| 1. |
- de Giuseppe, Nicola, et al.
(författare)
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A grey-box approach to the functional testing of complex automatic train protection systems
- 2005
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Ingår i: Dependable Computing - EDCC 5. - Berlin, Heidelberg : Springer. - 9783540257233 - 9783540320197 ; , s. 305-317
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Konferensbidrag (refereegranskat)abstract
- Systematic functional testing is a fundamental step of embedded control systems development cycle, as it allows to verify and validate their final implementation. Various approaches to black-box testing have been proposed, however they either involve test-case explosion or do not ensure the correctness of system behaviour in scenarios not covered by system specifications. To cope with such issues, a methodology which better suits both complexity and safety-criticality of the target system is needed. This paper describes the ASF functional testing methodology, based on a grey-box approach aimed at generating and reducing an extensive set of influence variables and test-cases. The methodology, embracing different aspects of system test process (code coverage verification, regression testing, etc.), was successfully applied to validate ASF implementation of SCMT (an Italian project for an Automatic Train Protection System). The results obtained in our testing experience proved the time effectiveness and extensive coverage of the proposed approach.
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| 2. |
- De Nicola, Giuseppe, et al.
(författare)
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A hybrid testing methodology for railway control systems
- 2004
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Ingår i: Computer Safety, Reliability, and Security. SAFECOMP 2004. - Berlin, Heidelberg : Springer. - 9783540231769 - 9783540301387 ; , s. 116-129
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Konferensbidrag (refereegranskat)abstract
- International standards for V&V processes prescribe systematic testing as a fundamental step of safety-critical systems life-cycle, in order to prove the fulfilment of their requirements. However, proposed approaches are quite general and, for complex systems, imply an excessive number of test-cases to ensure the correctness of system behaviour in any operating scenarios, including unexpected ones. A more detailed methodology is needed to extensively test all the aspects of a complex system, while keeping the number of test-cases below a reasonable threshold. This paper describes the ASF hybrid testing methodology, combining black-box and white-box techniques, based on the identification and reduction of influence variables. Such an approach was successfully applied to validate ASF implementation of the SCMT system (an Italian Automatic Train Control specification), showing its time effectiveness and full achieved coverage. The same methodology, with the related customization, is now being improved in order to test the new ERTMS/ETCS systems. © Springer-Verlag 2004.
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| 3. |
- Del Piano, Filomena, et al.
(författare)
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Subchronic oral exposure to polystyrene microplastics affects hepatic lipid metabolism, inflammation, and oxidative balance in gilthead seabream (Sparus aurata )
- 2024
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Ingår i: ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY. - 0147-6513 .- 1090-2414. ; 279
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Tidskriftsartikel (refereegranskat)abstract
- Microplastics (MPs) pose a clear threat to aquatic organisms affecting their health. Their impact on liver homeostasis, as well as on the potential onset of nonalcoholic fatty liver disease (NAFLD), is still poorly investigated and remains almost unknown. The aim of this study was to evaluate the outcomes of subchronic exposure to polystyrene MPs (PS-MPs; 1-20 mu m; 0, 25, or 250 mg/kg b.w./day) on lipid metabolism, inflammation, and oxidative balance in the liver of gilthead seabreams (Sparus aurata Linnaeus, 1758) exposed for 21 days via contaminated food. PS-MPs induced an up-regulation of mRNA levels of crucial genes associated with lipid synthesis and storage (i.e., PPARy, Srebp1, Fasn) without modifications of genes involved in lipid catabolism (i.e., PPAR alpha, HL, Pla2) or transport and metabolism (Fabp1) in the liver. The increase of CSF1R and pro-inflammatory cytokines gene expression (i.e., TNF-alpha and IL-1 beta) was also observed in exposed fish in a dose-dependent manner. These findings were confirmed by hepatic histological evaluations reporting evidence of lipid accumulation, inflammation, and necrosis. Moreover, PS-MPs caused the impairment of the hepatic antioxidant defense system through the alteration of its enzymatic (catalase, superoxide dismutase, and glutathione reductase) and nonenzymatic (glutathione) components, resulting in the increased production of reactive oxygen species (ROS) and malondialdehyde (MDA), as biomarkers of oxidative damage. The alteration of detoxifying enzymes was inferred by the decreased Ethoxyresorufin-O-deethylase (EROD) activity and the increased activity of glutathione-S-transferase (GST) at the highest PS-MP dose. The study suggests that PS-MPs affect the liver health of gilthead seabream. The liver dysfunction and damage caused by exposure to PS-MPs result from a detrimental interplay of inflammation, oxidative damage, and antioxidant and detoxifying enzymatic systems modifications, altering the gut-liver axis homeostasis. This scenario is suggestive of the involvement of MP-induced effects in the onset and progression of hepatic lipid dysfunction in gilthead seabream.
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| 4. |
- Esposito, Marco, 1965, et al.
(författare)
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Posterior jaws rehabilitated with partial prostheses supported by 4.0 x 4.0 mm or by longer implants: Four-month post-loading data from a randomised controlled trial.
- 2015
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Ingår i: European journal of oral implantology. - 1756-2406. ; 8:3, s. 221-30
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Tidskriftsartikel (refereegranskat)abstract
- To evaluate whether 4.0 x 4.0 mm dental implants could be an alternative to implants at least 8.5 mm long, which were placed in posterior jaws in the presence of adequate bone volumes.One hundred and fifty patients with posterior (premolar and molar areas) mandibles having at least 12.5 mm bone height above the mandibular canal or 11.5 mm bone height below the maxillary sinus, were randomised according to a parallel group design, in order to receive one to three 4.0 mm-long implants or one to three implants which were at least 8.5 mm long, at three centres. All implants had a diameter of 4.0 mm. Implants were loaded after 4 months with definitive screw-retained prostheses. Patients were followed up to 4-month post-loading and outcome measures were prosthesis and implant failures, any complications and peri-implant marginal bone level changes.No patients dropped-out before the 4-month evaluation. Three patients experienced the early failures of one 4.0 mm-long implant each, in comparison to two patients who lost one long implant each (difference in proportion = 0.01; 95% CI -0.06 to 0.09; P = 0.50). Consequently, two prostheses in each group could not be delivered as planned (difference in proportion = 0; 95% CI -0.07 to 0.07; P = 0.69), and one patient from each group is still waiting to have their prostheses delivered. Three short implant patients experienced three complications versus two long implant patients (difference in proportion = 0.01; 95% CI -0.06 to 0.09; P = 0.50). There were no statistically significant differences in prosthesis failures, implant failures and complications. Patients with short implants lost on average 0.38 mm of peri-implant bone at 4 months and patients with long mandibular implants lost 0.42 mm. There were no statistically significant differences in bone level changes up to 4 months between short and long implants (mean difference = 0.04 mm; 95% CI: -0.041 to 0.117; P = 0.274).Four months after loading, 4.0 x 4.0 mm implants achieved similar results as 8.5 x 4.0 mm-long or longer implants in posterior jaws, however 5 to 10 years post-loading data are necessary before reliable recommendations can be made.
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