An Investigation into the Radiation Damage of the Silicon Detectors of the H1-PLUG Calorimeter within the HERA environment

The silicon detectors used in the H1-PLUG calorimeter have shown increasing aging effects during the '94 run period of the electron proton storage ring HERA. These effects were particularly manifest as degradation of the signal to noise level and the calibration stability. The reasons for this behaviour have been found to be correlated with radiation damage to the silicon oxide passivation edges of the detectors in strong and fluctuating increases of the leakage currents and in severe changes of the flat band voltages. Depletion voltages however are found to be stable and therefore bulk damage of the silicon can be excluded. A comparison with measurements made by thermoluminescence dosimeters as well as related laboratory experiments suggest that the aging is due to very low energetic electrons and photons.Comment: 17 pages, latex, 21 figures, eps-format, appende

Oncogenic senescence: a multi-functional perspective.

Cellular senescence is defined as an irreversible growth arrest with the acquisition of a distinctive secretome. The growth arrest is a potent anticancer mechanism whereas the secretome facilitates wound healing, tissue repair, and development. The senescence response has also become increasingly recognized as an important contributor to aging and age-related diseases, including cancer. Although oncogenic mutations are capable of inducing a beneficial senescence response that prevents the growth of premalignant cells and promotes cancer immune-surveillance, the secretome of senescent cells also includes factors with pro-tumorigenic properties. On June 23rd and 24th, 2016, the Division of Cancer Biology of the National Cancer Institute sponsored a workshop to discuss the complex role of cellular senescence in tumorigenesis with the goal to define the major challenges and opportunities within this important field of cancer research. Additionally, it was noted how the development of novel tools and technologies are required to accelerate research into a mechanistic understanding of senescent cells in carcinogenesis in order to overcome the current limitations in this exciting, yet ill-defined area

Leitlinien „Wissenschaft als Beruf attraktiv machen – Gute und faire Arbeits- und Beschäftigungsbedingungen für den akademischen Mittelbau“

Dem wissenschaftlichen Nachwuchs, seinem Engagement, seinen Ideen und seiner Kreativität kommt eine Schlüsselrolle in der Wissenschaft zu. Seine Förderung sowohl im Graduierten- als auch im Postgraduierten-Bereich gehört deshalb zu den wichtigsten Aufgaben einer Universität. Gleichzeitig gilt es, die Arbeits- und Beschäftigungsbedingungen für Beschäftigte mit Dauerstellen im Bereich der wissenschaftlichen Dienstleistungen gut und fair zu gestalten. Daneben zählt es zu den Aufgaben einer verantwortlichen akademischen Personalentwicklung, Karrieren außerhalb der Wissenschaft zu ermöglichen und besser planbar zu machen. Wir wollen gemeinsam gute und faire Arbeits- und Beschäftigungsbedingungen für den gesamten akademischen Mittelbau gestalten

Improved fluorescent probes for the measurement of rapid changes in membrane potential

To improve the quality of fluorescent voltage-sensitive probes twenty new styryl dyes were synthesized. Some of the new probes are significantly better than any used in the past. A signal-to-noise ratio of 90 root mean square (rms) noise was obtained for an optical recording of action potentials from neuroblastoma cells maintained in monolayer culture. The fluorescence fractional change of the optical signal is as large as 14%/100 mV. Photodynamic damage and bleaching are much less significant with the new probes. These fluorescent probes can be used to measure small and rapid changes in membrane potential from single cells maintained in monolayer cultures, from single cells in invertebrate ganglia, from their arborization, and from other preparations. The optical measurement can be made with a standard fluorescent microscope equipped with DC mercury illumination. Guidelines for the design of even better fluorescent probes and more efficient instruments are suggested

Internal knowledge exploitation - the role of sales force integration in new product development

This dissertation focuses on the distinct role of sales force integration in generating improved new product performance outcomes. Drawing on the resource-based view of the firm, we argue that the company-internal processing of the market information provided by salespeople represents a critical resource that allows for the development of successful new products via new product advantages and the adoption of new products by salespeople. Data pertaining to 219 new product projects and 269 companies from various industries provide empirical evidence that the intensity of sales force integration in the context of new product development significantly affects new product success beyond the effect of marketing integration. The study results also demonstrate that information quality and timing influence the effectiveness of sales force integration in achieving superior new product offerings and higher levels of new product success. The authors provide implications for decision makers in new product development and discuss avenues for further research

Fitness costs of delayed pollination in a mixed-mating plant

Background and Aims To predict the evolutionary consequences of pollinator declines, we need to understand the evolution of delayed autonomous self-pollination, which is expected to evolve as a mechanism of reproductive assurance when cross-pollination becomes unreliable. This involves estimating the costs of increased levels of selfing as well as those associated with floral senescence. Methods We studied the mechanisms and costs of delayed self-pollination in the mixed-mating vine Dalechampia scandens (Euphorbiaceae) by first assessing among-population variation in herkogamy and dichogamy, which together determine the rate and timing of autonomous self-pollination. We then tested whether floral longevity responds plastically to delayed pollination. Finally, we assessed the costs of delayed self-pollination in terms of seed number and size, explicitly separating inbreeding depression from effects of floral senescence. Key Results Herkogamy varied extensively, while variation in dichogamy was more limited. Unpollinated blossoms increased their longevity, but seed quantity and quality decreased with increasing delays in pollination, independently of inbreeding depression. Conclusions In D. scandens, earlier autonomous selfing is facilitated by reduced herkogamy rather than reduced protogyny, providing reproductive assurance while maintaining the possibility for outcrossing events. Effective early autonomous self-pollination may evolve under reduced cross-pollination reliability in response to costs associated with floral senescence

Chronik der Schule in Röllinghausen Kreis Alfeld Regierungs-Bezirk Hildesheim (ca. 1908–1957)

Dokument 20: Schulchronik von Röllinghausen (heute ein Ortsteil der Stadt Alfeld im Landkreis Hildesheim) von den Anfängen bis ins Jahr 1957. Provenienz: Stiftung Schulmuseum Hildesheim, Manuskripte, Röllinghausen: Schulchroniken, Nr.

Chronik der Schule in Eime Kreis Gronau/Alfeld Regierungs-Bezirk Hildesheim (ca. 1908–1961)

Dokument 17: Schulchronik von Eime (heute Teil der Samtgemeinde Leinebergland im Landkreis Hildesheim) von den Anfängen bis ins Jahr 1961. Provenienz: Stiftung Schulmuseum Hildesheim, Manuskripte, Eime: Schulchroniken, Nr.