BSHM meetings: BMS History of Mathematics Splinter Group

Introduction to abstracts from papers given at BMS History of Mathematics Splinter Group, held 17 April 2007, in Swansea.

Horsham Properties Group Ltd v Clark: possession - mortgagee's right or discretionary remedy?

Comments on the Chancery Division decision in Horsham Properties Group Ltd v Clark on whether a mortgagee's exercise of its contractual right, on the mortgagor falling into arrears, to appoint receivers such that the property could be sold and possession obtained without triggering the court's discretionary powers pursuant to the Administration of Justice Act 1970 s.36 infringed the mortgagor's rights under the European Convention on Human Rights 1950 Protocol 1 art.1. Considers the implications of proposed reforms recasting the mortgagee's right to possession as a discretionary remedy. [From Legal Journals Index]

Evolution of the Diatoms: VIII. Re-Examination of the SSU-Rrna Gene Using Multiple Outgroups and a Cladistic Analysis of Valve Features.

The resolution of the SSU rRNA gene for phylogenetic analysis in the diatoms has been evaluated by Theriot et al. who claimed that the SSU rRNA gene could not be used to resolve the monophyly of the three diatoms classes described by Medlin and Kaczmarska. Although they used both only bolidomonads and heterokonts as outgroups, they did not explore outgroups further away than the heterokonts. In this study, the use of the multiple outgroups inside and outside the heterokonts with the rRNA gene for recovering the three monophyletic clades at the class level is evaluated. Trees with multiple outgroups ranging from only bolidophytes to Bacteria and Archea were analyzed with Bayesian and Maximum Likelihood analyses and two data sets were recovered with the classes being monophyletic. Other data sets were analyzed with non-weighted and weighted maximum parsimony. The latter reduced the number of clades and lengthened branch lengths between the clades. One data set using a weighted analysis recovered the three classes as monophyletic. Taking only bolidophytes as the only outgroup never produced monophyletic clades. Multiple outgroups including many heterokonts and certain members of the crown group radiation recovered monophyletic clades. The three classes can be defined by clear morphological differences primarily based on auxospore ontogeny and envelope structure, the presence or absence of a structure (tube process or sternum) associated with the annulus and the location of the cribrum in those genera with loculate areolae. A cladistic analysis of some of these features is presented and recovers the three classes.