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Objectives-To determine (a) whether doctors involved in the process of emergency surgical admission could agree about which patients should be admitted, (b) whether there were consistent differences between doctors in different speciality groups, and (c) whether these opinions were greatly influenced by nonclinical factors. Design-Independent assessment of summarised case histories by three "expert" clinicians (two consultant surgeons and one general practitioner (GP)), by a group of 10 GPs, and by a group of 10 in the organisation and funding ofacute surgical services, changes in public attitudes, and changes in medical attitudes.The last of these is clearly pivotal, since doctors have the responsibility of defining whether acute hospital admissions are necessary or not. We do not know whether there is general agreement within the profession about what constitutes a "necessary" admission, but such a consensus is clearly necessary to allow rational analysis of the problems posed by increasing numbers of such admissions. Surgical emergency admissions have received less attention than medical emergencies, but the rise in numbers appears to affect all specialty groups. We therefore set out to determine the attitudes of the doctors directly involved in admitting surgical patients to hospital. The training and clinical role of different types of doctors may lead to differences of opinion about the appropriate management of patients presenting with acute "surgical" conditions. We therefore asked whether doctors involved in the process of emergency surgical admission could agree about which patients should be admitted, whether there were consistent differences between doctors in different speciality groups, and whether these opinions were greatly influenced by non-clinical factors. To answer these questions we asked doctors involved in the emergency admission process to evaluate case summaries of a series of real emergency admissions to the Fazakerley surgical unit.

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Solid-state lighting relies on the conversion of electricity to visible white light using solid materials. By taking advantage of direct electricity-to-light conversion rather than processes in which light is the by-product of another conversion, as with traditional incandescent and fluorescent lighting, it promises unprecedented, near-100% conversion efficiency.Today's solid-state lighting technology, however, requires a fifteen-fold improvement to achieve such conversion efficiencies. The reason is that, to become the standard light source of the 21st century, conversion efficiency must be improved while simultaneously achieving low cost and "high quality" (a human visual experience similar to that provided by sunlight).The front cover is an artistic stylization of a "chromaticity diagram," a common tool that can be used to describe how colors can combine to create the human visual impression of white.White can be produced from as few as two colors, but "highquality" white requires many (e.g., red, yellow, green, and blue) colors. The tessellation overlaid on the chromaticity diagram is suggestive of photonic crystals (nanometer-scale periodic modulations of optical materials that can affect the directionality of light), a frontier area of interdisciplinary science being applied to solid-state lighting.This report outlines basic research needs that could enable solid-state lighting to achieve its potential. The research needs support two overarching challenges: (1) fundamental understanding of light-emitting materials and nanostructures leading to solid-state lighting structures rationally designed from the ground up and (2) control of the competing pathways by which electricity is converted into light not heat so that every injected electron produces a useful photon. Successfully addressing these two challenges promises to enable energy-efficient, cost-effective, high-quality white light that will save energy and benefit the environment. BASIC RESEARCH NEEDS FOR SOLID-STATE LIGHTING EXECUTIVE SUMMARYSince fire was first harnessed, artificial lighting has gradually broadened the horizons of human civilization. Each new advance in lighting technology, from fat-burning lamps to candles to gas lamps to the incandescent lamp, has extended our daily work and leisure further past the boundaries of sunlit times and spaces. The incandescent lamp did this so dramatically after its invention in the 1870s that the light bulb became the very symbol of a "good idea."Today, modern civilization as we know it could not function without artificial lighting; artificial lighting is so seamlessly integrated into our daily lives that we tend not to notice it until the lights go out. Our dependence is even enshrined in daily language: an interruption of the electricity supply is commonly called a "blackout."This ubiquitous resource, however, uses an enormous amount of energy. There is ample room for reducing this energy and environmental cost. The artificial lighting we take for granted is extremely inefficient primarily because a...