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The mechanism through which developmental programming of offspring overweight/obesity following in utero exposure to maternal overweight/obesity operates is unknown but may operate through biologic pathways involving offspring anthropometry at birth. Thus, we sought to examine to what extent the association between in utero exposure to maternal overweight/obesity and childhood overweight/obesity is mediated by birth anthropometry. Analyses were conducted on a retrospective cohort with data obtained from one hospital system. A natural effects model framework was used to estimate the natural direct effect and natural indirect effect of birth anthropometry (weight, length, head circumference, ponderal index, and small-for-gestational age [SGA] or large-for-gestational age [LGA]) for the association between pre-pregnancy maternal body mass index (BMI) category (overweight/obese vs normal weight) and offspring overweight/obesity in childhood. Models were adjusted for maternal and child socio-demographics. Three thousand nine hundred and fifty mother–child dyads were included in analyses (1467 [57.8%] of mothers and 913 [34.4%] of children were overweight/obese). Results suggest that a small percentage of the effect of maternal pre-pregnancy BMI overweight/obesity on offspring overweight/obesity operated through offspring anthropometry at birth (weight: 15.5%, length: 5.2%, head circumference: 8.5%, ponderal index: 2.2%, SGA: 2.9%, and LGA: 4.2%). There was a small increase in the percentage mediated when gestational diabetes or hypertensive disorders were added to the models. Our study suggests that some measures of birth anthropometry mediate the association between maternal pre-pregnancy overweight/obesity and offspring overweight/obesity in childhood and that the size of this mediated effect is small.
To characterize the association of longitudinal changes in maternal anthropometric measures with neonatal anthropometry and to assess to what extent late-gestational changes in maternal anthropometry are associated with neonatal body composition.
In a prospective cohort of pregnant women, maternal anthropometry was measured at six study visits across pregnancy and after birth, neonates were measured and fat and lean mass calculated. We estimated maternal anthropometric trajectories and separately assessed rate of change in the second (15–28 weeks) and third trimester (28–39 weeks) in relation to neonatal anthropometry. We investigated the extent to which tertiles of third-trimester maternal anthropometry change were associated with neonatal outcomes.
Women were recruited from twelve US sites (2009–2013).
Non-obese women with singleton pregnancies (n 2334).
A higher rate of increase in gestational weight gain was associated with larger-birth-weight infants with greater lean and fat mass. In contrast, higher rates of increase in maternal anthropometry measures were not associated with infant birth weight but were associated with decreased neonatal lean mass. In the third trimester, women in the tertile of lowest change in triceps skinfold (−0·57 to −0·06 mm per week) had neonates with 35·8 g more lean mass than neonates of mothers in the middle tertile of rate of change (−0·05 to 0·06 mm per week).
The rate of change in third-trimester maternal anthropometry measures may be related to neonatal lean and fat mass yet have a negligible impact on infant birth weight, indicating that neonatal anthropometry may provide additional information over birth weight alone.
Surficial stratigraphic units of Aroostook County, Maine, have been mapped and formal stratigraphic names for these units are proposed. Evidence exists for at least two distinct glacial phases which are represented by three tills. Two of these tills were deposited penecontemporaneously either as the result of coalescing ice sheets or as the result of the thermal regime existing within a single ice sheet. The oldest till is named the St. Francis and is correlated with the Chaudière Till of southeastern Quebec. The other tills are named the Mars Hill and Van Buren tills, respectively, and are correlated with the Lennoxville till of southeastern Quebec. Interbedded stratified sediments associated with the St. Francis till are correlated with the Gayhurst Formation. Stratified sediments associated with Van Buren and Mars Hill tills are correlated with post Lennoxville sediments of Quebec. Granite-gneiss erratics of Canadian Shield provenance in the Van Buren till indicate advance of the Laurentide ice into northern Maine during late Wisconsinan time. Moraines in southern Aroostook County with associated outwash and eskers record general recession from coastal Maine. Recession occurred after the formation of the Pineo Ridge moraine in Maine and the St. Antonin-Highland Front moraine complex in Quebec. The Caribou-Winterville moraine complex in northern Maine marks the boundary between the penecontemporaneously deposited Van Buren and Mars Hill surface tills and is correlated with the Grand Falls moraine at Grand Falls, New Brunswick.
Trapped waves can exist in the presence of bodies in open water, and also in channels of finite width. Various examples are found for bodies that support trapped waves in channels, including floating and submerged bodies and bottom-mounted cylinders. Different types of trapping are considered where the body is fixed or free to move in response to the oscillatory pressure. In some cases both types are supported by the same body. In most cases for fixed bodies the fluid motion is antisymmetric about the centreline of the channel, but special body shapes exist where the trapped mode is asymmetric. For free bodies the trapping modes and body motions are symmetric about the centreline if the body is floating or antisymmetric if it is submerged.
Lectotypes are designated for eight names in Eriocaulon in tropical Asia, namely E. alatum, E. hamiltonianum, E. hookerianum, E. infirmum, E. lanigerum, E. nautiliforme, E. nigrum and E. ubonense. Additional information on the lectotype of Eriocaulon quinquangulare is given.
Objectives: A limited body of research is available on the relationships between multiplicity of birth and neuropsychological functioning in preterm children who were conceived in the age of assisted reproductive technology and served by the modern neonatal intensive care unit. Our chief objective was to evaluate whether, after adjustment for sociodemographic factors and perinatal complications, twin birth accounted for a unique portion of developmental outcome variance in children born at-risk in the surfactant era. Methods: We compared the neuropsychological functioning of 77 twins and 144 singletons born preterm (<34 gestational weeks) and served by William Beaumont Hospital, Royal Oak, MI. Children were evaluated at preschool age, using standardized tests of memory, language, perceptual, and motor abilities. Results: Multiple regression analyses, adjusting for sociodemographic and perinatal variables, revealed no differences on memory or motor indices between preterm twins and their singleton counterparts. In contrast, performance of language and visual processing tasks was significantly lower in twins despite reduced perinatal risk in comparison to singletons. Effect sizes ranged from .33 to .38 standard deviations for global language and visual processing ability indices, respectively. No significant group by sex interactions were observed, and comparison of first-, or second-born twins with singletons yielded medium effect sizes (Cohen’s d=.56 and .40, respectively). Conclusions: The modest twin disadvantage on language and visual processing tasks at preschool-age could not be readily attributable to socioeconomic or perinatal variables. The possibility of biological or social twinning-related phenomena as mechanisms underlying the observed performance gaps are discussed. (JINS, 2016, 22, 865–877)
There is increasing interest among developmental psychopathologists in broad transdiagnostic factors that give rise to a wide array of clinical presentations (multifinality), but little is known about how these processes lead to particular psychopathological manifestations over the course of development. We examined whether individual differences in the error-related negativity (ΔERN), a neural indicator of error monitoring, predicts whether early persistent irritability, a prototypical transdiagnostic construct, is associated with later internalizing versus externalizing outcomes. When children were 3 years old, mothers were interviewed about children's persistent irritability and completed questionnaires about their children's psychopathology. Three years later, EEG was recorded while children performed a go/no-go task to measure the ΔERN. When children were approximately 9 years old, mothers again completed questionnaires about their children's psychopathology. The results indicated that among children who were persistently irritable at age 3, an enhanced or more negative ΔERN at age 6 predicted the development of internalizing symptoms at age 9, whereas a blunted or smaller ΔERN at age 6 predicted the development of externalizing symptoms. Our results suggest that variation in error monitoring predicts, and may even shape, the expression of persistent irritability and differentiates developmental trajectories from preschool persistent irritability to internalizing versus externalizing outcomes in middle to late childhood.
Compounding offers a way of advancing the performance of the standard helicopter significantly for a moderate increase in complexity through the addition of wings and/or auxiliary propulsion. The compound helicopter configuration has the potential advantages of increased speed, range, agility, productivity and reduced vibration levels over conventional helicopters. Despite several significant efforts, however, no compound helicopter has ever been put into production. This paper looks at three aircraft that came close to being accepted by operators and examines the reasons why they were not ultimately put into production. The cancellation of these projects appeared to be of a political nature rather than technical. Also addressed are the issues that still face prospective designers of compound helicopters and the lessons that can be extracted and applied to modern day efforts to build and sell an aircraft of this configuration.
The interaction of a helicopter tail rotor blade with the tip vortex system from the main rotor is a significant source of noise and, in some flight states, can produce marked reductions in control effectiveness. This paper describes a series of wind-tunnel tests to simulate tail rotor blade vortex interaction with a view to providing data for the development and validation of numerical simulations of the phenomenon. In the experiments, which were carried out in the Argyll wind-tunnel of Glasgow University, a single-bladed rotor located in the tunnel’s contraction was used to generate the tip vortex which travelled downstream into the working section where it interacted with a model tail rotor. The tail rotor was instrumented with miniature pressure transducers that measured the aerodynamic response during the interaction. The results suggest that the rotor blade vortex interaction is similar in form to that measured at much higher spatial resolution on a fixed, non-rotating blade. The combination of the two datasets, therefore, provides a valuable resource for the development and validation of predictive schemes.
A study of the course of 17 patients with subacute polyneuritis was undertaken. Ten were given corticosteroids. Assessment of time of turnaround, that is the beginning of clinical improvement, showed that some patients responded promptly to steroids whereas a few did not. A comparison of turnaround times between the treated and untreated cases shows a statistically significant effect of steroids in hastening the onset of recovery. This is not due to bias in selection of those for steroid treatment.
We wanted to present our experience with the extended endoscopic approach to clival pathology, focusing on cerebrospinal fluid leak and reconstruction challenges.
We examined a consecutive series of 37 patients undergoing the extended endoscopic approach for skull base tumours, 9 patients with clival pathology. Patients were examined for the incidence of post-operative cerebrospinal fluid leak in relation to tumour pathology, location, size, reconstruction and lumbar drain.
The overall incidence of post-operative cerebrospinal fluid leak was 10.8 per cent. Seventy-five per cent of patients who had a post-operative cerebrospinal fluid leak underwent a transclival approach (p < 0.05). All patients with clival pathology who underwent an intradural dissection had a post-operative cerebrospinal fluid leak (p < 0.05).
Post-operative cerebrospinal fluid leak rates after the extended endoscopic approach have improved significantly after advancements including the vascularised nasoseptal flap. Despite this, transclival approaches continue to pose much difficulty. Further investigation is necessary to develop technical improvements that can meet the unique challenges associated with this region.
We studied the associations between early postnatal growth gains and neuropsychological outcome in very preterm-born children. Specifically, we wished to establish whether relationships exist between gains in head circumference (relative to gains in body-weight or length), from birth to hospital discharge, and intellectual, language, or motor, performance at preschool age. We used data from 127 preschoolers, born <33 weeks, all graduates of the William Beaumont Hospital Neonatal Intensive-Care Unit (NICU) in Royal Oak, MI. Cognitive, motor, and language outcomes were evaluated using the Wechsler Preschool and Primary Scales of Intelligence-Revised, Peabody Developmental Scales – 2nd Edition, and the Preschool Language Scale – 3rd Edition, respectively. Differences between Z-scores at birth and hospital discharge, calculated for three anthropometric measures (head circumference, weight, length), were variables of interest in separate simultaneous multiple regression procedures. We statistically adjusted for sex, socioeconomic status, birth weight, length of hospitalization, perinatal complications, and intrauterine growth. Examination of the relationships between anthropometric indices and outcome measures revealed a significant association between NICU head growth and global intelligence, with the Z-difference score for head circumference accounting for a unique portion of the variance in global intelligence (ηp2 =.04). Early postnatal head growth is significantly associated with neuropsychological outcome in very preterm-born preschoolers. To conclude, despite its relative brevity, NICU stay, often overlapping with the end of 2nd and with the 3rd trimester of pregnancy, appears to be a sensitive developmental period for brain substrates underlying neuropsychological functions. (JINS, 2015, 21, 126–136)
The paper describes a process which allows a vertical circular cylinder subject to plane monochromatic surface gravity waves to appear invisible to the far-field observer. This is achieved by surrounding the cylinder with an annular region of variable bathymetry. Two approaches are taken to investigate this effect. First a mild-slope approximation is applied to the governing linearised three-dimensional water wave equations to formulate a depth-averaged two-dimensional wave equation with varying wavenumber over the variable bathmetry. This is then solved by formulating a domain integral equation, solved numerically by discretisation. For a given set of geometrical and wave parameters, the bathymetry is selected by a numerical optimisation process and it is shown that the scattering cross-section is reduced towards zero with increasing refinement of the bathymetry. A fully three-dimensional boundary-element method, based on the WAMIT solver (see www.wamit.com) but adapted here to allow for depressions in the bed, is used to assess the accuracy of the mild-slope results and then further numerically optimise the bathymetry towards a cloaking structure. Numerical results provide strong evidence that perfect cloaking is possible for the fully three-dimensional problem. One practical application of the results is that cloaking implies a reduced mean drift force on the cylinder.