Material weakening due to corrosion in hardened bearing steels

In rolling and ball bearings, materials are designed to withstand extremely high loads for long operation times. Most bearing steels are hardened steels with high carbon content that typically can function up to the Very High Cycle Fatigue regime (\u3e1010 load cycles). The loads under which this occurs are given by the fatigue limit, which is a parameter that does depend on the strength of the material, but is commonly seen as a fixed parameter Therefore, material weakening is playing an important role when components fail as a result of rolling contact fatigue loading. In this paper, the effects of corrosion and hydrogen generation on the material weakening of hardened ball bearing steels are described. The results of corrosion exposure tests, fatigue tests with corrosion and tests with increased hydrogen levels in steel on mechanical properties will be presented. The role of hydrogen in bearing steel will be discussed on basis of the atomistic processes that play a role in rolling contact fatigue

Ankyrin is the major oxidised protein in erythrocyte membranes from end-stage renal disease patients on chronic haemodialysis and oxidation is decreased by dialysis and vitamin C supplementation

Chronically haemodialysed end-stage renal disease patients are at high risk of morbidity arising from complications of dialysis, the underlying pathology that has led to renal disease and the complex pathology of chronic kidney disease. Anaemia is commonplace and its origins are multifactorial, involving reduced renal erythropoietin production, accumulation of uremic toxins and an increase in erythrocyte fragility. Oxidative damage is a common risk factor in renal disease and its co-morbidities and is known to cause erythrocyte fragility. Therefore, we have investigated the hypothesis that specific erythrocyte membrane proteins are more oxidised in end-stage renal disease patients and that vitamin C supplementation can ameliorate membrane protein oxidation. Eleven patients and 15 control subjects were recruited to the study. Patients were supplemented with 2 × 500 mg vitamin C per day for 4 weeks. Erythrocyte membrane proteins were prepared pre- and post-vitamin C supplementation for determination of protein oxidation. Total protein carbonyls were reduced by vitamin C supplementation but not by dialysis when investigated by enzyme linked immunosorbent assay. Using a western blot to detect oxidised proteins, one protein band, later identified as containing ankyrin, was found to be oxidised in patients but not controls and was reduced significantly by 60% in all patients after dialysis and by 20% after vitamin C treatment pre-dialysis. Ankyrin oxidation analysis may be useful in a stratified medicines approach as a possible marker to identify requirements for intervention in dialysis patients

Venous gas embolism as a predictive tool for improving CNS decompression safety

A key process in the pathophysiological steps leading to decompression sickness (DCS) is the formation of inert gas bubbles. The adverse effects of decompression are still not fully understood, but it seems reasonable to suggest that the formation of venous gas emboli (VGE) and their effects on the endothelium may be the central mechanism leading to central nervous system (CNS) damage. Hence, VGE might also have impact on the long-term health effects of diving. In the present review, we highlight the findings from our laboratory related to the hypothesis that VGE formation is the main mechanism behind serious decompression injuries. In recent studies, we have determined the impact of VGE on endothelial function in both laboratory animals and in humans. We observed that the damage to the endothelium due to VGE was dose dependent, and that the amount of VGE can be affected both by aerobic exercise and exogenous nitric oxide (NO) intervention prior to a dive. We observed that NO reduced VGE during decompression, and pharmacological blocking of NO production increased VGE formation following a dive. The importance of micro-nuclei for the formation of VGE and how it can be possible to manipulate the formation of VGE are discussed together with the effects of VGE on the organism. In the last part of the review we introduce our thoughts for the future, and how the enigma of DCS should be approached

How unstable? Volatility and the genuinely new parties in Eastern Europe

Measuring of party system stability in Eastern Europe during the first decade of democratic elections presents problems. The traditional quantitative measure - volatility - does not distinguish between the dynamics among incumbent parties and the rise of genuinely new ones. I propose a new additional measure - success of genuinely new parties - and compare it to volatility. The subsequent performance of initially successful genuinely new parties is analysed. While volatility has been remarkably high in East European countries, the genuinely new parties have, in general, not been very successful. Instability of party systems in the region stems rather from the inner dynamics of incumbent actors than from the rise of new contenders

How to support child healthcare nurses in sweden to promote healthy lifestyle behaviors from the start of life

Child healthcare (CHC) nurses have a key role in promoting and supporting healthy lifestyle behaviors from a young age. Thus, this study aims to investigate the perspectives of CHC nurses regarding discussing food introduction, physical activity/active play, and screen time with parents; explore facilitators and barriers influencing the discussion of healthy lifestyle behaviors with parents; and explore the perspectives of CHC nurses regarding a complementary program to promote healthy lifestyle behaviors from the start of life. A total of fifteen nurses participated in semi-structured interviews, which were recorded, transcribed verbatim, and analyzed using thematic analysis. There were four themes that were generated: parental needs; facilitators and barriers; parental groups; and future working methods. This study found that CHC nurses have seen an increase in the need for support among today’s parents. Time, the need to tailor information, and confidence to address sensitive topics were perceived as the largest barriers during daily work for the nurses. Furthermore, large variations in parental groups were found. Finally, the CHC nurses displayed a willingness and openness to change and develop current working methods using digital solutions. These solutions could possibly ease the workload and at the same time, support parents to create healthy lifestyle behaviors from the start of their child’s life.</jats:p

Extravascular lung water index: Diagnostic accuracy and relation to lung injury and mortality in patients with shock

INTRODUCTION. The diagnosis of acute lung injury may be more robust if more accurate physiological markers can be identified. Extravascular lung water index (EVLWI) may be useful and has been shown to correlate with respiratory function and mortality in patients with sepsis and ARDS. Whether this applies to a wider population, and which index performs best, are unclear. OBJECTIVES. We hypothesized that EVLWI correlates with respiratory function and mortality in patients with documented systemic inflammation and shock. We investigated EVLW indexed to actual and predicted body weight, and pulmonary blood volume. We investigated the diagnostic accuracy of EVLWI for lung injury. METHODS. In 51 patients with shock and SIRS, EVLWI was measured within 6 h of ICU admission and indexed to actual weight (EVLWI/ABW), predicted body weight (EVLWI/ PBW) and pulmonary blood volume (EVLWI/PBV). Relationships to lung injury and ICUmortality were investigated. Positive and negative likelihood ratios, pre- and post-test odds and ROC curves were calculated. RESULTS. EVLWI was higher among patients with lung injury and was significantly correlated with respiratory parameters. EVLWI/ABW was higher among non-survivors and gave the best positive likelihood ratios for diagnosing ALI/ARDS. In contrast, EVLWI/PBV gave better diagnostic value for severe lung injury according to Murray's LIS criteria. The post-test odds for ALI and ARDS increased threefold when using EVLWI/ABW as a bedside test. The post-test odds of severe lung injury increased eightfold using EVLWI/PBV. EVLWI/ABW and EVLWI/PBV generated the best ROC curves for mortality prediction with a sensitivity of 68% and specificity of 63-72%. CONCLUSIONS. EVLWI was associated with degree of lung injury, regardless of the index used, supporting its usefulness as a bedside indicator for disease severity. EVLWI/PBV and EVLW/ABW gave the best diagnostic accuracies for the diagnosis of lung injury, and generated the bestROCcurves for mortality prediction.EVLWI/ABWwas significantly increased in non-survivors. Further studies are needed to confirm the additional value of EVLWI for the early identification of lung injury