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The research undertaken was an ethnographic study of a single junior school was founded on the premise that children have considerably more knowledge about ‘citizenship’ and democratic processes than their teachers appreciate or are willing to acknowledge. It was my contention that in developing a citizenship programme and scheme of work in school this should be taken account of to inform, not only the curriculum, but also teaching and learning. My concern was that without doing so, paradoxically, citizenship might have more to do with social control than the intended outcome of empowerment. A key finding of the study was that teachers taught social and moral responsibility rather than rights and that responsibility was inextricably linked to pupils’ behaviour. It also found that much of the information, knowledge and understanding, about democratic processes held by children appeared to be caught rather than taught. The study also showed that teachers taught about ‘safe issues’ whilst avoiding any teaching relating to local, national or world political events that might be contentious or controversial. From the findings a theoretical model for citizenship was developed that shows the relationship between citizenship knowledge, social control, empowerment, and teaching and learning. This study has contributed to the developing understanding of citizenship as it has been implemented in primary schools in England. The evidence suggests that unless teachers take account of pupils’ prior knowledge of citizenship they will by default indeed be teaching for social control rather than empowerment.

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative condition which is almost universally fatal. Some sufferers have an identifiable genetic mutation (<2%), but the majority of cases are sporadic (SALS). There is a body of evidence suggesting involvement of oxidative stress and mitochondrial abnormalities in the pathogenesis of ALS. Mitochondrial function was assessed in remote tissues (muscle, cultured myoblasts, cultured fibroblasts) from patients with ALS and controls. Muscle tissue was examined for histological features consistent with a mitochondrial disorder. Mitochondrial respiratory chain function was measured in mitochondrial homogenates. Mitochondrial protein expression was determined using immunofluorescent antibodies to a mitochondrial DNA (mtDNA)-encoded respiratory chain enzyme subunit with image analysis. MtDNA quantity and quality was assessed using Southern blot and long-range PCR. Analysis of inheritance patterns was performed using a database of familial ALS cases. No mitochondrial abnormalities were identified using these techniques. There was no evidence of anticipation or a sex effect on inheritance. In order to look for a difference in susceptibility to oxidative stress, cell cultures were examined for markers of oxidative damage and apoptosis, following growth with a free radical generating agent (paraquat). These studies demonstrated an increased susceptibility to oxidative damage in patient myoblasts and fibroblasts. This effect was not seen in cybrid studies combining mtDNA from patient platelets with experimental cells devoid of mtDNA (p cells), where no difference in oxidative damage was seen, confirming the absence of a systemic mtDNA abnormality. These results suggest that patients with SALS have an increased systemic sensitivity to oxidative stress which becomes pathological in tissues, such as motor neurons, which are considered to be vulnerable to such stress due to their metabolic activity and structure. This altered sensitivity is due to a factor other than a mitochondrial DNA abnormality, such as a nuclear DNA mutation or an unidentified environmental factor.

Background - Hand intense occupational activities have been associated with an increase in the incidence of carpal tunnel syndrome (CTS). CTS is characterized by an impairment of median nerve function. To date, a dose-response relationship between wrist activity and median nerve performance has not been documented. Since repetitive hand/wrist activity in the workplace has significant implications, it is important to establish a scientific basis for the aetiology of work-related carpal tunnel syndrome. Methods -- In a laboratory environment, twenty-seven clinically confirmed asymptomatic female subjects performed continuous repetitive wrist motion in the flexion-extension plane during which an angle of 120 degrees was subtended about the neutral wrist position. Four levels of wrist activity, corresponding with 0 (static), 22 (Iow), 38 (medium) and 49 (high) repetitions per minute, were prescribed. Wrist motion was recorded using a state-of-the-art 3D electromagnetic tracking system (HumanTRAC). Mathematical descriptors of wrist kinematics, including cycle time, amplitude, angular velocity and angular acceleration, were calculated. Sensory median nerve response to imposed physical stressors was monitored antidromically and recorded using a clinical electroneurometer every ten minutes throughout the simulated work activities. Near-nerve skin temperature was recorded at three sites along the distal sensory branch of the median nerve every twenty minutes. Results - After adjusting for changes in near-nerve skin temperature, a significant within-subject effect of duration of exposure (time) was detected. Sensory median nerve conduction velocity differed statistically by 2.1 ms-1 between the static and high wrist activity conditions after 120 minutes of exposure, signifying adverse effects on nerve conduction that are uniquely attributable to repetitive hand motion. Wrist activity measures of mean angular acceleration presented a highly significant association with nerve performance, where nerve conduction decreased as wrist activity increased. Using regression analysis, a maximum safe wrist-workload exposure limit of 0.91 repetitions per minute is proposed. Limitations of this result are discussed. A biomechanical model is presented to calculate the effect of physical risk factors on tendon forces at the wrist. This model offers a method by which findings of the study can be employed for workplace exposure surveillance and development of ergonomic workstation design recommendations. Conclusions -- Across the study population of clinically asymptomatic female participants, a change in median nerve performance was observed. This significant effect was evoked due to imposed physical stressors. A dose response relationship between work intensity, exposure time and median nerve conduction velocity was demonstrated. The research explored in this thesis presents a foundation for the future development of a "Dynamic Median Nerve Stress Test". This test would involve the performance of a repetitive motion activity of the wrist during which changes in the function of the median nerve are closely monitored. The Dynamic Median Nerve Stress Test might prove to be valuable both as a provocative clinical test as well as an important research tool.

The purpose of this investigation was to study the heterologous expression of soluble methane monooxygenase (sMMO) genes from Methylococcus capsulatus (Bath) and Methylosinus trichosporium OB3b. Using the T7-RNA polymerase expression system, the entire sMMO operon and subclones (constructed using the polymerase chain reaction) were over-expressed in E. coli. Results obtained using the Me. capsulatus (Bath) sMMO operon confirmed previous reports (C. West, G. P. C. Salmond, H. Dalton and 1. C. Murrell (1992). J Gen. Microbial. 138, 1301-1307) that functional expression of protein B and the reductase occurred but the hydroxylase was inactive. Similar results were obtained by expressing the sMMO operon of Ms. trichosporium OB3b in E. coli, using plasmids previously described (D. Jahng and T. K. Wood (1994). Appl. Environ. Microbiol. 60, 2473-2482). Protein B, the reductase and orfY were over-expressed and purified from E. coli using glutathione-Stransferase fusion proteins and affinity chromatography. The expression of sMMO genes from Mc. capsulatus (Bath) and Ms. trichosporium OB3b was studied in Pseudomonas putida. A previous report (D. Jahng and T. K. Wood (1994). Appl. Environ. Microbial. 60, 2473-2482) had suggested that functional expression of sMMO from Ms. trichosporium OB3b was achieved in P. putida Fl. Attempts to repeat this work proved that protein B and the reductase were functionally expressed, but the hydroxylase was inactive. Similar results were obtained for the heterologous expression of the sMMO operon from Mc. capsulatus (Bath) in P. putida. Methanotrophs were used for the heterologous expression of sMMO via two strategies. (1) The expression of sMMO from Mc. capsulatus (Bath) and Ms. trichosporium OB3b was studied in Methylomonas album B08 and Methylocystis parvus OBBP. These are methanotrophs that do not express sMMO, but express particulate MMO (pMMO) only, to utilise methane as a sole carbon and energy source. Functional expression of the sMMO operon of Ms. trichosporium OB3b was achieved in Mm. album BG8, however, recombinant sMMO enzyme activity was poor and problems were encountered with the growth of the sMMO positive transconjugant methanotrophs. (2) sMMO-minus marker exchange mutants of Ms. trichosporium OB3b (H. Martin and 1. C. Murrell (1995). FEMS Microbiol. Letts. 127, 243-248) were complemented with plasmid encoded genes and functional sMMO expression was obtained. Southern hybridisation analysis revealed that the plasmid DNA had integrated into the chromosome of the Ms. trichosporium OB3b sMMO-minus mutant via a single homologous recombination event between the mmoX genes. Protein B from Mc. capsulatus (Bath) is inactivated by proteolysis to give rise to a truncated form designated protein B'. The Met 12-Gly 13 cleavage site was modified by site-directed mutagenesis to Met12-Gln13 which improved the stability of the protein when incubated at room temperature. Only after prolonged incubation was protein B' formed. Recombinant protein B from Ms. trichosporium OB3b also appears to be unstable, and readily degraded when incubated at room temperature. The cleavage of protein B to inactive protein B' may be a general regulatory mechanism that occurs within the cell to regulate sMMO activity.