8,584 research outputs found

    Chief Kerry's moose : a guidebook to land use and occupancy mapping, research design, and data collection

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    Aboriginal peoples in Canada have been mapping aspects of their cultures for more than a generation. Indians, Inuit, MĂ©tis, non-status Indians and others have called their maps by different names at various times and places: land use and occupancy; land occupancy and use; traditional use; traditional land use and occupancy; current use; cultural sensitive areas; and so on. I use “land use and occupancy mapping” in a generic sense to include all the above. The term refers to the collection of interview data about traditional use of resources and occupancy of lands by First Nation persons, and the presentation of those data in map form. Think of it as the geography of oral tradition, or as the mapping of cultural and resource geography. (PDF contains 81 pages.

    Investigation of two photon emission in strong field QED using channeling in a crystal

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    We investigate the 2nd order process of two photons being emitted by a high-energy electron dressed in the strong background electric field found between the planes in a crystal. The strong crystalline field combined with ultra relativistic electrons is one of very few cases where the Schwinger field can be experimentally achieved in the electron's rest frame. The radiation being emitted, the so-called channeling radiation, is a well studied phenomenon. However only the first order diagram corresponding to emission of a single photon has been studied so far. We elaborate on how the 2 photon emission process should be understood in terms of a two-step versus a one-step process, i.e., if one can consider one photon being emitted after the other, or if there is also a contribution where the two photons are emitted 'simultaneously'. From the calculated full probability we see that the two-step contribution is simply the product of probabilities for single photon emission while the additional one-step terms are, mainly, interferences due to several possible intermediate virtual states. These terms can contribute significantly when the crystal is thin. Therefore, in addition, we see how one can, for a thick crystal, calculate multiple photon emissions quickly by neglecting the one-step terms, which represents a solution of the problem of quantum radiation reaction in a crystal beyond the usually applied constant field approximation. We explicitly calculate an example of 180 GeV electrons in a thin Silicon crystal and argue why it is, for experimental reasons, more feasible to see the one-step contribution in a crystal experiment than in a laser experiment

    GLAND CELLS IN HYDRA

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    The proliferative capacity of gland cells in Hydra attenuata was investigated. The results indicate that both gland cell proliferation and interstitial cell differentiation to gland cells contribute to the maintenance of the whole population. On the basis of [3H]thymidine incorporation and nuclear DNA measurements, gland cells consist of at least three different populations. One population consists of rapidly proliferating cells with a cell cycle of about 72 h. These cells are distributed throughout the body column. In the lower gastric region there is a population of non-cycling cells in G2 while in the upper gastric region there is a population of noncycling cells in G1. About half the G1 population becomes a new antigen, SEC 1, which is typical of mucus cells

    Complete treatment of single-photon emission in planar channeling

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    Approximate solutions of the Dirac equation are found for ultrarelativistic particles moving in a periodic potential, which depends only on one coordinate, transverse to the largest component of the momentum of the incoming particle. As an example we employ these solutions to calculate the radiation emission of positrons and electrons trapped in the planar potential found between the (110) planes in Silicon. This allows us to compare with the semi-classical method of Baier, Katkov and Strakhovenko, which includes the effect of spin and photon recoil, but neglects the quantization of the transverse motion. For high-energy electrons, the high-energy part of the angularly integrated photon energy spectrum calculated with the found wave functions differs from the corresponding one calculated with the semi-classical method. However, for lower particle energies it is found that the angularly integrated emission energy spectra obtained via the semi-classical method is in fairly good agreement with the full quantum calculation except that the positions of the harmonic peaks in photon energy and the photon emission angles are shifted

    National economic impacts of an EU environmental policy: an applied general equilibrium analysis

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    The objective of this paper is to quantify the economic effects of the introduction of a system of tradable permits in the European Union (EU). For this purpose we use linked applied general equilibrium models (AGE) for eleven EU member countries. This method enables us to measure the change in competitiveness for domestic industries, the impact on growth, employment and inflation in member countries, and the cost and benefits of a cooperative approach to adhere to a EU target of emissions of air pollutants. The results we will present are first results from the SOLVGE/GEM-E3 Projekt. GEM-E3 stands for General Equilibrium Modeling for Energy - Economy - Environment, a joint undertaking of NTUA-Athens (P. Capros, P. Georgakopoulos), CESKULeuven (S. Proost and D. Van Regemorter), Univ. Mannheim and ZEW (K. Conrad and T. Schmidt), GEMME-CEA (N. Ladoux), Univ. Strathclyde (P. MacGregor), CORE-UCL (Y. Smeers), With respect to a policy on greenhouse gases we will quantify the economic impact for the, EU by introducing a EU-wide tradable permit system, free of charge and based on the present energy intensity and energy mix. Under growth there will be a positive market price for permits with demand by countries where the cost of substitution are high and supply by those countries where the cost of substitution are low. We will measure economic performance and trade flows under a noncoordinated CO2 policy where each country limits the emission of CO2 by 10% and will compare the result with a cooperative outcome where the European Union as a decision maker aims at reducing CO2 by 10%. --

    Climate change policy and burden sharing in the European Union: applying alternative equity rules to a CGE-framework

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    The objective of this paper is to present different equity rules that can be applied to the initial allocation of greenhouse gas entitlements and to analyse the potential impacts of these rules EU-wide as well as on the level of member states. The methodological framework used in the empirical part of the paper is based on the GEM-E3 model, a multi-country and multi-sectoral computable general equilibrium model for fourteen EU-member states. The major finding of the paper is that being ex ante favoured with respect to the initial allocation of permits might not hold ex post, i.e. when trade of permits and actual emission reductions are carried out. The reason can be found in two effects. First, the interdependence of the EU economies allows smaller economies not to make full use of the advantages they get through the ability-to-pay allocation: The negative impact on the economic perfomance of the big economies leads to a drop of export demand in the smaller economies, which in turn lowers the expected positive impact on welfare in the latter ones. Second, the way of how a surplus of permits in a particular country is used has considerable impacts on consumer welfare. Selling the surplus of permits on the international market and use the receipts to reduce public deficit is one way, but it has no direct impact on demand. Other, more demand stimulating recycling strategies of the surplus (e.g. a lump-sum transfer to households) might be more promising if welfare losses are to be minimzed. Both effects may outweigh the positive effect realized ex ante in some countries due to a more ?fair? initial allocation of permits. The outcome emphasizes the importance of a consideration of full general equilibrium effects across countries. --

    Modelling of foreign trade in applied general equilibrium models: theoretical approaches and sensitivity analysis with the GEM-E3 model

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    The specification of the world closure, i.e. the way of closing the domestic economy model by incorporating the external sector, is a crucial component for those models in which production and consumption is not specified endogenously for all countries. This paper looks explicitly at the assumptions concerning the trade behaviour of the rest of the world that can be found in literature and in empirical applications, such as the GEM-E3 General Equilibrium Model for the EU. Starting from a description of the closure rule in the actual GEM-E3 model version, two main changes in the foreign trade specification are proposed and tested using an EU-wide ecological tax reform scenario. The first change refers to the rest of the world?s export supply function in which a constant finite price elasticity is introduced. The second change concerns the rest of the world?s import demand function in which an activity variable is incorporated. In summary, the impact in terms of economic welfare and changes in macroeconomic variables is noteworthy for the former case while no substantial changes could be observed for the latter case. Additionally, the sensitivity of the GEM-E3 model to variations in key parameter values such as the upper-level Armington elasticity are analysed. Results indicate that the model can be interpreted as quite robust to parameter changes. --

    Double dividend of climate protection and the role of international policy coordination in the EU: an applied general equilibrium analysis with the GEM-E3 model

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    While there is some hope that the ongoing climate change negotiations will soon come up with concrete, time scheduled and binding emission reduction commitments, the question of how to achieve these targets is still unsolved. The objective of this paper is to analyse alternative settings of an environmental tax reform and its economic and environmental impacts on the EU. The methodological framework used is based on a multi-country and multi-sectoral computable general equilibrium model for eleven EU-member states. The emphasis of the analysis lies on the institutional setting of a carbon dioxide reduction policy and on the specification of the labour market. The institutional settings analysed are related to the degree of environmental policy coordination. As standard neo-classics neglegt the problem of unvoluntary unemployment, we relax this restriction in the second part of the analysis in order to test alternative (more rigid) labour market specifications. The major findings of the paper can be summarized as follows: 1) There is some potential for a double dividend in the EU. 2) Coordination beats not always unilateral actions. 3) Labour market rigidities play a crucial role to both, the double dividend and the coordination issue. --
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