Approche multifactorielle et typologique du concept de fragilité chez les patients hypertendus non contrôlés. Enquête Eclat

Objective The aim of the Eclat survey was to evaluate the frequency of frailty in uncontrolled hypertensives and to individualize different frailty profiles. Patients and methods This was an observational, prospective, longitudinal survey conducted in the cohort of uncontrolled hypertensive patients aged 55 years or more. Morbid events having occurred between two visits at a 6-month interval were reported. Patients with at least one event were considered to be frail. Predictive factors of at least one event were identified (logistic regression). The analysis was completed by a typological analysis (principal components analysis and clustering). Results At least one event occurred in 211 (9%) of 2306 patients (males 55%, 67 ± 9 years old, blood pressure [BP] = 160 ± 11/93 ± 8 mmHg, diabetes 23%): cardiovascular (1.7%), gerontological (5.5%), onset of diabetes (1.3%), worsening of renal impact (2%). Three frailty profiles were identified: patients at low risk (n = 1507, event rate = 6%), with neither cardiovascular risk factors nor target organ damage; patients at moderate risk (n = 335, event rate = 12%) with numerous risk factors but no target organ damage and patients at high risk (n = 243, event rate = 23%), the older ones, in bad general condition, with target organ damage, sensorial deficits and cognitive disorders. In a population of uncontrolled hypertensives aged 55 years or more, 9% could be considered as frailty. Conclusion Therapeutic measures might be adapted according to the frailty profile of the patient. With respect to treatment management, healthcare behaviour could differ depending on these frailty profiles

Unsteady behavior of wall-detached flow inside a steam turbine control valve

Wall-detached flow inside an ultra-supercritical steam turbine control valve was comprehensively investigated with detached-eddy simulation, proper orthogonal decomposition (POD), and flow reconstruction. The dependency of the wall-detached flow on the control valve’s opening ratio and pressure ratio was established first. Scattered wall-detached-flow, merged wall-detached-flow, and intersected wall-detached-flow were then identified by distinguishing the detachment scale of the wall-detached jet. Subsequently, flow analysis was conducted in terms of the statistical flow quantities, i.e., velocity fluctuation, turbulent kinetic energy, pressure loss, and pressure fluctuation. The statistical results demonstrated that the merged wall-detached-flow facilitated the most intensive velocity and pressure fluctuations inside the steam turbine control valve. The intersected wall-detached-flow encountered significant shock-wave reflections along the downstream pipe. By conducting POD analysis and flow reconstruction on the instantaneous flow snapshots, the dominant vortex structures and energetic pressure fluctuation modes were extracted to illustrate the wall-detached flow’s unsteady behavior. The results showed that the instabilities of the scattered wall-detached-flow were primarily represented by the horizontal flapping motion of the wall-detached jet. However, for the merged wall-detached-flow, both the vertical out-phase oscillation and the horizontal flapping motion of the wall-detached jet intensified, yielding essential axial pressure fluctuation modes. As for the intersected wall-detached-flow, due to the complex wave reflections and propagations, essential regions with velocity discontinuities and diagonal crosslines with intensive pressure fluctuations formed inside the valve pipe. These findings are of great practical significance for the operation and optimization of steam turbine control valves in thermal power plants