Surface drag reduction and flow separation control in pelagic vertebrates, with implications for interpreting scale morphologies in fossil taxa

Living in water imposes severe constraints on the evolution of the vertebrate body. As a result of these constraints, numerous extant and extinct aquatic vertebrate groups evolved convergent osteological and soft-tissue adaptations. However, one important suite of adaptations is still poorly understood: dermal cover morphologies and how they influence surface fluid dynamics. This is especially true for fossil aquatic vertebrates where the soft tissue of the dermis is rarely preserved. Recent studies have suggested that the keeled scales of mosasaurids (pelagic lizards that lived during the Late Cretaceous) aided in surface frictional drag reduction in a manner analogous to the riblets on shark placoid scales. However, here we demonstrate that mosasaurid scales were over an order of magnitude too large to have this effect. More likely they increased the frictional drag of the body and may have played a role in controlling flow separation by acting as surface roughness that turbulated the boundary layer. Such a role could have reduced pressure drag and enhanced manoeuvrability. We caution those studying fossil aquatic vertebrates from positing the presence of surface drag reducing morphologies, because as we show herein, to be effective such features need to have a spacing of approximately 0.1?mm or less

Microvascular Disease with Heart Failure with Reduced and Preserved Ejection Fraction in Patients with Type 2 Diabetes

Aims: Identification of patients with type 2 diabetes (T2D) at increased risk of incident heart failure (HF) beyond traditional risk factors such as prior myocardial infarction (MI) might allow selection of patients who would benefit from preventative treatment. Microvascular disease (MiVD) is thought to play a pathophysiological role in the development of HF in T2D; however, its association with new-onset HF with reduced or preserved ejection fraction has not been specifically defined. Methods and results: Patients in the Genetics of Diabetes Audit and Research Tayside Scotland study were linked to echocardiography, prescriptions, and clinical outcomes. In total, 9141 patients with T2D were identified for analysis. Clinical variables and the presence of retinopathy, nephropathy, and neuropathy were assessed. Cumulative incidence was calculated for the association of both individual and the total number of MiVD states and incident HF. Median follow-up was 9.3 years. In total, there were 900 HF events. The presence of any MiVD was independently associated with both HF with reduced ejection fraction (hazard ratio 1.40; 95% confidence interval 1.11–1.76, P = 0.004) and HF with preserved ejection fraction (hazard ratio 1.38; 95% confidence interval 1.10–1.72, P = 0.005), with a stepwise association between the number of MiVD states and risk of incident HF (P for trend &lt;0.001). Similar associations were found in sensitivity analyses limited to patients without a prior MI, and using competing risks analysis. Conclusions: Individuals with T2D and with MiVD are at risk of incident HF independent of a history of prior HF or MI. Patients with MiVD could benefit from screening for HF and individualized therapy with treatments that lower HF risk.</p

Organic-Conventional Dairy Systems Trial in New Zealand: Four Years’ Results

The Organic-Conventional Comparative Dairy Systems trial at Massey University began in August 2001, and the organic farmlet achieved certification in August 2003. The trial is unique because it is the only comparative grassland-based open grazing dairy study in the world. The organic and conventional systems are managed individually according to best practice, and both are intensively monitored for production, animal health, and environmental impacts. The systems remained similar for the first two years, but began to diverge in the third and fourth years. Production has been 10-20% lower on the organic farm, but environmental impacts appear to be less than on the conventional unit, and net incomes would be similar given a 20% price premium for the organic product. Animal health issues have been manageable on the organic farmlet, and not too dissimilar from the conventional farmlet. Full results after four years of the trial will be available and presented at the conference

The impact of phenotype, ethnicity and genotype on progression of Type 2 diabetes mellitus

Aim: To conduct a comprehensive review of studies of glycaemic deterioration in type 2 diabetes and identify the major factors influencing progression.Methods: We conducted a systematic literature search with terms linked to type 2 diabetes progression. All the included studies were summarized based upon the factors associated with diabetes progression and how the diabetes progression was defined.Results: Our search yielded 2785 articles; based on title, abstract and full‐text review, we included 61 studies in the review. We identified seven criteria for diabetes progression: ‘Initiation of insulin’, ‘Initiation of oral antidiabetic drug’, ‘treatment intensification’, ‘antidiabetic therapy failure’, ‘glycaemic deterioration’, ‘decline in beta‐cell function’ and ‘change in insulin dose’. The determinants of diabetes progression were grouped into phenotypic, ethnicity and genotypic factors. Younger age, poorer glycaemia and higher body mass index at diabetes diagnosis were the main phenotypic factors associated with rapid progression. The effect of genotypic factors on progression was assessed using polygenic risk scores (PRS); a PRS constructed from the genetic variants linked to insulin resistance was associated with rapid glycaemic deterioration. The evidence of impact of ethnicity on progression was inconclusive due to the small number of multi‐ethnic studies.Conclusion: We have identified the major determinants of diabetes progression—younger age, higher BMI, higher HbA1c and genetic insulin resistance. The impact of ethnicity is uncertain; there is a clear need for more large‐scale studies of diabetes progression in different ethnic groups

Frequency and preventative interventions for non-suicidal self-injury and suicidal behaviour in primary school-age children : a scoping review protocol

Introduction: Non-suicidal self-injury (NSSI) and suicidal behaviour have been witnessed in children as young as 6–7 years of age, but while there are many reviews of preventative interventions for NSSI and suicide in adolescents, few have explored its prevalence in younger children and the potential impact of preventative interventions at this stage of life. NSSI and suicidal behaviour are an increasing concern in schools but school-based programmes can improve knowledge, attitudes and help-seeking behaviours and help prevent escalation of NSSI and later suicide. This scoping review will aim to explore the nature and extent of the evidence on the magnitude of NSSI and suicidal behaviour in primary school children, and to examine whether there are any primary school-based interventions available for the prevention of this phenomenon in 5 to 11-year-olds. Methods and analysis: A scoping review will be conducted using established methodology by Arksey and O’Malley and the Joanna Briggs Institute. Multiple bibliographic and indexing databases and grey literature will be searched using a combination of text words and index terms relating to NSSI, suicide, primary schools, frequency and intervention. Two reviewers will independently screen eligible studies for study selection and extract relevant data from included studies. A narrative summary of evidence will be conducted for all included studies with results presented in tables and/or diagrams. Inductive content analysis will be used to understand any narrative findings within the included studies. Ethics and dissemination: Ethical approval is not required for this scoping review. The results of this review will be disseminated though publication in a peer-reviewed journal and presented at relevant conferences

Tailored second line therapy in asthmatic children with the arginine-16 genotype

The arginine-16 beta-2 receptor genotype confers increased susceptibility to exacerbations in asthmatic children taking regular long acting beta-2 agonists. We therefore evaluated using montelukast as an alternative to salmeterol as tailored second line asthma controller therapy in children expressing this susceptible genotype. 62 persistent asthmatic children with the homozygous arginine-16 genotype were randomized to receive salmeterol 50ug bid or montelukast 5/10mg od as add on to inhaled fluticasone for 1 year. School absences (the primary outcome) were reduced with montelukast arm compared to salmeterol: difference in score = 0.40 (95%CI 0.07-0.87) p=0.005. Albuterol use was also reduced with montelukast compared with salmeterol: difference in score = 0.47 (95%CI 0.16-0.79) p<0.0001. Greater improvements occurred in both symptom and quality of life scores with montelukast vs salmeterol, while there was no difference in FEV1. Montelukast may be suitable as tailored second line controller therapy instead of salmeterol in asthmatic children expressing the susceptible arginine-16 genotype - moving towards a personalised medicine approach to management

Loss-of-function variants of the filaggrin gene are associated with atopic eczema and associated phenotypes in Swedish families

Recent studies have identified 2 loss-of-function variants, R501X and 2282del4, in the filaggrin gene as predisposing factors in the development of eczema. In this study, representing the first analysis of the variants in a Swedish population, we analysed transmission in 406 multiplex eczema families with mainly adult patients. In accordance with previous studies we found association between the filaggrin gene variants and atopic eczema (p=9.5x10(-8)). The highest odds ratio for the combined alllele, 4.73 (1.98-11.29), p=3.6x10(-8), was found for the subgroup with a severe eczema phenotype, and association was also found with raised allergen-specific IgE, allergic asthma and allergic rhinoconjunctivitis occurring in the context of eczema. Our results support an important role for the filaggrin gene variants R501 X and 2282del4 in the development and severity of atopic eczema and indicate a possible role for the subsequent progression into eczema-associated phenotypes.</p