957 resultados para Natural law.


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Darwin observed that multiple, lowly organized, rudimentary, or exaggerated structures show increased relative variability. However, the cellular basis for these laws has never been investigated. Some animals, such as the nematode Caenorhabditis elegans, are famous for having organs that possess the same number of cells in all individuals, a property known as eutely. But for most multicellular creatures, the extent of cell number variability is unknown. Here we estimate variability in organ cell number for a variety of animals, plants, slime moulds, and volvocine algae. We find that the mean and variance in cell number obey a power law with an exponent of 2, comparable to Taylor's law in ecological processes. Relative cell number variability, as measured by the coefficient of variation, differs widely across taxa and tissues, but is generally independent of mean cell number among homologous tissues of closely related species. We show that the power law for cell number variability can be explained by stochastic branching process models based on the properties of cell lineages. We also identify taxa in which the precision of developmental control appears to have evolved. We propose that the scale independence of relative cell number variability is maintained by natural selection.

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An analysis of the initial antigen-recognition step in the destruction of target cells by CD8+ cytolytic T lymphocytes (CTLs) shows that a relationship in the form of the law of mass action can be used to describe interactions between antigen-specific receptors on T cells (TCRs) and their natural ligands on target cells (peptide-major histocompatibility protein complexes, termed pepMHC complexes), even though these reactants are confined to their respective cell membranes. For a designated level of lysis and receptor affinities below about 5 X 10(6) M-1, the product of the required number of pepMHC complexes per target cell ("epitope density") and TCR affinity for pepMHC complexes is constant; therefore, over this range TCR affinities can be predicted from epitope densities (or vice versa). At higher receptor affinities ("affinity ceiling") the epitope density required for half-maximal lysis reaches a lower limit of less than 10 complexes per target cell.

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This collection of short essays arose from the inaugural meeting of the Idaho Symposium on Energy in the West, which was held in November, 2014. The topic for this first Symposium was Transmission and Transport of Energy in the Western U.S. and Canada: A Law and Policy Road Map. The essays in this collection provide a notable introduction to the major energy issues facing the West today. Topics include: building a resilient legal architecture for western energy production; natural gas flaring; transmission planning for wind energy; utilities and rooftop solar; special considerations for western states and the Clean Power Plan; the Clean Power Plan's implications for the western grid; siting renewable energy on public lands; and implications of utility reform in New York and Hawaii for the Northwest.

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Notebook with a handwritten copy of lecture summaries for a physics course given by Harvard Professor John Winthrop. The notes were made by Timothy Foster in 1772 and 1773. The volume contains twenty-five lectures with some diagrams.

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This letter was written aboard the U.S.S. Franklin. Stewart writes in detail about William’s brother Henry James (Harry) Tudor, and concerns about his character, particularly his "natural indolence and indifference." He notes that like his wife, Delia, Harry spends money irresponsibly. Stewart also writes he tried to interest Harry in the pursership of the Franklin, and had hoped he would be appointed to the Consulate of Tripoli or Tunis.

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This layer is a georeferenced raster image of the historic paper map entitled: Map of London and its environs : shewing the boundary of the jurisdiction of the metropolitan board of work, also the boundaries of the city of London, and of the Poor Law unions. It was published by Edward Standford, April 21, 1884. Scale [ca. 1:31,680]. This map is part of a 5 map set showing various thematic districts and boundaries of the London region. The image inside the map neatline is georeferenced to the surface of the earth and fit to the British National Grid coordinate system (British National Grid, Airy Spheroid OSGB (1936) Datum). All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as roads, railroads, drainage, selected private and public buildings, towns and villages, cemeteries, parks, farms, Poor Law unions, and more. Relief is shown by hachures. This layer is part of a selection of digitally scanned and georeferenced historic maps from The Harvard Map Collection as part of the Imaging the Urban Environment project. Maps selected for this project represent major urban areas and cities of the world, at various time periods. These maps typically portray both natural and manmade features at a large scale. The selection represents a range of regions, originators, ground condition dates, scales, and purposes.

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Introduction. The essential facilities doctrine may be seen as the ‘extra weight’ which is put onto the balance, in order to give precedence to the maintenance of competition over the complete contractual freedom of undertakings controlling an important and unique facility. The main purpose of the doctrine is to impose upon such ‘dominant’ undertakings the duty to negotiate and/or give access to the facility, against a reasonable fee, to other undertakings, which cannot pursue their own activity (and therefore will perish) without access to such a facility. This very simple description of the content of the doctrine underlines its limitations: through the imposition of a duty to negotiate or contractual obligations, the rule tends to compensate for the weaknesses of the competitive structure of a market, which are due to the existence of some essential facility. In other words, the doctrine does not by itself provide a definitive solution to the lack of competition, but tends to contractually maintain or even create some competition.1 The doctrine of essential facilities originates in the US antitrust case law of the Circuit and District Courts, but has never been officially acknowledged by the Supreme Court. It has been further developed and hotly debated by scholars in the US, both from a legal and from an economic viewpoint. In the EU, the essential facilities doctrine was openly introduced by the Commission during the early 1990s, but has received only limited and indirect support by the Court of First Instance (the CFI) and the European Court of Justice (the ECJ). It also indirectly inspired the legislation concerning the deregulation of traditional ‘natural’ monopolies. The judicial origin of the doctrine, combined with the hesitant application by the appeal courts, both in the US and the EU, cast uncertainty not only on the precise scope of the doctrine, but also on the issue of its very existence. These questions receive a particular light within the EU context, where the doctrine is called upon to play a different role from its US counterpart. In order to address the above issues, we will first pretend that an EU essential facility doctrine does indeed exist and we shall try to identify the scope and content thereof, through its main applications (Section 1). Subsequently, we will try to answer the question whether such a doctrine should exist at all in the EU (Section 2).

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In light of the growing international competition among states and globally operating companies for limited natural resources, export restrictions on raw materials have become a popular means for governments to strive for various goals, including industrial development, natural resource conservation and environmental protection. For instance, China as a major supplier of many raw materials has been using its powerful position to both economic and political ends. The European Union (EU), alongside economic heavyweights such as the US, Japan and Mexico, launched two high-profile cases against such export restrictions by China at the WTO in 2009 and 2012. Against this background, this paper analyses the EU’s motivations in the initiation of trade disputes on export restrictions at WTO, particularly focusing on the two cases with China. It argues that the EU's WTO complaints against export restrictions on raw materials are to a large extent motivated by its economic and systemic interests rather than political interests. The EU is more likely to launch a WTO complaint, the stronger the potential and actual impact on its economy, the more ambiguous the WTO rules and the stronger the internal or external lobbying by member states or companies. This argumentation is based on the analysis of pertinent factors such as the economic impact, the ambiguity of WTO law on export restrictions and the pressure by individual member states on the EU as well as the role of joint complaints at the WTO and political considerations influencing the EU’s decision-making process.

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"Prefatory memoir" signed: G.B.M. [i.e. G. B. Morgan]

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"B-242275"--P. [1]