478 research outputs found
Rationing of Treatment for Varicose Veins and Use of New Treatment Methods: A Survey of Practice in the United Kingdom
IntroductionThis study aimed to document the extent of rationing of treatment for varicose veins in the United Kingdom (UK) national health services and the extent to which new treatments are being used.ReportCompleted questionnaires were received from 75% (307/411) vascular surgeons from all areas of the UK. 46% restricted access to treatment – 13% in the absence of local referral guidance. 76% would treat patients privately who did not fulfil their health service criteria. In the health service vs private practice, foam sclerotherapy was used by 28 vs 42; radiofrequency ablation by 8 vs 30; and laser ablation by 16 vs 22.DiscussionRationing of health service treatment for varicose veins is common in the UK. More explicit selection criteria are required for introduction of new treatments and reconfigured services
Occlusion of the Popliteal Artery in Hereditary Multiple Exostosis Syndrome
AbstractIntroductionHereditary multiple exostosis syndrome is a rare condition which can occasionally cause arterial occlusion.Case reportA 50-year-old man was treated for acute leg ischaemia but no cause found. Two years later, acute ischaemia recurred and attempts at limb salvage failed. Hereditary multiple exostosis syndrome was then recognised as the cause due to a femoral exostosis compressing the popliteal artery.DiscussionThe case highlights a rare cause of acute limb ischaemia and emphasises the importance of arterial imaging when no embolic source is found
The Symptoms of Varicose Veins: Difficult to Determine and Difficult to Study
ObjectivesTo investigate the activities which may exacerbate symptoms in patients with varicose veins.MethodsQuestionnaires sent to patients before clinics and at least six months later.ResultsBoth questionnaires were returned by 149 of 203 patients (74%) but only 124 contained adequate data for comparison – 55 from patients who had surgical treatment and 69 who had no surgery. At initial presentation, worsening of discomfort attributed to varicose veins was common during (58%) or after (48%) standing and in hot weather (44%), but less when sitting with the feet down (31%), and after (31%) or when walking (19%). Surgery significantly reduced the total number of symptoms reported by patients at follow-up (p<0.02). However, none of the symptoms reported during specific activities was significantly lessened by surgery compared with no treatment – possibly because the attrition of patients during the study resulted in small numbers for analysis.ConclusionsSymptoms are a common indication for treating varicose veins and it is therefore important to be sure that they are due to the veins, rather than other causes. This report highlights traditional and logical questions which may help to identify symptoms caused by varicose veins but illustrates the difficulty of validating them
Connecting global priorities: biodiversity and human health: a state of knowledge review.
Healthy communities rely on well-functioning ecosystems. They provide clean air, fresh water, medicines and food security. They also limit disease and stabilize the climate. But biodiversity loss is happening at unprecedented rates, impacting human health worldwide.The report, Connecting Global Priorities: Biodiversity and Human Health, focuses on the complex and multi-faceted connections between biodiversity and human health, and how the loss of biodiversity and corresponding ecosystem services may negatively influence health. One of the first integrative reviews of its kind, the report brings together knowledge from several scientific disciplines, including public health, conservation, agriculture, epidemiology and development. The book is a joint publication of the Convention on Biological Diversity and World Health Organization. Danny Hunter, Senior Scientist, Bioversity International is one of the Lead Coordinating Authors of the book and co-lead author on two chapters:Chapter 5: Agricultural biodiversity and food security Chapter 6: Biodiversity and nutritio
Variational Approximations in a Path-Integral Description of Potential Scattering
Using a recent path integral representation for the T-matrix in
nonrelativistic potential scattering we investigate new variational
approximations in this framework. By means of the Feynman-Jensen variational
principle and the most general ansatz quadratic in the velocity variables --
over which one has to integrate functionally -- we obtain variational equations
which contain classical elements (trajectories) as well as quantum-mechanical
ones (wave spreading).We analyse these equations and solve them numerically by
iteration, a procedure best suited at high energy. The first correction to the
variational result arising from a cumulant expansion is also evaluated.
Comparison is made with exact partial-wave results for scattering from a
Gaussian potential and better agreement is found at large scattering angles
where the standard eikonal-type approximations fail.Comment: 35 pages, 3 figures, 6 tables, Latex with amsmath, amssymb; v2: 28
pages, EPJ style, misprints corrected, note added about correct treatment of
complex Gaussian integrals with the theory of "pencils", matches published
versio
Organic film thickness influence on the bias stress instability in Sexithiophene Field Effect Transistors
In this paper, the dynamics of bias stress phenomenon in Sexithiophene (T6)
Field Effect Transistors (FETs) has been investigated. T6 FETs have been
fabricated by vacuum depositing films with thickness from 10 nm to 130 nm on
Si/SiO2 substrates. After the T6 film structural analysis by X-Ray diffraction
and the FET electrical investigation focused on carrier mobility evaluation,
bias stress instability parameters have been estimated and discussed in the
context of existing models. By increasing the film thickness, a clear
correlation between the stress parameters and the structural properties of the
organic layer has been highlighted. Conversely, the mobility values result
almost thickness independent
Post-Newtonian Gravitational Radiation
1 Introduction 2 Multipole Decomposition 3 Source Multipole Moments 4
Post-Minkowskian Approximation 5 Radiative Multipole Moments 6 Post-Newtonian
Approximation 7 Point-Particles 8 ConclusionComment: 46 pages, in Einstein's Field Equations and Their Physical
Implications, B. Schmidt (Ed.), Lecture Notes in Physics, Springe
Equations for the estimation of strong ground motions from shallow crustal earthquakes using data from Europe and the Middle East : vertical peak ground acceleration and spectral acceleration
This article presents equations for the estimation of vertical strong ground motions caused by shallow crustal earthquakes with magnitudes M w 5 and distance to the surface projection of the fault less than 100km. These equations were derived by weighted regression analysis, used to remove observed magnitude-dependent variance, on a set of 595 strong-motion records recorded in Europe and the Middle East. Coefficients are included to model the effect of local site effects and faulting mechanism on the observed ground motions. The equations include coefficients to model the observed magnitude-dependent decay rate. The main findings of this study are that: short-period ground motions from small and moderate magnitude earthquakes decay faster than the commonly assumed 1/r, the average effect of differing faulting mechanisms is similar to that observed for horizontal motions and is not large and corresponds to factors between 0.7 (normal and odd) and 1.4 (thrust) with respect to strike-slip motions and that the average long-period amplification caused by soft soil deposits is about 2.1 over those on rock sites
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