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An innovative net-based methodology to integrate qualitative and quantitative analysis of distributed software systems is outlined, and an on-going prototype implementation of a related graphic-oriented tool kit is sketched. The proposed method combines qualitative analysis, monitoring and testing as well as quantitative analysis on the basis of a net-based intermediate representation of the distributed software system under consideration. All transformations (from the distributed software system into a first Petri net model, and between the different kinds of net models) can be made formally, and therefore automated to a high degree. The evaluation of quantitative properties is based on so-called object nets which are obtained by a property-preserving structural compression and quantitative expansion of the qualitative model. In this way, the frequency and delay attributes necessary to generate quantitative models are provided by the monitoring and testing component.
An innovative net-based methodology to integrate qualitative and quantitative analysis of distributed software systems is outlined, and an on-going prototype implementation of a related graphic-oriented tool kit is sketched. The proposed method combines qualitative analysis, monitoring and testing as well as quantitative analysis on the basis of a net-based intermediate representation of the distributed software system under consideration. All transformations (from the distributed software system into a first Petri net model, and between the different kinds of net models) can be made formally, and therefore automated to a high degree. The evaluation of quantitative properties is based on so-called object nets which are obtained by a property-preserving structural compression and quantitative expansion of the qualitative model. In this way, the frequency and delay attributes necessary to generate quantitative models are provided by the monitoring and testing component.
Cis-diammine dichloro platinum (II) (CDDP), is a highly potent antineoplastic agent that is used in the treatment of ovarian cancer. However, the clinical use of CDDP is restricted by its severe side effects. In order to reduce these side effects and to enhance its therapeutic efficacy, we developed specific immunoconjugates consisting of the murine monoclonal antibody OC125 and CDDP, using diethylene triamine pentaacetic acid (DTPA) as a linker.
The coupling efficiencies of the different preparations synthesized, varied between 1.10±0.42 and 2.65±1.60 mol of CDDP per mol of antibody protein. Despite the chemical modification of the antibody molecule, specific binding activity of the OC125-CDDP conjugates toward the CA125 antigen was maintained as was demonstrated by means of immunohisto-/cytochemical staining of frozen sections of ovarian cancer tissue, amniotic epithelium, and the CA125 positive ovarian cancer cell line NIH:OVCAR 3.
The antiproliferative activity of the immunoconjugates was tested against the human ovarian cancer cell lines NIH:OVCAR3 and SKOV 3, applying a kinetic crystal violet microassay.
Despite the promising results obtained with the specific immuno-staining of the target cells, no significant antiproliferative activity of our immunoconjugates against the cell lines tested was observed.
One possible explanation for the lack of antitumor activity could be the fact that CA125 is released in large amounts by the NIH:OVCAR 3 cells. This may have prevented an efficient immunotargeting of the cancer cells by the formation of soluble immune complexes.
Identification of insulin and insulin-like growth factor I (IGF I) receptors in ovarian cancer
(1994)
Abstract
The objective of this study was to test if specific insulin and insulin-like growth factor I (IGF I) receptors are expressed in ovarian cancer tissue. Thirteen tissue specimens from primary ovarian cancers, 1 specimen from a primary peritoneal carcinoma, 10 specimens from metastatic lesions of ovarian carcinomas, and 4 specimens from recurrent ovarian cancers together with 13 normal ovaries were tested for their content of insulin and IGF-I receptors, by the application of specific insulin and IGF-I receptor radioimmunoassays. The insulin receptor (IR) and IGF-I receptor (IGF R) content in the primary tumors varied between 23.8-321.4 and 16.4-554.2 ng/0.1 mg DNA, respectively. Metastatic lesions contained between 12.3 and 226.7 ng IR/0.1 mg DNA and between 7.5 and 459.4 ng IGF R/0.1 mg DNA. In recurrent tumors the receptor concentrations were in the range of 41.5-79.8 and 48.9-160.9 ng/0.1 mg DNA for insulin and IGF-I receptors, respectively. Normal ovarian tissue contained between 12.2 and 150.1 ng IR and between 21.4 and 420.1 ng IGF R per 0.1 mg DNA, respectively. As both insulin and IGF-I receptors are present in ovarian cancer tissue, the effects of insulin and IGF-I as potential growth factors in ovarian cancer should be further investigated.
Copyright © 1994 Academic Press. All rights reserved.
A free boundary-value problem for a nonisothermal flow of two heavy viscous incompressible capillary liquids descibing a slot coating process is mathematically studied. The problem is stationary and two-dimensional and the Boussinesq approximation for the Navier-Stokes equations is used. The existence and uniqueness of a weak solution is proved in weighted Holder spaces for small data.
Deduktionssysteme
(1994)
Exact solutions of generalized three-particle Bargmann-Wigner equations in the strong-coupling limit
(1994)
In this paper a Petri net based methodology is outlined for an integrated qualitative and quantitative analysis of parallel software systems which is based on different (Petri) net representations of die software system under consideration. The software validation methodology starts from the source text of a set of communicating processes which specify the system under development. From this source text skeleton, a Petri net representation of the general control structure of the system is generated. On this basis a set of reduction steps is defined for transforming the net into different intermediate representations all owing the validation of both qualitative and qualitative properties. Particular attention is paid to the validation of quantitative properties which is performed using a transformation into locally Markovian Object Nets (MONs). Models of this new class of modular Petri nets are obtained by property-preserving structural compression and by enhancement with quantitative i nformation This information is obtained in the form of frequency and delay parameters by monitoring testing the software on the basis of prototypes. Compared to a previous paper on the same topic /Heiner94/ the methodology as well presentation have been improved. In particular, a new, more comprehensive running example been selected and the object net approach is explained in much more detail.
Small sodium and silver particles were generated on dielectric substrates like LiF, quartz and sapphire under ultrahigh vacuum conditions. The optical transmission spectra of the clusters were measured as a function of cluster size and shape, for low and high substrate temperatures as well as for s- and p- polarization of the incident light. Excitation of dipolar surface plasmon oscillations in the directions normal and parallel to the substrate surface could be identified. Furthermore, optical spectra for Na and Ag clusters were calculated with the classical Mie theory. The measured spectra vary strongly if the experimental conditions are changed and can be exploited, for example, to characterize the particles with regard to their size and shape. In particular, the axial ratio of the spheroidal clusters could be determined. Its value is considerably different for the two investigated metals and depends on the substrate material. Furthermore, the temperature of the substrate has a pronounced influence on the shape of the particles. At low temperature of T=100 K two-dimensional island growth is predominant. The particles extend only little in the direction perpendicular to the surface and coalesce readily at small coverage of metal atoms. In contrast, the clusters are truly three-dimensional at T=300 K. At this stage, sodium particles still exhibit a rather small axial ratio whereas silver clusters appear almost spherical. Thus, measurements of the optical spectra permit direct in situ monitoring of cluster growth during the nucleation of adsorbed atoms and of temperature induced shape variations. In addition to investigations of the shape of the particles, the quadrupolar surface plasmon mode was observed for Ag clusters.
Imaging Pattern Formation in Surface Reactions from Ultrahigh Vacuum up to Atmospheric Pressures
(1995)
Two optical methods that allow pattern formation to be investigated at an arbitrary pressure are here applied to image concentration patterns of adsorbed species associated with heterogeneous catalytic reactions. In contrast to most surface physical techniques, these methods are not restricted to high vacuum conditions and thus bridge the “pressure gap.” With carbon monoxide oxidation on a (110) surface of platinum as an example, the coupling mechanisms responsible for spatiotemporal self-organization in surface reactions were followed from reaction-diffusion control to the thermokinetic region, associated with phenomena not previously observed in pattern formation.
Two surface-sensitive optical imaging methods, Ellipso-Microscopy for surface Imaging (EMSI) and Reflection Anisotropy Microscopy (RAM) are introduced. They allow imaging of pattern formation on surfaces, e.g., due to submonolayer coverages of adsorbates, at any arbitrary pressure.
In spatio-temporal pattern formation during heterogeneously catalysed reactions this bridges the ‘pressure gap’ between well-defined UHV experiments and ‘real catalysis’. For the CO oxidation on Pt(110), the parameter space for pattern formation was extended up to 100 mbar, i.e., by 5 orders of magnitude compared to earlier investigations by Photo-Emission Electron Microscopy (PEEM) which had to be conducted below 10−3 mbar. With increasing pressure, the synchronisation mechanisms responsible for the observed pattern showed a gradual shift from reaction-diffusion to thermal-kinetic coupling unveiling previously unseen features of pattern formation in catalysis.
Analysis of a nonisothermal viscous flow problem with free boundaries and a dynamic contact line
(1995)
Effective dynamics in a subfermion shell model of leptons, quarks and electroweak gauge bosons
(1995)
Beschreibung finiter plastischer Deformationen von Einkristallen mittels materieller Isomorphismen
(1995)
Projektbericht Stadtmarketing : Ergebnisse einer Passantenbefragung in Brandenburg an der Havel
(1996)
Modular process nets are a graphical and formal notation for the representation of technical and business process models containing concurrent activities. Originally this class of Petri nets was developed for the modeling, analysis, simulation and control of workflows and computer-based process control systems, but it is also suitable for use in all other areas where a formal but comprehensible description of complex processes is needed. After a description of the basic aims and design decisions for modular process nets, the report gives a brief introduction to low-level Petri nets including different types of transition rules and aspects of the descriptive and prescriptive use of process models. The main and most innovative points which are explained in more detail are the introduction of a hierarchical module concept for nets and the definition of elementare process nets. The module concept is part of a more general ("object-based") approach to Petri nets allowing severaltypes of ab straction, whereas the main points of elementary process nets are synchronous and asynchronous communication between separately interpreted net instances via events and token passing. Modular process nets are low-level Petri nets equipped with these module and communication concepts and optionally enhanced by die use of a task concept, a method known from the areas of computer-supported cooperative work (CSCW) and work-flow management. Because the report is aimed at a systematic and easy-to-understand introduction to modular process nets, it provides a precise explanation of this net class which is kept as informal as possible and enhanced by some typical application examples
Two new optical imaging methods with submonolayer surface sensitivity are applied together to investigate pattern formation of adsorbate concentrations on surfaces during heterogeneously catalysed reactions. Ellipso-microscopy for surface imaging (EMSI) is based on an ellipsometric effect, reflection anisotropy microscopy (RAM) on the polarising properties of surface anisotropies. For the CO oxidation reaction on a Pt(110) surface features like front propagation, target patterns and spiral waves are observed, similar as in prior investigations by photoemission electron microscopy (PEEM). By applying EMSI and RAM simultaneously and imaging the same spot of the surface, supplementary information is gained on the properties of the reaction diffusion fronts. When observing a reaction front by EMSI and RAM at temperatures between 330 and 420 K the image of the front in RAM trails behind its image in EMSI. EMSI seems to display changes in the coverage of adsorbates while RAM relates to variations in surface structure.
Neutron diffraction experiments on powders are used to investigate the quantum mechanical behaviour of uniaxial rotators, i.e. NH3-molecules in Ni(NH3)6(PF6)2, Co(NH3)6(PF6)2 and Ni(NH3)6I2. A diffuse temperature dependent component of the total scattering, modulated ∼ sin QrH-H/QrH-H, is observed at a temperature of ≃ 20 K and below. This observation is due to the fact, that on cooling the sample to kT ∼ B (rotational constant) the rotational ground state is strongly populated. The ground state of a uniaxial free rotator, however, is completely polarized. As a consequence the scattering of those NH3 groups being in the ground state becomes coherent and is observable in diffraction experiments.
In dieser Arbeit wird ein Ansatz zum 'rapid prototyping' objektorientierter, heterogener, verteilter Informationssysteme auf der Basis des Tycoon-Systems entwickelt.
Dazu wird eine Methodik zur Transformation struktureller objektorientierter Informationsmodelle (exemplarisch OMT-Objektmodelle) in entsprechende Komponenten einer Software-Architektur entworfen, indem ausgehend von dem Beispiel-Szenario eines Umweltinformationssystems die typischen Elemente für heterogene, verteilte Informationssysteme in generischer Weise formuliert werden. Der Schwerpunkt liegt dabei auf dem Objektmanagement sowie der Anbindung bestehender, externer Datenbestände und deren logisch-funktionaler Integration.
Als Basis dient das Tycoon-System, das einen sprachlichen und architektonischen Rahmen für die typsichere Definition, Integration und Interoperation generischer Dienste in offenen Systemumgebungen bereitstellt und somit eine mögliche Grundlage für die Entwicklung persistenter Objektsysteme bietet. Die existierenden Tycoon-Features werden dabei für den Entwurf heterogener, verteilter Informationssysteme ausgenutzt. Die polymorphe Tycoon Language (TL) dient als Spezifikationssprache. Da objektorientierte Konzepte nicht direkt in TL integriert sind, sondern in Form generischer Bibliotheken an den Sprachkern angebunden werden müssen, wird zunächst generell untersucht, wie sich die Konzepte struktureller objektorientierter Modelle in entsprechende TL-Strukturen abbilden lassen bzw. welche objektorientierten Erweiterungen zu TL wünschenswert sind.
Reusable solid wheels manufactured of the old steel BV1 (nearly equivalent to the solid or monobloc wheel steel R1 according to the new nomenclature) show in some cases rolling defects on the surface of the wheel disc. The fatigue behaviour of such defects is analysed by means of the linear-elastic fracture mechanics and Monte Carlo simulation and assessed to be able to derive the allowable defect size for the non-destructive testing. This paper was firstly presented at the Second International Symposium on Fatigue Design FD’95, held in Helsinki (Finland) on 5 – 8 September 1995. The complete research report is published under the title „Oberflächendefekte im Scheibenbereich” (Manufacturing surface defects in the disc area of solid wheels). The research work was sponsored by the Deutsche Forschungsgemeinschaft (DFG).
The single most common cause leading to the diagnosis of endometrial cancer is postmenopausal bleeding. Although most patients with early-stage disease (FIGO stage I and II) can be cured, prognosis worsens considerably with increasing stage. While serum CA 125 levels are elevated only in a significant proportion of patients with advanced disease, recently a new serum marker (OVX1) for the detection of early-stage endometrial cancer was reported. Serum OVX1 levels were measured using an OVX1 radioimmunoassay (RIA) or enzyme immunoassay (EIA) in 192 patients with endometrial cancer. CA 125 levels were measured in 112 patients using the CIS ELSA CA 125 kit. Apparently healthy females had mean serum OVX1 levels measured with the OVX1–EIA of 1.34 ± 0.74 U/ml, while patients with endometriosis had mean OVX1 serum levels of 3.15 ± 2.45 U/ml. The mean OVX1 serum level for endometrial cancer patients was 2.00 ± 1.32 U/ml. These values were 2.76 ± 1.62, 6.10 ± 4.66, and 5.37 ± 3.49, respectively, using the OVX1–RIA assay. Applying a cutoff value of 2.8 U/ml, serum OVX1–EIA levels in endometrial cancer patients were increased in 25 of 127 patients (19.7%) with stage I disease, 5 of 17 patients with stage II (29.4%), 5 of 22 patients (22.7%) with stage III, and 4 of 11 patients (36.4%) with stage IV disease. Using the OVX1–RIA and a cutoff of 7.2 U/ml, serum levels were increased in 22 of 127 (17.3%) stage I, 6 of 17 (35.3%) stage II, 5 of 22 (22.7%) stage III, and 6 of 11 (54.5%) stage IV patients. Serum CA 125 levels, determined in a total of 112 patients, were elevated above 35 U/ml in 12 of 79 patients (15.2%) with stage I, 4 of 12 patients (33.3%) with stage II, 8 of 13 patients (61.5%) with stage III, and all of 8 patients (100%) with stage IV disease. While a good correlation between serum CA 125 levels and the clinical stage of the disease was found, no correlation could be detected for OVX1 and stage.