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Intrahepatic cholangiocarcinoma (iCCA) is the most frequent subtype of cholangiocarcinoma (CCA), and the incidence has globally increased in recent years. In contrast to surgically treated iCCA, data on the impact of fibrosis on survival in patients undergoing palliative chemotherapy are missing. We retrospectively analyzed the cases of 70 patients diagnosed with iCCA between 2007 and 2020 in our tertiary hospital. Histopathological assessment of fibrosis was performed by an expert hepatobiliary pathologist. Additionally, the fibrosis-4 score (FIB-4) was calculated as a non-invasive surrogate marker for liver fibrosis. For overall survival (OS) and progression-free survival (PFS), Kaplan–Meier curves and Cox-regression analyses were performed. Subgroup analyses revealed a median OS of 21 months (95% CI = 16.7–25.2 months) and 16 months (95% CI = 7.6–24.4 months) for low and high fibrosis, respectively (p = 0.152). In non-cirrhotic patients, the median OS was 21.8 months (95% CI = 17.1–26.4 months), compared with 9.5 months (95% CI = 4.6–14.3 months) in cirrhotic patients (p = 0.007). In conclusion, patients with iCCA and cirrhosis receiving palliative chemotherapy have decreased OS rates, while fibrosis has no significant impact on OS or PFS. These patients should not be prevented from state-of-the-art first-line chemotherapy.

The severe sliding abrasion of single-phase metallic materials is a complex issue with a gaining importance in industrial applications. Different materials with different lattice structures react distinctly to stresses, as the material reaction to wear of counter and base body is mainly determined by the deformation behavior of the base body. For this reason, fcc materials in particular are investigated in this work because, as shown in previous studies, they exhibit better hot wear behavior than bcc materials. In particular, three austenitic steels are investigated, with pure Ni as well as Ni20Cr also being studied as benchmark materials. This allows correlations to be worked out between the hot wear of the material and their microstructural parameters. For this reason, wear tests are carried out, which are analyzed on the basis of the wear characteristics and scratch marks using Electron Backscatter Diffraction. X-ray experiments at elevated temperatures were also carried out to determine the microstructural parameters. It was found that the stacking fault energy, which influences the strain hardening potential, governs the hot wear behavior at elevated temperatures. These correlations can be underlined by analysis of the wear affected cross section, where the investigated materials have shown clear differences.

Cyber-physical systems (CPS) and IoT systems are nowadays commonly designed as self-adaptive, endowing them with the ability to dynamically reconfigure to reflect their changing environment. This adaptation concerns also the security, as one of the most important properties of these systems. Though the state of the art on adaptivity in terms of security related to these systems can often deal well with fully anticipated situations in the environment, it becomes a challenge to deal with situations that are not or only partially anticipated. This uncertainty is however omnipresent in these systems due to humans in the loop, open-endedness and only partial understanding of the processes happening in the environment. In this paper, we partially address this challenge by featuring an approach for tackling access control in face of partially unanticipated situations. We base our solution on special kind of aspects that build on existing access control system and create a second level of adaptation that addresses the partially unanticipated situations by modifying access control rules. The approach is based on our previous work where we have analyzed and classified uncertainty in security and trust in such systems and have outlined the idea of access-control related situational patterns. The aspects that we present in this paper serve as means for application-specific specialization of the situational patterns. We showcase our approach on a simplified but real-life example in the domain of Industry 4.0 that comes from one of our industrial projects.

Industry 4.0 facilitates dynamic production processes for highly tailored individual products that require intense cooperation between different organisations. The enabler of such cooperation are cyber-physical systems (CPSs). A set of policies also considering dynamic changes of a request context during runtime has to protect the confidentiality of involved systems. Analysing policy effectiveness already during design time can avoid costly confidentiality flaws. However, the changes that can be evaluated during design time are not clear. Therefore, we identified typical dynamic changes from use cases we gathered with two industrial partners and categorized them accordingly.

In der vorliegenden Arbeit wird das abrasive Warmverschleißverhalten von metallischen Werkstoffen auf Fe-, Ni- und Co-Basis betrachtet. Das Ziel der Arbeit war es, die Erkenntnisse von tribologischen Betrachtungen dazu zu nutzen, um ein, an die Anforderungen des abrasiven Warmverschleißes optimal angepasstes, werkstofftechnisches Konzept zu entwickeln. Die Umsetzung dieses Vorhabens erfolgte durch eine Korrelation des Verschleißverhaltens mit den Verformungs- und Verfestigungsmechanismen sowie den zugrundeliegenden metallphysikalischen Hintergründen metallischer Legierungen. Als Ergebnis dieses Ansatzes konnten optimierte Werkstoffkonzepte auf Grundlage einer austenitischen Eisenbasis entwickelt werden, welche das Potential aufweisen im Bereich erhöhter Temperaturen mit Nickel- bzw. Kobaltbasiswerkstoffen zu konkurrieren und gleichzeitig, durch die Verwendung von kostengünstigen Eisenbasiswerkstoffen, einen ökonomischen Vorteil bieten.

Fostering efficiency of distributed supply chains in the Industry 4.0 often bases on IoT-data analysis and by means of lean- and shop oor-management. However, trust by preserving privacy is a precondition: Competing factories will not share data, if, e.g., the analysis of the data will reveal business relevant information to competitors. Our approach is enforcing privacy policies in Industry 4.0 supply chains. These are highly dynamic and therefore not manageable by 'traditional' rights-management approaches as we will stretch in a literature analysis. To enforce privacy, we analyze two industrial settings and derive general requirements: (1) Lean- and shop oor-management and (2) factory access control, both common in Industry 4.0 supply chains. We further propose a reference architecture for Industry 4.0 supply chains. We introduce the combination of Palladio Component Model (PCM) [23] and Ensembles [4] in order to analyze and enforce privacy policies in highly dynamic environments. Our novel approach paves way for data sharing and global data analyzes in highly dynamic Industry 4.0 supply chains. It is an important step for efficiency of these supply chains and therefore one important cornerstone for the success of Industry 4.0.

International Conference on Stone and Concrete Machining (ICSCM), Vol 3 (2015)