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Background: Information processing speed is commonly impaired in people with multiple sclerosis (PwMS). However, depression and fatigue can affect the cognitive profile of patients: fatigue has a negative impact from the disease's earliest stage and a reduced information processing speed is often associated with higher levels of depression. Therefore, the aim of this study was to investigate the correlations between information processing speed and physical fatigue in a cohort of Italian PwMS from a single center, considering the effect of depression. Methods: Two hundred (W = 128; mean age = 39.83 years; SD = 11.86) PwMS, from the Bari University Hospital, underwent testing for processing speed (Symbol Digit Modalities Test [SDMT]), fatigue level (Fatigue Severity Scale [FSS]), and depression (Beck's Depression Inventory [BDI]). Results: Statistically significant correlations emerged between SDMT and FSS, SDMT and BDI, FSS and BDI. Mediation analyses revealed that while physical fatigue had no significant direct negative effect on information processing speed (z=-0.891; p > 0.05), depression predicted the relationship between fatigue and information processing speed (z=-2.181; p < 0.05). Conclusion: Our findings showed that cognitive performance at SDMT was not affected by patients' perceived level of physical fatigue, but by depression. The presence of a high BDI score mediates the physical fatigue on cognitive performance impact. [ABSTRACT FROM AUTHOR]

Rotor discs for gas turbines are heavy components usually designed following a safe-life approach, where the low-cycle fatigue design is based on life curves with suitable probabilistic margins. However, in such a component, there is the possible occurrence of undetected defects that can propagate at each startup-shutdown cycle, and therefore, defect acceptance criteria have to be defined for the different rotor regions (considering stress distribution and temperature). Moreover, the failure risk should be evaluated considering static fracture at overspeed as a potential failure mode. In order to make such an assessment for a turbine rotor disc, a semi-probabilistic approach for the integrity assessment-based current standards has been developed. The approach has then been implemented into a code able to process axis-symmetric Finite Element (FE) analyses of the disc and to produce maps for the expected life (for a given defect size) and for the acceptable defect (for a target life). The probabilistic assessment of turbine rotor discs is first discussed together with a sensitivity study about the most significant calculation assumptions. Then, details of the semi-probabilistic code are shown together with application to a turbine disc. [ABSTRACT FROM AUTHOR]

In a number of previous papers, the authors have proposed a model for fracture mechanics based prediction of the S-N characteristics of metallic components with large microstructural defects. Here, an extension to materials that do not show large defects onto the fracture surfaces is provided. In such cases, an approach based on a so-called cyclic R-curve analysis is proposed for the determination of the initial flaw size, which has to be used in the calculation of fatigue crack propagation. The principle is explained and demonstrated by a first application to a welded joint. [ABSTRACT FROM AUTHOR]

This qualitative study explored the psychosocial factors that affect the implementation of an operational risk management framework in a financial institution in Tanzania. A purposive sample of 39 participants from three financial institutions was interviewed using semistructured interviews. The data were analysed by means of qualitative content analysis and the open coding procedure of grounded theory was used to identify the highlighted themes. Findings suggest that there is a movement in Tanzania towards acknowledging the value of regulatory operational risk management practices, policies and procedures. Organisations that acquire crossborder interests should take cognisance of the psychosocial factors that affect the implementation of an operational risk management framework in order to address similar challenges. [ABSTRACT FROM AUTHOR]