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Ohne Zusammenfassung     

Patent information in a large electrical company, exemplified by the situation at Siemens

The special situation of patent information is dealt with against the background of the general problems of information provision. The role of the Patent Department of Siemens as a user of patent information and in the distribution of patent information within the company is discussed. Finally, the present system of current patent information on granted patents and first publications is outlined and an outlook on future developments given.     

Uniaxial compression of Swiss-type cheese at different strain rates

Rheological behaviour of 48 Swiss-type cheese samples in lubricated uniaxial compression was evaluated at three initial strain rates ranging from 4·76 × 10⁻³ to 7·62 × 10⁻² s⁻¹. Modulus, apparent fracture stress and apparent fracture strain increased significantly with increasing strain rate, which is attributed to the viscoelastic nature of cheese. The influence of strain rate on apparent fracture strain strongly depended on the shape of the stress-strain curves. The relationship between the rheological parameters evaluated at different strain rates proved to be significant. The strain rate dependency of the apparent fracture strain is further explained by the contribution of elastic and viscous components, which was evaluated in relaxation experiments in the linear viscoelastic region.     

Microcalorimetry for characterization of film formation and cure of coatings and adhesives

A new microcalorimeter with eight parallel channels using robust, low cost sensors for characterization of coatings and adhesives is described and first experiments on coatings and adhesives are presented. The calorimetric sensors are based on thin glass plates (20 mm × 20 mm, thickness 150 μm) with heater and thermocouple sputtered on the surfaces (calorimetric active area of about 9 mm²). The setup allows heating and cooling experiments as well as isothermal measurements in the temperature-modulated mode with up to eight sensors in parallel. The measured quantities are the real (C^′_p) and imaginary part (C^″_p) of the complex heat capacity (), the related absolute value of the heat capacity () and the heat flow . An industrial computer (NI PXI system) with specific software for calibration and data recording controls the electronic components. Sensors can be embedded in a temperature controlled oven (heating and cooling by Peltier elements) or alternatively in a climatic cabinet with controlled temperature and humidity.

The method has been applied successfully to monitoring of film formation of aqueous polymer dispersions (styrene-acrylate copolymer) and curing of coatings.     

Prognosis of hematological patients with relapse following high-dose chemotherapy and autologous stem cell transplantation

A retrospective analysis of the outcome for 283 haematological patients who relapsed after high dose chemotherapy and autologous stem cell transplantation during a five year period from 1989 to 1994 is presented. The patients were treated in accordance with local regimes at 20 Nordic transplantation centers and included patients with acute leukemia (157 patients), multiple myeloma (16 patients) and lymphoma (110 patients). Two hundred and twenty-nine patients with relapse or progressive disease were given chemo- and/or radiotherapy and the response was evaluated after 90 days. Fifty-four patients (24%) obtained a complete remission and 44 patients (19%) partial remission. The overall median survival after relapse was five months. In the group who received salvage treatment the median survival was seven months, and for the 54 patients in complete remission the median survival was 15 months. We found that survival after relapse depends upon primary disease, the time from transplantation to relapse and whether salvage therapy was initiated.     

On mesh-free valley surface extraction with application to low frequency sound simulation

Crease surfaces describe extremal structures of 3D scalar fields. We present a new region-growing-based approach to the meshless extraction of adaptive nonmanifold valley and ridge surfaces that overcomes limitations of previous approaches by decoupling point seeding and triangulation of the surface. Our method is capable of extracting valley surface skeletons as connected minimum structures. As our algorithm is inherently mesh-free and curvature adaptive, it is suitable for surface construction in fields with an arbitrary neighborhood structure. As an application for insightful visualization with valley surfaces, we choose a low frequency acoustics simulation. We use our valley surface construction approach to visualize the resulting complex-valued scalar pressure field for arbitrary frequencies to identify regions of sound cancellation. This provides an expressive visualization of the topology of wave node and antinode structures in simulated acoustics.     

Control of yeast neutral trehalase by distinct polyphosphates and ribonucleic acid

Summary The activity of yeast trehalase when assayed at pH 7 in a crude extract was found to increase 2- to 3-fold upon incubation with 0.1 % (v/v) polyethyleneimine or other polycations such as polylysine (0.075-mMol) and calf thymus histories (0.08 mMol). Incubation with 3 mM-Mn²⁺ and 5 mM-Ca²⁺ also led to 3- and 1.6-fold increases in trehalase activity, respectively. The activities of 11 other enzymes assayed in the crude yeast extract did not increase after addition of polyethylene imine. At concentrations of polyethylenemine that maximally stimulated trehalase activity, 97% of the total RNA present in the crude extract, 40% of total protein, and 60% of the polyphosphate (assayed as inorganic phosphate liberated during 7 min incubation at 95 °C and pH O) were found to be precipitated. A similar finding was made with trehalase-stimulating concentrations of Mn²⁺. Activation of trehalase by polyethylene imine rendered this enzyme susceptible to inhibition by a preparation of total yeast RNA, inorganic polyphosphates, and related polyanions. We present further evidence that the removal of a distinct RNA and/or polyphosphate is the basic principle of polyetyleneimine-induced activation of trehalase.A more pronounced stimulation of trehalase activity (4-fold) could be obtained by enzymatic phosphorylation with ATP in the presence of cyclic AMP and Mg²⁺ as described by van Solingen and van der Plaat (1975) [9]. Thus, trehalase 2-fold activated by polyethylene imine was further activated by another 2-fold increase by enzymatic phosphorylation. Conversely, no additional stimulation by polyethylene imine was obtained for the maximally active, phosphorylated enzyme. We conclude that phosphorylation-mediated activation of trehalase is a two-step event, one being the removal of an inhibitor, which can be achieved by polyethylene imine or related cations independent on phosphorylation. The most likely candidate for the inhibitor appears to be a distinct RNA.

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Kontrolle der neutralen Hefen-Trehalase durch bestimmte Polyphosphate und RNA

Zusammenfassung Die in einem rohen Extrakt aus Hefe bei pH 7 gemessene Aktivität von Trehalase nimmt bei der Inkubation mit 0,1% Polyethylenimin oder mit anderen Polykationen, wie Polylysin (0,075 mmol) oder Histon aus Kalbsthymus (0,08 mmol) auf das zwei- bis dreifache zu. Auch die Inkubation mit 3 mmol Mn²⁺ oder 5 mmol Ca²⁺ führt zu einer 3-, bzw. 1,6fachen Zunahme der Trehalase-Aktivität. Die Aktivität von 11 anderen Enzymen, die im rohen Extrakt aus Hefe bestimmt wurden, nimmt nach Zusatz von Polyethylenimin nicht zu. Bei der Inkubation mit Polyethylenimin, das eine maximale Stimulierung der Trehalase-Aktivität bewirkt, werden 97% der gesamten Ribonucleinsäure, 40% des gesamten Proteins und 60% des Polyphosphats (bestimmt als anorganisches Phosphat, das in 7 min bei 95 °C und pH O freigesetzt wird) präcipitiert. Eine gleichartige Präcipitation wurde bei der Inkubation mit Trehalase-stimulierenden Konzentrationen von Mn²⁺ beobachtet. Mit Polyethylenimin aktivierte Trehalase wird durch Ribonucleinsäure aus Hefe, anorganisches Polyphosphat und verwandte Polyanionen gehemmt. Vermutlich führt die Entfernung einer bestimmten Ribonucleinsäure-Fraktion und/oder von Polyphosphat zu der Polyethylenimin-induzierten Aktivierung der Trehalase.Wie von van Solingen und van der Plaat 1975 beschrieben [9], wird eine 4fache Stimulierung von Trehalase durch enzymatische Phosphorylierung mit ATP in der Gegenwart von cyclischem AMP und Mg²⁺ erreicht. Das so durch Phosphorylierung maximal aktivierte Enzym kann durch Zusatz von Polyethylenimin nicht weiter aktiviert werden. Das mit Polyethylenimin 2fach aktivierte Enzym kann jedoch noch einmal 2fach weiter aktiviert werden durch enzymatische Phosphorylierung. Aus diesen Beobachtungen wird geschlossen, daß die durch enzymatische Phosphorylierung bewirkte Aktivierung der Trehalase ein zweistufiger Vorgang ist: Zuerst findet die Entfernung eines Inhibitors statt (dies kann auch mit Polyethylenimin oder mit verwandten Kationen unabhängig von der enzymatischen Phosphorylierung erreicht werden), hierauf folgt weitere Aktivierung durch Konformationsänderung des Enzyms. Wahrscheinlich handelt es sich bei dem durch Phosphorylierung bzw. Behandlung mit Polyethylenimin abgetrennten Inhibitor um eine gewisse Ribonucleinsäure-Fraktion.

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Abbreviation PEI polyethylene imine The followingenzymes are mentioned in the text: Alcohol dehydrogenase Glyceraldehyde-3-phosphate dehydrogenase (1.1.1.12), Malate dehydrogenase (1.1.1.37), Glucose-6-phosphate dehydrogenase (1.1.1.49), Glutamate dehydrogenase (NAD) (1.4.1.2), Glutamate dehydrogenase (NADP) (1.4.1.4), Aspartate -ketoglutarate aminotransferase (2.6.1.1), 6-Phosphofructokinase (2.7.1.11), Neutral trehalase (3.2.1.28), Pyruvate decarboxylase (4.1.1.1), Phosphoenolpyruvate carboxykinase (4.1.1.49).This paper is dedicated to Prof. Dr. Karl Decker on the occasion of his 60th birthday