A low-power multichannel integrated circuit for reading out the signals of silicon detectors

An integrated circuit for reading signals from silicon detectors intended for systems for measuring charges of cosmic particles and nuclei in space-based experiments is described. It contains a 16-channel charge-sensitive amplifier and two additional operational amplifiers produced by the 0.35 μm CMOS process. The power consumption of the charge-sensitive amplifier is ≤1 mW/channel, and the rms deviation of the noise does not exceed 2000 electrons. Circuit designs for separate stages of the integrated circuit and experimental characteristics are given.     

Prognostic significance of ploidy level in human tumors. I. Carcinoma of the uterus

The 5-year survival rates of 540 patients with carcinoma of the cervix and 186 with carcinoma of the corpus uteri were assessed in relation to the modal DNA values of the tumors. Patients with squamous cell cervical carcinomas had more favorable prognoses if the modes were near-triploid or hypotetraploid; however, these high-ploidy tumors included more stage III cases than did the tumors with near-diploid modes. Patients with near-diploid endometrial carcinomas has considerably more favorable prognosis than did patients with the minority of tumors at this site, who had high modes; this prognostic difference was only partly related to a higher proportion of poorly differentiated tumors in the high-ploidy group since, among the poorly differentiated tumors, individuals with near-diploid modes again had significantly better prognoses than those with high modes.     

Negotiating the role of the practice nurse in general practice

The debate about the role of the practice nurse is not only about practice nursing per se, but raises broader issues about the organization of primary health care. Two related issues emerge as significant: the role of the practice nurse in providing primary health care; and the effective use of the practice nurse resource in the 'new' National Health Service. This paper, by drawing on material from a qualitative study, specifically examines the type of work performed by practice nurses and the factors that influence this. The responses of practice nurses, general practitioners, Family Health Service Authority (FHSA) advisers, community nurse purchasers and managers of community nursing provider units suggest that a consensus on the future development of practice nursing is unlikely. The different stakeholders emphasized different issues, reflecting their own priorities and backgrounds. Practice nurses' accounts of the future, for example, focused on professional issues. General practitioners stressed the importance of role development which met their General Medical Service responsibilities. Purchasing agencies, provider units and FHSAs adopted a wider perspective and were more concerned to develop an effective and integrated primary health care service. The tensions generated by their different interests and perspectives, and the subsequent organizational and policy initiatives that emerge, will provide the context in which the role of practice nurses will be negotiated.     

Phylogenetic and serological characterization of two Ugandan HIV-1 isolates

HIV-1 isolates Ug06 and Ug23 were established in culture from peripheral blood mononuclear cells (PBMCs) of Ugandan subjects. The isolates were studied for phylogenetic and serological relationships with each other and with the laboratory strains, HTLV-IIIB and HIV-1MN. The results suggest that the Ugandan isolates are related to different subgroups of African viruses with 17.3% of genetic distance between UG06 and the U455 provirus (Uganda); and 12.6% of genetic distance between UG23 and the JY1 provirus (Zaire). Analysis of the predicted amino acid sequences for Ug06 and Ug23 showed marked sequence heterogeneity in the V3 region and CD4-binding site. A conserved amino acid sequence was identified in the C-terminal immunodominant region of the envelope glycoprotein gp120. The isolates were compared in virus-neutralization experiments with HTLV-IIIB and HIV-1MN stocks, using panels of Western blot-positive North American and Ugandan sera. The North American serum samples showed broad neutralizing activity against both of the Ugandan isolates. However, the Ugandan serum panel demonstrated strain-specific activity against either Ug06 or Ug23. Furthermore, the African serum specimens showed higher prevalence and titers of neutralizing activity against the HIV-1MN stock as compared with HTLV-IIIB.     

Performance of optimum wavelet waveform for DS‐CDMA chip waveform over QS‐AWGN channel

In this paper, we search for a better chip waveform based on orthogonal wavelets for direct sequence‐code division multiple access (DS‐CDMA) signals to improve the probability of error (P_e) performance with minimal signal bandwidth variations. First, we derive the P_e expression over a quasi‐synchronous additive white Gaussian noise channel for DS‐CDMA signals, which use various pulse shaping waveforms including orthogonal wavelets as chip waveforms. It is observed that this expression depends on the chip waveform. Then, we design an optimum wavelet by using the relationship between wavelets and filter coefficients to reduce the probability of error. The DS‐CDMA system using the optimum wavelet waveform results in a lower probability of error than those using the conventional chip waveforms such as raised cosine, half‐sine and rectangular waveforms. Especially, the P_e of the optimum wavelet‐based scheme becomes significantly better than those of the conventional chip waveforms‐based schemes under the heavy loading that is the case for commercial wireless systems. When the systems work with full load (i.e. the number of users equals the processing gain), the optimum wavelet‐based system results in 0.5, 2.1 and 4 dB better SNR values than those of the raised cosine, half‐sine and rectangular‐based systems, respectively, for a P_e value of 10^?3. Copyright © 2005 John Wiley & Sons, Ltd.     

A comparison of two methods for reducing take-off delay at London Heathrow airport

This paper describes recent research into the departure process at London Heathrow, with the primary motivation of reducing the amount of fuel used, improving both the economic and environmental costs. Two proposals are considered here. The first proposal considers the practicality and potential benefits of aiding the controller in improving the take-off sequencing. The second proposal aims to absorb some of the inevitable delay for aircraft at the stands, before the engines are started, but also involves a take-off sequencing aspect. Models for the two take-off sequencing problems are presented in this paper, the second of which includes an additional pushback time (or TSAT) allocation sub-problem which has to be solved subsequently. These models have distinctive differences from the models for the take-off and arrival sequencing problems which are usually considered in the literature, since they take into account necessary constraints imposed due to the control problem (whether a sequence can actually be achieved, and how) in each case. As discussed in this paper, the control problem cannot be ignored by the controllers at Heathrow, and so it cannot be ignored by any realistic system to aid them in their tasks. Comparative take-off sequencing results are presented for the two systems, and the potential benefits from providing decision support to the runway controllers or improved TSAT allocation at the stands are considered. The paper ends with some overall conclusions from the research, showing the large potential benefits of these systems. The TSAT allocation system which is discussed in this paper has been developed for implementation at London Heathrow as one element of a major project which focuses upon collaborative decision making.     

Using the parallel process model to prevent firearm injury and death: field experiment results of a video-based intervention

This paper reports the outcome evaluation of a gun safety video intervention. Guided largely by the extended parallel process model, the video, Bullet 'Proof' - The Case for Gun Safety' focuses primarily on (a) knowledge of 6 gun safety practices, (b) susceptibility to accidental gunshot injuries and death, severity of gunshot injuries, (d) response efficacy, and (e) self-efficacy. The video was shown to 175 individuals in 7 hunter safety classes and evaluated in a field experiment using a posttest-only control-group design with random assignment. Compared to the control group, the experimental group listed significantly more gun safety practices, perceived greater susceptibility to accidental gun injuries, perceived gun injuries to be more severe, and perceived greater response efficacy toward some of the recommended gun safety practices. Further, all of the recommended gun safety practices received high self-efficacy and behavioral intention ratings. Finally, the video itself scored high on all measured positive attributes, and low on all measured negative attributes.     

Cytogenetics of Hodgkin's disease

Cytogenetic studies over the past 35 years have made a major contribution towards the understanding of the nature of Hodgkin's disease by demonstrating unequivocally the consistent presence of a clonal population of cells that have the cardinal features of malignancy e.g. more or less gross aneuploidy, frequently with complex chromosomal changes and showing considerable variation from case to case, thus comparable to the findings in carcinomas and other solid cancers. The mode is frequently in the triploid-tetraploid region, as we found in 17 of 27 cases studied in this laboratory by Feulgen microspectrophotometry, compared to only 10 cases with neardiploid modes. It is disappointing that no specific change, such as a translocation that could give a clue to the chromosomal location of a gene or genes involved in the etiology of Hodgkin's disease, has yet been found. Nevertheless it is clear that a number of nonrandom changes, including several that are also common in other malignancies including the non-Hodgkin's lymphomas, are frequently present, e.g., deletions of 1p, 6q, and 7q. Interestingly, deletions of 4q, with loss of 4q25 --> q27, that have also been reported may show some specificity for Hodgkin's disease.