The geochemistry and mineralogy of some ferromanganese oxides and associated deposits from the Indian and Atlantic Oceans

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Measurement of strain evolution in overloaded roller bearings using time-of-flight neutron diffraction

Neutron diffraction is an established method for non-destructively characterising residual stress or observing in situ strain during external stimuli. Neutron based stroboscopic techniques have previously been introduced for measuring strains undergoing cyclic processes but have not been used for tribological applications. This work presents a novel approach for measuring the evolution of radial strain in a rotating bearing through part of the component's lifetime. A cylindrical roller bearing was pre-overloaded to increase the probability of damage within a reasonable experimental time and to help develop further understanding of the influence such events have on bearing life, notably for the application of wind turbine gearbox bearing failure. The stroboscopic neutron diffraction technique was successful in measuring time-resolved contact strain, with a significant increase in compressive radial strain being observed after a suspected failure had been detected using condition monitoring techniques, implemented for validating damage propagation. Cyclic contact strains associated with rolling contact fatigue were also evaluated using neutron diffraction

Characterisation of the microbiome along the gastrointestinal tract of growing turkeys

The turkey microbiome is largely understudied, despite its relationship with bird health and growth, and the prevalence of human pathogens such as Campylobacter spp. In this study we investigated the microbiome within the small intestine (SI), caeca (C), large intestine (LI) and cloaca (CL) of turkeys at 6, 10 and 16 weeks of age. Eight turkeys were dissected within each age category and the contents of the SI, C, LI and CL were harvested. 16S rDNA based QPCR was performed on all samples and samples for the 4 locations within 3 birds/age group were sequenced using ion torrent-based sequencing of the 16S rDNA. Sequencing data showed on a genus level, an abundance of Lactobacillus, Streptococcus and Clostridium XI (38.2, 28.1 and 13.0% respectively) irrespective of location and age. The caeca exhibited the greatest microbiome diversity throughout the development of the turkey. PICRUSt data predicted an array of bacterial function, with most differences being apparent in the caeca of the turkeys as they matured. QPCR revealed that the caeca within 10 week old birds, contained the most Campylobacter spp. Understanding the microbial ecology of the turkey gastrointestinal tract is essential in terms of understanding production efficiency and in order to develop novel strategies for targeting Campylobacter spppublishersversionPeer reviewe

Activated Met Signalling in the Developing Mouse Heart Leads to Cardiac Disease

BACKGROUND: The Hepatocyte Growth Factor (HGF) is a pleiotropic cytokine involved in many physiological processes, including skeletal muscle, placenta and liver development. Little is known about its role and that of Met tyrosine kinase receptor in cardiac development. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we generated two transgenic mice with cardiac-specific, tetracycline-suppressible expression of either Hepatocyte Growth Factor (HGF) or the constitutively activated Tpr-Met kinase to explore: i) the effect of stimulation of the endogenous Met receptor by autocrine production of HGF and ii) the consequence of sustained activation of Met signalling in the heart. We first showed that Met is present in the neonatal cardiomyocytes and is responsive to exogenous HGF. Exogenous HGF starting from prenatal stage enhanced cardiac proliferation and reduced sarcomeric proteins and Connexin43 (Cx43) in newborn mice. As adults, these transgenics developed systolic contractile dysfunction. Conversely, prenatal Tpr-Met expression was lethal after birth. Inducing Tpr-Met expression during postnatal life caused early-onset heart failure, characterized by decreased Cx43, upregulation of fetal genes and hypertrophy. CONCLUSIONS/SIGNIFICANCE: Taken together, our data show that excessive activation of the HGF/Met system in development may result in cardiac damage and suggest that Met signalling may be implicated in the pathogenesis of cardiac disease

The Val158Met COMT polymorphism is a modifier of the age at onset in Parkinson's disease with a sexual dimorphism

The catechol-O-methyltranferase (COMT) is one of the main enzymes that metabolise dopamine in the brain. The Val158Met polymorphism in the COMT gene (rs4680) causes a trimodal distribution of high (Val/Val), intermediate (Val/Met) and low (Met/Met) enzyme activity. We tested whether the Val158Met polymorphism is a modifier of the age at onset (AAO) in Parkinson's disease (PD). The rs4680 was genotyped in a total of 16 609 subjects from five independent cohorts of European and North American origin (5886 patients with PD and 10 723 healthy controls). The multivariate analysis for comparing PD and control groups was based on a stepwise logistic regression, with gender, age and cohort origin included in the initial model. The multivariate analysis of the AAO was a mixed linear model, with COMT genotype and gender considered as fixed effects and cohort and cohort-gender interaction as random effects. COMT genotype was coded as a quantitative variable, assuming a codominant genetic effect. The distribution of the COMT polymorphism was not significantly different in patients and controls (p=0.22). The Val allele had a significant effect on the AAO with a younger AAO in patients with the Val/Val (57.1±13.9, p=0.03) than the Val/Met (57.4±13.9) and the Met/Met genotypes (58.3±13.5). The difference was greater in men (1.9 years between Val/Val and Met/Met, p=0.007) than in women (0.2 years, p=0.81). Thus, the Val158Met COMT polymorphism is not associated with PD in the Caucasian population but acts as a modifier of the AAO in PD with a sexual dimorphism: the Val allele is associated with a younger AAO in men with idiopathic PD

A Two-Stage Meta-Analysis Identifies Several New Loci for Parkinson's Disease

A previous genome-wide association (GWA) meta-analysis of 12,386 PD cases and 21,026 controls conducted by the International Parkinson's Disease Genomics Consortium (IPDGC) discovered or confirmed 11 Parkinson's disease (PD) loci. This first analysis of the two-stage IPDGC study focused on the set of loci that passed genome-wide significance in the first stage GWA scan. However, the second stage genotyping array, the ImmunoChip, included a larger set of 1,920 SNPs selected on the basis of the GWA analysis. Here, we analyzed this set of 1,920 SNPs, and we identified five additional PD risk loci (combined p<5x10(-10), PARK16/1q32, STX1B/16p11, FGF20/8p22, STBD1/4q21, and GPNMB/7p15). Two of these five loci have been suggested by previous association studies (PARK16/1q32, FGF20/8p22), and this study provides further support for these findings. Using a dataset of post-mortem brain samples assayed for gene expression (n = 399) and methylation (n = 292), we identified methylation and expression changes associated with PD risk variants in PARK16/1q32, GPNMB/7p15, and STX1B/16p11 loci, hence suggesting potential molecular mechanisms and candidate genes at these risk loci

In Search of a Trade Mark: Search Practices and Bureaucratic Poetics

Trade marks have been understood as quintessential ‘bureaucratic properties’. This article suggests that the making of trade marks has been historically influenced by bureaucratic practices of search and classification, which in turn were affected by the possibilities and limits of spatial organisation and technological means of access and storage. It shows how the organisation of access and retrieval did not only condition the possibility of conceiving new trade marks, but also served to delineate their intangible proprietary boundaries. Thereby they framed the very meaning of a trade mark. By advancing a historical analysis that is sensitive to shifts, both in actual materiality and in the administrative routines of trade mark law, the article highlights the legal form of trade mark as inherently social and materially shaped. We propose a historical understanding of trade mark law that regards legal practice and bureaucratic routines as being co-constitutive of the very legal object itself

Performance and nutrient utilisation of dairy cows offered silages produced from three successive harvests of either a red clover–perennial ryegrass sward or a perennial ryegrass sward

The need to reduce reliance on imported protein feeds within the UK and Ireland has stimulated interest in locally grown forage legume crops, including red clover (Trifolium pratense L.). This 13-wk study examined the performance of 28 dairy cows offered silages produced from three successive harvests (H) of either a pure grass sward (GS) receiving 315 kg N/ha per annum or a red clover–perennial ryegrass sward (RCGS) receiving 22 kg N/ha per annum. The crops of H1, H2 and H3 were wilted for 48, 72 and 72 h, respectively. Silages from H1, H2 and H3 were offered for 5, 5 and 3 wk, respectively, with cows supplemented with 8.0 kg concentrate/d throughout the experiment. Digestibility of DM and the effectively degradable protein content were lower, while protein degradability was higher, for RCGS than for GS. Silage DM intakes (DMIs) were higher for RCGS than for GS at H1 and H2, with no differences at H3. Milk yield was higher with RCGS than with GS at H3, with no differences at H1 and H2. Milk fat and milk protein contents were lower with RCGS than with GS at H3 but did not differ at H1 and H2. Faecal N/N intake was higher in the RCGS group than in the GS group at H1, with no differences at H2 and H3. Gross energy digestibility was lower for RCGS than for GS at H2. Although cow performance was higher with RCGS treatment, the responses were variable between harvests, largely reflecting the changing proportion of RC in the swards as the season progresse