120 research outputs found
Leaded tin bronzes: the effects of casting method on dry sliding behaviour
In metal-to-metal sliding bearing applications, leaded tin bronzes are widely known as materials with excellent seizure resistance. In conditions of boundary or dry lubrication, lead may smear across the sliding surface, preventing surface contact and catastrophic seizure. The aim of this study was to determine the effects of casting method on the dry sliding behaviour of leaded tin bronzes. Continuous cast, centrifugally cast, and sand cast leaded tin bronze samples with varying lead contents were subjected to pin-on-disk- testing. It was found that casting method has a significant effect on the wear behaviour of leaded tin bronzes in dry sliding conditions. With continuous cast samples, the dominant wear mode was rapid, stable microcracking along copper/lead interfacial boundaries. With centrifugally and sand cast samples, wear occurred more slowly and erratically through the formation of transfer layers. The dominant wear mode was found to be connected to the coarseness of the distribution of lead particles in the copper matrix
Multichannel optical sensor for oil film pressure measurement in engine main bearing
An optical sensor has been developed for experimental determination of oil film pressure in journal bearings. The non-intrusive fibre optic sensor is integrated in the sliding surface of the bearing to measure the actual oil film pressure under load without disturbing the actual tribological contact conditions. The sensors with a multichannel system also allowed the use of several optical sensors simultaneously.
Four optical sensors were integrated in a hydrodynamic journal bearing of a large scale diesel engine and the engine tests were carried out with different loads to study the sensor operation in demanding operating conditions. The oil film pressure was successfully measured and the results showed differences in bearing pressure depending on the position of the sensor and on the operating cycle of the cylinders. The optical sensor was capable to measure the oil film pressure in journal bearing with a good sensitivity and repeatability during the tests.  
Oral health indices predict individualised recall interval
Objectives: The individualised recall interval (IRI) is part of the oral health examination. This observational, register-based study aimed to explore how oral health indices DMFT (decayed, missing, filled teeth), DT (decayed teeth), CPI (Community Periodontal Index, maximum value of individual was used) and number of teeth are associated with IRI for adults. Methods: Oral health examination includes an assessment of all oral tissues, diagnosis, a treatment plan and assessment and a determination of the interval before the next assessment. It is called the IRI. This cross-sectional study population included 42,533 adults (age range 18-89 years), who had visited for an oral health examination during 2009, provided by the Helsinki City Social Services and Health Care. The recall interval was categorised into an ordinal scale (0-12, 13-24, 25-36 and 37-60 months) and was modelled using a proportional odds model. ORs less than one indicated a shorter recall interval. Results: Recall interval categories in the study population were 0-12 months (n = 4,569; 11%), 13-24 months (n = 23,732; 56%), 25-36 months (n = 12,049; 28%), and 37-60 months (n = 2,183; 5%). The results of statistical models clearly showed an association between the length of recall intervals and oral health indices. In all models, higher values of DMFT, DT and CPI indicated a shorter recall interval. The number of teeth were not so relevant. The association was not influenced when different combinations of other predictors (age, gender, socioeconomic status, chronic diseases) were included in the model. The severity of periodontitis predicted a short recall interval, for example, in the Model 1, CPI maximum value 4 was OR = 0.35 (95% confidence interval 0.31-0.40). Conclusions: The oral health indices showed a clear association with the length of the IRI. Poor oral health reduced IRI. The indices provide information about the amount of oral health prevention required and are useful to health organisations.Peer reviewe
Systematically missing confounders in individual participant data meta-analysis of observational cohort studies.
One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an exposure and disease either are restricted to cohorts with full confounder information, or use all cohorts but do not fully adjust for confounding. We propose using a bivariate random-effects meta-analysis model to use information from all available cohorts while still adjusting for all the potential confounders. Our method uses both the fully adjusted and the partially adjusted estimated effects in the cohorts with full confounder information, together with an estimate of their within-cohort correlation. The method is applied to estimate the association between fibrinogen level and coronary heart disease incidence using data from 154,012 participants in 31 cohort
Antifascism, the 1956 Revolution and the politics of communist autobiographies in Hungary 1944-2000
This is a postprint of an article whose final and definitive form has been published in Europe-Asia Studies © 2006 University of Glasgow; Europe-Asia Studies is available online at http://www.informaworld.com.Using oral history, this contribution explores the reshaping of individuals' public and private autobiographies in response to different political environments. In particular, it analyses the testimony of those who were communists in Hungary between 1945 and 1956, examining how their experiences of fascism, party membership, the 1956 Revolution and the collapse of communism led them in each case to refashion their life stories. Moreover, it considers how their biographies played varying functions at different points in their lives: to express identification with communism, to articulate resistance and to communicate ambition before 1956; to protect themselves from the state after 1956; and to rehabilitate themselves morally in a society which stigmatised them after 1989.I didn't use this word 'liberation' (felszabadulás), because in 1956 my life really changed. Everybody's lives went through a great change, but mine especially. … I wasn't disgusted with myself that I had called the arrival of the Red Army in 1945 a liberation, but [after 1956] I didn't use it anymore
Changes in LDL Fatty Acid Composition as a Response to Olive Oil Treatment Are Inversely Related to Lipid Oxidative Damage: The EUROLIVE Study
Objective: The aim of our study was to assess the changes in the fatty acid composition of low density lipoproteins (LDL) after sustained consumption of olive oil at real-life doses (25 mL/day) and their relationship with lipid oxidative damage. Methods: A multi-center randomized, cross-over, clinical trial with 3 similar types of olive oils, but with differences in the phenolic content, was conducted on 200 healthy European subjects. Intervention periods were of 3 weeks separated by 2-week washout periods. The LDL fatty acid content was measured in samples drawn at baseline and after the last intervention period. Results: After olive oil ingestion oleic acid concentration in LDL increased (1.9%; p Ͻ 0.001) and those of linoleic (1.1%; p Ͻ 0.002) and arachidonic acid (0.5%; p Ͻ 0.001) decreased. Monounsaturated/polyunsaturated fatty acid and oleic/linoleic acid ratios in LDL increased after olive oil consumption. An inverse relationship between the oleic/linoleic acid ratio and biomarkers of oxidative stress was observed. One unit increase in the oleic/linoleic acid ratio was associated with a decrease of 4.2 g/L in plasma isoprostanes. Conclusion: Consumption of olive oil at real-life doses improved the fatty acid profile in LDL, the changes being associated with a reduction of the oxidative damage to lipids
Rhetorical-Performative Analysis of the Urban Symbolic Landscape : Populism in Action
This chapter introduces a rhetorical-performative analysis as a tool for exploring urban symbolic landscape and populism and hence deals with relationality and materiality from the postfoundational perspective. It connects the articulation theory of cultural theorists Stuart Hall or political theorists Ernesto Laclau and Chantal Mouffe and spatial analysis of cultural geographer Doreen Massey to the study of populism. The case of Hungary shows how political frontiers have been articulated in the public space, contestable interpretations of the past are deliberately used and key symbolic urban landscapes transformed radically to articulate a political ‘us’—and ‘them.’ In the 2010s, in the Hungarian capital Budapest, the top-down process transforming urban space faced bottom-up movements which reproduce the populist logic of articulation.Peer reviewe
Prokaryotic Diversity and Distribution in Different Habitats of an Alpine Rock Glacier-Pond System
Intake of food rich in saturated fat in relation to subclinical atherosclerosis and potential modulating effects from single genetic variants
The relationship between intake of saturated fats and subclinical atherosclerosis, as well as the possible influence of genetic variants, is poorly understood and investigated. We aimed to investigate this relationship, with a hypothesis that it would be positive, and to explore whether genetics may modulate it, using data from a European cohort including 3,407 participants aged 54–79 at high risk of cardiovascular disease. Subclinical atherosclerosis was assessed by carotid intima-media thickness (C-IMT), measured at baseline and after 30 months. Logistic regression (OR; 95% CI) was employed to assess the association between high intake of food rich in saturated fat (vs. low) and: (1) the mean and the maximum values of C-IMT in the whole carotid artery (C-IMTmean, C-IMTmax), in the bifurcation (Bif-), the common (CC-) and internal (ICA-) carotid arteries at baseline (binary, cut-point ≥ 75th), and (2) C-IMT progression (binary, cut-point > zero). For the genetic-diet interaction analyses, we considered 100,350 genetic variants. We defined interaction as departure from additivity of effects. After age- and sex-adjustment, high intake of saturated fat was associated with increased C-IMTmean (OR:1.27;1.06–1.47), CC-IMTmean (OR:1.22;1.04–1.44) and ICA-IMTmean (OR:1.26;1.07–1.48). However, in multivariate analysis results were no longer significant. No clear associations were observed between high intake of saturated fat and risk of atherosclerotic progression. There was no evidence of interactions between high intake of saturated fat and any of the genetic variants considered, after multiple testing corrections. High intake of saturated fats was not independently associated with subclinical atherosclerosis. Moreover, we did not identify any significant genetic-dietary fat interactions in relation to risk of subclinical atherosclerosis
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