Sire Breed, Litter Size, and Environment Influence Genetic Potential for Lamb Growth When Using Sire Breeding Values.

Lamb growth can be optimised with genetic selection using sire Australian sheep breeding values, however, breeding value expression has been shown to be reduced with poor nutrition. It was therefore hypothesised that the genetic potential for lamb growth would also be reduced, where production factors such as multiple births limit growth. Live weights at birth, weaning, and post-weaning were collected from more than 18,000 lambs produced over five years and eight locations of the Sheep Cooperative Research Centre Information Nucleus Flock experiment, and the impact of environment, production factors, and genotype was determined using mixed effects regression. The genetic potential for lamb growth was moderated by environment, multiple births, and sire type (p < 0.05). Twin lambs achieved 76% of the expected weight gain at weaning and 58% post-weaning. For triplet lambs weight gains were drastically less at approximately 30% of the expected gain at the same time points. Lambs born to maternal sires consistently had the poorest response to genetic selection, achieving approximately half the expected weight gain. Hence, producers need to temper expectations for growth based on genetic selection, or employ mitigation strategies such as precision feeding, the use of alternate breeds, or place emphasis on the genetic merit of other desirable traits.

Cervical spine kinematics during machine-based and live scrummaging.

The aim of this study was to compare cervical spine kinematics in rugby union front row players during machine-based and "live" scrummaging. Cervical spine kinematics was measured via electromagnetic tracking of sensors attached to the head and thorax. Joint angles were extracted from each trial at two time points ("bind" prior to engagement and instant of impact) for comparison between scrummaging conditions. The effect of scrummaging condition on kinematics was evaluated using a mixed effects model and estimations were based on a Bayesian framework. With differences ranging from 38° to 50°, the results show that the cervical spine is consistently more flexed when scrummaging against opponents than against a scrum machine. In contrast, there are little differences in the excursion of lateral-flexion (range 5-8°) and axial rotation (7°) between the two conditions. The findings from this study provide clear information on motion patterns in different scrum formations, and suggest that the current design of scrum machines may not promote the same pattern of movement that occurs in live scrums. The results highlight that findings from previous studies that have investigated kinematics during machine-based scrummaging may not be generalisable to a competitive scrummaging context.

Exploring the Sensory Profiles of Children on the Autism Spectrum Using the Short Sensory Profile-2 (SSP-2).

The aim of this study was to identify sensory subtypes in children on the autism spectrum using the Short Sensory Profile-2 (SSP-2). Caregivers of children on the autism spectrum aged 4-11 years (n = 271) completed the SSP-2. Analysis using Dirichlet process mixture model identified a two-cluster model which provided the best solution to subtype sensory responses. Two distinct subtypes were identified: Uniformly elevated (67%) with high scores across all quadrants and Raised avoiding and sensitivity (33%) with raised scores in the avoiding and sensitivity quadrants. There were no differences between subtypes based on chronological age and autism characteristics measured using the social communication questionnaire (total score). Based on the SSP-2, children were reported to experience differences in responses to sensory input, in particular in the area of sensitivity and avoiding.

How Does Diet Change with A Diagnosis of Diabetes? Protocol of the 3D Longitudinal Study.

Diet quality influences glycemic control in people with type 2 diabetes (T2D), impacting their risk of complications. While there are many cross-sectional studies of diet and diabetes, there is little understanding of the extent to which people with T2D change their diet after diagnosis and of the factors that impact those changes. This paper describes the rationale for and design of the 3D longitudinal Study which aims to: (i) describe diet quality changes in the 12 months following T2D diagnosis, (ii) identify the demographic, physical and psychosocial predictors of sustained improvements in diet quality and glycemic control, and (iii) identify associations between glycemic control and diet quality in the 12 months following diagnosis. This cohort study will recruit adults registered with the Australian National Diabetes Services Scheme who have been recently diagnosed with T2D. Participants will be involved in five purposefully developed telephone surveys, conducted at 3 monthly intervals over a 12-month period. Diet quality will be determined using a 24-h dietary recall at each data collection point and the data will be scored using the Dietary Approaches to Stop Hypertension (DASH) diet-quality tool. This study is the first dedicated to observing how people newly diagnosed with T2D change their diet quality over time and the predictors of sustained improvements in diet and glycemic control.

Determinants of medication adherence in older people with dementia from the caregivers' perspective.

ABSTRACTBackground:Adherence to treatment is a primary determinant of treatment success. Caregiver support can influence medication adherence in people with cognitive impairment. This study sought to characterize medication adherence in older people with dementia from the caregivers' perspective, and to identify influencing factors. METHODS: Caregivers caring for a person with dementia and living in the community were eligible to complete the survey. Bayesian profile regression was applied to identify determinants of medication adherence measured using the Adherence to Refills and Medication Scale. RESULTS: Out of the 320 caregivers who participated in the survey, Bayesian profile regression on 221 participants identified two groups: Profile 1 (55 caregivers) with a mean adherence rate of 0.69 (80% Credible Interval (CrI): 0.61-0.77), and Profile 2 (166 caregivers) with a mean adherence rate of 0.80 (80% CrI: 0.77-0.84). Caregivers in Profile 1 were characterized with below data average scores for the following: cognitive functioning, commitment or intention, self-efficacy, and health knowledge, which were all above the data average in Profile 2, except for health knowledge. Caregivers in Profile 1 had a greater proportion of care recipients taking more than five medications and with late-stage dementia. Trade, technical, or vocational training was more common among the caregivers in Profile 1. Profile 2 caregivers had a better patient-provider relationship and less medical problems. CONCLUSIONS: Bayesian profile regression was useful in understanding caregiver factors that influence medication adherence. Tailored interventions to the determinants of medication adherence can guide the development of evidence-based interventions.

Non-significant p-values? Strategies to understand and better determine the importance of effects and interactions in logistic regression.

In the context of generalized linear models (GLMs), interactions are automatically induced on the natural scale of the data. The conventional approach to measuring effects in GLMs based on significance testing (e.g. the Wald test or using deviance to assess model fit) is not always appropriate. The objective of this paper is to demonstrate the limitations of these conventional approaches and to explore alternative strategies for determining the importance of effects. The paper compares four approaches to determining the importance of effects in the GLM using 1) the Wald statistic, 2) change in deviance (model fitting criteria), 3) Bayesian GLM using vaguely informative priors and 4) Bayesian Model Averaging analysis. The main points in this paper are illustrated using an example study, which examines the risk factors for cyber abuse victimization, and are further examined using a simulation study. Analysis of our example dataset shows that, in terms of a logistic GLM, the conventional methods using the Wald test and the change in deviance can produce results that are difficult to interpret; Bayesian analysis of GLM is a suitable alternative, which is enhanced with prior knowledge about the direction of the effects; and Bayesian Model Averaging (BMA) is especially suited for new areas of research, particularly in the absence of theory. We recommend that social scientists consider including BMA in their standard toolbox for analysis of GLMs.

Using Bayesian methodology to explore the profile of mental health and well-being in 646 mothers of children with 13 rare genetic syndromes in relation to mothers of children with autism.

BACKGROUND: It is well documented that mothers of children with intellectual disabilities or autism experience elevated stress, with mental health compromised. However, comparatively little is known about mothers of children with rare genetic syndromes. This study describes mental health and well-being in mothers of children with 13 rare genetic syndromes and contrasts the results with mothers of children with autism. METHODS: Mothers of children with 13 genetic syndromes (n = 646; Angelman, Cornelia de Lange, Down, Fragile-X, Phelan McDermid, Prader-Willi, Rett, Rubenstein Taybi, Smith Magenis, Soto, Tuberous Sclerosis Complex, 1p36 deletion and 8p23 deletion syndromes) and mothers of children with autism (n = 66) completed measures of positive mental health, stress and depression. Using Bayesian methodology, the influence of syndrome, child ability, and mother and child age were explored in relation to each outcome. Bayesian Model Averaging was used to explore maternal depression, positive gain and positive affect, and maternal stress was tested using an ordinal probit regression model. RESULTS: Different child and mother factors influenced different aspects of mental well-being, and critically, the importance of these factors differed between syndromes. Maternal depression was influenced by child ability in only four syndromes, with the other syndromes reporting elevated or lower levels of maternal depression regardless of child factors. Maternal stress showed a more complex pattern of interaction with child ability, and for some groups, child age. Within positive mental health, mother and child age were more influential than child ability. Some syndromes reported comparable levels of depression (SMS, 1p36, CdLS) and stress (SMS, AS) to mothers of children with autism. CONCLUSIONS: Bayesian methodology was used in a novel manner to explore factors that explain variability in mental health amongst mothers of children with rare genetic disorders. Significant proportions of mothers of children with specific genetic syndromes experienced levels of depression and stress similar to those reported by mothers of children with autism. Identifying such high-risk mothers allows for potential early intervention and the implementation of support structures.

D-cycloserine-augmented one-session treatment of specific phobias in children and adolescents.

BACKGROUND: D-Cycloserine has potential to enhance exposure therapy outcomes. The current study presents a preliminary randomized, placebo-controlled double-blind pilot trial of DCS-augmented one-session treatment (OST) for youth (7-14 years) with specific phobia. A secondary aim of this pilot study was to explore the effects of youth age and within-session fear reduction as potential moderators of DCS outcomes in order to generate hypotheses for a larger trial. It was hypothesized that DCS would be associated with greater improvements than placebo, that children (7-10 years) would have greater benefits than adolescents (11-14 years), and that DCS effects would be stronger for participants with the greater within-session fear reduction during the OST. METHODS: Thirty-five children and adolescents were randomized to either OST combined with DCS (n = 17), or OST combined with placebo (PBO; n = 18) and assessed at 1 week, 1 month, and 3 month following treatment. RESULTS: There were no significant pre- to post-treatment or follow-up benefits of DCS relative to placebo. Secondary analyses of age indicated that relative to PBO, DCS was associated with greater improvements for children (but not adolescents) on measures of severity at 1-month follow-up. Children in the DCS condition also showed significantly greater improvement to 1 month on global functioning relative to other groups. Conversely, adolescents had significant post-treatment benefits in the PBO condition on symptom severity measures relative to DCS, and adolescents in the DCS condition had significantly poorer functioning at 3 months relative to all other groups. Finally, there was a trend for within-session fear reduction to be associated with moderating effects of DCS, whereby greater reduction in fear was associated with greater functioning at one-month follow-up for children who received DCS, relative to PBO. LIMITATIONS: The study sample was small and therefore conclusions are tentative and require replication. CONCLUSIONS: Age and within-session fear reduction may be important moderators of DCS-augmented one-session exposure therapy, which requires testing in a fully powered randomized controlled trial.

Bayesian modeling predicts age and sex are not required for accurate stature estimation from femoral length.

Despite the recognized flaws in applying traditional stature estimation equations such as those of Trotter and Gleser (1952) [5] to a contemporary population, there are currently no available alternatives for stature estimation in Australia that address these limitations. Post mortem computed tomography (PMCT) DICOM scans of the left and right femora were acquired from 76 Australian deceased individuals aged 17-76 years for metric analysis. Femoral bicondylar length, femoral epicondylar breadth and anterior-posterior (AP) diameter, medial-lateral (ML) diameter, circumference and cortical area at the femoral midshaft were measured on three-dimensional (3D) models to build statistical models for estimating stature. In addition, Australian individuals aged 16-63 years (n=111) were measured in standing and supine positions to aid in the adjustment of supine stature of deceased individuals utilized in this study to standing stature. The results of this preliminary evaluation strongly indicate that the optimal model for estimating stature includes bicondylar femoral length and epicondylar breadth, that the effect of sex as an independent variable is very low, and there is limited practical benefit in including age in the estimation of stature. Our study indicates that the Australian population sampled represents a small yet significant shift in stature from the original Trotter and Gleser sample. Additionally, in the case of fragmentary remains, it was found that epicondylar breadth and AP diameter had the highest probability of accurate stature estimation in the absence of bicondylar femoral length. As stature forms a significant component of a biological profile and therefore aids in the personal identification of human remains, it is important that forensic anthropologists utilize the most accurate methodologies available. Stature estimation of Australian individuals is therefore achieved with higher accuracy through utilizing the femoral equations proposed in this study.

Apophyseal Ossification of the Iliac Crest in Forensic Age Estimation: Computed Tomography Standards for Modern Australian Subadults.

This study contrasts the ontogeny of the iliac crest apophysis using conventional radiography and multislice computed tomography (MSCT), providing probabilistic information for age estimation of modern Australian subadults. Retrospective abdominopelvic MSCT data acquired from 524 Australian individuals aged 7-25 and surveillance radiographs of adolescent idiopathic scoliosis patients included in the Paediatric Spine Research Group Progression Study (n = 531) were assessed. Ossification scoring of pseudo-radiographs and three-dimensional (3D) volume-rendered reconstructions using Risser (1958) quantitative descriptors indicate discrepancies in age estimates, stage allocation, and conflicting morphological progression. To mitigate visualization limitations associated with two-dimensional radiographs, we provide and validate a modified 3D-MSCT scoring tier of ossification, demonstrating complete fusion between 17.3-19.2 and 17.1-20.1 years in males and females. Legal demarcation for doli incapax presumption and age of majority (18 years) can be achieved using probability estimates from a fitted cumulative probit model for apophyseal fusion using the recalibrated standards.