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Background: The Covid-19 pandemic caused a shutdown of healthcare systems in many countries. We explored the impact on hypertension care in the Excellence Center (EC) network of the European Society of Hypertension. Methods: We conducted a 17-question electronic survey among ECs. Results: Overall, 52 ECs from 20 European and three non-European countries participated, providing hypertension service for a median of 1500 hypertensive patients per center per year. Eighty-five percent of the ECs reported a shutdown lasting for 9 weeks (range 0–16). The number of patients treated per week decreased by 90%: from a median of 50 (range 10–400) before the pandemic to a median of 5.0 (range 0–150) during the pandemic (P < 0.0001). 60% of patients (range 0–100%) declared limited access to medical consultations. The majority of ECs (57%) could not provide 24-h ambulatory BP monitoring, whereas a median of 63% (range 0–100%) of the patients were regularly performing home BP monitoring. In the majority (75%) of the ECs, hypertension service returned to normal after the first wave of the pandemic. In 66% of the ECs, the physicians received many questions regarding the use of renin–angiotensin system (RAS) blockers. Stopping RAS-blocker therapy (in a few patients) either by patients or physicians was reported in 27 and 36.5% of the ECs. Conclusion: Patient care in hypertension ECs was compromised during the Covid-19-related shutdown. These data highlight the necessity to develop new strategies for hypertension care including virtual clinics to maintain services during challenging times.

Linear, fully gyrokinetic, full radius (global), large aspect ratio studies of Alfven-ion temperature gradient mode (AITG) or kinetic ballooning modes or beta-induced Alfven eigenmodes considering only "passing" species is presented. Effects hitherto completely neglected in a full radius approach such as B-parallel to-fluctuations and the ones which have been treated partly [Phys. Plasmas 10, 1424 (2003)] such as Shafranov shifts are included. To this end, an existing code EM-GLOGYSTO has been upgraded to incorporate these effects. Among others, the most interesting results include: (i) For relatively large positive magnetic shear (s) over cap [1.25

Electromagnetic microinstabilities in tokamak plasmas are studied by means of a linear global eigenvalue numerical code. Ion dynamics is described by the gyrokinetic equation, so that finite ion Larmor radius effects are taken into account to all orders. Nonadiabatic electrons are included in the model, with passing particles described by the drift-kinetic equation and trapped particles through the bounce averaged drift-kinetic equation. A large aspect ratio plasma with circular shifted surfaces is considered for the numerical implementation. The effects of an electromagnetic perturbation on toroidal ion temperature gradient driven modes are studied, confirming the stabilization of these modes with increasing beta (parameter identifying the ratio of the plasma pressure to the magnetic pressure). The threshold for the destabilization of an electromagnetic mode, the so-called kinetic ballooning mode or Alfvenic ion temperature gradient mode is identified. Moreover, owing to the global formulation, the radial structure of these electromagnetic modes is observed for the first time. Finally, the contributions of trapped electron dynamics and the effects of the Shafranov shift are addressed. (C) 2003 American Institute of Physics.

Global gyrokinetic particle simulations have been used to search tokamak configurations which are stable again st the ion-temperature-gradient - driven (ITG) modes commonly held responsible for the core anomalous ion heat transport. The stable configurations are-characterized by strongly reduced or reversed del B drifts on the low-field side. Since excellent transport properties have been observed in high beta p (poloidal beta) tokamak experiments, we conjecture, as a result of our simulations, that this may be due to the stabilization of ITG modes by the reduction of the del B drifts.

A new code, SEMAL, has been developed which solves the linearized Vlasov-Maxwell wave equations to all orders in Larmor radii. Arbitrary density and temperature profiles as well as non-uniform magnetic fields are considered in slab geometry. The vacuum regions adjacent to the plasma slab are limited by perfectly conducting walls and contain an antenna as an excitation source. The linear response is obtained by solving the system of one first-order and two second-order integro-differential equations using a non-polluting finite element discretization. The general equations in the Fourier space, derived in a new comprehensive way, and their inverse transform, using k(y) = 0, are described as well as the convergence and non-polluting properties of the method. We present the results concerning the influence of alpha particles on ICRF heating schemes for ITER, where we show that small alphas concentration can alter the steady-state operation envisaged with ICRF fast wave current-drive.