Towards Symbolic Model-Based Mutation Testing: Combining Reachability and Refinement Checking

Model-based mutation testing uses altered test models to derive test cases that are able to reveal whether a modelled fault has been implemented. This requires conformance checking between the original and the mutated model. This paper presents an approach for symbolic conformance checking of action systems, which are well-suited to specify reactive systems. We also consider nondeterminism in our models. Hence, we do not check for equivalence, but for refinement. We encode the transition relation as well as the conformance relation as a constraint satisfaction problem and use a constraint solver in our reachability and refinement checking algorithms. Explicit conformance checking techniques often face state space explosion. First experimental evaluations show that our approach has potential to outperform explicit conformance checkers.Comment: In Proceedings MBT 2012, arXiv:1202.582

Spielleidenschaft und Strafrecht

Spielleidenschaft und Strafrecht : eine Betrachtung zu den Glücksspieltatbeständen der §§ 284 ff. StGB. - Frankfurt am Main u.a. : Lang, 2003. - XXVI, 241, XI S. - (Europäische Hochschulschriften : Reihe 2, Rechtswissenschaft ; 3759). - Zugl.: Augsburg, Univ., Diss., 200

Release from Above- and Belowground Insect Herbivory Mediates Invasion Dynamics and Impact of an Exotic Plant

The enemy-release hypothesis is one of the most popular but also most discussed hypotheses to explain invasion success. However, there is a lack of explicit, experimental tests of predictions of the enemy-release hypothesis (ERH), particularly regarding the effects of above- and belowground herbivory. Long-term studies investigating the relative effect of herbivores on invasive vs. native plant species within a community are still lacking. Here, we report on a long-term field experiment in an old-field community, invaded by Solidago canadensis s. l., with exclusion of above- and belowground insect herbivores. We monitored population dynamics of the invader and changes in the diversity and functioning of the plant community across eight years. Above- and belowground insects favoured the establishment of the invasive plant species and thereby increased biomass and decreased diversity of the plant community. Effects of invertebrate herbivores on population dynamics of S. canadensis appeared after six years and increased over time, suggesting that long-term studies are needed to understand invasion dynamics and consequences for plant community structure. We suggest that the release from co-evolved trophic linkages is of importance not only for the effect of invasive species on ecosystems, but also for the functioning of novel species assemblages arising from climate change

Interdisciplinary engineering of cyber-physical production systems

In the context of cross-disciplinary and cross-company cooperation, several challenges in developing manufacturing systems are revealed through industrial use cases. To tackle these challenges, two propositions are used in parallel. First, coupling technical models representing different content areas facilitates the detection of boundary crossing consequences, either by using a posteriori or a priori connection. Second, it is necessary to enrich these coupled technical models with team and organizational models as interventions focusing on the collaboration between individuals and teams within broader organizational conditions. Accordingly, a combined interdisciplinary approach is proposed. The feasibility and benefits of the approach is proven with an industrial use case. The use case shows that inconsistencies among teams can be identified by coupling engineering models and that an integrated organizational model can release the modelling process from communication barriers

Evidence of Human Milk Oligosaccharides in Cord Blood and Maternal-to-Fetal Transport across the Placenta

Human milk oligosaccharides (HMOs) are present in maternal serum in early gestation, raising the question of whether HMOs can cross the placental barrier and reach fetal circulation. Here, we aimed to detect HMOs in cord blood, and assess HMO composition and concentration in relation to maternal HMOs. In an ex-vivo placental perfusion model, we asked whether HMOs can pass over the placenta. Using HPLC, we measured HMOs in maternal serum and matching venous cord blood samples collected at delivery from normal pregnancies (n = 22). To investigate maternal-to-fetal transport, we perfused isolated placental cotyledons from term pregnancies (n = 3) with 2’-fucosyllactose (2′FL) in a double closed setting. We found up to 18 oligosaccharides typically present in maternal serum in all cord serum samples investigated. Median total cord blood HMO concentration did not differ from the concentration in maternal serum. HMO composition resembled the composition in maternal serum, with the strongest correlations for 2′FL and LDFT. After 180 min perfusion, we found 22% of maternally offered 2′FL in the fetal circuit without reaching equilibrium. Our results provide direct evidence of HMOs in cord blood, and suggest that the placenta transfers HMOs from the maternal to fetal circuit. Future studies will investigate potential differences in the transfer of specific HMOs, or in pregnancy disorders

Human Milk Oligosaccharides in Cord Blood Are Altered in Gestational Diabetes and Stimulate Feto-Placental Angiogenesis In Vitro

(1) Background: Human milk oligosaccharides (HMOs) are present in maternal serum during pregnancy and their composition is altered in gestational diabetes (GDM). HMOs are also in fetal cord blood and in contact with the feto-placental endothelium, potentially affecting its functions, such as angiogenesis. We hypothesized that cord blood HMOs are changed in GDM and contribute to increased feto-placental angiogenesis, hallmark of GDM. (2) Methods: Using HPLC, we quantified HMOs in cord blood of women with normal glucose tolerance (NGT, n = 25) or GDM (n = 26). We investigated in vitro angiogenesis using primary feto-placental endothelial cells (fpECs) from term placentas after healthy pregnancy (n = 10), in presence or absence of HMOs (100 µg/mL) isolated from human milk, 3′-sialyllactose (3′SL, 30 µg/mL) and lactose (glycan control) and determined network formation (Matrigel assay), proliferation (MTT assays), actin organization (F-actin staining), tube formation (fibrin tube formation assay) and sprouting (spheroid sprouting assay). (3) Results: 3′SL was higher in GDM cord blood. HMOs increased network formation, HMOs and 3’SL increased proliferation and F-actin staining. In fibrin assays, HMOs and 3’SL increased total tube length by 24% and 25% (p p p = 0.056), respectively. Lactose had no effect. (4) Conclusions: Our study suggests a novel role of HMOs in feto-placental angiogenesis and indicates a contribution of HMO composition to altered feto-placental vascularization in GDM