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Thomas Wieland's book is the first survey on the history of scientific plant breeding in Germany from 1889 to 1945. There are two mainlines of analysis: (1) The transformation of an agricultural practise of peasants into an academic discipline of scientists and (2) the importance of political arguments for this process of scientification. Most of the time Wieland's methods to present his thesis are exemplary: either as biographies or as breeding project histories. So he can write about a great diversity of aspects; but from his point of view – the discipline history as applied science – he cannot show the great importance of economic forces controlling plant breeding. This short article will not diminish the high value of Wieland's book. My aim is only to outline some desiderata for a history of plant breeding which is not yet written.  相似文献   
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Herding and farming coexisted in Central Asia for several thousand years as main options of preindustrial economic production. The relationship between people practicing different variants of these modes of subsistence is known to have been dynamic. Among the many possible explanations, we explore this dynamic by modeling mechanisms that connect aggregate decisions to land use patterns. Within the framework of the SimulPast project, we show here the results from step 1 of our modeling program: the Musical Chairs Model. This abstract agent-based model describes a mechanism of competition for land use between farming and herding. The aim is the exploration of how mobility, intensity, and interdependence of activities can influence land use pattern. After performing a set of experiments within the framework of this model, we compare the implications of each condition for the corroboration of specific land use patterns. Some historical and archaeological implications are also discussed. We suggest that the overall extension of farming in oases can be explained by the competition for land use between farming and herding, assuming that it develops with little or no interference of climatic, geographical, and historical contingencies.  相似文献   
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For the past four years, the Fund for Peace has ranked the Central African Republic, Somalia and South Sudan as the ‘most fragile states’ in the world, in its annual Fragile States Index (FSI). The three countries’ almost identical scores suggest comparability; however, critics raise concerns about the FSI's data aggregation methods, and its conflation of causes and consequences. This article treads the uncharted path of unpacking the empirical realities that hide behind FSI indicators. Drawing on data collected during field research in the three states, the authors investigate three security indicators (security apparatus, factionalized elites, and external intervention) and propose an alternative, qualitative appreciation. Each country's fragility is based on how security forces, elites and interventions evolved over time and installed themselves differently in each region of the country. The qualitative assessment presented here shows that not every indicator matters in all cases at all times or throughout the country. Most crucially, the authors unveil enormous differences between and within the FSI's three ‘most fragile states’. Such variations call for better‐adapted and more flexible intervention strategies, and for quantitative comparisons to be qualitatively grounded.  相似文献   
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In recent years, the strategic role certain metals play is seen as central to the geopolitics promulgated by state agents in the North. While a switch to renewable energy and an increase in energy efficiency might be instrumental to reducing dependence on fossil energy, it increases dependence on metals. This paper starts from an analysis of the likely availability of metals in the near future and then proceeds to investigate political concerns raised by considering the geological fundamentals of social development at the peripheries of the capitalist world‐system. The inequality of metal stocks, future metal requirements and the ensuing political challenges are investigated, taking copper as an example. The final section is dedicated to the discussion of regulatory challenges in view of multiple constraints on metal extraction. This section also highlights the preconditions of a socially legitimate transition to a renewable energy system in the coming period of socio‐ecological transformation.  相似文献   
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This paper presents the preliminary results of a survey project which is being carried out in the small village of Fatschenbrunn, in Lower Franconia, Germany. The project combines archaeological, historical geographical, botanical, geological and pedological data to reconstruct the farming regimes and land use in the late medieval and post-medieval era. Although the project is still on-going, the collected data allows the formulation of hypotheses on the formation of fertile agricultural soils through long-term human intervention in the past.  相似文献   
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