Summary
Background: Castration‐resistant prostate cancer (CRPC) is an advanced form of prostate cancer associated with poor survival rates. However, characterisation of the disease epidemiology is ...hampered by use of varying terminology, definition and disease management. The aim of this review was to conduct a systematic review to provide greater clarity on the sum of the available epidemiologic evidence and to guide future research into the disease prevalence, progression, characteristics and outcome.
Methods: Systematic searches of PubMed and Embase were performed in March 2010 to identify relevant observational studies relating to the epidemiology, progression and outcomes of CRPC. Further studies were identified for inclusion in our review through manual searches of the authors’ bibliographical databases and the reference lists of the included articles.
Results: We identified 12 articles (10 full papers and 2 s) reporting studies that included a total of 71,179 patients observed for up to 12 years for evaluation in our review. Five studies looked at the prevalence of CRPC in patients with prostate cancer. Together, the data indicate that 10–20% of prostate cancer patients develop CRPC within approximately 5 years of follow‐up. Two studies reported the prevalence of bone metastases present at diagnosis of CRPC. Together, ≥ 84% were shown to have metastases at diagnosis. Of those patients with no metastases present at diagnosis of CRPC, 33% could expect to develop them within 2 years. The median survival of patients with CRPC was reported in five studies, with values varying from 9 to 30 months. A pooled, sample‐weighted survival estimate calculated from the survival data included in this review is 14 months. Very few studies that met our inclusion criteria evaluated treatment patterns in CRPC. One study reported that only 37% of patients with CRPC received chemotherapy, with the remainder receiving only steroids and supportive care. The most common palliative therapies administered to patients with skeletal symptoms were radiotherapy, radionuclide therapy, bisphosphonates and opioids.
Conclusions: This review highlights the poor prognosis of patients with CRPC, and demonstrates a survival of 9–13 months in those patients with metastatic CRPC. Furthermore, progression to CRPC is associated with deterioration in quality of life, and few therapeutic options are currently available to patients with CRPC. However, epidemiologic study of these patients is hampered by differing terminology, definitions and treatment paradigms. Our review highlights the need for further well‐designed, epidemiological studies of CRPC, using standardised definitions and methods.
Ensembles of numerical simulations are used in a variety of applications, such as meteorology or computational solid mechanics, in order to quantify the uncertainty or possible error in a model or ...simulation. Deriving robust statistics and visualizing the variability of an ensemble is a challenging task and is usually accomplished through direct visualization of ensemble members or by providing aggregate representations such as an average or pointwise probabilities. In many cases, the interesting quantities in a simulation are not dense fields, but are sets of features that are often represented as thresholds on physical or derived quantities. In this paper, we introduce a generalization of boxplots, called contour boxplots, for visualization and exploration of ensembles of contours or level sets of functions. Conventional boxplots have been widely used as an exploratory or communicative tool for data analysis, and they typically show the median, mean, confidence intervals, and outliers of a population. The proposed contour boxplots are a generalization of functional boxplots, which build on the notion of data depth. Data depth approximates the extent to which a particular sample is centrally located within its density function. This produces a center-outward ordering that gives rise to the statistical quantities that are essential to boxplots. Here we present a generalization of functional data depth to contours and demonstrate methods for displaying the resulting boxplots for two-dimensional simulation data in weather forecasting and computational fluid dynamics.
This article surveys the history and current state of the art of visualization in meteorology, focusing on visualization techniques and tools used for meteorological data analysis. We examine ...characteristics of meteorological data and analysis tasks, describe the development of computer graphics methods for visualization in meteorology from the 1960s to today, and visit the state of the art of visualization techniques and tools in operational weather forecasting and atmospheric research. We approach the topic from both the visualization and the meteorological side, showing visualization techniques commonly used in meteorological practice, and surveying recent studies in visualization research aimed at meteorological applications. Our overview covers visualization techniques from the fields of display design, 3D visualization, flow dynamics, feature-based visualization, comparative visualization and data fusion, uncertainty and ensemble visualization, interactive visual analysis, efficient rendering, and scalability and reproducibility. We discuss demands and challenges for visualization research targeting meteorological data analysis, highlighting aspects in demonstration of benefit, interactive visual analysis, seamless visualization, ensemble visualization, 3D visualization, and technical issues.
The SAXS/WAXS beamline at the Australian Synchrotron is an advanced and flexible undulator X‐ray scattering beamline used for small‐ and wide‐angle X‐ray scattering analysis on a wide variety of ...solids, fluids and surfaces across a diverse range of research and development fields. The beamline has numerous features that minimize the intensity of the instrument background, provide automated stable optics, and allow accurate analysis of very weakly scattering samples. The geometric and intensity requirements of a three‐slit collimation system are described in detail for conventional metal and single‐crystal germanium slits. Straightforward ray tracing and simple linear projections describe the observed direct beam as well as parasitic background scattering geometry of the beamline at its longest camera length, providing a methodology for the design and operation of similar beamlines. As an aid to instrument design, the limit of background intensity determined by the intensity incident on single‐crystal germanium guard slit edges and its q dependence was quantified at 11 keV. Details of the beamline's implementation, underlying optical concept and measured performance are given.
Gaussian processes (GP) form a well-established predictive tool which provides a natural platform for tackling high-dimensional random input data in challenging simulations. This paper introduces a ...generic framework for integrating Gaussian Processes with risk-based structural optimization. We solve robust and reliability-based design problems in the context of stress-based topology optimization under imperfections in geometry and material properties, and loading variability. We construct independent GPs for primal and adjoint quantities, namely the global maximum von Mises stress and its sensitivity where we enhance the computational efficiency by leveraging the information from multiresolution finite element simulations. The GP framework naturally lends itself to modeling noise in data. We investigate the effect of numerical modeling error in high-fidelity simulations via a noisy GP emulator and provide a pareto curve that shows the robustness of optimal design with respect to the noise level. We provide a posteriori error estimates that quantify the discrepancy between the noisy emulator and true simulations, and verify them with a numerical study. We demonstrate our approach on a benchmark L-shape structure which exhibits stress concentration, a compliant mechanism design and a heat sink design. We also provide practical guidelines for estimation of failure probability and its sensitivity to facilitate reliability-based topology optimization.
Mixed nanoparticle-surfactant systems are effective foam stabilizing agents, but the lack of colloidal stability of the bulk dispersions makes interfacial characterization challenging. This study ...investigates the adsorption of C
TAB/SiO
complexes at air/water interfaces through surface tension and interfacial rheology measurements. The effects of surfactant tail length, ionic strength, and interfacial processing on the surface properties are measured utilizing a bulk reservoir exchange methodology to avoid bulk destabilization. The surfactant structure controls the surface tension of the system, but has minimal impact on particle surface coverage or interfacial mechanics. Once adsorbed, nanoparticles remain pinned at the surface, while the surfactant is able to desorb upon bulk exchange with deionized water. Particle packing on the interface governs the interfacial mechanics, which can be modified by increasing the ionic strength of the bulk solution. Fully rigid interfaces can be generated at low particle coverages by controlling the ionic strength and interfacial processing. These findings contribute to the understanding of mixed particle-surfactant systems and inform formulation and process design to achieve the desired interfacial mechanical properties.
The probable effect of climate change on the water available for use in Bangladesh is not well known. We calculate monthly water balances for five main regions of Bangladesh to examine the likely ...impacts of climate change to 2050. We also examine the impact of past and potential future irrigation development. Climate change projections for rainfall in Bangladesh are uncertain, with increased rain in the wet season likely, but decreased rain also possible. Runoff is projected to vary in a manner similar to rainfall. However, assuming no change to the area of crops, all projections result in increases in irrigation water use, which leads to groundwater level declines. The impact of change (whether climate change or development) on water availability and use is greater in the Northwest region than elsewhere. For most water balance terms in most regions, irrigation development (both historic and future) is calculated to have a larger impact than climate change. Climate change is calculated to have a larger impact than irrigation development only on evapotranspiration and runoff, and possibly on groundwater levels. Model sensitivity tests suggest that model uncertainty is less than climate change uncertainty. To reverse lowered groundwater levels, Bangladesh’s policy includes greater use of surface water. While we calculate groundwater levels will rise, the viability of the policy may be affected by future changes to upstream use.
Enhancing crop production, particularly by growing a crop in the typically-fallow dry season is a key strategy for alleviating poverty in the Ganges delta region. We used a polder water and salt ...balance model to examine the impact of several crop management, salt management and climate change scenarios on salinity and crop evapotranspiration at Dacope and Amtali in Bangladesh and Gosaba in India. A key (and unsurprising) finding is that salt management is very important, particularly at the two drier sites, Dacope and Gosaba. Good salt management lowers salinity in the shallow groundwater, soil and water storage ponds, and leads to more irrigation. Climate change is projected to alter rainfall, and this in turn leads to modelled increases or decreases in runoff from the polders, and thence affect salt concentrations in the soil and ponds and canals. Thus, the main impacts of climate change are through the indirect impacts on salt concentrations, rather than the direct impacts of the amount of water supplied as rainfall. Management practices to remove salt from polders are therefore likely to be effective in combatting the impacts of projected climate change particularly at Dacope and Gosaba.
Recent efforts to model tricalcium silicate based cements assume a two-step hydration mechanism where, in the first step, the empty space between cement particles rapidly fills with a low density ...calcium silicate hydrate (C-S-H) and in the second step, the thus formed C-S-H densifies slowly. This gives rise to models that nicely mimic the shape of experimentally observed hydration calorimetry curves and explains the transition between Stage 3 (acceleration) and Stage 4 (decreasing rate) hydration as well as post Stage 4 continued slow reaction. If this mechanism is correct, however, one would expect that the amount of heat energy released should increase with available space between particles, i.e. with water-to-cement ratio. A series of experiments, wherein the water-to-cement ratio was systematically varied showed little or no increase in total heat released when the water-to-cement ratio was doubled or tripled suggesting that the two-step mechanism may need revision.