Evaporation‐induced intercalation of nanosheets of organosilica, organoclay or various organic polymers within the interlayer spaces of an oriented bacteriorhodopsin/lipid membrane mesolamellar film is used to prepare stable, self‐supporting biofunctional hybrid nanocomposites with photochromic and photoelectric properties. Compared with unmodified purple membrane films, mesolamellar nanocomposites containing intercalated organosilica exhibit enhanced stability in their photoelectric response at high relative humidity.

Introduction: To examine the prevalence and outcome of absent ductus venosus (DV) diagnosed at 11–13 weeks’ gestation. Method: Prospective screening study for aneuploidies in 65,840 singleton pregnancies, including measurement of nuchal translucency (NT) thickness and examination of the DV. Prenatal findings and outcome of fetuses with absent DV were examined. Results: Absent DV was diagnosed in 26 cases giving a prevalence of 1 in 2,532. In 15 (57.7%) cases the NT was above the 95th centile for crown-rump length. In 11 (42.3%) cases, there was an aneuploidy, mainly Turner syndrome. The incidence of aneuploidies was 66.7% (10 of 15) for those with NT above the 95th centile and 9.1% (1 of 11) in those with normal NT (p = 0.015). In addition to the aneuploidies, there were 3 cases with other abnormalities, including one case each of Ebstein anomaly, Noonan syndrome and Pierre Robin sequence. In 9 of the 11 (81.8%) fetuses with NT below the 95th centile, absent DV was an isolated finding and the pregnancies resulted in healthy live births. Conclusion: The prognosis of fetuses with absent DV depends on the measurement of NT thickness, being poor if the NT is increased and good if the NT is normal.

Objective To estimate the chorionic villus sampling (CVS)‐related risk of fetal loss in twin pregnancy after adjustment for chorionicity, nuchal translucency thickness (NT), intertwin discordance in crown–rump length (CRL), maternal demographic characteristics and serum pregnancy‐associated plasma protein‐A (PAPP‐A) and free β‐human chorionic gonadotropin (β‐hCG). Methods This was a multicenter study from eight fetal medicine units in which the leadership were trained at the Harris Birthright Research Centre for Fetal Medicine in London, UK, and in which the protocols for screening, invasive testing and pregnancy management are similar. Data were obtained prospectively from women with twin pregnancy undergoing routine ultrasound examination at 11–13 weeks' gestation. Multivariable logistic regression analysis with backward stepwise elimination was used to examine whether CVS provided a significant independent contribution to the prediction of risk of fetal loss after adjusting for maternal and pregnancy characteristics, including maternal age, racial origin and weight, method of conception, smoking status, parity, chorionicity, intertwin discordance in CRL, fetal NT ≥ 95th percentile and free β‐hCG and PAPP‐A multiples of the median. Similarly, within the CVS group, multivariable logistic regression analysis was used to investigate the effect of the number of intrauterine needle insertions and size of the needle on the risk of fetal loss. Results The study population of 8581 twin pregnancies undergoing ultrasound examination at 11–13 weeks' gestation included 316 dichorionic and 129 monochorionic twins that had CVS. First, in twin pregnancies undergoing CVS, compared to those not undergoing CVS, there was a 2‐fold increased risk of fetal loss at < 24 weeks' gestation and of loss at any stage in pregnancy. Second, the factors providing a significant independent contribution to the prediction of miscarriage or fetal loss in twin pregnancy were increased maternal weight, black racial origin, monochorionicity, and more so monoamnionicity, large intertwin discordance in CRL and increased fetal NT, and, in the case of fetal loss at any stage, there was also a contribution from assisted conception and low serum PAPP‐A. Third, after adjustment for maternal and pregnancy characteristics, CVS did not provide a significant contribution to the risk of fetal loss. Fourth, in twin pregnancies that had CVS, there was no significant contribution to fetal loss from the number of intrauterine needle insertions or needle size. Conclusion The 2‐fold increased risk of fetal loss following CVS in twin pregnancy can, to a great extent, be explained by maternal and pregnancy characteristics rather than the invasive procedure itself. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.