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We report on the detailed characterization of the HD 77946 planetary system. HD 77946 is an F5 (M *  = 1.17 M⊙, R *  = 1.31 R⊙) star, which hosts a transiting planet recently discovered by NASA's Transiting Exoplanet Survey Satellite (TESS), classified as TOI-1778 b. Using TESS photometry, high-resolution spectroscopic data from HARPS-N, and photometry from CHEOPS , we measure the radius and mass from the transit and radial velocity observations, and find that the planet, HD 77946 b, orbits with period P b  =  |$6.527282_{-0.000020}^{+0.000015}$| d, has a mass of M b = 8.38 ± 1.32 M⊕, and a radius of |$R_{\rm b} = 2.705_{-0.081}^{+0.086}$| R⊕. From the combination of mass and radius measurements, and the stellar chemical composition, the planet properties suggest that HD 77946 b is a sub-Neptune with a ∼1  per cent H/He atmosphere. However, a degeneracy still exists between water-world and silicate/iron-hydrogen models, and even though interior structure modelling of this planet favours a sub-Neptune with a H/He layer that makes up a significant fraction of its radius, a water-world composition cannot be ruled out, as with |$T_{\rm eq}~= 1248^{+40}_{-38}~$| K, water may be in a supercritical state. The characterization of HD 77946 b, adding to the small sample of well-characterized sub-Neptunes, is an important step forwards on our journey to understanding planetary formation and evolution pathways. Furthermore, HD 77946 b has one of the highest transmission spectroscopic metrics for small planets orbiting hot stars, thus transmission spectroscopy of this key planet could prove vital for constraining the compositional confusion that currently surrounds small exoplanets. [ABSTRACT FROM AUTHOR]

A total of 91 children (68 singletons, 20 twins and three triplets) who were conceived from cryopreserved embryos between 27 December 1989 and 18 January 1994, and 83 normally conceived control children (81 singletons and two twins) of a similar age, sex and social class, were assessed for minor congenital anomalies and major congenital malformations. Their development was assessed using the Griffiths Scales of Mental Development. The incidence of minor congenital anomalies (31.9% in the cryopreserved embryo group and 21.7% in the controls) and major congenital malformations (3.3 and 2.4% respectively) in our two groups of children was statistically similar. The relative risk (odds ratio and 95% confidence interval) in the cryopreserved embryo group compared with the controls was 1.7 (0.8, 3.3) for minor congenital anomalies and 1.4 (0.2, 8.5) for major congenital malformations. The minor congenital anomalies were mostly naevi and haemangiomas. The major congenital malformations included Down's syndrome, Beckwith-Wiedemann syndrome and hypophosphataemic rickets in the cryopreserved embryo group and hydronephrosis and gastroschisis in the controls. The Griffiths assessment showed that children from the cryopreserved embryo group and the controls were functioning at a similar level. The mean Griffiths quotient and subquotient values were greater than the standard 100 in children with or without congenital abnormalities. These results in the cryopreserved embryo group are reassuring in that the minor congenital anomaly and major congenital malformation rates were similar to those in normally conceived children of a similar age, sex and social class and their development was not adversely affected by cryopreservation. [ABSTRACT FROM AUTHOR]