This paper develops a two-gene, single fitness peak model for determining the equilibrium distribution of genotypes in a unicellular population which is capable of genetic damage repair. The first gene, denoted by sigma(via), yields a viable organism with first-order growth rate constant k>1 if it is equal to some target "master" sequence sigma(via,0). The second gene, denoted by sigma(rep), yi...

As E. Bromet points out, the current situation in Japan is the result of a triplet of catastrophes. The initial catastrophe, the earthquake itself, caused a certain amount of damage to buildings, but accounted for less than 10% of deaths. The second catastrophe of the tsunami swept away seashore areas and resulted in tremendous loss of life and property. The third and ongoing catastrophe, the n...

The G2 DNA damage checkpoint is activated by genotoxic agents and is particularly important for cancer therapies. Overriding the checkpoint can trigger precocious entry into mitosis, causing cells to undergo mitotic catastrophe. But some checkpoint-abrogated cells can remain viable and progress into G1 phase, which may contribute to further genome instability. Our previous studies reveal that t...

This paper is the first attempt to fit a stochastic cusp catastrophe model to stock market data. We show that the cusp catastrophe model explains the crash of stock exchanges much better than other models. Using the data of U.S. stock markets we demonstrate that the crash of October 19, 1987, may be better explained by cusp catastrophe theory, which is not true for the crash of September 11, 20...

In light of climate change and other global threats, policy commentators sometimes urge that society should be more concerned about catastrophes. This paper reflects on what society’s attitude toward low-probability, high-impact events is, or should be. We first argue that catastrophe risk can be conceived of as a spread in the distribution of losses. Based on this conception, we review studies...

Microtubules are dynamic polymers of αβ-tubulin that have essential roles in chromosome segregation and organization of the cytoplasm. Catastrophe-the switch from growing to shrinking-occurs when a microtubule loses its stabilizing GTP cap. Recent evidence indicates that the nucleotide on the microtubule end controls how tightly an incoming subunit will be bound (trans-acting GTP), but most cur...

RNA viruses evolve rapidly. One source of this ability to rapidly change is the apparently high mutation frequency in RNA virus populations. A high mutation frequency is a central tenet of the quasispecies theory. A corollary of the quasispecies theory postulates that, given their high mutation frequency, animal RNA viruses may be susceptible to error catastrophe, where they undergo a sharp dro...

Mitotic catastrophe, a form of cell death resulting from abnormal mitosis, is a cytotoxic death pathway as well as an appealing mechanistic strategy for the development of anti-cancer drugs. In this study, 6-bromine-5-hydroxy-4-methoxybenzaldehyde was demonstrated to induce DNA double-strand break, multipolar spindles, sustain mitotic arrest and generate multinucleated cells, all of which indic...

We give a brief description of catastrophe theory, and of its applications; to my view, it is a fundamentally qualitative, interpretative theory, and, by itself, it has no ability to predict. Examples are given of interpretations of singularities in statistics and in geophysics (plate tectonics). It is perhaps ironical that I am now assessing the importance of such ideas and theories as structu...

Recent disasters and historical insurance payouts have triggered renewed interest in how firms manage their left-tail exposure. Using a unique dataset of fully described insurance policies purchased by large U.S. firms, we provide the first consistent estimates of premium elasticity of corporate demand for insurance for both catastrophe and noncatastrophe risks. We do so by combining this datas...