Treatment of endobronchial metastases with intraluminal radiotherapy

AbstractMetastasis to the lung occurs quite commonly from certain types of extrapulmonary primary carcinoma. Spread to the bronchial lumen is relatively rare. When this does occur, symptoms resembling those of primary bronchial carcinoma are often present, in association with partial or complete obstruction of the bronchial lumen. Palliation of such symptoms is possible with the use of intraluminal radiotherapy (ILT). Between 1990 and 1998, 37 patients with endobronchial metastases were treated using this modality; a single fraction of radiation was delivered by the remote afterloading high dose rate microSelectron system. Data regarding these patients' characteristics and outcome are presented, following a retrospective review of case notes.The commonest symptoms were dyspnoea, cough and haemoptysis; the commonest primary tumour sites were breast, colorectum, oesophagus and kidney. Twenty-four (64·9%) patients had some improvement in symptoms following treatment. Mean overall survival was 280 days, range 9–1145 days. No serious adverse effects occurred. ILT is a relatively simple, safe and effective treatment in the palliation of symptoms due to endobronchial metastases

The Universlity Class of Monopole Condensation in Non-Compact, Quenched Lattice QED

Finite size scaling studies of monopole condensation in noncompact quenched lattice $QED$ indicate an authentic second order phase transition lying in the universality class of four dimensional percolation. Since the upper critical dimension of percolation is six, the measured critical indices are far from mean-field values. We propose a simple set of ratios as the exact critical indices for this transition. The implication of these results for critical points in Abelian gauge theories are discussed.Comment: ILL-(TH)-92-6, CERN-TH.6515/92, 10 pages, no figures available as PS fil

Summer Sea Ice Concentration, Motion, and Thickness Near Areas of Proposed Offshore Oil and Gas Development in the Canadian Beaufort Sea – 2009

This study was motivated by the potential development of offshore oil exploration leases in the Canadian Southern Beaufort Sea, an area within the Inuvialuit Settlement Region. Sea ice concentration, extent, motion, and thickness data are vital to the success of potential oil operations in this region, and relevant data cannot be gleaned from larger-scale hemispheric studies. We therefore undertook regionally specific sea ice analyses in the southern Beaufort Sea during the summer drilling season (July, August, and September) in 2009 and over the long-term (1996 – 2010). On average, the Canadian oil lease areas contain mostly old sea ice during the drilling season and have not experienced significant decreasing trends in total or old sea ice. The average sea ice motion in the region for the period was anti-cyclonic at 20 – 25 cm·s-1, acting to transport sea ice southward toward the lease areas. Summer 2009 was used as a case study of regional ice concentration, motion, and thickness and to compare September sea ice thickness measurements to data collected in April 2009. In the summer of 2009, old sea ice was the predominant ice type in the lease areas. Sea ice motion was anti-cyclonic and faster than the long-term average, reaching 60 cm·s-1 west of Banks Island and across the north end of the lease areas. September 2009 sea ice thickness (mean = 1.03 m, σ = 0.97 m) was modal about the 0.20 – 0.29 m thickness bin. The sea ice thickness distri­bution was spatially variable, with the thickest ice occurring at the north end of the study area, in an area dominated by high old ice concentrations. Ice thicknesses greater than 10 m (the upper limit our instruments could measure) were encountered. Thinner sea ice predominated at the periphery of the core Beaufort Sea multi-year pack. Near the oil lease areas, the sea ice thickness distributions were shifted left on the histogram in comparison to those farther north, resulting in a greater proportion of relatively thick sea ice due to the thermodynamic loss of thinner (< 1.5 m) first-year ice during its southward movement. After enduring a summer’s melt, however, this thicker ice at the south end of the study region had thinned in comparison to the ice at the north end.La présente étude a été motivée par la mise en valeur potentielle des concessions d’exploration pétrolière au large de la mer de Beaufort, dans la partie sud canadienne, un endroit qui fait partie de la région désignée des Inuvialuit. Les données relatives à la concentration, à l’étendue, au déplacement et à l’épaisseur de la glace de mer sont essentielles à la réussite de l’exploitation éventuelle du pétrole dans cette région, et les données pertinentes ne peuvent être dépouillées à partir d’études hémisphériques réalisées à grande échelle. Par conséquent, nous avons entrepris de faire des analyses particulièrement régionales de la glace de mer du sud de la mer de Beaufort pendant la saison de forage d’été (juillet, août et septembre) en 2009 de même que sur une plus longue période (1996-2010). En moyenne, les régions visées par les concessions pétrolières canadiennes renferment principalement de la vieille glace de mer pendant la saison de forage, et elles n’enregistrent pas d’importantes tendances à la baisse sur le plan de l’ensemble de la glace de mer ou de la vieille glace de mer. Dans la région, le déplacement moyen de la glace de mer pendant la période était anticyclonique à 20 25 cm·s-1, ce qui avait pour effet de transporter la glace de mer vers le sud et vers les concessions. L’été 2009 nous a servi d’étude de cas en matière de concentration, de déplacement et d’épaisseur de la glace régionale, et nous a permis de comparer les mesures de l’épaisseur de la glace de mer de septembre aux données recueillies en avril 2009. À l’été 2009, la vieille glace de mer représentait le type de glace prédominant dans les concessions. Le déplacement de la glace de mer était anticyclonique et se faisait plus vite que la moyenne à long terme, atteignant ainsi 60 cm·s-1 à l’ouest de l’île Banks et à la hauteur du nord de la zone de concessions. En septembre 2009, l’épaisseur de la glace de mer (moyenne = 1,03 m, σ = 0,97 m) était modale à la hauteur de la classe de l’épaisseur 0,20 – 0,29 m. La répartition de l’épaisseur de la glace de mer variait en fonction de l’emplacement, la glace la plus épaisse se trouvant du côté nord de la région étudiée, dans une zone dominée par de fortes concentrations de vieille glace. La glace atteignait des épaisseurs de plus de 10 m (la limite maximale que nos instruments pouvaient mesurer) par endroits. Une glace de mer plus mince prédominait la périphérie du noyau de la banquise pluriannuelle de la mer de Beaufort. Près de la zone de concessions pétrolières, les répartitions d’épaisseurs de glace de mer se sont déplacées vers la gauche sur l’histogramme comparativement à celles plus au nord, ce qui a donné une plus grande proportion de glace de mer relativement épaisse en raison de la perte thermodynamique de la glace plus mince de première année (< 1,5 m) pendant son déplacement vers le sud. Cependant, après avoir enduré la fonte d’un été, la glace plus épaisse du côté sud de la région à l’étude s’était amincie compara­tivement à la glace se trouvant du côté nord

An Alternative Method to Deduce Bubble Dynamics in Single Bubble Sonoluminescence Experiments

In this paper we present an experimental approach that allows to deduce the important dynamical parameters of single sonoluminescing bubbles (pressure amplitude, ambient radius, radius-time curve) The technique is based on a few previously confirmed theoretical assumptions and requires the knowledge of quantities such as the amplitude of the electric excitation and the phase of the flashes in the acoustic period. These quantities are easily measurable by a digital oscilloscope, avoiding the cost of expensive lasers, or ultrafast cameras of previous methods. We show the technique on a particular example and compare the results with conventional Mie scattering. We find that within the experimental uncertainties these two techniques provide similar results.Comment: 8 pages, 5 figures, submitted to Phys. Rev.

Direct Extraction of QCD Lambda MS-bar from e+e- Jet Observables

We directly fit the QCD dimensional transmutation parameter, Lambda MS-bar, to experimental data on e+e- jet observables, making use of next-to-leading order (NLO) perturbative calculations. In this procedure there is no need to mention, let alone to arbitrarily vary, the unphysical renormalisation scale mu, and one avoids the spurious and meaningless ``theoretical error'' associated with standard alpha_s determinations. PETRA, SLD, and LEP data are considered in the analysis. An attempt is made to estimate the importance of uncalculated next-NLO and higher order perturbative corrections, and power corrections, by studying the scatter in the values of Lambda MS-bar obtained for different observables.Comment: 46 pages, 22 figure

Evidence for exercise-based interventions across 45 different long-term conditions: An overview of systematic reviews

Background Almost half of the global population face significant challenges from long-term conditions (LTCs) resulting in substantive health and socioeconomic burden. Exercise is a potentially key intervention in effective LTC management. Methods In this overview of systematic reviews (SRs), we searched six electronic databases from January 2000 to October 2023 for SRs assessing health outcomes (mortality, hospitalisation, exercise capacity, disability, frailty, health-related quality of life (HRQoL), and physical activity) related to exercise-based interventions in adults (aged >18 years) diagnosed with one of 45 LTCs. Methodological quality was assessed using AMSTAR-2. International Prospective Resister of Systematic Reviews (PROSPERO) ID: CRD42022319214. Findings Forty-two SRs plus three supplementary RCTs were included, providing 990 RCTs in 936,825 people across 39 LTCs. No evidence was identified for six LTCs. Predominant outcome domains were HRQoL (82% of SRs/RCTs) and exercise capacity (66%); whereas disability, mortality, physical activity, and hospitalisation were less frequently reported (≤25%). Evidence supporting exercise-based interventions was identified in 25 LTCs, was unclear for 13 LTCs, and for one LTC suggested no effect. No SRs considered multimorbidity in the delivery of exercise. Methodological quality varied: critically-low (33%), low (26%), moderate (26%), and high (12%). Interpretation Exercise-based interventions improve HRQoL and exercise capacity across numerous LTCs. Key evidence gaps included limited mortality and hospitalisation data and consideration of multimorbidity impact on exercise-based interventions. Funding This study was funded by the National Institute for Health and Care Research (NIHR; Personalised Exercise-Rehabilitation FOR people with Multiple long-term conditions (multimorbidity)—NIHR202020)

On the two-dimensional solution of both adhesive and non-adhesive contact problems involving functionally graded materials

This paper presents a semi-analytical algorithm for the determination of the contact half width and surface pressure which results from both adhesive and non-adhesive contact problems involving functionally graded materials (FGM). The inhomogeneously elastic solid comprises a graded elastic coating whose shear modulus depends exponentially on the vertical coordinate and a homogeneously elastic substrate. The solid is assumed to be in a state of plane strain and thus a two-dimensional analysis is performed within this work. Using the work of Chidlow et al. (2011a) as a starting point, we derive a pair of integral equations which may be used to determine approximations to the contact pressure when either the surface deflection or the deflection gradient is known over the contact region. As these integral equations are non-singular, we use Galerkin's method to approximate the contact pressure and it is found that relatively small trial spaces allow accurate computation of the pressure. Information about the prescribed load is then used to formulate an iterative algorithm to determine the contact half width. A selection of numerical results are presented using this method and it is found that the solutions computed here compare favourably with those of other authors. A further investigation is then conducted into the solution of adhesive contact problems using the assumptions of Maugis (1992) and Johnson and Greenwood (2008) to inform the nature of the adhesive stresses outside of the contact. It is found that both JKR-like and DMT-like behaviour can be observed in contact problems involving FGMs

A solution method for the sub-surface stresses and local deflection of a semi-infinite inhomogeneous elastic medium

This paper proposes analytical Fourier series solutions (based on the Airy stress function) for the local deflection and subsurface stress field of a two-dimensional graded elastic solid loaded by a pre-determined pressure distribution. We present a selection of numerical results for a simple sinusoidal pressure which indicates how the inhomogeneity of the solid affects its behaviour. The model is then adapted and used to derive an iterative algorithm which may be used to solve for the contact half width and pressure induced from contact with a rigid punch. Finally, the contact of a rigid cylindrical stamp is studied and our results compared to those predicted by Hertzian theory. It is found that solids with a slowly varying elastic modulus produce results in good agreement with those of Hertz whilst more quickly varying elastic moduli which correspond to solids that become stiffer below the surface give rise to larger maximum pressures and stresses whilst the contact pressure is found to act over a smaller area