Young’s Modulus and Residual Stresses of Oxide-Free Wire Arc Sprayed Copper Coatings

Conventional thermal spraying processes are almost exclusively carried out in an air atmosphere, resulting in the oxidation of the particle surfaces and interfaces within the coating and between the substrate and coating. Furthermore, the initial process of surface activation conventionally takes place in an air atmosphere, preventing an oxide-free interfacial transition. Consequently, the application of spraying materials with high oxygen affinity represents a major challenge. To overcome these issues, the present study utilized silane-doped inert gases to create an environment in which the oxygen concentration was equivalent to the residual oxygen content in an extreme high vacuum. By transferring the corundum blasting and coating process (wire arc spraying) to this environment, materials with a high oxygen affinity can be applied without oxidation occurring. For industrial use, this is an interesting prospect, e.g., for repair coatings, as the homogeneity of the composite is improved by a non-oxidized coating. Using the example of arc-sprayed copper coatings, the microstructure and mechanical properties of the coatings were analysed. The results showed that the oxide-free, wire arc sprayed copper coatings exhibited an improved wetting behaviour resulting in a significant reduction of the coating porosity. Moreover, the improved wetting behaviour and led to an increase in the bonding rate and apparent Young’s modulus. Contrary to expectations, the residual stresses decrease although relaxation mechanisms should be inhibited, and possible reasons for this are discussed in the paper

Characterization of the tribologically relevant cover layers formed on copper in oxygen and oxygen-free conditions

Engineering in vacuum or under a protective atmosphere permits the production of materials, wherever the absence of oxygen is an essential demand for a successful processing. However, very few studies have provided quantitative evidence of the effect of oxidized surfaces to tribological properties. In the current study on 99.99% pure copper, it is revealed that tribo-oxidation and the resulting increased abrasive wear can be suppressed by processing in an extreme high vacuum (XHV) adequate environment. The XHV adequate atmosphere was realized by using a silane-doped shielding gas (1.5 vol% SiH4 in argon). To analyse the influence of the ambient atmosphere on the tribological and mechanical properties, a ball—disk tribometer and a nanoindenter were used in air, argon, and silane-doped argon atmosphere for temperatures up to 800 °C. Resistance measurements of the resulting coatings were carried out. To characterize the microstructures and the chemical compositions of the samples, the scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) were used. The investigations have revealed a formation of η-Cu3Si in silane-doped atmosphere at 300 °C, as well as various intermediate stages of copper silicides. At temperatures above 300 °C, the formation of γ-Cu5Si were detected. The formation was linked to an increase in hardness from 1.95 to 5.44 GPa, while the Young’s modulus increased by 46% to 178 GPa, with the significant reduction of the wear volume by a factor of 4.5 and the suppression of further oxidation and susceptibility of chemical wear. In addition, the relevant diffusion processes were identified using molecular dynamics (MD) simulations. [Figure not available: see fulltext.]

A large scale hearing loss screen reveals an extensive unexplored genetic landscape for auditory dysfunction

The developmental and physiological complexity of the auditory system is likely reflected in the underlying set of genes involved in auditory function. In humans, over 150 non-syndromic loci have been identified, and there are more than 400 human genetic syndromes with a hearing loss component. Over 100 non-syndromic hearing loss genes have been identified in mouse and human, but we remain ignorant of the full extent of the genetic landscape involved in auditory dysfunction. As part of the International Mouse Phenotyping Consortium, we undertook a hearing loss screen in a cohort of 3006 mouse knockout strains. In total, we identify 67 candidate hearing loss genes. We detect known hearing loss genes, but the vast majority, 52, of the candidate genes were novel. Our analysis reveals a large and unexplored genetic landscape involved with auditory function

Height, selected genetic markers and prostate cancer risk:Results from the PRACTICAL consortium

Background: Evidence on height and prostate cancer risk is mixed, however, recent studies with large data sets support a possible role for its association with the risk of aggressive prostate cancer. Methods: We analysed data from the PRACTICAL consortium consisting of 6207 prostate cancer cases and 6016 controls and a subset of high grade cases (2480 cases). We explored height, polymorphisms in genes related to growth processes as main effects and their possible interactions. Results: The results suggest that height is associated with high-grade prostate cancer risk. Men with height 4180cm are at a 22% increased risk as compared to men with height o173cm (OR 1.22, 95% CI 1.01–1.48). Genetic variants in the growth pathway gene showed an association with prostate cancer risk. The aggregate scores of the selected variants identified a significantly increased risk of overall prostate cancer and high-grade prostate cancer by 13% and 15%, respectively, in the highest score group as compared to lowest score group. Conclusions: There was no evidence of gene-environment interaction between height and the selected candidate SNPs. Our findings suggest a role of height in high-grade prostate cancer. The effect of genetic variants in the genes related to growth is seen in all cases and high-grade prostate cancer. There is no interaction between these two exposures.</p

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Atlas of prostate cancer heritability in European and African-American men pinpoints tissue-specific regulation

Although genome-wide association studies have identified over 100 risk loci that explain ∼33% of familial risk for prostate cancer (PrCa), their functional effects on risk remain largely unknown. Here we use genotype data from 59,089 men of European and African American ancestries combined with cell-type-specific epigenetic data to build a genomic atlas of single-nucleotide polymorphism (SNP) heritability in PrCa. We find significant differences in heritability between variants in prostate-relevant epigenetic marks defined in normal versus tumour tissue as well as between tissue and cell lines. The majority of SNP heritability lies in regions marked by H3k27 acetylation in prostate adenoc7arcinoma cell line (LNCaP) or by DNaseI hypersensitive sites in cancer cell lines. We find a high degree of similarity between European and African American ancestries suggesting a similar genetic architecture from common variation underlying PrCa risk. Our findings showcase the power of integrating functional annotation with genetic data to understand the genetic basis of PrCa

Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes

Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues

Daily physical activity, functional capacity and quality of life in patients with COPD

In the therapy of chronic obstructive pulmonary disease (COPD), it is a major goal to improve health-related quality of life (HRQOL). Patients with COPD often suffer from exertional dyspnea and adopt a sedentary lifestyle, which could be associated with poorer HRQOL. The aim of this study was to investigate the independent association of objectively measured daily physical activity and functional capacity with HRQOL in patients with COPD.; In this cross-sectional study conducted at the University Hospital Basel, Switzerland, 87 stable patients (58.6% male, mean age: 67.3 ± 9.6 yrs) with COPD in GOLD grades I (n = 23), II (n = 46), III (n = 12) and IV (n = 6) were investigated. To assess HRQOL, the COPD assessment test (CAT) was completed. Patients performed spirometry and 6-min walk test. Physical activity was measured by the SenseWear Mini Armband on 7 consecutive days. By performing a multiple linear regression analysis, independent predictors of CAT score were identified.; Age (β = -0.39, p = 0.001), average daily steps (β = -0.31, p = 0.033) and 6-min walk distance (β = -0.32, p = 0.019) were found to be independent predictors of CAT score, whereas physical activity duration above 3 METs (p = 0.498) and forced expiratory volume in 1 s in% of predicted (p = 0.364) showed no significant association.; This study showed that average daily steps and functional capacity are independent determinants of HRQOL in patients with COPD. This emphasizes the importance to remain active and mobile, which is associated with better HRQOL

Differences in classification of COPD patients into risk groups A-D: a cross-sectional study

The Global Initiative for Chronic Obstructive Lung Disease proposed in 2011 a new system to classify chronic obstructive pulmonary disease (COPD) patients into risk groups A-D, which considers symptoms and future exacerbation risk to grade disease severity. The aim of this study was to investigate the agreement between COPD risk group classifications using COPD assessment test (CAT) or modified Medical Research Council (mMRC) and severity grades or past-year exacerbations. Furthermore, physical activity across risk groups was examined.; 87 patients with stable COPD were classified into risk groups A-D. CAT and mMRC were completed. Severity grades I-IV were determined using spirometry and the number of past-year exacerbations was recorded. To test the interrater agreement, Cohen's Kappa was calculated. Daily physical activity was measured by the SenseWear Mini armband.; Using CAT, 65.5% of patients were in high-symptom groups (B and D). With mMRC, only 37.9% were in B and D. Using severity grades, 20.7% of patients were in high-exacerbation risk groups (C and D). With past-year exacerbations, 9.2% were in C and D. Interrater agreement between CAT and mMRC (κ = 0.21) and between severity grades and past-year exacerbations (κ = 0.31) was fair. Daily steps were reduced in risk groups B and C + D compared to A (p &lt; 0.01), using either classification.; When classifying COPD patients into risk groups A-D, the use of CAT or mMRC and severity grades or past-year exacerbations does not provide equal results. Daily steps decreased with increasing COPD risk groups

Sleep problems and work injury types : a study of 180 patients in a Swiss emergency department

INTRODUCTION: Sleep problems present a risk for work injuries and are a major occupational health concern worldwide. Knowledge about the influence of sleep problems on work injury patterns is limited. Therefore, the aim of this study was to identify potential associations between different types of work injuries and sleep quality, sleep duration, and daytime sleepiness. METHODS: In this hospital-based study, 180 male and female patients with work injuries were recruited at the Emergency Department of the University Hospital Basel, Switzerland, from December 1st 2009 to June 30th 2011. The data on work injury characteristics, sleep problems, and potential confounders, such as demographic, health, lifestyle, occupational and environmental factors, were collected. Multivariable logistic regression analyses were performed to investigate the relationship between sleep problems and various types of work injury. RESULTS: Each dimension of sleep problems - sleep quality, sleep duration and daytime sleepiness - was a significant risk factor for at least one type of work injury. The strongest association was found for musculoskeletal injuries and falls with short sleep duration (odds ratio [OR] 5.41, 95% confidence interval [CI] 1.81-16.22). The standardised scores of the Pittsburgh sleep quality index (PSQI) and the Epworth sleepiness scale (ESS) did not discriminate between injury types. CONCLUSION: Employees with sleep problems were more likely to suffer from certain types of work injuries. This should be considered by employers monitoring work injuries and implementing prevention measures in the company's health and safety management