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161.
Zusammenfassung Personenbezogene Daten müssen gel?scht werden, wenn sie für die weiteren Gesch?ftprozesse der Unternehmen nicht mehr erforderlich
sind und auch gesetzliche Aufbewahrungsfristen der L?schung nicht im Wege stehen. In der Praxis wird dieser L?schpflicht allerdings
nur zurückhaltend Rechnung getragen. Der Beitrag begründet das Erfordernis konsequenten L?schens und will dazu motivieren,
den gesetzlich vorgegebenen L?schpflichten durch ein L?schkonzept Rechnung zu tragen.
Reinhard Fraenkel ist nach verschiedenen T?tigkeiten in der Industrie seit 1994 als Rechtsanwalt in Gütersloh t?tig. Zu seinen
Arbeitsschwerpunkten z?hlt das Datenschutzrecht. Seit August 2004 ist er externer Datenschutzbeauftragter der Toll Collect
GmbH.
Dr. Volker Hammer ist Consultant der Secorvo GmbH. Seit Mitte 2003 unterstützt er die Toll Collect GmbH in verschiedenen Datenschutz-Projekten.
Weitere Arbeitsschwerpunkte sind Public Key Infrastrukturen und kritische IT-Infrastrukturen 相似文献
162.
David Rafaja Milan Dopita Magsud Masimov Volker Klemm Nina Wendt Walter Lengauer 《International Journal of Refractory Metals and Hard Materials》2008,26(3):263-275
Combination of X-ray diffraction (XRD) and scanning electron microscopy (SEM) was used for investigation of local composition gradients in the hard-phases of cermets. XRD revealed distribution of lattice parameters in hard-phase grains, from which the composition gradients in the hard-phases were estimated using an appropriate microstructure model. This microstructure model was build with the aid of SEM micrographs, which were taken with back-scattered electrons (BSE) and completed by the registration of the electron back-scatter diffraction (EBSD) patterns and characteristic X-ray spectra. SEM/BSE yielded the first information about the spatial distribution of elements in individual hard-phase grains, SEM/EBSD about the morphology, the size and the size distribution of these grains. The final interpretation of the distribution of lattice parameters, which was obtained from the X-ray line profile analysis, was done with the aid of the local elemental analysis that was performed using SEM with the energy dispersive analysis of the characteristic X-ray spectra (EDX) and the known dependence of the lattice parameters on concentration. 相似文献
163.
164.
Volker Siegel 《Informatik-Spektrum》2005,28(5):403-406
Zusammenfassung Quellcodehinterlegung ist in Deutschland in den letzten Jahren zum üblichen Bestandteil eines wirksamen Risikomanagements
geworden. Softwareh?user k?nnen davon genauso profitieren wie deren Kunden. Dieser Artikel erg?nzt auch den Artikel “Escrow
Management bei elektronischer Archivierung” von Frau Rechtsanw?ltin Prof. Ursula Sury1 um die rechtlichen und technischen Aspekte der Quellcodehinterlegung. 相似文献
165.
Volker Wittwer 《Renewable Energy》1994,5(1-4)
The new class of transparent insulation materials is classified and characterisation methods are summarised. An overview on available materials and a comparison of these new materials with conventional glazing systems is given. The high potential of these materials in collector systems is briefly discussed. In the final section an overview on new optical switching materials is given, which may help to achieve economically interesting system costs. 相似文献
166.
This study focused on analyzing active pathways and the metabolic flux distribution in human neuronal AGE1.HN cells that is a desirable basis for a rational design and optimization of producing cell lines and production processes for biopharmaceuticals. 13C-labeling experiments and 13C metabolic flux analysis were conducted using glucose, glutamine, alanine and lactate tracers in parallel experiments. Connections between cytosolic and mitochondrial metabolite pools were verified, e.g., flux from TCA cycle metabolite 13C to glycolytic metabolites. It was also found that lactate and alanine are produced from the same pyruvate pool and that consumed alanine is mainly directly metabolized and secreted as lactate. Activity of the pentose phosphate pathway was low being around 2.3% of the glucose uptake flux. This might be compensated in AGE1.HN by high mitochondrial malic enzyme flux producing NADPH. Mitochondrial pyruvate transport was almost zero. Instead pyruvate carbons were channeled via oxaloacetate into the TCA cycle which was mainly fed via α-ketoglutarate and oxaloacetate during the investigated phase. The data indicate that further optimization of this cell line should focus on the improved substrate usage which can be accomplished by an improved connectivity between glycolytic and mitochondrial pyruvate pools or by better control of the substrate uptake. 相似文献
167.
Samuel Sutiono Okke Melse Manuel Döring Petra Lommes Volker Sieber 《Advanced Synthesis \u0026amp; Catalysis》2024,366(2):299-308
Polybutylene succinate (PBS) is one of the most important biobased plastics, based on the amount produced. Owing to its high melting point and resemblance to petroleum-based plastics (i. e. PP), PBS becomes one of the emerging bioplastics with an array of applications. PBS is manufactured by polymerization of 1,4-butanediol and succinic acid. Thus, it is of great importance to ensure the use of renewable resources to produce the PBS precursors. As the second most abundant carbohydrate monomer on Earth, D-xylose will be a suitable candidate for this purpose. In this work, we combined protein engineering with chemical oxidation by gold catalyst to enable transformation of D-xylose to 1,4-butanediol and succinic acid simultaneously. In silico docking studies and semi rational design were employed to create variants of the key enzyme, branched chain α-keto acid decarboxylase (KdcA) with higher affinity for the intermediates in the production of 1,4-butanediol and succinic acid. Direct enzymatic biotransformation would result in a production of both monomers with 3:1 ratio, thus not readily suitable for a direct polymerization to PBS. By developing a one-pot multi-step chemo-enzymatic approach with a gold catalyst to perform the first oxidation step, we could achieve a final product ratio of 1:1. Application of an engineered KdcA variant allowed us to achieve >98% yield after four hours transformation. In contrast, after 24 h transformation, >10% intermediate was still observed when the original variant was used. We anticipate this new approach could serve as an alternative route for biotechnological productions of PBS and its precursors. 相似文献
168.
Volker Schirrmacher Stefaan van Gool Wilfried Stuecker 《International journal of molecular sciences》2022,23(21)
An apparent paradox exists between the evidence for spontaneous systemic T cell- mediated anti-tumor immune responses in cancer patients, observed particularly in their bone marrow, and local tumor growth in the periphery. This phenomenon, known as “concomitant immunity” suggests that the local tumor and its tumor microenvironment (TME) prevent systemic antitumor immunity to become effective. Oncolytic Newcastle disease virus (NDV), an agent with inherent anti-neoplastic and immune stimulatory properties, is capable of breaking therapy resistance and immunosuppression. This review updates latest information about immunosuppression by the TME and discusses mechanisms of how oncolytic viruses, in particular NDV, and cellular immunotherapy can counteract the immunosuppressive effect of the TME. With regard to cellular immunotherapy, the review presents pre-clinical studies of post-operative active-specific immunotherapy and of adoptive T cell-mediated therapy in immunocompetent mice. Memory T cell (MTC) transfer in tumor challenged T cell-deficient nu/nu mice demonstrates longevity and functionality of these cells. Graft-versus-leukemia (GvL) studies in mice demonstrate complete remission of late-stage disease including metastases and cachexia. T cell based immunotherapy studies with human cells in human tumor xenotransplanted NOD/SCID mice demonstrate superiority of bone marrow-derived as compared to blood-derived MTCs. Results from clinical studies presented include vaccination studies using two different types of NDV-modified cancer vaccine and a pilot adoptive T-cell mediated therapy study using re-activated bone marrow-derived cancer-reactive MTCs. As an example for what can be expected from clinical immunotherapy against tumors with an immunosuppressive TME, results from vaccination studies are presented from the aggressive brain tumor glioblastoma multiforme. The last decades of basic research in virology, oncology and immunology can be considered as a success story. Based on discoveries of these research areas, translational research and clinical studies have changed the way of treatment of cancer by introducing and including immunotherapy. 相似文献
169.
Weise W Wilken V Koch C 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2002,49(7):937-945
The frequency response of a fiber-optic hydrophone that uses a dielectric multilayer system as the sensing element for ultrasound detection is investigated. A primary interferometric calibration technique is applied to determine by experiment the frequency-dependent pressure-voltage transfer function up to 45 MHz. The interaction between an incident pressure wave and the fiber end is analyzed by finite element methods. The simulation yields the response of the sensor to a short Gaussian impulse in the time domain from which the transfer function is calculated. The results of the model simulations allowed the transfer function obtained to be interpreted as the result of the superposition of longitudinal, edge diffraction and lateral waves with a resonant vibration mode of the fiber body representing an elastic rod 相似文献
170.
Trace theory has been developed to describe the behavior of concurrent systems. Synchronization of traces is of special interest for a modular approach. We characterize those trace monoids for which synchronization can be described locally. 相似文献