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Smoking contributes to health inequalities for people with severe mental illness (SMI). Although smoking cessation interventions are effective in the short term, there are few long-term trial-based estimates of abstinence. The SCIMITAR trials programme includes the largest trial to date of a smoking cessation intervention for people with SMI, but this was underpowered to detect anticipated long-term quit rates. By pooling pilot and full-trial data we found that quit rates were maintained at 12 months (OR = 1.67, 95% CI 1.02–2.73, P = 0.04). Policymakers can now be confident that bespoke smoking cessation interventions produce successful short- and long-term quitting.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
One proposed approach to reduce the spread of HIV is to prevent transmission of the virus through the use of a topical microbicide. One microbicide strategy is a charge inhibition based approach using polyanionic compounds designed to interfere with the process of HIV-1 attachment to potential target cells. This strategy however, is predicated on further understanding the charge characteristics of whole virions and the relative contribution of viral and host-cell proteins to such charge. Electrokinetic methods (i.e. ζ-potential) provide information on the surface structure of biological cells without producing significant alteration of the cellular organization. Electrophoretic fingerprinting (EF) is obtained from 3D templates of the mean electrophoretic mobility (the raw data from which ζ-potential is calculated) of a given particle versus pH and solution conductivity at a fixed temperature. The EF thus represents a surface, described by isomobility lines, over all pertinent electrochemical conditions. These initial electrophoretic analyses have been performed using human CD4+ T cell lines. The cell lines are derived from human white blood cells which are the principle targets of the HIV-1 virus. Tissue culture work was carried out under Class II aseptic conditions. Cell types were maintained in RPMI growth medium supplemented with 10% heat inactivated foetal calf serum, 2mM glutamine, 100 i.u./ml penicillin and 100 μg/ml streptomycin at 37°C in a humidified 5% CO2 incubator. The cells were routinely passaged every 3-4 days in 75 cm3 fillter cap tissue culture flasks, by the addition of 4 mls of cells to 16 mls of fresh growth medium.Electrophoretic mobility (ζ-potential) was measured as a function of pH and ionic strength over a range chosen to cover that known for fluids found in the lower female reproductive tract, including vaginal fluid and semen. Measurements were made using a Malvern ZetaSizer NanoZS operating in the fast field reversal mode (PALS). Data was analyzed using SURFER™ software and the results validated from the covariance matrix of the linear fit. Challenges in the measurement and characterization of the cells include the difficulty of the cell preparation, cleanliness of the samples and sample handling required to maintain cell vitality.Overall, the EF’s analyzed under environments characteristic of physiological conditions for each CD4 T cell line resulted in similar zwitterionic surface charge features. These results suggest that the best candidate for a microbicide active needs, itself, to be zwitterionic so as to be able to mirror-image the shift in sign of surface charge as the pH of the vaginal tract changes. Current results suggest that HIV interaction with target cells is enhanced by physiological fluids. The data provides core information on the physico-chemical properties of model cellular targets for HIV-1 infection and pave the way for rational development of charge-based intervention strategies.
Dental amalgam has been used as a filling material in dentistry for over 100 years. The reactants, Ag3Sn alloy and mercury, form silver-mercury and tin-mercury products. Previous X-ray diffraction studies have resulted in some disagreement concerning unit-cell structure and parameters of the products. In this study, X-ray diffraction measurements were carried out on tin-mercury mixtures, tin-mercury alloys, dental amalgam, and single crystals of tin and mercury. The diffraction data for the tin-mercury alloys were programed for an IBM 650 computer utilizing Cohen's least-squares method. The tin-mercury product was found to be a solid solution possessing hexagonal-symmetry elements. The parameters ranged from: c0 = 2.995 A to 2.984 A, co/ao = 0.931.
The easy availability of small aircraft for charter, has been accompanied by increasing willingness on the part of insurance companies to pay the costs for the use of these air ambulances. Operators of aircraft in the United Kingdom and Europe were becoming increasingly worried about the moral, medical and legal implications of carrying seriously ill or injured passengers. In late 1980 the UK Air Taxi Operators Association (ATOA) began to formulate Guidelines for air ambulance operations, and in 1981 these were incorporated into the studies of the same subject by the International Business Aircraft Association (IBAA), Europe. This paper presents the Guidelines adopted by the ATOA and ratified by IBAA Europe. The Guidelines are designed not to hamper the development of aeormedical rescue, but to bring it within a proper medical aeronautical framework for the safety of the patients, and medical and aircraft crews.
During the last 30 years development of the international travel market in Europe has resulted in many patients becoming ill or suffering injuries many miles from their own home. In the past these people would have remained in a local hospital and received treatment by the locally available facilities. There has been a revolution in the technology of medical transport, providing skills and equipment which allows the most seriously injured people to be transported over long distances. The public demand has pressed insurance companies to offer as part of travel packages the possiblity of medical repatriation. The number of new serious medical cases abroad reported to Europ Assistance in London, rose from 736 in 1978 to a projected 3,500 in 1983.
When droplets of dilute suspensions are left to evaporate the final dry residue is typically the familiar coffee-ring stain, with nearly all material deposited at the initial triple line (Deegan et al., Nature, vol. 389, 1997, pp. 827–829). However, aqueous poly(ethylene oxide) (PEO) droplets only form coffee-ring stains for a very narrow range of the experimental parameters molecular weight, concentration and drying rate. Instead, over a wide range of values they form either a flat disk or a very distinctive tall central monolith via a four-stage deposition process which includes a remarkable bootstrap-building step. To predict which deposit will form, we present a quantitative model comparing the effects of advective build-up at the triple line to diffusive flux and use this to calculate a dimensionless number . By experimentally varying concentration and flux (using a low-pressure drying chamber), the prediction is tested over nearly two orders of magnitude in both variables and shown to be in good agreement with the boundary between disks and monoliths at .
The DRINK code is a 2D, biogeochemical transport code developed as a research tool to simulate the long term evolution of near surface LLW disposal sites and to generate gaseous and liquid source terms for far field studies. The code was recently upgraded to provide a more generic modelling tool with wider application to radionuclide migration scenarios. During the development of this code, the Generalised Repository Model (GRM), an integrated strategy has been employed to ensure the production of a fully tested, verified and quality assured product. This strategy is based around a code development protocol with three main components: quality assurance and documentation, verification and realism testing. Realism testing includes both peer review and model testing, with the latter including: experimental test cases; natural and anthropogenic analogues; field observations and finally uncertainty and sensitivity analysis. This paper describes the successful application of the protocol to the development and testing of the GRM code with specific emphasis upon verification and realism testing.
‘In poetry’, Matthew Arnold announced in 1880, ‘the spirit of our race will find … its consolation and stay.’ It is a reassuring idea, but as Arnold had already pointed out in the Preface to his 1853 Poems, the hope that poetry would provide a cultural ‘stay’ (a device for supporting or steadying a structure) was all too often hampered in the period by writing which seemed to be suffering from a different form of ‘stay’: ‘a stoppage, arrest, or suspension of action; a check, set-back’. Consider W. H. Mallock’s pamphlet Every Man His Own Poet: Or, The Inspired Singer’s Recipe Book (1872), which offered tongue-in-cheek advice on ‘How To Write A Poem Like Mr Tennyson’. To produce an epic like Idylls of the King, for example, take ‘one blameless prig’, add ‘a beautiful wife’ and ‘one married goodly man’, tie them together in a bundle ‘with a link or two of Destiny’, and surround them by ‘a large number of men and women of the nineteenth century, in fairy-ball costume, flavoured with a great many possible vices, and a few impossible virtues’.
Stir these briskly about for two volumes, to the great annoyance of the blameless prig, who is, however, to be kept carefully below swearing-point, for the whole time. If he once boils over into any natural action or exclamation, he is forthwith worthless, and you must get another. Next break the wife’s reputation into small pieces, and dust them well over the blameless prig. Then take a few vials of tribulation, and wrath, and empty these generally over the whole ingredients of your poem, and, taking the sword of the heathen, cut into small pieces the greater part of your minor characters. Then wound slightly the head of the blameless prig, remove him suddenly from the table, and keep him in a cool barge for future use.
We consider the problem of state and parameter estimation for a class of nonlinear
oscillators defined as a system of coupled nonlinear ordinary differential equations.
Observable variables are limited to a few components of state vector and an input signal.
This class of systems describes a set of canonic models governing the dynamics of evoked
potential in neural membranes, including Hodgkin-Huxley, Hindmarsh-Rose, FitzHugh-Nagumo,
and Morris-Lecar models. We consider the problem of state and parameter reconstruction for
these models within the classical framework of observer design. This framework offers
computationally-efficient solutions to the problem of state and parameter reconstruction
of a system of nonlinear differential equations, provided that these equations are in the
so-called adaptive observer canonic form. We show that despite typical neural oscillators
being locally observable they are not in the adaptive canonic observer form. Furthermore,
we show that no parameter-independent diffeomorphism exists such that the original
equations of these models can be transformed into the adaptive canonic observer form. We
demonstrate, however, that for the class of Hindmarsh-Rose and FitzHugh-Nagumo models,
parameter-dependent coordinate transformations can be used to render these systems into
the adaptive observer canonical form. This allows reconstruction, at least partially and
up to a (bi)linear transformation, of unknown state and parameter values with exponential
rate of convergence. In order to avoid the problem of only partial reconstruction and at
the same time to be able to deal with more general nonlinear models in which the unknown
parameters enter the system nonlinearly, we present a new method for state and parameter
reconstruction for these systems. The method combines advantages of standard
Lyapunov-based design with more flexible design and analysis techniques based on the
notions of positive invariance and small-gain theorems. We show that this flexibility
allows to overcome ill-conditioning and non-uniqueness issues arising in this problem.
Effectiveness of our method is illustrated with simple numerical examples.
An increasing number of blood tests are being performed in primary care. Informing patients of results takes up a considerable proportion of practice-staff time. The use of new technologies may be more time-efficient for staff but little is known about the acceptability to patients.
To determine patient attitudes towards the use of three technologies – short message service (SMS), webpage and e-mail – for the delivery of laboratory results.
Two hundred patients were interviewed in two general practices in Lothian, Scotland. Satisfaction with current methods and preferred methods of obtaining test-results were assessed. Patients were asked about their current access to different technologies and their favourability to using such technologies for receiving results and their views on appropriate content and information security. Results were analyzed by age, sex and educational attainment using χ2 test.
A total of 79.5% of patients had mobile phones, 53% used SMS, 46.5% had internet, and 37.5% used e-mail. E-mail, SMS and webpage was the favoured delivery system for 53.3%, 37.1% and 33.3%, respectively.
Patients were favourable towards e-mail but not SMS or a webpage. The main concern over the three technologies was information security. New technology may be useful for delivering results but patients will have to be persuaded that any such system is reliable and secure.
“They used to say I was an odd child, and I suppose I was. I am an odd man, perhaps.” 'Gone Astray', Household Words, 13 August 1853 / Ever since John Forster published Dickens's autobiographical fragment in his Life of Charles Dickens, readers have known about the main events that marked Dickens's childhood and continued to trouble him as an adult: his father's arrest for bankruptcy and time in the Marshalsea prison; the period he spent working as a 'poor little drudge' in Warren's blacking warehouse; and his loneliness as he wandered the streets of London, slowly sinking into the dirt and misery of those other poor drudges living on the edges of recognition, never more than a few shillings away from his 'vagabond existence' hardening into a permanent way of life. “The deep remembrance of the sense I had of being utterly neglected and hopeless; of the shame I felt in my position; of the misery it was to my young heart to believe that, day by day, what I had learned, and thought, and delighted in, and raised my fancy and emulation up by, was passing from me, never to be brought back any more; cannot be written.” But it could be rewritten. Throughout his career, the figure of an innocent child lost in the city is one that Dickens returns to like someone touching a bruise, at once drawing him back and driving him on. In 'Gone Astray', for example, an essay first published in Household Words in 1853, he explains how, as 'a very small boy indeed, both in years and stature, I got lost one day in the City of London', and as the essay develops, what starts off as a sliver of autobiography quickly takes on the resonance of a founding myth.
botulinum toxin a (btx-a) is increasingly being used in early management of spasticity in ambulant children with cerebral palsy (cp), with the aim of improving function, promoting muscle growth, and delaying the need for surgical intervention. however, there is a lack of evidence about the long-term outcome of btx-a injections. the focus on spasticity as the predominant problem in younger children with spastic cp may not fully consider the associated muscle weakness. it also raises concern that although btx-a may improve function in the short term, it has the potential to affect muscle growth and function adversely in the long term. a cautious approach to the early use of btx-a, with the use of objective outcome measures within a specialized multidisciplinary setting, is recommended, particularly in ambulant children with spastic diplegic cp, until further evidence is available on the long-term outcome of early btx-a injections in children with cp.
The existence of glass or amorphous component in Portland cement clinker has been questioned for a long time. However, besides the crystalline phases, there are reports in the literature of noncrystalline material in cement clinker, which is considered to be the residue of the melt that has failed to crystallize. Absolute phase abundances were determined in this study by Rietveld refinements with laboratory X-ray data, using both internal and external phase composition standards. The results clearly demonstrate the existence of an amorphous component in Portland cement clinker. The presence of an amorphous component was also apparent from diffraction data for clinker from which the silicate phases had been chemically removed, using both laboratory X-ray and synchrotron radiation patterns.
Modem disc centrifuge technology has extended the range of application of sedimentation particle size analysis to include the submicron region. An overall size range of approximately 10 nm to 100 pm is now accessible. The principles of both the disc centrifuge photosedimentometer, which employs optical detection with full Mie light scattering corrections, and the X-ray disc centrifuge are described. Examples of their application to a variety of samples are given to illustrate the performance characteristics of the instruments including a direct comparison of resolving power with that of the laser diffraction technique.
In his book In the end, God… Dr J. A. T. Robinson argues for luniversalism from two myths of the end, one taken from Matthew 25.31–46 and the other from Paul (London: James Clarke, 1950, p. 99 f). If the two myths were both taken from the sayings of Jesus his argument would be immeasurably stronger, though it is fair to add that he does see them both being represented in the present in John 3.17–18 (p. ioo).2
The main purpose of this paper is to outline the position which the propeller holds in current aircraft propulsion, its construction, operation and its future. The paper has been arranged in four parts, as follows:–
1.Present and future types of aircraft foreseen with propellers.
2.Engines for turbo-prop power units.
In the present military field propellers are used for the following types of aircraft:—Heavy transport and Army reconnaissance, for example the Beverley and Pioneer, Submarine reconnaissance, Naval Strike Fighters and R.A.F. Trainers as exemplified by the Gannet, Wyvern and Provost.