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Introduction  Proposed landmarks to predict the anatomical location and trajectory of the sigmoid sinus have varying degrees of reliability. Even with neuronavigation technology, landmarks are crucial in planning and performing complex approaches to the posterolateral skull base. By combining two major dependable structures—the asterion (A) and transverse process of the atlas (TPC1)—we investigate the A-TPC1 line in relation to the sigmoid sinus and in partitioning surgical approaches to the region. Methods  We dissected six cadaveric heads (12 sides) to expose the posterolateral skull base, including the mastoid and suboccipital bone, TPC1 and suboccipital triangle, distal jugular vein and internal carotid artery, and lower cranial nerves in the distal cervical region. We inspected the A-TPC1 line before and after drilling the mastoid and occipital bones and studied the relationship of the sigmoid sinus trajectory and major muscular elements related to the line. We retrospectively reviewed 31 head and neck computed tomography (CT) angiograms (62 total sides), excluding posterior fossa or cervical pathologies. Bone and vessels were reconstructed using three-dimensional segmentation software. We measured the distance between the A-TPC1 line and sigmoid sinus at different levels: posterior digastric point (DP), and maximal distances above and below the digastric notch. Results  A-TPC1 length averaged 65 mm and was posterior to the sigmoid sinus in all cadaver specimens, coming closest at the level of the DP. Using the transverse-asterion line as a rostrocaudal division and skull base as a horizontal plane, we divided the major surgical approaches into four quadrants: distal cervical/extreme lateral and jugular foramen (anteroinferior), presigmoid/petrosal (anterosuperior), retrosigmoid/suboccipital (posterosuperior), and far lateral/foramen magnum regions (posteroinferior). Radiographically, the A-TPC1 line was also posterior to the sigmoid sinus in all sides and came closest to the sinus at the level of DP (mean, 7 mm posterior; range, 0–18.7 mm). The maximal distance above the DP had a mean of 10.1 mm (range, 3.6–19.5 mm) and below the DP 5.2 mm (range, 0–20.7 mm). Conclusion  The A-TPC1 line is a helpful landmark reliably found posterior to the sigmoid sinus in cadaveric specimens and radiographic CT scans. It can corroborate the accuracy of neuronavigation, assist in minimizing the risk of sigmoid sinus injury, and is a useful tool in planning surgical approaches to the posterolateral skull base, both preoperatively and intraoperatively. [ABSTRACT FROM AUTHOR]

This article examines cooperative modes of regulation of local economies that in Europe increasingly take the form of concertation (partnership)--i.e. formalized agreement on common goals stated by collective actors with traditionally/potentially contrasting interests. This kind of agreement (`pacts') is increasingly institutionalized; `institutionalization' being the process through which certain behaviours are steadily promoted, required, even made obligatory, by. actors other than those putting them into effect, who demand conformity to their values and beliefs in return for making resources available. The process in question is particularly visible in EU countries, and it can be interpreted both as an opportunity to construct a model of a social Europe and as an opportunity to defend the features of this model that were subject to rapid erosion during the 1990s. Recurrent forms of partnership are: public-private and public-public partnerships; `regionalized' industrial relations; `second-generation' industrial districts; urban strategic planning; and territorial pacts. To order them, a typology is proposed on the basis of the dichotomy between exogenous/endogenous actors/resources. Three main constraints to an effective working of local concertation are then discussed: local presence of `global players'; excessive institutionalization; and lack of adequate implementation structures. Starting from the latter, some working hypotheses are proposed on a new `organizational population', namely, the organizations of local development.

Richard Florida and Patrick Le Galès presented at the beginning of the century two models that were later at the center of the scientific and political debate: the city of the creative class, the European city. After fifteen years the two authors return to their former positions in order to correct them sensibly. Florida recognizes in the evolution of the creative city a dark side made of growing inequality and segregation; Le Galès identifies a growing differentiation of European cities, partially undermining the original model. Following completely independent paths, the two authors seem to agree on the increasing differentiation of cities, the growth of urban inequalities, the possibility of self-correction of the initial models. [ABSTRACT FROM AUTHOR]