Year in review 2006: Critical Care – cardiology

This review summarizes key research papers published in the fields of cardiology and intensive care during 2006 in Critical Care and, where relevant, in other journals within the field. The papers have been grouped into categories: haemodynamic monitoring, vascular access in intensive care, microvascular assessment and manipulation, and impact of metabolic acidosis on outcome

ALL CITIES ARE DIFFERENT: Moving creative workforce research forward to a new specificity

The cultural sector and its workforce are often positioned as economic drivers, and important themes within this discourse have included relationships between the cultural sector and human capital, urban regeneration, community engagement, branding, and image. Little of the research underpinning these arguments has documented the work practices, orientations, attitudes, career trajectories and skill requirements of individual creative workers, and even less has considered the spatially specific nature of labour conditions and career trajectories to produce a differentiated analysis of work and career. What happens within any locality over time will partially result from the changing roles it plays within the broader spatial divisions of labour within which it is emplaced. However, we argue that it is insufficient to claim that all cities are different; rather, there is a need to examine the specificity of work in each location.In this paper, the second in a series that examine specific elements of creative work, we consider spatiality with specific reference to the use of networks. Drawing on a case study of the film and television industries in Perth we raise the possibility of approaching such research by combining the global production network approach, labour process analysis, and research that looks within individual practice

The United Nations Basic Space Science Initiative: The TRIPOD concept

Since 1990, the United Nations is annually holding a workshop on basic space science for the benefit of the worldwide development of astronomy. Additional to the scientific benefits of the workshops and the strengthening of international cooperation, the workshops lead to the establishment of astronomical telescope facilities through the Official Development Assistance (ODA) of Japan. Teaching material, hands-on astrophysics material, and variable star observing programmes had been developed for the operation of such astronomical telescope facilities in an university environment. This approach to astronomical telescope facility, observing programme, and teaching astronomy has become known as the basic space science TRIPOD concept. Currently, a similar TRIPOD concept is being developed for the International Heliophysical Year 2007, consisting of an instrument array, data taking and analysis, and teaching space science.Comment: 8 pages, LaTe

Speed of disentanglement in multi-qubit systems under depolarizing channel

We investigate the speed of disentanglement in the multiqubit systems under the local depolarizing channel, in which each qubit is independently coupled to the environment. We focus on the bipartition entanglement between one qubit and the remaining qubits constituting the system, which is measured by the negativity. For the two-qubit system, the speed for the pure state completely depends on its entanglement. The upper and lower bounds of the speed for arbitrary two-qubit states, and the necessary conditions for a state achieving them, are obtained. For the three-qubit system, we study the speed for pure states, whose entanglement properties can be completely described by five local-unitary-transformation invariants. An analytical expression of the relation between the speed and the invariants is derived. The speed is enhanced by the the three-tangle which is the entanglement among the three qubits, but reduced by the the two-qubit correlations outside of the concurrence. The decay of the negativity can be restrained by the other two negativity with the coequal sense. The unbalance between two qubits can reduce speed of disentanglement of the remaining qubit in the system, even can retrieve the entanglement partially. For the k-qubit systems in an arbitrary superposition of GHZ state and W state, the speed depends almost entirely on the amount of the negativity when k increases to five or six. An alternative quantitative definition for the robustness of entanglement is presented based on the speed of disentanglement, with comparison to the widely studied robustness measured by the critical amount of noise parameter where the entanglement vanishes. In the limit of large number of particles, the alternative robustness of the GHZ-type states is inversely proportional to k, and the one of the W states approaches 1/\sqrt{k}.Comment: 14 pages, 5 figures. to appear in Annals of Physic

Beyond the black box: promoting mathematical collaborations for elucidating interactions in soil ecology

Understanding soil systems is critical because they form the structural and nutritional foundation for plants and thus every terrestrial habitat and agricultural system. In this paper, we encourage increased use of mathematical models to drive forward understanding of interactions in soil ecological systems. We discuss several distinctive features of soil ecosystems and empirical studies of them. We explore some perceptions that have previously deterred more extensive use of models in soil ecology and some advances that have already been made using models to elucidate soil ecological interactions. We provide examples where mathematical models have been used to test the plausibility of hypothesized mechanisms, to explore systems where experimental manipulations are currently impossible, or to determine the most important variables to measure in experimental and natural systems. To aid in the development of theory in this field, we present a table describing major soil ecology topics, the theory previously used, and providing key terms for theoretical approaches that could potentially address them. We then provide examples from the table that may either contribute to important incremental developments in soil science or potentially revolutionize our understanding of plant–soil systems. We challenge scientists and mathematicians to push theoretical explorations in soil systems further and highlight three major areas for the development of mathematical models in soil ecology: theory spanning scales and ecological hierarchies, processes, and evolution

River channel width controls blocking by slow-moving landslides in California's Franciscan melange

This is the final version. Available from European Geosciences Union via the DOI in this record. To explore the sensitivity of rivers to blocking from landslide debris, we exploit two similar geomorphic settings in California's Franciscan mélange where slow-moving landslides, often referred to as earthflows, impinge on river channels with drainage areas that differ by a factor of 30. Analysis of valley widths and river long profiles over ∼19 km of Alameda Creek (185 km2 drainage area) and Arroyo Hondo (200 km2 drainage area) in central California shows a very consistent picture in which earthflows that intersect these channels force tens of meters of gravel aggradation for kilometers upstream, leading to apparently long-lived sediment storage and channel burial at these sites. In contrast, over a ∼30 km section of the Eel River (5547 km2 drainage area), there are no knickpoints or aggradation upstream of locations where earthflows impinge on its channel. Hydraulic and hydrologic data from United States Geological Survey (USGS) gages on Arroyo Hondo and the Eel River, combined with measured size distributions of boulders input by landslides for both locations, suggest that landslide derived boulders are not mobile at either site during the largest floods (>2-year recurrence) with field-measured flow depths. We therefore argue that boulder transport capacity is an unlikely explanation for the observed difference in sensitivity to landslide inputs. At the same time, we find that earthflow fluxes per unit channel width are nearly identical for Oak Ridge earthflow on Arroyo Hondo, where evidence for blocking is clear, and for the Boulder Creek earthflow on the Eel River, where evidence for blocking is absent. These observations suggest that boulder supply is also an unlikely explanation for the observed morphological differences along the two rivers. Instead, we argue that the dramatically different sensitivity of the two locations to landslide blocking is related to differences in channel width relative to typical seasonal displacements of earthflows. A synthesis of seasonal earthflow displacements in the Franciscan mélange shows that the channel width of the Eel River is ∼5 times larger than the largest annual seasonal displacement. In contrast, during wet winters, earthflows are capable of crossing the entire channel width of Arroyo Hondo and Alameda Creek. In support of this interpretation, satellite imagery shows that immobile earthflow-derived boulders are generally confined to the edges of the channel on the Eel River. By contrast, immobile earthflow-derived boulders jam the entire channel on Arroyo Hondo. Our results imply that lower drainage area reaches of earthflow-dominated catchments may be particularly prone to blocking. By inhibiting the upstream propagation of base-level signals, valley-blocking earthflows may therefore promote the formation of so-called “relict topography”.National Science Foundatio

Creative Labour: Towards a Renewed Research Agenda

This article focuses on the role of creative labour, which has figured prominently in narratives of ‘new capitalism’ that promise to change standard employment relations and generate new modes of innovation. To move beyond such broad claims a more detailed picture of the characteristics and dynamics of work and employment of creative workers in different industries and groups is required. In this paper we begin by outlining our theoretical approach based on a combination of global production analysis, labour process analysis and a relational view of territorial networks. We proceed by examining the definitions used to define particular industries and workers as cultural or creative and then review recent analysis of work and employment relations in the cultural sector