994 resultados para Govern
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By using the method of operators of multiple scales, two coupled nonlinear equations are derived, which govern the slow amplitude modulation of surface gravity waves in two space dimensions. The equations of Davey and Stewartson, which also govern the two-dimensional modulation of the amplitude of gravity waves, are derived as a special case of our equations. For a fully dispersed wave, symmetric about a point which moves with the group velocity, the coupled equations reduce to a nonlinear Schrödinger equation with extra terms representing the effect of the curvature of the wavefront.
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This chapter provides a critical legal geography of outer Space, charting the topography of the debates and struggles around its definition, management, and possession. As the emerging field of critical legal geography demonstrates, law is not a neutral organiser of space, but is instead a powerful cultural technology of spatial production. Drawing on legal documents such as the Outer Space Treaty and the Moon Treaty, as well as on the analogous and precedent-setting legal geographies of Antarctica and the deep seabed, the chapter addresses key questions about the legal geography of outer Space, questions which are of growing importance as Space’s available satellite spaces in the geostationary orbit diminish, Space weapons and mining become increasingly viable, Space colonisation and tourism emerge, and questions about Space’s legal status grow in intensity. Who owns outer Space? Who, and whose rules, govern what may or may not (literally) take place there? Is the geostationary orbit the sovereign property of the equatorial states it supertends, as these states argued in the 1970s? Or is it a part of the res communis, or common property of humanity, which currently legally characterises outer Space? Does Space belong to no one, or to everyone? As challenges to the existing legal spatiality of outer Space emerge from spacefaring states, companies, and non-spacefaring states, it is particularly critical that the current spatiality of Space is understood and considered.
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DNA topoisomerases are ubiquitous nuclear enzymes that govern the topological interconversions of DNA by transiently breaking/rejoining the phosphodiester backbone of one (type I) or both (type II) strands of the double helix. Consistent with these functions, topoisomerases play key roles in many aspects of DNA metabolism. Type II DNA topoisomerase (topo II) is vital for various nuclear processes, including DNA replication, chromosome segregation, and maintenance of chromosome structure. Topo II expression is regulated at multiple stages, including transcriptional, posttranscriptional, and posttranslational levels, by a multitude of signaling factors. Topo II is also the cellular target for a variety of clinically relevant anti-tumor drugs. Despite significant progress in our understanding of the role of topo II in diverse nuclear processes, several important aspects of topo II function, expression, and regulation are poorly understood. We have focused this review specifically on eukaryotic DNA topoisomerase II, with an emphasis on functional and regulatory characteristics.
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The continuous production of blood cells, a process termed hematopoiesis, is sustained throughout the lifetime of an individual by a relatively small population of cells known as hematopoietic stem cells (HSCs). HSCs are unique cells characterized by their ability to self-renew and give rise to all types of mature blood cells. Given their high proliferative potential, HSCs need to be tightly regulated on the cellular and molecular levels or could otherwise turn malignant. On the other hand, the tight regulatory control of HSC function also translates into difficulties in culturing and expanding HSCs in vitro. In fact, it is currently not possible to maintain or expand HSCs ex vivo without rapid loss of self-renewal. Increased knowledge of the unique features of important HSC niches and of key transcriptional regulatory programs that govern HSC behavior is thus needed. Additional insight in the mechanisms of stem cell formation could enable us to recapitulate the processes of HSC formation and self-renewal/expansion ex vivo with the ultimate goal of creating an unlimited supply of HSCs from e.g. human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPS) to be used in therapy. We thus asked: How are hematopoietic stem cells formed and in what cellular niches does this happen (Papers I, II)? What are the molecular mechanisms that govern hematopoietic stem cell development and differentiation (Papers III, IV)? Importantly, we could show that placenta is a major fetal hematopoietic niche that harbors a large number of HSCs during midgestation (Paper I)(Gekas et al., 2005). In order to address whether the HSCs found in placenta were formed there we utilized the Runx1-LacZ knock-in and Ncx1 knockout mouse models (Paper II). Importantly, we could show that HSCs emerge de novo in the placental vasculature in the absence of circulation (Rhodes et al., 2008). Furthermore, we could identify defined microenvironmental niches within the placenta with distinct roles in hematopoiesis: the large vessels of the chorioallantoic mesenchyme serve as sites of HSC generation whereas the placental labyrinth is a niche supporting HSC expansion (Rhodes et al., 2008). Overall, these studies illustrate the importance of distinct milieus in the emergence and subsequent maturation of HSCs. To ensure proper function of HSCs several regulatory mechanisms are in place. The microenvironment in which HSCs reside provides soluble factors and cell-cell interactions. In the cell-nucleus, these cell-extrinsic cues are interpreted in the context of cell-intrinsic developmental programs which are governed by transcription factors. An essential transcription factor for initiation of hematopoiesis is Scl/Tal1 (stem cell leukemia gene/T-cell acute leukemia gene 1). Loss of Scl results in early embryonic death and total lack of all blood cells, yet deactivation of Scl in the adult does not affect HSC function (Mikkola et al., 2003b. In order to define the temporal window of Scl requirement during fetal hematopoietic development, we deactivated Scl in all hematopoietic lineages shortly after hematopoietic specification in the embryo . Interestingly, maturation, expansion and function of fetal HSCs was unaffected, and, as in the adult, red blood cell and platelet differentiation was impaired (Paper III)(Schlaeger et al., 2005). These findings highlight that, once specified, the hematopoietic fate is stable even in the absence of Scl and is maintained through mechanisms that are distinct from those required for the initial fate choice. As the critical downstream targets of Scl remain unknown, we sought to identify and characterize target genes of Scl (Paper IV). We could identify transcription factor Mef2C (myocyte enhancer factor 2 C) as a novel direct target gene of Scl specifically in the megakaryocyte lineage which largely explains the megakaryocyte defect observed in Scl deficient mice. In addition, we observed an Scl-independent requirement of Mef2C in the B-cell compartment, as loss of Mef2C leads to accelerated B-cell aging (Gekas et al. Submitted). Taken together, these studies identify key extracellular microenvironments and intracellular transcriptional regulators that dictate different stages of HSC development, from emergence to lineage choice to aging.
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This exploratory article examines the phenomenon of the ‘Quantified Self’—until recently, a subculture of enthusiasts who aim to discover knowledge about themselves and their bodies through self-tracking, usually using wearable devices to do so—and its implications for laws concerned with regulating and protecting health information. Quantified Self techniques and the ‘wearable devices’ and software that facilitate them—in which large transnational technology corporations are now involved—often involve the gathering of what would be considered ‘health information’ according to legal definitions, yet may occur outside the provision of traditional health services (including ‘e-health’) and the regulatory frameworks that govern them. This article explores the legal and regulatory framework for self-quantified health information and wearable devices in Australia and determines the extent to which this framework addresses privacy and other concerns that these techniques engender, along with suggestions for reform.
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Aeration experiments were conducted in different sized baffled and unbaffled circular surface aeration tanks to study their relative performance on oxygen transfer process while aerating the same volume of water. Experiments were carried out with the objective of ascertaining the effect of baffle on oxygen transfer coefficient k. Simulation equations govern the oxygen transfer coefficient with the theoretical power per unit volume, X and actual power per unit volume, P-V. It has been found that, for any given X, circular tanks with baffle produce higher values of k than unbaffled circular tanks, but in terms of actual power consumption unbaffled tanks consume less power when compared to baffled circular tanks to achieve the same value of k. It has been found that in terms of energy consumption, epsilon, baffled tanks consume more energy than unbaffled tanks at any value of X. This suggests that the unbaffled circular tank gives a better performance as far as energy consumption is concerned and hence better economy. An example illustrating the energy conservation to aerate the same volume of water in both types of aerators is given. (c) 2007 Society of Chemical Industry.
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Advertising and marketing institutions produce categorisations of different groups of population. These categorisations serve as tools for addressing the potential consumers. This research is about how and what kind of categorisations of consumerhood are produced and how they are used as governing patterns within the institutions of advertising. My goal is to shed light on methods, cultural patterns and discourses for making people become consumers, objects for marketing measures. The data consists of 23 qualitative thematic interviews with Finnish advertising professionals. Moreover, examples are drawn from professional magazines and brochures of media agencies and marketing research organisations. First, I present some of the the official consumer categories in the consumer monitors produced by research organisations. Then, I analyse the unofficial consumer categories which are produced by advertising professionals in the interviews. The methodological framework is based on discourse theory and especially on Michel Foucault s ideas on power, governmentality, and discourses. Discursive categorisation of the population is one of the means of governmentality used in marketing and advertising. Knowledge of the consumer research is used as a tool for governing the potential consumers. Even though the real consumers always have a possibility to behave against the marketer s wishes. The marketers can not make people buy certain products or services, but they aim at influencing people in a way that they want to buy the products and start to govern themselves. As result, I present six unofficial discursive consumer categories, which are used by the advertising professionals. The consumerhood may be represented as rational, self-fulfilling, indifferent, whimsical, manipulated or sovereign. However, The discursive consumer categorisations are overlapping and controversial. The interviewed advertising professionals construct their own particular position in relation to the consumers which are viewed as others . On the other, the interviewees may talk about themselves as consumers. Finally, I maintain that the consumers and target groups of advertising are viewed as commodities in advertising institutions. The end product of the product development is not only the product but the aim is to produce the consumer of the product. The research of the ways advertising professionals aim to govern the consumers gives knowledge on the networks of power in which people act within consumer culture.
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The starting point of this study was to find out how the historical consciousness manifest in conceptions and experiences of Chilean refugees and their descendants. The previous research of historical consciousness has shown that powerful experiences such as the revolution and being a refugee may have an effect on historical consciousness. The purpose of this study is to solve how those experiences in the past have influenced Chilean refugees and their descendant s interpretations of the present and expectations for the future. The research material was collected by interviewing four Chilean refugees that escaped to Finland in years 1973 1976 and four young adults who represent the second generation. All second generation interviewees were born in Finland and their other parent or both parents were Chilean refugees. The two groups were not in a family relation to each other. The empirical part of the research was made by qualitative methods. The research material was collected by the method of focused interview and it was analysed by the qualitative data analysis software Atlas.ti 6.0. Content analysis was the main research tool. The previous theory of historical consciousness and the study questions was used to create the seven categories that manifest historical consciousness. The seven categories were biographical memory, collective memory, experiences of living between two cultures, idea of man, the essence of history and the reason for living, value conceptions and expectations of the future. Content analysis was based on those categories. Subcategories were based on the research material and were created during the analysis. The results of this study were made up of categories. The study revealed that experiences of revolution and of being a refugee has a significant role in the historical consciousness of the Chilean refugees. It became evident in their biographical memory being separated in three parts, in their values and in the belief of possibility of an individual to govern her own life. The second generation was also exposed to their parent s experiences in the past. The collective trauma in their parent s past has been part of their life indirectly and has affected the way they think of themselves, their concepts and their place in the present world. The active and regular retrospection in Finland by Chilean adults and special Gabriela Mistral club activities has played a big part in the construction of their historical consciousness.
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The four scientific articles comprising this doctoral dissertation offer new information on the presentation and construction of addiction in the mass media during the period 1968 - 2008. Diachronic surveys as well as quantitative and qualitative content analyses were undertaken to discern trends during the period in question and to investigate underlying conceptions of the problems in contemporary media presentations. The research material for the first three articles consists of a sample of 200 texts from Finland s biggest daily newspaper, Helsingin Sanomat, from the period 1968 - 2006. The fourth study examines English-language tabloid material published on the Internet in 2005 - 2008. A number of principal trends are identified. In addition to a significant increase in addiction reporting over time, the study shows that an internalisation of addiction problems took place in the media presentations under study. The phenomenon is portrayed and tackled from within the problems themselves, often from the viewpoint of the individuals concerned. The tone becomes more personal, and technical and detailed accounts are more and more frequent. Secondly, the concept of addiction is broadened. This can be dated to the 1990s. The concept undergoes a conventionalisation: it is used more frequently in a manner that is not thought to require explanation. The word riippuvuus (the closest equivalent to addiction in Finnish) was adopted more commonly in the reporting at the same time, in the 1990s. Thirdly, the results highlight individual self-governance as a superordinate principle in contemporary descriptions of addiction. If the principal demarcation in earlier texts was between us and them , it is now focused primarily on the individual s competence and ability to govern the self, to restrain and master one's behaviour. Finally, in the fourth study investigating textual constructions of female celebrities (Amy Winehouse, Britney Spears and Kate Moss) in Internet tabloids, various relations and functions of addiction problems, intoxication, body and gender were observed to function as cultural symbols. Addiction becomes a sign, or a style, that represents different significations in relation to the main characters in the tabloid stories. Tabloids, as a genre, play an important role by introducing other images of the problems than those featured in mainstream media. The study is positioned within the framework of modernity theory and its views on the need for self-reflexivity and biographies as tools for the creation and definition of the self. Traditional institutions such as the church, occupation, family etc. no longer play an important role in self-definition. This circumstance creates a need for a culture conveying stories of success and failure in relation to which the individual can position their own behaviour and life content. I propose that addiction , as a theme in media reporting, resolves the conflict that emanates from the ambivalence between the accessibility and the individualisation of consumer society, on the one hand, and the problematic behavioural patterns (addictions) that they may induce, on the other.
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"The Protection of Traditional Knowledge Associated with Genetic Resources: The Role of Databases and Registers" ABSTRACT Yovana Reyes Tagle The misappropriation of TK has sparked a search for national and international laws to govern the use of indigenous peoples knowledge and protection against its commercial exploitation. There is a widespread perception that biopiracy or illegal access to genetic resources and associated traditional knowledge (TK) continues despite national and regional efforts to address this concern. The purpose of this research is to address the question of how documentation of TK through databases and registers could protect TK, in light of indigenous peoples increasing demands to control their knowledge and benefit from its use. Throughout the international debate over the protection of TK, various options have been brought up and discussed. At its core, the discussion over the legal protection of TK comes down to these issues: 1) The doctrinal question: What is protection of TK? 2) The methodological question: How can protection of TK be achieved? 3) The legal question: What should be protected? And 4) The policy questions: Who has rights and how should they be implemented? What kind of rights should indigenous peoples have over their TK? What are the central concerns the TK databases want to solve? The acceptance of TK databases and registers may bring with it both opportunities and dangers. How can the rights of indigenous peoples over their documented knowledge be assured? Documentation of TK was envisaged as a means to protect TK, but there are concerns about how documented TK can be protected from misappropriation. The methodology used in this research seeks to contribute to the understanding of the protection of TK. The steps taken in this research attempt to describe and to explain a) what has been done to protect TK through databases and registers, b) how this protection is taking place, and c) why the establishment of TK databases can or cannot be useful for the protection of TK. The selected case studies (Peru and Venezuela) seek to illustrate the complexity and multidisciplinary nature of the establishment of TK databases, which entail not only legal but also political, socio-economic and cultural issues. The study offers some conclusions and recommendations that have emerged after reviewing the national experiences, international instruments, work of international organizations, and indigenous peoples perspectives. This thesis concludes that if TK is to be protected from disclosure and unauthorized use, confidential databases are required. Finally, the TK database strategy needs to be strengthened by the legal protection of the TK itself.
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Energy harvesting sensors (EHS), which harvest energy from the environment in order to sense and then communicate their measurements over a wireless link, provide the tantalizing possibility of perpetual lifetime operation of a sensor network. The wireless communication link design problem needs to be revisited for these sensors as the energy harvested can be random and small and not available when required. In this paper, we develop a simple model that captures the interactions between important parameters that govern the communication link performance of a EHS node, and analyze its outage probability for both slow fading and fast fading wireless channels. Our analysis brings out the critical importance of the energy profile and the energy storage capability on the EHS link performance. Our results show that properly tuning the transmission parameters of the EHS node and having even a small amount of energy storage capability improves the EHS link performance considerably.
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This paper presents the results of a computational study of laminar axisymmetric plumes generated by the simultaneous diffusion of thermal energy and chemical species. Species concentrations are assumed small. The plume is treated as a boundary layer. Boussinesq approximations are incorporated and the governing conservation equations of mass, momentum, energy and species are suitably non-dimensionalised. These equations are solved using one time-step-forward explicit finite-difference method. Upwind differencing is employed for convective terms. The results thus obtained are explained in terms of the basic physical mechanisms that govern these flows. They show many interesting aspects of the complex interaction of the two buoyant mechanisms.
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System of kinematical conservation laws (KCL) govern evolution of a curve in a plane or a surface in space, even if the curve or the surface has singularities on it. In our recent publication K. R. Arun, P. Prasad, 3-D kinematical conservation laws (KCL): evolution of a surface in R-3-in particular propagation of a nonlinear wavefront, Wave Motion 46 (2009) 293-311] we have developed a mathematical theory to study the successive positions and geometry of a 3-D weakly nonlinear wavefront by adding an energy transport equation to KCL. The 7 x 7 system of equations of this KCL based 3-D weakly nonlinear ray theory (WNLRT) is quite complex and explicit expressions for its two nonzero eigenvalues could not be obtained before. In this short note, we use two different methods: (i) the equivalence of KCL and ray equations and (ii) the transformation of surface coordinates, to derive the same exact expressions for these eigenvalues. The explicit expressions for nonzero eigenvalues are important also for checking stability of any numerical scheme to solve 3-D WNLRT. (C) 2010 Elsevier Inc. All rights reserved.
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The peaking of most oil reserves and impending climate change are critically driving the adoption of solar photovoltaic's (PV) as a sustainable renewable and eco-friendly alternative. Ongoing material research has yet to find a breakthrough in significantly raising the conversion efficiency of commercial PV modules. The installation of PV systems for optimum yield is primarily dictated by its geographic location (latitude and available solar insolation) and installation design (tilt, orientation and altitude) to maximize solar exposure. However, once these parameters have been addressed appropriately, there are other depending factors that arise in determining the system performance (efficiency and output). Dust is the lesser acknowledged factor that significantly influences the performance of the PV installations. This paper provides an appraisal on the current status of research in studying the impact of dust on PV system performance and identifies challenges to further pertinent research. A framework to understand the various factors that govern the settling/assimilation of dust and likely mitigation measures have been discussed in this paper. (C) 2010 Elsevier Ltd. All rights reserved.
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The evolution of crystallographic texture in polycrystalline copper and nickel has been studied. The deformation texture evolution in these two materials over seven orders of magnitude of strain rate from 3 x 10(-4) to similar to 2.0 x 10(+3) s(-1) show little dependence on the stacking fault energy (SFE) and the amount of deformation. Higher strain rate deformation in nickel leads to weakerh < 101 > texture because of extensive microband formation and grain fragmentation. This behavior, in turn, causes less plastic spin and hence retards texture evolution. Copper maintains the stable end < 101 > component over large strain rates (from 3 x 10(-4) to 10(+2) s(-1)) because of its higher strain-hardening rate that resists formation of deformation heterogeneities. At higher strain rates of the order of 2 x 10(+3) s(-1), the adiabatic temperature rise assists in continuous dynamic recrystallization that leads to an increase in the volume fraction of the < 101 > component. Thus, strain-hardening behavior plays a significant role in the texture evolution of face-centered cubic materials. In addition, factors governing the onset of restoration mechanisms like purity and melting point govern texture evolution at high strain rates. SFE may play a secondary role by governing the propensity of cross slip that in turn helps in the activation of restoration processes.