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Notes: In the COMPASS-D tokamak three multiviewing diagnostic systems are combined by using the same collection optics. HeI line ratios from a helium thermal jet provide detailed edge Te(r) and ne(r) profiles. The spectrometer also provides the Dα profile. A Doppler spectrometer system provides Ti and Vθ profiles using HeII emission. The Te and ne profiles are used in extracting neutral densities from the Dα emissivities, and the radial electric field from the Doppler measurements. The behavior of Te(r), ne(r), 2nD(r), Er, and Vθ and their gradients can now be compared in detail to investigate the H-mode transition physics. © 2001 American Institute of Physics.

Notes: A micrographic investigation of the effect of mercury exposure on silicon substrates was conducted. Mercury was found to leave a residue on the silicon surface. A further study was conducted to determine the extent of electrical degradation of Si Schottky contacts due to the presence of a contaminant mercury residue between the metal and the semiconductor. It was concluded that such a layer caused uncertainties in subsequent resistivity measurements, higher capacitance-voltage (C-V) barrier heights, and observable leakage currents in current-voltage (I-V) plots taken from mercury-contaminated Si Schottky diodes.

Notes: The etching of silicon in CF3Br/O2 plasmas has been examined. In situ x-ray photoelectron spectroscopy shows that silicon surfaces etched in CF3Br/O2 plasmas with a proportion of 30% O2 or less are covered with a reaction layer that is mainly due to bromine bonded to silicon. As the proportion of oxygen is increased above 30% the reaction layer becomes thicker and contains mainly fluorine and oxygen, and the silicon etch rate decreases simultaneously.

Notes: A Dy-substituted Fe14Nd2B-type permanent magnet alloy (Crumax 32) has been studied by positron annihilation lifetime spectroscopy, and also magnetic coercivity and microstructural analysis, to evaluate the effects of thermal treatment of the material. The results of this study show that the room temperature lifetime spectra can be modeled accurately using a partially constrained three-component fit. The variations in lifetime spectra induced by thermal treatment of the sintered magnet can be correlated with the concomitant decreases in coercivity and with a decrease in the surface area of free α-Fe as indicated by transmission electron microscopy.

Notes: This paper reviews the state of the field of the sub-disciplines within UK management research, based upon the submissions of 94 UK higher education institutions to the Business and Management Studies Panel in the UK's 2001 Research Assessment Exercise (RAE). It offers observations on the UK model of the assessment of quality in, and funding of, research conducted in publicly funded higher education institutions.

Notes: Objective To analyse biopsies of large loop excision of the transformation zone of the cervix; to identify factors associated with negative histology; and to develop predictive models in order to reduce the number of negative loop excisions.Design Retrospective analysis of patient notes and audit database.Setting Colposcopy clinic of a large district general hospital in North Staffordshire.Population Four hundred and fifty-two women who underwent a large loop excision of the transformation zone (LLETZ) procedure for suspected cervical intraepithelial neoplasia.Methods Women who underwent a LLETZ procedure were placed in two different groups, one positive for cervical intra epithelial neoplasia and the other negative for cervical intra epithelial neoplasia. Information was obtained on a number of clinical and colposcopic variables. Analysis was undertaken to determine if there were any differences between the two groups. These factors were then identified and three predictive models generated. Receiver-operator characteristic curves were used to assess and test these models.Main outcomes measures To identify factors associated with negative histology on a LLETZ specimen. To predict how to reduce the number of negative LLETZ specimens.Results Four hundred and fifty-two women underwent a LLETZ procedure, 88 were negative (19%) and 364 were positive (81%). In women who were treated at their first visit, 56/316 (18%) had negative histology. There were significant associations between negative histology in the LLETZ and negative or low grade cytological atypia, negative colposcopic findings and years of age 〉 50 in both bivariate analysis and stepwise logistic regression. In the predictive models, the sensitivity ranged between 72% and 80%, the specificity 59%–72%, and the area under the receiver-operator characteristic was 0.75–0.77. If we had used the predictor models and managed women with negative or low grade cervical atypia and negative colposcopy findings conservatively, we would have reduced the negative biopsy rate from 19% to 14%, but five cases of high grade disease and 25 cases of low grade disease would have been missed. If we had also included women aged 〉 50 years in this model, the negative biopsy rate would have dropped from 19% to 15%, with only one case of high grade disease and 11 cases of low grade disease missed. All these women would require continued cytological and colposcopic surveillance. Importantly, no cases of invasion would have been missed.Conclusion Using a predictive model can reduce the number of negative LLETZ specimens, but at the expense of continued cytological and colposcopic surveillance and cannot be recommended in normal practice. This raises the question whether current standards for negative histology in LLETZ specimens are set unrealistically high.

Notes: Objective To test the hypothesis that prilocaine with felypressin causes fewer side effects than lignocaine with adrenaline when performing large loop excision of the transformation zone of the cervix.Design Randomised trial.Setting Colposcopy clinic in a large district general hospital.Participants Two hundred consecutive women undergoing large loop excision of the transformation zone of the cervix.Methods Two different local anaesthetic combinations (prilocaine with felypressin and lignocaine with adrenaline) were compared in women undergoing large loop excision of the transformation zone. Prospective collection of clinical and treatment data was undertaken with scoring using an ordinal scale of pain experienced by the women during the procedure. Peri-operative blood loss and any side effects were also recorded.Main outcome measures Side effects associated with the local anaesthetic agents.Results Lignocaine with adrenaline resulted in less blood loss (P= 0.006) but was more likely to cause side effects, such as feeling faint (P= 0.017) and shaking (P 〈 0.001).Conclusion Prilocaine with felypressin causes fewer side effects than lignocaine with adrenaline and is therefore the preferred local anaesthetic combination for large loop excision of the transformation zone.

Notes: Seventy-one patients scheduled to undergo upper or lower abdominal surgical procedures were allocated at random to one of seven treatment groups: in the recovery room they were to receive oxygen via a 40% Ventimask with 10 litres/minute oxygen flow, or via either a Hudson mask or a nasal cannula with 3,6 or 9 litres/minute oxygen flow. The 40% Ventimask gave the most consistent, satisfactory postoperative values of PaO2 but the much cheaper nasal cannula at 6 or 9 litres/minute was generally adequate in conscious patients. The performance of the intermediately priced Hudson mask was similar to that of the nasal cannula at these flows. The unconscious state was associated with a 45% lower PaO2 than the rousable or awake states. Differences between the treatments with regard to postoperative PaCO2 were small and non-significant. The nasal cannula with 6 litres, minute humidified oxygen flow is recommended for routine treatment, and the Ventimask for unconscious patients.

Notes: The anaesthetic management of a 26-year-old woman who sustained an unstable fracture of C2 when 40 weeks pregnant, is described.