Active and passive control of flow around a circular cylinder, at transitional Reynolds numbers was investigated experimentally by measuring cylinder surface pressures and wake velocity profiles. Two-and three-dimensional passive boundary layer tripping was considered and periodic active control using piezo-fluidic actuators was introduced from a two-dimensional slot that was nearly tangential to the cylinder surface. The slot location was varied circumferentially by rotating the cylinder and this facilitated either upstream-or downstream-directed actuation using sinusoidal or modulated waveforms. Separation was controlled by two distinct methods, namely: by forcing laminarturbulent transition when applied at relatively small angles (30-60°) from the forward stagnation point; and by directly forcing the separated shear-layer at larger angles. In the latter case, actuation produced the largest load changes when it was introduced at approximately 90°from the forward stagnation point. When the forcing frequency was close to the natural vortex-shedding frequency, the two frequencies "locked-in" creating clear and persistent structures. These were examined and categorized. The "lock-in" effect lowered the base pressure and increased the form-drag whereas delaying separation from the cylinder did the opposite. Nomenclature bslot width C d drag coefficient, d=q 1 D C dp form drag coefficient, dp=q 1 D Flow Turbulence Combust (2007) 78:
<b><i>Objective:</i></b> In 2011, the Israeli Ministry of Health (MOH) published standard guidelines for the follow-up of pregnant women infected by CMV, recommending that amniocentesis be performed in cases of maternal serum viral seroconversion or abnormal sonographic findings suggestive of CMV, in order to prove fetal infection before electing for pregnancy termination. <b><i>Methods:</i></b> A retrospective cohort study was performed, describing 448 pregnant women from 2006 to 2017. We collected data from all women that elected to continue their pregnancies after seroconversion and also of those who chose to undergo pregnancy termination. Subsequently, a telephone survey was then conducted to record outcomes of the newborns of women with CMV seroconversion during pregnancy. <b><i>Results:</i></b> 325 (73%) women chose to continue their pregnancy, while 123 (27%) opted for termination of pregnancy. We found that pregnancy termination due to CMV infection was reduced by 7%, from 72 cases (32%) to 51 cases (25%) after the implementation of the MOH guidelines in 2011. In addition, 182/305 (60%) of women responded to our telephone questionnaire regarding newborn outcomes. Of these women, 45/305 (14%) reported complications, and no correlation was found between the prenatal findings and postnatal outcome among those who have responded to our survey. <b><i>Conclusion:</i></b> Implementation of the new MOH guidelines has reduced the rate of pregnancy termination, without increasing the rate of neonatal complications in Israel with a similar outcome of complication rate as reported in the literature.
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