Laparoscopic versus open colorectal resection for cancer and polyps: A cost-effectiveness study

Methods: Participants were recruited in 2006-2007 in a district general hospital in the south of England; those with a diagnosis of cancer or polyps were included in the analysis. Quality of life data were collected using EQ-5D, on alternate days after surgery for 4 weeks. Costs per patient, from a National Health Service perspective (in British pounds, 2006) comprised the sum of operative, hospital, and community costs. Missing data were filled using multiple imputation methods. The difference in mean quality adjusted life years and costs between surgery groups were estimated simultaneously using a multivariate regression model applied to 20 imputed datasets. The probability that laparoscopic surgery is cost-effective compared to open surgery for a given societal willingness-to-pay threshold is illustrated using a cost-effectiveness acceptability curve

Streamlined life cycle assessment of transparent silica aerogel made by supercritical drying

This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2011 ElsevierWhen developing sustainable building fabric technologies, it is essential that the energy use and CO2 burden arising from manufacture does not outweigh the respective in-use savings. This study investigates this paradigm by carrying out a streamlined life cycle assessment (LCA) of silica aerogel. This unique, nanoporous translucent insulation material has the lowest thermal conductivity of any solid, retaining up to four times as much heat as conventional insulation, whilst being highly transparent to light and solar radiation. Monolithic silica aerogel has been cited as the ‘holy grail’ of future glazing technology. Alternatively, translucent granular aerogel is now being produced on a commercial scale. In each case, many solvents are used in production, often accompanied by intensive drying processes, which may consume large amounts of energy and CO2. To date, there has been no peer-reviewed LCA of this material conducted to the ISO 14000 standard. Primary data for this ‘cradle-to-factory gate’ LCA is collected for silica aerogel made by low and high temperature supercritical drying. In both cases, the mass of raw materials and electricity usage for each process is monitored to determine the total energy use and CO2 burden. Findings are compared against the predicted operational savings arising from retrofitting translucent silica aerogel to a single glazed window to upgrade its thermal performance. Results should be treated as a conservative estimate as the aerogel is produced in a laboratory, which has not been developed for mass manufacture or refined to reduce its environmental impact. Furthermore, the samples are small and assumptions to upscale the manufacturing volume occur without major changes to production steps or equipment used. Despite this, parity between the CO2 burden and CO2 savings is achieved in less than 2 years, indicating that silica aerogel can provide a measurable environmental benefit.This work is funded by the EPSRC, Brunel University and Buro Happold Ltd, the University of Bath is funded by the EPSRC grant EP/F018622/1

Butyltin compounds in a sediment core from the old Tilbury basin, London, UK

Sections from a sediment core taken from the River Thames were analysed for butyltin species using gas chromatography with species-specific isotope dilution mass spectrometry. Results demonstrated that in most samples tributyltin concentrations of 20–60 ng/g accounted for <10% of the total butyltin species present, which is in agreement with data from other sediment samples which were historically contaminated with tributyltin. Vertical distribution of the organotin residues with depth throughout the core, with data on organochlorine compounds and heavy metals allowed for the construction of a consistent hypothesis on historical deposition of contaminated sediments. From this it was possible to infer that the concentrations of tributyltin in sediments deposited during the early 1960s were in the order of 400–600 lg/g by using degradation rate constants derived by other workers. Such values fall well within the range quoted for harbour sediments in the literature

Friction Laws for Elastic Nano-Scale Contacts

The effect of surface curvature on the law relating frictional forces F with normal load L is investigated by molecular dynamics simulations as a function of surface symmetry, adhesion, and contamination. Curved, non-adhering, dry, commensurate surfaces show a linear dependency, F proportional to L, similar to dry flat commensurate or amorphous surfaces and macroscopic surfaces. In contrast, curved, non-adhering, dry, amorphous surfaces show F proportional to L^(2/3) similar to friction force microscopes. In our model, adhesive effects are most adequately described by the Hertz plus offset model, as the simulations are confined to small contact radii. Curved lubricated or contaminated surfaces show again different behavior; details depend on how much of the contaminant gets squeezed out of the contact. Also, it is seen that the friction force in the lubricated case is mainly due to atoms at the entrance of the tip.Comment: 7 pages, 5 figures, submitted to Europhys. Let

AMR policy dialogue : driving innovative solutions for antimicrobial discovery

Antimicrobial resistance (AMR) is a global strategic priority and sits within the UK Government’s National Risk Register. By 2050, AMR is predicted to cause 10 million deaths, more than cancer. In 2019 alone, there were an estimated 4.95 million deaths associated with bacterial AMR. Although global pharmaceutical research and development (R&D) spend continues to increase year on year, research into antimicrobial drug discovery is not currently an attractive commercial investment. This has had two major consequences: an ongoing decline of human capital for R&D in this field, and a decline over the longer term in availability of therapeutically effective antibiotics and other antimicrobial agents. Concerted and coordinated efforts are needed to translate high-level policy commitments into strategic actions for long-term funding and support for the R&D of new antimicrobials

Headache Diagnosis in Primary Care

Introduction: Doctors in primary care are responsible for diagnosing and managing patients with headache, but frequently lack confidence in doing so. We aimed to compare Family Practitioners’ (FPs) diagnosis of headaches to classification based on a symptom questionnaire, and to describe how classification links to other important clinical features. Methods: This was an observational study of patients attending primary care doctors for headache. Main outcome measures: Patients completed a questionnaire including the Headache Impact Test, the Migraine Disability Assessment Score, the Hospital Anxiety and Depression Scale, the Illness Perceptions Questionnaire, a satisfaction scale, a service use inventory and a symptom questionnaire rated by two Practitioners with Special Interest (PSIs) in Headache. Results: 255 patients completed questionnaires. There was low agreement between FP diagnosis and classification using the symptom questionnaire. FPs frequently did not use the diagnosis migraine, when patient reported symptoms which justified this. FPs did not classify patients with ≥15 days of headache separately as chronic daily headache (CDH), and this could be because the classification system used does not have that code. Patients classified as CDH using the symptom questionnaire reported more disability, more symptoms of anxiety and depression (HADS), more service use, and less satisfaction with FP care. Conclusion: Patients, who present with headache in primary care, tend to receive non-specific diagnoses. Having a system that would allow separate classification of people with headache of ≥ 15 days a month might help FPs to explore and address associated features with patients in terms of disability, psychological co-morbidity and cost, and improve satisfaction with care

The behaviour of lubricated EHD contacts subjected to vibrations

Machine components containing contacts working in elastohydrodynamic (EHD) conditions are often subjected to vibrations. These may be originated from the mechanism or machine the contact is part of, the surrounding environment and within the contact itself. The influence of vibrations upon the behaviour of elastohydrodynamic films has been studied experimentally in a number of papers, but a comprehensive study of the effect of the parameters of the oscillatory motion upon the film thickness has not been carried out yet. In this study the authors evaluate the effect of the frequency of the oscillatory motion upon the EHD film thickness. Optical interferometry is used to measure lubricant film thickness in a ball-on-flat disc arrangement. A high – speed camera records the interferometric images for later analysis and conversion into film thickness maps. The disc runs at a constant angular velocity while the ball is driven by the traction forces developed in the EHD film. In steady state conditions, this would ensure pure rolling conditions, however in the present investigation the ball is subjected to harmonic vibrations in a direction perpendicular to the plane of the film. The contact under study is lubricated by basic oils and the temperature is kept at a constant value of 60°C. The aim of this paper is to understand how vibrations influence the lubricant film formation

Rolling friction of a viscous sphere on a hard plane

A first-principle continuum-mechanics expression for the rolling friction coefficient is obtained for the rolling motion of a viscoelastic sphere on a hard plane. It relates the friction coefficient to the viscous and elastic constants of the sphere material. The relation obtained refers to the case when the deformation of the sphere $\xi$ is small, the velocity of the sphere $V$ is much less than the speed of sound in the material and when the characteristic time $\xi/V$ is much larger than the dissipative relaxation times of the viscoelastic material. To our knowledge this is the first ``first-principle'' expression of the rolling friction coefficient which does not contain empirical parameters.Comment: 6 pages, 2 figure

Development of an automated measure of iliac artery tortuosity that successfully predicts early graft-related complications associated with endovascular aneurysm repair

Abstract not availableN. Dowson, M. Boult, P. Cowled, T. De Loryn, R. Fitridg

Rapid evolution of virulence and drug resistance in the emerging zoonotic pathogen Streptococcus suis

Background: Streptococcus suis is a zoonotic pathogen that infects pigs and can occasionally cause serious infections in humans. S. suis infections occur sporadically in human Europe and North America, but a recent major outbreak has been described in China with high levels of mortality. The mechanisms of S. suis pathogenesis in humans and pigs are poorly understood. Methodology/Principal Findings: The sequencing of whole genomes of S. suis isolates provides opportunities to investigate the genetic basis of infection. Here we describe whole genome sequences of three S. suis strains from the same lineage: one from European pigs, and two from human cases from China and Vietnam. Comparative genomic analysis was used to investigate the variability of these strains. S. suis is phylogenetically distinct from other Streptococcus species for which genome sequences are currently available. Accordingly, ,40% of the ,2 Mb genome is unique in comparison to other Streptococcus species. Finer genomic comparisons within the species showed a high level of sequence conservation; virtually all of the genome is common to the S. suis strains. The only exceptions are three ,90 kb regions, present in the two isolates from humans, composed of integrative conjugative elements and transposons. Carried in these regions are coding sequences associated with drug resistance. In addition, small-scale sequence variation has generated pseudogenes in putative virulence and colonization factors. Conclusions/Significance: The genomic inventories of genetically related S. suis strains, isolated from distinct hosts and diseases, exhibit high levels of conservation. However, the genomes provide evidence that horizontal gene transfer has contributed to the evolution of drug resistance