28 research outputs found

    Global surveillance of cancer survival 1995-2009: analysis of individual data for 25,676,887 patients from 279 population-based registries in 67 countries (CONCORD-2)

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    BACKGROUND: Worldwide data for cancer survival are scarce. We aimed to initiate worldwide surveillance of cancer survival by central analysis of population-based registry data, as a metric of the effectiveness of health systems, and to inform global policy on cancer control. METHODS: Individual tumour records were submitted by 279 population-based cancer registries in 67 countries for 25·7 million adults (age 15-99 years) and 75,000 children (age 0-14 years) diagnosed with cancer during 1995-2009 and followed up to Dec 31, 2009, or later. We looked at cancers of the stomach, colon, rectum, liver, lung, breast (women), cervix, ovary, and prostate in adults, and adult and childhood leukaemia. Standardised quality control procedures were applied; errors were corrected by the registry concerned. We estimated 5-year net survival, adjusted for background mortality in every country or region by age (single year), sex, and calendar year, and by race or ethnic origin in some countries. Estimates were age-standardised with the International Cancer Survival Standard weights. FINDINGS: 5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005-09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15-19% in North America, and as low as 7-9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10-20% between 1995-99 and 2005-09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995-99 and 2005-09 have generally been slight. For women diagnosed with ovarian cancer in 2005-09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005-09 was high (54-58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18-23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease. INTERPRETATION: International comparison of survival trends reveals very wide differences that are likely to be attributable to differences in access to early diagnosis and optimum treatment. Continuous worldwide surveillance of cancer survival should become an indispensable source of information for cancer patients and researchers and a stimulus for politicians to improve health policy and health-care systems

    Ground motions induced by pore pressure changes at the Szentes geothermal area, SE Hungary

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    Excessive thermal water volumes have been extracted from porous sedimentary rocks in the Hungarian part of the Pannonian Basin. Thermal water production in Hungary increased significantly from the early 1970s. Regional-scale exploitation of geothermal reservoirs without re-injection resulted in basin-scale pressure drop in the Upper Pannonian (Upper Miocene) sediments, leading to compaction. This compaction resulted in ground subsidence primarily through poro-elastic coupling. We investigated surface deformation at the Szentes geothermal filed, SE Hungary, where the largest pressure decline occurred. Subsequently, hydraulic head recovery in the western part of the geothermal reservoir was initiated in the mid-1990s. We obtained data from the European Space Agency’s Envisat satellites to estimate the ground motions for the period of November 2002–December 2006. We applied inverse geomechanical modeling to estimate reservoir properties and processes. We constrained the model parameters using the Ensemble Smoother with Multiple Data Assimilation, which allowed us to incorporate large amounts of surface movement observations in a computationally efficient way. Ground movements together with the modeling results show that uplift of the Szentes geothermal field occurred during the observation period. Since no injection wells were operated at Szentes before 2018, and production temperatures remained relatively constant through the entire production period, we explain ground uplift with pore pressure increase due to natural recharge. The estimated decompaction coefficients of the reservoir system characterizing the elastic behavior of the Szentes geothermal reservoir varies between ~ 0.2 × 10–9 and 2 × 10–9 Pa−1. Compaction coefficients of the reservoir system corresponding to the earlier depressurization period, from ~ 1970 to the mid-1990s, may be significantly larger due to the potential inelastic behavior and permanent compaction of clay-rich aquitards. The improved parametrization enables better forecasting of the reservoir behavior and facilitates the assessment of future subsidence scenarios that are helpful for the establishment of a sustainable production scheme

    Ground motions induced by pore pressure changes at the Szentes geothermal area, SE Hungary

    No full text
    Excessive thermal water volumes have been extracted from porous sedimentary rocks in the Hungarian part of the Pannonian Basin. Thermal water production in Hungary increased significantly from the early 1970s. Regional-scale exploitation of geothermal reservoirs without re-injection resulted in basin-scale pressure drop in the Upper Pannonian (Upper Miocene) sediments, leading to compaction. This compaction resulted in ground subsidence primarily through poro-elastic coupling. We investigated surface deformation at the Szentes geothermal filed, SE Hungary, where the largest pressure decline occurred. Subsequently, hydraulic head recovery in the western part of the geothermal reservoir was initiated in the mid-1990s. We obtained data from the European Space Agency’s Envisat satellites to estimate the ground motions for the period of November 2002–December 2006. We applied inverse geomechanical modeling to estimate reservoir properties and processes. We constrained the model parameters using the Ensemble Smoother with Multiple Data Assimilation, which allowed us to incorporate large amounts of surface movement observations in a computationally efficient way. Ground movements together with the modeling results show that uplift of the Szentes geothermal field occurred during the observation period. Since no injection wells were operated at Szentes before 2018, and production temperatures remained relatively constant through the entire production period, we explain ground uplift with pore pressure increase due to natural recharge. The estimated decompaction coefficients of the reservoir system characterizing the elastic behavior of the Szentes geothermal reservoir varies between ~ 0.2 × 10–9 and 2 × 10–9 Pa−1. Compaction coefficients of the reservoir system corresponding to the earlier depressurization period, from ~ 1970 to the mid-1990s, may be significantly larger due to the potential inelastic behavior and permanent compaction of clay-rich aquitards. The improved parametrization enables better forecasting of the reservoir behavior and facilitates the assessment of future subsidence scenarios that are helpful for the establishment of a sustainable production scheme

    Interevent-time distribution and aftershock frequency in non-stationary induced seismicity

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    The initial footprint of an earthquake can be extended considerably by triggering of clustered aftershocks. Such earthquake–earthquake interactions have been studied extensively for data-rich, stationary natural seismicity. Induced seismicity, however, is intrinsically inhomogeneous in time and space and may have a limited catalog of events; this may hamper the distinction between human-induced background events and triggered aftershocks. Here we introduce a novel Gamma Accelerated-Failure-Time model for efficiently analyzing interevent-time distributions in such cases. It addresses the spatiotemporal variation and quantifies, per event, the probability of each event to have been triggered. Distentangling the obscuring aftershocks from the background events is a crucial step to better understand the causal relationship between operational parameters and non-stationary induced seismicity. Applied to the Groningen gas field in the North of the Netherlands, our model elucidates geological and operational drivers of seismicity and has been used to test for aftershock triggering. We find that the hazard rate in Groningen is indeed enhanced after each event and conclude that aftershock triggering cannot be ignored. In particular we find that the non-stationary interevent-time distribution is well described by our Gamma model. This model suggests that 27.0(± 8.5)% of the recorded events in the Groningen field can be attributed to triggering

    Depletion-Induced Seismicity at the Groningen Gas Field: Coulomb Rate-and-State Models Including Differential Compaction Effect

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    We implement a Coulomb rate‐and‐state approach to explore the nonlinear relation between stressing rate and seismicity rate in the Groningen gas field. Coulomb stress rates are calculated, taking into account the 3‐D structural complexity of the field and including the poroelastic effect of the differential compaction due to fault offsets. The spatiotemporal evolution of the Groningen seismicity must be attributed to a combination of both (i) spatial variability in the induced stressing rate history and (ii) spatial heterogeneities in the rate‐and‐state model parameters. Focusing on two subareas of the Groningen field where the observed event rates are very contrasted even though the modeled seismicity rates are of similar magnitudes, we show that the rate‐and‐state model parameters are spatially heterogeneous. For these two subareas, the very low background seismicity rate of the Groningen gas field can explain the long delay in the seismicity response relative to the onset of reservoir depletion. The characteristic periods of stress perturbations, due to gas production fluctuations, are much shorter than the inferred intrinsic time delay of the earthquake nucleation process. In this regime the modeled seismicity rate is in phase with the stress changes. However, since the start of production and for two subareas of our analysis, the Groningen fault system is unsteady and it is gradually becoming more sensitive to the stressing rate

    Depletion‐Induced Seismicity at the Groningen Gas Field: Coulomb Rate‐and‐State Models Including Differential Compaction Effect

    No full text
    International audienceWe implement a Coulomb rate‐and‐state approach to explore the nonlinear relation between stressing rate and seismicity rate in the Groningen gas field. Coulomb stress rates are calculated, taking into account the 3‐D structural complexity of the field and including the poroelastic effect of the differential compaction due to fault offsets. The spatiotemporal evolution of the Groningen seismicity must be attributed to a combination of both (i) spatial variability in the induced stressing rate history and (ii) spatial heterogeneities in the rate‐and‐state model parameters. Focusing on two subareas of the Groningen field where the observed event rates are very contrasted even though the modeled seismicity rates are of similar magnitudes, we show that the rate‐and‐state model parameters are spatially heterogeneous. For these two subareas, the very low background seismicity rate of the Groningen gas field can explain the long delay in the seismicity response relative to the onset of reservoir depletion. The characteristic periods of stress perturbations, due to gas production fluctuations, are much shorter than the inferred intrinsic time delay of the earthquake nucleation process. In this regime the modeled seismicity rate is in phase with the stress changes. However, since the start of production and for two subareas of our analysis, the Groningen fault system is unsteady and it is gradually becoming more sensitive to the stressing rate
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