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51.
Why at this particular historical moment has there emerged a rousing interest in the potential contribution of diasporas to the development of migrant sending states and why is this diaspora turn so pervasive throughout the global South? The central premise of this paper is that the rapid ascent of diaspora‐centred development cannot be understood apart from historical developments in the West's approach to governing international spaces. Once predicated upon sovereign power, rule over distant others is increasingly coming to depend upon biopolitical projects which conspire to discipline and normalize the conduct of others at a distance so as to create self‐reliant and resilient market actors. We argue that an age of diaspora‐centred development has emerged as a consequence of this shift and is partly constitutive of it. We develop our argument with reference to Giorgio Agamben's “Homo Sacer” project and in particular the theological genealogy of Western political constructs he presents in his book The Kingdom and the Glory (2011). We provide for illustration profiles of three projects which have played a significant role in birthing and conditioning the current diaspora option: the World Bank's Knowledge for Development Programme (K4D); the US‐based International Diaspora Engagement Alliance (IdEA); and the EU/UN Joint Migration and Development Initiative Migration4Development project (JMDI‐M4D). Drawing upon economic theology, we make a case for construing these projects as elements of the West's emerging Oikonomia after the age of empire.  相似文献   
52.
Structure‐ and tectonic‐related gas migration into Ordovician sandstone reservoirs and its impact on diagenesis history were reconstructed in two gas fields in the Sbaa Basin, in SW Algeria. This was accomplished by petrographical observations, fluid inclusion microthermometry and stable isotope geochemistry on quartz, dickite and carbonate cements and veins. Two successive phases of quartz cementation (CQ1 and CQ2) occurred in the reservoirs. Two phase aqueous inclusions show an increase in temperatures and salinities from the first CQ1 diagenetic phase toward CQ2 in both fields. Microthermometric data on gas inclusions in quartz veins reveal the presence of an average of 92 ± 5 mole% of CH4 considering a CH4‐CO2 system, which is similar to the present‐day gas composition in the reservoirs. The presence of primary methane inclusions in early quartz overgrowths and in quartz and calcite veins suggests that hydrocarbon migration into the reservoir occurred synchronically with early quartz cementation in the sandstones located near the contact with the Silurian gas source rock at 100–140°C during the Late Carboniferous period and the late Hercynian episode fracturing at temperatures between 117 and 185°C, which increased in the NW‐direction of the basin. During the fracture filling, three main types of fluids were identified with different salinities and formation temperatures. A supplementary phase of higher fluid temperature (up to 226°C) recorded in late quartz, and calcite veins is related to a Jurassic thermal event. The occurrence of dickite cements close to the Silurian base near the main fault areas in both fields is mainly correlated with the sandstones where the early gas was charged. It implies that dickite precipitation is related to acidic influx. Late carbonate cements and veins (calcite – siderite – ankerite and strontianite) occurred at the same depths resulting from the same groundwater precipitation. The absence of methane inclusions in calcite cements result from methane flushing by saline waters.  相似文献   
53.
F. H. Weinlich 《Geofluids》2014,14(2):143-159
The ascent of magmatic carbon dioxide in the western Eger (Oh?e) Rift is interlinked with the fault systems of the Variscian basement. In the Cheb Basin, the minimum CO2 flux is about 160 m3 h?1, with a diminishing trend towards the north and ceasing in the main epicentral area of the Northwest Bohemian swarm earthquakes. The ascending CO2 forms Ca‐Mg‐HCO3 type waters by leaching of cations from the fault planes and creates clay minerals, such as kaolinite, as alteration products on affected fault planes. These mineral reactions result in fault weakness and in hydraulically interconnected fault network. This leads to a decrease in the friction coefficient of the Coulomb failure stress (CFS) and to fault creep as stress build‐up cannot occur in the weak segments. At the transition zone in the north of the Cheb Basin, between areas of weak, fluid conductive faults and areas of locked faults with frictional strength, fluid pressure can increase resulting in stress build‐up. This can trigger strike‐slip swarm earthquakes. Fault creep or movements in weak segments may support a stress build‐up in the transition area by transmitting fluid pressure pulses. Additionally to fluid‐driven triggering models, it is important to consider that fluids ascending along faults are CO2‐supersaturated thus intensifying the effect of fluid flow. The enforced flow of CO2‐supersaturated fluids in the transitional zone from high to low permeability segments through narrowings triggers gas exsolution and may generate pressure fluctuations. Phase separation starts according to the phase behaviour of CO2‐H2O systems in the seismically active depths of NW Bohemia and may explain the vertical distribution of the seismicity. Changes in the size of the fluid transport channels in the fault systems caused, or superimposed, by fault movements, can produce fluid pressure increases or pulses, which are the precondition for triggering fluid‐induced swarm earthquakes.  相似文献   
54.
This paper addresses the motivations underlying migration decision-making in the case of young university graduates returning to their rural home region in Switzerland. Empirical results show the joint role of social ties, living environment, and job opportunities, although the weight given to each of these factors varies between graduates. Some strategies used by the graduates to cope with a limited labour market are furthermore identified. I argue that internal migrations are far from being the sole consequence of labour market conditions and that a greater appreciation of non-economic issues is needed.  相似文献   
55.
Migration theories often ignore the role that states play in stimulating migration through public assistance policies. Using the case of Mexico, this article explores the role of the state as a migrant‐producing actor by examining the relationship between migration and social assistance policies in the form of monetary cash transfers. It argues that direct, unconditional cash transfers, like those provided by agricultural programs such as Procampo, rather than providing the incentives needed to retain individuals in their home country, may instead be providing the resources needed to migrate, particularly if the amount of the transfer is insufficient to spur investment. Instead of discouraging migration by enhancing economic opportunities and reducing poverty, such policies can actually make it easier and more appealing for its beneficiaries to migrate.  相似文献   
56.
Drawing on ethnographic and interview research conducted in Scotland, South Australia and New South Wales, Australia, I attempt to frame the cultural, social and geographical networks created by the people who follow fish (primarily commercial fishers). My account is constructed through a ‘self-conscious storying’ (Whatmore 2008) deployed by geographers working in a more-than-human perspective. Although I find much to inspire from this approach, throughout this article the question that nags at me is how to account for women within a materialist more-than-human framework, and how to articulate a feminist politics within this epistemological and methodological space. I try to avoid admonitions about what should be done and to advance or to model an embodied glimpse of what such a politics might be.  相似文献   
57.
Knowledge and science transfer – introductory remarks. The article presents introductory remarks on the historical study of knowledge and science transfer. Discussion focuses initially on the reasons for speaking of knowledge transfer and not only about science transfer, and the relations of this topic to current research in general history on cultural transfer. Multiple levels of knowledge / science transfer are then discussed, specifically: (1) transfer by means of migration or other movement of people across geographic boundaries; (2) scientific changes related to the transfer of objects (such as plant specimens or instruments) across continents or disciplines; (3) knowledge or science transfer in practical contexts. Addressed throughout is the problematic character of the concept of transfer itself. The author suggests that users of this concept often presuppose a static conception of scientific and cultural contents being more or less successfully transferred; more interesting, however, are the changes in science and culture conditioned or caused by the migration of individuals as well as the transfer of culture by other means.  相似文献   
58.
李伏明 《史学月刊》2006,(10):65-72
明清时期,松江府是全国的棉纺织业中心。从劳动生产率、劳动时间和劳动力数量等角度考察,明代晚期,松江府棉布产量最多为1575万匹,外销量最多为1305万匹;清代中叶产量最多为3000万匹,外销量在2600万匹左右。明代“松江棉布,衣被天下”,只是市场有效需求不足的结果。清代松江棉布销售区域大大压缩,并不是市场竞争的结果,而是基于其生产能力、运输成本以及与外地经济联系的结果。  相似文献   
59.
Economic globalisation has led to a huge increase in demand for food, goods and services by expanding urban middle class populations. These demands cause environmental changes that in turn feed back upon the urban environment and human population. While the global changes are well researched, the cumulative significance of local environmental changes is less well known. Yet, the local changes may have greater impact on the decisions which individuals make that affect soil erosion and land degradation. People respond to family circumstances and to local economic opportunities in ways that most suit the needs of their families and households. Several demonstration projects that were not adopted offer lessons in understanding how people make their land‐use decisions. An understanding of people's past experiences, present needs and views of the future helps those seeking to improve environmental management to promote policies and actions that are likely to succeed by being acceptable to those involved.  相似文献   
60.
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