Frame Theory for Signal Processing in Psychoacoustics

This review chapter aims to strengthen the link between frame theory and signal processing tasks in psychoacoustics. On the one side, the basic concepts of frame theory are presented and some proofs are provided to explain those concepts in some detail. The goal is to reveal to hearing scientists how this mathematical theory could be relevant for their research. In particular, we focus on frame theory in a filter bank approach, which is probably the most relevant view-point for audio signal processing. On the other side, basic psychoacoustic concepts are presented to stimulate mathematicians to apply their knowledge in this field

Effect of COVID-19 lockdown on maternity care and maternal outcome in the Netherlands: a national quasi-experimental study

Objectives: The COVID-19 pandemic and associated lockdowns disrupted health care worldwide. High-income countries observed a decrease in preterm births during lockdowns, but maternal pregnancy–related outcomes were also likely affected. This study investigates the effect of the first COVID-19 lockdown (March–June 2020) on provision of maternity care and maternal pregnancy–related outcomes in the Netherlands. Study design: National quasi-experimental study. Methods: Multiple linked national registries were used, and all births from a gestational age of 24+0 weeks in 2010–2020 were included. In births starting in midwife-led primary care, we assessed the effect of lockdown on provision of care. In the general pregnant population, the impact on characteristics of labour and maternal morbidity was assessed. A difference-in-regression-discontinuity design was used to derive causal estimates for the year 2020. Results: A total of 1,039,728 births were included. During the lockdown, births to women who started labour in midwife-led primary care (49%) more often ended at home (27% pre-lockdown, +10% [95% confidence interval: +7%, +13%]). A small decrease was seen in referrals towards obstetrician-led care during labour (46%, −3% [−5%,−0%]). In the overall group, no significant change was seen in induction of labour (27%, +1% [−1%, +3%]). We found no significant changes in the incidence of emergency caesarean section (9%, −1% [−2%, +0%]), obstetric anal sphincter injury (2%, +0% [−0%, +1%]), episiotomy (21%, −0% [−2%, +1%]), or post-partum haemorrhage: >1000 ml (6%, −0% [−1%, +1%]). Conclusions: During the first COVID-19 lockdown in the Netherlands, a substantial increase in homebirths was seen. There was no evidence for changed available maternal outcomes, suggesting that a maternity care system with a strong midwife-led primary care system may flexibly and safely adapt to external disruptions

The association between parity and spontaneous preterm birth:A population based study

The authors thank the Dutch midwives, obstetricians, neonatologists, and other perinatal health care providers for the registration of perinatal information and the foundation of the Netherlands Perinatal Registry (www.perined.nl) for permission to use the registry data (approval no. 17.34).Peer reviewedPublisher PD

The effectiveness of multifetal pregnancy reduction in trichorionic triplet gestation

Item does not contain fulltextOBJECTIVE: The objective of the study was to assess in trichorionic triplet pregnancies the effectiveness of elective reduction to twins. STUDY DESIGN: This was a nationwide retrospective cohort study. We compared the time to delivery and perinatal mortality in trichorionic triplet pregnancies electively reduced to twins with ongoing trichorionic triplets and primary dichorionic twins. RESULTS: We identified 86 women with reduced trichorionic triplet pregnancies, 44 with ongoing trichorionic triplets, and 824 with primary twins. Reduced triplets had a median gestational age at delivery of 36.1 weeks (interquartile range [IQR], 33.3-37.5 weeks) vs 33.3 (IQR, 28.1-35.2) weeks for ongoing triplets and 37.1 (IQR, 35.3-38.1) weeks for primary twins (P < .001). The total number of surviving children in the reduced group was 155 (90%) vs 114 (86%) in the ongoing triplet group. After reduction, 75 of women (87%) had all their fetuses surviving, compared with 36 (82%) (relative risk [RR], 1.3; 95% confidence interval [CI], 0.72-2.3) for ongoing triplets and 770 (93%) (RR, 0.91; 95% CI, 0.82-1) for primary twins. There were 6 women without any surviving children (7%) after reduction vs 5 (11.4%) (RR, 0.81; 95% CI, 0.47-1.4) among women with ongoing triplets and 32 (3.9%) (RR, 1.7; 95% CI, 0.8-3.7) in women with primary twins. CONCLUSION: In women with a triplet pregnancy, fetal reduction increases gestational age at birth with 3 weeks as compared with ongoing triplets. However, there the impact on neonatal survival is limited

Effect of parental and ART treatment characteristics on perinatal outcomes

STUDY QUESTION: Do parental characteristics and treatment with ART affect perinatal outcomes in singleton pregnancies? SUMMARY ANSWER: Both parental and ART treatment characteristics affect perinatal outcomes in singleton pregnancies. WHAT IS KNOWN ALREADY: Previous studies have shown that singleton pregnancies resulting from ART are at risk of preterm birth. ART children are lighter at birth after correction for duration of gestation and at increased risk of congenital abnormalities compared to naturally conceived children. This association is confounded by parental characteristics that are also known to affect perinatal outcomes. It is unclear to which extent parental and ART treatment characteristics independently affect perinatal outcomes. STUDY DESIGN, SIZE, DURATION: All IVF clinics in the Netherlands (n = 13) were requested to provide data on all ART treatment cycles (IVF, ICSI and frozen-thawed embryo transfers (FET)), performed between 1 January 2000, and 1 January 2011, which resulted in a pregnancy. Using probabilistic data-linkage, these data (n = 36 683) were linked to the Dutch Perinatal Registry (Perined), which includes all children born in the Netherlands in the same time period (n = 2 548 977). PARTICIPANTS/MATERIALS, SETTING, METHODS: Analyses were limited to singleton pregnancies that resulted from IVF, ICSI or FET cycles. Multivariable models for linear and logistic regression were fitted including parental characteristics as well as ART treatment characteristics. Analyses were performed separately for fresh cycles and for fresh and FET cycles combined. We assessed the impact on the following perinatal outcomes: birth weight, preterm birth below 37 or 32 weeks of gestation, congenital malformations and perinatal mortality. MAIN RESULTS AND THE ROLE OF CHANCE: The perinatal outcomes of 31 184 out of the 36 683 ART treatment cycles leading to a pregnancy were retrieved through linkage with the Perined (85% linkage). Of those, 23 671 concerned singleton pregnancies resulting from IVF, ICSI or FET. Birth weight was independently associated with both parental and ART treatment characteristics. Characteristics associated with lower birth weight included maternal hypertensive disease, non-Dutch maternal ethnicity, nulliparity, increasing duration of subfertility, hCG for luteal phase support (compared to progesterone), shorter embryo culture duration, increasing number of oocytes retrieved and fresh embryo transfer. The parental characteristic with the greatest effect size on birth weight was maternal diabetes (adjusted difference 283 g, 95% CI 228-338). FET was the ART treatment characteristic with the greatest effect size on birth weight (adjusted difference 100 g, 95% CI 84-117) compared to fresh embryo transfer. Preterm birth was more common among mothers of South-Asian ethnicity. Preterm birth was less common among multiparous women and women with 'male factor' as treatment indication (compared to 'tubal factor'). LIMITATIONS, REASONS FOR CAUTION: Due to the retrospective nature of our study, we cannot prove causality. Further limitations of our study were the inability to adjust for mothers giving birth more than once in our dataset, missing values for several variables and limited information on parental lifestyle and general health. WIDER IMPLICATIONS OF THE FINDINGS: Multiple parental and ART treatment characteristics affect perinatal outcomes, with birth weight being influenced by the widest range of factors. This highlights the importance of assessing both parental and ART treatment characteristics in studies that focus on the health of ART-offspring, with the purpose of modifying these factors where possible. Our results further support the hypothesis that the embryo is sensitive to its early environment. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by Foreest Medical School, Alkmaar, the Netherlands (grants: FIO 1307 and FIO 1505). B.W.M. reports grants from NHMRC and consultancy for ObsEva, Merck KGaA, iGenomics and Guerbet. F.B. reports research support grants from Merck Serono and personal fees from Merck Serono. A.C. reports travel support from Ferring BV. and Theramex BV. and personal fees from UpToDate (Hyperthecosis), all outside the remit of the current work. The remaining authors report no conflict of interests.N/A

Increasing trends in a low 5-min Apgar score among (near) term singletons: a Dutch nationwide cohort study

Objective: To investigate trends in low Apgar scores in (near) term singletons using the Dutch Perinatal Registry. Methods: In a cohort of 1,583,188 singletons liveborn ≥35 weeks of gestation in the period 2010–2019, we studied trends in low 5-min Apgar scores (<7 and <4) using Cochrane Armitage trend tests. Results: The proportion of infants with low Apgar scores <7 and <4 increased significantly between 2010–2019 (1.04–1.42% (p < 0.001), 0.17–0.19% (p = 0.009), respectively). Neonatal mortality remained unchanged. Induction of labour, epidural analgesia and planned caesarean section showed an increasing trend. Instrumental vaginal delivery and emergency caesarean section were performed less frequently over time, but these intervention subgroups showed the highest relative increase in infants with low Apgar scores. Conclusions: In the Netherlands, the risk of a low 5-min Apgar score increased over the last decade. The highest relative increase was observed in subgroups of instrumental vaginal delivery and emergency caesarean section