Video Evidence That London Infants Can Resettle Themselves Back to Sleep After Waking in the Night, as well as Sleep for Long Periods, by 3 Months of Age

Objective: Most infants become settled at night by 3 months of age, whereas infants not settled by 5 months are likely to have long-term sleep-waking problems. We assessed whether normal infant development in the first 3 months involves increasing sleep-period length or the ability to resettle autonomously after waking in the night. Methods: One hundred one infants were assessed at 5 weeks and 3 months of age using nighttime infrared video recordings and parental questionnaires. Results: The clearest development was in sleep length; 45% of infants slept continuously for 5 hours or more at night at 3 months compared with 10% at 5 weeks. In addition, around a quarter of infants woke and resettled themselves back to sleep in the night at each age. Autonomous resettling at 5 weeks predicted prolonged sleeping at 3 months suggesting it may be a developmental precursor. Infants reported by parents to sleep for a period of 5 hours or more included infants who resettled themselves and those with long sleeps. Three-month olds fed solely breast milk were as likely to self-resettle or have long sleep bouts as infants fed formula or mixed breast and formula milk. Conclusions: Infants are capable of resettling themselves back to sleep in the first 3 months of age; both autonomous resettling and prolonged sleeping are involved in “sleeping through the night” at an early age. Findings indicate the need for physiological studies of how arousal, waking, and resettling develop into sustained sleeping and of how environmental factors support these endogenous and behavioral processes

Experimental studies of hypersonic boundary-layer transition and effects of wind tunnel disturbances

Boundary layer transition data on cones and free stream disturbance levels were measured in a hypersonic wind tunnel and Mach 8 variable density hypersonic tunnel. Transition data were obtained by using different conical models and techniques for detecting the location of transition. The disturbance levels were measured by using hot wire anemometry and pressure transducers. The transition Reynolds numbers obtained from the tests correlated well when the fluctuating pressures measured at the surface of conical models were used as a correlating parameter

Effects of Herbicide-Resistant Technology Fees on the Plant Population Decision for Cotton Production

This study evaluated effects on cotton net revenues of four herbicide-resistant technology policies used since 1996 by Monsanto. Results indicate that farmers may have an incentive to switch from narrow-row to wide-row cotton and to use a lower plant density when the technology fee is tied to the seeding rate.Farm Management,

Evaluation of flow quality in two large NASA wind tunnels at transonic speeds

Wind tunnel testing of low drag airfoils and basic transition studies at transonic speeds are designed to provide high quality aerodynamic data at high Reynolds numbers. This requires that the flow quality in facilities used for such research be excellent. To obtain a better understanding of the characteristics of facility disturbances and identification of their sources for possible facility modification, detailed flow quality measurements were made in two prospective NASA wind tunnels. Experimental results are presented of an extensive and systematic flow quality study of the settling chamber, test section, and diffuser in the Langley 8 foot transonic pressure tunnel and the Ames 12 foot pressure wind tunnel. Results indicate that the free stream velocity and pressure fluctuation levels in both facilities are low at subsonic speeds and are so high as to make it difficult to conduct meaningful boundary layer control and transition studies at transonic speeds

OPTIMAL PLANT POPULATION FOR ULTRA-NARROW-ROW COTTON PRODUCTION AS INFLUENCED BY LINT AND TRANSGENIC SEED PRICES

Farmers are concerned about the high costs of transgenic seed and technology fees associated with the large plant population densities recommended for ultra-narrow row cotton. This study evaluated the effects of alternative plant population density decision criteria on net revenues under different lint price and transgenic seed cost scenarios. Results indicate that farmers may be able to maximize profits by seeding for a target plant population density of approximately 15.5 plants m-2.Crop Production/Industries,

Is Targeting Formal Childcare the Best Way to Meet the Needs of Families in Britain?

The overall aim of this paper is to examine the types and combinations of childcare being used by parents in Britain, and to compare how this childcare usage may vary between families, in order to critically examine parental childcare needs. The three specific research questions were: 1) ‘What types and combinations of childcare are being used by families?’, 2) ‘What are the socio-demographic comparisons between families using and not using childcare?’ And 3) ‘How do types of childcare vary between families?. These questions were addressed by carrying out a secondary analysis of large-scale nationally representative datasets which provide information about patterns of childcare usage in the UK. Two main datasets were used: the Family Resources Survey and the Childcare and Early Years Survey of Parents, with analysis carried out for the years 2008 to 2013. The analysis carried out comes from a wider study seeking to examine the provision and use of preschool childcare in Britain. The findings show that despite policies to increase the use of formal childcare, parents continue to be reliant on informal care, especially grandparents, to supplement their childcare needs. Furthermore, childcare use is not equally distributed, but is related to family circumstances. For example formal care is used more by employed, higher income families, whilst informal care is used more by mothers who are not employed, less well educated and by younger mothers. The results overall suggest that formal and informal childcare in combination will better support maternal employment. Future government policy needs to address supporting this mixed provision. The data however says nothing about parental childcare preferences which are needed to unpack the observed patterns of childcare usage in the UK

Is the ‘quality’ of preschool childcare, measured by the qualifications and pay of the childcare workforce, improving in Britain?

The purpose of this paper is to report on the changing qualifications, pay and working conditions of the British childcare workforce between 2005 and 2014. This is in order to contribute to current debates on the ‘quality’ of childcare provision for preschool children. The theoretical framework for this study draws upon concepts of 'quality' in childcare, to discuss the argued importance of increasing access to and raising standards of childcare for children’s cognitive development, for women’s labour market participation and for reducing poverty. The analysis comes from an ESRC funded study entitled ‘Provision and use of preschool childcare in Britain’. This paper focuses on examination of childcare provision by the formal childcare workforce and presents results from a secondary analysis of the UK’s Labour Force Survey, Childcare and Early Years Providers Survey, Annual Survey of Hours and Earnings, and Ofsted registration data. The 2005-2014 results show a highly gendered (98% female), low valued workforce in which qualifications are modestly rising (12% increase over time in NVQ level 3) but persistently low paid (on average £6.60 per hour) compared with other occupations (£13.10 per hour). The study also finds a shrinkage in the childcare workforce - of around five per cent in Britain since 2005 (from 329k in 2005-07 to 313k in 2012-14) – and more people describing themselves as childminders in the LFS than are registered with Ofsted, suggesting a possible growth in illegal childminding. The implications of these findings raise questions about what the British childcare workforce will look like in the future, who will do childcare work in the future, and whether it is possible to achieve ‘good quality’, ‘affordable childcare’ and ‘decent pay’ for British childcare workers. These issues are important for the future regulation of the British ‘childcare’ workforce and policy development in this vital area

Stereoelectronic effects on the binding of neutral Lewis bases to CdSe nanocrystals

Using P-31 nuclear magnetic resonance (NMR) spectroscopy, we monitor the competition between tri-nbutylphosphine (Bu3P) and various amine and phosphine ligands for the surface of chloride terminated CdSe nanocrystals. Distinct P-31 NMR signals for free and bound phosphine ligands allow the surface ligand coverage to be measured in phosphine solution. Ligands with a small steric profile achieve higher surface coverages (Bu3P = 0.5 nm(-2), Me2P-n-octyl = 2.0 nm(-2), NH2Bu = >3 nm(-2)) and have greater relative binding affinity for the nanocrystal (binding affinity: Me3P > Me2P -n-octyl similar to Me2P -n-octadecyl > Et3P > Bu3P). Among phosphines, only Bu 3 P and Me2P-n-octyl support a colloidal dispersion, allowing a relative surface binding affinity (K-rel) to be estimated in that case (K-rel = 3.1). The affinity of the amine ligands is measured by the extent to which they displace Bu3P from the nanocrystals (K-rel: H2NBu similar to N-n-butylimidazole > 4-ethylpyridine > Bu3P similar to HNBu2 > Me2NBu > Bu3N). The affinity for the CdSe surface is greatest among soft, basic donors and depends on the number of each ligand that bind. Sterically unencumbered ligands such as imidazole, pyridine, and n-alkylamines can therefore outcompete stronger donors such as alkylphosphines. The influence of repulsive interactions between ligands on the binding affinity is a consequence of the high atom density of binary semiconductor surfaces. The observed behavior is distinct from the self-assembly of straight-chain surfactants on gold and silver where the ligands are commensurate with the underlying lattice and attractive interactions between aliphatic chains strengthen the binding