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BACKGROUND: A range of sacroiliac joint (SIJ) MRI protocols are used in clinical practice but not all were specifically designed for diagnostic ascertainment. This can be confusing and no standard diagnostic SIJ MRI protocol is currently accepted worldwide. OBJECTIVE: To develop a standardised MRI image acquisition protocol (IAP) for diagnostic ascertainment of sacroiliitis. METHODS: 13 radiologist members of Assessment of SpondyloArthritis International Society (ASAS) and the SpondyloArthritis Research and Treatment Network (SPARTAN) plus two rheumatologists participated in a consensus exercise. A draft IAP was circulated with background information and online examples. Feedback on all issues was tabulated and recirculated. The remaining points of contention were resolved and the revised IAP was presented to the entire ASAS membership. RESULTS: A minimum four-sequence IAP is recommended for diagnostic ascertainment of sacroiliitis and its differential diagnoses meeting the following requirements. Three semicoronal sequences, parallel to the dorsal cortex of the S2 vertebral body, should include sequences sensitive for detection of (1) changes in fat signal and structural damage with T1-weighting; (2) active inflammation, being T2-weighted with fat suppression; (3) bone erosion optimally depicting the bone-cartilage interface of the articular surface and (4) a semiaxial sequence sensitive for detection of inflammation. The IAP was approved at the 2022 ASAS annual meeting with 91% of the membership in favour. CONCLUSION: A standardised IAP for SIJ MRI for diagnostic ascertainment of sacroiliitis is recommended and should be composed of at least four sequences that include imaging in two planes and optimally visualise inflammation, structural damage and the bone-cartilage interface.

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OBJECTIVES: To determine the prevalence of eczema among children in New Zealand. METHODS: Population-based retrospective observational study utilising national pharmaceutical dispensing records for topical corticosteroids and emollients for all New Zealand children aged 0-14 years from 1st January 2006 to 31st December 2019. Data are reported using descriptive statistics, with comparisons between ethnicities and socioeconomic quintiles undertaken with rate ratios. RESULTS: Based on dispensing data, the prevalence of eczema for New Zealand children aged 0-14 years in 2018 was 14.0% (95% CI 14.0%-14.1%), with prevalence decreasing in older age groups (children aged <1 year 26.0% (25.6%-26.4%); children aged 10-14 years 8.8% (8.7%-8.9%)). Prevalence was higher in Pacific children (23.6% (23.3%-24.0%)), but slightly lower in Maori children (13.2% (13.0%-13.3%)). CONCLUSION: Eczema is a common condition affecting a considerable proportion of children in New Zealand. This study provides nationwide paediatric prevalence data for New Zealand, and highlights the increased burden of eczema in Pacific children. Inequity in dispensing of topical corticosteroids is postulated to explain the reduced rates found for Maori children compared to previous studies. These results support the need for further research to determine factors contributing to differing eczema prevalence rates in New Zealand.

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In Maori and Pacific adults, the CREBRF rs373863828 minor (A) allele is associated with increased body mass index (BMI) but reduced incidence of type-2 and gestational diabetes mellitus. In this prospective cohort study of Maori and Pacific infants, nested within a nutritional intervention trial for pregnant women with obesity and without pregestational diabetes, we investigated whether the rs373863828 A allele is associated with differences in growth and body composition from birth to 12-18 months' corrected age. Infants with and without the variant allele were compared using generalised linear models adjusted for potential confounding by gestation length, sex, ethnicity and parity, and in a secondary analysis, additionally adjusted for gestational diabetes. Carriage of the rs373863828 A allele was not associated with altered growth and body composition from birth to 6 months. At 12-18 months, infants with the rs373863828 A allele had lower whole-body fat mass [FM 1.4 (0.7) vs. 1.7 (0.7) kg, aMD -0.4, 95% CI -0.7, 0.0, P = 0.05; FM index 2.2 (1.1) vs. 2.6 (1.0) kg/m2 aMD -0.6, 95% CI -1.2,0.0, P = 0.04]. However, this association was not significant after adjustment for gestational diabetes, suggesting that it may be mediated, at least in part, by the beneficial effect of CREBRF rs373863828 A allele on maternal glycemic status.

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Alpha-Synuclein (α-Syn) aggregation is a pathological feature of synucleinopathies, neurodegenerative disorders that include Parkinson's disease (PD). Here, we explored the efficacy of N,N,N',N'-tetraethyl-10H-phenothiazine-3,7-diamine dihydrochloride (LETC), a protein aggregation inhibitor, on α-Syn aggregation. In both cellular models and transgenic mice, α-Syn aggregation was achieved by the overexpression of full-length human α-Syn fused with a signal sequence peptide. α-Syn accumulated in transfected DH60.21 neuroblastoma cells and α-Syn aggregation was inhibited by LETC with an EC50 of 0.066 ± 0.047 µM. Full-length human α-Syn overexpressing Line 62 (L62) mice accumulated neuronal α-Syn that was associated with a decreased motor performance in the open field and automated home cage. LETC, administered orally for 6 weeks at 10 mg/kg significantly decreased α-Syn-positive neurons in multiple brain regions and this resulted in a rescue of movement deficits in the open field in these mice. LETC however, did not improve activity deficits of L62 mice in the home cage environment. The results suggest that LETC may provide a potential disease modification therapy in synucleinopathies through the inhibition of α-Syn aggregation.

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OBJECTIVE: To investigate associations of the Fetal Pillow® with maternal and neonatal morbidity. DESIGN: Retrospective cohort. SETTING: Two tertiary maternity units, New Zealand. POPULATION OR SAMPLE: Full dilatation singleton, term, cephalic caesarean section, with three comparisons: at Unit A (1) before versus after introduction of the Fetal Pillow® (1 Jaunary 2016-31 October 2021); (2) with versus without the Fetal Pillow® after introduction (27 July 2017-31 October 2021); and (3) between Unit A and Unit B during the same time period (1 January 2019-31 October 2021). The Fetal Pillow® is unavailable at Unit B. METHODS: Cases were ascertained and clinical data were extracted from electronic clinical databases and records. Outcome data were adjusted and presented as adjusted odds ratios (aOR) with 95% CI. MAIN OUTCOME MEASURES: Primary outcome "any" uterine incision extension; secondary outcomes included major extension (into adjacent structures), and a composite neonatal outcome. RESULTS: In all, 1703 caesareans were included; 375 with the device and 1328 without. Uterine incision extension rates were: at Unit A before versus after introduction: 26.8% versus 24.8% (aOR 0.88, 95% CI 0.65-1.19); at Unit A with the Fetal Pillow® versus without: 26.1% versus 23.8% (aOR 1.14, 95% CI 0.83-1.57); and at Unit A versus Unit B: 24.2% versus 29.2% (aOR 0.73, 95% CI 0.54-0.99). No differences were found in major extensions, or neonatal composite outcome. CONCLUSIONS: Despite the relatively large size of this study, it could not rule out either a positive or a negative association between use of the Fetal Pillow® and uterine extensions, major uterine incision extensions, and neonatal morbidity. Randomised controlled trial evidence is required to assess efficacy.

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The syntheses and characterisation of the 4-[{[4-({n-[4-(4-cyanophenyl)phenyl]-n-yl}oxy)phenyl]-methylidene}amino]phenyl-4-alkoxybenzoates (CBnOIBeOm) are reported with n=8 and 10 and m=1-10. The two series display fascinating liquid crystal polymorphism. All twenty reported homologues display an enantiotropic nematic (N) phase at high temperature. When the length of the spacer (n) is greater than that of the terminal chain (m), the twist-bend nematic (NTB) phase is observed at temperatures below the N phase. As the length of the terminal chain is increased and extends beyond the length of the spacer up to three smectic phases are observed on cooling the N phase. One of these smectic phases has been assigned as the rare twist-bend smectic C subphase, the SmCTB-α phase. In all the smectic phases, a monolayer packing arrangement is seen, and this is attributed to the anti-parallel associations of the like mesogenic units.

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INTRODUCTION: Birth at early term (37+0-38+6 completed gestational weeks [GW] and additional days) is associated with adverse neonatal outcomes compared with waiting to ≥39 GW. Most studies report outcomes after elective cesarean section or a mix of all modes of births; it is unclear whether these adverse outcomes apply to early-term babies born after induction of labor (IOL). We aimed to determine, in women with a non-urgent induction indication (elective/planned >48 h in advance), if IOL at early and late term was associated with adverse neonatal and maternal outcomes compared with IOL at full term. MATERIAL AND METHODS: An observational cohort study as a secondary analysis of a multicenter randomized controlled trial of 1087 New Zealand women with a planned IOL ≥37+0 GW. Multivariable logistic regression was used to analyze neonatal and maternal outcomes in relation to gestational age; 37+0-38+6 (early term), 39+0-40+6 (full term) and ≥41+0 (late term) GW. Neonatal outcome analyses were adjusted for sex, birthweight, mode of birth and induction indication, and maternal outcome analyses for parity, age, body mass index and induction method. The primary neonatal outcome was admission to neonatal intensive care unit (NICU) for >4 hours; the primary maternal outcome was cesarean section. RESULTS: Among the 1087 participants, 266 had IOL at early term, 480 at full term, and 341 at late term. Babies born following IOL at early term had increased odds for NICU admission for >4 hours (adjusted odds ratio [aOR] 2.16, 95% confidence intervals (CI) 1.16-4.05), compared with full term. Women having IOL at early term had no difference in emergency cesarean rates but had an increased need for a second induction method (aOR 1.70, 95% CI 1.15-2.51) and spent 4 h longer from start of IOL to birth (Hodges-Lehmann estimator 4.10, 95% CI 1.33-6.95) compared with those with IOL at full term. CONCLUSIONS: IOL for a non-urgent indication at early term was associated with adverse neonatal and maternal outcomes and no benefits compared with IOL at full term. These findings support international guidelines to avoid IOL before 39 GW unless there is an evidence-based indication for earlier planned birth and will help inform women and clinicians in their decision-making about timing of IOL.

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OBJECTIVE: We examined whether the risk of stillbirth was related to ambient air pollution in a UK population. DESIGN: Prospective case-control study. SETTING: Forty-one maternity units in the UK. POPULATION: Women who had a stillbirth ≥28 weeks' gestation (n = 238) and women with an ongoing pregnancy at the time of interview (n = 597). METHODS: Secondary analysis of data from the Midlands and North of England Stillbirth case-control study only including participants domiciled within 20 km of fixed air pollution monitoring stations. Pollution exposure was calculated using pollution climate modelling data for NO2 , NOx and PM2.5 . The association between air pollution exposure and stillbirth risk was assessed using multivariable logistic regression adjusting for household income, maternal body mass index (BMI), maternal smoking, Index of Multiple Deprivation quintile and household smoking and parity. MAIN OUTCOME MEASURE: Stillbirth. RESULTS: There was no association with whole pregnancy ambient air pollution exposure and stillbirth risk, but there was an association with preconceptual NO2 exposure (adjusted odds ratio [aOR] 1.06, 95% CI 1.01-1.08 per microg/m3 ). Risk of stillbirth was associated with maternal smoking (aOR 2.54, 95% CI 1.38-4.71), nulliparity (aOR 2.16, 95% CI 1.55-3.00), maternal BMI (aOR 1.05, 95% CI 1.01-1.08) and placental abnormalities (aOR 4.07, 95% CI 2.57-6.43). CONCLUSIONS: Levels of ambient air pollution exposure during pregnancy in the UK, all of were beneath recommended thresholds, are not associated with an increased risk of stillbirth. Periconceptual exposure to NO2 may be associated with increased risk but further work is required to investigate this association.

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We report two new series of compounds that show the ferroelectric nematic, NF, phase in which the terminal chain length is varied. The longer the terminal chain, the weaker the dipole-dipole interactions of the molecules are along the director and thus the lower the temperature at which the axially polar NF phase is formed. For homologues of intermediate chain lengths, between the non-polar and ferroelectric nematic phases, a wide temperature range nematic phase emerges with antiferroelectric character. The size of the antiparallel ferroelectric domains critically increases upon transition to the NF phase. In dielectric studies, both collective ("ferroelectric") and non-collective fluctuations are present, and the "ferroelectric" mode softens weakly at the N-NX phase transition because the polar order in this phase is weak. The transition to the NF phase is characterized by a much stronger lowering of the mode relaxation frequency and an increase in its strength, and a typical critical behavior is observed.

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Methylthioninium chloride (MTC) is a standard treatment for methaemoglobinaemia. A preparation of reduced MTC has been reported to increase blood oxygen saturation (SpO2) and lower respiratory rates in patients with severe COVID-19. We have developed a stable form of reduced methylthionine (hydromethylthionine-mesylate, HMTM) having a benign safety profile in two Phase 3 trials in Alzheimer's disease. The aim of this prospective study was to determine the effects of oral HMTM on SpO2 and methaemoglobin (metHb) levels in a cohort of patients with mild hypoxaemia not due to COVID-19. Eighteen participants randomised to a single dose of 4, 75, 100 or 125 mg doses of HMTM had SpO2 levels below 94% at baseline. Patients were routinely monitored by pulse oximetry after 4 h, and after 2 and 6 weeks of twice daily dosing. Significant ~3% increases in SpO2 occurred within 4 h and were sustained over 2 and 6 weeks with no dose differences. There were small dose-dependent increases (0.060-0.162%) in metHb levels over 2 to 6 weeks. Minimum-energy computational chemistry revealed that HMT can bind within 2.10 Å of heme iron by donating a pair of electrons from the central nitrogen of HMT to d orbitals of heme iron, but with lower affinity than oxygen. In conclusion, HMTM can increase SpO2 without reducing metHb by acting as a strong displaceable field ligand for heme iron. We hypothesise that this facilitates a transition from the low oxygen affinity T-state of heme to the higher affinity R-state. HMTM has potential as an adjunctive treatment for hypoxaemia.

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INTRODUCTION: Maternal perception of fetal movements during pregnancy are reassuring; however, the perception of a reduction in movements are concerning to women and known to be associated with increased odds of late stillbirth. Prior to full term, little evidence exists to provide guidelines on how to proceed unless there is an immediate risk to the fetus. Increased strength of movement is the most commonly reported perception of women through to full term, but perception of movement is also hypothesized to be influenced by fetal size. The study aimed to assess the pattern of maternal perception of strength and frequency of fetal movement by gestation and customized birthweight quartile in ongoing pregnancies. A further aim was to assess the association of stillbirth to perception of fetal movements stratified by customized birthweight quartile. MATERIAL AND METHODS: This analysis was an individual participant data meta-analyses of five case-control studies investigating factors associated with stillbirth. The dataset included 851 cases of women with late stillbirth (>28 weeks' gestation) and 2257 women with ongoing pregnancies who then had a liveborn infant. RESULTS: The frequency of prioritized fetal movement from 28 weeks' gestation showed a similar pattern for each quartile of birthweight with increased strength being the predominant perception of fetal movement through to full term. The odds of stillbirth associated with reduced fetal movements was increased in all quartiles of customized birthweight centiles but was notably greater in babies in the lowest two quartiles (Q1: adjusted OR: 9.34, 95% CI: 5.43, 16.06 and Q2: adjusted OR: 6.11, 95% CI: 3.11, 11.99). The decreased odds associated with increased strength of movement was present for all customized birthweight quartiles (adjusted OR range: 0.25-0.56). CONCLUSIONS: Increased strength of fetal movements in late pregnancy is a positive finding irrespective of fetal size. However, reduced fetal movements are associated with stillbirth, and more so when the fetus is small.

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Fetal growth restriction (FGR) and maternal supine going-to-sleep position are both risk factors for late stillbirth. This study aimed to use magnetic resonance imaging (MRI) to quantify the effect of maternal supine position on maternal-placental and fetoplacental blood flow, placental oxygen transfer and fetal oxygenation in FGR and healthy pregnancies. Twelve women with FGR and 27 women with healthy pregnancies at 34-38 weeks' gestation underwent MRI in both left lateral and supine positions. Phase-contrast MRI and a functional MRI technique (DECIDE) were used to measure blood flow in the maternal internal iliac arteries (IIAs) and umbilical vein (UV), placental oxygen transfer (placental flux), fetal oxygen saturation (FO2 ), and fetal oxygen delivery (delivery flux). The presence of FGR, compared to healthy pregnancies, was associated with a 7.8% lower FO2 (P = 0.02), reduced placental flux, and reduced delivery flux. Maternal supine positioning caused a 3.8% reduction in FO2 (P = 0.001), and significant reductions in total IIA flow, placental flux, UV flow and delivery flux compared to maternal left lateral position. The effect of maternal supine position on fetal oxygen delivery was independent of FGR pregnancy, meaning that supine positioning has an additive effect of reducing fetal oxygenation further in women with FGR, compared to women with appropriately grown for age pregnancies. Meanwhile, the effect of maternal supine positioning on placental oxygen transfer was not independent of the effect of FGR. Therefore, growth-restricted fetuses, which are chronically hypoxaemic, experience a relatively greater decline in oxygen transfer when mothers lie supine in late gestation compared to appropriately growing fetuses. KEY POINTS: Fetal growth restriction (FGR) is the most common risk factor associated with stillbirth, and early recognition and timely delivery is vital to reduce this risk. Maternal supine going-to-sleep position is found to increase the risk of late stillbirth but when combined with having a FGR pregnancy, maternal supine position leads to 15 times greater odds of stillbirth compared to supine sleeping with appropriately grown for age (AGA) pregnancies. Using MRI, this study quantifies the chronic hypoxaemia experienced by growth-restricted fetuses due to 13.5% lower placental oxygen transfer and 26% lower fetal oxygen delivery compared to AGA fetuses. With maternal supine positioning, there is a 23% reduction in maternal-placental blood flow and a further 14% reduction in fetal oxygen delivery for both FGR and AGA pregnancies, but this effect is proportionally greater for growth-restricted fetuses. This knowledge emphasises the importance of avoiding supine positioning in late pregnancy, particularly for vulnerable FGR pregnancies.

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A critical end point above which an isotropic phase continuously evolves into a polar (ferroelectric) nematic phase with an increasing electric field is found in a ferroelectric nematic liquid crystalline material. The critical end point is approximately 30 K above the zero-field transition temperature from the isotropic to nematic phase and at an electric field of the order of 10 V/µm. Such systems are interesting from the application point of view because a strong birefringence can be induced in a broad temperature range in an optically isotropic phase.

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Microsurgical breast reconstruction accounts for 22% of breast reconstructions in the UK. Despite thromboprophylaxis, venous thromboembolism (VTE) occurs in up to 4% of cases. Using a Delphi process, this study established a UK consensus on VTE prophylaxis strategy, for patients undergoing autologous breast reconstruction using free-tissue transfer. It captured geographically divergent views, producing a guide that reflected the peer opinion and current evidence base. METHODS: Consensus was ascertained using a structured Delphi process. A specialist from each of the UK's 12 regions was invited to the expert panel. Commitment to three to four rounds of questions was sought at enrollment. Surveys were distributed electronically. An initial qualitative free-text survey was distributed to identify likely lines of consensus and dissensus. Each panelist was provided with full-text versions of key papers on the topic. Initial free-text responses were analyzed to develop a set of structured quantitative statements, which were refined via a second survey as a consensus was approached. RESULTS: The panel comprised 18 specialists: plastic surgeons and thrombosis experts from across the UK. Each specialist completed three rounds of surveys. Together, these plastic surgeons reported having performed more than 570 microsurgical breast reconstructions in the UK in 2019. A consensus was reached on 27 statements, detailing the assessment and delivery of VTE prophylaxis. CONCLUSION: To our knowledge, this is the first study to collate current practice, expert opinion from across the UK, and a literature review. The output was a practical guide for VTE prophylaxis for microsurgical breast reconstruction in any UK microsurgical breast reconstruction unit.

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BACKGROUND: Approximately 1 in 4 pregnant women undergo induction of labor. Meta-analyses have shown that mechanical methods of induction of labor are safe and effective, as is starting induction in an outpatient setting. However, few studies have evaluated outpatient balloon catheter induction in comparison with pharmacologic methods. OBJECTIVE: This study aimed to determine whether women who underwent outpatient induction of labor with a balloon catheter would have a lower cesarean delivery rate than women who underwent inpatient induction of labor with vaginal prostaglandin E2 without an increase in adverse maternal or neonatal events. STUDY DESIGN: This was a superiority randomized controlled trial. The eligibility criteria were pregnant women (nullipara and multipara) with a live singleton fetus in vertex presentation with any medical comorbidity who underwent planned induction of labor at term and who had an initial modified Bishop Score of 0 to 6 at 1 of 11 public maternity hospitals in New Zealand. The intervention groups were outpatient single balloon catheter induction in comparison with inpatient vaginal prostaglandin E2 induction. The primary hypothesis was that participants who started their induction at home with a balloon catheter would have a lower risk for cesarean delivery than participants who started their induction with prostaglandins and remained in hospital throughout. The primary outcome was cesarean delivery rate. Participants were randomized using a centralized secure online randomization website in a 1:1 ratio, stratified by parity and hospital. The participants and outcome assessors were not blinded to group allocation. An intention-to-treat analysis with adjustment for stratification variables was used. RESULTS: A total of 539 participants were randomized to outpatient balloon catheter induction, and 548 participants were randomized to inpatient prostaglandin induction; the mode of birth was reported for all participants. The cesarean delivery rate was 41.0% among participants allocated to outpatient balloon induction and 35.2% among those allocated to inpatient prostaglandin induction (adjusted odds ratio, 1.27; 95% confidence interval, 0.98-1.65). Women in the outpatient balloon catheter group were more likely to have artificial rupture of membranes and to received oxytocin and an epidural. No differences were found in the rates of adverse maternal or neonatal events. CONCLUSION: Outpatient balloon catheter induction was not found to reduce the cesarean delivery rate when compared with inpatient vaginal prostaglandin E2 induction. The use of balloon catheters in an outpatient setting does not seem to increase the rate of adverse events for mothers or babies and can be offered routinely.

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The front cover artwork is provided by Dr Rebecca Walker of the Liquid Crystals Group at the University of Aberdeen. The image is a cartoon depiction of the formation of the heliconical chiral twist-bend nematic phase (N*TB ) from its constituent bent molecules. The presence of a single enantiomer of the chiral, lactate-based liquid crystal dimers biases the formation of helices with only one handedness, unlike in the conventional NTB phase, observed for achiral molecules, for which the left- and right-handed helices are doubly degenerate. Read the full text of the Research Article at 10.1002/cphc.202200807.

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OBJECTIVE: Identify independent and novel risk factors for late-preterm (28-36 weeks) and term (≥37 weeks) stillbirth and explore development of a risk-prediction model. DESIGN: Secondary analysis of an Individual Participant Data (IPD) meta-analysis investigating modifiable stillbirth risk factors. SETTING: An IPD database from five case-control studies in New Zealand, Australia, the UK and an international online study. POPULATION: Women with late-stillbirth (cases, n = 851), and ongoing singleton pregnancies from 28 weeks' gestation (controls, n = 2257). METHODS: Established and novel risk factors for late-preterm and term stillbirth underwent univariable and multivariable logistic regression modelling with multiple sensitivity analyses. Variables included maternal age, body mass index (BMI), parity, mental health, cigarette smoking, second-hand smoking, antenatal-care utilisation, and detailed fetal movement and sleep variables. MAIN OUTCOME MEASURES: Independent risk factors with adjusted odds ratios (aOR) for late-preterm and term stillbirth. RESULTS: After model building, 575 late-stillbirth cases and 1541 controls from three contributing case-control studies were included. Risk factor estimates from separate multivariable models of late-preterm and term stillbirth were compared. As these were similar, the final model combined all late-stillbirths. The single multivariable model confirmed established demographic risk factors, but additionally showed that fetal movement changes had both increased (decreased frequency) and reduced (hiccoughs, increasing strength, frequency or vigorous fetal movements) aOR of stillbirth. Poor antenatal-care utilisation increased risk while more-than-adequate care was protective. The area-under-the-curve was 0.84 (95% CI 0.82-0.86). CONCLUSIONS: Similarities in risk factors for late-preterm and term stillbirth suggest the same approach for risk-assessment can be applied. Detailed fetal movement assessment and inclusion of antenatal-care utilisation could be valuable in late-stillbirth risk assessment.

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The synthesis and characterisation of two series of low molar mass mesogens, the (4-nitrophenyl) 2-alkoxy-4-(4-methoxybenzoyl)oxybenzoates (NT3.m) and the (3-fluoro-4-nitrophenyl) 2-alkoxy-4-(4-methoxybenzoyl)oxybenzoates (NT3F.m), are reported in order to investigate the effect of changing the position of a lateral alkoxy chain from the methoxy-substituted terminal ring to the central phenyl ring in these two series of materials based on RM734. All members of the NT3.m series exhibited a conventional nematic phase, N, which preceded the ferroelectric nematic phase, NF , whereas all the members of the NT3F.m series exhibited direct NF -I transitions except for NT3F.1 which also exhibited an N phase. These materials cannot be described as wedge-shaped, yet their values of the ferroelectric nematic-nematic transition temperature, T N F N ${{_{{\rm N}{_{{\rm F}}}{\rm N}}}}$ , exceed those of the corresponding materials with the lateral alkoxy chain located on the methoxy-substituted terminal ring. In part, this may be attributed to the effect that changing the position of the lateral alkoxy chain has on the electronic properties of these materials, specifically on the electron density associated with the methoxy-substituted terminal aromatic ring. The value of TNI decreased with the addition of a fluorine atom ortho to the nitro group in NT3F.1, however, the opposite behaviour was found when the transition temperatures of the NF phase were compared which are higher for the NT3F.m series. This may reflect a change in the polarity and polarizability of the NT3F.m series compared to the NT3.m series. Therefore, it is suggested that, rather than simply promoting a tapered shape, the role of the lateral chain in inhibiting anti-parallel associations and its effect on the electronic properties of the molecules are the key factors in driving the formation of the NF phase.

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BACKGROUND: Presentations for decreased fetal movements comprise a significant proportion of acute antenatal assessments. Decreased fetal movements are associated with increased likelihood of adverse pregnancy outcomes including stillbirth. Consensus-based guidelines recommend pregnant women routinely receive information about fetal movements, but practice is inconsistent, and the information shared is frequently not evidence-based. There are also knowledge gaps about the assessment and management of fetal movement concerns. Women have indicated that they would like more accurate information about what to expect regarding fetal movements. DISCUSSION: Historically, fetal movement information has focussed on movement counts. This is problematic, as the number of fetal movements perceived varies widely between pregnant women, and no set number of movements has been established as a reliable indicator of fetal wellbeing. Of late, maternity care providers have also advised women to observe their baby's movement pattern, and promptly present if they notice a change. However, normal fetal movement patterns are rarely defined. Recently, a body of research has emerged relating to maternal perception of fetal movement features such as strength, presence of hiccups, and diurnal pattern as indicators of fetal wellbeing in addition to frequency. CONCLUSION: Sharing comprehensive and gestation-appropriate information about fetal movements may be more satisfying for women, empowering women to identify for themselves when their baby is doing well, and importantly when additional assessment is needed. We propose a conversational approach to fetal movement information sharing, focusing on fetal movement strength, frequency, circadian pattern, and changes with normal fetal development, tailored to the individual.

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The inclusion of secondary and tertiary benzanilide-based mesogenic groups into liquid crystal dimers is reported as a means to develop new materials. Furthermore, substitution at the nitrogen atom is shown to introduce an additional synthetic 'handle' to modify the molecular structure of the tertiary materials. The design of these materials has proved challenging due to the strong preferences of 3° benzanilides for the E amide conformation. In this work, lateral substitution is used to modify the conformational preferences of the amide linkage and promote liquid crystallinity for a series of N-methyl benzanilide dimers. As the proportion of the E conformer decreases, the nematic-isotropic transition temperatures increase, and enantiotropic nematic behaviour is observed. We also report the synthesis and characterisation of the analogous 2° benzanilide-based materials, which show nematic and twist-bend nematic behaviour. This approach highlights the effects that seemingly small structural modifications, such as the inclusion and position of a methyl group, can have on molecular shape and hence, liquid crystalline behaviour.