Strong Purcell effect observed in single thick shell CdSe/CdS nanocrystals coupled to localized surface plasmons

High quality factor dielectric cavities designed to a nanoscale accuracy are mostly used to increase the spontaneous emission rate of a single emitter. Here we show that the coupling, at room temperature, between thick shell CdSe/CdS nanocrystals and random metallic films offers a very promising alternative approach. Optical modes confined at the nanoscale induce strong Purcell factors reaching values as high as 60. Moreover the quantum emission properties can be tailored: strong antibunching or radiative biexcitonic cascades can be obtained with high photon collection efficiency and extremely reduced blinking.Comment: 16 pages, 7 figure

Reassessment of pre-industrial fire emissions strongly affects anthropogenic aerosol forcing

Uncertainty in pre-industrial natural aerosol emissions is a major component of the overall uncertainty in the radiative forcing of climate. Improved characterisation of natural emissions and their radiative effects can therefore increase the accuracy of global climate model projections. Here we show that revised assumptions about pre-industrial fire activity result in significantly increased aerosol concentrations in the pre-industrial atmosphere. Revised global model simulations predict a 35% reduction in the calculated global mean cloud albedo forcing over the Industrial Era (1750–2000 CE) compared to estimates using emissions data from the Sixth Coupled Model Intercomparison Project. An estimated upper limit to pre-industrial fire emissions results in a much greater (91%) reduction in forcing. When compared to 26 other uncertain parameters or inputs in our model, pre-industrial fire emissions are by far the single largest source of uncertainty in pre-industrial aerosol concentrations, and hence in our understanding of the magnitude of the historical radiative forcing due to anthropogenic aerosol emissions

Retrospective analysis and modifications of retractor systems for anterior odontoid screw fixation

The authors present an in-depth retrospective analysis of retractor systems for anterior odontoid screw fixation. They discuss various modifications and innovations of such systems and describe their own tubular retractor system, in which a beveled end conformal to the ventral surface of the vertebral column at the C2–3 level is introduced together with an incorporated light source. This new retractor system allows optimal anatomical exposure for controlled odontoid screw placement with improved protection of surrounding vital structures

Challenges of CE

Despite a long pedigree and many positive reports on its use and benefits, concurrent engineering (CE) and its associated research (sub)domains still experience significant development. In this final chapter, a socio-technical framework is applied to classify and analyze challenges identified as part of the foundations, methods and applications discussed in this book. Existing properties and means of CE are abstracted. Subsequently, the main trends and developments in CE research and practice are discussed, followed by expectations for the future. Findings and trends have been identified for strategic issues visible in product requirements and product portfolios, stakeholders including companies involved, multiple functions and disciplines, current and future technologies that are expected to solve at least some of the existing problems, knowledge and skills as brought by people and teams, and structures necessary for making collaboration work, while dealing also with the still very difficult cultural differences. As the chapter shows, CE as a concept is very much alive, requiring even more advanced tools, techniques and methods to contribute to less waste in resources and efforts world-wide and improve quality