Targets for the MalI repressor at the divergent Escherichia coliK-12malX-malI promoters

Random mutagenesis has been used to identify the target DNA sites for the MalI repressor at the divergent Escherichia coli K-12 malX-malI promoters. The malX promoter is repressed by MalI binding to a DNA site located from position -24 to position -9, upstream of the malX promoter transcript start. The malI promoter is repressed by MalI binding from position +3 to position +18, downstream of the malI transcript start. MalI binding at the malI promoter target is not required for repression of the malX promoter. Similarly, MalI binding at the malX promoter target is not required for repression of the malI. Although the malX and malI promoters are regulated by a single DNA site for cyclic AMP receptor protein, they function independently and each is repressed by MalI binding to a different independent operator site

Long-range memory and multifractality in gold markets

Long-range correlation and fluctuation in the gold market time series of world's two leading gold consuming countries, namely China and India, are studied. For both the market series during the period 1985-2013 we observe a long-range persistence of memory in the sequences of maxima (minima) of returns in successive time windows of fixed length, but the series as a whole are found to be uncorrelated. Multifractal analysis for these series as well as for the sequences of maxima (minima) is carried out in terms of the multifractal detrended fluctuation analysis (MF-DFA) method. We observe a weak multifractal structure for the original series that is mainly originated from the fat-tailed probability distribution function of the values, and the multifractal nature of the original time series is enriched into their sequences of maximal (minimal) returns. A quantitative measure of multifractality is provided by using a set of "complexity parameters".Comment: 21 pages, 10 figures, 2 table

The Role of Institutional Environments on Technical Efficiency: A Comparative Stochastic Frontier Analysis of Cotton Farmers in Benin, Burkina Faso, and Mali

This paper examines the role of institutional environments on cotton farmer technical efficiency scores in Benin, Burkina Faso, and Mali using a stochastic frontier production approach. First, the key institutional changes that have occurred with the recent market-oriented reforms are discussed. Then, farm efficiency per country is measured using cross-sectional data collected by the Cotton Sector Reform Project of the Africa, Power, and Politics Programme in 2009. Results from a one-stage estimation procedure suggest that while no technical inefficiency exists in Benin, an average technical efficiency of 69% and 46% is found in Burkina Faso and Mali, respectively. Agricultural development policies focusing on reducing the inefficiency at the farm level in Mali and Burkina Faso should be adopted; whereas policies designed to shift outward the production frontier seem more appropriate in Benin. Interestingly, institutional environment factors explaining variations in efficiency scores differ across countries. In Mali, farms that are food secure and that cultivate more hectares of cereals are more technically efficient in producing cotton. In contrast, Burkinabe farmers who are dissatisfied with the management of their producer organizations are more technically efficient. To be successful, efforts to promote efficiency would have to work in concert with the local realities in each country.Cotton, Technical Efficiency, Institutional Changes, Reforms, Benin, Burkina Faso, Mali, Agricultural and Food Policy, Consumer/Household Economics, Crop Production/Industries, Institutional and Behavioral Economics, International Development, Production Economics,

GreenPhylDB v2.0: An improved database for plant functional genomics

Poster presented at 2009 Annual Research Meeting of the Generation Challenge Programme. Bamako (Mali), 20-23 September 200