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Notes: AbstractThe paper reviews the work done and conclusions reached on resource allocation to R&D in the public sector in the last twenty years, and examines what changes have been made in the field of R&D assessment. The paper is based mainly on the author's experience with the UK government's Programmes Analysis Unit (PAU) which was set up in the early 1960s.The Unit's main remit was to examine and disseminate techniques by the use of which the benefit to the nation from possible R&D strategies, programmes and projects might be calculated. It was also called in to help review policy and carry out long-range forecasting. In the course of its existence — it was wound up in 1977 — it analysed many new techniques of analysis which have now passed into common use and took part in studies to support decisions at all levels from the macro-economic sector down to the individual project.The author lists the benefits derivable from such analyses — helping to identify objectives, assemble total programmes, evaluate efficiency of technological transfer, carry out technology assessment and so on. But he warns of their limitations.As for the present day, the author is unhappy about the importance given by the UK Government to the market as a test of value in decision-making about R&D, in so far as it leads to neglect of long-term issues and relies on uncertain causal relationships among critical inputs. Cost-benefit is adequate for dealing with short-term, small-scale projects. For larger projects with controversial long-term implications he advocates broader-based techniques such as multi-attribute analysis, which bring the interests of many parties into the judgment and take into account considerations such as the environment, finite resources and social

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: 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: IRAS (infrared reflection absorption spectroscopy) has been employed to study the isotopic mixing reaction: 13C16O(a)+12C18O(a)→13C18O(a)+12C16O(a) on Ni(111) with preadsorbed K adatoms. Under high temperature conditions (T〉450 K) where the isotopically mixed CO is being desorbed, it has been shown that the isotopic exchange reaction cannot be detected by IRAS on the surface among CO molecules strongly interacting with K adatoms. This result implies that dissociation of CO occurs at K-promoted Ni sites followed by surface diffusion of C(a) and O(a) away from the K promoter site. Statistical recombination of C(a)+O(a) occurs with concomitant CO desorption on Ni(111) sites some distance from K centers. The empty K-promoted sites may be refilled by surface diffusion of CO from outside. Thus, alkali metal promotion of C–O bond scission may act via a "feeder-site'' mechanism connecting promoter atoms to external surface sites via surface diffusion of atomic C and O species.

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: 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 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: 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.