The evolution of knowledge networks has recently received a lot of attention from researchers. Empirical studies have shown that different types of proximities and network structural properties pla...

Western research has shown that a shortage of living space is associated with poor psychological well-being. By contrast, norms and practices of extended family co-residence, collectivist social or...

Dis/articulating producers, markets, and regions: new directions in critical studies of commodity chains In 2008 Werner and Bair proposed a 'disarticulations perspective' as an intervention into the commodity chains and production networks literatures in sociology, geography, and development studies (Bair and Werner, 2011a). (1)While these literatures effectively called our attention to the dynamics of transnational network relations, and especially to the forms of governance through which commodity circuits are coordinated, we (Bair and Werner) argued that extant chain frameworks suffered from an empirical and theoretical bias towards the study of the incorporation of people and places into these circuits.This 'inclusionary bias' results from our tendency, as researchers, to follow the chain, in effect chasing capital to the newest frontier of a production network.Such an approach, we argued, gives short shrift to the uneven geographies of capitalism, and how these geographies shape, and are shaped by, production networks.Our intervention proposed displacing the departure point of commodity chain analysis from network-type models of interfirm transactions to the relationship between global networks and the patterned and contingent reproduction of uneven development.Thus, rather than focusing on the consequences of incorporation into a commodity chain, we wanted instead to ask what are the conditions that enable commodity circuits to form and reform over time.Originally, the commodity chain construct was deployed by world-systems theorists to chart the expansion of a worldwide division of labor.Although we see our project as an extension of this research tradition, we also conceptualize the commodity chain somewhat differently.Rather than an advancing frontier that proceeds by incorporating territorial and social relations inside a hierarchical core-periphery structure of global capitalism, for us the commodity chain is a constantly shifting boundary that demarcates an outside within and reproduces uneven relations at a variety of scales.Influenced by Stuart Hall's notion of articulation developed in the 1980s and more recent literature on primitive accumulation, we proposed the concept of disarticulations to highlight the instabilities, disruptions, and provisional outsides of global production networks.Specifically, we wanted to theorize the significance of these processes for the formation and ongoing restructuring of commodity circuits.The timing of our intervention was not surprising.Uneven development and, in particular, the relationship between capitalist processes and their constitutive outsides has emerged decisively on the agenda of critical social sciences in the last decade.In the wake of the ongoing restructuring of regimes of capitalist accumulation, we have seen renewed attention given to a set of empirically pervasive, but undertheorized, processes of exclusion from and marginalization within capitalist relations.The concrete expression of these processes includes volatile shifts in the geography of production; the concomitant de/revaluation of labor; iterative, often violent, forms of dispossession; and everyday struggles over value through which subjects navigate their own reproduction as workers, managers, farmers, traders, and 'surplus-ed' populations.Our notion of disarticulations then seeks to better understand these forms of exclusion and marginalization in order to rethink the capitalist (1) The concept was developed by Bair and Werner in a set of themed panels at the 2008 meeting of the Association of American Geographers, and subsequently published as a theme issue of Environment and Planning A in 2011 (volume 43, number 5).

Air transport has become a vital component of the global economy. However, greenhouse-gas emissions from this sector have a significant impact on global climate, being responsible for over 3.5% of all anthropogenic radiative forcing. Also, the accrued visibility of aircraft emissions greatly affects the public image of the industry. In this context, incentive-based regulations, in the form of price or quantity controls, can be envisaged as alternatives to mitigate these emissions. The use of environ- mental charges in air transport, and the inclusion of the sector in the European Union Emissions Trading Scheme (EU ETS), are considered under a range of scenarios. The impacts of these measures on demand are estimated, and results suggest that they are likely to be minimalomainly due to the high willingness to pay for air transport. In particular, in the EU ETS scenario currently favoured by the EU, demand reductions are less than 2%. This may not be true in the longer run, for short trips, or if future caps become more stringent. Furthermore, given current estimates of the social cost of CO2 as well as typical EU ETS prices, supply-side abatement would be too costly to be encouraged by these policies in the short term. The magnitude of aviation CO2 emissions in the EU is estimated, both in physical and monetary terms; the results are consistent with Eurocontrol estimates and, for the EU-25, the total social cost of these emissions represents only 0.03% of the region's GDP. It is concluded that the use of multisector policies, such as the EU ETS, is unsuitable for curbing emissions from air transport, and that stringent emission charges or an isolated ETS would be better instruments. However, the inclusion of aviation in the EU ETS has advantages under target-oriented post-2012 scenarios, such as policy-costs dilution, certainty in reductions, and flexibility in abatement allocation. This solution is also attractive to airlines, as it would improve their public image but require virtually no reduction of their own emissions, as they would be fully capable of passing on policy costs to their customers.

This paper suggests a new stated adaptation response format to measure bifurcation points in choice behavior. The method assumes that individuals attach bifurcation points to critical attributes beyond which they change their behavior. Fibonacci numbers are used to identify these bifurcation points efficiently. The resulting data are analyzed using hazard models. The suggested new methodology is illustrated for a sample of 335 travellers who were about to travel by train from Hong Kong to Guangzhou. Respondents were asked to state whether they would retain the choice of train if the travel cost by train were increased by certain amounts, varied according to the Fibonacci principle. Experience with the implementation of the suggested methodology showed that most respondents found the experiment quite interesting. We were able to identify successfully the bifurcation point for all respondents who agreed to participate in the exercise. It took each respondent only a few minutes. The method was thus proved to...