Feed system design and experimental results in the uhf model study for the proposed Urbana phased array

The effects of atmospheric turbulence and the basis for the coherent scatter radar techniques are discussed. The reasons are given for upgrading the Radar system to a larger steerable array. Phase array theory pertinent to the system design is reviewed, along with approximations for maximum directive gain and blind angles due to mutual coupling. The methods and construction techniques employed in the UHF model study are explained. The antenna range is described, with a block diagram for the mode of operation used

Academic achievement at ages 11 and 16 in children born with congenital anomalies in England: A multi-registry linked cohort study

\ua9 2024 The Authors. Paediatric and Perinatal Epidemiology published by John Wiley & Sons Ltd. Background: Children born with major congenital anomalies (CAs) have lower academic achievement compared with their peers, but the existing evidence is restricted to a number of specific CAs. Objectives: To investigate academic outcomes at ages 11 and 16 in children with major isolated structural CAs and children with Down or Turner syndromes. Methods: This population-based cohort study linked data on approximately 11,000 school-aged children born with major CAs in 1994–2004 registered by four regional CA registries in England with education data from the National Pupil Database (NPD). The comparison group was a random sample of children without major CAs from the background population recorded in the NPD that were frequency matched (5:1) to children with CAs by birth year, sex and geographical area. Results: Overall, 71.9%, 73.0% and 80.9% of children with isolated structural CAs achieved the expected attainment level at age 11 compared to 78.3%, 80.6% and 86.7% of the comparison group in English language, Mathematics and Science, respectively. Children with nervous system CAs as a whole had the lowest proportion who achieved the expected attainment at age 11. At age 16, 46.9% of children with CAs achieved the expected level compared to 52.5% of their peers. Major CAs were associated with being up to 9% (95% confidence interval [CI] 8%, 11%) and 12% (95% CI 9%, 14%) less likely to achieve expected levels at ages 11 and 16, respectively, after adjustment for socioeconomic deprivation. Conclusions: Although many children with isolated CAs achieved the expected academic level at ages 11 and 16, they were at higher risk of underachievement compared to their peers. These stark yet cautiously encouraging results are important for counselling parents of children with specific CAs and also highlight the possible need for special education support to reduce potential academic difficulties

Column ratio mapping: a processing technique for atomic resolution high angle annular dark field(HAADF) images

An image processing technique is presented for atomic resolution high-angle annular dark-field (HAADF) images that have been acquired using scanning transmission electron microscopy (STEM). This technique is termed column ratio mapping and involves the automated process of measuring atomic column intensity ratios in high-resolution HAADF images. This technique was developed to provide a fuller analysis of HAADF images than the usual method of drawing single intensity line profiles across a few areas of interest. For instance, column ratio mapping reveals the compositional distribution across the whole HAADF image and allows a statistical analysis and an estimation of errors. This has proven to be a very valuable technique as it can provide a more detailed assessment of the sharpness of interfacial structures from HAADF images. The technique of column ratio mapping is described in terms of a [1 1 0]-oriented zinc-blende structured AlAs/GaAs superlattice using the 1 Å-scale resolution capability of the aberration-corrected SuperSTEM 1 instrument

Educational achievement of children with selected major congenital anomalies and associated factors: a Finnish registry-based study

\ua9 The Author(s) 2023. Published by Oxford University Press on behalf of the European Public Health Association. BACKGROUND: Children with major congenital anomalies may be at risk of poor educational outcomes. We aimed to evaluate the educational achievement of children born with major congenital anomalies compared with children without major congenital anomalies in relation to sociodemographic factors. METHODS: We performed a registry-based study including 401 544 children in Finland, graduates of the compulsory school who applied to secondary education. We used health data from the Finnish Register of Congenital Malformations for children born from 1995 to 2002 linked with education data from the Finnish Ministry of Education and Culture. We used generalized linear regression to compare the mean grade differences of children with specific major congenital anomalies and \u27All anomalies\u27 subgroup (major congenital anomalies, chromosomal syndromes, and multiple anomalies) with reference children. RESULTS: Children with major congenital anomalies were less likely to apply for further education than reference children (88.0% vs. 96.8%; odds ratio = 4.13; 95% confidence interval, 3.92-4.36). For most non-chromosomal congenital anomalies, children born with congenital anomalies had similar educational achievement to the reference children. For the \u27All anomalies\u27 subgroup, children with congenital anomalies had lower educational achievement than reference children. Among children with congenital anomalies, male sex, lower maternal educational levels and younger maternal age were associated with lower educational achievement. CONCLUSIONS: For children applying to further education, most non-chromosomal congenital anomalies were not associated with lower educational achievement. Nevertheless, efforts are needed to improve educational achievement in children with major congenital anomalies associated with maternal sociodemographic background

Academic achievement at ages 11 and 16 in children born with congenital anomalies in England: A multi‐registry linked cohort study

Background: Children born with major congenital anomalies (CAs) have lower academic achievement compared with their peers, but the existing evidence is restricted to a number of specific CAs. Objectives: To investigate academic outcomes at ages 11 and 16 years in children with major isolated structural CAs and children with Down or Turner syndromes.Methods: This population-based cohort study linked data on approximately 11,000 school-aged children born with major CAs in 1994-2004 registered by four regional CA registries in England with education data from the National Pupil Database (NPD). The comparison group was a random sample of children without major CAs from the background population recorded in the NPD that were frequency matched (5:1) to children with CAs by birth year, sex and geographical area.Results: Overall, 71.9%, 73.0% and 80.9% of children with isolated structural CAs achieved the expected attainment level at age 11 compared to 78.3%, 80.6% and 86.7% of the comparison group in English language, mathematics and science respectively. Children with nervous system CAs as a whole had the lowest proportion who achieved the expected attainment at age 11. At age 16, 46.9% of children with CAs achieved the expected level compared to 52.5% of their peers. Major CAs were associated with being up to 9% (95% CI 8%, 11%) and 12% (95% CI 9%, 14%) less likely to achieve expected levels at ages 11 and 16 respectively, after adjustment for socioeconomic deprivation.Conclusions: Although many children with isolated CAs achieved the expected academic level at age 11 and 16 years, they were at higher risk of underachievement compared to their peers. These stark yet cautiously encouraging results are important for counselling parents of children with specific CAs and also highlight the possible need for special education support to reduce potential academic difficulties.<br/

Experimental evaluation of interfaces using atomic-resolution high angle annular dark field (HAADF) imaging

Aberration-corrected highangleannulardarkfield (HAADF) imaging in scanning transmission electron microscopy (STEM) can now be performed at atomic-resolution. This is an important tool for the characterisation of the latest semiconductor devices that require individual layers to be grown to an accuracy of a few atomic layers. However, the actual quantification of interfacial sharpness at the atomic-scale can be a complicated matter. For instance, it is not clear how the use of the total, atomic column or background HAADF signals can affect the measured sharpness or individual layer widths. Moreover, a reliable and consistent method of measurement is necessary. To highlight these issues, two types of AlAs/GaAs interfaces were studied in-depth by atomic-resolutionHAADFimaging. A method of analysis was developed in order to map the various HAADF signals across an image and to reliably determine interfacial sharpness. The results demonstrated that the level of perceived interfacial sharpness can vary significantly with specimen thickness and the choice of HAADF signal. Individual layer widths were also shown to have some dependence on the choice of HAADF signal. Hence, it is crucial to have an awareness of which part of the HAADF signal is chosen for analysis along with possible specimen thickness effects for future HAADF studies performed at the scale of a few atomic layers