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With the launch of the Gravity field and Ocean Circulation Explorer (GOCE) in 2009 the science in gravity got another boost. After the time-lapse and long-wavelength studies from Gravity Recovery and Climate Experiment (GRACE) a new sensor was available for determination of the Earth's gravity field and geoid with high accuracy and spatial resolution. Equipped with a 6-component gradiometer and flying at an altitude of 260 km and less GOCE provides the most detailed measurements of Earth's gravity from space ever. On top, GOCE also provides gravity gradients, i.e., the three-dimensional second derivatives of the gravitational potential. This paper provides a review of the results presented at the ‘GOCE solid Earth workshop’ at the University of Twente, The Netherlands (2012), where an overview was given of the present status of the data models, and applications with GOCE which form the basis for this special issue and the review in this paper. An introduction will be given to the GOCE satellite followed by an overview of GOCE data and gravity models. The present state of GOCE related research in geodesy, oceanography and solid Earth sciences indicates the first steps taken to integrate GOCE in the different application fields. For all three fields an overview is given on the most recent scientific results and developments, and first results specifically focusing on these studies where GOCE data has made a unique contribution and provides insights that would not have been possible without GOCE. [ABSTRACT FROM AUTHOR]

Background: In order to make full use of the opportunities while responsibly managing the risks of working with manufactured nanomaterials (MNM), we need to gain insight into the potential level of exposure to MNM in the industry. Therefore, the goal of this study was to obtain an overview of the potential MNM exposure scenarios within relevant industrial sectors, applied exposure controls, and number of workers potentially exposed to MNM in Dutch industrial sectors producing and applying MNM-enabled end products in the Netherlands. Methods: A survey was conducted in three phases: (i) identification of MNM-enabled end products; (ii) identification of relevant industrial sectors; and (iii) a tiered telephone survey to estimate actual use of the products among 40 sector organizations/knowledge centres (Tier 1), 350 randomly selected companies (Tier 2), and 110 actively searched companies (Tier 3). Results: The most dominant industrial sectors producing or applying MNM-enabled end products (market penetration >5%) are shoe repair shops, automotive, construction, paint, metal, and textile cleaning industry. In the majority of the companies (76%), potential risks related to working with MNM are not a specific point of interest. The total number of workers potentially exposed to MNM during the production or application of MNM-enabled end products was estimated at approximately 3000 workers in the Netherlands. The results of this study will serve as a basis for in-depth exposure and health surveys that are currently planned in the Netherlands. In addition, the results can be used to identify the most relevant sectors for policy makers and future studies focussing on evaluating the risks of occupational exposure to MNM. [ABSTRACT FROM AUTHOR]

Purpose: All forms of past and current high-dose-rate brachytherapy utilize immobile applicators during treatment delivery. The only moving part is the source itself. This paradigm misses an important degree of freedom that, if explored, can in some instances produce previously unachievable dose conformality; that is, the dynamic motion of the applicator itself during treatment delivery. Monte Carlo and treatment planning simulations were used to illustrate the potential benefits of moving applicators for rectal cancer applications in particular. This concept is termed dynamic modulated brachytherapy (DMBT). Methods: The DMBT system uses a high-density, 18.0 g/cm3, 45 mm long tungsten alloy shield, cylindrical in shape, with a small window on one side to encapsulate a 192Ir source, to create collimation that results in a highly directional beam profile. This shield can be dynamically translated and rotated, using an attached robotic arm, during treatment to create a volumetric modulated arc therapy-type delivery, but from inside the rectal cavity. Monte Carlo simulations and planning optimization algorithms were developed inhouse to evaluate the effectiveness of this new approach using 36 clinical treatment plans comprised of 13 patients each treated using the intracavitary mold applicator (ICMA, Nucletron, The Netherlands) to quantify the potential clinical benefit. The prescription dose was 10 Gy/fx and the group had an average clinical target volume of 9.0 ± 3.5 cm3. Ideal phantom geometries were used to evaluate the impact of various shield dimensions and designs on the resulting plan quality. Results: Simulations of ideal phantom geometries found that shields as small as 10 mm in diameter can produce high quality plans. For the clinical patient cases, compared to the ICMA, for equal prescription tumor coverage, the DMBT plans provided >30% decrease in D5 (high dose volume) resulting in a ∼40% decrease in dose heterogeneity index. In addition, mean dose and D98 showed a reduction (typically 40%-60%) on all critical structures evaluated. However, for a 10 Gy prescribed dose there was an increase in total treatment time on average from 7.6 to 20.8 min for a source with an air-kerma strength of 40.25 kU (10 Ci). Conclusions: Dosimetric properties of a novel DMBT system have been described and evaluated. Comparison with the ICMA commercial applicator has shown it to be a prospective step forward in high-dose-rate brachytherapy 192Ir technology. Dynamic motion of an applicator during treatment, for any applicator and site in general, can provide additional degrees of freedom that, if properly considered, can potentially increase the plan quality significantly. [ABSTRACT FROM AUTHOR]