Previous efforts to control cellular behaviour have largely relied upon various forms of genetic engineering. Once the genetic content of a living cell is modified, the behaviour of that cell typically changes as well. However, other methods of cellular control are possible. All cells sense and respond to their environment. Therefore, artificial, non-living cellular mimics could be engineered to activate or repress already existing natural sensory pathways of living cells through chemical communication. Here we describe the construction of such a system. The artificial cells expand the senses of Escherichia coli by translating a chemical message that E. coli cannot sense on its own to a molecule that activates a natural cellular response. This methodology could open new opportunities in engineering cellular behaviour without exploiting genetically modified organisms.

To facilitate the construction of cell-free genetic devices, we evaluated the ability of 17 different fluorescent proteins to give easily detectable fluorescence signals in real-time from in vitro transcription-translation reactions with a minimal system consisting of T7 RNA polymerase and E. coli translation machinery, i.e., the PUREsystem. The data were used to construct a ratiometric fluorescence assay to quantify the effect of genetic organization on in vitro expression levels. Synthetic operons with varied spacing and sequence composition between two genes that coded for fluorescent proteins were then assembled. The resulting data indicated which restriction sites and where the restriction sites should be placed in order to build genetic devices in a manner that does not interfere with protein expression. Other simple design rules were identified, such as the spacing and sequence composition influences of regions upstream and downstream of ribosome binding sites and the ability of non-AUG start codons to function in vitro.

As interest shifts from individual molecules to systems of molecules, an increasing number of laboratories have sought to build from the bottom up cellular mimics that better represent the complexity of cellular life. To date there are a number of paths that could be taken to build compartmentalized cellular mimics, including the exploitation of water-in-oil emulsions, microfluidic devices, and vesicles. Each of the available options has specific advantages and disadvantages. For example, water-in-oil emulsions give high encapsulation efficiency but do not mimic well the permeability barrier of living cells. The primary advantage of the methods described herein is that they are all easy and cheap to implement. Transcription-translation machinery is encapsulated inside of phospholipid vesicles through a process that exploits common instrumentation, such as a centrifugal evaporator and an extruder. Reactions are monitored by fluorescence spectroscopy. The protocols can be adapted for recombinant protein expression, the construction of cellular mimics, the exploration of the minimum requirements for cellular life, or the assembly of genetic circuitry.

The strategic mobilization of images, visual metaphors, and other forms of graphical rhetoric has always been central in place promotion. Images of place have assumed even greater importance, however, with the rise of locational tournaments of cities bidding for the "right" to host high-stakes transnational spectacles. In this paper, we adapt Harvey Molotch's pioneering theory of the urban growth machine to illuminate the contemporary enterprise of city bids for the Olympic Games. Taking Vancouver's successful bid for the 2010 Winter Games as a case study, we use a visual methodology framework to analyze the manifest (explicit, surface) and latent (implicit, subtle) visual narrative strategies used to craft a carefully considered representation of the city. Our analysis of the official Bid Questionnaire and the video presentation to the International Olympic Committee documents the sophisticated process by which a city is constructed to embody pristine urban nature, multicultural social harmony, and vibrant local cultures of sport in keeping with the spirit of Olympism. Whether imagined cities like this are effective is irrelevant: cities understand that half of their advertising budget is wasted (they just don't know which half). The expanding symbolic economies of tourism, conventions, and hallmark events require that urban growth machines develop and operate a full suite of image creation machines, each attuned to the real and perceived desires of an elusive transnational audience in a perpetual movable feast of locational consumption. [End Page 24]

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