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Background. To improve maternal health, studies of maternal morbidity are increasingly being used to evaluate the quality of maternity care, in addition to studies of mortality. While South Africa (SA) has a well-established confidential enquiry into maternal deaths, there is currently no structure in place to systematically collect and analyse maternal near-misses (MNMs) at national level.Objectives. To synthesise MNM indicators and causes in SA by performing a systematic literature search, and to investigate perceived needs for data collection related to MNMs and determine whether the MNM tool from the World Health Organization (WHO-MNM) would require adaptations in order to be implemented.Methods. The study used a mixed-methods approach. A systematic literature search was conducted to find all published data on MNM audits in SA. Semi-structured interviews were conducted virtually with maternal health experts throughout the country who had been involved in studies of MNMs, and main themes arising in the interviews were synthesised. A method for MNM data collection for SA use was discussed with these experts.Results. The literature search yielded 797 articles, 15 of which met the WHO-MNM or Mantel et al. severe acute maternal morbidity criteria. The median (interquartile range) MNM incidence ratio in SA was 8.4/1 000 (5.6 - 8.7) live births, the median maternal mortality ratio was 130/100 000 (71.4 - 226) live births, and the median mortality index was 16.6% (11.7 - 18.8). The main causes of MNMs were hypertensive disorders of pregnancy and obstetric haemorrhage. Eight maternal health experts were interviewed from May 2020 to February 2021. All participants focused on the challenges of implementing a national MNM audit, yet noted the urgent need for one. Recognition of MNMs as an indicator of quality of maternity care was considered to lead to improved management earlier in the chain of events, thereby possibly preventing mortality. Obtaining qualitative information from women with MNMs was perceived as an important opportunity to improve the maternity care system. Participants suggested that the WHO-MNM tool would have to be adapted into a simplified tool with more clearly defined criteria and a number of specific diagnoses relevant to the SA setting. This ‘Maternal near-miss: Inclusion criteria and data collection form’ is provided as a supplementary file.Conclusion. Adding MNMs to the existing confidential maternal death enquiry could potentially contribute to a more robust audit with data that may inform health systems planning. This was perceived by SA experts to be valuable, but would require context-specific adaptations to the WHO-MNM tool. The available body of evidence is sufficient to justify moving to implementation.

The KIT’s 3D Ultrasound Computer Tomography (USCT) II system has a multistatic setup of 2041 ultrasound transducers with approx. 1.5 MHz 6dB bandwidth and 36◦ 3 dB opening angle for 2.5 MHz. To increase the region of interest for a next USCT generation, the opening angle should be increased to approx. 60◦ and the bandwidth doubled. To increase the opening angle the size of the transducer elements was decreased to approximately half the size. A circular aperture was chosen for homogenicity of the radiation pattern in 3D. The transducer design utilizes piezo-fibres by the established Fraunhofer IMT piezo-fibre composite technology. The fibres were fabricated from PZT powder using the polysulfone spinning process. 17 fibres were positioned with a mechanical mask and filled with a matrix of epoxy. From this rod piezo composite discs were sawed and polarized. Electrodes were generated by silver-filled epoxy adhesive on the top and bottom side. Materials for acoustic backing is a Tungsten-Polyurethane composite and for acoustic matching ia aluminium oxide composite material (TMM4). Ultrasound characteristics were evaluated quantitatively with a Onda HNC-400 hydrophone in a 3-axis water tank for a randomly selected sample transducer (see Fig. a.)). Characteristics evaluated were the pressure field as function over frequency and angle in the far-field (see Fig. b.)), following the use-case. For excitation a linear encoded chirp was used, for SNR improvements averaging of measurements (64 to 256 times) was conducted. The analysis compensated for the hydrophon’s frequency and angular damping characteristics. The presented results show that the desired characteristics were mostly achieved: the 6 dB bandwidth could be vastly improved by roughly 200% (see Fig. d.)). The 6 dB pressure opening angle was approx. 50◦ (see Fig. c.)), not completly fullfilling the simulated expectations, an improvement by 31% was achieved. The results are promising for the next 3D USCT III generation.

During sleep, the time-compressed replay of engrams acquired during preceding wakefulness drives memory consolidation. We demonstrate in healthy humans that direct electrical coupling between neurons via gap junctions, i.e., electrical synapses, contributes to this beneficial effect of sleep. Twenty male participants learned a declarative word-pair task and a procedural finger sequence tapping task before receiving the antimalarial mefloquine that is known to block electrical synapses. Retrieval was tested after a retention interval of approximately 20.5 hours that included nocturnal sleep. As predicted, mefloquine given before sleep impaired the retention of declarative memory. In contrast, this effect was absent in control groups, which stayed awake or received mefloquine after sleep. Irrespective of sleep or administration time, mefloquine enhanced retention performance on the procedural memory control task. We conclude that sleep-dependent processes relying on electrical neuronal coupling enable hippocampus-dependent declarative memory consolidation, presumably via time-compressed hippocampal replay of memory traces within sharp-wave/ripple complexes. The recruitment of this understudied form of neuronal information transfer may be necessary to achieve fast-paced memory reprocessing during sleep. Considering that drugs targeting neurochemical synapses have recently fallen short of substantially advancing the treatment of memory impairments in Alzheimer’s disease, schizophrenia or during normal aging, unraveling the contribution of gap junctions to sleep-dependent declarative memory formation can be expected to open new therapeutic avenues.

The vertical distribution of dissolved hydroxylamine (NH2OH) was measured for the first time at 10 stations in the western, southern and central Baltic Sea during a cruise in February 2004. The distribution of dissolved NH2OH was complex due to the interplay of in-situ production in the shallow western and southern Baltic Sea and the hydrographical setting in the central Baltic Sea caused by the major North Sea water inflow event in January 2003. We conclude that nitrification might be the major source of NH2OH, whereas anaerobic ammonium oxidation (anammox) appeared to be negligible. We suggest that a "fresh" nitrifying system, in which the NH+4-oxidation rates exceeded the NO−2-oxidation rates, favoured the build-up of NH2OH.

At the Karlsruhe Institue of Technology (KIT), a 3D-Ultrasound Computer Tomography (3D-USCT) medical imaging system for early breast cancer detection is currently developed. With the next generation of 3D-USCT 2.5, the current region of interest (ROI) of 10 x 10 x 10 cm�� shall be increased to 20 x 20 x 20 cm�� to allow reliable imaging results also for bigger female breasts. Therefore, the opening angle (OA) of the future transducers should be increased to approx. 60 �� at 3 dB while other characteristics such as bandwidth (BW) and resonance frequency should be preserved or even improved. Based on Fraunhofer IKTS Piezofibre composites utilized for transducer production, an optimization is performed on piezoelectric sensor geometry and size, type and structure of matching and backing layer and interconnection technology of the several parts of the transducer

Electrocaloric device structures have been developed as multilayer ceramics (MLCs) based on fundamental research carried out on PMN-8PT bulk ceramics. Two different MLC structures were prepared with nine layers each and layer thicknesses of 86 μm and 39 μm. The influence of the device design on its properties has been characterized by microstructural, dielectric, ferroelectric, and direct electrocaloric measurement. For direct characterization two different methods, ie temperature reading (thermistor and thermocouple) and heat flow measurement (differential scanning calorimetry), were used. A comparison of results revealed a highly satisfactory agreement between the different methods. This study confirms that MLCs are promising candidates for implementation into energy-efficient electrocaloric cooling systems providing large refrigerant volume and high electrocaloric effect. Due to their micron-sized active layers, they allow for the application of high electric fields under low operation voltages. We measured a maximum electrocaloric temperature change of ΔT = 2.67 K under application/withdrawal of an electric field of ΔE = 16 kV mm⁻¹, which corresponds to operation voltages below 1.5 kV.