Klimaatdijk een verkenning

IntroductionClimate change, land subsidence and the increasing economic value of property and activities in flood-prone areas justify the question of how we can maintain flood protection in the Netherlands at its current level, or even improve it. The changing social, scientific and technical developments and insights of our day mean that the time is ripe to consider alternatives for flood protection, other than the customary call to raise the dikes yet higher, time and again.The Climate DikeThe Climate Dike is a logical addition to the current practice of raising and reinforcing dikes. A Climate Dike is defined here as ¿a collective term for design components that result in flood defences so robust that they are virtually impossible to breach, and thus offer lasting protection, even in the face of ongoing climate change The Climate Dike concerns a type of dike that allows some wave overflow and even a limited amount of flooding, but which prevents the uncontrolled catastrophic dike breaks associated with devastating flooding of the hinterland. The number of potential victims and the resulting damage are therefore in no way comparable to those incurred when a traditional dike breaks. The risk, calculated as a product of the probability of occurrence and the resulting damage, is therefore drastically reduced.Another feature of the Climate Dike is its integrated multi-functional character. On it, a wider range of socio-economic interests can be built than on traditional dikes. This means that greater opportunities for financing also become available.Before the Climate Dike can be approached as a serious alternative, clarity is needed on the relevant information, experience, policy and knowledge that exists (and does not yet exist). The current inventory was conducted with that requirement in mind.The authors looked at, among others, projects that presented problems and challenges similar to those expected in development of a Climate Dike. These relate, among others, to technical,economic, social and spatial issues.A long time horizonBecause of its more multidisciplinary character, development of a Climate Dike requires a longer time horizon than a traditional dike. The current system of 5-yearly testing, in which dikes that fail to meet current safety standards are immediately subjected to an urgent upgrade trajectory, provides an inadequate framework for developing the Climate Dike.In the current system, evolving scientific insights, environmental conditions and safety requirements could mean that even immediately after a dike has been strengthened, the next reinforcement is just around the corner. Such a situation is clearly undesired for a multifunctional Climate Dike with, for example, buildings on it. Also, after its construction, a Climate Dike has to be able to guarantee safety for many more decades than a traditional dike, and to do so in a way that other interests can build on, literally and figuratively. A longer planning horizon and new means of anticipating on future developments are therefore essential.ChallengingThe Climate Dike has no set dimensions or form, though it does tend to be wider and less steep than traditional dikes and include a protection zone parallel to existing flood defences. It goes without saying that not every aspect of the Climate Dike concept, which is often broad in both functional and physical terms, will be applicable at every location.One of the many challenges arising in applying the Climate Dike concept is the question of how to effectively look ahead over an extremely long stretch of time (for example, a century), since we cannot predict with any certainty how society will look after such a long period. How can ideas and procedures be tailored to as yet unknown future developments? How can we best ensure the ability to adapt to new situations and insights?One of the complexities involved in developing a Climate Dike is the use of space. How can the required space be secured without having to demolish large numbers of buildings and infrastructure and without excluding large zones of land from any possible socio-economic activity, perhaps for many decades?Costs and benefitsA Climate Dike is costly, if one limits the field of vision to the safety aspect and the traditional time horizon of 50 years. Broaden the view to bring in multiple interests that over a longer time period can, literally and figuratively, build on the presence of the Climate Dike, then this form of flood protection becomes much more financially attractive. Certainly when considering other options for flood protection, such as compartmentalisation dikes or the raising of immense tracts of land.Law and legislationTo give designers and managers of flood defences more opportunity to develop the Climate Dike, modifications are required in current design guidelines and technical prerequisites. Also, it must be made clear whether and how a Climate Dike is to be subjected to the 5-yearly testing cycle. Is such testing needed if the dike is considered to be virtually impossible to breach? How do we deal with the probability of flooding versus the risk of a dike break? Current law and legislation are geared fairly specifically to the traditional dike. Alternative concepts such as the Climate Dike call for modified policies, laws and legislation, as well as newly formulated design requirements and prerequisites. Or it will have to be made clearer how these should be interpreted for such innovative concepts

Phase Measurement for Driven Spin Oscillations in a Storage Ring

This paper reports the first simultaneous measurement of the horizontal and vertical components of the polarization vector in a storage ring under the influence of a radio frequency (rf) solenoid. The experiments were performed at the Cooler Synchrotron COSY in J\"ulich using a vector polarized, bunched $0.97\,\textrm{GeV/c}$ deuteron beam. Using the new spin feedback system, we set the initial phase difference between the solenoid field and the precession of the polarization vector to a predefined value. The feedback system was then switched off, allowing the phase difference to change over time, and the solenoid was switched on to rotate the polarization vector. We observed an oscillation of the vertical polarization component and the phase difference. The oscillations can be described using an analytical model. The results of this experiment also apply to other rf devices with horizontal magnetic fields, such as Wien filters. The precise manipulation of particle spins in storage rings is a prerequisite for measuring the electric dipole moment (EDM) of charged particles

Spin tune mapping as a novel tool to probe the spin dynamics in storage rings

Precision experiments, such as the search for electric dipole moments of charged particles using storage rings, demand for an understanding of the spin dynamics with unprecedented accuracy. The ultimate aim is to measure the electric dipole moments with a sensitivity up to 15 orders in magnitude better than the magnetic dipole moment of the stored particles. This formidable task requires an understanding of the background to the signal of the electric dipole from rotations of the spins in the spurious magnetic fields of a storage ring. One of the observables, especially sensitive to the imperfection magnetic fields in the ring is the angular orientation of stable spin axis. Up to now, the stable spin axis has never been determined experimentally, and in addition, the JEDI collaboration for the first time succeeded to quantify the background signals that stem from false rotations of the magnetic dipole moments in the horizontal and longitudinal imperfection magnetic fields of the storage ring. To this end, we developed a new method based on the spin tune response of a machine to artificially applied longitudinal magnetic fields. This novel technique, called \textit{spin tune mapping}, emerges as a very powerful tool to probe the spin dynamics in storage rings. The technique was experimentally tested in 2014 at the cooler synchrotron COSY, and for the first time, the angular orientation of the stable spin axis at two different locations in the ring has been determined to an unprecedented accuracy of better than $2.8\mu$rad.Comment: 32 pages, 15 figures, 7 table

Phase locking the spin precession in a storage ring

This letter reports the successful use of feedback from a spin polarization measurement to the revolution frequency of a 0.97 GeV/$c$ bunched and polarized deuteron beam in the Cooler Synchrotron (COSY) storage ring in order to control both the precession rate ($\approx 121$ kHz) and the phase of the horizontal polarization component. Real time synchronization with a radio frequency (rf) solenoid made possible the rotation of the polarization out of the horizontal plane, yielding a demonstration of the feedback method to manipulate the polarization. In particular, the rotation rate shows a sinusoidal function of the horizontal polarization phase (relative to the rf solenoid), which was controlled to within a one standard deviation range of $\sigma = 0.21$ rad. The minimum possible adjustment was 3.7 mHz out of a revolution frequency of 753 kHz, which changes the precession rate by 26 mrad/s. Such a capability meets a requirement for the use of storage rings to look for an intrinsic electric dipole moment of charged particles

Diversité des méthodes utilisées par les laboratoires français pour la surveillance des infections à cytomégalovirus humain

Monitoring cytomegalovirus circulating viral load is an important parameter of the follow-up in immunocompromised patients. It can be measured either by DNAemia or by pp65 antigenemia. The French national reference center for cytomegaloviruses organized an investigation of practice in 37 teacher hospital virology laboratories to assess the situation in France in 2010. Methods A questionnaire was sent to collect following information: method used in routine for monitoring of circulating viral load of CMV, assay used, sample matrix and extraction method. Results Thirty-six over thirty-seven laboratories filled the questionnaire. Among these, 67% used the quantitative PCR in routine, 11% antigenemia and 22% antigenemia or quantitative PCR; 87% of the laboratories use whole blood for quantitative PCR, whereas 10% and 3% use plasma and leukocytes respectively. Among the laboratories using DNAemia, 100% used real-time PCR assays, 91% use an automated extraction and 9% a manual extraction. Conclusion Thus in France, measurement of DNAemia by real-time PCR is a tool, which gradually replaces the antigenemia for the monitoring of cytomegalovirus infection among immunocompromised patients. The very great diversity of the methods used justifies the installation of a national quality control on total blood, matrix used by 87% of the laboratories

Week 96 efficacy and safety results of the phase 3, randomized EMERALD trial to evaluate switching from boosted-protease inhibitors plus emtricitabine/tenofovir disoproxil fumarate regimens to the once daily, single-tablet regimen of darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) in treatment-experienced, virologically-suppressed adults living with HIV-1

Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg was investigated through 96 weeks in EMERALD (NCT02269917). Virologically-suppressed, HIV-1-positive treatment-experienced adults (previous non-darunavir virologic failure [VF] allowed) were randomized (2:1) to D/C/F/TAF or boosted protease inhibitor (PI) plus emtricitabine/tenofovir-disoproxil-fumarate (F/TDF) over 48 weeks. At week 52 participants in the boosted PI arm were offered switch to D/C/F/TAF (late-switch, 44 weeks D/C/F/TAF exposure). All participants were followed on D/C/F/TAF until week 96. Efficacy endpoints were percentage cumulative protocol-defined virologic rebound (PDVR; confirmed viral load [VL] >= 50 copies/mL) and VL = 50 copies/mL (VF) (FDA-snapshot analysis). Of 1141 randomized patients, 1080 continued in the extension phase. Few patients had PDVR (D/C/F/TAF: 3.1%, 24/763 cumulative through week 96; late-switch: 2.3%, 8/352 week 52-96). Week 96 virologic suppression was 90.7% (692/763) (D/C/F/TAF) and 93.8% (330/352) (late-switch). VF was 1.2% and 1.7%, respectively. No darunavir, primary PI, tenofovir or emtricitabine resistance-associated mutations were observed post-baseline. No patients discontinued for efficacy-related reasons. Few discontinued due to adverse events (2% D/C/F/TAF arm). Improved renal and bone parameters were maintained in the D/C/F/TAF arm and observed in the late-switch arm, with small increases in total cholesterol/high-density-lipoprotein-cholesterol ratio. A study limitation was the lack of a control arm in the week 96 analysis. Through 96 weeks, D/C/F/TAF resulted in low PDVR rates, high virologic suppression rates, very few VFs, and no resistance development. Late-switch results were consistent with D/C/F/TAF week 48 results. EMERALD week 96 results confirm the efficacy, high genetic barrier to resistance and safety benefits of D/C/F/TAF

Webcams as windows to the mind?: Adirect comparison between in-lab and web-based eye-tracking methods

There is a growing interest in the use of webcams to conduct eye-tracking experiments over the internet. We assessed the performance of two webcam-based eye-tracking techniques for behavioral research: manual annotation of webcam videos (manual eye-tracking) and theautomated WebGazer eye-tracking algorithm. We compared these methods to a traditionalinfrared eye-tracker and assessed their performance in both lab and web-based settings. Inboth lab and web experiments, participants completed the same battery of five tasks, selectedto trigger effects of various sizes: two visual fixation tasks and three visual world tasks testingreal-time (psycholinguistic) processing effects. In the lab experiment, we simultaneously collected infrared eye-tracking, manual eye-tracking, and WebGazer data; in the web experiment, we simultaneously collected manual eye-tracking and WebGazer data. We found that the two webcam-based methods are suited to capture different types of eye-movement patterns. Manual eye-tracking, similar to infrared eye-tracking, detected both large and small effects. WebGazer, however, showed less accuracy in detecting short, subtle effects. There was no notable effect of setting for either method. We discuss the trade-offs researchers face when choosing eye-tracking methods and offer advice for conducting eye-tracking experiments over the internet