Silk, Regional Rivalry, and the Impact of the Port Openings in Nineteenth Century Japan

The centre of economic activities in Japan was once in western Japan. Since the mid-nineteenth century, however, economic activities within Japan have been continuously shifting towards the east side of the country including Tokyo. Conventional wisdom associates the end of the Tokugawa feudal regime with this eastward shift. By applying a new economic geography model to the silk economy of Japan in the nineteenth century, this paper explains why the majority of industrial activities located initially in western Japan, and offers an alternative economic explanation for the eastward shift as an impact of the port openings in 1859.International trade, economic geography, Japan, silk trade

Trade liberalization and the modern metropolis

What is the impact of international trade on cities and rural areas within a country? Existing studies on this topic are based on new economic geography models, which focus on the effect of international trade on the change in the balance between agglomeration and dispersion forces of the manufacturing firms. Recent studies, however, suggest that large cities today can be characterized as specializing in providing business services to host corporate headquarters, rather than as agglomeration of manufacturing. This paper tries to answer the same question by modelling a modern city that provides business services to host corporate headquarters, and argues that the city is likely to grow larger with trade liberalization.Trade liberalization, city, spatial organization of firms

Learning Visual Categories based on Probabilistic Latent Component Models with Semi-supervised Labeling

This paper proposes a learning method of object andscene categories based on probabilistic latent component modelsin conjunction with semi-supervised object class labeling. In thismethod, a set of object segments extracted from scene images ofeach scene category is firstly clustered by the probabilistic latentcomponent analysis with the variable number of classes, next theprobabilistic latent component tree is generated as a classificationtree of all the object classes of all the scene categories, andthen object classes are incrementally labeled by propagatingprior scene category labels and posterior object category labelsgiven to representative object instances of some object classes asteaching signals. Through experiments by using images of pluralcategories in an image database, it is shown that the methodworks effectively in learning a labeled object category tree andobject category composition of scene categories and achieves highperformance for object and scene recognition

Quiet Mind

N

Isobutanol production from cellobionic acid in Escherichia coli.

BackgroundLiquid fuels needed for the global transportation industry can be produced from sugars derived from plant-based lignocellulosics. Lignocellulosics contain a range of sugars, only some of which (such as cellulose) have been shown to be utilizable by microorganisms capable of producing biofuels. Cellobionic acid makes up a small but significant portion of lignocellulosic degradation products, and had not previously been investigated as an utilizable substrate. However, aldonic acids such as cellobionic acid are the primary products of a promising new group of lignocellulosic-degrading enzymes, which makes this compound group worthy of study. Cellobionic acid doesn't inhibit cellulose degradation enzymes and so its inclusion would increase lignocellulosic degradation efficiency. Also, its use would increase overall product yield from lignocellulose substrate. For these reasons, cellobionic acid has gained increased attention for cellulosic biofuel production.ResultsThis study describes the discovery that Escherichia coli are naturally able to utilize cellobionic acid as a sole carbon source with efficiency comparable to that of glucose and the construction of an E. coli strain able to produce the drop-in biofuel candidate isobutanol from cellobionic acid. The gene primarily responsible for growth of E. coli on cellobionic acid is ascB, a gene previously thought to be cryptic (expressed only after incurring specific mutations in nearby regulatory genes). In addition to AscB, the ascB knockout strain can be complemented by the cellobionic acid phosphorylase from the fungus Neurospora crassa. An E. coli strain engineered to express the isobutanol production pathway was successfully able to convert cellobionic acid into isobutanol. Furthermore, to demonstrate potential application of this strain in a sequential two-step bioprocessing system, E. coli was grown on hydrolysate (that was degraded by a fungus) and was successfully able to produce isobutanol.ConclusionsThese results demonstrate that cellobionic acid is a viable carbon source for biofuel production. This work suggests that with further optimization, a bacteria-fungus co-culture could be used in decreased-cost biomass-based biofuel production systems