The fate of prematurely condensed chromosomes (PCC) that are induced following fusion between a mitotic and an interphase cell was studied in the homokaryons of HeLa and 2 glycine-requiring mutants of Chinese hamster ovary cells. The data indicate: (1) the prematurely condensed chromosomes are often incorporated into daughter nuclei of the fused cells and hence they are functionally retained by...

This paper considers the maximum value of the permanent over the class H(m, n) of n × n Hessenberg, (0, 1)-matrices with m 1’s, and shows that among those matrices that attain the maximum value there exists a matrix with a special form. This special form determines the exact value of the maximum permanent on H(m, n) for certain values of m and n.

This final overview draws on the papers selected for this volume and other sources to identify obstacles to sexual behaviour change in the African AIDS epidemic. Limitations to existing interventions and possible new interventions are then discussed. Obstacles to behavioural change are identified as the adherence to the present sexual culture; the refusal of leaders to recognize or come to term...

The sets generated as the long time attractors of “physical” dynamical systems described by ordinary differential equations or discrete evolution equations in the case of maps such as the Hénon map appear to be very complicated, often with unpleasant properties such as the lack of robustness (the parameters leading to chaotic and nonchaotic solution may be intertwined on an arbitrarily small sc...

Computi ng is the science of information processing, and the generation and manipulation of information pervades all aspects of computing. Nevertheless, we feel confident in asserting that information—data and knowledge—is even more important in the Grid environment than in other domains. We make this assertion for two reasons. First, the virtual organizations that define Grid systems are forme...

Modern English approaches the ideal of an isolating language. Open-class items have comparatively few forms, so that many inflectional categories either remain unmarked, or are expressed periphrastically. The inflectional system is particularly simple, even by the standards of a West Germanic language. Regular paradigms contain at most four forms, and the inflectional exponents that distinguish...

A well-constituted plant or animal cell is most certainly equipped with a functional, regulated organization of its impressive array of molecules, and there is no reason to suppose that the coenocytic hypha of a watermold is constructed differently from the cells of other eukaryotes in this regard. Unfortunately, there is a vexatious shortcoming to the collection of facts surrounding the biolog...

The primal-dual method increases the dual variables gradually until some dual constraint becomes tight. Then, the primal variable corresponding to the tight dual constraint is ‘bought’ (or selected), and the process continues till we get a feasible primal solution. Next, we compare the value of the primal solution to the value of the dual solution to get an appropriate approximation factor (or ...