On groups with a class-preserving outer automorphism

In 1911, Burnside asked whether or not there exist groups that have an outer automorphism which preserves conjugacy classes. Two years later he answered his own question by constructing a family of such groups. Using the small group library in MAGMA we determine all of the groups of order n < 512 that possess such an automorphism. Our investigations led to the discovery of four new infinite families of such groups, all of which are 2-groups of coclass 4

Socioeconomic deprivation and age are barriers to the online collection of patient reported outcome measures in orthopaedic patients

Introduction: Questionnaires are used commonly to assess functional outcome and satisfaction in surgical patients. Although these have in the past been administered through written forms, there is increasing interest in the use of new technology to improve the efficiency of collection. The aim of this study was to assess the availability of internet access for a group of orthopaedic patients and the acceptability of online survey completion. Methods: A total of 497 patients attending orthopaedic outpatient clinics were surveyed to assess access to the internet and their preferred means for completing follow-up questionnaires. Results: Overall, 358 patients (72%) reported having internet access. Lack of access was associated with socioeconomic deprivation and older age. Multivariable regression confirmed increased age and greater deprivation to be independently associated with lack of internet access. Out of the total group, 198 (40%) indicated a preference for assessment of outcomes via email and the internet. Conclusions: Internet access was not universal among the patients in our orthopaedic clinic. Reliance on internet collection of PROMs may introduce bias by not including results from patients in older age groups and those from the more deprived socioeconomic groups

Nuclear applications in manned space station

The zirconium hydride reactor, coupled to a thermo-electric or Brayton conversion system, and the Pu 238 isotope/Brayton system, are considered to be the viable nuclear candidates for the modular space station electrical power system. The basic integration aspects of these nuclear electrical power systems are reviewed, including unique requirements imposed by the buildup and incremental utilization considerations of the modular station. Also treated are the various programmatic aspects of nuclear power system design and selection

A critical appraisal of WinEcon and its use in a first‐year undergraduate Economics programme

This is an extended review of WinEcon, a CAL package for introductory economics. Our comments are based on a survey of staff and students involved in the first large‐scale (n = 300+) attempt to integrate WinEcon into a teaching and assessment programme

Testing isomorphism of graded algebras

We present a new algorithm to decide isomorphism between finite graded algebras. For a broad class of nilpotent Lie algebras, we demonstrate that it runs in time polynomial in the order of the input algebras. We introduce heuristics that often dramatically improve the performance of the algorithm and report on an implementation in Magma

The role of the conserved ASP443 and ASP498 residues in the polymerase and RNase H activities of HIV-1 reverse transcriptase

Submiltted in fulfillment of the requirements for the degree of Master of Science in the faculty of Science, University of the Witwatersrand, Johannesburg • Johannesburg 1993.The roles of the highly conserved aspartic acid residues found at positions 443 and 498 within the RNase H domain of Human Immunodeficiency Virus type-1 reverse transcription were investigated by the defined substitution of these residues using site-directed mutagenesis. [Abbreviated Abstract. Open document to view full version]MT201

Groups Acting on Tensor Products

Groups preserving a distributive product are encountered often in mathematics. Examples include automorphism groups of associative and non associative rings, classical groups, and automorphisms of p-groups. While the great variety of such products precludes any realistic hope of describing the general structure of the groups that preserve them, it is reasonable to expect that insight may be gained from an examination of the universal distributive products: tensor products. We give a detailed description of the groups preserving such tensor products over semisimple and semi primary rings, and present effective algorithms to construct generators for these groups. We also discuss applications of our methods to algorithmic problems for which all currently known methods require an exponential amount of work