Vaccination with tumor cells engineered to secrete interleukin 2-immunoglobulin G fusion protein induces tumor rejection

Here we provide proof that the injection of tumor cells engineered to secrete interleukin 2 (IL-2)-IgG chimeric proteins locally induces potent antitumor responses, which are more effective than tumor transfection with IL-2 alone. Murine plasmacytoma cells (J558L) were stably transfected with DNA coding for a human IL-2-IgG1 or a murine IL-2-IgG2b fusion protein and were injected s.c. into syngeneic BALB/c mice. Evaluation of tumor growth and rejection patterns showed that IL-2-IgG secretion by transfected J558L tumor cells induced their rejection in all animals tested, similar to the rejection of J558L cells engineered to secrete IL-2 alone, whereas treatment with parental cells was lethal. However, mice treated with IL-2-IgG-secreting J558L cells (human IL-2-IgG1 and murine IL-2-IgG2b) exhibited a significantly stronger tumor immunity against a later challenge with parental J558L cells than mice treated with IL-2-secreting tumor cells.     

Characterisation of structured hydrolysis catalysts for urea-SCR

In the current study the performance of different substrates with respect to pressure drop, mixing between catalyst channels and urea conversion efficiency were measured. An increase of the volumetric conversion efficiency was found when structured substrates were applied. Also the use of solid-urea aerosol was compared to the AdBlue technology and found to be a promising alternative.     

Temporärer Korrosionsschutz von Spannstählen mit filmbildenden Mitteln

Temporary corrosion protection of prestressing steels with film forming coatings Prestressing steels may be subjected to corrosive conditions during the manufacturing process at building sites. Due to this a risk of hydrogen induced stress corrosion cracking of the steels may arise. Electrochemical investigations and constant load tests have been carried out to show the suitability of different film forming coatings to be applied as temporary corrosion protection measures. The results indicated the applicability of two agents involved in the investigations without any risk for post tensioning purposes.     

The determination of maintenance strategies for plants subject to breakdown

When plant components fail the opportunity may be taken during the ensuing shut down to carry out maintenance on other components which have not yet failed. The choice of components for this opportunity maintenance depends on the probability distributions of their residual operating lives which may, in turn, be influenced by the process operating conditions. Three methods are described for determining the strategy of opportunity maintenance which will maximize the overall performance of the plant. The problem posed in the form of a stochastic decision tree is treated by a branch and bound procedure using first a Monte Carlo simulation and secondly multidimensional numerical integration formulae to account for the stochastic variables. The third method treats the problem as a Markov decision process. This proves to have computational advantages particularly when treating broad component life time distributions and long planning periods. Furthermore, the dynamic programming nature of the Markov procedure yields maintenance strategies for all defined states of the system from a single computational run.     

Langzeitverhalten feuerverzinkter Stahlrohre in Trinkwasser unterschiedlichen pH-Wertes und unterschiedlicher Strömungsgeschwindigkeit

Long term performance of galvanized steel tubes in drinking water with different pH-value and flow velocity A 10 years' test program on galvanized steel tubes exposed to Berlin drinking water produced evidence that an undisturbed operation can only be guaranteed as long as the inner surface of the tubes is coated by metallic zinc. The zinc loss with time strongly depends on the pH-value and can be expressed by the mathematical equation . Due to the typical shape of the logarithmical function and its dependence on the pH-value a small increase of pH-value leads to an over-proportional increase in life-time of the zinc coating. pH = 7 leads to a total zinc loss within two years, whereas in the case of pH = 8 a zinc coating of 25–40 μm is still present after 10 year's time.     

Margin-based first-order rule learning

We present a new margin-based approach to first-order rule learning. The approach addresses many of the prominent challenges in first-order rule learning, such as the computational complexity of optimization and capacity control. Optimizing the mean of the margin minus its variance, we obtain an algorithm linear in the number of examples and a handle for capacity control based on error bounds. A useful parameter in the optimization problem tunes how evenly the weights are spread among the rules. Moreover, the search strategy for including new rules can be adjusted flexibly, to perform variants of propositionalization or relational learning. The implementation of the system includes plugins for logical queries, graphs and mathematical terms. In extensive experiments, we found that, at least on the most commonly used toxicological datasets, overfitting is hardly an issue. In another batch of experiments, a comparison with margin-based ILP approaches using kernels turns out to be favorable. Finally, an experiment shows how many features are needed by propositionalization and relational learning approaches to reach a certain predictive performance. Editors: Stephen Muggleton, Ramon Otero, Simon Colton.     

Radioaktivit?tsgehalte von 1987 und 1988 im Raum Karlsruhe gesammelten Pilzen

Zusammenfassung In den Jahren 1987 und 1988 wurde die 1986 nach dem Reaktorunfall von Tschernobyl begonnene Beobachtung der radioaktiven Kontamination von Wildpilzen im Raum Karlsruhe, Südpfalz, Nordschwarzwald und südlicher Kraichgau fortgesetzt. Gammaspektrometrisch wurden Cs-134, Cs-137, Ag-110m und das natürliche Nuklid K-40 bestimmt. Bei der Zusammenfassung der Daten aller Pilzarten und Wuchsorte zeigten sowohl Mittelals auch Höchstwerte der Radio-cäsiumgehalte von 1986 bis 1988 eine abnehmende Tendenz. Proben der gleichen Arten und vom gleichen Wuchsort zeigten jedoch im Verlauf dieser Jahre sehr unterschiedliche Radiocäsiumgehalte, obwohl nicht einzelne Pilze, sondern Mischproben gemessen wurden. Als Cäsium-Sammler erwiesen sich vor allem Lackbläuling, Maronenröhrling, Rotfußröhrling, Trompetenpfifferling, Roter Lacktrichterling und Zitronentäubling mit Höchstwerten von 3600 (1986), 2000 (1987) und 1200 (1988) Bq/kg Radiocäsium. Daneben gibt es eine größere Zahl von Pilzarten, die Cäsium nur wenig oder überhaupt nicht aufnehmen, wie Maipilz oder Schopftintling. Eine Anreicherung von Silber fand sich beim Safranschirmling und Schafegerling, in denen Ag-110m (max. 11 Bq/kg) nachgewiesen wurde.

---

Radioactivity levels in mushrooms collected in the area of Karlsruhe during 1987 and 1988

Summary Radioactive contamination of wild-growing mushrooms collected in the Northern Black Forest and neighbouring Rhine Valley area has been monitored since the Chernobyl reactor accident. Cs-134, Cs-137, Ag-100m and the natural nuclide K-40 were determined by gamma-spectrometry. Pooled data from all species and all locations showed a decrease in the radio-caesium levels from 1986 to 1988, both in mean values and maximum values. Samples of the same species collected at the same location exhibited large differences, although mixed samples rather than individual mushrooms were measured. Accumulation of caesium was observed particularly inLaccaria amethystina, Xerocomus badius, Xerocomus chrysenteron, Cantharellus tubaeformis, Laccaria laccata, andRussula ochroleuca with maximum values of 3600 (1986), 2000 (1987), and 1200 (1988) Bq/kg of radiocaesium. A large number of species, among themCalocybe gambosa andCoprinus comatus, showed very small accumulations or no caesium. An accumulation of silver was found inMacrolepiota rhacodes andAgaricus arvensis, which contained a maximum of 11 Bq/kg Ag-110m.

     

Effect of friction stir welding process on microstructural characteristics and corrosion properties of steels for naval applications

ABSTRACT

Electrochemical properties and microstructure examinations have been performed on three Friction Stir Welded (FSW) shipbuilding steels (DH36, S690QL, 80HLES). Galvanic coupling has been assessed using Scanning ElectroChemical Microscopy (SECM) and an electrochemical mini-cell in order to subsequently identify possible FSW-related damages of these steels. The galvanic macro-coupling between the base material and the welded zone is measured by the SECM tip. The 80HLES steel has greater differences in surface hardness and electrochemical reactivity which lead to a galvanic coupling inducing an initiation to corrosion.     

Ergonomic research study on aircraft luggage handling.

In this study, the lifting and carrying of freight and luggage at a large German airport is classified by typical conditions of performance. These manual load handling tasks take place in height-restricted workplaces. Different methods for an ergonomic evaluation of these tasks are used. The results of the epidemiological, physiological, and biomechanical studies indicated a strain bottleneck during loading tasks in aircraft holds. Therefore, an additional laboratory study was done, in order to analyse the influence of work weight and weight of work object on heart rate, subjective RPE, and number of work objects handled. As a result of the study, the airport has developed a special lifting and carrying training for the aircraft handlers which aims to reduce strain on the postural and locomotor apparatus by an appropriate technique of work. The training programme consists of theoretical instruction by a company doctor and practical exercises under the supervision of a specially-trained sports teacher.