1,202 research outputs found

    Light manipulation principles in biological photonic systems

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    © 2013 Science Wise Publishing and DE GRUYTER.The science of light and colour manipulation continues to generate interest across a range of disciplines, from mainstream biology, across multiple physicsbased fields, to optical engineering. Furthermore, the study of light production and manipulation is of significant value to a variety of industrial processes and commercial products. Among the several key methods by which colour is produced in the biological world, this review sets out to describe, in some detail, the specifics of the method involving photonics in animal and plant systems; namely, the mechanism commonly referred to as structural colour generation. Not only has this theme been a very rapidly growing area of physics-based interest, but also it is increasingly clear that the biological world is filled with highly evolved structural designs by which light and colour strongly influence behaviours and ecological functions.We acknowledge the financial support of DARPA contract W911NF-10-C-0069 and of AFOSR grant FA9550-10-1-0020. We also wish to thank Caroline Pouya, Helen Ghiradella, Radislav Potyrailo, Roy Sambles, Shuichi Kinoshita and Doekele Stavenga for helpful discussions

    A versatile high resolution objective for imaging quantum gases

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    We present a high resolution objective lens made entirely from catalog singlets that has a numerical aperture of 0.36. It corrects for aberrations introduced by a glass window and has a long working distance of 35mm, making it suitable for imaging objects within a vacuum system. This offers simple high resolution imaging for many in the quantum gas community. The objective achieves a resolution of 1.3{\mu}m at the design wavelength of 780nm, and a diffraction-limited field of view of 360{\mu}m when imaging through a 5mm window. Images of a resolution target and a pinhole show quantitative agreement with the simulated lens performance. The objective is suitable for diffraction-limited imaging on the D2 line of all the alkalis by changing only the aperture diameter, retaining numerical apertures above 0.32. The design corrects for window thicknesses of up to 15mm if the singlet spacings are modified

    Transdiaphragmatic Intercostal Hernia Repair in a Patient with Previous Thoracic Surgery

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    A transdiaphragmatic intercostal hernia (TDIH) describes the herniation of abdominal contents through diaphragm and chest wall defects. It has been documented following traumatic injuries as well as after episodes of increased thoracoabdominal pressure. However, those resulting from iatrogenic cause remain uncommon and are less often recorded. We report an iatrogenic TDIH in a patient presenting 39 days after a complicated thoracic procedure, highlighting the surgical technique used for successful hernia reduction, diaphragmatic closure, and rib re-approximation. The case reinforces the possibility of a TDIH occurring as a post-surgical complication. Surgeons should anticipate the potential development of TDIH, particularly after thoracic procedures in patients with significant pre-existing conditions, such as chronic obstructive pulmonary disease (COPD) and cirrhosis. Such clinical awareness should be coupled with apt corrective surgical strategies thereby providing greater opportunity for successful patient recovery

    Thin structured rigid body for acoustic absorption

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    This is the final version of the article. Available from the publisher via the DOI in this record.We present a thin acoustic metamaterial absorber, comprised of only rigid metal and air, that gives rise to near unity absorption of airborne sound on resonance. This simple, easily fabricated, robust structure comprising a perforated metal plate separated from a rigid wall by a deeply subwavelength channel of air is an ideal candidate for a sound absorbing panel. The strong absorption in the system is attributed to the thermo-viscous losses arising from a sound wave guided between the plate and the wall, defining the subwavelength channel.The authors wish to acknowledge financial support from DSTL and QinetiQ

    Human rights and public education

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    This article attempts a contrast to the contribution by Hugh Starkey. Rather than his account of the inexorable rise of human rights discourse, and of the implementation of human rights standards, human rights are here presented as always and necessarily scandalous and highly contested. First, I explain why the UK has lagged so far behind its European neighbours in implementing citizenship education. Second, a comparison with France shows that the latest UK reforms bring us up to 1789. Third, the twentieth-century second-generation social and economic rights are still anathema in the UK. Fourth, the failure to come to terms with Empire and especially the slave trade means that the UK’s attitude to third-generation rights, especially the right of peoples to self-determination, is heavily compromised. Taking into account the points I raise, citizenship education in the UK might look very different

    Going places

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    Journeys. We all make them. Often they take us to exotic places. Sometimes they take us even further. They might take us through time. Or they might take us into a new way of life. There are times too, when we go all over the world and back again only to find that home is, after all, where it’s all happening. This book contains stories about many different types of journey. We hope you will enjoy travelling into it and finding a world that suits you

    What explains the uneven take-up of ISO 14001 at the global level?: a panel-data analysis

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    Since its release in the mid-1990s, close to 37 000 facilities have been certified to ISO 14001, the international voluntary standard for environmental management systems. Yet, despite claims that the standard can be readily adapted to very different corporate and geographic settings, its take-up has been highly geographically variable. This paper contributes to a growing body of work concerned with explaining the uneven diffusion of ISO 14001 at the global level. Drawing from the existing theoretical and empirical literature we develop a series of hypotheses about how various economic, market, and regulatory factors influence the national count of ISO 14001 certifications. These hypotheses are then tested using econometric estimation techniques with data for a panel of 142 developed and developing countries. We find that per capita ISO 14001 counts are positively correlated with income per capita, stock of foreign direct investment, exports of goods and services to Europe and Japan, and pressure from civil society. Conversely, productivity and levels of state intervention are negatively correlated. The paper finishes by offering a number of recommendations to policymakers concerned with accelerating the diffusion of voluntary environmental standards
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