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Introduction Biliary papillomatosis (BP) is a rare condition with a strong potential for malignant transformation and cases from Western centres are sparse. 1 We discuss the presentation, investigation and management of this condition in three Caucasian patients and present a review of the existing literature on BP. Patients and methods The case notes of three Caucasian patients with BP who presented to our tertiary referral centre were reviewed. Their case histories, investigations and managements are presented. A search of MEDLINE, PubMed and Cochrane databases was performed to review relevant literature around BP. Discussion BP is a rare condition characterised by multiple papillary adenomas involving the biliary tree which lead to recurrent attacks of cholangitis. It is a low-grade neoplasm with high malignant potential and should be regarded as a pre-malignant lesion.

Two-phase flow of water and reactant gases in the gas distribution channels of proton exchange membrane fuel cells (PEMFCs) plays a critical role in proper water management. In this work, the two-phase flow in PEMFC cathode parallel channels is studied over a wide range of superficial air velocity (air stoichiometry) and superficial water velocity in a specially designed ex situ experimental setup, which enables the measurement of instantaneous flow rates in individual gas channels and simultaneous visualization of the water flow structure. It is found that the two-phase flow at low superficial air velocities (air stoichiometry below 5) is dominated by slugs or semi-slugs, leading to severe flow maldistribution and large fluctuations in the pressure drop. Slug residence time, measured from the video observation and the instantaneous flow rate data, is found to be a new parameter to describe the slug flow. At higher air velocities, a water film is formed on the channel walls if they are hydrophilic. The pressure drop for the film flow is characterized by smaller but frequent fluctuations, which are found to result from the water buildup at the channel-exit manifold interface. As the superficial air velocity increases further, mist flow is obtained where little water buildup is observed. The water buildup in the gas channels at the two-phase flow is well described by the two-phase friction multiplier, defined as the ratio of the two-phase pressure drop to the single gas phase pressure drop. It is found that the two-phase friction multiplier increases with increasing water flow rate. A flow pattern map is developed using superficial water and air velocities with clearly defined transition regions.

Introduction Sinusoidal obstructive syndrome (SOS) is well associated with the use oxaliplatin-based chemotherapy, and represents a spectrum of hepatotoxicity, with nodular regenerative hyperplasia (NRH) representing the most significant degree of injury. The aim of this study was to determine the prevalence of NRH in patients undergoing resection of colorectal liver metastases (CRLM) and to determine its impact on outcome. Methods From January 2000 to December 2010, some 978 first primary liver resections were performed for CRLM. A prospectively maintained database was analysed to identify all patients with evidence of NRH in the non-tumour portion of their histopathology specimens. Clinical data of these patients was reviewed and outcomes assessed. Results Five patients exhibited NRH (four males, one female) with a median age of 69 years (range: 35–74). Three patients presented with synchronous hepatic metastases, and two with metachronous lesions. All received at least 6 cycles of oxaliplatin as either adjuvant or neo-adjuvant chemotherapy. Only one patient developed a post-operative complication namely transient hepatic failure that required a 4-day stay in the intensive care unit. The median hospital stay was 6 days (range: 6–14 days). There were no 90-day mortalities. One patient is alive and disease free at 55 months, the remaining 4 died of recurrent disease between 37 and 70 months following diagnosis of their primary tumours. Conclusions NRH is not an uncommon finding amongst patients with SOS with all patients having received oxaliplatin-based chemotherapy. Data on outcome would suggest no increased morbidity and mortality associated with the presence of NRH.

A hemispherical lens-reflector uses of a ground plane to recovers the full aperture of a spherical lens. This is advantageous for applications requiring a low-profile antenna such as on trains. We have developed a 61 cm diameter lens with a mechanical beam steering system using two independently steered primary feeds for Ku and Ka bands. The intended application is satellite communications to enable media and internet services for passengers. We report the design rationale along with measured radiation patterns at 10-12 GHz, 20 GHz and 30 GHz. (7 pages)

The Swiss-based "StratXX" project during 2006-2007 has been developing a stratospheric lighter-than-air platform for deployment of telecommunications and environmental monitoring services. In support of a first round of experimental trials, a WiMAX communications subsystem, including platform payload and ground stations, has been developed. The communications system design and results of terrestrial pretrials are reported.

This work utilizes the channel design of a real fuel cell to study cathode side water transport in the gas channels of a proton exchange membrane fuel cell (PEMFC). All experimentation was performed under controlled water and air flow conditions aimed to meet the DOE targets [1] for the automotive fuel cells. The experimental facility provides independent control for water flow along the length of the channels to reduce the effects of channel pressure drop on the water flow. Details of channel design and instrumentation are described, as well as some initial results.Copyright © 2008 by ASME

The use of computer-based real-time visual displays is now well established in voice clinics. A number of situations exist, however, where a computer-based system is inconvenient and a battery-powered hand-held version would be preferred. This would, for example, enable voice monitoring to be carried out at any time and place, including during home visits. This paper describes a purpose-built device that provides real-time displays of fundamental frequency and larynx closed quotient (CQ) derived from the electrolaryngograph output. The fundamental frequency data can in addition, be acquired from a microphone. The system has been in use recently in a speech and language therapy clinic in Sheffield, UK and the advantages and disadvantages noted during that trial are discussed.

The use of real time visual displays by speech and language therapists for the representation of voice source characteristics such as fundamental frequency (F0) and electrolaryngographically (Lx) derived vocal fold closed quotient (CQ) is now well established. This trend has been made possible by the widespread availability of fast computers and dedicated signal processing devices. However, many users of such equipment have expressed a need for a portable, battery operated device displaying F0 and CQ, not only for specific use by the therapist but also for the use by clients outside the usual clinical consultation where appropriate. At the University of York, we have developed a portable hand-held system based on the electrolaryngograph output waveform and a high performance microcontroller chip. The system can display graphically against time measures of f/sub 0/, larynx CQ and a normalised display of individual Lx cycles. The paper describes the development, implementation and basic operation of the voice analyser system.

The frequency of non-clonal structural and numerical chromosome aberrations in peripheral blood lymphocytes of 51 patients with MDS and 37 age-matched hematologically normal subjects is assessed. The frequency of aneuploid cells (p less than 0.001) and of structural aberrations (p less than 0.005) was significantly higher in MDS patients than in normal subjects, but showed no relationship with FAB type or with the presence of clonal karyotype abnormalities in the bone marrow. Exchange configurations were only observed in MDS patients (27.5%). The data also suggest that there may be an association between high peripheral blood aberration levels and rapidly progressive disease. This may indicate increased mutagen sensitivity and have implications for treatment.

Cytogenetic data on two cases of previously treated Waldenstrom's macroglobulinemia (WM) are presented. An i(6p) was identified in 60 and 56% of bone marrow (BM) metaphases from each patient, respectively. In both cases, i(6p) occurred as part of a complex karyotype but was also observed as the sole abnormality in a proportion of metaphases. The literature on the cytogenetics of WM and the relevance of i(6p) is discussed.

Summary We report the occurrence of two side effects, pancreatitis and palindromic arthropathy with effusions, associated with injections of sodium stibogluconate used in the treatment of kala-azar. No clear mechanism to account for the problems was identified despite extensive investigation. We suggest that when abdominal pain is experienced during treatment with antimonial drugs pancreatitis should be borne in mind as a possible cause.

Multiple sclerosis (MS) may occur outside the commonly accepted age range. Data relating to features of MS in a population in South Wales have been analysed to find features which characterise older patients. The older patients are more severely disabled due to the accumulation of visual defects and motor signs and symptoms. The course of the disease is marked by single localised attacks with long remissions. Those with onset over 50 years deteriorate more rapidly, but in those who were over 50 at the time of interview, this did not occur. It is suggested that there is no essential difference in MS in older patients, but there may be features which reflect normal ageing and diseases commoner in old age.

The control of vibration through the mounts of rotating machines can be achieved by actively generating cancelling forces from shakers located close to the mounts. The cancelling waveforms cannot simply be an antiphase copy of the original waveform as each shaker affects the vibration at mounts other than the one at which it is cancelling. This paper describes an approach to this multivariable control problem which measures all shaker to sensor transfer functions to give a shaker transfer function matrix, M (f) . The shakers are driven by voltages V (f) given by V (f) = −M −1 (f) U (f) where U (f) is the vector of accelerations at the mounts. The controller then repeats the algorithm, this time operating on the residual accelerations at the sensors. The system is therefore adaptive and can cope with slowly changing noise spectra. Cancellations of better than −25 dB have been achieved.

A technique using human lymphocytes together with an Ames-type microsomal (S9) activation system for testig indirect chemical mutagens has been developed and examined. The cytotoxic drug cyclophosphamide (CP), which only displays mutagenic properties after metabolic activation, was used as a test chemical and mutagenicity assessed in terms of sister-chromatid exchange (SCE) induction. Direct exposure of lymphocytes to CP and S9 mix produced increases in the yield of SCE for CP concentrations down to 10 −6 M. Exposure times of 30, 60 and 120 min commencing at the beginning of cell culture or after 48 h gave different ranges of detection and response with later treatment being more effective for SCE induction. Variations in relative proportions of the S9 mix culture medium constituents affected the lymphocytes' tolerance of toxic factors and modifiec the mutagen's effect. CP pre-incubated with S9 mix for 1 h before adding to the lymphocyte cultures also produced increases in SCE levels but the method was complicated and did not reduce toxicity. Direct addition of CP and S9 mix to the lymphocytes without prior pre-incubation showed maximum sensitivity, minimum toxocity and was a simpler, more reliable technique.

Low cost pollution sensors have been widely publicized, in principle offering increased information on the distribution of air pollution and a democratization of air quality measurements to amateur users. We report a laboratory study of commonly-used electrochemical sensors and quantify a number of cross-interferences with other atmospheric chemicals, some of which become significant at typical suburban air pollution concentrations. We highlight that artefact signals from co-sampled pollutants such as CO2 can be greater than the electrochemical sensor signal generated by the measurand. We subsequently tested in ambient air, over a period of three weeks, twenty identical commercial sensor packages alongside standard measurements and report on the degree of agreement between references and sensors. We then explore potential experimental approaches to improve sensor performance, enhancing outputs from qualitative to quantitative, focusing on low cost VOC photoionization sensors. Careful signal handling, for example, was seen to improve limits of detection by one order of magnitude. The quantity, magnitude and complexity of analytical interferences that must be characterised to convert a signal into a quantitative observation, with known uncertainties, make standard individual parameter regression inappropriate. We show that one potential solution to this problem is the application of supervised machine learning approaches such as boosted regression trees and Gaussian processes emulation.

Human lymphocytes cultured for 73 h in the presence of BrdU were exposed to epichlorohydrin (ECH) with and without metabolic activation. Cells exposed for the entire culture time without activation showed a significant dose-related increase in SCE yield. Exposure for the final 25 h only showed a similar response but with increased tolerance. The presence of S9 mix significantly reduced the effect of ECH compared with a similar exposure without activation. Without activation 4 × 10 −4 M ECH produced a 3-fold increase in the incidence of SCE over the control level. However, with S9 mix a concentration of 10 −3 M ECH was required to produce such an increase indicating that S9 mix may have a detoxifying effect.

A simple adaptive Kalman filter has been developed to give optimal estimation of a ship's course, speed and position giving sufficient accuracy to be useful for the processing of marine gravity measurements. The inputs to the filter are from the ship's electromagnetic log, gyrocompass and radio navaid. The radio-navaid noise is assumed to be zero mean and white, but it is shown that the filter still works satisfactorily when the noise is coloured, with a spectrum similar to that obtained from long-range marine radio navaids beyond the edges of their present useful operating areas. The log and gyrocompass noises are assumed to be white and nonzero mean, and the effects of these nonzero means (due to wind and current in practice) examined. An algorithm is developed to offset the effects of the nonzero means. The sensitivity of the filter to incorrect data statistics is examined and a limited-memory radio-navaid variance estimator incorporated. Finally, the developed filter is used with real ship data obtained from the ocean survey ship, HMS Hecla.