We investigate the algorithmic and implementation issues related to the eeective and eecient use of lifted cover inequalities and lifted GUB cover inequalities in a branch-and-cut algorithm for 0-1 integer programming. We have tried various strategies on several test problems and we identify the best ones for use in practice. Branch-and-cut, with lifted cover inequalities as cuts, has been used...

To support investigations of flood tolerance occurring at a field-based research facility, changes in soil volumetric water content, temperature, redox potential, dissolved oxygen content, and pH over the course of flood events were monitored. Electronic sensors connected to dataloggers for continuous monitoring of these parameters were installed, and soil redox potential and pH were also monit...

The small clusters of cells scattered in the pancreas and discovered by Langerhans in 1869, currently known as the islets of Langerhans, are at the centre of the pathology of diabetes. Today they appear as sophisticated micro-organs in which various cell types function in a remarkably co-ordinated manner. Until recently, most of the interest has been centred on the β-cells, which synthesise, st...

Unger, Leon (University of Illinois, Urbana), and R. D. DeMoss. Action of a proline analogue, l-thiazolidine-4-carboxylic acid, in Escherichia coli. J. Bacteriol. 91:1556-1563. 1966.-The effect of the proline analogue, l-thiazolidine-4-carboxylic acid (thioproline), on growth, and its relation to the metabolic function of proline in protein synthesis in Escherichia coli K-12, has been studied. ...

Gap junctions represent a ubiquitous and integral part of multicellular organisms, providing the only conduit for direct exchange of nutrients, messengers and ions between neighboring cells. However, at the molecular level we have limited knowledge of their endogenous permeants and selectivity features. By probing the accessibility of systematically substituted cysteine residues to thiol blocke...

In this paper we gather several improvements in the field of exact and approximate exponential-time algorithms for the BANDWIDTH problem. For graphs with treewidth t we present a O(n2) exact algorithm. Moreover for the same class of graphs we introduce a subexponential constant-approximation scheme – for any α > 0 there exists a (1 + α)-approximation algorithm running in O(exp(c(t + √ n/α) log ...

Common bean (Phaseolus vulgaris L.) is an important legume, useful for its high protein and dietary fiber. The fungal pathogen Uromyces appendiculatus (Pers.) Unger can cause major loss in susceptible varieties of the common bean. The Ur-3 locus provides race specific resistance to virulent strains or races of the bean rust pathogen along with Crg, (Complements resistance gene), which is requir...

This paper discusses the implications of organizational control on the race for economic leadership in merchant empires. Poor organizations have reduced incentives to invest, which in turn stifle technological improvements making leaders lag behind new entrants. Portugal’s large ships carried more merchandize and were more fitting of the monarch’s grandiose preferences, but they also were more ...

In the last decade, technical and logistic systems became more and more specialised, complex and in most cases globally distributed. Already today, it is not possible to oversee or control them from any centralised instance. Nevertheless, from the modelling point of view and their mathematical background those networks seem to have a lot in common. The author gives a comparison of urban traffic...

Factors have been isolated from the central nervous system of the stick insect, Carausius morosus, which affect the rate of secretion of the Malpighian tubules (Gersch et al. i960; Unger, 1965; Vietinghoff, 1967), but it has not yet been shown that these factors are of physiological importance in vivo. There is, however, an accumulation of stainable material in the corpora cardiaca of Carausius...