Zur konvektiven Wärmeübertragung an Außenflächen von Industrieöfen

Untersuchung der konvektiven Wärmeübertragung an waagerechten und senkrechten Flächen. Vergleich der Ergebnisse mit Schrifttumsangaben. Versuche über den gegenseitigen Einfluβ waagerechter und senkrechter Flächen aufeinander bei konvektiver Wärmeübertragung an einem idealisierten Ofen (oberflächenbeheizter Würfel). Entwicklung einer Gebrauchsformel für die konvektive Wärmeübertragung an Auβenflächen von Industrieöfen.     

Pedestrian Travel Behavior Modeling

This paper presents a dynamic mixed discrete-continuous choice approach to modeling pedestrian travel and activity choice behavior in public facilities. The approach views revealed behavior as a manifestation of pedestrians’ preferences by assuming that pedestrians choose the alternative that maximizes expected (subjective) utility, while taking into account the uncertainty in expected traffic conditions. The choice dimensions are trajectories between origin and subsequent destinations, areas where activities are performed (multiple vs. fixed destination), execution of discretionary activities, and finally activities completion times and order.The disutility of a trajectory determines the trajectory choice of the traveler. Destination area choice is included in the modeling by determining time-dependent and destination-specific arrival costs. Furthermore, penalties for not executing a planned activity are introduced into the modeling framework. The resulting modeling approach has a clear analogy with stochastic control theory and dynamic programming in continuous time and space.The main innovations presented here is the relaxation of the assumption that routes are discrete sets of travel links. The approach relaxes the need to build a discrete network, while routes (trajectories) are continuous functions in time and space. At the same time, destination choice is included in the modeling framework.     

Induction of electrophile-responsive element (EpRE)-mediated gene expression by tomato extracts in vitro

The market for food products with additional health benefits is increasing rapidly and tools for identification of bio-functional characteristics of food items are essential. To facilitate the detection of beneficial effects of tomato on gene expression, methods to prepare tomato extracts suitable to test in the EpRE LUX assay and other cell-based reporter gene assays for health-related bioactivity mechanisms, were developed. An isoprenoid-containing chloroform extract of tomato fruit and most individual isoprenoids did not induce electrophile-responsive element (EpRE)-mediated gene expression. A semi-polar extract of tomato fruits, enzymatically hydrolysed to remove the glycosyl residues from the phenolic ingredients was able to induce EpRE-mediated luciferase expression at both mRNA and protein level, which might be partly due to the presence of quercetin, kaempferol, naringenin and naringenin chalcone. It was concluded that induction of EpRE-regulated genes, such as detoxifying phase II and antioxidant enzymes, may contribute to the beneficial health effects of tomato.     

Extended time-to-collision measures for road traffic safety assessment

This article describes two new safety indicators based on the time-to-collision notion suitable for comparative road traffic safety analyses. Such safety indicators can be applied in the comparison of a do-nothing case with an adapted situation, e.g. the introduction of intelligent driver support systems. In contrast to the classical time-to-collision value, measured at a cross section, the improved safety indicators use vehicle trajectories collected over a specific time horizon for a certain roadway segment to calculate the overall safety indicator value. Vehicle-specific indicator values as well as safety-critical probabilities can easily be determined from the developed safety measures. Application of the derived safety indicators is demonstrated for the assessment of the potential safety impacts of driver support systems from which it appears that some Autonomous Intelligent Cruise Control (AICC) designs are more safety-critical than the reference case without these systems. It is suggested that the indicator threshold value to be applied in the safety assessment has to be adapted when advanced AICC-systems with safe characteristics are introduced.     

Citrus phenylpropanoids and defence against pathogens. Part I: Metabolic profiling in elicited fruits

Penicillium spp. are among the major postharvest pathogens of citrus fruit. Induction of natural resistance in fruits constitutes one of the alternatives to chemical fungicides. Here, we investigated the involvement of the phenylpropanoid pathway in the induction of resistance in Navelate oranges by examining changes in the metabolic profile of upon eliciting citrus fruits. By using both HPLC-PDA-FD and HPLC-PDA-QTOF–MS allowed the identification of several compounds that seem to be relevant for induced resistance. In elicited fruits, a greater diversity of phenolic compounds was observed in the flavedo (outer coloured part of the peel) when compared to the albedo (inner white part). Moreover, only small changes were detected in the most abundant citrus flavonoids. The coumarin scoparone was among the compounds with the highest induction upon elicitation. Two other highly induced compounds were identified as citrusnin A and drupanin aldehyde. All three compounds are known to exert antimicrobial activity. Our results suggest that phenylpropanoids and their derivatives play an important role in the induction of resistance in citrus fruit.