the case of cortical columns, clustering behaviour occurred. Synchronized clusters emerged at different frequencies and their boundaries were marked through oscillation death. The macroscopic mean field revealed sharp spectral peaks at the frequencies of the clusters and broader spectral drops at their boundaries. These results question existing models of Event Related Synchronization and Desynchronization. We re-examined the concept of the steady-state evoked response following an AM stimulus. We showed that very little variability in the AM following response could be accounted by system noise. We presented a methodology for detecting local and global nonlinear interactions from MEG data in order to account for residual variability. We found crosshemispheric nonlinear interactions of ongoing cortical rhythms concurrent with the stimulus and interactions of these rhythms with the following AM responses. Finally, we hypothesized that holistic spatial stimuli would be accompanied by the emergence of clusters in primary visual cortex resulting in frequency-specific MEG oscillations. Indeed, we found different frequency distributions in induced gamma oscillations for different spatial stimuli, which was suggestive of temporal coding of these spatial stimuli. Further, we addressed the bursting character of these oscillations, which was suggestive of intermittent nonlinear dynamics. However, we did not observe the characteristic-3/2 power-law scaling in the distribution of interburst intervals. Further, this distribution was only seldom significantly different to the one obtained in surrogate data, where nonlinear structure was destroyed. In conclusion, the work presented in this thesis suggests that advances in dynamical systems theory in conjunction with developments in magnetoencephalography may facilitate a mapping between levels of description int he brain. this may potentially represent a major advancement in neuroscience.

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Purpose- This article explores the work practices of Big 4 firms in Bangladesh with the aim of exploring the extent to which Global Professional Service Firms can be thought of as being genuinely ‘global’. Methodology/Approach- Interviews were undertaken with the vast majority of Big 4 partners in Bangladesh. These interviews explored a number of themes related to the professional service work context in Bangladesh and the relationship between local and global firms. Findings- The central finding of this paper is that although the Big 4 have a long-established presence in Bangladesh, local societal factors heavily influence the realities of work for accountants there. In most cases the Big 4 firms establish correspondent firms (instead of full member firms) in Bangladesh and tend to offer restricted service lines. Additionally, the paper identifies professional, commercial and cultural barriers to greater Big 4 involvement in the local market. Conceptually, the chief contribution of this paper is to explore how the effects of globalising capitalism and standardised ‘best practices’ in global professional service work are mediated through the societal effects of Bangladeshi society, resulting in the Big 4 having only a tentative presence in the Bangladeshi market. Research implications- The findings cast doubt on the extent to which self-styled Global Professional Service firms are truly ‘global’ in nature. Future work examining the Big 4, or accounting more generally, in the context of globalization, would do well to pay greater attention to the experience of professionals in emerging markets. Originality/Value- Whilst there has been much work looking at accounting and accountants in the context of globalization, this work has tended to privilege ‘core’ western empirical settings. Very little is known about Professional Service Firms in ‘peripheral’ or emerging markets. Furthermore, this study extends the application of the System, Society and Dominance framework by mapping the interactions and dynamics of these three sources of influence in the setting of PSFs.

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The paper applies the GVC framework to analyse the organisational and geographical reconfiguration of the global R&D function of leading US and European pharmaceutical MNCs. Though pharmaceutical MNCs have been outsourcing clinical trial activities since the mid-1990s, the outsourcing of discovery research tasks is a phenomenon of the 2000s (Ramirez 2013). Moreover, in the context of a crisis of R&D productivity and increasing pressure from shareholders, a number of US and European pharmaceutical MNCs are breaking up their R&D function in an attempt to increase flexibility and reduce risk as well as costs and are thereby restructuring the global architecture of their R&D function. This break-up, or unbundling (Sako 2006), of the R&D function is particularly interesting given the prevalence of market failure in innovation (Howells et al 2008), the non-modular nature of the R&D process in this industry (Pisano 2006) and the strategic important of this activity to the core competence and long-term competitive advantage of firms in this sector. The focus of this paper is on the outsourcing of R&D activities to Chinese and Indian independently-owned contract research organisations (CROs) and the way these firms are becoming integrated as service providers into the global R&D function (or R&D value chain) of pharmaceutical MNCs. Above all the paper is concerned with the development of capabilities of CROs from these two countries and the dynamics of upgrading in GVCs in knowledge-intensive functions. The paper therefore discusses the role of both knowledge flows within global pharmaceutical R&D value chains as well as national innovation systems on the development of capabilities of Chinese and Indian CROs. Our analysis is based on data from semi-structured interviews collected from senior R&D managers from a sample of ten US and European pharmaceutical MNCs and owners and senior R&D managers from five Chinese and five Indian CROs who are providing research services to MNCs in this industry. We discuss the emergence of R&D outsourcing in this industry and the nature and mechanisms of knowledge flows within R&D value chains. The embeddedness of CROS in the national innovation systems of their home countries is also discussed.

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The goal of mangrove restoration projects should be to improve community structure and ecosystem function of degraded coastal landscapes. This requires the ability to forecast how mangrove structure and function will respond to prescribed changes in site conditions including hydrology, topography, and geophysical energies. There are global, regional, and local factors that can explain gradients of regulators (e.g., salinity, sulfides), resources (nutrients, light, water), and hydroperiod (frequency, duration of flooding) that collectively account for stressors that result in diverse patterns of mangrove properties across a variety of environmental settings. Simulation models of hydrology, nutrient biogeochemistry, and vegetation dynamics have been developed to forecast patterns in mangroves in the Florida Coastal Everglades. These models provide insight to mangrove response to specific restoration alternatives, testing causal mechanisms of system degradation. We propose that these models can also assist in selecting performance measures for monitoring programs that evaluate project effectiveness. This selection process in turn improves model development and calibration for forecasting mangrove response to restoration alternatives. Hydrologic performance measures include soil regulators, particularly soil salinity, surface topography of mangrove landscape, and hydroperiod, including both the frequency and duration of flooding. Estuarine performance measures should include salinity of the bay, tidal amplitude, and conditions of fresh water discharge (included in the salinity value). The most important performance measures from the mangrove biogeochemistry model should include soil resources (bulk density, total nitrogen, and phosphorus) and soil accretion. Mangrove ecology performance measures should include forest dimension analysis (transects and/or plots), sapling recruitment, leaf area index, and faunal relationships. Estuarine ecology performance measures should include the habitat function of mangroves, which can be evaluated with growth rate of key species, habitat suitability analysis, isotope abundance of indicator species, and bird census. The list of performance measures can be modified according to the model output that is used to define the scientific goals during the restoration planning process that reflect specific goals of the project.