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Algae have traditionally been included in the group Cryptogamae ('hidden reproduction'), as opposed to Phanerogamae or Spermatophyta, the Seed Plants. Cryptogamae encompassed both macro- and microalgae, lichens, mosses, and ferns, and have also been referred to as 'Thallophyta', 'non-vascular plants', 'spore plants', seedless or flowerless plants, depending on the criteria used for classification. Microalgae have long been considered among the more primitive and less important organisms representing the plant-like characters of autotrophy and immobility. Reproduction in macroalgae was only observed in the 18th century, but the ability of microalgae to reproduce sexually was not demonstrated until the 19th century in microscopic green filamentous algae. In this chapter, we summarise up-to-date information on sexual reproduction in three major groups of microalgae, the diatoms, dinoflagellates and haptophytes, and discuss its relationship to biodiversity and ecological life cycle strategies. Microalgae obviously constitute the microscopic part of the 'plant-like' world, but they do not deserve being considered lower 'plants', as they exhibit a perplexing diversity of modalities of sexual reproduction (haplontic, haplo-diplontic, diplontic life cycles), compared to the 'higher plants' which appear strikingly uniform and rather limited in their life cycle options.

Four strains of the coccolithophore Emiliania huxleyi (RCC1212, RCC1216, RCC1238, RCC1256) were grown in dilute batch culture at four CO2 levels ranging from ~200 μatm to ~1200 μatm. Growth rate, particulate organic carbon content, and particulate inorganic carbon content were measured, and organic and inorganic carbon production calculated. The four strains did not show a uniform response to carbonate chemistry changes in any of the analysed parameters and none of the four strains displayed a response pattern previously described for this species. We conclude that the sensitivity of different strains of E. huxleyi to acidification differs substantially and that this likely has a genetic basis. We propose that this can explain apparently contradictory results reported in the literature.

We investigate the large baryon number sector of the Einstein-Skyrme model as a possible model for baryon stars. Gravitating hedgehog skyrmions have been investigated previously and the existence of stable solitonic stars excluded due to energy considerations. However, in this paper we demonstrate that by generating gravitating skyrmions using rational maps, we can achieve multi-baryon bound states whilst recovering spherical symmetry in the limit where B becomes large., Comment: 23 pages, 8 figures

In early 1992, Kennecott announced plans to modernize and expand the smelter and refinery located near Salt Lake City, Utah. The project increased the smelter capacity from 150,000 tonnes per year to 280,000 tonnes per year and also increased the refinery capacity from 200,000 tonnes per year to meet smelter output. Total cost of the modernization was $882 million. Part I of this paper outlines the scope of the refinery modernization program and describes the implementation of the new technology used there. The technology is based on polymer concrete cells, thoroughly prepared anodes, stainless steel plating blanks, and highly automated materials handling. In Part II, the hydrometallurgical process chemistry employed at the new Kennecott slimes treatment facility is described. The processing philosophy incorporates three major objectives: very-high firstpass recovery of the valuable metals from the slimes with minimal in-process inventory; minimization of the return of impurity metals (e.g., Pb, Sb, As, and Bi) to the smelter circuit; and complete elimination of pyrometallurgical processing with its potential for environmental abuse and precious metals recycle. In both parts, the unit start-ups and initial operating results are presented.

We present the first examples of cosmological solutions to four-dimensional heterotic models which include an evolving bundle modulus. The particular bundle modulus we consider corresponds to the width of a gauge five brane. As such our solutions can be used to describe the evolution in one of these models after a small instanton transition. We find that certain properties are generic to these solutions, regardless of initial conditions. This enables us to make some definite statements about the dynamics subsequent to a small instanton transition despite the fact that we cannot microscopically describe the process itself. We also show that an effective description of the small instanton transition by a continuous matching of fields and their first derivatives is precluded by the form of the respective low-energy theories before and after the transition., Comment: 16 pages, 3 figures