Publications by authors named "Burt G"

Article Synopsis
  • - The Lancet Oncology Commission focuses on improving global access to radiotherapy and theranostics, addressing significant disparities between high-income countries and low-income and middle-income countries (LMICs) concerning available treatment resources and trained healthcare professionals.
  • - The implementation of hypofractionation techniques in radiotherapy could increase treatment access for millions of patients with prostate and breast cancer, highlighting the need for new technologies in LMICs with existing resources.
  • - A global survey revealed variability in the use of radiopharmaceutical therapy, with issues related to supply chains and workforce training impacting access; initiatives like the International Atomic Energy Agency's Rays of Hope program and investment from development banks are encouraged to improve the situation.
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Background: Although natural rubber latex remains dominant as the primary manufacturing material for male condoms synthetic materials first introduced in the early 1990s address many of the limitations of latex including the risk of allergies. Polyurethane elastomers allow condoms to be made significantly thinner to provide greater sensitivity and encourage greater use of condoms for contraception and STI prophylaxis. The primary objective of this Study was to evaluate the breakage, slippage and acceptability of two ultra-thin polyurethane condoms against a thin control latex male condom, designated latex C, in a randomized, cross over, masked, non-inferiority study.

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Periodically-poled lithium niobate (PPLN) sources consisting of custom-built stacks of large-area wafers provide a unique opportunity to systematically study the multi-cycle terahertz (THz) generation mechanism as they are assembled layer-by-layer. Here we investigate and optimize the THz emission from PPLN wafer stacks as a function of wafer number, pump fluence, pulse duration and chirp, wafer separation, and pump focusing. Using 135 µm-thick, 2"-diameter wafers we generate high-energy, narrowband THz pulses with central frequencies up to 0.

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Superconducting Radio-Frequency cavities are currently made out of niobium. Niobium cavities are limited by the magnetic field on the cavity walls due to the entry of vortices at the field of first vortex penetration, H[Formula: see text]. Low temperature baking in vacuum or low pressure gas atmosphere removes the strong decrease of the quality factor with accelerating gradient (high field Q-slope).

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Radiation therapy is a critical component for curative and palliative treatment of cancer and is used in more than half of all patients with cancer. Yet there is a global shortage of access to this treatment, especially in Sub-Saharan Africa, where there is a shortage of technical staff as well as equipment. Linear accelerators (LINACs) offer state-of-the-art treatment, but this technology is expensive to acquire, operate and service, especially for low- and middle-income countries (LMICs), and often their harsh environment negatively affects the performance of LINACs, causing downtime.

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In this article, we briefly summarize the experiments performed during the first run of the Advanced Wakefield Experiment, AWAKE, at CERN (European Organization for Nuclear Research). The final goal of AWAKE Run 1 (2013-2018) was to demonstrate that 10-20 MeV electrons can be accelerated to GeV energies in a plasma wakefield driven by a highly relativistic self-modulated proton bunch. We describe the experiment, outline the measurement concept and present first results.

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We measure the effects of transverse wakefields driven by a relativistic proton bunch in plasma with densities of 2.1×10^{14} and 7.7×10^{14}  electrons/cm^{3}.

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We give direct experimental evidence for the observation of the full transverse self-modulation of a long, relativistic proton bunch propagating through a dense plasma. The bunch exits the plasma with a periodic density modulation resulting from radial wakefield effects. We show that the modulation is seeded by a relativistic ionization front created using an intense laser pulse copropagating with the proton bunch.

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High-energy particle accelerators have been crucial in providing a deeper understanding of fundamental particles and the forces that govern their interactions. To increase the energy of the particles or to reduce the size of the accelerator, new acceleration schemes need to be developed. Plasma wakefield acceleration, in which the electrons in a plasma are excited, leading to strong electric fields (so called 'wakefields'), is one such promising acceleration technique.

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Data on the vigour and at-vessel mortality (AVM) of 6798 skates (comprising Raja clavata n = 6295; R. brachyura n = 208; R. undulata n = 185, R.

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Background: Significant developments have occurred in the design of resin-bonded bridges (RBB) over the past two decades. They are commonly used as an alternative treatment option for a single missing tooth. The longevity of these bridges needs to be further investigated to evaluate long-term outcomes for this option to remain relevant.

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The best estimate of risk to a population group resulting from internal exposure to a particular radionuclide can be used to assess the reliability of the appropriate International Commission on Radiological Protection (ICRP) dose coefficient (E⁵⁰) for the specified exposure pathway. An estimate of the uncertainty on the risk is important for reliability decisions. This paper describes the application of parameter uncertainty analysis to quantify uncertainties resulting from internal exposures to uranium (as (²³⁸U) by members of the public.

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We report studies of ultrahigh-energy cosmic-ray composition via analysis of depth of air shower maximum (X(max)), for air shower events collected by the High-Resolution Fly's Eye (HiRes) observatory. The HiRes data are consistent with a constant elongation rate d/d[log(E)] of 47.9+/-6.

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Although the standard karyotype of the western house mouse (Mus musculus domesticus) consists entirely of telocentric chromosomes, there are over 100 populations across western Europe and North Africa characterized by different sets of metacentrics formed by Robertsonian fusions and whole-arm reciprocal translocations. Here we report the discovery of a new metacentric population from Valchiavenna, northern Italy, that we have named the 'Lower Valchiavenna population' (abbreviated as ILVC). This metacentric population is found in villages and on farms over a 10-kilometer stretch comprising the southern half of Valchiavenna.

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The High Resolution Fly's Eye (HiRes) experiment has observed the Greisen-Zatsepin-Kuzmin suppression (called the GZK cutoff) with a statistical significance of five standard deviations. HiRes' measurement of the flux of ultrahigh energy cosmic rays shows a sharp suppression at an energy of 6 x 10(19) eV, consistent with the expected cutoff energy. We observe the ankle of the cosmic-ray energy spectrum as well, at an energy of 4 x 10(18) eV.

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Biological effects monitoring has seldom been undertaken in offshore pelagic environments. Cages containing hatchery-reared Atlantic cod Gadus morhua were deployed on expected contamination gradients, along a transect from the River Elbe in the German Bight, and in the vicinity of an oil field in the North Sea (Statfjord). Six weeks later, the cod were retrieved and samples taken for a range of biological effects techniques.

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We have assessed whether an epidural steroid injection is effective in the treatment of symptoms due to compression of a nerve root in the lumbar spine by carrying out a prospective, randomised, controlled trial in which patients received either an epidural steroid injection or an intramuscular injection of local anaesthetic and steroid. We assessed a total of 93 patients according to the Oxford pain chart and the Oswestry disability index and followed up for a minimum of two years. All the patients had been categorised as potential candidates for surgery.

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Concentrations and composition of butyltin (BT) and phenyltin (PT) compounds were compared in tissues of mussels Mytilus edulis and clams Mya arenaria collected from the Mersey Estuary. Tributyltin (TBT) concentrations were consistently highest in digestive gland and low in muscular tissues such as siphons (Mya) and adductor muscle (Mytilus). Lowest concentrations were found in the periostracum surrounding the siphons of Mya.

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Background: Using commercial computer graphics software (TrueSpace), we constructed a virtual-reality model for teaching interscalene brachial plexus block. This tool combines the clarity of schematic drawings and the clinical relevance of video clips and live demonstrations. The aim is to accelerate learning and aid retention of relevant information.

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Helically corrugated waveguides have recently been studied for use in various applications such as interaction regions in gyrotron traveling-wave tubes and gyrotron backward-wave oscillators and as a dispersive medium for passive microwave pulse compression. The paper presents a summary of various methods that can be used for analysis of the wave dispersion of such waveguides. The results obtained from an analytical approach, simulations with the three-dimensional numerical code MAGIC, and cold microwave measurements are analyzed and compared.

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A new method to generate ultrahigh-power microwave pulses compatible with mildly relativistic electron sources is proposed. This method involves a novel microwave compressor in the form of a metal helically corrugated waveguide, which can enhance the power of frequency-modulated nanosecond pulses up to the multigigawatt level. The results of the proof-of-principle experiments at kilowatt power levels are in good agreement with theory.

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Recovery of marine ecosystems from pollution has tended to receive less attention than the study of new or continuing impacts, but such studies are important in charting recovery from acute incidents and following legislation to deal with chronic contamination. Recovery is inevitably a long-term process, and where such studies have been made they are often too short-lived. Interest quickly wanes following an acute incident and governmental bodies rapidly switch to new legislative priorities for chronic inputs.

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