In this paper two discontinuous Galerkin isogeometric analysis methods are developed and applied to the first-order form of the neutron transport equation with a discrete ordinate (SN) angular ...discretisation. The discontinuous Galerkin projection approach was taken on both an element level and the patch level for a given Non-Uniform Rational B-Spline (NURBS) patch. This paper describes the detailed dispersion analysis that has been used to analyse the numerical stability of both of these schemes. The convergence of the schemes for both smooth and non-smooth solutions was also investigated using the method of manufactured solutions (MMS) for multidimensional problems and a 1D semi-analytical benchmark whose solution contains a strongly discontinuous first derivative. This paper also investigates the challenges posed by strongly curved boundaries at both the NURBS element and patch level with several algorithms developed to deal with such cases. Finally numerical results are presented both for a simple pincell test problem as well as the C5G7 quarter core MOX/UOX small Light Water Reactor (LWR) benchmark problem. These numerical results produced by the isogeometric analysis (IGA) methods are compared and contrasted against linear and quadratic discontinuous Galerkin finite element (DGFEM) SN based methods.
Objective
To evaluate the effect of providing antenatal dietary and lifestyle advice on neonatal anthropometry, and to determine the inter‐observer variability in obtaining anthropometric ...measurements.
Design
Randomised controlled trial.
Setting
Public maternity hospitals across metropolitan Adelaide, South Australia.
Population
Pregnant women with a singleton gestation between 10+0 and 20+0 weeks, and body mass index (BMI) ≥25 kg/m2.
Methods
Women were randomised to either Lifestyle Advice (comprehensive dietary and lifestyle intervention over the course of pregnancy including dietary, exercise and behavioural strategies, delivered by a research dietician and research assistants) or continued Standard Care. Analyses were conducted using intention‐to‐treat principles.
Main outcome measures
Secondary outcome measures for the trial included assessment of infant body composition using body circumference and skinfold thickness measurements (SFTM), percentage body fat, and bio‐impedance analysis of fat‐free mass.
Results
Anthropometric measurements were obtained from 970 neonates (488 Lifestyle Advice Group, and 482 Standard Care Group). In 394 of these neonates (215 Lifestyle Advice Group, and 179 Standard Care Group) bio‐impedance analysis was also obtained. There were no statistically significant differences identified between those neonates born to women receiving Lifestyle Advice and those receiving Standard Care, in terms of body circumference measures, SFTM, percentage body fat, fat mass, or fat‐free mass. The intra‐class correlation coefficient for SFTM was moderate to excellent (0.55–0.88).
Conclusions
Among neonates born to women who are overweight or obese, anthropometric measures of body composition were not modified by an antenatal dietary and lifestyle intervention.
Tweetable
Lifestyle advice in pregnancy does not modify body composition of infants of overweight and obese women.
Tweetable
Lifestyle advice in pregnancy does not modify body composition of infants of overweight and obese women.
Performance, DMI, diet composition, and slaughter data from 9,683 pens of steers and 5,009 pens of heifers that were fed high-concentrate diets for 90 d or more were obtained from 15 feedlots from ...the western United States and Canada. The data set included pen means for more than 3.1 million cattle fed between 1998 and 2004. Performance measurements assessed included ADG, DMI, dietary NE, shrunk initial weight (SIW), and shrunk final weight. Mature final weight (MFW) for cattle in each pen was estimated based on regression of slaughter weight against SIW and ADG across all pens. Equations were developed to standardize performance projections (ADG, MFW, and break-even values) and analyze feedlot cattle close-outs. Generally, as diet NE concentration increased, DMI was decreased but G:F, dressing percentage, and yield grade all increased. Pens of cattle with greater SIW had greater ADG, DMI, and shrunk final weight but a lower G:F and dressing percentage. Dressing percentage and yield grade were correlated positively. Equations of the NRC relating gain to NE intake explained 85 and 80% of the variation in DMI of steers and heifers, respectively, with mean ratios of predicted to observed DMI (DMIratio) at 1.000 ± 0.0506 and 0.974 ± 0.0490. However, a significant (P < 0.001) bias in the NRC estimate of DMI was detected (r² = 0.10 and 0.05, for steers and heifers) between the DMIratio and ADG in which DMIratio increased as ADG increased. This was due to inherent confounding of ADG and MFW in the original NE equation of Lofgreen and Garrett. Based on iterative optimization to minimize the difference between expected and observed DMI, revised equations for retained energy (RE, Mcal/kg) were developed for steers and for heifers: REsteer = 0.0606 x (LW x 478/MFWsteer)⁰.⁷⁵ADG⁰.⁹⁰⁵; REheifer = 0.0618 x (LW x 478/MFWheifer)⁰.⁷⁵ADG⁰.⁹⁰⁵, where LW = mean shrunk live weight. The revised equations decreased the SD of the DMIratio by 5.4% (from 0.0496 to 0.0469) and eliminated the bias in DMIratio that was related to ADG (r² = 0.0006). The similarity between the 2 equations derived for steers and for heifers for estimation of RE from ADG supports the concept that scaling by MFW accounts for energy utilization differences between sexes.
•Numerical method for calculating optimal trace inequality constants for application to interior penalty methods presented.•Can be applied to any elements for which stiffness matrices can be ...calculated, including those with a non-constant Jacobian.•The new method provides sharper bounds than those from the literature when the mapping from the reference element is linear.•Results in a linear system that can be solved 11% faster than methods from the literature for an MMS test case.
In this paper, a new method to numerically calculate the trace inequality constants, which arise in the calculation of penalty parameters for interior penalty discretisations of elliptic operators, is presented. These constants are provably optimal for the inequality of interest. As their calculation is based on the solution of a generalised eigenvalue problem involving the volumetric and face stiffness matrices, the method is applicable to any element type for which these matrices can be calculated, including standard finite elements and the non-uniform rational B-splines of isogeometric analysis. In particular, the presented method does not require the Jacobian of the element to be constant, and so can be applied to a much wider variety of element shapes than are currently available in the literature. Numerical results are presented for a variety of finite element and isogeometric cases. When the Jacobian is constant, it is demonstrated that the new method produces lower penalty parameters than existing methods in the literature in all cases, which translates directly into savings in the solution time of the resulting linear system. When the Jacobian is not constant, it is shown that the naive application of existing approaches can result in penalty parameters that do not guarantee coercivity of the bilinear form, and by extension, the stability of the solution. The method of manufactured solutions is applied to a model reaction-diffusion equation with a range of parameters, and it is found that using penalty parameters based on the new trace inequality constants result in better conditioned linear systems, which can be solved approximately 11% faster than those produced by the methods from the literature.
Since 1988, viroids have been occasionally detected in samples of tomato (Lycopersicon esculentum) originating both in the Netherlands and other countries. Infected plants showed chlorosis, bronzing, ...leaf distortion and growth reduction. Initial diagnosis of these viroids was by return-polyacrylamide gel electrophoresis, which did not allow a further identification. This paper reports the identification of these viroids by reverse transcription-polymerase chain reaction and sequence analysis. Three known viroids of tomato, i.e. Citrus exocortis viroid, Potato spindle tuber viroid and Tomato chlorotic dwarf viroid were identified. In addition, six isolates were identified as Columnea latent viroid, a viroid so far only detected in some ornamental species. Like the isolates previously isolated from ornamental species, the isolates from tomato share genetic characteristics of both the genera Hostuviroid and Pospiviroid. The biological characteristics of all four viroids, especially their potential effects on both potato (Solanum tuberosum) and tomato, stress the need for reconsideration of their phytosanitary risks.
Pale, soft, exudative (PSE) turkey meat is a growing problem for the industry of further processed poultry meat. The low pH condition due to rapid glycolysis while the body temperature is still high ...leads to protein denaturation, causing pale color and reduced water-holding capacity. This condition impacts product yield and quality. These studies were designed to estimate the incidence of PSE broiler meat in a commercial plant and to use response surface methodology to characterize the relationship between pH and lightness (at deboning and at 24 h postmortem), expressible moisture, drip loss, and cook loss. Pale fillets had significantly lower pH, greater L* values at 3 and 24 h postmortem, and higher expressible moisture, drip loss, and cook loss. The lower water-holding capacity of the pale fillets was characteristic of PSE meat. Additionally, L* values were measured on 3,554 boneless broiler breast fillets in a commercial processing line. By using the L* value range (>54) from the pale group of fillets as an indication of paleness, approximately 47% of the 3,554 fillets were pale and could potentially exhibit poor water-holding capacity. These results may not represent the entire industry but indicate that PSE chicken can represent a substantial proportion of commercially processed broiler meat.
We present automatic extraction of local 3D features (L3DF) from ear and face biometrics and their combination at the feature and score levels for robust identification. To the best of our knowledge, ...this paper is the first to present feature level fusion of 3D features extracted from ear and frontal face data. Scores from L3DF based matching are also fused with iterative closest point algorithm based matching using a weighted sum rule. We achieve identification and verification (at 0.001 FAR) rates of 99.0% and 99.4%, respectively, with neutral and 96.8% and 97.1% with non-neutral facial expressions on the largest public databases of 3D ear and face.
► The ear and the face are highly attractive biometric modalities for fusion. ► Two complete and fully automatic ear–face multimodal recognition systems. ► The first feature-level fusion approach combining 3D ear and face features. ► Score-level fusion performs better especially with non-neutral facial expressions.
In this paper a method is presented for the application of energy-dependent spatial meshes applied to the multigroup, second-order, even-parity form of the neutron transport equation using ...Isogeometric Analysis (IGA). The computation of the inter-group regenerative source terms is based on conservative interpolation by Galerkin projection. The use of Non-Uniform Rational B-splines (NURBS) from the original computer-aided design (CAD) model allows for efficient implementation and calculation of the spatial projection operations while avoiding the complications of matching different geometric approximations faced by traditional finite element methods (FEM). The rate-of-convergence was verified using the method of manufactured solutions (MMS) and found to preserve the theoretical rates when interpolating between spatial meshes of different refinements. The scheme's numerical efficiency was then studied using a series of two-energy group pincell test cases where a significant saving in the number of degrees-of-freedom can be found if the energy group with a complex variation in the solution is refined more than an energy group with a simpler solution function. Finally, the method was applied to a heterogeneous, seven-group reactor pincell where the spatial meshes for each energy group were adaptively selected for refinement. It was observed that by refining selected energy groups a reduction in the total number of degrees-of-freedom for the same total L2 error can be obtained.
In this paper a hanging-node, discontinuous Galerkin, isogeometric discretisation of the multigroup, discrete ordinates (SN) equations is presented in which each energy group has its own mesh. The ...equations are discretised using Non-Uniform Rational B-Splines (NURBS), which allows the coarsest mesh to exactly represent the geometry for a wide range of engineering problems of interest; this would not be the case using straight-sided finite elements. Information is transferred between meshes via the construction of a supermesh. This is a non-trivial task for two arbitrary meshes, but is significantly simplified here by deriving every mesh from a common coarsest initial mesh. In order to take full advantage of this flexible discretisation, goal-based error estimators are derived for the multigroup, discrete ordinates equations with both fixed (extraneous) and fission sources, and these estimators are used to drive an adaptive mesh refinement (AMR) procedure. The method is applied to a variety of test cases for both fixed and fission source problems. The error estimators are found to be extremely accurate for linear NURBS discretisations, with degraded performance for quadratic discretisations owing to a reduction in relative accuracy of the “exact” adjoint solution required to calculate the estimators. Nevertheless, the method seems to produce optimal meshes in the AMR process for both linear and quadratic discretisations, and is ≈×100 more accurate than uniform refinement for the same amount of computational effort for a 67 group deep penetration shielding problem.
To evaluate the utility of N as a digestion marker to predict total tract starch digestion, data from 32 metabolism trials involving 147 steers and 637 individual starch digestibility measurements ...were compiled. All trials were conducted at the University of California Desert Research and Extension Center. Total tract starch digestibility was determined from concentrations of starch and chromic oxide in feed and feces. In all trials, the steers were adapted to diets for 10 d followed by 4 d for collection of samples of feces. During collection, fecal samples (approximately 200 g, wet basis) were obtained twice daily. Samples from each steer within each collection period were composited for analysis. Diets contained 46.5 ± 7.4% starch and 1.85 ± 0.20% N. Apparently digestible N as a percentage of diet DM was closely associated (r² = 0.73; P < 0.001) with dietary N concentration. Fecal N concentration (FN, % of DM) explained 35% of the variation in fecal DM excretion (Sy.x = 4.3; P < 0.001). Incorporating FN into the model, starch digestion was estimated as follows: starch digestion, % of intake = 100 {1 - (0.938 -0.497FN + 0.0853FN²) FS/DS}, where FS is fecal starch concentration (% of DM) and DS is dietary starch concentration (% of DM; r² = 0.94; Sy.x = 0.68; P < 0.001). Fecal starch concentration alone explained 96% of the variation (Sy.x = 0.45; P < 0.001) in total tract starch digestion: starch digestion, % = 99.9 - 0.413FS -0.0104FS². Omitting cases in our data set in which observed total tract starch digestion was less than 95%, the r² between FS and starch digestibility decreased to 0.82 (Sy.x = 0.26; n = 529). However, estimated starch digestion using the equation incorporating FN remained closely associated with the observed starch digestion (r² = 0.90; Sy.x = 0.22; P < 0.001; n = 529). Equations also were developed to predict NEm and NEg concentrations of common feed grains based on starch digestibility and FS. Starch digestion can be accurately predicted based on FS. However, incorporation of FN into the model markedly enhanced the estimates of grain quality and the efficacy of processing when total tract starch digestion exceeded 95%.
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