Search

Introduction Fertility problems may have a devastating impact on the people involved. Specifically, in highly pronatalist settings like Ghana, the personal and social consequences are high. This study focused on the relationship between stigmatisation because of fertility problems and quality of life among Ghanaian women and men, and the possible mediating role of coping strategies. Methods Participants (38 women, 11 men) were recruited with the help of a patient organisation and a hospital in Accra. Standardised instruments were used to measure the stigmatisation of having fertility problems, fertility quality of life and coping with fertility problems. Partial Pearson r correlations were conducted, followed by bootstrapped mediation analyses (PROCESS macro). Results Stigmatisation was negatively correlated with fertility quality of life, and fertility quality of life was negatively correlated with active-avoidance coping. Active avoidance coping partially mediated the relationship between being stigmatised because of fertility problems and fertility quality of life. Conclusions Professionals working with people with fertility problems should pay more attention to how people are coping with experiences of stigmatisation.

Speed range maximization of a traction drive is one of the main focus points in transportation electrification research. This paper presents a range improvement method, suitable for each type of open-winding three-phase electric machine. A dual-inverter drive system is proposed, which is capable of enhancing the phase voltages applied to the open-winding electrical machine. A common-mode current at the third-harmonic of the intended output frequency is deliberately generated to boost the supply voltage of one inverter, thereby extending the operating range of the machine above the base angular velocity. The need for a reactive fundamental frequency current to weaken the machine field is avoided as a result. A method is introduced for simultaneously optimizing the inverter voltages and minimizing the required boost current, thereby maximizing the speed range and the overall efficiency. The analysis is explained and verified by experiments. A relative angular velocity advancement of a factor 1.6 is achieved using voltage range enhancement.

Design of TES microcalorimeters requires a tradeoff between resolution and dynamic range. Often, experimenters will require linearity for the highest energy signals, which requires additional heat capacity be added to the detector. This results in a reduction of low energy resolution in the detector. We derive and demonstrate an algorithm that allows operation far into the nonlinear regime with little loss in spectral resolution. We use a least squares optimal filter that varies with photon energy to accommodate the nonlinearity of the detector and the non-stationarity of the noise. The fitting process we use can be seen as an application of differential geometry. This recognition provides a set of well-developed tools to extend our work to more complex situations. The proper calibration of a nonlinear microcalorimeter requires a source with densely spaced narrow lines. A pulsed laser multi-photon source is used here, and is seen to be a powerful tool for allowing us to develop practical systems with significant detector nonlinearity. The combination of our analysis techniques and the multi-photon laser source create a powerful tool for increasing the performance of future TES microcalorimeters.

Some sort of infertility treatments, including the use of advanced reproductive technologies (ARTs), is nowadays provided at several places in sub-Saharan Africa. Yet, to date only a few studies have actually looked into the way these treatments are offered, used and experienced. In this review article the authors present and discuss empirical study findings that give insight into the way biomedical infertility care is provided, considered, experienced and/or used in sub-Saharan African countries. They concentrate on four themes that were often referred to in the reviewed studies and underline the importance of taking into account the local sociocultural context and notions when developing and implementing infertility care, namely: counselling, male involvement, acceptability of ARTs and the use of donor material (semen and embryos). In the conclusion the authors emphasize the importance of preventing infertility as part of integrated reproductive health programs and the need to improve the quality of (low tech) infertility care in the public health sector by means of standardized guidelines, training of health staff and improved counselling. In addition, from a reproductive rights perspective, they support initiatives to introduce low cost ARTs to treat tubal factor related infertility. They also point to potential unintended side effects of the introduction of ARTs and the use of donor material in the sub-Saharan African context, affecting gender inequity and inequity between citizens from different social classes, and argue that such effects should be acknowledged and avoided by all possible means. Finally, they present an agenda for future social science research on this topic in sub-Saharan Africa.

Field weakening operation of an electrical machine is a conventional method to extend the angular velocity range of a system above the peak output voltage of the inverter. A downside, however, is that an increased reactive current is required that creates losses but no output torque. A dual voltage source inverter topology is proposed, capable of driving an electrical machine without weakening its field in an extended speed range. For this purpose, a second inverter fed by a capacitor only is connected to the open-end side of the machine windings. Charging the floating capacitors is realized by adding an AC zero sequence current to the regular machine currents. The operating principles of the presented topology are demonstrated, showing their possible advantages when driving an electrical machine. Simulation results confirm the proposed ideas.