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A technique is described for determining lattice constants of polycrystalline monoclinic materials and partition of observed experimental error among the several constants. The technique is illustrated for uranium tetrafluoride. Precision of the method is typically ±0.01 to ±0.02 Å on the unit cell lengths, and ±4 to ±8 min on the angle between axes. This is of the order expected, were single-crystal techniques limited to the range of Bragg angles available.
This paper describes the imaging of fossils using elemental x-ray area mapping (EXAM). The technique utilizes a commercially available instrument originally designed for the silicon chip industry. The EXAM data are processed digitally with imaging software to remove surface irregularities and enhance specimen details. Applications of this technique to specimens with irregular surfaces are described.
To simulate effects of different scenarios of folic acid fortification of food on dietary folate equivalents (DFE) intake in an ethnically diverse sample of pregnant women.
A forty-four-item FFQ was used to evaluate dietary intake of the population. DFE intakes were estimated for different scenarios of food fortification with folic acid: (i) voluntary fortification; (ii) increased voluntary fortification; (iii) simulated bread mandatory fortification; and (iv) simulated grains-and-rice mandatory fortification.
Ethnically and socio-economically diverse cohort of pregnant women in New Zealand.
Pregnant women (n 5664) whose children were born in 2009–2010.
Participants identified their ethnicity as European (56·0 %), Asian (14·2 %), Māori (13·2 %), Pacific (12·8 %) or Others (3·8 %). Bread, breakfast cereals and yeast spread were main food sources of DFE in the two voluntary fortification scenarios. However, for Asian women, green leafy vegetables, bread and breakfast cereals were main contributors of DFE in these scenarios. In descending order, proportions of different ethnic groups in the lowest tertile of DFE intake for the four fortification scenarios were: Asian (39–60 %), Others (41–44 %), European (31–37 %), Pacific (23–26 %) and Māori (23–27 %). In comparisons within each ethnic group across scenarios of food fortification with folic acid, differences were observed only with DFE intake higher in the simulated grains-and-rice mandatory fortification v. other scenarios.
If grain and rice fortification with folic acid was mandatory in New Zealand, DFE intakes would be more evenly distributed among pregnant women of different ethnicities, potentially reducing ethnic group differences in risk of lower folate intakes.
Significant ethnic and socio-economic disparities exist in infectious diseases (IDs) rates in New Zealand, so accurate measures of these characteristics are required. This study compared methods of ascribing ethnicity and socio-economic status. Children in the Growing Up in New Zealand longitudinal cohort were ascribed to self-prioritised, total response and single-combined ethnic groups. Socio-economic status was measured using household income, and both census-derived and survey-derived deprivation indices. Rates of ID hospitalisation were compared using linked administrative data. Self-prioritised ethnicity was simplest to use. Total response accounted for mixed ethnicity and allowed overlap between groups. Single-combined ethnicity required aggregation of small groups to maintain power but offered greater detail. Regardless of the method used, Māori and Pacific children, and children in the most socio-economically deprived households had a greater risk of ID hospitalisation. Risk differences between self-prioritised and total response methods were not significant for Māori and Pacific children but single-combined ethnicity revealed a diversity of risk within these groups. Household income was affected by non-random missing data. The census-derived deprivation index offered a high level of completeness with some risk of multicollinearity and concerns regarding the ecological fallacy. The survey-derived index required extra questions but was acceptable to participants and provided individualised data. Based on these results, the use of single-combined ethnicity and an individualised survey-derived index of deprivation are recommended where sample size and data structure allow it.
To evaluate the sociodemographic and lifestyle factors associated with insufficient and excessive use of folic acid supplements (FAS) among pregnant women.
A pregnancy cohort to which multinomial logistic regression models were applied to identify factors associated with duration and dose of FAS use.
The Growing Up in New Zealand child study, which enrolled pregnant women whose children were born in 2009–2010.
Pregnant women (n 6822) enrolled into a nationally generalizable cohort.
Ninety-two per cent of pregnant women were not taking FAS according to the national recommendation (4 weeks before until 12 weeks after conception), with 69 % taking insufficient FAS and 57 % extending FAS use past 13 weeks’ gestation. The factors associated with extended use differed from those associated with insufficient use. Consistent with published literature, the relative risks of insufficient use were increased for younger women, those with less education, of non-European ethnicities, unemployed, who smoked cigarettes, whose pregnancy was unplanned or who had older children, or were living in more deprived households. In contrast, the relative risks of extended use were increased for women of higher socio-economic status or for whom this was their first pregnancy and decreased for women of Pacific v. European ethnicity.
In New Zealand, current use of FAS during pregnancy potentially exposes pregnant women and their unborn children to too little or too much folic acid. Further policy development is necessary to reduce current socio-economic inequities in the use of FAS.
Pre-school nutrition-related behaviours influence diet and development of lifelong eating habits. We examined the prevalence and congruence of recommended nutrition-related behaviours (RNB) in home and early childhood education (ECE) services, exploring differences by child and ECE characteristics.
Telephone interviews with mothers. Online survey of ECE managers/head teachers.
Children (n 1181) aged 45 months in the Growing Up in New Zealand longitudinal study.
A mean 5·3 of 8 RNB were followed at home, with statistical differences by gender and ethnic group, but not socio-economic position. ECE services followed a mean 4·8 of 8 RNB, with differences by type of service and health-promotion programme participation. No congruence between adherence at home and in ECE services was found; half of children with high adherence at home attended a service with low adherence. A greater proportion of children in deprived communities attended a service with high adherence, compared with children living in the least deprived communities (20 and 12 %, respectively).
Children, across all socio-economic positions, may not experience RNB at home. ECE settings provide an opportunity to improve or support behaviours learned at home. Targeting of health-promotion programmes in high-deprivation areas has resulted in higher adherence to RNB at these ECE services. The lack of congruence between home and ECE behaviours suggests health-promotion messages may not be effectively communicated to parents/family. Greater support is required across the ECE sector to adhere to RNB and promote wider change that can reach into homes.
Congenital genitourinary tract anomalies are some of the most commonly identified prenatal abnormalities, being identified in between 1 in 250 and 1 in 1000 pregnancies. They consist of a wide spectrum of heterogeneous malformations. Obstructive uropathies account for the majority of these abnormalities. the second-trimester detailed scan (often at 18+0–21+6 weeks) is the examination in which the majority of genitourinary abnormalities are diagnosed. However, with the widespread use of first-trimester ultrasound screening, severe renal anomalies and “megacystis” are being noted between 11+0 and 13+6 weeks. Additionally, third-trimester ultrasound may reveal late-onset uropathies, often associated with changes in liquor volume.
Recent archaeological investigations at Tipan Chen Uitz, Belize, yielded two remarkable Classic Maya ballplayer panels. Iconographic and glyphic analysis of these panels within a regional context provides new insights into large-scale socio-political relationships, demonstrating that the ballgame was an important means and mechanism for macro-political affiliation in the Maya Lowlands. The panels suggest that Tipan was part of a wider system of vassalage that tied it to other Maya centres, including Naranjo, a regional capital under the dominion of Calakmul where the Snake-Head dynasty held sway. The data presented here underpin a more general discussion of archaeological approaches to ancient interaction spheres.
Although quality of life (QoL) is receiving increasing attention in bipolar disorder (BD) research and practice, little is known about its naturalistic trajectory. The dual aims of this study were to prospectively investigate: (a) the trajectory of QoL under guideline-driven treatment and (b) the dynamic relationship between mood symptoms and QoL.
In total, 362 patients with BD receiving guideline-driven treatment were prospectively followed at 3-month intervals for up to 5 years. Mental (Mental Component Score – MCS) and physical (Physical Component Score – PCS) QoL were measured using the self-report SF-36. Clinician-rated symptom data were recorded for mania and depression. Multilevel modelling was used to analyse MCS and PCS over time, QoL trajectories predicted by time-lagged symptoms, and symptom trajectories predicted by time-lagged QoL.
MCS exhibited a positive trajectory, while PCS worsened over time. Investigation of temporal relationships between QoL and symptoms suggested bidirectional effects: earlier depressive symptoms were negatively associated with mental QoL, and earlier manic symptoms were negatively associated with physical QoL. Importantly, earlier MCS and PCS were both negatively associated with downstream symptoms of mania and depression.
The present investigation illustrates real-world outcomes for QoL under guideline-driven BD treatment: improvements in mental QoL and decrements in physical QoL were observed. The data permitted investigation of dynamic interactions between QoL and symptoms, generating novel evidence for bidirectional effects and encouraging further research into this important interplay. Investigation of relevant time-varying covariates (e.g. medications) was beyond scope. Future research should investigate possible determinants of QoL and the interplay between symptoms and wellbeing/satisfaction-centric measures of QoL.
We present preliminary results from a programme designed to produce deep images of radio source fields drawn from the Parkes 2700 MHz and Molongolo 408 MHz catalogues using the charge-coupled-device (CCD) camera system built at the Institute of Astronomy, Cambridge. The programme is directed at a search both for faint extensions and nebulosity around radio QSOs and BL Lac objects and for faint objects in otherwise empty radio source fields; a detailed examination of the morphology of selected radio galaxies is also included.
A rapid and dramatic change in our views of the Universe which we have witnessed during the past two decades or so is often compared with what happened at the time of Galileo. Revolutionary role of the optical telescope then may be analogized with that of space-astronomy today which has drastically opened the new observational window to the Universe. The revolution is ongoing with a rapid pace or even being accelerated.
To evaluate our results in treating Zenker's diverticulum via the transcervical approach, and to compare our experiences with a recent systematic review of both open and endoscopic approaches to the pharyngeal pouch.
An audit yielded 41 consecutive cases of Zenker's diverticulum treated between 2003 and 2013.
All 41 patients underwent transcervical cricopharyngeal myotomy; 29 sacs also required ‘inversion’. The median and mean length of hospital stay was 1 night and 2.5 nights respectively. The recurrence rate was 2.4 per cent and the complication rate was 9.8 per cent.
When compared to reported endoscopic techniques, transcervical cricopharyngeal myotomy (with or without inversion) in our unit resulted in: shorter hospital stay, a comparable complication rate and fewer recurrences.
Given the wealth of data, the rotation curve, and the necessity for out-of-plane hydrogen demonstrated in the preceding paper, it seems desirable to attempt to establish a systematic procedure for determining the three-dimensional distribution of hydrogen. Under the assumption of cylindrical rotation this is, in principle, possible for most of the galaxy.
A new hydrogen line survey of M31 is described. A rotation curve of the galaxy is derived from these data. The northern half of the rotation curve can be traced to 27 kpc, the southern to 30 kpc. They are in general agreement; both sides show an extensive region of essentially constant rotational velocity.
Aren’t there already plenty of excellent books on the topic of CFD? Yes, there are … if you are a graduate student who wants to learn the intricacies of numerical methods applied to solving the fundamental equations of fluid dynamics. However, we believe that a paradigm shift has taken place in CFD, where the development of algorithms and codes has largely been replaced by people applying well-established codes to real-world applications. While this is a natural progression in any field of science and engineering, we do not believe that the paradigm shift has filtered into the academic world. In academia, undergraduates learning about aerodynamics are still going through theories and applications that were being taught 40 or 50 years ago. We believe that it is time to write a book for people who want to be “intelligent users” of CA, not for those who want to continue developing CA tools. We strongly endorse the perspective of David Darmofal and Earll Murman of MIT (see AIAA Paper 2001–0870):
Within aerodynamics, the need for re-engineering the traditional curriculum is critical. Industry, government, and (to some extent) academia has seen a significant shift away from engineering science and highly specialized research-oriented personnel toward product development and systems-thinking personnel. While technical expertise in aerodynamics is required, it plays a less critical role in the design of aircraft than in previous generations. In addition to these influences, aerodynamics has been revolutionized by the development and maturation of computational methods. These factors cast significant doubt that a traditional aerodynamics curriculum with its largely theoretical approach remains the most effective education for the next generation of aerospace engineers. We believe that change is in order.
We agree completely and believe that CA needs to be brought into the undergraduate classroom as soon as possible. That is why we have written this book!
The target audience for Applied Computational Aerodynamics is advanced undergraduates in aerospace engineering who want (or need) to learn CA in the broad context of learning to do computational investigations, while also learning engineering methods and aerodynamics. In addition, we believe that working engineers who need to apply CA methods, but who have no CA background, will also find the book valuable.